Measurement of cross sections producing short-lived nuclei by 14 MeV neutron. Br, Te, Dy, Ho, Yb

Energy Technology Data Exchange (ETDEWEB)

Sakane, H.; Matsumoto, T.; Yamamoto, H.; Kawade, K. [Nagoya Univ. (Japan); Iida, T.; Takahashi, A.

1997-03-01

Nine neutron activation cross sections producing the nuclei with half-lives between 2 min and 57 min have been measured at energy range between 13.4 and 14.9 MeV for Br, Te, Dy, Ho, Yb. The cross sections of {sup 81}Br(n,p){sup 81m}Se, {sup 128}Te(n,p){sup 128m}Sb, {sup 128}Te(n,{alpha}){sup 125m}Sn, {sup 164}Dy(n,p){sup 164}Tb, {sup 165}Ho(n,{alpha}){sup 162}Tb, {sup 176}Yb(n,p){sup 176}Tm were newly obtained at the six energy points between 13.4-14.9 MeV, although the previous results have been obtained at one energy point. {sup 79}Br(n,2n){sup 78}Br, {sup 164}Dy(n,p){sup 164}Tb are compared with evaluated data of JENDL-3.2. The evaluations for these reactions agree reasonably well with experimental results. The cross sections of (n,p) reaction are compared with systematics by Kasugai et. al. The systematics agrees with experimental results. (author)

RNi2B2C (R = Ho, Dy, Tb and Pr) single crystals grown by the cold copper crucible method

Science.gov (United States)

Durán, A.; Munoz, E.; Bernès, S.; Escudero, R.

2000-08-01

Single crystals of RNi2B2C (R = Ho, Dy, Tb, Pr) have been grown on cold copper crucibles in a high-frequency induction furnace. As a result, shiny metallic and brittle platelike single crystals were obtained. They were examined by x-ray and scanning electron microscopy with WDX/EDX for local composition analysis and show a very good crystallographic structure and compositions. Resistivity and dc magnetic measurements were performed to study superconducting and magnetic properties. Besides known electronic properties of the RNi2B2C family, we report for the first time results for PrNi2B2C single crystals successfully obtained by this technique.

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

Spin reorientation phenomena in (R{sub 1-x}R`{sub x}){sub 2}Co{sub 14}B (R = La, R` = Dy and Ho)

Energy Technology Data Exchange (ETDEWEB)

Myojin, T. [Takamatsu Nat. Coll. of Technol. (Japan); Ohno, T. [Tokushima Univ. (Japan). Faculty of Engineering; Mizuno, K. [Tokushima Univ. (Japan). Faculty of Integrated Arts and Sciences; Tsujimura, A. [Faculty of Engineering, Tokushima Bunri Univ., Kagawa Shido (Japan); Kojima, K. [Hiroshima Univ. (Japan). Faculty of Integrated Arts and Sciences

1997-07-01

The variations of magnetization with temperature in (La{sub 1-x}R`{sub x}){sub 2}Co{sub 14}B (R` = Dy and Ho) have been measured to determine spin reorientation temperature T{sub SR} of these compounds. The phase diagrams of spin arrangement thus obtained indicate monotonous increase in T{sub SR} with R` concentration x. Also, T{sub SR}`s of R{sub 2}Co{sub 14}B(R = Tb, Dy and Ho) are found to vary linearly with the Stevens factor {alpha} of R. (orig.). 4 refs.

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

Effects of pressure and magnetic field on transport properties of Y1-xRxCo2 alloys (R=Gd, Tb, Dy, Ho and Er)

International Nuclear Information System (INIS)

Takaesu, Y; Nakama, T; Kinjyo, A; Yonamine, S; Hedo, M; Yagasaki, K; Uchima, K; Uwatoko, Y; Burkov, A T

2010-01-01

Electrical resistivity ρ and thermopower S of Y 1-x R x Co 2 (R=Gd, Tb, Dy, Ho and Er) Laves phase alloy systems were measured at temperatures from 1.5 K to 300 K in magnetic fields up to 15 T and under hydrostatic pressure up to 2 GPa. We show that there is a universal linear relation between the pressure and magnetic field derivatives of the resistivity, dρ/dP and dρ/dB, with gradient, determined by pressure derivative of the critical metamagnetic field of the cobalt 3d electron system. A similar scaling behavior was found for the thermopower dependencies on pressure and alloy composition.

Magnetostriction of Tb-Dy-Fe crystals

International Nuclear Information System (INIS)

Mei Wu; Okane, T.; Umeda, T.

1998-01-01

left angle 111 right angle -oriented twin free Tb-Dy-Fe single crystals, left angle 112 right angle - and left angle 110 right angle -oriented twinned ''single'' Tb-Dy-Fe crystals were prepared using floating zone melting crystal growth methods. Magnetostrictive performances of the crystals were investigated. Better low-field properties were observed in the left angle 110 right angle twinned crystals than in the left angle 112 right angle crystals. The highest properties were achieved in the left angle 111 right angle twin free single crystals. Even though there were still oxidized particles in the present left angle 111 right angle single crystals, a large magnetostrictive jump of 1700 ppm and a very low saturation magnetic field of 500 Oe were obtained. To understand magnetization and magnetostriction of different Tb-Dy-Fe crystals, theoretical modeling was carried out based on a simplified domain rotation model. Magnetization moment rotation paths of different domains were simulated and hence the resultant magnetostriction was obtained, which could adequately account for the experimental results of different crystals. The limitation of the domain rotation model was also discussed. (orig.)

A single crystal study of RE{sub 14}Co{sub 3}In{sub 3} (RE = Y, Tb, Dy, Ho, Er)

Energy Technology Data Exchange (ETDEWEB)

Zaremba, V.I.; Kalychak, Y.M.; Dzevenko, M.V. [Inorganic Chemistry Dept., Ivan Franko National Univ. of Lviv (Ukraine); Rodewald, U.Ch.; Heying, B.; Poettgen, R. [Inst. fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Univ. Muenster (Germany)

2006-01-01

The rare earth-cobalt-indides RE{sub 14}Co{sub 3}In{sub 3} (RE = Y, Tb, Dy, Ho, Er) were prepared in polycrystalline form from the elements by arc-melting. Small single crystals were grown through a special annealing sequence. The compounds were investigated on the basis of X-ray powder and single crystal data: Lu{sub 14}Co{sub 2}In{sub 3} (Gd{sub 14}Co{sub 3}In{sub 2.7}) type, P4{sub 2}/nmc, Z = 4, a = 959.0(1), c = 2319.1(5) pm, wR2 = 0.055, 2289 F{sup 2} values, 65 variables for Y{sub 13.90}Co{sub 2.99}In{sub 3.02}, a = 953.8(1), c = 2315.8(5) pm, wR2 = 0.108, 2357 F{sup 2} values, 65 variables for Tb{sub 13.92}Co{sub 3.01}In{sub 2.92}, a = 949.24(3), c = 2296.5(1) pm, wR2 = 0.129, 2518 F{sup 2} values, 65 variables for Dy{sub 13.90}Co{sub 2.97}In{sub 2.95}, a = 946.3(1), c = 2289.0(5) pm, wR2 = 0.099, 2297 F{sup 2} values, 64 variables for Ho{sub 14}Co{sub 2.80}In{sub 2.89}, and a = 941.0(1), c = 2274.2(5) pm, wR2 = 0.140, 2450 F{sup 2} values, 65 variables for Er{sub 13.83}Co{sub 2.88}In{sub 3.10}. All RE{sub 14}Co{sub 3}In{sub 3} indides show a small degree of In/Co mixing (between 7 and 16% Co) on the 4c In1 site and defects on the 8g Co1 positions (between 84 and 95% Co). Except for the holmium compound, the RE{sub 14}Co{sub 3}In{sub 3} intermetallics also reveal RE/In mixing on the 4c RE1 sites, leading to the refined compositions. The seven crystallographically independent RE sites have between 9 and 10 nearest RE neighbors. The RE{sub 14}Co{sub 3}In{sub 3} structures consist of a complex intergrowth of rare earth based polyhedra. Both cobalt sites have a distorted trigonal-prismatic rare earth coordination. An interesting feature is the In2-In2 dumb-bell with an In2-In2 distance of 300 pm (for Ho{sub 14}Co{sub 2.80}In{sub 2.89}). The crystal chemistry of the RE{sub 14}Co{sub 3}In{sub 3} indides is discussed. (orig.)

Superdeformation studies in {sup 150}Tb and {sup 153}Ho

Energy Technology Data Exchange (ETDEWEB)

Nisius, D.; Janssens, R.V.F.; Crowell, B. [and others

1995-08-01

There are now over 40 superdeformed (SD) bands known in the A {approximately} 150 region and in most cases the properties of these bands are understood in terms of single-particle excitations in the absence of pairing. By continuing the search for new SD bands we hope to gain insight into (1) the ordering of the proton and neutron orbitals near the Fermi surface in the SD well, (2) the effects that the alignment of those orbitals has on the moments of inertia, and (3) the collective excitations in the SD well. For {sup 150}Tb, which is one proton and one neutron away from the SD doubly-magic nucleus {sup 152}Dy, it should be possible to study SD bands based on both proton and neutron hole excitations. By adding one proton to the {sup 152}Dy nucleus (i.e. {sup 153}Ho) proton excitations above the Z = 66 shell gap can be studied. These excitations are important as calculations suggested that the proton intruder orbital N = 7 might become occupied. Interactions between this orbital and a N = 5 level may result in softness towards octupole vibrations. High spin states in {sup 150}Th and {sup 153}Ho were populated using the {sup 124}Sn({sup 31}P,5n) and {sup 120}Sn({sup 37}Cl,4n) reactions, respectively. In both cases the early implementation phase of Gammasphere was used to detect the decay gamma rays and over 1 x 10{sup 9} triple and higher fold coincidence events were recorded. In {sup 150}Tb, the data analysis is complete and two new SD bands were identified. The fact that Im{sup (2)} moments of inertia are sensitive to the specific high-N intruder content of the SD bands was used to suggest configurations for the two new bands. A paper reporting these results is being prepared. For {sup 153}Ho, data analysis is still in its early stages.

Eu-, Tb-, and Dy-Doped Oxyfluoride Silicate Glasses for LED Applications

DEFF Research Database (Denmark)

Zhu, C.F.; Wang, J.; Zhang, M.M.

2014-01-01

Luminescence glass is a potential candidate for the light-emitting diodes (LEDs) applications. Here, we study the structural and optical properties of the Eu-, Tb-, and Dy-doped oxyfluoride silicate glasses for LEDs by means of X-ray diffraction, photoluminescence spectra, Commission Internationale...... de L’Eclairage (CIE) chromaticity coordinates, and correlated color temperatures (CCTs). The results show that the white light emission can be achieved in Eu/Tb/Dy codoped oxyfluoride silicate glasses under excitation by near-ultraviolet light due to the simultaneous generation of blue, green, yellow......, and red-light wavelengths from Tb, Dy, and Eu ions. The optical performances can be tuned by varying the glass composition and excitation wavelength. Furthermore, we observed a remarkable emission spectral change for the Tb3+ single-doped oxyfluoride silicate glasses. The 5D3 emission of Tb3+ can...

A critical scattering study of the helical antiferromagnets Ho and Dy

International Nuclear Information System (INIS)

Gaulin, B.D.; Hagen, M.; Child, H.R.

1988-01-01

We have measured the frequency integrated magnetic critical scattering of neutrons from paramagnetic Dy and Ho. Analysis of these data show the paramagnetic to helical antiferromagnetic phase transitions are characterized by the critical exponents ν = 0.57 +- 0.05 and γ = 1.05 = +- .07 for Dy and ν = 0.57 +- .04 and γ = 1.14 = +- .10 for Ho. 3 refs., 2 figs., 1 tab

Slow magnetic relaxation and single-molecule toroidal behaviour in a family of heptanuclear {Cr"I"I"ILn"I"I"I_6} (Ln=Tb, Ho, Er) complexes

Energy Technology Data Exchange (ETDEWEB)

Vignesh, Kuduva R. [IITB-Monash Research Academy, IIT Bombay, Powai, Mumbai (India); Langley, Stuart K. [School of Science and the Environment, Division of Chemistry, Manchester Metropolitan University, Manchester (United Kingdom); Swain, Abinash; Rajaraman, Gopalan [Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai (India); Moubaraki, Boujemaa; Murray, Keith S. [School of Chemistry, Monash University, Clayton, VIC (Australia); Damjanovic, Marko; Wernsdorfer, Wolfgang [Institute Neel, CNRS, Universite Grenoble Alpes, Grenoble (France); Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany)

2018-01-15

The synthesis, magnetic properties, and theoretical studies of three heterometallic {Cr"I"I"ILn"I"I"I_6} (Ln=Tb, Ho, Er) complexes, each containing a metal topology consisting of two Ln{sub 3} triangles connected via a Cr{sup III} linker, are reported. The {CrTb_6} and {CrEr_6} analogues display slow relaxation of magnetization in a 3000 Oe static magnetic field. Single-crystal measurements reveal opening up of the hysteresis loop for {CrTb_6} and {CrHo_6} molecules at low temperatures. Ab initio calculations predict toroidal magnetic moments in the two Ln{sub 3} triangles, which are found to couple, stabilizing a con-rotating ferrotoroidal ground state in Tb and Ho examples and extend the possibility of observing toroidal behaviour in non Dy{sup III} complexes for the first time. (copyright 2018 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

Investigation of complexes with bone affinity using the In vivo generator system 166 Dy/166 Ho

International Nuclear Information System (INIS)

Pedraza L, M.

2006-01-01

The importance of this original research lies in the fact that it has proven that the [ 166 Dy]Dy/ 166 Ho-EDTMP in vivo generator system is a stable complex that can be used as a therapeutic radiopharmaceutical. Multiple myeloma and other hematological malignancies have been treated by myeloablative radiotherapy/chemotherapy and subsequent stem cell transplantation. Bone-seeking radiopharmaceuticals such as 166 Ho-DOTMP or 153 Sm-DTMP, have been proposed for delivering ablative radiation doses to marrow in multiple myeloma and other hematological malignancies or have shown excellent results in palliative bone metastasis pain therapy, respectively. As lanthanides have similar chemical characteristics the phosphonate with bone affinity (EDTMP) labeled with Dy/Ho can be used for marrow ablation while causing minimal irradiation to normal organs. This in vivo generator system has not been previously reported. The aim of this research was to label EDTMP (ethylene diamine tetramethylene phosphonate) with 166 Dy/ 166 Ho; to evaluate the in vitro and in vivo stability of both 166 Dy-EDTMP and 166 Ho-EDTMP complexes when the daughter 166 Ho is formed as a dysprosium decay product; to determine the bone marrow cytotoxic and genotoxic effect in mice and to evaluate, by histopathology, the myeloablative potential of the [ 166 Dy]Dy/ 166 Ho-EDTMP in vivo generator system. 166 Dy was obtained by neutron irradiation of enriched 164 Dy 2 O 3 in a TRIGA Mark III reactor. Labeling was carried out in an aqueous phosphate medium at pH 8.0 by addition of 166 DyCl 3 to EDTMP at a molar ratio 1:1.75, with >99 % radiochemical purity, as determined by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). In vitro studies demonstrated that 166 Dy/ 166 Ho-EDTMP is unstable after dilution in saline but stable in human serum with no translocation of the daughter nucleus subsequent to β decay of 166 Dy, which could release free 166 Ho 3+ . Biodistribution in mice

Investigation of complexes with bone affinity using the In vivo generator system {sup 166} Dy/{sup 166} Ho; Investigacion de complejos con afinidad osea utilizando el Sistema de Generador in vivo {sup 166} Dy/{sup 166} Ho

Energy Technology Data Exchange (ETDEWEB)

Pedraza L, M

2006-07-01

The importance of this original research lies in the fact that it has proven that the [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP in vivo generator system is a stable complex that can be used as a therapeutic radiopharmaceutical. Multiple myeloma and other hematological malignancies have been treated by myeloablative radiotherapy/chemotherapy and subsequent stem cell transplantation. Bone-seeking radiopharmaceuticals such as {sup 166}Ho-DOTMP or {sup 153}Sm-DTMP, have been proposed for delivering ablative radiation doses to marrow in multiple myeloma and other hematological malignancies or have shown excellent results in palliative bone metastasis pain therapy, respectively. As lanthanides have similar chemical characteristics the phosphonate with bone affinity (EDTMP) labeled with Dy/Ho can be used for marrow ablation while causing minimal irradiation to normal organs. This in vivo generator system has not been previously reported. The aim of this research was to label EDTMP (ethylene diamine tetramethylene phosphonate) with {sup 166}Dy/{sup 166}Ho; to evaluate the in vitro and in vivo stability of both {sup 166}Dy-EDTMP and {sup 166}Ho-EDTMP complexes when the daughter {sup 166}Ho is formed as a dysprosium decay product; to determine the bone marrow cytotoxic and genotoxic effect in mice and to evaluate, by histopathology, the myeloablative potential of the [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP in vivo generator system. {sup 166}Dy was obtained by neutron irradiation of enriched {sup 164}Dy{sub 2}O{sub 3} in a TRIGA Mark III reactor. Labeling was carried out in an aqueous phosphate medium at pH 8.0 by addition of {sup 166}DyCl{sub 3} to EDTMP at a molar ratio 1:1.75, with >99 % radiochemical purity, as determined by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). In vitro studies demonstrated that {sup 166}Dy/{sup 166}Ho-EDTMP is unstable after dilution in saline but stable in human serum with no translocation of the daughter nucleus

Preparation of 166 Dy/166 Ho DTPA-bis biotin as a system of In vivo generator

International Nuclear Information System (INIS)

Jimenez V, M.R.

2003-01-01

The objective of this work was to synthesize the complex 166 Dy/ 166 Ho - diethylen triamine pentaacetic-bis Biotin ( 166 Dy/ 166 Ho DTPA-bis Biotin) to evaluate its potential as a new radiopharmaceutical in directed radiotherapy. The Dysprosium-166 was obtained for neutron irradiation of 164 Dy 2 0 3 in the TRIGA Mark III reactor. The labelled was carried out in aqueous solution to p H 8.0 for addition of 166 Dy Cl 3 to the diethylen triamine pentaacetic-α, ω-bis Biotin (DTPA-bis Biotin). The radiochemical purity was determined for HPLC and ITLC. The biological integrity of the marked biotin is evaluated by the biological recognition of the avidin for HPLC - molecular exclusion with and without avidin addition. The studies of stability in vitro were made in dilutions of saline solution to 0.9% and with human serum at 37 C incubated 1 and 24 hours. The complex 166 Dy/ 166 Ho DTPA-bis Biotin was obtained with a radiochemical purity of 99.1 ± 0.6%. The biological recognition of the complex 166 Dy/ 166 Ho DTPA-bis Biotin for the avidin it doesn't affect the labelling procedure. The studies in vitro demonstrated that the 166 Dy/ 166 Ho DTPA-bis Biotin is stable after the dilution in saline solution and in human serum that there is not translocation of the one radionuclide subsequent son to the beta decay of the 166 Dy that could produce the 166 Ho 3+ liberation. The studies of Biodistribution in healthy mice demonstrated that the one complex 166 Dy/ 166 Ho DTPA-bis Biotin have a high renal distribution. In conclusion the radiolabelled biotin in this investigation has the appropriate properties to be used as an In vivo generator system stable for directed radiotherapy. (Author)

Investigation of complexes with bone affinity using the In vivo generator system {sup 166} Dy/{sup 166} Ho; Investigacion de complejos con afinidad osea utilizando el Sistema de Generador in vivo {sup 166} Dy/{sup 166} Ho

Energy Technology Data Exchange (ETDEWEB)

Pedraza L, M

2006-07-01

The importance of this original research lies in the fact that it has proven that the [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP in vivo generator system is a stable complex that can be used as a therapeutic radiopharmaceutical. Multiple myeloma and other hematological malignancies have been treated by myeloablative radiotherapy/chemotherapy and subsequent stem cell transplantation. Bone-seeking radiopharmaceuticals such as {sup 166}Ho-DOTMP or {sup 153}Sm-DTMP, have been proposed for delivering ablative radiation doses to marrow in multiple myeloma and other hematological malignancies or have shown excellent results in palliative bone metastasis pain therapy, respectively. As lanthanides have similar chemical characteristics the phosphonate with bone affinity (EDTMP) labeled with Dy/Ho can be used for marrow ablation while causing minimal irradiation to normal organs. This in vivo generator system has not been previously reported. The aim of this research was to label EDTMP (ethylene diamine tetramethylene phosphonate) with {sup 166}Dy/{sup 166}Ho; to evaluate the in vitro and in vivo stability of both {sup 166}Dy-EDTMP and {sup 166}Ho-EDTMP complexes when the daughter {sup 166}Ho is formed as a dysprosium decay product; to determine the bone marrow cytotoxic and genotoxic effect in mice and to evaluate, by histopathology, the myeloablative potential of the [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP in vivo generator system. {sup 166}Dy was obtained by neutron irradiation of enriched {sup 164}Dy{sub 2}O{sub 3} in a TRIGA Mark III reactor. Labeling was carried out in an aqueous phosphate medium at pH 8.0 by addition of {sup 166}DyCl{sub 3} to EDTMP at a molar ratio 1:1.75, with >99 % radiochemical purity, as determined by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). In vitro studies demonstrated that {sup 166}Dy/{sup 166}Ho-EDTMP is unstable after dilution in saline but stable in human serum with no translocation of the daughter nucleus

Preparation of {sup 166} Dy/{sup 166} Ho DTPA-bis biotin as a system of In vivo generator; Preparacion de {sup 166} Dy/{sup 166} Ho DTPA-bis biotina como un sistema de generador In vivo

Energy Technology Data Exchange (ETDEWEB)

Jimenez V, M.R

2003-07-01

The objective of this work was to synthesize the complex {sup 166} Dy/{sup 166} Ho - diethylen triamine pentaacetic-bis Biotin ({sup 166} Dy/{sup 166} Ho DTPA-bis Biotin) to evaluate its potential as a new radiopharmaceutical in directed radiotherapy. The Dysprosium-166 was obtained for neutron irradiation of {sup 164} Dy{sub 2}0{sub 3} in the TRIGA Mark III reactor. The labelled was carried out in aqueous solution to p H 8.0 for addition of {sup 166} Dy Cl{sub 3} to the diethylen triamine pentaacetic-{alpha}, {omega}-bis Biotin (DTPA-bis Biotin). The radiochemical purity was determined for HPLC and ITLC. The biological integrity of the marked biotin is evaluated by the biological recognition of the avidin for HPLC - molecular exclusion with and without avidin addition. The studies of stability in vitro were made in dilutions of saline solution to 0.9% and with human serum at 37 C incubated 1 and 24 hours. The complex {sup 166} Dy/{sup 166} Ho DTPA-bis Biotin was obtained with a radiochemical purity of 99.1 {+-} 0.6%. The biological recognition of the complex {sup 166} Dy/{sup 166} Ho DTPA-bis Biotin for the avidin it doesn't affect the labelling procedure. The studies in vitro demonstrated that the {sup 166} Dy/{sup 166} Ho DTPA-bis Biotin is stable after the dilution in saline solution and in human serum that there is not translocation of the one radionuclide subsequent son to the beta decay of the {sup 166} Dy that could produce the {sup 166} Ho{sup 3+} liberation. The studies of Biodistribution in healthy mice demonstrated that the one complex {sup 166} Dy/{sup 166} Ho DTPA-bis Biotin have a high renal distribution. In conclusion the radiolabelled biotin in this investigation has the appropriate properties to be used as an In vivo generator system stable for directed radiotherapy. (Author)

Preparation of {sup 166} Dy/{sup 166} Ho DTPA-bis biotin as a system of In vivo generator; Preparacion de {sup 166} Dy/{sup 166} Ho DTPA-bis biotina como un sistema de generador In vivo

Energy Technology Data Exchange (ETDEWEB)

Jimenez V, M R

2003-07-01

The objective of this work was to synthesize the complex {sup 166} Dy/{sup 166} Ho - diethylen triamine pentaacetic-bis Biotin ({sup 166} Dy/{sup 166} Ho DTPA-bis Biotin) to evaluate its potential as a new radiopharmaceutical in directed radiotherapy. The Dysprosium-166 was obtained for neutron irradiation of {sup 164} Dy{sub 2}0{sub 3} in the TRIGA Mark III reactor. The labelled was carried out in aqueous solution to p H 8.0 for addition of {sup 166} Dy Cl{sub 3} to the diethylen triamine pentaacetic-{alpha}, {omega}-bis Biotin (DTPA-bis Biotin). The radiochemical purity was determined for HPLC and ITLC. The biological integrity of the marked biotin is evaluated by the biological recognition of the avidin for HPLC - molecular exclusion with and without avidin addition. The studies of stability in vitro were made in dilutions of saline solution to 0.9% and with human serum at 37 C incubated 1 and 24 hours. The complex {sup 166} Dy/{sup 166} Ho DTPA-bis Biotin was obtained with a radiochemical purity of 99.1 {+-} 0.6%. The biological recognition of the complex {sup 166} Dy/{sup 166} Ho DTPA-bis Biotin for the avidin it doesn't affect the labelling procedure. The studies in vitro demonstrated that the {sup 166} Dy/{sup 166} Ho DTPA-bis Biotin is stable after the dilution in saline solution and in human serum that there is not translocation of the one radionuclide subsequent son to the beta decay of the {sup 166} Dy that could produce the {sup 166} Ho{sup 3+} liberation. The studies of Biodistribution in healthy mice demonstrated that the one complex {sup 166} Dy/{sup 166} Ho DTPA-bis Biotin have a high renal distribution. In conclusion the radiolabelled biotin in this investigation has the appropriate properties to be used as an In vivo generator system stable for directed radiotherapy. (Author)

Study of magnetic properties of TGa6 with T = Ce, Pr, Nd, Tb, Ho, Dy and of solid solutions Ce(Ga1-x Alx)2

International Nuclear Information System (INIS)

Jerjini, M.

1987-10-01

At low temperature TGa 6 compounds are ordered with a Neel temperature of about 10 K. Magnetic structures are antiferromagnetic for T = Pr or Nd or modulated for T = Tb, Ho or Dy. Ce presents an abnormal behavior in CeGa 6 . Neutron inelastic scattering allows the determination of energy levels in the crystal field of cerium ion and evidences hybridation of 4f and valence electrons. Three magnetic transitions for T 6 . Study of CeGa 6 and solid solutions. Ce(Ga (1-x) Al x ) 2 shows that aluminium insertion reinforces the Kondo effect. For x = O.1 an incommensurable structure subsists at very low temperature. CeGa 2 is ordered with 3 magnetic structures. Magnetic moment is reduced with Al. The study of crystal field by neutron scattering shows that hybridation effects are more important for the compound with x = 0.1 [fr

Cytotoxic and genotoxic effect of the [166Dy]Dy/166Ho-EDTMP in vivo generator system in mice

International Nuclear Information System (INIS)

Pedraza-Lopez, Martha; Ferro-Flores, Guillermina; Arteaga de Murphy, Consuelo; Morales-Ramirez, Pedro; Piedras-Ross, Josefa; Murphy-Stack, Eduardo; Hernandez-Oviedo, Omar

2004-01-01

Multiple myeloma and other hematological malignancies have been treated by myeloablative radiotherapy/chemotherapy and subsequent stem cell transplantation. [ 166 Dy]Dy/ 166 Ho-ethylenediaminetetramethylene phosphonate (EDTMP) forms a stable in vivo generator system with selective skeletal uptake in mice; therefore, it could work as a potential and improved agent for marrow ablation. Induced bone marrow cytotoxicity and genotoxicity are determined by the reduction of reticulocytes (RET) and elevation of micronucleated reticulocyte (MN-RET) in peripheral blood and ablation by bone marrow histological studies. The aim of this study was to determine the bone marrow cytotoxic and genotoxic effect of the [ 166 Dy]Dy/ 166 Ho-EDTMP in vivo generator system in mice and to evaluate by histopathology its myeloablative potential. Enriched 166 Dy 2 O 3 was irradiated and [ 166 Dy]DyCl 3 was added to EDTMP in phosphate buffer (pH 8.0) in a molar ratio of 1:1.75. QC was determined by TLC. Dy-EDTMP complex was prepared the same way with nonirradiated dysprosium oxide. A group of BALB/c mice were intraperitoneally injected with the radiopharmaceutical and two groups of control animals were injected with the cold complex and with 0.9% sodium chloride, respectively. A blood sample was taken at the beginning of the experiments and every 48 h for 12 days postinjection. The animals were sacrificed, organs of interest taken out and the radioactivity determined. The femur was used for histological studies. Flow cytometry analysis was used to quantify the frequency of RET and MN-RET in the blood samples. The MCNP4B Monte Carlo computer code was used for dosimetry calculations. Radiochemical purity was 99% and the mean specific activity was 1.3 MBq/mg. The RET and MN-RET frequency were statistically different in the treatment at the end of the 12-day period demonstrating cytotoxicity and genotoxicity induced by the in vivo generator system. The histology studies show that there was

Therapeutical radiopharmaceuticals based In vivo generator system [166 Dy] Dy/166 Ho

International Nuclear Information System (INIS)

Ferro F, G.; Garcia S, L.; Monroy G, F.; Tendilla, J.I.; Pedraza L, M.; Murphy, C.A. de

2002-01-01

At the idea to administer to a patient a molecule containing in it structure a father radionuclide, with a half life enough large which allows to the radiolabelled molecule to take up position specifically in a white tissue and decaying In vivo to the daughter radionuclide with properties potentially therapeutic, it is known as In vivo generator system. In this work the preparation and the preliminary dosimetric valuations of radiopharmaceuticals based In vivo generator system 166 Dy Dy/ 166 Ho for applications in radioimmunotherapy, in the treatment of the rheumatoid arthritis and in the bone marrow ablation (m.o.) for candidates patients to bone marrow transplant are presented. (Author)

Genotoxic and cytotoxic damage by the therapeutic radiopharmaceutical [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP as in vivo generator system; Dano genotoxico y citotoxico por el radiofarmaco terpeutico [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP como sistema de generador in vivo

Energy Technology Data Exchange (ETDEWEB)

Pedraza L, M; Piedras R, J [Instituto Nacional de Ciencias Medicas y Nutricion, Salvador Zubiran. Vasco. de Quiroga 15, 14000 Mexico D.F. (Mexico); Ferro F, G; Morales R, P [ININ, Km. 36.5 Carretera Mexico-Toluca, Ocoyoacac, 52045 Estado de Mexico (Mexico); Murphy S, E [Hospital Santaelena, Mexico D.F. (Mexico); Hernandez O, O [Escuela Superior de Fisica y Matematicas, IPN, Mexico D.F. (Mexico)

2005-07-01

In patients with leukemias and multiple myeloma, the cure can be obtained to inclination of a bone marrow transplant (m.o.), for that which one is used a combination of external radiotherapy and chemotherapy with the consequent toxicity to healthy organs. The complex [{sup 166}Dy]Dy/{sup 166}Ho-ethylenediaminetetramethylenephosphonate ([{sup 166}Dy]Dy/{sup 166}Ho-EDTMP) it forms a generator system in vivo stable with bony selective likeness in mice therefore, this it could work as a therapeutic radiopharmaceutical for bone marrow ablation. The objective of this original work was to determine the genotoxic and cytotoxic damage produced by the [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP like a generator system in vivo by means of the reticulocytes reduction (RET) and micronucleus elevation in reticulocytes (RET-MN) in peripheral blood and to evaluate its myeloablative potential for histopathologic studies. It was irradiated {sup 166}Dy{sub 2}O{sub 3} enriched and it was add in form {sup 166}DyCI{sub 3} to the EDTMP in a softening media of phosphates (pH 8), the optimal molar relationship {sup 166}Dy: EDTMP was 1.7:1 and the radiochemical purity was evaluated by ITLC. The Dy:EDTMP complexes, non radioactive, its were prepared in the same way with non irradiated dysprosium oxide. A group of BALB/c mice was injected intraperitoneally with the radiopharmaceutical and two groups of control mice were injected with the non radioactive complex and with sodium chloride 0.9% respectively. Before injecting each one of the solutions it was take a basal sample of peripheral blood of the mouse tail and each 48 h post-injection during 12 d. The animals were sacrificed to obtain the organs of interest and to determine the radioactivity in each one. The femur was used for the histopathologic studies. The quantification of the frequency of RET and RET-MN was carried out by flow cytometry of the sanguine samples and the Monte Carlo code MCNP4B for the dosimetry calculations was used. The

Preparation of 166 Dy/166 Ho-Macro aggregates as an In vivo generator system for the treatment of arthrophaties

International Nuclear Information System (INIS)

Aldama A, T.K.

2003-01-01

The present work reports the obtention of macro aggregates of hydroxides of Dysprosium-166/Holmium-166 ( 166 Dy/ 166 Ho-MH), as a generator system in vivo to be used in the treatment of arthritis rheumatoid. The 166 Dy was obtained by neutron irradiation of 166 DyO 3 (enriched to 98.45%) by 20 h in the TRIGA Mark III Reactor and 50 h of decay, to the oxide of 166 Dy/ 166 Ho formed, it was added HCl 0.12 N to obtain a final volume of 3.5 ml of solution of 166 Dy/ 166 Ho chloride. The solution of 166D yCl 3 solution was obtained with an activity of 3.502 mCi (129 MBq), appropriate for the preparation of the radiopharmaceutical 166 Dy/ 166 Ho-MH. The separation of the 166 Dy from the 166 Ho, was carried out by chromatography in an cation exchange column, gaining an appropriate separation, obtaining a 166 Dy with a radionuclide purity greater than 90%. The 166 Dy/ 166 Ho-MH were prepared by addition to the solution of 166 DyCI 3 NaOH 0.5 N low ultrasonic bath with later centrifugation, decanted and resuspension in saline solution, obtaining a radiopharmaceutical with a generator system 166 Dy/ 166 Ho with particles of size average of 3 μm, in form of 166 Dy / 166 Ho-MH. Under these conditions, it was obtained a radiochemical yield greater than 99%. The microscopic analysis and of filtration showed that the formulation doesn't present particles smaller than to 1 μm, neither greater to 50 μm, which will allow, the quick phagocytosis for the synoviocytes of the synovial membrane, and by consequence, an homogeneous distribution of the radiation dose could exist. The sedimentation velocity for the formulated suspension is of 0.04 cm/min that it will allow the administration of homogeneous activities of the radiopharmaceutical, to the no deposit in the injection devices. The studies of stability in vitro indicate us that inside the articulation, the particles won't probably reduce its size neither their radiochemical purity, for that the flight extra articular will be

Genotoxic and cytotoxic damage by the therapeutic radiopharmaceutical [166Dy]Dy/166Ho-EDTMP as in vivo generator system

International Nuclear Information System (INIS)

Pedraza L, M.; Piedras R, J.; Ferro F, G.; Morales R, P.; Murphy S, E.; Hernandez O, O.

2005-01-01

In patients with leukemias and multiple myeloma, the cure can be obtained to inclination of a bone marrow transplant (m.o.), for that which one is used a combination of external radiotherapy and chemotherapy with the consequent toxicity to healthy organs. The complex [ 166 Dy]Dy/ 166 Ho-ethylenediaminetetramethylenephosphonate ([ 166 Dy]Dy/ 166 Ho-EDTMP) it forms a generator system in vivo stable with bony selective likeness in mice therefore, this it could work as a therapeutic radiopharmaceutical for bone marrow ablation. The objective of this original work was to determine the genotoxic and cytotoxic damage produced by the [ 166 Dy]Dy/ 166 Ho-EDTMP like a generator system in vivo by means of the reticulocytes reduction (RET) and micronucleus elevation in reticulocytes (RET-MN) in peripheral blood and to evaluate its myeloablative potential for histopathologic studies. It was irradiated 166 Dy 2 O 3 enriched and it was add in form 166 DyCI 3 to the EDTMP in a softening media of phosphates (pH 8), the optimal molar relationship 166 Dy: EDTMP was 1.7:1 and the radiochemical purity was evaluated by ITLC. The Dy:EDTMP complexes, non radioactive, its were prepared in the same way with non irradiated dysprosium oxide. A group of BALB/c mice was injected intraperitoneally with the radiopharmaceutical and two groups of control mice were injected with the non radioactive complex and with sodium chloride 0.9% respectively. Before injecting each one of the solutions it was take a basal sample of peripheral blood of the mouse tail and each 48 h post-injection during 12 d. The animals were sacrificed to obtain the organs of interest and to determine the radioactivity in each one. The femur was used for the histopathologic studies. The quantification of the frequency of RET and RET-MN was carried out by flow cytometry of the sanguine samples and the Monte Carlo code MCNP4B for the dosimetry calculations was used. The radiochemical purity was 99% and in average the specific

Magnetic Properties of Dy in Pb2Sr2DyCu3O8

International Nuclear Information System (INIS)

Skanthakumar, S.; Soderholm, L.; Movshovich, R.

1999-01-01

Superconductivity can be induced at high temperatures in Pb 2 Sr 2 RCu 3 O 8 (R - rare earth) by partially doping Ca 2+ for R 3+ . In order to understand the interplay between magnetism and superconductivity, the magnetic properties of the parent compounds, Pb 2 Sr 2 RCu 3 O 8 , have been studied. The work presented here includes magnetic susceptibility and specific heat measurements on R=Dy and extends the previous studies on R=Ce, Pr, Tb, Ho and Er. Specific heat experiments suggest that the Dy ions order antiferromagnetically with an ordering temperature of 1.3K. The magnetic susceptibility data are in good agreement with the susceptibility calculated using crystal field parameters that are extrapolated from previous modeling of the R=Er and Ho analogs of this series

Preparation of {sup 166} Dy/{sup 166} Ho-Macro aggregates as an In vivo generator system for the treatment of arthrophaties; Preparacion de {sup 166} Dy/{sup 166} Ho-Macro agregados como un sistema de generador In vivo para el tratamiento de artropatias

Energy Technology Data Exchange (ETDEWEB)

Aldama A, T.K

2003-07-01

The present work reports the obtention of macro aggregates of hydroxides of Dysprosium-166/Holmium-166 ({sup 166} Dy/{sup 166} Ho-MH), as a generator system in vivo to be used in the treatment of arthritis rheumatoid. The {sup 166} Dy was obtained by neutron irradiation of {sup 166} DyO{sub 3} (enriched to 98.45%) by 20 h in the TRIGA Mark III Reactor and 50 h of decay, to the oxide of {sup 166} Dy/{sup 166} Ho formed, it was added HCl 0.12 N to obtain a final volume of 3.5 ml of solution of {sup 166} Dy/{sup 166} Ho chloride. The solution of {sup 166D}yCl{sub 3} solution was obtained with an activity of 3.502 mCi (129 MBq), appropriate for the preparation of the radiopharmaceutical {sup 166} Dy/{sup 166} Ho-MH. The separation of the {sup 166} Dy from the {sup 166} Ho, was carried out by chromatography in an cation exchange column, gaining an appropriate separation, obtaining a {sup 166} Dy with a radionuclide purity greater than 90%. The {sup 166} Dy/{sup 166} Ho-MH were prepared by addition to the solution of {sup 166} DyCI{sub 3} NaOH 0.5 N low ultrasonic bath with later centrifugation, decanted and resuspension in saline solution, obtaining a radiopharmaceutical with a generator system {sup 166} Dy/ {sup 166} Ho with particles of size average of 3 {mu}m, in form of {sup 166} Dy / {sup 166} Ho-MH. Under these conditions, it was obtained a radiochemical yield greater than 99%. The microscopic analysis and of filtration showed that the formulation doesn't present particles smaller than to 1 {mu}m, neither greater to 50 {mu}m, which will allow, the quick phagocytosis for the synoviocytes of the synovial membrane, and by consequence, an homogeneous distribution of the radiation dose could exist. The sedimentation velocity for the formulated suspension is of 0.04 cm/min that it will allow the administration of homogeneous activities of the radiopharmaceutical, to the no deposit in the injection devices. The studies of stability in vitro indicate us that inside

Preparation of {sup 166} Dy/{sup 166} Ho-Macro aggregates as an In vivo generator system for the treatment of arthrophaties; Preparacion de {sup 166} Dy/{sup 166} Ho-Macro agregados como un sistema de generador In vivo para el tratamiento de artropatias

Energy Technology Data Exchange (ETDEWEB)

Aldama A, T K

2003-07-01

The present work reports the obtention of macro aggregates of hydroxides of Dysprosium-166/Holmium-166 ({sup 166} Dy/{sup 166} Ho-MH), as a generator system in vivo to be used in the treatment of arthritis rheumatoid. The {sup 166} Dy was obtained by neutron irradiation of {sup 166} DyO{sub 3} (enriched to 98.45%) by 20 h in the TRIGA Mark III Reactor and 50 h of decay, to the oxide of {sup 166} Dy/{sup 166} Ho formed, it was added HCl 0.12 N to obtain a final volume of 3.5 ml of solution of {sup 166} Dy/{sup 166} Ho chloride. The solution of {sup 166D}yCl{sub 3} solution was obtained with an activity of 3.502 mCi (129 MBq), appropriate for the preparation of the radiopharmaceutical {sup 166} Dy/{sup 166} Ho-MH. The separation of the {sup 166} Dy from the {sup 166} Ho, was carried out by chromatography in an cation exchange column, gaining an appropriate separation, obtaining a {sup 166} Dy with a radionuclide purity greater than 90%. The {sup 166} Dy/{sup 166} Ho-MH were prepared by addition to the solution of {sup 166} DyCI{sub 3} NaOH 0.5 N low ultrasonic bath with later centrifugation, decanted and resuspension in saline solution, obtaining a radiopharmaceutical with a generator system {sup 166} Dy/ {sup 166} Ho with particles of size average of 3 {mu}m, in form of {sup 166} Dy / {sup 166} Ho-MH. Under these conditions, it was obtained a radiochemical yield greater than 99%. The microscopic analysis and of filtration showed that the formulation doesn't present particles smaller than to 1 {mu}m, neither greater to 50 {mu}m, which will allow, the quick phagocytosis for the synoviocytes of the synovial membrane, and by consequence, an homogeneous distribution of the radiation dose could exist. The sedimentation velocity for the formulated suspension is of 0.04 cm/min that it will allow the administration of homogeneous activities of the radiopharmaceutical, to the no deposit in the injection devices. The studies of stability in vitro indicate us that inside the

Dy163-Ho163 branching: an s-process barometer

International Nuclear Information System (INIS)

Beer, H.; Walter, G.; Macklin, R.L.

