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Sample records for sm gd ta

  1. Interband transitions in 106Pd, 152Sm, 152Gd and 182W

    International Nuclear Information System (INIS)

    Kartashov, V.M.; Oborovskij, A.I.; Troitskaya, A.G.

    1990-01-01

    Internal transitions in 106 Pd, 152 Sm, 152 Gd, 182 W nuclei, observed during decay of 152,152m Eu, 182,183 Ta, 106m Ag, are studied. The experimental characteristics of E0-transitions and E0-components of E0+M1+E2 type transitions in the studied nuclei, relative intensities of internal conversion electron lines during 182 Ta decay, multipolar composition and forbidden factor for 182 W and 183 W low-energy transitions, characteristics of transitions are presented

  2. ions (RE = La, Pr, Nd, Sm, Gd and Dy)

    Indian Academy of Sciences (India)

    ) zirconia), tendency of phase transformation (tetragonal to monoclinic () zirconia) and lattice strain were studied with mechanical property e.g. tensile strength of sol–gel derived ZrO2–2 mol% RE2O3 (RE = La, Pr, Nd, Sm, Gd and Dy) spun ...

  3. Temperature dependence of spin and orbital magnetic moments of Sm 4f electrons in (Sm, Gd)Al2

    International Nuclear Information System (INIS)

    Qiao, S.; Kimura, A.; Adachi, H.; Iori, K.; Miyamoto, K.; Xie, T.; Namatame, H.; Taniguchi, M.; Tanaka, A.; Muro, T.; Imada, S.; Suga, S.

    2005-01-01

    X-ray magnetic circular dichroism studies were carried out on (Sm, Gd)Al 2 , a ferromagnet without net magnetization at a certain compensation temperature. For Sm 4f electrons, the following understandings were obtained: the magnitude of expectation value of orbital magnetic moment (m L Sm ) is always larger than that of spin one (m S Sm ), so the cancellation of total spin and orbital magnetic moments cannot be achieved only by Sm 4f electrons and the contributions from Gd ions and conduction electrons are important; when the temperature decreases, the magnitude of both m L Sm and m S Sm increases and the gross magnetic moment due to the Sm 4f electrons monotonically deviates from zero. These results tell us that the temperature dependence of magnetic moments related with the electrons other than Sm 4f ones may play important roles in the subtle adjustment of the total spin and orbital magnetic moments to the zero magnetization at the compensation temperature

  4. Isomer decay spectroscopy of 164Sm and 166Gd: midshell collectivity around N=100.

    Science.gov (United States)

    Patel, Z; Söderström, P-A; Podolyák, Zs; Regan, P H; Walker, P M; Watanabe, H; Ideguchi, E; Simpson, G S; Liu, H L; Nishimura, S; Wu, Q; Xu, F R; Browne, F; Doornenbal, P; Lorusso, G; Rice, S; Sinclair, L; Sumikama, T; Wu, J; Xu, Z Y; Aoi, N; Baba, H; Bello Garrote, F L; Benzoni, G; Daido, R; Fang, Y; Fukuda, N; Gey, G; Go, S; Gottardo, A; Inabe, N; Isobe, T; Kameda, D; Kobayashi, K; Kobayashi, M; Komatsubara, T; Kojouharov, I; Kubo, T; Kurz, N; Kuti, I; Li, Z; Matsushita, M; Michimasa, S; Moon, C-B; Nishibata, H; Nishizuka, I; Odahara, A; Şahin, E; Sakurai, H; Schaffner, H; Suzuki, H; Takeda, H; Tanaka, M; Taprogge, J; Vajta, Zs; Yagi, A; Yokoyama, R

    2014-12-31

    Excited states in the N=102 isotones 166Gd and 164Sm have been observed following isomeric decay for the first time at RIBF, RIKEN. The half-lives of the isomeric states have been measured to be 950(60) and 600(140) ns for 166Gd and 164Sm, respectively. Based on the decay patterns and potential energy surface calculations, including β6 deformation, a spin and parity of 6- has been assigned to the isomeric states in both nuclei. Collective observables are discussed in light of the systematics of the region, giving insight into nuclear shape evolution. The decrease in the ground-band energies of 166Gd and 164Sm (N=102) compared to 164Gd and 162Sm (N=100), respectively, presents evidence for the predicted deformed shell closure at N=100.

  5. Isomer Decay Spectroscopy of Sm 164 and Gd 166 : Midshell Collectivity Around N =100

    Science.gov (United States)

    Patel, Z.; Söderström, P.-A.; Podolyák, Zs.; Regan, P. H.; Walker, P. M.; Watanabe, H.; Ideguchi, E.; Simpson, G. S.; Liu, H. L.; Nishimura, S.; Wu, Q.; Xu, F. R.; Browne, F.; Doornenbal, P.; Lorusso, G.; Rice, S.; Sinclair, L.; Sumikama, T.; Wu, J.; Xu, Z. Y.; Aoi, N.; Baba, H.; Bello Garrote, F. L.; Benzoni, G.; Daido, R.; Fang, Y.; Fukuda, N.; Gey, G.; Go, S.; Gottardo, A.; Inabe, N.; Isobe, T.; Kameda, D.; Kobayashi, K.; Kobayashi, M.; Komatsubara, T.; Kojouharov, I.; Kubo, T.; Kurz, N.; Kuti, I.; Li, Z.; Matsushita, M.; Michimasa, S.; Moon, C.-B.; Nishibata, H.; Nishizuka, I.; Odahara, A.; Şahin, E.; Sakurai, H.; Schaffner, H.; Suzuki, H.; Takeda, H.; Tanaka, M.; Taprogge, J.; Vajta, Zs.; Yagi, A.; Yokoyama, R.

    2014-12-01

    Excited states in the N =102 isotones Gd 166 and Sm 164 have been observed following isomeric decay for the first time at RIBF, RIKEN. The half-lives of the isomeric states have been measured to be 950(60) and 600(140) ns for Gd 166 and Sm 164 , respectively. Based on the decay patterns and potential energy surface calculations, including β6 deformation, a spin and parity of 6- has been assigned to the isomeric states in both nuclei. Collective observables are discussed in light of the systematics of the region, giving insight into nuclear shape evolution. The decrease in the ground-band energies of Gd 166 and Sm 164 (N =102 ) compared to Gd 164 and Sm 162 (N =100 ), respectively, presents evidence for the predicted deformed shell closure at N =100 .

  6. Absorption Spectra of BaF2 Sm2O3, Sm, Gd, and Ho Plasmas

    Science.gov (United States)

    Martin, Michael; Bastiani-Ceccotti, Serena

    2009-11-01

    Knowledge of the opacities of high Z element plasmas is important in indirect drive ICF and the study of stellar evolution. There are few experimental measurements of this quantity, and its theoretical determination is difficult due to the number of possible bound electron configurations. This study aims to better the theoretical understanding of this parameter by looking at the 3d-4f transitions of BaF2, Sm2O3, Sm, Gd, and Ho plasmas at the LULI2000 facility. The plasmas are produced by radiative heating and are cold, 15 -- 40 eV, and relatively dense, ˜ .01gm/cm^3 A plasma is produced by a .5 ns laser pulse irradiating a gold hohlraum and then probed by an x-ray source created by a gold foil irradiated by a 10 ps laser pulse. The transmission is found with simultaneous source and absorption measurements by an x-ray spectrometer in the 8 - 20 å range We will compare the results with statistical atomic structure codes. From this experiment we will gain further insight into the spectral broadening of neighboring Z elements due to changing plasma temperature and into mixture thermodynamics. This is a first step towards an experimental study of astrophysical domains.

  7. Analysis of the magnetic anisotropy in SmCo5 and GdCo5

    International Nuclear Information System (INIS)

    Zhao, T.; Jin, H.; Groessinger, R.; Kou, X.; Kirchmayr, H.R.

    1991-01-01

    The temperature dependence of the magnetic anisotropy constant K 1 for SmCo 5 and GdCo 5 is well reproduced by calculations based on a single-ion model taking into account the anisotropies of the R--Co exchange interaction and the Co-sublattice magnetic moment. The anisotropy of the R--Co exchange interaction plays an important role in reproducing the experimental K 1 (T) for SmCo 5 and GdCo 5 . It is found that the absolute value of the second order crystalline electric field parameter A 0 2 in SmCo 5 decreases monotonically with increasing temperature

  8. Experiment and density functional theory analyses of GdTaO4 single crystal

    Science.gov (United States)

    Ding, Shoujun; Kinross, Ashlie; Wang, Xiaofei; Yang, Huajun; Zhang, Qingli; Liu, Wenpeng; Sun, Dunlu

    2018-05-01

    GdTaO4 is a type of excellent materials that can be used as scintillation, laser matrix as well as self-activated phosphor has generated significant interest. Whereas its band structure, electronic structure and optical properties are still need elucidation. To solve this intriguing problem, high-quality GdTaO4 single crystal (M-type) was grown successfully using Czochralski method. Its structure as well as optical properties was determined in experiment. Moreover, a systematic theoretical calculation based on the density function theory methods were performed on M-type and M‧-type GdTaO4 and their band structure, density of state as well as optical properties were obtained. Combine with the performed experiment results, the calculated results were proved with high reliability. Hence, the calculated results obtained in this work could provide a deep understanding of GdTaO4 material, which also useful for the further investigation on GdTaO4 material.

  9. Isomer Decay Spectroscopy of Sm-164 and Gd-166: Midshell Collectivity Around N=100

    OpenAIRE

    Patel, Z; Soederstroem, P-A; Podolyak, Z; Regan, PH; Walker, PM; Watanabe, H; Ideguchi, E; Simpson, GS; Liu, HL; Nishimura, S; Wu, Q; Xu, FR; Browne, F; Doornenbal, P; Lorusso, G

    2014-01-01

    © 2014 American Physical Society. Excited states in the N=102 isotones Gd166 and Sm164 have been observed following isomeric decay for the first time at RIBF, RIKEN. The half-lives of the isomeric states have been measured to be 950(60) and 600(140) ns for Gd166 and Sm164, respectively. Based on the decay patterns and potential energy surface calculations, including β6 deformation, a spin and parity of 6- has been assigned to the isomeric states in both nuclei. Collective observables are disc...

  10. The isolation and the separation of Sm, Gd, Dy by extraction

    International Nuclear Information System (INIS)

    Biyantoro, D.; Lahagu, F.; Basuki, K.T.; Handini, T.; Rosyidin

    1996-01-01

    The isolation of yttrium and separation of Sm, Gd, y with extraction has been investigated. The steps of the process include of this research were the production the concentrate of lanthanide, the dilution, the isolation of yttrium, and the separation of the Sm, Gd, Dy. The first step was the digestion of xenotime sand, the extraction, the dilution, the filtration, the precipitation, the baking production a lanthanide oxide. The step was the separation of yttrium, the stripping, and the calcination production of yttrium oxide. And the third process was the separation of Sm, Gd, Dy by extraction process using method liquid-liquid extraction with extractant of D 2 EHPA and a solvent of dodecane. From the result have been found concentration of yttrium oxide = 88,71 %. The optimum condition of the separation of Gd/Dy have been found : the concentration of HNO 3 = 0,5 M, time of extraction = 15 minutes, and the concentration of extractant = 30 % D 2 EHPA in dodecane. The results of this condition were the distribution coefficient of Gd = 2,226, the distribution coefficient of Dy = 3,762, and the separation factor of Gd/Dy = 0,592. (author)

  11. Energy transfer mechanism from Gd3+ to Sm3+ in K3Gd(PO4)2:Sm3+ phosphor

    International Nuclear Information System (INIS)

    Gupta, Palvi; Bedyal, A K; Kumar, Vinay; Khajuria, Y; Sharma, Vishal; Ntwaeaborwa, O M; Swart, H C

    2015-01-01

    Undoped K 3 Gd(PO 4 ) 2 and trivalent samarium (0.5–2.5 mol%) doped K 3 Gd(PO 4 ) 2 phosphors were synthesized by the solid-state method. The phase formation, optical and luminescence properties were investigated by x-ray diffraction (XRD), diffuse reflectance (DR) spectroscopy, and photoluminescence (PL) spectroscopy. The fluorescence decay spectra of the obtained phosphors were also recorded to study the energy transfer from sensitizer (Gd 3+ ) to activator (Sm 3+ ). Energy transfer effects from sensitizer to activator caused by rare-earth ions were mainly observed in the obtained PL and lifetime spectra. The decay curves of K 3 Gd(PO 4 ) 2 phosphor with different Sm 3+ ions concentrations were found to be non-exponential and the data is well fitted with the Inokuti–Hirayama (I–H) model. The energy transfer parameters such as critical distance for the transfer processes were determined. The Commission Internationale de l’Eclairage (CIE) chromatic coordinates and color-correlated temperature were also determined for the prepared phosphor. (paper)

  12. Cross Section Measurements for Some Elements Suited as Thermal Spectrum indicators: Cd, Sm, Gd and Lu

    Energy Technology Data Exchange (ETDEWEB)

    Sokolowski, E; Pekarek, H; Jonsson, E

    1964-05-15

    The effective cross sections of Cd, Sm, Gd and Lu have been measured by the oscillator technique in the spectrum of the central channel of the Swedish reactor R1. For Cd, Sm and Gd the 2200 m/s cross sections were deduced on the basis of Westcott's g and s factors. The values obtained were generally in agreement with other recent values obtained by integral methods, although a systematic trend indicated that the value T{sub n} - T{sub m} = 29 {+-} 10 deg C for the neutron spectrum, measured with a fast chopper, was slightly too high. A new value of T{sub n} - T{sub m} = 22.5 {+-} 3.5 deg C was deduced and new 2200 m/s cross sections were obtained by iteration. For natural Lu, the energy dependence of the cross section is not well known. Certain assumptions about the cross section function led to unreasonably high values for the 2200 m/s cross section. Complementary differential measurements of the cross sections of Cd, Sm and Gd were made with the Rl fast chopper. For Cd and Sm the 2200 m/s cross section thus obtained agreed within experimental error with those obtained from the integral measurements. For Gd, the chopper measured value was higher, confirming earlier findings and indicating that the Westcott g factor for Gd is too high. Cd: Integral meas. : {sigma}(2200) = 2,390 {+-} 45 b; Differential meas. : {sigma}(2200) = 2,445 {+-} 25 b; Sm: Integral meas. : {sigma}(2200) = 5,880 {+-} 90 b; Differential meas. : {sigma}(2200) = 5,740 {+-} 150 b; Gd: Integral meas. : {sigma}(2200) = 46,470 {+-} 550 b; Differential meas. : {sigma}(2200) = 47,900 {+-} 700 b.

  13. Cross Section Measurements for Some Elements Suited as Thermal Spectrum indicators: Cd, Sm, Gd and Lu

    Energy Technology Data Exchange (ETDEWEB)

    Sokolowski, E.; Pekarek, H.; Jonsson, E.

    1964-05-15

    The effective cross sections of Cd, Sm, Gd and Lu have been measured by the oscillator technique in the spectrum of the central channel of the Swedish reactor R1. For Cd, Sm and Gd the 2200 m/s cross sections were deduced on the basis of Westcott's g and s factors. The values obtained were generally in agreement with other recent values obtained by integral methods, although a systematic trend indicated that the value T{sub n} - T{sub m} = 29 {+-} 10 deg C for the neutron spectrum, measured with a fast chopper, was slightly too high. A new value of T{sub n} - T{sub m} = 22.5 {+-} 3.5 deg C was deduced and new 2200 m/s cross sections were obtained by iteration. For natural Lu, the energy dependence of the cross section is not well known. Certain assumptions about the cross section function led to unreasonably high values for the 2200 m/s cross section. Complementary differential measurements of the cross sections of Cd, Sm and Gd were made with the Rl fast chopper. For Cd and Sm the 2200 m/s cross section thus obtained agreed within experimental error with those obtained from the integral measurements. For Gd, the chopper measured value was higher, confirming earlier findings and indicating that the Westcott g factor for Gd is too high. Cd: Integral meas. : {sigma}(2200) = 2,390 {+-} 45 b; Differential meas. : {sigma}(2200) = 2,445 {+-} 25 b; Sm: Integral meas. : {sigma}(2200) = 5,880 {+-} 90 b; Differential meas. : {sigma}(2200) = 5,740 {+-} 150 b; Gd: Integral meas. : {sigma}(2200) = 46,470 {+-} 550 b; Differential meas. : {sigma}(2200) = 47,900 {+-} 700 b.

  14. Thermoelectric power of RFeAsO (R = Ce, Pr, Nd, Sm and Gd)

    International Nuclear Information System (INIS)

    Poddar, Asok; Mukherjee, Sanjoy; Samanta, Tanmay; Saha, Rajat S.; Mukherjee, Rajarshi; Dasgupta, Papri; Mazumdar, Chandan; Ranganathan, R.

    2009-01-01

    Thermoelectric powers of a series of compounds RFeAsO (R = Ce, Pr, Nd, Sm and Gd) have been reported for temperatures ranging from 77 K up to room temperature. The behavior of S(T) in this temperature range can be divided into three regions. Every region has been fitted with mathematical functions of T. The physical significance of separate terms in the mathematical functions has been discussed. Some kind of universality has been observed between different members of the series.

  15. Thermoelectric power of RFeAsO (R = Ce, Pr, Nd, Sm and Gd)

    Energy Technology Data Exchange (ETDEWEB)

    Poddar, Asok, E-mail: asok.poddar@saha.ac.i [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064, West Bengal (India); Mukherjee, Sanjoy [Department of Physics, The University of Burdwan, Golapbag, Burdwan 713 104, West Bengal (India); Samanta, Tanmay [Rishra High School, 15 Tilakram Dan Ghat Lane, Rishra, Hooghly, West Bengal (India); Saha, Rajat S.; Mukherjee, Rajarshi [Department of Physics, University of Burdwan, Golapbag, Burdwan 713 104, West Bengal (India); Dasgupta, Papri; Mazumdar, Chandan; Ranganathan, R. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064, West Bengal (India)

    2009-07-15

    Thermoelectric powers of a series of compounds RFeAsO (R = Ce, Pr, Nd, Sm and Gd) have been reported for temperatures ranging from 77 K up to room temperature. The behavior of S(T) in this temperature range can be divided into three regions. Every region has been fitted with mathematical functions of T. The physical significance of separate terms in the mathematical functions has been discussed. Some kind of universality has been observed between different members of the series.

  16. Molecular electrophosphorescence in (Sm, Gd)-{beta}-diketonate complex blend for OLED applications

    Energy Technology Data Exchange (ETDEWEB)

    Reyes, R., E-mail: fisicaplic@hotmail.com [Facultad de Ingenieria Quimica y Textil, Universidad Nacional de Ingenieria, UNI, Av. Tupac Amaru 210, Lima 31, Peru (Peru); Cremona, M. [DIMAT - Divisao de Metrologia de Materiais, Instituto Nacional de Metrologia, Normalizacao e Qualidade Industrial, INMETRO, Duque de Caxias, RJ (Brazil); Departamento de Fisica, Pontificia Universidade Catolica do Rio de Janeiro, PUC-Rio, C.P. 38071, Rio de Janeiro, RJ, CEP 22453-970 (Brazil); Teotonio, E.E.S. [Departamento de Quimica, CCEN, Universidade Federal da Paraiba, UFPB, C.P. 5093, Joao Pessoa, PB, CEP 5805-970 (Brazil); Brito, H.F. [Instituto de Quimica, Universidade de Sao Paulo, USP, C.P. 26077, Sao Paulo, SP, CEP 05599-970 (Brazil); Malta, O.L. [Departamento de Quimica Fundamental, CCEN, Universidade Federal de Pernambuco, Cidade Universitaria, Recife, PE, CEP 50670-901 (Brazil)

    2013-02-15

    In this work the preparation and characterization of the triple-layer organic light-emitting diode (OLED) using a mixture of the samarium and gadolinium {beta}-diketonate complexes [Sm{sub 0.5}Gd{sub 0.5}(TTA){sub 3}(TPPO){sub 2}] as emitting layer is reported. The OLED's devices contain 1-(3-methylphenyl)-1,2,3,4-tetrahydroquinoline-6-carboxyaldehyde-1, 1'-diphenylhydrazone (MTCD) as hole-transporting layer and tris(8-hydroxyquinoline aluminum) (Alq{sub 3}) as electron transporting layer. The electroluminescence spectrum present emission narrow bands from the {sup 4}G{sub 5/2}{yields}{sup 6}H{sub J} transitions (where J=5/2, 7/2 and 9/2) characteristic of the Sm{sup 3+} ion. These sharp lines are overlapped with a broad band attributed to the electrophosphorescence from the T{sub 1}{yields}S{sub 0} transition in the ligand TTA. The intramolecular energy transfer is discussed and applied on the change of the emission color of the organic LEDs at different bias voltages. - Highlights: Black-Right-Pointing-Pointer Samarium and gadolinium complexes. Black-Right-Pointing-Pointer OLED with complex blend (Sm,Gd). Black-Right-Pointing-Pointer Electrophosphorescence emission detection. Black-Right-Pointing-Pointer Application in OLED changing the color emission.

  17. Molecular electrophosphorescence in (Sm, Gd)-β-diketonate complex blend for OLED applications

    International Nuclear Information System (INIS)

    Reyes, R.; Cremona, M.; Teotonio, E.E.S.; Brito, H.F.; Malta, O.L.

    2013-01-01

    In this work the preparation and characterization of the triple-layer organic light-emitting diode (OLED) using a mixture of the samarium and gadolinium β-diketonate complexes [Sm 0.5 Gd 0.5 (TTA) 3 (TPPO) 2 ] as emitting layer is reported. The OLED's devices contain 1-(3-methylphenyl)-1,2,3,4-tetrahydroquinoline-6-carboxyaldehyde-1, 1'-diphenylhydrazone (MTCD) as hole-transporting layer and tris(8-hydroxyquinoline aluminum) (Alq 3 ) as electron transporting layer. The electroluminescence spectrum present emission narrow bands from the 4 G 5/2 → 6 H J transitions (where J=5/2, 7/2 and 9/2) characteristic of the Sm 3+ ion. These sharp lines are overlapped with a broad band attributed to the electrophosphorescence from the T 1 →S 0 transition in the ligand TTA. The intramolecular energy transfer is discussed and applied on the change of the emission color of the organic LEDs at different bias voltages. - Highlights: ► Samarium and gadolinium complexes. ► OLED with complex blend (Sm,Gd). ► Electrophosphorescence emission detection. ► Application in OLED changing the color emission.

  18. 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.

  19. Sm2FeTaO7 Photocatalyst for Degradation of Indigo Carmine Dye under Solar Light Irradiation

    Directory of Open Access Journals (Sweden)

    Leticia M. Torres-Martínez

    2012-01-01

    Full Text Available This paper is focused to study Sm2FeTaO7 pyrochlore-type compound as solar photocatalyst for the degradation of indigo carmine dye in aqueous solution. Sm2FeTaO7 was synthesized by using conventional solid state reaction and sol-gel method. X-ray diffraction results indicated that Sm2FeTaO7 exhibit a monoclinic crystal structure. By scanning electron microscopy analysis, it was observed that sol-gel material presents particle size of around 150 nm. The specific surface area and energy bandgap values were 12 m2 g−1 and 2.0 eV, respectively. The photocatalytic results showed that indigo carmine molecule can be degraded under solar light irradiation using the synthesized materials, sol-gel photocatalyst was 8 times more active than solid state. On the other hand, when Sm2FeTaO7 was impregnated with CuO as cocatalyst the photocatalytic activity was increased because CuO acts as electron trap decreasing electron-hole pair recombination rates.

  20. Synthesis by two methods and crystal structure determination of a new pyrochlore-related compound Sm{sub 2}FeTaO{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Torres-Martinez, Leticia M., E-mail: lettorresg@yahoo.com [Departamento de Ecomateriales y Energia, Facultad de Ingenieria Civil, Universidad Autonoma de Nuevo Leon, Cd. Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); Ruiz-Gomez, Miguel A. [Departamento de Ecomateriales y Energia, Facultad de Ingenieria Civil, Universidad Autonoma de Nuevo Leon, Cd. Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); Facultad de Ciencias Quimicas, Universidad Autonoma de San Luis Potosi, Av. Manuel Nava 6, San Luis Potosi, S.L.P. 78290 (Mexico); Figueroa-Torres, M.Z.; Juarez-Ramirez, Isaias [Departamento de Ecomateriales y Energia, Facultad de Ingenieria Civil, Universidad Autonoma de Nuevo Leon, Cd. Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); Moctezuma, Edgar [Facultad de Ciencias Quimicas, Universidad Autonoma de San Luis Potosi, Av. Manuel Nava 6, San Luis Potosi, S.L.P. 78290 (Mexico); and others

    2012-04-16

    Graphical abstract: The monoclinic (space group C2/c) structure of a new compound, Sm{sub 2}FeTaO{sub 7} shows an alternating Sm-O and Fe/Ta-O layers. In the Fe/Ta-O layer, Fe/Ta1 and Fe/Ta3 cations are coordinated by six oxygen atoms, forming irregular octahedral interconnected into a hexagonal tungsten bronze (HTB) type network. The HTB layer is a fundamental framework in the pyrohlore-related structure. Highlights: Black-Right-Pointing-Pointer Pyrochlore-related compound Sm{sub 2}FeTaO{sub 7} prepared by solid state reaction and sol-gel. Black-Right-Pointing-Pointer Sm{sub 2}FeTaO{sub 7} crystallizes with a monoclinic crystal structure and space group C2/c. Black-Right-Pointing-Pointer The compound is synthesized by sol-gel at lower temperature and time than solid state. Black-Right-Pointing-Pointer Surface area of sol-gel Sm{sub 2}FeTaO{sub 7} is 10 times higher than that prepared by solid state. - Abstract: This paper reports on the synthesis of a new pyrochlore-related compound Sm{sub 2}FeTaO{sub 7} by both solid state reaction and sol-gel synthesis routes. Structural features were determined by X-ray powder diffraction and Rietveld refinement and were corroborated using Transmission Electron Microscopy (TEM). The results revealed that Sm{sub 2}FeTaO{sub 7} crystallized in the monoclinic system with space group C2/c and the following cell parameters: a = 13.1307(5) Angstrom-Sign , b = 7.5854(3) Angstrom-Sign , c = 11.6425(4) Angstrom-Sign and {beta} = 100.971(2) Degree-Sign . The monoclinic structure of Sm{sub 2}FeTaO{sub 7} showed an arrangement of alternating Sm-O and Fe/Ta-O layers and two types of irregular octahedra of Fe/Ta-O, which are interconnected into a hexagonal tungsten bronze (HTB)-type network. On the other hand, Sm{sub 2}FeTaO{sub 7} prepared by sol-gel was obtained with lower particle sizes than the solid state produced compound. The difference in particle size causes a difference of one order of magnitude in the specific surface area. In

  1. Crystal structure of RCoIn5 (R - Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Y) and R2CoIn8 (R - Ce, Pr, Nd, Sm, Gd, Dy, Ho, Er, Tm, Y) compounds

    International Nuclear Information System (INIS)

    Kalychak, Ya.M.; Zaremba, V.I.; Baranyak, V.M.; Bruskov, V.A.; Zavalij, P.Yu.

    1989-01-01

    Usng X-ray diffraction method of monocrystal, crystal structure of HoCoIn 5 compound belonging to the HoCoGa 5 structural type is determined. Using the method of powder belonging of CeCoIn 5 structure to the HoCoGa 5 structural type is confirmed. Isostructural compounds with Y, Pr, Nd, Sm, Gd, Tb, Dy are detected. Their lattice periods are determined. Using the method of powder belonging of Ce 2 CoIn 8 compound structure to Ho 2 CoGa 8 structural type is determined. Isostructural compounds with Y, Pr, Nd, Sm, Gd, Dy, Ho, Er, Tm are detected and their lattice periods are determined

  2. Methylene blue degradation by NaTaO3 sol-gel doped with Sm and La

    International Nuclear Information System (INIS)

    Torres-Martinez, Leticia M.; Cruz-Lopez, Arquimedes; Juarez-Ramirez, Isaias; Meza-de la Rosa, Ma. Elena

    2009-01-01

    In this work, NaTaO 3 compounds doped with 1 M% of La and Sm, were prepared by the sol-gel (SG) method and solid state (SS) reaction; and tested as photocatalysts on the degradation of methylene blue (MB) under UV light. The structural characterization by X-ray powder diffraction revealed that the crystallization of the NaTaO 3 phase prepared by the sol-gel method started at 600 deg. C, reaching maximum crystallization at 800 deg. C. It was determined that the presence of Sm and La retard the crystallization of the NaTaO 3 phase. On the other hand, the compounds synthesized in this work showed particle sizes in the nanometric scale, as it was observed by scanning electron microscopy (SEM). The specific surface area of the compounds synthesized by the sol-gel method, showed values 4 times higher than those obtained by the solid state reaction, favoring their functional and photocatalytic performance in the methylene blue degradation. In addition, the best photocatalytic performance was shown by the NaTaO 3 doped with Sm and heated at 600 deg. C, having a half-life time of 65 min.

  3. Calculations of the Low-Lying Structures in the Even-Even Nd/Sm/Gd/Dy Isotopes

    Science.gov (United States)

    Lee, Su Youn; Lee, J. H.; Lee, Young Jun

    2018-05-01

    The nuclear structure of deformed nuclei has been studied using the interacting boson model (IBM). In this study, energy levels and E2 transition probabilities were determined for even nuclei in the Nd/Sm/Gd/Dy chains which have a transition characteristic between the rotational, SU(3) and vibrational, U(5) limits. The structure of the nuclei exhibits a slight breaking of the SU(3) symmetry in the direction of U(5), and therefore, we add the d-boson number operator n d , which is the main term of the U(5) symmetric Hamiltonian, to the SU(3) Hamiltonian of the IBM. The calculated results for low-lying energy levels and E2 transition rates in Nd/Sm/Gd/Dy isotopes are in reasonably good agreement with known experimental results.

  4. Influence of Y, Gd and Sm on the glass forming ability and thermal crystallization of aluminum based alloy

    International Nuclear Information System (INIS)

    Aliaga, L.C.R.; Bolfarini, C.; Kiminami, C.S.; Botta Filho, W.J.; Danez, G.P.

    2010-01-01

    Al-based amorphous alloys represent an important family of metals and a great scientific activity has been devoted to determine the main features of both glass forming ability (GFA) and crystallization behavior in order to have a comprehensive framework aimed at potential technological applications. Nowadays, it is well known that the best Al-based amorphous alloys are formed in ternary systems such as Al- RE-TM, where RE is a rare earth and TM a transition metal. This paper presents results of research in Al 85 Ni 10 RE 5 alloys (RE = Y, Gd and Sm). Amorphous ribbons were processed by melt-spinning under the same conditions and subsequently characterized by x-ray diffraction (XRD) and differential scanning calorimetry (DSC). Results show appreciable micro structural differences as function of the rare earth, thus crystal is obtained for Y, nano-glassy for Gd and, fully amorphous structure for Sm. (author)

  5. Electronic and magnetic properties of SmCrSb3 and GdCrSb3: A first principles study

    International Nuclear Information System (INIS)

    Sandeep; Ghimire, M.P.; Thapa, R.K.

    2011-01-01

    The density of states (DOS) and the magnetic moments of SmCrSb 3 and GdCrSb 3 have been studied by first principles full-potential linearized augmented plane wave (FP-LAPW) method based on density functional theory (DFT). For the exchange-correlation potential, the local-spin density approximations with correlation energy (LSDA+U) method have been used. Total and partial DOS have been computed using the WIEN2k code. DOS result shows the exchange-splittings of Cr-3d and rare-earth (R) 4f states electrons, which are responsible for the ground state ferromagnetic (FM) behavior of the systems. The FM behavior of these systems is strongly influenced by the average number of Cr-3d and Sm (Gd) 4f-electrons. The effective moment of SmCrSb 3 is found to be 7.07 μ B while for GdCrSb 3 it is 8.27 μ B . The Cr atom plays a significant role on the magnetic properties due to the hybridization between Cr-3d and Sb-5p states. - Highlights: → DOS and the magnetic moments of SmCrSb 3 and GdCrSb 3 are studied by full-FP-LAPW method. → Exchange splitting of eg and t2g of Cr-3d states and the rare-earth 4f state electrons are responsible for ground state ferromagnetism. → Rare-earth magnetic moments are greater than Cr moment indicating presence of 4f states.

  6. Luminescent GdVO_4:Sm"3"+ quantum dots enhance power conversion efficiency of bulk heterojunction polymer solar cells by Förster resonance energy transfer

    International Nuclear Information System (INIS)

    Bishnoi, Swati; Gupta, Vinay; Sharma, Gauri D.; Chand, Suresh; Sharma, Chhavi; Kumar, Mahesh; Haranath, D.; Naqvi, Sheerin

    2016-01-01

    In this work, we report enhanced power conversion efficiency (PCE) of bulk heterojunction polymer solar cells by Förster resonance energy transfer (FRET) from samarium-doped luminescent gadolinium orthovanadate (GdVO_4:Sm"3"+) quantum dots (QDs) to polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7) polymer. The photoluminescence emission spectrum of GdVO_4:Sm"3"+ QDs overlaps with the absorption spectrum of PTB7, leading to FRET from GdVO_4:Sm"3"+ to PTB7, and significant enhancements in the charge-carrier density of excited and polaronic states of PTB7 are observed. This was confirmed by means of femtosecond transient absorption spectroscopy. The FRET from GdVO_4:Sm"3"+ QDs to PTB7 led to a remarkable increase in the power conversion efficiency (PCE) of PTB7:GdVO_4:Sm"3"+:PC_7_1BM ([6,6]-phenyl-C_7_1-butyric acid methyl ester) polymer solar cells. The PCE in optimized ternary blend PTB7:GdVO_4:Sm"3"+:PC_7_1BM (1:0.1:1.5) is increased to 8.8% from 7.2% in PTB7:PC_7_1BM. This work demonstrates the potential of rare-earth based luminescent QDs in enhancing the PCE of polymer solar cells.

  7. Energy transfer phenomena and Judd-Ofelt analysis on Sm{sup 3+} ions in K{sub 2}GdF{sub 5} crystal

    Energy Technology Data Exchange (ETDEWEB)

    Do, Phan Van [Thuyloi University, 175 Tay Son, Dong da Dist, Hanoi (Viet Nam); Tuyen, Vu Phi, E-mail: vptuyen@gust-edu.vast.vn [Graduate University of Science and Technology - VAST, 18 Hoang quoc Viet, Hanoi (Viet Nam); DuyTan University, K7/25 QuangTrung, Danang (Viet Nam); Quang, Vu Xuan [DuyTan University, K7/25 QuangTrung, Danang (Viet Nam); Khaidukov, Nicholas M. [Kurnakov Institute of General and Inorganic Chemistry, Moscow (Russian Federation); TrongThanh, Nguyen [Institute of Materials Science - VAST, 18 Hoang quoc Viet, Hanoi (Viet Nam); Sengthong, Bounyavong [DuyTan University, K7/25 QuangTrung, Danang (Viet Nam); Huy, Bui The, E-mail: buithehuy.nt@gmail.com [Department of Chemistry, Changwon National University, Changwon 641-773 (Korea, Republic of)

    2016-11-15

    The Raman, absorption, luminescence spectra and lifetimes curves of Sm{sup 3+}-doped K{sub 2}GdF{sub 5}were measured. Based on the Judd-Ofelt analysis, the values of radiative transition probabilities, branching ratios, integrated emission cross-sections and radiative lifetimes of excited states of Sm{sup 3+} in K{sub 2}GdF{sub 5} crystal were calculated. The migration of excitation energy between the Gd{sup 3+} ions and the trapping processes of Gd{sup 3+} excitation energy by Sm{sup 3+} and Tb{sup 3+}ions in K{sub 2}GdF{sub 5} crystal are reported. The role of the overlapping between the broad, allowed absorption bands of the RE{sup 3+} ions and the narrow absorption lines {sup 6}I{sub J} and {sup 6}P{sub J} of Gd{sup 3+} ions on the trapping rates of the RE{sup 3+} was discussed. The energy transfer between the Sm{sup 3+} ions was studied by the decay measurement, which has been fitted by Inokuti-Hirayama energy transfer model and revealed that electric dipole–quadrupole interaction is responsible for the energy transfer process in Sm{sup 3+} ions doped K{sub 2}GdF{sub 5} crystal.

  8. Mixing of the odd-parity excitations in Nd, Sm and Gd nuclei with 86 and 87 neutrons

    International Nuclear Information System (INIS)

    Hammaren, Esko.

    1978-08-01

    The low- and medium-spin structure of the four nuclei 148 Sm 86 , 147 Nd 87 , 149 Sm 87 and 151 Gd 87 has been investigated experimentally and theoretically. The low-spin states of 151 Gd were obtained in the EC and β + decay of 151 Tb. The proposed level scheme, based on gamma-gamma coincidence and conversion-electron measurements, contains several new energy levels, among them a 5/2 - state at 427 keV. Nanosecond lifetimes of the states in 147 Nd were studied using the reaction 146 Nd(d,pγ) 147 Nd with 10 MeV deuterons. The reactions sup(148,150)Nd( 3 He,xn) at Esup(3sub(He)) = 19 - 27 MeV were used to study excited states in the nuclei 148 Sm and 149 Sm. Gamma-ray excitation fuctions, angular and time distributions, gamma-gamma coincidences and conversion electrons were measured. The presence of the Z = 64 closed proton core is proposed to be important for the structure of the even and odd isotones considered. Calculations performed for 148 Sm using the interacting-boson-approximation model and related to the N = 82, Z = 64 and N = 82, Z = 50 cores are discussed. The properties of the negative-parity low-spin states of the N = 87 isotones are explained with an axial particle-plus-rotor model. The calculated B(M1) and B(E2) probabilities are compared with a compilation of experimental values. Most of the spectroscopic factors of 149 Sm are reproduced well in the calculation. The consequences of nonaxiality are discussed for the fsub(7/2)- and hsub(9/2)-based excitations. The standard Meyer-ter-Vehn model calculation indicates different asymmetries for the fsub(7/2) and hsub(9/2) shells. (author)

  9. Enhanced photoluminescence of Sm{sup 3+}/Bi{sup 3+} co-doped Gd{sub 2}O{sub 3} phosphors by combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Liu Guangsheng; Zhang Ying [Institute of Micro-system Physics, School of Physics and Electronics, Henan University, Kaifeng 475001 (China); Yin Jiang [Department of Physics, Nanjing University, Nanjing 210093 (China); Zhang, W.F. [Institute of Micro-system Physics, School of Physics and Electronics, Henan University, Kaifeng 475001 (China)], E-mail: wfzhang@henu.edu.cn

    2008-12-15

    Gd{sub 2}O{sub 3}:Sm{sup 3+} and Gd{sub 2}O{sub 3}:Sm{sup 3+},Bi{sup 3+} powders were prepared by a combustion method. Their structures were determined using X-ray diffraction. UV-visible absorption and photoluminescence spectra were investigated for Gd{sub 2}O{sub 3}:Sm{sup 3+} and Gd{sub 2}O{sub 3}:Sm{sup 3+},Bi{sup 3+} at different annealing temperatures and different doping concentrations. The emission spectra of all samples presented the characteristic emission narrow lines arising from the {sup 4}G{sub 5/2}{yields}{sup 6}H{sub J} transitions (J=5/2, 7/2, and 9/2) of Sm{sup 3+} ions upon excitation with UV irradiation. The emission intensity of Sm{sup 3+} ions was largely enhanced with introducing Bi{sup 3+} ions into Gd{sub 2}O{sub 3}:Sm{sup 3+} and the maximum occurred at a Bi{sup 3+} concentration of 0.5 mol%. The relevant mechanisms were discussed with the sensitization theory by Dexter and the aggregation behavior of Bi{sup 3+} ions.

  10. Investigations on the determination of traces of some rare earths (Eu, Sm, Gd, Y) in oxides of rare earths (Y2O3, Sm2O3, Gd2O3) by emission spectrography in d.c. arc

    International Nuclear Information System (INIS)

    Dittrich, K.; Gajek, M.; Luan, P.

    1978-01-01

    The evaporation of traces and matrices of rare earth elements was investigated in different atmospheres. It was found, that low-boiling rare earths elements, because of their extended formation of carbides evaporate more slowly than high-boiling rare earths elements. The evaporation of the traces depends on the matrices. 3 cases for the determination of traces of rare earths elements in oxides of other rare earths elements are derived from the results of the evaporation: Low- to high-boiling traces of rare earths elements in low-boiling matrices of rare earths elements, low-boiling traces in medium- to high-boiling matrices, and medium- to high-boiling traces in medium- to high-boiling matrices. The results of the determination are: in Y 2 O 3 : 14 ppm Sm, 2 ppm Eu; in Gd 2 O 3 : 18 ppm Y, 3 ppm Sm, 2 ppm Eu; in Sm 2 O 3 : 70 ppm Y, 370 ppm Gd, 16 ppm Eu. (author)

  11. Thermochemical properties of lanthanoid-iron-perovskite at high temperatures. [La, Nd, Sm, Eu, Gd, Tb, Dy

    Energy Technology Data Exchange (ETDEWEB)

    Katsura, T; Kitayama, K; Sugihara, T [Tokyo Inst. of Tech. (Japan). Faculty of Science; Kimizuka, N

    1975-06-01

    The standard Gibbs energy of formation of C/sup -/FeO/sub 3/(C/sup -/=La, Nd, Sm, Eu, Gd, Tb, and Dy) from metallic iron, C/sub 2//sup -/O/sub 3/, and oxygen has been determined at temperatures from 1473 to 1673 K. Based on the free-energy data, the heat of reaction and the entropy change resulting from the reaction have been calculated. The values of the heat of reaction of LaFeO/sub 3/, NdFeO/sub 3/, SmFeO/sub 3/, EuFeO/sub 3/, and GdFeO/sub 3/ (the first group) were identical, - 107 kcal/mol, at the present temperature interval. However, the values of the heat of reaction of TbFeO/sub 3/ and DyFeO/sub 3/ (the second group) decreased with an increase in the temperature. The entropy change of each reaction in the first group was constant, independent of the temperature, and each value decreased in the sequence from LaFeO/sub 3/ to GdFeO/sub 3/. The entropy change of the second group decreased with an increase in the temperature. The change of the standard Gibbs energy was intimately related to the ionic radii of C/sup -/-ions, and the relationship between the Gibbs energy and the tolerance factor has been clarified.

  12. Transition to intermediate valence state and x-ray photoemission in Sm/sub 1-x/Gd/sub x/S

    International Nuclear Information System (INIS)

    Campagna, M.; Chui, S.T.; Wertheim, G.K.; Tosatti, E.

    1976-01-01

    We report a systematic x-ray photoemission study of the alloys Sm 1 /sub -//subx/Gd/subx/S for 0 2+ → Sm 3+ photoemission line shape using a model which has some similarities with the Jaccarino-Walker model for magnetic alloys. It assumes the existence of only two different kinds of Sm 2+ ions in Sm 1 /sub -//subx/Gd/subx/S for x approximately-less-than 16%. We discuss possible reasons for the fact that Gd does not show the usual clustering effects known to occur in many substitutional rare-earth alloys. Lattice-constant measurements for various substituents further illustrate the importance of electronic effects in the phase transition

  13. Chemical surety material decontamination and decommissioning of Los Alamos National Laboratory Chemical Surety Material Laboratory area TA-3, building SM-29, room 4009

    International Nuclear Information System (INIS)

    Moore, T.E.; Smith, J.M.

    1994-04-01

    From 1982 through 1987, Los Alamos National Laboratory (LANL) performed surety laboratory operations for the U.S. Army Medical Research and Development Command (MRDC). Room 4009 in building SM-29, TA-3, was used as the laboratory for work with the following chemical surety material (CSM) agents: sarin (GB), soman (GD), lewisite (L), and distilled mustard (HD) radio-labelled with H 3 or C 14 . The work was confined to three CSM-certified fume hoods, located in room 4009 (see diagram in Appendix C). The laboratory ceased all active operations during the late 1986 and early 1987 period. From 1987 until 1993 the laboratory was secured and the ventilation system continued to operate. During late 1992, the decision was made to utilize this laboratory space for other operations, thus a decision was made to dismantle and reconfigure this room. LANL sub-contracted Battelle Memorial Institute (BMI) to draw upon the CSM experience of the technical staff from the Hazardous Materials Research Facility (HMRF) to assist in developing a decontamination and decommissioning plan. BMI was subcontracted to devise a CSM safety training course, and a sampling and air monitoring plan for CSM material to ensure personnel safety during all disassembly operations. LANL subcontracted Johnson Controls personnel to perform all disassembly operations. Beginning in early 1993 BMI personnel from the HMRF visited the laboratory to develop both the safety plan and the sample and air monitoring plan. Execution of that plan began in September 1993 and was completed in January 1994

  14. Magnetic properties of the germanides RE3Pt4Ge6 (RE=Y, Pr, Nd, Sm, Gd-Dy)

    International Nuclear Information System (INIS)

    Eustermann, Fabian; Eilers-Rethwisch, Matthias; Renner, Konstantin; Hoffmann, Rolf-Dieter; Poettgen, Rainer; Janka, Oliver; Oldenburg Univ.

    2017-01-01

    The germanides RE 3 Pt 4 Ge 6 (RE=Y, Pr, Nd, Sm, Gd-Dy) have been synthesized by arc-melting of the elements followed by inductive annealing to improve the crystallinity and allow for structural order. The compounds have been studied by powder X-ray diffraction; additionally the structure of Y 3 Pt 4 Ge 6 has been refined from single-crystal X-ray diffractometer data. It exhibits a (3+1)D modulated structure, indicating isotypism with Ce 3 Pt 4 Ge 6 . The crystal structure can be described as an intergrowth between YIrGe 2 - and CaBe 2 Ge 2 -type slabs along [100]. Temperature-dependent magnetic susceptibility measurements showed Pauli paramagnetism for Y 3 Pt 4 Ge 6 and Curie-Weiss paramagnetism for Pr 3 Pt 4 Ge 6 and Nd 3 Pt 4 Ge 6 . Sm 3 Pt 4 Ge 6 exhibits van Vleck paramagnetism, while antiferromagnetic ordering at T N =8.1(1) K and T N =11.0(1) K is observed for Gd 3 Pt 4 Ge 6 and Tb 3 Pt 4 Ge 6 , respectively.

  15. Synthesis RMn{sub 2}O{sub 5} (R = Gd and Sm) nano- and microstructures by a simple hydrothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Gangqiang, E-mail: zgq2006@snnu.edu.cn [School of Physics and Information Technology, Shaanxi Normal University, Xi' an 710062 (China); Liu Peng [School of Physics and Information Technology, Shaanxi Normal University, Xi' an 710062 (China); Hojamberdiev, Mirabbos [Shaanxi Key Laboratory of Nano-materials and Technology, Xi' an University of Architecture and Technology, Xi' an 710055 (China); Ge Bao [School of Physics and Information Technology, Shaanxi Normal University, Xi' an 710062 (China); Liu Yun; Miao Hongyan; Tan Guoqiang [College of Materials Science and Engineering, Shaanxi University of Science and Technology, Xi' an 710021 (China)

    2009-12-15

    Single-phase RMn{sub 2}O{sub 5} (R = Gd and Sm) nano- and microstructures have been successfully synthesized via a simple hydrothermal process at 250 deg. C for 24 h using NaOH as mineralizer. X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and selective area electron diffraction patterns (SAED) were used to characterize the as-synthesized GdMn{sub 2}O{sub 5} and SmMn{sub 2}O{sub 5} samples. The effect of NaOH concentration and the molar ratio of Mn{sup 2+}/Mn{sup 7+} on the morphology and size of the final products was studied, and a possible formation mechanism of RMn{sub 2}O{sub 5} (R = Gd and Sm) nanoplates and nanorods under hydrothermal conditions was proposed.

  16. Diode-pumped passively Q-switched Nd:GdTaO4 laser based on tungsten disulfide nanosheets saturable absorber at 1066 nm

    Science.gov (United States)

    Li, M. X.; Jin, G. Y.; Li, Y.

    2018-05-01

    In this paper, we investigated the passively Q-switched Nd:GdTaO4 laser based on tungsten disulfide (WS2) saturable absorber (SA). The preparation method of WS2 SA was to attach the WS2-alcohol dispersion onto the quartz substrates. The diode-pumped passively Q-switched Nd:GdTaO4 laser operated at a central wavelength of 1066 nm. The stable pulse output could be obtained at the single pulse width of 560 ns. In a word, WS2 seems to be a suitable saturable absorber for solid state lasers.

  17. Photophysical electronic structure of double-perovskites A{sub 2}GdTaO{sub 6} (A = Ba and Sr)

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Binita, E-mail: ghosh.binita@gmail.com [Department of Physics, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009 (India); Dutta, Alo [Department of Physics, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009 (India); Shannigrahi, Santiranjan [Institute of Materials Research and Engineering, Agency for Science Technology and Research, 3 Research Link, Singapore 117602 (Singapore); Sinha, T.P. [Department of Physics, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009 (India)

    2015-11-05

    X-ray photoemission spectroscopy (XPS) measurements of double perovskite oxides, Ba{sub 2}GdTaO{sub 6} and Sr{sub 2}GdTaO{sub 6} are performed in the energy window of 0–1300 eV. Density functional theory calculations are initiated with the Vienna ab initio Simulation Package to understand the electronic structure of the systems. The calculated DOS has been compared with the experimental valence band XPS spectra. It has been observed that the Ta-5d and O-2p states are hybridized in the valence band. The chemical shifts of these compounds suggest a mixed ionic and covalent character of the bonds, which has been used to explain the electrical conduction mechanism of the systems. The calculated ratio of the spin-orbit interaction energy for Ba 3d and 4d states matches well with the observed experimental results. - Highlights: • DFT calculations of Ba{sub 2}GdTaO{sub 6} and Sr{sub 2}GdTaO{sub 6} have been performed with VASP. • XPS measurements are performed in the energy window of 0–1300 eV. • The calculated DOS has been compared with the valence band XPS spectra. • Chemical shifts from XPS spectra have been used to explain the conduction mechanism.

  18. Photoluminescence characteristics of reddish-orange Eu{sup 3+} or Sm{sup 3+} singly-doped and Eu{sup 3+} and Sm{sup 3+} co-doped KZnGd(PO{sub 4}){sub 2} phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jun Ho; Bandi, Vengala Rao; Grandhe, Bhaskar Kumar; Jang, Ki Wan; Lee, Ho Sueb [Changwon National University, Changwon (Korea, Republic of); Yi, Soung Soo [Silla University, Busan (Korea, Republic of); Jeong, Jung Hyun [Pukyong National University, Busan (Korea, Republic of)

    2011-02-15

    Eu{sup 3+} or Sm{sup 3+} singly-doped and Eu{sup 3+} and Sm{sup 3+} co-doped KZnGd(PO{sub 4}){sub 2} phosphors were synthesized by using a conventional solid state reaction method at 750 .deg. C. The emission spectra of KZnGd{sub 1-x}(PO{sub 4}){sub 2}:Eu{sup 3+}{sub x} with {lambda}{sub ex} = 395 nm and KZnGd{sub 1-y}(PO{sub 4}){sub 2}:Sm{sup 3+}{sub y} with {lambda}{sub ex} = 403 nm phosphors showed intense {sup 5}D{sub 0} {yields} {sup 7}F{sub 1}, {sup 4}G{sub 5/2} {yields} {sup 6}H{sub 7/2} emission transitions at 595 nm and 599 nm, respectively. The optimum relative intensity of the KZnGd{sub 1-x-y}(PO{sub 4}){sub 2}:Eu{sup 3+}{sub x} , Sm{sup 3+}{sub y} phosphor was obtained for the doping concentrations of (x = 0.09, y = 0.01). In addition, the temperature dependent luminescence intensity of the synthesized phosphors was investigated and the thermal stability of the KZnGd(PO{sub 4}){sub 2}:Eu{sup 3+} phosphor was found to be higher than that of standard YAG:Ce{sup 3+} and KZnGd{sub 1-x-y}(PO{sub 4}){sub 2}:Eu{sup 3+}{sub x} Sm{sup 3+}{sub y} under near ultra-violet (NUV) light emitting diode excitation (LED). Therefore, we suggest that Eu{sup 3+} or Sm{sup 3+} singly-doped and Eu{sup 3+} and Sm{sup 3+} co-doped KZnGd(PO{sub 4}){sub 2} phosphors should be efficient for different red-color-emitting display device applications and NUV-LED-based white-light-emitting diodes.

  19. Study of the R-(Zr,W)-(O,N) (R = Y, Nd, Sm, Gd, Yb) oxynitride system

    Energy Technology Data Exchange (ETDEWEB)

    Tessier, Franck, E-mail: Franck.Tessier@univ-rennes1.fr [UMR CNRS 6226 ' Sciences Chimiques de Rennes' , equipe ' Verres et Ceramiques' , Universite de Rennes 1, 35042 Rennes cedex (France); Maillard, Pascal [UMR CNRS 6226 ' Sciences Chimiques de Rennes' , equipe ' Verres et Ceramiques' , Universite de Rennes 1, 35042 Rennes cedex (France); Orhan, Emmanuelle [Laboratoire Science des Procedes Ceramiques et Traitements de Surface, UMR CNRS 6638, Universite de Limoges, 123 Avenue Albert Thomas, 87060 Limoges cedex (France); Chevire, Francois [UMR CNRS 6226 ' Sciences Chimiques de Rennes' , equipe ' Verres et Ceramiques' , Universite de Rennes 1, 35042 Rennes cedex (France)

    2010-02-15

    The replacement of tantalum by the couple Zr/W within the RTa-O-N systems (R = Y, Nd, Sm, Gd, Yb), enables the preparation of novel oxide and oxynitride phases in the R-Zr-W-O-N system. R{sub 2}Zr{sub 2-x}W{sub x}O{sub 7+x} oxides exhibit the fluorite-type (x < 0.9) and scheelite (x {approx} 1) structures. Corresponding oxynitride compositions are of the fluorite-type and show different colors, for example in the case of ytterbium: pale yellow (x = 0.2 or 0.25), green (x = 0.5-0.8) and brown for the tungsten-rich samples (x = 0.9, 1). Photocatalytic activity measurements have been performed to investigate the overall water splitting behavior of these colored phases.

  20. Field and sample history dependence of the compensation temperature in Sm0.97Gd0.03Al2

    International Nuclear Information System (INIS)

    Vaidya, U.V.; Rakhecha, V.C.; Sumithra, S.; Ramakrishnan, S.; Grover, A.K.

    2007-01-01

    We present magnetization data on three polycrystalline specimens of Sm 0.97 Gd 0.03 Al 2 : (1) as-cast (grainy texture), (2) powder, and (3) re-melted fast-quenched (plate). The data are presented for nominally zero- (ZFC) and high-field-cooling (HFC) histories. A zero cross-over in magnetization curve at some temperature T=T 0 was seen in ZFC data on grainy and powder samples, but not in the plate sample. At fields surpassing magnetocrystalline anisotropy, a 4f magnetic moment flip was still evidenced by HFC data in all samples at a compensation temperature T comp , which must necessarily be treated as distinct from T 0 (T 0 may not even exist). Proper understanding of T comp should take account of thermomagnetic history effects

  1. Determination of diffusion coefficients for sulfide ions in solid electrolytes on the basis of BaSm2S4 and CaGd2S4

    International Nuclear Information System (INIS)

    Yurlov, I.S.; Ushakova, Yu.N.; Medvedeva, O.V.; Kalinina, L.A.; Shirokova, G.I.; Ananchenko, B.A.

    2007-01-01

    Coefficients of self-diffusion and coefficients of diffusion of the sulfur ion in solid electrolytes BaSm 2 S 4 and CaGd 2 S 4 are determined with recourse to methods of conductometry and potentiostatic chronoamperometry. A vacancy mechanism for the defect formation in solid solutions on the basis of barium thiosamarate and calcium thiogadolynate is proposed [ru

  2. Magnetism of cyano-bridged hetero-one-dimensional Ln3+-M3+ complexes (Ln3+ = Sm, Gd, Yb; M3+ = FeLS, Co).

    Science.gov (United States)

    Figuerola, Albert; Diaz, Carmen; Ribas, Joan; Tangoulis, Vassilis; Sangregorio, Claudio; Gatteschi, Dante; Maestro, Miguel; Mahía, José

    2003-08-25

    The reaction of Ln(NO(3))(3).aq with K(3)[Fe(CN)(6)] or K(3)[Co(CN)(6)] and 2,2'-bipyridine in water led to five one-dimensional complexes: trans-[M(CN)(4)(mu-CN)(2)Ln(H(2)O)(4) (bpy)](n)().XnH(2)O.1.5nbpy (M = Fe(3+) or Co(3+); Ln = Sm(3+), Gd(3+), or Yb(3+); X = 4 or 5). The structures for [Fe(3)(+)-Sm(3+)] (1), [Fe(3)(+)-Gd(3+)] (2), [Fe(3)(+)-Yb(3+)] (3), [Co(3)(+)-Gd(3+)] (4), and [Co(3)(+)-Yb(3+)] (5) have been solved; they crystallize in the triclinic space P1 and are isomorphous. The [Fe(3+)-Sm(3+)] complex is a ferrimagnet, its magnetic studies suggesting the onset of weak ferromagnetic 3-D ordering at 3.5 K. The [Fe(3+)-Gd(3+)] interaction is weakly antiferromagnetic. The isotropic nature of Gd(3+) allowed us to evaluate the exchange interaction (J = 0.77 cm(-)(1)).

  3. Thermoelectric properties, crystal and electronic structure of semiconducting RECuSe{sub 2} (RE = Pr, Sm, Gd, Dy and Er)

    Energy Technology Data Exchange (ETDEWEB)

    Esmaeili, Mehdi [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1 (Canada); Tseng, Yu-Chih [CANMET Materials, Natural Resources Canada, 183 Longwood Road South, Hamilton, Ontario L8P 0A5 (Canada); Mozharivskyj, Yurij, E-mail: mozhar@mcmaster.ca [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1 (Canada)

    2014-10-15

    Highlights: • Crystal and electronic structure of monoclinic and trigonal RECuSe{sub 2} phases. • Thermoelectric properties of the RECuSe{sub 2} phases. • Temperature stability of the RECuSe{sub 2} phases. - Abstract: The ternary RECuSe{sub 2} phases have been prepared and structurally characterized. They adopt either a monoclinic structure (P2{sub 1}/c, z = 4) for lighter rare earths (RE = Pr, Sm and Gd) or Cu-disordered trigonal structure for heavier rare-earths (P3{sup ¯}m1, z = 1, RE = Dy and Er). The resistivity and Seebeck coefficient measurements on GdCuSe{sub 2}, DyCuSe{sub 2} and ErCuSe{sub 2} indicate that the studied phases are p-type semiconductors with relatively small activation energies (0.045–0.11 eV). However, their electrical resistivities are too high (0.45–220 Ω cm at room temperature) to make them competitive thermoelectric materials. Electronic structure calculations indicate presence of a band gap in the RECuSe{sub 2} phases.

  4. Thermoelectric properties, crystal and electronic structure of semiconducting RECuSe2 (RE = Pr, Sm, Gd, Dy and Er)

    International Nuclear Information System (INIS)

    Esmaeili, Mehdi; Tseng, Yu-Chih; Mozharivskyj, Yurij

    2014-01-01

    Highlights: • Crystal and electronic structure of monoclinic and trigonal RECuSe 2 phases. • Thermoelectric properties of the RECuSe 2 phases. • Temperature stability of the RECuSe 2 phases. - Abstract: The ternary RECuSe 2 phases have been prepared and structurally characterized. They adopt either a monoclinic structure (P2 1 /c, z = 4) for lighter rare earths (RE = Pr, Sm and Gd) or Cu-disordered trigonal structure for heavier rare-earths (P3 ¯ m1, z = 1, RE = Dy and Er). The resistivity and Seebeck coefficient measurements on GdCuSe 2 , DyCuSe 2 and ErCuSe 2 indicate that the studied phases are p-type semiconductors with relatively small activation energies (0.045–0.11 eV). However, their electrical resistivities are too high (0.45–220 Ω cm at room temperature) to make them competitive thermoelectric materials. Electronic structure calculations indicate presence of a band gap in the RECuSe 2 phases

  5. Chemical surety material decontamination and decommissioning of Los Alamos National Laboratory Chemical Surety Material Laboratory area TA-3, building SM-29, room 4009

    Energy Technology Data Exchange (ETDEWEB)

    Moore, T.E.; Smith, J.M.

    1994-04-01

    From 1982 through 1987, Los Alamos National Laboratory (LANL) performed surety laboratory operations for the U.S. Army Medical Research and Development Command (MRDC). Room 4009 in building SM-29, TA-3, was used as the laboratory for work with the following chemical surety material (CSM) agents: sarin (GB), soman (GD), lewisite (L), and distilled mustard (HD) radio-labelled with H{sup 3} or C{sup 14}. The work was confined to three CSM-certified fume hoods, located in room 4009 (see diagram in Appendix C). The laboratory ceased all active operations during the late 1986 and early 1987 period. From 1987 until 1993 the laboratory was secured and the ventilation system continued to operate. During late 1992, the decision was made to utilize this laboratory space for other operations, thus a decision was made to dismantle and reconfigure this room. LANL sub-contracted Battelle Memorial Institute (BMI) to draw upon the CSM experience of the technical staff from the Hazardous Materials Research Facility (HMRF) to assist in developing a decontamination and decommissioning plan. BMI was subcontracted to devise a CSM safety training course, and a sampling and air monitoring plan for CSM material to ensure personnel safety during all disassembly operations. LANL subcontracted Johnson Controls personnel to perform all disassembly operations. Beginning in early 1993 BMI personnel from the HMRF visited the laboratory to develop both the safety plan and the sample and air monitoring plan. Execution of that plan began in September 1993 and was completed in January 1994.

  6. Full-profile fitting of emission spectrum to determine transition intensity parameters of Yb3+:GdTaO4

    International Nuclear Information System (INIS)

    Zhang Qingli; Sun Guihua; Ning Kaijie; Liu Wenpeng; Sun Dunlu; Yin Shaotang; Shi Chaoshu

    2016-01-01

    The Judd–Ofelt theoretic transition intensity parameters of luminescence of rare-earth ions in solids are important for the quantitative analysis of luminescence. It is very difficult to determine them with emission or absorption spectra for a long time. A “full profile fitting” method to obtain in solids with its emission spectrum is proposed, in which the contribution of a radiative transition to the emission spectrum is expressed as the product of transition probability, line profile function, instrument measurement constant and transition center frequency or wavelength, and the whole experimental emission spectrum is the sum of all transitions. In this way, the emission spectrum is expressed as a function with the independent variables intensity parameters , full width at half maximum (FWHM) of profile functions, instrument measurement constant, wavelength, and the Huang–Rhys factor S if the lattice vibronic peaks in the emission spectrum should be considered. The ratios of the experimental to the calculated energy lifetimes are incorporated into the fitting function to remove the arbitrariness during fitting and other parameters. Employing this method obviates measurement of the absolute emission spectrum intensity. It also eliminates dependence upon the number of emission transition peaks. Every experiment point in emission spectra, which usually have at least hundreds of data points, is the function with variables and other parameters, so it is usually viable to determine and other parameters using a large number of experimental values. We applied this method to determine twenty-five of Yb 3+ in GdTaO 4 . The calculated and experiment energy lifetimes, experimental and calculated emission spectrum are very consistent, indicating that it is viable to obtain the transition intensity parameters of rare-earth ions in solids by a full profile fitting to the ions’ emission spectrum. The calculated emission cross sections of Yb 3+ :GdTaO 4 also indicate

  7. Spectroscopic properties and laser performance at 1,066 nm of a new laser crystal Nd:GdTaO4

    Science.gov (United States)

    Peng, Fang; Yang, Huajun; Zhang, Qingli; Luo, Jianqiao; Liu, Wenpeng; Sun, Dunlu; Dou, Renqin; Sun, Guihua

    2015-03-01

    A new laser medium Nd3+:GdTaO4 single crystal with high optical quality was grown successfully by the Czochralski method, and its high-efficiency laser operation at 1,066 nm was demonstrated for the first time. The absorption cross section of the crystal at 808 nm is 5.098 × 10-20 cm2, and the full width at half maximum of this absorption band is about 6 nm. Spectral properties are investigated by Judd-Ofelt theory. The stimulated emission cross section at 1,066 nm is 3.9 × 10-19 cm2, and the fluorescence lifetime of 4F3/2 level is 178.4 μs. A diode end-pumped Nd:GdTaO4 laser at 1,066 nm with the maximum output power of 2.5 W is achieved in the continuous-wave mode. The optical-to-optical conversion efficiency and slope efficiency are 34.6 and 36 %, respectively. In addition, the fluorescence branching ratio of 4F3/2 → 4I9/2 transition reaches 44.4 %, indicating that Nd:GdTaO4 may be an efficient laser medium at 920 nm. All the results demonstrate that Nd:GdTaO4 crystal is a good candidate for laser diode-pumped laser material.

  8. Weak ferromagnetism in Re0.67Ca0.33FeO3 (Re=La, Sm, Gd) nanoparticles

    International Nuclear Information System (INIS)

    Li Jiangong; Kou Xinli; Qin Yong; He Haiying

    2003-01-01

    Perovskite-type complex ferrite Re 0.67 Ca 0.33 FeO 3 (Re=La, Sm, Gd) nanoparticles of nearly the same particle size were prepared using sol-gel method. The influence of rare-earth ions on weak ferromagnetism in the Re 0.67 Ca 0.33 FeO 3 nanoparticles has been studied. The spontaneous magnetization M s of the Sm 0.67 Ca 0.33 FeO 3 nanoparticles is greater than that of Gd 0.67 Ca 0.33 FeO 3 nanoparticles; and M s of Gd 0.67 Ca 0.33 FeO 3 nanoparticles is greater than that of La 0.67 Ca 0.33 FeO 3 nanoparticles. The ferromagnetic component arising from the Fe sublattice increases with the decreasing rare-earth ionic radii. The magnetization of the rare-earth ions in the Sm 0.67 Ca 0.33 FeO 3 nanoparticles is smaller than that in the Gd 0.67 Ca 0.33 FeO 3 nanoparticles. The influences of the geometric and intrinsic magnetic characters of rare-earth ions as well as the particle size of the nanoparticles on weak ferromagnetism are discussed

  9. Orange-red emitting Gd2Zr2O7:Sm3+: Structure-property correlation, optical properties and defect spectroscopy

    Science.gov (United States)

    Gupta, Santosh K.; Reghukumar, C.; Sudarshan, K.; Ghosh, P. S.; Pathak, Nimai; Kadam, R. M.

    2018-05-01

    Local structure analysis of dopant ion, understanding host to dopant energy transfer dynamics and defects characterization in a doped material which plays an important role in the designing a highly efficient opto-electronic material. In this connection a new Sm3+ doped Gd2Zr2O7 pyrochlore material was synthesized using gel-combustion technique and was characterized systematically using X-ray diffraction (XRD), time resolved photoluminescence spectroscopy (TRPLS), positron annihilation lifetime spectroscopy (PALS) and density functional theory (DFT) based ab-initio calculation. Based on DFT site selective energetics calculation and luminescence decay measurement, it was observed that the Sm3+ was distributed at both Gd3+ and Zr4+ site with higher Sm3+ fraction at the Gd3+ site. PALS was used to probe the presence of defects in the phosphor. In this work intense orange-red emission is realized through manipulating the energy transfer from host defect emission (oxygen vacancies) to Sm3+ which allows color emission from green in undoped to orange-red in doped samples. Effect of dopant concentration and annealing temperature was probed using TRPLS and PALS. These all information is highly important for researcher looking to achieve pyrochlore based phosphor materials with high quantum yield.

  10. Combustion synthesis and characterization of MV0.5P0.5O4: Sm3+, Tm3+ (M = Gd, La, Y)

    Science.gov (United States)

    Motloung, Selepe J.; Lephoto, Mantwa A.; Tshabalala, Kamohelo G.; Ntwaeaborwa, Odireleng M.

    2018-04-01

    In this paper, GdV0.5P0.5O4: Sm3+, Tm3+, LaV0.5P0.5O4: Sm3+, Tm3+ and YV0.5P0.5O4: Sm3+, Tm3+ phosphor powders were prepared by solution combustion method using urea as a fuel. The phase purity, surface morphology, optical and photoluminescence properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-vis spectroscopy and photoluminescence spectroscopy. The XRD results indicated that the prepared powders are of a single phase and crystallized in tetragonal structure for Gd and Y systems while monoclinic phase was observed for La system. SEM showed that the samples consisted of mixed structures. The estimated band gaps were 2.2, 2.4 and 2.3 eV for Y, Gd and La systems respectively. The photoluminescence results showed four emission peaks. One peak is assigned to 1G4 - 3H6 transition of Tm3+, and three other emission peaks are attributed to 6G5/2 - 6H5/2, 6G5/2 - 6H7/2 and 6G5/2 - 6H9/2 transitions of Sm3+. The photoluminescent intensity was the highest in the gadolinium system.

  11. Observation of magnetization reversal behavior in Sm0.9Gd0.1Cr0.85Mn0.15O3 orthochromites

    Science.gov (United States)

    Panwar, Neeraj; Joby, Jostin P.; Kumar, Surendra; Coondoo, Indrani; Vasundhara, M.; Kumar, Nitu; Palai, Ratnakar; Singhal, Rahul; Katiyar, Ram S.

    2018-05-01

    Impact of co-doping (Gd and Mn) on the magnetic properties has been systematically investigated in SmCrO3 compound. For the synthesized compound Sm0.9Gd0.1Cr0.85Mn0.15O3 (SGCMO), below the Neel transition temperature and under low applied magnetic field, temperature induced magnetization reversal at 105 K (crossover temperature) was noticed in the field cooled magnetization curve. Magnetization reversal attained maximum value of -1.03 emu/g at 17 K where spin reorientation occurred. The magnetization reversal disappeared under higher applied field. From the M-H plots an enhancement in the magnetization was observed due to Gd doping. Magnetocaloric effect at low temperatures measured through the magnetic entropy change was found sixteen times higher for this compound as compared to pristine SmCrO3 and twice to that of SmCr0.85Mn0.15O3 compound. The study reveals the importance of co-doping in tailoring the magnetic properties of rare-earth chromites.

  12. Hyperfine fields at some 4d, 5d and 4f impurities in ferromagnetic GdZn and GdCd

    International Nuclear Information System (INIS)

    Kasamatsu, Y.; Kojima, K.; Hihara, T.

    1995-01-01

    Hyperfine (hf) fields at 4d (Y, Nb, Rh, Pd), 5d (Lu, Ta, Ir) and 4f (La, Nd, Sm, Eu) impurities in ferromagnetic GdZn and GdCd have been measured by NMR at 4.2 K. The local moment contributions to the hf field suggest that the impurity moments at the beginning and end of the d series are parallel and antiparallel to Gd moments, respectively. The hf results for 4f impurities are also discussed. ((orig.))

  13. The RELixSn2 (RE=La–Nd, Sm, and Gd; 0≤x<1) series revisited. Synthesis, crystal chemistry, and magnetic susceptibilities

    International Nuclear Information System (INIS)

    Makongo, Julien P.A.; Suen, Nian-Tzu; Guo, Shengping; Saha, Shanta; Greene, Richard; Paglione, Johnpierre; Bobev, Svilen

    2014-01-01

    This study is concerned with the ternary compounds RELi x Sn 2 (RE=La–Nd, Sm, and Gd; 0≤x 2 phases. These materials crystallize with the base-centered orthorhombic space group Cmcm (No. 63), and can be formally assigned with the CeNiSi 2 structure type (Pearson symbol oC16). Our systematic single-crystal X-ray diffraction studies revealed substantial Li-deficiencies in all cases, with SmSn 2 (space group Cmmm, ZrGa 2 structure type, Pearson symbol oC12) and GdSn 2 (space group Cmcm, ZrSi 2 structure type, Pearson symbol oC12) being completely lithium-free. The structure refinements also uncovered positional disorder on the Sn site neighboring the vacancies. The Sn-disorder and the Li-deficiency correlate, and vary monotonically with the decreased size of the rare-earth atoms in the order RE=La–Nd. The SmSn 2 and GdSn 2 structures are devoid of any disorder. Temperature-dependent studies of the magnetic response of the title compounds are also presented and discussed. -- Graphical abstract: RELi x Sn 2 (RE=La–Nd, 0≤x 2 structure type (a). The Sn-disorder and the Li-deficiency correlate, and vary monotonically with the decreased size of the rare-earth atoms in the order RE=La–Nd. The SmSn 2 (b) and GdSn 2 (c) structures are devoid of any disorder. Highlights: • The crystal structures of the RELi x Sn 2 (RE=La–Nd, 0≤x 2 structure type or defect variant of the CeNiSi 2 structure type. • SmSn 2 is isotypic with the ZrGa 2 structure, while RESn 2 (RE=Gd–Lu) are isotypic with the ZrSi 2 structure

  14. Preparation of SmBCO layer for the surface optimization of GdYBCO film by MOCVD process based on a simple self-heating technology

    Science.gov (United States)

    Zhao, Ruipeng; Zhang, Fei; Liu, Qing; Xia, Yudong; Lu, Yuming; Cai, Chuanbing; Tao, Bowan; Li, Yanrong

    2018-07-01

    The MOCVD process was adopted to grow the REBa2Cu3O7-δ ((REBCO), RE = rare earth elements) films on the LaMnO3 (LMO) templates. Meanwhile, the LMO-template tapes are heated by the joule effect after applying a heating current through the Hastelloy metal substrates. The surface of GdYBCO films prepared by MOCVD method is prone to form outgrowths. So the surface morphology of GdYBCO film is optimized by depositing the SmBCO layer, which is an important process method for the preparation of high-quality multilayer REBCO films. At last, the GdYBCO/SmBCO/GdYBCO multilayer films were successfully prepared on the LMO templates based on the simple self-heating method. It is demonstrated that the GdYBCO surface was well improved by the characterization analysis of scanning electron microscope. And the Δω of REBCO (005) and Δφ of REBCO (103), which were performed by an X-ray diffraction system, are respectively 1.3° and 3.3° What's more, the critical current density (Jc) has been more than 3 MA/cm2 (77 K, 0 T) and the critical current (Ic) basically shows a trend of good linear increase with the increase of the number of REBCO layers.

  15. Predictions of thermomagnetic properties of Laves phase compounds: TbAl2, GdAl2 and SmAl2 performed with ATOMIC MATTERS MFA computation system

    Science.gov (United States)

    Michalski, Rafał; Zygadło, Jakub

    2018-04-01

    Recent calculations of properties of TbAl2 GdAl2 and SmAl2 single crystals, performed with our new computation system called ATOMIC MATTERS MFA are presented. We applied localized electron approach to describe the thermal evolution of Fine Electronic Structure of Tb3+, Gd3+ and Sm3+ ions over a wide temperature range and estimate Magnetocaloric Effect (MCE). Thermomagnetic properties of TbAl2, GdAl2 and SmAl2 were calculated based on the fine electronic structure of the 4f8, 4f7 and 4f5 electronic configuration of the Tb3+ and Gd3+ and Sm3+ ions, respectively. Our calculations yielded: magnetic moment value and direction; single-crystalline magnetization curves in zero field and in external magnetic field applied in various directions m(T,Bext); the 4f-electronic components of specific heat c4f(T,Bext); and temperature dependence of the magnetic entropy and isothermal entropy change with external magnetic field - ΔS(T,Bext). The cubic universal CEF parameters values used for all CEF calculations was taken from literature and recalculated for universal cubic parameters set for the RAl2 series: A4 = +7.164 Ka04 and A6 = -1.038 Ka06. Magnetic properties were found to be anisotropic due to cubic Laves phase C15 crystal structure symmetry. These studies reveal the importance of multipolar charge interactions when describing thermomagnetic properties of real 4f electronic systems and the effectiveness of an applied self-consistent molecular field in calculations for magnetic phase transition simulation.

  16. Synthesis and magnetism of μ-oxamido-bridged Cu2IILnIII - type heterotrinuclear complexes (Ln = Ce, Nd, Sm, Eu, Gd, Tb, Dy, Er)

    International Nuclear Information System (INIS)

    Li, Y.T.; Yan, C.W.