1984-01-01

The neutron capture cross sections of Dy163 and Er164 have been measured to analyze the s-process branching at Dy163-Ho163. The reproduction of the s-process abundance of Er164 via this branching is sensitive to temperature kT, neutron density, and electron density n/sub e/. The calculations using information from other branchings on kT and the neutron density n/sub n/ give constraints for n/sub e/ at the site of the s-process

Down-shifting by energy transfer in Tb{sup 3+}/Dy{sup 3+} co-doped zinc phosphate glasses

Energy Technology Data Exchange (ETDEWEB)

Caldiño, U., E-mail: cald@xanum.uam.mx [Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, P.O. Box 55-534, México, D.F. 09340 (Mexico); Muñoz H, G.; Camarillo, I. [Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, P.O. Box 55-534, México, D.F. 09340 (Mexico); Speghini, A. [Dipartimento di Biotecnologie, Università 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, Università di Verona, and INSTM, UdR Verona, Strada Le Grazie 15, I-37314 Verona (Italy)

2015-05-15

An optical spectroscopy investigation of zinc phosphate glasses activated with Tb{sup 3+}/Dy{sup 3+} ions is carried out through photoluminescence spectra and decay time measurements. The emission color can be adjusted from yellow–green light, with CIE1931 chromaticity coordinates (0.36,0.44), toward the white light region (0.35,0.39) by decreasing the Tb{sup 3+} content from 1.0 to 0.1 mol% of Tb(PO{sub 3}){sub 3} upon Dy{sup 3+} excitation at 423 nm. Such visible region luminescence is generated by {sup 5}D{sub 4}→{sup 7}F{sub 5} and {sup 5}D{sub 4}→{sup 7}F{sub 3} emissions of Tb{sup 3+} in addition to {sup 4}I{sub 15/2}→{sup 6}H{sub 15/2}, {sup 4}F{sub 9/2}→{sup 6}H{sub 15/2}, {sup 4}F{sub 9/2}→{sup 6}H{sub 13/2} and {sup 4}F{sub 9/2}→{sup 6}H{sub 11/2} emissions of Dy{sup 3+}, so that Tb{sup 3+} emission is sensitized by Dy{sup 3+} through a non-radiative resonant energy transfer. A dominant {sup 5}D{sub 4}→{sup 7}F{sub 5} green emission is observed in detriment of the {sup 5}D{sub 3}→{sup 7}F{sub J} blue emissions upon 282 nm excitation, as well as an extended excitation range (280–500 nm), due to multiple Dy{sup 3+} and Tb{sup 3+} transitions, which might contribute to enhance the spectral response of solar photovoltaic cells by down-shifting of the incident solar spectrum. - Highlights: • Zn(PO{sub 3}){sub 2} glasses are optically activated with Tb{sup 3+}/Dy{sup 3+} (ZPTbDy). • Non-radiative resonant energy transfer takes place between Tb{sup 3+} and Dy{sup 3+}. • Luminescence can be adjusted from yellow–green light toward the white light region. • ZPTbDy phosphor exhibits spectroscopic properties for photovoltaic applications.

Therapeutical radiopharmaceuticals based In vivo generator system [{sup 166} Dy] Dy/{sup 166} Ho; Radiofarmacos terapeuticos basados en un sistema de generador In vivo [{sup 166}Dy] Dy/{sup 166}Ho

Energy Technology Data Exchange (ETDEWEB)

Ferro F, G.; Garcia S, L.; Monroy G, F.; Tendilla, J.I. [Gerencia de Aplicaciones Nucleares en la Salud, ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Pedraza L, M.; Murphy, C.A. de [Departamento de Medicina Nuclear, Instituto Nacional de Pediatria, Mexico D.F. (Mexico)

2002-07-01

At the idea to administer to a patient a molecule containing in it structure a father radionuclide, with a half life enough large which allows to the radiolabelled molecule to take up position specifically in a white tissue and decaying In vivo to the daughter radionuclide with properties potentially therapeutic, it is known as In vivo generator system. In this work the preparation and the preliminary dosimetric valuations of radiopharmaceuticals based In vivo generator system {sup 166} Dy Dy/{sup 166} Ho for applications in radioimmunotherapy, in the treatment of the rheumatoid arthritis and in the bone marrow ablation (m.o.) for candidates patients to bone marrow transplant are presented. (Author)

Optical absorption, luminescence, and energy transfer processes studies for Dy3+/Tb3+-codoped borate glasses for solid-state lighting applications

Science.gov (United States)

Lakshminarayana, G.; Kaky, Kawa M.; Baki, S. O.; Lira, A.; Caldiño, U.; Kityk, I. V.; Mahdi, M. A.

2017-10-01

By using melt quenching technique, good optical quality singly doped Dy3+ or Tb3+ and Dy3+/Tb3+-codoped borate glasses were synthesized and studied by optical absorption, excitation, emission and decay lifetimes curve analysis. Following the absorption spectrum, the evaluated Judd-Ofelt (J-O) intensity parameters (Ωλ (λ = 2, 4 and 6)) were used to calculate the transition probability (AR), the branching ratio (βR), and the radiative lifetime (τR) for different luminescent transitions such as 4I15/2 → 6H15/2, 4F9/2 → 6H15/2, 4F9/2 → 6H13/2, 4F9/2 → 6H11/2 and 4F9/2 → 6H9/2,6F11/2 for the 0.5 mol % singly Dy3+-doped glass. The βR calculated (65%) indicates that for lasing applications, 4F9/2 → 6H13/2 emission transition is highly suitable. For all the Dy3+/Tb3+-codoped glasses, Tb3+: 5D3→7F6 emission decay lifetime curves are found to be non-exponential in nature for different concentrations of Dy3+ codoping. Using the Inokuti-Hirayama model, these nonexponential decay curves were analyzed to identify the nature of the energy transfer (ET) processes and here the electric dipole-dipole interaction is dominant for the ET. Based on the excitation and emission spectra and decay lifetimes curve analysis, the cross relaxation and ET processes between Dy3+ and Tb3+ were confirmed. For the 0.5 mol % Tb3+ and 2.0 mol % Dy3+-codoped glass, the evaluated Tb3+→Dy3+ ET efficiency (η) is found to be 45% under 369 nm excitation. Further, for Tb3+/Dy3+ -codoped glasses, an enhancement of Tb3+ green emission is observed up to 1.5 mol % Dy3+ codoping, and this is due to the non-radiative resonant ET from Dy3+ to Tb3+ upon 395 nm excitation. For singly 0.5 mol % Dy3+ or 0.5 mol % Tb3+-doped glass, the calculated color coordinates (x,y) and correlated color temperatures (CCT) represent the neutral white or warm white light regions, whereas Dy3+/Tb3+-codoped glasses (x,y) and CCT values fall in the yellowish green region with respect to the different Dy3

CeNi{sub 3}-type rare earth compounds: crystal structure of R{sub 3}Co{sub 7}Al{sub 2} (R=Y, Gd–Tm) and magnetic properties of {Gd–Er}{sub 3}Co{sub 7}Al{sub 2}, {Tb, Dy}{sub 3}Ni{sub 8}Si and Dy{sub 3}Co{sub 7.68}Si{sub 1.32}

Energy Technology Data Exchange (ETDEWEB)

Morozkin, A.V., E-mail: morozkin@tech.chem.msu.ru [Department of Chemistry, Moscow State University, Leninskie Gory, House 1, Building 3, GSP-1, Moscow 119991 (Russian Federation); Yapaskurt, V.O. [Department of Petrology, Geological Faculty Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation); Nirmala, R. [Indian Institute of Technology Madras, Chennai 600 036 (India); Quezado, S.; Malik, S.K. [Departamento de Física Teórica e Experimental, Universidade Federal do Rio Grande do Norte, Natal 59082-970 (Brazil)

2017-03-15

The crystal structure of new CeNi{sub 3}-type {Y, Gd–Tm}{sub 3}Co{sub 7}Al{sub 2} (P63/mmc. N 194, hP24) compounds has been established using powder X-ray diffraction studies. The magnetism of Tb{sub 3}Ni{sub 8}Si and Dy{sub 3}Ni{sub 8}Si is dominated by rare earth sublattice and the magnetic properties of R{sub 3}Co{sub 7}Al{sub 2} (R =Gd–Er) and Dy{sub 3}Co{sub 7.68}Si{sub 1.32} are determined by both rare earth and cobalt sublattices. Magnetization data indicate ferromagnetic ordering of {Tb, Dy}{sub 3}Ni{sub 8}Si at 32 K and 21 K, respectively. Gd{sub 3}Co{sub 7}Al{sub 2} and Tb{sub 3}Co{sub 7}Al{sub 2} exhibit ferromagnetic ordering at 309 K and 209 K, respectively, whereas Dy{sub 3}Co{sub 7}Al{sub 2}, Ho{sub 3}Co{sub 7}Al{sub 2}, Er{sub 3}Co{sub 7}Al{sub 2} and Dy{sub 3}Co{sub 7.68}Si{sub 1.32} show a field dependent ferromagnetic-like ordering at 166 K, 124 K, 84 K and 226 K, respectively followed by a low temperature transition at 34 K for Dy{sub 3}Co{sub 7}Al{sub 2}, 18 K for Ho{sub 3}Co{sub 7}Al{sub 2}, 56 K for Er{sub 3}Co{sub 7}Al{sub 2}, 155 K and 42 K for Dy{sub 3}Co{sub 7.68}Si{sub 1.32}. Among these compounds, Dy{sub 3}Ni{sub 8}Si shows largest magnetocaloric effect (isothermal magnetic entropy change) of −11.6 J/kg·K at 18 K in field change of 50 kOe, whereas Tb{sub 3}Co{sub 7}Al{sub 2}, Dy{sub 3}Co{sub 7}Al{sub 2} and Dy{sub 3}Co{sub 7.68}Si{sub 1.32} exhibit best permanent magnet properties in the temperature range of 2–5 K with remanent magnetization of 11.95 μ{sub B}/fu, 12.86 μ{sub B}/fu and 14.4 μ{sub B}/fu, respectively and coercive field of 3.0 kOe, 1.9 kOe and 4.4 kOe, respectively. - Highlights: • {Y, Gd–Tm}{sub 3}Co{sub 7}Al{sub 2} compounds crystallize in the CeNi{sub 3}-type structure. • {Gd-Er}{sub 3}Co{sub 7}Al{sub 2} show ferrimagnetic ordering at 309 K, 209 K, 166 K, 124 K and 84 K. • Dy{sub 3}Co{sub 7.68}Si{sub 1.32} exhibits magnetic transitions at 226 K, 155 K and 42 K. • {Tb-Er}{sub 3}Co{sub 7}Al{sub 2

Determination of the cross section for (n,p) and (n,α) reactions on 165Ho at 13.5 and 14.8 MeV

International Nuclear Information System (INIS)

Luo, Junhua; An, Li; Jiang, Li; He, Long

2015-01-01

Activation cross-sections for the 165 Ho(n,p) 165 Dy and 165 Ho(n,α) 162 Tb reactions were measured by means of the activation method at 13.5 and 14.8 MeV, to resolve inconsistencies in existing data. A neutron beam produced via the 3 H(d,n) 4 He reaction was used. Statistical model calculations were performed using the nuclear-reaction codes EMPIRE-3.2 Malta and TALYS-1.6 with default parameters, at neutron energies varying from the reaction threshold to 20 MeV. Results are also discussed and compared with some corresponding values found in the literature. The calculational results on the 165 Ho(n,α) 162 Tb reaction agreed fairly well with experimental data, but there were large discrepancies in the results for the 165 Ho(n,p) 165 Dy reaction. - Highlights: • 27 Al(n,α) 24 Na was used as a monitor for neutron fleunce. • The cross sections for the 165 Ho(n,p) 165 Dy and 165 Ho(n,α) 162 Tb reactions were measured at 13.5 and 14.8 MeV neutron energies. • Nuclear reaction codes TALYS-1.6 and EMPIRE-3.2 Malta were used to model the reactions. • Inconsistency with previous data and with model calculations are noted

Cytotoxic and genotoxic effect of the [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP in vivo generator system in mice

Energy Technology Data Exchange (ETDEWEB)

Pedraza-Lopez, Martha [Departamento de Medicina Nuclear, Instituto Nacional de Ciencias Medicas y Nutricion, Salvador Zubiran, Delegacion Tlalpan, Mexico DF 14000 (Mexico); Ferro-Flores, Guillermina [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca, Ocoyoacac, Estado de Mexico, CP 52045 (Mexico); Arteaga de Murphy, Consuelo [Departamento de Medicina Nuclear, Instituto Nacional de Ciencias Medicas y Nutricion, Salvador Zubiran, Delegacion Tlalpan, Mexico DF 14000 (Mexico)]. E-mail: consuelo_murphy@yahoo.com.mx; Morales-Ramirez, Pedro [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca, Ocoyoacac, Estado de Mexico, CP 52045 (Mexico); Piedras-Ross, Josefa [Departamento de Medicina Nuclear, Instituto Nacional de Ciencias Medicas y Nutricion, Salvador Zubiran, Delegacion Tlalpan, Mexico DF 14000 (Mexico); Murphy-Stack, Eduardo [Hospital Santaelena, Mexico DF (Mexico); Hernandez-Oviedo, Omar [Escuela Superior de Fisica y Matematicas, IPN, Mexico DF (Mexico)

2004-11-01

Multiple myeloma and other hematological malignancies have been treated by myeloablative radiotherapy/chemotherapy and subsequent stem cell transplantation. [{sup 166}Dy]Dy/{sup 166}Ho-ethylenediaminetetramethylene phosphonate (EDTMP) forms a stable in vivo generator system with selective skeletal uptake in mice; therefore, it could work as a potential and improved agent for marrow ablation. Induced bone marrow cytotoxicity and genotoxicity are determined by the reduction of reticulocytes (RET) and elevation of micronucleated reticulocyte (MN-RET) in peripheral blood and ablation by bone marrow histological studies. The aim of this study was to determine the bone marrow cytotoxic and genotoxic effect of the [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP in vivo generator system in mice and to evaluate by histopathology its myeloablative potential. Enriched {sup 166}Dy{sub 2}O{sub 3} was irradiated and [{sup 166}Dy]DyCl{sub 3} was added to EDTMP in phosphate buffer (pH 8.0) in a molar ratio of 1:1.75. QC was determined by TLC. Dy-EDTMP complex was prepared the same way with nonirradiated dysprosium oxide. A group of BALB/c mice were intraperitoneally injected with the radiopharmaceutical and two groups of control animals were injected with the cold complex and with 0.9% sodium chloride, respectively. A blood sample was taken at the beginning of the experiments and every 48 h for 12 days postinjection. The animals were sacrificed, organs of interest taken out and the radioactivity determined. The femur was used for histological studies. Flow cytometry analysis was used to quantify the frequency of RET and MN-RET in the blood samples. The MCNP4B Monte Carlo computer code was used for dosimetry calculations. Radiochemical purity was 99% and the mean specific activity was 1.3 MBq/mg. The RET and MN-RET frequency were statistically different in the treatment at the end of the 12-day period demonstrating cytotoxicity and genotoxicity induced by the in vivo generator system. The

Complex magnetic properties and large magnetocaloric effects in RCoGe (R=Tb, Dy compounds

Directory of Open Access Journals (Sweden)

Yan Zhang

2018-05-01

Full Text Available Complicated magnetic phase transitions and Large magnetocaloric effects (MCEs in RCoGe (R=Tb, Dy compounds have been reported in this paper. Results show that the TbCoGe compounds have a magnetic phase transition from antiferromagnetic to paramagnetic (AFM-PM at TN∼16 K, which is close to the value reported by neutron diffraction. The DyCoGe compound undergoes complicated phase changes from 2 K up to 300 K. The peak at 10 K displays a phase transition from antiferromagnetic to ferromagnetic (AFM-FM. In particular, a significant ferromagnetic to paramagnetic (FM-PM phase transition was found at the temperature as high as 175 K and the cusp becomes more abrupt with the magnetic field increasing from 0.01 T to 0.1 T. The maximum value of magnetic entropy change of TbCoGe and DyCoGe compounds achieve 14.5 J/kg K and 11.5 J/kg K respectively for a field change of 0-5 T. Additionally, the correspondingly considerable refrigerant capacity value of 260 J/kg and 242 J/kg are also obtained respectively, suggesting that both TbCoGe and DyCoGe compounds could be considered as good candidates for low temperature magnetic refrigerant.

The effects of boron on Tb0.27Dy0.73Fe2 compound

International Nuclear Information System (INIS)

Wu Lei; Chen Xicheng; Chen Xishen

1995-01-01

The magnetostrictive properties and microstructure of Tb 0.27 Dy 0.73 Fe 2 B x (x=0, 0.05, 0.1, 0.15, 0.2) have been investigated. Measurement of magnetic properties, X-ray diffraction and magnetostriction were made on Tb 0.27 Dy 0.73 Fe 2 B x polycrystalline samples prepared by arc melting. With the increase of boron content x, the iron-rich phase which leads to the detriment of magnetostrictive properties, decreases. The matrix phase of these alloys also has the MgCu 2 structure. The lattice constant and Curie transition temperature change only slightly. The doping of boron in the Tb 0.27 Dy 0.73 Fe 2 alloy can restrain the emergence of the iron-rich phase. The peritectic region probably shifts slightly with the addition of boron. ((orig.))

HoTbTi2O7, the mixtures of spin ice and spin liquid

International Nuclear Information System (INIS)

Chang, L.J.; Terashita, H.; Schweika, W.; Chen, Y.Y.; Gardner, J.S.

2007-01-01

Polycrystalline samples of Ho 2- x Tb x Ti 2 O 7 (x=0.5, 1, and 1.5) have been prepared and characterized. No long-range order is observed for HoTbTi 2 O 7 in magnetization and specific heat measurements down to 2 K. The low-energy magnetic excitation measurements suggests that HoTbTi 2 O 7 possesses both characteristics of spin ice and spin liquid in the ground state

Phase composition of iron-rich R-Fe-Si (R=Dy, Ho, Er) alloys

International Nuclear Information System (INIS)

Ivanova, G.V.; Makarova, G.M.; Shcherbakova, E.V.; Belozerov, E.V.

2005-01-01

Phase composition is studied in iron-rich alloys of R-Fe-Si (R=Dy, Ho, Er). In the as-cast state R 2 (Fe, Si) 17 of type Th 2 Ni 17 and R(Fe, Si) 12 compounds are observed; in the alloys of rated composition of R(Fe 0.85 Si 0.15 ) 8.5 (R=Dy, Er) a compound R 2 (Fe, Si) 17 of Th 2 Zn 17 -type is revealed as well. The annealing at 1273 K results in formation of Dy 3 (Fe, Si) 29 and also the compounds with the presumed composition of Dy 4 (Fe, Si) 41 and Ho 4 (Fe, Si) 41 . As this takes place the alloys contain a transition structure as well that represents a set of small-sized areas with various type short-range order in mutual displacement of Fe-Fe(Si) dumpbell chains. The process of phase formation at 1273 K is faced with difficulties. Even the annealing for 1000 h does not result in the state of equilibrium [ru

Labeling of biotin with Dy-166/Ho-166 as a stable in vivo generator system

International Nuclear Information System (INIS)

Ferro-Flores, G.; Monroy-Guzman, F.; Jimenez-Varela, R.; Tendilla, J.I.; Arteaga-Murphy, C.; Pedraza-Lopez, M.

2002-01-01

Aim: Biotin is a vitamin found in low concentration in blood and tissue. In radioimmunodiagnosis and radioimmunotherapy practice, the pre-targeting avidin-biotin strategy has shown that target-to-nontarget radioactivity ratios can be significantly improved. In addition, the biotin content of cancerous tumors is higher than that of normal tissue and it has been found in the cellular nucleus due to a specific transfer of biotin to histones by human serum biotinidase. Because of its nuclear properties, the 166 Dy/ 166 Ho radionuclide pair can be considered as an in vivo generator system. The aim of this work was to synthesize 166 Dy/ 166 Ho-DTPA-bisBiotin to evaluate its potential as a new radiopharmaceutical for targeted radiotherapy. Material and Methods: Dysprosium-166/Holmium-166 chloride was obtained by neutron irradiation of 50 mg of 99% enriched 164 Dy 2 O 3 in a TRIGA Mark III reactor at a flux in the central thimble of 3.10 13 n. cm -2 s -1 for 20 h. Following irradiation, the target was allowed to decay for 2 days, 100 μL of 12 N chloride acid were added and the mixture stirred for 3 min. To this suspension 1.0 mL of injectable water were added and heated for 2 min at 90 0 C. The biotin used in this investigation was diethylenetriaminepentaacetic-α,ω-bis(biocytinamide)(DTPA-bisBiotin, Sigma). Sterile and apyrogenic V-vial was prepared to contain 16.0 mg (1.52 x 10 -4 mmol) of the DTPA-bisBiotin in 4.0 mL of 0.05 M bicarbonate buffer (pH 8.5), then 50 μL of the radiochloride solution were added to the preparation. TLC aluminum cellulose sheets were used as the stationary phase and a ternary mixture of methanol: water: ammonium hydroxide (20:40:2) as the mobile phase. 166 Dy/ 166 Ho-DTPA-bisBiotin traveled with the solvent front R f 0.9-1.0 and the Dy +3 /Ho +3 species remained at the origin (R f 0.0). HPLC reverse phase was also used to evaluate radiochemical purity. The biological integrity of labeled biotin was achieved evaluating its avidity for avidin

Labeling of biotin with 166Dy/166Ho as a stable in vivo generator system

International Nuclear Information System (INIS)

Ferro-Flores, G.; Monroy-Guzman, F.; Tendilla, J.I.; Garcia-Salinas, L.; Villarreal-Barajas, J.E.; Arteaga-Murphy, C.

2002-01-01

Biotin (cis-tetrahydro-2-oxothieno[3,4-d]imidazoline-4-valeric acid) is a 244 Da vitamin found in low concentration in blood and tissue (vitamin H). The aim of this work was to synthesize 166 Dy/ 166 Ho-DTPA-bisBiotin to evaluate its potential as a new radiopharmaceutical for targeted radiotherapy. Dysprosium-166/ holmium-166 chloride was obtained by neutron irradiation of 20 mg of enriched Dy 2 O 3 ( 164 Dy, 99 %, from Oak Ridge NL) in a Triga Mark III reactor at a flux in the central thimble of 3.10 13 n. cm -2 s -1 for 20 h. Following irradiation, the target was allowed to decay for 2 days, then 100 μL of 12 N chloride acid were added and stirred for 1 min. To this solution was added 500 μL of injectable water and the whole was also stirred for 2 min. The average radioactive concentration was 332 MBq/ml. The biotin used in this investigation was covalently conjugated to diethylenetriamine pentaacetic acid (DTPA) through the use of the cyclic anhydride and lysine conjugate to biotin (biocytin) to produce DTPA-α,ω-bis(biocytin amide)(DTPA-bisBiotin). Sterile and apyrogenic V-vial was prepared to contain 2.0 mg (1.9 x 10 -3 mmol) of the DTPA-bisbiotin compound in 1.0 ml of 0.05 M bicarbonate buffer (pH 8.0) and then 20 μL of 166 Dy2Cl3 solution were added to the preparation. Thin Layer Chromatography aluminum cellulose sheets were utilised as the stationary phase and a ternary mixture of methanol:water:ammonium hydroxide (20:40:2) as the mobile phase. 166 Dy/ 166 Ho-DTPA-bisBiotin travelled with the solvent front R f 0.9-1.0 and the Dy +3 /Ho +3 species remained at the origin (R f = 0). The biological integrity of labelled biotin was achieved evaluating its avidity for avidin in an agarose column. Stability studies against dilution were carried out by diluting the radiocomplex solution with saline and with human serum at 310 K. After 10 min and 24 h the radiochemical purity of each 166 Dy/ 166 Ho complex solution was determined by TLC. The complex 166 Dy/ 166

Hetero-metallic {3d-4f-5d} complexes: preparation and magnetic behavior of trinuclear [(L(Me2)Ni-Ln){W(CN)(8)}] compounds (Ln = Gd, Tb, Dy, Ho, Er, Y; L(Me2) = Schiff base) and variable SMM characteristics for the Tb derivative.

Science.gov (United States)

Sutter, Jean-Pascal; Dhers, Sébastien; Rajamani, Raghunathan; Ramasesha, S; Costes, Jean-Pierre; Duhayon, Carine; Vendier, Laure

2009-07-06

Assembling bimetallic {Ni-Ln}(3+) units and {W(CN)(8)}(3-) is shown to be an efficient route toward heteronuclear {3d-4f-5d} compounds. The reaction of either the binuclear [{L(Me2)Ni(H(2)O)(2)}{Ln(NO(3))(3)}] complexes or their mononuclear components [L(Me2)Ni] and Ln(NO(3))(3) with (HNBu(3))(3){W(CN)(8)} in dmf followed by diffusion of tetrahydrofuran yielded the trinuclear [{L(Me2)NiLn}{W(CN)(8)}] compounds 1 (Ln = Y), 2a,b (Gd), 3a,b (Tb), 4 (Dy), 5 (Ho), and 6 (Er) as crystalline materials. All of the derivatives possess the trinuclear core resulting from the linkage of the {W(CN)(8)} to the Ni center of the {Ni-Ln} unit. Differences are found in the solvent molecules acting as ligands and/or in the lattice depending on the crystallization conditions. For all the compounds ferromagnetic {Ni-W} and {Ni-Ln} (Ln = Gd, Tb, Dy, and Er} interactions are operative resulting in high spin ground states. Parameterization of the magnetic behaviors for the Y and Gd derivatives confirmed the strong cyano-mediated {Ni-W} interaction (J(NiW) = 27.1 and 28.5 cm(-1)) compared to the {Ni-Gd} interaction (J(NiGd) = 2.17 cm(-1)). The characteristic features for slow relaxation of the magnetization are observed for two Tb derivatives, but these are modulated by the crystal phase. Analysis of the frequency dependence of the alternating current susceptibility data yielded U(eff)/k(B) = 15.3 K and tau(0) = 4.5 x 10(-7) s for one derivative whereas no maxima of chi(M)'' appear above 2 K for the second one.

Antiferromagnetism in a 20% Ho-80% Tb alloy single crystal

DEFF Research Database (Denmark)

Lebech, Bente

1968-01-01

20% Ho-80% Tb exhibits two magnetic phases, similar to those of Tb. The spiral turn angle varies from 31.1° to 21.4°. A minimum effective spin for the occurrence of stable simple ferromagnetic structure at low temperatures is predicted....

Energy transfer and tunable multicolor emission and paramagnetic properties of GdF3:Dy(3+),Tb(3+),Eu(3+) phosphors.

Science.gov (United States)

Guan, Hongxia; Sheng, Ye; Xu, Chengyi; Dai, Yunzhi; Xie, Xiaoming; Zou, Haifeng

2016-07-20

A series of Dy(3+), Tb(3+), Eu(3+) singly or doubly or triply doped GdF3 phosphors were synthesized by a glutamic acid assisted one-step hydrothermal method. The samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and photoluminescence (PL) spectroscopy. The results show that the synthesized samples are all pure GdF3. The obtained samples have a peanut-like morphology with a diameter of about 270 nm and a length of about 600 nm. Under UV excitation, GdF3:Dy(3+), GdF3:Tb(3+) and GdF3:Eu(3+) samples exhibit strong blue, green and red emissions, respectively. By adjusting their relative doping concentrations in the GdF3 host, the different color hues of green and red light are obtained by co-doped Dy(3+), Tb(3+) and Tb(3+), Eu(3+) ions in the GdF3 host, respectively. Besides, there exist two energy transfer pairs in the GdF3 host: (1) Dy(3+) → Tb(3+) and (2) Tb(3+) → Eu(3+). More significantly, in the Dy(3+), Tb(3+), and Eu(3+) tri-doped GdF3 phosphors, white light can also be achieved upon excitation of UV light by adjusting the doping concentration of Eu(3+). In addition, the obtained samples also exhibit paramagnetic properties at room temperature (300 K) and low temperature (2 K). It is obvious that multifunctional Dy(3+), Tb(3+), Eu(3+) tri-doped GdF3 materials including tunable multicolors and intrinsic paramagnetic properties may have potential applications in the field of full-color displays.

Optical fiber magnetic field sensors with TbDyFe magnetostrictive thin films as sensing materials.

Science.gov (United States)

Yang, Minghong; Dai, Jixiang; Zhou, Ciming; Jiang, Desheng

2009-11-09

Different from usually-used bulk magnetostrictive materials, magnetostrictive TbDyFe thin films were firstly proposed as sensing materials for fiber-optic magnetic field sensing characterization. By magnetron sputtering process, TbDyFe thin films were deposited on etched side circle of a fiber Bragg Grating (FBG) as sensing element. There exists more than 45pm change of FBG wavelength when magnet field increase up to 50 mT. The response to magnetic field is reversible, and could be applicable for magnetic and current sensing.

Magnetism of DyMn2 and HoMn2 - 57Fe and 119Sn Moessbauer studies

International Nuclear Information System (INIS)

Krop, K.; Haeufler, T.; Hilscher, G.; Steiner, W.

1995-01-01

Moessbauer spectra were measured for two Laves phase compounds DyMn 2 and HoMn 2 in which manganese was substituted to 0.5% with 57 Fe and to 0.2% with 119 Sn. At 4.2 K the 57 Fe and 119 Sn spectra of the Dy compound were unambiguously fitted each with two Zeeman patterns (with relative contributions to the spectra 3:1) corresponding to two different Mn sites - magnetic and nonmagnetic. Transferred hyperfine fields at 119 Sn were found to be proportional to the magnetic moment of Dy and its ferromagnetic component, corroborating the magnetic structure found in neutron diffraction (ND) experiment. The same procedure was carried on with the spectra measured for the Ho compound, but the above mentioned proportionality was not found. ((orig.))

Effect of Nb on magnetic and mechanical properties of TbDyFe alloys

Science.gov (United States)

Wang, Naijuan; Liu, Yuan; Zhang, Huawei; Chen, Xiang; Li, Yanxiang

2018-03-01

The intrinsic brittleness in giant magnetostrictive material TbDyFe alloy has devastating influence on the machinability and properties of the alloy, thus affecting its applications. The purpose of this paper is to study the mechanical properties of the TbDyFe alloy by alloying with Nb element. The samples (Tb0.3Dy0.7)xFe2xNby (y = 0, 0.01, 0.04, 0.07, 0.1; 3x + y = 1) were melted in an arc melting furnace under high purity argon atmosphere. The microstructure, magnetostrictive properties and mechanical performance of the alloys were studied systematically. The results showed that NbFe2 phases were observed in the alloys with the addition of Nb. Moreover, both the NbFe2 phases and rare earth (RE)-rich phases were increased with the increasing of Nb element. The mechanical properties results revealed that the fracture toughness of the alloy with the addition of Nb enhanced 1.5-5 times of the Nb-free alloy. Both the NbFe2 phase and the RE-rich phase had the ability to prevent crack propagation, so that they can strengthen the REFe2 body. However, NbFe2 phase is a paramagnetic phase, which can reduce the magnetostrictive properties of the alloy by excessive precipitation.

Peculiarity of component interaction in {l_brace}Y, Dy{r_brace}-Mn-Sn ternary systems

Energy Technology Data Exchange (ETDEWEB)

Romaka, V.V. [Department of Materials Engineering and Applied Physics, Lviv Polytechnic National University, Ustyyanovycha Str. 5, 79013 Lviv (Ukraine); Konyk, M. [Inorganic Chemistry Department, Ivan Franko Lviv National University, Kyryla and Mefodiya Str. 6, 79005 Lviv (Ukraine); Romaka, L., E-mail: romakal@franko.lviv.ua [Inorganic Chemistry Department, Ivan Franko Lviv National University, Kyryla and Mefodiya Str. 6, 79005 Lviv (Ukraine); Pavlyuk, V. [Inorganic Chemistry Department, Ivan Franko Lviv National University, Kyryla and Mefodiya Str. 6, 79005 Lviv (Ukraine); Jan Dlugosz University, Institute of Chemistry, Environmental Protection and Biotechnology, al. Armii Krajowej 13/15, 42200 Czestochowa (Poland); Ehrenberg, H. [Institute for Complex Materials, IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden (Germany); Tkachuk, A. [Inorganic Chemistry Department, Ivan Franko Lviv National University, Kyryla and Mefodiya Str. 6, 79005 Lviv (Ukraine)

2011-07-14

Highlights: > {l_brace}Y, Dy{r_brace}-Mn-Sn ternary systems at 770 K are characterized by formation of stannides with general compositions RMn{sub 6}Sn{sub 6} and R{sub 4}Mn{sub 4}Sn{sub 7}. > The crystal structure of YMn{sub 6}Sn{sub 6} was determined by single crystal and powder diffraction methods. > Structural analysis showed that Dy{sub 4}Mn{sub 4}Sn{sub 7} compound is disordered. > Isostructural R{sub 4}Mn{sub 4}Sn{sub 7} compounds were also found with Gd, Tb, Ho, Er, Tm(confirmed), Yb, and Lu. - Abstract: The phase equilibria in the Y-Mn-Sn and Dy-Mn-Sn ternary systems were studied at 770 K by means of X-ray and metallographic analyses in the whole concentration range. Both Y-Mn-Sn and Dy-Mn-Sn systems are characterized by formation of two ternary compounds RMn{sub 6}Sn{sub 6} (MgFe{sub 6}Ge{sub 6}-type, space group P6/mmm) and R{sub 4}Mn{sub 4}Sn{sub 7} (Zr{sub 4}Co{sub 4}Ge{sub 7}-type, space group I4/mmm). The disorder in Dy{sub 4}Mn{sub 4}Sn{sub 7} compound was found by single crystal method. Compounds with the same type of structure were also found with Gd, Tb, Ho, Er, Tm (confirmed), Yb, and Lu and their lattice parameters were determined.

Recoil and conversion electron considerations of the {sup 166}Dy/{sup 166}Ho in vivo generator

Energy Technology Data Exchange (ETDEWEB)

Zeevaart, J.R. [North-West Univ., Mmabatho (South Africa). CARST; Szuecs, Z. [Nesca (South African Nuclear Energy Corporation Ltd.), Pretoria (South Africa). Radiochemistry; Hungarian Academy of Sciences, Debrecen (Hungary). Inst. of Nuclear Research; Takacs, S.; Jarvis, N. [Hungarian Academy of Sciences, Debrecen (Hungary). Inst. of Nuclear Research; Jansen, D. [Nesca (South African Nuclear Energy Corporation Ltd.), Pretoria (South Africa). Radiochemistry

2012-07-01

The use of radionuclides as potential therapeutic radiopharmaceuticals is increasingly investigated. An important aspect is the delivery of the radionuclide to the target, i.e. the radionuclide is not lost from the chelating agent. For in vivo generators, it is not only the log K of complexation between the metal ion and the chelator that is important, but also whether the daughter radionuclide stays inside the chelator after decay of the parent radionuclide. In our previous work, we showed that the classical recoil effect is only applicable for decays with a Q value higher than 0.6 MeV (in the atomic mass range around 100). However, Zhernosekov et al. published a result for {sup 140}Nd/{sup 140}Pr (Q = 0.222 MeV) which indicated that > 95% of the daughter ({sup 140}Pr) was lost by a DOTA chelator upon decay of {sup 140}Nd. The authors ascribed this to the ''post-effect''. Their experiment was repeated with the {sup 166}Dy/{sup 166}Ho generator to ascertain whether our calculations were correct. It was found that 72% of the daughter ({sup 166}Ho) was liberated from the DOTA chelator, indicating that the 'post effect' does exist in contrast to our recoil calculations. Upon further investigation, we determined that one should not only consider recoil energy levels but also the mode of decay which was able to explain the partial recoil found for {sup 166}Dy/{sup 166}Ho. It is concluded for the {sup 166}Dy/{sup 166}Ho system that the low recoil energy of the daughter nucleus {sup 166}Ho is not a sufficient reason to rule out release of the nuclide from chelators. On the other hand, we found that the ratio of the {sup 166}Ho that gets released corresponds to the ratio of relaxation of Ho atoms via the Auger process. (orig.)

Host-sensitized luminescence properties in CaNb2O6:Ln(3+) (Ln(3+) = Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+)) phosphors with abundant colors.

Science.gov (United States)

Li, Kai; Liu, Xiaoming; Zhang, Yang; Li, Xuejiao; Lian, Hongzhou; Lin, Jun

2015-01-05

A series of Ln(3+) (Ln(3+) = Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+)) ion doped CaNb2O6 (CNO) phosphors have been prepared via the conventional high-temperature solid-state reaction route. The X-ray diffraction (XRD) and structure refinement, diffuse reflection, photoluminescence (PL), and fluorescent decay curves were used to characterize the as-prepared samples. Under UV radiation, the CNO host present a broad emission band from about 355 to 605 nm centered around 460 nm originating from the NbO6 octahedral groups, which has spectral overlaps with the excitation of f-f transitions of Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+) in CNO:Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+) samples. They show both host emission and respective emission lines derived from the characteristic f-f transitions of activators, which present different emission colors owing to the energy transfer from the NbO6 group in the host to Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+) with increasing activator concentrations. The decreases of decay lifetimes of host emissions in CNO:Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+) demonstrate the energy transfer from the hosts to Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+). The energy transfer mechanisms in CNO:Eu(3+)/Tb(3+)/Dy(3+) phosphors have been determined to be a resonant type via dipole-dipole mechanisms. For CNO:Sm(3+), the metal-metal charge transfer transition (MMCT) might contribute to the different variations of decay lifetimes and emission intensity from CNO:Eu(3+)/Tb(3+)/Dy(3+) samples. The best quantum efficiency is 71.2% for CNO:0.01/0.02Dy(3+). The PL properties of as-prepared materials indicate the promising application in UV-pumped white-emitting lighting diodes field.

Clinical trial of {sup 165}Dy-HMA and {sup 166}Ho-CHICO in the treatment of Rheumatoid knee synovitis

Energy Technology Data Exchange (ETDEWEB)

Kim, S. Y.; Yoo, D. H.; Bae, S. C.; Jun, J. B. [Hanyang University, Seoul (Korea, Republic of); Lim, S. M.; Hong, S. W.; Lee, S. Y.; Cheon, D. G.; Kim, S. J. [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

1997-07-01

The untreated, chronic synovial inflammation leads to pannus formation and eventual destruction of the articular cartilage. In cases where medical therapy was unsuccessful, surgical or radiation synovectomy is necessary especially in the knee joints. The advantages of radiation synovectomy over surgical synovectomy are (1) greater destruction of diseased synovium, (2) reduced potential for blood clots and infection, (3) no requirement for anesthesia, and (4) less costly and less time consuming. Recently KAERI developed Dy-165 HMA, which was characterized by the absence of iron and a higher concentration of dysprosium. And then more recently KAERI also developed {sup 166}Ho-CHICO, which was characterized by relatively longer half-life(26.8 hr), more biological due to organic nature of chitosan, more even spatial distribution due to colloidal solution and more absorbable to synovium than Dy-165 HMA. We studied to evaluate the efficacy and safety of radiation synovectomy with Dy-165 HMA and {sup 166}Ho-CHICO in chronic rheumatoid synovitis with knee. The present study indicates that the Dy-165 HMA and {sup 166}Ho-CHICO are an effective and safe agent for radiation synovectomy. But further large scaled long-term follow up study and controlled study with steroid only are required. 15 refs. (author)

Separation and recovery of high grade Dy2O3 by solvent extraction process with DEHPA in kerosene

International Nuclear Information System (INIS)

Mishra, S.L.; Thakur, N.V.; Koppiker, K.S.

1993-01-01

During the solvent extraction (SX) fractionation of rare earths chloride obtained from monazite, a heavy RE (HRE) fraction assaying 60% Y 2 O 3 is produced. This is purified further to 93% Y 2 O 3 by another SX cycle. During this step most of Dy and Tb get separated to yield a concentrate assaying >50% Dy 2 O 3 . An attempt has been made to process this Dy rich concentrate to obtain a high grade Dy 2 O 3 by a SX route using DEHPA in kerosene. The distribution data (D vs H i + ) of Dy have been generated experimentally at various metal concentrations and similar data for other metals present (Gd, Tb, Y, Er and Ho) have been derived using a mathematical expression developed in our laboratory. Based on this information mathematical models for extraction behaviour of these HRE have been derived and used in a computer program developed for multicomponent system. This program has been utilised to optimise the process parameters to obtain 95-97% pure Dy 2 O 3 at about 90% recovery. The parameters have been experimentally confirmed and Dy 2 O 3 95.5% pure w.r.t. Tb was obtained at about 90% recovery, thus confirming the validity of the program. This paper presents data obtained during these investigations. (author). 6 refs., 5 tabs

Induced assembly and photoluminescence of lanthanum (Tb, Eu, Dy) complexes/ZnO/polyethylene glycol hybrid phosphors

Energy Technology Data Exchange (ETDEWEB)

Yan Bing [Department of Chemistry, Tongji University, Siping Road 1239, Shanghai 200092 (China)]. E-mail: byan@tongji.edu.cn; Chen Xi [Department of Chemistry, Tongji University, Siping Road 1239, Shanghai 200092 (China); Wu Jianhua [Department of Chemistry, Tongji University, Siping Road 1239, Shanghai 200092 (China)

2007-08-31

Some novel kinds of hybrid phosphors were assembled with lanthanum (Tb, Eu, Dy) complexes (with four kinds of terbium complexes is 2,4-dihydroxybenzonic acid (DHBA), 1,10-phenanthroline (phen), acetylacetone (AA) and nicotinic acid (Nic), respectively) doped ZnO/PEG particles by co-precipitation approach derived from Zn(CH{sub 3}COO){sub 2} (Zn(AC){sub 2}), NaOH, PEG as precursors at room temperature. The characteristic luminescence spectra for f-f transitions of Tb{sup 3+}, Eu{sup 3+}, Dy{sup 3+} were observed. It is worthy to point out that ZnO is the excellent host for lanthanum ions by the assembly of PEG matrices.

The effect of Nb and Zr addition on the microstructural features and magnetic properties of Tb0.3Dy0.7Fe1.95

International Nuclear Information System (INIS)

Palit, Mithun; Arout Chelvane, J.; Basumatary, Himalay; Pandian, S.; Chandrasekaran, V.

2009-01-01

Alloys of Tb 0.3 Dy 0.7 Fe 1.95-x Nb x and Tb 0.3 Dy 0.7 Fe 1.95-x Zr x , with x = 0-0.075, were prepared by conventional melting and casting under vacuum. The magnetostriction improved remarkably with the individual addition of Nb and Zr. It is seen from the microstructural features that Nb addition results in the formation of NbFe 2 as the primary phase while Zr addition results in the depletion of (Tb,Dy)Fe 3 phase owing to the substitution of Zr for rare earths in the main phase

Magnetism of DyMn{sub 2} and HoMn{sub 2} - {sup 57}Fe and {sup 119}Sn Moessbauer studies

Energy Technology Data Exchange (ETDEWEB)

Krop, K. [University of Min. and Metall., Krakow (Poland). Dept. of Solid State Phys.; Zukrowski, J. [University of Min. and Metall., Krakow (Poland). Dept. of Solid State Phys.; Przewoznik, J. [University of Min. and Metall., Krakow (Poland). Dept. of Solid State Phys.; Marzec, J. [University of Min. and Metall., Krakow (Poland). Dept. of Solid State Phys.; Wiesinger, G. [Institute for Experimental Physics, Technical University, Wiedner Hauptstrasse 8-10, A-1040 Vienna (Austria); Haeufler, T. [Institute for Experimental Physics, Technical University, Wiedner Hauptstrasse 8-10, A-1040 Vienna (Austria); Hilscher, G. [Institute for Experimental Physics, Technical University, Wiedner Hauptstrasse 8-10, A-1040 Vienna (Austria); Steiner, W. [Institute for Applied and Technical Physics, Technical University, Wiedner Hauptstrasse 8-10, A-1040 Vienna (Austria)

1995-05-01

Moessbauer spectra were measured for two Laves phase compounds DyMn{sub 2} and HoMn{sub 2} in which manganese was substituted to 0.5% with {sup 57}Fe and to 0.2% with {sup 119}Sn. At 4.2 K the {sup 57}Fe and {sup 119}Sn spectra of the Dy compound were unambiguously fitted each with two Zeeman patterns (with relative contributions to the spectra 3:1) corresponding to two different Mn sites - magnetic and nonmagnetic. Transferred hyperfine fields at {sup 119}Sn were found to be proportional to the magnetic moment of Dy and its ferromagnetic component, corroborating the magnetic structure found in neutron diffraction (ND) experiment. The same procedure was carried on with the spectra measured for the Ho compound, but the above mentioned proportionality was not found. ((orig.)).

New intermetallic compounds Ln(Ag, AL)4 (Ln-Y, Gd, Tb, Dy) and their structure

International Nuclear Information System (INIS)

Kuz'ma, Yu.B.; Stel'makhovich, B.M.

1990-01-01

By the methods of X-ray analysis crystal structure of compounds Ln(Ag,Al) 4 , where Ln-Y, Gd, Tb, Dy, posessing rhombic structure, is determined. The intermetallics have been prepared for the first time. Ways of atom distribution and their coordinates in DyAg 0.55 Al 3.45 structure (a=0.4296(1), b=04179(1), c=0.9995(3), R=0.093) are specified. Other compounds are formed in case of LnAgAl 3 compositions. Interatomic distances in Dy(Ag,Al) 4 structure are considered. A supposition is made on the formation in Ln-Ag-Al systems of a greater number of intermetallic compounds

Magnetism in RRhGe (R = Tb, Dy, Er, Tm): An experimental and theoretical study

Energy Technology Data Exchange (ETDEWEB)

Gupta, Sachin [Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076 (India); Suresh, K.G., E-mail: suresh@phy.iitb.ac.in [Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076 (India); Nigam, A.K. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Lukoyanov, A.V. [Institute of Metal Physics, Russian Academy of Sciences, Ural Branch, Yekaterinburg 620137 (Russian Federation); Ural Federal University, Yekaterinburg 620002 (Russian Federation)

2015-08-15

Highlights: • RRhGe (R = Tb, Dy, Er, Tm) compounds show low temperature antiferromagnetic ordering. • All compounds show field induced metamagnetic transitions. • Some of these compounds show large magnetocaloric effect and magnetoresistance. • Change of sign in MR take place on temperature variation. - Abstract: RRhGe (R = Tb, Dy, Er, Tm) compounds have been studied by different experimental probes and theoretical ab initio calculations. These compounds show very interesting magnetic and transport properties. All the compounds are antiferromagnetic with some of them showing spin-reorientation transition at low temperatures. The magnetocaloric effect estimated from magnetization data shows high values in all these compounds. Magnetoresistance is negative near the ordering temperatures and positive at low temperatures. The electronic structure calculations accounting for electronic correlations in the 4f rare-earth shell reveal the closeness of the antiferromagnetic ground state and other types of magnetic orderings in the rare-earth sublattice. These calculations are also in agreement with the experimental results.

KCa4(BO33:Ln3+ (Ln = Dy, Eu, Tb phosphors for near UV excited white–light–emitting diodes

Directory of Open Access Journals (Sweden)

Allu Amarnath Reddy

2013-02-01

Full Text Available A series of doped KCa4(BO33:Ln3+ (Ln: Dy, Eu and Tb compositions were synthesized by solid–state reaction method and their photoluminescent properties were systematically investigated to ascertain their suitability for application in white light emitting diodes. The X–ray diffraction (XRD and nuclear magnetic resonance (MAS–NMR data indicates that Ln3+–ions are successfully occupied the non–centrosymmetric Ca2+ sites, in the orthorhombic crystalline phase of KCa4(BO33 having space group Ama2, without affecting the boron chemical environment. The present phosphor systems could be efficiently excitable at the broad UV wavelength region, from 250 to 350 nm, compatible to the most commonly available UV light–emitting diode (LED chips. Photoluminescence studies revealed optimal near white–light emission for KCa4(BO33 with 5 wt.% Dy3+ doping, while warm white–light (CIE; X = 0.353, Y = 0.369 is obtained at 1wt.% Dy3+ ion concentration. The principle of energy transfer between Eu3+ and Tb3+ also demonstrates the potential white–light from KCa4(BO33:Eu3+,Tb3+ phosphor. Whereas, single Tb3+ and Eu3+–doped systems showed bright green (Tb3+ and red (Eu3+ emissions, respectively. Having structural flexibility along with remarkable chemical/thermal stability and suitable quantum efficiency these phosphors can be promising candidates as white–light–emitter for near UV LEDs.

Coercivity enhancement of Dy-free Nd–Fe–B sintered magnets by intergranular adding Ho{sub 63.4}Fe{sub 36.6} alloy

Energy Technology Data Exchange (ETDEWEB)

Liang, Liping; Ma, Tianyu, E-mail: maty@zju.edu.cn; Wu, Chen; Zhang, Pei; Liu, Xiaolian; Yan, Mi, E-mail: mse_yanmi@zju.edu.cn

2016-01-01

High coercivity Nd–Fe–B sintered magnets serving in high-temperature environments always consume expensive and scarce heavy rare-earth Dy, which has simulated considerable interest to reduce Dy usage. In this work, coercivity of Dy-free magnets was investigated through intergranular adding eutectic Ho{sub 63.4}Fe{sub 36.6} powders. The coercivity increases gradually up to 4 wt% Ho{sub 63.4}Fe{sub 36.6} addition, however the remanence starts to deteriorate drastically as the addition is over 2.5 wt%. Coercivity above 18.0 kOe is obtained at the expense of a slight reduction in remanence through optimizing the addition amount and sintering conditions. The coercivity enhancement is explained through microstructural observations and elemental distribution analysis. (i) (Nd, Ho){sub 2}Fe{sub 14}B shell forms in the outer region of 2:14:1 phase grains, strengthening the local magnetic anisotropy filed, (ii) RE-rich grain boundary phase with low Fe content is thickened, weakening the magnetic coupling between adjacent 2:14:1 phase grains, and (iii) 2:14:1 phase grains are refined upon lowering sintering temperature, reducing the microstructural defects and the stray fields aroused from neighboring grains. - Highlights: • Eutectic Ho{sub 63.4}Fe{sub 36.6} powders were intergranular added to NdFeB sintered magnets. • The doped Dy-free magnet possessed coercivity of 18.0 kOe, remanence of 13.15 kGs. • (Nd, Ho){sub 2}Fe{sub 14}B shell formed in the surface of the matrix grains, increasing the H{sub A}. • Thick grain boundaries with low Fe content formed, decoupling the matrix grains. • By sintered at lower temperature, the matrix phase grains were refined.

Hydrothermal synthesis, characterization, and luminescence of Ca_2B_2O_5:RE (RE = Eu"3"+, Tb"3"+, Dy"3"+) nanofibers

International Nuclear Information System (INIS)

Yang, Li; Wan, Yingpeng; Li, Yuze; Pu, Yinfu; Huang, Yanlin; Chen, Cuili; Seo, Hyo Jin

2016-01-01

Ca_2B_2O_5:RE (RE = Eu"3"+, Tb"3"+, Dy"3"+) nanofibers were synthesized by the hydrothermal reaction method. The structural refinement was conducted on the base of the X-ray powder diffraction (XRD) measurements. The surface properties of the Ca_2B_2O_5:RE (RE = Eu"3"+, Tb"3"+, Dy"3"+) nanofibers were investigated by the measurements such as the scanning electron microscope (SEM), transmission electron microscope (TEM), and the energy dispersive spectrum (EDS). The nanofiber has a diameter of about 100 nm and a length of several micrometers. The luminescence properties such as photoluminescence excitation (PLE) and emission spectra (PL), decay lifetime, color coordinates, and the absolute internal quantum efficiency (QE) were reported. Ca_2B_2O_5:Eu"3"+ nanofibers show the red luminescence with CIE coordinates of (x = 0.41, y = 0.51) and the luminescence lifetime of 0.63 ms. The luminescence of Ca_2B_2O_5:Tb"3"+ nanofibers is green color (x = 0.29, y = 0.53) with the lifetime of 2.13 ms. However, Dy"3"+-doped Ca_2B_2O_5 nanofibers present a single-phase white-color phosphor with the fluorescence decay of 3.05 ms. Upon near-UV excitation, the absolute quantum efficiency is measured to be 65, 35, and 37 % for Eu"3"+-, Tb"3"+-, Dy"3"+-doped Ca_2B_2O_5 nanofibers, respectively. It is suggested that Ca_2B_2O_5:RE (RE = Eu"3"+, Tb"3"+, Dy"3"+) nanofibers could be an efficient phosphor for lighting and display.

Investigation on the formation of the preferred orientations in a TbDyFe alloy with directional solidification

International Nuclear Information System (INIS)

Jiang Chengbao; Xu Huibin

1999-01-01

The formation of the preferred orientations in a TbDyFe alloy was studied by transmission electron microscopy (TEM). It was found that there were several different preferred orientations in the experimental TbDyFe alloy with directional solidification. left angle 110 right angle, left angle 112 right angle and left angle 113 right angle preferred orientations were observed in this alloy solidified by our self-made super high gradient temperature directional solidification device. The preferred orientations changed with the variation of the solidification conditions. Two {111} twinning systems resulted in the left angle 110 right angle preferred orientation and a single {111} twinning system resulted in the left angle 112 right angle preferred orientation. The twinning displacement was observed and this formatted the left angle 113 right angle preferred orientation. (orig.)

Rare earth-rich cadmium compounds RE{sub 10}TCd{sub 3} (RE = Y, Tb, Dy, Ho, Er, Tm, Lu; T = Rh, Pd, Ir, Pt) with an ordered Co{sub 2}Al{sub 5}-type structure

Energy Technology Data Exchange (ETDEWEB)

Block, Theresa; Klenner, Steffen; Heletta, Lukas; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie

2018-04-01

Eighteen new rare earth-rich intermetallic phases RE{sub 10}TCd{sub 3} (RE = Y, Tb, Dy, Ho, Er, Tm, Lu; T = Rh, Pd, Ir, Pt) were obtained by induction melting of the elements in sealed niobium ampoules followed by annealing in muffle furnaces. All samples were characterized by X-ray powder diffraction. The structures of four representatives were refined from single-crystal X-ray diffractometer data: ordered Co{sub 2}Al{sub 5} type, P6{sub 3}/mmc, a = 951.2(1), c = 962.9(2) pm, wR = 0.0460, 595 F{sup 2} values, 20 parameters for Er{sub 10}RhCd{sub 3}; a = 945.17(4), c = 943.33(4), wR = 0.0395, 582 F{sup 2} values, 21 parameters for Lu{sub 9.89}PdCd{sub 3.11}; a = 964.16(6), c = 974.93(6) pm, wR = 0.0463, 614 F{sup 2} values, 21 parameters for Y{sub 10}Ir{sub 1.09}Cd{sub 2.91}; a = 955.33(3), c = 974.56(3) pm, wR = 0.0508, 607 F{sup 2} values, 22 refined parameters for Dy{sub 9.92}IrCd{sub 3.08}. Refinements of the occupancy parameters revealed small homogeneity ranges resulting from RE/Cd, respectively T/Cd mixing. The basic building units of the RE{sub 10}TCd{sub 3} phases are transition metal-centered RE{sub 6} trigonal prisms (TP) that are condensed with double-pairs of empty RE{sub 6} octahedra via common triangular faces. A second type of rods is formed by slightly distorted RE3 rate at Cd{sub 6}RE{sub 6} icosahedra which are condensed via Cd{sub 3} triangular faces. The shortest interatomic distances occur for RE-T, compatible with strong covalent bonding interactions. Temperature dependent magnetic susceptibility measurements were performed for RE{sub 10}RhCd{sub 3} (RE = Dy-Tm, Lu), RE{sub 10}IrCd{sub 3} (RE = Er, Tm, Lu) and RE{sub 10}PtCd{sub 3} (RE = Y, Lu). While Y{sub 10}PtCd{sub 3} and Lu{sub 10}TCd{sub 3} (T = Rh, Ir, Pt) show Pauli paramagnetic behavior, the compounds containing paramagnetic rare earth elements show Curie-Weiss behavior (the experimental magnetic moments indicate stable trivalent RE{sup 3+}) and magnetic ordering at low temperatures

Narrow spectral emission CaMoO{sub 4}: Eu{sup 3+}, Dy{sup 3+}, Tb{sup 3+} phosphor crystals for white light emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Khanna, A. [Smart Lighting Engineering Research Center, 110, 8th Street, Troy, New York, 12180 (United States); Electrical, Computer and Systems Engineering Department, Rensselaer Polytechnic Institute, 110, 8th Street, Troy, New York, 12180 (United States); Dutta, P.S., E-mail: duttap@rpi.edu [Smart Lighting Engineering Research Center, 110, 8th Street, Troy, New York, 12180 (United States); Electrical, Computer and Systems Engineering Department, Rensselaer Polytechnic Institute, 110, 8th Street, Troy, New York, 12180 (United States)

2013-02-15

Alkaline earth metal molybdates are promising candidates as a host material for high efficiency narrow spectral emission phosphors. These phosphors could potentially be used for the fabrication of phosphor-converted light emitting diodes (pc-LEDs). Phosphor crystals of calcium molybdate doped with rare earth dopant Ln{sup 3+}(Ln=Eu, Dy, Tb) grown using flux growth method have been shown to exhibit higher excitation efficiency than the powders synthesized by solid-state reaction process. Molybdenum (VI) oxide has been found to be a suitable flux for growing large size optically transparent high quality crystals at a temperature around 1100 Degree-Sign C. Using the excitation wavelengths of 465 nm, 454 nm and 489 nm for CaMoO{sub 4}: Eu{sup 3+}, CaMoO{sub 4}: Dy{sup 3+} and CaMoO{sub 4}: Tb{sup 3+}, respectively, intense emission lines at wavelengths of 615 nm, 575 nm and 550 nm were observed. The optimized doping concentrations of 12%, 2% and 5% for Eu{sup 3+}, Dy{sup 3+} and Tb{sup 3+}, respectively, provided the highest luminescence intensity. - Graphical Abstract: CaMoO{sub 4}: Eu{sup 3+} phosphor crystals grown using a molybdenum (VI) oxide flux exhibited around 1.5 times the emission intensity of powders obtained from solid-state reaction at the same synthesis temperature. These crystals were found to efficiently emit 615 nm red light when excited by near UV light up to a wavelength of 395 nm. Highlights: Black-Right-Pointing-Pointer CaMoO{sub 4}: Ln{sup 3+} (Ln=Eu{sup 3+}, Dy{sup 3+}, Tb{sup 3+}) phosphor crystals were successfully grown using high temperature flux (solutions) containing molybdenum (VI) oxide or lithium chloride. Black-Right-Pointing-Pointer Narrow spectral emission at 615 nm, 575 nm and 550 nm, respectively, was observed from CaMoO{sub 4}: Ln{sup 3+} (Ln=Eu{sup 3+}, Dy{sup 3+}, Tb{sup 3+}) phosphor crystals. Black-Right-Pointing-Pointer The optimized doping concentrations of Eu{sup 3+}, Dy{sup 3+}, Tb{sup 3+} in CaMoO{sub 4} for highest

Levels and transitions in 160Dy following the decay of 160Tb

International Nuclear Information System (INIS)

Noordin bin Ibrahim; Stewart, N.M.

1989-01-01

The level scheme of 160 Dy has been established from γ-γ coincidence measurement following the β-decay of 160 Tb. Ge(Li) detectors were coupled to a Dual Parameter Spectrometer for data collection. A total of fifteen new gamma transitions were observed. Two energy levels at 1285 and 1288 keV were confirmed while four levels at 1349, 1670, 1694 and 1804 keV were found to be populated for the first time from β-decay of 160 Tb: Three levels at 1230, 1338 and 1507 keV are newly suggested. Relative intensities for the transitions and branching ratios of the energy levels were determined. Comparisons are made with theoretical predictions of IBA calculations, two considerations were taken: normal shell closure (Z 50/82) and subshell closure (Z = 64). (author)

Series of isostructural planar lanthanide complexes [Ln(III)4(mu3-OH)2(mdeaH)2(piv)8] with single molecule magnet behavior for the Dy4 analogue.

Science.gov (United States)

Abbas, Ghulam; Lan, Yanhua; Kostakis, George E; Wernsdorfer, Wolfgang; Anson, Christopher E; Powell, Annie K

2010-09-06

A series of five isostructural tetranuclear lanthanide complexes of formula [Ln(4)(mu(3)-OH)(2)(mdeaH)(2)(piv)(8)], (mdeaH(2) = N-methyldiethanolamine; piv = pivalate; Ln = Tb (1), Dy (2), Ho (3), Er (4), and Tm (5)) have been synthesized and characterized. These clusters have a planar "butterfly" Ln(4) core. Magnetically, the Ln(III) ions are weakly coupled in all cases; the Dy(4) compound 2 shows Single Molecule Magnet (SMM) behavior.

Resonance spin memory in low-energy gamma-ray spectra from Sb, Tb, Ho and Ta odd-odd compound nuclei

International Nuclear Information System (INIS)

Olejniczak, U.; Gundorin, N.A.; Pikelner, L.B.; Serov, D.G.; Przytula, M.

2002-01-01

The low-energy gamma-ray spectra from neutron resonance capture with natural samples of Sb, Tb, Ho and Ta were measured using a HPGe detector at the IBR-30 pulsed reactor (JINR, Dubna). The resonance spin memory effect in the spectra from the odd-odd compound nuclei of 122 Sb, 160 Tb and 166 Ho was found to be quite distinct. For the 182 Ta compound nucleus it proved to be rather weak

A binuclear Fe(III)Dy(III) single molecule magnet. Quantum effects and models.

Science.gov (United States)

Ferbinteanu, Marilena; Kajiwara, Takashi; Choi, Kwang-Yong; Nojiri, Hiroyuki; Nakamoto, Akio; Kojima, Norimichi; Cimpoesu, Fanica; Fujimura, Yuichi; Takaishi, Shinya; Yamashita, Masahiro

2006-07-19

The binuclear [FeIII(bpca)(mu-bpca)Dy(NO3)4], having Single Molecule Magnet (SMM) properties, belonging to a series of isostructural FeIIILnIII complexes (Ln = Eu, Gd, Tb, Dy, Ho) and closely related FeIILnIII chain structures, was characterized in concise experimental and theoretical respects. The low temperature magnetization data showed hysteresis and tunneling. The anomalous temperature dependence of Mössbauer spectra is related to the onset of magnetic order, consistent with the magnetization relaxation time scale resulting from AC susceptibility measurements. The advanced ab initio calculations (CASSCF and spin-orbit) revealed the interplay of ligand field, spin-orbit, and exchange effects and probed the effective Ising nature of the lowest states, involved in the SMM and tunneling effects.

Study of hyperfine interactions in intermetallic compounds Gd(Ni,Pd,Cu)In, Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In; Estudo de interacoes hiperfinas em compostos intermetalicos Gd(Ni,Pd,Cu)In, Tb(Ni,Pd)In, Dy(Ni,Pd)In e Ho(Ni,Pd)In

Energy Technology Data Exchange (ETDEWEB)

Lapolli, Andre Luis

2006-07-01

Systematic behavior of magnetic hyperfine field (B{sub hf}) in the intermetallic compounds Gd(Ni,Pd,Cu)In Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In was studied by Perturbed Gamma-Gamma Angular Correlation spectroscopy. The measurements of B{sub hf} were carried out at the rare earth atom and in sites using the nuclear probes {sup 140}Ce and {sup 11}'1Cd respectively. The variation of hyperfine field with temperature, in most cases, follows the Brillouin function predicted from the molecular field theory. The hyperfine field values at rare earth atom sites obtained from {sup 140}Ce probe as well as at in sites obtained from {sup 111}Cd probe for each series of compounds were extrapolated to zero Kelvin B{sub hf}(T=0) from these curves. These values were compared with the values of the literature for other compounds containing the same rare earth element and all of them show a linear relationship with the ordering temperature. This indicates that the main contribution to B{sub hf} comes from the conduction electron polarization (CEP) through Fermi contact interaction and the principal mechanism of magnetic interaction in these compounds can be described by the RKKY type interaction. The values of B{sub hf}(T=0) for each family of intermetallic compounds RNiIn and RPdIn when plotted as a function of 4f spin projection of rare earth element also shows a linear relationship. Exceptions are the results for the compounds RNiIn obtained with {sup 111}Cd probe where a small deviation from linearity is observed. The results of the measurements carried out with the {sup 111}Cd probe were also analyzed to obtain the hyperfine parameters of the quadrupole interaction as a function of temperature for RPdln and GdNiIn compounds. The results show that for the compound GdPdIn there might be some Gd-In disorder at high temperature. (author)

Study of hyperfine interactions in intermetallic compounds Gd(Ni,Pd,Cu)In, Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In; Estudo de interacoes hiperfinas em compostos intermetalicos Gd(Ni,Pd,Cu)In, Tb(Ni,Pd)In, Dy(Ni,Pd)In e Ho(Ni,Pd)In

Energy Technology Data Exchange (ETDEWEB)

Lapolli, Andre Luis

2006-07-01

Systematic behavior of magnetic hyperfine field (B{sub hf}) in the intermetallic compounds Gd(Ni,Pd,Cu)In Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In was studied by Perturbed Gamma-Gamma Angular Correlation spectroscopy. The measurements of B{sub hf} were carried out at the rare earth atom and in sites using the nuclear probes {sup 140}Ce and {sup 11}'1Cd respectively. The variation of hyperfine field with temperature, in most cases, follows the Brillouin function predicted from the molecular field theory. The hyperfine field values at rare earth atom sites obtained from {sup 140}Ce probe as well as at in sites obtained from {sup 111}Cd probe for each series of compounds were extrapolated to zero Kelvin B{sub hf}(T=0) from these curves. These values were compared with the values of the literature for other compounds containing the same rare earth element and all of them show a linear relationship with the ordering temperature. This indicates that the main contribution to B{sub hf} comes from the conduction electron polarization (CEP) through Fermi contact interaction and the principal mechanism of magnetic interaction in these compounds can be described by the RKKY type interaction. The values of B{sub hf}(T=0) for each family of intermetallic compounds RNiIn and RPdIn when plotted as a function of 4f spin projection of rare earth element also shows a linear relationship. Exceptions are the results for the compounds RNiIn obtained with {sup 111}Cd probe where a small deviation from linearity is observed. The results of the measurements carried out with the {sup 111}Cd probe were also analyzed to obtain the hyperfine parameters of the quadrupole interaction as a function of temperature for RPdln and GdNiIn compounds. The results show that for the compound GdPdIn there might be some Gd-In disorder at high temperature. (author)

Magnetostriction-strain-induced enhancement and modulation of photovoltaic performance in Si-p-n/Tb{sub x}Dy{sub 1-x}Fe{sub 2} composite

Energy Technology Data Exchange (ETDEWEB)

Wu, Zheng [School of Materials Science and Technology, China University of Geosciences, Beijing (China); Department of Physics and College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua (China); Zhang, Yihe [School of Materials Science and Technology, China University of Geosciences, Beijing (China); Fang, Cong; Ma, Ke; Lin, He; Jia, Yanmin; Chen, Jianrong [Department of Physics and College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua (China); Wang, Yu; Chan, Helen Lai Wa [Department of Applied Physics, The Hong Kong Polytechnic University (China)

2014-03-15

High photovoltaic efficiency is a key index in the application of silicon (Si) solar cells. In this study, a composite of a photovoltaic Si p-n junction solar cell and a magnetostrictive Tb{sub x}Dy{sub 1-x}Fe{sub 2} alloy was fabricated. By utilizing the magnetostrictive strain to modulate the energy bandgap of Si, the open-circuit voltage and the maximum photovoltaic output power of the Si p-n junction solar cell could be enhanced by ∝12% and 9.1% under a dc magnetic field of ∝250 mT, respectively. The significantly enhanced photovoltaic performance and the simple fabrication process make the Si-p-n/Tb{sub x}Dy{sub 1-x}Fe{sub 2} composite a promising material for high-efficiency solar cell devices. The structure of the proposed Si-p-n/Tb{sub x}Dy{sub 1-x}Fe{sub 2} laminated composite. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Transport properties of RCo_2B_2C with R = Dy, Ho, and Pr single

Science.gov (United States)

Duran, Alejandro; Escudero, Roberto

2002-03-01

Single crystals of (Dy, Ho, Pr)Co_2B_2C have been grown by a cold copper crucible method. Metallurgical and structural studies indicate that this borocarbide family melts incongruently and crystallizes as a derivative structure of the ThCr_2Si_2. The family accepts rare earth atoms depending on the type of transition metals used to form the compound. For instance with Ni atoms, all lanthanides ranging from the large lanthanum to lutetium ions are reported to form RNi_2B_2C single crystals, so far no single crystals have been obtained when changing Ni by Cobalt. A comparison of the structural parameters of the RCo_2B_2C with the RNiHo, Pr) compounds indicate that the atomic distance between transition metal atoms contracts with the insertion of the Co ion, resulting in an increasing of the c parameter and decreasing volume. Several recent reports published in the current literature related on the physical properties of RCo_2B_2C (R = rare earth metals and Y) have been only performed on polycrystalline samples, they commonly contain small amounts of second phases. High quality single crystals are necessaries in order to better understand the physical properties, such as anisotropy in the transport and in the magnetic properties. In this report we show magnetic susceptibility and resistivity measurements performed in single crystals in the ab-plane and c direction for 2 - 320 K temperature range for the three single crystals of (Dy, Ho, Pr)Co_2B_2C.

Comparison of the Supercooled Spin Liquid States in the Pyrochlore Magnets Dy2Ti2O7 and Ho2Ti2O7

Science.gov (United States)

Eyal, Anna; Eyvazov, Azar B.; Dusad, Ritika; Munsie, Timothy J. S.; Luke, Graeme M.; Davis, J. C. Séamus

Despite a well-ordered crystal structure and strong magnetic interactions between the Dy or Ho ions, no long-range magnetic order has been detected in the pyrochlore titanates Ho2Ti2O7 and Dy2Ti2O7. The low temperature state in these materials is governed by spin-ice rules. These constrain the Ising like spins in the materials, yet does not result in a global broken symmetry state. To explore the actual magnetic phases, we simultaneously measure the time- and frequency-dependent magnetization dynamics of Dy2Ti2O7 and Ho2Ti2O7 using toroidal, boundary-free magnetization transport techniques. We demonstrate a distinctive behavior of the magnetic susceptibility of both compounds, that is indistinguishable in form from the permittivity of supercooled dipolar liquids. Moreover, we show that the microscopic magnetic relaxation times for both materials increase along a super-Arrhenius trajectory also characteristic of supercooled glass-forming liquids. Both materials therefore exhibit characteristics of a supercooled spin liquid. Strongly-correlated dynamics of loops of spins is suggested as a possible mechanism which could account for these findings. Potential connections to many-body spin localization will also be discussed.

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...

EPR experiments in LiTbF4, LiHoF4, and LiErF4 at submillimeter frequencies

DEFF Research Database (Denmark)

Magariño, J.; Tuchendler, J.; Beauvillain, P.

1980-01-01

Electron-paramagnetic-resonance experiments in LiTbF4, LiHoF4, and LiErF4 have been performed at frequencies between 70 and 600 GHz, in magnetic fields up to 60 kG and in the temperature range 1.4......Electron-paramagnetic-resonance experiments in LiTbF4, LiHoF4, and LiErF4 have been performed at frequencies between 70 and 600 GHz, in magnetic fields up to 60 kG and in the temperature range 1.4...

Enhanced fluorescence of Tb(III), Dy(III) perchlorate by salicylic acid in bis(benzoylmethyl) sulfoxide complexes and luminescence mechanism

International Nuclear Information System (INIS)

Li Wenxian; Zheng Yushan; Sun Xiaojun; Chai Wenjuan; Ren Tie; Shi Xiaoyan

2010-01-01

Two novel ternary rare earth perchlorate complexes had been synthesized by using bis(benzoylmethyl) sulfoxide as first ligand (L=C 6 H 5 COCH 2 SOCH 2 COC 6 H 5 ), salicylic acid as second ligand (L ' =C 6 H 4 OHCOO - ). The compounds were characterized by elemental analysis, TG-DSC and molar conductivities in DMF solution. The composition was suggested as [REL 5 L'](ClO 4 ) 2 .nH 2 O (RE=Tb, Dy; n=6, 8 ). Based on IR, 1 HNMR and UV spectra, it showed that the first ligand, bis(benzoylmethyl) sulfoxide (L), bonded with Tb(III), Dy(III) ions by the oxygen atom of sulfinyl group. The second ligand, salicylic acid group (L'), not only bonded with RE(III) ions by one oxygen atom of carboxyl group but also bonded with RE(III) ions by oxygen atom of phenolic hydroxyl group. In bis(benzoylmethyl) sulfoxide system, fluorescent spectra of the complexes showed that the luminescence of Tb(III), Dy(III) ions was enhanced by the second ligand salicylic acid. The ternary complexes had stronger fluorescence than the binary ones where only bis(benzoylmethyl) sulfoxide acted as ligand. Phosphorescent spectra of the two ligands indicated that the coordination of salicylic acid resulted in the matching extent increasing between the triplet state of ligand and excited state of the rare earths. The relationship between fluorescence lifetime and fluorescence intensity was also discussed.

Effect of rapid quenching on the magnetism and magnetocaloric effect of equiatomic rare earth intermetallic compounds RNi (R = Gd, Tb and Ho)

Energy Technology Data Exchange (ETDEWEB)

Rajivgandhi, R. [Department of Physics, Indian Institute of Technology Madras, Chennai 600 036 (India); Arout Chelvane, J. [Defence Metallurgical Research Laboratory, Hyderabad 500 058 (India); Quezado, S.; Malik, S.K. [Departamento de F’ısica Teorica e Experimental, Universidade Federal do Rio Grande do Norte, Natal 59072-970 (Brazil); Nirmala, R., E-mail: nirmala@physics.iitm.ac.in [Department of Physics, Indian Institute of Technology Madras, Chennai 600 036 (India)

2017-07-01

Highlights: • Melt-spinning yields microcrystalline RNi (R = Gd, Tb and Ho) samples with texture. • The texture-induced anisotropy affects magnetic and magnetocaloric properties. • Melt-spinning helps one engineer magnetocaloric effect in rare-earth compounds. - Abstract: Magnetocaloric effect (MCE) in RNi (where R = Gd, Tb and Ho) compounds has been studied in their arc-melted and melt-spun forms. The compound GdNi has the orthorhombic CrB-type structure (Space group Cmcm, No. 63) and the compound HoNi has the orthorhombic FeB-type structure (Space group Pnma, No. 62) at room temperature regardless of their synthesis condition. However, arc-melted TbNi orders in a monoclinic structure (Space group P2{sub 1}/m, No. 11) and when it is rapidly quenched to a melt-spun form, it crystallizes in an orthorhombic structure (Space group Pnma, No. 62). The arc-melted GdNi, TbNi and HoNi compounds order ferromagnetically at ∼69 K, ∼67 K and ∼36 K (T{sub C}) respectively. While the melt-spun GdNi shows about 6 K increase in T{sub C}, the ordering temperature of TbNi remains nearly the same in both arc-melted and melt-spun forms. In contrast, a reduction in T{sub C} by about 8 K is observed in melt-spun HoNi, when compared to its arc-melted counterpart. Isothermal magnetic entropy change, ∆S{sub m}, calculated from the field dependent magnetization data indicates an enhanced relative cooling power (RCP) for melt-spun GdNi for field changes of 20 kOe and 50 kOe. A lowered RCP value is observed in melt-spun TbNi and HoNi. These changes could have resulted from the competing shape anisotropy and the granular microstructure induced by the melt-spinning process. Tailoring the MCE of rare earth intermetallic compounds by suitably controlled synthesis techniques is certainly one of the directions to go forward in the search of giant magnetocaloric materials.

Magnetoelectric effect in two-layered self-biased composites Tb{sub 0.12}Dy{sub 0.2}Fe{sub 0.68}/epoxy - PbZr{sub 0.53}Ti{sub 0.47}O{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Kalgin, A.V.; Gridnev, S.A.; Popov, I.I. [Voronezh State Technical University, Voronezh (Russian Federation)

2017-03-15

Direct magnetoelectric (ME) effect in two-layered Tb{sub 0.12}Dy{sub 0.2}Fe{sub 0.68}/Epoxy - PbZr{sub 0.53}Ti{sub 0.47}O{sub 3} composites containing magnetostrictive layers of the epoxy with distributed in it Tb{sub 0.12}Dy{sub 0.2}Fe{sub 0.68} granules and piezoelectric layers of the PbZr{sub 0.53}Ti{sub 0.47}O{sub 3} ceramics was studied. It was found, that the gradient distribution of Tb{sub 0.12}Dy{sub 0.2}Fe{sub 0.68} granules in magnetostrictive layers induces the internal (self-biased) magnetic field. This field leads to the increase in ME responses in composites with the gradient distribution of Tb{sub 0.12}Dy{sub 0.2}Fe{sub 0.68} granules in magnetostrictive layers as compared with ME responses in composites with the random distribution of Tb{sub 0.12}Dy{sub 0.2}Fe{sub 0.68} granules in magnetostrictive layers, which does not induce the internal magnetic field. We revealed the possibility of controlling and determining values of the internal magnetic field in composites and conditions for obtaining optimal ME responses. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Magnetic ordering of Hf{sub 3}Ni{sub 2}Si{sub 3}-type {Sm, Tb, Er}{sub 3}Co{sub 2}Ge{sub 3} and {Tb, Ho}{sub 3}Ni{sub 2}Ge{sub 3} compounds

Energy Technology Data Exchange (ETDEWEB)

Morozkin, A.V., E-mail: morozkin@tech.chem.msu.ru [Department of Chemistry, Moscow State University, Leninskie Gory, House 1, Building 3, Moscow, GSP-1, 119991 (Russian Federation); Yapaskurt, V.O. [Department of Petrology, Geological Faculty Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation); Nirmala, R. [Indian Institute of Technology Madras, Chennai 600036 (India); Quezado, S.; Malik, S.K. [Departamento de Física Teórica e Experimental, Universidade Federal do Rio Grande do Norte, Natal 59082-970 (Brazil); Mozharivskyj, Y. [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1 (Canada); Isnard, O. [CNRS, Institut. Néel, 25 rue des Martyrs BP166 x, F-38042 Grenoble (France); Université Grenoble Alpes, Inst. Néel, F-38042 Grenoble (France)

2017-02-15

The magnetic ordering of Hf{sub 3}Ni{sub 2}Si{sub 3}-type {Sm, Tb, Er}{sub 3}Co{sub 2}Ge{sub 3} and {Tb, Ho}{sub 3}Ni{sub 2}Ge{sub 3} compounds (space group Cmcm, oC32) was investigated via magnetization measurements and neutron diffraction study in a zero-applied field. {Sm, Tb, Er}{sub 3}Co{sub 2}Ge{sub 3} and Ho{sub 3}Ni{sub 2}Ge{sub 3} exhibit field sensitive complex antiferromagnetic orderings with T{sub N}=51 K, T{sub m}=10 K for Sm{sub 3}Co{sub 2}Ge{sub 3}, T{sub N}=34 K, T{sub m}=13 K for Tb{sub 3}Co{sub 2}Ge{sub 3}, T{sub N}=7 K for Er{sub 3}Co{sub 2}Ge{sub 3} and T{sub N}=11 K for Ho{sub 3}Ni{sub 2}Ge{sub 3}. At 2 K and above the critical field of ~5 kOe, 20 kOe, 4 kOe and 7 kOe for Sm{sub 3}Co{sub 2}Ge{sub 3}, Tb{sub 3}Co{sub 2}Ge{sub 3}, Er{sub 3}Co{sub 2}Ge{sub 3} and Ho{sub 3}Ni{sub 2}Ge{sub 3}, respectively, saturation magnetizations per rare-earth atom are 6.5 μ{sub B} for Tb{sub 3}Co{sub 2}Ge{sub 3}, 7.0 μ{sub B} for Er{sub 3}Co{sub 2}Ge{sub 3} and 8.0 μ{sub B} for Ho{sub 3}Ni{sub 2}Ge{sub 3} in the field of 140 kOe, whereas magnetization of Sm{sub 3}Co{sub 2}Ge{sub 3} has an antiferromagnetic behaviour. The isothermal magnetic entropy change, ΔS{sub m}, indicates a field-induced ferromagnetic ordering in Sm{sub 3}Co{sub 2}Ge{sub 3}, Tb{sub 3}Co{sub 2}Ge3, Er{sub 3}Co{sub 2}Ge{sub 3} and Ho{sub 3}Ni{sub 2}Ge{sub 3} with a maximal ΔS{sub m} value of −10.9 J/kg K for Ho{sub 3}Ni{sub 2}Ge{sub 3} at 11 K for a field change of 50 kOe. In a zero-applied magnetic field, below T{sub N}=33 K and down to T{sub m}{sup ND}=15 K Tb{sub 3}Ni{sub 2}Ge{sub 3} shows an ac-antiferromagnetic ordering with the C2′/c magnetic space group, a K{sub 0}=[0, 0, 0] propagation vector and a a{sub Tb3Ni2Ge3}×b{sub Tb3Ni2Ge3}×c{sub Tb3Ni2Ge3} magnetic unit cell. Below T{sub m}{sup ND}=15 K, its magnetic structure is a sum of the ac-antiferromagnetic component with the C2′/c magnetic space group of the K{sub 0} vector and a sine-modulated a

Magnetic structure of RPdSn (R=Tb, Ho) single crystal compounds under strong magnetic field

International Nuclear Information System (INIS)

Andoh, Y.; Kurisu, M.; Nakamoto, G.; Tsutaoka, T.; Kawano, S.

2003-01-01

Rare earth compounds RTX, where R stands for rare earth elements, T for Ni, Pd or Rh, and X for Sn or Ge, crystallize to a rhombic ε-TiNiSi structure. Only rare earth elements R contribute to magnetic properties since T and X atoms are nonmagnetic. The competition between RKKY indirect interaction and large magnetic anisotropy generates many complicated magnetic phases. At a low temperature phase, complicated magnetisms such as meta-magnetism were observed in magnetization curves with many steps. In previous experiments dealing with RPdSn where R means Tb or Ho, some characteristics of magnetic properties of these compounds were deduced from magnetization measurements and neutron diffraction without external magnetic field. In this report, the change of magnetic scattering of neutron diffraction was studied under external magnetic fields in order to reveal the mechanism of the phase transformations of the compounds. The difference between TbPdSn and HoPdSn compounds was observed in magnetic field dependence of the wave vectors of the magnetic scattering. Two independent wave vectors in magnetic scattering existed in HoPdSn compound. (Y. Kazumata)

Study of hyperfine interactions in intermetallic compounds Gd(Ni,Pd,Cu)In, Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In

International Nuclear Information System (INIS)

Lapolli, Andre Luis

2006-01-01

Systematic behavior of magnetic hyperfine field (B hf ) in the intermetallic compounds Gd(Ni,Pd,Cu)In Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In was studied by Perturbed Gamma-Gamma Angular Correlation spectroscopy. The measurements of B hf were carried out at the rare earth atom and in sites using the nuclear probes 140 Ce and 11 '1Cd respectively. The variation of hyperfine field with temperature, in most cases, follows the Brillouin function predicted from the molecular field theory. The hyperfine field values at rare earth atom sites obtained from 140 Ce probe as well as at in sites obtained from 111 Cd probe for each series of compounds were extrapolated to zero Kelvin B hf (T=0) from these curves. These values were compared with the values of the literature for other compounds containing the same rare earth element and all of them show a linear relationship with the ordering temperature. This indicates that the main contribution to B hf comes from the conduction electron polarization (CEP) through Fermi contact interaction and the principal mechanism of magnetic interaction in these compounds can be described by the RKKY type interaction. The values of B hf (T=0) for each family of intermetallic compounds RNiIn and RPdIn when plotted as a function of 4f spin projection of rare earth element also shows a linear relationship. Exceptions are the results for the compounds RNiIn obtained with 111 Cd probe where a small deviation from linearity is observed. The results of the measurements carried out with the 111 Cd probe were also analyzed to obtain the hyperfine parameters of the quadrupole interaction as a function of temperature for RPdln and GdNiIn compounds. The results show that for the compound GdPdIn there might be some Gd-In disorder at high temperature. (author)

161Dy Moessbauer spectroscopy of the intermetallic compounds DyNi2Si2, DyNi2Ge2 and DyAg2Si2

International Nuclear Information System (INIS)

Onodera, Hideya; Murata, Akifumi; Koizuka, Masaaki; Ohashi, Masayoshi; Yamaguchi, Yasuo

1994-01-01

161 Dy Moessbauer spectroscopic study has been performed on DyNi 2 Si 2 , DyNi 2 Ge 2 and DyAg 2 Si 2 in order to clarify microscopic properties of antiferromagnets with incommensurate and sinusoidally moment-modulated structure. The experiments were done using the standard 161 Tb Moessbauer sources prepared by neutron irradiation at the Japan Material Testing Reactor. The Moessbauer spectra of DyNi 2 Si 2 are analyzed satisfactorily by a single set of hyperfine parameters, and hence the sinusoidal moment-modulation is considered to be realized through a distribution of spin relaxation rate. The broadened spectra of DyNi 2 Ge 2 are fitted tentatively by three subspectra. It seems for DyNi 2 Ge 2 that the incommensurate arrangement of Dy moments differed in magnitude as well as the distribution of spin relaxation rate originates the moment modulation. The fact that the spectrum of DyAg 2 Si 2 at 3 K consists of two distinct subspectra ensures the complicated antiferromagnetic structure where two kinds of Dy moments differed in magnitude are arranged noncollinearly. (author)

Synthesis and photoluminescence characteristics of (Y,Gd)BO3:RE (RE = Eu(3+), Ce(3+), Dy(3+) and Tb(3+)) phosphors for blue chip and near-UV white LEDs.

Science.gov (United States)

Rangari, V V; Singh, V; Dhoble, S J

2016-03-01

A series of Eu(3+)-, Ce(3+)-, Dy(3+)- and Tb(3+)-doped (Y,Gd)BO3 phosphors was synthesized by a solid-state diffusion method. X-Ray diffraction confirmed their hexagonal structure and the scanning electron microscopy results showed crystalline particles. The excitation spectra revealed that (Y,Gd)BO3 phosphors doped with Eu(3+), Ce(3+), Dy(3+) and Tb(3+) are effectively excited with near UV-light of 395 nm/blue light, 364, 351 and 314 nm, respectively. Photoluminescence spectra of Eu(3+)-, Ce(3+)- and Tb(3+)/Dy(3+)-doped phosphor showed intense emission of reddish orange, blue and white light, respectively. The phosphor Y0.60Gd0.38BO3:Ce0.02 showed CIE 1931 color coordinates of (0.158, 0.031) and better color purity compared with commercially available blue BAM:Eu(2+) phosphor. The phosphor (Y,Gd)BO3 doped with Eu(3+), Dy(3+) and Tb(3+) showed CIE 1931 color coordinates of (0.667, 0.332), (0.251, 0.299) and (0.333, 0.391) respectively. Significant photoluminescence characteristics of the prepared phosphors indicate that they might serve as potential candidates for blue chip and near-UV white light-emitting diode applications. Copyright © 2015 John Wiley & Sons, Ltd.