    2001-01-01

    Eight new Cu 2 II Ln III - type (Ln = Ce, Nd, Sm, Eu, Gd, Tb, Dy, Er) heterotrinuclear complexes bridged by N,N'-bis (2-aminopropyl)oxamidocopper(II) [Cu(oxdn)], namely Cu 2 (oxdn)Ln(NO 3 ) 3 , have been synthesized and characterized by elemental analyses, molar conductivity measurements and spectroscopic (IR, UV, ESR) studies. Magnetic susceptibility measurements (4.2 ∼300 K) and studies of Cu 2 (oxdn)Gd(NO 3 ) 3 complex have revealed that the central gadolinium(III) and terminal copper(II) ions are ferromagnetically coupled with the exchange integral J (Cu-Gd) = +2.98 cm -1 , while an antiferromagnetic coupling is detected between the terminal copper(II) metal ions with the exchange integral J' (Cu-Gd) = -0.75 cm -1 , on the basis of the spin Hamiltonian operator [H -2J(S Cu1 -S Gd +S Cu2 +S Gd )-2J'(S Cu1 S Cu2 )]. (author)

  17. Study of a new magnetic dipole mode in the heavy deformed nuclei 154Sm, 156Gd, 158Gd, 164Dy, 168Er, and 174Yb by high-resolution electron spectroscopy

    International Nuclear Information System (INIS)

    Bohle, D.

    1985-01-01

    By inelastic electron scattering with high energy resolution a new magnetic dipole mode in heavy, deformed nuclei could be detected. For this the nuclei 154 Sm, 156 Gd, 158 Gd, 164 Dy, 168 Er, and 174 Yb were studied at the Darmstadt electron linear accelerator (DALINAC) at small momentum transfer q ≤ 0.6 fm -1 and low excitation energies. A collective magnetic dipole excitation could be discovered in all nuclei at an excitation energy of E x ≅ 66 δA -1/3 MeV whereby δ means the mass deformation. The transition strength extends in the mean to B(M1)↑ ≅ 1.3 μ N 2 . A systematic study of the nucleus 156 Gd yielded hints to a strong fragmentation of the magnetic dipole strength. A comparison of electron scattering, proton scattering, and nuclear resonance fluorescence experiments shows that the new mode is a pure orbital mode. (orig./HSI) [de

  18. Continuous-wave and acousto-optically Q-switched 1066 nm laser performance of a novel Nd:GdTaO4 crystal

    Science.gov (United States)

    Ma, Yufei; He, Ying; Peng, Zhenfang; Sun, Haiyue; Peng, Fang; Yan, Renpeng; Li, Xudong; Yu, Xin; Zhang, Qingli; Ding, Shoujun

    2018-05-01

    A diode-pumped acousto-optically (AO) Q-switched 1066 nm laser with a novel Nd:GdTaO4 crystal was demonstrated for the first time to the best of our knowledge. The optimization selection of output coupler was carried out in the continuous-wave (CW) operation. After that the pulsed Nd:GdTaO4 laser performances using different modulation repetition rates of 10 kHz and 20 kHz were investigated. At an absorbed pump power of 10 W and repetition rates of 10 kHz, the obtained minimum pulse width was 28 ns and the maximum peak power was 5.4 kW.

  19. Improved performance of Ta2O5-x resistive switching memory by Gd-doping: Ultralow power operation, good data retention, and multilevel storage

    Science.gov (United States)

    Shi, K. X.; Xu, H. Y.; Wang, Z. Q.; Zhao, X. N.; Liu, W. Z.; Ma, J. G.; Liu, Y. C.

    2017-11-01

    Resistive-switching memory with ultralow-power consumption is very promising technology for next-generation data storage and high-energy-efficiency neurosynaptic chips. Herein, Ta2O5-x-based multilevel memories with ultralow-power consumption and good data retention were achieved by simple Gd-doping. The introduction of a Gd ion, as an oxygen trapper, not only suppresses the generation of oxygen vacancy defects and greatly increases the Ta2O5-x resistance but also increases the oxygen-ion migration barrier. As a result, the memory cells can operate at an ultralow current of 1 μA with the extrapolated retention time of >10 years at 85 °C and the high switching speeds of 10 ns/40 ns for SET/RESET processes. The energy consumption of the device is as low as 60 fJ/bit, which is comparable to emerging ultralow-energy consumption (memory devices.

  20. Luminescent GdVO{sub 4}:Sm{sup 3+} quantum dots enhance power conversion efficiency of bulk heterojunction polymer solar cells by Förster resonance energy transfer

    Energy Technology Data Exchange (ETDEWEB)

    Bishnoi, Swati [CSIR-Network of Institutes for Solar Energy, New Delhi 110001 (India); Luminescent Materials and Devices Group, CSIR-National Physical Laboratory, New Delhi 110012 (India); Academy of Scientific and Innovative Research (AcSIR), CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012 (India); Gupta, Vinay, E-mail: drvinaygupta@netscape.net; Sharma, Gauri D.; Chand, Suresh [CSIR-Network of Institutes for Solar Energy, New Delhi 110001 (India); Organic and Hybrid Solar Cells Group, Physics of Energy Harvesting Division, CSIR-National Physical Laboratory, New Delhi 110012 (India); Sharma, Chhavi; Kumar, Mahesh [Ultrafast Optoelectronics and Terahertz Photonics Lab, Physics of Energy Harvesting Division, CSIR-National Physical Laboratory, New Delhi 110012 (India); Haranath, D. [CSIR-Network of Institutes for Solar Energy, New Delhi 110001 (India); Luminescent Materials and Devices Group, CSIR-National Physical Laboratory, New Delhi 110012 (India); Naqvi, Sheerin [Luminescent Materials and Devices Group, CSIR-National Physical Laboratory, New Delhi 110012 (India)

    2016-07-11

    In this work, we report enhanced power conversion efficiency (PCE) of bulk heterojunction polymer solar cells by Förster resonance energy transfer (FRET) from samarium-doped luminescent gadolinium orthovanadate (GdVO{sub 4}:Sm{sup 3+}) quantum dots (QDs) to polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7) polymer. The photoluminescence emission spectrum of GdVO{sub 4}:Sm{sup 3+} QDs overlaps with the absorption spectrum of PTB7, leading to FRET from GdVO{sub 4}:Sm{sup 3+} to PTB7, and significant enhancements in the charge-carrier density of excited and polaronic states of PTB7 are observed. This was confirmed by means of femtosecond transient absorption spectroscopy. The FRET from GdVO{sub 4}:Sm{sup 3+} QDs to PTB7 led to a remarkable increase in the power conversion efficiency (PCE) of PTB7:GdVO{sub 4}:Sm{sup 3+}:PC{sub 71}BM ([6,6]-phenyl-C{sub 71}-butyric acid methyl ester) polymer solar cells. The PCE in optimized ternary blend PTB7:GdVO{sub 4}:Sm{sup 3+}:PC{sub 71}BM (1:0.1:1.5) is increased to 8.8% from 7.2% in PTB7:PC{sub 71}BM. This work demonstrates the potential of rare-earth based luminescent QDs in enhancing the PCE of polymer solar cells.

  1. Low-frequency dielectric dispersion and magnetic properties of La, Gd modified Pb(Fe1/2Ta1/2)O3 multiferroics

    International Nuclear Information System (INIS)

    Choudhury, R.N.P.; Rodriguez, C.; Bhattacharya, P.; Katiyar, R.S.; Rinaldi, C.

    2007-01-01

    Pb(Fe 1/2 Ta 1/2 )O 3 (PFT) modified by rare-earth (La and Gd) ions has been synthesized in a single phase using a double-stage synthesis (i.e., Columbite) technique. Scanning electron micrographs (SEM) of the pellet samples have shown a significant change in their grain size and uniform distribution of Gd/La at the Fe-sites. The room temperature X-ray structural analysis shows that the reported cubic (or tetragonal) structure of PFT has been distorted to a monoclinic system on substitution of La/Gd at the Fe-site. Detailed studies of dielectric properties of the above compound on La/Gd substitution have shown strong dielectric dispersion at low frequency (i.e. relaxor behavior) with drastic change in transition temperature. Magnetic characterization shows that though the PFT sample displays an antiferromagnetic transition at ∼150 K, the rare-earth ions-substituted samples do not. Furthermore, temperature dependence of magnetization measurements shows that spin glass transition observed in PFT at low temperatures (5-20 K) does not exist in the La and Gd substituted PFT. Doping of Gd in PFT increases the sample magnetization, especially at low temperature

  2. White-emission in single-phase Ba2Gd2Si4O13:Ce3 +,Eu2 +,Sm3 + phosphor for white-LEDs

    Science.gov (United States)

    Jiang, Xiumin; Zhang, Yuqian; Zhang, Jia

    2018-03-01

    To develop new white-light-emitting phosphor, a series of Ce3 +-Eu2 +-Sm3 + doped Ba2Gd2Si4O13 (BGS) phosphors were prepared by the solid-state reaction method, and their photoluminescence properties were studied. The Ce3 + and Eu2 + single-doped BGS show broad emission bands around in the region of 350-550 and 420-650 nm, respectively. By co-doping Ce3 +-Eu2 + into BGS, the energy transfer (ET) from Ce3 + to Eu2 + is inefficient, which could be due to the competitive absorption between the two activator ions. The Sm3 +-activated BGS exhibits an orangey-red emission in the region of 550-750 nm. To achieve white emission, the BGS:0.06Ce3 +,0.04Eu2 +,ySm3 + (0 ≤ y ≤ 0.18) phosphors were designed, in which the ET from Ce3 +/Eu2 + to Sm3 + was observed. The emission color can be tuned by controlling the Sm3 + concentration, and white emission was obtained in the BGS:0.06Ce3 +,0.04Eu2 +,0.06Sm3 + sample. The investigation of thermal luminescence stability for the typical BGS:0.06Ce3 +,0.04Eu2 +,0.06Sm3 + sample reveals that the emission intensities of both Eu2 + and Sm3 + demonstrate continuous decrease but the Ce3 + emission is enhanced gradually with increasing temperature. The corresponding reason has been discussed.

  3. Influence of the Gd.sub.2./sub.BaCuO.sub.5./sub. fine particles on thermoelectric power of melt-textured (Nd-Sm-Gd) Ba.sub.2./sub.Cu.sub.3./sub.O.sub.7 -.delta../sub.

    Czech Academy of Sciences Publication Activity Database

    Okram, G. A.; Muralidhar, M.; Jirsa, Miloš; Murakami, M.

    2004-01-01

    Roč. 402, - (2004), s. 94-97 ISSN 0921-4534 Institutional research plan: CEZ:AV0Z1010914 Keywords : melt-textured materials * thermoelectric power * (Nd,Sm,Gd)Ba 2 Cu 3 O y * Gd 2 BaCuO 5 Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.072, year: 2004

  4. Microstructural analyses and critical current densities in the high-Tc superconductor system ReBa2Cu3OX, with RE = Y, Sm, Eu, Gd, Dy, Ho

    International Nuclear Information System (INIS)

    Schindler, G.; Seebacher, B.

    1989-01-01

    The authors report on investigations into the impact of the rare earths (RE) as given in the title on the ceramic microstructure and the critical current density j c in the superconductor system REBa 2 Cu 3 O x . With RE = Sm, Eu, or Gd, the material is homogeneous in phase and crystallizes in platelets with maximum sizes of up to 350 μm. Material with RE = Y, Dy, or Ho exhibits grain sizes up to 500 μm, and a low amount of phase inhomogeneities. The critical currents measured are between 25 Acm -2 and 290 Acm -2 at 77 K, without external field. The highest values are found in systems with RE = Eu or Gd. (orig.) [de

  5. Nanostructured LnBaCo2O6− (Ln = Sm, Gd with layered structure for intermediate temperature solid oxide fuel cell cathodes

    Directory of Open Access Journals (Sweden)

    Augusto E. Mejía Gómez

    2017-04-01

    Full Text Available In this work, we present the combination of two characteristics that are beneficial for solid oxide fuel cell (SOFC cathodic performance in one material. We developed and evaluated for the first time nanostructured layered perovskites of formulae LnBaCo2O6-d with Ln = Sm and Gd (SBCO and GBCO, respectively as SOFC cathodes, finding promising electrochemical properties in the intermediate temperature range. We obtained those nanostructures by using porous templates to confine the chemical reagents in regions of 200-800 nm. The performance of nanostructured SBCO and GBCO cathodes was analyzed by electrochemical impedance spectroscopy technique under different operating conditions using Gd2O3-doped CeO2 as electrolyte. We found that SBCO cathodes displayed lower area-specific resistance than GBCO ones, because bulk diffusion of oxide ions is enhanced in the former. We also found that cathodes synthesized using smaller template pores exhibited better performance.

  6. Ternary rhombohedral Laves phases RE_2Rh_3Ga (RE = Y, La-Nd, Sm, Gd-Er)

    International Nuclear Information System (INIS)

    Seidel, Stefan; Benndorf, Christopher; Heletta, Lukas; Poettgen, Rainer; Eckert, Hellmut; Sao Paulo Univ., Sao Carlos

    2017-01-01

    The ordered Laves phases RE_2Rh_3Ga (RE=Y, La-Nd, Sm, Gd-Er) were synthesized by arc-melting of the elements and subsequent annealing. The samples were characterized by powder X-ray diffraction (XRD). They crystallize with the rhombohedral Mg_2Ni_3Si type structure, space group R3m. Three structures were refined from single crystal X-ray diffractometer data: a=557.1(1), c=1183.1(2), wR2=0.0591, 159 F"2 values, 10 variables for Y_2Rh_3Ga, a=562.5(2), c=1194.4(2) pm, wR2=0.0519, 206 F"2 values, 11 variables for Ce_2Rh_3Ga and a=556.7(2), c=1184.1(3) pm, wR2=0.0396, 176 F"2 values, 11 variables for Tb_2Rh_3Ga. The Rh_3Ga tetrahedra are condensed via common corners and the large cavities left by the network are filled by the rare earth atoms. The RE_2Rh_3Ga Laves phases crystallize with a translationengleiche subgroup of the cubic RERh_2 Laves phases with MgCu_2 type. Magnetic susceptibility measurements reveal Pauli paramagnetism for Y_2Rh_3Ga and La_2Rh_3Ga. Ce_2Rh_3Ga shows intermediate cerium valence while all other RE_2Rh_3Ga phases are Curie-Weiss paramagnets which order magnetically at low temperatures. The "8"9Y and "7"1Ga solid state nuclear magnetic resonance (NMR) spectra of the diamagnetic representative Y_2Rh_3Ga show well-defined single resonances in agreement with an ordered bulk phase. In comparison to the binary Laves phase YRh_2 a strongly increased "8"9Y resonance frequency is observed owing to a higher s-electron spin density at the "8"9Y nuclei as proven by density of states (DOS) calculations.

  7. Influence of Y, Gd and Sm on the glass forming ability and thermal crystallization of aluminum based alloy; Efeito das terras raras Y, Gd e Sm na tendencia a formacao de amorfo e na cristalizacao termica em ligas a base de aluminio

    Energy Technology Data Exchange (ETDEWEB)

    Aliaga, L.C.R.; Bolfarini, C.; Kiminami, C.S.; Botta Filho, W.J., E-mail: aliaga@ufscar.b [Universidade Federal de Sao Carlos (DEMa/UFSCar), SP (Brazil). Dept. de Engenharia de Materiais; Danez, G.P. [Universidade Federal de Sao Carlos (PPG-CEMUFSCar), SP (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais

    2010-07-01

    Al-based amorphous alloys represent an important family of metals and a great scientific activity has been devoted to determine the main features of both glass forming ability (GFA) and crystallization behavior in order to have a comprehensive framework aimed at potential technological applications. Nowadays, it is well known that the best Al-based amorphous alloys are formed in ternary systems such as Al- RE-TM, where RE is a rare earth and TM a transition metal. This paper presents results of research in Al{sub 85}Ni{sub 10}RE{sub 5} alloys (RE = Y, Gd and Sm). Amorphous ribbons were processed by melt-spinning under the same conditions and subsequently characterized by x-ray diffraction (XRD) and differential scanning calorimetry (DSC). Results show appreciable micro structural differences as function of the rare earth, thus crystal is obtained for Y, nano-glassy for Gd and, fully amorphous structure for Sm. (author)

  8. Thermal decomposition of RE(C2H5CO2)3·H2O (RE = Dy, Tb, Gd, Eu and Sm)

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude

    2014-01-01

    The thermal decomposition of Dy(III), Tb(III), Gd(III), Eu(III), and Sm(III) propionate monohydrates was studied in argon by means of simultaneous differential thermal analysis and thermogravimetry, infrared-spectroscopy, X-ray diffraction, and optical microscopy. After dehydration, which takes......, an intermediate stage involving a RE2O(C2H5CO2)4 composition was evidenced in the case of the Eu- and Sm-propionates. For all compounds, further decomposition of RE2O2CO3 into the corresponding sesquioxides (RE2O3) is accompanied by the release of CO2. The thermal decomposition of Dy- and Tb-propionates occurs...

  9. Síntesis hidrotermal de monocristales LnMn2O5 (Ln= Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho y Er

    Directory of Open Access Journals (Sweden)

    Señarís Rodríguez, M. A.

    2008-08-01

    Full Text Available Ten single crystals of the series LnMn2O5 (Ln= Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho and Er were synthesized by hydrothermal synthesis in a single step and without subsequent thermal treatments from aqueous solutions of metals salts at 240 ºC. The obtained single crystals have a size of various micrometers and their morphology changes throughout the serie: they are polygonal in the case of the compounds with Ln= Pr, Nd, Sm, Eu and Gd and needle-like in the case of the compounds with Ln= Y, Tb, Dy, Ho and Er. After the analysis of the obtained products employing different conditions of synthesis we attributed the different morphology to a greater growth rate along the c axis when the smaller ions (Y, Tb, Dy, Ho y Er are involved, due to their better adaptation to the compound’s crystal structure.Se han conseguido preparar monocristales de 10 óxidos mixtos de la serie LnMn2O5 (Ln= Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho y Er mediante síntesis hidrotermal optimizada, en un único paso y sin tratamientos térmicos posteriores partiendo de las correspondientes sales metálicas en disolución acuosa a 240 ºC. Los monocristales obtenidos son relativamente grandes, de varias micras y su morfología varía a lo largo de la serie: es poligonal en el caso de los compuestos de los lantánidos del inicio de la serie (Ln= Pr, Nd, Sm, Eu y Gd y acicular en el caso de los compuestos de Y y de los lantánidos del final de la serie (Ln= Tb, Dy, Ho y Er. Tras el análisis de los productos obtenidos empleando distintas condiciones de síntesis atribuimos la diferente morfología a una mayor velocidad de crecimiento cristalino a lo largo del eje c cuando intervienen los iones más pequeños (Y, Tb, Dy, Ho y Er debido a la mejor adaptación de éstos últimos a la estructura cristalina del compuesto.

  10. Structural relative stabilities and pressure-induced phase transitions for lanthanide trihydrides REH{sub 3} (RE=Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu)

    Energy Technology Data Exchange (ETDEWEB)

    Kong Bo, E-mail: kong79@yeah.net [National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics, Chinese Academy of Engineering Physics, Mianyang 621900 (China); College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Zhang Lin, E-mail: zhanglinbox@263.net [National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics, Chinese Academy of Engineering Physics, Mianyang 621900 (China); Chen Xiangrong [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Zeng Tixian [College of Physics and Electronic Information, China West Normal University, Nanchong 637002 (China); Cai Lingcang [National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics, Chinese Academy of Engineering Physics, Mianyang 621900 (China)

    2012-06-15

    The structures, structural relative stabilities, pressure-induced phase transitions, and equations of state for lanthanide trihydrides REH{sub 3} (RE=Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu) are systematically studied using ab initio calculations under a core state model (CSM). The obtained ground-state parameters, such as lattice constants and bulk modulus, agree well with the available data. Among the P6{sub 3}/mm, P3-bar c1, and P6{sub 3}cm structures, the P6{sub 3}cm structure is found to be the most stable structure for lanthanide trihydride via the comparison of the calculated total energies. With the help of Birch-Murnaghan equation of state, the structural transitions from hexagonal to cubic for REH{sub 3} (RE=Sm, Gd, Ho, Er, and Lu) under pressure are affirmed; especially, the similar behavior of REH{sub 3} (RE= Tb, Dy, and Tm) is reasonably predicted for the first time by this means. For the transitions, the repulsive interactions of H-H atoms may play an important role in terms of the analysis of the structures in the vicinity of the theoretical phase transition.

  11. Synthesis under ambient pressure and tri-axial magnetic orientation in REBa2Cu4O8 (RE = Y, Sm, Eu, Gd, Dy, Ho, Er)

    International Nuclear Information System (INIS)

    Yamaki, M.; Horii, S.; Haruta, M.; Maeda, T.; Shimoyama, J.

    2011-01-01

    REBa 2 Cu 4 O 8 (RE124) was synthesized by a flux method in ambient pressure for RE = Y, Sm, Eu, Gd, Dy, Ho and Er. Tri-axial orientation of RE124 was achieved in a modulated rotating magnetic field of 10 T. Orientation axes in RE124 depended on the type of RE. Magnetization axes were determined from magnetic anisotropies of Cu and RE ions. We report the rare-earth (RE)-dependent magnetization axes of REBa 2 Cu 4 O 8 , which was synthesized by a flux method under ambient pressure, using powder samples tri-axially oriented in a modulated rotating magnetic field of 10 T. By optimizing the growth temperature and cooling rate, RE124 crystals were successfully grown for RE = Y, Sm, Eu, Gd, Dy, Ho, and Er. From the X-ray diffraction measurement, the magnetically oriented directions were largely dependent on the type of RE ions of RE124. However, the tri-axial magnetic anisotropies of RE124 could be qualitatively understood in terms of the magnitude relation between the single-ion magnetic anisotropy of RE 3+ ions and the magnetic anisotropy generated by the CuO 2 plane and Cu-O chain. For the practical use of this magneto-scientific process, the control of magnetization axes and tri-axial magnetic anisotropies through crystallochemical control is indispensable.

  12. Platinum triangles in the Pt/Al framework of the intermetallic REPt6Al3 (RE = Ce-Nd, Sm, Gd, Tb) series

    International Nuclear Information System (INIS)

    Eustermann, Fabian; Stegemann, Frank; Renner, Konstantin; Janka, Oliver

    2017-01-01

    The compounds of the REPt 6 Al 3 series (RE = Ce-Nd, Sm, Gd, Tb) were obtained by reaction of the elements via arc-melting. They were characterized by powder and single-crystal X-ray diffraction (NdPt 6 Al 3 : wR = 0.0432, 759 F 2 values, 33 variables) as well as by magnetic susceptibility measurements. The isostructural compounds crystallize with a new structure type in the trigonal crystal system with space group R anti 3c, twelve formula units in the unit cell, and lattice parameters of a = 752-755 and c = 3882-3945 pm. The crystal structure can be described by different slabs stacked along [001]. One layer features Pt 3 triangles, centering the cavities of a flat honeycomb RE layer that are arranged in a..ABCA ' B ' C ' .. sequence. The other layer consists of condensed hexagonal [Pt 6 Al 6 ] prisms, centered by Pt atoms, separating the before mentioned slabs. Magnetic measurements revealed that all rare-earth atoms are in the trivalent oxidation state, however, due to the low lanthanoide content magnetic ordering phenomena were observed only at low temperatures [SmPt 6 Al 3 : T C = 5.0(1) K; GdPt 6 Al 3 : T C = 7.3(1) K; TbPt 6 Al 3 : T N = 3.6(1) K]. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Determination of Debye temperatures and Lamb-Mössbauer factors for LnFeO3 orthoferrite perovskites (Ln  =  La, Nd, Sm, Eu, Gd)

    Science.gov (United States)

    Scrimshire, A.; Lobera, A.; Bell, A. M. T.; Jones, A. H.; Sterianou, I.; Forder, S. D.; Bingham, P. A.

    2018-03-01

    Lanthanide orthoferrites have wide-ranging industrial uses including solar, catalytic and electronic applications. Here a series of lanthanide orthoferrite perovskites, LnFeO3 (Ln  =  La Nd; Sm; Eu; Gd), prepared through a standard stoichiometric wet ball milling route using oxide precursors, has been studied. Characterisation through x-ray diffraction and x-ray fluorescence confirmed the synthesis of phase-pure or near-pure LnFeO3 compounds. 57Fe Mössbauer spectroscopy was performed over a temperature range of 10 K-293 K to observe hyperfine structure and to enable calculation of the recoil-free fraction and Debye temperature (θ D) of each orthoferrite. Debye temperatures (Ln  =  La 474 K Nd 459 K Sm 457 K Eu 452 K Gd 473 K) and recoil-free fractions (Ln  =  La 0.827; Nd 0.817; Sm 0.816; Eu 0.812; Gd 0.826) were approximated through minimising the difference in the temperature dependent experimental centre shift and theoretical isomer shift, by allowing the Debye temperature and isomer shift values to vary. This method of minimising the difference between theoretical and actual values yields Debye temperatures consistent with results from other studies determined through thermal analysis methods. This displays the ability of variable-temperature Mössbauer spectroscopy to approximate Debye temperatures and recoil-free fractions, whilst observing temperature induced transitions over the temperature range observed. X-ray diffraction and Rietveld refinement show an inverse relationship between FeO6 octahedral volume and approximated Debye temperatures. Raman spectroscopy show an increase in the band positions attributed to soft modes of Ag symmetry, Ag(3) and Ag(5) from La to GdFeO3 corresponding to octahedral rotations and tilts in the [0 1 0] and [1 0 1] planes respectively.

  14. Symmetry-Breaking Transitions in RECuAs2-xPx (RE=Sm, Gd, Ho, and Er)

    Energy Technology Data Exchange (ETDEWEB)

    Mozharivskyj, Yurij [Iowa State Univ., Ames, IA (United States)

    2002-01-01

    Structural changes resulting in lower symmetries can be understood in terms of electronic instabilities and Coulomb interactions. The interplay of these two interrelated factors is complicated and difficult to analyze. The RECuAs2-xP x phases, because of the variation in the chemical content (As/P substitution), allow, with the aid of band structures, Madelung energies and Landau theory, a partial unraveling of the forces important in the symmetry-breaking transitions in RECuAs2-xP x (RE = Sm, Gd, Ho and Er). Distortions of the P layers in SmCu1.15P2, GdCuP2.20 and ErCuP2 are usefully thought of as generalized Peierls distortions, i.e., they lower the electronic (and total) energy and lead to more stable structures. On the other hand, the P4/nmm → Pmmn transitions, which are observed in all studied arsenophosphide series and occur upon substitution of P for As, originate from the B1g vibrational mode and are structural adaptations to smaller P atoms. These transitions provide tighter atomic packing and better Coulomb interactions. Configurational contribution to the entropy becomes important in stabilizing the mixed occupancy in the RECuAs 2-xP x arsenophosphides. While geometric and electronic factors favor separation of the As and P atoms over two different crystallographic sites, configurational entropy stabilizes the As/P mixing on these two sites.;Progress in the research on RECuAs2-xP x was dependent upon the ability of Landau theory to predict, explain and dismiss structural models and transitions. The space group Pmmn (arising from the B 1g vibrational mode) in all mixed arsenophosphides and the existence of these mixed arsenophosphides followed from the analysis of GdCuAs 2 and GdCuP2, using Landau theory. The impossibility of obtaining the high-symmetry structure (P4/nmm) and the low symmetry structure

  15. First-principles calculation of structural and energetic properties for A2Ti2O7 (A = Lu, Er, Y, Gd, Sm, Nd, La)

    International Nuclear Information System (INIS)

    Zhang, Z.L.; Xiao, H.Y.; Zu, Xiaotao T.; Gao, Fei; Weber, William J.

    2009-01-01

    A first-principles method has been employed to investigate the structural and energetic properties for A2Ti2O7 (A = Lu, Er, Y, Gd, Sm, Nd, La), including the formation energies of the cation antisite-pair, the anion Frenkel pair that defines anion-disorder, and the coupled cation antisite-pair/anion-Frenkel. It is proposed that the interaction may have more significant influence on the radiation resistance behavior of titanate pyrochlores, although the interactions are relatively much stronger than the interactions. It is found that the defect formation energies are not simple functions of the A-site cation radii. The formation energy of the cation antisite-pair increases continuously as the A-site cation varies from Lu to Gd, and then decreases continuously with the variation of the A-site cation from Gd to La, in excellent agreement with the radiation-resistance trend of the titanate pyrochlores. The band gaps in these pyrochlores were also measured, and the band gap widths changed continuously with cation radius.

  16. Electric and magnetic properties of Al{sub 86}Ni{sub 8}R{sub 6} (R=Sm, Gd, Ho) alloys in liquid and amorphous states

    Energy Technology Data Exchange (ETDEWEB)

    Sidorov, V. [Ural State Pedagogical University, Ekaterinburg (Russian Federation); Ural Federal University, Ekaterinburg (Russian Federation); Svec, P.; Svec, P.; Janickovic, D. [Institute of Physics SAS, Bratislava (Slovakia); Mikhailov, V. [Ural State Pedagogical University, Ekaterinburg (Russian Federation); Sidorova, E. [Plekhanov Russian University of Economics, Moscow (Russian Federation); Son, L. [Ural State Pedagogical University, Ekaterinburg (Russian Federation); Ural Federal University, Ekaterinburg (Russian Federation)

    2016-06-15

    Electrical resistivity and magnetic susceptibility of Al{sub 86}Ni{sub 8}Sm{sub 6}, Al{sub 86}Ni{sub 8}Gd{sub 6} and Al{sub 86}Ni{sub 8}Ho{sub 6} alloys are studied in a wide temperature range including amorphous, crystalline and liquid states. The negative value of resistivity temperature coefficient in amorphous ribbons is explained by the structural separation starting much before the beginning of their crystallization. The effective magnetic moments per Gd and Ho atoms are found to be essentially lower than for R{sup 3+} ions. The results are discussed in supposition of directed bonds between rare earth and aluminum atoms. - Highlights: • Electric and magnetic properties of Al{sub 86}Ni{sub 8}R{sub 6} alloys are studied experimentally. • The negative value of rtc in amorphous ribbons is explained. • The effective magnetic moments per Gd and Ho are found to be lower than for R{sup 3+} ions.

  17. Tune color of single-phase LiGd(MoO4)2-X(WO4)X: Sm3+, Tb3+ via adjusting the proportion of matrix and energy transfer to create white-light phosphor

    Science.gov (United States)

    Wu, Hongyue; Yang, Junfeng; Wang, Xiaoxue; Gan, Shucai; Li, Linlin

    2018-03-01

    A series of LiGd(MO4)2: Sm3+, Tb3+ (M = Mo, W) phosphors was prepared by a conventional solid state reaction method. Powder X-Ray diffraction (XRD) analysis reveals that the compounds are of the same structure type. Their luminescent properties have been studied. The optimal doping concentrations are 8% for Sm3+ and 18% for Tb3+ in the LiGd(MoO4)2 host. Sm3+ and Tb3+ have different sensitivity to the Mo/W ratio. For LiGd(MoO4)2-X(WO4)X: Sm3+ (X = 0, 0.4, 0.8, 1.2, 1.6, 2.0), the strongest emission intensity is 1.766 times than that of the weakest, while 171 times for LiGd(MoO4)2-X(WO4)X: Tb3+. The experimental results show that Mo/W ratio strong influences on the properties of LiGd(MoO4)2-X(WO4)X: Tb3+. With the increasing of WO42- groups concentration, the shape of characteristic excitation peaks of Tb3+ is almost the same and the excitation intensity gradually increase. Moreover, the energy transfer from Tb3+ to Sm3+ has been realized in the co-doped phosphors. The experimental analysis and theoretical calculations reveal that the quadrupole-quadrupole interaction is the dominant mechanism for the Tb3+→Sm3+ energy transfer. Therefore, luminous intensity can be adjusted by different sensitivities to matrix composition and energy transfer from Tb3+→Sm3+. By this tuning color method, white-light-emitting phosphor has been prepared. The excitation wavelength is 378 nm, and this indicates that the white-light-emitting phosphor could be pumped by near-UV light.

  18. Solubility and superconductivity in RE(Ba2-xREx)Cu3O7+δ (RE = Nd, Sm, Eu, Gd, Dy)

    International Nuclear Information System (INIS)

    Zhang, K.; Dabrowski, B.; Segre, C.U.; Hinks, D.G.; Schuller, I.K.; Jorgensen, J.D.; Slaski, M.

    1987-10-01

    Solid solutions of RE(Ba 2-x RE x )Cu 3 O 7- δ (RE=Nd,Sm,Eu,Gd,Dy) for x=0 to x=0.5 have been investigated. X-ray and resistivity measurements show that there exists a solid solution region, through which, the structure changes from orthorhombic to tetragonal and the superconducting properties are depressed. The solubility limits depend strongly on the size of the rare-earth ion, with the smallest (Dy) showing no appreciable solubility. The superconducting transition temperature versus x for all of the rare-earth ion substitutions falls on a universal curve, indicating that the Ba sites are extremely ionic and magnetically isolated. 20 refs., 4 figs

  19. X-ray spectroscopic and magnetic studies of RBaCo_2O_5_._5, R = Pr, Nd, Sm, Gd and Y

    International Nuclear Information System (INIS)

    Ganorkar, S.; Priolkar, K. R.; Sarode, P. R.; Emura, S.

    2016-01-01

    The structural and magnetic properties of layered perovskites of the type RBaCo_2O_5_+_δ with δ ≤0.5 (R=Pr, Nd, Sm, Gd and Y) have been investigated. The samples were prepared by the sol-gel method and characterized by X-ray diffraction, magnetization and X-ray absorption near edge structure (XANES) spectroscopy. It is found that the magnetic properties depend on the size of the rare-earth ion. The critical size of the rare-earth ion introduces structural distortion which affects the Co-O hybridization in these layered perovskites. The detailed analysis of experimental and calculated XANES spectra throws some light on spin states of Co ions in these perovskites.

  20. State-of-the-art flux pinning in YBa2Cu3O7-δ by the creation of highly linear, segmented nanorods of Ba2(Y /Gd)(Nb/Ta)O6 together with nanoparticles of (Y /Gd)2O3 and (Y /Gd)Ba2Cu4O8

    International Nuclear Information System (INIS)

    Ercolano, G; Bianchetti, M; Wimbush, S C; Harrington, S A; MacManus-Driscoll, J L; Wang, H; Lee, J H

    2011-01-01

    Self-assembled, segmented nanorods of c-axis-aligned Ba 2 (Y /Gd)(Nb/Ta)O 6 as well as randomly distributed nanoparticles of (Y /Gd) 2 O 3 and (Y /Gd)Ba 2 Cu 4 O 8 were grown into YBa 2 Cu 3 O 7-δ (YBCO) thin films by pulsed-laser deposition. The complex pinning landscape proves to be extremely effective, particularly at higher fields where the segmented vortices yield a plateau in critical current density (J c ) with field angle around 60 0 . In 0.3 μm thick films, the J c values are higher than 1 MA cm -2 at 2.5 T (H||c axis). Owing to the combined interactions of the vortices with the different pinning centres, interesting new features are observed at high fields in the angular dependence of J c .

  1. Magnetic properties of the germanides RE{sub 3}Pt{sub 4}Ge{sub 6} (RE=Y, Pr, Nd, Sm, Gd-Dy)

    Energy Technology Data Exchange (ETDEWEB)

    Eustermann, Fabian; Eilers-Rethwisch, Matthias; Renner, Konstantin; Hoffmann, Rolf-Dieter; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Janka, Oliver [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Oldenburg Univ. (Germany). Inst. fuer Chemie

    2017-07-01

    The germanides RE{sub 3}Pt{sub 4}Ge{sub 6} (RE=Y, Pr, Nd, Sm, Gd-Dy) have been synthesized by arc-melting of the elements followed by inductive annealing to improve the crystallinity and allow for structural order. The compounds have been studied by powder X-ray diffraction; additionally the structure of Y{sub 3}Pt{sub 4}Ge{sub 6} has been refined from single-crystal X-ray diffractometer data. It exhibits a (3+1)D modulated structure, indicating isotypism with Ce{sub 3}Pt{sub 4}Ge{sub 6}. The crystal structure can be described as an intergrowth between YIrGe{sub 2}- and CaBe{sub 2}Ge{sub 2}-type slabs along [100]. Temperature-dependent magnetic susceptibility measurements showed Pauli paramagnetism for Y{sub 3}Pt{sub 4}Ge{sub 6} and Curie-Weiss paramagnetism for Pr{sub 3}Pt{sub 4}Ge{sub 6} and Nd{sub 3}Pt{sub 4}Ge{sub 6}. Sm{sub 3}Pt{sub 4}Ge{sub 6} exhibits van Vleck paramagnetism, while antiferromagnetic ordering at T{sub N}=8.1(1) K and T{sub N}=11.0(1) K is observed for Gd{sub 3}Pt{sub 4}Ge{sub 6} and Tb{sub 3}Pt{sub 4}Ge{sub 6}, respectively.

  2. Platinum triangles in the Pt/Al framework of the intermetallic REPt{sub 6}Al{sub 3} (RE = Ce-Nd, Sm, Gd, Tb) series

    Energy Technology Data Exchange (ETDEWEB)

    Eustermann, Fabian; Stegemann, Frank; Renner, Konstantin [Institut fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Universitaet Muenster (Germany); Janka, Oliver [Institut fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Universitaet Muenster (Germany); Institut fuer Chemie, Carl von Ossietzky Universitaet Oldenburg (Germany)

    2017-12-13

    The compounds of the REPt{sub 6}Al{sub 3} series (RE = Ce-Nd, Sm, Gd, Tb) were obtained by reaction of the elements via arc-melting. They were characterized by powder and single-crystal X-ray diffraction (NdPt{sub 6}Al{sub 3}: wR = 0.0432, 759 F{sup 2} values, 33 variables) as well as by magnetic susceptibility measurements. The isostructural compounds crystallize with a new structure type in the trigonal crystal system with space group R anti 3c, twelve formula units in the unit cell, and lattice parameters of a = 752-755 and c = 3882-3945 pm. The crystal structure can be described by different slabs stacked along [001]. One layer features Pt{sub 3} triangles, centering the cavities of a flat honeycomb RE layer that are arranged in a..ABCA{sup '}B{sup '}C{sup '}.. sequence. The other layer consists of condensed hexagonal [Pt{sub 6}Al{sub 6}] prisms, centered by Pt atoms, separating the before mentioned slabs. Magnetic measurements revealed that all rare-earth atoms are in the trivalent oxidation state, however, due to the low lanthanoide content magnetic ordering phenomena were observed only at low temperatures [SmPt{sub 6}Al{sub 3}: T{sub C} = 5.0(1) K; GdPt{sub 6}Al{sub 3}: T{sub C} = 7.3(1) K; TbPt{sub 6}Al{sub 3}: T{sub N} = 3.6(1) K]. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Ln28Ti2O7 (Ln = La, Nd, Sm, Gd): a novel series of defective Ruddlesden–Popper phases formed by topotactic dehydration of HLnTiO4

    OpenAIRE

    Thangadurai, V; Subbanna, GN; Gopalakrishnan, J

    1998-01-01

    Topotactic dehydration of HLnTiO4 (Ln = La, Nd, Sm or Gd) around 480–500 °C yields a new series of metastable layered perovskite oxides, Ln28Ti2O7, that possess a defective Sr3Ti2O7 structure, where the cubooctahedral sites within the double-perovskite layers are most likely vacant.

  4. Fission of Al, Ti, Co, Zr, Nb, Ag, In, Nd, Sm, and Ta nuclei induced by 0.8-1.8 GeV photons

    International Nuclear Information System (INIS)

    Lima, D.A. de; Martins, J.B.; Tavares, O.A.P.

    1989-01-01

    Samples of Al, Ti, Co, Zr, Nb, Ag, In, Nd, Sm, and Ta elements in contact with solid state nuclear track detectors were exposed to 0.8-1.8 GeV bremsstrahlung beams at the 2.5-GeV Electron Synchrotron of the Bonn University. The detectors were processed to produce visible fission tracks for track analysis with optical microscopes. Absolute mean cross section per photon and fissility were evaluated. Results are discussed and compared with other photofission data as well as with estimates from the current fission models. A broad minimum found for nuclear fissility of 10 -4 -10 -3 covering the range 15 approx Z 2 /A approx 25 seems to confirm the predictions from the models. For Al and Ti nuclei the probability of fission amounts to approx 10 -1 . (author) [pt

  5. Formation constants of Sm(III), Dy(III), Gd(III), Pr(III) and Nd(III) complexes of tridentate schiff base, 2-[(1H-benzimidazol-2-yl-methylene) amino] phenol

    International Nuclear Information System (INIS)

    Omprakash, K.L.; Chandra Pal, A.V.; Reddy, M.L.N.

    1982-01-01

    A new tridentate schiff base, 2- (1H-benzimidazol-2-yl-methylene)amino phenol derived from benzimididazole-2-carbo-xaldehyde and 2-aminophenol has been synthesised and characterised by spectral and analytical data. Proton-ligand formation constants of the schiff base and metal-ligand formation constants of its complexes with Sm(III), Dy(III), Gd(III), Nd(III) and Pr(III) have been determined potentiometrically in 50% (v/v) aqueous dioxane at an ionic strength of 0.1M (NaClO 4 ) and at 25deg C using the Irving-Rossotti titration technique. The order of stability constants (logβ 2 ) is found to be Sm(III)>Dy(III)>Gd(III)>Pr(III)>Nd(III). (author)

  6. Formation constants of Sm(III), Dy(III), Gd(III), Pr(III) and Nd(III) complexes of tridentate schiff base, 2-((1H-benzimidazol-2-yl-methylene) amino) phenol

    Energy Technology Data Exchange (ETDEWEB)

    Omprakash, K L; Chandra Pal, A V; Reddy, M L.N. [Osmania Univ., Hyderabad (India). Dept. of Chemistry

    1982-03-01

    A new tridentate schiff base, 2- (1H-benzimidazol-2-yl-methylene)amino phenol derived from benzimididazole-2-carbo-xaldehyde and 2-aminophenol has been synthesised and characterised by spectral and analytical data. Proton-ligand formation constants of the schiff base and metal-ligand formation constants of its complexes with Sm(III), Dy(III), Gd(III), Nd(III) and Pr(III) have been determined potentiometrically in 50% (v/v) aqueous dioxane at an ionic strength of 0.1M (NaClO/sub 4/) and at 25deg C using the Irving-Rossotti titration technique. The order of stability constants (log..beta../sub 2/) is found to be Sm(III)>Dy(III)>Gd(III)>Pr(III)>Nd(III).

  7. Study of LnBaCo{sub 2}O{sub 6-d}elta (Ln = Pr, Nd, Sm and Gd) double perovskites as new cathode material for IT-SOFC

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, E; Mueller, M; Mogni, L; Caneiro, A, E-mail: mogni@cab.cnea.gov.a [Centro Atomico Bariloche-CNEA, Instituto Balseiro. Av. Bustillo 9500, S. C. de Bariloche 8400 (Argentina)

    2009-05-01

    Oxides with double perovskites structures of general composition LnBaCo{sub 2}O{sub 6-d}elta (Ln = Pr, Nd, Sm and Gd) were synthesized by solid state reaction with the purpose to evaluate new materials to be used as cathodes in intermediate temperature solid oxide fuel cell (IT-SOFC). A preliminary study about electrochemical properties was performed by impedance spectroscopy between 500 and 800 deg. C under atmosphere of pure O{sub 2}. Symmetrical cells were obtained by spray deposition of LnBaCo{sub 2}O{sub 6-d}elta (Ln = Pr, Nd, Sm and Gd) at both sides of a dense ceramic electrolyte. The impedance spectroscopy measurements as a function of temperatures show a hysteresis loop which could be associated to a tetragonal/orthorhombic phase transition. The existence of this transition was corroborated by high temperature X-Ray diffraction and Differential Scanning Calorimetry measurements.

  8. Rare earth elements in the Pacific and Atlantic Oceans. [Pr, Tb, Ho, Tm, Lu, La, Nd, Sm, Eu, Gd, Yb, Ce

    Energy Technology Data Exchange (ETDEWEB)

    Baar, H J.W. de; Bacon, M P; Brewer, P G; Bruland, K W

    1985-09-01

    The first profiles of Pr, Tb, Ho, Tm and Lu in the Pacific Ocean, as well as profiles of La, Ce, Nd, Sm, Eu, Gd and Yb are reported. Concentrations of REE (except Ce) in the deep water are two to three times higher than those observed in the deep Atlantic Ocean. Surface water concentrations are typically lower than in the Atlantic Ocean, especially for the heavier elements Ho,Tm,Yb and Lu. Cerium is strongly depleted in the Pacific water column, but less so in the oxygen minimum zone. The distribution of the REE group is consistent with two simultaneous processes: (1) cycling similar to that of opal and calcium carbonate, and (2) adsorptive scavenging by settling particles and possibly by uptake at ocean boundaries. However, the first process can probably not be sustained by the low REE contents of shells, unless additional adsorption on surfaces is invoked. The second process, adsorptive scavenging, largely controls the oceanic distribution and typical seawater pattern of the rare earths. (author).

  9. Angular non-critical phase-matching second-harmonic-generation characteristics of RECOB (RE = Tm, Y, Gd, Sm, Nd and La) crystals.

    Science.gov (United States)

    Liu, Yanqing; Wang, Zhengping; Yu, Fapeng; Qi, Hongwei; Yang, Xiuqin; Yu, Xiaoqiang; Zhao, Xian; Xu, Xinguang

    2017-05-15

    For the first time, the angular non-critical phase-matching (A-NCPM) second-harmonic-generation (SHG) characteristics of a family of monoclinic oxoborate crystals, RECa 4 O(BO 3 ) 3 (RECOB, RE = Tm, Y, Gd, Sm, Nd and La), were comprehensively investigated. For all of the realizable A-NCPM SHG styles, the feature parameters including PM wavelength, angular, wavelength and temperature acceptance bandwidths, have been derived from the theory and verified by the experiments. We discovered that the closer the ion radius between RE 3+ and Ca 2+ , the smaller the birefringence, and the better the A-NCPM SHG properties. As a result, for the Type-I SHG on Y-axis which has the largest effective nonlinear optical coefficient (d eff ) among the three realizable A-NCPM styles, NdCOB crystal presents the longest PM wavelength (927 nm), the largest angular acceptance bandwidth (Δθ⋅l 1/2 = 84.3 mrad·cm 1/2 , Δϕ⋅l 1/2 = 58.8 mrad·cm 1/2 ), and the broadest wavelength acceptance bandwidth (8.7 nm). This discovery will contribute to the design of new NCPM materials, at the same time the parameter formula will be helpful for the theoretical prediction of NCPM performance.

  10. Charge disproportionation in (X0.6Sr0.4)0.99Fe0.8Co0.2O3-δ perovskites (X = La, Pr, Sm, Gd)

    DEFF Research Database (Denmark)

    Pedersen, Thomas; Saadi, Souheil; Nielsen, K.H.

    2005-01-01

    The change in crystal structure and the oxidation state in iron of iron-cobalt-based perovskites with different A-site cations is investigated by the use of powder XRD and Mossbauer spectroscopy. The perovskites investigated are (X0.6Sr0.4)(0.99)Fe0.8Co0.2O3-delta, where X is La, Pr, Sm or Gd...

  11. An analysis on structural and magnetic properties of La{sub 1-x}RE{sub x}FeO{sub 3} (x = 0.0 and 0.5, RE = Nd, Sm and Gd) nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Blessington Selvadurai, A. Paul; Pazhanivelu, V.; Jagadeeshwaran, C.; Murugaraj, R. [Anna University, Department of Physics, Chennai (India); Gazzali, P.M. Mohammed; Chandrasekaran, G. [Pondicherry University, Department of Physics, Pudhucherry (India)

    2017-01-15

    La{sub 1-x}RE{sub x}FeO{sub 3} (x = 0.0 and 0.5, RE = Nd, Sm and Gd) is synthesised by sol-gel citrate combustion method. X-ray diffraction (XRD) and Raman spectra show orthorhombic phase with Pbnm symmetry, confirmed by profile fitting and Raman modes analysis for La{sub 1-x}R{sub x}FeO{sub 3} samples. The estimated crystallite size and the orthorhombic strain of La{sub 1-x}RE{sub x}FeO{sub 3} (x = 0.0 and 0.5, RE = Nd, Sm and Gd) from XRD data illustrate the role of ionic size substitution. The temperature- and field-dependent magnetisation M(T) and M(H) were measured using vibrating sample magnetometer. The M(H) curve parameters of La{sub 1-x}RE{sub x}FeO{sub 3}(x = 0.5, RE = Nd and Gd) exhibit a relation of M{sub r} ∝ (1)/(H{sub c}) and H{sub ex} ∝ H{sub C} at 20, 150 and 300 K. The M (T) curve of La{sub 0.5}Nd{sub 0.5}FeO{sub 3} and La{sub 0.5}Gd{sub 0.5}FeO{sub 3} indicates the paramagnetic-like behaviour, whereas the M (H) curve reveals the antiferromagnetic signature in them. The M (H) curve of La{sub 0.5}Sm{sub 0.5}FeO{sub 3} shows a strong AFM pinned ferromagnetism and ferromagnetism (FM) at 150 and 20 K, respectively. Further, field-cooled (FC) and zero-field-cooled (ZFC) measurement of La{sub 0.5}Sm{sub 0.5}FeO{sub 3} indicates a competitive interaction of AFM-FM, which is emphasised by a broad blocking temperature at ∝117 K in ZFC curve. The FM-like ordering of Sm{sup 3+} ions are observed below at ∝150 K in FC curve of La{sub 0.5}Sm{sub 0.5}FeO{sub 3}. In addition, the electron paramagnetic resonance spectra at room temperature show a high g value and a strong non-homogenous broadening for La{sub 0.5}Sm{sub 0.5}FeO{sub 3}. (orig.)

  12. Ion-irradiation resistance of the orthorhombic Ln_2TiO_5 (Ln = La, Pr, Nd, Sm, Eu, Gd, Tb and Dy) series

    International Nuclear Information System (INIS)

    Aughterson, Robert D.; Lumpkin, Gregory R.; Ionescu, Mihail; Reyes, Massey de los; Gault, Baptiste; Whittle, Karl R.; Smith, Katherine L.; Cairney, Julie M.

    2015-01-01

    The response of Ln_2TiO_5 (where Ln is a lanthanide) compounds exposed to high-energy ions was used to test their suitability for nuclear-based applications, under two different but complementary conditions. Eight samples with nominal stoichiometry Ln_2TiO_5 (Ln = La, Pr, Nd, Sm, Eu, Gd, Tb and Dy), of orthorhombic (Pnma) structure were irradiated, at various temperatures, with 1 MeV Kr"2"+ ions in-situ within a transmission electron microscope. In each case, the fluence was increased until a phase transition from crystalline to amorphous was observed, termed critical dose D_c. At certain elevated temperatures, the crystallinity was maintained irrespective of fluence. The critical temperature for maintaining crystallinity, T_c, varied non-uniformly across the series. The T_c was consistently high for La, Pr, Nd and Sm_2TiO_5 before sequential improvement from Eu to Dy_2TiO_5 with T_c's dropping from 974 K to 712 K. In addition, bulk Dy_2TiO_5 was irradiated with 12 MeV Au"+ ions at 300 K, 723 K and 823 K and monitored via grazing-incidence X-ray diffraction (GIXRD). At 300 K, only amorphisation is observed, with no transition to other structures, whilst at higher temperatures, specimens retained their original structure. The improved radiation tolerance of compounds containing smaller lanthanides has previously been attributed to their ability to form radiation-induced phase transitions. No such transitions were observed here. - Highlights: • First ion-irradiation studies on a number of novel compounds including Pr_2TiO_5, Eu_2TiO_5 and Tb_2TiO_5. • Systematic in-situ ion-irradiation study of almost complete Ln_2TiO_5 series (Ln = lanthanides) with orthorhombic crystal structure type. • The first grazing incidence study of bulk irradiated Dy_2TiO_5 looking for irradiation induced phase transition.

  13. General synthesis and structural evolution of a layered family of Ln8(OH)20Cl4 x nH2O (Ln = Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Y).

    Science.gov (United States)

    Geng, Fengxia; Matsushita, Yoshitaka; Ma, Renzhi; Xin, Hao; Tanaka, Masahiko; Izumi, Fujio; Iyi, Nobuo; Sasaki, Takayoshi

    2008-12-03

    The synthesis process and crystal structure evolution for a family of stoichiometric layered rare-earth hydroxides with general formula Ln(8)(OH)(20)Cl(4) x nH(2)O (Ln = Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Y; n approximately 6-7) are described. Synthesis was accomplished through homogeneous precipitation of LnCl(3) x xH(2)O with hexamethylenetetramine to yield a single-phase product for Sm-Er and Y. Some minor coexisting phases were observed for Nd(3+) and Tm(3+), indicating a size limit for this layered series. Light lanthanides (Nd, Sm, Eu) crystallized into rectangular platelets, whereas platelets of heavy lanthanides from Gd tended to be of quasi-hexagonal morphology. Rietveld profile analysis revealed that all phases were isostructural in an orthorhombic layered structure featuring a positively charged layer, [Ln(8)(OH)(20)(H(2)O)(n)](4+), and interlayer charge-balancing Cl(-) ions. In-plane lattice parameters a and b decreased nearly linearly with a decrease in the rare-earth cation size. The interlamellar distance, c, was almost constant (approximately 8.70 A) for rare-earth elements Nd(3+), Sm(3+), and Eu(3+), but it suddenly decreased to approximately 8.45 A for Tb(3+), Dy(3+), Ho(3+), and Er(3+), which can be ascribed to two different degrees of hydration. Nd(3+) typically adopted a phase with high hydration, whereas a low-hydration phase was preferred for Tb(3+), Dy(3+), Ho(3+), Er(3+), and Tm(3+). Sm(3+), Eu(3+), and Gd(3+) samples were sensitive to humidity conditions because high- and low-hydration phases were interconvertible at a critical humidity of 10%, 20%, and 50%, respectively, as supported by both X-ray diffraction and gravimetry as a function of the relative humidity. In the phase conversion process, interlayer expansion or contraction of approximately 0.2 A also occurred as a possible consequence of absorption/desorption of H(2)O molecules. The hydration difference was also evidenced by refinement results. The number of coordinated water

  14. Ternary rhombohedral Laves phases RE{sub 2}Rh{sub 3}Ga (RE = Y, La-Nd, Sm, Gd-Er)

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, Stefan; Benndorf, Christopher; Heletta, Lukas; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Janka, Oliver [Oldenburg Univ. (Germany). Inst. fuer Chemie; Mausolf, Bernhard [RWTH Aachen (Germany). Inst. fuer Anorganische Chemie; Haarmann, Frank [RWTH Aachen (Germany). Inst. fuer Anorganische Chemie; Max-Planck-Institut fuer Chemische Physik fester Stoffe, Dresden (Germany); Eckert, Hellmut [Muenster Univ. (Germany). Inst. fuer Physikalische Chemie; Sao Paulo Univ., Sao Carlos (Brazil). Inst. of Physics

    2017-06-01

    The ordered Laves phases RE{sub 2}Rh{sub 3}Ga (RE=Y, La-Nd, Sm, Gd-Er) were synthesized by arc-melting of the elements and subsequent annealing. The samples were characterized by powder X-ray diffraction (XRD). They crystallize with the rhombohedral Mg{sub 2}Ni{sub 3}Si type structure, space group R3m. Three structures were refined from single crystal X-ray diffractometer data: a=557.1(1), c=1183.1(2), wR2=0.0591, 159 F{sup 2} values, 10 variables for Y{sub 2}Rh{sub 3}Ga, a=562.5(2), c=1194.4(2) pm, wR2=0.0519, 206 F{sup 2} values, 11 variables for Ce{sub 2}Rh{sub 3}Ga and a=556.7(2), c=1184.1(3) pm, wR2=0.0396, 176 F{sup 2} values, 11 variables for Tb{sub 2}Rh{sub 3}Ga. The Rh{sub 3}Ga tetrahedra are condensed via common corners and the large cavities left by the network are filled by the rare earth atoms. The RE{sub 2}Rh{sub 3}Ga Laves phases crystallize with a translationengleiche subgroup of the cubic RERh{sub 2} Laves phases with MgCu{sub 2} type. Magnetic susceptibility measurements reveal Pauli paramagnetism for Y{sub 2}Rh{sub 3}Ga and La{sub 2}Rh{sub 3}Ga. Ce{sub 2}Rh{sub 3}Ga shows intermediate cerium valence while all other RE{sub 2}Rh{sub 3}Ga phases are Curie-Weiss paramagnets which order magnetically at low temperatures. The {sup 89}Y and {sup 71}Ga solid state nuclear magnetic resonance (NMR) spectra of the diamagnetic representative Y{sub 2}Rh{sub 3}Ga show well-defined single resonances in agreement with an ordered bulk phase. In comparison to the binary Laves phase YRh{sub 2} a strongly increased {sup 89}Y resonance frequency is observed owing to a higher s-electron spin density at the {sup 89}Y nuclei as proven by density of states (DOS) calculations.

  15. Photoluminescence and cathodoluminescence properties of Sr{sub 2}Gd{sub 8}Si{sub 6}O{sub 26}:RE{sup 3+}(RE{sup 3+}=Tb{sup 3+}or Sm{sup 3+}) phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, Sk. Khaja [Department of Electronics and Radio Engineering, Kyung Hee University, 1 Seocheon-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-701 (Korea, Republic of); Rao, Gattupalli Manikya [Department of Physics, College of Science and Technology, Andhra University, Visakhapatanam, Andhra Pradesh 53003 (India); Raju, G. Seeta Rama; Krishna Bharat, L. [Department of Electronics and Radio Engineering, Kyung Hee University, 1 Seocheon-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-701 (Korea, Republic of); Subba Rao, P.S.V., E-mail: raopsvs@rediffmail.com [Department of Physics, College of Science and Technology, Andhra University, Visakhapatanam, Andhra Pradesh 53003 (India); Yu, Jae Su, E-mail: jsyu@khu.ac.kr [Department of Electronics and Radio Engineering, Kyung Hee University, 1 Seocheon-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-701 (Korea, Republic of)

    2016-10-15

    Trivalent terbium (Tb{sup 3+}) or samarium (Sm{sup 3+}) ions individually activated green and orange emitting Sr{sub 2}Gd{sub 8}Si{sub 6}O{sub 26} (SGSO) phosphors were synthesized by a citrate sol–gel method. The X-ray diffraction patterns of SGSO:Tb{sup 3+} and SGSO:Sm{sup 3+} phosphors exhibited the characteristic diffraction peaks of oxyapatite in a hexagonal lattice structure. The photoluminescence (PL) properties at ultraviolet (UV) or near-UV excitation wavelengths were measured for Tb{sup 3+} or Sm{sup 3+} ions doped SGSO phosphors as a function of its respective concentration. The PL spectra of SGSO:Tb{sup 3+} phosphors revealed the characteristic emission peaks of both Gd{sup 3+} and Tb{sup 3+} ions which are associated with 4f–4f transitions under 274 nm of excitation wavelength. When the concentration of Tb{sup 3+} ions increased over 0.05 mol (5 mol%), the emission intensities of {sup 5}D{sub 3} transitions decreased due to the well-known cross-relaxation process. However, based on the intensities of {sup 5}D{sub 4} transitions, the optimum concentration of Tb{sup 3+} ions was found to be 0.05 mol. Under 404 nm of excitation wavelength, the SGSO:Sm{sup 3+} phosphors exhibited the characteristic orange emission at 600 nm due to the {sup 4}G{sub 5/2}→{sup 6}H{sub 7/2} electronic transition. The optimum concentration of SGSO:Sm{sup 3+} phosphors was found to be 0.02 mol. The decay curves of the optimized SGSO:Tb{sup 3+} and SGSO:Sm{sup 3+} phosphors were well fitted to single exponential functions and their lifetimes were calculated. Furthermore, the optimized phosphor samples showed good thermal stability. Likewise, cathodoluminescence properties were also studied for the optimized samples as a function of filament current and accelerating voltage. The Commission International de I-Eclairage chromaticity coordinates were calculated for the SGSO:Tb{sup 3+} and SGSO:Sm{sup 3+} phosphors.

  16. β-Y(BO{sub 2}){sub 3}. A new member of the β-Ln(BO{sub 2}){sub 3} (Ln = Nd, Sm, Gd-Lu) structure family

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, Martin K.; Huppertz, Hubert [Innsbruck Univ. (Austria). Inst. fuer Allgemeine, Anorganische und Theoretische Chemie

    2017-07-01

    β-Y(BO{sub 2}){sub 3} was synthesized in a Walker-type multianvil module at 5.9 GPa/1000 C. The crystal structure has been elucidated through single-crystal X-ray diffraction. β-Y(BO{sub 2}){sub 3} crystallizes in the orthorhombic space group Pnma (no. 62) with the lattice parameters a = 15.886(2), b = 7.3860(6), and c = 12.2119(9) Aa. Its crystal structure will be discussed in the context of the isotypic lanthanide borates β-Ln(BO{sub 2}){sub 3} (Ln = Nd, Sm, Gd-Lu).

  17. Complexes of o-Vanillin oxime with La(III), Ce(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III), Ho(III) and Yb(III)

    International Nuclear Information System (INIS)

    Dhar, M.L.; Gupta, V.K.; Singh, Onkar

    1988-01-01

    Ten complexes of lanthanides with o-vanillin oxime have been swynthesised and characterised. The composition of the complexes as determined by elemental and thermal analyses, infrared electronic spectral and magnetic moment studies is [Ln(C 8 H 8 NO 3 ) 3 .XH 2 O], where X=2 when Ln=La, Ce, Pr, Nd, Sm and X=3 when Ln=Gd, Dy, Tb, Ho, Yb; C 8 H 8 NO 3 - represents the anion of the ligand. (author). 16 refs., 2 figs., 2 tables

  18. Magnetization fluctuation analysis and superconducting parameters of La0.5RE0.5BaCaCu3O7-δ(RE=Y, Sm, Gd, Dy, Ho, Yb) superconductor

    International Nuclear Information System (INIS)

    Parra Vargas, C.A.; Pimentel, J.L.; Pureur, P.; Landinez Tellez, D.A.; Roa-Rojas, J.

    2009-01-01

    In this work we report the analysis of magnetization experimental data of the La 0.5 RE 0.5 BaCaCu 3 O 7-δ (RE=Y, Sm, Gd, Dy, Ho, Yb) superconducting system. The data are analyzed in terms of thermal fluctuations on the magnetization excess ΔM(T) for different values of temperature in each one of the samples. We describe a procedure for extracting the penetration depth λ ab (∼1571A) and the coherence length ξ ab (∼1.52A) parameters from the magnetization, as a function of the applied magnetic field. This procedure was performed for polycrystalline samples of La 0.5 RE 0.5 BaCaCu 3 O 7-δ by using the theory of Bulaevskii, Ledvij and Kogan, which analyzes the vortex fluctuation in superconducting materials within the Lawrence-Doniach framework. These data allowed to determine the characteristic temperature value T * (73, 58, 48, 57, 56, 71 K, for RE=Y, Sm, Gd, Dy, Ho, Yb, respectively) in the magnetization curves for several magnetic fields. We calculated the data of magnetization excess from the curves of magnetization as a function of logarithm of applied field. We notice that the values for these superconducting parameters are in agreement with the reports for high temperature superconductors. The obtained value of superconducting volumetric fraction is compared with that obtained through the measure of the Meissner effect.

  19. Anisotropic magnetization and transport properties of RAgSb2 (R=Y, La-Nd, Sm, Gd-Tm)

    Energy Technology Data Exchange (ETDEWEB)

    Myers, Kenneth D. [Iowa State Univ., Ames, IA (United States)

    1999-11-08

    This study of the RAgSb2 series of compounds arose as part of an investigation of rare earth intermetallic compounds containing antimony with the rare earth in a position with tetragonal point symmetry. Materials with the rare earth in a position with tetragonal point symmetry frequently manifest strong anisotropies and rich complexity in the magnetic properties, and yet are simple enough to analyze. Antimony containing intermetallic compounds commonly possess low carrier densities and have only recently been the subject of study. Large single grain crystals were grown of the RAgSb2 (R=Y, La-Nd, Sm, Gd-Tm) series of compounds out of a high temperature solution. This method of crystal growth, commonly known as flux growth is a versatile method which takes advantage of the decreasing solubility of the target compound with decreasing temperature. Overall, the results of the crystal growth were impressive with the synthesis of single crystals of LaAgSb2 approaching one gram. However, the sample yield diminishes as the rare earth elements become smaller and heavier. Consequently, no crystals could be grown with R=Yb or Lu. Furthermore, EuAgSb2 could not be synthesized, likely due to the divalency of the Eu ion. For most of the RAgSb2 compounds, strong magnetic anisotropies are created by the crystal electric field splitting of the Hund's rule ground state. This splitting confines the local moments to lie in the basal plane (easy plane) for the majority of the members of the series. Exceptions to this include ErAgSb2 and TmAgSb2, which have moments along the c-axis (easy axis) and CeAgSb2, which at intermediate temperatures has an easy plane, but exchange coupling at low temperatures is anisotropic with an easy axis. Additional anisotropy is also observed within the basal plane of DyAgSb2, where the moments are restricted to align along one of the <110> axes. Most of

  20. Re-dispersion and film formation of GdVO4 :  Ln3+ (Ln3+ = Dy3+, Eu3+, Sm3+, Tm3+) nanoparticles: particle size and luminescence studies.

    Science.gov (United States)

    Shanta Singh, N; Ningthoujam, R S; Phaomei, Ganngam; Singh, S Dorendrajit; Vinu, A; Vatsa, R K

    2012-04-21

    GdVO(4) : Ln(3+) (Ln(3+) = Dy(3+), Eu(3+), Sm(3+), Tm(3+)) nanoparticles are prepared by a simple chemical route at 140 °C. The crystallite size can be tuned by varying the pH of the reaction medium. Interestingly, the crystallite size is found to increase significantly when pH increases from 6 to 12. This is related to slower nucleation of the GdVO(4) formation with increase of VO(4)(3-) present in solution. The luminescence study shows an efficient energy transfer from vanadate absorption of GdVO(4) to Ln(3+) and thereby enhanced emissions are obtained. A possible reaction mechanism at different pH values is suggested in this study. As-prepared samples are well dispersed in ethanol, methanol and water, and can be incorporated into polymer films. Luminescence and its decay lifetime studies confirm the decrease in non-radiative transition probability with the increase of heat treatment temperature. Re-dispersed particles will be useful in potential applications of life science and the film will be useful in display devices.

  1. Oxide fluoride sulfides of the lanthanoids with the formula M{sub 6}O{sub 2}F{sub 8}S{sub 3} (M = La-Nd, Sm, Gd); Oxidfluoridsulfide der Lanthanoide vom Formeltyp M{sub 6}O{sub 2}F{sub 8}S{sub 3} (M = La-Nd, Sm, Gd)

    Energy Technology Data Exchange (ETDEWEB)

    Grossholz, Hagen; Zimmermann, Dirk D.; Janka, Oliver; Schleid, Thomas [Stuttgart Univ. (Germany). Inst. fuer Anorganische Chemie

    2013-07-15

    The lanthanoid(III) oxide fluoride sulfides M{sub 6}O{sub 2}F{sub 8}S{sub 3} (M = La-Nd, Sm, Gd) can be obtained by reacting the rare-earth metals, their trifluorides and sesquioxides with elemental sulfur in appropriate molar ratios at 850 C flux-assisted by NaCl in gas-tightly sealed niobium or tantalum ampoules. All compounds are colorless, except for those containing M = Pr with green, M = Nd with lilac and M = Sm with yellow color. They form transparent single crystals as needles or rods. The M{sub 6}O{sub 2}F{sub 8}S{sub 3} representatives crystallize in a hexagonal structure (space group: P6{sub 3}/m; a {approx} 1382-1326, c {approx} 398-376 pm, c/a {approx} 0.288-0.284; Z = 2) with two different crystallographic M{sup 3+} positions. The (M2){sup 3+} cations reside in ninefold coordination of anions arranged as tricapped trigonal prisms formed by three F{sup -}, four mixed-occupied O{sup 2-}/F{sup -} and two S{sup 2-} anions, resembling the unique M{sup 3+} coordination sphere of the M{sub 3}OF{sub 5}S-type oxide fluoride sulfides. The (M1){sup 3+} cations are surrounded by square antiprisms built of four O{sup 2-}/F{sup -} and S{sup 2-} anions each, which are capped by one F{sup -} anion each, again resulting in a ninefold coordination similar to that of the A-MFS-type fluoride sulfides. While the crystallographically unique S{sup 2-} anions have six cationic neighbors arranged in trigonal prisms, there are four different light-anion positions. Two of them, representing only fluoride anions, are situated in a triangular environment of cations ((F1){sup -}: planar, (F2){sup -}: non-planar). The mixed-occupied light-anion positions (F3){sup -}/(O3){sup 2-} and (F4){sup -}/(O4){sup 2-} exhibit tetrahedral coordination spheres with a ratio F{sup -}: O{sup 2-} = 2:1. The M{sub 6}O{sub 2}F{sub 8}S{sub 3} arrangement is characterized by an empty hexagonal channel structure created by (F1){sup -} anions with a potential of accommodating alkali-metal cations like Na

  2. Estimation of tau1 for the host Kramers' Ln3+ ions (Ln = Nd, Sm and Yb) from the EPR linewidths of Gd3+ impurity ions in Ln2(SO4)3.8H2O

    International Nuclear Information System (INIS)

    Malhotra, V.M.; Buckmaster, H.A.

    1981-01-01

    It is shown that the EPR linewidth data published by Misra and Mikolajczak for Gd 3+ impurity ions in Ln 2 (SO 4 ) 3 .8H 2 O (Ln = Nd, Sm and Yb) single crystals at 77 and 300 K can be used to estimate the effective spin-lattice relaxation time of Kramers' host ions. The various relaxation mechanisms which are operative in the lanthanides are reviewed and discussed. The estimated relaxation times are shown to be a sensitive function of the host ion energy level splittings and the temperature. The estimated effective spin-lattice relaxation times in these hosts are in reasonable agreement with those expected from a resonance Orbach process

  3. K2Ln2As2Se9 (Ln = Sm, Gd): the first quaternary rare-earth selenoarsenate compounds with a 3D framework containing chairlike As2Se4 units.

    Science.gov (United States)

    Wu, Yuandong; Bensch, Wolfgang

    2009-04-06

    The new compounds K(2)Ln(2)As(2)Se(9) (Ln = Sm, Gd) were obtained by applying the reactive flux method. The structure consists of a three-dimensional (3D) [Ln(2)As(2)Se(9)](2-) framework with K(+) ion-filling tunnels running along the b axis. The two unique Ln(3+) cations are coordinated by two Se(2)(2-) dumbbells, two AsSe(3)(3-) pyramids, and one chairlike As(2)Se(4)(2-) unit in a bicapped trigonal-prismatic geometry. The Ln(3+)-centered trigonal prisms share triangular faces with neighboring prisms, forming one-dimensional chains along the b axis. These chains are linked to each other to form layers by sharing Se(2-) anions on the capped sites of the trigonal prisms. The As(2)Se(4) units connect these layers to form the 3D framework.

  4. Synthesis and characterization of heterobinuclear (La-Zn, Pr-Zn, Nd-Zn, Sm-Zn, Eu-Zn, Gd-Zn, Tb-Zn, Dy-Zn) azine-bridged complexes

    International Nuclear Information System (INIS)

    Singh, Bachcha; Srivastav, A.K.; Singh, P.K.

    1997-01-01

    Zinc(II) complex of 2-acetylpyridine salicyl aldazine (Haps) of the type Zn(aps) 2 (H 2 O) 2 has been synthesised. The reaction of Zn(aps) 2 (H 2 O) 2 with lanthanide chlorides, LnCl 3 (where Ln=La, Pr, Nd, Sm, Eu, Gd, Tb and Dy) yields azine-bridged heterobinuclear complexes of the formulae LnCl 3 Zn(aps) 2 (H 2 O) 2 . These complexes have been characterized by elemental analyses, molecular weight, conductance (solid and solution) and magnetic susceptibility measurements, mass, IR and electronic spectral data. X-ray powder diffraction data indicate the tetragonal unit lattice for Zn(aps) 2 (H 2 O) 2 and PrCl 3 Zn(aps) 2 (H 2 O) 2 . (author)

  5. Stabilization of the ferromagnetic metallic state in rare earth-doped La0.49X0.01Ca0.50MnO3+δ (X=Nd, Sm, Gd and Yb)

    International Nuclear Information System (INIS)

    Aslam, Affia; Hasanain, S.K.; Akhtar, M.J.; Nadeem, M.

    2006-01-01

    We report the effects of disorder induced by a small amount of substitution of the smaller cations (Nd, Sm, Gd and Yb) for La in the La 0.50 Ca 0.50 MnO 3+δ system. With decreasing size of the dopant, the ferromagnetic and metallic state is stabilized while the AFM and insulating behaviour is completely eliminating. The magnetic moment below T c increases in general, with decreasing dopant size. The behaviour is interpreted in terms of the destabilization of the charge ordering (CO) due to the disorder induced by the size mismatch of the cations. Our data support the view that close to the COI-FM phase boundary, the effect of disorder is to weaken the CO that is more sensitive to disorder, whereas it leaves the more robust double exchange relatively unaffected, thereby extending the region in phase space where the FM phase is stable

  6. Synthesis and characterization of La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III) and Dy(III) complexes of 2-acetylfuran-2-thenoylhydrazone

    International Nuclear Information System (INIS)

    Singh, B.; Singh, Praveen K.

    1998-01-01

    The reaction of 2-acetylfuran-2-thenoylhydrazone(afth) with Ln(III) trichlorides yields complexes of the type [Ln(afth)Cl 2 (H 2 O)(EtOH)]Cl, [Ln(III) = La, Pr, Nd, Sm, Eu, Gd, Tb and Dy]. The complexes have been characterized by molar conductance, magnetic susceptibility and TGA and DTA measurements, magnetic susceptibility and TGA and DTA measurements, FAB mass, infrared, proton NMR, electronic absorption and emission spectra. The terbium complex is found to be monomer from the FAB mass spectrum. The IR and NMR spectra suggest neutral tridentate behaviour of the Schiff base. A coordination number seven is proposed around the metal ions. Emission spectra suggest C 3v , symmetry around the metal ion with capped octahedron geometry for the europium complex. (author)

  7. Distribution behavior of uranium, neptunium, rare-earth elements (Y, La, Ce, Nd, Sm, Eu, Gd) and alkaline-earth metals (Sr,Ba) between molten LiCl-KCl eutectic salt and liquid cadmium or bismuth

    International Nuclear Information System (INIS)

    Kurata, M.; Sakamura, Y.; Hijikata, T.; Kinoshita, K.

    1995-01-01

    Distribution coefficients of uranium neptunium, eight rare-earth elements (Y, La, Ce, Pr, Nd, Sm, Eu and Gd) and two alkaline-earth metals (Sr and Ba) between molten LiCl-KCl eutectic salt and either liquid cadmium or bismuth were measured at 773 K. Separation factors of trivalent rare-earth elements to uranium or neptunium in the LiCl-KCl/Bi system were by one or two orders of magnitude larger than those in the LiCl-KCl/Cd system. On the contrary, the separation factors of alkaline-earth metals and divalent rare-earth elements to trivalent rare-earth elements were by one or two orders of magnitude smaller in the LiCl-KCl/Bi system. (orig.)

  8. Mid-temperature deep removal of hydrogen sulfide on rare earth (RE = Ce, La, Sm, Gd) doped ZnO supported on KIT-6: Effect of RE dopants and interaction between active phase and support matrix

    Science.gov (United States)

    Li, Lu; Zhou, Pin; Zhang, Hongbo; Meng, Xianglong; Li, Juexiu; Sun, Tonghua

    2017-06-01

    Rare earth oxides (RE = Ce, La, Sm and Gd) doped ZnO supported on KIT-6 sorbents (RE-ZnO/KIT-6) were synthesized by sol-gel method and their performance for deep removal of H2S (bellow 0.1 ppmv) from gas stream at medium temperature was tested. The RE dopants (except Ce) significantly enhance the deep desulfurization capacity of ZnO/KIT-6 sorbent and maintained higher sulfur uptake capacities upon multiple cycles of regeneration by a simple thermal oxidation in 10 v% of O2 in N2 atmosphere. The results of SAXS, XRD, N2 physisorption, TEM, FIIR, and XPS implied that the KIT-6 structure of loading metal oxides remained intact. It was found that RE could hinder the ZnO crystal ripening during calcination resulted in smaller ZnO particles, enhance the interaction of ZnO and silica matrix to improve the dispersion of active phase on KIT-6. Furthermore, by increasing the outlayer electron density of Zn atom and oxygen transfer ability, the synergistic effect considered to be favorable for RE-ZnO/KIT-6 sulfidation. Even though the performance of improving ZnO dispersion was weaker than that of Sm and Gd, La-ZnO/KIT-6 performs the best deep desulfurizers by changing the surface chemical atmosphere for ZnO. Steam in the gas stream inhibited the capture of H2S by ZnO in the sorbents, in the case of La-ZnO/KIT-6, the steam content should control as lower as 5 v% to ensure the desulfurization efficiency and precision.

  9. High-pressure synthesis and magnetic behavior of A-site columnar-ordered double perovskites, LnMn(Ga{sub 0.5}Ti{sub 0.5}){sub 2}O{sub 6} (Ln = Sm, Gd)

    Energy Technology Data Exchange (ETDEWEB)

    Shimura, Gen; Niwa, Ken; Shirako, Yuichi; Hasegawa, Masashi [Department of Crystalline Materials Science, Nagoya University, 464-8601, Nagoya (Japan)

    2017-01-26

    A-site columnar-ordered double perovskites, LnMn(Ga{sub 0.5}Ti{sub 0.5}){sub 2}O{sub 6} (Ln = Sm, Gd), were successfully synthesized under high pressure and high temperature (6 GPa, 1375 K). From the synchrotron powder X-ray diffraction patterns, all of the diffraction peaks can be indexed by the P4{sub 2}/nmc space group with lattice parameters a, c ∼ 2a{sub p} (a{sub p}: primitive cubic perovskite lattice) and no ordering of the B-site cations. Rietveld analysis of the synchrotron powder X-ray diffraction patterns and Curie-Weiss fitting of their magnetizations reveal that the ionic formulae of these perovskites are Ln{sup 3+}Mn{sup 2+}(Ga{sup 3+}{sub 0.5}Ti{sup 4+}{sub 0.5}){sub 2}O{sup 2-}{sub 6}. SmMn(Ga{sub 0.5}Ti{sub 0.5}){sub 2}O{sub 6} shows canted-antiferromagnetic behavior, whereas GdMn(Ga{sub 0.5}Ti{sub 0.5}){sub 2}O{sub 6} exhibits two different magnetic states at low temperature depending on the applied magnetic field and shows an unusual magnetization curve. These magnetic behaviors originate by decreasing the antiferromagnetic interaction by substituting Ga{sup 3+}(d{sup 10}) for Ti{sup 4+}(d{sup 0}) and by decreasing the ferromagnetic interaction between columnar-ordered Ln{sup 3+} and Mn{sup 2+}. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Effects of rare-earth substitution on the stability and electronic structure of REZnOSb (RE = La-Nd, Sm-Gd) investigated via first-principles calculations

    International Nuclear Information System (INIS)

    Guo Kai; Man Zhenyong; Cao Qigao; Chen Haohong; Guo Xiangxin; Zhao Jingtai

    2011-01-01

    Graphical abstract: The structure stability of REZnOSb decreases with varying rare-earth from La to Gd because of the increased binding energy. Research highlights: → As increasing the atomic number of the RE, the structural stability of REZnOSb decreases. → Varying the rare-earth elements from La to Gd, the covalent interactions between [ZnSb] and [LaO] layer are enhanced by 4f-electrons. → The electrical transport properties of REZnOSb could be improved using the large atomic number of the RE. - Abstract: The structural stability, chemical bonding, Mulliken populations, and charge-density distribution of REZnOSb (RE = La-Nd, Sm-Gd) were investigated by first-principles calculations. Unit cell parameters calculated by the generalized gradient approximation (GGA) are in better agreement with experimental results than those derived from the local density approximation (LDA). Binding energy comparisons indicate that the structural stability of REZnOSb decreases with the increment of the atomic number of the RE, as confirmed by X-ray diffraction (XRD) results. Semimetal or narrow band-gap semiconductor behaviors are found for selected REZnOSb. Moreover, chemical bonding analysis shows that there exist considerable polar covalent interactions between the participating atoms. It also reveals that the [ZnSb] layers receive some electrons from the [LaO] layers (donor) as an electrons acceptor and holes transport tunnel. The covalent interactions between the [ZnSb] and [LaO] layers, which are enhanced by 4f-electrons of the RE, are supposed to improve the electrical transport properties.

  11. Mid-temperature deep removal of hydrogen sulfide on rare earth (RE = Ce, La, Sm, Gd) doped ZnO supported on KIT-6: Effect of RE dopants and interaction between active phase and support matrix

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lu; Zhou, Pin; Zhang, Hongbo; Meng, Xianglong; Li, Juexiu; Sun, Tonghua, E-mail: sunth@sjtu.edu.cn

    2017-06-15

    Highlights: • Various rare earth (RE)-doped ZnO/KIT-6 sorbents were prepared via sol-gel method. • La showed the highest efficiency on promoting ZnO/KIT-6 desulfurization activity. • The morphology of ZnO on KIT-6 played a crucial role for the reactivity. • The most initial factor of improving reactivity by RE was surface chemical property. • Crystallinity, host-guest interaction were also important to ZnO state on support. - Abstract: Rare earth oxides (RE = Ce, La, Sm and Gd) doped ZnO supported on KIT-6 sorbents (RE-ZnO/KIT-6) were synthesized by sol-gel method and their performance for deep removal of H{sub 2}S (bellow 0.1 ppmv) from gas stream at medium temperature was tested. The RE dopants (except Ce) significantly enhance the deep desulfurization capacity of ZnO/KIT-6 sorbent and maintained higher sulfur uptake capacities upon multiple cycles of regeneration by a simple thermal oxidation in 10 v% of O{sub 2} in N{sub 2} atmosphere. The results of SAXS, XRD, N{sub 2} physisorption, TEM, FIIR, and XPS implied that the KIT-6 structure of loading metal oxides remained intact. It was found that RE could hinder the ZnO crystal ripening during calcination resulted in smaller ZnO particles, enhance the interaction of ZnO and silica matrix to improve the dispersion of active phase on KIT-6. Furthermore, by increasing the outlayer electron density of Zn atom and oxygen transfer ability, the synergistic effect considered to be favorable for RE-ZnO/KIT-6 sulfidation. Even though the performance of improving ZnO dispersion was weaker than that of Sm and Gd, La-ZnO/KIT-6 performs the best deep desulfurizers by changing the surface chemical atmosphere for ZnO. Steam in the gas stream inhibited the capture of H{sub 2}S by ZnO in the sorbents, in the case of La-ZnO/KIT-6, the steam content should control as lower as 5 v% to ensure the desulfurization efficiency and precision.

  12. Mid-temperature deep removal of hydrogen sulfide on rare earth (RE = Ce, La, Sm, Gd) doped ZnO supported on KIT-6: Effect of RE dopants and interaction between active phase and support matrix

    International Nuclear Information System (INIS)

    Li, Lu; Zhou, Pin; Zhang, Hongbo; Meng, Xianglong; Li, Juexiu; Sun, Tonghua

    2017-01-01

    Highlights: • Various rare earth (RE)-doped ZnO/KIT-6 sorbents were prepared via sol-gel method. • La showed the highest efficiency on promoting ZnO/KIT-6 desulfurization activity. • The morphology of ZnO on KIT-6 played a crucial role for the reactivity. • The most initial factor of improving reactivity by RE was surface chemical property. • Crystallinity, host-guest interaction were also important to ZnO state on support. - Abstract: Rare earth oxides (RE = Ce, La, Sm and Gd) doped ZnO supported on KIT-6 sorbents (RE-ZnO/KIT-6) were synthesized by sol-gel method and their performance for deep removal of H 2 S (bellow 0.1 ppmv) from gas stream at medium temperature was tested. The RE dopants (except Ce) significantly enhance the deep desulfurization capacity of ZnO/KIT-6 sorbent and maintained higher sulfur uptake capacities upon multiple cycles of regeneration by a simple thermal oxidation in 10 v% of O 2 in N 2 atmosphere. The results of SAXS, XRD, N 2 physisorption, TEM, FIIR, and XPS implied that the KIT-6 structure of loading metal oxides remained intact. It was found that RE could hinder the ZnO crystal ripening during calcination resulted in smaller ZnO particles, enhance the interaction of ZnO and silica matrix to improve the dispersion of active phase on KIT-6. Furthermore, by increasing the outlayer electron density of Zn atom and oxygen transfer ability, the synergistic effect considered to be favorable for RE-ZnO/KIT-6 sulfidation. Even though the performance of improving ZnO dispersion was weaker than that of Sm and Gd, La-ZnO/KIT-6 performs the best deep desulfurizers by changing the surface chemical atmosphere for ZnO. Steam in the gas stream inhibited the capture of H 2 S by ZnO in the sorbents, in the case of La-ZnO/KIT-6, the steam content should control as lower as 5 v% to ensure the desulfurization efficiency and precision.

  13. Power-law index and penetration depth of (NdxSmxGd1−2x)Ba2Cu3O7−δ films studied by AC susceptibility

    DEFF Research Database (Denmark)

    Li, Xiaofen; He, Dong; Grivel, Jean-Claude

    2012-01-01

    Superconducting (NdxSmxGd1−2x)Ba2Cu3O7−δ films with x=0, 0.1, 0.25, 0.33 were grown by PLD on STO single crystal substrates. The power-law index n and penetration depth λ are studied by AC susceptibility. During cooling, n in films with x ≠ 0 increases much slower compared with the films with x =....... The films with x ≠ 0 also tend to have a longer penetration depth. These properties might be related to the higher possibility for disorder in the mixed (Nd,Sm,Gd)BCO films....

  14. RE{sub 3}Ga{sub 9}Ge (RE=Y, Ce, Sm, Gd and Yb): compounds with an open three-dimensional polygallide framework synthesized from liquid gallium

    Energy Technology Data Exchange (ETDEWEB)

    Zhuravleva, M A; Kanatzidis, M G

    2003-07-01

    The RE{sub 3}Ga{sub 9}Ge compounds (RE=Y, Ce, Sm, Gd and Yb) were synthesized at 850 deg. C in quantitative yield from reactions containing excess liquid Ga. The orthorhombic crystal structure is characterized by a unique three-dimensional open Ga framework with parallel straight tunnels. In the tunnels, inserted are arrays of the RE atoms together with interpenetrated monoatomic RE-Ga-Ge planes. A complex disordered arrangement of the RE and Ga atoms is observed in the monoatomic plane. Depending on the extent of disorder, the crystal structure could be presented either in a sub-cell (no ordering) or in a super-cell (partial ordering). Single-crystal X-ray data for Ce{sub 3}Ga{sub 9}Ge sub-structure: space group Immm, Z=2, cell parameters a=4.3400(12) A; b=10.836(3) A; and c=11.545(3) A; super-structure: space group Cmma, Z=8, cell parameters a=8.680(3) A; b=23.090(7) A; and c=10.836(3) A. The refinement based on the full-matrix least squares on F{sub o}{sup 2}[I>2{sigma}(I)] converged to final residuals R{sub 1}/wR{sub 2}=0.0226/0.0528 and 0.0729/0.1569 for the sub- and super-structures, respectively. The relationship between the disordered sub-structure and partially ordered super-structure is discussed. Magnetic susceptibility measurements show Curie-Weiss behavior at the temperatures above 30 K with the negative Weiss constants {theta}=-49(1) and-7.7 K for Gd and Ce analogs, respectively. An antiferromagnetic transition is observed in the Gd analog at T{sub N}=26.1 K. The {mu}{sub eff} obtained for both analogs is close to the RE{sup 3+} free-ion value.

  15. Structure and Chemical Bonding of the Li-Doped Polar Intermetallic RE2In1−xLixGe2 (RE = La, Nd, Sm, Gd; x = 0.13, 0.28, 0.43, 0.53 System

    Directory of Open Access Journals (Sweden)

    Junsu Lee

    2018-03-01

    Full Text Available Four polar intermetallic compounds belonging to the RE2In1−xLixGe2 (RE = La, Nd, Sm, Gd; x = 0.13(1, 0.28(1, 0.43(1, 0.53(1 system have been synthesized by the traditional solid-state reaction method, and their crystal structures have been characterized by single-crystal X-ray diffraction (SXRD analyses. The isotypic crystal structures of four title compounds adopt the Mo2FeB2-type structure having the tetragonal space group P4/mbm (Z = 2, Pearson code tP40 with three crystallographically independent atomic sites and can be simply described as a pile of the identical 2-dimensioanl (2D RE2In1-xLixGe2 slabs stacked along the c-axis direction. The substituting Li atom shows a particular site preference for replacing In at the Wyckoff 2a site rather than Ge at the Wyckoff 4g in this crystal structure. As the size of a used rare-earth metal decreases from La3+ to Gd3+ throughout the title system, the Ge-Ge and Ge-In/Li bond distances, both of which consist of the 2D anionic Ge2(In/Li layer, gradually decrease resulting in the reduction of a unit cell volume. A series of theoretical investigations has been performed using a hypothetical structure model Gd2In0.5Li0.5Ge2 by tight-binding linear muffin-tin orbital (TB-LMTO method. The resultant densities of states (DOS value at the Fermi level (EF suggests a metallic conductivity for this particular composition, and this calculation result is in a good agreement with the formal charge distribution assigning two extra valence electrons for a metal-metal bond in the conduction band. The thorough analyses of six crystal orbital Hamilton population (COHP curves representing various interatomic interactions and an electron localization function (ELF diagram indicating the locations of paired-electron densities are also provided in this article.

  16. Mass of the 158Sm

    International Nuclear Information System (INIS)

    Zhao Kui; Guo Jiyu; Lu Xiuqin; Cheng Yehao; Huang Xiaolin; Ma Yong; Li Shuyuan; Ruan Ming; Li Zhichang; Jiang Chenglie

    1997-01-01

    A preliminary result was reported for the experiment to determine the mass of the heavier neutron-rich nucleus 158 Sm using the 160 Gd( 18 O, 20 Ne) two proton transfer reaction in last progress report. The average Q-value of (4.046 +- 0.102) MeV for the 160 Gd( 18 O, 20 Ne) 158 Sm reaction is given. A mass excess for 158 Sm of (-65.738 +- 0.102) MeV was derived. This is the first experimentally measured value of the mass of 158 Sm which is about 450 keV higher than the evaluation value from systematic trends listed in the 1993 atomic mass table. The new prediction shows better agreement with the measured values and a significant improvement over the earlier FRDM (finite-range droplet model) value

  17. In pursuit of the rhabdophane crystal structure: from the hydrated monoclinic LnPO{sub 4}.0.667H{sub 2}O to the hexagonal LnPO{sub 4} (Ln = Nd, Sm, Gd, Eu and Dy)

    Energy Technology Data Exchange (ETDEWEB)

    Mesbah, Adel, E-mail: adel.mesbah@cea.fr [ICSM, UMR 5257 CNRS – CEA – ENSCM – Université de Montpellier, Site de Marcoule - Bât 426, BP 17171, 30207 Bagnols/Cèze (France); Clavier, Nicolas [ICSM, UMR 5257 CNRS – CEA – ENSCM – Université de Montpellier, Site de Marcoule - Bât 426, BP 17171, 30207 Bagnols/Cèze (France); Elkaim, Erik [Synchrotron SOLEIL, L' Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex (France); Szenknect, Stéphanie; Dacheux, Nicolas [ICSM, UMR 5257 CNRS – CEA – ENSCM – Université de Montpellier, Site de Marcoule - Bât 426, BP 17171, 30207 Bagnols/Cèze (France)

    2017-05-15

    The dehydration process of the hydrated rhabdophane LnPO{sub 4}.0.667H{sub 2}O (Ln = La to Dy) was thoroughly studied over the combination of in situ high resolution synchrotron powder diffraction and TGA experiments. In the case of SmPO{sub 4}.0.667H{sub 2}O (monoclinic, C2), a first dehydration step was identified around 80 °C leading to the formation of SmPO{sub 4}.0.5H{sub 2}O (Monoclinic, C2) with Z =12 and a =17.6264(1) Å, b =6.9704(1) Å, c =12.1141(1) Å, β=133.74(1) °, V =1075.33(1) Å{sup 3}. In agreement with the TGA and dilatometry experiments, all the water molecules were evacuated above 220 °C yielding to the anhydrous form, which crystallizes in the hexagonal P3{sub 1}21 space group with a =7.0389(1) Å, c =6.3702(1) Å and V =273.34(1) Å{sup 3}. This study was extended to selected LnPO{sub 4}.0.667H{sub 2}O samples (Ln= Nd, Gd, Eu, Dy) and the obtained results confirmed the existence of two dehydration steps before the stabilization of the anhydrous form, with the transitory formation of LnPO{sub 4}.0.5H{sub 2}O. - Graphical abstract: The dehydration process of the rhabdophane SmPO{sub 4}.0.667H{sub 2}O was studied over combination of in situ high resolution synchrotron powder diffraction and TGA techniques, a first dehydration was identified around 80 °C leading to the formation of SmPO{sub 4}.0.5H{sub 2}O (Monoclinic, C2). Then above 220 °C, the anhydrous form of the rhabdophane SmPO{sub 4} was stabilized and crystallizes in the hexagonal P3{sub 1}21 space group. - Highlights: • In situ synchrotron powder diffraction was carried out during the dehydration of the rhabdopahe LnPO{sub 4}.0.667H{sub 2}O. • The heat of the rhabdophane LnPO{sub 4}.0.667H{sub 2}O leads to LnPO{sub 4}.0.5H{sub 2}O then to anhydrous rhabdophane LnPO{sub 4}. • LnPO{sub 4}.0.5H{sub 2}O (monoclinic, C2) and LnPO{sub 4} (Hexagonal, P3{sub 1}21) were solved over the use of direct methods.

  18. RE{sub 3}Au{sub 5}Zn (RE = Y, Sm, Gd-Ho). A new structure type with five- and six-membered rings as building units in a gold network

    Energy Technology Data Exchange (ETDEWEB)

    Gerke, Birgit; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie and NRW Graduate School of Chemistry

    2016-08-01

    RE{sub 3}Au{sub 5}Zn (RE = Y, Sm, Gd-Ho) intermetallic compounds were synthesized by melting the elements in sealed tantalum tubes. They exhibit a new structure type which was studied by X-ray diffraction on powders and refined from single crystal diffraction data: Cmcm, a = 736.9(2), b = 1489.4(2), c = 1330.4(3) pm, wR2 = 0.0371, 1184 F{sup 2} values and 55 variables for Y{sub 3}Au{sub 4.92}Zn{sub 1.08} and a = 739.0(1), b = 1495.8(2), c = 1339.2(2) pm, wR2 = 0.0325, 1410 F{sup 2} values and 54 variables for Tb{sub 3}Au{sub 5}Zn. The network consists of five- and six-membered gold rings in puckered conformations. Atoms of the rare earth elements are placed within the cavities of this network where every third cavity is filled by a Zn{sub 2} dumbbell. The structure is discussed in detail and compared with the gold substructure of Hf{sub 7}Au{sub 10}.

  19. Cu k-edge studies of the charge carries in Th-doped cuprate system R2-xThxCuO4-δ (R = Nd, Sm and Gd)

    International Nuclear Information System (INIS)

    Liang, G.; Yi, Y.; Jardim, R.F.; Wang, L.V.

    1999-01-01

    To further study the charge carrier concentration in electron doped cuprate superconductors, a systematic x-ray absorption near edge structure (XANES) measurement has been carried out on Th-doped superconductor system R 2-x Th x CuO 4-δ (R = Nd, Sm, and Gd). The XANES results show that, similar to the Ce-doped compounds, while the intensity of the Cu 1+ 4p π feature increase with the increase of the Th doping level x, the intensities of the Cu 2+ 4p π and 4p σ features decreases. This clearly indicates that the electrons doped by the Th atoms are injected into the local Cu 3d-orbitals. The normalized Cu 1+ 4p π intensity data show that the Cu 1+ concentration in the Th-doped compound series with different R-elements is linearly proportional to the Th doping-level x. The data suggest that both Ce and Th donate the same fraction of electrons into the Cu sites

  20. 1,3-thiazole as suitable antenna ligand for lanthanide photoluminescence in [LnCl{sub 3}(thz){sub 4}].0.5thz, Ln = Sm, Eu, Gd, Tb, Dy

    Energy Technology Data Exchange (ETDEWEB)

    Dannenbauer, Nicole; Mueller-Buschbaum, Klaus [Wuerzburg Univ. (Germany). Inst. for Inorganic Chemistry; Kuzmanoski, Ana; Feldmann, Claus [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany). Inst. for Inorganic Chemistry

    2014-02-15

    The series of luminescent monomeric lanthanide thiazole complexes [LnCl{sub 3}(thz){sub 4}].0.5thz (Ln = Sm, Eu, Gd, Tb, Dy; thz = 1,3-thiazole) has been synthesised and characterised by powder and single-crystal X-ray diffraction, IR and photoluminescence spectroscopy, DTA/TG as well as elemental analysis. The colourless compounds exhibit photoluminescence in the visible region with varying quantum efficiencies up to QY = 48 % for [LnCl{sub 3}(thz){sub 4}].0.5thz. Both, the lanthanide ions as well as the thiazole ligand contribute to the luminescence. Excitation can be achieved via intra-4f transitions and by exciting the ligand, emission is observed mainly from the lanthanide ions again by 4f transitions. Thiazole can transfer energy to the lanthanide ions, which further feeds the lanthanide emission by an efficient antenna effect even at room temperature. The lanthanide ions show pentagonal-bipyramidal coordination by three chloride anions and four N atoms of 1,3-thiazole, which leads to a strong {sup 5}D{sub 0} → {sup 7}F{sub 4} transition for europium. Significant differences arise as compared to thiophene complexes because no sulphur atom is involved in the metal coordination, as the thiazole ligand is solely coordinated via its nitrogen function. (orig.)

  1. Effects of annealing on the microstructure, corrosion resistance, and mechanical properties of RE{sub 65}Co{sub 25}Al{sub 10} (RE=Ce, La, Pr, Sm, and Gd) bulk metallic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Zhou [School of Materials Science and Engineering, University of Jinan, No. 336, West Road of Nan Xinzhuang, Jinan 250022 (China); Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, No. 336, West Road of Nan Xinzhuang, Jinan 250022 (China); Xing, Qi; Sun, Zhenxi; Xu, Jing; Zhao, Zhengfeng [School of Materials Science and Engineering, University of Jinan, No. 336, West Road of Nan Xinzhuang, Jinan 250022 (China); Chen, Shuying; Liaw, Peter K. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN (United States); Wang, Yan, E-mail: mse_wangy@ujn.edu.cn [School of Materials Science and Engineering, University of Jinan, No. 336, West Road of Nan Xinzhuang, Jinan 250022 (China); Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, No. 336, West Road of Nan Xinzhuang, Jinan 250022 (China)

    2015-02-25

    The effects of annealing on the microstructure, corrosion resistance and mechanical properties of the RE{sub 65}Co{sub 25}Al{sub 10} (RE=Ce, La, Pr, Sm, and Gd) bulk metallic glasses (BMGs) were studied. Microstructural changes are induced after annealing below the onset crystallization temperature of 484 K, resulting in the variation of thermal stability and crystallization behavior. A proper annealing enhances the corrosion resistance in 3.5 wt% NaCl solution, which can be attributed to reduction of the electrochemical activity and galvanic coupling effects in the chloride solution. Moreover, the RE-based BMG annealed at 484 K possesses the higher corrosion potential and lower corrosion current density, combined with the corrosion morphologies, which suggests the best corrosion resistance. Annealing can also obviously change the mechanical properties and fracture morphologies. It presents that free volume annihilation can cause more difficulty in the elastic atom rearrangement for the as-annealed RE-based BMGs.

  2. Effect of lanthanide on the microstructure and structure of LnMn0.5Fe0.5O3 nanoparticles with Ln=La, Pr, Nd, Sm and Gd prepared by the polymer precursor method

    International Nuclear Information System (INIS)

    Romero, Mariano; Faccio, Ricardo; Martínez, Javier; Pardo, Helena; Montenegro, Benjamín; Plá Cid, Cristiani Campos; Pasa, André A.

    2015-01-01

    The synthesis of LnMn 0.5 Fe 0.5 O 3 perovskite nanoparticles by the polymer precursor method showed a strong intrinsic dependence with different lanthanides (Ln=La, Pr, Nd, Sm and Gd). The polymerization level reached in the polymer precursor was proportional to the atomic number of lanthanide with exception of samarium, which showed the formation of a different precursor based in a citrate chelate with ethyleneglycol bonded as adduct. The increasing level of polymerization of the polymer precursors showed the formation of large-size perovskite nanoparticles after its calcination. SAXS and TEM analyses suggested that nanoparticles obtained, using this method, have a squared-like microstructure in connection with the polymer precursor microstructure. Structural analysis showed an orthorhombic structure with a slight decline in the Jahn–Teller distortion when the atomic number of lanthanide increases. Mössbauer spectroscopy showed the presence of a majority site in agreement with the Pbnm orthorhombic structure best fitted with Rietveld refinements and in some cases, a more distorted site attributed to local inhomogeneities and oxygen vacancies. - Highlights: • Precursor polymerization level is lower in the presence of lighter lanthanides. • Lighter lanthanide perovskite nanoparticles after calcination are lower-sized. • Nanoparticles obtained by this method have lamellae microstructure. • Jahn–Teller distortion declines for heavier lanthanide perovskites. • Oxygen vacancy phase was observed in lighter lanthanide perovskites

  3. Nitrato-complexes of Y(III), La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III) and Ho(III) with 2-(2'-pyridyl) benzimidazole

    International Nuclear Information System (INIS)

    Mishra, A.; Singh, M.P.; Singh, V.K.

    1982-01-01

    The nitrato-complexes, [Y(PyBzH) 2 (NO 3 ) 2 ]NO 3 .H 2 O and Nd, Sm, Gd, Tb, Dy, Ho ; n=1-3, m=0-0.5 ; PyBzh=2-(2 -pyridyl)benzimidazole] are formed on interaction of the ligand with metal nitrates in ethanol. The electrical conductance values (116-129 ohm -1 cm 2 mol -1 ) suggest 1:1 electrolyte-nature of the complexes. Magnetic moment values of Ce(2.53 B.M.), Pr(3.62 B.M.), Nd(3.52 B.M.), Sm(1.70 B.M.), Gd(8.06 B.M.), Tb(9.44 B.M.), Dy(10.56 B.M.) and Ho(10.51 B.M.) in the complexes confirm the terpositive state of the metals. Infrared evidences are obtained for the existance of both coordinated (C 2 v) and uncoordinated (D 3 h) nitrate groups. Electronic absorption spectra of Pr(III)-, Nd(III)-, Sm(III)-, Tb(III)-, Dy(III)- and Ho(III)-complexes have been analysed in the light of LSJ terms. (author)

  4. Nitrato-complexes of Y(III), La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III) and Ho(III) with 2-(2'-pyridyl) benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, A; Singh, M P; Singh, V K

    1982-05-01

    The nitrato-complexes, (Y(PyBzH)/sub 2/(NO/sub 3/)/sub 2/)NO/sub 3/.H/sub 2/O and Nd, Sm, Gd, Tb, Dy, Ho ; n=1-3, m=0-0.5 ; PyBzh=2-(2 -pyridyl)benzimidazole) are formed on interaction of the ligand with metal nitrates in ethanol. The electrical conductance values (116-129 ohm/sup -1/cm/sup 2/mol/sup -1/) suggest 1:1 electrolyte-nature of the complexes. Magnetic moment values of Ce(2.53 B.M.), Pr(3.62 B.M.), Nd(3.52 B.M.), Sm(1.70 B.M.), Gd(8.06 B.M.), Tb(9.44 B.M.), Dy(10.56 B.M.) and Ho(10.51 B.M.) in the complexes confirm the positive state of the metals. Infrared evidences are obtained for the existance of both coordinated (C/sub 2/v) and uncoordinated (D/sub 3/h) nitrate groups. Electronic absorption spectra of Pr(III)-, Nd(III)-, Sm(III)-, Tb(III)-, Dy(III)- and Ho(III)-complexes have been analysed in the light of LSJ terms.

  5. Investigation of the transport properties and compositions of the Ca{sub 2}RE{sub 7}Pn{sub 5}O{sub 5} series (RE=Pr, Sm, Gd, Dy; Pn=Sb, Bi)

    Energy Technology Data Exchange (ETDEWEB)

    Forbes, Scott [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1 (Canada); Yuan, Fang [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1 (Canada); Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Kosuda, Kosuke; Kolodiazhnyi, Taras [Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Mozharivskyj, Yurij, E-mail: mozhar@mcmaster.ca [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1 (Canada)

    2016-10-15

    The Ca{sub 2}RE{sub 7}Pn{sub 5}O{sub 5} phases (RE=Pr, Sm, Gd, Dy; Pn=Sb, Bi) were successfully prepared from high temperature reactions at 1225–1300 °C. These phases maintain the same structure types as the parent RE{sub 9}Pn{sub 5}O{sub 5} phases, except for a Ca/RE mixing. The study and preparation of these phases was motivated by the desire to shift the metallic type properties of the parent RE{sub 9}Pn{sub 5}O{sub 5} phases to a level more suitable for thermoelectric applications. Electrical resistivity measurements performed on pure, bulk samples indicated all phases to be narrow band gap semiconductors or semimetals, supporting the charge balanced electron count of the Ca{sub 2}RE{sub 7}Pn{sub 5}O{sub 5} composition. Unfortunately, all samples are too electrically resistive for any potential usage as thermoelectrics. Electronic band structure calculations performed on idealized RE{sub 9}Pn{sub 5}O{sub 5} structures revealed the presence of a pseudogap at the Fermi level, which is consistent with the observed electrical resistivity and Seebeck coefficient behavior. - Graphical abstract: Ca substitution in RE{sub 9}Pn{sub 5}O{sub 5} leads to charge-balanced Ca{sub 2}RE{sub 7}Pn{sub 5}O{sub 5} phases with semiconducting or semimetallic properties. - Highlights: • The RE{sub 9}Pn{sub 5}O{sub 5} structure may be stabilized with calcium substitution in the form of Ca{sub 2}RE{sub 7}Pn{sub 5}O{sub 5}. • The Ca{sub 2}RE{sub 7}Pn{sub 5}O{sub 5} phases maintain the parent P 4/n structure, albeit with Ca/RE mixing. • The Ca{sub 2}RE{sub 7}Sb{sub 5}O{sub 5} phases behave as semiconductors while Ca{sub 2}RE{sub 7}Bi{sub 5}O{sub 5} are semimetals with electron-electron correlations. • Electronic structure calculations yield a semimetal-like density of states for both Ca{sub 2}RE{sub 7}Sb{sub 5}O{sub 5} and Ca{sub 2}RE{sub 7}Bi{sub 5}O{sub 5}.

  6. Impact of electrically formed interfacial layer and improved memory characteristics of IrOx/high-κx/W structures containing AlOx, GdOx, HfOx, and TaOx switching materials.

    Science.gov (United States)

    Prakash, Amit; Maikap, Siddheswar; Banerjee, Writam; Jana, Debanjan; Lai, Chao-Sung

    2013-09-06

    Improved switching characteristics were obtained from high-κ oxides AlOx, GdOx, HfOx, and TaOx in IrOx/high-κx/W structures because of a layer that formed at the IrOx/high-κx interface under external positive bias. The surface roughness and morphology of the bottom electrode in these devices were observed by atomic force microscopy. Device size was investigated using high-resolution transmission electron microscopy. More than 100 repeatable consecutive switching cycles were observed for positive-formatted memory devices compared with that of the negative-formatted devices (only five unstable cycles) because it contained an electrically formed interfacial layer that controlled 'SET/RESET' current overshoot. This phenomenon was independent of the switching material in the device. The electrically formed oxygen-rich interfacial layer at the IrOx/high-κx interface improved switching in both via-hole and cross-point structures. The switching mechanism was attributed to filamentary conduction and oxygen ion migration. Using the positive-formatted design approach, cross-point memory in an IrOx/AlOx/W structure was fabricated. This cross-point memory exhibited forming-free, uniform switching for >1,000 consecutive dc cycles with a small voltage/current operation of ±2 V/200 μA and high yield of >95% switchable with a large resistance ratio of >100. These properties make this cross-point memory particularly promising for high-density applications. Furthermore, this memory device also showed multilevel capability with a switching current as low as 10 μA and a RESET current of 137 μA, good pulse read endurance of each level (>105 cycles), and data retention of >104 s at a low current compliance of 50 μA at 85°C. Our improvement of the switching characteristics of this resistive memory device will aid in the design of memory stacks for practical applications.

  7. Effect of mixing RE elements (Nd, Sm, Gd, Eu, Y, Yb) on the RE2BaCuO5/Nd4-2xBa2+2xCu2-xO10-2x phases in RE cuprate high-Tc superconductors

    International Nuclear Information System (INIS)

    Langhorn, J.B.; Black, M.A.; McGinn, P.J.

    1999-01-01

    The phases RE 2 BaCuO 5 /RE 4 Ba 2 Cu 2 O 10 phases (where RE is a mixture of Nd, Sm, Gd, Eu, Y and Yb) have been synthesized in an oxygen atmosphere and subsequently characterized. The mixing of RE elements which inherently form the RE 2 BaCuO 5 phase through the peritectic decomposition of REBa 2 Cu 3 O 7-x (RE123) (i.e. Sm, Gd, Eu, Y, Yb), was observed to give homogeneous mixing of the elements in the 211 phase. In contrast it was found that on mixing Nd with other RE elements a mixture of the Nd 4-2x Ba 2+2x Cu 2-x O 10-2x (Nd422) and RE 2 BaCuO 5 (RE211) phases resulted. It was also observed that on mixing Nd with other REs a finite amount of the RE is substituted into the Nd422 phase and Nd into the RE211. (author)

  8. Octupole excitations in 146Sm

    International Nuclear Information System (INIS)

    Bizzeti, P.G.; Bizzetti-Sona, A.M.

    1998-01-01

    The mean lives of the lowest 9 - and 12 + states of 146 Sm have been measured by means of the RDM. Their (preliminary) values are r m (9 - )=0.97±0.05 ns and r m (12 + )=15±2 ps, respectively. The strengths of the collective E3 transitions of the 12 + →9 - →6 6 cascade are compared with the corresponding ones in 148 Gd

  9. Ternary gallides RE_4Rh_9Ga_5, RE_5Rh_1_2Ga_7 and RE_7Rh_1_8Ga_1_1 (RE=Y, La-Nd, Sm, Gd, Tb). Intergrowth structures with MgCu_2 and CaCu_5 related slabs

    International Nuclear Information System (INIS)

    Seidel, Stefan; Rodewald, Ute C.; Poettgen, Rainer; Janka, Oliver

    2017-01-01

    Fourteen ternary gallides RE_4Rh_9Ga_5, RE_5Rh_1_2Ga_7 and RE_7Rh_1_8Ga_1_1 (RE=Y, La-Nd, Sm, Gd, Tb) were synthesized from the elements by arc-melting, followed by different annealing sequences either in muffle or induction furnaces. The samples were characterized through Guinier powder patterns and the crystal structures of Ce_4Rh_9Ga_5, Ce_5Rh_1_2Ga_7, Ce_7Rh_1_8Ga_1_1, Nd_5Rh_1_0_._4_4_(_4_)Ga_8_._5_6_(_4_), Nd_4Rh_9Ga_5 and Gd_4Rh_9Ga_5 were refined from single crystal X-ray diffractometer data. The new gallides are the n=2, 3 and 5 members of the RE_2_+_n Rh_3_+_3_n Ga_1_+_2_n structure series in the Parthe intergrowth concept. The slabs of these intergrowth structures derive from the cubic Laves phase MgCu_2 (Mg_2Ni_3Si as ternary variant) and CaCu_5 (CeCo_3B_2 as ternary variant). Only the Nd_5Rh_1_0_._4_4_(_4_)Ga_8_._5_6_(_4_) crystal shows Rh/Ga mixing within the Laves type slabs. Magnetic susceptibility measurements reveal Pauli paramagnetism for Y_4Rh_9Ga_5 and Curie-Weiss paramagnetism for Gd_4Rh_9Ga_5 and Tb_4Rh_9Ga_5. Low-temperature data show ferromagnetic ordering at T_C=78.1 (Gd_4Rh_9Ga_5) and 55.8 K (Tb_4Rh_9Ga_5).

  10. Determination of '14 MeV' cross sections for (n,p)-, (n,α)-, (n,2n)-, and (n,np + pn + d)-reactions on the elements Sc, Ni, Ge, Pd, Cd, Sm, Dy, Gd, and Yb in consideration of the 'effective' n-energy spectra

    International Nuclear Information System (INIS)

    Weigel, H.; Michel, R.; Herr, W.

    1975-01-01

    A total of 24 cross sections was determined for (n,p)-, (n,α)-, (n,2n)-, and (n,np + pn + d)-reactions of fast (so called '14 MeV') neutrons on the elements Sc, Ni, Ge, Pd, Cd, Sm, Dy, Gd, and Yb. 58 Ni(n,p) 58 Co served as monitor reaction. It is a special feature of this work that calculated neutron energy spectra for the '14 MeV' n-tube (Type Philips 18602) were considered, thus enabling us to supply each individual sigma-value with the respective n-energy distribution. On the basis of an extensive literature search (up to the beginning of 1973) the sigma-data were compared with experimental results of other authors and with those deduced from the statistical model. For some nuclides (e.g. 58 Ni, 154 Gd, 168 Yb, 176 Yb) it was possible to show the limits of applicability of the latter model. Summarizing, 12 cross sections and 3 isomeric ratios, nearly all of which belong to reaction products with rather long half-lifes, were determined for the first time. (orig.) [de

  11. Determination of '14 MeV' cross sections for (n,p), (n,. cap alpha. ), (n,2n), and (n,np + pn + d) reactions on the elements Sc, Ni, Ge, Pd, Cd, Sm, Dy, Gd, and Yb in consideration of the 'effective' n-energy spectra

    Energy Technology Data Exchange (ETDEWEB)

    Weigel, H; Michel, R; Herr, W [Koeln Univ. (F.R. Germany). Inst. fuer Kernchemie

    1975-01-01

    A total of 24 cross sections was determined for (n,p), (n,..cap alpha..), (n,2n), and (n,np + pn + d) reactions of fast (so called '14-MeV') neutrons on the elements Sc, Ni, Ge, Pd, Cd, Sm, Dy, Gd, and Yb. /sup 58/Ni(n,p)/sup 58/Co served as monitor reaction. It is a special feature of this work that calculated neutron energy spectra for the '14 MeV' n-tube (Type Philips 18602) were considered; each individual sigma value could thus be supplied with the respective n-energy distribution. On the basis of an extensive literature search (up to the beginning of 1973), the sigma data were compared with experimental results of other authors and with those deduced from the statistical model. For some nuclides (e.g. /sup 58/Ni, /sup 154/Gd, /sup 168/Yb, /sup 176/Yb) it was possible to show the limits of applicability of the latter model. Summarizing, 12 cross sections and 3 isomeric ratios, nearly all of which belong to reaction products with rather long half-lifes, were determined for the first time.

  12. Ternary gallides RE{sub 4}Rh{sub 9}Ga{sub 5}, RE{sub 5}Rh{sub 12}Ga{sub 7} and RE{sub 7}Rh{sub 18}Ga{sub 11} (RE=Y, La-Nd, Sm, Gd, Tb). Intergrowth structures with MgCu{sub 2} and CaCu{sub 5} related slabs

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, Stefan; Rodewald, Ute C.; Poettgen, Rainer [Univ. Muenster (Germany). Inst. fuer Anorganische und Analytische Chemie; Janka, Oliver [Univ. Oldenburg (Germany). Inst. fuer Chemie

    2017-07-01

    Fourteen ternary gallides RE{sub 4}Rh{sub 9}Ga{sub 5}, RE{sub 5}Rh{sub 12}Ga{sub 7} and RE{sub 7}Rh{sub 18}Ga{sub 11} (RE=Y, La-Nd, Sm, Gd, Tb) were synthesized from the elements by arc-melting, followed by different annealing sequences either in muffle or induction furnaces. The samples were characterized through Guinier powder patterns and the crystal structures of Ce{sub 4}Rh{sub 9}Ga{sub 5}, Ce{sub 5}Rh{sub 12}Ga{sub 7}, Ce{sub 7}Rh{sub 18}Ga{sub 11}, Nd{sub 5}Rh{sub 10.44(4)}Ga{sub 8.56(4)}, Nd{sub 4}Rh{sub 9}Ga{sub 5} and Gd{sub 4}Rh{sub 9}Ga{sub 5} were refined from single crystal X-ray diffractometer data. The new gallides are the n=2, 3 and 5 members of the RE{sub 2+n} Rh{sub 3+3n} Ga{sub 1+2n} structure series in the Parthe intergrowth concept. The slabs of these intergrowth structures derive from the cubic Laves phase MgCu{sub 2} (Mg{sub 2}Ni{sub 3}Si as ternary variant) and CaCu{sub 5} (CeCo{sub 3}B{sub 2} as ternary variant). Only the Nd{sub 5}Rh{sub 10.44(4)}Ga{sub 8.56(4)} crystal shows Rh/Ga mixing within the Laves type slabs. Magnetic susceptibility measurements reveal Pauli paramagnetism for Y{sub 4}Rh{sub 9}Ga{sub 5} and Curie-Weiss paramagnetism for Gd{sub 4}Rh{sub 9}Ga{sub 5} and Tb{sub 4}Rh{sub 9}Ga{sub 5}. Low-temperature data show ferromagnetic ordering at T{sub C}=78.1 (Gd{sub 4}Rh{sub 9}Ga{sub 5}) and 55.8 K (Tb{sub 4}Rh{sub 9}Ga{sub 5}).

  13. Strongly coupled band in 140Gd

    International Nuclear Information System (INIS)

    Falla-Sotelo, F.; Oliveira, J.R.B.; Rao, M.N.

    2005-01-01

    Several high-K states are known to exist in the mass 130-140 region. For the N=74 even-even isotopes, Kπ = 8 - isomers, with lifetimes ranging from ns to ms, are known in 128 Xe, 130 Ba, 132 Ce, 134 Nd, 136 Sm, and 138 Gd[. In 140 Gd, we have observed for the first time a band also based on an Iπ = 8 - state. This could be the first case of a Kπ = 8 - state observed in an N=76 even-even isotope. The systematics of the Kπ = 8 - isomeric states in N=74 isotopes has been studied by A.M. Bruce et al. These states decay towards the K = 0 ground state band, and the transitions are K-forbidden. The 140 Gd case presents strong similarities but also some significant differences with relation to the N=74 isotopes. We propose the same configuration but with larger deformation in 140 Gd

  14. Narrowing the gap: from semiconductor to semimetal in the homologous series of rare-earth zinc arsenides RE(2-y)Zn4As4·n(REAs) and Mn-substituted derivatives RE(2-y)Mn(x)Zn(4-x)As4·n(REAs) (RE = La-Nd, Sm, Gd).

    Science.gov (United States)

    Lin, Xinsong; Tabassum, Danisa; Mar, Arthur

    2015-12-14

    A homologous series of ternary rare-earth zinc arsenides, prepared by reactions of the elements at 750 °C, has been identified with the formula RE(2-y)Zn4As4·n(REAs) (n = 2, 3, 4) for various RE members. They adopt trigonal structures: RE(4-y)Zn4As6 (RE = La-Nd), space group R3̄m1, Z = 3; RE(5-y)Zn4As7 (RE = Pr, Nd, Sm, Gd), space group P3̄m1, Z = 1; RE(6-y)Zn4As8 (RE = La-Nd, Sm, Gd), space group R3̄m1, Z = 3. The Zn atoms can be partially substituted by Mn atoms, resulting in quaternary derivatives RE(2-y)Mn(x)Zn(4-x)As4·n(REAs). Single-crystal structures were determined for nine ternary and quaternary arsenides RE(2-y)M4As4·n(REAs) (M = Mn, Zn) as representative examples of these series. The structures are built by stacking close-packed nets of As atoms, sometimes in very long sequences, with RE atoms occupying octahedral sites and M atoms occupying tetrahedral sites, resulting in an intergrowth of [REAs] and [M2As2] slabs. The recurring feature of all members of the homologous series is a sandwich of [M2As2]-[REAs]-[M2As2] slabs, while rocksalt-type blocks of [REAs] increase in thickness between these sandwiches with higher n. Similar to the previously known related homologous series REM(2-x)As2·n(REAs) which is deficient in M, this new series RE(2-y)M4As4·n(REAs) exhibits deficiencies in RE to reduce the electron excess that would be present in the fully stoichiometric formulas. Enthalpic and entropic factors are considered to account for the differences in site deficiencies in these two homologous series. Band structure calculations indicate that the semiconducting behaviour of the parent n = 0 member (with CaAl2Si2-type structure) gradually evolves, through a narrowing of the gap between valence and conduction bands, to semimetallic behaviour as the number of [REAs] blocks increases, to the limit of n = ∞ for rocksalt-type REAs.

  15. Studies on Structural and Morphological Properties of Multidoped Ceria Ce0.8Nd0.0025Sm0.0025Gd0.005Dy0.095Y0.095O2-δ (x=0.2 as Solid Solutions

    Directory of Open Access Journals (Sweden)

    Marija Stojmenović

    2016-01-01

    Full Text Available The nanopowdery solid solutions of multidoped ceria Ce0.8Nd0.0025Sm0.0025Gd0.005Dy0.095Y0.095O2-δ (x=0.2 with the fluorite type crystal structure of CeO2 were synthesized for the first time. Two synthesis procedures were applied: the modified glycine-nitrate procedure (MGNP method and room temperature self-propagating reaction (SPRT method. All nanopowders were characterized by XRPD analysis, Raman spectroscopy, low temperature nitrogen physisorption, TEM, and SEM methods. According to the XRPD and Raman spectroscopy results, single phase solid solutions of fluorite structure were evidenced regardless of the number of dopants and synthesis procedure. Both XRPD and TEM were analyses evidenced nanometer particle dimensions. The SPRT method results in obtaining sample with higher specific surface area, smaller crystallite and particles sizes, and the same values of the lattice parameter in comparison to pure CeO2. Raman spectroscopy was confirmed to the oxygen vacancies introduced into the ceria lattice when Ce4+ ions were replaced with cations (dopants of lower valence state (3+, which may indicate the potential improvement of ionic conductivity. Additionally, the presence of oxygen vacancies in the lattice ceria, as well as very developed grain boundaries, gives a new possibility for potential application of obtained nanopowders in the area of room temperature ferromagnetism as spintronics.

  16. Ternary silicides ScIr{sub 4}Si{sub 2} and RERh{sub 4}Si{sub 2} (RE = Sc, Y, Tb-Lu) and quaternary derivatives RERh{sub 4}Si{sub 2-x}Sn{sub x} (RE = Y, Nd, Sm, Gd-Lu) - structure, chemical bonding, and solid state NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Vosswinkel, Daniel; Benndorf, Christopher; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Eckert, Hellmut [Muenster Univ. (Germany). Inst. fuer Physikalische Chemie; Sao Paulo Univ., Sao Carlos (Brazil). Inst. of Physics; Matar, Samir F. [Bordeaux Univ., CNRS, ICMCB, UPR 9048, Pessac (France)

    2016-11-01

    The silicides ScIr{sub 4}Si{sub 2} and RERh{sub 4}Si{sub 2} (RE = Sc, Y, Tb-Lu) and silicide stannides RERh{sub 4}Si{sub 2-x}Sn{sub x}(RE = Y, Nd, Sm, Gd-Lu) were synthesized from the elements by arc-melting and subsequent annealing. The new compounds crystallize with the orthorhombic YRh{sub 4}Ge{sub 2} type structure, space group Pnma. They were characterized by X-ray powder patterns and several structures were refined from single crystal X-ray diffractometer data. The main structural motifs of this series of silicides are tricapped trigonal prisms formed by the transition metal and rare earth atoms. One of the two crystallographically independent silicon sites allows for formation of solid solutions with tin, exemplarily studied for ErRh{sub 4}Si{sub 2-x}Sn{sub x}. Electronic structure calculations reveal strong covalent Rh-Si bonding as the main stability factor. Multinuclear ({sup 29}Si, {sup 45}Sc, and {sup 89}Y) magic-angle spinning (MAS) NMR spectra of the structure representatives with diamagnetic rare-earth elements (Sc, Y, Lu) are found to be consistent with the crystallographic data and specifically confirm the selective substitution of Sn in the Si2 sites in the quaternary compounds YRh{sub 4}SiSn and LuRh{sub 4}SiSn.

  17. L-shell X-ray production cross sections of Ce, Nd, Sm, Eu, Gd, and Dy by impact of {sup 14}N{sup 2+} ions with energies between 7.0 MeV and 10.5 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Murillo, G.; Méndez, B.; López-Monroy, J. [Departamento de Aceleradores, Instituto Nacional de Investigaciones Nucleares, Carr. México-Toluca S/N, Ocoyoacac, Edo. Méx. 52750 (Mexico); Miranda, J., E-mail: miranda@fisica.unam.mx [Instituto de Física, Universidad Nacional Autónoma de México, A.P. 20-364, México, Cd. Mx. 01000 (Mexico); Villaseñor, P. [Departamento de Aceleradores, Instituto Nacional de Investigaciones Nucleares, Carr. México-Toluca S/N, Ocoyoacac, Edo. Méx. 52750 (Mexico)

    2016-09-15

    Highlights: • A new data set of L X-ray production cross sections by nitrogen ion impact is given. • The target elements have atomic numbers in the range 58–66 (lanthanoids). • A universal scaling as function of a reduced velocity variable is applied. • The eCPSSR model with EC and MI corrections gives very good results. - Abstract: L-shell X-ray production cross sections from the lanthanoid elements Ce, Nd, Sm, Eu, Gd, and Dy, induced by the impact of {sup 14}N{sup 2+} ions with energies in the interval 7.0 MeV to 10.5 MeV (0.50 MeV/μ to 0.75 MeV/μ), were measured and then compared with theoretical calculations obtained with the ECPSSR model with exact limits of integration (eCPSSR) and related corrections. These include the electron capture by the incoming ion and multiple ionizations of higher shells. Data from this work were contrasted with previously published L X-ray production cross sections for {sup 14}N{sup 2+} ion impact. As with other ions, a universal behavior is found when L{sub α} and L{sub γ} X-ray production cross sections are plotted as a function of reduced velocity parameters. The agreement with theoretical predictions was very good when the corrections were applied to the eCPSSR model.

  18. Properties of the (Sm sub 0 sub . sub 3 sub 3 Eu sub 0 sub . sub 3 sub 3 Gd sub 0 sub . sub 3 sub 3)Ba sub 2 Cu sub 3 O sub y superconductor prepared by different processes in air

    CERN Document Server

    Giovannelli, F; Monot-Laffez, I

    2003-01-01

    Bars and pellets of the (Sm sub 0 sub . sub 3 sub 3 Eu sub 0 sub . sub 3 sub 3 Gd sub 0 sub . sub 3 sub 3)Ba sub 2 Cu sub 3 O sub x superconductor were processed in air, using the floating zone method and the top-seeded melt-textured growth method, respectively. The samples were prepared using different experimental conditions, i.e. maximal processing temperature, translation rate or cooling rate. Their physical properties and their microstructure were studied. All the samples exhibit a satisfying superconducting transition whereas the critical current density greatly depends on the processing parameters. The sample prepared by the floating zone method at 1070 deg C with a translation rate of 2 mm h sup - sup 1 exhibits a very high J sub c value of 70000 A cm sup - sup 2 in the self-field and more than 30000 A cm sup - sup 2 at 1.7 T. The pellet processed at 1080 deg C with a cooling rate of 2 deg C h sup - sup 1 has a high J sub c reaching about 56000 A cm sup - sup 2 in the self-field and more than 32000 A ...

  19. Studies on Structural and Morphological Properties of Multidoped Ceria Ce 0.8 Nd 0.0025 Sm 0.0025 Gd 0.005 Dy 0.095 Y 0.095 O 2 - δ ( x = 0.2 ) as Solid Solutions

    KAUST Repository

    Stojmenović, Marija

    2016-04-17

    The nanopowdery solid solutions of multidoped ceria Ce0.8Nd0.0025Sm0.0025Gd0.005Dy0.095Y0.095 () with the fluorite type crystal structure of CeO2 were synthesized for the first time. Two synthesis procedures were applied: the modified glycine-nitrate procedure (MGNP method) and room temperature self-propagating reaction (SPRT method). All nanopowders were characterized by XRPD analysis, Raman spectroscopy, low temperature nitrogen physisorption, TEM, and SEM methods. According to the XRPD and Raman spectroscopy results, single phase solid solutions of fluorite structure were evidenced regardless of the number of dopants and synthesis procedure. Both XRPD and TEM were analyses evidenced nanometer particle dimensions. The SPRT method results in obtaining sample with higher specific surface area, smaller crystallite and particles sizes, and the same values of the lattice parameter in comparison to pure CeO2. Raman spectroscopy was confirmed to the oxygen vacancies introduced into the ceria lattice when Ce4+ ions were replaced with cations (dopants) of lower valence state (3+), which may indicate the potential improvement of ionic conductivity. Additionally, the presence of oxygen vacancies in the lattice ceria, as well as very developed grain boundaries, gives a new possibility for potential application of obtained nanopowders in the area of room temperature ferromagnetism as spintronics.

  20. Carbonitrides in the system Ta-TaC-TaN

    International Nuclear Information System (INIS)

    Ritzhaupt-Kleissl, H.J.

    1975-04-01

    Specimens have been prepared in the binary section TaC-TaN and the carbon-rich region of the Ta-TaC-TaN system by hot pressing and subsequent homogenisation. It was possible to prepare nitrogen-rich carbonitrides by homogenizing them at 1,800 0 C under a nitrogen-pressure of 50 at up to the composition of 70 mol% TaN/30 mol% TaC. Those carbonitrides containing less than 25 at% nitrogen could be prepared by homogenisation at 2,000 0 C under a nitrogen-pressure of 600 Torr. Subsequent ageing at temperatures of 1,200, 1,300 and 1,400 0 C in high vacuum as well as at 1 at nitrogen resulted in the appearance of precipitations of epsilon-TaN, β-Ta 2 (C,N) and of the zeta-phase. The type amount and shape of the precipitated phases are dependent on the ageing conditions and on the composition the specimens. Single phase specimens with compositions close to the non-metal deficient phase boundary as well as multi-phase carbonitrides with high nitrogen contents and very fine precipitates showed values of the Vickers-hardness up to 3,000 kp/mm 2 at room temperature. With regard to the hot hardness up to a temperature of 1,300 0 C specimens aged in high vacuum were superior to those which were only homogenized as well as to those aged under a nitrogen-pressure of 1 at. On an average the best hardness-values have been found at room temperature as well as at temperatures up to 1,300 0 C for carbonitrides consisting of 50 mol% TaC/50 mol% TaN after homogenisation and subsequent ageing for 40 h at 1,300 0 C. (orig.) [de

  1. Strategisch management (SM)

    NARCIS (Netherlands)

    Nagel, A.P.; Vercouteren, W.J.J.C.; Hoek, van der N.; Lohman, T.A.M.; Vermeulen, N.

    1996-01-01

    Kernbegrippen die bij de discussie van strategisch management (SM) aan de orde komen, zijn productinnovatie op ondernemingsniveau (oftewel strategische productinnovatie, SPI) en technologiestrategie. In dit artikel wordt een raamwerk van SM geintroduceerd. Daartoe worden de verschillende fasen van

  2. Synthesis, structures, and luminescent properties of sodium rare-earth metal(III) chloride oxotellurates(IV), Na{sub 2}Ln{sub 3}Cl{sub 3}[TeO{sub 3}]{sub 4} (Ln = Sm, Eu, Gd, Tb, Dy, and Ho)

    Energy Technology Data Exchange (ETDEWEB)

    Charkin, Dmitri O.; Dorofeev, Sergey G.; Berdonosov, Peter S.; Dolgikh, Valery A. [Department of Chemistry, Lomonosov Moscow State University (Russian Federation); Zitzer, Sabine; Greiner, Stefan; Schleid, Thomas [Institut fuer Anorganische Chemie, Universitaet Stuttgart (Germany); Olenev, Andrei V. [Department of Chemistry, Lomonosov Moscow State University (Russian Federation); Sine Theta Ltd., Moscow (Russian Federation)

    2017-11-17

    Six sodium rare-earth metal(III) chloride oxotellurates(IV), Na{sub 2}Ln{sub 3}Cl{sub 3}[TeO{sub 3}]{sub 4}, isostructural to Na{sub 2}Y{sub 3}Cl{sub 3}[TeO{sub 3}]{sub 4}, were synthesized by flux techniques and characterized by single-crystal XRD. The compounds crystallize in the monoclinic space group C2/c with lattice constants a = 23.967(1), b = 5.6342(3), c = 16.952(1) Aa, β = 134.456(5) for Ln = Sm, a = 23.932(2), b = 5.6044(5), c = 17.134(1) Aa, β = 135.151(6) for Ln = Eu, a = 23.928(1), b = 5.5928(1), c = 17.1133(8) Aa, β = 135.366(3) for Ln = Gd, a = 23.907(1), b = 5.569(3), c = 16.745(1) Aa, β = 134.205(3) for Ln = Tb, a = 23.870(1), b = 5.547(3), c = 16.665(1) Aa, β = 134.102(3) for Ln = Dy, and a = 23.814(1), b = 5.526(3), c = 16.626(1) Aa, β = 134.016(3) for Ln = Ho and Z = 4. Their crystal structure can be considered as a framework built of intergrowing Ln-O and Na-(O,Cl) slabs with channel walls decorated by tellurium atoms of [TeO{sub 3}]{sup 2-} groups. The luminescent properties of the new compounds due to the Ln{sup 3+} cations are described and discussed. We also discuss the crystal chemistry of various alkali-metal rare-earth metal(III) halide oxochalcogenates(IV). (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Web TA Production (WebTA)

    Data.gov (United States)

    US Agency for International Development — WebTA is a web-based time and attendance system that supports USAID payroll administration functions, and is designed to capture hours worked, leave used and...

  4. Structural trends in a series of isostructural lanthanide-copper metallacrown sulfates (Ln(III) = Pr, Nd, Sm, Eu, Gd, Dy and Ho): hexaaquapentakis[μ3-glycinehydroxamato(2-)]sulfatopentacopper(II)lanthanide(III) heptaaquapentakis[μ3-glycinehydroxamato(2-)]sulfatopentacopper(II)lanthanide(III) sulfate hexahydrate.

    Science.gov (United States)

    Pavlishchuk, Anna V; Kolotilov, Sergey V; Fritsky, Igor O; Zeller, Matthias; Addison, Anthony W; Hunter, Allen D

    2011-07-01

    The seven isostructural complexes, [Cu(5)Ln(C(2)H(4)N(2)O(2))(5)(SO(4))(H(2)O)(6.5)](2)(SO(4))·6H(2)O, where Ln(III) = Pr, Nd, Sm, Eu, Gd, Dy and Ho, are representatives of the 15-metallacrown-5 family. Each dianion of glycinehydroxamic acid (GlyHA) links two Cu(II) cations forming a cyclic [CuGlyHA](5) frame. The Ln(III) cations are located at the centre of the [CuGlyHA](5) rings and are bound by the five hydroxamate O atoms in the equatorial plane. Five water molecules are coordinated to Cu(II) cations, and one further water molecule, located close to an inversion centre between two adjacent [Cu(5)Ln(GlyHA)(5)](2+) cations, is disordered around this inversion centre and coordinated to a Cu(II) cation of either the first or second metallacrown ether. Another water molecule and one of the two crystallographically independent sulfate anions are coordinated, the latter in a bidentate fashion, to the Ln(III) cation in the axial positions. The second sulfate anion is not coordinated to the cation, but is located in an interstitial position on a crystallographic inversion centre, thus leading to disorder of the O atoms around the centre of inversion. The Ln-O bond distances follow the trend of the lanthanide contraction. The apical Ln-O bond distances are very close to the sums of the ionic radii. However, the Ln-O distances within the metallacrown units are slightly compressed and the Ln(III) cations protrude significantly from the plane of the otherwise flat metallacrown ligand, thus indicating that the cavity is somewhat too small to accommodate the Ln(III) ions comfortably. This effect decreases with the size of the lanthanide cation from complex (I) (Ln(III) = Pr; 0.459) to complex (VII) (Ln(III) = Ho; 0.422), which indicates that the smaller lanthanide cations fit the cavity of the pentacopper metallacrown ring better than the larger ones. The diminished contraction of Ln-O distances within the metallacrown planes leads to an aniostropic contraction of the unit

  5. Solvothermal syntheses, crystal structures, and properties of lanthanide(III) thioarsenates [Ln(dien)2(μ-1κ,2κ2-AsS4)]n (Ln==Sm, Eu, Gd) and [Ln(dien)2(1κ2-AsS4)] (Ln==Tb, Dy, Ho)

    International Nuclear Information System (INIS)

    Wang, Fang; Tang, Chunying; Chen, Ruihong; Zhang, Yong; Jia, Dingxian

    2013-01-01

    Solvothermal reactions of Ln 2 O 3 , As and S in diethylenetriamine (dien) at 170 °C for 6 days afforded two structural types of lanthanide thioarsenates with the general formulae [Ln(dien) 2 (μ-1κ,2κ 2 -AsS 4 )] n [Ln=Sm(1), Eu(2), Gd(3)] and [Ln(dien) 2 (1κ 2 -AsS 4 )] [Ln=Tb(4), Dy(5), Ho(6)]. The Ln 2 O 3 oxides were converted to [Ln(dien) 2 ] 3+ complex units in the solvothermal reactions. The As atom binds four S atoms, forming a tetrahedral AsS 4 unit. In 1−3, the AsS 4 units interconnect the [Ln(dien) 2 ] 3+ cations via Ln−S bonds as tridentate μ-1κ,2κ 2 -AsS 4 bridging ligands, resulting in the neutral coordination polymers [Ln(dien) 2 (μ-1κ,2κ 2 -AsS 4 )] n (Ln1). In 4−6, the AsS 4 units coordinate with the Ln 3+ ion of [Ln(dien) 2 ] 3+ as 1κ 2 -AsS 4 chelating ligands to form neutral coordination compounds [Ln(dien) 2 (1κ 2 -AsS 4 )] (Ln2). The Ln 3+ ions are in nine- and eight-coordinated environments in Ln1 and Ln2, respectively. The formation of Ln1 and Ln2 is related with ionic size of the Ln 3+ ions. Optical absorption spectra showed that 1−6 have potential use as semiconductors with the band gaps in the range 2.18−3.21 eV. - Graphical abstract: Two types of Ln-thioarsenates [Ln(dien) 2 (μ-1κ,2κ 2 -AsS 4 )] n and [Ln(dien) 2 (1κ 2 -AsS 4 )] were prepared by solvothermal methods and the soft Lewis basic AsS 4 3– ligand to Ln(III) centers with polyamine co-ligand was obtained. Display Omitted - Highlights: • Lanthanide thioarsenates were prepared by solvothermal methods. • The soft Lewis basic AsS 4 ligand coordinate Ln 3+ ions with coexistence polyamine ligands. • Two structural types of Ln-thioarsenates with structural turnover at Tb were obtained along Ln series. • The Ln-thioarsenates are potential semiconductors with optical band gaps in the range 2.18−3.21 eV

  6. Two hexagonal series of lanthanoid(III) oxide fluoride selenides.: M{sub 6}O{sub 2}F{sub 8}Se{sub 3} (M = La - Nd) and M{sub 2}OF{sub 2}Se (M = Nd, Sm, Gd - Ho)

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, Dirk D.; Grossholz, Hagen; Wolf, Sarah; Schleid, Thomas [Institut fuer Anorganische Chemie, Universitaet Stuttgart (Germany); Janka, Oliver [Institut fuer Anorganische Chemie, Universitaet Stuttgart (Germany); Institut fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Universitaet Muenster (Germany); Mueller, Alexander C. [Institut fuer Anorganische Chemie, Universitaet Stuttgart (Germany); Institut fuer Textilchemie und Chemiefasern, Denkendorf (Germany)

    2015-09-15

    Two hexagonal series of lanthanoid(III) oxide fluoride selenides with similar structure types can be obtained by the reaction of the components MF{sub 3}, M{sub 2}O{sub 3}, M, and Se in sealed niobium tubes at 850 C using CsI as fluxing agent. The compounds with the lighter and larger representatives (M = La - Nd) occur with the formula M{sub 6}O{sub 2}F{sub 8}Se{sub 3}, whereas with the heavier and smaller ones (M = Nd, Sm, Gd - Ho) their composition is M{sub 2}OF{sub 2}Se. For both systems single-crystal determinations were used in all cases. The compounds crystallize in the hexagonal crystal system (space group: P6{sub 3}/m) with lattice parameters of a = 1394-1331 pm and c = 403-372 pm (Z = 2 for M{sub 6}O{sub 2}F{sub 8}Se{sub 3} and Z = 6 for M{sub 2}OF{sub 2}Se). The (M1){sup 3+} cations show different square antiprismatic coordination spheres with or without an extra capping fluoride anion. All (M2){sup 3+} cations exhibit a ninefold coordination environment shaped as tricapped trigonal prism. In both structure types the Se{sup 2-} anions are sixfold coordinated as trigonal prisms of M{sup 3+} cations, being first condensed by edges to generate trimeric units and then via faces to form strands running along [001]. The light anions reside either in threefold triangular or in fourfold tetrahedral cationic coordination. For charge compensation, both structures have to contain a certain amount of oxide besides fluoride anions. Since F{sup -} and O{sup 2-} can not be distinguished by X-ray diffraction, bond-valence calculations were used to address the problem of their adjunction to the available crystallographic sites. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Strongly coupled band in {sup 140}Gd

    Energy Technology Data Exchange (ETDEWEB)

    Falla-Sotelo, F.; Oliveira, J.R.B.; Rao, M.N. [Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo (Brazil)] (and others)

    2005-07-01

    Several high-K states are known to exist in the mass 130-140 region. For the N=74 even-even isotopes, K{pi} = 8{sup -} isomers, with lifetimes ranging from ns to ms, are known in {sup 128}Xe, {sup 130}Ba, {sup 132}Ce, {sup 134}Nd, {sup 136}Sm, and {sup 138}Gd[. In {sup 140}Gd, we have observed for the first time a band also based on an I{pi} = 8{sup -} state. This could be the first case of a K{pi} = 8{sup -} state observed in an N=76 even-even isotope. The systematics of the K{pi} = 8{sup -} isomeric states in N=74 isotopes has been studied by A.M. Bruce et al. These states decay towards the K = 0 ground state band, and the transitions are K-forbidden. The {sup 140}Gd case presents strong similarities but also some significant differences with relation to the N=74 isotopes. We propose the same configuration but with larger deformation in {sup 140}Gd.

  8. Solvothermal syntheses, crystal structures, and properties of lanthanide(III) thioarsenates [Ln(dien){sub 2}(μ-1κ,2κ{sup 2}-AsS{sub 4})]{sub n} (Ln==Sm, Eu, Gd) and [Ln(dien){sub 2}(1κ{sup 2}-AsS{sub 4})] (Ln==Tb, Dy, Ho)

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Fang; Tang, Chunying; Chen, Ruihong; Zhang, Yong; Jia, Dingxian, E-mail: jiadingxian@suda.edu.cn

    2013-10-15

    Solvothermal reactions of Ln{sub 2}O{sub 3}, As and S in diethylenetriamine (dien) at 170 °C for 6 days afforded two structural types of lanthanide thioarsenates with the general formulae [Ln(dien){sub 2}(μ-1κ,2κ{sup 2}-AsS{sub 4})]{sub n} [Ln=Sm(1), Eu(2), Gd(3)] and [Ln(dien){sub 2}(1κ{sup 2}-AsS{sub 4})] [Ln=Tb(4), Dy(5), Ho(6)]. The Ln{sub 2}O{sub 3} oxides were converted to [Ln(dien){sub 2}]{sup 3+} complex units in the solvothermal reactions. The As atom binds four S atoms, forming a tetrahedral AsS{sub 4} unit. In 1−3, the AsS{sub 4} units interconnect the [Ln(dien){sub 2}]{sup 3+} cations via Ln−S bonds as tridentate μ-1κ,2κ{sup 2}-AsS{sub 4} bridging ligands, resulting in the neutral coordination polymers [Ln(dien){sub 2}(μ-1κ,2κ{sup 2}-AsS{sub 4})]{sub n} (Ln1). In 4−6, the AsS{sub 4} units coordinate with the Ln{sup 3+} ion of [Ln(dien){sub 2}]{sup 3+} as 1κ{sup 2}-AsS{sub 4} chelating ligands to form neutral coordination compounds [Ln(dien){sub 2}(1κ{sup 2}-AsS{sub 4})] (Ln2). The Ln{sup 3+} ions are in nine- and eight-coordinated environments in Ln1 and Ln2, respectively. The formation of Ln1 and Ln2 is related with ionic size of the Ln{sup 3+} ions. Optical absorption spectra showed that 1−6 have potential use as semiconductors with the band gaps in the range 2.18−3.21 eV. - Graphical abstract: Two types of Ln-thioarsenates [Ln(dien){sub 2}(μ-1κ,2κ{sup 2}-AsS{sub 4})]{sub n} and [Ln(dien){sub 2}(1κ{sup 2}-AsS{sub 4})] were prepared by solvothermal methods and the soft Lewis basic AsS{sub 4}{sup 3–} ligand to Ln(III) centers with polyamine co-ligand was obtained. Display Omitted - Highlights: • Lanthanide thioarsenates were prepared by solvothermal methods. • The soft Lewis basic AsS{sub 4} ligand coordinate Ln{sup 3+} ions with coexistence polyamine ligands. • Two structural types of Ln-thioarsenates with structural turnover at Tb were obtained along Ln series. • The Ln-thioarsenates are potential semiconductors

  9. Neutron cross section measurements using the ORELA: 86Kr(n,x), 40Ca(n,x), 22Ne(n,γ), 189Os(n,n'), 186187188189Os(n,x), 189Os(n,γ), 148149150Sm(n,γ), 179Ta(n,γ), 868788Sr(n,x), 40Ar(n,x), the stable tellurium isotopes (n,γ) and 205Tl(n,x). Progress report, September 1, 1983-August 31, 1984

    International Nuclear Information System (INIS)

    Winters, R.R.

    1984-09-01

    The research performed during this reporting period has resulted in (1) publication of two papers dealing with the optical model and with 187 Os(n,n') for astrophysics; (2) preparation and submission of two papers describing measurements of 148 149 150 Sm(n,γ) and 60 Ni(n,x) cross sections; (3) mesurement of the 189 Os(n,n') cross sections at energies of astrophysical interest; (4) measurement of the 189 Os(n,γ) cross sections over a range of energies pertinent to astrophysical interest; (5) extraction of the tantalum target from an ORELA target assembly and arranging shipment of the radioactive tantalum to Kernforschungszentrum, West Germany, in preparation for a measurement of the 179 Ta(n,γ) cross sections; and (6) acquistion of a smart terminal computer workstation. Preliminary results from our 189 Os measurements are consistent with the cross sections calculated using the same optical model reported by Hershberger et al. for 187 Os. Hence the effect of the first excited state in 187 Os on the use of the Re/Os beta decay as a stellar nucleosynthesis chronometer is very nearly as estimated by Woosley and Fowler. The duration of galactic nucleosynthesis is now estimated from the Re/Os chronmeter as approx. 11.3 byr. and the age of the universe as approx. 17 byr. 19 references

  10. Gd-Ni-Si system

    International Nuclear Information System (INIS)

    Bodak, O.I.; Shvets, A.F.

    1983-01-01

    By X-ray phase analysis method isothermal cross section of phase diagram of the Gd-Ni-Si system at 870 K is studied. The existence of nine previously known compounds (GdNisub(6.72)Sisub(6.28), GdNi 10 Si 2 , GdNi 5 Si 3 , GdNi 4 Si, GdNi 2 Si 2 , GdNiSi 3 , GdNiSi 2 , Gd 3 Ni 6 Si 2 and GdNiSi) is confirmed and three new compounds (GdNisub(0.2)Sisub(1.8), Gdsub(2)Nisub(1-0.8)Sisub(1-1.2), Gd 5 NiSi 4 ) are found. On the base of Gd 2 Si 3 compound up to 0.15 at. Ni fractions, an interstitial solid solution is formed up to 0.25 at Ni fractions dissolution continues of substitution type. The Gd-Ni-Si system is similar to the Y-Ni-Si system

  11. Signature inversion of the semi-decoupled band in the odd-odd nucleus 170Ta

    International Nuclear Information System (INIS)

    Deng Fuguo; Yang Chunxiang; Zhou Hongyu; Sun Huibin; Lu Jingbin; Zhao Guangyi; Yin Lichang; Liu Yunzuo

    2001-01-01

    The high-spin states of the odd-odd nucleus 170 Ta have been studied by the 155 Gd( 19 F, 4n) 170 Ta reaction at the beam energy of 97 MeV. The α = 1 sequence of the semi-decoupled band has been pushed to higher-spin states and the signature inversion point was observed at 19.5 ℎ. the results are compared with those of the neighbouring odd-odd nuclei

  12. Radiological soil survey adjacent to TA-35, TA-48, TA-50, and TA-55

    International Nuclear Information System (INIS)

    Purtymun, W.D.; Becker, N.M.; Maes, M.N.

    1985-01-01

    The 137 Cs concentrations in soil from five new locations (in technical areas where radioactive materials are processed or have been processed) are at or below the maximum levels (1.4 pCi/g) found in regional soils. The 238 Pu and /sup 239,240/Pu soil concentrations at Station 2 were greater than were those found in regional soils (1977 and 1978-1982 Summaries). Station 2 is located south of TA-50. The total uranium soil concentrations exceed regional background concentrations at all stations. However, these levels do not indicate contamination but reflect natural uranium leached from soil derived from the tuff. These concentrations are similar to the data collected in 1977. Uranium concentrations in soils vary and depend on the rock type that has weathered to form the soil. A comparison of the averages and standard deviations of radiochemical analyses collected in 1977 and 1983 indicates only slight variations between the 2 yr. The five new stations established in 1983 will provide long-term monitoring of the possible airborne deposition of contaminants in the areas around TA-35, TA-48, TA-50, and TA-55. Comparing 1977 with 1983 data indicates no significant increase in radioactivity of the soil adjacent to these technical areas

  13. Superconductivity and magnetism in Ir-doped GdFeAsO

    International Nuclear Information System (INIS)

    Cui, Y.J.; Chen, Y.L.; Cheng, C.H.; Yang, Y.; Jiang, J.; Wang, Y.Z.; Zhang, Y.; Zhao, Y.

    2010-01-01

    The 5d-transition metal, Ir has successfully been doped at Fe site and induced superconductivity in GdFeAsO at T c = 18.9 K and ∼20 atom%. The Ir-doping shortened the c-axis length and stretched the a-axis one, which led to enhance the coupling between the FeAs- and SmO-layer, and to weaken the bonding between Fe and As atom. Paramagnetism was observed in all of the samples, which was resulted from the magnetic Gd ion as in the F-doped GdFeAsO. An upper critical field of GdFe 0.8 Ir 0.2 AsO was extrapolated to around 24 T, much smaller than that of F-doped GdFeAsO owing to a relatively low T c and small value of dH c2 /dT.