Magnetic domain structure, crystal orientation, and magnetostriction of Tb{sub 0.27}Dy{sub 0.73}Fe{sub 1.95} solidified in various high magnetic fields

Energy Technology Data Exchange (ETDEWEB)

Gao, Pengfei [Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, Shenyang 110819 (China); Liu, Tie, E-mail: liutie@epm.neu.edu.cn [Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, Shenyang 110819 (China); Dong, Meng [Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, Shenyang 110819 (China); Yuan, Yi [School of Materials and Metallurgy, Northeastern University, Shenyang 110819 (China); Wang, Qiang [Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, Shenyang 110819 (China)

2016-03-01

In this paper, we studied how applying a high magnetic field during solidification of Tb{sub 0.27}Dy{sub 0.73}Fe{sub 1.95} alloys affected their magnetic domain structure, crystal orientation, and magnetostriction. We observed the morphology of the magnetic domain during solidification, finding it change with the applied field: from fiber like (0 T) to dot like and closure mixed (4.4 T) to fiber like (8.8 T) to fishbone like (11.5 T). The alloy solidified at 4.4 T showed the best contrast of light and dark in its domain image, widest magnetic domain, fastest magnetization, and highest magnetostriction; this alloy is followed in descending order by the alloys solidified at 11.5 T, 8.8 T, and 0 T. The orientation of the (Tb, Dy)Fe{sub 2} phase changed with magnetic field from random (0 T) to 〈111〉 (4.4 T) to 〈113〉 (8.8 T) to 〈110〉 (11.5 T). The improvement in magnetostriction was likely caused by modification of both the magnetization process and the alloy microstructure. - Highlights: • We present how magnetic field affects magnetic domain structure of Tb{sub 0.27}Dy{sub 0.73}Fe{sub 1.95}. • Morphology and width of magnetic domain change with increasing magnetic field. • Magnetization and magnetostriction of alloy change with increasing magnetic field. • A transformation of random–〈111〉–〈113〉–〈110〉 for (Tb, Dy)Fe{sub 2} orientation forms.

Measurement of the K X-ray absorption jump factors and jump ratios of Gd, Dy, Ho and Er by attenuation of a Compton peak

International Nuclear Information System (INIS)

Budak, G.; Polat, R.

2004-01-01

The X-ray absorption jump factor and jump ratio of Gd, Dy, Ho and Er were measured with a Si(Li) detector by attenuation, with Gd, Dy, Ho and Er foil, a Compton peak produced by the scattering of the 59.5 keV Am-241 Gamma rays. Al was chosen as secondary exciter. The experimental absorption jump factors and jump ratios are compared with the theoretical estimates of WinXcom (Radiat. Phys. Chem. 60 (2001) 23), McMaster (Compilation of X-ray cross sections UCRL-50174, 1969; Sec. II. Rev. I), Broll (X-ray Spectrom 15 (1986) 271), Hubbel and Seltzer (NISTIR (1995) 5632) and Budak (Radiat. Meas. accepted for publication). The present results constitute the first measurement for this combination of energy and elements, and good agreement is obtained between experiment and theory

Progress in sintered NdFeB magnets with Dy/Tb grain boundary diffusion%晶界扩散Dy/Tb烧结NdFeB研究进展

Institute of Scientific and Technical Information of China (English)

刘涛; 周磊; 张昕; 程星华; 林德; 喻晓军; 李波

2011-01-01

由于汽车和电子应用领域对节能电动机的需求,在VCM、电动机、信号发生器、手机和MRI等领域中得到广泛应用的烧结钕铁硼在电动机市场应用会进一步扩展.剩磁和矫顽力等磁性能的提高有利于烧结磁体在电动机市场快速增长.通常,烧结磁体一些性能的改善总是以牺牲其他性能为代价.而晶界扩散Dy/Tb烧结磁体与传统的同类磁体相比较,其矫顽力和剩磁可同时得以改善,本文对晶界扩散Dy/Tb钕铁硼的一些研究成果进行了综述和总结.晶界扩散Dy/Tb过程中烧结磁体晶界的成份和微观组织的变化对烧结磁体磁性能改善至为重要.%Many new applications of Nd-Fe-B magnets, such as voice coil motor (VCM) in hard disc drive, motors, generators, mobile phone, MRI, etc, are expected to expand in future because of strong energy saving requirements from the automobile and electric appliances markets. Magnetic property improvement in residual (Br) and coercive force (Hcj) helps the rapid growth of the motor market. In many instances, an improvement of some characteristics of sintered magnet is achieved but only at the expense of other characteristics. It has been found that Dy/Tb grain boundary diffusion processed Nd-Fe-B sintered magnets have improvement in both the highest remanence and cocercivity among conventional rare-earth permanent mgnets, which have been introduced in this paper. The influence of Dy/Tb grain boundary diffusion on composition and microstructure of grain boundaries phase is a key point for magnetic property improvement of sintered magnet.

Characterization, electrical transport and magnetic properties of the rare earth misfit layer compounds (TbS)(1.21)NbS2, (TbS)(1.20)TaS2, (DyS)(1.22)NbS2 and (DyS)(1.21)TaS2

NARCIS (Netherlands)

Zhou, W.Y.; Meetsma, A.; deBoer, J.L.; Wiegers, G.A

1996-01-01

X-ray powder and single-crystal X-ray diffraction of the title compounds showed that they are planar intergrowth compounds, built of alternating sandwiches TS2 (T=Nb, Ta) and double layers LnS (Ln=Tb, Dy), present in three orientational variants related by rotations of 120 degrees around the c axis

Syntheses, structures, and magnetic properties of a family of heterometallic heptanuclear [Cu5Ln2] (Ln = Y(III), Lu(III), Dy(III), Ho(III), Er(III), and Yb(III)) complexes: observation of SMM behavior for the Dy(III) and Ho(III) analogues.

Science.gov (United States)

Chandrasekhar, Vadapalli; Dey, Atanu; Das, Sourav; Rouzières, Mathieu; Clérac, Rodolphe

2013-03-04

Sequential reaction of the multisite coordination ligand (LH3) with Cu(OAc)2·H2O, followed by the addition of a rare-earth(III) nitrate salt in the presence of triethylamine, afforded a series of heterometallic heptanuclear complexes containing a [Cu5Ln2] core {Ln = Y(1), Lu(2), Dy(3), Ho(4), Er(5), and Yb(6)}. Single-crystal X-ray crystallography reveals that all the complexes are dicationic species that crystallize with two nitrate anions to compensate the charge. The heptanuclear aggregates in 1-6 are centrosymmetrical complexes, with a hexagonal-like arrangement of six peripheral metal ions (two rare-earth and four copper) around a central Cu(II) situated on a crystallographic inversion center. An all-oxygen environment is found to be present around the rare-earth metal ions, which adopt a distorted square-antiprismatic geometry. Three different Cu(II) sites are present in the heptanuclear complexes: two possess a distorted octahedral coordination sphere while the remaining one displays a distorted square-pyramidal geometry. Detailed static and dynamic magnetic properties of all the complexes have been studied and revealed the single-molecule magnet behavior of the Dy(III) and Ho(III) derivatives.

Synthesis and magneto-structural studies on a new family of carbonato bridged 3d-4f complexes featuring a [CoLn(CO3)] (Ln = La, Gd, Tb, Dy and Ho) core: slow magnetic relaxation displayed by the cobalt(ii)-dysprosium(iii) analogue.

Science.gov (United States)

Majee, Mithun Chandra; Towsif Abtab, Sk Md; Mondal, Dhrubajyoti; Maity, Manoranjan; Weselski, Marek; Witwicki, Maciej; Bieńko, Alina; Antkowiak, Michał; Kamieniarz, Grzegorz; Chaudhury, Muktimoy

2018-03-06

A new family of [3 + 3] hexanuclear 3d-4f complexes [(μ 3 -CO 3 ){Co II Ln III L(μ 3 -OH)(OH 2 )} 3 ]-(ClO 4 )·mC 2 H 5 OH·nH 2 O (1-5) [Ln = La (1), Gd (2), Tb (3), Dy (4), and Ho (5)] have been prepared in moderate to high yields (62-78%) following a self-assembly reaction between the ligand 6,6',6''-(nitrilotris(methylene))tris-(2-methoxy-4-methylphenol) (H 3 L), Co(OAc) 2 ·4H 2 O and the lanthanide ion precursors in the mandatory presence of tetrabutylammonium hydroxide. During the reaction, atmospheric carbon dioxide is fixed in the product molecule as a bridging carbonato ligand which connects all the three lanthanide centers of this molecular assembly through a rare η 2 :η 2 :η 2 -μ 3 mode of bridging as revealed from X-ray crystallography. The metal centers in all these compounds, except the Gd III analogue (2), are coupled in antiferromagnetic manner while the nature of coupling in the CoGd complex is ferromagnetic. DFT calculations revealed that this ferromagnetic interaction occurs most likely by the Co II -Gd III superexchange, mediated via the bridging oxygen atoms. Only the Co II -Dy III compound (4) displayed a slow relaxation of the magnetization at a very low temperature as established by AC susceptibility measurements. The data provides an estimation of the activation energy U/k B = 9.2 K and the relaxation time constant τ 0 = 1.0 × 10 -7 s.

Tunable luminescence and energy transfer properties in Na{sub 3}Bi(PO4){sub 2}:Eu{sup 3+}, Tb{sup 3+}, Dy{sup 3+}, Sm{sup 3+} phosphors with high thermal stability

Energy Technology Data Exchange (ETDEWEB)

Zhu, Zizhong; Fu, Guangsheng; Yang, Yong; Yang, Zhiping, E-mail: yangzp2005@sohu.com; Li, Panlai, E-mail: li_panlai@126.com

2017-04-15

Na{sub 3}Bi(PO{sub 4}){sub 2}:Eu{sup 3+}/Tb{sup 3+}/Dy{sup 3+}/Sm{sup 3+} phosphors were synthesized via a high-temperature solid-state reaction method. The X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), diffuse reflection, photoluminescence (PL) and fluorescent decay curves were utilized to characterize the obtained phosphors. Under n-UV excitation, Na{sub 3}Bi(PO{sub 4}){sub 2}:Eu{sup 3+}/Tb{sup 3+}/Dy{sup 3+}/Sm{sup 3+} samples show the characteristic f-f emissions and present red, green, yellow and orange emission, respectively. When Tb{sup 3+}, Dy{sup 3+} and Sm{sup 3+} were co-doped into the Na{sub 3}Bi(PO{sub 4}){sub 2}:Eu{sup 3+} phosphors, tunable emission colors can be obtained and can be efficiently adjusted by varying the doping ions and the doping concentration. The energy transfer mechanisms were investigated in detail and demonstrated that there is an efficient energy transfer from Tb{sup 3+}, Dy{sup 3+} and Sm{sup 3+} to Eu{sup 3+} via a dipole-dipole interaction mechanism. Additional, as the temperature increases from RT to 150 °C, the PL intensity of Tb{sup 3+}-Eu{sup 3+}, Dy{sup 3+}-Eu{sup 3+} and Sm{sup 3+}-Eu{sup 3+} co-doped phosphors decreased to 86%, 85% and 88%, respectively, which prove good thermal stability. All the CIE coordinates of as-prepared phosphors are displayed and show abundant colors, making these materials have potential applications for n-UV-excited white-LEDs.

Tunable emission in Ln3+ (Ce3+/Dy3+, Ce3+/Tb3+) doped KNa3Al4Si4O16 phosphor synthesized by combustion method

Science.gov (United States)

Kolte, M. M.; Pawade, V. B.; Bhattacharya, A. B.; Dhoble, S. J.

2018-05-01

Ln3+ (Ln = Ce3+/Dy3+, Ce3+/Tb3+) doped KNa3Al4Si4O16 phosphor has been synthesized by Combustion method (CS) at 550° C successfully. Ln3+ (Ln = Ce3+, Dy3+, Tb3+) ions when doped in KNa3Al4Si4O16 host lattice, it shows blue and green emission band under the near Ultraviolet (NUV) excitation wavelength. The Photoluminescence excitation (PLE) and emission spectra are observed due to f-f and d-f transition of rare earth ions. Also, an effective energy transfer (ET) study from Ce3+ → Dy3+ and Ce3+ → Tb3+ ions has been studied and confirmed on the basis of Dexter-Foster theory. Further synthesized phosphor is well characterized by XRD, SEM, TEM and decay time measurement. However, the analysis of crystallite size, lattice strain has been studied by using theoretical as well as experimental techniques. Hence, the observed tunable emission in Ln3+ doped KNa3Al4Si4O16 phosphor may be applicable for solid state lighting technology.

Magnetic Interactions in Tb and Tb-10% Ho from Inelastic Neutron Scattering

DEFF Research Database (Denmark)

Bjerrum Møller, Hans; Houmann, Jens Christian Gylden; Mackintosh, A.R.

1968-01-01

The magnon dispersion relations and lifetimes have been measured in Tb and a Tb‐10% Ho alloy by inelastic neutron scattering, in regions of both ferromagnetic and spiral ordering. In the ferromagnetic phase, the magnon energy is generally finite at zero wavevector and rises quadratically at low q....... The magnon energies scale approximately with the magnetization. In the spiral phase the magnon energy rises linearly from zero at low q. The Fourier‐transformed exchange parameter J(q) has pronounced peaks in the c direction, which are ascribed to transitions between states close to the Fermi surface....... These peaks are less pronounced in the ferromagnetic phase. The primary mechanism limiting the magnon lifetimes appears to be interaction with the conduction electrons. In the alloy, the lifetime for magnons propagating in the c direction in the ferromagnetic phase falls abruptly at about q  =  0.35 Å−1...

Tunable-color luminescence via energy transfer in NaCa13/18Mg5/18PO4:A (A = Eu2+/Tb3+/Mn2+, Dy3+) phosphors for solid state lighting.

Science.gov (United States)

Li, Kai; Fan, Jian; Mi, Xiaoyun; Zhang, Yang; Lian, Hongzhou; Shang, Mengmeng; Lin, Jun

2014-11-17

A series of NaCa13/18Mg5/18PO4(NCMPO):A (A = Eu(2+)/Tb(3+)/Mn(2+), Dy(3+)) phosphors have been prepared by the high-temperature solid-state reaction method. The X-ray diffraction (XRD) and Rietveld refinement, X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), cathodoluminescence (CL), decay lifetimes, and PL quantum yields (QYs) were utilized to characterize the phosphors. The pure crystalline phase of as-prepared samples has been demonstrated via XRD measurement and Rietveld refinements. XPS reveals that the Eu(2+)/Tb(3+)/Mn(2+) can be efficiently doped into the crystal lattice. NCMPO:Eu(2+)/Tb(3+)/Mn(2+) phosphors can be effectively excited under UV radiation, which show tunable color from purple-blue to red including white emission based on energy transfer from Eu(2+) to Tb(3+)/Mn(2+) ions. Under low-voltage electron beam bombardment, the NCMPO:A (A = Eu(2+)/Tb(3+)/Mn(2+), Dy(3+)) display their, respectively, characteristic emissions with different colors, and the CL spectrum of NCMPO:0.04Tb(3+) has the comparable intensity to the ZnO:Zn commercial product. In addition, the calculated CIE coordinate of NCMPO:0.04Tb(3+) (0.252, 0.432) is more saturated than it (0.195, 0.417). These results reveal that NCMPO:A (A = Eu(2+)/Tb(3+)/Mn(2+), Dy(3+)) may be potential candidate phosphors for WLEDs and FEDs.

Hydrothermal synthesis, characterization, and luminescence of Ca{sub 2}B{sub 2}O{sub 5}:RE (RE = Eu{sup 3+}, Tb{sup 3+}, Dy{sup 3+}) nanofibers

Energy Technology Data Exchange (ETDEWEB)

Yang, Li; Wan, Yingpeng; Li, Yuze; Pu, Yinfu; Huang, Yanlin, E-mail: huang@suda.edu.cn [Soochow University, State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science (China); Chen, Cuili; Seo, Hyo Jin, E-mail: hjseo@pknu.ac.kr [Pukyong National University, Department of Physics and Interdisciplinary Program of Biomedical Engineering (Korea, Republic of)

2016-04-15

Ca{sub 2}B{sub 2}O{sub 5}:RE (RE = Eu{sup 3+}, Tb{sup 3+}, Dy{sup 3+}) nanofibers were synthesized by the hydrothermal reaction method. The structural refinement was conducted on the base of the X-ray powder diffraction (XRD) measurements. The surface properties of the Ca{sub 2}B{sub 2}O{sub 5}:RE (RE = Eu{sup 3+}, Tb{sup 3+}, Dy{sup 3+}) nanofibers were investigated by the measurements such as the scanning electron microscope (SEM), transmission electron microscope (TEM), and the energy dispersive spectrum (EDS). The nanofiber has a diameter of about 100 nm and a length of several micrometers. The luminescence properties such as photoluminescence excitation (PLE) and emission spectra (PL), decay lifetime, color coordinates, and the absolute internal quantum efficiency (QE) were reported. Ca{sub 2}B{sub 2}O{sub 5}:Eu{sup 3+} nanofibers show the red luminescence with CIE coordinates of (x = 0.41, y = 0.51) and the luminescence lifetime of 0.63 ms. The luminescence of Ca{sub 2}B{sub 2}O{sub 5}:Tb{sup 3+} nanofibers is green color (x = 0.29, y = 0.53) with the lifetime of 2.13 ms. However, Dy{sup 3+}-doped Ca{sub 2}B{sub 2}O{sub 5} nanofibers present a single-phase white-color phosphor with the fluorescence decay of 3.05 ms. Upon near-UV excitation, the absolute quantum efficiency is measured to be 65, 35, and 37 % for Eu{sup 3+}-, Tb{sup 3+}-, Dy{sup 3+}-doped Ca{sub 2}B{sub 2}O{sub 5} nanofibers, respectively. It is suggested that Ca{sub 2}B{sub 2}O{sub 5}:RE (RE = Eu{sup 3+}, Tb{sup 3+}, Dy{sup 3+}) nanofibers could be an efficient phosphor for lighting and display.

Isolation of {sup 163}Ho from dysprosium target material by HPLC for neutrino mass measurements

Energy Technology Data Exchange (ETDEWEB)

Mocko, Veronika; Taylor, Wayne A.; Nortier, Francois M.; Engle, Jonathan W.; Pollington, Anthony D.; Kunde, Gerd J.; Rabin, Michael W.; Birnbaum, Eva R. [Los Alamos National Laboratory, Los Alamos, NM (United States). Chemistry Div.; Barnhart, Todd E.; Nickles, Robert J. [Univ. Wisconsinn, Madison, WI (United States). Dept. of Medical Physics

2015-07-01

The rare earth isotope {sup 163}Ho is of interest for neutrino mass measurements. This report describes the isolation of {sup 163}Ho from a proton-irradiated dysprosium target and its purification. A Dy metal target was irradiated with 16 MeV protons for 10 h. After target dissolution, {sup 163}Ho was separated from the bulk Dy via cation-exchange high performance liquid chromatography using 70 mmol dm{sup -3} α-hydroxyisobutyric acid as the mobile phase. Subsequent purification of the collected Ho fraction was performed to remove the α-hydroxyisobutyrate chelating agent and to concentrate the Ho in a low ionic strength aqueous matrix. The final solution was characterized by MC-ICP-MS to determine the {sup 163}Ho/{sup 165}Ho ratio, {sup 163}Ho and the residual Dy content. The HPLC purification process resulted in a decontamination factor 1.4 x 10{sup 5} for Dy. The isolated Ho fraction contained 24.8 ± 1.3 ng of {sup 163}Ho corresponding to holmium recovery of 72 ± 3%.

Synthesis, luminescence, and energy-transfer properties of β-Na2Ca4(PO4)2(SiO4):A (A = Eu(2+), Dy(3+), Ce(3+)/Tb(3+)) phosphors.

Science.gov (United States)

Li, Kai; Shang, Mengmeng; Geng, Dongling; Lian, Hongzhou; Zhang, Yang; Fan, Jian; Lin, Jun

2014-07-07

A series of β-Na2Ca4(PO4)2(SiO4) (β-NCPS):A (A = Eu(2+), Dy(3+), Ce(3+)/Tb(3+)) phosphors were prepared via a high-temperature solid-state reaction route. The X-ray diffraction, Fourier transform infrared, photoluminescence (PL), cathodoluminescence (CL) properties, fluorescent lifetimes, and absolute quantum yield were exploited to characterize the samples. Under UV radiation, the β-NCPS:Eu(2+) phosphors present bright green emissions, and the β-NCPS:Ce(3+) phosphors show strong blue emissions, which are attributed to their 4f(6)5d(1) → 4f(7) and 5d-4f allowed transitions, respectively. The β-NCPS:Ce(3+), Tb(3+) phosphors display intense tunable color from blue to green and high absolute quantum yields (81% for β-NCPS:0.12Ce(3+) and 83% for β-NCPS:0.12Ce(3+), 0.08Tb(3+)) when excited at 365 nm. Simultaneously, the energy transfer from Ce(3+) to Tb(3+) ions is deduced from the spectral overlap between Ce(3+) emission and Tb(3+) excitation spectra and demonstrated by the change of emission spectra and decay lifetimes. Moreover, the energy-transfer mechanism from Ce(3+) to Tb(3+) ions is confirmed to be exchange interaction according to the discussion of expression from Dexter and Reisfeld. Under a low-voltage electron-beam excitation, the β-NCPS:A (A = Eu(2+), Dy(3+), Ce(3+)/Tb(3+)) phosphors exhibit their characteristic emissions, and the emission profiles of β-NCPS:Ce(3+),Tb(3+) phosphors are obviously different from those of the PL spectra; this difference might be ascribed to their different luminescence mechanisms. These results in PL and CL properties suggest that β-NCPS:A (A = Eu(2+), Dy(3+), Ce(3+)/Tb(3+)) phosphors are potential candidates for solid-state lighting and field-emission displays.

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.

Entropy change at the magnetostructural transition in RCo2(R=Dy,Ho,Er)

International Nuclear Information System (INIS)

Herrero-Albillos, J.; Bartolome, F.; Garcia, L.M.; Casanova, F.; Labarta, A.; Batlle, X.

2006-01-01

Differential scanning calorimetry under applied magnetic field has been used to characterize the magnetocaloric effect in ErCo 2 , HoCo 2 , and DyCo 2 . The entropy change ΔS at the first-order magnetostructural transition present in these materials has been studied by inducing the transition; sweeping the temperature at a constant field and sweeping the field at a constant temperature. The corresponding values of ΔS differ significantly due to the broadness of the transition, i.e. the initial and final states involved when the transition is field or temperature induced are different. In the field-induced case, the additional work done by the magnetic field extending through the region in which the transition spread accounts roughly for the observed difference

Predictable self-assembled [2×2] Ln(III)4 square grids (Ln = Dy,Tb)-SMM behaviour in a new lanthanide cluster motif.

Science.gov (United States)

Anwar, Muhammad Usman; Thompson, Laurence Kenneth; Dawe, Louise Nicole; Habib, Fatemah; Murugesu, Muralee

2012-05-14

The ditopic carbohydrazone ligand (L1) produces the square, self-assembled [2×2] grids [Dy(4)(L1)(4)(OH)(4)]Cl(2) (1) and [Ln(4)(L1)(4)(μ(4)-O)(μ(2)-1,1-N(3))(4)] (Ln = Dy (2), Tb (3)), with 2 exhibiting SMM behaviour. Two relaxation processes occur with U(eff) = 51 K, 91 K in the absence of an external field, and one with U(eff) = 270 K in the presence of a 1600 Oe optimum field. This journal is © The Royal Society of Chemistry 2012

94 β-Decay Half-Lives of Neutron-Rich _{55}Cs to _{67}Ho: Experimental Feedback and Evaluation of the r-Process Rare-Earth Peak Formation.

Science.gov (United States)

Wu, J; Nishimura, S; Lorusso, G; Möller, P; Ideguchi, E; Regan, P-H; Simpson, G S; Söderström, P-A; Walker, P M; Watanabe, H; Xu, Z Y; Baba, H; Browne, F; Daido, R; Doornenbal, P; Fang, Y F; Gey, G; Isobe, T; Lee, P S; Liu, J J; Li, Z; Korkulu, Z; Patel, Z; Phong, V; Rice, S; Sakurai, H; Sinclair, L; Sumikama, T; Tanaka, M; Yagi, A; Ye, Y L; Yokoyama, R; Zhang, G X; Alharbi, T; Aoi, N; Bello Garrote, F L; Benzoni, G; Bruce, A M; Carroll, R J; Chae, K Y; Dombradi, Z; Estrade, A; Gottardo, A; Griffin, C J; Kanaoka, H; Kojouharov, I; Kondev, F G; Kubono, S; Kurz, N; Kuti, I; Lalkovski, S; Lane, G J; Lee, E J; Lokotko, T; Lotay, G; Moon, C-B; Nishibata, H; Nishizuka, I; Nita, C R; Odahara, A; Podolyák, Zs; Roberts, O J; Schaffner, H; Shand, C; Taprogge, J; Terashima, S; Vajta, Z; Yoshida, S

2017-02-17

The β-decay half-lives of 94 neutron-rich nuclei ^{144-151}Cs, ^{146-154}Ba, ^{148-156}La, ^{150-158}Ce, ^{153-160}Pr, ^{156-162}Nd, ^{159-163}Pm, ^{160-166}Sm, ^{161-168}Eu, ^{165-170}Gd, ^{166-172}Tb, ^{169-173}Dy, ^{172-175}Ho, and two isomeric states ^{174m}Er, ^{172m}Dy were measured at the Radioactive Isotope Beam Factory, providing a new experimental basis to test theoretical models. Strikingly large drops of β-decay half-lives are observed at neutron-number N=97 for _{58}Ce, _{59}Pr, _{60}Nd, and _{62}Sm, and N=105 for _{63}Eu, _{64}Gd, _{65}Tb, and _{66}Dy. Features in the data mirror the interplay between pairing effects and microscopic structure. r-process network calculations performed for a range of mass models and astrophysical conditions show that the 57 half-lives measured for the first time play an important role in shaping the abundance pattern of rare-earth elements in the solar system.

Yb3+ can be much better than Dy3+: SMM properties and controllable self-assembly of novel lanthanide 3,5-dinitrobenzoate-acetylacetonate complexes.

Science.gov (United States)

Gavrikov, Andrey V; Efimov, Nikolay N; Ilyukhin, Andrey B; Dobrokhotova, Zhanna V; Novotortsev, Vladimir M

2018-05-01

The first representatives of the binuclear lanthanide 3,5-dinitrobenzoate-acetylacetonate complexes, namely isostructural compounds [Ln(dnbz)(acac)2(H2O)(EtOH)]2 (Ln = Eu (1), Gd (2), Tb (3), Dy (4), Ho (5), Er (6), Tm (7), and Yb (8); dnbz - 3,5-dinitrobenzoate anion; acac - acetylacetonate (pentane-2,4-dionate) anion) were prepared and characterized. The SMM behavior of the Yb compound 8 was shown to be surprisingly less sensitive to the composition of the Yb3+ coordination environment in comparison with that of the Dy derivative. For Yb compound 8, the anisotropy barrier is Δeff/kB = 26 K under the dc field of 2000 Oe. This value is the highest one currently known for binuclear Yb complexes.

A family of rare-earth-based single chain magnets: playing with anisotropy.

Science.gov (United States)

Bernot, Kevin; Bogani, Lapo; Caneschi, Andrea; Gatteschi, Dante; Sessoli, Roberta

2006-06-21

The first family of rare-earth-based single chain magnets is presented. Compounds of general formula [M(hfac)3(NITPhOPh)], where M = Eu, Gd, Tb, Dy, Ho, Er, or Yb, and PhOPh is the nitronyl-nitroxide radical (2,4'-benzoxo-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide), have been structurally characterized and found to be isostructural. The characterization of both static and dynamic magnetic properties of the whole family is reported. Dy, Tb, and Ho compounds display slow relaxation of the magnetization, and ac susceptibility shows a thermally activated regime with energy barriers of 69, 45, and 34 K for Dy, Tb, and Ho compounds, respectively, while only a frequency-dependent susceptibility is observed for Er below 2.0 K. In Gd and Yb derivatives, antiferromagnetic interactions dominate. The pre-exponential factors differ by about 4 orders of magnitude. Finite size effects, due to naturally occurring defects, affect the static and dynamic properties of the compounds differently.

Ferromagnetic and paramagnetic magnetization of implanted GaN:Ho,Tb,Sm,Tm films

Energy Technology Data Exchange (ETDEWEB)

Maryško, M., E-mail: marysko@fzu.cz; Hejtmánek, J.; Laguta, V. [Institute of Physics of ASCR v.v.i., Cukrovarnická 10, 162 00 Prague 6 (Czech Republic); Sofer, Z.; Sedmidubský, D.; Šimek, P.; Veselý, M. [Department of Inorganic Chemistry, Institute of Chemical Technology, 166 28 Prague 6 (Czech Republic); Mikulics, M. [Peter Grünberg Institut, PGI-9, Forschung Centrum, Jülich D-52425 (Germany); JARA, Fundamentals of Future Information Technology, D52425 Jülich (Germany); Buchal, C. [Peter Grünberg Institut, PGI-9, Forschung Centrum, Jülich D-52425 (Germany); Macková, A.; Malínský, P. [Nuclear Physics Institute of the ASCR v.v.i., 250 68 Řež (Czech Republic); Department of Physics, Faculty of Science, J.E.Purkinje University, České mládeže, 400 96 Ústí nad Labem (Czech Republic); Wilhelm, R. A. [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, Dresden (Germany); Technische Universität Dresden, 01062 Dresden (Germany)

2015-05-07

The SQUID magnetic measurements were performed on the GaN films prepared by metal-organic vapour phase epitaxy and implanted by Tb{sup 3+}, Tm{sup 3+}, Sm{sup 3+}, and Ho{sup 3+} ions. The sapphire substrate was checked by the electron paramagnetic resonance method which showed a content of Cr{sup 3+} and Fe{sup 3+} impurities. The samples 5 × 5 mm{sup 2} were positioned in the classical straws and within an estimated accuracy of 10{sup −6 }emu, no ferromagnetic moment was detected in the temperature region of 2–300 K. The paramagnetic magnetization was studied for parallel and perpendicular orientation. In the case of GaN:Tb sample, at T = 2 K, a pronounced anisotropy with the easy axis perpendicular to the film was observed which can be explained by the lowest quasi-doublet state of the non-Kramers Tb{sup 3+} ion. The Weiss temperature deduced from the susceptibility data using the Curie-Weiss (C-W) law was found to depend substantially on the magnetic field.

Fiber-optic thermometer application of thermal radiation from rare-earth end-doped SiO2 fiber

International Nuclear Information System (INIS)

Katsumata, Toru; Morita, Kentaro; Komuro, Shuji; Aizawa, Hiroaki

2014-01-01

Visible light thermal radiation from SiO 2 glass doped with Y, La, Ce, Pr, Nd, Eu, Tb, Dy, Ho, Er, Tm, Yb, and Lu were studied for the fiber-optic thermometer application based on the temperature dependence of thermal radiation. Thermal radiations according to Planck's law of radiation are observed from the SiO 2 fibers doped with Y, La, Ce, Pr, Eu, Tb, and Lu at the temperature above 1100 K. Thermal radiations due to f-f transitions of rare-earth ions are observed from the SiO 2 fibers doped with Nd, Dy, Ho, Er, Tm, and Yb at the temperature above 900 K. Peak intensities of thermal radiations from rare-earth doped SiO 2 fibers increase sensitively with temperature. Thermal activation energies of thermal radiations by f-f transitions seen in Nd, Dy, Ho, Er, Tm, and Yb doped SiO 2 fibers are smaller than those from SiO 2 fibers doped with Y, La, Ce, Pr, Eu, Tb, and Lu. Thermal radiation due to highly efficient f-f transitions in Nd, Dy, Ho, Er, Tm, and Yb ions emits more easily than usual thermal radiation process. Thermal radiations from rare-earth doped SiO 2 are potentially applicable for the fiber-optic thermometry above 900 K

Crystal structure and Mössbauer studies of the isotypic Fe6-cluster compounds RE15[Fe8C25], RE=Dy, Ho

KAUST Repository

Davaasuren, Bambar

2015-05-01

The carboferrates RE15[Fe8C25] (RE=Dy, Ho) were prepared from mixtures of the elements by arc-melting followed with subsequent annealing at 1373 K. The crystal structures were determined from single crystal X-ray diffraction data and revealed an isotypic relationship to Er15[Fe8C25] (hP48, P321). The main feature of the crystal structure is given by Fe6 cluster units characterized by covalent Fe-Fe bonding interactions. 57Fe Mössbauer spectra of Dy15[Fe8C25] were fitted by three subspectra with relative spectral weights of about 3:3:2 which is in general agreement with the crystal structure. Below 50 K, an onset of magnetic hyperfine fields at the three iron sites is observed which is supposed to be caused by dipolar fields arising from neighboring, slowly relaxing Dy magnetic moments.

Effect of Al-R (R = Dy or Tb) master alloys addition on the properties of magnets made of Nd14.7R1.3Fe75Co2B7

International Nuclear Information System (INIS)

Savchenko, A.G.; Ryazantsev, V.A.; Skuratovskij, Yu.E.; Lileev, A.S.; Menushenkov, V.P.

2000-01-01

The hysteresis characteristics of caked constant magnets of the (Nd, R)-(Fe, Co)-B system alloys with the Al-R master easily-melting additions, wherein R is Dy or Tb, are studied. High efficiency of the mixture method by obtaining highly-coercive constant magnets on the basis of the studied systems alloys is shown. The hysteresis properties of the caked constant magnets may be changed within sufficiently wide limits by varing the number and composition of the alloys mixture components. The effect of the Al-Dy and Al-Tb additions on properties of constant magnets of uniform nominal composition is compared. Higher efficiency of master alloys on the Tb basis is noted; the coercive force and energy characteristics of this series of caked constant magnets is higher [ru

Measurement of formation cross sections of short-lived nuclei by 14 MeV neutron. Nd, Sm, Dy, Er, Yb

Energy Technology Data Exchange (ETDEWEB)

Sakane, H.; Yamamoto, H.; Kawade, K. [Nagoya Univ. (Japan). School of Engineering; Iida, T.; Takahashi, A.

1997-03-01

Eight neutron activation cross sections producing the nuclei with half-lives between 3 min and 24 min were obtained at the energy range between 13.4 and 14.9 MeV by activation method. The cross sections were {sup 146}Nd(n,p){sup 146}Pr, {sup 154}Sm(n,{alpha}){sup 151}Nd, {sup 162}Dy(n,p){sup 162}Tb, {sup 163}Dy(n,np){sup 162}Tb, {sup 163}Dy(n,p){sup 163}Tb, {sup 164}Dy(n,p){sup 164}Tb, {sup 170}Er(n,{alpha}){sup 167}Dy, {sup 174}Yb(n,p){sup 170}Tm. {sup 163}Dy(n,np){sup 162}Tb (T{sub 1/2}=7.7 min) was obtained for the first time. Present results are compared with previous results and the evaluated data of JENDL-3 and ENDF/B-VI. There are some discrepancies between present results and the JENDL-3 and ENDF/B-VI. (author)

Microstructural, magnetic and magnetostrictive properties of Tb0.3Dy0.7Fe1.95 prepared by solidification in a high magnetic field

International Nuclear Information System (INIS)

Liu Tie; Liu Yin; Wang Qiang; Gao Pengfei; He Jicheng; Iwai, Kazuhiko

2013-01-01

The microstructure evolution and magnetization and magnetostriction properties of Tb 0.3 Dy 0.7 Fe 1.95 alloy solidified in a high magnetic field were investigated. A cellular microstructure was produced, with the grains highly aligned along the direction of the magnetic field. The (Tb,Dy)Fe 2 phase was highly oriented, with its 〈1 1 1〉 axis along the magnetic field direction. The easy magnetization direction of the alloy lay along the magnetic field direction. The magnetostriction at room temperature significantly increased to double that of the sample prepared without high magnetic field; in addition, a sharp rise in the initial magnetostriction at low fields was observed. Applying a high magnetic field during the solidification process is proposed as an effective route for fabricating 〈1 1 1〉 oriented Tb–Dy–Fe compounds, and improving their magnetic and magnetostrictive properties. (paper)

Search for excited superdeformed bands in {sup 151}Dy

Energy Technology Data Exchange (ETDEWEB)

Nisius, D.; Janssens, R.V.F.; Crowell, B. [and others

1995-08-01

Following the first report of superdeformed (SD) bands with identical transition energies in the pairs ({sup 151}Tb*,{sup 152}Dy), ({sup 150}Gd*, {sup 151}Tb) and ({sup 153}Dy*, {sup 152}Dy) (where * denotes an excited SD band), it was proposed by Nazarewicz et al. that the observations could be understood in a strong-coupling approach if pseudo SU(3) symmetry were invoked. In this model there are three limiting values of the decoupling parameter; i.e. a = 0, {plus_minus}1. In the first two cases mentioned above the pairs of bands have nearly identical transition energies and are interpreted as proton excitations involving the [200]1/2 pseudospin orbital coupled to the {sup 152}Dy core, for which the value of the decoupling parameter is calculated to be a =+1.

Study of X-ray L2 absorption edges of Gd, Dy, Ho and Er in metals and compounds

International Nuclear Information System (INIS)

Agarwal, B.K.; Agarwal, B.R.K.

1978-01-01

The positions and shapes of L2 X-ray absorption edges of Gd, Dy, Ho and Er have been studied in metals and in oxides and chlorides, using a forty centimetre bent mica crystal spectrograph. It has been found that the L2 edge shifts towards the high energy side in the compounds and that the chemical shift ΔE depends on the degree of covalency involved. The white line structure at the edge has been analysed in terms of transitions of L2 shell electron to optical nd (n >= 5) states. (author)

Crystalline electric field at the rare-earth sites in RxY1-xCo5+y compounds (R= Dy and Tb)

International Nuclear Information System (INIS)

Han Xiufeng; Jin Hanmin; Chen Hong; Guo Guanghua; Zhao Tiesong

1992-01-01

The magnetic properties of R x Y 1-x Co 5+y compounds are reproduced well by a calculation based on the single-ion model. The values of the exchange field H cx and crystalline-electric-field parameters A m n at the rare-earth ion sites in R x Y 1-x Co 5+y (R = Dy and Tb) are evaluated by fitting the calculations to the experiments. The experiments include the temperature dependence of the spontaneous magnetization, the temperature dependence of the normalized magnetic moments of the rare-earth ions, the temperature dependence of the cone angle, the magnetization curves along the crystal axes at 4.2 K, and the hyperfine field at the Dy ion site

Magnesium-rich intermetallics RE3RuMg7 (RE = Y, Nd, Dy, Ho). Rows of condensed Ru rate at RE6/2 octahedra in magnesium matrices

International Nuclear Information System (INIS)

Kersting, Marcel; Rodewald, Ute C.; Schwickert, Christian; Poettgen, Rainer

2013-01-01

The magnesium-rich intermetallic phases RE 3 RuMg 7 (RE = Y, Nd, Dy, Ho) have been synthesized from the elements in sealed niobium ampoules and subsequently characterized by powder X-ray diffraction. The structure of the dysprosium compound was refined on the basis of single-crystal X-ray diffractometer data: Ti 6 Sn 5 type, P6 3 /mmc, a = 1019.1(2), c = 606.76(9) pm, wR2 = 0.0159, 439 F 2 values, 19 variables. The Mg3 site shows a small degree of Mg3/Dy mixing, leading to the composition Dy 3.03 RuMg 6.97 for the investigated crystal. The striking structural motifs in the Dy 3 RuMg 7 structure are rows of face-sharing Ru rate at Dy 6 octahedra and corner-sharing Mg2 rate at Mg 8 Dy 4 icosahedra. The rows of octahedra form a hexagonal rod-packing, and each rod is enrolled by six rows of the condensed icosahedra. Temperature-dependent magnetic susceptibility measurements of Dy 3 RuMg 7 show Curie-Weiss behavior with an experimental magnetic moment of 10.66(1) μ B per Dy atom. Antiferromagnetic ordering is detected at T N = 27.5(5) K. The 5 K isotherm shows a metamagnetic transition at a critical field of H C = 40 kOe. (orig.)

Dielectric measurements of magnetic monopoles on the spin-ice compounds (Ho/Dy){sub 2}Ti{sub 2}O{sub 7}

Energy Technology Data Exchange (ETDEWEB)

Pietsch, Manuel; Grams, Christoph P.; Welter, Jean-Francois; Cho, Victoria; Lorenz, Thomas; Hemberger, Joachim [II. Physikalisches Institut, Universitaet zu Koeln, Cologne (Germany)

2015-07-01

In so-called spin-ice compounds a frustrated ground-state with finite zero-point entropy is stabilized via competing interactions and emergent magnetic monopoles excitations. It was postulated that a magnetic monopole holds an electric dipole moment, which allows to investigate their dynamics via the dielectric function ε(ν). In Dy{sub 2}Ti{sub 2}O{sub 7} a critical speeding-up for frequencies up to 100 kHz was reported down to temperatures of 200 mK with a specific focus on the critical endpoint present for a [111] magnetic field. In Ho{sub 2}Ti{sub 2}O{sub 7} both faster relaxation dynamics compared to the sister-compound and an additional relaxation process are suspected. Here we report on broadband dielectric spectroscopy measurements of ε(ν) in Ho{sub 2}Ti{sub 2}O{sub 7}.

Chemical Bond Parameters in Sr3MRhO6 (M=Rare earth)

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

Chemical bond parameters, that is, bond covalency, bond valence, macroscopic linear susceptibility, and oxidation states of elements in Sr3MRhO6 (M=Sm, Eu, Tb, Dy, Ho, Er, Yb) have been calculated. The results indicate that the bond covalency of M-O decreases sharply with the decrease of ionic radius of M3+ from Sm to Yb, while no obvious trend has been found for Rh-O and Sr-O bonds. The global instability index indicates that the crystal structures of Sr3MrhO6 (M = Sm, Eu, Tb, Dy, Ho) have strained bonds.

Stability constants and thermodynamic parameters of trivalent gadolinium, yttrium, terbium, dysprosium and holmium complexes with 2-(p-sulphophenylazo) 1,8-dihydroxynaphthalene 3,6 disulphonic acid (trisodium salt)[SPADNS

International Nuclear Information System (INIS)

Dubey, S.N.; Nagpal, S.; Kalra, H.L.; Puri, D.M.

1980-01-01

The stepwise stability constants of Gd(III), Y(III), Tb(III), Dy(III) and Ho(III) complexes with SPADNS have been determined potentiometrically in aqueous solution using Bjerrum-Calvin technique as modified by Irving and Rossotti at different temperatures (20deg and 40deg) and 0.1 M ionic strength (NaClO 4 ). The trend in the stability of these metal complexes has been found to be: Ho(III) > Dy(III) > Tb(III) > Y(III) > Gd(III). The overall changes in ΔGdeg, ΔHdeg and ΔSdeg accompanying the complex formation have also been determined. (author)

Stability constants and thermodynamic parameters of trivalent gadolinium, yttrium, terbium, dysprosium and holmium complexes with 2-(p-sulphophenylazo) 1,8-dihydroxynaphthalene 3,6 disulphonic acid (trisodium salt)(SPADNS)

Energy Technology Data Exchange (ETDEWEB)

Dubey, S.N.; Nagpal, S.; Kalra, H.L.; Puri, D.M. (Kurukshetra Univ. (India). Dept. of Chemistry)

1980-10-01

The stepwise stability constants of Gd(III), Y(III), Tb(III), Dy(III) and Ho(III) complexes with SPADNS have been determined potentiometrically in aqueous solution using Bjerrum-Calvin technique as modified by Irving and Rossotti at different temperatures (20deg and 40deg) and 0.1 M ionic strength (NaClO/sub 4/). The trend in the stability of these metal complexes has been found to be: Ho(III) > Dy(III) > Tb(III) > Y(III) > Gd(III). The overall changes in ..delta..Gdeg, ..delta..Hdeg and ..delta..Sdeg accompanying the complex formation have also been determined.