  14. The volumetric and thermochemical properties of YCl{sub 3}(aq), YbCl{sub 3}(aq), DyCl{sub 3}(aq), SmCl{sub 3}(aq), and GdCl{sub 3}(aq) at T=(288.15, 298.15, 313.15, and 328.15) K and p=0.1 MPa[Trivalent metal chlorides; Densities; Heat capacities; Single ion properties; Calorimetry; Densimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hakin, Andrew W. E-mail: hakin@uleth.ca; Lukacs, Michael J.; Liu, Jin Lian; Erickson, Kristy

    2003-11-01

    Relative densities and massic heat capacities have been measured for acidified aqueous solutions of YCl{sub 3}(aq), YbCl{sub 3}(aq), DyCl{sub 3}(aq), SmCl{sub 3}(aq), and GdCl{sub 3}(aq) at T=(288.15, 298.15, 313.15, and 328.15) K and p=0.1 MPa. These measurements have been used to calculate experimental apparent molar volumes and heat capacities which, when used in conjunction with Young's rule, were used to calculate the apparent molar properties of the aqueous chloride salt solutions. The latter calculations required the use of volumetric and thermochemical data for aqueous solutions of hydrochloric acid that have been previously reported in the literature. The concentration dependences of the apparent molar properties have been modeled using Pitzer ion interaction equations to yield apparent molar volumes and heat capacities at infinite dilution. The temperature and concentration dependences of the apparent molar volumes and heat capacities of each trivalent salt system were modeled using modified Pitzer ion interaction equations. These equations utilized the revised Helgeson, Kirkham, and Flowers equations of state to model the temperature dependences of apparent molar volumes and heat capacities at infinite dilution. Calculated apparent molar volumes and heat capacities at infinite dilution have been used to calculate single ion properties for the investigated trivalent metal cations. These values have been compared to those previously reported in the literature. The differences between single ion values calculated in this study and those values calculated from thermodynamic data for aqueous perchlorate salts are also discussed.

  15. Spectroscopy of 169Ta

    International Nuclear Information System (INIS)

    Kshetri, Ritesh; Ray, I.; Ganguly, S.; Pradhan, M.K.; Raut, R.; Goswami, A.; Banerjee, P.; Mukherjee, A.; Datta Pramanik, U.; Bhattacharya, S.; Dasmahapatra, B.; Saha Sarkar, M.; Dey, G.; Ray Basu, M.; Krishichayan; Chakraborty, A.; Ghugre, S.S.; Ray, M.; Sarkar, S.

    2006-01-01

    The lifetimes of the isomeric levels of 169,171 Ta have been re-measured using the centroid shift method of electronic timing technique. Preliminary results for lifetimes are in good agreement with the adopted values. Investigations are being carried out to identify other isomeric levels

  16. Charge Carrier Trapping Processes in RE2O2S (RE = La, Gd, Y, and Lu)

    NARCIS (Netherlands)

    Luo, H.; Bos, A.J.J.; Dorenbos, P.

    2017-01-01

    Two different charge carrier trapping processes have been investigated in RE2O2S:Ln3+ (RE = La, Gd, Y, and Lu; Ln = Ce, Pr, and Tb) and RE2O2S:M (M = Ti4+ and Eu3+). Cerium, praseodymium and terbium act as recombination centers and hole trapping centers while host intrinsic defects provide the

  17. The temperature dependence studies of rare-earth (Dy.sup.3+./sup., Sm.sup.3+./sup., Eu.sup.3+./sup. and Tb.sup.3+./sup.) activated Gd.sub.3./sub.Ga.sub.3./sub.Al.sub.2./sub.O.sub.12./sub. garnet single crystals

    Czech Academy of Sciences Publication Activity Database

    Bartosiewicz, Karol; Babin, Vladimir; Beitlerová, Alena; Boháček, Pavel; Jurek, Karel; Nikl, Martin

    2017-01-01

    Roč. 189, Sep (2017), s. 126-139 ISSN 0022-2313 R&D Projects: GA ČR GA16-15569S EU Projects: European Commission(XE) 316906 - LUMINET Institutional support: RVO:68378271 Keywords : Gd3Ga3Al2O12 * rare earth dopants * energy transfer * thermal quenching * single crystal Sub ject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 2.686, year: 2016

  18. SM18 Visits and Access

    CERN Multimedia

    2012-01-01

      VISITS The rules and conditions to be followed for visits in the SM18 Hall are laid out in the EDMS 1205328 document. No visit is allowed without prior reservation.   ACCESS Special access right is needed ONLY from 7 p.m. to 7 a.m. and during week-ends. From 1 December, the current SM18 access database will be closed and a new one “SM18-OWH outside normal hours” started from scratch. Requests, via EDH SM18-OWH, will have to be duly justified.   For further information, please contact Evelyne Delucinge.

  19. Ultraviolet photoluminescence in Gd-doped silica and phosphosilicate fibers

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2017-04-01

    Full Text Available Optical fiber lasers operating in the near infrared and visible spectral regions have relied on the spectroscopic properties of rare earth ions such as Yb3+, Er3+, Tm3+, Nd3+, and Sm3+. Here, we investigate Gd3+ doping in phosphosilicate and pure silica fibers using solution doping and sol-gel techniques, respectively, for potential applications in the ultraviolet. Photoluminescence spectra for optical fiber bundles and fiber preforms were recorded and compared. Emissions at 312 nm (phosphosilicate and 314 nm (pure silica were observed when pumping to the Gd3+ 6DJ, 6IJ, and 6PJ = 5/2, 3/2 energy levels. Oxygen deficient center was observed in solution doping sample with a wide absorption band centered at around 248 nm not affecting pumping to 6IJ states.

  20. Study of Gd lattices

    International Nuclear Information System (INIS)

    Vidovsky, I.; Kereszturi, A.

    1991-11-01

    The results of experiments and calculations on Gd lattices are presented, and a comparison of experimental and calculational data is given. This latter can be divided into four groups. The first belongs to the comparison of criticality parameters, the second group is related with the comparison of 2D distributions, the third one relates the comparison of intra-macrocell distributions, whereas the fourth group is devoted for the comparison of spectral parameters. For comparison, the computer code RFIT based on strict statistical criteria has been used. The calculated and measured results agree, in most cases, sufficiently. (R.P.) 11 refs.; 13 figs.; 9 tabs

  1. 24/7 SM slavery.

    Science.gov (United States)

    Dancer, Peter L; Kleinplatz, Peggy J; Moser, Charles

    2006-01-01

    This study describes the nature of 24/7 SM slavery as practiced within the SM (sadomasochistic) community. These SM participants, who attempt to live full-time in owner-slave roles, represent a small proportion of those with SM interests. SM slaves have not been studied systematically to determine if and how they differ from other SM practitioners. An online questionnaire was used to obtain responses from individuals who self-identified as slaves. A total of 146 respondents participated, 53% female and 47% male, ranging in age from 18 to 72. We explored the depth of their relationships, how well they approximated "slavery," and how their relationships were structured to maintain distinct roles. Data showed that in long-term SM slave relationships, a power differential exists which extends beyond time-limited SM or sexual interactions. Owners and slaves often use common, daily life experiences or situations, such as the completion of household chores, money management, and morning or evening routines, to distinguish and maintain their respective roles. In addition, contrary to the perception of total submission, results revealed that slaves exercise free will when it is in their best interests to do so. These relationships were long-lasting and satisfying to the respondents.

  2. Comparative study of Ta, TaN and Ta/TaN bi-layer barriers for Cu-ultra low-k porous polymer integration

    International Nuclear Information System (INIS)

    Yang, L.Y.; Zhang, D.H.; Li, C.Y.; Foo, P.D.

    2004-01-01

    Tantalum (Ta), TaN and bilayer Ta/TaN barriers deposited on ultra-low-k porous polymer (ULKPP) and the thermal stability of their structures are comparatively investigated using various techniques. The Ta/ultra-low-k polymer shows the smallest sheet resistance, but the poorest thermal stability, while TaN on the ultra-low-k polymer shows the highest resistance but the best thermal stability. The bi-layer Ta/TaN barrier takes the advantage of both Ta and TaN barriers and gives reasonable resistance and thermal stability. The electrical tests indicate that the Cu lines with the TaN and bi-layer Ta/TaN barriers exhibit the smaller leakage current and higher breakdown voltage compared with the Cu lines with the Ta barrier. The better thermal stability of the TaN and the bi-layer Ta/TaN barriers is mainly due to the amorphous/nanostructure and less grain boundaries of the barriers. In addition, the texture discontinuity at the Ta/TaN interfaces in the bi-layers barrier also plays an important role in reducing mutual diffusion of Ta atoms in the Ta barrier and some atoms in the ultra-low-k porous polymer

  3. Investigation of TaC–TaB2 ceramic composites

    Indian Academy of Sciences (India)

    ture and the mechanical properties of the composites were investigated. The results .... 300 nm. Jingangzuan in the TaC/TaB2 composites SPS for 10 min at different temperatures are .... [1] Liu L, Yea F, Hea X and Zhoua Y 2011 Mater. Chem.

  4. Structure-function analysis and genetic interactions of the SmG, SmE, and SmF subunits of the yeast Sm protein ring.

    Science.gov (United States)

    Schwer, Beate; Kruchten, Joshua; Shuman, Stewart

    2016-09-01

    A seven-subunit Sm protein ring forms a core scaffold of the U1, U2, U4, and U5 snRNPs that direct pre-mRNA splicing. Using human snRNP structures to guide mutagenesis in Saccharomyces cerevisiae, we gained new insights into structure-function relationships of the SmG, SmE, and SmF subunits. An alanine scan of 19 conserved amino acids of these three proteins, comprising the Sm RNA binding sites or inter-subunit interfaces, revealed that, with the exception of Arg74 in SmF, none are essential for yeast growth. Yet, for SmG, SmE, and SmF, as for many components of the yeast spliceosome, the effects of perturbing protein-RNA and protein-protein interactions are masked by built-in functional redundancies of the splicing machine. For example, tests for genetic interactions with non-Sm splicing factors showed that many benign mutations of SmG, SmE, and SmF (and of SmB and SmD3) were synthetically lethal with null alleles of U2 snRNP subunits Lea1 and Msl1. Tests of pairwise combinations of SmG, SmE, SmF, SmB, and SmD3 alleles highlighted the inherent redundancies within the Sm ring, whereby simultaneous mutations of the RNA binding sites of any two of the Sm subunits are lethal. Our results suggest that six intact RNA binding sites in the Sm ring suffice for function but five sites may not. © 2016 Schwer et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  5. Structure–function analysis and genetic interactions of the SmG, SmE, and SmF subunits of the yeast Sm protein ring

    Science.gov (United States)

    Schwer, Beate; Kruchten, Joshua; Shuman, Stewart

    2016-01-01

    A seven-subunit Sm protein ring forms a core scaffold of the U1, U2, U4, and U5 snRNPs that direct pre-mRNA splicing. Using human snRNP structures to guide mutagenesis in Saccharomyces cerevisiae, we gained new insights into structure–function relationships of the SmG, SmE, and SmF subunits. An alanine scan of 19 conserved amino acids of these three proteins, comprising the Sm RNA binding sites or inter-subunit interfaces, revealed that, with the exception of Arg74 in SmF, none are essential for yeast growth. Yet, for SmG, SmE, and SmF, as for many components of the yeast spliceosome, the effects of perturbing protein–RNA and protein–protein interactions are masked by built-in functional redundancies of the splicing machine. For example, tests for genetic interactions with non-Sm splicing factors showed that many benign mutations of SmG, SmE, and SmF (and of SmB and SmD3) were synthetically lethal with null alleles of U2 snRNP subunits Lea1 and Msl1. Tests of pairwise combinations of SmG, SmE, SmF, SmB, and SmD3 alleles highlighted the inherent redundancies within the Sm ring, whereby simultaneous mutations of the RNA binding sites of any two of the Sm subunits are lethal. Our results suggest that six intact RNA binding sites in the Sm ring suffice for function but five sites may not. PMID:27417296

  6. Optical isotype shifts of 146Sm and 151Sm

    International Nuclear Information System (INIS)

    Eastham, D.A.; Walker, P.M.; Griffith, J.A.R.; Evans, D.E.; England, J.G.; Grant, I.S.

    1984-01-01

    We have measured the optical isotope shifts of 146 Sm and 151 Sm by laser resonance fluorescence. From these measurements the changes in the mean square nuclear radii are: delta 2 > (A=144 to 146)=0.266(10) fm 2 , and delta 2 > (A=151 to 152)=0.262(10) fm 2 . These results, together with those of the stable isotopes, show that the average nuclear expansion of samarium can be accounted for by the liquid drop model with deformations. (orig.)

  7. AC susceptibility, XRD and DSC studies of Sm1-xGdxMn2Si2 silicides

    International Nuclear Information System (INIS)

    Kervan, S.; Kilic, A.; Gencer, A.

    2004-01-01

    X-ray powder diffraction, AC susceptibility and differential scanning calorimetry (DSC) studies were performed on the polycrystalline Sm 1-x Gd x Mn 2 Si 2 (0≤x≤1) compounds. All compounds investigated crystallize in the body-centered tetragonal ThCr 2 Si 2 -type structure with the space group I4/mmm. Substitution of Gd for Sm leads to a linear decrease of the lattice constants and the unit cell volume. The lattice constants and the unit cell volume obey Vegard's law. At low temperatures, the rare earth sublattice orders and reconfigures the ordering in the Mn sublattice. The samples with x=0.6 and 0.8 exhibit spin reorientation phenomenon. The Neel temperature T N (Mn) determined by DSC technique and the Curie temperature T C (RE) increase linearly with increasing Gd content x. The results are summarized in the x-T magnetic phase diagram

  8. The Gd-Co-Al system at 870/1070 K as a representative of the rare earth-Co-Al family and new rare-earth cobalt aluminides: Crystal structure and magnetic properties

    Science.gov (United States)

    Morozkin, A. V.; Garshev, A. V.; Knotko, A. V.; Yapaskurt, V. O.; Mozharivskyj, Y.; Yuan, Fang; Yao, Jinlei; Nirmala, R.; Quezado, S.; Malik, S. K.

    2018-05-01

    The Gd-Co-Al system has been investigated at 870/1070 K by X-ray and elemental EDS analyses. The existence of the known compounds Gd2Co3Al9 (Y2Co3Ga9-type), Gd3Co4.5Al11.5 (Gd3Co4.6Al11) (Gd3Ru4Al12-type), Gd3Co6-7.4Al3-1.6 (CeNi3-type), GdCo1.15-0.65Al0.85-1.35 (MgZn2-type), Gd2Co2Al (Mo2NiB2-type) and Gd3Co3.5-3.25Al0.5-0.75 (W3CoB3-type) has been confirmed at 870/1070 K. Structure types have been determined for Gd2Co6Al19 (U2Co6Al19-type), Gd7Co6Al7 (Pr7Co6Al7-type), Gd6Co2-2.21Al1-0.79 (Ho6Co2Ga-type) and Gd14Co3.2Al2.8 (Gd14Co2.58Al3.42 at 970 K) (Lu14Co3In3-type). The structures of Gd6Co2Al, Gd6Co2.21Al0.79 and Gd14Co2.58Al3.42 flux-grown at 970 K have been refined from the single crystal X-ray diffraction data. Additionally, new ternary compounds Gd2Co5.7-5.3Al1.3-1.7 (Er2Co7-type) and Gd58Co20Al22 (unknown type structure) have been identified. Quasi-binary solid solutions were detected for Gd2Co17, GdCo5, Gd2Co7, GdCo3, GdCo2 and GdAl2 at 870/1070 K, while no appreciable solubility was observed for the other binary compounds in the Gd-Co-Al system. Magnetic properties of the Gd2Co3Al9, Gd3Co4.6Al11, Gd7Co6Al7, Gd6Co2.2Al0.8 and Gd14Co2.58Al3.42 compounds have been studied and are presented in this work. Gd6Co2.2Al0.8, Gd3Co4.6Al11, Gd7Co6Al7 and Gd14Co2.58Al3.42 order ferromagnetically, while Gd2Co3Al9 displays antiferromagnetic transition. Additionally, {Y, Sm, Tb - Tm}2Co6Al19 (U2Co6Al19-type), Yb2Co3Al9 (Y2Co3Ga9-type), {Y, Sm, Tm, Yb}3Co4.6Al11 (Gd3Ru4Al12-type) and Tb7Co6Al7 (Pr7Co6Al7-type) compounds have been synthesized and investigated.

  9. Magnetocaloric effect and refrigeration cooling power in amorphous Gd7Ru3 alloys

    OpenAIRE

    Pramod Kumar; Rachana Kumar

    2015-01-01

    In this paper, we report the magnetic, heat capacity and magneto-caloric effect (MCE) of amorphous Gd7Ru3 compound. Both, temperature dependent magnetization and heat capacity data reveals that two transitions at 58 K and 34 K. MCE has been calculated in terms of isothermal entropy change (ΔSM) and adiabatic temperature change (ΔTad) using the heat capacity data in different fields. The maximum values of ΔSM and ΔTad are 21 Jmol−1K−1 and 5 K respectively, for field change of 50 kOe whereas re...

  10. 179Ta and 180Ta structure by transfer reactions

    International Nuclear Information System (INIS)

    Warde, Elias.

    1979-01-01

    Transfer reactions (α,t); ( 3 He,d); (p,t) and (p,d) have been used to study the nuclear spectroscopy of 179 Ta and 180 Ta. In 179 Ta, 5/2 - and 9/2 - states of the 1/2(541) configuration have been identified. The core-quasiproton interaction has to be taken into account in order to explain the two-nucleon transfer intensities in the 181 Ta(p,t) 179 Ta reaction. A level scheme has been proposed for 180 Ta for the first time. Especially the ground state is identified with the (1 + ,1) level of the [7/2 + (404)sub(p), 9/2 + (624)sub(n)] configuration and spin (9 - ,9) of the configuration [9/2 - (514)sub(p), 9/2 + (624)sub(n)] has been assigned to the long-lived isomer. From the observed configurations in 180 Ta, the matrix elements of the effective residual interaction vsub(np) have been deduced and compared to theoretical predictions [fr

  11. Lifetime measurement in 144Gd

    International Nuclear Information System (INIS)

    Jensen, H.J.; Gast, W.; Georgiev, A.; Jaeger, H.M.; Lieder, R.M.; Utzelmann, S.; Gierlik, M.; Morek, T.; Przestrzelska, K.; Rzaca-Urban, T.; Dewald, A.; Kuehn, R.; Meier, C.; Ender, C.; Haertlein, T.

    1996-01-01

    The lifetime measurements of excited states in 144 Gd were carried out using the Koeln RDM-plunger together with the 2 x 3 CLUSTER detector setup in Heidelberg. The nucleus was populated in the 100 Mo( 48 Ti,4n) 144 Gd reaction at a beam energy of 205 MeV giving a recoil velocity of v/c = 2.6 %. Three and higher fold γ-ray coincidences were measured at 12 target-stopper distances ranged from 0 to 400 μm. Both the dipole and quadrupole bands in 144 Gd have been observed. The analysis is in progress

  12. Komatiites of the Onverwacht Group, S. Africa: REE geochemistry, Sm/Nd age and mantle evolution

    Science.gov (United States)

    Jahn, Bor-Ming; Gruau, G.; Glikson, A. Y.

    1982-08-01

    Komatiites of the Tjakastad Subgroup of the Onverwacht Group (S. Africa) were dated by the Sm/Nd method. A whole-rock isochron yields an age of 3.56±0.24 (2 σ) AE, with initial 143Nd/144Nd ratio of 0.50818±23 (2 σ), corresponding to ɛ Nd( T)= + 1.9±4.5. This age is interpreted as the time of initial Onverwacht volcanism. This result agrees with earlier Sm/Nd data of Hamilton et al. (1979) and is consistent with the Rb-Sr result of Jahn and Shih (1974). Komatiites may be divided into 3 groups based on the typology of heavy REE distributions (Jahn and Gruau 1981). According to this scheme, the Onverwacht komatiites of the present study belong to two groups: the predominant Group II rocks showing (Gd/Yb)N≃1.4, CaO/Al2O3 = 1.33, Al2O3/TiO2≃10.6; and the subordinate Group III rocks with (Gd/Yb)Nconnotation of the chemical parameters, such as CaO/Al2O3, (Gd/Yb)N or Al2O3/TiO2 ratio has not been firmly established. The characteristic “high” CaO/Al2O3 or (Gd/Yb)N ratios in many Onverwacht Group rocks can also be explained as a result of local short-term mantle heterogeneity.

  13. The new carbodiimide Li_2Gd_2Sr(CN_2)_5 having a crystal structure related to that of Gd_2(CN_2)_3

    International Nuclear Information System (INIS)

    Unverfehrt, Leonid; Stroebele, Markus; Meyer, H. Juergen

    2013-01-01

    The new carbodiimide compounds Li_2RE_2Sr(CN_2)_5 (RE = Sm, Gd, Eu, Tb) were prepared by a straight forward solid state metathesis reaction of REF_3, SrF_2, and Li_2(CN_2) at around 600 C. The crystal structure of Li_2Gd_2Sr(CN_2)_5 was solved based on X-ray single-crystal diffraction data. Corresponding Li_2RE_2Sr(CN_2)_5 compounds were analyzed by isotypic indexing of their powder patterns. The crystal structure of Li_2Gd_2Sr(CN_2)_5 can be well related to that of Gd_2(CN_2)_3, because both structures are based on layered structures composed of close packed layers of [N=C=N]"2"- sticks, alternating with layers of metal ions. The crystal structure of Li_2Gd_2Sr(CN_2)_5 can be considered to contain an ABC layer sequence of [N = C=N]"2"- layers with the interlayer voids being occupied by (three) distinct types of cations. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Crystallographic and 119Sn and 155Gd Moessbauer analyses of Gd5Ge2(Si1-xSnx)2 (x = 0.23 and x = 0.40)

    International Nuclear Information System (INIS)

    Campoy, J. C. P.; Santos, A. O. dos; Cardoso, L. P.; Paesano, A.; Raposo, M. T.; Fabris, J. D.

    2010-01-01

    We report the structural characterization of Gd 5 Ge 2 (Si 1-x Sn x ) 2 (x = 0.23 and x = 0.40) compounds by means of 100 and 298 K-X-ray diffractometry (XRD) and 4 K- 155 Gd and 298 K- 119 Sn Moessbauer spectroscopy. These compounds order ferromagnetically at 218.4 and 172.7 K, respectively. At ∼100 K, it was identified the Gd 5 Si 4 -orthorhombic phase (type I) for both samples. At ∼298 K, it was identified a Gd 5 Si 2 Ge 2 -monoclinic phase, for x = 0.23 and a Sm 5 Sn 4 -orthorhombic phase (type II), for x 0.40. The Rietveld analysis of XRD data suggests a first order magneto-structural transition at Curie temperature for both compositions. Moessbauer results are well consistent with the proposed crystallographic models for these systems.

  15. Radiation damage in SmS, SmSsub(1-x)Psub(x) and SmB6

    International Nuclear Information System (INIS)

    Morillo, J.; Bordier, G.; de Novion, C.H.; Senateur, J.P.; Jun, J.

    1984-08-01

    Large conductivity increases under 21 K electron or neutron irradiations are observed in SmS and SmSsub(1-x)Psub(x). It is shown that they are related to Sm defects. A possible mechanism is 4f electron delocalization around radiation defects. In SmB 6 , the low temperature resistivity increase desappears under 21 K irradiation. The thermal stability of the defects is also investigated up to room temperature

  16. Standard Missile-6 (SM-6)

    Science.gov (United States)

    2016-12-01

    attack or Anti-Ship Cruise Missiles in flight. The SM-6 ERAM program is an evolutionary, capabilities based acquisition program that will use spiral ...Prior SAR Total O&S Estimates - Dec 2014 SAR 460.3 Programmatic/Planning Factors 0.0 Cost Estimating Methodology 0.0 Cost Data Update 0.0 Labor Rate

  17. EUSO-TA prototype telescope

    Energy Technology Data Exchange (ETDEWEB)

    Bisconti, Francesca, E-mail: francesca.bisconti@kit.edu

    2016-07-11

    EUSO-TA is one of the prototypes developed for the JEM-EUSO project, a space-based large field-of-view telescope to observe the fluorescence light emitted by cosmic ray air showers in the atmosphere. EUSO-TA is a ground-based prototype located at the Telescope Array (TA) site in Utah, USA, where an Electron Light Source and a Central Laser Facility are installed. The purpose of the EUSO-TA project is to calibrate the prototype with the TA fluorescence detector in presence of well-known light sources and cosmic ray air showers. In 2015, the detector started the first measurements and tests using the mentioned light sources have been performed successfully. A first cosmic ray candidate has been observed, as well as stars of different magnitude and color index. Since Silicon Photo-Multipliers (SiPMs) are very promising for fluorescence telescopes of next generation, they are under consideration for the realization of a new prototype of EUSO Photo Detector Module (PDM). The response of this sensor type is under investigation through simulations and laboratory experimentation.

  18. EUSO-TA prototype telescope

    Science.gov (United States)

    Bisconti, Francesca; JEM-EUSO Collaboration

    2016-07-01

    EUSO-TA is one of the prototypes developed for the JEM-EUSO project, a space-based large field-of-view telescope to observe the fluorescence light emitted by cosmic ray air showers in the atmosphere. EUSO-TA is a ground-based prototype located at the Telescope Array (TA) site in Utah, USA, where an Electron Light Source and a Central Laser Facility are installed. The purpose of the EUSO-TA project is to calibrate the prototype with the TA fluorescence detector in presence of well-known light sources and cosmic ray air showers. In 2015, the detector started the first measurements and tests using the mentioned light sources have been performed successfully. A first cosmic ray candidate has been observed, as well as stars of different magnitude and color index. Since Silicon Photo-Multipliers (SiPMs) are very promising for fluorescence telescopes of next generation, they are under consideration for the realization of a new prototype of EUSO Photo Detector Module (PDM). The response of this sensor type is under investigation through simulations and laboratory experimentation.

  19. Investigation of BaMoO4-Ln2(MoO4)3 systems (Ln = Nd, Sm, Yb)

    International Nuclear Information System (INIS)

    Vakulyuk, V.V.; Evdokimov, A.A.; Khomchenko, G.P.

    1982-01-01

    Using the methods of X-ray phase and differential-thermal analyses phase ratios in the systems BaMoO 4 -Ln 2 (MoO 4 ) 3 (Ln=Nd, Sm, Yb); BaNd 2 (MoO 4 ) 4 -MaGd 2 (MoO 4 ) are studied. Unit cell parameters and the character of melting of the compounds BaLn 2 (MoO 4 ) 4 are specified. Effect of growth conditions on laminated nature of BaGd 2 (MoO 4 ) 4 monocrystals is studied

  20. Excited states in 146Sm and 147Sm

    International Nuclear Information System (INIS)

    Kownacki, J.; Sujkowski, Z.; Hammaren, E.; Liukkonen, E.; Piiparinen, M.; Lindblad, Th.; Ryde, H.

    1979-10-01

    The sup(144,146)Nd(α,xn) and sup(146,148)Nd( 3 He,xn) reactions with Esub(α) = 20 - 43 MeV and E 3 sub(He) = 19 - 27 MeV are used to investigate excited states in the isotopes 146 Sm and 147 Sm. The experiments involve measurements of singles γ-ray spectra and conversion electron spectra, γ-ray angular distributions and three parameter (E sub(γ)E sub(γ) time) coincidences. From these experiments information is obtained for states with spin up to I = 13 + and I = 27/2 - , respectively, These states are interpeted within the framework of the cluster-vibration model (CVM) as well as the shell model. (author)

  1. Småhuse: Indretning og funktion

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Sigbrand, Lone; Frandsen, Anne Kathrine

    Denne anvisning omhandler generelle krav og anbefalinger til indretning og funktion af nybyggede småhuse i henhold til bestemmelserne i Bygningsreglement 2010 (BR10). Småhuse - Indretning og funktionSmåhuse omfatter fritliggende og sammenbyggede enfamiliehuse med lodret lejlighedsskel i indtil...

  2. The TA and TALE Experiments

    International Nuclear Information System (INIS)

    Thomson, Gordon

    2006-01-01

    The TA/TALE experiment is under construction, and is being deployed in Millard County, Utah. It will consist of a suite of detectors covering four orders of magnitude in energy, from 10 16.5 to 10 20.5 eV, and will observe cosmic ray showers with fluorescence detectors and arrays of scintillation counters. Events will be seen by multiple detectors and cross calibration of detectors' energy scales will be possible. TA/TALE will observe all three features of the spectrum of ultrahigh energy cosmic rays, observe the galactic/extragalactic transition, study the cosmology of cosmic ray sources, and perform anisotropy studies with unprecedented accuracy

  3. Superconductivity and magnetism in Ir-doped GdFeAsO

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Y.J.; Chen, Y.L. [Key Laboratory of Magnetic Levitation and Maglev Trains (Ministry of Education of China), Superconductivity R and D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Cheng, C.H. [School of Materials Science and Engineering, University of New South Wales, Sydney 2052 NSW (Australia); Yang, Y.; Jiang, J.; Wang, Y.Z.; Zhang, Y. [Key Laboratory of Magnetic Levitation and Maglev Trains (Ministry of Education of China), Superconductivity R and D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Zhao, Y., E-mail: yzhao@swjtu.edu.c [Key Laboratory of Magnetic Levitation and Maglev Trains (Ministry of Education of China), Superconductivity R and D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); School of Materials Science and Engineering, University of New South Wales, Sydney 2052 NSW (Australia)

    2010-11-01

    The 5d-transition metal, Ir has successfully been doped at Fe site and induced superconductivity in GdFeAsO at T{sub c} = 18.9 K and {approx}20 atom%. The Ir-doping shortened the c-axis length and stretched the a-axis one, which led to enhance the coupling between the FeAs- and SmO-layer, and to weaken the bonding between Fe and As atom. Paramagnetism was observed in all of the samples, which was resulted from the magnetic Gd ion as in the F-doped GdFeAsO. An upper critical field of GdFe{sub 0.8}Ir{sub 0.2}AsO was extrapolated to around 24 T, much smaller than that of F-doped GdFeAsO owing to a relatively low T{sub c} and small value of dH{sub c2}/dT.

  4. TA-55 change control manual

    International Nuclear Information System (INIS)

    Blum, T.W.; Selvage, R.D.; Courtney, K.H.

    1997-11-01

    This manual is the guide for initiating change at the Plutonium Facility, which handles the processing of plutonium as well as research on plutonium metallurgy. It describes the change and work control processes employed at TA-55 to ensure that all proposed changes are properly identified, reviewed, approved, implemented, tested, and documented so that operations are maintained within the approved safety envelope. All Laboratory groups, their contractors, and subcontractors doing work at TA-55 follow requirements set forth herein. This manual applies to all new and modified processes and experiments inside the TA-55 Plutonium Facility; general plant project (GPP) and line item funded construction projects at TA-55; temporary and permanent changes that directly or indirectly affect structures, systems, or components (SSCs) as described in the safety analysis, including Facility Control System (FCS) software; and major modifications to procedures. This manual does not apply to maintenance performed on process equipment or facility SSCs or the replacement of SSCs or equipment with documented approved equivalents

  5. Niobium Nb and tantalum Ta

    International Nuclear Information System (INIS)

    Busev, A.I.; Tiptsova, V.G.; Ivanov, V.M.

    1978-01-01

    The basic methods for determining niobium and tantalum in various objects are described. Nb and Ta are separated with the aid of N-benzoyl-N-phenylhydroxylamine by precipitating Nb(5) from a tartaric acid solution with subsequent precipitation of Ta from the filtrate. The gravimetric determination of Nb and Ta in steels is based on their quantitative separation from a diluted solution by way of hydrolysis with subsequent after-precipitation with phenylarsonic acid (in the absence of W). The gravimetric determination of Nb in the presence of W is carried out with the aid of Cupferron. To determine Nb in its carbide, Nb(5) reduced to Nb(3) is titrated with a solution of K 2 Cr 2 O 7 in the presence of phenyl-anthranilic acid. The photometric determination of Nb in tungsten-containing steels and in ores containing Ti, W, Mo and Cr is based on the rhodanide method. Nb is determined in alloys with Zr and Ti photometrically with the aid of 4-(2-pyridylazo)-resorcin and in alloyed steels with the aid of benzhydroxamic acid. The latter complex is extracted with chloroform. This method is used to determine Nb in rocks. The photometric determination of Ta in TiCl 4 is carried out with the aid of pyrogallol, in commercial niobium with the aid of methyl violet, and in steel with the aid of 4-(-pyridylazo)-resorcin. Also described is the polarographic determination of Nb in tantalum pentoxide

  6. Institutional Interpretation of Participatory TA

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Øjvind

    2014-01-01

    . The aim of the article is thus to relate the challenges of establishing and continuing pTA as a societal practice to the question of societal institutions and their logics. Towards this aim, the paper draws on a number of different theoretical directions within New Institutionalism and attempts to build...

  7. Applied strain dependence of critical current and internal lattice strain for BaHfO_3-doped GdBa_2Cu_3O_y coated conductors

    International Nuclear Information System (INIS)

    Usami, Takashi; Yoshida, Yutaka; Ichino, Yusuke; Sugano, Michinaka; Machiya, Shutaro; Ibi, Akira; Izumi, Teruo

    2016-01-01

    The strain effect of REBa_2Cu_3O_y (REBCO: RE = Y, Gd, Sm)-coated conductors (CCs) on critical current (I_c) is one of the most fundamental factors for superconducting coil applications. In this study, we aim to clarify the effect of artificial pinning center shapes on the strain effect in BHO-doped GdBCO CCs. To achieve this, we fabricated a Pure-GdBCO CC, a BHO nanorod-doped GdBCO CC and a multilayered-GdBCO (ML-GdBCO) CC, and carried out bending tests. As the result, the strain dependence of I_c for each CC showed an upward convex and the peak strain of the BHO-doped GdBCO CC shifts towards the compressive strain independent of the BHO shapes. In addition, the strain sensitivity of I_c in the GdBCO CCs including BHO becomes smaller. To clarify the difference between the strain sensitivity of I_c and the peak strain among the CCs, we evaluated the residual strain and the slopes of the internal lattice strains against the applied tensile strain (β). From this measurement, the residual strains for the Pure-GdBCO CC and the ML-GdBCO CC were almost the same. In addition, there was no change in the β value between the Pure-GdBCO and ML-GdBCO CCs. These results suggest that the changes in peak strain and strain sensitivity were not related to the internal lattice strain. (author)

  8. Implantation sites of Ce and Gd in diamond

    CERN Document Server

    Bharuth-Ram, K; Hofsäss, H C; Ronning, C; Dietrich, M

    2002-01-01

    The implantation sites of rare earth (RE) probes /sup 141/Ce (t/sub 1 /2/=32 d) and /sup 149/Gd (t/sub 1/2/=9.28 d) in diamond have been investigated using the emission channeling (EC) technique. Parent isotopes /sup 141/Cs and /sup 149/Dy were implanted into type IIa, diamond samples at an energy of 60 keV at the online isotope separator ISOLDE at CERN. /sup 141/Cs decays through the chain /sup 141/Cs-/sup 141/Ba-/sup 141/La-/sup 141/Ce-/sup 141/ Pr. EC measurements were made on the 102 keV conversion electrons emitted in the decay of /sup 141/Pr to its ground state. The decay of /sup 149 /Dy follows the chain /sup 149/Dy-/sup 149/Tb-/sup 149/Gd-/sup 149 /Eu-/sup 149/Sm. EC measurements were made on the 101 keV electrons emitted in the decay of /sup 149/Eu. Two-dimensional channeling patterns of the conversion electrons were obtained along and axial directions by raster scans with a Si surface barrier detector. Comparison of the observed patterns with simulated spectra show that in diamond 45-50% of the RE...

  9. Temperature effects on separation of Gd3+ from Gd-DTPA-folate using nanofiltration method

    Science.gov (United States)

    Rahayu, I.; Indraneli, R. P.; Yuliyati, Y. B.; Anggraeni, A.; Soedjanaatmadja, U. M. S.; Bahti, H. H.

    2018-05-01

    MRI is one of the best techniques in medical diagnostics. Contrast agents are used to improve the visual of organs that are difficult to distinguish through MRI. Gd-DTPA-folate is one of the specific contrast agents against cancer diagnosis, because it has a high affinity to folate receptors. In the complexing Gd-DTPA-folate, does not rule out the complexity step runs imperfectly, so there is still Gd3+ in the Gd-DTPA-folate complex. The separation of Gd3+ from the Gd-DTPA-folate complex is important to eliminate toxic effects on the contrast agent. This study aims to determine the effect of temperature on the separation of Gd-DTPA-folate from Gd3+ with nanofiltration. The method are preparation Gd-DTPA-folate from GdCl3.6H2O and DTPA-folate by reflux method, then separated Gd-DTPA-folate complex from Gd3+ with nanofiltration at variation temperature (40, 41, 42, 43, 44oC ). Then, the values of flux and rejection coefficients were analyzed. The results showed that the optimum temperature for the separation of Gd3+ from Gd-DTPA-folate was achieved at 42.6°C with the rejection coefficient of 24% and the permeate flux of 403 L.m-2.h-1.

  10. Sierra/SM theory manual.

    Energy Technology Data Exchange (ETDEWEB)

    Crane, Nathan Karl

    2013-07-01

    Presented in this document are the theoretical aspects of capabilities contained in the Sierra/SM code. This manuscript serves as an ideal starting point for understanding the theoretical foundations of the code. For a comprehensive study of these capabilities, the reader is encouraged to explore the many references to scientific articles and textbooks contained in this manual. It is important to point out that some capabilities are still in development and may not be presented in this document. Further updates to this manuscript will be made as these capabilites come closer to production level.

  11. Rotational structures in 174Ta

    International Nuclear Information System (INIS)

    Hojman, Daniel; Kreiner, A.J.; Davidson, Miguel

    1989-01-01

    The nucleus 174 Ta has been studied for the first time through the fusion-evaporation reaction 169 Tm ( 9 Be,4n) using a 4 mg/cm 2 self-supporting Tm foil in the 40 to 65 MeV bombarding energy range (the 4n channel was found to peak at 50 MeV). The experiments comprised γ and X-ray singles in beam and activity spectra, γ-γ-t coincidences (one of the counters was Compton suppressed) and γ-ray angular distributions. The results obtained allowed the construction of a high-spin level scheme. This scheme, which resembles that of 172 Ta, comprises several rotational bands which correspond to different couplings of the valence nucleons. One of these structures, the doubly decoupled band (DDB), is particularly interesting because it is the first observed case of a DDB based on an I π =3 + state. (Author) [es

  12. Adherence problem for carbon films of up to 0.5 mg/cm2 on vacuum-deposited thick ferromagnetic Gd targets

    International Nuclear Information System (INIS)

    Maier-Komor, P.; Kruecken, R.; Speidel, K.-H.; Kenn, O.

    2004-01-01

    For high precision measurements of magnetic moments and reduced transition probabilities by the combined technique of projectile Coulomb excitation in inverse kinematics and transient magnetic fields sandwich targets of carbon and gadolinium were required. First preparations revealed a lack of adhesion between the Gd film and the vacuum-deposited C layer. Either the adhesion was generally poor or good results could not be reproduced. Now on a 4 mg/cm 2 Gd target 0.5 mg/cm 2 of nat C should be deposited. The Gd was deposited on 1-1.6 mg/cm 2 Ta backings and Cu films of 3.5-7 mg/cm 2 were deposited on the reverse side of the Ta backings. The adhesive properties of evaporated carbon on ferromagnetic gadolinium were investigated. For this either substrate cooling or the deposition of a 5 μg/cm 2 Ti film as adhesion agent were applied

  13. Gd3+-ESR and magnetic susceptibility of GdCu4Al8 and GdMn4Al8

    International Nuclear Information System (INIS)

    Coldea, R.; Coldea, M.; Pop, I.

    1994-01-01

    Gd ESR of GdCu 4 Al 8 and GdMn 4 Al 8 and magnetic susceptibility of GdCu 4 Al 8 , GdMn 4 Al 8 , and YMn 4 Al 8 were measured in the temperature range of 290K--460K and 90K--1050K, respectively. The occurrence of the Mn moment in YMn 4 Al 8 and GdMn 4 Al 8 is strongly correlated with the critical value of d∼2.6 angstrom of the Mn-Mn distance below which the Mn moment is not stable. The experimental data for GdMn 4 Al 8 , compared with the data for the isostructural compounds GdCu 4 Al 8 and YMn 4 Al 8 , show that near the critical value of d, the existence of Mn moment depends not only on the value of d, but also on the local magnetic surroundings. It has been revealed that the magnetic character of Mn moment in YMn 4 Al 8 and GdMn 4 Al 8 changes from an itinerant electron type to a local-moment type with increasing temperature

  14. Solid-state amorphization of SmFe{sub 3} by hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, K.H.; Kubis, M.; Handstein, A.; Gutfleisch, O.

    2000-05-10

    Hydrogen-induced amorphization (HIA) has received much attention as a method for the preparation of amorphous compounds since its discovery by Yeh et al. Meanwhile it has been observed for a large number of intermetallic compounds with C15, C23, B8{sub 2}, DO{sub 19} and L1{sub 2} structures. E.G. the C15 Laves-type compounds (MgCu{sub 2}-type structure) of rare earth (R) - transition metal (T) compounds RT{sub 2} show HIA for R = Y, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho and Er. Aoki et al. postulated that new amorphizing compounds can be expected at high hydrogen pressures. In this work, the structural changes of SmFe{sub 3} (PuNi{sub 3}-type structure) during heating in high hydrogen pressures are reported.

  15. Solid-state amorphization of SmFe3 by hydrogenation

    International Nuclear Information System (INIS)

    Mueller, K.H.; Kubis, M.; Handstein, A.; Gutfleisch, O.

    2000-01-01

    Hydrogen-induced amorphization (HIA) has received much attention as a method for the preparation of amorphous compounds since its discovery by Yeh et al. Meanwhile it has been observed for a large number of intermetallic compounds with C15, C23, B8 2 , DO 19 and L1 2 structures. E.G. the C15 Laves-type compounds (MgCu 2 -type structure) of rare earth (R) - transition metal (T) compounds RT 2 show HIA for R = Y, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho and Er. Aoki et al. postulated that new amorphizing compounds can be expected at high hydrogen pressures. In this work, the structural changes of SmFe 3 (PuNi 3 -type structure) during heating in high hydrogen pressures are reported

  16. GD 358 - the demise of rotational splitting?

    International Nuclear Information System (INIS)

    Hill, J.A.

    1987-01-01

    Observations of GD 358 were obtained at the McDonald Observatory in 1982 and 1985 in order to determine its periods, stability, and rates of period change. The period structure could not be resolved, and the results indicate that GD 358 does not fit the rotational splitting model. It is suggested that if the changes in the amplitude spectra of GD 358 are due to beating of stable modes, then the number of modes must be large. 7 references

  17. Distinguishing a SM-like MSSM Higgs boson from SM Higgs boson ...

    Indian Academy of Sciences (India)

    We explore the possibility of distinguishing the SM-like MSSM Higgs boson from the SM Higgs boson via Higgs boson pair production at future muon collider. We study the behavior of the production cross-section in SM and MSSM with Higgs boson mass for various MSSM parameters tan and A. We observe that at fixed ...

  18. Radiation characteristics of GD-2 fuel

    International Nuclear Information System (INIS)

    Chrapciak, V.

    2008-01-01

    The assembly WWER-440 type Gd-2 has radial profile of enrichment and has 6 pins with Gd 2 O 3 . The maximal enrichment is 4.4%. Some analyses are done for assembly with flat enrichment (4.4%) and without Gd 2 O 3 . In this article are compared some characteristics (decay heat, some nuclide concentration, photon and gamma sources) for real Gd-2 assembly and for flat 4.4% assembly. The TRITON module (in SCALE 5.1) was used. (Author)

  19. Method of quantitative x-ray diffractometric analysis of Ta-Ta2C system

    International Nuclear Information System (INIS)

    Gavrish, A.A.; Glazunov, M.P.; Korolev, Yu.M.; Spitsyn, V.I.; Fedoseev, G.K.

    1976-01-01

    The syste86 Ta-Ta 2 C has beemonsidered because of specific features of diffraction patterns of the components, namely, overlapping of the most intensive reflexes of both phases. The method of standard binary system has been used for quantitative analysis. Because of overlapping of the intensive reflexes dsub(1/01)=2.36(Ta 2 C) and dsub(110)=2.33(Ta), the other, most intensive, reflexes have been used for quantitative determination of Ta 2 C and Ta: dsub(103)=1.404 A for tantalum subcarbide and dsub(211)=1.35A for tantalum. Besides, the TaTa 2 C phases have been determined quantitatively with the use of another pair of reflexes: dsub(102)=1.82 A for Ta 2 C and dsub(200)=1.65 A for tantalum. The agreement between the results obtained while performing the quantitative phase analysis is good. To increase reliability and accuracy of the quantitative determination of Ta and Ta 2 C, it is expedient to carry out the analysis with the use of two above-mentioned pairs of reflexes located in different regions of the diffraction spectrum. Thus, the procedure of quantitative analysis of Ta and Ta 2 C in different ratios has been developed taking into account the specific features of the diffraction patterns of these components as well as the ability of Ta 2 C to texture in the process of preparation

  20. Identification of 162Gd and a new type of identical bands

    International Nuclear Information System (INIS)

    Jones, E. F.; Gore, P. M.; Hamilton, J. H.; Ramayya, A. V.; Dodder, R. S.; Beyer, C. J.; Hwang, J. K.; Zhang, X. Q.; Kormicki, J.; Zhu, S. J.; Lima, A. P. de; Cole, J. D.; Aryaeinejad, R.; Ma, W. C.; Ter-Akopian, G. M.; Daniel, A. V.; Oganessian, Yu. Ts.; Rasmussen, J. O.; Asztalos, S. J.; Lee, I. Y.

    1998-01-01

    From γ-γ-γ coincidence measurements in spontaneous fission of 252 Cf, level energies were established to spins 14 + to 20 + in many neutron-rich nuclei. New isotope 162 Gd was identified. Yrast bands of 152,154,156 Nd, 156,158,160 Sm, and 160,162 Gd exhibit near-identical transition energies and moments of inertia (MOI) shifted by the same constant amounts for every spin state from 2 + to 12 + or 14 + for nuclei differing by 2n, 4n, 2p, 4p, α, α+2p, and α+2n. These shifted identical bands (SIB) are a new phenomenon. Analysis of all known even-even proton- to neutron-rich nuclei from Ba(Z=56) to Os(Z=76) reveal no SIB for proton-rich nuclei and few cases of SIB for the most neutron-rich pairs around N=98-102 separated by 2n and 2p

  1. Recent experiments at Brookhaven: level structure of N = 86 isotones 156Yb and 150Gd

    International Nuclear Information System (INIS)

    Sunyar, A.W.

    1980-01-01

    States of the N = 86 isotones 156 Yb and 150 Gd have been studied by means of the 144 Sm( 16 O,4n) 156 Yb, 113 In( 46 Ti,p2n) 156 Yb, and 124 Sn( 30 Si,4n) 150 Gd reactions. Levels have been established to spin 36 h-bar and over 12.5 MeV in excitation in 150 Gd and to beyond spin 25 h-bar in 156 Yb. The systematics of levels in the N = 86 isotones from 150 Gd to 156 Yb are described, and the near-spherical shell model description for states in this region to near spin 30 h-bar is discussed. A T/sub 1/2/ = 6 ns, 72-keV isomeric transition in 156 Yb has been discovered, and an E1 multipolarity is assigned to this transition. The spin-parity of the isomeric state is established as 11 - . 6 figures

  2. checkCIF/PLATON report Datablock: Sm

    Indian Academy of Sciences (India)

    Moiety formula C59 H45 N2 O6 Sm. Sm (C14 H12 N2) ... 4.0 Ratio. PLAT234_ALERT_4_C Large Hirshfeld Difference O4 -- C24 .. 0.16 Ang. ... outliers and unusual parameters, but every test has its limitations and alerts that are not important.

  3. Copper diffusion in TaN-based thin layers

    Energy Technology Data Exchange (ETDEWEB)

    Nazon, J. [Universite Montpellier II, Institut Charles Gerhardt, UMR 5253 CNRS-UM2-ENSCM-UM1, cc 1504, 34095 Montpellier Cedex 5 (France); Fraisse, B. [Laboratoire Structure, Proprietes et Modelisation des Solides (UMR 8580), Ecole Centrale de Paris, Grande Voie des Vignes, 92295 Chatenay-Malabry Cedex (France); Sarradin, J. [Universite Montpellier II, Institut Charles Gerhardt, UMR 5253 CNRS-UM2-ENSCM-UM1, cc 1504, 34095 Montpellier Cedex 5 (France); Fries, S.G. [SGF Scientific Consultancy, Arndt str.9, D-52064 Aachen (Germany); Tedenac, J.C. [Universite Montpellier II, Institut Charles Gerhardt, UMR 5253 CNRS-UM2-ENSCM-UM1, cc 1504, 34095 Montpellier Cedex 5 (France); Frety, N. [Universite Montpellier II, Institut Charles Gerhardt, UMR 5253 CNRS-UM2-ENSCM-UM1, cc 1504, 34095 Montpellier Cedex 5 (France)], E-mail: Nicole.Frety@univ-montp2.fr

    2008-07-15

    The diffusion of Cu through TaN-based thin layers into a Si substrate has been studied. The barrier efficiency of TaN/Ta/TaN multilayers of 150 nm in thickness has been investigated and is compared with that of TaN single layers. Thermal stabilities of these TaN-based thin layers against Cu diffusion were determined from in situ X-ray diffraction experiments, conducted in the temperature range of 773-973 K. The TaN/Ta/TaN barrier appeared to be more efficient in preventing Cu diffusion than the TaN single layer.

  4. Evaluation of Radioisotope Production Process of 153Sm and 153Sm-EDTMP Radiopharmaceuticals

    International Nuclear Information System (INIS)

    Kadarisman; Sri Hastini; Yayan Tahyan; Abidin; Dadang Hafid; Enny Lestari

    2007-01-01

    Experiments on the process of 153 Sm radioisotope and labeling of 153 Sm-EDTMP radiopharmaceuticals were carried out. This experiments included preparation of Sm 2 O 3 target, dissolution of post irradiation, determination of radioactivity concentration of 153 Sm radioisotope, radionuclide purity, EDTMP labeling, determination of radiochemical purity and pH. In these experiments the total radioactivity 153 Sm product is round about 2845.83 mCi to 36963.31 mCi, or with the radioactivity concentration between 474 mCi/ml to 6160.55 mCi/ml in the SmCl 3 solution form, each its volume is 6.0 ml, and the samarium content is 5.76 mg/ml, and the radionuclide purity of 153 Sm is 100 %. All of the 153 Sm- EDTMP radiopharmaceuticals product are fulfilled requirements the radioactivity concentration, Sm content, radiochemical purity and pH. The radioactivity concentration of 153 Sm-EDTMP radiopharmaceuticals is 37.50 mCi/ml (minimum) to 283.50 mCi/ml (highest). The pH 7.5 were 8 products, and the rest are pH 8.5. Radiochemical purity of 153 Sm-EDTMP are round about 90.00 % to 99.44 %. (author)

  5. Distinguishing a SM-like MSSM Higgs boson from SM Higgs boson at muon collider

    International Nuclear Information System (INIS)

    Singhal, Jai Kumar; Singh, Sardar; Nagawat, Ashok K.

    2007-01-01

    We explore the possibility of distinguishing the SM-like MSSM Higgs boson from the SM Higgs boson via Higgs boson pair production at future muon collider. We study the behavior of the production cross-section in SM and MSSM with Higgs boson mass for various MSSM parameters tanβ and m A . We observe that at fixed CM energy, in the SM, the total cross-section increases with the increase in Higgs boson mass whereas this trend is reversed for the MSSM. The changes that occur for the MSSM in comparison to the SM predictions are quantified in terms of the relative percentage deviation in cross-section. The observed deviations in cross-section for different choices of Higgs boson masses suggest that the measurements of the cross-section could possibly distinguish the SM-like MSSM Higgs boson from the SM Higgs boson. (author)

  6. Corrosion Characteristics of Ti-xTa Alloys with Ta contents

    International Nuclear Information System (INIS)

    Kim, H. J.; Choe, H. C.

    2013-01-01

    The purpose of this study was to investigate corrosion characteristics of Ti-xTa alloys with Ta contents. Ti-xTa alloys used as samples (x=30, 40%) were arc-melted under argon atmosphere of 99.9% purity. Ti-xTa alloys were homogenized for 12hr at 1000 .deg. C and then water quenched. The surface characteristics of Ti-xTa alloys were investigated using optical microscopy (OM) and X-ray diffractometer (XRD). The anodic corrosion behaviors of the specimens were examined through potentiodynamic, potentiostatic and galvanostatic test in 0.9 % NaCl solution at 36.5 ± 1 .deg. C. After corrosion test, the surface characteristics of Ti-xTa alloys were investigated using OM. The microstructure of Ti-Ta alloy showed the beta structure with Ta content. The corrosion resistance of Ti alloy was improved by increasing Ta content and the corrosion morphology of Ti-Ta alloy showed that the site attacked by chloride ion decreased from the active to passive region with Ta content. Potential of Ti-40Ta alloy increased as time increased, whereas, current density of Ti-40Ta alloy decreased as time increased compared to Ti-30 alloy

  7. Favored neutron excitations in superdeformed Gd-147

    NARCIS (Netherlands)

    Theisen, C; Khadiri, N; Vivien, JP; Ragnarsson, J; Beausang, CW; Beck, FA; Belier, G; Byrski, T; Curien, D; deFrance, G; Disdier, D; Duchene, G; Finck, C; Flibotte, S; Gall, B; Haas, B; Hanine, H; Herskind, B; Kharraja, B; Merdinger, JC; Nourreddine, A; Nyako, BM; Perez, GE; Prevost, D; Stezowski, O; Rauch, I; Rigollet, C; Savajols, H; SharpeySchafer, J; Twin, PJ; Wei, L; Zuber, K

    1996-01-01

    Four new superdeformed (SD) bands have been observed in Gd-147 using the EUROGAM II spectrometer. By comparison with (146,148,149),Gd SD bands, we use the effective alignment to assign excited band configurations, with the support of the Nilsson-Strutinsky cranking formalism. The effect of the

  8. Investigation of Gd compounds using synchrotron radiation

    International Nuclear Information System (INIS)

    Tyszka, B.; Szade, J.; Burian, W.; Skorek, G.; Deniszczyk, J.; Sikora, M.; Zajac, D.; Kapusta, Cz.; Matteucci, M.; Bondino, F.; Zacchigna, M.; Zangrando, M.

    2005-01-01

    The electronic structure of ferromagnetic compound GdTiGe has been investigated using element sensitive methods-X-ray absorption spectroscopy (XAS), X-ray magnetic circular dichroism (XMCD) and resonant inelastic X-ray scattering (RIXS). Additionally, another ferromagnet GdTiSi has been studied using XMCD. XMCD revealed a strong dichroic signal at Gd L 2 and L 3 edges, which can be related to polarisation of Gd 5d band. XAS at Ti L 2,3 edges has exhibited a structure which appeared to be in general agreement with the LAPW calculations. RIXS spectra have shown some resonance features for photon energies close to Ti L 2 and Gd M 5 edges

  9. Magnetism at the V/Gd interface

    International Nuclear Information System (INIS)

    Mouketo, L; M'Passi-Mabiala, B; Binggeli, N

    2010-01-01

    Recent experimental investigations into the magnetic properties of V/Gd bilayers have shown that vanadium, which is nonmagnetic in the bulk, can acquire a magnetic moment in such systems. We have performed ab initio pseudopotential calculations to examine the magnetic behavior of V(110)/Gd(0001) bilayers for V layers with thicknesses up to 4 monolayers (ML). We considered both abrupt and atomic intermixed V/Gd interfaces. In both cases, the magnetic moment of the V layer is found to align antiparallel to the moment of the Gd layer, consistent with the experimental observation. However, the magnitude of the V moment at the abrupt interface is considerably smaller than the moments reported experimentally. In the presence of atomic intermixing, instead, substantially larger V moments are found, closer to the experimentally reported moments. On the basis of the calculated atomic and spin resolved density of states, we discuss the possible mechanism responsible for the observed Gd-V antiferromagnetic coupling.

  10. Peculiarities of component interaction in {Gd, Er}-V-Sn Ternary systems at 870 K and crystal structure of RV6Sn6 stannides

    International Nuclear Information System (INIS)

    Romaka, L.; Stadnyk, Yu.; Romaka, V.V.; Demchenko, P.; Stadnyshyn, M.; Konyk, M.

    2011-01-01

    Highlights: → {Gd, Er}-V-Sn ternary systems at 870 K are characterized by formation of stannides with general compositions RV 6 Sn 6 . → Isostructural RV 6 Sn 6 compounds were also found with Y, Dy, Ho, Tm, and Lu. → The crystal structure of RV 6 Sn 6 compounds was determined by powder diffraction method. → Structural analysis showed that RV 6 Sn 6 compounds (R = Gd, Dy-Tm, Lu) are disordered; YV 6 Sn 6 is characterized by structure ordering. - Abstract: The phase equilibria in the Gd-V-Sn and Er-V-Sn ternary systems were studied at 870 K by means of X-ray and metallographic analyses in the whole concentration range. Both Gd-V-Sn and Er-V-Sn systems are characterized by formation of one ternary compound at investigated temperature, with stoichiometry RV 6 Sn 6 (SmMn 6 Sn 6 -type, space group P6/mmm, a = 0.55322(3) nm, c = 0.91949(7) nm for Gd, a = 0.55191(2) nm, c = 0.91869(8) nm for Er). Solubility of the third component in the binary compounds was not observed. Compounds with the SmMn 6 Sn 6 -type were also found with Dy, Ho, Tm, and Lu, while YV 6 Sn 6 compound crystallizes in HfFe 6 Ge 6 structure type. All investigated compounds are the first ternary stannides with rare earth elements and vanadium.

  11. SM-1 negative ion source

    International Nuclear Information System (INIS)

    Huang Zhenjun; Wang Jianzhen

    1987-01-01

    The working principle and characteristics of SM-1 Negative Ion Source is mainly introduced. In the instrument, there is a device to remove O 3 . This instrument can keep high density of negative ions which is generated by the electrical coronas setting out electricity at negative high voltage and can remove the O 3 component which is harmful to the human body. The density of negative ions is higher than 2.5 x 10 6 p./cm 3 while that of O 3 components is less than 1 ppb at the distance of 50 cm from the panel of the instrument. The instrument sprays negative ions automatically without the help of electric fan, so it works noiselessly. It is widely used in national defence, industry, agriculture, forestry, stock raising, sidelines and in the places with an equipment of low density of negative ion or high concentration of O 3 components. Besides, the instrument may also be used to treat diseases, to prevent against rot, to arrest bacteria, to purify air and so on

  12. TA-55 and Sigma Overview

    Energy Technology Data Exchange (ETDEWEB)

    Spearing, Dane Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Safeguards Science and Technology Group (NEN-1)

    2016-11-29

    These are slides from a facility overview presentation for visiting agencies to Los Alamos National Laboratory (LANL). The TA-55 Plutonium Facility (PF-4) is discussed in detail. PF-4 is a unique resource for US plutonium programs. The basic design is flexible and has adapted to changing national needs. It is a robust facility with strong safety and security implementation. It supports a variety of national programs. It will continue for many years into the future. Sigma is then discussed in detail, which handles everything from hydrogen to uranium. It has been in long term service to the Nation (nearly 60 years). It has a flexible authorization basis to handle almost the entire periodic table. It has a wide breadth of prototyping and characterization capabilities. It has integrated program and line management.

  13. Wobbling mode in 167Ta

    International Nuclear Information System (INIS)

    Hartley, D. J.; Ludington, A.; Pifer, R.; Seyfried, E. P.; Vanhoy, J. R.; Janssens, R. V. F.; Carpenter, M. P.; Lauritsen, T.; McCutchan, E. A.; Zhu, S.; Riedinger, L. L.; Darby, I. G.; Riley, M. A.; Aguilar, A.; Wang, X.; Chiara, C. J.; Chowdhury, P.; Lakshmi, S.; Tandel, S. K.; Tandel, U.

    2009-01-01

    The collective wobbling mode, the strongest signature for the rotation of a triaxial nucleus, has previously been seen only in a few Lu isotopes in spite of extensive searches in nearby isotopes. A sequence of transitions in the N=94 167 Ta nucleus exhibiting features similar to those attributed to the wobbling bands in the Lu nuclei has now been found. This band feeds into the πi 13/2 band at a relative energy similar to that seen in the established wobbling bands and its dynamic moment of inertia and alignment properties are nearly identical to the i 13/2 structure over a significant frequency range. Given these characteristics, it is likely that the wobbling mode has been observed for the first time in a nucleus other than Lu, making this collective motion a more general phenomenon.

  14. Sm isotope composition and Sm/Eu ratio determination in an irradiated 153Eu sample by ion exchange chromatography-quadrupole inductively coupled plasma mass spectrometry combined with double spike isotope dilution technique

    International Nuclear Information System (INIS)

    Bourgeois, M.; Isnard, H.; Gourgiotis, A.; Stadelmann, G.; Gautier, C.; Mialle, S.; Nonell, A.; Chartier, F.

    2011-01-01

    Within the framework of the research undertaken by the French Atomic Energy Commission on transmutation of long-lived radionuclides, targets of highly enriched actinides and fission products were irradiated in the fast neutron reactor Phenix. Precise and accurate measurements of the isotopic and elemental composition of the enriched elements are therefore required. In order to obtain the uncertainties of several per mil and to reduce handling time and exposure to analyst on radioactive material, the on-line coupling of ion exchange chromatography with quadrupole inductively coupled plasma mass spectrometry has been associated with the technique of the double spike isotope dilution. We present in this paper the results obtained on an irradiated sample of Europium oxide powder (enriched at 99.13% in 153 Eu). After irradiation of around 5 mg of Eu 2 O 3 powder the theoretical calculations predict the formation of several micrograms of gadolinium and samarium isotopes. In relation to the very high activity of the sample after irradiation and the very low quantity of Sm formed, the on-line ion exchange chromatography separation of Gd, Sm and Eu before Sm isotope ratio measurements has been developed for the quantification of the 152 Sm/ 153 Eu ratio. These on-line measurements were associated with the double spike isotope dilution technique after calibration of a 147 Sm/ 151 Eu spike solution. The external reproducibility of Sm isotopic ratios was determined to be around 0.5% (2 σ) resulting in a final uncertainty on the 152 Sm/ 153 Eu ratio of around 1% (2 σ). These on-line measurements present therefore a robust and high-throughput alternative to the thermal-ionisation mass spectrometry technique used so far in combination with off-line chromatographic separation, particularly in nuclear applications where characterisation of high activity sample solutions is required. (authors)

  15. NMR measurements in milled GdCo2 and GdFe2 intermetallic compounds

    International Nuclear Information System (INIS)

    Tribuzy, C.V.B.; Guimaraes, A.P.; Biondo, A.; Larica, C.; Alves, K.M.B.

    1998-12-01

    We have used the nuclear magnetic resonance technique to study the magnetic and structural properties of the Gd-Co and Gd-Fe metallic systems, starting with the C15 laves phase intermetallic compounds, and submitting them to a high energy milling process. This leads to the amorphization of the samples, as determined by the X-ray diffraction spectra. For the Gd-Co system the NMR study used the 59 Co nucleus; in the Gd-Fe system, 155,157 Gd and 57 Fe were used. Both systems showed segregation of the pure elements, after a few hours of milling. In the Gd-Co system, a single line, of increasing width, was observed in the 59 Co spectrum. In the Gd-Fe system, the 155 Gd and 157 Gd resonances show three lines, arising from electrical quadrupole interaction. With increasing milling time, the lines broaden, and extra lines appear attributed to a cubic phase of Gd; this interpretation is supported by the X-ray analysis of the samples. The 57 Fe NMR spectrum of this system also informs on the direction of magnetization of the samples in the early stages of milling. From 1 h to 7 h of milling, a spectrum of α-Fe was observed. The study of the NMR line intensity as a function of radio frequency (r.f.) power in Gd Co 2 suggests the existence of regions of the samples with different degrees of disorder. We have observed the persistence of NMR signals from the original intermetallic compounds in the samples with up to 10 h and 7 h of milling, respectively, for Gd Co 2 and Gd Fe 2 . (author)

  16. Site preference of metal atoms in Gd_5_-_xM_xTt_4 (M = Zr, Hf; Tt = Si, Ge)

    International Nuclear Information System (INIS)

    Yao, Jinlei; Mozharivskyj, Yurij

    2011-01-01

    Zirconium and hafnium were incorporated into the Gd_5Ge_4 and Gd_5Si_4 parent compounds in order to study the metal-site occupation in the M_5X_4 magnetocaloric phases (M = metals; X = p elements) family. The Gd_5_-_xZr_xGe_4 phases adopt the orthorhombic Sm_5Ge_4-type (space group Pnma) structure for x ≤ 1.49 and the tetragonal Zr_5Si_4-type (P4_12_12) structure for x ≥ 1.77. The Gd_5_-_xHf_xSi_4 compounds crystallize in the orthorhombic Gd_5Si_4-type (Pnma) structure for x ≤ 0.41 and the Zr_5Si_4-type structure for x ≥ 0.7. In both systems, single-crystal X-ray diffraction reveals that the Zr/Hf atoms preferentially occupy the slab-surface M2 and slab-center M3 sites, both of which have a significantly larger Zr/Hf population than the slab-surface M1 site. The metal-site preference, i.e. the coloring problem on the three metal sites, is discussed considering geometric and electronic effects of the local coordination environments. The analysis of the metal-site occupation in Gd_5_-_xZr_xGe_4 and Gd_5_-_xHf_xSi_4 as well as other metal-substituted M_5X_4 systems suggests that both geometric and electronic effects can be used to explain the metal-site occupation. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Electrochemical properties of composite cathodes using Sm doped layered perovskite for intermediate temperature-operating solid oxide fuel cell

    Science.gov (United States)

    Baek, Seung-Wook; Azad, Abul K.; Irvine, John T. S.; Choi, Won Seok; Kang, Hyunil; Kim, Jung Hyun

    2018-02-01

    SmBaCo2O5+d (SBCO) showed the lowest observed Area Specific Resistance (ASR) value in the LnBaCo2O5+d (Ln: Pr, Nd, Sm, and Gd) oxide system for the overall temperature ranges tested. The ASR of a composite cathode (mixture of SBCO and Ce0.9Gd0.1O2-d) on a Ce0.9Gd0.1O2-d (CGO91) electrolyte decreased with respect to the CGO91 content; the percolation limit was also achieved for a 50 wt% SBCO and 50 wt% CGO91 (SBCO50) composite cathode. The ASRs of SBCO50 on the dense CGO91 electrolyte in the overall temperature range of 500-750 °C were relatively lower than those of SBCO50 on the CGO91 coated dense 8 mol% yttria-stabilized zirconia (8YSZ) electrolyte for the same temperature range. From 750 °C and for all higher temperatures tested, however, the ASRs of SBCO50 on the CGO91 coated dense 8YSZ electrolyte were lower than those of the CGO91 electrolyte. The maximum power densities of SBCO50 on the Ni-8YSZ/8YSZ/CGO91 buffer layer were 1.034 W cm-2 and 0.611 W cm-2 at 800 °C and 700 °C.

  18. Observation of dipole bands in 144Sm

    International Nuclear Information System (INIS)

    Raut, R.; Ganguly, S.; Kshetri, R.; Banerjee, P.; Bhattacharya, S.; Dasmahapatra, B.; Mukherjee, A.; Sahasarkar, M.; Goswami, A.; Basu, S.K.; Bhattacharjee, T.; Mukherjee, G.; Chakraborty, A.; Ghughre, S.S.; Krishichayan; Mukhopadhyay, S.; Gangopadhyay, G.; Singh, A.K.

    2007-01-01

    The nucleus 144 Sm (Z=62, N=82), with its proximity to the shell closure and possibilities of particles and holes occupying high j orbitals, following appropriate excitations, is a suitable system for observation of dipole (MR) bands

  19. Air stability and magnetic properties of GdN, TiN, and (Gd,Ti)N nanoparticles

    International Nuclear Information System (INIS)

    Si Pingzhan; Choi, C. J.; Tegus, O.; Brueck, E.; Geng, D. Y.; Zhang, Z. D.

    2008-01-01

    GdN, TiN, and (Gd,Ti)N nanoparticles were prepared by arc evaporating Gd, Ti, and Gd-Ti alloys in N 2 , respectively. Most of these nanoparticles show narrow size distribution with average diameter of 20 nm. Shell/core structure was observed in the (Gd,Ti)N nanoparticles, in which the shell was formed by surface reaction with air. (Gd,Ti)N nanoparticles are more stable than GdN nanoparticles in air due partially to the formation of the protective shell. The Curie temperature of GdN nanoparticles is lower than that of the bulk GdN. Both GdN and (Gd, Ti)N nanoparticles are difficult to reach magnetic saturation and show zero coercivity

  20. Favored neutron excitations in superdeformed 147Gd

    International Nuclear Information System (INIS)

    Theisen, C.; Khadiri, N.; Vivien, J.P.; Ragnarsson, I.; Beausang, C.W.; Beck, F.A.; Belier, G.; Byrski, T.; Curien, D.; de France, G.; Disdier, D.; Duchene, G.; Finck, C.; Flibotte, S.; Gall, B.; Haas, B.; Hanine, H.; Herskind, B.; Kharraja, B.; Merdinger, J.C.; Nourreddine, A.; Nyako, B.M.; Perez, G.E.; Prevost, D.; Stezowski, O.; Rauch, V.; Rigollet, C.; Savajols, H.; Sharpey-Schafer, J.; Twin, P.J.; Wei, L.; Zuber, K.

    1996-01-01

    Four new superdeformed (SD) bands have been observed in 147 Gd using the EUROGAM II spectrometer. By comparison with 146,148,149 Gd SD bands, we use the effective alignment to assign excited band configurations, with the support of the Nilsson-Strutinsky cranking formalism. The effect of the crossing of the [642]5/2 and [651]1/2 neutron orbitals lying just below the magic N=86 SD shell gap has been investigated for the 146,147,148 Gd bands. Evidence for the [411]1/2 orbital is also given. copyright 1996 The American Physical Society

  1. NMR-ON of 182Ta and 183Ta in Fe

    International Nuclear Information System (INIS)

    Allsop, A.L.; Chaplin, D.H.; Murray, D.W.; Stone, N.J.

    1980-01-01

    Nuclear magnetic resonance has been observed on radioactive 182 Ta and 183 Ta oriented at low temperature in an Fe host, by detection of the change in spatial anisotropy of γ-rays emitted during nuclear decay. By measuring the resonant frequencies of 183 Ta in four different applied magnetic fields the nuclear magnetic moment and hyperfine field have been deduced. These are: vertical stroke μ( 183 Ta;I = 7/2) = 2.28(3)μsub(N) and Bsub(h)sub(f)(TaFe at 0 K) = -67.2(1.3)T. The sin of the ground state of 182 Ta has been determined as I = 3 by comparing resonance results with those obtained in a thermal equilibrium nuclear orientation study. The ratio of the resonant frequencies observed for 182 Ta and 183 Ta at one applied field value yields a magnetic moment for the former of vertical stroke μ( 182 Ta;I = 3) vertical stroke = 2.91(3)μsub(N). The spin lattice relaxation time for 183 TaFe (0.12 at% Ta) at 18 mK in an applied field of 0.5 T has been found to be 40(10)s. (orig.)

  2. The SM and MIR reactors operation experience

    International Nuclear Information System (INIS)

    Kuprienko, V.A.; Klinov, A.V.; Svyatkin, M.N.; Shamardin, V.K.

    1995-01-01

    The SM and MIR operation experience show that continuous work on the problem of ageing, in all its aspects, allows for prolongation of the research plant life cycle by several folds as compared to the initial project. The redesigned SM-3 reactor will operate for another 20 years. The similar result is expected from the MIR planned reconstruction which scope will be the topic of future presentations. (orig.)

  3. Stoichiometry behavior of TaN, TaCN and TaC thin films produced by magnetron sputtering

    International Nuclear Information System (INIS)

    Vargas, M.; Castillo, H.A.; Restrepo-Parra, E.; De La Cruz, W.

    2013-01-01

    Thin films were synthesized in a magnetron sputtering system using a target of Ta with 99.99% purity and silicon substrates (1 1 1). The gases used for the film growth were (Ar + N 2 ), (Ar + CH 4 + N 2 ) and (Ar + CH 4 ) mixtures for TaN, TaCN and TaC, respectively. The substrate temperature increased from room temperature to 500 °C. The chemical composition and bonding configuration were examined using X-ray photoelectron spectroscopy (XPS), revealing Ta-N, Ta-C-N, Ta-C and C-C bonds. Moreover, the crystallographic structure was analyzed using X-ray diffraction (XRD), indicating the presence of (1 1 1) and (2 0 0) planes belonging to a face-centered cubic structure. The stoichiometry variation dependence on the CH 4 and N 2 flow was analyzed, and the influence of the substrate temperature on the coatings was investigated. Finally, scanning electron microscopy (SEM) was used to determine the evolution on the grain formation in the coatings as the substrate temperature increased.

  4. Stoichiometry behavior of TaN, TaCN and TaC thin films produced by magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, M. [Centro de Nanociencia y Nanotecnología, Universidad Nacional Autónoma de México, A.P. 2681, C.P. 22860, Ensenada, B.C. (Mexico); Castillo, H.A. [Centro de Enseñanza Técnica y Superior, CETYS Universidad, Campus Tijuana, Tijuana, B.C. (Mexico); Restrepo-Parra, E., E-mail: erestrepopa@unal.edu.co [Universidad Nacional de Colombia Sede Medellín Colombia, Facultad de Minas, Manizales (Colombia); De La Cruz, W. [Centro de Nanociencia y Nanotecnología, Universidad Nacional Autónoma de México, A.P. 2681, C.P. 22860, Ensenada, B.C. (Mexico)

    2013-08-15

    Thin films were synthesized in a magnetron sputtering system using a target of Ta with 99.99% purity and silicon substrates (1 1 1). The gases used for the film growth were (Ar + N{sub 2}), (Ar + CH{sub 4} + N{sub 2}) and (Ar + CH{sub 4}) mixtures for TaN, TaCN and TaC, respectively. The substrate temperature increased from room temperature to 500 °C. The chemical composition and bonding configuration were examined using X-ray photoelectron spectroscopy (XPS), revealing Ta-N, Ta-C-N, Ta-C and C-C bonds. Moreover, the crystallographic structure was analyzed using X-ray diffraction (XRD), indicating the presence of (1 1 1) and (2 0 0) planes belonging to a face-centered cubic structure. The stoichiometry variation dependence on the CH{sub 4} and N{sub 2} flow was analyzed, and the influence of the substrate temperature on the coatings was investigated. Finally, scanning electron microscopy (SEM) was used to determine the evolution on the grain formation in the coatings as the substrate temperature increased.

  5. Gamma ray irradiation characteristics of SM fibers

    International Nuclear Information System (INIS)

    Ito, Ryuichi; Okano, Hiroaki; Hashiba, Keichi; Nakai, Hisanori

    1987-01-01

    1.3 μm range single mode (SM) optical fibers have been used for wide application of mainly long distance communication. At present, in order to realize the larger capacity and longer distance between relay points, the development of 1.5 μm range SM fibers of low dispersion and small loss has been actively promoted. As for the radiation withstanding property of SM fibers, report is scarce. The authors reported on the gamma ray irradiation characteristics of 1.3 μm range SM fibers, but since 1.5 μm range SM fibers are designed with the different structure from that of 1.3 μm fibers, it is necessary to evaluate from new viewpoint. In this report, mainly on the structure having triangular distribution, the effect that the manufacturing condition and the structural defects of glass exert on the gamma ray irradiation characteristics is described. The specimens were mainly dispersion shift type fibers (DSF), and for comparison, single window, double window and 1.3 μm SM fibers were examined. Co-60 gamma ray was irradiated, and the optical loss and electron spin resonance were measured. By low temperature and low speed drawing, the good result in the optical loss was obtained. The presence of oxygen at the time of sintering materials had no effect. The dependence of the ESR on the drawing condition was not very remarkable. (Kako, I.)