Investigation of chemical bond characteristics, thermal expansion coefficients and bulk moduli of alpha-R2MoO6 and R2Mo2O7 (R = rare earths) by using a dielectric chemical bond method.

Science.gov (United States)

Li, Huaiyong; Zhang, Siyuan; Zhou, Shihong; Cao, Xueqiang

2009-09-01

Theoretical researches are performed on the alpha-R2MoO6 (R = Y, Gd, Tb Dy, Ho, Er, Tm and Yb) and pyrochlore-type R2Mo2O7 (R = Y, Nd, Sm, Gd, Tb and Dy) rare earth molybdates by using chemical bond theory of dielectric description. The chemical bonding characteristics and their relationship with thermal expansion property and compressibility are explored. The calculated values of linear thermal expansion coefficient (LTEC) and bulk modulus agree well with the available experimental values. The calculations reveal that the LTECs and the bulk moduli do have linear relationship with the ionic radii of the lanthanides: the LTEC decreases from 6.80 to 6.62 10(-6)/K and the bulk modulus increases from 141 to 154 GPa when R goes in the order Gd, Tb Dy, Ho, Er, Tm, and Yb in the alpha-R2MoO6 series; while in the R2Mo2O7 series, the LTEC ranges from 6.80 to 6.61 10(-6)/K and the bulk modulus ranges from 147 to 163 GPa when R varies in the order Nd, Sm, Gd, Tb and Dy. Copyright 2008 Wiley Periodicals, Inc.

Ternary germanides RERhGe{sub 2} (RE = Y, Gd-Ho) – New representatives of the YIrGe{sub 2} type

Energy Technology Data Exchange (ETDEWEB)

Voßwinkel, Daniel; Heletta, Lukas; Hoffmann, Rolf-Dieter; Pöttgen, Rainer, E-mail: pottgen@uni-muenster.de

2016-11-15

The YIrGe{sub 2} type ternary germanides RERhGe{sub 2} (RE = Y, Gd-Ho) were synthesized from the elements by arc-melting and characterized by powder X-ray diffraction. The structure of DyRhGe{sub 2} was refined from single crystal X-ray diffractometer data: Immm, a = 426.49(9), b = 885.0(2), c = 1577.4(3) pm, wR2 = 0.0533, 637 F{sup 2} values, 30 variables (300 K data). The structure contains two crystallographically independent dysprosium atoms in pentagonal prismatic and hexagonal prismatic coordination. The three-dimensional [RhGe{sub 2}] polyanion is stabilized through covalent Rh–Ge (243–261 pm) and Ge–Ge (245–251 pm) bonding. The close structural relationship with the slightly rhodium-poorer germanides RE{sub 5}Rh{sub 4}Ge{sub 10} (≡ RERh{sub 0.8}Ge{sub 2}) is discussed. Temperature-dependent magnetic susceptibility measurements reveal Pauli paramagnetism for YRhGe{sub 2} and Curie-Weiss paramagnetism for RERhGe{sub 2} with RE = Gd, Tb, Dy and Ho. These germanides order antiferromagnetically at T{sub N} = 7.2(5), 10.6(5), 8.1(5), and 6.4(5) K, respectively. - Graphical abstract: The germanides RERhGe{sub 2} (RE = Y, Gd-Ho) are new representatives of the YIrGe{sub 2} type.

Sol-gel syntheses of pentaborate β-LaB5O9 and the photoluminescence by doping with Eu3+, Tb3+, Ce3+, Sm3+, and Dy3+

Science.gov (United States)

Yang, Ruirui; Sun, Xiaorui; Jiang, Pengfei; Gao, Wenliang; Cong, Rihong; Yang, Tao

2018-02-01

Rare earth (RE) borates have been extensively studied as good photoluminescent materials, however, the target hosts were limited to "RE3BO6", REBO3, and REB3O6 in the RE2O3-B2O3 phase diagram until the recent discovery of rare earth pentaborate. For the first time, the sol-gel method was employed to synthesize β-LaB5O9 doped with Eu3+, Tb3+, Ce3+, Sm3+, Dy3+. In comparison to the previous synthetic methods, the sol-gel method possesses superiorities including easily-controllable doping concentration, high yield and emission efficiency. Solid solutions of phosphors were prepared and carefully analyzed by powder X-ray diffraction. Concentration quenching or saturation was observed in Eu3+, Tb3+ and Ce3+ doped phosphors at round 10 at%. Eu3+, Tb3+, Sm3+, and Dy3+ emit red, green, orange, and close-to-white light, respectively. The absolute emission efficiency of Ce3+ is high and in the UV range, suggesting the function of being sensitizer once combined with other activators.

Development of separation process of Dy, Y, Tm and Yb from heavier rare earth residue by solvent impregnated resin

International Nuclear Information System (INIS)

Shibata, J.; Matsumoto, S.

1998-01-01

Full text: Heavier rare earth which is contained in a small amount in ores such as bastnesite and monazite has been accumulated as heavier rare earth residue without doing separation and purification due to lack of suitable methods. The heavier rare earth residue includes seven rare earth elements such as Tb, Dy, Ho, Y, Er, Tm and Yb. Separation and recovery process of Dy, Y, Tm and Yb from leached solution of the heavier rare earth residue was investigated by using a column method with a solvent impregnated resin. The solvent impregnated resin was prepared by impregnation of organophosphorous extractant whose trade name is PC-88A into a macro porous resin, Amberlite XAD-7. It was almost impossible to separate them in simple adsorption and elution steps. However, we attained to individually separate Dy, Y, Tm and Yb from the leached solution first by changing eluent concentration gradually from pH 2 to 2mol/ l HCl in the elution step, and secondly by using a development column and changing eluent concentration in the elution step. The separation process flow was proposed for heavier rare earth residue by using the solvent impregnated resin method

Studies on the preparation of ferric-hydroxide macro aggregate and hydroxyapatite particles labelled with Sm-153, Ho-166 and/or Dy-165 for radiation synovectomy

International Nuclear Information System (INIS)

Le Van So; Pham Ngoc Dien; Truong Hong Nghia; Nguyen Thi Thu; Nguyen Cong Duc; Vo Thji Cam Hoa; Bui Van Cuong

2004-01-01

The modified methods for the preparation of Hydroxyapatite particle (HA) and Ferric Hydroxide Macro Aggregated (FHMA of high stability and uniformity in particle size and of good geometrical shape suitable for production of radiolabeled carrier for radiation synovectomy purpose were developed. 165 Dy, 166 Ho and/or 153 Sm labeled HA and FHMA were produced using a simple labelling method. (author)

Structural, spectral, dielectric and magnetic properties of Tb–Dy doped Li-Ni nano-ferrites synthesized via micro-emulsion route

Energy Technology Data Exchange (ETDEWEB)

Junaid, Muhammad, E-mail: junaid.malik95@yahoo.com [Department of Physics, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Khan, Muhammad Azhar, E-mail: azhar.khan@iub.edu.pk [Department of Physics, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Iqbal, F. [Department of Physics, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Murtaza, Ghulam [Centre for Advanced Studies in Physics, Government College University, Lahore 54000 (Pakistan); Akhtar, Majid Niaz; Ahmad, Mukhtar [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Shakir, Imran [Deanship of scientific research, College of Engineering, King Saud University, PO Box 800, Riyadh 11421 (Saudi Arabia); Warsi, Muhammad Farooq [Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan)

2016-12-01

Terbium (Tb) and dysprosium (Dy) doped lithium-nickel nano-sized ferrites (Li{sub 0.2}Ni{sub 0.8}Tb{sub 0.5x}Dy{sub 0.5x}Fe{sub 2−x}O{sub 4} where x=0.00−0.08) were prepared by micro-emulsion technique. The X-ray diffraction (XRD) patterns confirmed the single phase cubic spinel structure. The lattice constant was increased due to larger ionic radii of Tb{sup 3+} and Dy{sup 3+} cations. The crystallite size was found in the range 30–42 nm. The FTIR (Fourier transform infrared spectroscopy) spectra revealed two significant absorption bands (~400–600 cm{sup −1}) which indicate the formation of cubic spinel structure. The peaking behavior of dielectric parameters was observed beyond 1.5 GHz. The dielectric constant and dielectric loss were found to decrease by the increase of Tb–Dy contents and frequency. The doping of Tb and Dy in Li–Ni ferrites led to increase the coercive field (120–156 Oe). The smaller magnetic and dielectric parameters suggested the possible utility of these nano-materials in switching and microwave devices applications. - Highlights: • Li{sub 0.2}Ni{sub 0.8}Tb{sub 0.5x}Dy{sub 0.5x}Fe{sub 2-x}O{sub 4} ferrites were synthesized by micro-emulsion route. • Tb and Dy addition improves coercivity while decreased saturation magnetization. • These nanomaterials can be useful in microwave and switching devices applications.

Nuclear spectroscopy of very proton rich nuclei through HI induced reactions; the 14s high spin isomer in /sup 95/Pd

CERN Document Server

Nolte, E; Geier, R; Gui, S Z; Heim, U; Hick, H; Komninos, P; Korschinek, G; Kubik, P; Morinaga, H; Schollmeier, W

1981-01-01

/sup 40/Ca, /sup 58/Ni and /sup 60/Ni beams from the Munich tandem and the Munich heavy ion postaccelerator have been used to produce very proton rich nuclei in the N=50 N=82 regions. The residual nuclei have been studied with the help of gamma and particle spectroscopy. The level schemes of /sup 95/Rh, /sup 146/Dy and /sup 150/Er and the beta -decay schemes, /sup 95/Pd/sup m/ to /sup 95/Rh, /sup 144/Tb to /sup 144/Gd, /sup 146/Ho to /sup 146/Dy to /sup 146/Tb to /sup 146/Gd, /sup 148/Er to /sup 148/Ho to /sup 148/Dy and /sup 150/Tm to /sup 150/Er to /sup 150/Dy have been investigated. beta delayed proton emission from a J/sup pi / approximately=21/sup +/ isomeric state in /sup 95/Pd has been observed. (12 refs).

Neutron-scattering study of the magnetic structure of DyFe₄Al₈ and HoFe₄Al₈

DEFF Research Database (Denmark)

Paixao, J.A.; Silva, M.R.; Sørensen, S.Aa.

2000-01-01

The magnetic structures of DyFe4Al8 and HoFe4Al8, which have been reported to be unusual spin-glass systems, were studied in detail by neutron diffraction, using both unpolarized and polarized beams. In fact these compounds have long-range magnetic order in both the Fe and rare-earth sublattices....

Direct measurements of conventional and anisotropic magnetocaloric effect in binary RAl2 single crystals

Science.gov (United States)

Monteiro, J. C. B.; Gandra, F. G.

2017-06-01

We report on specific heat and magnetocaloric effect (MCE) measurements in single crystals of HoAl2, DyAl2, and TbAl2 measured by a heat flux technique using Peltier devices. Those compounds order ferromagnetically at 31 K, 61 K, and 106 K respectively, and present a spin reorientation transition (SRT) below TC. We study the dependence of the SRT with magnetic field and temperature by means of specific heat measurements performed in single crystals oriented at the [" separators="| 100 ], [" separators="| 110 ], and [" separators="| 111 ] directions with the aid of calculations using a simple model. We obtained the conventional MCE for HoAl2 and TbAl2 and also the anisotropic version of the effect obtained indirectly from the specific heat for TbAl2 and DyAl2. We also present the results for a direct determination of the anisotropic MCE for DyAl2 by measuring the heat flux generated by a rotation of the single crystal under constant field.

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)

Morphology and luminescence characteristics of combustion synthesized Y{sub 2}O{sub 3}: (Eu, Dy, Tb) nanoparticles with various amino-acid fuels

Energy Technology Data Exchange (ETDEWEB)

Mukherjee, S.; Sudarsan, V. [Chemistry Division Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Sastry, P.U.; Patra, A.K. [Solid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Tyagi, A.K., E-mail: aktyagi@barc.gov.in [Chemistry Division Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

2014-01-15

Y{sub 2}O{sub 3} nanoparticles doped with Dy{sup 3+}, Eu{sup 3+} and Tb{sup 3+} together were prepared by the gel combustion method using a variety of amino acids namely, glycine, phenyl alanine, arginine, glutamic and aspartic acids. Number of carboxylate groups present in the amino acids used for combustion reaction was found to have strong influence on powder characteristics as well as luminescence from the samples. Based on small angle X-ray scattering studies, it is inferred that the nanoparticles prepared by using glycine and arginine as the fuels have smooth surface compared to those prepared using other amino acids. For the nanoparticles prepared using glutamic and aspartic acids, there exist a diffused pore-grain interface due to the lesser extent of heat generated in the reaction which leads to smaller particle size, poor crystallinity and improper burning of the organic materials. Lower surface area and smooth surface of the nanoparticles prepared using glycine leads to their improved luminescence properties. -- Highlights: • Surface smoothness of Y{sub 2}O{sub 3} (Dy, Eu, Tb) nanoparticles vary with amino acids. • Optimum luminescence intensity is observed when glycine is used as the fuel. • Diffused pore grain interface when glutamic and aspartic acids are used as fuels.

Synthesis, characterization, and in vitro evaluation of a radio-metal organic framework composed of in vivo generator {sup 166}Dy/{sup 166}Ho and DOTMP as a novel agent for bone marrow ablation

Energy Technology Data Exchange (ETDEWEB)

Vosoghi, Sara; Shirvani-Arani, Simindokht; Bahrami-Samani, Ali; Salek, Nafise; Mirerezaei, Ehsan; Jalilian, Amir Reza [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of)

2016-07-01

In this study, the MOF concept contributed to the preparation of a novel, bone-ablating agent composed of Cu(II) using the in vivo generator {sup 166}Dy/{sup 166}Ho and 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene phosphonic acid (DOTMP). The product was characterized (IR, elemental analysis: CHN, ICM-MS, PIXE, DLS, XRD) and quality-controlled (radio-thin layer chromatography (RTLC)). The stability and in vitro hydroxyapatite binding was checked up to one week at 37 C in human serum. Radio-MOF crystals and colloidal radio-MOF particles were obtained by varying the synthesizing conditions (including pH and temperature), and they had similar IR patterns and similar elemental analysis results. The estimated chemical formula was [1Lu-1Cu-1Cl-1DOTMP] for both. The final product was synthesized at pH = 8 while stirring at room temperature using {sup 166}Dy/{sup 166}Ho-nitrate, CuCl{sub 2}, and DOTMP (yield > 99%, RTLC). Dynamic light scattering (DLS) measurements showed particles in the size range of 60 to 100 nm for the resultant radio-MOF particles (RMP). In vitro binding experiments showed acceptable bone-seeking affinity of the prepared formula even after one week of storage in human serum at 37 C. Importantly, this is the first study of the use of the MOF concept to provide a highly-stable organometallic compound containing {sup 166}Dy/{sup 166}Ho in vivo generator for bone marrow ablation.

Completing the series. New coordination networks of composition {sup 3}{sub ∞}[RE{sub 2}(ADC){sub 3}(H{sub 2}O){sub 6}].2H{sub 2}O with RE = Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Y and ADC{sup 2-} = acetylenedicarboxylate ({sup -}O{sub 2}C-C≡C-CO{sub 2}{sup -})

Energy Technology Data Exchange (ETDEWEB)

Gramm, Verena K.; Schuy, Andrea; Ruschewitz, Uwe [Institut fuer Anorganische Chemie, Koeln Univ. (Germany); Suta, Markus; Wickleder, Claudia [Anorganische Chemie, Universitaet Siegen (Germany); Sternemann, Christian [Fakultaet Physik / DELTA, Technische Universitaet Dortmund (Germany)

2018-02-01

The crystal structures of {sup 3}{sub ∞}[RE{sub 2}(ADC){sub 3}(H{sub 2}O){sub 6}].2H{sub 2}O (RE = Pr, Nd, Sm, Eu, Tb, Dy) were solved and refined from X-ray single crystal data. They crystallize in a structure type already known for RE = La, Ce and Gd (P1, no. 2, Z = 2), which is characterized by REO{sub 9} polyhedra forming dimeric units being the nodes of a 3D framework structure linked by ADC{sup 2-} anions ({sup -}O{sub 2}C-C≡C-CO{sub 2}{sup -} = acetylenedicarboxylate). From synchrotron powder diffraction data it was shown that isostructural coordination networks are formed for RE = Ho, Er, Y, whereas for RE = Tm, Yb, Lu a new structure type crystallizing in a highly complex crystal structure with a large orthorhombic unit cell is found. All compounds are obtained by slow evaporation of an aqueous solution containing RE(OAc){sub 3}.xH{sub 2}O and acetylenedicarboxylic acid (H{sub 2}ADC). The coordination networks of composition {sup 3}{sub ∞}[RE{sub 2}(ADC){sub 3}(H{sub 2}O){sub 6}].2H{sub 2}O were thoroughly investigated by thermal analysis and for RE = Eu, Tb, a strong red and green photoluminescence was observed and investigated by means of UV/Vis spectroscopy. (copyright 2018 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Simulation of the magnetocaloric effect in Tb nanofilms

Energy Technology Data Exchange (ETDEWEB)

Anselmo, Dory Hélio A. L., E-mail: doryh@dfte.ufrn.br [Departamento de Física Teórica e Experimental (DFTE), Universidade Federal do Rio Grande do Norte (UFRN), Natal-RN (Brazil); Mello, Vamberto D. [Departamento de Física,Universidade do Estado do Rio Grande do Norte (UERN), Mossoró-RN (Brazil); Vasconcelos, Manoel S. [Escola de Ciência e Tecnologia (ECT), Universidade Federal do Rio Grande do Norte (UFRN), Natal-RN (Brazil)

2014-03-31

Rare-earth (RE) metals have different magnetic structures resulting from the competition between the crystal-field and exchange interactions. When a magnetic field is applied it creates a third interaction and the magnetic structures are more complicated. In thin films, it is expected that even the magnetic arrangement itself can be strongly modified. Rare-earth helimagnets such as Terbium (Tb), Holmium (Ho) and Dysprosium (Dy) represent the best candidates to evidence such finite-size effects. This finite-size effect is caused by the reduced number of atoms in the direction perpendicular to the film plane that leads to a decrease of the total magnetic exchange energy. We report this contribution to the investigation of magnetocaloric effect (MCE) of thin Terbium films in the helimagnetic temperature range, from T{sub C} = 219 K to T{sub N} = 231 K, for external fields of the order of 1 kOe. We find that for strong fields, H = 50 kOe, the adiabatic temperature change ΔT near the Néel temperature is around 15 K for any thickness of Tb films. However large thickness effects are found for small values of the magnetic field. For field strength of the order of a few kOe, the thermocaloric efficiency increases significantly for ultrathin (nanomagnetic) films.

Crystallization and magnetic characterizations of DyIG and HoIG nanopowders fabricated using citrate sol-gel

Directory of Open Access Journals (Sweden)

Dao Thi Thuy Nguyet

2016-06-01

Full Text Available Dy and Ho iron garnets in form of nanoparticles were synthesized by citrate sol-gel method. Phase formation, lattice constant and average crystallite sizes of the samples were determined via XRD measurements. Morphology and particle size distribution were studied by TEM and chemical composition was checked by EDX. Magnetic measurements in temperature range 5–600 K and in the maximum applied field of 50 kOe were carried out by using SQUID and VSM. Their magnetic parameters, including Curie temperature, magnetization compensation temperature, spontaneous magnetization, high-field susceptibility, magnetic coercivity were discussed in the framework of three interacting magnetic sublattices, magnetocrystalline anisotropy, core-shell model and compared to those of the bulk materials. Based on these analyses further evaluation on the crystallinity and homogeneity of the samples has been made.

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.

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.

The quantitative analysis of 163Ho source by PIXE

International Nuclear Information System (INIS)

Sera, K.; Ishii, K.; Fujioka, M.; Izawa, G.; Omori, T.

1984-01-01

We have been studying the electron-capture in 163 Ho as a method for determining the mass of electron neutrino. The 163 Ho sources were produced with the 164 Dy(p,2n) reaction by means of a method of internal irradiation 2 ). We applied the PIXE method to determine the total number of 163 Ho atoms in the source. Proton beams of 3 MeV and a method of ''external standard'' were employed for nondestructive analysis of the 163 Ho source as well as an additional method of ''internal standard''. (author)

First Penning-trap mass measurement of the electron capture nuclide {sup 163}Ho and its daughter {sup 163}Dy for the ECHO project

Energy Technology Data Exchange (ETDEWEB)

Schneider, Fabian [Institut fuer Kernchemie und Institut fuer Physik, Johannes Gutenberg-Universitaet Mainz (Germany); Collaboration: TRIGA-SPEC Collaboration; ECHo-Collaboration

2015-07-01

The ECHo (Electron Capture of {sup 163}Ho) project aims to determine the mass of the electron neutrino by measuring the calorimetric spectrum of {sup 163}Ho. To be able to extract the neutrino mass from the spectrum near the endpoint a precise knowledge of the decay Q-value is necessary. The ideal way to measure this in a model independent way is by high-precision Penning-trap mass spectrometry. The ECHo collaboration has {sup 163}Ho samples available, which were produced by reactor neutron irradiation. Such samples are typically highly contaminated with radioactive and stable species. These were efficiently removed by chemical purification. Ionization by laser ablation allows high-precision Penning-trap mass measurements with sample sizes of 10{sup 16} atoms. From the measured cyclotron frequency ratio of {sup 163}Ho{sup 16}O{sup +} to {sup 163}Dy{sup 16}O{sup +} we determined the Q-value to be 2.5(7) keV. In addition absolute mass measurements using carbon cluster ions as reference were performed with an uncertainty two times lower than literature values. Future measurements at SHIPTRAP (GSI, Darmstadt) and PENTATRAP (MPIK, Heidelberg) are planned with the aim to drastically improve the uncertainty of the Q-value down to a few eV and thus providing the required input for the ECHo project.

On 165Ho level scheme

International Nuclear Information System (INIS)

Ardisson, Claire; Ardisson, Gerard.

1976-01-01

A 165 Ho level scheme was constructed which led to the interpretation of sixty γ rays belonging to the decay of 165 Dy. A new 702.9keV level was identified to be the 5/2 - member of the 1/2 ) 7541{ Nilsson orbit. )] [fr

Magnetic order of Y{sub 3}NiSi{sub 3}-type R{sub 3}NiSi{sub 3} (R=Gd–DY) compounds

Energy Technology Data Exchange (ETDEWEB)

Morozkin, A.V., E-mail: morozkin@tech.chem.msu.ru [Department of Chemistry, Moscow State University, Leninskie Gory, House 1, Building 3, GSP-2, Moscow 119992 (Russian Federation); Yapaskurt, V.O. [Department of Petrology, Faculty of Geology, Moscow State University, Leninskie Gory, Moscow 119992 (Russian Federation); Nirmala, R. [Indian Institute of Technology Madras, Chennai 600036 (India); Malik, S.K.; Quezado, S. [Departamento de Física Teórica e Experimental, Universidade Federal do Rio Grande do Norte, Natal 59082-970 (Brazil); Yao, Jinlei; Mozharivskyj, Y. [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1 (Canada); Nigam, A.K. [Tata Institute of Fundamental Research, Mumbai 400005 (India); Isnard, O. [Université Grenoble Alpes, Inst NEEL, BP166, F-38042 Grenoble (France); CNRS, Institut NEEL, 25 rue des martyrs, F-38042 Grenoble (France)

2016-01-15

Magnetic measurements and neutron powder diffraction investigations on the Y{sub 3}NiSi{sub 3}-type R{sub 3}NiSi{sub 3} compounds (R=Gd, Tb, Dy) reveal their complex antiferromagnetic ordering. Magnetic measurements on Gd{sub 3}NiSi{sub 3}, Tb{sub 3}NiSi{sub 3} and Dy{sub 3}NiSi{sub 3} indicate antiferromagnetic-like transition at temperatures 260 K, 202 K and 140 K, respectively. Also, the Tb{sub 3}NiSi{sub 3} and Dy{sub 3}NiSi{sub 3} compounds show spin-reorientation transition at 132 K and 99 K, respectively. Below the spin-reorientation transition, the isothermal magnetization curves indicate the metamagnetic-like behavior of Tb{sub 3}NiSi{sub 3} and Dy{sub 3}NiSi{sub 3}. The magnetocaloric effect of Dy{sub 3}NiSi{sub 3} is calculated in terms of isothermal magnetic entropy change and it reaches a maximum value of −1.2 J/kg K and −1.1 J/kg K for a field change of 50 kOe near 146 K and 92 K, respectively. The neutron diffraction studies of Tb{sub 3}NiSi{sub 3} suggest the magnetic ordering of the Tb2 4j sublattice and no magnetic ordering of the Tb1 2a sublattice. Tb{sub 3}NiSi{sub 3} transforms from the high temperature paramagnetic state to the commensurate high-temperature a- and c-axis antiferromagnet of I′2/m magnetic space group below 250 K. Below 150 K, the high-temperature antiferromagnet transforms into the low-temperature a-, b- and c-axis antiferromagnet of I′i magnetic space group. At 1.5 K, the terbium magnetic moment in Tb2 sublattice and its a-, b- and c-axis components reach the values of M{sub Tb2}=8.2(1) μ{sub B}, M{sub aTb2}=5.9(1) μ{sub B}, M{sub bTb2}=4.3(2) μ{sub B} and M{sub cTb2}=3.7(2) μ{sub B}, respectively. - Highlights: • Gd{sub 3}NiSi{sub 3}, Tb{sub 3}NiSi{sub 3} and Dy{sub 3}NiSi{sub 3} have Neel points of 260. 202 and 140 K. • Tb{sub 3}NiSi{sub 3} and Dy{sub 3}NiSi{sub 3} show spin-reorientation transition at 132 and 99 K. • Tb{sub 3}NiSi{sub 3} exhibits the commensurate magnetic ordering of Tb2 4j sublattice

Neutron activation analysis of NBS oyster tissue (SRM 1566) and IAEA animal bone (H-5)

International Nuclear Information System (INIS)

Lepel, E.A.; Laul, J.C.

1983-10-01

Data have been presented for 35 elements determined by INAA for NBS oyster tissue (SRM 1566) and for 38 elements determined by INAA and RNAA for IAEA animal bone (H-5). The experimental data showed excellent agreement with published values wherever the comparison exists. Additional trace-element data in the ppb range have been presented for the elements Sc, Sb, Cs, La, Ce, Nd, Sm, Eu, Tb, Dy, Ho, Yb, Lu, Hf, Ta, W and Th in NBS oyster tissue. Also, additional trace-element data for IAEA animal bone (H-5) in the ppb range for the elements Al, Sc, Co, Rb, Cs, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb, lu, Hf, Ta and Th have been presented

Transition rates in {sup 161}Dy

Energy Technology Data Exchange (ETDEWEB)

Berg, V; Malmskog, S G

1969-06-15

The decay of {sup 161}Tb has been studied using a high resolution Ge(Li)-detector. Five new transitions were observed and fitted into the earlier proposed decay scheme. The half-life of the 131.8 keV level in {sup 161}Dy was determined in a delayed coincidence measurement to be 145 {+-} 15 psec. The low level scheme in {sup 161}Dy is discussed within a quasi-particle model allowing for Coriolis mixing. Special attention is given to the strongly retarded, K-allowed 131.8 keV E1 transition with a retardation factor F{sub W} > 1.5 x 10{sup 8}.

Isothermal sections of phase equilibria diagrams for systems (terbium, dysprosium, holmium)-molybdenum-boron at 1273 K

International Nuclear Information System (INIS)

Kuz'ma, Yu.B.; Zakharchuk, N.P.; Maksimova, L.T.

1988-01-01

The methods of X-ray analysis are used to study the R-Mo-B (R-Tb, Dy, Ho) systems and isothermal sections of phase equilibria diagrams at 1273 K are plotted. A formation of RMoB 4 (structure of the YCrB 4 type) is confirmed and borides R 3 MoB 7 (structure of the Er 3 CrB 7 type) and ∼ RMo 4 B 8 (of the unknown structure) are obtained for the first time. Borides DyMoB 3 and HoMoB 3 are of the ErMoB 3 structure. Lattice periods of new compounds are indicated. Diffractogrammes of borides Dy 3 MoB 7 and DyMoB 3 are calculated. A peculiarity of components interaction in the systems rare-earth metal-molybdenum-boron is considered

Neutron scattering studies of the coexistence of long-range magnetic order and superconductivity in Dy12Mo6S8 and Tb12Mo6S8

International Nuclear Information System (INIS)

Thomlinson, W.; Shirane, G.; Moncton, D.E.; Ishikawa, M.; Fischer, O.

1978-10-01

Both Dy 1 2 Mo 6 S 8 and Tb 1 2 Mo 6 S 8 are superconducting below T/sub c/ = 2.05 K. Neutron scattering studies show that these compounds in zero applied magnetic field develop long-range antiferromagnetic order (greater than 300 A) at T/sub M/ = 0.4 K and T/sub M/ = 1.0 K, respectively, which does not destroy the superconducting state. Magnetization measurements at temperatures below T/sub M/ suggest the development of ferromagnetic order as the applied magnetic field increases. In the case of Tb 1 2 Mo 6 S 8 the neutron data show long-range ferromagnetic order developing for H greater than or equal to H/sub c2/ = 1.9 kOe where H/sub c2/ is the upper critical field for superconductivity. However, for Dy 1 2 Mo 6 S 8 long-range ferromagnetic order begins to develop at H = 200 Oe, a field much less than H/sub c2/ = 1.2 kOe. As the ferromagnetic intensity increases, the antiferromagnetic intensity decreases. Between H = 200 Oe and H = 1.2 kOe both ferromagnetic and antiferromagnetic order occur with the sample in the superconducting state

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

Series of edge-sharing bi-triangle Ln4 clusters with a μ4-NO3- bridge: syntheses, structures, luminescence, and the SMM behavior of the Dy4 analogue.

Science.gov (United States)

Zou, Hua-Hong; Wang, Rong; Chen, Zi-Lu; Liu, Dong-Cheng; Liang, Fu-Pei

2014-02-14

A series of Ln4 clusters, [Ln4L2(μ3-OH)2(μ4-NO3)(NO3)4(OCH3)(H2O)]·xMeCN·yMeOH (Ln = Gd (1), Tb (2), Dy (3), Ho (4), Er (5), Yb (6), L = 2-{[2-(2-hydroxy-ethoxy)-ethylimino]-methyl}-6-methoxyphenol), have been synthesized by the reaction of Ln(NO)3 and a Schiff-base ligand formed in situ. The six complexes display similar structures, with an overall metal core comprising two edge-sharing triangular Ln3 units linked by a μ4-NO3(-) bridge. The luminescence spectrum of complex 2 shows the characteristic emission of the Tb(III) ions. The magnetic susceptibility studies reveal that the Ln(III) ions are very weakly interacting in all six compounds. Frequency dependence of the ac-susceptibility was found for 3, suggesting a typical single-molecule magnet (SMM) behavior with an anisotropic barrier of 28 K.

Rhombus-shaped tetranuclear [Ln4] complexes [Ln = Dy(III) and Ho(III)]: synthesis, structure, and SMM behavior.

Science.gov (United States)

Chandrasekhar, Vadapalli; Hossain, Sakiat; Das, Sourav; Biswas, Sourav; Sutter, Jean-Pascal

2013-06-03

The reaction of a new hexadentate Schiff base hydrazide ligand (LH3) with rare earth(III) chloride salts in the presence of triethylamine as the base afforded two planar tetranuclear neutral complexes: [{(LH)2Dy4}(μ2-O)4](H2O)8·2CH3OH·8H2O (1) and [{(LH)2Ho4}(μ2-O)4](H2O)8·6CH3OH·4H2O (2). These neutral complexes possess a structure in which all of the lanthanide ions and the donor atoms of the ligand remain in a perfect plane. Each doubly deprotonated ligand holds two Ln(III) ions in its two distinct chelating coordination pockets to form [LH(Ln)2](4+) units. Two such units are connected by four [μ2-O](2-) ligands to form a planar tetranuclear assembly with an Ln(III)4 core that possesses a rhombus-shaped structure. Detailed static and dynamic magnetic analysis of 1 and 2 revealed single-molecule magnet (SMM) behavior for complex 1. A peculiar feature of the χM" versus temperature curve is that two peaks that are frequency-dependent are revealed, indicating the occurrence of two relaxation processes that lead to two energy barriers (16.8 and 54.2 K) and time constants (τ0 = 1.4 × 10(-6) s, τ0 = 7.2 × 10(-7) s). This was related to the presence of two distinct geometrical sites for Dy(III) in complex 1.

Interaction of xenone difluoride with the fluorocomplexes of lanthanides and rubidium of the Rb3M3F6 composition

International Nuclear Information System (INIS)

Goryachenkov, S.A.; Fadeeva, N.E.; Kiselev, Yu.M.; Martynenko, L.I.; Spitsyn, V.I.

1984-01-01

The possibility of preparing rubidium fluorocomplexes of tetravalent lanthanides of the Rb 3 M 4 F 7 composition from Rb 3 M 3 F 6 (M 3 =Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb) with XeF 2 has been studied. By the DTA method it is shown that Ce and Pr salts are fluorinated respectively at approximately 100 and approximately 235 deg C with a noticeable exoeffect. Tb and Dy salts fluorination proceeds with considerable kinetic difficulties. The fluorination products composition, Rb 3 M 4 F 7 (M 4 =Ce, Pr, Tb, Dy) is confirmed by the methods of chemical, IR-spectroscopic and X-ray phase analyses. XeF 2 interaction with Rb 3 M 3 F 6 salts of other lanthanides up to 400 deg C has not been observed

Muzeum módy - Tokyo 2010

OpenAIRE

Kráľová, Zuzana

2010-01-01

navrhovaný objekt je múzeum módy pre mesto Tokio. Múzeum sa bude nachádzať na pulzujúcej tepne tokijského módneho diania. Navrhovaná budova presahuje 100m výšky a jej zbierky mapujú vývoj svetovej módy 20.storčia. Taktiež je dejiskom konania živých módnych show a priestorom pre prezentáciu tvorby mladých módnych tvorcov. Samotné artefakty zbierky sú vystavované jednotným systémom - zavesením. visiace figuríny prechádzajú kontinuálne celým výstavným priestorom, návštevníkovi je umožnený pohyb ...

The Ho–Ni–Ge system: Isothermal section and new rare-earth nickel germanides

Energy Technology Data Exchange (ETDEWEB)

Morozkin, A.V., E-mail: morozkin@tech.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, Faculty of Geology, 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 L8S 4M1 (Canada); Pani, M.; Provino, A.; Manfrinetti, P. [Institute SPIN-CNR and Dipartimento di Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, 16146 Genova (Italy)

2015-05-15

The Ho–Ni–Ge system has been investigated at 1070 K and up to ~60 at% Ho by X-ray diffraction and microprobe analyses. Besides the eight known compounds, HoNi{sub 5}Ge{sub 3} (YNi{sub 5}Si{sub 3}-type), HoNi{sub 2}Ge{sub 2} (CeAl{sub 2}Ga{sub 2}-type), Ho{sub 2}NiGe{sub 6} (Ce{sub 2}CuGe{sub 6}-type), HoNiGe{sub 3} (SmNiGe{sub 3}-type), HoNi{sub 0.2÷0.6}Ge{sub 2} (CeNiSi{sub 2}-type), Ho{sub 37÷34}Ni{sub 6÷24}Ge{sub 57÷42} (AlB{sub 2}-type), HoNiGe (TiNiSi-type), Ho{sub 3}NiGe{sub 2} (La{sub 3}NiGe{sub 2}-type), the ternary system contains four new compounds: Ho{sub 3}Ni{sub 11}Ge{sub 4} (Sc{sub 3}Ni{sub 11}Ge{sub 4}-type), HoNi{sub 3}Ge{sub 2} (ErNi{sub 3}Ge{sub 2}-type), Ho{sub 3}Ni{sub 2}Ge{sub 3} (Hf{sub 3}Ni{sub 2}Si{sub 3}-type) and ~Ho{sub 5}Ni{sub 2}Ge{sub 3} (unknown structure). Quasi-binary solid solutions were observed at 1070 K for Ho{sub 2}Ni{sub 17}, HoNi{sub 5}, HoNi{sub 7}, HoNi{sub 3}, HoNi{sub 2}, HoNi and Ho{sub 2}Ge{sub 3}, but no detectable solubility was found for the other binary compounds in the Ho–Ni–Ge system. Based on the magnetization measurements, the HoNi{sub 5}Ge{sub 3}, HoNi{sub 3}Ge{sub 2} and Ho{sub 3}Ni{sub 11}Ge{sub 4} (and isostructural (Tb, Dy){sub 3}Ni{sub 11}Ge{sub 4}) compounds have been found to show paramagnetic behavior down to 5 K, whereas Ho{sub 3}Ni{sub 2}Ge{sub 3} exhibits an antiferromagnetic transition at ~7 K. Additionally, the crystal structure of the new isostructural phases (Y, Yb)Ni{sub 3}Ge{sub 2} (ErNi{sub 3}Ge{sub 2}-type), Er{sub 3}Ni{sub 11}Ge{sub 4} (Sc{sub 3}Ni{sub 11}Ge{sub 4}-type) and (Y, Tb, Dy, Er, Tm){sub 3}Ni{sub 2}Ge{sub 3} (Hf{sub 3}Ni{sub 2}Si{sub 3}-type) has been also investigated. - Graphical abstract: The Ho–Ni–Ge system has been investigated at 1070 K and up to ~60 at.% Ho by X-ray and microprobe analyses. Besides the eight known compounds, i.e. HoNi{sub 5}Ge{sub 3} (YNi{sub 5}Si{sub 3}-type), HoNi{sub 2}Ge{sub 2} (CeAl{sub 2}Ga{sub 2}-type), Ho{sub 2}NiGe{sub 6} (Ce{sub 2

Room temperature synthesis of hydrophilic Ln(3+)-doped KGdF4 (Ln = Ce, Eu, Tb, Dy) nanoparticles with controllable size: energy transfer, size-dependent and color-tunable luminescence properties.

Science.gov (United States)

Yang, Dongmei; Li, Guogang; Kang, Xiaojiao; Cheng, Ziyong; Ma, Ping'an; Peng, Chong; Lian, Hongzhou; Li, Chunxia; Lin, Jun

2012-06-07

In this paper, we demonstrate a simple, template-free, reproducible and one-step synthesis of hydrophilic KGdF(4): Ln(3+) (Ln = Ce, Eu, Tb and Dy) nanoparticles (NPs) via a solution-based route at room temperature. X-Ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) and cathodoluminescence (CL) spectra are used to characterize the samples. The results indicate that the use of water-diethyleneglycol (DEG) solvent mixture as the reaction medium not only allows facile particle size control but also endows the as-prepared samples with good water-solubility. In particular, the mean size of NPs is monotonously reduced with the increase of DEG content, from 215 to 40 nm. The luminescence intensity and absolute quantum yields for KGdF(4): Ce(3+), Tb(3+) NPs increase remarkably with particle sizes ranging from 40 to 215 nm. Additionally, we systematically investigate the magnetic and luminescence properties of KGdF(4): Ln(3+) (Ln = Ce, Eu, Tb and Dy) NPs. They display paramagnetic and superparamagnetic properties with mass magnetic susceptibility values of 1.03 × 10(-4) emu g(-1)·Oe and 3.09 × 10(-3) emu g(-1)·Oe at 300 K and 2 K, respectively, and multicolor emissions due to the energy transfer (ET) process Ce(3+)→ Gd(3+)→ (Gd(3+))(n)→ Ln(3+), in which Gd(3+) ions play an intermediate role in this process. Representatively, it is shown that the energy transfer from Ce(3+) to Tb(3+) occurs mainly via the dipole-quadrupole interaction by comparison of the theoretical calculation and experimental results. This kind of magnetic/luminescent dual-function materials may have promising applications in multiple biolabels and MR imaging.

Ln3+ (Ln=Ce, Tb, Dy) and Hf doping of LuI3 powders – A material and spectroscopic study

International Nuclear Information System (INIS)

Wiatrowska, Aneta; Keur, Wilco; Ronda, Cees

2016-01-01

The moisture sensitivity of LuI 3 :Ce,Hf and luminescent properties of undoped LuI 3 and LuI 3 :M (M=Ce 3+ , Tb 3+ , Dy 3+ ) powders were investigated. The possibility of improving the air and moisture stability of LuI 3 :Ce by Hf doping was tested. It was proven that the Hf contribution to the LuI 3 :Ce stability is very limited and is insignificant to render LuI 3 :Ce scintillator powders suitable for applications. Photoluminescence results of LuI 3 without dopants added on purpose showed luminescence due to a plurality of rare-earth elements' impurities. Two types of self-trapped luminescence were found. Energy transfer between host lattice, self-trapped excitons and rare-earth ions was investigated.

Production of 149Tb in deep inelastic transfer reactions: an approach to the angular momentum of fragments

International Nuclear Information System (INIS)

Rivet, M.F.; Bimbot, R.; Gardes, D.; Fleury, A.; Hubert, F.; Llabador, Y.

1978-01-01

The excitation functions for deep inelastic reactions in which two to six charges are transferred from 40 Ar and 63 Cu ions to rare earth targets have been measured using activation techniques, the observed radionuclides being 150 Dy, 151 Dy and 149 gTb. From the comparison of the curves relative to 149 gTb and those relative to 150 Dy, 151 Dy, it was deduced that the low spin isomer 149 gTb was produced with significant probability for low incident energies. Using data from (heavy ions, xn) reactions, it was possible to attribute this production to the deexcitation of Tb fragments formed in deep inelastic transfers with angular momenta lower than 9n. This result is in good agreement with the angular momentum calculations performed under the hypothesis that the initial angular momentum window leading to deep inelastic reactions is situated between the critical angular momentum for fusion and that corresponding to grazing collisions. As far as Cu induced reactions are concerned, both hypothesis of rolling and sticking are consistent with the experimental data. For Ar induced reactions, the results indicate that the stage of sticking is not reached when the incident energy is lower than 200 MeV

Studies on the decay of 160Tb to levels in 160Dy by Ge (Li)-Ge(Li)-coincidence system

International Nuclear Information System (INIS)

Hassan, A.M.; Abou-Zeid, M.A.; Mekamer, M.