  6. TaEDS1 genes positively regulate resistance to powdery mildew in wheat.

    Science.gov (United States)

    Chen, Guiping; Wei, Bo; Li, Guoliang; Gong, Caiyan; Fan, Renchun; Zhang, Xiangqi

    2018-04-01

    Three EDS1 genes were cloned from common wheat and were demonstrated to positively regulate resistance to powdery mildew in wheat. The EDS1 proteins play important roles in plant basal resistance and TIR-NB-LRR protein-triggered resistance in dicots. Until now, there have been very few studies on EDS1 in monocots, and none in wheat. Here, we report on three common wheat orthologous genes of EDS1 family (TaEDS1-5A, 5B and 5D) and their function in powdery mildew resistance. Comparisons of these genes with their orthologs in diploid ancestors revealed that EDS1 is a conserved gene family in Triticeae. The cDNA sequence similarity among the three TaEDS1 genes was greater than 96.5%, and they shared sequence similarities of more than 99.6% with the respective orthologs from diploid ancestors. The phylogenetic analysis revealed that the EDS1 family originated prior to the differentiation of monocots and dicots, and EDS1 members have since undergone clear structural differentiation. The transcriptional levels of TaEDS1 genes in the leaves were obviously higher than those of the other organs, and they were induced by Blumeria graminis f. sp. tritici (Bgt) infection and salicylic acid (SA) treatment. The BSMV-VIGS experiments indicated that knock-down the transcriptional levels of the TaEDS1 genes in a powdery mildew-resistant variety of common wheat compromised resistance. Contrarily, transient overexpression of TaEDS1 genes in a susceptible common wheat variety significantly reduced the haustorium index and attenuated the growth of Bgt. Furthermore, the expression of TaEDS1 genes in the Arabidopsis mutant eds1-1 complemented its susceptible phenotype to powdery mildew. The above evidences strongly suggest that TaEDS1 acts as a positive regulator and confers resistance against powdery mildew in common wheat.

  7. Time domain simulation of Gd3+-Gd3+ distance measurements by EPR

    Science.gov (United States)

    Manukovsky, Nurit; Feintuch, Akiva; Kuprov, Ilya; Goldfarb, Daniella

    2017-07-01

    Gd3+-based spin labels are useful as an alternative to nitroxides for intramolecular distance measurements at high fields in biological systems. However, double electron-electron resonance (DEER) measurements using model Gd3+ complexes featured a low modulation depth and an unexpected broadening of the distance distribution for short Gd3+-Gd3+ distances, when analysed using the software designed for S = 1/2 pairs. It appears that these effects result from the different spectroscopic characteristics of Gd3+—the high spin, the zero field splitting (ZFS), and the flip-flop terms in the dipolar Hamiltonian that are often ignored for spin-1/2 systems. An understanding of the factors affecting the modulation frequency and amplitude is essential for the correct analysis of Gd3+-Gd3+ DEER data and for the educated choice of experimental settings, such as Gd3+ spin label type and the pulse parameters. This work uses time-domain simulations of Gd3+-Gd3+ DEER by explicit density matrix propagation to elucidate the factors shaping Gd3+ DEER traces. The simulations show that mixing between the |+½, -½> and |-½, +½> states of the two spins, caused by the flip-flop term in the dipolar Hamiltonian, leads to dampening of the dipolar modulation. This effect may be mitigated by a large ZFS or by pulse frequency settings allowing for a decreased contribution of the central transition and the one adjacent to it. The simulations reproduce both the experimental line shapes of the Fourier-transforms of the DEER time domain traces and the trends in the behaviour of the modulation depth, thus enabling a more systematic design and analysis of Gd3+ DEER experiments.

  8. Safety assessment for TA-48 radiochemical operations

    International Nuclear Information System (INIS)

    1994-08-01

    The purpose of this report is to document an assessment performed to evaluate the safety of the radiochemical operations conducted at the Los Alamos National Laboratory operations area designated as TA-48. This Safety Assessment for the TA-48 radiochemical operations was prepared to fulfill the requirements of US Department of Energy (DOE) Order 5481.1B, ''Safety Analysis and Review System.'' The area designated as TA-48 is operated by the Chemical Science and Technology (CST) Division and is involved with radiochemical operations associated with nuclear weapons testing, evaluation of samples collected from a variety of environmental sources, and nuclear medicine activities. This report documents a systematic evaluation of the hazards associated with the radiochemical operations that are conducted at TA-48. The accident analyses are limited to evaluation of the expected consequences associated with a few bounding accident scenarios that are selected as part of the hazard analysis. Section 2 of this report presents an executive summary and conclusions, Section 3 presents pertinent information concerning the TA-48 site and surrounding area, Section 4 presents a description of the TA-48 radiochemical operations, and Section 5 presents a description of the individual facilities. Section 6 of the report presents an evaluation of the hazards that are associated with the TA-48 operations and Section 7 presents a detailed analysis of selected accident scenarios

  9. Curie temperature rising by fluorination for Sm2Fe17

    Directory of Open Access Journals (Sweden)

    Matahiro Komuro

    2013-02-01

    Full Text Available Fluorine atoms can be introduced to Sm2Fe17 using XeF2 below 423 K. The resulting fluorinated Sm2Fe17 powders have ferromagnetic phases containing Sm2Fe17FY1(0Sm2Fe17FY2 (1Sm2Fe17, and α-Fe. The unit cell for Sm2Fe17 is elongated by the fluorination. The largest unit cell volume among the rhombohedral Sm2Fe17 compounds is 83.8 nm3, which is 5.8% larger than Sm2Fe17. The rhombohedral Sm2Fe17 with the largest unit cell volume is dissociated above 873 K, and fluorination increases Curie temperature from 403 K for Sm2Fe17 to 675 K. This increase can be explained by the magneto-volume effect.

  10. μ+ depolarization in AlGd alloys

    International Nuclear Information System (INIS)

    Kohn, S.; Brown, J.A.; Heffner, R.H.; Huang, C.Y.; Kitchens, T.A. Jr.; Leon, M.; Olsen, C.E.; Schillaci, M.E.

    1979-01-01

    The μ + depolarization rate in dilute AlGd alloys containing 50 and 450 atomic ppm Gd was measured in a transverse field of 80 Oe over the temperature range 6-300 K. For both alloys, Λ increased dramatically above 200 K, reaching values of 0.69 and 0.93 μs -1 , respectively, near room temperature. The results are interpreted as providing evidence for a thermally-activated trapping mechanism. (Auth.)

  11. Field investigations of soils at TA-19, TA-26, TA-73 and TA-0, SWMU aggregate 0-D and 016

    International Nuclear Information System (INIS)

    McFadden, L.D.

    1995-01-01

    Field based investigations of the general soil-geomorphic characteristics were carried out at TA-19, -26, -73, -0, Aggregate 0-D and -016 in order to provide information for utilization in ongoing and anticipated LANL ERP (Environmental Restoration Project) activities at these sites. These investigations show that soils exhibiting diverse morphologic character, varying ages, and relations to landforms characterize these sites. A review of recent and ongoing soils studies also shows that soil textural, chemical, and mineralogical characteristics may profoundly influence the migration and/or retardation of a variety of potential contaminants initially placed in direct contact with soils, or that encounter soils during subsurface percolation or discharge. Soil-geomorphic relations also provide important insights into recent site erosion, deposition or other surficial processes that must, be considered as part of environmental assessment of a given site and remediation; and, the planned geomorphic mapping activities at each site, as well as other associated activities (e.g, geophysical survey, site sampling) are accordingly appropriate and necessary with respect to identification of significant soil relations at each site. Specific and general recommendations in consideration of important findings regarding the possible impacts of soil development of the nature of contaminant behavior at various sites are provided to help guide sampling and analysis activities during ERP investigations outlined in the RFI Work Plan for Operational Unit-1071

  12. Evaluation of Gd and Gd{sup 159} as new approaches for cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Galvao, I.; Neves, M.J., E-mail: nevesmj@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Grupo de Desenvolvimento de Radiofarmacos; Santos, R.G., E-mail: santosr@cdtn.br [Instituto Nacional de Ciencia e Tecnologia em Medicina Molecular (INCT-MM), Belo Horizonte, MG (Brazil)

    2011-07-01

    Metal compounds have shown many biological activities and have been successfully used as anticancer agents such cisplatin. Actually gadolinium (Gd) complexed with a porphyrin Motexafin (MGd) has been investigated as redox-active compound for treatment of cancer. 1{sup 59G}d decays by beta emission with an energy of 970 keV and half-life of 18.59 hours. The de-excitation can be via gamma ray and internal conversion electron emission followed by auger electrons and x rays. Considering all of this 1{sup 59G}d could be a interesting radionuclide to be as a radio therapeutical agent. The aims of this works were to evaluate the cytotoxicity of Gd and 1{sup 59G}d on malignant brain tumors such as glioblastoma multiform, the most frequent brain tumors which has a very poor prognosis. For this purpose, it was used human glioblastoma cell lines T98 (mutant p53) and U87 (wild-type p53) to investigate the cytotoxicity of gadolinium on cell metabolism by MTT assay and also morphological changes, chromatin condensation by DAPI assay and ROS generation. Gadolinium was able to decrease cell viability, the cells presented morphological changes like round shapes and blebs formation after cell treatment with 5x10{sup -6}M of Gd. Nuclear changing and ROS generation occurred in a dose dependent way indicating the cytotoxic effect of Gd. Treatment with 1{sup 59G}d increased all of changes observed with treatment with Gd. These results state for an additive effect of metal toxicity and radioactivity inducing ROS generation as the main mechanism of anti tumoral action of 1{sup 59G}d. The results obtained indicated that the radioactive analogues of Gd have increased cytotoxic effects and gadolinium can be a metal of choice for development of new drugs for cancer treatment. (author)

  13. Description and exploitation of benchmarks involving {sup 149}Sm, a fission product taking part of the burn up credit in spent fuels

    Energy Technology Data Exchange (ETDEWEB)

    Anno, J.; Poullot, G. [CEA Centre d`Etudes de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire; Fouillaud, P.; Grivot, P. [CEA Centre d`Etudes de Valduc, 21 - Is-sur-Tille (France)

    1995-12-31

    Up to now, there was no benchmark to validate the Fission Products (FPs) cross sections in criticality safety calculations. The protection and nuclear safety institute (IPSN) has begun an experimental program on 6 FPs ({sup 103}Rh, {sup 133}Cs, {sup 143}Nd, {sup 149}Sm, {sup 152}Sm, and {sup 155}Gd daughter of {sup 155}Eu) giving alone a decrease of reactivity equal to half the whole FPs in spent fuels (except Xe and I). Here are presented the experiments with the {sup 149}Sm and the results obtained with the APOLLO I-MORET III calculations codes. 11 experiments are carried out in a zircaloy tank of 3.5 1 containing slightly nitric acid solutions of Samarium (96,9% in weight of {sup 149S}m) at 0.1048 -0.2148 - 0.6262 g/l concentrations. It was placed in the middle of arrays of UO{sub 2} rods (4.742 % U5 weight %) at square pitch of 13 mm. The underwater height of the rods is the critical parameter. In addition, 7 experiments were performed with the same apparatus with water and boron proving a good experimental representativeness and a good accuracy of the calculations. As the reactivity worth of the Sm tank is between 2000 and 6000 10{sup -5}, the benchmarks are well representative and the cumulative absorption ratios show that {sup 149}Sm is well qualified under 1 eV. (authors). 8 refs., 7 figs., 6 tabs.

  14. Anodic oxidation of Ta/Fe alloys

    International Nuclear Information System (INIS)

    Mato, S.; Alcala, G.; Thompson, G.E.; Skeldon, P.; Shimizu, K.; Habazaki, H.; Quance, T.; Graham, M.J.; Masheder, D.

    2003-01-01

    The behaviour of iron during anodizing of sputter-deposited Ta/Fe alloys in ammonium pentaborate electrolyte has been examined by transmission electron microscopy, Rutherford backscattering spectroscopy, glow discharge optical emission spectroscopy and X-ray photoelectron spectroscopy. Anodic films on Ta/1.5 at.% Fe, Ta/3 at.% Fe and Ta/7 at.% Fe alloys are amorphous and featureless and develop at high current efficiency with respective formation ratios of 1.67, 1.60 and 1.55 nm V -1 . Anodic oxidation of the alloys proceeds without significant enrichment of iron in the alloy in the vicinity of the alloy/film interface and without oxygen generation during film growth, unlike the behaviour of Al/Fe alloys containing similar concentrations of iron. The higher migration rate of iron species relative to that of tantalum ions leads to the formation of an outer iron-rich layer at the film surface

  15. The Cloud2SM Project

    Science.gov (United States)

    Crinière, Antoine; Dumoulin, Jean; Mevel, Laurent; Andrade-Barosso, Guillermo; Simonin, Matthieu

    2015-04-01

    From the past decades the monitoring of civil engineering structure became a major field of research and development process in the domains of modelling and integrated instrumentation. This increasing of interest can be attributed in part to the need of controlling the aging of such structures and on the other hand to the need to optimize maintenance costs. From this standpoint the project Cloud2SM (Cloud architecture design for Structural Monitoring with in-line Sensors and Models tasking), has been launched to develop a robust information system able to assess the long term monitoring of civil engineering structures as well as interfacing various sensors and data. The specificity of such architecture is to be based on the notion of data processing through physical or statistical models. Thus the data processing, whether material or mathematical, can be seen here as a resource of the main architecture. The project can be divided in various items: -The sensors and their measurement process: Those items provide data to the main architecture and can embed storage or computational resources. Dependent of onboard capacity and the amount of data generated it can be distinguished heavy and light sensors. - The storage resources: Based on the cloud concept this resource can store at least two types of data, raw data and processed ones. - The computational resources: This item includes embedded "pseudo real time" resources as the dedicated computer cluster or computational resources. - The models: Used for the conversion of raw data to meaningful data. Those types of resources inform the system of their needs they can be seen as independents blocks of the system. - The user interface: This item can be divided in various HMI to assess maintaining operation on the sensors or pop-up some information to the user. - The demonstrators: The structures themselves. This project follows previous research works initiated in the European project ISTIMES [1]. It includes the infrared

  16. Resonances in odd-odd 182Ta

    Science.gov (United States)

    Brits, C. P.; Wiedeking, M.; Bello Garrote, F. L.; Bleuel, D. L.; Giacoppo, F.; Görgen, A.; Guttormsen, M.; Hadynska-Klek, K.; Hagen, T. W.; Ingeberg, V. W.; Kheswa, B. V.; Klintefjord, M.; Larsen, A. C.; Malatji, K. L.; Nyhus, H. T.; Papka, P.; Renstrøm, T.; Rose, S.; Sahin, E.; Siem, S.; Tveten, G. M.; Zeiser, F.

    2017-09-01

    Enhanced γ-decay on the tail of the giant electric dipole resonance, such as the scissors or pygmy resonances, can have significant impact on (n,γ) reaction rates. These rates are important input for modeling processes that take place in astrophysical environments and nuclear reactors. Recent results from the University of Oslo indicate the existence of a significant enhancement in the photon strength function for nuclei in the actinide region due to the scissors resonance. Further, the M1 strength distribution of the scissors resonances in rare earth nuclei has been studied extensively over the years. To investigate the evolution and persistence of the scissor resonance in other mass regions, an experiment was performed utilizing the NaI(Tl) γ-ray detector array (CACTUS) and silicon particle telescopes (SiRi) at the University of Oslo Cyclotron laboratory. Particle-γ coincidences from the 181Ta(d,p)182Ta and 181Ta(d,d')181Ta reactions were used to measure the nuclear level density and photon strength function of the well-deformed 181Ta and 182Ta systems, to investigate the existence of resonances below the neutron separation energy. Note to the reader: the title of this article has been corrected on September 19, 2017.

  17. Characterization of Rh films on Ta(110)

    International Nuclear Information System (INIS)

    Jiang, L.Q.; Ruckman, M.W.; Strongin, M.

    1989-01-01

    The surface and electronic structure of Rh films on Ta(110) up to several monolayers thick on Ta(110) are characterized by photoemission, Auger emission, low energy electron diffraction and low energy ion scattering. From the variation of the Rh Auger peak-to-peak intensity as a function of evaporation time, Rh/Ta(110) appears to grow in the Stranski-Krastanov mode at room temperature. However, the LEIS data show that the Rh adatoms begin to cluster on Ta(110) before growth of the monolayer is completed. Diffuse LEED scattering suggests that the Rh films are disordered. Photoemission shows that Rh chemisorption on Ta(110) generates two peaks located at 1.2 and 2. 5 eV binding energy during the initial phase of thin film growth (0 3.7 ML). Photoemission data for CO covered surfaces show that CO dissociates on the Rh/Ta(110) surface for Rh coverages less than 2.5 ML and also show that the Rh clusters develop at least one site capable of molecular CO adsorption above 0.3 ML Rh coverage. 38 refs., 5 figs

  18. Resonances in odd-odd 182Ta

    Directory of Open Access Journals (Sweden)

    Brits C.P.

    2017-01-01

    Full Text Available Enhanced γ-decay on the tail of the giant electric dipole resonance, such as the scissors or pygmy resonances, can have significant impact on (n,γ reaction rates. These rates are important input for modeling processes that take place in astrophysical environments and nuclear reactors. Recent results from the University of Oslo indicate the existence of a significant enhancement in the photon strength function for nuclei in the actinide region due to the scissors resonance. Further, the M1 strength distribution of the scissors resonances in rare earth nuclei has been studied extensively over the years. To investigate the evolution and persistence of the scissor resonance in other mass regions, an experiment was performed utilizing the NaI(Tl γ-ray detector array (CACTUS and silicon particle telescopes (SiRi at the University of Oslo Cyclotron laboratory. Particle-γ coincidences from the 181Ta(d,p182Ta and 181Ta(d,d'181Ta reactions were used to measure the nuclear level density and photon strength function of the well-deformed 181Ta and 182Ta systems, to investigate the existence of resonances below the neutron separation energy.

  19. Sorption and desorption of cesium and strontium on TA-2 and TA-41 soils and sediments

    International Nuclear Information System (INIS)

    Kung, K. Stephen; Li, Benjamin W.; Longmire, P.A.; Fowler, M.M.

    1996-04-01

    Current environmental monitoring has detected radioactive contaminants in alluvial groundwater, soils, and sediments in the TA-2 and TA-41 areas along the north central edge of Los Alamos National Laboratory. Because of this contamination, this study was initiated. The objective of this study is to quantify the sorptivity of cesium and strontium onto TA-2 and TA-41 site specific soil samples under a controlled environment in the laboratory. The purposes of this work are to determine cesium and strontium sorption coefficient for these sit specific soils and to evaluate the potential transport of cesium and strontium. Based on this information, a risk assessment and remediation strategy can be developed

  20. High spin states in 143Sm

    International Nuclear Information System (INIS)

    Raut, R.; Ganguly, S.; Kshetri, R.; Banerjee, P.; Bhattacharya, S.; Dasmahapatra, B.; Mukherjee, A.; Mukherjee, G.; Sarkar, M. Saha; Goswami, A.; Gangopadhyay, G.; Mukhopadhyay, S.; Krishichayan,; Chakraborty, A.; Ghughre, S. S.; Bhattacharjee, T.; Basu, S. K.

    2006-01-01

    The high spin states of 143 Sm have been studied by in-beam γ-spectroscopy following the reaction 130 Te( 20 Ne,7n) 143 Sm at E lab =137 MeV, using a Clover detector array. More than 50 new gamma transitions have been placed above the previously known J π =23/2 - , 30 ms isomer at 2795 keV. The level scheme of 143 Sm has been extended up to 12 MeV and spin-parity assignments have been made to most of the newly proposed level. Theoretical calculation with the relativistic mean field approach using blocked BCS method, has been performed. A sequence of levels connected by M1 transitions have been observed at an excitation energy ∼8.6 MeV. The sequence appears to be a magnetic rotational band from systematics

  1. Giant magnetocaloric effect in Gd5(Si2Ge2 alloy with low purity Gd

    Directory of Open Access Journals (Sweden)

    Cleber Santiago Alves

    2004-12-01

    Full Text Available Gd5(Ge1-xSi x, x < 4 based alloys are potential candidates for magnetic refrigeration in the range ~20 - ~290 K. However, one of the greatest obstacles for the use of that technology in large scale is the utilization of high pure Gd metal (99.99 wt. (% to produce the GdGeSi alloys, since the impurity elements decrease the intensity of the magnetocaloric effect (EMC¹. In this work, we prove that annealing of the Gd5Ge2Si2 can promote remarkable values for the EMC in comparison to those obtained for the alloy with high pure Gd. Also, the as cast alloy and the annealed alloy are not monophasic, but have at least two crystalline phases in their microstructure. Results for X-ray analysis, optical and electronic microscopy and magnetization measurements are reported.

  2. Conceptual Design Plan SM-43 Replacement Project

    Energy Technology Data Exchange (ETDEWEB)

    University of California, Los Alamos National Laboratory, SCC Project Office

    2000-11-01

    The Los Alamos National Laboratory Conceptual Design Plan for the SM-43 Replacement Project outlines plans for replacing the SM-43 Administration Building. Topics include the reasons that replacement is considered a necessity; the roles of the various project sponsors; and descriptions of the proposed site and facilities. Also covered in this proposal is preliminary information on the project schedule, cost estimates, acquisition strategy, risk assessment, NEPA strategy, safety strategy, and safeguards and security. Spreadsheets provide further detail on space requirements, project schedules, and cost estimates.

  3. Sm 3+-doped polymer optical waveguide amplifiers

    Science.gov (United States)

    Huang, Lihui; Tsang, Kwokchu; Pun, Edwin Yue-Bun; Xu, Shiqing

    2010-04-01

    Trivalent samarium ion (Sm 3+) doped SU8 polymer materials were synthesized and characterized. Intense red emission at 645 nm was observed under UV laser light excitation. Spectroscopic investigations show that the doped materials are suitable for realizing planar optical waveguide amplifiers. About 100 μm wide multimode Sm 3+-doped SU8 channel waveguides were fabricated using a simple UV exposure process. At 250 mW, 351 nm UV pump power, a signal enhancement of ˜7.4 dB at 645 nm was obtained for a 15 mm long channel waveguide.

  4. Magnetic ordering of GdMn2

    International Nuclear Information System (INIS)

    Ouladdiaf, B.; Ritter, C.; Ballou, R.; Deportes, J.

    1999-01-01

    Complete text of publication follows. GdMn 2 crystallizes in the C15 cubic Laves phase structure. Within this structure Mn atoms lie at the vertices of regular tetrahedra stacked in the diamond arrangement connected by sharing vertices, leading to a strong geometric frustration. An antiferromagnetic magnetic order sets in below T N ∼ 105 K. It gives rise to a large magnetovolume effect (ΔV/V ∼ 1%). Thermal expansion data show two anomalies at 105 K and 35 K. The second anomaly was often interpreted as the ferromagnetic ordering of Gd sublattice. Moessbauer data indicate however, that Gd sublattice orders at T N ∼ 105 K as the Mn moments. Elastic neutron scattering measurements were performed using short wavelength neutron beam (λ = 0.5 A) on D9 at ILL. No magnetic contribution to the nuclear peaks was found excluding thereby any K = [0 0 0] component. However antiferromagnetic peaks indexed by a propagation vector [2/3 2/3 0] were observed leading to a non collinear magnetic arrangement of both Mn and Gd sublattices. The results are discussed by invoking the geometric frustration associated with the Mn atomic packing and the singlet state of the Gd ions. (author)

  5. Medium-spin levels and the character of the 20.4 ns 13/2+ isomer in 145Gd

    International Nuclear Information System (INIS)

    Pakkanen, A.; Muhonen, J.; Piiparinen, M.

    1981-06-01

    Levels of the N = 81 nucleus 145 Gd have been investigated by in-beam γ-ray and conversion electron spectroscopy with the 144 Sm( 3 He,2n) reaction. Fourteen new low- and medium-spin states between 1.0 and 2.4 MeV excitation, the known yrast levels up to spin (21/2) + , five other high-spin non-yrast states and a new 20.4 ns (13/2) + isomer at 2200.2 keV in 145 Gd have been observed. The isomer decays via a fast 927.3 keV E3 transition with B(E3) = 48 +- 7 W.u. Another weaker decay branch is a mixed, strongly hindered E1+M2+E3 transition to the νhsub(11/2)sup(-1) state. We propose an octupole νfsub(7/2)jsub(0)sup(-2)x3 - main configuration for the isomer, analogous to the 997 keV (13/2) + isomer in 147 Gd. The levels of 145 Gd are discussed on the basis of the spherical shell model. (author)

  6. An investigation of the Pd-Ag-Ru-Gd quaternary system phase diagram

    International Nuclear Information System (INIS)

    Zhang Kanghou; Xu Yun

    2005-01-01

    On the basis of the Ag-Pd-Gd, Ag-Ru-Gd and Pd-Ru-Gd ternary systems, the partial phase diagram of Pd-Ag-Ru-Gd (Gd 3 Gd and Ag 51 Gd 14 ; five two-phase regions: Pd(Ag) + (Ru), Pd(Ag) + Ag 51 Gd 14 (Ru) + Ag 51 Gd 14 , Pd(Ag) + Pd 3 Gd and (Ru) + Pd 3 Gd; three three-phase regions: Pd(Ag) + Pd 3 Gd + (Ru), Pd(Ag) + Ag 51 Gd 14 + (Ru) and (Ru) + Ag 51 Gd 14 + Pd 3 Gd; one four-phase region Pd(Ag) + (Ru) + Ag 51 Gd 14 + Pd 3 Gd. No new quaternary intermetallic phase has been found

  7. Gd(III)-nanodiamond conjugates for MRI contrast enhancement

    Science.gov (United States)

    Manus, Lisa M.; Mastarone, Daniel J.; Waters, Emily A.; Zhang, Xue-Qing; Schultz-Sikma, Elise A.; MacRenaris, Keith W.; Ho, Dean

    2010-01-01

    A Gd(III)-nanodiamond conjugate [Gd(III)-ND] was prepared and characterized, enabling detection of nanodiamonds by MR imaging. The Gd(III)-ND particles significantly reduced the T1 of water protons with a per-Gd(III) relaxivity of 58.82 ± 1.18 mM−1s−1 at 1.5 Tesla (60 MHz). This represents a tenfold increase compared to the monomer Gd(III) complex (r1 = 5.42 ± 0.20 mM−1s−1) and is among the highest per-Gd(III) relaxivities reported. PMID:20038088

  8. Phase equilibria and crystal chemistry of the CaO-½Gd2O3-CoOz system at 885 °C in air

    Science.gov (United States)

    Wong-Ng, W.; Laws, W.; Lapidus, S. H.; Ribaud, L.; Kaduk, J. A.

    2017-10-01

    The CaO-½Gd2O3-CoOz system prepared at 885 °C in air consists of two thermoelectric calcium cobaltate compounds, namely, the 2D thermoelectric oxide solid solution, (Ca3-xGdx)Co4O9-z (0 ≤ x ≤ 0.42) which has a misfit layered structure, and the 1D Ca3Co2O6 compound which consists of chains of alternating CoO6 trigonal prisms and CoO6 octahedra. Ca3Co2O6 was found to be a point compound. In the peripheral binary systems, Gd was not present in the Ca site of CaO, while a small solid solution region was identified for (Gd1-xCax)O(3-z)/2 (0 ≤ x ≤ 0.075). A solid solution region of distorted perovskite, (Gd1-xCax)CoO3-z (0 ≤ x ≤ 0.24, space group Pnma) was established. The structure of a member of the solid solution, (Gd0.92Ca0.08)CoO3-z, was determined using high resolution synchrotron radiation. A ternary oxide compound CaGdCoO4-z which has an orthorhombic structure (Bmab) was found to be stable at this temperature. Five solid solution tie-line regions and six three-phase regions were determined in the CaO-½Gd2O3-CoOz system. A comparison of the phase diagrams of the CaO-½R2O3-CoOz (R = La, Sm and Gd) systems is provided.

  9. Tribological properties of self-lubricating Ta-Cu films

    Science.gov (United States)

    Qin, Wen; Fu, Licai; Zhu, Jiajun; Yang, Wulin; Li, Deyi; Zhou, Lingping

    2018-03-01

    In this paper, Ta and TaCu films were deposited by using magnetron sputtering, and the tribological properties of the films against Si3N4 balls were investigated under the loads of 2 N and 5 N. The average grain sizes of both films are below 25 nm. Ta and TaCu films have approximate hardness. While the wear rate of TaCu film is much smaller than that of Ta film. Post-wear testing XRD, Raman and XPS revealed the formation of tantalum oxide on the worn surface of both Ta and TaCu films. Tantalum oxidation is effectively lubricating to reduce friction coefficient. So the friction coefficient of both Ta and TaCu film is about 0.45 under different applied loads. Meanwhile, the addition of Cu could increase the toughness of the film, and avoid the generation of wear debris, resulting in a significant increase in wear resistance.

  10. Effect of Ta content on martensitic transformation behavior of RuTa ultrahigh temperature shape memory alloys

    International Nuclear Information System (INIS)

    He Zhirong; Zhou Jingen; Furuya, Y.

    2003-01-01

    Effects of Ta content on martensitic transformation (MT) behavior of Ru 100-x Ta x (x=46-54 at.%) alloys have been investigated by differential scanning calorimetry, dilatometry, X-ray diffraction and optical microscopy. Ta content significantly affects the MT behavior of RuTa alloys. The one-stage reservible MT occurs in Ta-poor RuTa alloys with Ta content less than 49 at.%. The two-stage reservible MT takes place in near-equiatomic RuTa alloys. No reservible MT is observed in Ta-rich alloys with Ta content more then 52 at.% Ta. The MT temperatures and hysteresis of RuTa alloys decrease with increasing Ta content. The aged and thermal cycled processes are nearly no effect on the MT behavior of these alloys. The deforming way of RuTa alloys is twinning. The Ru 50 Ta 50 alloy is of the most excellent MT behavior among these RuTa alloys

  11. Magnetic short-range order in Gd

    International Nuclear Information System (INIS)

    Child, H.R.

    1978-01-01

    The magnetic short-range order in a ferromagnetic, isotopically enriched 160 Gd metal single crystal has been investigated by quasielastic scattering of 81-meV neutrons. Since Gd behaves as an S-state ion in the metal, little anisotropy is expected in its magnetic behavior. However, the data show that there is anisotropic short-range order present over a large temperature interval both above and below T/sub C/. The data have been analyzed in terms of an Ornstein-Zernike Lorentzian form with anisotropic correlation ranges. These correlation ranges as deduced from the observed data behave normally above T/sub C/ but seem to remain constant over a fairly large interval below T/sub C/ before becoming unobservable at lower temperatures. These observations suggest that the magnetic ordering in Gd may be a more complicated phenomenon than first believed

  12. Fabrication and photoluminescence properties of color-tunable light emitting lanthanide doped GdVO4 hierarchitectures

    International Nuclear Information System (INIS)

    Amurisana, Bao; Bao, Lihong; Bao, Liang; Tegus, O.

    2017-01-01

    The flower-like GdVO 4 :Ln 3+ ( Ln 3+ =Eu 3+ , Dy 3+ , Sm 3+ , Tm 3+ ) hierarchitectures have been successfully synthesized on a glass slide substrate through a one-pot hydrothermal route assisted by disodium ethylenediaminetetraacetic acid (Na 2 H 2 L, where L 4- =(CH 2 COO) 2 N(CH 2 ) 2 N(CH 2 COO) 2 4- ). A high density and ordered flower-like GdVO 4 :Ln 3+ hierarchitectures grew epitaxially on glass substrate. The as-prepared flower-like architectures with the size about 6 μm are constructed by the numerous radially oriented single-crystalline nanorods with the width from 20 nm to 200 nm and the length from 500 nm to 3 μm. The morphologies, the thickness, and the density of as-grown flower clusters can be readily tuned by tailoring the growth time and Na 2 H 2 L/Gd 3+ molar ratio. The possible formation mechanism of flower-like GdVO 4 :Ln 3+ hierarchitectures is discussed on the basis of the results from the controlled experiments under hydrothermal conditions. Because of an energy transfer from vanadate groups to dopants, the flower-like GdVO 4 :Ln 3+ ( Ln 3+ =Eu 3+ , Dy 3+ , Sm 3+ and Tm 3+ ) superstructures showed strong characteristic dominant emissions of the Eu 3+ , Dy 3+ , Sm 3+ and Tm 3+ ions at 617 nm ( 5 D 0 → 7 F 2 , strong red), 575 nm ( 4 F 9/2 → 6 H 13/2 , yellow), 604 nm ( 4 G 5/2 → 6 H 7/2 , orange-red) and 476 nm ( 1 G 4 – 3 H 6 , blue) under ultraviolet excitation, respectively.Further, the emission color of the product can also be tuned by selecting the dopant Ln 3+ with characteristic emissions and varying the concentration ratio of co-doping activators. This approach could be extended to the fabrication of hierarchical structures for other oxide micro/nanomaterials, and may provide a general way to achieve multicolor-tunable emission for many applications.

  13. fs - kes ta on ja kust ta tuleb : [luuletused] / [Mesikepp, Indrek] fs

    Index Scriptorium Estoniae

    fs, pseud., 1971-

    2004-01-01

    Sisu: fs - kes ta on ja kust ta tuleb ; "töötasin arhiivis..." ; mustad puud mustas vees ; "on päev. on kylm. on öö..." ; "tead ju kyll..." ; "päiksest paistes päevad..." ; "mida sa teed kui on öö..."

  14. Magnetic and transport properties of amorphous ferro magnetic Gd--Au, Gd--Ni and Gd--Co alloys obtained by splat-cooling

    International Nuclear Information System (INIS)

    Durand, J.; Poon, S.J.

    1977-06-01

    We present the results of magnetization and transport measurements on the amorphous Gd 80 Au 20 , Gd 68 Ni 32 and Gd 67 Co 33 alloys over a temperature range of 1.8 to 300 0 K in fields up to 75 kOe. These ferromagnetic alloys obtained by splat-cooling have Curie temperatures T/sub c/ of 150, 125 and 175 0 K, respectively. The saturation moment per Gd atom extrapolated to 0 0 K is estimated to be 7 +- 0.1 μ/sub B/. The exchange integrals for Gd-Au and Gd-Ni are determined from the value of T/sub c/ and from the temperature dependence of the saturation magnetization. The zero-field resistivity for Gd-Ni and Gd-Co exhibits maxima around T/sub c/. We present some preliminary results of magnetoresistivity measurements with applied field parallel and perpendicular to the foil plane. The anisotropy is in-plane for Gd-Co. For the Gd-Au and Gd-Ni alloys, there is no well-defined easy axis

  15. Ni3d-Gd4f correlation effects on the magnetic behaviour of GdNi

    Energy Technology Data Exchange (ETDEWEB)

    Paulose, P L [Tata Inst. of Fundamental Research, Bombay (India); Patil, Sujata [Tata Inst. of Fundamental Research, Bombay (India); Mallik, R [Tata Inst. of Fundamental Research, Bombay (India); Sampathkumaran, E V [Tata Inst. of Fundamental Research, Bombay (India); Nagarajan, V [Tata Inst. of Fundamental Research, Bombay (India)

    1996-07-01

    The results of magnetization and heat-capacity measurements on the alloys, Gd{sub 1-x}Y{sub x}Ni (x=0.0, 0.25, 0.5, 0.75 and 0.9) are reported. The data suggest that there is a Gd induced magnetic moment on Ni, which may in turn enhance Gd-Gd exchange interaction strength in GdNi. The induced moment (on Ni) apparently exhibits itinerant ferromagnetism in the magnetically ordered state of GdNi. (orig.).

  16. Photoluminescence related to Gd3+:N-vacancy complex in GaN:Gd multi-quantum wells

    International Nuclear Information System (INIS)

    Almokhtar, Mohamed; Emura, Shuichi; Koide, Akihiro; Fujikawa, Takashi; Asahi, Hajime

    2015-01-01

    Highlights: • We grew Gd-doped GaN multi-quantum wells (MQWs) with quantum layer thickness of one nm by MBE. • The X-ray absorption near edge structure spectra observed at Gd LIII-edge indicate a nitrogen vacancy adjacent to Gd substituting the Ga ion in Gd-doped GaN MQW. • The photoluminescence of the samples is discussed considering the formation of a Gd 3+ :Nitrogen-vacancy complex. • A model is presented considering exciton-polaron formation trapped in defect sites around the Gd 3+ :N-vacancy complex in Gd-doped GaN MQWs. - Abstract: The photoluminescence of Gd-doped GaN multi-quantum wells (MQWs) is presented and discussed considering the formation of a Gd 3+ :Nitrogen-vacancy (N-vacancy) complex. A lower energy photoluminescence peak was observed for the Gd-doped GaN MQW sample with respect to the main peak assigned to a neutral donor bound exciton (D 0 X) of the undoped GaN MQW sample. The X-ray absorption near edge structure spectrum observed at Gd L III -edge indicates a nitrogen vacancy adjacent to the Gd substituting the Ga ion in Gd-doped GaN MQW sample. Local stresses around the Gd dopants in Gd-doped GaN matrix generated due to the larger diameter of the Gd 3+ ion with respect to the Ga 3+ ion can be relieved by the creation of vacancies. The lower formation energy of N-vacancies in GaN matrix introduce them as a preferred candidate to relieve the generated stresses. A Gd 3+ :N-vacancy complex consisting of a Gd 3+ ion and the created nitrogen vacancy adjacent to the Gd 3+ dopant is likely to form in GaN:Gd matrix. The lower photoluminescence peak energy observed in the Gd-doped GaN MQW sample is assigned to the recombination of an exciton captured at the Gd 3+ :N-vacancy complex forming a small polaron-like state. A model is presented considering the small exciton-polaron population in defect sites captured around the Gd 3+ ions in the Gd-doped GaN

  17. Density of salt melts containing KF, KCl, K2TaF7 and Ta2O5

    International Nuclear Information System (INIS)

    Agulyanskij, A.I.; Stangrit, P.T.; Konstantinov, V.I.

    1978-01-01

    The results of density measurements by hydrostatic weighing are given for molten K 2 TaF 7 - KF, K 2 TaF 7 -KCL, K 2 TaF 7 - KF - KCl and K 2 TaF 7 - KF - KCl - Ta 2 O 5 mixtures depending on their temperature and composition. The density of the last two systems was measured at compositions close to those of commercial electrolytes. The obtained specific volume - composition dependencies show that no interaction is taking place in the mixtures studied. It is, therefore, believed that, in the K 2 TaF 7 - KF melt, tantalum is mainly present as a complex TaF 7 2- ion, and, in the K 2 TaF 7 - KCl mlt, a certain amount of TaF 6 - ions may be formed along with TaF 7 2-

  18. Ta thickness-dependent perpendicular magnetic anisotropy features in Ta/CoFeB/MgO/W free layer stacks

    Energy Technology Data Exchange (ETDEWEB)

    Yang, SeungMo; Lee, JaBin; An, GwangGuk [Novel Functional Materials and Devices Lab, The Research Institute for Natural Science, Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of); Kim, JaeHong [Division of Nano-Scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Chung, WooSeong [Nano Quantum Electronics Lab, Department of Electronics and Computer Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Hong, JinPyo, E-mail: jphong@hanyang.ac.kr [Novel Functional Materials and Devices Lab, The Research Institute for Natural Science, Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of); Division of Nano-Scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2015-07-31

    We describe Ta underlayer thickness influence on thermal stability of perpendicular magnetic anisotropy in Ta/CoFeB/MgO/W stacks. It is believed that thermal stability based on Ta underlay is associated with thermally-activated Ta atom diffusion during annealing. The difference in Ta thickness-dependent diffusion behaviors was confirmed with X-ray photoelectron spectroscopy analysis. Along with a feasible Ta thickness model, our observations suggest that an appropriate seed layer choice is needed for high temperature annealing stability, a critical issue in the memory industry. - Highlights: • We observed changes in the diffusion behavior with regard to Ta seed layer thickness. • It was observed that a thinner Ta seed layer induced more annealing-stable features. • However, ultra-thin (0.75 nm) Ta shows unstable characteristics about the annealing process. • It was possibly due to a rugged interface of the Ta layer by the island growth process.

  19. Gd-DTPA-enhanced dynamic MR imaging

    International Nuclear Information System (INIS)

    Frank, J.A.; Choyke, P.L.; Carvlin, M.; Inscoe, S.; Austin, H.; Dwyer, A.J.; Girton, M.; Black, J.

    1988-01-01

    This paper describes dynamic enhanced renal MR imaging, a new method of identifying specific derangements in renal function. Various diuretics were employed in 45 animal experiments to demonstrate the effects on the normal renal enhancement pattern (EP) after Gd-DTPA. Since different diuretics, osmotic (O), carbonic anhydrase (CA), and loop (L), are active at different sites, specific EP alterations are observed. Imaging was performed with 32 5.1-second sequential gradient recalled acquisition in a steady state images following a bolus of Gd-DTPA

  20. Unoccupied surface electronic structure of Gd(0001)

    International Nuclear Information System (INIS)

    Li, D.; Dowben, P.A.; Ortega, J.E.; Himpsel, F.J.

    1994-01-01

    The unoccupied surface electronic structure of Gd(0001) was investigated with high-resolution inverse-photoemission spectroscopy. An empty surface state near E F is observed at bar Γ. Two other surface-sensitive features are also revealed at 1.2 and 3.1 eV above the Fermi level. Hydrogen adsorption on Gd surfaces was used to distinguish the surface-sensitive features from the bulk features. The unoccupied bulk-band critical points are determined to be Γ 3 + at 1.9 eV and A 1 at 0.8 eV

  1. EUSO-TA data and simulations

    Energy Technology Data Exchange (ETDEWEB)

    Bisconti, Francesca [Institut fuer Kernphysik (IKP), Karlsruher Institut fuer Technologie (KIT) (Germany); Collaboration: JEM-EUSO-Collaboration

    2016-07-01

    EUSO-TA is one of the fluorescence cosmic ray detector prototypes developed by the JEM-EUSO Collaboration. The prototype has two 1 m diameter Fresnel lenses and one photo detector module (PDM) as focal surface. The PDM consists of 36 multi-anode photomultiplier tubes from Hamamatsu. The prototype has been designed to get information about the calibration of the Fresnel lense system and the PDM, basic parts of the main space-based fluorescence detector under development. EUSO-TA is located at the Black Rock Mesa site of the Telescope Array project (Utah-USA) and works in parallel with the TA fluorescence detectors since February 2015. During its campaigns, EUSO-TA detects cosmic ray events, as well as the pulsed laser from the Central Laser Facility, necessary for the detector calibration. Also planes and stars signatures are well visible in the data, although out of the scientific purpose. The analysis of EUSO-TA data and the comparison of data with simulations will be shown.

  2. Characterization of Rh films on Ta(110)

    International Nuclear Information System (INIS)

    Jiang, L.Q.; Ruckman, M.W.; Strongin, M.

    1990-01-01

    The surface and electronic structure of Rh films on Ta(110) up to several monolayers thick on Ta(110) are characterized by photoemission, Auger emission, low-energy electron diffraction (LEED) and low-energy ion scattering (LEIS). From the variation of the Rh Auger peak-to-peak intensity as a function of evaporation time, Rh appears to grow in the Stranski--Krastanov mode at room temperature. However, the LEIS data show that the Rh adatoms begin to cluster on Ta(110) before growth of the monolayer is completed. Diffuse LEED scattering suggests that the Rh films are disordered. Photoemission shows that Rh chemisorption on Ta(110) generates two peaks located at -1.5 and -2.5 eV binding energy during the initial phase of thin-film growth (0 3.7 ML). CO dissociates on the Rh/Ta(110) surface for Rh coverages<2.5 ML and the surface develops a site capable of molecular CO adsorption above 0.3-ML Rh coverage

  3. Structure of the semi-decoupled π 1/2[411] band in odd proton nucleus 169Ta

    International Nuclear Information System (INIS)

    Song Hai; Deng Fuguo; Shao Liqin; Zhou Hongyu; Sun Huibin; Lu Jingbin; Zhao Guangyi; Yin Lichang; Liu Yunzuo

    2003-01-01

    High spin states of the odd proton-nucleus 169 Ta have been populated in the reaction 155 Gd( 19 F, 5 n) with beam energies of 97 MeV. Rotational band based on d 3/2 proton 1/2[411] Nilsson state has been pushed up to 39/2 + in the α=1/2 decay sequence. Its signature partner, the α=-1/2 decay sequence with four link transitions has been established and 1/2[411] band in 169 Ta was reassigned to be a semi-decoupled band. The systematics of the signature splitting in the K=1/2 bands in the rear-earth region and the accidental degeneracy conclusion given by the angular projection shell model were discussed

  4. Calorimetric investigation on the Pb-Sm and Sn-Sm alloys

    International Nuclear Information System (INIS)

    Berrada, A.-E.-A.; Claire, Y.; Chafik el Idrissi, M.; Castanet, R.

    1997-01-01

    The integral enthalpy of formation of the Sm-Pb and Sm-Sn melts at 1203 K, h f , was determined by direct reaction calorimetry (drop method) in the Pb and Sn rich sides with the help of a high-temperature Tian-Calvet calorimeter. The results can be fitted respectively with reference to the mole fraction of samarium, x, as follows: f /kJmol -1 =x(1-x)(-109.8 -372.0.7x) with 0 Sm f /kJmol -1 =x(1- x)(-277.0+105.4x) with 0 Sm -1 respectively. Such negative values suggest the existence of a strong short-range order in the liquid state. The stoichiometry and the thermal stability of these associations needs additional thermodynamic determinations concerning mainly the free enthalpy of formation. It will be determined by Knudsen-effusion combined with mass spetrometry in a further work. (orig.)

  5. Experimental MR imaging with Gd-DOTA: Preliminary results

    International Nuclear Information System (INIS)

    Schouman-Claeys, E.; Kien, P.; Caille, J.M.; Bonnemain, B.; Frija, G.

    1986-01-01

    To evaluate the paramagnetic properties of a new gadolinium chelate, Gd-DOTA, in vitro and in vivo MR imaging was performed with a 0.5-T supraconductive magnet. The in vitro study consisted in measuring the MR signal obtained with various concentrations of Gd-DOTA and Gd-DTPA in different solutions. Potentialization of the paramagnetic properties of both DOTA and DTPA can be achieved by deuterium, glycerol, and protein solutions. The in vivo study was performed in rabbits with various experimental lesions. Enhancement of anatomic details was obtained with both Gd-DOTA and Gd-DTPA. There was no significant difference between Gd-DOTA and Gd-DTPA, both for in vitro and in vivo experiments. Gd-DOTA appears to be a potential paramagnetic agent for MR imaging

  6. Magnetic and transport properties of sputtered Gd-Y multilayers

    International Nuclear Information System (INIS)

    Freitas, P.P.; From, M.; Melo, L.V.

    1991-01-01

    Gd-Y-Gd multilayers were prepared that show a magnetoresistance enhancement for an Y layer separation of 30 A. This magnetoresistance enhancement is an interface effect and occurs in samples where some degree of antiferromagnetic coupling is present

  7. Preparation and quality control of {sup 153}Sm radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Swasono, R Tamat; Widyastuti, W; Purwadi, B; Laksmi, I [Radioisotope Production Center - BATAN, Jakarta (Indonesia)

    1998-10-01

    The paper summarizes the preparation and quality control of {sup 153}Sm-EDTMP and three {sup 153}Sm-radiosynovectomy agents. Natural and enriched Sm{sub 2}O{sub 3} (98.7% {sup 152}Sm) irradiated in RSG-GAS 30 MW reactor yielded pure and high specific activity {sup 153}Sm. Labeling of EDTMP with {sup 153}Sm was carried out by mixing {sup 153}SmCl{sub 3} solution of pH 4.0 to an EDTMP solution at room temperature then pH adjustment to 8. The {sup 153}Sm-EDTMP complex was separated from the free {sup 153}Sm{sup +3} on a Chelex 100 column. Radiochemical purity was determined by thin layer chromatography using Cellulose sheets and pyridine: ethanol: water (1: 2: 4) mixture as solvent. The {sup 153}Sm-EDTMP has been shown to be stable for two weeks. Three particulate preparations of {sup 153}Sm used for the irradiation of chronic synovitis have been studied. They are hydroxyapatite particles, human serum albumin microspheres and ferric hydroxide macroaggregates. The {sup 153}Sm-ferric hydroxide macroaggregates were prepared in a single step by coprecipitation of {sup 153}Sm in the formation of Fe(OH){sub 3}. Preparation of {sup 153}Sm-labelled hydroxyapatite particles and {sup 153}Sm-labelled albumin microspheres were carried out by {sup 153}Sm labelling of previously prepared particles. Radiolabelling efficiency were greater than 95% for hydroxyapatite particles and macroaggregates and was lower than 20% for albumin microspheres. The particle sizes were inspected using an optical microscope with a haemocytometer and micrometric ocular. (author)

  8. Tritium diffusion in V, Nb and Ta

    International Nuclear Information System (INIS)

    Qi, Z.; Voelkl, J.; Laesser, R.; Wenzl, H.

    1983-01-01

    Gorsky-effect measurements of the diffusion coefficient of tritium (T) in V, Nb and Ta are reported. The measurements were performed at small T concentrations (less than about 1.4 at%), and in the temperature range from -140 0 C to 100 0 C. Comparison with results obtained for H and D shows an increase of the activation energy with increasing isotopic mass. For Nb and Ta, the pre-exponential factors are identical for all the isotopes, whereas for V this factor is appreciably larger for T than for H and D. The reduction of the relaxation strength in the presence of precipitation allows a rough determination of the solubility limit, which is found to be isotope independent for Nb and Ta. In V, the solubility limit for T is shifted slightly to lower temperatures. The H, D or T induced lattice expansion calculated from the relaxation strength shows no dependence on isotopic mass. (author)

  9. Synthesis of Ni3Ta, Ni2Ta and NiTa by high-energy ball milling and subsequent heat treatment

    International Nuclear Information System (INIS)

    Benites, H.S.N.; Silva, B.P da; Ramos, A.S.; Silva, A.A.A.P.; Coelho, G.C.; Lima, B.B. de

    2014-01-01

    The tantalum has relevance for the development of multicomponent Ni-based superalloys which are hardened by solid solution and precipitation mechanisms. Master alloys are normally used in the production step in order to produce refractory metals and alloys. The present work reports on the synthesis of Ni_3Ta, Ni_2Ta and NiTa by high-energy ball milling and subsequent heat treatment. The elemental Ni-25Ta, Ni-33Ta and Ni-50Ta (at.-%) powder mixtures were ball milled under Ar atmosphere using stainless steel balls and vials, 300 rpm and a ball-to-powder weight ratio of 10:1. Following, the as-milled samples were uniaxially compacted and heat-treated at 1100 deg C for 4h under Ar atmosphere. The characterization of as-milled and heat-treated samples was conducted by means of X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometry. A large amount of Ni_3Ta, Ni_2Ta and NiTa was formed in the mechanically alloyed heat-treated Ni-25Ta, Ni-33Ta and Ni-50Ta alloys. (author)

  10. New AMS method to measure the atom ratio {sup 146}Sm/{sup 147}Sm for a half-life determination of {sup 146}Sm

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, N. [Tandem Accelerator Complex, Research Facility Center for Science and Technology, University of Tsukuba (Japan); Paul, M., E-mail: paul@vms.huji.ac.il [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); Alcorta, M. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Bowers, M.; Collon, P. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); Deibel, C.M. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 46624 (United States); DiGiovine, B. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Goriely, S. [Universite Libre de Bruxelles, CP-226, Brussels 1050 (Belgium); Greene, J.P.; Henderson, D.J.; Jiang, C.L. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Kashiv, Y. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); Kay, B.P.; Lee, H.Y.; Marley, S.T. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Nakanishi, T. [Faculty of Chemistry, Institute of Science and Engineering, Kanazawa University (Japan); Pardo, R.C.; Patel, N.; Rehm, K.E. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Robertson, D. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); and others

    2013-01-15

    The extinct p-process nuclide {sup 146}Sm (t{sub 1/2} = 103 {+-} 5 Myr) is known to have been present in the Early-Solar System and has been proposed as an astrophysical chronometer. {sup 146}Sm is also intensely used to date meteorite and planetary differentiation processes, enhancing the importance of an accurate knowledge of the {sup 146}Sm half-life. We are engaged in a new determination of the {sup 146}Sm half-life in which the {sup 146}Sm/{sup 147}Sm atom ratio is determined by accelerator mass spectrometry at the ATLAS facility of Argonne National Laboratory. In order to reduce systematic errors in the AMS determination of the {sup 146}Sm/{sup 147}Sm ratios (in the range of 10{sup -7}-10{sup -9}), {sup 146}Sm and {sup 147}Sm ions were alternately counted in the same detector in the focal plane of a gas-filled magnet, respectively in continuous-wave and attenuated mode. Quantitative attenuation is obtained with the 12 MHz pulsed and ns-bunched ATLAS beam by chopping beam pulses with an RF sweeper in a ratio (digitally determined) down to 1:10{sup 6}. The experiments and preliminary results are discussed.

  11. Arterial injury promotes medial chondrogenesis in Sm22 knockout mice.

    Science.gov (United States)

    Shen, Jianbin; Yang, Maozhou; Jiang, Hong; Ju, Donghong; Zheng, Jian-Pu; Xu, Zhonghui; Liao, Tang-Dong; Li, Li

    2011-04-01

    Expression of SM22 (also known as SM22alpha and transgelin), a vascular smooth muscle cells (VSMCs) marker, is down-regulated in arterial diseases involving medial osteochondrogenesis. We investigated the effect of SM22 deficiency in a mouse artery injury model to determine the role of SM22 in arterial chondrogenesis. Sm22 knockout (Sm22(-/-)) mice developed prominent medial chondrogenesis 2 weeks after carotid denudation as evidenced by the enhanced expression of chondrogenic markers including type II collagen, aggrecan, osteopontin, bone morphogenetic protein 2, and SRY-box containing gene 9 (SOX9). This was concomitant with suppression of VSMC key transcription factor myocardin and of VSMC markers such as SM α-actin and myosin heavy chain. The conversion tendency from myogenesis to chondrogenesis was also observed in primary Sm22(-/-) VSMCs and in a VSMC line after Sm22 knockdown: SM22 deficiency altered VSMC morphology with compromised stress fibre formation and increased actin dynamics. Meanwhile, the expression level of Sox9 mRNA was up-regulated while the mRNA levels of myocardin and VSMC markers were down-regulated, indicating a pro-chondrogenic transcriptional switch in SM22-deficient VSMCs. Furthermore, the increased expression of SOX9 was mediated by enhanced reactive oxygen species production and nuclear factor-κB pathway activation. These findings suggest that disruption of SM22 alters the actin cytoskeleton and promotes chondrogenic conversion of VSMCs.

  12. Kampen om det sibiriske smør

    DEFF Research Database (Denmark)

    Larsen, Inge Marie

    2001-01-01

    Afhandlingen følger opbygningen af og udviklingen i den vestsibiriske smørsektor og den internationale handel med sibirisk smør. Hvordan gik det til, at Rusland blev verdens næststørste smøreksportør? Indfaldsvinkelen er lokal sibirisk, national russisk og global, idet danske og engelske firmaers...

  13. Uzurpacija zemljišta : Land usurpation

    OpenAIRE

    Jusuf Topoljak; Admir Mulahusić

    2011-01-01

    Rad na temu „Uzurpacija zemljišta“ izlaže problematiku uzurpacije zemljišta u Bosni i Hercegovini. Velika je uloga geodezije u rješavanju ovakvog, za društvo kompleksnog problema. U radu su date naznake definisanja i rješavanja problema uzurpiranog zemljišta. : Work on the topic of "land usurpation," exposes the issue of land usurpation in Bosnia and Herzegovina. Geodesy has a very important role in solving such a complex problem for the whole society. In this paper are given hints of defin...

  14. Uzurpacija zemljišta : Land usurpation

    Directory of Open Access Journals (Sweden)

    Jusuf Topoljak

    2011-12-01

    Full Text Available Rad na temu „Uzurpacija zemljišta“ izlaže problematiku uzurpacije zemljišta u Bosni i Hercegovini. Velika je uloga geodezije u rješavanju ovakvog, za društvo kompleksnog problema. U radu su date naznake definisanja i rješavanja problema uzurpiranog zemljišta. : Work on the topic of "land usurpation," exposes the issue of land usurpation in Bosnia and Herzegovina. Geodesy has a very important role in solving such a complex problem for the whole society. In this paper are given hints of defining and solving the problem of land usurpation.

  15. 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.

  16. GdNCT of spontaneous canine melanoma

    International Nuclear Information System (INIS)

    Mitin, V.N.; Kulakov, V.N.; Khokhlov, V.F.

    2006-01-01

    The effectiveness of GdNCT has been studied in dogs with spontaneous melanoma of the mucousmembrane of the oral cavity patients on the NCT base at the IRT MEPhI reactor. The control group with melanomas was treated with neutrons. Fourteen canine patients were selected in the Clinic of Experimental Therapy affiliated with the RCRC RAMS. The calculation of doses has shown that the total dose of energy release depending on Gd concentration in the target can be several times higher than the dose produced by the reactor neutron beam. The calculations were carried out using the diffusion pharmacokinetic model. The gadolinium drug dipentast was administered intratumorally immediately prior to irradiation. The tumor size was estimated by measuring it in three projections. The tumor was irradiated for 60-90 minutes with a thermal neutron flux of 0.7x10 9 n/cm 2 s. The dose on tumor was 80-120 Gy, on surrounding tissues - 12-15 Gy. The treatment plan included immunotherapy with Roncoleikin in a dose of (15-10)x10 3 IE/kg. The results of GdNCT are still under observation. The results conform to those obtained by us earlier in cell cultures and inoculated experimental tumors. GdNCT is also effective in combination with immunotherapy. (author)

  17. Magnetic short range order in Gd

    International Nuclear Information System (INIS)

    Child, H.R.

    1976-01-01

    Quasielastic neutron scattering has been used to investigate magnetic short range order in Gd for 80 0 K 0 K. Short range order exists throughout this range from well below T/sub C/ = 291 0 K to well above it and can be reasonably well described by an anisotropic Orstein-Zernike form for chi

  18. Theoretical Magnon Dispersion Curves for Gd

    DEFF Research Database (Denmark)

    Lindgård, Per-Anker; Harmon, B. N.; Freeman, A. J.

    1975-01-01

    The magnon dispersion curve of Gd metal has been determined from first principles by use of augmented-plane-wave energy bands and wave functions. The exchange matrix elements I(k⃗, k⃗′) between the 4f electrons and the conduction electrons from the first six energy bands were calculated under...

  19. Gd-substituted Bi-2223 superconductor

    Indian Academy of Sciences (India)

    The effects of gadolinium doping at calcium site on the normal and super- conducting properties of Bi-2223 system were ... quantities of the metal oxides and the carbonates were taken and thoroughly mixed. The calcination of the mixture after .... Therefore, Gd has higher solubility in (BiPb)-2223 as compared to Pr, and is, ...

  20. Hyperfine structure in the Gd II spectrum and the nuclear electric quadrupole moment of 157Gd

    International Nuclear Information System (INIS)

    Clieves, H.P.; Steudel, A.

    1979-01-01

    The hyperfine structure of 157 Gd was investigated in 20 Gd II lines by means of a photoelectric recording Fabry-Perot interferometer with digital data processing. The hyperfine splitting factors, A and B, were obtained by computer fits to the observed line structures. Using a multiconfigurational set of wave functions in intermediate coupling derived by Wyart, mono-electronic parameters were deduced by a parametric treatment. The nuclear electric quadrupole moment of 157 Gd was evaluated from the quadrupole interaction of the 5d electron in 4f 7 5d6s, the 5d electron in 4f 7 5d6p, and the 6p electron in 4f 7 5d6p. The three values obtained for the quadrupole moment agree very well. The final result, corrected for Sternheimer shielding, is Q( 157 Gd) = 1.34(7) x 10 -24 cm 2 . (orig.) [de

  1. Measurement of Gd content in (U,Gd)O2 using thermal gravimetric analysis

    International Nuclear Information System (INIS)

    Kim, Keon Sik; Yang, Jae Ho; Kang, Ki Won; Song, Kun Woo; Kim, Gil Moo

    2004-01-01

    We propose a simple and precise method for measuring the Gd content in the (U,Gd)O 2 pellet by only measuring the weight variation of the pellet during thermal heat treatment in air. The (U,Gd)O 2 fuel pellets were oxidized at 475 deg. C, subsequently heat treated at 1300 deg. C, and then cooled to room temperature in air. The accompanying weight variations were measured using thermo gravimetric analysis (TGA). The measured weight variations were mathematically analyzed with reference to the successive phase reactions during the heat treatment. This method provides an advantage in that the rare-earth element content including Gd can be measured using relatively simple equipment such as an electric furnace and a balance

  2. Non-ionic contributions to the electric-field gradient at 111Cd/181Ta impurities in bixbyites

    International Nuclear Information System (INIS)

    Renteria, Mario; Freitag, Kristian; Errico, Leonardo A.

    1999-01-01

    The electric-field-gradient (EFG) tensor at both cation sites of the bixbyite structure in 181 Hf-implanted Lu- and Sm-sesquioxides was determined by the PAC technique. The cumulated EFG data at Ta-impurity sites in binary oxides enable us to discuss the 'universal' character of the empirical correlation between local and ionic contributions to the EFG in these systems. An EFG factorization in terms of the electronic characteristics of the probe and the geometry of the cation coordination is proposed, which explains the experimental EFG results at Ta/Cd impurity sites in bixbyites and agrees with a simplified decomposition of the EFG valence contribution coming from ab-initio calculations

  3. Thermal Behaviour of Sm0.5 R 0.5FeO3 (R = Pr, Nd) Probed by High-Resolution X-ray Synchrotron Powder Diffraction.

    Science.gov (United States)

    Pavlovska, Olena; Vasylechko, Leonid; Buryy, Oleh

    2016-12-01

    Mixed ferrites Sm0.5Pr0.5FeO3 and Sm0.5Nd0.5FeO3 with orthorhombic perovskite structure isotypic with GdFeO3 were synthesized by solid-state reaction technique in air at 1473 K. Structural parameters obtained at room temperature prove a formation of continuous solid solutions in the SmFeO3-PrFeO3 and SmFeO3-NdFeO3 pseudo-binary systems. Sm0.5Pr0.5FeO3 and Sm0.5Nd0.5FeO3 show strongly anisotropic nonlinear thermal expansion: thermal expansion in the b direction is twice lower than in the a and c directions. The average linear thermal expansion coefficients of Sm0.5Pr0.5FeO3 and Sm0.5Nd0.5FeO3 in the temperature range of 298-1173 K are in the limits of (9.0-11.1) × 10(-6) K(-1), which is close to the values reported for the parent RFeO3 compounds. Subtle anomalies in the lattice expansion of Sm0.5Pr0.5FeO3 and Sm0.5Nd0.5FeO3 detected at 650-750 K reflect magnetoelastic coupling at the magnetic ordering temperature T N.

  4. Description and exploitation of benchmarks involving 149Sm, a fission product taking part of the burn up credit in spent fuels

    International Nuclear Information System (INIS)

    Anno, J.; Poullot, G.

    1995-01-01

    Up to now, there was no benchmark to validate the Fission Products (FPs) cross sections in criticality safety calculations. The protection and nuclear safety institute (IPSN) has begun an experimental program on 6 FPs ( 103 Rh, 133 Cs, 143 Nd, 149 Sm, 152 Sm, and 155 Gd daughter of 155 Eu) giving alone a decrease of reactivity equal to half the whole FPs in spent fuels (except Xe and I). Here are presented the experiments with the 149 Sm and the results obtained with the APOLLO I-MORET III calculations codes. 11 experiments are carried out in a zircaloy tank of 3.5 1 containing slightly nitric acid solutions of Samarium (96,9% in weight of 149S m) at 0.1048 -0.2148 - 0.6262 g/l concentrations. It was placed in the middle of arrays of UO 2 rods (4.742 % U5 weight %) at square pitch of 13 mm. The underwater height of the rods is the critical parameter. In addition, 7 experiments were performed with the same apparatus with water and boron proving a good experimental representativeness and a good accuracy of the calculations. As the reactivity worth of the Sm tank is between 2000 and 6000 10 -5 , the benchmarks are well representative and the cumulative absorption ratios show that 149 Sm is well qualified under 1 eV. (authors). 8 refs., 7 figs., 6 tabs

  5. SM-1420 computer conjugation with the ES-5017 magnetic tape storage device and the SM-6313 printer

    International Nuclear Information System (INIS)

    Zhurkin, V.V.; Safonov, A.A.; Troitskij, A.N.

    1987-01-01

    The flow sheets are given and the methods of the technical implementation of expansion units of SM 5002.4 controllers to connect NML ES-5017 and analogue-digital printer ATsPU SM-6818, respectively, to SM-1420 computer are described

  6. Superconductivity at 43K in SmFeAsO1-xFx

    Science.gov (United States)

    Chen, X. H.; Wu, T.; Wu, G.; Liu, R. H.; Chen, H.; Fang, D. F.

    2008-06-01

    Since the discovery of high-transition-temperature (high-Tc) superconductivity in layered copper oxides, extensive effort has been devoted to exploring the origins of this phenomenon. A Tc higher than 40K (about the theoretical maximum predicted from Bardeen-Cooper-Schrieffer theory), however, has been obtained only in the copper oxide superconductors. The highest reported value for non-copper-oxide bulk superconductivity is Tc = 39K in MgB2 (ref. 2). The layered rare-earth metal oxypnictides LnOFeAs (where Ln is La-Nd, Sm and Gd) are now attracting attention following the discovery of superconductivity at 26K in the iron-based LaO1-xFxFeAs (ref. 3). Here we report the discovery of bulk superconductivity in the related compound SmFeAsO1-xFx, which has a ZrCuSiAs-type structure. Resistivity and magnetization measurements reveal a transition temperature as high as 43K. This provides a new material base for studying the origin of high-temperature superconductivity.

  7. Irradiation response of radio-frequency sputtered Al/Gd2O3/p-Si MOS capacitors

    Science.gov (United States)

    Kahraman, A.; Yilmaz, E.

    2017-10-01

    The usage of the Gadolinium oxide (Gd2O3) as sensitive region in the MOS (Metal-Oxide-Semiconductor)-based dosimeters was investigated in the presented study. The Gd2O3 films grown on p-type Si (100) by RF magnetron sputtering were annealed at 800 °C under N2 ambient. The back and front metal contacts were establishes to produce MOS capacitors. The fabricated Gd2O3 MOS capacitors were irradiated in the dose range 0.5-50 Gy by 60Co gamma source. The performed Capacitance-Voltage (C-V) curves of the Gd2O3 MOS capacitors shifted to right side relative to pre-irradiation one. While continuous increments in the oxide trapped charges with increasing in gamma dose were observed, interface trapped charges fluctuated in the studied dose range. However, the variation of the interface trapped charge densities was found in the order of 1011 cm-2 and no significant variation was observed with applied dose. These results confirm that a significant deterioration does not occur in the capacitance during the irradiation. The higher oxide trapped charges compared to interface trapped charges showed that these traps were more responsible for the shift of the C-V curves. The sensitivity and percentage fading after 105 min of the Gd2O3 MOS capacitor were found as 39.7±1.4 mV/Gy and 14.5%, respectively. The devices sensitivity was found to be higher than that of capacitors composed of Er2O3, Sm2O3, La2O3, Al2O3, and SiO2, but, the high fading values is seen as a major problem for these capacitors. Finally, the barrier height was investigated with gamma exposure and the results showed that its value increased with increasing in radiation dose due to possible presence of the acceptor-like interface states.

  8. High spin states in 143Sm

    International Nuclear Information System (INIS)

    Raut, R.; Ganguly, S.; Kshetri, R.; Mukherjee, G.; Mukherjee, A.; Banerjee, P.; Saha Sarkar, M.; Bhattacharya, S.; Goswami, A.; Bhattacharjee, T.; Basu, S.K.; Mukhopadhyaya, S.; Krishichayan; Chakraborty, A.; Gangopadhyay, G.

    2004-01-01

    Large amount of experimental data has been obtained in the recent past on several Nd (Z=60) and Pm (Z=61) isotopes near N=82 shell closure which exhibits an irregular yrast sequence, typical of a non-spherical shape at low spins. The nucleus 143 Sm (Z=62) with a single neutron hole in the N=82 closed shell was investigated as a part of this proposed study

  9. Model SM-1 ballast density gauge

    International Nuclear Information System (INIS)

    Gao Weixiang; Fang Jidong; Zhang Xuejuan; Zhang Reilin; Gao Wanshan

    1990-05-01

    The ballast density is one of the principal parameters for roadbed operating state. It greatly affects the railroad stability, the accumulation of railroad residual deformation and the amount of work for railroad maintenance. SM-1 ballast density gauge is designed to determine the density of ballast by using the effect of γ-ray passed through the ballast. Its fundamentals, construction, specifications, application and economic profit are described

  10. X(5 Symmetry to 152Sm

    Directory of Open Access Journals (Sweden)

    Eid S. A.

    2016-07-01

    Full Text Available The excited positive and negative parity states, potential energy surfaces, V ( ; , electromagnetic transition probabilities, B ( E 1, B ( E 2, electric monopole strength X ( E 0 = E 2 and staggering e ect, I = 1, were calculated successfully using the inter- acting boson approximation model IBA -1. The calculated values are compared to the available experimental data and show reasonable agreement. The energy ratios and contour plot of the potential energy surfaces show that 152 Sm is an X (5 candidate.

  11. A superdeformed band in {sup 142}Sm

    Energy Technology Data Exchange (ETDEWEB)

    Hackman, G; Mullins, J M; Kuehner, J A; Prevost, D; Waddington, J C [McMaster Univ., Hamilton, ON (Canada). Dept. of Physics; Galindo-Uribarri, A; Janzen, V P; Radford, D C; Schmeing, N; Ward, D [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.

    1992-08-01

    Observation of {gamma}-{gamma} coincidences from the reaction {sup 124}Sn({sup 24}Mg,6n){sup 142}Sm at 145 MeV indicates the existence of a rotational band with dynamic moment of inertia J{sup (2)} similar to that of the superdeformed band in the isotone {sup 143}Eu. This result is consistent with calculations predicting superdeformed structures in N = 80, Z {approx} 64 nuclei. (author). 8 refs., 4 figs.

  12. Project Ta-kos Outreach. Final Report.

    Science.gov (United States)

    Askew, Linda; And Others

    The Project Ta-kos Outreach program is an inservice training model designed to increase the probability that children (ages birth to 8) at risk for or with special needs and their families can access and receive appropriate services in order to remain an integral part of the community in which they reside. The program reflects an ecological…

  13. Miks ta nii teeb? / Kristiina Voolaid

    Index Scriptorium Estoniae

    Voolaid, Kristiina

    1999-01-01

    Kuidas mõtleb ruumikujundaja, kui ta valib vorme, värve, materjale ja esemeid? Sisearhitekt Kristiina Voolaid seletab oma mõtteid Kawe Plaza hoones asuvate Hüvitusfondi ja Werol Tehased kontorite ning noorele perekonnale sisustatud vanalinnakorteri näitel

  14. Ordered perovskites with cationic vacancies. 9. Compounds of the type Sr/sub 2/Srsub(1/4)Bsub(1/2)sup(III)vacantsub(1/4)WO/sub 6/ equivalent to Sr/sub 8/SrB/sub 2/sup(III)vacantW/sub 4/O/sub 24/ (Bsup(III) = La, Pr, Nd, Sm - Tm, Y)

    Energy Technology Data Exchange (ETDEWEB)

    Kemmler-Sack, S; Ehmann, A [Tuebingen Univ. (Germany, F.R.). Lehrstuhl fuer Anorganische Chemie 2

    1981-08-01

    The compounds Sr/sub 2/Srsub(1/4)Bsub(1/2)sup(III)vacantsub(1/4)WO/sub 6/ equivalent to Sr/sub 8/SrB/sub 2/sup(III)vacantW/sub 4/O/sub 24/ belong to the group of perovskites with octahedral cationic vacancies (cation/vacancy ratio (CN 6) = 7:1). For the larger Bsup(III) ions (La, Pr, Nd, Sm-Dy) different ordering effects are observed. The perovskites with Bsup(III) = Sm, Eu, Gd are polymorphic too (HT modification: higher ordered cubic perovskite (Bsup(III) = Gd: a = 2 x 8.23/sub 4/ A); LT modification: hexagonal perovskite stacking polytype (Bsup(III) = Gd: a = 9.95/sub 4/ A; c = 19.0/sub 4/ A)). With the smaller Bsup(III) ions (Ho, Er, Tm and Y) a cubic, 1:1 ordered perovskite type is observed.

  15. Calculation of the band structure of GdCo2, GdRh2 e GdIr2 by the APW method

    International Nuclear Information System (INIS)

    Carvalho, J.A.B. de.

    1974-03-01

    The band structure of GdCo 2 , GdRh 2 , GdIr 2 has been calculated by the APW method. A histogram of the density of states is presented for each compound. The bands are transition-metal-like, with s-d hybridization near the Fermi level. The 5d character near the Fermi level increases as one goes from Co to Ir

  16. Electric-field gradients at Ta donor impurities in Cr2O3(Ta) semiconductor

    International Nuclear Information System (INIS)

    Darriba, G.N.; Errico, L.A.; Munoz, E.L; Richard, D.; Eversheim, P.D.; Renteria, M.

    2009-01-01

    We report perturbed-angular-correlation (PAC) experiments on 181 Hf(→ 181 Ta)-implanted corundum Cr 2 O 3 powder samples in order to determine the magnitude and symmetry of the electric-field gradient (EFG) tensor at Ta donor impurity sites of this semiconductor. These results are analyzed in the framework of ab initio full-potential augmented-plane wave plus local orbitals (FP-APW+lo) calculations. The results are also compared with EFG results coming from PAC experiments in isomorphous α-Al 2 O 3 and α-Fe 2 O 3 doped with 111 In→ 111 Cd and 181 Hf→ 181 Ta tracers. This combined analysis enables us to quantify the magnitude of the lattice relaxations induced by the presence of the impurity and to determine the charge state of the impurity donor level introduced by Ta in the band gap of the semiconductor.

  17. CW laser properties of Nd:GdYAG, Nd:LuYAG, and Nd:GdLuAG mixed crystals

    Science.gov (United States)

    Di, J. Q.; Xu, X. D.; Li, D. Z.; Zhou, D. H.; Wu, F.; Zhao, Z. W.; Xu, J.; Tang, D. Y.

    2011-10-01

    Three mixed crystals, Nd:GdYAG, Nd:LuYAG, and Nd:GdLuAG, were grown by Czochralski method. We report the continuous-wave (CW) Nd:GdYAG, Nd:LuYAG, and Nd:GdLuAG laser operation under laser diode pumping. The maximum output powers are 4.11, 5.31, and 7.47 W, with slope efficiency of 73.0, 55.3, and 57.1%, respectively. With replacing Lu3+ or Y3+ ions with large Gd3+ ions, the pump efficiency increases.

  18. Radiochemical separations of target-like reaction products from Au-, Pt-, and Th-targets after irradiation with GeV protons

    International Nuclear Information System (INIS)

    Szweryn, B.; Bruechle, W.; Schausten, B.; Schaedel, M.

    1988-08-01

    Chemical separation procedures for separations of reaction products after spallation reactions with 2.6 GeV protons and heavy element targets are presented. To determine independent cross sections of individual isotopes the elements Au, Pt, Ir, Os, Re, W, Ta, Hf, (Lu, Yb, Tm, Er), (Gd, Eu, Sm), were separated from gold targets, Pt, Ir, Os, W, Ta, Hf, (Lu, Yb, Tm, Er), (Gd, Eu, Sm) from a platinum target and Au, Tl from a thorium target. (orig.)

  19. Structure and physical properties of Cr_5B_3-type Ta_5Si_3 and Ta_5Ge_3

    International Nuclear Information System (INIS)

    Yuan, Fang; Forbes, Scott; Ramachandran, Krishna Kumar; Mozharivskyj, Yurij

    2015-01-01

    The Cr_5B_3-type Ta_5Si_3 phase was prepared by arc-melting, while the Cr_5B_3-type Ta_5Ge_3 one was synthesized through sintering at 1000 °C. X-ray single crystal diffraction was employed to elucidate their structure. According to the magnetization measurements, both Ta_5Si_3 and Ta_5Ge_3 are Pauli paramagnets, with Ta_5Ge_3 showing a Curie-Weiss-like paramagnetic behavior at low temperatures likely due to presence of paramagnetic impurity. Both Ta_5Si_3 and Ta_5Ge_3 display a very low electrical resistivity from 2 to 300 K. The resistivity is constant below 20 K, but displays a positive temperature coefficient above 20 K. Electronic structure calculations with the TB-LMTO-ASA method support the metallic character of the two phases and suggest that the bonding is optimized in both phases. - Highlights: • Synthesis of Cr_5B_3-type Ta_5Si_3 and Ta_5Ge_3 phases with high purity by arc-melting and sintering, respectively. • Magnetization data and electrical resistivity of the Cr_5B_3-type Ta_5Si_3 and Ta_5Ge_3 phases. • Crystal and electronic structure analysis for Ta_5Si_3 and Ta_5Ge_3 phase by X-ray diffraction and TB-LMTO-ASA calculations.

  20. Coercivity Recovery Effect of Sm-Fe-Cu-Al Alloy on Sm2Fe17N3 Magnet

    Science.gov (United States)

    Otogawa, Kohei; Asahi, Toru; Jinno, Miho; Yamaguchi, Wataru; Takagi, Kenta; Kwon, Hansang

    2018-03-01

    The potential of a Sm-Fe-Cu-Al binder for improvement of the magnetic properties of Sm2Fe17N3 was examined. Transmission electron microscope (TEM) observation of a Sm-Fe-Cu-Al alloy-bonded Sm2Fe17N3 magnet which showed high coercivity revealed that the Sm-Fe-Cu-Al alloy had an effect of removing the surface oxide layer of the Sm2 Fe17N3 grains. However, the Sm-Fe-Cu-Al binder was contaminated by carbon and nitrogen, which originated from the organic solvent used as the milling medium during pulverization. To prevent carbon and nitrogen contamination, the Sm-Fe- Cu-Al alloy was added directly on the surface of the Sm2Fe17N3 grains by sputtering. Comparing the recovered coercivity per unit amount of the added binder the uncontaminated binder-coated sample had a higher coercivity recovery effect than the milled binder-added sample. These results suggested that sufficient addition of the contamination-free Sm-Fe-Cu-Al binder has the possibility to reduce the amount of binder necessary to produce a high coercive Sm2Fe17N3 magnet.

  1. Study of fuel element characteristic of SM and SMP (SM-PRIMA) fuel assemblies

    International Nuclear Information System (INIS)

    Klinov, A.V.; Kuprienko, V.A.; Lebedev, V.A.; Makhin, V.M.; Tuchnin, L.M.; Tsykanov, V.A.

    1999-01-01

    The paper discusses the techniques and results of reactor tests and post-reactor investigations of the SM reactor fuel elements and fuel elements developed in the process of designing the specialized PRIMA test reactor with the SM reactor fuel elements used as a prototype and which are referred to as the SMP fuel elements. The behavior of fuel elements under normal operating conditions and under deviation from normal operating conditions was studied to verify the calculation techniques, to check the calculation results during preparation of the SM reactor safety substantiation report and to estimate the possibility of using such fuel elements in other projects. During tests of fuel rods under deviation from normal operating conditions their advantages were shown over fuel elements, the components of which were produced using the Al-based alloys. (author)

  2. Direct observation of effective temperature of Ta atom in layer compound TaS2 by neutron resonance absorption spectrometer

    International Nuclear Information System (INIS)

    Tokuda, Koji; Kamiyama, Takashi; Kiyanagi, Yoshiaki; Moreh, R.; Ikeda, Susumu

    2001-01-01

    A neutron resonance absorption spectrometer, DOG has been installed at KENS, High Energy Accelerator Research Organization Neutron Source, which enables us to investigate the motions of a particular element by analyzing the line width of resonance absorption spectrum. We measured the temperature dependence of the effective temperature of Ta motion in TaS 2 as well as in Ta metal using DOG. The effective temperatures extracted from the observed absorption spectrum agree well with the calculated values from the phonon density of states of Ta metal over a wide temperature range of 10 to 300 K. We also succeeded in measuring both the angular dependence and the temperature dependence of effective temperatures of Ta in a layer compound TaS 2 . Based on the temperature dependence of the effective temperature, the partial phonon density of states of Ta in TaS 2 was discussed. (author)

  3. Acute toxicity of injection of 153Sm-EDTMP

    International Nuclear Information System (INIS)

    Chen Baiwei; Chai Xuehong

    2004-01-01

    Sm-153 has several distinct advantages as a radiopharmaceutical for the treat of patients with bone to skeletal metastasis. Sm-153 shows high skeletal uptake and rapid blood and nonosseous tissue clearance. Several paper have considered the toxicity of 153Sm-EDTMP. We report the acute toxicity in mice and rats after injection of 153Sm-EDTMP or unlabeled EDTMP. The EDTMP was injected to mice by 9.76, 7.8, 6.25, 5, 4 mg/Kg. The logarithmic dose of EDTMP were given to mice to determine LD50. The LD50 of EDTMP in mice is 7.1 mg/Kg. The decay of 153Sm-EDTMP for 4 months were injected to mice at dose of 225 mg/Kg. 153Sm-EDTMP were given at 4 difference dosage to rats by 74 MBq/Kg, 370 MBq/Kg, 1110 MBq/Kg, 1850 MBq/Kg. The LD50 of 153Sm-EDTMP in rats is more than 370 MBq/Kg. Although the cold EDTMP LD50 was low, chelated with Sm can decrease it's toxicity. The decay 153Sm-EDTMP can be safe at dose of 225 mg/Kg. The clinical dose will be used at 37 MBq/Kg. So there is no need to consider to acute toxicity in clinical used 153Sm-EDTMP in designated regimen because the safe range is wide enough to cover clinical used. (authors)

  4. Dielectric spectroscopy of the SmQ* phase

    Science.gov (United States)

    Perkowski, P.; Bubnov, A.; Piecek, W.; Ogrodnik, K.; Hamplová, V.; Kašpar, M.

    2011-11-01

    Liquid crystal possessing two biphenyl moieties in the molecular core and lateral chlorine substitution far from the chiral chain has been studied by dielectric spectroscopy. On cooling from the isotropic phase, the material possesses the frustrated smectic Q* (SmQ*) and SmCA* phases. It has been confirmed by dielectric spectroscopy that the SmQ* phase can be related to the SmCA* anti-ferroelectric phase. However, only one relaxation process has been observed in the SmQ* phase, while in the SmCA*, two relaxations are clearly detectable. It seems that the mode found in the SmQ* can be connected with high-frequency anti-phase mode observed in the SmCA* phase. Its relaxation frequency is similar to PH relaxation frequency, but is weaker. The same relaxation has been observed even a few degrees above the SmQ*-Iso phase transition. Another explanation for the mode detected in SmQ* and isotropic phases can be molecular motions around short molecular axis.

  5. Synthesis and characterization of Gd-doped magnetite nanoparticles

    International Nuclear Information System (INIS)

    Zhang, Honghu; Malik, Vikash; Mallapragada, Surya; Akinc, Mufit

    2017-01-01

    Synthesis of magnetite nanoparticles has attracted increasing interest due to their importance in biomedical and technological applications. Tunable magnetic properties of magnetite nanoparticles to meet specific requirements will greatly expand the spectrum of applications. Tremendous efforts have been devoted to studying and controlling the size, shape and magnetic properties of magnetite nanoparticles. Here we investigate gadolinium (Gd) doping to influence the growth process as well as magnetic properties of magnetite nanocrystals via a simple co-precipitation method under mild conditions in aqueous media. Gd doping was found to affect the growth process leading to synthesis of controllable particle sizes under the conditions tested (0–10 at% Gd"3"+). Typically, undoped and 5 at% Gd-doped magnetite nanoparticles were found to have crystal sizes of about 18 and 44 nm, respectively, supported by X-ray diffraction and transmission electron microscopy. Our results showed that Gd-doped nanoparticles retained the magnetite crystal structure, with Gd"3"+ randomly incorporated in the crystal lattice, probably in the octahedral sites. The composition of 5 at% Gd-doped magnetite was Fe_(_3_−_x_)Gd_xO_4 (x=0.085±0.002), as determined by inductively coupled plasma mass spectrometry. 5 at% Gd-doped nanoparticles exhibited ferrimagnetic properties with small coercivity (~65 Oe) and slightly decreased magnetization at 260 K in contrast to the undoped, superparamagnetic magnetite nanoparticles. Templation by the bacterial biomineralization protein Mms6 did not appear to affect the growth of the Gd-doped magnetite particles synthesized by this method. - Highlights: • Gd-doped magnetite nanoparticles are synthesized via aqueous co-precipitation method under mild conditions. • Gd doping affects growth of magnetite nanoparticles leading to tunable particle size. • Gd-doped magnetite nanoparticles exhibit ferrimagnetic properties.

  6. International collaboration on CESR-TA program

    International Nuclear Information System (INIS)

    Flanagan, John; Suetsugu, Yusuke

    2009-01-01

    An international collaboration on the CESR-TA (Cornell Electron Storage Ring-Test Accelerator) program, which is a program to investigate electron cloud instability (ECI) issues in the positron damping ring of the ILC (International Linear-Collider), is currently underway a Cornell University, KEK is supporting the program through the development of an X-ray beam profile monitor system to measure the extremely small beam size, and through the development of clearing electrodes to mitigate the ECI. (author)

  7. Luminescence properties of the Sm-doped borate glasses

    International Nuclear Information System (INIS)

    Kindrat, I.I.; Padlyak, B.V.; Drzewiecki, A.

    2015-01-01

    The optical absorption and photoluminescence (emission and excitation) spectra as well as decay kinetics of a series of the Sm-doped glasses with Li 2 B 4 O 7 , LiKB 4 O 7 , CaB 4 O 7 , and LiCaBO 3 compositions were investigated and analysed. The Li 2 B 4 O 7 :Sm, LiKB 4 O 7 :Sm, CaB 4 O 7 :Sm, and LiCaBO 3 :Sm glasses of high optical quality have been obtained from the corresponding polycrystalline compounds in the air atmosphere, using a standard glass technology. On the basis of electron paramagnetic resonance (EPR) and optical spectra analysis it was shown that the samarium impurity is incorporated into the glass network as Sm 3+ (4f 5 , 6 H 5/2 ) ions, exclusively. All observed 4f – 4f transitions of the Sm 3+ centres in the optical absorption and luminescence spectra of the investigated glasses are identified. Most intense emission band of the Sm 3+ ions peaked about 598 nm ( 4 G 5/2 → 6 H 7/2 transition) is characterised by a single exponential decay with typical lifetime values, which depend on the basic glass composition as well as concentration and local structure of the Sm 3+ luminescence centres. The quantum efficiency has been evaluated for observed transitions of the Sm 3+ centres using obtained experimental lifetimes and radiative lifetimes calculated by Judd–Ofelt theory. The calculated high quantum efficiencies and measured quantum yields of luminescence show that the investigated borate glasses are perspective luminescence materials. Energy transfer from the Ce 3+ non-controlled impurity and intrinsic luminescence centres to the Sm 3+ centres has been observed. Peculiarities of the Sm 3+ local structure in the network of investigated glasses have been discussed based on the obtained spectroscopic results and structural data. - Highlights: • The Sm-doped Li 2 B 4 O 7 , LiKB 4 O 7 , CaB 4 O 7 , and LiCaBO 3 glasses of high quality were obtained. • EPR, optical absorption and luminescence spectra of Sm 3+ ions in obtained glasses were

  8. SM+Top at the LHC

    CERN Document Server

    McCarthy, Tom; The ATLAS collaboration

    2018-01-01

    This overview talk highlights some of the latest results by the ATLAS, CMS & LHCb collaborations. A particular focus is placed on some of the rarer Standard Model processes which have recently become accessible with the large set of proton-proton collision data collected during the successful second run of the LHC at $\\sqrt{s}$ = 13 TeV. Searches and cross-section measurements involving top quark signatures are given prominence, as well as those targeting highly boosted objects such as SM W/Z and Higgs bosons, and which consequently feature large-R jets and substructure techniques.

  9. Evaluation of Gd and Gd159 as new approaches for cancer treatment

    International Nuclear Information System (INIS)

    Galvao, I.; Neves, M.J.

    2011-01-01

    Metal compounds have shown many biological activities and have been successfully used as anticancer agents such cisplatin. Actually gadolinium (Gd) complexed with a porphyrin Motexafin (MGd) has been investigated as redox-active compound for treatment of cancer. 1 59G d decays by beta emission with an energy of 970 keV and half-life of 18.59 hours. The de-excitation can be via gamma ray and internal conversion electron emission followed by auger electrons and x rays. Considering all of this 1 59G d could be a interesting radionuclide to be as a radio therapeutical agent. The aims of this works were to evaluate the cytotoxicity of Gd and 1 59G d on malignant brain tumors such as glioblastoma multiform, the most frequent brain tumors which has a very poor prognosis. For this purpose, it was used human glioblastoma cell lines T98 (mutant p53) and U87 (wild-type p53) to investigate the cytotoxicity of gadolinium on cell metabolism by MTT assay and also morphological changes, chromatin condensation by DAPI assay and ROS generation. Gadolinium was able to decrease cell viability, the cells presented morphological changes like round shapes and blebs formation after cell treatment with 5x10 -6 M of Gd. Nuclear changing and ROS generation occurred in a dose dependent way indicating the cytotoxic effect of Gd. Treatment with 1 59G d increased all of changes observed with treatment with Gd. These results state for an additive effect of metal toxicity and radioactivity inducing ROS generation as the main mechanism of anti tumoral action of 1 59G d. The results obtained indicated that the radioactive analogues of Gd have increased cytotoxic effects and gadolinium can be a metal of choice for development of new drugs for cancer treatment. (author)

  10. Effect of Al{sub 2}Gd on microstructure and properties of laser clad Mg–Al–Gd coatings

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hong; Zhang, Ke; Yao, Chengwu [Shanghai Key Lab of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Dong, Jie [National Engineering Research Center of Light Alloy Net Forming, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Li, Zhuguo, E-mail: lizg@sjtu.edu.cn [Shanghai Key Lab of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Emmelmann, Claus [Institute of Laser and System Technologies, Hamburg University of Technology, Hamburg, 21073 (Germany)

    2015-03-01

    Highlights: • Mg–Al–Gd coatings with different Gd contents were fabricated by fiber laser cladding. • Chemical compositions and crystal structures of the second phases were characterized. • Dispersion of Al{sub 2}Gd led to further grain refining and elevated mechanical properties. • Al{sub 2}Gd improved high-temperature performances by preventing tiny liquation. - Abstract: In order to investigate the effects of Gd addition on the microstructures and properties of magnesium coatings, the Mg–7.5Al–xGd (x = 0, 2.5, 5.0 and 7.5 wt.%) coatings on cast magnesium alloy were fabricated by laser cladding with wire feeding. The results indicated that the gadolinium (Gd) addition led to the formation of a cubic Al{sub 2}Gd phase as well as suppressed the precipitation of eutectic Mg{sub 17}Al{sub 12} phase. The laser clad coating containing nominally 7.5 wt.% Gd presented the highest microhardness, ultimate tensile strength and yield strength at both room temperature and high temperatures. The enhancement of heat resistant capacities was chiefly attributed to the existence of thermally stable Al{sub 2}Gd particles, which prevented tiny liquation of eutectic phases along the grain boundaries and made great contributions on maintaining high yield ratio during high-temperature deformation.

  11. Effect of Al2Gd on microstructure and properties of laser clad Mg–Al–Gd coatings

    International Nuclear Information System (INIS)

    Chen, Hong; Zhang, Ke; Yao, Chengwu; Dong, Jie; Li, Zhuguo; Emmelmann, Claus

    2015-01-01

    Highlights: • Mg–Al–Gd coatings with different Gd contents were fabricated by fiber laser cladding. • Chemical compositions and crystal structures of the second phases were characterized. • Dispersion of Al 2 Gd led to further grain refining and elevated mechanical properties. • Al 2 Gd improved high-temperature performances by preventing tiny liquation. - Abstract: In order to investigate the effects of Gd addition on the microstructures and properties of magnesium coatings, the Mg–7.5Al–xGd (x = 0, 2.5, 5.0 and 7.5 wt.%) coatings on cast magnesium alloy were fabricated by laser cladding with wire feeding. The results indicated that the gadolinium (Gd) addition led to the formation of a cubic Al 2 Gd phase as well as suppressed the precipitation of eutectic Mg 17 Al 12 phase. The laser clad coating containing nominally 7.5 wt.% Gd presented the highest microhardness, ultimate tensile strength and yield strength at both room temperature and high temperatures. The enhancement of heat resistant capacities was chiefly attributed to the existence of thermally stable Al 2 Gd particles, which prevented tiny liquation of eutectic phases along the grain boundaries and made great contributions on maintaining high yield ratio during high-temperature deformation

  12. Chemical methods for Sm-Nd separation and its application in isotopic geological dating

    International Nuclear Information System (INIS)

    Guo Qifeng.

    1990-01-01

    Three chemical methods for Sm-Nd separation are mainly desribed: low chromatography of butamone-ammonium thiocyanate for hight concentration Sm and Nd separation, P 240 column chromatography for medium concentration Sm-Nd separation, and pressure ion exchange for low concentration Sm-Nd. The first Sm-Nd synchrone obtained in China with Sm-Nd methods is introduced and Sm-Nd isotopic geological dating in Early Archaean rocks in eastern Hebei has been determined

  13. Thin TaC layer produced by ion mixing

    DEFF Research Database (Denmark)

    Barna, Árpád; Kotis, László; Pécz, Béla

    2012-01-01

    in strongly asymmetric ion mixing; the carbon was readily transported to the Ta layer, while the reverse process was much weaker. Because of the asymmetrical transport the C/TaC interface remained sharp independently from the applied fluence. The carbon transported to the Ta layer formed Ta......Ion-beam mixing in C/Ta layered systems was investigated. C 8nm/Ta 12nm and C 20nm/Ta 19nm/C 20nm layer systems were irradiated by Ga+ ions of energy in the range of 2–30keV. In case of the 8nm and 20nm thick C cover layers applying 5–8keV and 20–30keV Ga+ ion energy, respectively resulted...

  14. First-principles study of rare-earth (RE) cobaltites (RE=Nd,Sm,Gd,Dy,Er,Lu)

    Science.gov (United States)

    Topsakal, M.; Wentzcovitch, R. M.

    2014-12-01

    The lanthanide series of the periodic table comprises 15 members ranging from Lanthanum (La) to Lutetium (Lu). Although they are more abundant than silver, and some of them are more abundant than lead, they are known as rare-earth (RE) elements. The "rare" in their name refers to the difficulty of obtaining the pure elements, not to their abundances in nature. They are never found as free metals in the Earth's crust and do not exist as pure minerals. Using first-principles plane-wave calculations, we investigate the structural and electronic properties of rare-earth cobaltites (RECoO3). Structurally consistent Hubbard U treatment was shown to essential for proper description of strongly correlated cobalt-d electrons. We successfully capture the experimentally observed structural trends and give first-principles insights on interesting phenomena related with the cobalt spin state change. It was demonstrated that increase of crystal-field splitting energy between eg-t2g orbitals and shrinking of unoccupied σ*-bonding eg bands are responsible for the increase of onset spin-state transition temperature along the series.

  15. Heat capacity and magnetocaloric effect in polycrystalline Gd 1-xSm xMn 2Si 2

    Science.gov (United States)

    Kumar, Pramod; Singh, Niraj K.; Suresh, K. G.; Nigam, A. K.; Malik, S. K.

    2007-12-01

    We report the magnetocaloric effect in terms of isothermal magnetic entropy change as well as adiabatic temperature change, calculated using the heat capacity data. Using the zero-field heat capacity data, the magnetic contribution to the heat capacity has been estimated. The variations in the magnetocaloric behavior have been explained on the basis of the magnetic structure of these compounds. The refrigerant capacities have also been calculated for these compounds.

  16. Thermal expansion and conductivity of RE2Sn2O7 (RE = La, Nd, Sm, Gd, Er and Yb) pyrochlores

    International Nuclear Information System (INIS)

    Feng, J.; Xiao, B.; Zhou, R.; Pan, W.

    2013-01-01

    Graphical abstract: Calculated cohesive energies and formation enthalpies of RE 2 Sn 2 O 7 compounds. The formation enthalpies at 298 K are more close to the experimental values. -- The calculated cohesive energies and formation enthalpies of Rare earth stannate (RE 2 Sn 2 O 7 ) compounds are in good agreement with the corresponding experimental values. The thermal expansion coefficients (TECs) of rare earth stannates are 7–9 × 10 −6 K −1 at high temperature. The results show that local spin density approximation predicts smaller TECs than the real values. The computed thermal conductivity of RE 2 Sn 2 O 7 is 1.8–2.5 W (m · K) −1 at 1273 K using the Slack–Clarke model, indicating that RE 2 Sn 2 O 7 compounds exhibit good thermal insulating properties at high temperature

  17. A metastable Mg11Sm phase obtained by rapid solidification

    International Nuclear Information System (INIS)

    Budurov, S.

    1993-01-01

    Molten Mg-Sm alloys with a Sm concentration of 4.93, 6.86, and 8.35 at.% were rapidly soldified with the aid of a shock wave gun device. Investigations of the obtained splats were performed with the aid of DSC, X-ray analysis, and metallography. Rapid soldification of the eutectic MgSm 8.35 alloy forms a new Im3m-type phase. (orig.)

  18. Level Lifetime Measurements in ^150Sm

    Science.gov (United States)

    Barton, C. J.; Krücken, R.; Beausang, C. W.; Caprio, M. A.; Casten, R. F.; Cooper, J. R.; Hecht, A. A.; Newman, H.; Novak, J. R.; Pietralla, N.; Wolf, A.; Zyromski, K. E.; Zamfir, N. V.; Börner, H. G.

    2000-10-01

    Shape/phase coexistence and the evolution of structure in the region around ^152Sm have recently been of great interest. Experiments performed at WNSL, Yale University, measured the lifetime of low spin states in a target of ^150Sm with the recoil distance method (RDM) and the Doppler-shift attenuation method (DSAM). The low spin states, both yrast and non-yrast, were populated via Coulomb excitation with a beam of ^16O. The experiments were performed with the NYPD plunger in conjunction with the SPEEDY γ-ray array. The SCARY array of solar cells was used to detect backward scattered projectiles, selecting forward flying Coulomb excited target nuclei. The measured lifetimes yield, for example, B(E2) values for transitions such as the 2^+2 arrow 2^+1 and the 2^+3 arrow 0^+_1. Data from the RDM measurment and the DSAM experiment will be presented. This work was supported by the US DOE under grants DE-FG02-91ER-40609 and DE-FG02-88ER-40417.

  19. Magnetic properties of Sm-based filled skutterudite phosphides

    Energy Technology Data Exchange (ETDEWEB)

    Giri, R.; Sekine, C.; Shimaya, Y.; Shirotani, I.; Matsuhira, K.; Doi, Y.; Hinatsu, Y.; Yokoyama, M.; Amitsuka, H

    2003-05-01

    Filled skutterudites SmFe{sub 4}P{sub 12} and SmOs{sub 4}P{sub 12} have been prepared at high temperature and high pressure. The temperature dependence of electrical resistivity in both compounds shows metallic behavior. The magnetic susceptibility and specific heat measurements indicate that SmFe{sub 4}P{sub 12} shows a ferromagnetic ordering at 1.5 K, whereas SmOs{sub 4}P{sub 12} is an antiferromagnet with a T{sub N} of 4.6 K.

  20. Anomalous Hall effect in Fe/Gd bilayers

    KAUST Repository

    Xu, W. J.; Zhang, Bei; Liu, Z. X.; Wang, Z.; Li, W.; Wu, Z. B.; Yu, R. H.; Zhang, Xixiang

    2010-01-01

    Non-monotonic dependence of anomalous Hall resistivity on temperature and magnetization, including a sign change, was observed in Fe/Gd bilayers. To understand the intriguing observations, we fabricated the Fe/Gd bilayers and single layers of Fe and Gd simultaneously. The temperature and field dependences of longitudinal resistivity, Hall resistivity and magnetization in these films have also been carefully measured. The analysis of these data reveals that these intriguing features are due to the opposite signs of Hall resistivity/or spin polarization and different Curie temperatures of Fe and Gd single-layer films. Copyright (C) EPLA, 2010

  1. Anomalous Hall effect in Fe/Gd bilayers

    KAUST Repository

    Xu, W. J.

    2010-04-01

    Non-monotonic dependence of anomalous Hall resistivity on temperature and magnetization, including a sign change, was observed in Fe/Gd bilayers. To understand the intriguing observations, we fabricated the Fe/Gd bilayers and single layers of Fe and Gd simultaneously. The temperature and field dependences of longitudinal resistivity, Hall resistivity and magnetization in these films have also been carefully measured. The analysis of these data reveals that these intriguing features are due to the opposite signs of Hall resistivity/or spin polarization and different Curie temperatures of Fe and Gd single-layer films. Copyright (C) EPLA, 2010

  2. Evaluation of the exothermicity of the chemi-ionization reaction Sm + O → SmO+ + e−

    International Nuclear Information System (INIS)

    Cox, Richard M; Kim, JungSoo; Armentrout, P. B.; Bartlett, Joshua; VanGundy, Robert A.; Heaven, Michael C.; Ard, Shaun G.; Shuman, Nicholas S.; Viggiano, Albert A.; Melko, Joshua J.

    2015-01-01

    The exothermicity of the chemi-ionization reaction Sm + O → SmO + + e − has been re-evaluated through the combination of several experimental methods. The thermal reactivity (300–650 K) of Sm + and SmO + with a range of species measured using a selected ion flow tube-mass spectrometer apparatus is reported and provides limits for the bond strength of SmO + , 5.661 eV ≤ D 0 (Sm + -O) ≤ 6.500 eV. A more precise value is measured to be 5.72 5 ± 0.07 eV, bracketed by the observed reactivity of Sm + and SmO + with several species using a guided ion beam tandem mass spectrometer (GIBMS). Combined with the established Sm ionization energy (IE), this value indicates an exothermicity of the title reaction of 0.08 ± 0.07 eV, ∼0.2 eV smaller than previous determinations. In addition, the ionization energy of SmO has been measured by resonantly enhanced two-photon ionization and pulsed-field ionization zero kinetic energy photoelectron spectroscopy to be 5.7427 ± 0.0006 eV, significantly higher than the literature value. Combined with literature bond energies of SmO, this value indicates an exothermicity of the title reaction of 0.14 ± 0.17 eV, independent from and in agreement with the GIBMS result presented here. The evaluated thermochemistry also suggests that D 0 (SmO) = 5.83 ± 0.07 eV, consistent with but more precise than the literature values. Implications of these results for interpretation of chemical release experiments in the thermosphere are discussed

  3. Phase-Transition and Magnetic Moment of the Gd3+ Ion in the Gd2Fe17 Compound

    Institute of Scientific and Technical Information of China (English)

    HAO Yan-Ming; FU Bin; ZHOU Yan; ZHAO Miao

    2009-01-01

    The structure and magnetic phase transitions of the Gd2Fe17 compound are investigated by using a differential thermal/thermogravimetric analyzer, x-ray diffraction, and magnetization measurements. The result shows that there are two phase structures for the Gd2Fe17 compound: the hexagonal Th2Ni17-type structure at high tem-peratures (above 1243℃), and the rhombohedrai Th2Zn17-type structure, respectively. A method to measure the magnetic moments of the Gd-sublattice and the Fe-sublattice in the Gd2Fe17 compound is presented. The moments of the Gd-sublattice and the Fe-sublattice in the Gd2Fe17 compound from 77 to 500 K are measured in this way with a vibrating sample magnetometer. A detailed discussion is presented.

  4. 75 FR 43556 - TA-W-73,381, MT Rail Link, Inc., Missoula, MT; TA-W-73,381A, Billings, MT; TA-W-73,381B, Laurel...

    Science.gov (United States)

    2010-07-26

    ... DEPARTMENT OF LABOR Employment and Training Administration TA-W-73,381, MT Rail Link, Inc., Missoula, MT; TA-W-73,381A, Billings, MT; TA-W-73,381B, Laurel, MT; TA-W-73,381C, Livingston, MT; TA-W-73... Helena, Montana. The amended notice applicable to TA-W-73,381 is hereby issued as follows: All workers of...

  5. SmBaCoCuO5+x as cathode material based on GDC electrolyte for intermediate-temperature solid oxide fuel cells

    International Nuclear Information System (INIS)

    Lue Shiquan; Long, Guohui; Ji Yuan; Meng Xiangwei; Zhao Hongyuan; Sun Cuicui

    2011-01-01

    Research highlights: → We synthesize a new kind of layered perovskite SmBaCoCuO 5+x (SBCCO) as a cathode material of a solid oxide fuel cell. → There are some reports on the performance of cathodes in proton-conducting SOFCs based on BaCe 0.8 Sm 0.2 O 3-δ electrolyte. → However, to the best of our knowledge, the performance of SBCCO cathodes in oxygen-ion conducting SOFCs has not been reported to date. → In this work, the ceramic powder SBCCO is examined as a cathode for IT-SOFCs based on Ce 0.9 Gd 0.1 O 1.95 (GDC) electrolyte. - Abstract: The performance of SmBaCoCuO 5+x (SBCCO) cathode has been investigated for their potential utilization in intermediate-temperature solid oxide fuel cells (IT-SOFCs). The powder X-ray diffraction (XRD), thermal expansion and electrochemical performance on Ce 0.9 Gd 0.1 O 1.95 (GDC) electrolyte are evaluated. XRD results show that there is no chemical reaction between SBCCO cathode and GDC electrolyte when the temperature is below 950 o C. The thermal expansion coefficient (TEC) value of SBCCO is 15.53 x 10 -6 K -1 , which is ∼23% lower than the TEC of the SmBaCo 2 O 5+x (SBCO) sample. The electrochemical impedance spectra reveals that SBCCO symmetrical half-cells by sintering at 950 deg. C has the best electrochemical performance and the area specific resistance (ASR) of SBCCO cathode is as low as 0.086 Ω cm 2 at 800 o C. An electrolyte-supported fuel cell generates good performance with the maximum power density of 517 mW cm -2 at 800 deg. C in H 2 . Preliminary results indicate that SBCCO is promising as a cathode for IT-SOFCs.

  6. Probing metastable Sm2+ and optically stimulated tunnelling emission in YPO4: Ce, Sm

    DEFF Research Database (Denmark)

    Prasad, Amit Kumar; Kook, Myung Ho; Jain, Mayank

    2017-01-01

    When the model dosimetry system YPO4: Ce3+, Sm3+ is exposed to X-rays, the charge state of the dopants changes, becoming Ce4+ and Sm2+ via hole and electron trapping, respectively which are metastable; the original charge states can be achieved through electron transfer back from Sm2+ to Ce4+ via......) and its temperature dependence to provide insights into thermal quenching, and c) the kinetics of localised recombination from Sm2+ to Ce4+ on nanoseconds to seconds time scales using sub-band-edge excitation....

  7. Magnetocaloric effect and transport properties of Gd5Ge2(Si1-x Sn x )2 (x=0.23 and 0.40) compounds

    International Nuclear Information System (INIS)

    Campoy, J.C.P.; Plaza, E.J.R.; Nascimento, F.C.; Coelho, A.A.; Pereira, M.C.; Fabris, J.D.; Raposo, M.T.; Cardoso, L.P.; Persiano, A.I.C.; Gama, S.

    2007-01-01

    We report a study about the structural properties of polycrystalline samples of nominal composition Gd 5 Ge 2 (Si 1- x Sn x ) 2 (x=0.23, 0.40) that closely influence their physical behavior particularly related to electric resistivity and magnetocaloric (MCE) effect. The samples were characterized by X-ray diffraction (XRD) using the Rietveld refinement method, metallographic analyses, 119 Sn Moessbauer spectroscopy, DC magnetization and electrical transport measurements. It was identified a Gd 5 Si 2 Ge 2 -monoclinic phase for x=0.23 and a Sm 5 Sn 4 -orthorhombic phase (type II) for x=0.40, both with two non-equivalent crystallographic sites for the Sn ions. We were able to infer on the role of tin on the magnetic and transport properties in these compounds

  8. Energy-beam processing studies on Ta/U and Ir/Ta systems

    International Nuclear Information System (INIS)

    Kaufmann, E.N.; Peercy, P.S.; Jacobson, D.C.; Draper, C.W.; Huegel, F.J.; Echer, C.J.; Makowiecki, D.M.; Balser, J.D.

    1983-01-01

    Films of Ta metal on uranium and of Ir metal on tantalum have been irradiated and melted by pulses from Q-switched Ruby and frequency-doubled Nd:YAG lasers to investigate the nature of the resulting mixtures in light of the very different binary-phase diagrams of the two systems. In addition, a two-phase Ir-Ta alloy has been surface-processed with CW CO 2 -laser radiation and with an electron beam in order to study microstructure refinement and test the advantage of using alloys as opposed to film-on-substrate combinations for the development of claddings

  9. Half Life Measurements in 155Gd

    International Nuclear Information System (INIS)

    Malmskog, S.G.

    1966-08-01

    In the literature there exists a definite difference for the half life of the 86.5 keV level in Gd depending on whether 155 Eu or 155 Tb sources have been used. Using a good energy resolution electron-electron coincidence spectrometer and a 155 Eu source, a half life of 6.48 ± 0.26 nsec was obtained for the 86.5 keV level. This is in agreement with the values previously measured with 155 Tb sources. The half life of the 105.4 keV level was measured to be 1.12 ± 0.05 nsec

  10. Half Life Measurements in {sup 155}Gd

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G

    1966-08-15

    In the literature there exists a definite difference for the half life of the 86.5 keV level in Gd depending on whether {sup 155}Eu or {sup 155}Tb sources have been used. Using a good energy resolution electron-electron coincidence spectrometer and a {sup 155}Eu source, a half life of 6.48 {+-} 0.26 nsec was obtained for the 86.5 keV level. This is in agreement with the values previously measured with {sup 155}Tb sources. The half life of the 105.4 keV level was measured to be 1.12 {+-} 0.05 nsec.

  11. 78 FR 28627 - TA-W-80,340; TA-W-80,340A; TA-W-80,340B

    Science.gov (United States)

    2013-05-15

    ...] Bush Industries, Inc., Mason Drive Facility, Including On-Site Leased Workers From Morris Security...., Mason Drive Facility, Jamestown, New York (TA-W-80,340) and Bush Industries, Inc., Allen Street Facility... applicable to TA-W-80,340 is hereby issued as follows: All workers of Bush Industries, Inc., Mason Drive...

  12. A comparison of Gd-BOPTA and Gd-DOTA for contrast-enhanced MRI of intracranial tumours

    International Nuclear Information System (INIS)

    Colosimo, C.; Knopp, M.V.; Barreau, X.; Gerardin, E.; Kirchin, M.A.; Guezenoc, F.; Lodemann, K.P.

    2004-01-01

    A two-centre intra-individual crossover study was performed in 23 patients with suspected high-grade glioma or metastases to assess and compare the safety and enhancement characteristics of two different MRI contrast media (gadobenate dimeglumine, Gd-BOPTA and gadoterate meglumine, Gd-DOTA) at equivalent doses of 0.1 mmol/kg body weight. T1-weighted spin-echo (SE) and T2-weighted fast SE images were obtained before and T1-weighted images 0, 2, 4, 6, 8 and 15 min after injection. T1-weighted images with magnetisation transfer contrast were acquired 12 min after injection. Qualitative assessment by blinded, off-site readers (reader 1: 19 patients; reader 2: 21) and on-site investigators (23) revealed significant (P ≤0.005) overall preference for Gd-BOPTA over Gd-DOTA for contrast enhancement (Gd-BOPTA preferred in 18, 15 and 18 cases; Gd-DOTA in 0, 1 and 1 and no preference in 1, 5 and 4; off-site readers 1 and 2, and on-site investigators, respectively). A similar significant preference for Gd-BOPTA was expressed by off-site readers and on-site investigators for lesion-to-brain contrast, lesion delineation, internal lesion structure, and overall image preference. Quantitative assessment by off-site readers revealed significantly (p<0.05) greater lesion enhancement with Gd-BOPTA than with Gd-DOTA at all times from 2 min after injection. (orig.)

  13. The effect of Gd doping on the electrical and photoelectrical properties of Gd:ZnO/p-Si heterojunctions

    Energy Technology Data Exchange (ETDEWEB)

    Baturay, Silan [Department of Physics, Faculty of Science, Dicle University, 21280 Diyarbakir (Turkey); Ocak, Yusuf Selim, E-mail: yusufselim@gmail.com [Department of Science, Faculty of Education, Dicle University, 21280 Diyarbakir (Turkey); Science and Technology Application and Research Center, Dicle University, 21280 Diyarbakir (Turkey); Kaya, Derya [Department of Physics, Institute of Natural Applied Sciences, Dicle University, 21280 Diyarbakir (Turkey)

    2015-10-05

    Highlights: • Undoped and Gd doped ZnO thin films were deposited onto p-Si semiconductor. • The Gd:ZnO/p-Si heterojunctions were compared with undoped ZnO/p-Si heterojunction. • A strong effect of Gd doping on the performance of the devices were reported. - Abstract: Undoped ZnO thin films, as well as 1%, 3% and 5% Gd-doped ZnO films, were deposited on p-type Si using spin coating. The structural properties of these thin films were analysed using X-ray diffraction, and the current–voltage (I–V) and capacitance–voltage (C–V) characteristics of the Gd:ZnO/p-Si heterojunctions were compared with those of the undoped ZnO/p-Si heterojunctions. We found that Gd doping had a strong effect on the performance of the devices, and that the Gd:ZnO/p-Si heterojunctions formed with 1% Gd-doped ZnO were the most strongly rectifying, and had the highest barrier height and the lowest series resistance. Furthermore, the I–V measurements of the 1% Gd-doped ZnO/p-Si heterojunction exhibited the strongest response to light.

  14. Limited Range Sesame EOS for Ta

    Energy Technology Data Exchange (ETDEWEB)

    Greeff, Carl William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Crockett, Scott [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rudin, Sven Peter [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Burakovsky, Leonid [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-30

    A new Sesame EOS table for Ta has been released for testing. It is a limited range table covering T ≤ 26, 000 K and ρ ≤ 37.53 g/cc. The EOS is based on earlier analysis using DFT phonon calculations to infer the cold pressure from the Hugoniot. The cold curve has been extended into compression using new DFT calculations. The present EOS covers expansion into the gas phase. It is a multi-phase EOS with distinct liquid and solid phases. A cold shear modulus table (431) is included. This is based on an analytic interpolation of DFT calculations.

  15. Measurement of recoil nuclei of Ta photofission

    International Nuclear Information System (INIS)

    Amroyan, K.A.; Barsegyan, S.A.; Demekhina, N.A.

    1993-01-01

    The results of measuring the characteristics of nuclei leaving the Ta target bombarded by 4,5 GeV bremsstrahlung photons are presented. The thick-target-trap technique is used. The radioactive residual nuclei were detected by the induced activity with the help of the Ge(Li) detector. The forward-backward nucleus ratio is measured, and the kinematical characteristics are calculated in the framework of the two-step vector model of velocities. The data analysis and systematization is carried out in comparison with the results of hardon-nuclear interactions

  16. TA-2 Water Boiler Reactor Decommissioning Project

    International Nuclear Information System (INIS)

    Durbin, M.E.; Montoya, G.M.

    1991-06-01

    This final report addresses the Phase 2 decommissioning of the Water Boiler Reactor, biological shield, other components within the biological shield, and piping pits in the floor of the reactor building. External structures and underground piping associated with the gaseous effluent (stack) line from Technical Area 2 (TA-2) Water Boiler Reactor were removed in 1985--1986 as Phase 1 of reactor decommissioning. The cost of Phase 2 was approximately $623K. The decommissioning operation produced 173 m 3 of low-level solid radioactive waste and 35 m 3 of mixed waste. 15 refs., 25 figs., 3 tabs

  17. Synthesis and Characterization of Hollow Magnetic Alloy (GdNi2, Co5Gd Nanospheres Coated with Gd2O3

    Directory of Open Access Journals (Sweden)

    Wang Li

    2014-01-01

    Full Text Available Uniform magnetic hollow nanospheres (GdNi2, Co5Gd coated with Gd2O3 have been successfully prepared on a large scale via a urea-based homogeneous precipitation method using silica (SiO2 spheres as sacrificed templates, followed by subsequent heat treatment. Nitrogen sorption measurements and scanning electron microscope reveal that these hollow-structured magnetic nanospheres have the mesoporous shells that are composed of a large amount of uniform nanoparticles. After reduction treatment, these nanoparticles exhibit superparamagnetism that might have potential applications in medicine. Furthermore, the developed synthesis route may provide an important guidance for the preparation of other multifunctional hollow spherical materials.

  18. Symmetries for SM Alignment in multi-Higgs Doublet Models

    CERN Document Server

    Pilaftsis, Apostolos

    2016-01-01

    We derive the complete set of maximal symmetries for Standard Model (SM) alignment that may occur in the tree-level scalar potential of multi-Higgs Doublet Models, with $n > 2$ Higgs doublets. Our results generalize the symmetries of SM alignment, without decoupling of large mass scales or fine-tuning, previously obtained in the context of two-Higgs Doublet Models.

  19. Interaction mode between methylene blue-Sm(III) complex and ...

    African Journals Online (AJOL)

    Spectroscopic and viscosity methods were applied to investigate the interaction between methylene blue (MB)-Sm(III) complex and herring sperm DNA by using acridine orange as a spectral probe in Tris-HCl buffer (pH 7.40). By means of molar ratio method, the binding ratios between MB-Sm(III)and DNA were determined ...

  20. Nanocrystallization in Cu-Zr-Al-Sm Bulk Metallic Glasses

    Science.gov (United States)

    Sikan, Fatih; Yasar, Bengisu; Kalay, Ilkay

    2018-04-01

    The effect of rare-earth element (Sm) microalloying on the thermal stability and crystallization kinetics of melt-spun ribbons and suction-cast rods of Zr48Cu38.4Al9.6Sm4 alloy were investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy (TEM), and atom probe tomography (APT). The XRD results of constant heating rate annealing indicated that amorphous Zr48Cu38.4Al9.6Sm4 melt-spun ribbons devitrifies into Cu2Sm at 673 K (400 °C). The sequence continues with the precipitation of Cu10Zr7 and then these two phases coexist. XRD and TEM studies on 1 mm diameter as suction-cast rods indicated the precipitation of 30-nm-mean size Cu2Sm crystals during solidification. TEM investigation of the isothermal crystallization sequence of melt-spun ribbons and 1-mm-diameter suction-cast rods revealed the precipitation of Cu2Sm nanocrystals at the onset of crystallization and the restriction of the growth of these nanocrystals up to 10 nm diameter with further annealing. APT analysis of 1-mm-diameter suction-cast rods showed that the limited growth of Cu2Sm nanocrystals is due to sluggish diffusion of Sm and Al-Zr pile up at the interface.

  1. Alleviating polarity-conflict at the heterointerfaces of KTaO3/GdScO3 polar complex-oxides

    International Nuclear Information System (INIS)

    Thompson, J.; Nichols, J.; Connell, J. G.; Seo, S. S. A.; Hwang, J.; Stemmer, S.

    2014-01-01

    We have synthesized and investigated the heterointerfaces of KTaO 3 (KTO) and GdScO 3 (GSO), which are both polar complex-oxides along the pseudo-cubic [001] direction. Since their layers have the same, conflicting net charges at interfaces, i.e., KO(−1)/ScO 2 (−1) or TaO 2 (+1)/GdO(+1), forming the heterointerface of KTO/GSO should be forbidden due to strong Coulomb repulsion, the so-called polarity conflict. However, we have discovered that atomic reconstruction occurs at the heterointerfaces between KTO thin-films and GSO substrates, which effectively alleviates the polarity conflict without destroying the hetero-epitaxy. Our result demonstrates one of the important ways to create artificial heterostructures from polar complex-oxides.

  2. Oxidative addition of diphenyl disulfide across a Ta=Ta bond. Preparation and characterization of [TaCl3(Me2S)]2(μ-SPh)2

    International Nuclear Information System (INIS)

    Campbell, G.C.; Canich, J.A.M; Cotton, F.A.; Duraj, S.A.; Haw, J.F.

    1986-01-01

    The tantalum complex (SMe 2 )Cl 2 Ta(μ-Cl) 2 (μ-SMe 2 )TaCl 2 (SMe 2 ), possessing a sigma 2 π 2 Ta=Ta double bond, reacts readily with PhSSPh to give (SMe 2 )Cl 3 Ta(μ-SPh) 2 TaCl 2 (SMe 2 ). In this reaction, the starting material loses the bridging SMe 2 ligand and two chloride bridges are broken while only two new SPh bridges are formed in the final product. This oxidative-addition reaction of the S-S single bond to the Ta=Ta double bond converts the face-sharing bioctahedron structure of the starting compound to an edge-sharing bioctahedron structure in the final dimer, with concomitant change of the oxidation state of tantalum from III to IV. The product is the first example of a d 1 -d 1 ditantalum thiolate-bridged dimer. Important structural data for (SMe 2 )Cl 3 Ta(μ-SPh) 2 TaCl 3 (SMe 2 ), which has an inversion center, are determined. The new compound crystallizes in the monoclinic space group C2/c with a = 17.934 (5) A, b = 12.445 (4) A, c = 11.705 (4) A, β = 92.50 (3) 0 , V = 2610 (2) A 3 , and Z = 4. Solid-state 13 C NMR spectroscopy with cross polarization and magic-angle spinning (CP/MAS) at 28 and -103 0 C provides evidence that this compound is diamagnetic. 12 references, 3 figures, 4 tables

  3. Social shaping of technology in TA and HTA

    DEFF Research Database (Denmark)

    Clausen, Christian; Yoshinaka, Yutaka

    2004-01-01

    The paper discusses how the social shaping of technology (SST) approach may be useful in understanding the role played by technology assessment within the context of technological development and change. It is proposed that an SST perspective on TA (or HTA) yields particular insight, regardless...... of whether or not the TA activity bases itself on a social shaping understanding of technology. This is because SST addresses the socially negotiated character of technological development, where TA itself may be construed as an element influencing the process of such negotiation. At the same time, TA...... is a construction, that is, itself a product of negotiations involving social actors. Thus, an understanding that TA is socially shaped, and is involved in the shaping of technology, opens up for a perspective on TA as both entailing constraints and enablements within the context of the particular agenda...

  4. Structural and Magnetic Properties of Sm Implanted GaN

    International Nuclear Information System (INIS)

    Li-Juan, Jiang; Xiao-Liang, Wang; Hong-Ling, Xiao; Zhan-Guo, Wang; Chun, Feng; Ming-Lan, Zhang; Jian, Tang

    2009-01-01

    The structural and magnetic properties of Sm ion-implanted GaN with different Sm concentrations are investigated. XRD results do not show any peaks associated with second phase formation. Magnetic investigations performed by superconducting quantum interference device reveal ferromagnetic behavior with an ordering temperature above room temperature in all the implanted samples, while the effective magnetic moment per Sm obtained from saturation magnetization gives a much higher value than the atomic moment of Sm. These results could be explained by the phenomenological model proposed by Dhar et al. [Phys. Rev. Lett. 94(2005)037205, Phys. Rev. B 72(2005)245203] in terms of a long-range spin polarization of the GaN matrix by the Sm atoms. (condensed matter: electronicstructure, electrical, magnetic, and opticalproperties)

  5. Microstructure and superplasticity of TA15 alloy

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Q.J., E-mail: cruzesun@nchu.edu.cn; Wang, G.C.

    2014-06-01

    Superplasticity of TA15 alloy was investigated by constant strain rate tensile method in this work. In order to enhance superplasticity, thermo-mechanical techniques were applied for refining the grains of the alloy first. The superplastic tensile tests were carried out on a SANS CMT4104 electronic tensile testing machine at temperatures ranging from 780 to 950 °C and strain rates from 3.3×10{sup −4} to 1.1×10{sup −2} s{sup −1}. The tensile elongation-to-failure values between 188% and 1074% were obtained. Microstructure evolution after superplastic deformation was also analyzed by optical microscope (OM) and transmission electron microscope (TEM). The micrographs show that the grains were coarsened after deformation, and α→β phase transformation took place at 950 °C, which resulted in the worst superplasticity. Extensive strain hardening stages were observed in the true stress–strain curves due to high dense dislocations in the thermo-mechanically processed alloy and dynamic grain growth during superplastic deformation. The strain rate sensitivity m and the activation energy values at various deformation conditions were calculated, respectively. Based on an analysis of the above studies, it may be inferred that grain boundary sliding (GBS) in TA15 alloy is accommodated by grain boundary diffusion at high temperatures and low strain rates, and the accommodation process involves dislocation glide creep at low temperatures and high strain rates.

  6. Accident selection methodology for TA-55 FSAR

    International Nuclear Information System (INIS)

    Letellier, B.C.; Pan, P.Y.; Sasser, M.K.

    1995-01-01

    In the past, the selection of representative accidents for refined analysis from the numerous scenarios identified in hazards analyses (HAs) has involved significant judgment and has been difficult to defend. As part of upgrading the Final Safety Analysis Report (FSAR) for the TA-55 plutonium facility at the Los Alamos National Laboratory, an accident selection process was developed that is mostly mechanical and reproducible in nature and fulfills the requirements of the Department of Energy (DOE) Standard 3009 and DOE Order 5480.23. Among the objectives specified by this guidance are the requirements that accident screening (1) consider accidents during normal and abnormal operating conditions, (2) consider both design basis and beyond design basis accidents, (3) characterize accidents by category (operational, natural phenomena, etc.) and by type (spill, explosion, fire, etc.), and (4) identify accidents that bound all foreseeable accident types. The accident selection process described here in the context of the TA-55 FSAR is applicable to all types of DOE facilities

  7. Total neutron cross section for 181Ta

    Directory of Open Access Journals (Sweden)

    Schilling K.-D.

    2010-10-01

    Full Text Available The neutron time of flight facility nELBE, produces fast neutrons in the energy range from 0.1 MeV to 10 MeV by impinging a pulsed relativistic electron beam on a liquid lead circuit [1]. The short beam pulses (∼10 ps and a small radiator volume give an energy resolution better than 1% at 1 MeV using a short flight path of about 6 m, for neutron TOF measurements. The present neutron source provides 2 ⋅ 104  n/cm2s at the target position using an electron charge of 77 pC and 100 kHz pulse repetition rate. This neutron intensity enables to measure neutron total cross section with a 2%–5% statistical uncertainty within a few days. In February 2008, neutron radiator, plastic detector [2] and data acquisition system were tested by measurements of the neutron total cross section for 181Ta and 27Al. Measurement of 181Ta was chosen because lack of high quality data in an anergy region below 700 keV. The total neutron cross – section for 27Al was measured as a control target, since there exists data for 27Al with high resolution and low statistical error [3].

  8. Enhanced room temperature multiferroicity in Gd doped BFO

    CSIR Research Space (South Africa)

    Pradhan, SK

    2009-01-01

    Full Text Available deficient Gd doped multiferroic BFO system. At particular doping level of Gd, this bulk ceramics showed spectacular M~H behavior at room temperature which is likely to open a new avenue for the potential applications in information storing technology as well...

  9. The magnetic anisotropy of Gd-Y alloys

    Science.gov (United States)

    Phu Thuy, Nguyen; Verdonk, H. J.; Menovsky, A.; Franse, J. J. M.; Gersdorf, R.

    1983-02-01

    Magnetic torque curves on single crystals of Gd 1- xY x ( x ⩽ 0.1) show a reduction of the anomalous contribution that was observed in pure Gd, with increasing Y-content. Several explanations of this phenomenon are indicated in this paper.

  10. The Protein Kinase SmSnRK2.6 Positively Regulates Phenolic Acid Biosynthesis in Salvia miltiorrhiza by Interacting with SmAREB1.

    Science.gov (United States)

    Jia, Yanyan; Bai, Zhenqing; Pei, Tianlin; Ding, Kai; Liang, Zongsuo; Gong, Yuehua

    2017-01-01

    Subclass III members of the sucrose non-fermenting-1-related protein kinase 2 (SnRK2) play essential roles in both the abscisic acid signaling and abiotic stress responses of plants by phosphorylating the downstream ABA-responsive element (ABRE)-binding proteins (AREB/ABFs). This comprehensive study investigated the function of new candidate genes, namely SmSnRK2.3 , SmSnRK2.6 , and SmAREB1 , with a view to breeding novel varieties of Salvia miltiorrhiza with improved stress tolerance stresses and more content of bioactive ingredients. Exogenous ABA strongly induced the expression of these genes. PlantCARE predicted several hormones and stress response cis -elements in their promoters. SmSnRK2.6 and SmAREB1 showed the highest expression levels in the leaves of S. miltiorrhiza seedlings, while SmSnRK2.3 exhibited a steady expression in their roots, stems, and leaves. A subcellular localization assay revealed that both SmSnRK2.3 and SmSnRK2.6 were located in the cell membrane, cytoplasm, and nucleus, whereas SmAREB1 was exclusive to the nucleus. Overexpressing SmSnRK2.3 did not significantly promote the accumulation of rosmarinic acid (RA) and salvianolic acid B (Sal B) in the transgenic S. miltiorrhiza hairy roots. However, overexpressing SmSnRK2.6 and SmAREB1 increased the contents of RA and Sal B, and regulated the expression levels of structural genes participating in the phenolic acid-branched and side-branched pathways, including SmPAL1 , SmC4H , Sm4CL1 , SmTAT , SmHPPR , SmRAS , SmCHS , SmCCR , SmCOMT , and SmHPPD . Furthermore, SmSnRK2.3 and SmSnRK2.6 interacted physically with SmAREB1. In summary, our results indicate that SmSnRK2.6 is involved in stress responses and can regulate structural gene transcripts to promote greater metabolic flux to the phenolic acid-branched pathway, via its interaction with SmAREB1 , a transcription factor. In this way, SmSnRK2.6 contributes to the positive regulation of phenolic acids in S. miltiorrhiza hairy roots.

  11. The Protein Kinase SmSnRK2.6 Positively Regulates Phenolic Acid Biosynthesis in Salvia miltiorrhiza by Interacting with SmAREB1

    Directory of Open Access Journals (Sweden)

    Yanyan Jia

    2017-08-01

    Full Text Available Subclass III members of the sucrose non-fermenting-1-related protein kinase 2 (SnRK2 play essential roles in both the abscisic acid signaling and abiotic stress responses of plants by phosphorylating the downstream ABA-responsive element (ABRE-binding proteins (AREB/ABFs. This comprehensive study investigated the function of new candidate genes, namely SmSnRK2.3, SmSnRK2.6, and SmAREB1, with a view to breeding novel varieties of Salvia miltiorrhiza with improved stress tolerance stresses and more content of bioactive ingredients. Exogenous ABA strongly induced the expression of these genes. PlantCARE predicted several hormones and stress response cis-elements in their promoters. SmSnRK2.6 and SmAREB1 showed the highest expression levels in the leaves of S. miltiorrhiza seedlings, while SmSnRK2.3 exhibited a steady expression in their roots, stems, and leaves. A subcellular localization assay revealed that both SmSnRK2.3 and SmSnRK2.6 were located in the cell membrane, cytoplasm, and nucleus, whereas SmAREB1 was exclusive to the nucleus. Overexpressing SmSnRK2.3 did not significantly promote the accumulation of rosmarinic acid (RA and salvianolic acid B (Sal B in the transgenic S. miltiorrhiza hairy roots. However, overexpressing SmSnRK2.6 and SmAREB1 increased the contents of RA and Sal B, and regulated the expression levels of structural genes participating in the phenolic acid-branched and side-branched pathways, including SmPAL1, SmC4H, Sm4CL1, SmTAT, SmHPPR, SmRAS, SmCHS, SmCCR, SmCOMT, and SmHPPD. Furthermore, SmSnRK2.3 and SmSnRK2.6 interacted physically with SmAREB1. In summary, our results indicate that SmSnRK2.6 is involved in stress responses and can regulate structural gene transcripts to promote greater metabolic flux to the phenolic acid-branched pathway, via its interaction with SmAREB1, a transcription factor. In this way, SmSnRK2.6 contributes to the positive regulation of phenolic acids in S. miltiorrhiza hairy roots.

  12. Detection of antifungal properties in Lactobacillus paracasei subsp. paracasei SM20, SM29, and SM63 and molecular typing of the strains.

    Science.gov (United States)

    Schwenninger, Susanne Miescher; von Ah, Ueli; Niederer, Brigitte; Teuber, Michael; Meile, Leo

    2005-01-01

    Lactobacilli isolated from different food and feed samples such as raw milk, cheese, yoghurt, olives, sour dough, as well as corn and grass silage, were screened for their antifungal activities. Out of 1,424 isolates tested, 82 were shown to be inhibitory to different yeasts (Candida spp. and Zygosaccharomyces bailii) and a Penicillium sp., which were previously isolated from spoiled yoghurt and fruits. Carbohydrate fermentation patterns suggested that a substantial portion, 25%, belonged to the Lactobacillus casei group, including L. casei, L. paracasei, and L. rhamnosus. The isolates SM20 (DSM14514), SM29 (DSM14515), and SM63 (DSM14516) were classified by PCR using species-specific primers to target the corresponding type strains (L. casei, L. paracasei, and L. rhamnosus) as controls. Further molecular typing methods such as randomly amplified polymorphic DNA, pulsed-field gel electrophoresis, and sequencing analysis of the 16S rRNA gene allowed classifying strains SM20, SM29, and SM63 as L. paracasei subsp. paracasei in accordance with the new reclassification of the L. casei group proposed by Collins et al.

  13. Ultrathin TaOx film based photovoltaic device

    International Nuclear Information System (INIS)

    Tyagi, Pawan

    2011-01-01

    Application of the economical metal oxide thin-film photovoltaic devices is hindered by the poor energy efficiency. This paper investigates the photovoltaic effect with an ultrathin tantalum oxide (TaOx) tunnel barrier, formed by the plasma oxidation of a pre-deposited tantalum (Ta) film. These ∼ 3 nm TaOx tunnel barriers showed approximately 160 mV open circuit voltage and 3-5% energy efficiency, for varying light intensity. The ultrathin TaOx (∼ 3 nm) could absorb approximately 12% of the incident light radiation in 400-1000 nm wavelength range; this strong light absorbing capability was found to be associated with the dramatically large extinction coefficient. Spectroscopic ellipsometry revealed that the extinction coefficient of 3 nm TaOx was ∼ 0.2, two orders higher than that of tantalum penta oxide (Ta 2 O 5 ). Interestingly, refractive index of this 3 nm thick TaOx was comparable with that of stochiometeric Ta 2 O 5 . However, heating and prolonged high-intensity light exposure deteriorated the photovoltaic effect in TaOx junctions. This study provides the basis to explore the photovoltaic effect in a highly economical and easily processable ultrathin metal oxide tunnel barrier or analogous systems.

  14. Preparation of Ta Te2 thin films by laser ablation

    International Nuclear Information System (INIS)

    Zidan, M.D.; Alkhwam, M.; Alkhasm, M.

    2006-03-01

    The laser ablation system consisting of a vacuum chamber and Nd-YAG laser has been built for deposition TaTe 2 on three different substrates (Silicon, glass, and Aluminium). The surface topography of the prepared thin films has been studied by atomic force microscopy (AFM). TaTe 2 powder was characterized by using x-ray diffraction. The crystallinity of the thin films was examined by x-ray diffraction (XRD). The results show no peaks corresponding TaTe 2 , but there are some indications to the Ta 3 N 5 . (author)

  15. Thermodynamic description of the Ta-W-Zr system

    International Nuclear Information System (INIS)

    Guo, Cuiping; Li, Changrong; Du, Zhenmin; Shang, Shunli

    2014-01-01

    The Ta-W, W-Zr and Ta-W-Zr systems are critically reviewed and modeled using the CALPHAD technique. The enthalpy of formation of the stoichiometric compound W 2 Zr in the W-Zr system is predicted from first-principles calculations. The solution phases (liquid, bcc and hcp) are modeled by the substitutional solution model. The compound W 2 Zr is treated with the formula (Ta,W) 2 Zr in the Ta-W-Zr system because of a significant solid solubility of Ta in W 2 Zr. All experimental data, including the Gibbs energy of formation, enthalpy of formation, activity of Ta and W of bcc phase at 1 200 K, Ta-W and W-Zr phase diagrams, and three isothermal sections of the Ta-W-Zr system at 1 073, 1 098, and 1 873 K, are reproduced in the present work. A set of self-consistent thermodynamic parameters of the Ta-W-Zr system is obtained.

  16. Ferrimagnetic properties of Co/(Gd-Co) multilayers

    International Nuclear Information System (INIS)

    Svalov, A.V.; Fernandez, A.; Vas'kovskiy, V.O.; Tejedor, M.; Barandiaran, J.M.; Orue, I.; Kurlyandskaya, G.V.

    2006-01-01

    Co/(Gd-Co) multilayers have been prepared by rf-sputtering and investigated by means of Transverse Magnetooptic Kerr Effect (TMOKE), SQUID and VSM magnetometry. The composition of amorphous Gd 0.36 Co 0.64 layers was chosen so that their saturation magnetization was dominated by Gd moments in all the temperature range. Co and Gd-Co layers formed a macroscopic ferrimagnetically coupled system displaying a compensation temperature. Complete magnetic moment compensation was found at such point. An inversion of TMOKE hysteresis loops and a divergent behaviour of coercivity were also observed. By changing the layers thickness it has been possible to control the magnetic characteristics of the Co/(Gd-Co) structures, in particular the compensation takes place at different temperatures

  17. Assessment of microseeds biodegradability of Sm and Sm:Ba splenic implants in rabbits

    International Nuclear Information System (INIS)

    Siqueira, Savio Lana; Barroso, Thiago Vinicius Villar; Campos, Tarcisio P.R.

    2009-01-01

    The radioactive interstitial implants have applications in controlling neoplasm in several regions of the human body. Currently the permanent brachytherapy seeds implanted in the spleen and other organs are made of I-125 seeds. After the total emission of radiation, the metal encapsulated seed remains inert in the implanted area. Seeds of bioactive ceramics have been prepared with Sm-152 incorporation to be activated in Sm-153. This study aimed to develop surgical technique for implanting biodegradable micro-seeds in the spleen of the rabbit. Three micro-seeds were introduced by hypodermic needle in the spleen in eight rabbits by median laparotomy. Subsequently, there were clinical and functional reactions of the animal to the implanted foreign body. The other objective was to perform the animal monitoring by radiography, produced in time sequence, and pathological studies of a fragment of the spleens of rabbits. The results show the effectiveness of surgery, the identification of the implanted material by radiography in vivo, and the biocompatibility of micro-seeds most of Sm and Sm:Ba. These seeds of reduced volume, 0.3x 1.6 mm, could be monitored for radiological studies in 2 periods: early and later implant. On the later studies, radiography was taken at 60d post-implant. Biopsies were taken and radiographs of the samples were also performed for evidencing the degradation state of the seeds. The results of the two groups of four rabbits are presented. They show partial degradation of the seed verified by radiographic contrast which is related to the atomic number of the elements and mass density in the seed. The biopsy showed that the ceramic is clearly absorbed by the spleen tissue and form tissue-implant interface. The histological slides showed an inflammatory reaction with presence of fibrosis of the giant cell foreign body. In conclusion, the radiograph shows a suitable noninvasive technique for monitoring the degradation of micro-seed ceramics in vivo

  18. Assessment of microseeds biodegradability of Sm and Sm:Ba splenic implants in rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Savio Lana; Barroso, Thiago Vinicius Villar [Faculdade de Ciencias Medicas de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Anatomia; Campos, Tarcisio P.R., E-mail: campos@nuclear.ufmg.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Ciencias e Tecnicas Nucleares

    2009-07-01

    The radioactive interstitial implants have applications in controlling neoplasm in several regions of the human body. Currently the permanent brachytherapy seeds implanted in the spleen and other organs are made of I-125 seeds. After the total emission of radiation, the metal encapsulated seed remains inert in the implanted area. Seeds of bioactive ceramics have been prepared with Sm-152 incorporation to be activated in Sm-153. This study aimed to develop surgical technique for implanting biodegradable micro-seeds in the spleen of the rabbit. Three micro-seeds were introduced by hypodermic needle in the spleen in eight rabbits by median laparotomy. Subsequently, there were clinical and functional reactions of the animal to the implanted foreign body. The other objective was to perform the animal monitoring by radiography, produced in time sequence, and pathological studies of a fragment of the spleens of rabbits. The results show the effectiveness of surgery, the identification of the implanted material by radiography in vivo, and the biocompatibility of micro-seeds most of Sm and Sm:Ba. These seeds of reduced volume, 0.3x 1.6 mm, could be monitored for radiological studies in 2 periods: early and later implant. On the later studies, radiography was taken at 60d post-implant. Biopsies were taken and radiographs of the samples were also performed for evidencing the degradation state of the seeds. The results of the two groups of four rabbits are presented. They show partial degradation of the seed verified by radiographic contrast which is related to the atomic number of the elements and mass density in the seed. The biopsy showed that the ceramic is clearly absorbed by the spleen tissue and form tissue-implant interface. The histological slides showed an inflammatory reaction with presence of fibrosis of the giant cell foreign body. In conclusion, the radiograph shows a suitable noninvasive technique for monitoring the degradation of micro-seed ceramics in vivo

  19. The production and use of a 148Gd charged particle target in a spectroscopic study of 147Gd

    International Nuclear Information System (INIS)

    Massey, T.N.

    1988-01-01

    This thesis discusses the nuclear structure of 147 Gd elucidated by the neutron pickup reactions (p,d), (d,t) and ( 3 He,α) on the unstable 148 Gd target. The neutron pickup reaction on 148 Gd probes the two-particle-one-hole states by the pickup of neutrons in the shell model orbitals below the N = 82 gap and one-particle states by pickup of neutrons in shell model orbitals above the N = 82 gap. Our experiments will provide information on the location of neutron single-particle energies which can be used for shell-model calculations in the 146 Gd region. The 2-particle-1-hole (2p-1h) states which are probed directly by the neutron transfer reaction in the experiments with the 148 Gd target, will bear indirectly on the energies of one-hole states in 145 Gd. They will also provide information on the strongest single-particle states in 147 Gd because all the single-particle states in the 148 Gd target are partially occupied because of the mixing by the pairing interaction. 107 refs., 23 figs., 20 tabs

  20. The magnetic hyperfine field in the 181Ta site in the Co2HfAl and Co2HfGa Heusler alloys

    International Nuclear Information System (INIS)

    Silva, R. da.

    1979-01-01

    The hyperfine magnetic fields at 181 Ta nuclei in Heusler alloys Co 2 HfZ (Z=Al, Ga) have been measured using the time differential perturbed gamma-gamma angular correlation (TDPAC) method. The hyperfine fields obtained from these measurements at the liquid nitrogen temperature are -189 and +- 150 kOersted for Co 2 HfAl and Co 2 HfGa, respectively. The concept that the hyperfine field at the Y site is similar to the solute fields in Fe, Co, Ni and Gd matrices is corroborated. We have verified that ratios H sub(hf) sub(Ta)/T sub(c) and H sub(hf) sub(Ta)μ sub(Co) in Co 2 HfZ compounds (Z=Al, Ga, Sn) do not depend on the nature of Z element. However a dependence in the value of observed field with the s-p element in Z site was noticed. We feel that the samples are not completely ordered cubic as observed by the quadrupole interaction measurements. The results are interpreted in terms of the Campbell-Blandin formalism, and it is shown that the spin polarization of conduction electrons at Hf and Ta have opposite signs. (Author) [pt

  1. Peculiar features of thermal emission of GdB4 and GdB6 single crystals

    International Nuclear Information System (INIS)

    Ostrovskij, E.K.; Taran, A.A.; Kovalev, A.V.; Tkachenko, V.F.; Dudnik, E.M.; Matvienko, A.A.

    1990-01-01

    Thermoemission parameters of single crystals (410) GdB 4 and (110) GdB 6 are studied. Work function is calculated by total current. It is stated that work function of GdB 6 within temperature range of 1500-1880 K after 80 h of annealing varies from 2.95 to 3.10 eV practically with the same temperature coefficient as GdB 4 , i.e. 4.1x10 -4 eV/K. It is shown that single crystal gadolinium hexaboride during the high-temperature annealing in the surface region (∼70 mm) is transformed into gadolinium tetraboride. Influence of free air has been first studied on the GdB 4 emissivity which is determined to increase to p=1.3x10 -2 Pa within the range of T=1640-1840 K

  2. Test of E1-radiative strength function and level density models by 155 Gd (n,2γ) 156 Gd reaction

    International Nuclear Information System (INIS)

    Voinov, A.V.

    1996-01-01

    The information about the level density of 156 Gd nucleus and strength functions of γ transitions extracted from two γ-cascade spectra of the 155 Gd (n,2γ) 156 Gd reaction is analyzed. The method of statistical simulation of γ-cascade intensity is applied for calculation of the main parameters of experimental spectra. The method is used to extract the information on the E1-radiative strength function of γ transitions and level density in the 156 Gd nucleus. It is shown that at an excitation energy above 3 MeV the level density of 156 Gd nucleus must decrease in comparison with that calculated within the Fermi gas model. Its is concluded that possible explanation of the observed effect is connected with the influence of pairing correlations on the level density in nuclei

  3. Synthesis, characterization and thermal behavior: Gd(NO3)3.6H2O to Gd2O3

    International Nuclear Information System (INIS)

    Ghonge, Darshana K.; Sheelvantra, Smita S.; Kalekar, Bhupesh B.; Raje, Naina

    2015-01-01

    Gadolinium oxide finds its application in nuclear as well as medical industry. It has been prepared from the thermal decomposition of gadolinium nitrate hexahydrate. Surface area of the synthesized compound was measured as 19 m 2 /g. EDS data shows only the presence of gadolinium and oxygen in the synthesized compound with the Gd to O ratio as calculated for Gd 2 O 3 , suggests the formation of pure Gd 2 O 3 . XRD analysis confirms the formation of pure cubic phase Gd 2 O 3 . In the absence of any report on the thermal behavior of GdNH, present studies have been carried out to understand the decomposition mechanism using simultaneous TG - DTA - EGA measurements

  4. New perspective for GdNCT. Gd-DTPA reaches the nucleus of glioblastoma cells in culture and in vivo

    International Nuclear Information System (INIS)

    Stasio, G. de; Gilbert, B.; Frazer, B.H.

    2000-01-01

    We investigated the prospects of gadolinium as a neutron capture therapy agent by combining three independent techniques to study the uptake of Gd-DTPA in vitro, in cultured glioblastoma cells, and in vivo, in the glioblastoma tissue sections after injection of Gd-DTPA and tumor extraction. We show that gadolinium not only penetrates the plasma membrane of glioblastoma cells grown in culture, but we also observe a statistically significant higher concentration of Gd in the nucleus relative to the cytoplasm. For the in vivo experiments, Gd-DTPA was administered to 6 glioblastoma patients before neurosurgery. The extracted bioptic tissue was then analyzed with spectromictroscopy, showing Gd localized in the nuclei of glioblastoma cells in 5 patients out of the 6 analyzed. (author)

  5. Search for superdeformation in 144Gd

    International Nuclear Information System (INIS)

    Vivien, J.P.; Nourreddine, A.; Beck, F.A.; Byrski, T.; Gehringer, C.; Haas, B.; Merdinger, J.C.; Dudek, J.; Nazarewicz, W.

    1986-01-01

    Quasi-continuum γ-decay studies of 144 Gd have been performed using the 120 Sn( 28 Si,4n)reaction at 125, 135, 145 and 155 MeV bombarding energies. Angular distribution and multiplicity measurements have been done at the above energies. At 145 MeV bombarding energy a lifetime measurement has also been performed. Although a collective behaviour has been observed, the present data do not give evidence for population of superdeformed rotational bands. Theoretical interpretation using the cranking model with the Woods-Saxon field is given. The effects of temperature and pairing on the superdeformed configuration are discussed; superdeformation effects are predicted to disappear below I ∼ 60-70 ℎ when temperature exceeds ∼ 500 KeV

  6. Non-ionic contributions to the electric-field gradient at {sup 111}Cd/{sup 181}Ta impurities in bixbyites

    Energy Technology Data Exchange (ETDEWEB)

    Renteria, Mario [Universidad Nacional de La Plata, Departamento de Fisica, Facultad de Ciencias Exactas (Argentina); Freitag, Kristian [Universitaet Bonn, Institut fuer Strahlen- und Kernphysik (ISKP) (Germany); Errico, Leonardo A. [Universidad Nacional de La Plata, Departamento de Fisica, Facultad de Ciencias Exactas (Argentina)

    1999-09-15

    The electric-field-gradient (EFG) tensor at both cation sites of the bixbyite structure in {sup 181}Hf-implanted Lu- and Sm-sesquioxides was determined by the PAC technique. The cumulated EFG data at Ta-impurity sites in binary oxides enable us to discuss the 'universal' character of the empirical correlation between local and ionic contributions to the EFG in these systems. An EFG factorization in terms of the electronic characteristics of the probe and the geometry of the cation coordination is proposed, which explains the experimental EFG results at Ta/Cd impurity sites in bixbyites and agrees with a simplified decomposition of the EFG valence contribution coming from ab-initio calculations.

  7. New orthorhombic derivative of CaCu{sub 5}-type structure: RNi{sub 4}Si compounds (R=Y, La, Ce, Sm, Gd–Ho), crystal structure and some magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Morozkin, A.V., E-mail: morozkin@general.chem.msu.ru [Department of Chemistry, Moscow State University, Leninskie Gory, House 1, Building 3, GSP-2, Moscow 119992 (Russian Federation); Knotko, A.V. [Department of Chemistry, Moscow State University, Leninskie Gory, House 1, Building 3, GSP-2, Moscow 119992 (Russian Federation); Yapaskurt, V.O. [Department of Petrology, Geological Faculty, Moscow State University, Leninskie Gory, Moscow 119992 (Russian Federation); Yuan, Fang; Mozharivskyj, Y. [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1 (Canada); Nirmala, R. [Indian Institute of Technology Madras, Chennai 600036 (India)

    2013-12-15

    The crystal structure of new YNi{sub 4}Si-type RNi{sub 4}Si (R=Y, La, Ce, Sm, Gd–Ho) compounds has been established using powder X-ray diffraction. The YNi{sub 4}Si structure is a new structure type, which is orthorhombic derivative of CaCu{sub 5}-type structure (space group Cmmm N 65, oC12). GdNi{sub 4}Si and DyNi{sub 4}Si compounds order ferromagnetically at 25 and 19 K, respectively whereas YNi{sub 4}Si shows antiferromagnetic nature. At 15 K, DyNi{sub 4}Si shows second antiferromagnetic-like transition. The magnetic moment of GdNi{sub 4}Si at 5 K in 50 kOe field is ∼7.2 μ{sub B}/f.u. suggesting a completely ordered ferromagnetic state. The magnetocaloric effect of GdNi{sub 4}Si is calculated in terms of isothermal magnetic entropy change and it reaches the maximum value of −12.8 J/kg K for a field change of 50 kOe near T{sub C} ∼25 K. - Graphical abstract: The RNi{sub 4}Si (R=Y, La, Ce, Sm, Gd–Ho) compounds crystallize in new YNi{sub 4}Si-type structure which is orthorhombic derivative of the basic CaCu{sub 5}-type structure. GdNi{sub 4}Si and DyNi{sub 4}Si compounds show the ferromagnetic-like ordering, whereas.YNi{sub 4}Si has the antiferromagnetic nature. The GdNi{sub 4}Si demonstrates the big magnetocaloric effect near temperature of ferromagnetic ordering. The relationship between initial CaCu{sub 5}-type DyNi{sub 5} and YNi{sub 4}Si-type DyNi{sub 4}Si lattices.