1981-01-01

This work concerned with the study of the energy levels and the properties of gamma-ray transitions in 160 Dy resulting from the B-decay of the parent radioactive isotope 160 Tb (72 d.). These studies have been done by means of, single and gamma-gamma coincidence measurements. Log(ft). Internal Conversion Coefficient (ICC) values and the branching ratios have been calculated. The construction and testes of the Ge(Li)-Ge(Li) gamma-gamma coincidence spectrometer are presented. In addition to the previously reported transitions in three new transitions of energies 203, 420 and 1048 keV have been observed for the first time. The energy level at 1288.60 keV is confirmed, due to the presence of the 246 keV and 1005 keV gamma-ray transitions in the singles and gamma-gamma coincidence spectra. Furthermore the B-intensity feeding this level was calculated for the first time to be 0.08%. The log(ft) values of the energy level at 1288.6 keV was calculated for the first time to be 10.79. The energy level diagram of 160 Dy as summerised in the present work consists of 12 excited states, the levels at 581(6 + ) and 1391 keV reported by some authors were not encluded, since no transitions populated or depopulated these levels could be observed

Local rhombohedral symmetry in Tb0.3Dy0.7Fe2 near the morphotropic phase boundary

International Nuclear Information System (INIS)

Ma, Tianyu; Liu, Xiaolian; Pan, Xingwen; Li, Xiang; Jiang, Yinzhu; Yan, Mi; Li, Huiying; Fang, Minxia; Ren, Xiaobing

2014-01-01

The recently reported morphotropic phase boundary (MPB) in a number of giant magnetostrictive materials (GMMs) has drawn considerable interest to the local symmetry/structure near MPB region of these materials. In this letter, by in-situ X-ray diffraction and AC magnetic susceptibility measurements, we show that Tb 0.3 Dy 0.7 Fe 2 , the typical composition of Terfenol-D GMMs, has coexistence of rhombohedral and tetragonal phases over a wide temperature range in the vicinity of MPB. High resolution transmission electron microscopy provides direct evidence for local rhombohedral symmetry of the ferromagnetic phase and reveals regular-shaped nanoscale domains below 10 nm. The nano-sized structural/magnetic domains are hierarchically inside a single micron-sized stripe-like domain with the same average magnetization direction. Such domain structures are consistent with the low magnetocrystalline anisotropy and easy magnetic/structural domain switching under magnetic field, thus generating large magnetostriction at low field

Fine Structure in Proton Emission from the Deformed 141g.sHo and 141mHo

International Nuclear Information System (INIS)

Karny, M.; Rykaczewski, Krzysztof Piotr; Grzywacz, R.; Batchelder, J.C.; Bingham, C.R.; Goodin, C. T.; Gross, Carl J.; Hamilton, J.H.; Korgul, A.; Krolas, W.; Liddick, S. N.; Li, K.; Maier, Karl; Mazzocchi, C.; Piechaczek, A.; Shapira, Dan; Simpson, D.; Tantawy, M.N.; Winger, J.A.; Yu, Chang-Hong; Zganjar, E. F.

2007-01-01

Fine structure in proton emission from the deformed states 141g.s Ho (T 1/2 = 4.1 ms) and 141 mHo (T 1/2 = 7.4 (micro)s) has been discovered at Oak Ridge by detecting fusion evaporation residues with the Recoil Mass Spectrometer, Si-detectors and digital signal processing electronics. The branching ratios to the first 2 + excited state in 140 Dy were measured to be I p g.s. (2 + ) = 0.9±0.1% and I p m (2 + ) = 1.7±0.5%. A comparison of the available calculations to the experimental values calls for further development of the theoretical models

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.

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)

Hydrothermal synthesis, structure, and optical properties of two nanosized Ln{sub 26} rate at CO{sub 3} (Ln=Dy and Tb) cluster-based lanthanide-transition-metal-organic frameworks (Ln MOFs)

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yu; Huang, Lian; Miao, Hao; Wan, Hong Xiang; Mei, Hua; Liu, Ying [State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University (China); Xu, Yan [State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University (China); State Key Laboratory of Coordination Chemistry, Nanjing Tech University (China)

2015-02-16

Two Ln{sub 26} rate at CO{sub 3} (Ln=Dy and Tb) cluster-based lanthanide-transition-metal-organic frameworks (Ln MOFs) formulated as [Dy{sub 26}Cu{sub 3}(Nic){sub 24}(CH{sub 3}COO){sub 8}(CO{sub 3}){sub 11}(OH){sub 26}(H{sub 2}O){sub 14}]Cl . 3 H{sub 2}O (1; HNic=nicotinic acid) and [Tb{sub 26}NaAg{sub 3}(Nic){sub 27}(CH{sub 3}COO){sub 6}(CO{sub 3}){sub 11}(OH){sub 26}Cl(H{sub 2}O){sub 15}] . 7.5 H{sub 2}O (2) have been successfully synthesized by hydrothermal methods and characterized by IR, thermogravimetric analysis (TGA), elemental analysis, and single X-ray diffraction. Compound 1 crystallizes in the monoclinic space group Cc with a=35.775(12) Aa, b=33.346(11) Aa, c=24.424(8) Aa, β=93.993(5) , V=29065(16) Aa{sup 3}, whereas 2 crystallizes in the triclinic space group P anti 1 with a=20.4929(19) Aa, b=24.671(2) Aa, c=29.727(3) Aa, α=81.9990(10) , β=88.0830(10) , γ=89.9940(10) , V=14875(2) Aa{sup 3}. Structural analysis indicates the framework of 1 is a 3D perovskite-like structure constructed out of CO{sub 3} rate at Dy{sub 26} building units and Cu{sup +} centers by means of nicotinic acid ligand bridging. In 2, however, nanosized CO{sub 3} rate at Tb{sub 26} units and [Ag{sub 3}Cl]{sup 2+} centers are connected by Nic{sup -} bridges to give rise to a 2D structure. It is worth mentioning that this kind of 4d-4f cluster-based MOF is quite rare as most of the reported analogous compounds are 3d-4f ones. Additionally, the solid-state emission spectra of pure compound 2 at room temperature suggest an efficient energy transfer from the ligand Nic{sup -} to Tb{sup 3+} ions, which we called the ''antenna effect''. Compound 2 shows a good two-photon absorption (TPA) with a TPA coefficient of 0.06947 cm GM{sup -1} (1 GM = 10{sup -50} cm{sup 4} s photon{sup -1}), which indicates that compound 2 might be a good choice for third-order nonlinear optical materials. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Extraordinarily large intrinsic magnetodielectric coupling of the Tb member within the Haldane spin-chain family R2BaNiO5

Science.gov (United States)

Upadhyay, Sanjay Kumar; Paulose, P. L.; Sampathkumaran, E. V.

2017-07-01

The Haldane spin-chain compound Tb2BaNiO5 has been known to order antiferromagnetically below (TN= )63 K . The present magnetic studies on the polycrystals bring out that there is another magnetic transition at a lower temperature (T2=)25 K with pronounced magnetic-field-induced metamagnetic and metaelectric behaviors. Multiferroic features are found below T2 only and not at TN. The most intriguing observation is that the observed change in dielectric constant (Δɛ') is intrinsic and largest (e.g., ˜18% at 15 K) within this Haldane spin-chain family R2BaNiO5 . Taking into account the fact that this trend (that is, the largest value of Δɛ' for the Tb case within this family) correlates well with a similar trend in TN (with the values of TN being ˜55, 58, 53, and 32 K for Gd, Dy, Ho, and Er cases), we believe that the explanation usually offered for this TN behavior in rare-earth systems is applicable for this Δɛ' behavior as well. That is, single-ion anisotropy following crystal-field splitting is responsible for the extraordinary magnetodielectric effect in this Tb case. This work provides a pathway in the field of multiferroics to promote magnetoelectric coupling.

Magnetostriction-strain-induced enhancement and modulation of photovoltaic performance in Si-p-n/TbxDy1-xFe2 composite

International Nuclear Information System (INIS)

Wu, Zheng; Zhang, Yihe; Fang, Cong; Ma, Ke; Lin, He; Jia, Yanmin; Chen, Jianrong; Wang, Yu; Chan, Helen Lai Wa

2014-01-01

High photovoltaic efficiency is a key index in the application of silicon (Si) solar cells. In this study, a composite of a photovoltaic Si p-n junction solar cell and a magnetostrictive Tb x Dy 1-x Fe 2 alloy was fabricated. By utilizing the magnetostrictive strain to modulate the energy bandgap of Si, the open-circuit voltage and the maximum photovoltaic output power of the Si p-n junction solar cell could be enhanced by ∝12% and 9.1% under a dc magnetic field of ∝250 mT, respectively. The significantly enhanced photovoltaic performance and the simple fabrication process make the Si-p-n/Tb x Dy 1-x Fe 2 composite a promising material for high-efficiency solar cell devices. The structure of the proposed Si-p-n/Tb x Dy 1-x Fe 2 laminated composite. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Photoluminescence of trivalent rare earths in perovskite stacking polytypes Ba/sub 2/Lasub(2-x)REsub(x)/sup 3 +/MgW/sub 2/vacantO/sub 12/, Ba/sub 6/Ysub(2-x)REsub(x)/sup 3 +/W/sub 3/vacantO/sub 18/, and Sr/sub 8/SrGdsub(2-x)REsub(x)/sup 3 +/W/sub 4/vacantO/sub 24/

Energy Technology Data Exchange (ETDEWEB)

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

1981-12-01

Rhombohedral 12 L staking polytypes Ba/sub 2/Lasub(2-x)REsub(x)/sup 3 +/MgW/sub 2/vacantO/sub 12/ show with RE/sup 3 +/ = Pr, Sm, Eu, Tb, Dy, Ho, Er, Tm; the 18 L stacking polytypes Ba/sub 6/Ysub(2-x)REsub(x)/sup 3 +/W/sub 3/vacantO/sub 18/ and the polymorphic perovskites Sr/sub 8/SrGdsub(2-x)REsub(x)/sup 3 +/W/sub 4/vacantO/sub 24/ with RE/sup 3 +/ = Sm, Eu, Dy, Ho, Er visible photoluminescence. The concentration dependence and the influence of the coordination number of the rare earth are reported.

Luminescence and magnetic behaviour of almond like (Na0.5La0.5)MoO4:RE3+ (RE = Eu, Tb, Dy) nanostructures

International Nuclear Information System (INIS)

Krishnan, Rajagopalan; Thirumalai, Jagannathan; Thomas, Sabu; Gowri, Mahasampath

2014-01-01

Graphical abstract: Monodispersed almond-like (Na 0.5 La 0.5 )MoO 4 :RE 3+ nanostructures synthesized by employing ethylene-diamine tetra acetic acid (EDTA) using hydrothermal route at 200 °C for 24 h. These nanoparticles were found to be novel bi-functional candidates suitable for high-quality luminescence and magnetic applications. - Highlights: • Almond like structures of (Na 0.5 La 0.5 )MoO 4 :RE 3+ were synthesized by hydrothermal method. • Time dependent self-assembly could be the dominant process for the formation of 3D networks. • Luminescence properties of nanosamples were studied in comparison with bulk sample. • Room temperature magnetic properties of bulk and nanophosphors were investigated. - Abstract: Tetragonal phase (Na 0.5 La 0.5 )MoO 4 :RE 3+ (RE = Eu, Tb, Dy) with almond like hierarchical structures assembled from nanosheets building blocks were successfully synthesized by employing disodium ethylenediaminetetraacetic acid (Na 2 EDTA) using hydrothermal route at 200 °C for 24 h. Field emission scanning electron microscope, transmission electron microscope, and X-ray diffraction patterns were used to characterize the morphology, size, and crystal structure with good resolution. The sequestering agent EDTA acts as quadridentate ligand coordinated with metal ions [Na + , La 3+ /RE 3+ ] facilitating the formation of self-organized 3D networks. The growth mechanism for the formation of almond like nanostructures is explicated in four paths: dissolution, adsorption, in situ transformation in acidic and basic media and the effective collision. Photoluminescence excitation and emission spectra reveals a spectral blue shift which was observed in the nanosamples towards shorter wavelengths compared with the bulk sample. Upon UV irradiation, both bulk and nanostructure show strong luminescence in the red region due to the 5 D 0 → 7 F 2 transition in Eu 3+ . Also, Tb 3+ and Dy 3+ doped (Na 0.5 La 0.5 )MoO 4 phosphor exhibit green and yellow

Antiferromagnetic domains in rare earth metals and alloys

Energy Technology Data Exchange (ETDEWEB)

Palmer, S B [Hull Univ. (UK). Dept. of Applied Physics

1975-12-01

Anomalies in the c-axis elastic properties of antiferromagnetic Dy, 50% Tb-Ho and 60% Gd-Y are reported. The anomalies are only present when the sample is cycled from the ferromagnetic to the antiferromagnetic state and are attributed to domains in the helical regime.

Determination of Elevator Shaft Uprightness Applying the Terrestrial Laser Scanning Method / Určovanie Zvislosti Výťahovej Šachty Metódou Terestrického Laserového Skenovania

Directory of Open Access Journals (Sweden)

Kovanič Ľudovít

2013-09-01

Full Text Available V príspevku sú prezentované výsledky geodetického merania a spracovania údajov na určenie geometrických parametrov výťahovej šachty použitím klasických a tiež moderných prístupov získavania meraných dát. Zámerom je overenie možnosti využitia terestrického laserového skenovania ako vhodnej, efektívnej a detailnej metódy pre zber priestorových údajov.

Interaction of xenon difluoride with the fluorocomplexes of lanthanides and rubidium of the Rb/sub 3/M/sup 3/F/sub 6/ composition

Energy Technology Data Exchange (ETDEWEB)

Goryachenkov, S.A.; Fadeeva, N.E.; Kiselev, Yu.M.; Martynenko, L.I.; Spitsyn, V.I. (Moskovskij Gosudarstvennyj Univ. (USSR))

The possibility of preparing rubidium fluorocomplexes of tetravalent lanthanides of the Rb/sub 3/M/sup 4/F/sub 7/ composition from Rb/sub 3/M/sup 3/F/sub 6/ (M/sup 3/=Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb) with XeF/sub 2/ has been studied. By the DTA method it is shown that Ce and Pr salts are fluorinated respectively at approximately 100 and approximately 235 deg C with a noticeable exoeffect. Tb and Dy salts fluorination proceeds with considerable kinetic difficulties. The fluorination products composition, Rb/sub 3/M/sup 4/F/sub 7/ (M/sup 4/=Ce, Pr, Tb, Dy) is confirmed by the methods of chemical, IR-spectroscopic and X-ray phase analyses. XeF/sub 2/ interaction with Rb/sub 3/M/sup 3/F/sub 6/ salts of other lanthanides up to 400 deg C has not been observed.

The high-temperature modification of LuAgSn and high-pressure high-temperature experiments on DyAgSn, HoAgSn, and YbAgSn

Energy Technology Data Exchange (ETDEWEB)

Heying, B.; Rodewald, U.C.; Hermes, W.; Schappacher, F.M.; Riecken, J.F.; Poettgen, R. [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Heymann, G.; Huppertz, H. [Muenchen Univ. (Germany). Dept. fuer Chemie und Biochemie; Sebastian, C.P. [Max-Planck-Institut fuer Chemische Physik Fester Stoffe, Dresden (Germany)

2008-02-15

The high-temperature modification of LuAgSn was obtained by arc-melting an equiatomic mixture of the elements followed by quenching the melt on a water-cooled copper crucible. HT-LuAgSn crystallizes with the NdPtSb-type structure, space group P6{sub 3}mc: a = 463.5(1), c = 723.2(1) pm, wR2 = 0.0270, 151 F{sup 2}, and 11 variables. The silver and tin atoms build up two-dimensional, puckered [Ag{sub 3}Sn{sub 3}] networks (276 pm Ag-Sn) that are charge-balanced and separated by the lutetium atoms. The Ag-Sn distances between the [Ag{sub 3}Sn{sub 3}] layers of 294 pm are much longer. Single crystals of isotypic DyAgSn (a = 468.3(1), c = 734.4(1) pm, wR2 = 0.0343, 411 F{sup 2}, and 11 variables) and HoAgSn (a = 467.2(1), c = 731.7(2) pm, wR2 = 0.0318, 330 F{sup 2}, and 11 variables) were obtained from arc-melted samples. Under high-pressure (up to 12.2 GPa) and high-temperature (up to 1470 K) conditions, no transitions to a ZrNiAl-related phase have been observed for DyAgSn, HoAgSn, and YbAgSn. HT-TmAgSn shows Curie-Weiss paramagnetism with {mu}{sub eff} = 7.53(1) {mu}{sub B}/Tm atom and {theta}P = -15.0(5) K. No magnetic ordering was evident down to 3 K. HT-LuAgSn is a Pauli paramagnet. Room-temperature {sup 119}Sn Moessbauer spectra of HT-TmAgSn and HT-LuAgSn show singlet resonances with isomer shifts of 1.78(1) and 1.72(1) mm/s, respectively. (orig.)

Intermediate magnetization state and competing orders in Dy2Ti2O7 and Ho2Ti2O7

Science.gov (United States)

Borzi, R. A.; Gómez Albarracín, F. A.; Rosales, H. D.; Rossini, G. L.; Steppke, A.; Prabhakaran, D.; Mackenzie, A. P.; Cabra, D. C.; Grigera, S. A.

2016-01-01

Among the frustrated magnetic materials, spin-ice stands out as a particularly interesting system. Residual entropy, freezing and glassiness, Kasteleyn transitions and fractionalization of excitations in three dimensions all stem from a simple classical Hamiltonian. But is the usual spin-ice Hamiltonian a correct description of the experimental systems? Here we address this issue by measuring magnetic susceptibility in the two most studied spin-ice compounds, Dy2Ti2O7 and Ho2Ti2O7, using a vector magnet. Using these results, and guided by a theoretical analysis of possible distortions to the pyrochlore lattice, we construct an effective Hamiltonian and explore it using Monte Carlo simulations. We show how this Hamiltonian reproduces the experimental results, including the formation of a phase of intermediate polarization, and gives important information about the possible ground state of real spin-ice systems. Our work suggests an unusual situation in which distortions might contribute to the preservation rather than relief of the effects of frustration. PMID:27558021

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

Carbonato-bridged Ni(II)2Ln(III)2 (Ln(III) = Gd(III), Tb(III), Dy(III)) complexes generated by atmospheric CO2 fixation and their single-molecule-magnet behavior: [(μ4-CO3)2{Ni(II)(3-MeOsaltn)(MeOH or H2O)Ln(III)(NO3)}2]·solvent [3-MeOsaltn = N,N'-bis(3-methoxy-2-oxybenzylidene)-1,3-propanediaminato].

Science.gov (United States)

Sakamoto, Soichiro; Fujinami, Takeshi; Nishi, Koshiro; Matsumoto, Naohide; Mochida, Naotaka; Ishida, Takayuki; Sunatsuki, Yukinari; Re, Nazzareno

2013-06-17

Atmospheric CO2 fixation of [Ni(II)(3-MeOsaltn)(H2O)2]·2.5H2O [3-MeOsaltn = N,N'-bis(3-methoxy-2-oxybenzylidene)-1,3-propanediaminato], Ln(III)(NO3)3·6H2O, and triethylamine occurred in methanol/acetone, giving a first series of carbonato-bridged Ni(II)2Ln(III)2 complexes [(μ4-CO3)2{Ni(II)(3-MeOsaltn)(MeOH)Ln(III)(NO3)}2] (1Gd, 1Tb, and 1Dy). When the reaction was carried out in acetonitrile/water, it gave a second series of complexes [(μ4-CO3)2{Ni(II)(3-MeOsaltn)(H2O)Ln(III)(NO3)}2]·2CH3CN·2H2O (2Gd, 2Tb, and 2Dy). For both series, each Ni(II)2Ln(III)2 structure can be described as two di-μ-phenoxo-bridged Ni(II)Ln(III) binuclear units bridged by two carbonato CO3(2-) units to form a carbonato-bridged (μ4-CO3)2{Ni(II)2Ln(III)2} structure. The high-spin Ni(II) ion has octahedral coordination geometry, and the Ln(III) ion is coordinated by O9 donor atoms from Ni(II)(3-MeOsaltn), bidentate NO3(-), and one and two oxygen atoms of two CO3(2-) ions. The NO3(-) ion for the first series roughly lie on Ln-O(methoxy) bonds and are tilted toward the outside, while for the second series, the two oxygen atoms roughly lie on one of the Ln-O(phenoxy) bonds due to the intramolecular hydrogen bond. The temperature-dependent magnetic susceptibilities indicated a ferromagnetic interaction between the Ni(II) and Ln(III) ions (Ln(III) = Gd(III), Tb(III), Dy(III)) for all of the complexes, with a distinctly different magnetic behavior between the two series in the lowest-temperature region due to the Ln(III)-Ln(III) magnetic interaction and/or different magnetic anisotropies of the Tb(III) or Dy(III) ion. Alternating-current susceptibility measurements under the 0 and 1000 Oe direct-current (dc) bias fields showed no magnetic relaxation for the Ni(II)2Gd(III)2 complexes but exhibited an out-of-phase signal for Ni(II)2Tb(III)2 and Ni(II)2Dy(III)2, indicative of slow relaxation of magnetization. The energy barriers, Δ/kB, for the spin flipping were estimated from the Arrhenius

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).

Determination of the cross section for (n,p) reaction with producing short-lived nuclei on the 162,163Dy isotopes at 13.5 and 14.8 MeV

International Nuclear Information System (INIS)

Luo, Junhua; Feng, Zhifu; An, Li; Jiang, Li; He, Long

2016-01-01

Activation cross-sections for the 162 Dy(n,p) 162 Tb and 163 Dy(n,p) 163 Tb reactions have been measured by means of the activation technique and a coaxial HPGe γ-ray detector at 13.5 and 14.8 MeV. The fast neutrons were produced via the 3 H(d,n) 4 He reaction on Pd-300 neutron generator. The natural high-purity Dy 2 O 3 powder was used as target material. Theoretical excitation functions were calculated using the nuclear-reaction codes EMPIRE-3.2 Malta and TALYS-1.6 with default parameters, at neutron energies varying from the reaction threshold to 20 MeV. The results were also discussed and compared with some corresponding values found in the literature, with the comprehensive evaluation data in ENDF/B-VII.1 and JENDF-4.0 libraries, and with the estimates obtained from a published empirical formula based on the statistical model with Q-value dependence and odd–even effects taken into consideration. - Highlights: • The cross sections for the 162 Dy(n,p) 162 Tb and 163 Dy(n,p) 163 Tb have been measured. • 93 Nb(n,2n) 92m Nb was used as a monitor for neutron fluence. • Codes TALYS-1.6 and EMPIRE-3.2 Malta were used to model the reactions. • The results were compared with previous data. • Inconsistency with previous data and with model calculations are noted.

Influence of Al-atoms on the spin fluctuation scattering in R(Co,Al)2 compounds

International Nuclear Information System (INIS)

Duc, N.H.; Hung, D.T.; Kim-Ngan, N.H.; Sechovsky, V.

1992-01-01

The resistivity and magnetisation have been measured for the R(Co 1-x Al x ) 2 compounds with R=Nd, Gd, Tb, Dy, Ho, Er and Lu. For x=0.2 the resistivity enhancement is observed below T c , however, for the compounds with R=Lu-Tb only. The results are discussed in terms of the spin fluctuation scattering and indicate that the enhancement of the spin fluctuation scattering is strongly related to the lattice parameter. (orig.)

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Preparation and characterization of DLC/SiO2/Al2O3 nanofiltration membrane .... Supercapacitive performance of hydrous ruthenium oxide (RuO2. .... transport studies of RAgSn2 compounds (R = Y, Tb, Dy, Ho and Er) with Cu3Au-type .... Structural characterization and complex impedance studies on fast ion conducting ...

Static magnetic susceptibility, crystal field and exchange interactions in rare earth titanate pyrochlores

NARCIS (Netherlands)

Malkin, B. Z.; Lummen, T. T. A.; van Loosdrecht, P. H. M.; Dhalenne, G.; Zakirov, A. R.

2010-01-01

The experimental temperature dependence (T = 2-300 K) of single crystal bulk and site susceptibilities of rare earth titanate pyrochlores R2Ti2O7 (R = Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb) is analyzed in the framework of crystal field theory and a mean field approximation. Analytical expressions for the

Magnetocrystalline anisotropy in a (110) (Tb0.27Dy0.73)Fe2 thin-film

International Nuclear Information System (INIS)

Fuente, C de la; Arnaudas, J I; Benito, L; Ciria, M; Moral, A del; Dufour, C; Dumesnil, K

2004-01-01

Magnetic anisotropy measurements performed in a (110) (Tb 0.27 Dy 0.73 )Fe 2 (Terfenol-D) film epitaxially grown on a sapphire substrate are presented. The magnetic torque curves have been determined by using a vectorial vibrating sample magnetometer, which allows us to measure the angular dependence of magnetization components parallel, M parallel , and perpendicular, M perp , to the applied field up to 2 T. The fourfold symmetry associated with the cubic structure within the (110) plane is clearly observed. The analysis of the experimental torque has been carried out considering magnetocrystalline anisotropy up to sixth order and magnetoelastic energy up to second order; so, the magnetocrystalline anisotropy constants in the (110) plane of the film, K 1 and K 2 , have been obtained. This allows us to determine the direction of the magnetization easy axis for (110) Terfenol-D thin-film: it is [1bar12] at RT, passes through [3bar34] at 140 K and then changes to [1bar20] at 40 K. It was completely impossible to explain the angular dependence of the experimental magnetic torque without including shear and tetragonal magnetoelastic stress parameters, b 2 and b 1 , respectively. This confirms the paramount role of the strain in the determination of the magnetic properties in this kind of Terfenol-D thin film

Local rhombohedral symmetry in Tb{sub 0.3}Dy{sub 0.7}Fe{sub 2} near the morphotropic phase boundary

Energy Technology Data Exchange (ETDEWEB)

Ma, Tianyu, E-mail: maty@zju.edu.cn [State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Key Laboratory of Novel Materials for Information Technology of Zhejiang Province, Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027 (China); Ferroic Physics Group, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047, Ibaraki (Japan); Liu, Xiaolian; Pan, Xingwen; Li, Xiang; Jiang, Yinzhu; Yan, Mi, E-mail: mse-yanmi@zju.edu.cn [State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Key Laboratory of Novel Materials for Information Technology of Zhejiang Province, Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027 (China); Li, Huiying; Fang, Minxia [Multi-disciplinary Materials Research Center, Frontier Institute of Science and Technology, Xi' an Jiaotong University, Xi' an 710049 (China); Ren, Xiaobing, E-mail: ren.xiaobing@nims.go.jp [Ferroic Physics Group, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047, Ibaraki (Japan); Multi-disciplinary Materials Research Center, Frontier Institute of Science and Technology, Xi' an Jiaotong University, Xi' an 710049 (China)

2014-11-10

The recently reported morphotropic phase boundary (MPB) in a number of giant magnetostrictive materials (GMMs) has drawn considerable interest to the local symmetry/structure near MPB region of these materials. In this letter, by in-situ X-ray diffraction and AC magnetic susceptibility measurements, we show that Tb{sub 0.3}Dy{sub 0.7}Fe{sub 2}, the typical composition of Terfenol-D GMMs, has coexistence of rhombohedral and tetragonal phases over a wide temperature range in the vicinity of MPB. High resolution transmission electron microscopy provides direct evidence for local rhombohedral symmetry of the ferromagnetic phase and reveals regular-shaped nanoscale domains below 10 nm. The nano-sized structural/magnetic domains are hierarchically inside a single micron-sized stripe-like domain with the same average magnetization direction. Such domain structures are consistent with the low magnetocrystalline anisotropy and easy magnetic/structural domain switching under magnetic field, thus generating large magnetostriction at low field.

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)

β-γ and isomeric decay spectroscopy of 168Dy

Directory of Open Access Journals (Sweden)

Zhang G.X.

2018-01-01

Full Text Available This contribution will report on the experimental work on the level structure of 168Dy. The experimental data have been taken as part of the EURICA decay spectroscopy campaign at RIBF, RIKEN in November 2014. In the experiment, a 238U primary beam is accelerated up to 345 MeV/u with an average intensity of 12 pnA. The nuclei of interest are produced by in-flight fission of 238U impinging on Be target with a thickness of 5 mm. The excited states of 168Dy have been populated through the decay from a newly identified isomeric state and via the β decay from 168Tb. In this contribution, scientific motivations, experimental procedure and some preliminary results for this study are presented.

β-γ and isomeric decay spectroscopy of 168Dy

Science.gov (United States)

Zhang, G. X.; Watanabe, H.; Kondev, F. G.; Lane, G. J.; Regan, P. H.; Söderström, P.-A.; Walker, P. M.; Kanaoka, H.; Korkulu, Z.; Lee, P. S.; Liu, J. J.; Nishimura, S.; Wu, J.; Yagi, A.; Ahn, D. S.; Alharbi, T.; Baba, H.; Browne, F.; Bruce, A. M.; Carroll, R. J.; Chae, K. Y.; Dombradi, Zs.; Doornenbal, P.; Estrade, A.; Fukuda, N.; Griffin, C.; Ideguchi, E.; Inabe, N.; Isobe, T.; Kanaya, S.; Kojouharov, I.; Kubo, T.; Kubono, S.; Kurz, N.; Kuti, I.; Lalkovski, S.; Lee, C. S.; Lee, E. J.; Lorusso, G.; Lotay, G.; Moon, C.-B.; Nishizuka, I.; Nita, C. R.; Odahara, A.; Patel, Z.; Phong, V. H.; Podolyák, Zs.; Roberts, O. J.; Sakurai, H.; Schaffner, H.; Shand, C. M.; Shimizu, Y.; Sumikama, T.; Suzuki, H.; Takeda, H.; Terashima, S.; Vajta, Zs.; Valiente-Dóbon, J. J.; Xu, Z. Y.

2018-05-01

This contribution will report on the experimental work on the level structure of 168Dy. The experimental data have been taken as part of the EURICA decay spectroscopy campaign at RIBF, RIKEN in November 2014. In the experiment, a 238U primary beam is accelerated up to 345 MeV/u with an average intensity of 12 pnA. The nuclei of interest are produced by in-flight fission of 238U impinging on Be target with a thickness of 5 mm. The excited states of 168Dy have been populated through the decay from a newly identified isomeric state and via the β decay from 168Tb. In this contribution, scientific motivations, experimental procedure and some preliminary results for this study are presented.

Synthesis and luminescence properties of BaTiO3:RE (RE = Gd , Dy ...

Indian Academy of Sciences (India)

thermoluminescence (TL) properties of BaTiO3 samples doped with Gd3+, Dy3+, Tb3+ and Lu3+ were investigated. ... electron microscope using an accelerating voltage of 20 kV. .... doping of 1% mole Gd3+ ion into the BaTiO3 compound.

Exchange coupling and magnetic anisotropy in a family of bipyrimidyl radical-bridged dilanthanide complexes: density functional theory and ab initio calculations.

Science.gov (United States)

Zhang, Yi-Quan; Luo, Cheng-Lin; Zhang, Qiang

2014-05-05

The origin of the magnetic anisotropy energy barriers in a series of bpym(-) (bpym = 2,2'-bipyrimidine) radical-bridged dilanthanide complexes [(Cp*2Ln)2(μ-bpym)](+) [Cp* = pentamethylcyclopentadienyl; Ln = Gd(III) (1), Tb(III) (2), Dy(III) (3), Ho(III) (4), Er(III) (5)] has been explored using density functional theory (DFT) and ab initio methods. DFT calculations show that the exchange coupling between the two lanthanide ions for each complex is very weak, but the antiferromagnetic Ln-bpym(-) couplings are strong. Ab initio calculations show that the effective energy barrier of 2 or 3 mainly comes from the contribution of a single Tb(III) or Dy(III) fragment, which is only about one third of a single Ln energy barrier. For 4 or 5, however, both of the two Ho(III) or Er(III) fragments contribute to the total energy barrier. Thus, it is insufficient to only increase the magnetic anisotropy energy barrier of a single Ln ion, while enhancing the Ln-bpym(-) couplings is also very important. Copyright © 2014 Wiley Periodicals, Inc.

First principle studies of electronic and magnetic properties of Lanthanide-Gold (RAu) binary intermetallics

Energy Technology Data Exchange (ETDEWEB)

Ahmad, Sardar [Center for Computational Materials Science, University of Malakand, Chakdara, 18800 Pakistan (Pakistan); Department of Chemistry, University of Malakand, Chakdara, 18800 Pakistan (Pakistan); Ahmad, Rashid, E-mail: rashmad@gmail.com [Center for Computational Materials Science, University of Malakand, Chakdara, 18800 Pakistan (Pakistan); Department of Chemistry, University of Malakand, Chakdara, 18800 Pakistan (Pakistan); Jalali-Asadabadi, S. [Department of Physics, Faculty of Sciences, University of Isfahan (UI), Hezar Gerib Avenue, Isfahan 81746-73441 (Iran, Islamic Republic of); Ali, Zahid [Center for Computational Materials Science, University of Malakand, Chakdara, 18800 Pakistan (Pakistan); Department of Physics, University of Malakand, Chakdara, 18800 Pakistan (Pakistan); Ahmad, Iftikhar [Center for Computational Materials Science, University of Malakand, Chakdara, 18800 Pakistan (Pakistan); Vice Chancellor, Abbott Abad University of Science and Technology, Abbott Abad (Pakistan)

2017-01-15

In this article we explore the electronic and magnetic properties of RAu intermetallics (R=Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) for the first time. These properties are calculated by using GGA, GGA+U and hybrid density functional theory (HF) approaches. Our calculations show that HF provides superior results, consistent to the experimentally reported data. The chemical bonding between rare-earth and gold atoms within these compounds are explained on the basis of spin dependent electronic clouds in different planes, which shows predominantly ionic and metallic nature between Au and R atoms. The Cohesive energies of RAu compounds show direct relation with the melting points. Spin-dependent electronic band structure demonstrates that all these compounds are metallic in nature. The magnetic studies show that HoAu and LuAu are stable in non-magnetic structure, PrAu is stable in ferromagnetic phase and CeAu, NdAu, SmAu, GdAu, TbAu, DyAu, ErAu, TmAu, YbAu are anti-ferromagnetic materials.

Structural imitation and lattice vibration of R{sub 2}Co{sub 17-x}Mn{sub x} (R=Dy, Ho)

Energy Technology Data Exchange (ETDEWEB)

Qian Ping [Institute of Applied Physics, University of Science and Technology Beijing, Beijing 100083 (China)]. E-mail: qianpinghu@sohu.com; Chen Nanxian [Institute of Applied Physics, University of Science and Technology Beijing, Beijing 100083 (China); Department of Physics, Tsinghua University, Beijing 100084 (China); Shen Jiang [Institute of Applied Physics, University of Science and Technology Beijing, Beijing 100083 (China)

2005-02-21

The intermetallics R{sub 2}Co{sub 17-x}Mn{sub x} (R=Dy, Ho) have been studied to ascertain the effect of partial replacement of Co by Mn on their phase stability and site preference. Calculation is based on a series of interatomic pair potentials related to the rare earth and transition metals, which are obtained by a strict lattice inversion method. Our results indicate that the Mn atom can stabilize R{sub 2}Co{sub 17-x}Mn{sub x} with Th{sub 2}Zn{sub 17}-type structure. And Mn atom preferentially substitutes for Co in the 6c site and randomly substitutes in the 18f and 18h site. The differences of lattice constants between the calculated and the experimental values are about or even smaller than 2%. The properties related to lattice vibration, such as phonon density of states and Debye temperature, are also evaluated for these materials. The method utilized in the present investigation offers a rather easy and direct way to study the structural and vibrational properties of R{sub 2}Co{sub 17-x}Mn{sub x}.

Production of a tracer packet of heavier rare earth elements

International Nuclear Information System (INIS)

Lahiri, S.; Nayak, D.; Maji, S.

2004-01-01

Production of a tracer packet of heavier rare earth elements containing carrier-free radionuclides of 153,155 Tb, 153,155,157 Dy, 159 Ho, 159,161 Er, 161 Tm produced by medium energy 7 Li and 12 C irradiation on an europium oxide target and the subsequent separation of bulk europium from the carrier-free products is described. (author)

Synthesis of Halide- and Solvent free metal borohydrides

DEFF Research Database (Denmark)

Grinderslev, Jakob; Møller, Kasper Trans; Jensen, Torben René

chloride or LiBH4 is present in the sample. The synthesis pathway has been shown to work for most of the already known metal borohydrides, M = Na, Ca, Sr, Ba, Y, La, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb, but also new borohydrides are formed, M = Pr, Nd and Lu. Besides new compounds, new polymorphs...

Transferred hyperfine interaction at 295 K between the rare-earth ions and the fluorine and lithium nuclei in lithium rare-earth fluorides

DEFF Research Database (Denmark)

Hansen, P. E.; Nevald, Rolf

1977-01-01

The nuclear-magnetic-resonance rotation spectra for the fluorine and lithium nuclei in LiTbF4, LiDyF4, LiHoF4, and LiErF4 have been obtained at 295 K. They are separated in contributions from the dipole and the transferred hyperfine interactions. In general, the latter consists of an isotropic part...

Fusion of 6Li with 159Tb at near-barrier energies

International Nuclear Information System (INIS)

Pradhan, M. K.; Mukherjee, A.; Basu, P.; Goswami, A.; Kshetri, R.; Roy, Subinit; Chowdhury, P. Roy; Sarkar, M. Saha; Palit, R.; Parkar, V. V.; Santra, S.; Ray, M.

2011-01-01

Complete and incomplete fusion cross sections for 6 Li + 159 Tb have been measured at energies around the Coulomb barrier by the γ-ray method. The measurements show that the complete fusion cross sections at above-barrier energies are suppressed by ∼34% compared to coupled-channel calculations. A comparison of the complete fusion cross sections at above-barrier energies with the existing data for 11,10 B + 159 Tb and 7 Li + 159 Tb shows that the extent of suppression is correlated with the α separation energies of the projectiles. It has been argued that the Dy isotopes produced in the reaction 6 Li + 159 Tb at below-barrier energies are primarily due to the d transfer to unbound states of 159 Tb, while both transfer and incomplete fusion processes contribute at above-barrier energies.

em cristais de Ho:YLF e Er:YLF na região de 3m

Directory of Open Access Journals (Sweden)

Fábio Henrique Jagosich

2006-01-01

Full Text Available In this work, the deactivation energy transfer mechanisms of 4I13/2 of Er3+ and 5I7 of Ho3+ levels in crystals of LiYF4 (YLF co-doped with Nd3+, Tb3+ and Eu3+ are studied. It was determined the best combination with deactivator ions, capable to maximize the laser gain in the middle of the Ho3+ in 2.9 micrometers (mm and the Er3+ in 2.75 mm operation. The results showed that the Tb3+ and Eu3+ are the best deactivators to the Ho3+ laser operation, while for the Ho3+ laser operation, the best ion deactivator is the Nd3+. The energy transfer characterizations were carried out using the Förster-Dexter method, which consists in the determination of the interaction critic ray, to start from the integral superposition of the absorption cross section spectrum and the involved ions emission.

Structural elucidation and magnetic behavior evaluation of rare earth (La, Nd, Gd, Tb, Dy) doped BaCoNi-X hexagonal nano-sized ferrites

International Nuclear Information System (INIS)

Majeed, Abdul; Khan, Muhammad Azhar; Raheem, Faseeh ur; Hussain, Altaf; Iqbal, F.; Murtaza, Ghulam; Akhtar, Majid Niaz; Shakir, Imran; Warsi, Muhammad Farooq

2016-01-01

Rare-earth (RE=La 3+ , Nd 3+ , Gd 3+ , Tb 3+ , Dy 3+ ) doped Ba 2 NiCoRE x Fe 28−x O 46 (x=0.25) hexagonal ferrites were synthesized for the first time via micro-emulsion route, which is a fast chemistry route for obtaining nano-sized ferrite powders. These nanomaterials were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), as well as vibrating sample magnetometer (VSM). The XRD analysis exhibited that all the samples crystallized into single X-type hexagonal phase. The crystalline size calculated by Scherrer's formula was found in the range 7–19 nm. The variations in lattice parameters elucidated the incorporation of rare-earth cations in these nanomaterials. FTIR absorption spectra of these X-type ferrites were investigated in the wave number range 500–2400 cm −1. Each spectrum exhibited absorption bands in the low wave number range, thereby confirming the X-type hexagonal structure. The enhancement in the coercivity was observed with the doping of rare-earth cations. The saturation magnetization was lowered owing to the redistribution of rare-earth cations on the octahedral site (3b VI ). The higher values of coercivity (664–926 Oe) of these nanomaterials suggest their use in longitudinal recording media. - Graphical abstract: Nano-sized rare-earth (RE=La 3+ , Nd 3+ , Gd 3+ , Tb 3+ , Dy 3+ ) doped Ba 2 NiCoRE x Fe 28−x O 46 (x=0.25) hexagonal ferrites were synthesized for the first time via micro-emulsion route and the crystallite size was found in the range 7–19 nm. The enhancement in the coercivity was observed with the doping of rare-earth cations. The higher values of coercivity (664–926 Oe) of these nanomaterials suggest their use in longitudinal recording media. - Highlights: • Micro-emulsion route was used to synthesize Ba 2 NiCoRE x Fe 28−x O 46 ferrites. • The crystallite size was found in the range 7–19 nm. • The rare-earth incorporation enhanced the coercivity (664–926 Oe). �

Preparation and characterization of the adducts between lanthanide methanesulfonates and thioxane oxide

International Nuclear Information System (INIS)

Castro e Silva, E. de.

1983-01-01

The preparation and characterization of the adduct between lanthanide methanesulphonates and thioxane oxide are presented. The compounds characterization by conductance measurements, X-ray powder patterns, infrared, visible and fluorescence spectra, TG, DTG and DTA curves was made. According to the X-ray patterns, three isomorphous series were obtained: a-La-Gd b-Tb-Dy and c-Ho-Lu, Y. (M.J.C.) [pt

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

The rare earth elements like La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and the heavy metals like Mg, V, Cr, Mn, Fe, Cu, Zn, U, Th were analysed by using standard analytical methods. The Post-Archean Australian Shale composition was used to normalise the rare earth elements. It was found that the sediments ...

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Abstract. Elastic moduli (, ), Poisson's ratio (), microhardness () and some thermodynamical parameters such as Debye temperature (), diffusion constant (), latent heat of melting ( ) etc of PbO–Al2O3–B2O3 glasses doped with rare earth ions viz. Pr3+, Nd3+, Sm3+, Eu3+, Tb3+, Dy3+, Ho3+, Er3+ and Yb3+, ...

Magnetic properties of RNi5-xCux intermetallics

International Nuclear Information System (INIS)

Kuchin, A.G.; Ermolenko, A.S.; Kulikov, Yu.A.; Khrabrov, V.I.; Rosenfeld, E.V.; Makarova, G.M.; Lapina, T.P.; Belozerov, Ye.V.

2006-01-01

The magnetic properties have been studied for the series of RNi 5-x Cu x intermetallics with R=Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Lu; x= 5-x Cu x but GdNi 5-x Cu x . These results are explained in the frame of band magnetism, random local crystal field, and domain wall pinning theories

Oxygen stabilized rare-earth iron intermetallic compounds

International Nuclear Information System (INIS)

Dariel, M.P.; Malekzadeh, M.; Pickus, M.R.

1975-10-01

A new, oxygen-stabilized intermetallic compound was identified in sintered, pre-alloyed rare-earth iron powder samples. Its composition corresponds to formula R 12 Fe 32 O 2 and its crystal structure belongs to space group Im3m. The presence of these compounds was observed, so far, in several R--Fe--O systems, with R = Gd, Tb, Dy, Ho, Er, and Y

Synthesis, structure, luminescent, and magnetic properties of carbonato-bridged Zn(II)2Ln(III)2 complexes [(μ4-CO3)2{Zn(II)L(n)Ln(III)(NO3)}2] (Ln(III) = Gd(III), Tb(III), Dy(III); L(1) = N,N'-bis(3-methoxy-2-oxybenzylidene)-1,3-propanediaminato, L(2) = N,N'-bis(3-ethoxy-2-oxybenzylidene)-1,3-propanediaminato).