  8. Electroexcitation of giant resonances in 181Ta

    International Nuclear Information System (INIS)

    Hicks, R.S.; Auer, I.P.; Bergstrom, J.C.; Caplan, H.S.

    1977-01-01

    The giant resonance region of 181 Ta has been investigated by means of inelastic electron scattering with primary electron energies of 79.1 to 118.3 MeV. A peak-fitting procedure was employed to separate the measured spectrum into nine different resonance components. Multipolarity and strength assignments were deduced using DWBA analysis with the Goldhaber-Teller and Steinwedel-Jensen models. In addition to the well-known giant dipole structure, other resonances were identified at 23.2+-0.3 MeV (E2), 9.5+-0.2 and 11.5+-0.2 MeV (E2 or E0), 19.5+-0.8 MeV (E3), 3.70+-0.14 MeV (E3 or E4), and 5.40+-0.15 MeV (E4 or E5). The model dependence of the analysis is discussed. (Auth.)

  9. The Mo/Ta (100) interface

    International Nuclear Information System (INIS)

    Quintanar, C.; Velasco, V.R.; Garcia-Moliner, F.

    1990-12-01

    We have calculated the interface local density of states (ILDOS) formed by the transition metals Mo/Ta using a tight-binding Slater-Koster description and the Green Function matching method together with quickly converging algorithms to compute the transfer matrices. We obtain the surface LDOS as a byproduct. Our result is a useful tool to analyze experimental results and to check models as a function of the value of the tight-binding parameters either of the bulk or at the interface itself. We consider the (100) direction. We compare the interface to the bulk and to the surface and comment on some recently found experimental results for this interface. (author). 17 refs, 2 figs

  10. LRAD surface monitoring results at TA-21

    International Nuclear Information System (INIS)

    Bounds, J.A.

    1995-01-01

    In August/September 1994, NIS-6 personnel used LRAD soil surface monitor technology to characterize the extent of alpha contamination on the surface of a parking lot adjacent to TA-21, LANL, known as Material Disposal Area B. This report documents that monitoring. Based on this survey, there is no reason for concern about significant contamination in the parking area as a whole, although unexpected small hot spots could exist between the grid points where monitoring was performed. However, the grouping of high readings on the east side of the parking area does point to possible contamination at the level of 100 dpm/100 cm 2 or less (above background). Further monitoring or remediation of this area seems appropriate. In addition, because this was an alpha survey, one cannot rule out contamination under the asphalt or possibly between layers if it was paved more than once

  11. Determination of the {sup 151}Sm half-life

    Energy Technology Data Exchange (ETDEWEB)

    Be, Marie-Martine; Cassette, Philippe [CEA, LIST, Gif sur Yvette (France). LNE-Laboratoire National Henri Becquerel; Isnard, Helene [CEA-LANIE, Gif sur Yvette (France); and others

    2015-07-01

    New measurements have been undertaken to determine the half-life of {sup 151}Sm. A pure {sup 151}Sm solution was obtained after chemical separation from a samarium solution resulting from the dissolution of an irradiated samarium sample. The concentration of {sup 151}Sm in the solution was measured by mass spectrometry, combined with the isotope dilution technique. The activity of the solution was measured by liquid scintillation counting by six European laboratories as part of an international comparison. These combined results lead to a half-life of T{sub 1/2} = 94.6(6)a.

  12. Magnetism and Hyperfine Parameters in Iron Rich Gd_2Fe_{17-x}Si_x Intermetallics

    Science.gov (United States)

    Nouri, K.; Bartoli, T.; Chrobak, A.; Moscovici, J.; Bessais, L.

    2018-04-01

    Gd_2Fe_{17-x}Si_x (x = 0.25 , 0.5 and 1) samples were synthesized by arc melting and annealed at 1073 K for 1 week. X-ray diffraction analysis by the Rietveld method has shown that these materials crystallize in the rhombohedral Th_2Zn_{17} -type structure (space group R\\bar{3}m ). The Curie temperature increases with Si content x, whereas the unit-cell parameters decrease slightly. The temperature dependence of magnetization data revealed that Gd_2Fe_{17-x}Si_x exhibits a second-order ferromagnetic to paramagnetic phase transition in the vicinity of the Curie temperature. Exchange coupling parameters of R-R, M-M and R-M (R—rare earth, M—transition metal) have been determined from M(T) magnetization curves based on the mean field theory calculation. The magnetic entropy change Δ S_M and the relative cooling power were estimated from isothermal magnetization curves for all samples. In the proximity of {T}_C and in an applied field of 1.56 T, Δ S_M reached a maximum values of 1.38, 1.67 and 3.07 J/kg K for x = 0.25, 0.5 and 1, respectively. We have calculated the magnetic moment per Fe atom from magnetization measurements at 293 K up to 17 kOe, and it decreases with Si content. These results are verified by the Mössbauer spectrometry measurements obtained at the same temperature. The Mössbauer spectra analysis is based on the correlation between the Wigner-Seitz volume and the isomer-shift evolution of each specific site 6c, 9d, 18f, and 18h of the R\\bar{3} m structure. For all Si concentrations, the magnitude of the hyperfine fields are {H_HF}{6c} > {H_HF}{9d} > {H_HF}{18f} > {H_HF}{18h} . The mean hyperfine field decreases with the Si content.

  13. GdF Suez, the real energy champion

    International Nuclear Information System (INIS)

    Dupin, L.

    2010-01-01

    During summer 2010, France discovered that she owned a second energy giant, GdF Suez, ranked number two as a power producer just behind EdF, but world number one in the energy domain thanks to the taking over of International Power (UK) in 2010. Until now, GdF Suez and EdF were confronting with each other in a fair game, keeping their respective seizure on their historical monopolies, gas for GdF Suez and electricity for EdF. From now onward the two giants have started an open fight on all markets, with the exception of nuclear energy for which the French government continues to favour EdF. This paper recalls the main steps of the last 15 years of GdF Suez progress, from the Suez investment bank in 1995 to the merger with GdF in 2008 and the acquisition of International Power in 2010. Then it makes a comparative portrait of both GdF Suez and EdF energy groups with their respective advantages and, finally, it ends with an interview of G. Mestrallet, president of GdF Suez who explains the strategy of his group. (J.S.)

  14. Fabrication and photoluminescence properties of color-tunable light emitting lanthanide doped GdVO{sub 4} hierarchitectures

    Energy Technology Data Exchange (ETDEWEB)

    Amurisana, Bao, E-mail: amurisana@163.com [Institute of Chemical Biology, Hohhot Vocational College, Hohhot 010051 (China); Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials, Inner Mongolia Normal University, Hohhot 010022 (China); Bao, Lihong [Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials, Inner Mongolia Normal University, Hohhot 010022 (China); Bao, Liang [Institute of Chemical Biology, Hohhot Vocational College, Hohhot 010051 (China); Tegus, O., E-mail: tegusph@imnu.edu.cn [Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials, Inner Mongolia Normal University, Hohhot 010022 (China)

    2017-04-15

    The flower-like GdVO{sub 4}:Ln{sup 3+}( Ln{sup 3+}=Eu{sup 3+}, Dy{sup 3+}, Sm{sup 3+}, Tm{sup 3+}) hierarchitectures have been successfully synthesized on a glass slide substrate through a one-pot hydrothermal route assisted by disodium ethylenediaminetetraacetic acid (Na{sub 2}H{sub 2}L, where L{sup 4-}=(CH{sub 2}COO){sub 2}N(CH{sub 2}){sub 2}N(CH{sub 2}COO){sub 2}{sup 4-}). A high density and ordered flower-like GdVO{sub 4}:Ln{sup 3+} hierarchitectures grew epitaxially on glass substrate. The as-prepared flower-like architectures with the size about 6 μm are constructed by the numerous radially oriented single-crystalline nanorods with the width from 20 nm to 200 nm and the length from 500 nm to 3 μm. The morphologies, the thickness, and the density of as-grown flower clusters can be readily tuned by tailoring the growth time and Na{sub 2}H{sub 2}L/Gd{sup 3+} molar ratio. The possible formation mechanism of flower-like GdVO{sub 4}:Ln{sup 3+} hierarchitectures is discussed on the basis of the results from the controlled experiments under hydrothermal conditions. Because of an energy transfer from vanadate groups to dopants, the flower-like GdVO{sub 4}:Ln{sup 3+}( Ln{sup 3+}=Eu{sup 3+}, Dy{sup 3+}, Sm{sup 3+} and Tm{sup 3+}) superstructures showed strong characteristic dominant emissions of the Eu{sup 3+}, Dy{sup 3+}, Sm{sup 3+} and Tm{sup 3+} ions at 617 nm ({sup 5}D{sub 0}→{sup 7}F{sub 2}, strong red), 575 nm ({sup 4}F{sub 9/2}→{sup 6}H{sub 13/2}, yellow), 604 nm ({sup 4}G{sub 5/2}→{sup 6}H{sub 7/2}, orange-red) and 476 nm ({sup 1}G{sub 4}–{sup 3}H{sub 6}, blue) under ultraviolet excitation, respectively.Further, the emission color of the product can also be tuned by selecting the dopant Ln{sup 3+} with characteristic emissions and varying the concentration ratio of co-doping activators. This approach could be extended to the fabrication of hierarchical structures for other oxide micro/nanomaterials, and may provide a general way to achieve multicolor

  15. Luminescence properties of the Sm-doped borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Kindrat, I.I. [University of Zielona Góra, Institute of Physics, Division of Spectroscopy of Functional Materials, 4a Szafrana Street, 65-516 Zielona Góra (Poland); Padlyak, B.V., E-mail: B.Padlyak@if.uz.zgora.pl [University of Zielona Góra, Institute of Physics, Division of Spectroscopy of Functional Materials, 4a Szafrana Street, 65-516 Zielona Góra (Poland); Vlokh Institute of Physical Optics, 23 Dragomanov Street, 79-005 Lviv (Ukraine); Drzewiecki, A. [University of Zielona Góra, Institute of Physics, Division of Spectroscopy of Functional Materials, 4a Szafrana Street, 65-516 Zielona Góra (Poland)

    2015-10-15

    The optical absorption and photoluminescence (emission and excitation) spectra as well as decay kinetics of a series of the Sm-doped glasses with Li{sub 2}B{sub 4}O{sub 7}, LiKB{sub 4}O{sub 7}, CaB{sub 4}O{sub 7}, and LiCaBO{sub 3} compositions were investigated and analysed. The Li{sub 2}B{sub 4}O{sub 7}:Sm, LiKB{sub 4}O{sub 7}:Sm, CaB{sub 4}O{sub 7}:Sm, and LiCaBO{sub 3}:Sm glasses of high optical quality have been obtained from the corresponding polycrystalline compounds in the air atmosphere, using a standard glass technology. On the basis of electron paramagnetic resonance (EPR) and optical spectra analysis it was shown that the samarium impurity is incorporated into the glass network as Sm{sup 3+} (4f{sup 5}, {sup 6}H{sub 5/2}) ions, exclusively. All observed 4f – 4f transitions of the Sm{sup 3+} centres in the optical absorption and luminescence spectra of the investigated glasses are identified. Most intense emission band of the Sm{sup 3+} ions peaked about 598 nm ({sup 4}G{sub 5/2} → {sup 6}H{sub 7/2} transition) is characterised by a single exponential decay with typical lifetime values, which depend on the basic glass composition as well as concentration and local structure of the Sm{sup 3+} luminescence centres. The quantum efficiency has been evaluated for observed transitions of the Sm{sup 3+} centres using obtained experimental lifetimes and radiative lifetimes calculated by Judd–Ofelt theory. The calculated high quantum efficiencies and measured quantum yields of luminescence show that the investigated borate glasses are perspective luminescence materials. Energy transfer from the Ce{sup 3+} non-controlled impurity and intrinsic luminescence centres to the Sm{sup 3+} centres has been observed. Peculiarities of the Sm{sup 3+} local structure in the network of investigated glasses have been discussed based on the obtained spectroscopic results and structural data. - Highlights: • The Sm-doped Li{sub 2}B{sub 4}O{sub 7}, LiKB{sub 4}O{sub 7}, Ca

  16. The TaSST: Tactile Sleeve for Social Touch

    NARCIS (Netherlands)

    Huisman, G.; Darriba Frederiks, A.; van Dijk, B.; Heylen, D.; Kröse, B.

    2013-01-01

    In this paper we outline the design process of the TaSST (Tactile Sleeve for Social Touch), a touch-sensitive vibrotactile arm sleeve. The TaSST was designed to enable two people to communicate different types of touch over a distance. The touch-sensitive surface of the sleeve consists of a grid of

  17. The TaSST: Tactile sleeve for social touch

    NARCIS (Netherlands)

    Huisman, Gijs; Darriba Frederiks, Aduén; van Dijk, Elisabeth M.A.G.; Heylen, Dirk K.J.; Krose, Ben

    In this paper we outline the design process of the TaSST (Tactile Sleeve for Social Touch), a touch-sensitive vibrotactile arm sleeve. The TaSST was designed to enable two people to communicate different types of touch over a distance. The touch-sensitive surface of the sleeve consists of a grid of

  18. The TaSST - Tactile Sleeve for Social Touch

    NARCIS (Netherlands)

    Huisman, Gijs; Darriba Frederiks, Aduén; Van Dijk, Betsy; Heylen, Dirk

    2013-01-01

    In this paper we outline the design process of TaSST (Tactile Sleeve for Social Touch), a touch-sensitive vibrotactile arm sleeve. The TaSST was designed to enable two people to communicate different types of touches over a distance. The touch-sensitive surface of the sleeve consists of a grid of

  19. 76 FR 50739 - Hung Ta Fan: Debarment Order

    Science.gov (United States)

    2011-08-16

    ...] Hung Ta Fan: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The... (the FD&C Act) debarring Hung Ta Fan for a period of 5 years from importing articles of food or.... Fan was convicted of a felony under Federal law for conduct relating to the importation into the...

  20. Influence of the size of Gd211 starting powder on the critical current density of Gd-Ba-Cu-O bulk superconductor

    International Nuclear Information System (INIS)

    Nariki, S.; Seo, S.J.; Sakai, N.; Murakami, M.

    2000-01-01

    The relationship between the particle size of Gd211 powder in the precursor and the particle size of Gd211 inclusions in Gd-Ba-Cu-O bulk has been investigated. Gd211 starting powders with various diameters were prepared by the calcination of Gd 2 O 3 , BaO 2 and CuO powders at different temperatures between 800 and 1000 deg. C. The particle size of Gd211 in the melt-grown bulk was proportional to the particle size of the initial Gd211 powder. In conclusion, the employment of fine Gd211 powder led to a size reduction of 211 particles in the bulk, while largely enhancing the J c values in low magnetic fields. A large Gd-Ba-Cu-O/Ag bulk sample, 32 mm in diameter, could also be fabricated by the hot-seeding method. The maximum trapped field value revealed 1.5 T at 77 K. (author)

  1. HDDR in Sm-Co alloys - a new method for magnetic hardening of Sm-Co permanent magnets

    Energy Technology Data Exchange (ETDEWEB)

    Kubis, M.; Handstein, A.; Gebel, B.; Mueller, K.-H.; Schultz, L. [Institut fuer Festkoerper- und Werkstofforschung Dresden e.V. (Germany). Inst. fuer Metallische Werkstoffe; Gutfleisch, O. [Institut fuer Festkoerper- und Werkstofforschung Dresden e.V. (Germany). Inst. fuer Metallische Werkstoffe]|[Birmingham Univ. (United Kingdom). School of Metallurgy and Materials

    1998-07-01

    Investigations on the hydrogen absorption behavior of different Sm-Co alloys with 1:5 and 2:17 structure by differential scanning calorimetry (DSC) at enhanced hydrogen pressures between 1 MPa and 7 MPa indicated different hydrogen absorption events. X-ray diffraction (XRD) studies and microstructural investigations showed clearly the disproportionation of the Sm-Co phases into Sm hydride and Co or Co-rich phases for hydrogen pressures above 0.5 MPa. The favourable effect of high hydrogen pressures can be explained in terms of a decrease of the free enthalpy of the samarium hydride for increasing hydrogen pressures. Additionally, Sm-Co alloys of both types were reactively milled under hydrogen at enhanced temperatures. The reactively milled powders showed again the products of the disproportionation reaction. A recombination of Sm-Co phases by removing the hydrogen in a second heat treatment was successful for both methods. Investigations of the magnetic properties showed coercivities {mu}{sub OJ}H{sub C} of up to 2.1 T for high pressure HDDR powders of SmCo{sub 5} material, demonstrating clearly the positive effect of the hydrogen treatment on the coercivity. The reactively milled powders showed for recombination temperatures {<=}700 C a remanence enhancement which could be attributed to the exchange coupling of the nanoscaled grains. A maximum coercivity {mu}{sub OJ}H{sub C} of 3.7 T was achieved for SmCo{sub 5} and a maximum energy product (BH){sub max} of 82 kJ/m{sup 3} was measured for an Sm-rich Sm{sub 2}Co{sub 17} sample. (orig.)

  2. HDDR in Sm-Co alloys - a new method for magnetic hardening of Sm-Co permanent magnets

    International Nuclear Information System (INIS)

    Kubis, M.; Handstein, A.; Gebel, B.; Mueller, K.-H.; Schultz, L.; Gutfleisch, O.; Birmingham Univ.

    1998-01-01

    Investigations on the hydrogen absorption behavior of different Sm-Co alloys with 1:5 and 2:17 structure by differential scanning calorimetry (DSC) at enhanced hydrogen pressures between 1 MPa and 7 MPa indicated different hydrogen absorption events. X-ray diffraction (XRD) studies and microstructural investigations showed clearly the disproportionation of the Sm-Co phases into Sm hydride and Co or Co-rich phases for hydrogen pressures above 0.5 MPa. The favourable effect of high hydrogen pressures can be explained in terms of a decrease of the free enthalpy of the samarium hydride for increasing hydrogen pressures. Additionally, Sm-Co alloys of both types were reactively milled under hydrogen at enhanced temperatures. The reactively milled powders showed again the products of the disproportionation reaction. A recombination of Sm-Co phases by removing the hydrogen in a second heat treatment was successful for both methods. Investigations of the magnetic properties showed coercivities μ OJ H C of up to 2.1 T for high pressure HDDR powders of SmCo 5 material, demonstrating clearly the positive effect of the hydrogen treatment on the coercivity. The reactively milled powders showed for recombination temperatures ≤700 C a remanence enhancement which could be attributed to the exchange coupling of the nanoscaled grains. A maximum coercivity μ OJ H C of 3.7 T was achieved for SmCo 5 and a maximum energy product (BH) max of 82 kJ/m 3 was measured for an Sm-rich Sm 2 Co 17 sample. (orig.)

  3. Phantom and animal studies of a new hepatobiliary agent for MR imaging: comparison of Gd-DTPA-DeA with Gd-EOB-DTPA.

    Science.gov (United States)

    Yoshikawa, Kohki; Inoue, Yusuke; Akahane, Masaaki; Shimada, Morio; Itoh, Sayaka; Seno, Atsushi; Hayashi, Sanshin

    2003-08-01

    To investigate the characteristics of Gd-DTPA-DeA as a hepatobiliary contrast agent for MR imaging in comparison with those of Gd-EOB-DTPA. We undertook phantom experiments to assess T1 relaxivity for Gd-DTPA-DeA, Gd-EOB-DTPA, and Gd-DTPA in human plasma. For Gd-DTPA-DeA and Gd-EOB-DTPA, we evaluated the contrast effect in rats using an SPGR sequence. The contrast ratios of liver and abdominal aorta were measured up to 21 minutes after intravenous administration of the agents. Visualization of the bile duct and renal pelvis was also assessed. In human plasma, T1 relaxivity was similar for Gd-DTPA-DeA and Gd-EOB-DTPA, and higher than those for Gd-DTPA. Whereas the contrast ratio of liver peaked about five minutes after the injection of Gd-EOB-DTPA and was followed by a subsequent decline, a continuous rise was shown for Gd-DTPA-DeA, resulting in a larger maximal contrast effect. Contrast ratios of the abdominal aorta were larger for Gd-DTPA-DeA. Biliary excretion was observed for both agents but occurred earlier with Gd-EOB-DTPA. While renal excretion was shown for all rats three minutes after the injection of Gd-EOB-DTPA, it was not observed for Gd-DTPA-DeA. Gd-DTPA-DeA may be used as a hepatobiliary contrast agent and shows different pharmacokinetics from Gd-EOB-DTPA. Copyright 2003 Wiley-Liss, Inc.

  4. Magnetoelastic behaviour of Gd sub 5 Ge sub 4

    CERN Document Server

    Magen, C; Algarabel, P A; Marquina, C; Ibarra, M R

    2003-01-01

    A complete investigation of the complex magnetic behaviour of Gd sub 5 Ge sub 4 by means of linear thermal expansion and magnetostriction measurements (5-300 K, 0-120 kOe) has been carried out. Our results support the suggested existence in this system of a coupled crystallographic-magnetic transition from a Gd sub 5 Ge sub 4 -type Pnma (antiferromagnetic) to a Gd sub 5 Si sub 4 -type Pnma (ferromagnetic) state. Strong magnetoelastic effects are observed at the field-induced first-order magnetic-martensitic transformation. A revised magnetic and crystallographic H- T phase diagram is proposed.

  5. Production of high-specific activity radionuclides using SM high-flux reactor

    International Nuclear Information System (INIS)

    Karelin, Ye.A.; Toporov, Yu.G.; Filimonov, V.T.; Vakhetov, F.Z.; Tarasov, V.A.; Kuznetsov, R.A.; Lebedev, V.M.; Andreev, O.I.; Melnik, M.I.; Gavrilov, V.D.

    1997-01-01

    The development of High Specific Activity (HSA) radionuclides production technologies is one of the directions of RIAR activity, and the high flux research reactor SM, having neutron flux density up to 2.10 15 cm -2 s 1 in a wide range of neutron spectra hardness, plays the principal role in this development. The use of a high-flux reactor for radionuclide production provides the following advantages: production of radionuclides with extremely high specific activity, decreasing of impurities content in irradiated targets (both radioactive and non-radioactive), cost-effective use of expensive isotopically enriched target materials. The production technologies of P-33, Gd-153, W-188, Ni-63, Fe-55,59, Sn-113,117m,119m, Sr- 89, applied in industry, nuclear medicine, research, etc, were developed by RIAR during the last 5-10 years. The research work included the development of calculation procedures for radionuclide reactor accumulation forecast, experimental determination of neutron cross-sections, the development of irradiated materials reprocessing procedures, isolation and purification of radionuclides. The principal results are reviewed in the paper. (authors)

  6. Peculiarities of component interaction in {l_brace}Gd, Er{r_brace}-V-Sn Ternary systems at 870 K and crystal structure of RV{sub 6}Sn{sub 6} stannides

    Energy Technology Data Exchange (ETDEWEB)

    Romaka, L., E-mail: romakal@franko.lviv.ua [Inorganic Chemistry Department, Ivan Franko Lviv National University, Kyryla and Mefodiya str. 6, 79005 Lviv (Ukraine); Stadnyk, Yu. [Inorganic Chemistry Department, Ivan Franko Lviv National University, Kyryla and Mefodiya str. 6, 79005 Lviv (Ukraine); Romaka, V.V. [Department of Materials Engineering and Applied Physics, Lviv Polytechnic National University, Ustyyanovycha Str. 5, 79013 Lviv (Ukraine); Demchenko, P.; Stadnyshyn, M.; Konyk, M. [Inorganic Chemistry Department, Ivan Franko Lviv National University, Kyryla and Mefodiya str. 6, 79005 Lviv (Ukraine)

    2011-09-08

    Highlights: > {l_brace}Gd, Er{r_brace}-V-Sn ternary systems at 870 K are characterized by formation of stannides with general compositions RV{sub 6}Sn{sub 6}. > Isostructural RV{sub 6}Sn{sub 6} compounds were also found with Y, Dy, Ho, Tm, and Lu. > The crystal structure of RV{sub 6}Sn{sub 6} compounds was determined by powder diffraction method. > Structural analysis showed that RV{sub 6}Sn{sub 6} compounds (R = Gd, Dy-Tm, Lu) are disordered; YV{sub 6}Sn{sub 6} is characterized by structure ordering. - Abstract: The phase equilibria in the Gd-V-Sn and Er-V-Sn ternary systems were studied at 870 K by means of X-ray and metallographic analyses in the whole concentration range. Both Gd-V-Sn and Er-V-Sn systems are characterized by formation of one ternary compound at investigated temperature, with stoichiometry RV{sub 6}Sn{sub 6} (SmMn{sub 6}Sn{sub 6}-type, space group P6/mmm, a = 0.55322(3) nm, c = 0.91949(7) nm for Gd, a = 0.55191(2) nm, c = 0.91869(8) nm for Er). Solubility of the third component in the binary compounds was not observed. Compounds with the SmMn{sub 6}Sn{sub 6}-type were also found with Dy, Ho, Tm, and Lu, while YV{sub 6}Sn{sub 6} compound crystallizes in HfFe{sub 6}Ge{sub 6} structure type. All investigated compounds are the first ternary stannides with rare earth elements and vanadium.

  7. An update on the thermodynamics of Ta2O5

    International Nuclear Information System (INIS)

    Jacob, K.T.; Shekhar, Chander; Waseda, Y.

    2009-01-01

    Using a solid-state electrochemical cell incorporating yttria-doped thoria (YDT) as the electrolyte and a mixture of (Mn + MnO) as the reference electrode, standard Gibbs free energy of formation of β-Ta 2 O 5 has been determined as a function of temperature in the range (1000 to 1300) K. The solid-state electrochemical cell used can be represented as (-)Pt,Ta+Ta 2 O 5 //(Y 2 O 3 )ThO 2 //Mn+MnO,Pt(+) Combining the reversible e.m.f. of the cell with recent data on the free energy of formation of MnO, standard Gibbs free energy of formation of Ta 2 O 5 from Ta metal and diatomic oxygen gas (O 2 ) in the temperature range (1000 to 1300) K is obtained: Δ f G 0 ±0.35/(kJ.mol -1 )=-2004.376+0.40445(T/K). Because of the significant solid solubility of oxygen in tantalum, a small correction for the activity of Ta in the metal phase in equilibrium with Ta 2 O 5 is applied. An analysis of the results obtained in this study and other free energy data reported in the literature by the 'third law' method suggests the need for refining data for Ta 2 O 5 reported in thermodynamic compilations. Used in the analysis is a revised value for standard entropy of Ta 2 O 5 based on more recent low-temperature heat capacity measurements. An improved set of thermodynamic properties of ditantalum pentoxide (Ta 2 O 5 ) are presented in the temperature range (298.15 to 2200) K.

  8. Thermodynamic calculation of Al-Gd and Al-Gd-Mg phase equilibria checked by key experiments

    International Nuclear Information System (INIS)

    Groebner, J.; Kevorkov, D.; Schmid-Fetzer, R.

    2001-01-01

    The binary Al-Gd and the ternary Al-Gd-Mg systems were calculated using the Calphad method. It is demonstrated that previous interpretation of ternary liquidus temperatures below 700 C must be related to other phase equilibria. The actual ternary liquidus temperatures are much higher, up to some 600 C above the previous interpretation in literature. They are widely governed by the high-melting compounds Al 2 Gd and Al 3 Gd with liquidus surfaces stretching far into the ternary system. A small number of key experiments in this work confirmed the calculated liquidus temperature and the phase relations. The available experimental data in literature fit excellently with the calculation in the binary Al-Gd system. In the ternary Al-Gd-Mg system, which is shown in several sections of the phase diagram, a good agreement can be observed too, considering the necessary reinterpretation of the liquidus temperatures suggested by Rokhlin et al. Ternary solubilities were not found experimentally. The ternary compound Al 4 GdMg (τ) forms in a ternary peritectic reaction at 761 C. (orig.)

  9. GdF Suez, the real energy champion;GdF Suez, le vrai champion de l'energie

    Energy Technology Data Exchange (ETDEWEB)

    Dupin, L.

    2010-09-15

    During summer 2010, France discovered that she owned a second energy giant, GdF Suez, ranked number two as a power producer just behind EdF, but world number one in the energy domain thanks to the taking over of International Power (UK) in 2010. Until now, GdF Suez and EdF were confronting with each other in a fair game, keeping their respective seizure on their historical monopolies, gas for GdF Suez and electricity for EdF. From now onward the two giants have started an open fight on all markets, with the exception of nuclear energy for which the French government continues to favour EdF. This paper recalls the main steps of the last 15 years of GdF Suez progress, from the Suez investment bank in 1995 to the merger with GdF in 2008 and the acquisition of International Power in 2010. Then it makes a comparative portrait of both GdF Suez and EdF energy groups with their respective advantages and, finally, it ends with an interview of G. Mestrallet, president of GdF Suez who explains the strategy of his group. (J.S.)

  10. CCSDS SM and C Mission Operations Interoperability Prototype

    Science.gov (United States)

    Lucord, Steven A.

    2010-01-01

    This slide presentation reviews the prototype of the Spacecraft Monitor and Control (SM&C) Operations for interoperability among other space agencies. This particular prototype uses the German Space Agency (DLR) to test the ideas for interagency coordination.

  11. Hydrogen-induced amorphization of SmFe{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Kubis, M.; Handstein, A.; Gebel, B.; Gutfleisch, O.; Mueller, K.-H.; Schultz, L. [Institut fuer Festkoerper- und Werkstofforschung Dresden e.V. (Germany). Inst. fuer Metallische Werkstoffe

    2000-07-01

    The hydrogen absorption behavior of SmFe{sub 3} (PuNi{sub 3}-type structure) was observed in the range from 0.05 to 4 MPa by differential scanning calorimetry. The structural changes were observed by X-ray diffraction measurements. For pressures below 0.8 MPa two exothermic reactions were found which are attributed (i) to the interstitial absorption and (ii) to the disproportionation into SmH{sub 2} and {alpha}-Fe. For higher hydrogen pressures, the second exothermic peak occured at significantly lower temperatures and splitted into two peaks. The first one was identified as the exothermic signal of the hydrogen-induced amorphization of the SmFe{sub 3} hydride. The second peak is caused by the precipitation of SmH{sub 2} and {alpha}-Fe from the amorphous material. (orig.)

  12. Synthesis and magnetic properties of SmOOH crystals

    Energy Technology Data Exchange (ETDEWEB)

    Samata, Hiroaki, E-mail: samata@maritime.kobe-u.ac.jp [Graduate School of Maritime Sciences, Kobe University, Fukaeminami, Higashinada, Kobe, Hyogo 658-0022 (Japan); Hanioka, Masashi [Graduate School of Maritime Sciences, Kobe University, Fukaeminami, Higashinada, Kobe, Hyogo 658-0022 (Japan); Ozawa, Tadashi C. [Materials Development Group, Superconducting Properties Unit, National Institute for Materials Science, Sengen, Tsukuba, Ibaraki 305-0047 (Japan)

    2016-01-15

    Samarium oxyhydroxide (SmOOH) crystals were synthesized using a flux method. The as-grown crystals were yellowish, transparent, and elongated with a maximum length of approximately 1.0 mm. SmOOH adopts a monoclinic structure in the space group P2{sub 1}/m with a=0.4356 nm, b=0.3766 nm, c=0.6139 nm, and β=108.464°. The magnetic susceptibility of the SmOOH crystals exhibited typical Van Vleck paramagnetism, and the experimental data at temperatures above 200 K were in close agreement with the calculated results using a spin-orbit coupling constant λ=443 K (308 cm{sup −1}). - Highlights: • SmOOH crystals were synthesized via flux method and characterized. • Magnetic susceptibilities above 200 K agreed with theoretical Van Vleck values. • Discrepancies were observed at lower temperatures based on the crystalline field.

  13. INTERACTION MODE BETWEEN METHYLENE BLUE-Sm(III ...

    African Journals Online (AJOL)

    Preferred Customer

    between methylene blue (MB)-Sm(III) complex and herring sperm DNA by using acridine orange .... the complex was recorded as KBr pellets on Spectrum One FTIR system (PE Company, USA), ..... mechanism of drugs and drug design.

  14. The simultaneous mass and energy evaporation (SM2E) model.

    Science.gov (United States)

    Choudhary, Rehan; Klauda, Jeffery B

    2016-01-01

    In this article, the Simultaneous Mass and Energy Evaporation (SM2E) model is presented. The SM2E model is based on theoretical models for mass and energy transfer. The theoretical models systematically under or over predicted at various flow conditions: laminar, transition, and turbulent. These models were harmonized with experimental measurements to eliminate systematic under or over predictions; a total of 113 measured evaporation rates were used. The SM2E model can be used to estimate evaporation rates for pure liquids as well as liquid mixtures at laminar, transition, and turbulent flow conditions. However, due to limited availability of evaporation data, the model has so far only been tested against data for pure liquids and binary mixtures. The model can take evaporative cooling into account and when the temperature of the evaporating liquid or liquid mixture is known (e.g., isothermal evaporation), the SM2E model reduces to a mass transfer-only model.

  15. 77 FR 64827 - Investigation Nos. 701-TA-402 and 731-TA-892 (Second Review); Honey From Argentina; Termination...

    Science.gov (United States)

    2012-10-23

    ... INTERNATIONAL TRADE COMMISSION Investigation Nos. 701-TA-402 and 731-TA-892 (Second Review); Honey... revocation of the countervailing duty order and antidumping duty order on imports of honey from Argentina would be likely to lead to continuation or recurrence of material injury. On September 21, 2012, the...

  16. High-pressure phases of Weyl semimetals NbP, NbAs, TaP, and TaAs

    Science.gov (United States)

    Guo, ZhaoPeng; Lu, PengChao; Chen, Tong; Wu, JueFei; Sun, Jian; Xing, DingYu

    2018-03-01

    In this study, we used the crystal structure search method and first-principles calculations to systematically explore the highpressure phase diagrams of the TaAs family (NbP, NbAs, TaP, and TaAs). Our calculation results show that NbAs and TaAs have similar phase diagrams, the same structural phase transition sequence I41 md→ P6¯ m2→ P21/ c→ Pm3¯ m, and slightly different transition pressures. The phase transition sequence of NbP and TaP differs somewhat from that of NbAs and TaAs, in which new structures emerge, such as the Cmcm structure in NbP and the Pmmn structure in TaP. Interestingly, we found that in the electronic structure of the high-pressure phase P6¯ m2-NbAs, there are coexistingWeyl points and triple degenerate points, similar to those found in high-pressure P6¯ m2-TaAs.

  17. Aligned, plasma sprayed SmCo5 deposits

    International Nuclear Information System (INIS)

    Kumar, K.; Das, D.

    1986-01-01

    Highly aligned SmCo 5 deposits were produced using plasma spraying. c-axis alignment, normal to the plane of the deposit, was achieved by depositing the Sm-Co alloys on steel substrates maintained at high temperatures. The substrates were heated by the plasma flame to obtain the high temperatures. The attainment of a range of substrate temperatures was made possible through control over the geometry of the substrate

  18. Faraday effect in Gd3Al5O12 and Gd3Ga5O12 rare earth garnets

    International Nuclear Information System (INIS)

    Valiev, U.V.; Klochkov, A.A.; Popov, A.I.; Sokolov, Y.B.

    1989-01-01

    The dispersion of the Faraday rotation of the garnets Gd 3 Ga 5 O 12 and Gd 3 Al 5 O 12 in the 440--700-nm region in the 85--295-K temperature interval and the spectral dependence of the Faraday effect in the garnets Y 3 Ga 5 O 12 and Y 3 Al 5 O 12 for wavelengths from 250 to 700 nm are investigated. The contributions to the Faraday rotation caused by the Gd 3+ ions and the diamagnetic lattice of the garnets are separated

  19. Improved sensitivity for W-band Gd(III)-Gd(III) and nitroxide-nitroxide DEER measurements with shaped pulses

    Science.gov (United States)

    Bahrenberg, Thorsten; Rosenski, Yael; Carmieli, Raanan; Zibzener, Koby; Qi, Mian; Frydman, Veronica; Godt, Adelheid; Goldfarb, Daniella; Feintuch, Akiva

    2017-10-01

    Chirp and shaped pulses have been recently shown to be highly advantageous for improving sensitivity in DEER (double electron-electron resonance, also called PELDOR) measurements due to their large excitation bandwidth. The implementation of such pulses for pulse EPR has become feasible due to the availability of arbitrary waveform generators (AWG) with high sampling rates to support pulse shaping for pulses with tens of nanoseconds duration. Here we present a setup for obtaining chirp pulses on our home-built W-band (95 GHz) spectrometer and demonstrate its performance on Gd(III)-Gd(III) and nitroxide-nitroxide DEER measurements. We carried out an extensive optimization procedure on two model systems, Gd(III)-PyMTA-spacer-Gd(III)-PyMTA (Gd-PyMTA ruler; zero-field splitting parameter (ZFS) D ∼ 1150 MHz) as well as nitroxide-spacer-nitroxide (nitroxide ruler) to evaluate the applicability of shaped pulses to Gd(III) complexes and nitroxides, which are two important classes of spin labels used in modern DEER/EPR experiments. We applied our findings to ubiquitin, doubly labeled with Gd-DOTA-monoamide (D ∼ 550 MHz) as a model for a system with a small ZFS. Our experiments were focused on the questions (i) what are the best conditions for positioning of the detection frequency, (ii) which pump pulse parameters (bandwidth, positioning in the spectrum, length) yield the best signal-to-noise ratio (SNR) improvements when compared to classical DEER, and (iii) how do the sample's spectral parameters influence the experiment. For the nitroxide ruler, we report an improvement of up to 1.9 in total SNR, while for the Gd-PyMTA ruler the improvement was 3.1-3.4 and for Gd-DOTA-monoamide labeled ubiquitin it was a factor of 1.8. Whereas for the Gd-PyMTA ruler the two setups pump on maximum and observe on maximum gave about the same improvement, for Gd-DOTA-monoamide a significant difference was found. In general the choice of the best set of parameters depends on the D

  20. ALnS2:RE (A=K, Rb; Ln=La, Gd, Lu, Y): New optical materials family

    International Nuclear Information System (INIS)

    Jarý, V.; Havlák, L.; Bárta, J.; Mihóková, E.; Buryi, M.; Nikl, M.

    2016-01-01

    In the presented review paper, new potentially interesting material family, RE-doped ternary sulfides ALnS 2 (RE=Ce, Pr, Sm, Eu, Tb, Tm; A=Rb, K; Ln=La, Gd, Lu, Y) is discussed. Their synthesis is described and the structural and optical properties, characterized by methods of X-ray diffraction, time-resolved luminescence spectroscopy and electron paramagnetic resonance, are summarized and reviewed especially with respect to the influence of their composition. All samples discussed were synthesized in the form of transparent crystalline hexagonal platelets by chemical reaction under the flow of hydrogen sulfide. Their luminescence characteristics, including absorption, radioluminescence, photoluminescence excitation and emission spectra and decay kinetics, were measured and evaluated in a broad temperature (8–800 K) and concentration (0.002–20% of dopants) range. The application potential of mentioned compounds in the field of white LED solid state lightings or X-ray phosphors is thoroughly discussed. - Highlights: • RE-doped ALnS 2 (A=K, Rb; Ln=La, Gd, Lu, Y) were synthesized. • Their optical characteristics are summarized. • Concentration and temperature dependences of luminescence features investigated. • EPR technique is employed to explain Eu 2+ incorporation into KLuS 2 host. • The application potential in white LED and X-ray phosphors is discussed.

  1. Electronic Structure of GdCuGe Intermetallic Compound

    Science.gov (United States)

    Lukoyanov, A. V.; Knyazev, Yu. V.; Kuz'min, Yu. I.

    2018-04-01

    The electronic structure of GdCuGe intermetallic compound has been studied. Spin-polarized energy spectrum calculations have been performed by the band method with allowance for strong electron correlations in the 4 f-shell of gadolinium ions. Antiferromagnetic ordering of GdCuGe at low temperatures has been obtained in a theoretical calculation, with the value of the effective magnetic moment of gadolinium ions reproduced in fair agreement with experimental data. The electronic density of states has been analyzed. An optical conductivity spectrum has been calculated for GdCuGe; it reveals specific features that are analogous to the ones discovered previously in the GdCuSi compound with a similar hexagonal structure.

  2. Neutronic analysis of Gd2O3 as burnable poison

    International Nuclear Information System (INIS)

    Lecot, C.A.

    1990-01-01

    For the reactors core design, the use of burnable poisons is one of the options for the control of in excess reactivity and the power form factor. As alternative procedures, the absorbing material may be included in pellets of an inert material or in fuel pellets. Besides, a cladding material and the locations of the fuel elements must be chosen for the first case. The CAREM reactor core design foresees the use of gadolinium oxide (Gd 2 O 3 ) as burnable poison. In this work, a comparative study was made, from the neutronic point of view, among the following alternatives for the poisons location: a) Gd 2 O 3 bars supports in alumina (Al 2 O 3 ), sheathed in steel; b) Gd 2 O 3 bars supports in alumina sheathed in Zry-4; c) Gd 2 O 3 in uranium dioxide (UO 2 ) fuel pellets. (Author) [es

  3. Evaluation of hypothetical (153)Gd source for use in brachytherapy.

    Science.gov (United States)

    Ghorbani, Mahdi; Behmadi, Marziyeh

    2016-01-01

    The purpose of this work is to evaluate the dosimetric parameters of a hypothetical (153)Gd source for use in brachytherapy and comparison of the dosimetric parameters with those of (192)Ir and (125)I sources. Dose rate constant, the radial dose function and the two dimensional (2D) anisotropy function data for the hypothetical (153)Gd source were obtained by simulation of the source using MCNPX code and then were compared with the corresponding data reported by Enger et al. A comprehensive comparison between this hypothetical source and a (192)Ir source with similar geometry and a (125)I source was performed as well. Excellent agreement was shown between the results of the two studies. Dose rate constant values for the hypothetical (153)Gd, (192)Ir, (125)I sources are 1.173 cGyh(-1) U(-1), 1.044 cGyh(-1) U(-1), 0.925 cGyh(-1) U(-1), respectively. Radial dose function for the hypothetical (153)Gd source has an increasing trend, while (192)Ir has more uniform and (125)I has more rapidly falling off radial dose functions. 2D anisotropy functions for these three sources indicate that, except at 0.5 cm distance, (192)Ir and (125)I have more isotropic trends as compared to the (153)Gd source. A more uniform radial dose function, and 2D anisotropy functions with more isotropy, a much higher specific activity are advantages of (192)Ir source over (153)Gd. However, a longer half-life of (153)Gd source compared to the other two sources, and lower energy of the source with respect to (192)Ir are advantages of using (153)Gd in brachytherapy versus (192)Ir source.

  4. GdF in Hungary: the East in progress

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    After Germany and the Czech Republic, Gaz de France (GdF) has decided to export its know-how and technologies about natural gas into Hungary. Thanks to the Hungarian privatization program started in 1995, GdF could obtain the major participation in the Degaz and Egaz companies, two out of the five local distribution companies, and controls 22% of the natural gas distribution in Hungary. (J.S.)

  5. Single step synthesis of GdAlO3 powder

    International Nuclear Information System (INIS)

    Sinha, Amit; Nair, S.R.; Sinha, P.K.

    2011-01-01

    Research highlights: → First report on direct formation of GdAlO 3 powder using a novel combustion process. → Study of combustion characteristics of Gd(NO 3 ) 3 and Al(NO 3 ) 3 towards three fuels. → Preparation of highly sinterable GdAlO 3 powders through fuel-mixture approach. → Significant reduction in energy consumption for production of GdAlO 3 sintered body. - Abstract: A novel method for preparation of nano-crystalline gadolinium aluminate (GdAlO 3 ) powder, based on combustion synthesis, is reported. It was observed that aluminium nitrate and gadolinium nitrate exhibit different combustion characteristics with respect to urea, glycine and β-alanine. While urea was proven to be a suitable fuel for direct formation of crystalline α-Al 2 O 3 from its nitrate, glycine and β-alanine are suitable fuels for gadolinium nitrate for preparation of its oxide after combustion reaction. Based on the observed chemical characteristics of gadolinium and aluminium nitrates with respect to above mentioned fuels for the combustion reaction, the fuel mixture composition could be predicted that could lead to phase pure perovskite GdAlO 3 directly after the combustion reaction without any subsequent calcination step. The use of single fuel, on the other hand, leads to formation of amorphous precursor powders that call for subsequent calcination for the formation of crystalline GdAlO 3 . The powders produced directly after combustion reactions using fuel mixtures were found to be highly sinterable. The sintering of the powders at 1550 o C for 4 h resulted in GdAlO 3 with sintered density of more than 95%. T.D.

  6. Contribution to the WWER-440 Gd-assembly evolution

    International Nuclear Information System (INIS)

    Cudrnak, P.; Darilek, P.; Necas, V.

    2009-01-01

    Development activities, presented in the paper, contribute to the evolution of gadolinium fuel for the WWER-440 reactors. Short overview of existing and already proposed Gd-assemblies is given. Two new assembly types with improved features are described. Multiplication coefficients and pin power peaking factors of all mentioned gadolinium assemblies are compared. Animations of power distribution behaviour in selected Gd-assemblies are shown. (Authors)

  7. Polarized single crystal neutron diffraction study of the zero-magnetization ferromagnet Sm1 -xGdxAl2 (x =0.024 )

    Science.gov (United States)

    Chatterji, T.; Stunault, A.; Brown, P. J.

    2018-02-01

    We have determined the temperature evolution of the spin and orbital moments in the zero-magnetization ferromagnet Sm1 -xGdxAl2 (x = 0.024) by combining polarized and unpolarized single crystal neutron diffraction data. The sensitivity of the polarized neutron technique has allowed the moment values to be determined with a precision of ≈0.1 μB . Our results clearly demonstrate that, when magnetized by a field of 8 T, the spin and orbital moments in Sm1 -xGdxAl2 are oppositely directed, so that the net magnetization is very small. Below 60 K the contributions from spin and orbital motions are both about 2 μB , with that due to orbital motion being slightly larger than that due to spin. Between 60 and 65 K the contributions of each to the magnetization fall rapidly and change sign at Tcomp ≈67 K , above which the aligned moments recover but with the orbital magnetization still slightly higher than the spin one. These results imply that above Tcomp the small resultant magnetization of the Sm3 + ion is oppositely directed to the magnetizing field. It is suggested that this anomaly is due to polarization of conduction electron spin associated with the doping Gd3 + ions.

  8. Electron impact excitation of Gd XXXVII

    Energy Technology Data Exchange (ETDEWEB)

    Aggarwal, K.M.; Keenan, F.P. [Dept. of Pure and Applied Physics, Queen' s Univ., Belfast (United Kingdom); Norrington, P.H.; Bell, K.L. [Dept of Applied Maths. and Theoretical Physics, Queen' s Univ., Belfast (United Kingdom); Pert, G.J. [Dept. of Physics, York Univ., York (United Kingdom); Rose, S.J. [Plasma Physics Group, Rutherford Appleton Lab., Oxon (United Kingdom)

    2000-01-01

    Energy levels and radiative rates for transitions among the 107 fine-structure levels belonging to the (1s{sup 2}2s{sup 2}2p{sup 6}) 3s{sup 2}3p{sup 6}3d{sup 10}, 3s{sup 2}3p{sup 6}3d{sup 9}4l, 3s{sup 2}3p{sup 5}3d{sup 10}4l, and 3s3p{sup 6}3d{sup 10}4l configurations of Ni-like Gd XXXVII have been calculated using the GRASP code. The collision strengths have also been computed but among the lowest 59 levels only, at 4 representative energies of 200, 400, 600 and 800 Ryd, using the Dirac Atomic R-matrix code. Detailed calculations for collision strengths and rate coefficients are in progress. (author)

  9. Localization and screening in GdNi alloy films

    Energy Technology Data Exchange (ETDEWEB)

    Wu, N.; Dowben, P.A. [Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Theodore Jorgenson Hall, 855 North 16th Street, Lincoln, Nebraska 68588-0299 (United States); LaGraffe, D. [Office of Proliferation Detection NA-22, National Nuclear Security Administration, US Department of Energy, 1000 Independence Avenue SW, Washington, DC 20585 (United States); Yakovkin, I.N. [National Academy of Science of Ukraine, Institute of Physics, Prospect Nauki 46, 03028 Kiev (Ukraine)

    2011-05-15

    Gd/Ni compounds with different Gd concentration have been investigated with constant initial state spectroscopy (CIS) of photoemission utilizing the light of synchrotron radiation. The photoemission cross-sections of Gd 5d and 4f states show a strong resonance in CIS spectra at the Gd 5p absorption edge. The screenings of Gd ions by Ni 3d conduction electrons results in a dramatic suppression of the 5p{sup 6}4f{sup 7}5d{sup 1}6s{sup 2} to 5p{sup 5}4f{sup 7}5d{sup 2}6s{sup 2} resonant enhancement of photoemission valence band intensities. This decrease in the super-Coster-Kronig photoemission resonant enhancement of the valence band can be related to the hybridized Gd 5d and Ni 3d bands near the Fermi level, consistent with performed first-principles calculations of local densities of states. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Radiation damage in CaF2: Gd

    International Nuclear Information System (INIS)

    Prado, L.

    1979-01-01

    Calcium fluoride crystals doped with Gd 3+ at four different concentrations were irradiated at room temperature. The damage produced by radiation and the primary and secondary effects as well were studied by optical spectroscopy. The increase in optical absorption (with loss of transparency) varied from sample as a function of concentration and dose. The coloration curves showed an evolution from two to three radiation damage steps when going from a pure to the most Gd 3+ concentrated sample. The obtained spectra were analysed at characteristic wave lenghts of electronic defects (photochromic centers, F and its aggregates) and of Gd 3+ and Gd 2+ defects. As a result of the radiation damage the valence change (Gd 3+ →Gd 2+ ) and its reversible character under thermal activation were directly observed. These effects were correlated with other observed effects such as the room temperature luminescence after the irradiation ceased. The non radiative F centers formation from the interaction of holes and photochromic centers was also observed and analysed. A thermal activation study of the several defects responsible for the different absorption bands was made. Values of activation energies were obtained as expected for the kind of defects involved in these processes [pt

  11. A new entry in GdNCT. The nanodosimetry

    International Nuclear Information System (INIS)

    Cerullo, Nicola; Bufalino, Domenico; Esposito, Juan

    2006-01-01

    The GdNCT is a recently proposed therapy, mainly based on the action of Auger and IC electrons, generated by 157 Gd after neutron activation. The energy carried out by these electrons is limited to about 1% of total energy of the reaction, but due to high electron LET, if the emitter is bound to DNA, their action is very effective. Some Gd compounds have the property to be bound to DNA. Therefore the evaluation of the DNA damage caused by the Gd-emitted electrons is a key issue. The DNA damage is due to almost double strand breaks (DSB) in the DNA double helix chain. The dimensions concerned are of the order of 2 to 3 nm. Therefore, in the study of GdNCT, besides macro and micro, we must use the new 'nanodosimetry', based on particle interactions in the nanometric sites. A general review on GdNCT state of the art and on the nanometric Monte Carlo computing techniques, applied to a DNA model, is here presented. (author)

  12. Investigation of nanocrystalline Gd films loaded with hydrogen

    KAUST Repository

    Hruška, Petr; Čí žek, Jakub; Dobroň, Patrik; Anwand, Wolfgang; Mü cklich, Arndt; Gemma, Ryota; Wagner, Stefan; Uchida, Helmut; Pundt, Astrid

    2015-01-01

    The present work reports on microstructure studies of hydrogen-loaded nanocrystalline Gd films prepared by cold cathode beam sputtering on sapphire (112¯0) substrates. The Gd films were electrochemically step-by-step charged with hydrogen and the structural development with increasing concentration of absorbed hydrogen was studied by transmission electron microscopy and in-situ   X-ray diffraction using synchrotron radiation. The relaxation of hydrogen-induced stresses was examined by acoustic emission measurements. In the low concentration range absorbed hydrogen occupies preferentially vacancy-like defects at GBs typical for nanocrystalline films. With increasing hydrogen concentration hydrogen starts to occupy interstitial sites. At the solid solution limit the grains gradually transform into the ββ-phase (GdH2). Finally at high hydrogen concentrations xH>2.0xH>2.0 H/Gd, the film structure becomes almost completely amorphous. Contrary to bulk Gd specimens, the formation of the γγ-phase (GdH3) was not observed in this work.

  13. Magnetism of Ta dichalcogenide monolayers tuned by strain and hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Manchanda, Priyanka; Sellmyer, D. J.; Skomski, Ralph [Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588 (United States); Sharma, Vinit [Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269 (United States); Yu, Hongbin [School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States)

    2015-07-20

    The effects of strain and hydrogenation on the electronic, magnetic, and optical properties of monolayers of Ta based dichalcogenides (TaX{sub 2}; X = S, Se, and Te) are investigated using density-functional theory. We predict a complex scenario of strain-dependent magnetic phase transitions involving paramagnetic, ferromagnetic, and modulated antiferromagnetic states. Covering one of the two chalcogenide surfaces with hydrogen switches the antiferromagnetic/nonmagnetic TaX{sub 2} monolayers to a semiconductor, and the optical behavior strongly depends on strain and hydrogenation. Our research opens pathways towards the manipulation of magnetic as well as optical properties for future spintronics and optoelectronics applications.

  14. Hyperfine interaction studies of the perovskite oxides of the type RCrO3 (R = Gd, Tb e Dy)

    International Nuclear Information System (INIS)

    Silva, Renilson Adriano da

    2009-01-01

    ABO 3 perovskite oxides have ideal cubic structure, however, some distortions in this type of structure may induce changes from cubic to orthorhombic or rhombroedric symmetry. The larger atoms A are located at the center of a cube, the B atoms are on 8 vertices and oxygen atoms occupy 12 positions in the middle of each side of the cube. Distortions in this structure may lead to new magnetic and electrical properties, with great scientific and technological interest. In this work RCrO 3 (R = Gd, Tb, Dγ) compounds (also known as orthocromites) were studied. The samples were produced by means of sol-gel chemical procedure and analyzed by X-Ray Diffraction. The results showed a single phase with Pbnm space group. The perturbed gamma-gamma angular correlation (PAC) measurements were carried out using 181 Hf( 181 Ta) and 111 In( 111 Cd) nuclear probes, which substitute 'A' and 'B' positions respectively. The probe nuclei were introduced in the samples during the chemical procedures for preparation. One of the objectives of this work's was to study the hyperfine magnetic field and its variation as a function of temperature, crystallographic structure as well as the antiferromagnetic transition temperature (T N ). The PAC Measurements were carried out in the temperature range of 20 to 300 K for R = Gd, Tb and 20 to 800 K in the case of R = Dγ from. Electric field gradient was also measured as a function of temperature. It was possible to observe the expected transition as well as the alignment of Cr spins, as found in literature. The Neel temperatures (TN) for investigated samples are ∼170 K, ∼164 K and ∼148 K for GdCrO 3 , TbCrO 3 and DyCrO 3 respectively. (author)

  15. Comparison of two brain tumor-localizing MRI agent. GD-BOPTA and GD-DTPA. MRI and ICP study of rat brain tumor model

    International Nuclear Information System (INIS)

    Zhang, T.; Matsumura, A.; Yamamoto, T.; Yoshida, F.; Nose, T.

    2000-01-01

    In this study, we compared the behavior of Gd-BOPTA as a brain tumor selective contrast agent with Gd-DTPA in a common dose of 0.1 mmol/kg. We performed a MRI study using those two agent as contrast material, and we measured tissue Gd-concentrations by ICP-AES. As a result, Gd-BOPTA showed a better MRI enhancement in brain tumor. ICP showed significantly greater uptake of Gd-BOPTA in tumor samples, at all time course peaked at 5 minutes after administration, Gd being retained for a longer time in brain tumor till 2 hours, without rapid elimination as Gd-DTPA. We conclude that Gd-BOPTA is a new useful contrast material for MR imaging in brain tumor and an effective absorption agent for neutron capture therapy for further research. (author)

  16. Study on the high-spin states and signature inversion of odd-odd nucleus 170Ta

    International Nuclear Information System (INIS)

    Deng Fuguo; Zhou Hongyu; Sun Huibin; Lu Jingbin; Zhao Guangyi; Yin Lichang; Liu Yunzuo

    2002-01-01

    The high-spin states of odd-odd nucleus 170 Ta were populated via the 155 Gd( 19 F, 4n) 170 Ta reaction with beam energy of 97 MeV provided by the HI-13 tandem accelerator of China Institute of Atomic Energy. Three rotational bands have been pushed to higher spin states and the signature inversion point of the semidecoupled band based on the πh 9/2 1/2 - [541] direct x νi 13/2 configuration has been observed to be 19.5 ℎ. The systematic features of the signature inversion in semidecoupled bands in odd-odd rare earth nuclei were summarized. The systematic differences of signature inversion, especially the difference in the energy splitting between the yrast hands and the semidecoupled hands in odd-odd rare earth nuclei are pointed out and discussed for the first time. It seems that p-n interaction between the odd proton and odd neutron in the odd-odd nuclei plays an important role

  17. Rotating disk atomization of Gd and Gd-Y for hydrogen liquefaction via magnetocaloric cooling

    Energy Technology Data Exchange (ETDEWEB)

    Slinger, Tyler [Iowa State Univ., Ames, IA (United States)

    2016-12-17

    In order to enable liquid hydrogen fuel cell technologies for vehicles the cost of hydrogen liquefaction should be lowered. The current method of hydrogen liquefaction is the Claude cycle that has a figure of merit (FOM) of 0.3-0.35. New magnetocaloric hydrogen liquefaction devices have been proposed with a FOM>0.5, which is a significant improvement. A significant hurdle to realizing these devices is the synthesis of spherical rare earth based alloy powders of 200μm in diameter. In this study a centrifugal atomization method that used a rotating disk with a rotating oil quench bath was developed to make gadolinium and gadolinium-yttrium spheres. The composition of the spherical powders included pure Gd and Gd0.91Y0.09. The effect of atomization parameters, such as superheat, melt properties, disk shape, disk speed, and melt system materials and design, were investigated on the size distribution and morphology of the resulting spheres. The carbon, nitrogen, and oxygen impurity levels also were analyzed and compared with the magnetic performance of the alloys. The magnetic properties of the charge material as well as the resulting powders were measured using a vibrating sample magnetometer. The saturation magnetization and Curie temperature were the target properties for the resulting spheres. These values were compared with measurements taken on the charge material in order to investigate the effect of atomization processing on the alloys.

  18. Morphological stability of Sm123 superconductor during peritectic solidification from Sm211 + L mixture

    International Nuclear Information System (INIS)

    Sumida, Masaki; Shiohara, Yuh; Umeda, Takateru

    2000-01-01

    The interface stability of the Sm 123 superconductor was analyzed in accordance with the constitutional undercooling criterion. As the single-crystal growth of the 123 phase is largely dependent on the growth-interface stability, a quantitative analysis was very much required. From this analysis, it was clarified that the constitutional undercooling must exist in the liquid when the 123 growth interface comes close to a 211 particle during the peritectic solidification. It was also predicted that the larger 211 particle radius, smaller volume fraction of the 211 particles, larger growth rate, or smaller imposed temperature gradient would cause easy occurrence of the constitutional undercooling ahead of the 123 growth interface. Taking into account the nucleation at the L/211 interface just ahead of the 123 growth front due to the constitutional undercooling, the transition of 123 growth from a planar-interface morphology to an equiaxed blocky morphology was investigated quantitatively and qualitatively

  19. Role of SM22 in the differential regulation of phasic vs. tonic smooth muscle

    Science.gov (United States)

    Ali, Mehboob

    2015-01-01

    Preliminary proteomics studies between tonic vs. phasic smooth muscles identified three distinct protein spots identified to be those of transgelin (SM22). The latter was found to be distinctly downregulated in the internal anal sphincter (IAS) vs. rectal smooth muscle (RSM) SMC. The major focus of the present studies was to examine the differential molecular control mechanisms by SM22 in the functionality of truly tonic smooth muscle of the IAS vs. the adjoining phasic smooth muscle of the RSM. We monitored SMC lengths before and after incubation with pFLAG-SM22 (for SM22 overexpression), and SM22 small-interfering RNA. pFLAG-SM22 caused concentration-dependent and significantly greater relaxation in the IAS vs. the RSM SMCs. Conversely, temporary silencing of SM22 caused contraction in both types of the SMCs. Further studies revealed a significant reverse relationship between the levels of SM22 phosphorylation and the amount of SM22-actin binding in the IAS and RSM SMC. Data showed higher phospho-SM22 levels and decreased SM22-actin binding in the IAS, and reverse to be the case in the RSM SMCs. Experiments determining the mechanism for SM22 phosphorylation in these smooth muscles revealed that Y-27632 (Rho kinase inhibitor) but not Gö-6850 (protein kinase C inhibitor) caused concentration-dependent decreased phosphorylation of SM22. We speculate that SM22 plays an important role in the regulation of basal tone via Rho kinase-induced phosphorylation of SM22. PMID:25617350

  20. Ganglioside GD2 in reception and transduction of cell death signal in tumor cells

    International Nuclear Information System (INIS)

    Doronin, Igor I; Vishnyakova, Polina A; Kholodenko, Irina V; Ponomarev, Eugene D; Ryazantsev, Dmitry Y; Molotkovskaya, Irina M; Kholodenko, Roman V

    2014-01-01

    Ganglioside GD2 is expressed on plasma membranes of various types of malignant cells. One of the most promising approaches for cancer immunotherapy is the treatment with monoclonal antibodies recognizing tumor-associated markers such as ganglioside GD2. It is considered that major mechanisms of anticancer activity of anti-GD2 antibodies are complement-dependent cytotoxicity and/or antibody-mediated cellular cytotoxicity. At the same time, several studies suggested that anti-GD2 antibodies are capable of direct induction of cell death of number of tumor cell lines, but it has not been investigated in details. In this study we investigated the functional role of ganglioside GD2 in the induction of cell death of multiple tumor cell lines by using GD2-specific monoclonal antibodies. Expression of GD2 on different tumor cell lines was analyzed by flow cytometry using anti-GD2 antibodies. By using HPTLC followed by densitometric analysis we measured the amount of ganglioside GD2 in total ganglioside fractions isolated from tumor cell lines. An MTT assay was performed to assess viability of GD2-positive and -negative tumor cell lines treated with anti-GD2 mAbs. Cross-reactivity of anti-GD2 mAbs with other gangliosides or other surface molecules was investigated by ELISA and flow cytometry. Inhibition of GD2 expression was achieved by using of inhibitor for ganglioside synthesis PDMP and/or siRNA for GM2/GD2 and GD3 synthases. Anti-GD2 mAbs effectively induced non-classical cell death that combined features of both apoptosis and necrosis in GD2-positive tumor cells and did not affect GD2-negative tumors. Anti-GD2 mAbs directly induced cell death, which included alteration of mitochondrial membrane potential, induction of apoptotic volume decrease and cell membrane permeability. This cytotoxic effect was mediated exclusively by specific binding of anti-GD2 antibodies with ganglioside GD2 but not with other molecules. Moreover, the level of GD2 expression correlated with

  1. Higher-order scalar interactions and SM vacuum stability

    Energy Technology Data Exchange (ETDEWEB)

    Lalak, Zygmunt; Lewicki, Marek; Olszewski, Paweł [Institute of Theoretical Physics, Faculty of Physics, University of Warsawul. Hoża 69, Warsaw (Poland)

    2014-05-26

    Investigation of the structure of the Standard Model effective potential at very large field strengths opens a window towards new phenomena and can reveal properties of the UV completion of the SM. The map of the lifetimes of the vacua of the SM enhanced by nonrenormalizable scalar couplings has been compiled to show how new interactions modify stability of the electroweak vacuum. Whereas it is possible to stabilize the SM by adding Planck scale suppressed interactions and taking into account running of the new couplings, the generic effect is shortening the lifetime and hence further destabilisation of the SM electroweak vacuum. These findings have been illustrated with phase diagrams of modified SM-like models. It has been demonstrated that stabilisation can be achieved by lowering the suppression scale of higher order operators while picking up such combinations of new couplings, which do not deepen the new minima of the potential. Our results show the dependence of the lifetime of the electroweak minimum on the magnitude of the new couplings, including cases with very small couplings (which means very large effective suppression scale) and couplings vastly different in magnitude (which corresponds to two different suppression scales)

  2. 75 FR 66794 - Notice of Affirmative Determination Regarding Application for Reconsideration: TA-W-71,572...

    Science.gov (United States)

    2010-10-29

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-71,572; TA-W-71,572A; TA-W-71,572B; TA-W-71,572C] Notice of Affirmative Determination Regarding Application for Reconsideration: TA-W...; TA-W-71,572A, Severstal Wheeling, Inc., a Subsidiary of Severstal North America, Inc., Yorkville, OH...

  3. Modelling the mechanical behaviour of heterogeneous Ta/TA6V welded joints: behaviour and failure criteria; Modelisation du comportement mecanique des liaisons soudees heterogenes Ta/TA6V: comportement et critere de rupture

    Energy Technology Data Exchange (ETDEWEB)

    Paris, Th

    2008-12-15

    As laser welding of two different materials (heterogeneous welding) leads to a joint having a characteristic size close to the millimetre, i.e. much smaller than that of a structure, and as such a junction displays completely different mechanical properties because of the metallurgical transformations induced by intense thermal loading, the aim of this research thesis is to develop a behaviour model, flexible and robust enough, to represent all together the mechanical behaviours of the Ta, the TA6V and the melted zone. This model must be able to take plasticity and visco-plasticity into account, and also to provide a failure criterion through damage mechanics and its coupling with the behaviour. The author first reports the experimental characterization of the base materials (Ta and TA6V) by using tensile tests under different strain rates and different directions, relaxation tests and fatigue shear tests. He also characterizes the melted zone by describing the influence of a thermal treatment (induced by welding) on the formation of the melted zone, and by using different tests: four point bending on notched specimens, nano-indentation test, and longitudinal tensile test. In a second part, the author develops the model within the framework of continuum thermodynamics, and explores the numerical issues. The last part deals with the validation of the model for the concerned materials (Ta and TA6V) and melted zone.

  4. Ageing effect on the magnetocaloric properties of Gd, Gd5Si1.9Ge2.1 and on the eutectic composition Gd75Cd25

    International Nuclear Information System (INIS)

    Canepa, F; Cirafici, S; Napoletano, M; Cimberle, M R; Tagliafico, L; Scarpa, F

    2008-01-01

    The ageing effects due to the interaction with typical working fluids (water and air) of magnetic refrigerant materials have been analysed for up to one year. Among the many compounds reported to exhibit a sufficiently high magnetocaloric effect, we decided to artificially age Gd, which represents the first choice high magnetocaloric element, Gd 5 Si 1.9 Ge 2.1 , belonging to the series Gd 5 (Si x Ge 4-x ) 4 which for x ∼ 0.5 displays a giant magnetocaloric effect, and finally, the eutectic Gd 75 Cd 25 alloy, presenting an almost constant adiabatic temperature rise in an interesting temperature span (260-280 K). Magnetothermal results give evidence that corrosion and corrosion/erosion processes take place with different results on the refrigerant properties of all the materials. The adiabatic temperature rise is strongly reduced due to surface oxidation which lowers thermal conduction while the effect on the refrigerant capacity Q is definitely smaller. The effects of corrosion/erosion processes are confirmed by quantitative chemical analysis performed on the refrigerant fluid before and after the ageing process. Employing working fluids with a reduced corrosive effect but with comparable thermal properties may be a viable way of avoiding corrosion damage; alternatively the use of additives to decrease the corrosive properties of the fluids is strongly suggested

  5. Prism inside. Spectroscopic and magnetic properties of the lanthanide(III) chloride oxidotungstates(VI) Ln{sub 3}Cl{sub 3}[WO{sub 6}] (Ln = La - Nd, Sm - Tb)

    Energy Technology Data Exchange (ETDEWEB)

    Dorn, Katharina V.; Blaschkowski, Bjoern; Hartenbach, Ingo [Institute for Inorganic Chemistry, University of Stuttgart (Germany); Foerg, Katharina; Netzsch, Philip; Hoeppe, Henning A. [Institute for Physics, University of Augsburg (Germany)

    2017-11-17

    The lanthanide(III) chloride oxidotungstates(VI) with the formula Ln{sub 3}Cl{sub 3}[WO{sub 6}] for Ln = La - Nd, Sm - Tb were synthesized by solid-state reactions utilizing the respective lanthanide trichloride, lanthanide sesquioxide (where available), and tungsten trioxide together with lithium chloride as flux. The title compounds crystallize hexagonally in space group P6{sub 3}/m (no. 176, a = 941-909, c = 543-525 pm, Z = 2). The structures comprise crystallographically unique Ln{sup 3+} cations surrounded by six O{sup 2-} and four Cl{sup -} anions (C.N. = 10) forming distorted tetracapped trigonal prisms as well as rather uncommon trigonal prismatic [WO{sub 6}]{sup 6-} units, whose edges are coordinated by nine Ln{sup 3+} cations. Thus, a {sup 3}{sub ∞}{([WO_6]Ln"e_9_/_3)"3"+} framework (e = edge-sharing) is created, which contains tube-shaped channels along [001] lined with chloride anions. To elucidate the spectroscopic and magnetic properties of the obtained pure phase samples, single-crystal Raman (for Ln = La - Nd, Sm-Tb), diffuse reflectance (for Ln = La, Pr, Nd, Gd), and luminescence spectroscopy (for bulk Ln{sub 3}Cl{sub 3}[WO{sub 6}] (Ln = La, Eu, Gd, Tb) and Eu{sup 3+}- or Tb{sup 3+}-doped derivatives of La{sub 3}Cl{sub 3}[WO{sub 6}] and Gd{sub 3}Cl{sub 3}[WO{sub 6}], respectively) were performed and their temperature-dependent magnetic moments (for Ln = Pr, Nd, Gd) were determined. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Phase equilibrium of the Gd-Fe-Co system at 873 K

    International Nuclear Information System (INIS)

    Huang Jinli; Zhong Haichang; Xia Xiuwen; He Wei; Zhu Jinming; Deng Jianqiu; Zhuang Yinghong

    2009-01-01

    Phase equilibrium of the ternary Gd-Fe-Co system at 873 K was investigated by using X-ray diffraction technique, electron probe microanalysis, metallographic analysis and differential thermal analysis. The 873 K isothermal section of the phase diagram of the Gd-Fe-Co ternary system consists of 11 single-phase regions, 16 two-phase regions and 6 three-phase regions. Three pairs of corresponding compounds of Gd-Co and Gd-Fe, i.e., Gd 2 Co 17 and Gd 2 Fe 17 , GdCo 3 and GdFe 3 , GdCo 2 and GdFe 2 , form a continuous series of solid solution. The compound Gd 2 Co 7-x Fe x was found to have a broad solubility range from 0 to 31 at.% Fe. The maximum solubility of Co in Gd 6 Fe 23 is about 7 at.% Co. At 873 K, the maximum solubilities of Fe in Gd 3 Co and Gd 4 Co 3 are about 3 and 1 at.% Fe, respectively. No ternary compound was found in all ternary alloy samples

  7. Synergistic effect of Al and Gd on enhancement of mechanical properties of magnesium alloys

    Directory of Open Access Journals (Sweden)

    Bita Pourbahari

    2017-04-01

    Full Text Available The effect of Gd/Al ratio on the properties of as-cast Mg-Gd-Al-Zn alloys was investigated by changing the chemical composition from that of AZ61 to GZ61. At the ratio of 1, the Al2Gd phase becomes predominant and Mg17Al12 is hardly seen in the microstructure. As a potent inoculant, the Al2Gd phase resulted in intense grain refinement and enhancement of strength, ductility and toughness. For instance, the tensile strength and elongation to failure of Mg-3Gd-3Al-1Zn alloy were enhanced by ~4% and 180% compared with those of AZ61 alloy, respectively. However, at high Gd/Al ratios, the Al2Gd phase was replaced by (Mg,Al3Gd and Mg5Gd phases and very large grain sizes were achieved, which led to poor tensile properties and the appearance of cleavage facets on the fracture surfaces. Therefore, it can be deduced that the presence of Gd and Al, in appropriate amounts to reach Gd/Al ratio of ~ 1, is required for the achievement of grain refinement, good ductility, high strength, and the appearance of ductile fracture surfaces in the Mg-Gd-Al-Zn system. Conclusively, the Mg-Gd-Al-Zn alloys can be considered as a new class of structural magnesium alloy and it is superior to both AZ (Mg-Al-Zn and GZ (Mg-Gd-Zn series of alloys.

  8. Crystallization and atomic diffusion behavior of high coercive Ta/Nd-Fe-B/Ta-based permanent magnetic thin film

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Na; Zhang, Xiao; You, Caiyin; Fu, Huarui [Xi' an University of Technology, School of Materials Science and Engineering, Xi' an (China); Shen, Qianlong [Logistics University of People' s Armed Police Force, Tianjin (China)

    2017-06-15

    A high coercivity of about 20.4 kOe was obtained through post-annealing the sputtered Ta/Nd-Fe-B/Ta-based permanent magnetic thin films. Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses were performed to investigate the crystallization and atomic diffusion behaviors during post-annealing. The results show that the buffer and capping Ta layers prefered to intermix with Fe and B atoms, and Nd tends to be combined with O atoms. The preferred atomic combination caused the appearance of the soft magnetic phase of Fe-Ta-B, resulting in a kink of the second quadratic magnetic hysteresis loop. The preferred atomic diffusion and phase formation of the thin films were well explained in terms of the formation enthalpy of the various compounds. (orig.)

  9. Pre-Test Analysis Predictions for the Shell Buckling Knockdown Factor Checkout Tests - TA01 and TA02

    Science.gov (United States)

    Thornburgh, Robert P.; Hilburger, Mark W.

    2011-01-01

    This report summarizes the pre-test analysis predictions for the SBKF-P2-CYL-TA01 and SBKF-P2-CYL-TA02 shell buckling tests conducted at the Marshall Space Flight Center (MSFC) in support of the Shell Buckling Knockdown Factor (SBKF) Project, NASA Engineering and Safety Center (NESC) Assessment. The test article (TA) is an 8-foot-diameter aluminum-lithium (Al-Li) orthogrid cylindrical shell with similar design features as that of the proposed Ares-I and Ares-V barrel structures. In support of the testing effort, detailed structural analyses were conducted and the results were used to monitor the behavior of the TA during the testing. A summary of predicted results for each of the five load sequences is presented herein.

  10. Tuning the effective parameters in (Ta/Cu/[Ni/Co]x/Ta) multilayers with perpendicular magnetic anisotropy

    Science.gov (United States)

    Ayareh, Zohreh; Moradi, Mehrdad; Mahmoodi, Saman

    2018-06-01

    In this paper, we report perpendicular magnetic anisotropy (PMA) in a (Ta/Cu/[Ni/Co]x/Ta) multilayers structure. These typical structures usually include a multilayer of ferromagnetic and transition metal thin films. Usually, magnetic anisotropy is characterized by magnetization loops determined by magnetometer or magneto-optical Kerr effect (MOKE). The interface between ferromagnetic and metallic layers plays an important role in magnetic anisotropy evolution from out-of-plane to in-plane in (Ta/Cu/[Ni/Co]/Ta) structure. Obtained results from MOKE and magnetometry of these samples show that they have different easy axes due to change in thickness of Cu as spacer layer and difference in number of repetition of [Ni/Co] stacks.

  11. Dilatometric and dielectric behaviour of Sm modified PCT ceramics

    International Nuclear Information System (INIS)

    Singh, Sarabjit; Thakur, O.P.; Prakash, Chandra; Raina, K.K.

    2005-01-01

    Samarium modified PCT ceramics with composition (Pb 0.76-x Sm x Ca 0.24 )(Ti 0.98 Mn 0.02 )O 3 ; x=0-0.08 in steps of 0.02 were prepared by conventional mixed-oxide method. Detailed dilatometric studies were carried out for green specimens in order to study sintering behaviour. Change in the dilatometric behaviour is correlated with the XRD results of powders calcined at different temperatures. Dielectric constant was observed to increase with increasing Sm concentration, which has been attributed to reduced tetragonality and better densification on Sm substitution. SEM micrographs have revealed the grain size of the samples. Ferroelectric hysteresis behaviour was studied for all the compositions

  12. Subcoulomb fusion of 16O in odd Sm isotopes

    International Nuclear Information System (INIS)

    Pacheco, A.J.