Science.gov (United States)

Ehama, Kiyomi; Ohmichi, Yusuke; Sakamoto, Soichiro; Fujinami, Takeshi; Matsumoto, Naohide; Mochida, Naotaka; Ishida, Takayuki; Sunatsuki, Yukinari; Tsuchimoto, Masanobu; Re, Nazzareno

2013-11-04

Carbonato-bridged Zn(II)2Ln(III)2 complexes [(μ4-CO3)2{Zn(II)L(n)Ln(III)(NO3)}2]·solvent were synthesized through atmospheric CO2 fixation reaction of [Zn(II)L(n)(H2O)2]·xH2O, Ln(III)(NO3)3·6H2O, and triethylamine, where Ln(III) = Gd(III), Tb(III), Dy(III); L(1) = N,N'-bis(3-methoxy-2-oxybenzylidene)-1,3-propanediaminato, L(2) = N,N'-bis(3-ethoxy-2-oxybenzylidene)-1,3-propanediaminato. Each Zn(II)2Ln(III)2 structure possessing an inversion center can be described as two di-μ-phenoxo-bridged {Zn(II)L(n)Ln(III)(NO3)} binuclear units bridged by two carbonato CO3(2-) ions. The Zn(II) ion has square pyramidal coordination geometry with N2O2 donor atoms of L(n) and one oxygen atom of a bridging carbonato ion at the axial site. Ln(III) ion is coordinated by nine oxygen atoms consisting of four from the deprotonated Schiff-base L(n), two from a chelating nitrate, and three from two carbonate groups. The temperature-dependent magnetic susceptibilities in the range 1.9-300 K, field-dependent magnetization from 0 to 5 T at 1.9 K, and alternating current magnetic susceptibilities under the direct current bias fields of 0 and 1000 Oe were measured. The magnetic properties of the Zn(II)2Ln(III)2 complexes are analyzed on the basis of the dicarbonato-bridged binuclear Ln(III)-Ln(III) structure, as the Zn(II) ion with d(10) electronic configuration is diamagnetic. ZnGd1 (L(1)) and ZnGd2 (L(2)) show a ferromagnetic Gd(III)-Gd(III) interaction with J(Gd-Gd) = +0.042 and +0.028 cm(-1), respectively, on the basis of the Hamiltonian H = -2J(Gd-Gd)ŜGd1·ŜGd2. The magnetic data of the Zn(II)2Ln(III)2 complexes (Ln(III) = Tb(III), Dy(III)) were analyzed by a spin Hamiltonian including the crystal field effect on the Ln(III) ions and the Ln(III)-Ln(III) magnetic interaction. The Stark splitting of the ground state was so evaluated, and the energy pattern indicates a strong easy axis (Ising type) anisotropy. Luminescence spectra of Zn(II)2Tb(III)2 complexes were observed, while those

Features of magnetic and thermal properties of R(Co{sub 1−x}Fe{sub x}){sub 2} (x≤0.16) quasibinary compounds with R=Dy, Ho, Er

Energy Technology Data Exchange (ETDEWEB)

Anikin, Maksim; Tarasov, Evgeniy; Kudrevatykh, Nikolay [Institute of Natural Sciences, Ural Federal University, Ekaterinburg 620002 (Russian Federation); Inishev, Aleksander [Institute of Metal Physics, Ekaterinburg 620137 (Russian Federation); Semkin, Mikhail; Volegov, Aleksey; Zinin, Aleksander [Institute of Natural Sciences, Ural Federal University, Ekaterinburg 620002 (Russian Federation)

2016-11-15

In this work the results of measurements of high field susceptibility, paraprocess susceptibility and thermal properties of R(Co{sub 1−x}Fe{sub x}){sub 2} intermetallic compounds (R=Dy, Ho, Er and x=(0−0.16)) are presented (heat capacity and magnetocaloric effect (MCE)). A magnetic structure of the Ho(Co{sub 0.88}Fe{sub 0.12}){sub 2} at 293 K and 78 K was studied by neutron powder diffraction. Some peculiarities of a high-field susceptibility were revealed at low temperatures and around the Curie point (T{sub C}). In temperature range lower than T{sub C} by (100–150) K, magnetic contributions to a zero-field heat capacity were found. Studying MCE in wide temperatures range, the large change of the entropy magnetic contribution (∆S) was observed which correlates with ∆T phenomenon. In particular, for the Er(Co{sub 0.84}Fe{sub 0.16}){sub 2} compound the ∆S value at low temperatures is six times higher than that at Curie point. The possible reasons of such behavior were discussed. - Highlights: • Magnetic and magnetocaloric properties of R(Co–Fe){sub 2} compounds have been studied. • Fe introduction induces the disorientation effect in Ho-ions magnetic ordering. • Emergence of magnetic contribution to a heat capacity at temperatures less T{sub C}. • The existence of a broad maximum on a temperature dependence of the MCE. • Direct MCE measurements at magnetic field of (0–17.5) kOe have been performed.

Neutron scattering study on R2PdSi3 (R=Ho,Er,Tm) compounds

International Nuclear Information System (INIS)

Tang, Fei

2010-01-01

Previous studies on the family of inter-metallic rare-earth compounds R 2 PdSi 3 revealed multifaceted magnetic properties, for instance, spin-glass like behavior. Experimental observations include: Signs of a crystallographic superstructure, complicated magnetic structures both in zero field and in applied magnetic fields as well as a generic phase in applied fields for compounds in the series with the heavy rare-earths R=Gd, Tb, Dy, Ho, Er and Tm. This thesis expands the studies on the magnetic properties of R 2 PdSi 3 employing mainly neutron scattering on single crystals with the focus on the compounds with R=Ho, Er and Tm. A detailed analysis of the crystallographic superstructure using modulation wave approach and group theory is presented. The resulting structure implies the existence of two different rare-earth sites with reduced symmetry and an arrangement of the different sites according to sequences as determined by the superstructure. It is shown that the reduced symmetry of the rare-earth sites is explicitly observed in the energy spectra of inelastic neutron scattering. The results on the magnetic structures and excitations are shown and discussed in the framework of the superstructure model. Specifically the generic phase in applied fields is interpreted as a direct consequence of the crystallographic superstructure. It is rather unusual that a crystallographic superstructure is playing such a decisive, and through the field dependence also tunable role in determining the magnetic properties as observed in R 2 PdSi 3 . The mediating interactions between the crystallographic part and the magnetic part of the system are discussed. (orig.)

Luminescence and magnetic behaviour of almond like (Na{sub 0.5}La{sub 0.5})MoO{sub 4}:RE{sup 3+} (RE = Eu, Tb, Dy) nanostructures

Energy Technology Data Exchange (ETDEWEB)

Krishnan, Rajagopalan [Department of Physics, B.S. Abdur Rahman University, Vandalur, Chennai, Tamil Nadu (India); Thirumalai, Jagannathan, E-mail: jthirumalai@bsauniv.ac.in [Department of Physics, B.S. Abdur Rahman University, Vandalur, Chennai, Tamil Nadu (India); Thomas, Sabu [Polymer Science and Technology, Center for Nanoscience and Nanotechnology, School of Chemical Sciences, Mahatma Gandhi University, Kottayam 686 560, Kerala (India); Gowri, Mahasampath [Department of Chemistry, B.S. Abdur Rahman University, Vandalur, Chennai, Tamil Nadu (India)

2014-08-01

Graphical abstract: Monodispersed almond-like (Na{sub 0.5}La{sub 0.5})MoO{sub 4}:RE{sup 3+} nanostructures synthesized by employing ethylene-diamine tetra acetic acid (EDTA) using hydrothermal route at 200 °C for 24 h. These nanoparticles were found to be novel bi-functional candidates suitable for high-quality luminescence and magnetic applications. - Highlights: • Almond like structures of (Na{sub 0.5}La{sub 0.5})MoO{sub 4}:RE{sup 3+} were synthesized by hydrothermal method. • Time dependent self-assembly could be the dominant process for the formation of 3D networks. • Luminescence properties of nanosamples were studied in comparison with bulk sample. • Room temperature magnetic properties of bulk and nanophosphors were investigated. - Abstract: Tetragonal phase (Na{sub 0.5}La{sub 0.5})MoO{sub 4}:RE{sup 3+} (RE = Eu, Tb, Dy) with almond like hierarchical structures assembled from nanosheets building blocks were successfully synthesized by employing disodium ethylenediaminetetraacetic acid (Na{sub 2}EDTA) using hydrothermal route at 200 °C for 24 h. Field emission scanning electron microscope, transmission electron microscope, and X-ray diffraction patterns were used to characterize the morphology, size, and crystal structure with good resolution. The sequestering agent EDTA acts as quadridentate ligand coordinated with metal ions [Na{sup +}, La{sup 3+}/RE{sup 3+}] facilitating the formation of self-organized 3D networks. The growth mechanism for the formation of almond like nanostructures is explicated in four paths: dissolution, adsorption, in situ transformation in acidic and basic media and the effective collision. Photoluminescence excitation and emission spectra reveals a spectral blue shift which was observed in the nanosamples towards shorter wavelengths compared with the bulk sample. Upon UV irradiation, both bulk and nanostructure show strong luminescence in the red region due to the {sup 5}D{sub 0} → {sup 7}F{sub 2} transition in Eu{sup 3

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

Rhodium-rich silicides RERh{sub 6}Si{sub 4} (RE=La, Nd, Tb, Dy, Er, Yb)

Energy Technology Data Exchange (ETDEWEB)

Vosswinkel, Daniel; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie

2017-07-01

Polycrystalline RERh{sub 6}Si{sub 4} (RE=La, Nd, Tb, Dy, Er, Yb) samples can be synthesized by arc-melting of the elements. Single crystals of LaRh{sub 6}Si{sub 4}, NdRh{sub 6}Si{sub 4} and YbRh{sub 6}Si{sub 4} were synthesized from the elements in bismuth fluxes (non-reactive flux medium). The structures were refined on the basis of single-crystal X-ray diffractometer data: LiCo{sub 6}P{sub 4} type, P anti 6m2, a=700.56(3), c=380.55(1) pm, wR2=0.0257, 317 F{sup 2} values, 19 variables for LaRh{sub 6}Si{sub 4}, a=698.4(5), c=377.7(2) pm, wR2=0.0578, 219 F{sup 2} values, 19 variables for NdRh{sub 6}Si{sub 4} and a=696.00(3), c=371.97(1) pm, wR2=0.0440, 309 F{sup 2} values, 19 variables for YbRh{sub 6}Si{sub 4}. The rhodium and silicon atoms build up three-dimensional, covalently bonded [Rh{sub 6}Si{sub 4}]{sup δ-} polyanionic networks with Rh-Si distances ranging from 239 to 249 pm. The rare earth atoms fill larger cavities within channels of these networks and they are coordinated by six silicon and twelve rhodium atoms in the form of hexa-capped hexagonal prisms.

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)

Posouzení stability kotevního systému

OpenAIRE

Krško, Matúš

2012-01-01

Bakalárska práca je zameraná na problematiku stability kotevného systému. Teoretická časť sa zaoberá rozdelením a technológiou výstavby kotvených stien a poruchovými stavmi, ktoré môžu nastať. Ďalej sú predstavené metódy na posúdenie vnútornej stability systému. Vo výpočtovej časti sú tieto metódy aplikované na vzorový príklad. V závere práce sú získané výsledky vyhodnotené. Bachelor´s thesis is focused on stability of anchored system. Theoretical part deals with various types of anchored ...

Syntheses of rare-earth metal oxide nanotubes by the sol-gel method assisted with porous anodic aluminum oxide templates

International Nuclear Information System (INIS)

Kuang Qin; Lin Zhiwei; Lian Wei; Jiang Zhiyuan; Xie Zhaoxiong; Huang Rongbin; Zheng Lansun

2007-01-01

In this paper, we report a versatile synthetic method of ordered rare-earth metal (RE) oxide nanotubes. RE (RE=Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb) oxide nanotubes were successfully prepared from corresponding RE nitrate solution via the sol-gel method assisted with porous anodic aluminum oxide (AAO) templates. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM, and X-ray diffraction (XRD) have been employed to characterize the morphology and composition of the as-prepared nanotubes. It is found that as-prepared RE oxides evolve into bamboo-like nanotubes and entirely hollow nanotubes. A new possible formation mechanism of RE oxide nanotubes in the AAO channels is proposed. These high-quantity RE oxide nanotubes are expected to have promising applications in many areas such as luminescent materials, catalysts, magnets, etc. - Graphical abstract: A versatile synthetic method for the preparation of ordered rare-earth (RE) oxide nanotubes is reported, by which RE (RE=Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb) oxide nanotubes were successfully prepared from corresponding RE nitrate solution via the sol-gel method assisted with porous anodic aluminum oxide (AAO) templates

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)

Investigation of the generation of several long-lived radionuclides of importance in fusion reactor technology: Report on a Coordinated Research Program sponsored by the International Atomic Energy Agency

International Nuclear Information System (INIS)

Smith, D.L.; Pashchenko, A.B.

1994-01-01

The IAEA initiated a Coordinated Research Program (CRP) in 1988 to obtain reliable information for 16 long-lived activation reactions of special importance to fusion reactor technology: 27 Al (n, 2n) 26 Al, 63 Cu(n,p) 63 Ni, 94 Mo(n,p) 94 Nb, 109 Ag(n,2n) 108m Ag, 179 Hf(n,2n) 178m2 Hf, 182 W(n,n ' a) 178m2 Hf, 151 Eu(n,2n) 150 gEu, 153 Eu(n,2n) 152+m2 Eu, 159 Tb(n, 2n) 158 Tb, 158 Dy(n,p) 158 Tb, 193 Ir(n,2n) 192m2 Ir, 187 Re(n,2n) 186m Re, 62 Ni(nγ) 63 Ni, 98 Mo(n,γ) 99 Mo(β-) 99 Tc, 165 Ho(n,γ) 166m Ho and 191 Ir(n,γ) 192m2 Ir. this paper documents progress achieved from the start of the program through mid- 1993

Separation and Recycling for Rare Earth Elements by Homogeneous Liquid-Liquid Extraction (HoLLE Using a pH-Responsive Fluorine-Based Surfactant

Directory of Open Access Journals (Sweden)

Shotaro Saito

2015-08-01

Full Text Available A selective separation and recycling system for metal ions was developed by homogeneous liquid-liquid extraction (HoLLE using a fluorosurfactant. Sixty-two different elemental ions (e.g., Ag, Al, As, Au, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Hg, Ho, In, Ir, La, Lu, Mg, Mn, Mo, Nb, Nd, Ni, Os, P, Pb, Pd, Pr, Pt, Re, Rh, Ru, Sb, Sc, Se, Si, Sm, Sn, Sr, Ta, Tb, Te, Ti, Tl, Tm, V, W, Y, Yb, Zn, and Zr were examined. By changing pH from a neutral or alkaline solution (pH ≥ 6.5 to that of an acidic solution (pH < 4.0, gallium, zirconium, palladium, silver, platinum, and rare earth elements were extracted at >90% efficiency into a sedimented Zonyl FSA® (CF3(CF2n(CH22S(CH22COOH, n = 6–8 liquid phase. Moreover, all rare earth elements were obtained with superior extraction and stripping percentages. In the recycling of rare earth elements, the sedimented phase was maintained using a filter along with a mixed solution of THF and 1 M sodium hydroxide aqueous solution. The Zonyl FSA® was filtrated and the rare earth elements were recovered on the filter as a hydroxide. Furthermore, the filtrated Zonyl FSA was reusable by conditioning the subject pH.

Powder Neutron Diffraction and Magnetic structures

International Nuclear Information System (INIS)

Vigneron, F.

1986-01-01

The determination of the magnetic structures of materials (ferromagnetic, antiferromagnetic, helimagnetic, .) can be achieved only by neutron diffraction. A general survey of the powder technique is given: 2-axis spectrometer and analysis of the magnetic data. For the REBe/sb13/ intermetallic compounds (RE = Rare Earth), commensurate and/or incommensurate magnetic structures are observed and discussed as a function of RE (Gd, Tb, Dy, Ho, Er)

Miljøundersøgelser ved Kvanefjeldet 2001

DEFF Research Database (Denmark)

Asmund, G.

jordarter' (La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu) Af de mange grundstoffer, der er undersøgt er det kun 'Sjældne jordarter', zirkonium, niobium og thorium, der viser forhøjelser i forhold til baggrundsværdier og samtidigt er stærkt forhøjede i det vand, der siver ud fra minen. Imidlertid fandtes denne...

Structural elucidation and magnetic behavior evaluation of rare earth (La, Nd, Gd, Tb, Dy) doped BaCoNi-X hexagonal nano-sized ferrites

Energy Technology Data Exchange (ETDEWEB)

Majeed, Abdul, E-mail: abdulmajeed2276@gmail.com [Department of Physics, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Khan, Muhammad Azhar, E-mail: azhar.khan@iub.edu.pk [Department of Physics, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Raheem, Faseeh ur; Hussain, Altaf; Iqbal, F. [Department of Physics, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Murtaza, Ghulam [Centre for Advanced Studies in Physics, Government College University, Lahore 54000 (Pakistan); Akhtar, Majid Niaz [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Shakir, Imran [Deanship of Scientific Research, College of Engineering, King Saud University, PO Box 800, Riyadh 11421 (Saudi Arabia); Warsi, Muhammad Farooq [Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan)

2016-06-15

Rare-earth (RE=La{sup 3+}, Nd{sup 3+}, Gd{sup 3+}, Tb{sup 3+}, Dy{sup 3+}) doped Ba{sub 2}NiCoRE{sub x}Fe{sub 28−x}O{sub 46} (x=0.25) hexagonal ferrites were synthesized for the first time via micro-emulsion route, which is a fast chemistry route for obtaining nano-sized ferrite powders. These nanomaterials were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), as well as vibrating sample magnetometer (VSM). The XRD analysis exhibited that all the samples crystallized into single X-type hexagonal phase. The crystalline size calculated by Scherrer's formula was found in the range 7–19 nm. The variations in lattice parameters elucidated the incorporation of rare-earth cations in these nanomaterials. FTIR absorption spectra of these X-type ferrites were investigated in the wave number range 500–2400 cm{sup −1.} Each spectrum exhibited absorption bands in the low wave number range, thereby confirming the X-type hexagonal structure. The enhancement in the coercivity was observed with the doping of rare-earth cations. The saturation magnetization was lowered owing to the redistribution of rare-earth cations on the octahedral site (3b{sub VI}). The higher values of coercivity (664–926 Oe) of these nanomaterials suggest their use in longitudinal recording media. - Graphical abstract: Nano-sized rare-earth (RE=La{sup 3+}, Nd{sup 3+}, Gd{sup 3+}, Tb{sup 3+}, Dy{sup 3+}) doped Ba{sub 2}NiCoRE{sub x}Fe{sub 28−x}O{sub 46} (x=0.25) hexagonal ferrites were synthesized for the first time via micro-emulsion route and the crystallite size was found in the range 7–19 nm. The enhancement in the coercivity was observed with the doping of rare-earth cations. The higher values of coercivity (664–926 Oe) of these nanomaterials suggest their use in longitudinal recording media. - Highlights: • Micro-emulsion route was used to synthesize Ba{sub 2}NiCoRE{sub x}Fe{sub 28−x}O{sub 46} ferrites. • The crystallite size was found

First Calorimetric Measurement of OI-line in the Electron Capture Spectrum of $^{163}$Ho

CERN Document Server

Ranitzsch, P. C. -O.; Wegner, M.; Kempf, S.; Fleischmann, A.; Enss, C.; Gastaldo, L.; Herlert, A.; Johnston, K.

2014-01-01

The isotope $^{163}$Ho undergoes an electron capture process with a recommended value for the energy available to the decay, $Q_{\\rm EC}$, of about 2.5 keV. According to the present knowledge, this is the lowest $Q_{\\rm EC}$ value for electron capture processes. Because of that, $^{163}$Ho is the best candidate to perform experiments to investigate the value of the electron neutrino mass based on the analysis of the calorimetrically measured spectrum. We present for the first time the calorimetric measurement of the atomic de-excitation of the $^{163}$Dy daughter atom upon the capture of an electron from the 5s shell in $^{163}$Ho, OI-line. The measured peak energy is 48 eV. This measurement was performed using low temperature metallic magnetic calorimeters with the $^{163}$Ho ion implanted in the absorber. We demonstrate that the calorimetric spectrum of $^{163}$Ho can be measured with high precision and that the parameters describing the spectrum can be learned from the analysis of the data. Finally, we dis...

Mixed phosphates of the Na3PO4 - LnPO4 systems

International Nuclear Information System (INIS)

Slivko, T.A.; Smirnova, I.N.; Zimina, G.V.; Spiridonov, F.M.; Chudinova, N.N.

2002-01-01

The phase relationships in the systems Na 3 PO 4 - LnPO 4 (subsolidus 950 Deg C cross-sections), where Ln=Sm, Eu, Tb, Dy, Ho, Tm, Yb, Lu, were studied by X-ray analysis. Reactions of the components were deduced, formed phases were separated and identified. The Na 6 Ln 3 (PO 4 ) 5 (Ln=Dy, Ho, Tm), Na 3 Ln 2 (PO 4 ) 3 (Ln=Tm, Yb, Lu) compounds and phases of the unstable composition Na 6+x Ln 3-x/3 (PO 4 ) 5 (Ln=Yb, Lu, 0 ≤ x ≤ 1.5) were detected for the first time. In all systems the existence of the Na 3-x Ln x/3 PO 4 unstable composition phase on the basis of the high temperature modification of sodium phosphate (sp. gr. Fm3m) is established, suggesting that stabilization of this modification by rare earth ions is possible [ru

The ternary rare earth ruthenium gallides R3Ru4Ga15 (R=Y, Tb-Er) with a new structure type, a further example of a recently recognized large family of structures

International Nuclear Information System (INIS)

Schlueter, Martin; Jeitschko, Wolfgang

2003-01-01

The title compounds were prepared by reaction of the elemental components at high temperature. They crystallize with a new orthorhombic structure type which was determined from single-crystal diffractometer data of Ho 3 Ru 4 Ga 15 : Pnma, a=871.7(1) pm, b=956.4(1) pm, c=1765.9(3) pm, Z=4, R=0.040 for 1039 structure factors and 114 variable parameters. The structure may be viewed as consisting of two kinds of atomic layers, although atomic bonding within and between the layers is comparable strength, as can be judged from the near-neighbor environments, where all of the 15 atomic sites have high coordination numbers. One kind of atomic layers (A) contains all of the holmium and additional gallium atoms in the ratio Ho:Ga=3:5 with a unit mesh content of 2Ho 3 Ga 5 ; these layers are flat. The other layers (B) consist of sheets of corner- and edge-sharing condensed RuGa 6 octahedra, which are extremely compressed resulting in a hexagonal close-packed, puckered net with a Ru:Ga ratio of 2:5 and a unit mesh content of 4Ru 2 Ga 5 . These nets alternate in the sequence ABAB, ABAB, thus yielding the formula 4Ho 3 Ga 5 ·8Ru 2 Ga 5 =4Ho 3 Ru 4 Ga 15 . Similar layers are observed in the structures of Y 2 Co 3 Ga 9 , Gd 3 Ru 4 Al 12 , Er 4 Pt 9 Al 24 , CeOsGa 4 , CaCr 2 Al 10 , and the four stacking variants with the compositions TbRe 2 Al 10 , DyRe 2 Al 10 , YbFe 2 Al 10 , and LuRe 2 Al 10

Theory of Random Anisotropic Magnetic Alloys

DEFF Research Database (Denmark)

Lindgård, Per-Anker

1976-01-01

A mean-field-crystal-field theory is developed for random, multicomponent, anisotropic magnetic alloys. It is specially applicable to rare-earth alloys. A discussion is given of multicritical points and phase transitions between various states characterized by order parameters with different...... spatial directions or different ordering wave vectors. Theoretical predictions based on known parameters for the phase diagrams and magnetic moments for the binary rare-earth alloys of Tb, Dy, Ho, and Er, Tb-Tm, Nd-Pr, and pure double-hcp Nd agree qualitatively with the experimental observations...... fluctuation corrections in the mean-field results is also discussed....

Magnetic structures: neutron diffraction studies

International Nuclear Information System (INIS)

Bouree-Vigneron, F.

1990-01-01

Neutron diffraction is often an unequivocal method for determining magnetic structures. Here we present some typical examples, stressing the sequence through experiments, data analysis, interpretation and modelisation. Two series of compounds are chosen: Tb Ni 2 Ge 2 and RBe 13 (R = Gd, Tb, Dy, Ho, Er). Depending on the nature of the elements, the magnetic structures produced can be commensurate, incommensurate or even show a transition between two such phases as a function of temperature. A model, taking magnetic exchange and anisotropy into account, will be presented in the case of commensurate-incommensurate magnetic transitions in RBe 13

Structure, magnetism, and transport of single-crystalline R NiSi3 (R = Y, Gd-Tm, Lu)

Science.gov (United States)

Arantes, Fabiana R.; Aristizábal-Giraldo, Deisy; Masunaga, Sueli H.; Costa, Fanny N.; Ferreira, Fabio F.; Takabatake, Toshiro; Mendonça-Ferreira, Leticie; Ribeiro, Raquel A.; Avila, Marcos A.

2018-04-01

We report on the physical properties of the intermetallic series R NiSi3 (R =Y , Gd-Tm, Lu). High quality single crystals with platelike morphology were grown using the Sn flux method. X-ray powder diffraction data show that this series crystallizes in the orthorhombic space group Cmmm, and Laue patterns indicate that the b axis remains perpendicular to the plane of the plates. Magnetization measurements show anisotropic antiferromagnetic ground states for R = Gd-Tm with Néel temperatures ranging from TN=2.6 K (TmNiSi3) up to 32.2 K (TbNiSi3), as well as metamagnetic transitions that in some cases appear together with hysteresis (TbNiSi3,DyNiSi3, and HoNiSi3). The easy axis changes from a axis to b axis on going from R = Gd-Ho to R = Er-Tm. All transitions from antiferromagnetic to paramagnetic states are clearly marked by sharp peaks in specific heat as well as in the derivative of resistivity measurements, which show metallic temperature dependence for all compounds and residual values in the range of 1 μ Ω cm . DyNiSi3 has two close phase transitions, while HoNiSi3 presents distinct critical temperatures for applied fields in the a or c directions (10.4 and 6.3 K, respectively), pointing to possible component-specific ordering of the local magnetic moments.

Characterization of low temperature metallic magnetic calorimeters having gold absorbers with implanted 163Ho ions

Science.gov (United States)

Gastaldo, L.; Ranitzsch, P. C.-O.; von Seggern, F.; Porst, J.-P.; Schäfer, S.; Pies, C.; Kempf, S.; Wolf, T.; Fleischmann, A.; Enss, C.; Herlert, A.; Johnston, K.

2013-05-01

For the first time we have investigated the behavior of fully micro-fabricated low temperature metallic magnetic calorimeters (MMCs) after undergoing an ion-implantation process. This experiment had the aim to show the possibility to perform a high precision calorimetric measurement of the energy spectrum following the electron capture of 163Ho using MMCs having the radioactive 163Ho ions implanted in the absorber. The isotope 163Ho decays through electron capture to 163Dy and features the smallest known QEC value. This peculiarity makes 163Ho a very interesting candidate to investigate the value of the electron neutrino mass by the analysis of the energy spectrum. The implantation of 163Ho ions was performed at ISOLDE-CERN. The performance of a detector that underwent an ion-implantation process is compared to the one of a detector without implanted ions. The results show that the implantation dose of ions used in this experiment does not compromise the properties of the detector. Moreover the performance of the detector prototype having the 163Ho ions implanted in the absorber is already close to the requirements needed for an experiment with sub-eV sensitivity to the electron neutrino mass. Based on these results, an optimized detector design for future 163Ho experiments is presented.

Characterization of low temperature metallic magnetic calorimeters having gold absorbers with implanted 163Ho ions

International Nuclear Information System (INIS)

Gastaldo, L.; Ranitzsch, P.C.-O.; Seggern, F. von; Porst, J.-P.; Schäfer, S.; Pies, C.; Kempf, S.; Wolf, T.; Fleischmann, A.; Enss, C.; Herlert, A.; Johnston, K.

2013-01-01

For the first time we have investigated the behavior of fully micro-fabricated low temperature metallic magnetic calorimeters (MMCs) after undergoing an ion-implantation process. This experiment had the aim to show the possibility to perform a high precision calorimetric measurement of the energy spectrum following the electron capture of 163 Ho using MMCs having the radioactive 163 Ho ions implanted in the absorber. The isotope 163 Ho decays through electron capture to 163 Dy and features the smallest known Q EC value. This peculiarity makes 163 Ho a very interesting candidate to investigate the value of the electron neutrino mass by the analysis of the energy spectrum. The implantation of 163 Ho ions was performed at ISOLDE-CERN. The performance of a detector that underwent an ion-implantation process is compared to the one of a detector without implanted ions. The results show that the implantation dose of ions used in this experiment does not compromise the properties of the detector. Moreover the performance of the detector prototype having the 163 Ho ions implanted in the absorber is already close to the requirements needed for an experiment with sub-eV sensitivity to the electron neutrino mass. Based on these results, an optimized detector design for future 163 Ho experiments is presented

Single-molecule magnet behavior in 2,2’-bipyrimidine-bridged dilanthanide complexes

Directory of Open Access Journals (Sweden)

Wen Yu

2016-01-01

Full Text Available A series of 2,2’-bipyrimidine-bridged dinuclear lanthanide complexes with the general formula [Ln(tmhd3]2bpm (tmhd = 2,2,6,6-tetramethyl-3,5-heptanedionate, bpm = 2,2’-bipyrimidine, Ln = Gd(III, 1; Tb(III, 2; Dy(III, 3; Ho(III, 4 and Er(III, 5 has been synthesized and characterized. Sublimation of [Tb(tmhd3]2bpm onto a Au(111 surface leads to the formation of a homogeneous film with hexagonal pattern, which was studied by scanning tunneling microscopy (STM. The bulk magnetic properties of all complexes have been studied comprehensively. The dynamic magnetic behavior of the Dy(III and Er(III compounds clearly exhibits single molecule magnet (SMM characteristics with an energy barrier of 97 and 25 K, respectively. Moreover, micro-SQUID measurements on single crystals confirm their SMM behavior with the presence of hysteresis loops.

Structure, photo- and triboluminescence of the lanthanoid dibenzoylmethanates: HNEt3[Ln(dbm)4

International Nuclear Information System (INIS)

Akerboom, Sebastiaan; Meijer, Michael S.; Siegler, Maxime A.; Fu, Wen Tian; Bouwman, Elisabeth

2014-01-01

A series of lanthanoid coordination compounds with the general formula HNEt 3 [Ln(dbm) 4 ] (Ln=La, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb; dbm=dibenzoylmethanate) has been prepared and characterized. In addition, single crystals with Ln=La, Nd and Sm were obtained. Single crystal X-ray diffraction studies reveal that the compounds with Ln=La and Nd crystallize in the P2 1 /c space group, while the Sm-compound crystallizes in the Pc space group. Based on powder XRD data, the compounds with Ln=Eu–Yb can be described with a monoclinic cell. Photoluminescence studies indicate that compounds with Ln=Sm and Eu exhibit bright photoluminescence characteristic of the lanthanoid ion upon excitation in the near UV range. Furthermore, HNEt 3 [Sm(dbm) 4 ] has been identified as a novel triboluminescent compound. -- Highlights: • The compounds HNEt 3 [Ln(dbm) 4 ], Ln=La, Nd, Sm, Eu, Tb, Dy, Ho Er, Tm, and Yb, have been prepared and their photophysical properties have been studied. • Crystal structures of HNEt 3 [La(dbm) 4 ], HNEt 3 [Nd(dbm) 4 ] and HNEt 3 [Sm(dbm) 4 ] are reported for the first time. • A novel, brightly triboluminescent Sm compound is reported

Synthesis, thermal and magnetic properties of RE-diborides

Energy Technology Data Exchange (ETDEWEB)

Novikov, V.V., E-mail: vvnovikov@mail.ru [Training-Research Center ' Bryansk Physical Laboratory' , Petrovsky Bryansk State University, 14, Bezhitskaya St, 241036 Bryansk (Russian Federation); Matovnikov, A.V. [Training-Research Center ' Bryansk Physical Laboratory' , Petrovsky Bryansk State University, 14, Bezhitskaya St, 241036 Bryansk (Russian Federation); Volkova, O.S. [Lomonosov Moscow State University, GSP-1, Leninskie Gory, 119991 Moscow (Russian Federation); Vasil' ev, A.N., E-mail: vasil@mig.phys.msu.ru [Lomonosov Moscow State University, GSP-1, Leninskie Gory, 119991 Moscow (Russian Federation)

2017-04-15

Techniques of synthesis of RE diborides (RB{sub 2}) are developed (R=Tb, Dy, Ho, Er, Lu). Temperature dependence of magnetisation, a heat capacity, a lattice parameters of diborides in the range of 2–300 K are measured. According to joint calorimetric and X-ray research the analysis of a phonon component of a heat capacity and thermal expansion of RE-diborides is carried out by Debye-Einstein's models, the parameters of the model are determined. The change of magnetisation of the ferromagnetic RB{sub 2} compounds with growth of temperature caused by violation of ordering in the system of the atomic magnetic moments is compared with the change of entropy of a magnetic subsystem calculated from calorimetric data. Analytical expansion for calculation of a magnetic component of a heat capacity by RB{sub 2} magnetisation data at the temperatures of 2–300 K is obtained. - Highlights: • 1 Techniques of synthesis of RE diborides (RB{sub 2}) are developed (R=Tb, Dy, Ho, Er, Lu). • 2 Temperature dependence of magnetisation of diborides at 2–300 K is determined. • 3 Calculation method of RB{sub 2} magnetic heat capacity from magnetic data is obtained.

Search for and study of linking transitions between super- and normal deformed wells in the {sup 151}Tb nucleus; Recherche et etude de transitions de liaison entre les puits super- et normalement deformes dans le noyau {sup 151}Tb

Energy Technology Data Exchange (ETDEWEB)

Robin, J

2003-12-01

While the superdeformation phenomenon has been observed many times in different mass regions, the excitation energy and angular momentum are not known for most of the superdeformed bands, mainly in the A {approx} 150 mass region. We have thus undertaken the search for and study of linking transitions between super and normal deformed potential wells in the Tb{sup 151} nucleus with the EUROBALL-IV spectrometer based at the subatomic research institute of Strasbourg. This nucleus presents the peculiarity of having an excited superdeformed band identical to the yrast one of Dy{sup 152}, which has recently been linked to normal deformed states. As the Dy{sup 152} nucleus exhibits a shape coexistence in the first potential well, we have also searched for collective rotational bands with prolate but moderate shape, coexisting with the oblate structure of Tb{sup 151}. The discovery of new superdeformed bands in the Tb{sup 151,152} isotopes, the extension to lower and higher spins of the previously known bands, and mean field calculations with a deformed Woods-Saxon potential have contributed to improve our knowledge as well as raise new questions on the orbitals configuration assignments of these bands. (author)

Hexagonal perovskites with cationic vacancies. 1. Compounds of the type Ba/sub 2/Bsub(1/3)sup(III) vacantsub(2/3) Resup(VII)O/sub 6/

Energy Technology Data Exchange (ETDEWEB)

Kemmler-Sack, S; Jooss, I [Tuebingen Univ. (Germany, F.R.). Inst. fuer Chemie

1978-04-01

Compounds of type Ba/sub 2/Bsub(1/3)sup(III)vacantsub(2/3)Resup(VII)O/sub 6/ are formed with Bsup(III) = Sm-Gd, Ho-Lu, Y, Sc, In (yellow); Tb (black-brown); Dy (yellow-orange). They crystallize with Bsup(III) = Sm-Lu, Y and Sc in a rhombohedral layer structure of 12 L-type (space group R3m; sequence: cchhcchhcchh) with 6 formula units in the unit cell.

Magnetic nanoparticles formed in glasses co-doped with iron and larger radius elements

OpenAIRE

Edelman , Irina; Ivanova , Oxana; Ivantsov , Ruslan; Velikanov , D.; Zabluda , V.; Zubavichus , Y.; Veligzhanin , A.; Zaikovskiy , V.; Stepanov , S.; Artemenko , Alla; Curély , Jacques; Kliava , Janis

2012-01-01

International audience; A new type of nanoparticle-containing glasses based on borate glasses co-doped with low contents of iron and larger radius elements, Dy, Tb, Gd, Ho, Er, Y, and Bi, is studied. Heat treatment of these glasses results in formation of magnetic nanoparticles, radically changing their physical properties. Transmission electron microscopy and synchrotron radiation-based techniques: x-ray diffraction, extended x-ray absorption fine structure, x-ray absorption near-edge struct...

Yttrium interaction with iron family metals

International Nuclear Information System (INIS)

Kharchenko, O.I.; Bodak, O.I.; Gladyshevskij, E.I.

1977-01-01

X-ray and micro-structure analyses were used to study ternary systems Y-Fe-Co, Y-Fe-Ni, Y-Co-Ni and phase equilibrium diagrams were plotted. The formation of a compound YCosub(0.8-0.38)Nisub(0.2-0.62) with a type MoB structure (a=3.946, c=20.85 A) was detected. Isostructural compounds with other rare earth metals (R) were found (R-Cd, Tb, Dy, Ho, Er, Tm)

Neutron scattering study on R{sub 2}PdSi{sub 3} (R=Ho,Er,Tm) compounds

Energy Technology Data Exchange (ETDEWEB)

Tang, Fei

2010-12-14

Previous studies on the family of inter-metallic rare-earth compounds R{sub 2}PdSi{sub 3} revealed multifaceted magnetic properties, for instance, spin-glass like behavior. Experimental observations include: Signs of a crystallographic superstructure, complicated magnetic structures both in zero field and in applied magnetic fields as well as a generic phase in applied fields for compounds in the series with the heavy rare-earths R=Gd, Tb, Dy, Ho, Er and Tm. This thesis expands the studies on the magnetic properties of R{sub 2}PdSi{sub 3} employing mainly neutron scattering on single crystals with the focus on the compounds with R=Ho, Er and Tm. A detailed analysis of the crystallographic superstructure using modulation wave approach and group theory is presented. The resulting structure implies the existence of two different rare-earth sites with reduced symmetry and an arrangement of the different sites according to sequences as determined by the superstructure. It is shown that the reduced symmetry of the rare-earth sites is explicitly observed in the energy spectra of inelastic neutron scattering. The results on the magnetic structures and excitations are shown and discussed in the framework of the superstructure model. Specifically the generic phase in applied fields is interpreted as a direct consequence of the crystallographic superstructure. It is rather unusual that a crystallographic superstructure is playing such a decisive, and through the field dependence also tunable role in determining the magnetic properties as observed in R{sub 2}PdSi{sub 3}. The mediating interactions between the crystallographic part and the magnetic part of the system are discussed. (orig.)

Search for and study of linking transitions between super- and normal deformed wells in the 151Tb nucleus

International Nuclear Information System (INIS)

Robin, J.

2003-12-01

While the superdeformation phenomenon has been observed many times in different mass regions, the excitation energy and angular momentum are not known for most of the superdeformed bands, mainly in the A ∼ 150 mass region. We have thus undertaken the search for and study of linking transitions between super and normal deformed potential wells in the Tb 151 nucleus with the EUROBALL-IV spectrometer based at the subatomic research institute of Strasbourg. This nucleus presents the peculiarity of having an excited superdeformed band identical to the yrast one of Dy 152 , which has recently been linked to normal deformed states. As the Dy 152 nucleus exhibits a shape coexistence in the first potential well, we have also searched for collective rotational bands with prolate but moderate shape, coexisting with the oblate structure of Tb 151 . The discovery of new superdeformed bands in the Tb 151,152 isotopes, the extension to lower and higher spins of the previously known bands, and mean field calculations with a deformed Woods-Saxon potential have contributed to improve our knowledge as well as raise new questions on the orbitals configuration assignments of these bands. (author)

Rotational and translational distortions of the crystal structure of the Sr2HrRuO6 (Hr = Ho, Dy, Gd, Eu) complex perovskites

International Nuclear Information System (INIS)

Triana, C.A.; Landínez Téllez, D.A.; Roa-Rojas, J.

2013-01-01

Sr 2 HrRuO 6 (Hr = Ho, Dy, Gd, Eu) complex perovskites were synthesized through the high-temperature solid-state reaction method, and their crystal structures were analyzed in detail as a function of the Hr-cation ionic radius. Results of powder XRD pattern measurement and Rietveld analysis of the experimental profiles show that the Sr 2 HrRuO 6 compounds crystallize in a monoclinic distorted perovskite-like structure, P2 1 /n (#14) space group, where the unit cell parameters are related to the primitive unit cell a p by a≈√(2)a p , b≈√(2)a p and c ≈ 2a p . The structures show an alternate distribution of the Ru 5+ (2d: 0.5, 0, 0) and Hr 3+ (2c: 0, 0.5, 0) making up RuO 6 and HrO 6 octahedra alternatively arranged in two interleaving fcc sublattices, where the O(1), O(2), and O(3) ions are localized at the corner of the octahedral, while the Sr 2+ is located at the A-site, occupying the cavities built by the corner-sharing octahedra with Wyckoff position 4e. Due to the existence of mismatched ionic sizes between the ionic radii of the Sr 2 HrRuO 6 compounds, the HrO 6 and RuO 6 octahedra are constrained to tilting around the [111] c , [001] c , and [110] c cubic directions so as to optimize the Sr–O inter-atomic bond lengths, tending to rotate the structure in order to fix the Ru 5+ and Hr 3+ ions on the M′ and M″ sites of the complex perovskites. The cell parameters a, b, and c, the inter-atomic bond angles, the inter-atomic bond lengths, and the tilting angles increase as the Hr-cation ionic radius increases. The mismatch that exists in the Sr 2 HrRuO 6 ionic radius produces a large distortion from the ideal cubic symmetry. The pure perovskite-like phase of Sr 2 HrRuO 6 is thermodynamically and kinetically stable at high temperatures above 1420 K, where it is entirely governed by the average size of the Hr 3+ and Ru 5+ cations. Highlights: ► Crystal structure of Sr 2 HrRuO 6 (Hr = Ho, Dy, Gd, Eu) as a function of Hr ionic radius. ► XRD

The phase transition of the incommensurate phases β-Ln(PO3)3(Ln=Y,Tb...Yb), crystal structures of α-Ln(PO3)3(Ln=Y,Tb...Yb) and Sc(PO3)3

International Nuclear Information System (INIS)

Hoeppe, Hennig A.

2009-01-01

The incommensurately modulated room-temperature phases β-Ln(PO 3 ) 3 (Ln=Y,Tb...Yb) undergo a topotactic phase transition monitored by vibrational spectroscopy below 180 K leading to α-Ln(PO 3 ) 3 (Ln=Y,Dy...Yb), above 200 K the incommensurate phases are reobtained. The low-temperature phases exhibit a new structure type (α-Dy(PO 3 ) 3 ,P2 1 /c,Z=12,a=14.1422(6),b=20.0793(9),c=10.1018(4)A, β=127.532(3) 0 ). α-Tb(PO 3 ) 3 is isotypic with Gd(PO 3 ) 3 (α-Tb(PO 3 ) 3 ,I2/a,Z=16,a=25.875(6),b=13.460(3),c=10.044(2)A, β=119.13(3) 0 ). The symmetry relations between the involved phases of the phase transition are discussed. The crystal structure of Sc(PO 3 ) 3 is isotypic with that of Lu(PO 3 ) 3 and C-type phosphates. The polyphosphates consist of infinite zig-zag chains of corner-sharing PO 4 tetrahedra, the cations are coordinated sixfold in an almost octahedral arrangement. To confirm the quality of the determined crystal structures the deviation of the phosphate tetrahedra from ideal symmetry was determined and discussed. - Abstract: Basic structure from which all crystal structures of the late lanthanoids' polyphosphates at room temperature and below can be derived.