    1989-01-01

    Cross sections for the formation of evaporation residues were measured for the reaction of 16 O with the odd 147 Sm and 149 Sm nuclei at near barrier energies. The results are well described by statistical model calculations. Fusion cross sections as a function of energy do not show any unusual behaviour that could be attributed to the presence of unpaired nucleons. An analysis based on a one-dimensional penetration model that includes the effect of permanent quadrupolar deformations shows that the extracted values of the parameter β 2 follow the systematics established by the rest of the even samarium isotopes. The dependence of β 2 on the mass of the target nucleus indicates that the influence exerted by collective aspects upon the subbarrier fusion process increases rapidly as a function of the number of neutrons added to the spherical semimagic 144 Sm nucleus. (Author) [es

  13. PVD Ti coatings on Sm-Co magnets

    International Nuclear Information System (INIS)

    Bovda, O.M.; Bovda, V.O.; Garkusha, I.E.; Leonov, S.O.; Onishchenko, L.V.; Tereshin, V.I.; Totrika, O.S.; Chen, C.H.

    2008-01-01

    The combination of conventional ion-plasma deposition (PVD) and pulsed plasma technologies (PPT) has been applied for rare-earth Sm-Co based magnets, to provide them with enhanced corrosion resistance. The influence of pulsed plasma treatment on Sm-Co magnets with deposited titanium PVD coatings has been investigated. It was revealed that thickness of modified layer significantly depends on the thickness of initial titanium film and plasma treatment regimes. As a result of plasma treatment with energy density of 30 J/cm 2 and pulse duration of ∼ 5 μs fine-grained layer with the thickness of 70 microns has been formed on the Sm-Co magnet with pure titanium film of 50 micron. According to SEM analyses considerable diffusion of titanium to the bulk of the magnet, on the depth of 20 microns, took place. Such reaction enhances strong bonding between the coating and the magnet

  14. Study on cellular survival adaptive response induced by low dose irradiation of 153Sm

    International Nuclear Information System (INIS)

    Zhu Shoupeng; Xiao Dong

    1999-01-01

    The present study engages in determining whether low dose irradiation of 153 Sm could cut down the responsiveness of cellular survival to subsequent high dose exposure of 153 Sm so as to make an inquiry into approach the protective action of adaptive response by second irradiation of 153 Sm. Experimental results indicate that for inductive low dose of radionuclide 153 Sm 3.7 kBq/ml irradiated beforehand to cells has obvious resistant effect in succession after high dose irradiation of 153 Sm 3.7 x 10 2 kBq/ml was observed. Cells exposed to low dose irradiation of 153 Sm become adapted and therefore the subsequent cellular survival rate induced by high dose of 153 Sm is sufficiently higher than high dose of 153 Sm merely. It is evident that cellular survival adaptive response could be induced by pure low dose irradiation of 153 Sm only

  15. Phase formation and crystallization behavior of melt spun Sm-Fe-based alloys

    International Nuclear Information System (INIS)

    Shield, J.E.

    1999-01-01

    The phase formation and microstructures of Sm-Fe alloys have been investigated at Sm levels of 11 and 17 atomic percent and with alloying additions of Ti and C. At lower Sm content, virtually phase pure SmFe 7 formed, while higher Sm content resulted in the formation of SmFe 7 , SmFe 2 and amorphous phases. The addition of Ti and C resulted in greater stability and a larger volume fraction of the amorphous phase. The binary Sm-Fe alloys at both Sm levels had tremendously variable microstructures, with large discrepancies in grain size and phase distribution from region to region. The addition of Ti and C tended to result in a more homogeneous microstructure, as well as a refinement in the microstructural scale. (orig.)

  16. Polymorphous GdScO3 as high permittivity dielectric

    International Nuclear Information System (INIS)

    Schäfer, A.; Rahmanizadeh, K.; Bihlmayer, G.; Luysberg, M.; Wendt, F.; Besmehn, A.; Fox, A.

    2015-01-01

    Four different polymorphs of GdScO 3 are assessed theoretically and experimentally with respect to their suitability as a dielectric. The calculations carried out by density functional theory reveal lattice constants, band gaps and the energies of formation of three crystal phases. Experimentally all three crystal phases and the amorphous phase can be realized as thin films by pulsed laser deposition using various growth templates. Their respective crystal structures are confirmed by X-ray diffraction and transmission electron microscopy reflecting the calculated lattice constants. X-ray photoelectron spectroscopy unveils the band gaps of the different polymorphs of GdScO 3 which are above 5 eV for all films demonstrating good insulating properties. From capacitance voltage measurements, high permittivities of up to 27 for hexagonal GdScO 3 are deduced. - Highlights: • Different epitaxial polymorph phases of GdScO 3 were grown by pulsed laser deposition. • The cubic phase of GdScO 3 is reported for the first time. • All phases are proven to be useful for the use in silicon based and III–V based microelectronic devices.

  17. Solution growth of Tb doped Gd_2O_3 film

    International Nuclear Information System (INIS)

    Ghosh, M.; Pitale, S.; Desai, D.G.; Patra, G.D.; Sen, S.; Gadkari, S.C.

    2016-01-01

    Nanomaterials of Gd_2O_3 have proven applications in medical imaging and cancer therapy due to the presence of element Gd. Also Gd_2O_3 films have been grown by vapor phase method as well as self assembly in solution and studied as a high-k dielectric and efficient luminescence material. Here, we report a method to obtain Tb doped Gd_2O_3 film by solution growth method followed by suitable heat treatment. Uniform films of Tb doped Gadolinium hydroxycarbonate have been deposited on fused quartz substrates kept inside a solution containing gadolinium nitrate, terbium nitrate and Urea maintained at 90°C. Gadolinium hydroxy-carbonate films are then treated at 800°C for 2 hour to obtain Tb doped cubic Gd_2O_3 as confirmed by X-ray diffraction measurement. The photoluminescence spectra display characteristic Tb emission at 544 nm when excited at 285 nm. The lifetime of Tb emission is found to be of the order of few microseconds. (author)

  18. Contribution to the qualification of Gd calculation in PWR reactors

    International Nuclear Information System (INIS)

    Chaucheprat, Patrick.

    1982-06-01

    This thesis presents the state of knowledge on gadolinium and the advantages of its use as burnable poison. A study on the behaviour of gadolinium makes it possible to bring out the essential parameters to which it is sensitive. The most important part of this work is devoted to the measurements by oscillations carried out in Minerve in 1981. The conceiving and implementation of this campaign are reported. The experimental results and the amending factors linked to the interpretation are presented. To complete this study at zero time, it seemed useful to process configurations with fuel clusters of UO 2 - Gd 2 O 3 in order to see the effect of UO 2 - Gd 2 O 3 rods in interaction. To this end, efficiency determinations of UO 2 - Gd 2 O 3 rod clusters were carried out in the Melodie lattice. The second part of this work involves the change in the gadolinium. Two main points are tackled here. The first concerns the determinations by oscillations of ''reconstituted'' samples that are composed of two concentric rings with various 235 U enrichments and gadolinium levels so as to simulate irradiated UO 2 - Gd 2 O 3 fuel. The second point is devoted to the description of the GEDEON experiment. UO 2 - Gd 2 O 3 rods will be irradiated in a 13 x 13 lattice of which the spectrum is representative of that of a PWR. This experiment will take place in the centre of the Melusine reactor at Grenoble [fr

  19. Gd-HOPO Based High Relaxivity MRI Contrast Agents

    Energy Technology Data Exchange (ETDEWEB)

    Datta, Ankona; Raymond, Kenneth

    2008-11-06

    Tris-bidentate HOPO-based ligands developed in our laboratory were designed to complement the coordination preferences of Gd{sup 3+}, especially its oxophilicity. The HOPO ligands provide a hexadentate coordination environment for Gd{sup 3+} in which all he donor atoms are oxygen. Because Gd{sup 3+} favors eight or nine coordination, this design provides two to three open sites for inner-sphere water molecules. These water molecules rapidly exchange with bulk solution, hence affecting the relaxation rates of bulk water olecules. The parameters affecting the efficiency of these contrast agents have been tuned to improve contrast while still maintaining a high thermodynamic stability for Gd{sup 3+} binding. The Gd- HOPO-based contrast agents surpass current commercially available agents ecause of a higher number of inner-sphere water molecules, rapid exchange of inner-sphere water molecules via an associative mechanism, and a long electronic relaxation time. The contrast enhancement provided by these agents is at least twice that of commercial contrast gents, which are based on polyaminocarboxylate ligands.

  20. Large magnetocaloric effect of GdNiAl2 compound

    International Nuclear Information System (INIS)

    Dembele, S.N.; Ma, Z.; Shang, Y.F.; Fu, H.; Balfour, E.A.; Hadimani, R.L.; Jiles, D.C.; Teng, B.H.; Luo, Y.

    2015-01-01

    This paper presents the structure, magnetic properties, and magnetocaloric effect of the polycrystalline compound GdNiAl 2 . Powder X-ray diffraction (XRD) measurement and Rietveld refinement revealed that GdNiAl 2 alloy is CuMgAl 2 -type phase structure with about 1 wt% GdNi 2 Al 3 secondary phase. Magnetic measurements suggest that the compound is ferromagnetic and undergoes a second-order phase transition near 28 K. The maximum value of magnetic entropy change reaches 16.0 J/kg K for an applied magnetic field change of 0–50 kOe and the relative cooling power was 6.4×10 2 J/kg. It is a promising candidate as a magnetocaloric material working near liquid hydrogen temperature (~20 K) exhibiting large relative cooling power. - Highlights: • Preferred orientation with axis of [010] was found in the GdNiAl 2 compound. • The ΔS Mmax and the RCP are 16.0 J/kg K and 640 J/kg, respectively, for ΔH=50 kOe. • Relative low rare earth content in GdNiAl 2 comparing with other candidates

  1. Lifetime measurements of the excited states in {sup 145} Sm

    Energy Technology Data Exchange (ETDEWEB)

    El-Badry, A M; Abdel Samie, Sh; Ahmad, A A [Depatment of Physics, Faculty of Science, ElMinia University, ElMinia, (Egypt); Kuroyanagi, T; Odahara, A; Gono, Y; Morinobu, S [Tandem Accelerator Laboratory, Department of Physics, Kyushu University, (Japan)

    1997-12-31

    Lifetime of the excited levels in {sup 145} Sm has been measured through the {sup 139} La ({sup 10} B, 4 n){sup 145} Sm nuclear reaction. The optimal beam energy of 49 MeV was determined from the measurements of the excitation function and Cascade program. With the possibility of studying lifetime of this nucleus a conventional plunger system have been designed and constructed at kyushu University tandem accelerator laboratory. A La target of 0.22 mg/cm{sup 2} thickness which was evaporated onto a Au foil of 2 mg/cm{sup 2} thickness was used. Since the recoil velocity was estimated to be 1.76 mm/ns (beta 0.00585), the measurable time range resulted in the range from 5 Ps to 5 ns. The single spectra measurements were performed at the 20 plunger positions in the range from 10 {mu} to 10 mm. Analyses of the data were carried using hypermet and/or GF2 program to obtain the lifetimes. A new list of lifetimes for 12 excited states up to 3.922 MeV excitations for {sup 145} Sm were determined for the first time. Decay curves of the these transitions are discussed. The new lifetimes of excited states in {sup 145} Sm enabled us to understand the electromagnetic properties. The deduced transition probabilities were established and compared with that of N = 83 isotones and the closed shell nucleus {sup 144} Sm. In addition, a nuclear structure of {sup 145} Sm have been discussed and proposed in framework of the shell model. 4 figs., 1 tab.

  2. Electrodeposition of Al-Ta alloys in NaCl-KCl-AlCl{sub 3} molten salt containing TaCl{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Kazuki; Matsushima, Hisayoshi; Ueda, Mikito, E-mail: mikito@eng.hokudai.ac.jp

    2016-12-01

    Highlights: • Electrodeposition of Al-Ta alloys in an AlCl{sub 3}-NaCl-KCl-TaCl{sub 5} melt was carried out. • We were obtained 72 at% Ta-Al alloy at 0.3 V. • Amorphous Ta-Al was formed in high Ta concentration. - Abstract: To form Al-Ta alloys for high temperature oxidation resistance components, molten salt electrolysis was carried out in an AlCl{sub 3}-NaCl-KCl melt containing TaCl{sub 5} at 423 K. The voltammogram showed two cathodic waves at 0.45 V and 0.7 V vs. Al/Al(III), which may correspond to reduction from Ta(V) to Ta(III) and from Ta(III) to tantalum metal, respectively. Electrodeposits of Al and Ta were obtained in the range from −0.05 to 0.3 V and the highest concentration of Ta in the electrodeposit was 72 at% at 0.3 V. With increasing Ta content in the alloy, the morphology of the electrodeposits became powdery and the particle size smaller.

  3. Combined experimental and theoretical assessments of the lattice dynamics and optoelectronics of TaON and Ta3N5

    KAUST Repository

    Nurlaela, Ela; Harb, Moussab; Del Gobbo, Silvano; Vashishta, Manish; Takanabe, Kazuhiro

    2015-01-01

    Presented herein is a detailed discussion of the properties of the lattice dynamic and optoelectronic properties of tantalum(V) oxynitride (TaON) and tantalum(V) nitride (Ta3N5), from experimental and theoretical standpoint. The active Raman and infra red (IR) frequencies of TaON and Ta3N5 were measured using confocal Raman and Fourier Transform Infrared spectroscopies (FTIR) and calculated using the linear response method within the density functional perturbation theory (DFPT). The detailed study leads to an exhaustive description of the spectra, including the symmetry of the vibrational modes. Electronic structures of these materials were computed using DFT within the range-separated hybrid HSE06 exchange–correlation formalism. Electronic and ionic contributions to the dielectric constant tensors of these materials were obtained from DFPT within the linear response method using the PBE functional. Furthermore, effective mass of photogenerated holes and electrons at the band edges of these compounds were computed from the electronic band structure obtained at the DFT/HSE06 level of theory. The results suggest that anisotropic nature in TaON and Ta3N5 is present in terms of dielectric constant and effective masses.

  4. Ta penetration into template-type porous low-k material during atomic layer deposition of TaN

    International Nuclear Information System (INIS)

    Furuya, Akira; Ohtsuka, Nobuyuki; Misawa, Kaori; Shimada, Miyoko; Ogawa, Shinichi

    2005-01-01

    Ta penetration into a planar template-type porous low-k film during atomic layer deposition of TaN has been investigated by evaluating relations between Ta penetration and number of deposition cycles, exposure time of Ta precursor per deposition cycle, substrate temperature, and porosity of the porous low-k. The precursors were pentakisdimethylaminotantalum [PDMAT:Ta(N(CH 3 ) 2 ) 5 ] and NH 3 . The porous low-k was a methylsiloxane (MSX) whose pore size in the maximum distribution and porosity of the porous low-k were 0-1.9 nm and 0%-47%. Depth profile of the Ta penetration was measured by transmission electron microscopy and energy dispersive x-ray spectroscopy. The amount of penetrated and the penetration depth depended on the porosity. It was found that the precursors penetrate into the MSX film dominantly by gas phase diffusion through pores connecting from the surface to the inside. Increased surface area of the MSX film due to the pores results in a depletion of precursor at the wafer edge, and that this depletion causes the penetration characteristics at the edge of wafer differ from those at the center of the wafer. Moreover, the thickness required for the pore sealing by additive liner deposition is discussed

  5. Modelling the mechanical behaviour of heterogeneous Ta/TA6V welded joints: behaviour and failure criteria

    International Nuclear Information System (INIS)

    Paris, Th.

    2008-12-01

    As laser welding of two different materials (heterogeneous welding) leads to a joint having a characteristic size close to the millimetre, i.e. much smaller than that of a structure, and as such a junction displays completely different mechanical properties because of the metallurgical transformations induced by intense thermal loading, the aim of this research thesis is to develop a behaviour model, flexible and robust enough, to represent all together the mechanical behaviours of the Ta, the TA6V and the melted zone. This model must be able to take plasticity and visco-plasticity into account, and also to provide a failure criterion through damage mechanics and its coupling with the behaviour. The author first reports the experimental characterization of the base materials (Ta and TA6V) by using tensile tests under different strain rates and different directions, relaxation tests and fatigue shear tests. He also characterizes the melted zone by describing the influence of a thermal treatment (induced by welding) on the formation of the melted zone, and by using different tests: four point bending on notched specimens, nano-indentation test, and longitudinal tensile test. In a second part, the author develops the model within the framework of continuum thermodynamics, and explores the numerical issues. The last part deals with the validation of the model for the concerned materials (Ta and TA6V) and melted zone

  6. Combined experimental and theoretical assessments of the lattice dynamics and optoelectronics of TaON and Ta3N5

    KAUST Repository

    Nurlaela, Ela

    2015-06-15

    Presented herein is a detailed discussion of the properties of the lattice dynamic and optoelectronic properties of tantalum(V) oxynitride (TaON) and tantalum(V) nitride (Ta3N5), from experimental and theoretical standpoint. The active Raman and infra red (IR) frequencies of TaON and Ta3N5 were measured using confocal Raman and Fourier Transform Infrared spectroscopies (FTIR) and calculated using the linear response method within the density functional perturbation theory (DFPT). The detailed study leads to an exhaustive description of the spectra, including the symmetry of the vibrational modes. Electronic structures of these materials were computed using DFT within the range-separated hybrid HSE06 exchange–correlation formalism. Electronic and ionic contributions to the dielectric constant tensors of these materials were obtained from DFPT within the linear response method using the PBE functional. Furthermore, effective mass of photogenerated holes and electrons at the band edges of these compounds were computed from the electronic band structure obtained at the DFT/HSE06 level of theory. The results suggest that anisotropic nature in TaON and Ta3N5 is present in terms of dielectric constant and effective masses.

  7. Hydrogen stability of SmCo5 permanent magnet

    International Nuclear Information System (INIS)

    Lukin, A.; Rabinovich, Y.; Bala, H.

    2001-01-01

    The present work has been performed with purpose to determine the level of hydrogen stability of sintered SmCo 5 permanent magnets by means of accelerated tests, to study the effect of hydrogen on the magnetic and mechanical properties of the permanent magnets and to establish the criteria of hydrogenation level and the activation energy of this process. In addition, the effect of hydrogen on the properties of sintered SmCo 5 permanent magnets in specific conditions of exploitation and storage durability of instruments was studied

  8. The neutron EDM in the SM: a review

    International Nuclear Information System (INIS)

    Dar, Shahida

    2000-08-01

    We review the status of the electric dipole moment (EDM) of neutron in the Standard Model (SM). The contributions of the strong and electroweak interactions are discussed separately. In each case the structure of Lagrangian and the sources of CP violation are specified, and subsequently calculational details are given. These two contributions to the neutron EDM exist in any extension of the SM including supersymmetry, two-doublet models as well as models with more than three generations of fermions. We briefly discuss the status of the neutron EDM in such extensions and give the relevant literature. (author)

  9. Petri nets SM-cover-based on heuristic coloring algorithm

    Science.gov (United States)

    Tkacz, Jacek; Doligalski, Michał

    2015-09-01

    In the paper, coloring heuristic algorithm of interpreted Petri nets is presented. Coloring is used to determine the State Machines (SM) subnets. The present algorithm reduces the Petri net in order to reduce the computational complexity and finds one of its possible State Machines cover. The proposed algorithm uses elements of interpretation of Petri nets. The obtained result may not be the best, but it is sufficient for use in rapid prototyping of logic controllers. Found SM-cover will be also used in the development of algorithms for decomposition, and modular synthesis and implementation of parallel logic controllers. Correctness developed heuristic algorithm was verified using Gentzen formal reasoning system.

  10. First measurement of 153Sm in the SIR

    International Nuclear Information System (INIS)

    Michotte, C.; Ratel, G.; Lucas, L.

    1999-01-01

    In June 1998, the NIST sent to the International Reference System (SIR) a solution of 153 Sm standardized in a 4π ionization chamber. As this radionuclide had not previously been measured in the SIR, the resulting equivalent activity A e,NIST is compared with the value calculated from the efficiency curve of the SIR. However, problems occurred owing to the presence of 154 Eu and 156 Eu impurities in the solution. The manner in which the final equivalent activity value for this solution of 153 Sm has been deduced is described in this report. (authors)

  11. Electron back scattered diffraction study of SmCo magnets

    International Nuclear Information System (INIS)

    Yonamine, T.; Fukuhara, M.; Machado, R.; Missell, F.P.

    2008-01-01

    The remanence and energy product of permanent magnets is a strong function of their crystallographic texture. Electron back scattered diffraction (EBSD) is a tool for texture analysis providing information about the atomic layers up to 50 nm below the surface of the material. This paper discusses experimental requirements for performing EBSD measurements on rare-earth permanent magnets and presents results on commercial SmCo magnet material. EBSD measurements proved to be very sensitive to misaligned grains and were sensitive to texture in good agreement with information provided by X-ray diffraction scans. Results for nanostructured Sm(CoFeCuZr) z magnets are also discussed

  12. Meltability in system of K2TaF7-NaF-NaCl-KCl

    International Nuclear Information System (INIS)

    Kartsev, V.E.; Kovalev, F.V.; Korshunov, B.G.

    1975-01-01

    Thermographic and visual-polythermal techniques were used to study the meltability in K 2 TaF 7 -NaF-NaCl-KCl system. The tetrahedron-forming sections NaF-NaCl-K 2 TaF 7 xKCl and NaF-K 2 TaF 7 xKCl-2K 2 TaF 7 xNaCl divide the concentration tetrahedron into three particular tetrahedra: NaF-K 2 TaF 7 xKCl-2K 2 TaF 7 xNaCl-K 2 TaF 7 , NaF-NaCl-K 2 TaF 7 xKCl-2K 2 TaF 7 xaCl, and NaF-NaCl-KCl-K 2 TaF 7 xKCl. Non-variant equilibrium points in all of the particular four-component systems have been determined

  13. Electrochemical preparation of Al–Sm intermetallic compound whisker in LiCl–KCl Eutectic Melts

    International Nuclear Information System (INIS)

    Ji, De−Bin; Yan, Yong−De; Zhang, Mi−Lin; Li, Xing; Jing, Xiao−Yan; Han, Wei; Xue, Yun; Zhang, Zhi−Jian; Hartmann, Thomas

    2015-01-01

    Highlights: • The reduction process of Sm(III) was investigated in LiCl–KCl melt on an aluminum electrode at 773 K. • Al–Sm alloy with different phase structure (Al 2 Sm and Al 3 Sm) was prepared by potentiostatic electrolysis on an aluminum electrode with the change of electrolytic potentials and time in LiCl–KCl–SmCl 3 melts. • Al − Sm alloy containing whiskers (Al 4 Sm) was obtained by potentiostatic electrolysis (−2.10 V) on an aluminum electrode for 7 hours with the change of electrolytic temperature and cooling rate in LiCl–KCl–SmCl 3 (16.5 wt. %) melts. The results from micro–hardness test and potentiodynamic polarization test show the micro hardness and corrosion property are remarkably improved with the help of Al–Sm intermetallic compound whiskers. - Abstract: This work presents the electrochemical study of Sm(III) on an aluminum electrode in LiCl–KCl melts at 773 K by different electrochemical methods. Three electrochemical signals in cyclic voltammetry, square wave voltammetry, open circuit chronopotentiometry, and cathode polarization curve are attributed to different kinds of Al–Sm intermetallic compounds, Al 2 Sm, Al 3 Sm, and Al 4 Sm, respectively. Al–Sm alloy with different phase structure (Al 2 Sm and Al 3 Sm) could be obtained by the potentiostatic electrolysis with the change of electrolytic potentials and time. Al–Sm alloy containing whiskers (Al 4 Sm) was obtained by potentiostatic electrolysis (−2.10 V) on an aluminum electrode for 7 hours with the change of electrolytic temperature and cooling rate in LiCl–KCl–SmCl 3 (16.5 wt. %) melts. The XRD and SEM&EDS were employed to investigate the phase composition and microstructure of Al–Sm alloy. SEM analysis shows that lots of needle−like precipitates formed in Al–Sm alloy, and their ratios of length to diameter are found to be greater than 10 to 1. The TEM and electron diffraction pattern were performed to investigate the crystal structure of the

  14. Antiferromagnetic ordering in GdRhIn{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Latka, K.; Rams, M. [Marian Smoluchowski Inst. of Physics, Jagiellonian Univ., Krakow (Poland); Kmiec, R.; Pacyna, A.W. [Henryk Niewodniczanski Inst. of Nuclear Physics, Polish Academy of Sciences, Krakow (Poland); Zaremba, V.I. [Inorganic Chemistry Dept., Ivan Franko National Univ. of Lviv, Lviv (Ukraine); Inst. fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Univ. Muenster (Germany); Poettgen, R. [Inst. fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Univ. Muenster (Germany)

    2004-09-01

    A polycrystalline sample of tetragonal GdRhIn{sub 5} (HoCoGa{sub 5} type, space group P4/mmm) was obtained by induction melting of the elements in a glassy carbon crucible in a water-cooled sample chamber and subsequent annealing at 670 K. X-ray powder data yielded the cell parameters a = 460.65(7), c = 743.52(12) pm. The magnetic and electronic properties of GdRhIn{sub 5} have been studied by magnetic susceptibility, electrical resistivity, and {sup 155}Gd Moessbauer spectroscopic measurements. Antiferromagnetic ordering is detected at 41.0(2) K. The results are discussed using a simple molecular field approximation. (orig.)

  15. Canted magnetic moments at the Gd(0001) surface

    International Nuclear Information System (INIS)

    Li Donggi; Zhang Jiandi; Dowben, P.A.; Tang, H.; Walker, T.G.; Hopster, H.

    1993-01-01

    With spin polarized electron spectroscopies, the authors have investigated ordered Gd(0001) films deposited on W(110). The photoemission features of the gadolinium 5d surface state, the 4f levels, and the background exhibit considerable spin polarization along the same direction in the plane of the film, indicative of ferromagnetic coupling between the surface and the bulk. The 4f spin polarized photoemission data provides strong evidence that the surface 4f polarization differs from the bulk 4f polarization for Gd(0001). The temperature dependent measurements with spin polarized secondary electron spectroscopy conclusively establishes that the surface of clean Gd(0001) possesses a perpendicular polarization component which persists to an enhanced surface Curie temperature. Small amounts of contamination at the surface result in the disappearance of the perpendicular component and, therefore, a more perfect ferromagnetic coupling between the surface and the bulk

  16. Magnetic transition in Co/(Gd-Co) multilayers

    International Nuclear Information System (INIS)

    Svalov, A.V.; Fernandez, A.; Barandiaran, J.M.; Vas'kovskiy, V.O.; Orue, I.; Tejedor, M.; Kurlyandskaya, G.V.

    2008-01-01

    [Co/Gd 0.36 Co 0.64 ] 4 /Co multilayers with Co termination layer have been prepared by rf sputtering. They form macroscopic ferrimagnets with a compensation temperature (T comp ) determined by the thickness ratio of the layers. In low fields the magnetization of Co and Gd-Co layers are along the axis of the applied field. Increasing field makes the moments of both the Co and Gd-Co layers deviate from the axis of the field giving rise to a transition into a twisted state. These magnetic transitions were studied by vibrating sample magnetometer (VSM), magneto-optic Kerr effect and magnetoresistance measurements at various temperatures. The nucleation and evolution of surface- and bulk-twisted magnetic states were also observed in these multilayers

  17. MR lymphography with macromolecular Gd-DTPA compounds

    International Nuclear Information System (INIS)

    Hamm, B.; Wagner, S.; Branding, G.; Taupitz, M.; Wolf, K.J.

    1990-01-01

    This paper investigates the suitability of macromolecular Gd-DTPA compounds as signal-enhancing lymphographic agents in MR imaging. Two Gd-DTPA polylysin compounds and Gd-DTPA albumin, with molecular weights of 48,000,170,000, and 87,000 daltons, respectively, were tested in rabbits at gadolinium doses of 5 and 15 μmol per animal. Three animals were examined at each dose with T1-weighted sequences. The iliac lymph nodes were imaged prior to and during unilateral endolymphatic infusion into a femoral lymph vessel as well as over a period of 2 hours thereafter. All contrast media showed a homogeneous and pronounced signal enhancement in the lymph nodes during infusion at both doses

  18. Gd-DTPA administered MR imaging of intracranial mass lesions

    International Nuclear Information System (INIS)

    Mihara, Futoshi; Hirakata, Ryosuke; Hasuo, Kanehiro; Yasumori, Kotaro; Yoshida, Kisaku; Kuroiwa, Toshiro; Masuda, Kouji; Fukui, Masashi

    1989-01-01

    Magnetic resonance (MR) images of 13 intracranial mass lesions taken with the intravenous administration of gadolinium-DTPA were evaluated in comparison with precontrast computed tomography (CT), postcontrast CT, and precontrast MR. In the MR images taken with Gd-DTPA, tumor delineation improved in eight of 13 cases (62%) in comparison with precontrast MR images, and in seven of 13 cases (54%) in comparison with the overall evaluation of precontrast CT, postcontrast CT, and precontrast MR images. Tumor demarcation was unchanged in the remaining cases; no deterioration was observed with Gd-DTPA administration. MR imaging with Gd-DTPA should be performed to better evaluate the extent of intracranial mass lesions and to provide additional information. (author)

  19. Effect of Gd substitution on structure and spectroscopic properties of (Lu,Gd)2O3:Eu ceramic scintillator

    Science.gov (United States)

    Cao, Maoqing; Hu, Zewang; Ivanov, Maxim; Dai, Jiawei; Li, Chaoyu; Kou, Huamin; Shi, Yun; Chen, Haohong; Xu, Jiayue; Pan, Yubai; Li, Jiang

    2018-02-01

    In this paper, (Lu1-xGdx)2O3:Eu (x = 0, 0.1, 0.3, 0.5, 0.7, 0.9) ceramics were consolidated by the solid-state reaction method combined with vacuum sintering without sintering aids. We investigated the effect of the varying contents of Gd2O3 on the structure and spectroscopic properties of (Lu1-xGdx)2O3:Eu ceramics. X-ray diffraction (XRD) patterns indicate that proper amount of Gd2O3 can incorporate well with Lu2O3 and form Lu2O3-Gd2O3 solid solution. However, excessive Gd3+-doping in Lu2O3 will lead to the cubic phase transforming into monoclinic even hexagonal phase. The Gd3+ substitution no more than 50% of Lu2O3 enhances the radioluminescence, and reduces the fluorescence lifetime. Transmittance, photoluminescence, and radiation damage of the (Lu1-xGdx)2O3:Eu scintillation ceramics were also studied.

  20. Enhanced post-annealing stability of perpendicular Ta/CoFeB/Mg/MgO multilayers by inhibiting Ta diffusion

    International Nuclear Information System (INIS)

    Li, Xu-Jing; Jiang, Shao-Long; Zhang, Jing-Yan; Liu, Qian-Qian; Liu, Yi-Wei; Zhao, Jian-Cheng; Wu, Zheng-Long; Feng, Chun; Li, Ming-Hua; Yu, Guang-Hua

    2016-01-01

    Graphical abstract: To reveal the underlying mechanism of Mg influence on the enhanced post-annealing stability of perpendicular Ta/CoFeB/Mg/MgO multilayers, the X-ray photoelectron spectroscopy analysis have been performed. It is found that a certain amount of Mg interlayer at the CoFeB/MgO interface could prevent the Ta oxidation to some extent due to the oxygen deficit MgO_x (x < 1), and consequently lower the diffusion motivation of Ta from the bottom layer to the CoFeB/MgO interfaces to some extent during the annealing process. The prevention of Ta diffusion realizes the effective hybridization of Fe and O at the CoFeB/MgO interface and maintains interfacial magnetic anisotropy (K_C_o_F_e_B_/_M_g_O). As a result, the perpendicular magnetic anisotropy at high annealing temperatures was maintained. - Highlights: • High annealing stability of perpendicular Ta/CoFeB/Mg/MgO multilayers was realized. • X-ray photoelectron spectroscopy analysis has been performed to explore the reasons. • The prevention of Ta diffusion was realized by introducing Mg at the CoFeB/MgO interface. - Abstracts: To reveal the underlying mechanism of Mg influence on the enhanced post-annealing stability of perpendicular Ta/CoFeB/Mg/MgO multilayers, the X-ray photoelectron spectroscopy analysis has been performed. It is found that a certain amount of Mg interlayer at the CoFeB/MgO interface could prevent the Ta oxidation, and consequently lower the diffusion motivation of Ta from the bottom layer to the CoFeB/MgO interfaces to some extent in the annealing process. The prevention of Ta diffusion realizes the effective hybridization of Fe and O at the CoFeB/MgO interface and maintains interfacial magnetic anisotropy (KCoFeB/MgO). As a result, the perpendicular magnetic anisotropy at high annealing temperatures is maintained

  1. Enhanced post-annealing stability of perpendicular Ta/CoFeB/Mg/MgO multilayers by inhibiting Ta diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xu-Jing; Jiang, Shao-Long; Zhang, Jing-Yan; Liu, Qian-Qian; Liu, Yi-Wei; Zhao, Jian-Cheng [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China); Wu, Zheng-Long [Analytical and Testing Center, Beijing Normal University, Beijing 100875 (China); Feng, Chun, E-mail: fengchun@ustb.edu.cn [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China); Li, Ming-Hua [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China); Yu, Guang-Hua, E-mail: ghyu@mater.ustb.edu.cn [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China)

    2016-03-01

    Graphical abstract: To reveal the underlying mechanism of Mg influence on the enhanced post-annealing stability of perpendicular Ta/CoFeB/Mg/MgO multilayers, the X-ray photoelectron spectroscopy analysis have been performed. It is found that a certain amount of Mg interlayer at the CoFeB/MgO interface could prevent the Ta oxidation to some extent due to the oxygen deficit MgO{sub x} (x < 1), and consequently lower the diffusion motivation of Ta from the bottom layer to the CoFeB/MgO interfaces to some extent during the annealing process. The prevention of Ta diffusion realizes the effective hybridization of Fe and O at the CoFeB/MgO interface and maintains interfacial magnetic anisotropy (K{sub CoFeB/MgO}). As a result, the perpendicular magnetic anisotropy at high annealing temperatures was maintained. - Highlights: • High annealing stability of perpendicular Ta/CoFeB/Mg/MgO multilayers was realized. • X-ray photoelectron spectroscopy analysis has been performed to explore the reasons. • The prevention of Ta diffusion was realized by introducing Mg at the CoFeB/MgO interface. - Abstracts: To reveal the underlying mechanism of Mg influence on the enhanced post-annealing stability of perpendicular Ta/CoFeB/Mg/MgO multilayers, the X-ray photoelectron spectroscopy analysis has been performed. It is found that a certain amount of Mg interlayer at the CoFeB/MgO interface could prevent the Ta oxidation, and consequently lower the diffusion motivation of Ta from the bottom layer to the CoFeB/MgO interfaces to some extent in the annealing process. The prevention of Ta diffusion realizes the effective hybridization of Fe and O at the CoFeB/MgO interface and maintains interfacial magnetic anisotropy (KCoFeB/MgO). As a result, the perpendicular magnetic anisotropy at high annealing temperatures is maintained.

  2. Behavior of Gd-DTPA in simulated bank filtration

    International Nuclear Information System (INIS)

    Moeller, Peter; Knappe, Andrea; Dulski, Peter; Pekdeger, Asaf

    2011-01-01

    Research highlights: → Gd-DTPA and similar products are common pollutants in surface and groundwater and prove to be a reliable monitor for mixing of groundwater with surface water loaded with effluents from sewage treatment plants. → Within a 30 m column filled with Pleistocene sand Gd-DTPA is reduced by 16% only within one month time by transmetallation. → Artificial bank filtration is not very effective in reducing Gd-DTPA in infiltrating water. - Abstract: The behavior of Gd-DTPA during bank filtration was simulated in a 30 m column filled with Pleistocene sand and flushed by surface water from a lakeside in Berlin, Germany. The surface water is about a 1:1 mixture of river water and effluents from a sewage treatment plant. Throughout 34 days this water was continuously spiked with Gd-DTPA at a level of 60 μg/L. The broad plateau of the Gd-DTPA pulse declined by 15.4% within 34 days by transmetallation. Nine percentage of the total decline is caused by Y and rare earth elements; the remaining part is attributed to Cu 2+ which is the most influential metal in surface water. All other metals also contributing to transmetallation are combined with Cu to Cu equivalents because only the rate constant of transmetallation of Cu 2+ is known. The analytical results of the column effluents prove the pseudo-first-order kinetics of transmetallation based on reversible sorption of metals by pools in the column sediment and disprove biodegradation at noticeable levels. The mass ratio of water to tracer is 10 .

  3. Behavior of Gd-DTPA in simulated bank filtration

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, Peter, E-mail: pemoe@gfz-potsdam.de [Freie Universitaet Berlin, Malteserstr. 74-100, AB Hydrogeologie, 12249 Berlin (Germany)] [Helmholtz Zentrum Potsdam, Deutsches GeoForschungsZentrum, Telegrafenberg, 14473 Potsdam (Germany); Knappe, Andrea [Freie Universitaet Berlin, Malteserstr. 74-100, AB Hydrogeologie, 12249 Berlin (Germany); Dulski, Peter [Helmholtz Zentrum Potsdam, Deutsches GeoForschungsZentrum, Telegrafenberg, 14473 Potsdam (Germany); Pekdeger, Asaf [Freie Universitaet Berlin, Malteserstr. 74-100, AB Hydrogeologie, 12249 Berlin (Germany)

    2011-01-15

    Research highlights: {yields} Gd-DTPA and similar products are common pollutants in surface and groundwater and prove to be a reliable monitor for mixing of groundwater with surface water loaded with effluents from sewage treatment plants. {yields} Within a 30 m column filled with Pleistocene sand Gd-DTPA is reduced by 16% only within one month time by transmetallation. {yields} Artificial bank filtration is not very effective in reducing Gd-DTPA in infiltrating water. - Abstract: The behavior of Gd-DTPA during bank filtration was simulated in a 30 m column filled with Pleistocene sand and flushed by surface water from a lakeside in Berlin, Germany. The surface water is about a 1:1 mixture of river water and effluents from a sewage treatment plant. Throughout 34 days this water was continuously spiked with Gd-DTPA at a level of 60 {mu}g/L. The broad plateau of the Gd-DTPA pulse declined by 15.4% within 34 days by transmetallation. Nine percentage of the total decline is caused by Y and rare earth elements; the remaining part is attributed to Cu{sup 2+} which is the most influential metal in surface water. All other metals also contributing to transmetallation are combined with Cu to Cu equivalents because only the rate constant of transmetallation of Cu{sup 2+} is known. The analytical results of the column effluents prove the pseudo-first-order kinetics of transmetallation based on reversible sorption of metals by pools in the column sediment and disprove biodegradation at noticeable levels. The mass ratio of water to tracer is <10{sup 10}.

  4. The isothermal section at 500 deg. C of the Gd-Tb-Ga ternary system

    International Nuclear Information System (INIS)

    Li, J.Q.; Jian, Y.X.; Ao, W.Q.; Zhuang, Y.H.; He, W.

    2006-01-01

    Phase equilibria in the Gd-Tb-Ga ternary system at 500 deg. C were investigated by X-ray powder diffraction and differential scanning calorimetry. The binary compounds, Gd 5 Ga 3 , Gd 3 Ga 2 , GdGa, GdGa 2 , Tb 5 Ga 3 , TbGa, TbGa 2 and TbGa 3 have been confirmed at 500 deg. C. No ternary compound was found in this system. The isothermal section of this system at 500 deg. C was constructed. It is composed of 7 single-phase regions, 8 two-phase regions and 2 three-phase regions. Four ternary continuous solid solutions (Gd, Tb), (Gd, Tb) 5 Ga 3 , (Gd, Tb)Ga, (Gd, Tb)Ga 2 were formed in this isothermal section. The maximum solid solubilities of Ga in (Gd, Tb) at 500 deg. C is 5.0 at.%. The homogeneity range of (Gd, Tb)Ga 2 is from 20 to 33.3 at.% Ga in Gd-Ga side but limited in Tb-Ga side. The solid solubilities of Ga in the other phases cannot be detected. The Curie temperatures of the Gd 0.6 Tb 0.4-x Ga x alloys increase from 270 to 298 K as x increases from 0 to 0.03

  5. Novel Gd nanoparticles enhance vascular contrast for high-resolution magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Tot Bui

    2010-09-01

    Full Text Available Gadolinium (Gd, with its 7 unpaired electrons in 4f orbitals that provide a very large magnetic moment, is proven to be among the best agents for contrast enhanced MRI. Unfortunately, the most potent MR contrast agent based on Gd requires relatively high doses of Gd. The Gd-chelated to diethylene-triamine-penta-acetic acid (DTPA, or other derivatives (at 0.1 mmole/kg recommended dose, distribute broadly into tissues and clear through the kidney. These contrast agents carry the risk of Nephrogenic Systemic Fibrosis (NSF, particularly in kidney impaired subjects. Thus, Gd contrast agents that produce higher resolution images using a much lower Gd dose could address both imaging sensitivity and Gd safety.To determine whether a biocompatible lipid nanoparticle with surface bound Gd can improve MRI contrast sensitivity, we constructed Gd-lipid nanoparticles (Gd-LNP containing lipid bound DTPA and Gd. The Gd-LNP were intravenously administered to rats and MR images collected. We found that Gd in Gd-LNP produced a greater than 33-fold higher longitudinal (T(1 relaxivity, r(1, constant than the current FDA approved Gd-chelated contrast agents. Intravenous administration of these Gd-LNP at only 3% of the recommended clinical Gd dose produced MRI signal-to-noise ratios of greater than 300 in all vasculatures. Unlike current Gd contrast agents, these Gd-LNP stably retained Gd in normal vasculature, and are eliminated predominately through the biliary, instead of the renal system. Gd-LNP did not appear to accumulate in the liver or kidney, and was eliminated completely within 24 hrs.The novel Gd-nanoparticles provide high quality contrast enhanced vascular MRI at 97% reduced dose of Gd and do not rely on renal clearance. This new agent is likely to be suitable for patients exhibiting varying degrees of renal impairment. The simple and adaptive nanoparticle design could accommodate ligand or receptor coating for drug delivery optimization and in vivo drug

  6. Gadolinium scandium germanide, Gd2Sc3Ge4

    Directory of Open Access Journals (Sweden)

    Sumohan Misra

    2009-04-01

    Full Text Available Gd2Sc3Ge4 adopts the orthorhombic Pu5Rh4-type structure. The crystal structure contains six sites in the asymmetric unit: two sites are statistically occupied by rare-earth atoms with Gd:Sc ratios of 0.967 (4:0.033 (4 and 0.031 (3:0.969 (3, one site (.m. symmetry is occupied by Sc atoms, and three distinct sites (two of which with .m. symmetry are occupied by Ge atoms. The rare-earth atoms form two-dimensional slabs with Ge atoms occupying the trigonal-prismatic voids.

  7. 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.

  8. Lithiotantite, ideally LiTa3O8

    Directory of Open Access Journals (Sweden)

    Aba C. Persiano

    2012-05-01

    Full Text Available Lithiotantite (lithium tritantalum octaoxide and lithiowodginite are natural dimorphs of LiTa3O8, corresponding to the laboratory-synthesized L-LiTa3O8 (low-temperature form and M-LiTa3O8 (intermediate-temperature form phases, respectively. Based on single-crystal X-ray diffraction data, this study presents the first structure determination of lithiotantite from a new locality, the Murundu mine, Jenipapo District, Itinga, Minas Gerais, Brazil. Lithiotantite is isotypic with LiNb3O8 and its structure is composed of a slightly distorted hexagonal close-packed array of O atoms stacked in the [-101] direction, with the metal atoms occupying half of the octahedral sites. There are four symmetrically non-equivalent cation sites, with three of them occupied mainly by (Ta5+ + Nb5+ and one by Li+. The four distinct octahedra share edges, forming two types of zigzag chains (A and B extending along the b axis. The A chains are built exclusively of (Ta,NbO6 octahedra (M1 and M2, whereas the B chains consist of alternating (Ta,NbO6 and LiO6 octahedra (M3 and M4, respectively. The average M1—O, M2—O, M3—O and M4—O bond lengths are 2.011, 2.004, 1.984, and 2.188 Å, respectively. Among the four octahedra, M3 is the least distorted and M4 the most. The refined Ta contents at the M1, M2 and M3 sites are 0.641 (2, 0.665 (2, and 0.874 (2, respectively, indicating a strong preference of Ta5+ for M3 in the B chain. The refined composition of the crystal investigated is Li0.96Mn0.03Na0.01Nb0.82Ta2.18O8.

  9. Laminated structure in internally oxidized Ru-Ta coatings

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yung-I, E-mail: yichen@mail.ntou.edu.tw

    2012-12-01

    During the development of refractory alloy coatings for protective purposes at high temperature under oxygen-containing atmospheres, previous studies noted and examined the internal oxidation phenomenon for Mo-Ru and Ru-Ta coatings. The internally oxidized zone shows a laminated structure, consisting of alternating oxygen-rich and deficient layers stacked with a general orientation. Previous studies proposed a forming mechanism. To investigate in detail, Ru-Ta coatings were prepared with various rotating speeds of a substrate-holder. The coatings were annealed at 600 Degree-Sign C in an atmosphere continuously purged with 1% O{sub 2}-99% Ar mixed gas for 30 min. Transmission electron microscopy was used to examine the laminated-layer periods. Auger electron spectroscopy depth profiles certified the periodical variation of the related constituents. X-ray photoelectron spectroscopy proved the valence variation of Ta in the near surface, accompanied by the introduction of oxygen ions. The inward diffusion of oxygen was dominated by lattice diffusion. - Highlights: Black-Right-Pointing-Pointer Laminated Ru-Ta coatings consisted of a cyclical gradient concentration. Black-Right-Pointing-Pointer The as-deposited coatings showed a laminated structure with a period of 4-34 nm. Black-Right-Pointing-Pointer Internal oxidation of Ru-Ta coatings executed after annealing in 1% O{sub 2}-Ar atmosphere. Black-Right-Pointing-Pointer Oxygen inward diffusion was dominated by lattice diffusion.

  10. The potential capacities of Ta'ziyeh in Modern Imagism

    Directory of Open Access Journals (Sweden)

    A.M Nedai

    2009-03-01

    Full Text Available Ta'ziyeh as the most important method in religious and ritual theatre in Iran has many capabilities which can be used in modern visualization. The only element in this theatre which has been studied is distancing in performance styles. But by studying the existent versions of Ta'ziyehs, there are other elements for recognition and use, which has not still been studied. The relationship between religious and ritual theatre with Ta'ziyeh and also their main themes helps to identify these elements and their capabilities. Meanwhile, the presence of music as an expressive and performing element provides a basis which can be used in finding a new manner of expression in visual/dramatic works (such as music videos. Studying on such elements as time-place interlace, character replacement, functions of music, and their effects on audiences, shows that Ta'ziyeh has specific capabilities in visualization (even in Cinema and Media. This article, through capitalizing on this subject and introducing one paradigm (Moses and poor Pilgrim, and comparing two versions of it, tries to represent these capabilities, and illuminates Ta'ziyeh's abilities for modern (and even postmodern visualization.

  11. Gold nanoparticles embedded in Ta 2 O 5 /Ta 3 N 5 as active visible-light plasmonic photocatalysts for solar hydrogen evolution

    KAUST Repository

    Luo, Yujing; Liu, Xiaoming; Tang, Xinghua; Luo, Yan; Zeng, Qianyao; Deng, Xiaolei; Ding, Shaolei; Sun, Yiqun

    2014-01-01

    Here, we demonstrate a new recreating photocatalytic activity of a Nano Au/Ta2O5 composite for hydrogen evolution from water as a visible-light-responsive plasmonic photocatalyst by embedding Au nanoparticles in a Ta2O5 host lattice. The Nano Au/Ta2

  12. 75 FR 43564 - TA-W-71,483, Continental Airlines, Inc., Reservations Division, Houston, TX; TA-W-71,483A...

    Science.gov (United States)

    2010-07-26

    ... DEPARTMENT OF LABOR Employment and Training Administration TA-W-71,483, Continental Airlines, Inc., Reservations Division, Houston, TX; TA-W-71,483A, Continental Airlines, Inc., Reservations Division, Tampa, FL; TA-W-71,483B, Continental Airlines, Inc., Reservations Division, Salt Lake City, UT; Notice of...

  13. Micro-patterning of NdFeB and SmCo magnet films for integration into micro-electro-mechanical-systems

    International Nuclear Information System (INIS)

    Walther, A.; Marcoux, C.; Desloges, B.; Grechishkin, R.; Givord, D.; Dempsey, N.M.

    2009-01-01

    The integration of high-performance RE-TM (NdFeB and SmCo) hard magnetic films into micro-electro-mechanical-systems (MEMS) requires their patterning at the micron scale. In this paper we report on the applicability of standard micro-fabrication steps (film deposition onto topographically patterned substrates, wet etching and planarization) to the patterning of 5-8 μm thick RE-TM films. While NdFeB comprehensively fills micron-scaled trenches in patterned substrates, SmCo deposits are characterized by poor filling of the trench corners, which poses a problem for further processing by planarization. The magnetic hysteresis loops of both the NdFeB and SmCo patterned films are comparable to those of non-patterned films prepared under the same deposition/annealing conditions. A micron-scaled multipole magnetic field pattern is directly produced by the unidirectional magnetization of the patterned films. NdFeB and SmCo show similar behavior when wet etched in an amorphous state: etch rates of approximately 1.25 μm/min and vertical side walls which may be attributed to a large lateral over-etch of typically 20 μm. Chemical-mechanical-planarization (CMP) produced material removal rates of 0.5-3 μm/min for amorphous NdFeB. Ar ion etching of such films followed by the deposition of a Ta layer prior to film crystallization prevented degradation in magnetic properties compared to non-patterned films

  14. Micro-patterning of NdFeB and SmCo magnet films for integration into micro-electro-mechanical-systems

    Energy Technology Data Exchange (ETDEWEB)

    Walther, A. [CEA Leti-MINATEC, 17 rue des Martyrs, 38054 Grenoble (France); Institut Neel, CNRS-UJF, 25 rue des Martyrs, 38042 Grenoble (France); Marcoux, C.; Desloges, B. [CEA Leti-MINATEC, 17 rue des Martyrs, 38054 Grenoble (France); Grechishkin, R. [Laboratory of Magnetoelectronics, Tver State University, 170000 Tver (Russian Federation); Givord, D. [Institut Neel, CNRS-UJF, 25 rue des Martyrs, 38042 Grenoble (France); Dempsey, N.M. [Institut Neel, CNRS-UJF, 25 rue des Martyrs, 38042 Grenoble (France)], E-mail: nora.dempsey@grenoble.cnrs.fr

    2009-03-15

    The integration of high-performance RE-TM (NdFeB and SmCo) hard magnetic films into micro-electro-mechanical-systems (MEMS) requires their patterning at the micron scale. In this paper we report on the applicability of standard micro-fabrication steps (film deposition onto topographically patterned substrates, wet etching and planarization) to the patterning of 5-8 {mu}m thick RE-TM films. While NdFeB comprehensively fills micron-scaled trenches in patterned substrates, SmCo deposits are characterized by poor filling of the trench corners, which poses a problem for further processing by planarization. The magnetic hysteresis loops of both the NdFeB and SmCo patterned films are comparable to those of non-patterned films prepared under the same deposition/annealing conditions. A micron-scaled multipole magnetic field pattern is directly produced by the unidirectional magnetization of the patterned films. NdFeB and SmCo show similar behavior when wet etched in an amorphous state: etch rates of approximately 1.25 {mu}m/min and vertical side walls which may be attributed to a large lateral over-etch of typically 20 {mu}m. Chemical-mechanical-planarization (CMP) produced material removal rates of 0.5-3 {mu}m/min for amorphous NdFeB. Ar ion etching of such films followed by the deposition of a Ta layer prior to film crystallization prevented degradation in magnetic properties compared to non-patterned films.

  15. En rejse i hverdagen - de små skridt

    DEFF Research Database (Denmark)

    Nielsen, Trine Mønsted

    Projektet konkluderer, at der er potentiale for alle små og mellemstore virksomheder (SMV'er) i at arbejde aktivt med bæredygtighed som en del af deres forretningsudvikling. Rapporten indeholder resultater om, hvordan SMV'er arbejder med bæredygtighed, hvilken værdi de får ud af indsatsen og hvil...

  16. Coilin phosphorylation mediates interaction with SMN and SmB′

    Science.gov (United States)

    Toyota, Cory G.; Davis, Misty D.; Cosman, Angela M.; Hebert, Michael D.

    2010-01-01

    Cajal bodies (CBs) are subnuclear domains that participate in spliceosomal small nuclear ribonucleoprotein (snRNP) biogenesis and play a part in the assembly of the spliceosomal complex. The CB marker protein, coilin, interacts with survival of motor neuron (SMN) and Sm proteins. Several coilin phosphoresidues have been identified by mass spectrometric analysis. Phosphorylation of coilin affects its self-interaction and localization in the nucleus. We hypothesize that coilin phosphorylation also impacts its binding to SMN and Sm proteins. In vitro binding studies with a C-terminal fragment of coilin and corresponding phosphomimics show that SMN binds preferentially to dephosphorylated analogs and that SmB′ binds preferentially to phosphomimetic constructs. Bacterially expressed full-length coilin binds more SMN and SmB′ than does the C-terminal fragment. Co-immunoprecipitation and phosphatase experiments show that SMN also binds dephosphorylated coilin in vivo. These data show that phosphorylation of coilin influences interaction with its target proteins and, thus, may be significant in managing the flow of snRNPs through the CB. PMID:19997741

  17. Coilin phosphorylation mediates interaction with SMN and SmB'.

    Science.gov (United States)

    Toyota, Cory G; Davis, Misty D; Cosman, Angela M; Hebert, Michael D

    2010-04-01

    Cajal bodies (CBs) are subnuclear domains that participate in spliceosomal small nuclear ribonucleoprotein (snRNP) biogenesis and play a part in the assembly of the spliceosomal complex. The CB marker protein, coilin, interacts with survival of motor neuron (SMN) and Sm proteins. Several coilin phosphoresidues have been identified by mass spectrometric analysis. Phosphorylation of coilin affects its self-interaction and localization in the nucleus. We hypothesize that coilin phosphorylation also impacts its binding to SMN and Sm proteins. In vitro binding studies with a C-terminal fragment of coilin and corresponding phosphomimics show that SMN binds preferentially to dephosphorylated analogs and that SmB' binds preferentially to phosphomimetic constructs. Bacterially expressed full-length coilin binds more SMN and SmB' than does the C-terminal fragment. Co-immunoprecipitation and phosphatase experiments show that SMN also binds dephosphorylated coilin in vivo. These data show that phosphorylation of coilin influences interaction with its target proteins and, thus, may be significant in managing the flow of snRNPs through the CB.

  18. Perspectives of SM Higgs measurements at the LHC

    Indian Academy of Sciences (India)

    ... where significant signals can be expected from the LHC experiments. The most sensitive LHC Higgs signatures are reviewed and the discovery year is estimated as a function of the Higgs mass. Finally, we give some ideas about: 'What might be known about the production and decays of a SM Higgs boson' after 10 years ...

  19. Discovery of SM Higgs Boson in ATLAS Experiment

    Indian Academy of Sciences (India)

    IAS Admin

    ics, Higgs boson, particle detec- tors, trigger, grid computing. Discovery of SM Higgs Boson in ATLAS Experiment. Prafulla Kumar Behera. Prafulla Kumar Behera is an experimental high energy physicist at the. IITM, Chennai. He has participated in many large-scale collider experiments namely. BELLE at Japan, BABAR.

  20. Perspectives of SM Higgs measurements at the LHC

    Indian Academy of Sciences (India)

    learned at the LHC about the production and decays of a SM Higgs boson. 2. The 'well' known. Recent LHC Higgs cross-section estimates for the different production mechanisms can be found in [8]. By far the largest contribution to the cross-section comes from the gluon– gluon fusion process to top quarks [9], which is ...

  1. Discovery of SM Higgs Boson in ATLAS Experiment

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 18; Issue 3. Discovery of SM Higgs Boson in ATLAS Experiment. Prafulla Kumar Behera. General Article Volume 18 Issue 3 March 2013 pp 248-263. Fulltext. Click here to view fulltext PDF. Permanent link:

  2. 31 CFR 208.5 - Availability of the ETA SM.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Availability of the ETA SM. 208.5 Section 208.5 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE MANAGEMENT OF FEDERAL AGENCY...

  3. Xe-135 and Sm-149 Isotopic Evolution Analysis Xesamo code

    International Nuclear Information System (INIS)

    Caro, R.; Gallego, J.; Martinez Fanegas, R.

    1977-01-01

    In this report the time evolution analysis of the nuclides concentration Xe-135 and Sm-149 as a function of the neutron flux is carried out. The neutron flux may be any function of time. It is analyzed as well the reactivity changes associated with the xenon and samarium concentration variations. (Author) 5 refs

  4. Obtaining strong ferromagnetism in diluted Gd-doped ZnO thin films through controlled Gd-defect complexes

    KAUST Repository

    Roqan, Iman S.

    2015-02-21

    We demonstrate the fabrication of reproducible long-range ferromagnetism (FM) in highly crystalline GdxZn1-xO thin films by controlling the defects. Films are grown on lattice-matched substrates by pulsed laser deposition at low oxygen pressures (≤25 mTorr) and low Gd concentrations (x ≤ 0.009). These films feature strong FM (10 μB per Gd atom) at room temperature. While films deposited at higher oxygen pressure do not exhibit FM, FM is recovered by post-annealing these films under vacuum. These findings reveal the contribution of oxygen deficiency defects to the long-range FM. We demonstrate the possible FM mechanisms, which are confirmed by density functional theory study, and show that Gd dopants are essential for establishing FM that is induced by intrinsic defects in these films.

  5. Obtaining strong ferromagnetism in diluted Gd-doped ZnO thin films through controlled Gd-defect complexes

    KAUST Repository

    Roqan, Iman S.; Venkatesh, S.; Zhang, Z.; Hussain, S.; Bantounas, Ioannis; Franklin, J. B.; Flemban, Tahani H.; Zou, B.; Lee, J.-S.; Schwingenschlö gl, Udo; Petrov, P. K.; Ryan, M. P.; Alford, N. M.

    2015-01-01

    We demonstrate the fabrication of reproducible long-range ferromagnetism (FM) in highly crystalline GdxZn1-xO thin films by controlling the defects. Films are grown on lattice-matched substrates by pulsed laser deposition at low oxygen pressures (≤25 mTorr) and low Gd concentrations (x ≤ 0.009). These films feature strong FM (10 μB per Gd atom) at room temperature. While films deposited at higher oxygen pressure do not exhibit FM, FM is recovered by post-annealing these films under vacuum. These findings reveal the contribution of oxygen deficiency defects to the long-range FM. We demonstrate the possible FM mechanisms, which are confirmed by density functional theory study, and show that Gd dopants are essential for establishing FM that is induced by intrinsic defects in these films.

  6. Fabrication of single-grain GdBa 2 Cu 3 O 7− bulk ...

    Indian Academy of Sciences (India)

    Research Articles Volume 74 Issue 5 May 2010 pp 827-832 ... Superconductors; top seeded infiltration and growth process; GdBa2 ... The morphology, microstructure and levitation force of the bulk GdBCO have also been investigated.

  7. Data of evolutionary structure change: 1RAAA-3GD5C [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1RAAA-3GD5C 1RAA 3GD5 A C ANPLYQKHIISINDLSRDDLNLVLATAAKLKANPQPELL...LRDPFEAARGAHILYTDVWTHRLQLFEQYQINAALLN--------------CAAAEAIVLHCLPAHRGEEITDEVMEGPRS... 0 1RAA A 1RAAAA 1RAAA PLPRV--DEIAT...Chain> 1RAA A 1RAAA

  8. Data of evolutionary structure change: 1RAAA-3GD5D [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1RAAA-3GD5D 1RAA 3GD5 A D ANPLYQKHIISINDLSRDDLNLVLATAAKLKANPQPELL...RDPFEAARGAHILYTDVWTHRLQLFEQYQINAAL-----------LNC--AAAEAIVLHCLPAHRGEEITDEVMEGPRSRI... 0 1RAA A 1RAAA...RAA A 1RAAA P...ine> 1RAA A 1RAAA

  9. Magnetic anisotropies in SmCo thin films

    International Nuclear Information System (INIS)

    Chen, K.

    1993-01-01

    A systemic study of the deposition processes and magnetic properties for the Sm-Co film system has been carried out. Films of Sm-Co system with various magnetic anisotropies have been synthesized through sputter deposition in both crystalline and amorphous phases. The origins of various anisotropies have been studied. Thermalized sputter deposition process control was used to synthesize Fe enriched Sm-Co films with rhombohedral Th 2 Zn 17 type structure. The film exhibited unusually strong textures with the crystallographic c axes of the crystallites aligned in the film plane. A large anisotropy was resulted with easy axis in the film plane. A well defined and large in-the-film-plane anisotropy of exceptionally high value of 3.3 x 10 6 erg/cm 3 has been obtained in the amorphous SmCo films by applying a magnetic field in the film plane during deposition. It was found that the in-the-film-plane anisotropy depended essentially on the applied field and Sm concentration. For films not synthesized through thermallized sputtering, the easy axis of the film could reoriented. A perpendicular anisotropy was also presented in the film synthesized through thermallized sputtering deposition. A large in-plane anisotropy was obtained in films deposited above ambient temperatures. It was concluded that the surface induced short range ordering was the origin of the in-the-film-phase anisotropy observed in amorphous film deposited in the presence of a magnetic field. The formation mechanism was different from that of the short range ordering induced by field annealing. The perpendicular anisotropy was shown to be growth induced. Large in-plane anisotropy in amorphous films was resulted form partial crystallization in the film. Both the formation of growth induced structure and partial crystallization in the film prevented the formation of the pair ordering and decreased in-the-film-plane anisotropy

  10. Studies concerning the preparation of the 153Sm complex with EDTMP (ethylenediaminetetra methylenephosphonic acid) and other 153Sm complexes with other phosphonates, at room temperature

    International Nuclear Information System (INIS)

    Gasiglia, Haroldo Taurian

    2000-01-01

    This work presents a study on the preparation of the complexes 1 53S m - EDTMP, 153 Sm - HEDP, 153 Sm - NTMP, 153 Sm - DTPMP and 153 Sm - HDTMP at room temperature. The preparation of the complex 153 Sm - HDTMP, under heating (70 - 72 deg C), was also studied. Several factors affecting the 153 Sm - EDTMP complexing yields were studied, due to its importance for use in Nuclear Medicine. These factors were: the molar ratio [ligand] / [metal], the ligand concentration and the incubation time of the mixture ligand-metal. The preparation of this complex, in low molar ratios, was also investigated. A study of the 153 Sm - EDTMP concerning the 'in vitro' stability, when this complex was prepared in low radioactive concentrations was performed. A study on the temperature influence on its degradation, when this complex was obtained in higher radioactive concentrations, was also performed. The preparation of the complexes 153 Sm - HEDP, 153 Sm - NTMP, 153 Sm - DTPMP and 153 Sm - HDTMP was investigated by preparing the complexes in two situations: high molar ratio and ligand concentration and low molar ratio and ligand concentration. The 'in vitro' stability of each complex, obtained in low radioactive concentration was studied. In the specific case of the complex 153 Sm - HDTMP, its biological distribution in mice was performed. All the complexes were investigated by high performance liquid chromatography (HPLC) and its complexing yields were determined by other three chromatographic processes: ionic exchange, thin layer chromatography (TLC - SG) and paper chromatography. The chromatographic processes were performed by association with specific radiochemical techniques. This work also presents a comparative study on the chromatograms obtained by thin layer chromatography (TLC - SG) and paper chromatography, when evaluated by the technique of cutting the strips into pieces and the chromatograms performed directly on a radiochromatography. The shape of the chromatograms and R

  11. Orange and reddish-orange light emitting phosphors: Sm{sup 3+} and Sm{sup 3+}/Eu{sup 3+} doped zinc phosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Meza-Rocha, A.N., E-mail: ameza@fis.cinvestav.mx [Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, P.O. Box 55-534, 09340 México D.F., México (Mexico); Speghini, A. [Dipartimento di Biotecnologie, Universita di Verona and INSTM, UdR Verona, Strada Le Grazie 15, I-37314 Verona (Italy); IFAC CNR, Nello Carrara Institute of Applied Physics, MDF Lab, I-50019 Sesto Fiorentino, FI (Italy); Bettinelli, M. [Dipartimento di Biotecnologie, Universita di Verona and INSTM, UdR Verona, Strada Le Grazie 15, I-37314 Verona (Italy); Caldiño, U. [Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, P.O. Box 55-534, 09340 México D.F., México (Mexico)

    2015-11-15

    A spectroscopy study of Sm{sup 3+} and Sm{sup 3+}/Eu{sup 3+} doped zinc phosphate glasses is performed through photoluminescence spectra and decay time profile measurements. Under Sm{sup 3+} excitation at 344 nm, the Sm{sup 3+} singly doped glass shows an orange global emission with x=0.579 and y=0.414 CIE1931 chromaticity coordinates, whereas the Sm{sup 3+}/Eu{sup 3+} co-doped sample exhibits orange overall emissions (x=0.581 and y=0.398, and x=0.595 and y=0.387) and reddish-orange overall emission (x=0.634 and y=0.355) upon excitations at 344, 360 and 393 nm, respectively. Such luminescence from the co-doped sample is originated by the simultaneous emission of Sm{sup 3+} and Eu{sup 3+}. Under Sm{sup 3+} excitation at 344 and 360 nm, the Eu{sup 3+} emission is sensitized and enhanced by Sm{sup 3+} through a non-radiative energy transfer process. The non-radiative nature was inferred from the shortening of the Sm{sup 3+} lifetime observed in the Sm{sup 3+}/Eu{sup 3+} co-doped sample. An analysis of the Sm{sup 3+} emission decay time profiles using the Inokuti–Hirayama model suggests that an electric quadrupole–quadrupole interaction into Sm–Eu clusters might dominate the energy transfer process, with an efficiency of 0.17. - Highlights: • Zinc phosphate glasses are optically activated with Sm{sup 3+}/Eu{sup 3+} (ZPOSmEu). • Non-radiative energy transfer Sm{sup 3+}→Eu{sup 3+} takes place in ZPOSmEu. • ZPOSmEu overall emission can be modulated with the excitation wavelength. • ZPOSmEu might be useful as orange/reddish-orange phosphor for UV-white LEDs.

  12. Redetermination of Na(3)TaF(8).

    Science.gov (United States)

    Langer, Vratislav; Smrcok, Lubomír; Boca, Miroslav

    2010-09-01

    The crystal structure of trisodium octafluoridotantalate, Na(3)TaF(8), has been redetermined using diffractometer data collected at 153 K, resulting in more accurate bond distances and angles than obtained from a previous structure determination based on film data. The structure is built from layers running along [101], which are formed by distorted [TaF(8)] antiprisms and [NaF(6)] rectangular bipyramids sharing edges and corners. The individual layers are separated by eight-coordinated Na ions. Two atoms in the asymmetric unit are in special positions: the Ta atom is on a twofold axis in Wyckoff position 4e and one of the Na ions lies on an inversion centre in Wyckoff site 4d.

  13. FLEKSIGURNOST I (DEREGULACIJA TRŽIŠTA RADA

    Directory of Open Access Journals (Sweden)

    Sandra Laleta

    2016-01-01

    Full Text Available Predmet su ovoga rada radni odnosi i tržište rada u kontekstu fleksigurnosti. U radu se analizira novi vladavinski model, soft law, otvorene metode koordina- cije, europski socijalni model, inkluzivnost, kategorije koje su neraskidivo vezane uz fleksigurnost, radne odnose i tržište rada. Istražena su njihova obilježja i utjecaj na supranacionalnu regulativu, usporednopravna i hrvatska rješenja. Daje se i raščlamba nekih novih instituta tržišta rada (novi oblici uređenja radnog vremena, agencijski rad, mini-jobs. Poseban dio rada čini istraživanje (dereguliranja tržišta rada, novih modela zapošljavanja, kao i fleksigurnosti i hrvatskoga tržišta rada de lege lata te se daju prijedlozi de lege ferenda.

  14. Microstructural evolution and creep of Fe-Al-Ta alloys

    Energy Technology Data Exchange (ETDEWEB)

    Prokopcakova, Petra; Svec, Martin [Technical University of Liberec (Czech Republic). Dept. of Material Science; Palm, Martin [Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany). Structure and Nano-/Micromechanics of Materials

    2016-05-15

    The microstructural evolution in Fe-Al-Ta alloys containing 23 - 31 at.% Al and 1.5 - 2.2 at.% Ta has been studied in the temperature range 650 - 750 C by annealing for 1, 10, 100 and 1 000 h. The experiments confirm that in this temperature range the precipitation of the stable hexagonal C14 Laves phase is preceded by formation of coherent, metastable L2{sub 1} Heusler phase precipitates within the Fe-Al matrix. However, precipitates of C14 are observed after much shorter annealing times than previously assumed. Creep strength increases substantially with increasing Al content of the alloys because the solid solubility for Ta in the Fe-Al matrix increases with increasing Al content and solid-solution hardening contributes substantially to the observed high creep strength. It may therefore be that the microstructural changes during creep have no noticeable effect on creep strength.

  15. Microstructural evolution and creep of Fe-Al-Ta alloys

    International Nuclear Information System (INIS)

    Prokopcakova, Petra; Svec, Martin; Palm, Martin

    2016-01-01

    The microstructural evolution in Fe-Al-Ta alloys containing 23 - 31 at.% Al and 1.5 - 2.2 at.% Ta has been studied in the temperature range 650 - 750 C by annealing for 1, 10, 100 and 1 000 h. The experiments confirm that in this temperature range the precipitation of the stable hexagonal C14 Laves phase is preceded by formation of coherent, metastable L2 1 Heusler phase precipitates within the Fe-Al matrix. However, precipitates of C14 are observed after much shorter annealing times than previously assumed. Creep strength increases substantially with increasing Al content of the alloys because the solid solubility for Ta in the Fe-Al matrix increases with increasing Al content and solid-solution hardening contributes substantially to the observed high creep strength. It may therefore be that the microstructural changes during creep have no noticeable effect on creep strength.

  16. Method of treating Ti--Nb--Zr--Ta superconducting alloys

    International Nuclear Information System (INIS)

    Horiuchi, T.; Monju, Y.; Tatara, I.; Nagai, N.; Hisata, M.; Matsumoto, K.

    1975-01-01

    A superconducting alloy is formulated from 10 to 50 at. percent Ti, 20 to 50 at. percent Nb, 10 to 40 at. percent Zr, and 5 to 12 at. percent Ta. A Ti--Nb--Zr--Ta superconducting alloy with a fine, non-homogeneous structure is obtained by forming a β solid solution of Ti--Nb--Zr--Ta alloy by heating to a temperature within the β solid solution range, cooling, and then cold working the heated alloy. The cold worked alloy is heated to a temperature within the (β' + β'') alloy to maintain the peritectoid structure, cold worked, then heated to a temperature within the eutectoid range to form a multiphase alloy structure and then cooled and finally cold worked. (U.S.)

  17. (Gd1−xErx)5Si2Ge2 compounds

    Indian Academy of Sciences (India)

    Gd metal (3 N) by arc melting, and then annealed at 1523 K (3 h). The phase, microstructure, Curie ... The temperature of magnetic transition decreases linearly from 281 K to 177 K with the increase of Er content from x = 0–0·2. ... Gd5Si2Ge2 serial compounds, different rare earth elements substituted for Gd in Gd5(Six ...

  18. Study on the Mechanical Properties and Corrosion Behaviors of Fe-(20, 45) wt%Gd Intermetallics

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Bo Kyeong; Baik, Youl; Choi, Yong [Dankook University, Chungnam (Korea, Republic of); Moon, Byung Moon [Korea Institute of Industrial Technology, Incheon (Korea, Republic of)

    2017-02-15

    Fe-(20, 45 wt%) Gd intermetallics were vacuum arc melted as the mother alloy of a neutron shielding and absorbing material. The structure of the cast Fe-20 wt%Gd intermetallics had primary dendrites with a short width of about 2 μm, which became coarse with increasing Gd content. The final compositions of the Fe-20 wt%Gd and Fe-45 wt%Gd intermetallics determined by Rietveld refinement were mainly Fe{sub 3}Gd with 26.6 at%Fe{sub 2}Gd, and Fe{sub 3}Gd with various intermetallics like 13.9 at%Fe{sub 2}Gd, 7.3 at%Fe{sub 9}Gd and 3.9 at%Fe{sub 17}Gd{sub 2}, respectively. The micro-hardnesses, yield strength, ultimate compressive strength and elongation of the Fe-20 wt%Gd intermetallics were 629±12 Hv, 753 MPa, 785 MPa and 4%, respectively, and those of the Fe-45 wt%Gd intermetallics were 741±13 Hv, 772 MPa, 823 MPa and 3%. Passivity was not present in artificial sea water at room temperature. The corrosion potentials and the corrosion rates of the Fe-20 wt%Gd and Fe-45 wt%Gd intermetallics were –624 mV{sub SHE}, 2.771 mA/cm{sup 2} , and –804 mV{sub SHE}, 3.397 mA/cm{sup 2} , respectively. The corroded surface of the Fe-Gd intermetallics contained corrosion products like gadolinium with iron, which detached to leave a trail of pits.

  19. Cloning and Functional Analysis of MADS-box Genes, TaAG-A and TaAG-B, from a Wheat K-type Cytoplasmic Male Sterile Line

    Directory of Open Access Journals (Sweden)

    Wenlong Yang

    2017-06-01

    Full Text Available Wheat (Triticum aestivum L. is a major crop worldwide. The utilization of heterosis is a promising approach to improve the yield and quality of wheat. Although there have been many studies on wheat cytoplasmic male sterility, its mechanism remains unclear. In this study, we identified two MADS-box genes from a wheat K-type cytoplasmic male sterile (CMS line using homology-based cloning. These genes were localized on wheat chromosomes 3A and 3B and named TaAG-A and TaAG-B, respectively. Analysis of TaAG-A and TaAG-B expression patterns in leaves, spikes, roots, and stems of Chinese Spring wheat determined using quantitative RT-PCR revealed different expression levels in different tissues. TaAG-A had relatively high expression levels in leaves and spikes, but low levels in roots, while TaAG-B had relatively high expression levels in spikes and lower expression in roots, stems, and leaves. Both genes showed downregulation during the mononucleate to trinucleate stages of pollen development in the maintainer line. In contrast, upregulation of TaAG-B was observed in the CMS line. The transcript levels of the two genes were clearly higher in the CMS line compared to the maintainer line at the trinucleate stage. Overexpression of TaAG-A and TaAG-B in Arabidopsis resulted in phenotypes with earlier reproductive development, premature mortality, and abnormal buds, stamens, and stigmas. Overexpression of TaAG-A and TaAG-B gives rise to mutants with many deformities. Silencing TaAG-A and TaAG-B in a fertile wheat line using the virus-induced gene silencing (VIGS method resulted in plants with green and yellow striped leaves, emaciated spikes, and decreased selfing seed set rates. These results demonstrate that TaAG-A and TaAG-B may play a role in male sterility in the wheat CMS line.

  20. Simplified syntheses of the water-soluble chiral shift reagents Sm-(R)-pdta and Sm-(S)-pdta

    Czech Academy of Sciences Publication Activity Database

    Hrubá, L.; Buděšínský, Miloš; Pícha, Jan; Jiráček, Jiří; Vaněk, Václav

    2013-01-01

    Roč. 54, č. 47 (2013), s. 6296-6297 ISSN 0040-4039 Institutional support: RVO:61388963 Keywords : NMR * chiral shift reagents * Sm-pdta * PDTA * samarium * 1,2-diaminopropane Subject RIV: CC - Organic Chemistry Impact factor: 2.391, year: 2013