Isomer spectroscopy of neutron-rich 168 Tb 103

Energy Technology Data Exchange (ETDEWEB)

Gurgi, L. A.; Regan, P. H.; Söderström, P. -A.; Watanabe, H.; Walker, P. M.; Podolyák, Zs.; Nishimura, S.; Berry, T. A.; Doornenbal, P.; Lorusso, G.; Isobe, T.; Baba, H.; Xu, Z. Y.; Sakurai, H.; Sumikama, T.; Catford, W. N.; Bruce, A. M.; Browne, F.; Lane, G. J.; Kondev, F. G.; Odahara, A.; Wu, J.; Liu, H. L.; Xu, F. R.; Korkulu, Z.; Lee, P.; Liu, J. J.; Phong, V. H.; Yag, A.; Zhang, G. X.; Alharbi, T.; Carroll, R. J.; Chae, K. Y.; Dombradi, Zs.; Estrade, A.; Fukuda, N.; Griffin, C.; Ideguchi, E.; Inabe, N.; Kanaoka, H.; Kojouharov, I.; Kubo, T.; Kubono, S.; Kurz, N.; Kuti, I.; Lalkovski, S.; Lee, E. J.; Lee, C. S.; Lotay, G.; Moon, C. -B.; Nishizuka, I.; Nita, C. R.; Patel, Z.; Roberts, O. J.; Schaffner, H.; Shand, C. M.; Suzuki, H.; Takeda, H.; Terashima, S.; Vajta, Zs.; Yoshida, S.; Valiente-Dòbon, J. J.

2017-11-01

In-flight fission of a 345 MeV per nucleon 238U primary beam on a 2 mm thick 9Be target has been used to produce and study the decays of a range of neutron-rich nuclei centred around the doubly mid-shell nucleus 170Dy at the RIBF Facility, RIKEN, Japan. The produced secondary fragments of interest were identified event-by-event using the BigRIPS separator. The fragments were implanted into the WAS3ABI position sensitive silicon active stopper which allowed pixelated correlations between implants and their subsequent β-decay. Discrete γ-ray transitions emitted following decays from either metastable states or excited states populated following beta decay were identified using the 84 coaxial high-purity germanium (HPGe) detectors of the EURICA spectrometer, which was complemented by 18 additional cerium-doped lanthanum bromide (LaBr3) fast-timing scintillation detectors from the FATIMA collaboration. This paper presents the internal decay of a metastable isomeric excited state in the odd-odd nucleus 168Tb, which corresponds to a single proton-neutron hole configuration in the valence maximum nucleus 170Dy. These data represent the first information on excited states in this nucleus, which is the most neutron-rich odd-odd isotope of terbium (Z=65) studied to date. Nilsson configurations associated with an axially symmetric, prolate-deformed nucleus are proposed for the 168Tb ground state the observed isomeric state by comparison with Blocked BCS-Nilsson calculations.

Investigation of nuclei near N = 82 and Z = 64 VIA radioactive decay of high-spin isomers

International Nuclear Information System (INIS)

Toth, K.S.

1979-01-01

An island of very high spin isomers was found recently in neutron-deficient Gd-Lu nuclei near the N = 82 closed shell in (H.I.,xn) measurements. This exciting discovery has led to a large number of experiments trying to identify the structures of these isomers and the nuclei in which they occur. These attempts have been helped in many instances by available spectroscopic information at low excitation energies. A systematic investigation of the low-lying structure of nuclei near N = 82 and Z greater than or equal to 64 was carried out. Heavy-ion beams were used to produce proton-rich isotopes which were then transported, with the use of gas-jet systems, to shielded areas where singles and coincidence γ-ray measurements could be made. Earlier investigations dealt with the decay of terbium ( 146-149 Tb) and dysprosium ( 147-152 Dy) nuclei. During the past two years the research program was extended to holmium nuclides (A less than or equal to 152) produced in 10 B bombardments of samarium. Two new isotopes, 149 Ho and 148 Ho, were identified. The decay data of 21-s 149 Ho supplement in-beam results and locate the hg/ 2 neutron state in 149 Dy to be at 1091 keV. The most intense γ-ray associated with 9-s 148 Ho has an energy of 1688 keV. It is possibly the first-excited to ground-state transition in 148 Dy. Recent in-beam measurements have shown that the first-excited state in 146 Gd is, unespectedly, 3 - in contrast to doubly evenN = 82 nuclei below gadolinium where it is 2 + . It would be interesting to determine whether the 1688-keV level in 148 Dy, the next nucleus in this isotonic series, is 2reverse arrow or 3 - in character. 12 references

Cut-off frequency of magnetostrictive materials based on permeability spectra

International Nuclear Information System (INIS)

Meng Hao; Zhang Tianli; Jiang Chengbao

2012-01-01

The loss behavior and cut-off frequency of TbDyFe alloy and TbDyFe/epoxy composite have been investigated by measuring their permeability spectra. The loss factor of TbDyFe alloy increases exponentially as the frequency goes up, while it is almost unchanged for the TbDyFe/epoxy composite. The loss factor value for the TbDyFe composite is only 4.3% of that for the monolithic TbDyFe alloy at high frequency of 10 kHz under the peak magnetic induction of 10 mT. The cut-off frequency of TbDyFe/epoxy composite is 6800 kHz, 3 orders of magnitude larger than that of TbDyFe alloy. The cut-off frequency is found to be the ferromagnetic resonance frequency and can be calculated from Snoek's law. - Highlights: ► The cut-off frequency of TbDyFe alloy and TbDyFe/epoxy composite has been investigated. ► Permeability spectra are used to study loss behavior and cut-off frequency. ► A mathematic formula is deduced to predict the cut-off frequency. ► TbDyFe/epoxy composite presents high cut-off frequency of 6800 kHz.

Field-induced transitions in DySb

International Nuclear Information System (INIS)

Brun, T.O.; Lander, G.H.; Korty, F.W.; Kouvel, J.S.

1974-01-01

The NaCl-structured compound DySb, which in zero field transforms abruptly at T/sub N/ approximately 9.5 0 K to a Type-II antiferromagnetic (A) state with a nearly tetragonal lattice distortion, was previously found to exhibit rapid field-induced changes in magnetization at 1.5 0 K. The field-induced transitions in a DySb crystal have been studied by neutron diffraction and magnetization measurements in fields up to approximately 60 kOe applied parallel to each of the principal axes. In the broken bracket 100 broken bracket case, the transition from the A to an intermediate ferrimagnetic (Q) state is first-order at 4.2 0 K (critical field H/sub c/ approximately 21 kOe) but is continuous from approximately 6 0 K up to T/sub N/: as H/sub c/ → 0. The Q-to-paramagnetic (P) transition is rapid but continuous at 4.2 0 K (H/sub c/ approximately 40 kOe) and becomes broad as T/sub N/ is approached. In the broken bracket 110 broken bracket case the A-to-Q transition remains essentially first-order from 4.2 0 K (H/sub c/ approximately 15 kOe) up to T/sub N/; above T/sub N/ rapid P-to-Q transitions occur at very high fields. The magnetic structure of the Q state is found to be that of HoP. (U.S.)

Separation of lanthanides through hydroxyapatite; Separacion de lantanidos mediante hidroxiapatita

Energy Technology Data Exchange (ETDEWEB)

Garcia M, F.G

2006-07-01

With the objective of obtaining from an independent way to each one of the lanthanides {sup 151} Pm, {sup 161} Tb, {sup 166} Ho and {sup 177} Lu free of carrier and with high specific activities starting from the indirect irradiation via, it intends in this work to determine the viability of separation of the couples Nd/Pm, Dy/Ho, Gd/Tb and Yb/Lu, by means of ion exchange column chromatography, using hydroxyapatite (HAp) and fluorite like absorbent material in complexing media. It is important to mention that have registered separation studies among lanthanides of the heavy group with those of the slight group, using the same mass and, in comparison with this work, quantities different from the father were used and of the son, also, that the separation studies were carried out among neighboring lanthanides. In this investigation, it was determined the effect that its have the complexing media: KSCN, sodium tartrate, sodium citrate, EDTA and aluminon, their pH and concentration, in the adsorption of the lanthanides in both minerals, in order to determine the chromatographic conditions for separation of the couples Nd/Pm, Dy/Ho, Gd/Tb and Yb/Lu. The work consists of five chapters, in the first one they are presented a theoretical introduction of the characteristics more important of the lanthanides, the hydroxyapatite and the fluorite; in the second, it is deepened in the ion exchange, as well as the two techniques (XRD and High Vacuum Electron Microscopy) to make the characterization of LnCI{sub 3} (Ln = Nd, Gd, Dy or Yb) synthesized. The third chapter, it describes the methodology continued in our experimental work; in the room, its are presented the obtained results of the static and dynamic method to determine the viability of separation of neighboring lanthanides; and finally, the five chapter shows the conclusions. In this study, it is concludes that the separation among neighboring lanthanides cannot be carried out in the minerals and used media; because

Separation of lanthanides through hydroxyapatite

International Nuclear Information System (INIS)

Garcia M, F.G.

2006-01-01

With the objective of obtaining from an independent way to each one of the lanthanides 151 Pm, 161 Tb, 166 Ho and 177 Lu free of carrier and with high specific activities starting from the indirect irradiation via, it intends in this work to determine the viability of separation of the couples Nd/Pm, Dy/Ho, Gd/Tb and Yb/Lu, by means of ion exchange column chromatography, using hydroxyapatite (HAp) and fluorite like absorbent material in complexing media. It is important to mention that have registered separation studies among lanthanides of the heavy group with those of the slight group, using the same mass and, in comparison with this work, quantities different from the father were used and of the son, also, that the separation studies were carried out among neighboring lanthanides. In this investigation, it was determined the effect that its have the complexing media: KSCN, sodium tartrate, sodium citrate, EDTA and aluminon, their pH and concentration, in the adsorption of the lanthanides in both minerals, in order to determine the chromatographic conditions for separation of the couples Nd/Pm, Dy/Ho, Gd/Tb and Yb/Lu. The work consists of five chapters, in the first one they are presented a theoretical introduction of the characteristics more important of the lanthanides, the hydroxyapatite and the fluorite; in the second, it is deepened in the ion exchange, as well as the two techniques (XRD and High Vacuum Electron Microscopy) to make the characterization of LnCI 3 (Ln = Nd, Gd, Dy or Yb) synthesized. The third chapter, it describes the methodology continued in our experimental work; in the room, its are presented the obtained results of the static and dynamic method to determine the viability of separation of neighboring lanthanides; and finally, the five chapter shows the conclusions. In this study, it is concludes that the separation among neighboring lanthanides cannot be carried out in the minerals and used media; because practically these lanthanides

High coercivity rare earth-transition metal magnets

International Nuclear Information System (INIS)

Croat, J.J.

1982-01-01

Ferromagnetic compositions having intrinsic magnetic coercivities at room temperature of at least 1,000 Oersteds are formed by the controlled quenching of molten rare earth-transition metal alloys. Hard magnets may be inexpensively formed from the lower atomic weight lanthanide elements and iron. The preferable compositions lie within: at least one of Fe, Ni, Co; 20 - 70 atomic percent: at least one of Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Y; 80 - 30 atomic percent. (author)

n-aminobenzoates of rare earths

International Nuclear Information System (INIS)

Efremova, G.I.; Buchkova, R.T.; Lapitskaya, A.V.; Pirkes, S.B.

1977-01-01

N-aminobenzoates of r.e.e. have been synthesized. Their composition corresponds to the general formula Me(C 6 H 4 NH 2 COO) 3 xnH 2 O, where Me stands for La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; n=1.2. The compounds obtained are identified by chemical analysis and roentgenographically. Their solubility products, which are values of the order of 10 -9 -10 -10 , are determined

Optical and magneto-optical properties of single crystals of RFe{sub 2} (R = Gd, Tb, Ho, and Lu) and GdCo{sub 2} intermetallic compounds

Energy Technology Data Exchange (ETDEWEB)

Lee, S.J.

1999-02-12

The author has studied the diagonal and off-diagonal optical conductivity of RFe{sub 2}(R = Gd, Tb, Ho, Lu) and GdCo{sub 2} single crystals grown by the flux method. Using spectroscopic ellipsometry the author has measured the dielectric function from 1.5 to 5.5 eV. The magneto-optical Kerr spectrometer at temperatures between 7 and 295 K and applied magnetic fields between 0.5 to 1.6 T. The apparatus and calibration method are described in detail. Using magneto-optical data and optical constants he derives the experimental value of the off-diagonal conductivity components. Theoretical calculations of optical conductivities and magneto-optical parameters were performed using the tight binding-linear muffin tin orbitals method within the local spin density approximation. He applied this TB-LMTO method to LuFe{sub 2}. The theoretical results obtained agree well with the experimental data. The oxidation effects on the diagonal part of the optical conductivity were considered using a three-phase model. The oxidation effects on the magneto-optical parameters were also considered by treating the oxide layer as a nonmagnetic thin transparent layer. These corrections change not only the magnitude but also the shape of the optical conductivity and the magneto-optical parameters.

Crystal structure and magnetic properties of Tb6FeSb2

International Nuclear Information System (INIS)

Cai Gemei; Zhang Jiliang; He Wei; Qin Pingli; Zeng Lingmin

2006-01-01

The crystal structure and magnetic properties of Tb 6 FeSb 2 has been investigated for the first time. The compound crystallizes in the hexagonal, space group P6-bar 2m (No. 189) with the Ho 6 FeSb 2 structure type and lattice parameters a=8.1942(5)A, c=4.1758(3)A, z=1 and D calc =8.564g/cm 3 . Its magnetic properties were measured between 85 and 420K. The Curie temperature T c =256K was obtained using the method of intersecting tangents, and the effective paramagnetic moment was μ eff =9.32μ B per Tb atom

Studies on the electrochemical behavior of heavy lanthanide ions and the synthesis, characterization of heavy metal chelate complexes

International Nuclear Information System (INIS)

Kang, Sam Woo; Chang, Choo Hwan; Son, Byung Chan; Suh, Moo Yul; Kim, Chae Kyun

1991-01-01

Electrochemical behavior of some heavy lanthanide ions(Gd 3+ , Tb 3+ , Dy 3+ , Ho 3+ , Er 3+ , Tm 3+ , Yb 3+ and Lu 3+ ) in various supporting electrolytes has been investigated by dc polarography, differential pulse polarography and cyclic voltammetry. The peak potentials and the peak currents, their dependency on the concentration and pH effects, the reversibility of the electrode reactions are described. The reduction of Gd 3+ , Tb 3+ , Dy 3+ , Ho 3+ , Er 3+ , Tm 3+ and Lu 3+ ions in 0.1M lithium chloride solution proceeds by a three-electron change directly to the metallic state, whereas the reduction of Yb 3+ proceeds by a one-electron change followed by a two-electron change. It was found that, in differential pulse polarography and cyclic voltammetry, the peak potential, peak current and current function showed constant value in the pH range of 4.0-6.0 by varying pH and scan rates. And also the current function is found to decrease as the sweep rate is increased when the pH reaches 4.0. This fact may indicate a chemical reaction coupled with the electrochemical reaction at lower pH values(pH 3+ ion is possible to determine voltammetrically within the error of ±3.5% in the presence of other competitive lanthanide ions. (Author)

Molecular assembly and magnetic dynamics of two novel Dy6 and Dy8 aggregates.

Science.gov (United States)

Guo, Yun-Nan; Chen, Xiao-Hua; Xue, Shufang; Tang, Jinkui

2012-04-02

Complexation of dysprosium(III) with the heterodonor chelating ligand o-vanillin picolinoylhydrazone (H(2)ovph) in the presence of a carbonato ligand affords two novel Dy(6) and Dy(8) clusters, namely, [Dy(6)(ovph)(4)(Hpvph)(2)Cl(4)(H(2)O)(2)(CO(3))(2)]·CH(3)OH·H(2)O·CH(3)CN (2) and [Dy(8)(ovph)(8)(CO(3))(4)(H(2)O)(8)]·12CH(3)CN·6H(2)O (3). Compound 2 is composed of three petals of the Dy(2) units linked by two carbonato ligands, forming a triangular prism arrangement, while compound 3 possesses an octanuclear core with an unprecedented tub conformation, in which Dy(ovph) fragments are attached to the sides of the carbonato core. The static and dynamic magnetic properties are reported and discussed. In the Dy(6) aggregate, three Dy(2) "skeletons", having been well preserved (see the scheme), contribute to the single-molecule-magnet behavior with a relatively slow tunneling rate, while the Dy(8) cluster only exhibits a rather small relaxation barrier.

Magnetic moments of high spin rotational states in 158Dy and 164Dy+

International Nuclear Information System (INIS)

Seiler-Clark, G.

1983-09-01

For the study of their magnetic moments yrast states in 158 Dy and 164 Dy were excited via the multiple-Coulomb excitation by a 4.7 MeV/u 208 Pb beam. Hereby especially the question was of interest, how the one-particle effects in the nuclear structure in the region of the backbending anomaly in 158 Dy take effects on the g-factors of the high spin states in this region. The particle-γ angular correlations perturbed in the transient magnetic field during the passing of the excited Dy ions through a thin magnetized iron foil were measured. By the selective position-sensitive detection of Dy recoil ions and Pb projectiles under forward angles it was possible to determine additionally to the g-factors in the backbending region also g-factors in the spin region I 158 Dy and 164 Dy by detection of the particle-γ correlations precessing in the static hyperfine field after implantation in iron. The static hyperfine field was at the 4 + state in 164 Dy determined to B (Dy,Fe) = 245+-25 T. The g-factors were determined by comparison of the experimental results with calculations of the perturbed angular correlations by time-differential regarding of the population and de-excitation of the yrast states as well as by precession and hyperfine-relaxation effects during the flight of the Dy ions in the vacuum. (orig./HSI) [de

Level structure of 154Ho

Science.gov (United States)

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

2013-10-01

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

Heterogeneous bilayer films NiFe (Fe)-Dy: magnetic circular dichroism and Dy spin ordering

Energy Technology Data Exchange (ETDEWEB)

Markov, V.V. E-mail: ise@iph.krasn.ruise@iph.krasnoyarsk.su; Kesler, V.G.; Khudyakov, A.E.; Edelman, I.S.; Bondarenko, G.V

2001-08-01

Results of the magnetic circular dichroism (MCD) and Auger electron spectroscopy (AES) investigations in the 3d transition metal-Dy bi-layer films are presented. It is shown that even at room temperature the Dy layer makes a contribution to MCD of the bi-layer film, which corresponds to the MCD value in the single-layer Dy film measured below T{sub C}=85 K. According to the AES data there is no sharp interface between 3d and Dy layers in these films. Some amount of Ni and Fe atoms is dispersed in the Dy layer and some amount of Dy atoms is dispersed in the 3d layer. The comparison of the MCD and AES data allows one to suppose the Dy layer in the bi-layer films to be magnetically ordered at room temperature under the influence of the 3d-layer spin system. The influence spreads to long distances inside Dy layer through the 3d-ions dispersed in it.

Heterogeneous bilayer films NiFe (Fe)-Dy: magnetic circular dichroism and Dy spin ordering

International Nuclear Information System (INIS)

Markov, V.V.; Kesler, V.G.; Khudyakov, A.E.; Edelman, I.S.; Bondarenko, G.V.

2001-01-01

Results of the magnetic circular dichroism (MCD) and Auger electron spectroscopy (AES) investigations in the 3d transition metal-Dy bi-layer films are presented. It is shown that even at room temperature the Dy layer makes a contribution to MCD of the bi-layer film, which corresponds to the MCD value in the single-layer Dy film measured below T C =85 K. According to the AES data there is no sharp interface between 3d and Dy layers in these films. Some amount of Ni and Fe atoms is dispersed in the Dy layer and some amount of Dy atoms is dispersed in the 3d layer. The comparison of the MCD and AES data allows one to suppose the Dy layer in the bi-layer films to be magnetically ordered at room temperature under the influence of the 3d-layer spin system. The influence spreads to long distances inside Dy layer through the 3d-ions dispersed in it

Luminescence and magnetic properties of novel nanoparticle-sheathed 3D Micro-Architectures of Fe0.5R0.5(MoO4)1.5:Ln3+ (R = Gd3+, La3+), (Ln = Eu, Tb, Dy) for bifunctional application

Science.gov (United States)

Krishnan, Rajagopalan; Thirumalai, Jagannathan; Kathiravan, Arunkumar

2015-01-01

For the first time, we report the successful synthesis of novel nanoparticle-sheathed bipyramid-like and almond-like Fe0.5R0.5(MoO4)1.5:Ln3+ (R = Gd3+, La3+), (Ln = Eu, Tb, Dy) 3D hierarchical microstructures through a simple disodium ethylenediaminetetraacetic acid (Na2EDTA) facilitated hydrothermal method. Interestingly, time-dependent experiments confirm that the assembly-disassembly process is responsible for the formation of self-aggregated 3D architectures via Ostwald ripening phenomena. The resultant products are characterized by x-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), photoluminescence (PL), and magnetic measurements. The growth and formation mechanisms of the self-assembled 3D micro structures are discussed in detail. To confirm the presence of all the elements in the microstructure, the energy loss induced by the K, L shell electron ionization is observed in order to map the Fe, Gd, Mo, O, and Eu components. The photo luminescence properties of Fe0.5R0.5(MoO4)1.5 doped with Eu3+, Tb3+, Dy3+ are investigated. The room temperature and low temperature magnetic properties suggest that the interaction between the local-fields introduced by the magnetic Fe3+ ions and the R3+ (La, Gd) ions in the dodecahedral sites determine the magnetism in Fe0.5R0.5(MoO4)1.5:Eu3+. This work provides a new approach to synthesizing the novel Fe0.5R0.5(MoO4)1.5:Ln3+ for bi-functional magnetic and luminescence applications.

New lanthanide hydrogen phosphites LnH (P03H)2 2H20

International Nuclear Information System (INIS)

Durand, J.; Tijani, N.; Cot, L.; Loukili, M.; Rafiq, M.

1988-01-01

LnH ((P0 3 H) 2 2H 2 0 is prepared from lanthanide oxide and phosphorous acid with Ln = La, Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er or Tm. By thermal gravimetric analysis LnH (P0 3 H) 2 and LnH 2 P 2 0 5 (P0 3 H) 2 are obtained. The three salts are orthorhombic. Parameters and space groups are given for the three salts of each lanthanide. 4 tabs., 13 refs

High coercivity rare earth-transition metal magnets

International Nuclear Information System (INIS)

Croat, J.J.

1982-01-01

Ferromagnetic compositions having intrinsic magnetic coercivities at room temperature of at least 1,000 Oersteds are formed by the controlled quenching of molten rare earth -transition metal alloys. Hard magnets may be inexpensively formed from the lower atomic weight lanthanide elements and iron. The preferable compositions lie within: at least one of Fe, Ni, Co (20 to 70 atomic percent); and at least one of Ce, Pr, Na, Sm, Eu, Tb, Dy, Ho, Er, Tm, Y (80 to 30 atomic percent). (author)

Synthesis and investigation of rare earth tris-acetylacetonates addUcts with acetylaceoneimine

International Nuclear Information System (INIS)

Trembovetskij, G.V.; Smirnov, E.V.; Murav'eva, I.A.; Martynenko, L.I.

1983-01-01

Adducts of tris-acetylacetonates of pare earths With acetylacetonimine of the composition MA 3 x2L (M=La, Pr, Nd, Eu, Gd, Tb) and MA 3 XL (M=Dy, Ho, Er, Tm, Yb, LU) have been synthesized. The compounds prepared are studied using the methods of elemental analysis, IR spectroscopy, PMR spectroscopy, X-ray phase analysis. Volatile tris-acetylacetonates of the yttrium subgroUp rare earths have been prepared by thermal decomposition of MA 3 xL in vacuum

Crystal structure and magnetic state of pseudo-binary intermetallic compounds Ho(Cosub(1-x)Nisub(x))sub(5)

International Nuclear Information System (INIS)

Chuev, V.V.; Kelarev, V.V.; Pirogov, A.N.; Sidorov, S.K.; Koryakova, V.S.

1983-01-01

In the range of 1.8-1000 K intermetallic compounds Ho(Cosub(1-x)Nisub(x))sub(5) have been investigated neutronographically and roentgenographically. Crystal structure of two series of samples: HoCosub(5.5-5.5x)Nisub(5x) and HoCosub(5-5x)Nisub(5x) is studied. It is shown that Ni atoms mainly occupy positions 2c, Co atoms - positions 3g; coordinates of atoms and position occupation of TbCu 7 type structure are specified. Analysis of magnetic structure is made, angles of magnetic momenta orientation as to crystallographic axes are determined. Magnetic phase diagram is built. Concentrational dependences of sublattice magnetization: Msub(Ho)(x), Mdsub(2c)(x), Mdsub(3g)(x) are determined

Crystal shape-dependent magnetic susceptibility and Curie law crossover in the spin ices Dy2Ti2O7 and Ho2Ti2O7

International Nuclear Information System (INIS)

Bovo, L; Bramwell, S T; Jaubert, L D C; Holdsworth, P C W

2013-01-01

We present an experimental determination of the isothermal magnetic susceptibility of the spin ice materials Dy 2 Ti 2 O 7 and Ho 2 Ti 2 O 7 in the temperature range 1.8–300 K. The use of spherical crystals has allowed accurate correction for demagnetizing fields and allowed the true bulk isothermal susceptibility χ T (T) to be estimated. This has been compared against a theoretical expression based on a Husimi tree approximation to the spin ice model. Agreement between experiment and theory is excellent at T > 10 K, but systematic deviations occur below that temperature. Our results largely resolve an apparent disagreement between neutron scattering and bulk measurements that has been previously noted. They also show that the use of non-spherical crystals in magnetization studies of spin ice may introduce very significant systematic errors, although we note some interesting—and possibly new—systematics concerning the demagnetizing factor in cuboidal samples. Finally, our results show how experimental susceptibility measurements on spin ices may be used to extract the characteristic energy scale of the system and the corresponding chemical potential for emergent magnetic monopoles. (paper)

Elastic and Raman scattering of 8.5-11.4 MeV photons from 159Tb, 165Ho, and 237Np

International Nuclear Information System (INIS)

Bar-Noy, T.; Moreh, R.

1977-01-01

Differential cross sections for elastic and inelastic Raman scattering from the deformed heavy nuclei 159 Tb, 165 Ho and 237 Np were measured at five energies between 8.5 and 11.4 MeV. Angular distributions at four angles between 90 0 and 140 0 for both elastic and inelastic scattering at 9.0 and 11.4 MeV were also measured. The monoenergetic photons were obtained from thermal neutron capture in Ni and Cr. All the angular distributions and the elastic and Raman scattering at the higher energies are in good overall agreement with theoretical predictions. The theory is based on a modified simple rotator model of the giant resonance in which the effect of Delbrueck scattering was included. A trend of both the elastic and Raman scattering at lower energies to be stronger than expected are suggested by the data. However, the ratio between the Raman and elastic scattering seem to be in good agreement with theory throughout the whole energy range. This shows that there is no need to introduce a direct nonresonant component to the imaginary part of the elastic scattering amplitude to explain the experimental data. (Auth.)

Electronic and magnetic properties of R0.5A0.5MnO3 compounds (R=Gd, Dy, Ho, Er; A=Sr, Ca)

International Nuclear Information System (INIS)

Terai, T.; Sasaki, T.; Kakeshita, T.; Fukuda, T.; Saburi, T.; Kitagawa, H.; Kindo, K.; Honda, M.

2000-01-01

Electronic and magnetic properties of the perovskitelike compounds of R 0.5 A 0.5 MnO 3 (R=Gd, Dy, Ho, Er; A=Sr, Ca) have been studied by measuring lattice parameter, electrical resistivity, magnetic susceptibility, and magnetization. All the Sr-doped compounds show a transition from a paramagnetic insulator to a spin-glass-like insulator at T g , even though the manganite La 0.5 Ca 0.5 MnO 3 , with nearly the same tolerance factor t, have been shown by others, to have different transitions. On the other hand, all the Ca-doped compounds show a charge-ordering transition at T CO and show a transition from a paramagnetic insulator to a canted antiferromagnetic insulator and/or a spin-glass-like insulator at T CA below T CO . These transition temperatures decrease with decreasing t. In the compound of Gd 0.5 Ca 0.5 MnO 3 , the collapse of the charge ordering has been observed under a pulsed high magnetic field of 45 T at 4.2 K. On the other hand, in the compound of Gd 0.5 Sr 0.5 MnO 3 , the magnetization process depends on the strength of magnetic field. These electronic and magnetic properties depend not only on the tolerance factor but also the variance (second moment) of the A-site ion radii distribution

Studies of the energy transfer processes from Er3+ and Ho3+ to Nd3+, Tb3+ or Eu3+ in LiYF4 crystal and ZBLAN glass for the laser media optimization operating near 3μm region

International Nuclear Information System (INIS)

Jagosich, Fabio Henrique

2006-01-01

The energy transfer processes (ET) from the 4 I 13/2 ; 4 I 11/2 levels of Er 3+ and 5 I 6 levels of Ho 3+ ions in LiYF 4 (YLF) crystal and ZBLAN glass to Nd 3+ , Tb 3+ or Eu 3+ deactivators ions were studied. The micro parameters of these energy transfer processes were determined using the overlap integral method, and showed that Eu 3+ ion is the best deactivator of the first excited state of the Ho 3+ in YLF, and Nd 3+ is the best deactivator of the Er 3+ in YLF and ZBLAN materials. The 1.5 and 2.7μm emissions of Er 3+ and 2.1 and 2.9μm fluorescence of Ho 3+ were measured using short laser pulses excitations from a tunable OPO pumped 2w-Nd:YAG laser system. We proposed a criterion for discriminating the energy transfer processes assisted by excitation migration (diffusion or hopping) among donors. It was observed that diffusion model describes the ET process from the second excited state of the donor (Er 3+ or Ho 3+ ) independently of the C D-D /C D-A ratio, while the hopping model can describe the ET process involving the first excited state of donor. We proposed a modification of the hopping model in order to describe the experimental results for systems having C D-D /C D-A ≥ 10. Using the ET parameters, we determined that the best systems for laser action at 3μm are the Ho:Eu:YLF, Ho:Nd:YLF and Er:Nd:YLF systems. On the other hand, we found that Er 3+ doped (1.5 mol%) ZBLAN glasses, single and co-doped with Nd 3+ , Tb 3+ or Eu 3+ , do not show potential for laser action at 2.8μm. The up-conversion processes were studied in Er:YLF systems as a function of the Er 3+ concentration, and the excited state absorption (ESA) and up conversion by energy transfer (ETU) processes were discriminated using a time resolved fluorescence decays. It was observed that 980 nm is the most convenient wavelength for pumping the Er:YLF system for quasi cw laser operation at 2.8μm. The pump-probe technique was used to investigate the lifetime effects in Er:YLF system showing

A new TRISTAN thermal ion source

International Nuclear Information System (INIS)

Piotrowski, A.; Gill, R.L.; McDonald, D.C.

1984-01-01

A new thermal ion source with an integrated target which is heated by electron bombardment to a temperature of 2500 0 C has been developed for the TRISTAN on-line fission product mass separator at Brookhaven National Laboratory. Initial on-line tests demonstrated that this ion source can extend the range of accessible elements to the rare-earth region. Yields are presented for isotopes of Ce, Pr, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Ga, Ge, As, Y, Zr, Nb, In, Sn and Sb. (orig.)

DTA AND MOSSBAUER STUDIES IN RARE EARTH ORTHOFERRITES

Energy Technology Data Exchange (ETDEWEB)

Eibschuetz, M.; Gorodetsky, G.; Shtrikman, S.; Treves, D.

1963-11-15

Curie temperatures of 14 different orthoferrites with the chemical formula RFeO/sub 3/ (R = Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) were measured by differential thermal analysis. Hyperfine interactions of the Fe/ sup 57/ nucleus in the same materials were determined from their Mossbauer spectra. It is found that the quadrupole splitting with the exception of the case of Sm, isomer shift, Curie temperature, and internal field vary regularly with the ionic size of R. (auth)

Gibbs free energy of formation of liquid lanthanide-bismuth alloys

International Nuclear Information System (INIS)

Sheng Jiawei; Yamana, Hajimu; Moriyama, Hirotake

2001-01-01

The linear free energy relationship developed by Sverjensky and Molling provides a way to predict Gibbs free energies of liquid Ln-Bi alloys formation from the known thermodynamic properties of aqueous trivalent lanthanides (Ln 3(5(6+ ). The Ln-Bi alloys are divided into two isostructural families named as the LnBi 2 (Ln=La, Ce, Pr, Nd and Pm) and LnBi (Ln=Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb). The calculated Gibbs free energy values are well agreed with experimental data

Development of solvent extraction process for erbium purification

International Nuclear Information System (INIS)

Singh, D.K.; Anitha, M.; Vijayalakshmi, R.; Chakravartty, J.K.

2016-01-01

Erbium an important heavy rare earth (HRE) finds valuable application in space and nuclear energy technology. High purity erbium oxide is used as coating material for test blanket module of fusion reactor to prevent the tritium permeation. The total concentration of HRE (including Er) in only proven resource of rare earths in Indian monazite mineral is < 0.05%. Its separation from such a low concentration and also from host of other chemically similar elements like Y, Dy, Ho, Yb, Tm etc is quite difficult and challenging. A solvent extraction process employing PC88A and Aliquat336 has been developed for the purification of erbium oxide from two types of HRE fractions having % composition; (i) Y 2 O 3 : 0.18, Tb 4 O 7 : 0.28, Dy 2 CO 2 : 47.07, Er 2 O 3 : 35.03, HO 2 O 3 : 10.11, Yb 2 O 3 : 5.88, Tm 2 O 3 : 1.43 and (ii) Dy 2 O 3 : 6.39, Er 2 O 3 : 49.43, HO 2 O 3 : 10.43, Tm 2 O 3 : 2.7, Y 2 O 3 : 24.08, Yb 2 O 3 : 6.96. PC88A was used to process low Y content concentrate from chloride medium whereas Aliquat336 was found to be suitable in thiocynate medium to treat the concentrate with high Y content. Effects of process variables such as acidity, extractant concentration, total oxide concentration in feed, number of stages, phase ratio, scrubbing agent were investigated for both the systems

Lanthanide phosphonates: Synthesis, thermal stability and magnetic characterization

Energy Technology Data Exchange (ETDEWEB)

Amghouz, Z., E-mail: amghouz.uo@uniovi.es [Departamentos de Quimica Fisica y Analitica y Quimica Organica e Inorganica, Universidad de Oviedo - CINN, 33006 Oviedo (Spain); Garcia, J.R.; Garcia-Granda, S. [Departamentos de Quimica Fisica y Analitica y Quimica Organica e Inorganica, Universidad de Oviedo - CINN, 33006 Oviedo (Spain); Clearfield, A. [Department of Chemistry, Texas A and M University, College Station, TX 77842-3012 (United States); Rodriguez Fernandez, J.; Pedro, I. de [CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander (Spain); Blanco, J.A. [Departamento de Fisica, Universidad de Oviedo, 33007 Oviedo (Spain)

2012-09-25

Highlights: Black-Right-Pointing-Pointer Report of the complete series of lanthanide 1,4-phenylbis(phosphonate). Black-Right-Pointing-Pointer Synthesis under conventional hydrothermal synthesis or microwave-assisted hydrothermal synthesis. Black-Right-Pointing-Pointer Cation size is the key factor for the structural and particles size variations. Black-Right-Pointing-Pointer Thermal behaviour is characterized by unusual very high thermal stability. - Abstract: Series of novel organic-inorganic hybrids materials based on trivalent lanthanides (Ln = Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) and 1,4-phenylbis(phosphonate) obtained under hydrothermal conditions either by oven heat or microwave irradiation. The anhydrous compounds containing La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, and Ho, are isostructural. However, the compounds based on Y, Er, Tm, Yb, and Lu are hydrated and their structures have not yet been solved. The series of compounds are characterized by PXRD, TEM, SEM-EDX and thermal analyses (TG-MS and DSC). TEM study show a variable particles size with a minimum mean-particle size of ca. 30 nm. These compounds exhibit unusual very high thermal stability. The size of particles and the thermal stability are depending on lanthanide(III) cation features. All the investigated materials show paramagnetic behaviour. The magnetic susceptibility data follow a Curie-Weiss laws with paramagnetic effective moments in good agreement with those expected for Ln{sup 3+} free ions.

Effect of separated layer thickness on magnetoresistance and magnetic properties of Co/Dy/Co and Ni/Dy/Ni film systems

Science.gov (United States)

Shabelnyk, T. M.; Shutylieva, O. V.; Vorobiov, S. I.; Pazukha, I. M.; Chornous, A. M.

2018-01-01

Co(5 nm)/Dy(tDy)/Co(20 nm)/S and Ni(5 nm)/Dy(tDy)/Ni(20 nm)/S trilayer films are prepared by electron-beam sputtering to investigate the influence of dysprosium layer thickness (tDy) and thermal annealing on the crystal structure, magnetoresistance (MR) and magnetic properties of thin films. The thickness of Dy layer changed in the range from 1 nm to 20 nm. The samples annealed for 20 min at 700 K. Electron diffraction patterns reveal that the as-deposited and annealed systems Co/Dy/Co and Ni/Dy/Ni had fcc-Co + hcp-Dy and fcc-Ni + hcp-Dy phase state, respectively. It is also shown that at the tDy = 15 nm the transition from amorphous to crystalline structures of Dy layer is observed. An increase in the Dy layer thickness results in changes in the MR and magnetic properties of the trilayer systems. It is shown that MR is most thermally stable against annealing to 700 K at tDy = 15 nm for Co/Dy/Co as well as for Ni/Dy/Ni. For tDy = 15 nm the, value of MR for both system increases by two times compared to those of pure ferromagnetic (FM) samples. The coercivity (Bc), remanent (Mr) and saturation (Ms) magnetization of the in-plain magnetization hysteresis loops are related to the Dy layer thickness too. The coercivity depends on the FM materials type and diffusion processes at the layer boundary. Accordingly, Mr and Ms are reduced with tDy increasing before and after annealing for both trilayer systems.

Buffer layers and articles for electronic devices

Science.gov (United States)

Paranthaman, Mariappan P.; Aytug, Tolga; Christen, David K.; Feenstra, Roeland; Goyal, Amit

2004-07-20

Materials for depositing buffer layers on biaxially textured and untextured metallic and metal oxide substrates for use in the manufacture of superconducting and other electronic articles comprise RMnO.sub.3, R.sub.1-x A.sub.x MnO.sub.3, and combinations thereof; wherein R includes an element selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y, and A includes an element selected from the group consisting of Be, Mg, Ca, Sr, Ba, and Ra.

Magneto, spectral and thermal studies of lanthanum and lanthanide(3) bromide and nitrate complexes of 2,2'bipyridine mono N-oxide

International Nuclear Information System (INIS)

Agarwal, R.K.

1988-01-01

Lanthanide(3) bromide and nitrate complexes of 2,2'-bipyridine mono N-oxide (BipyNO) having the composition Ln(BipyNO) 3 Br 3 and Ln(BipyNO) 2 (NO 3 ) 3 (Ln=La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho and Yb) have been prepared and characterized by means of conductance, molecular weight, magnetic and spectral studies. The ligand acts as a bidentate O,N-chelating agent. The coordination number nine or ten for lanthanide ions has been assigned to these complexes. 3 tabs., 25 refs. (author)

Spectrographic determination of lanthanides in high-purity uranium compounds, after chromatographic separation by alumina-hydrofluoric acid

International Nuclear Information System (INIS)

Lordello, A.R.; Abrao, A.

1979-01-01

A method is presented for the determination of fourteen rare earth elements in high-purity uranium compounds by emission spectrography. The rare earths are chromatographically separated from uranium by using alumina-hydrofluoric acid. Lanthanum is used both as collector and internal standard. The technique of excitation involves a total consumption of the sample in a 17 ampere direct current arc. The range of determination is about 0.005 to 0.5 μg/g uranium. The coefficient of variation for Pr, Ho, Dy, Er, Tm, Lu, Gd and Tb amounts to 10%. (Author) [pt

Thiocarbomide coordination compounds of yttrium subgroup rare earth chlorides

International Nuclear Information System (INIS)

Sakharova, Yu.G.; Perov, V.N.; Loginov, V.I.

1978-01-01

Thiocarbamide coordination compounds of chlorides of elements of the yttrium subgroup 4MeCl 3 x5Cs(NH 2 ) 2 x2OH 2 O (where Me stands for Tb, Dy, Ho, Er, Tm, Yb, Lu, Y) were produced for the first time. The compounds obtained are stable in air, have definite melting points, are highly soluble in methyl and ethyl alcohols, and are unstable in water. They recrystallize from ethyl alcohol without changing their chemical composition. The identity of these compounds was confirmed by X-ray analysis

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.

Defective muscle basement membrane and lack of M-laminin in the dystrophic dy/dy mouse

DEFF Research Database (Denmark)

Xu, H; Christmas, P; Wu, X R

1994-01-01

-linked Duchenne and Becker muscular dystrophies. We have examined M-laminin expression in mice with autosomal recessive muscular dystrophy caused by the mutation dy. The heavy chain of M-laminin was undetectable in skeletal muscle, heart muscle, and peripheral nerve by immunofluorescence and immunoblotting......M-laminin is a major member of the laminin family of basement membrane proteins. It is prominently expressed in striated muscle and peripheral nerve. M-laminin is deficient in patients with the autosomal recessive Fukuyama congenital muscular dystrophy but is normal in patients with the sex...... tissue from dy/dy mice, suggesting that M-laminin heavy-chain mRNA may be produced at very low levels or is unstable. Information about the chromosomal localization of the M heavy-chain in human and mouse suggests that a mutation in the M-chain gene causes the muscular dystrophy in dy/dy mice. The dy...

Construction of Polynuclear Lanthanide (Ln = Dy(III), Tb(III), and Nd(III)) Cage Complexes Using Pyridine-Pyrazole-Based Ligands: Versatile Molecular Topologies and SMM Behavior.

Science.gov (United States)

Bala, Sukhen; Sen Bishwas, Mousumi; Pramanik, Bhaskar; Khanra, Sumit; Fromm, Katharina M; Poddar, Pankaj; Mondal, Raju

2015-09-08

Employment of two different pyridyl-pyrazolyl-based ligands afforded three octanuclear lanthanide(III) (Ln = Dy, Tb) cage compounds and one hexanuclear neodymium(III) coordination cage, exhibiting versatile molecular architectures including a butterfly core. Relatively less common semirigid pyridyl-pyrazolyl-based asymmetric ligand systems show an interesting trend of forming polynuclear lanthanide cage complexes with different coordination environments around the metal centers. It is noteworthy here that construction of lanthanide complex itself is a challenging task in a ligand system as soft N-donor rich as pyridyl-pyrazol. We report herein some lanthanide complexes using ligand containing only one or two O-donors compare to five N-coordinating sites. The resultant multinuclear lanthanide complexes show interesting magnetic and spectroscopic features originating from different spatial arrangements of the metal ions. Alternating current (ac) susceptibility measurements of the two dysprosium complexes display frequency- and temperature-dependent out-of-phase signals in zero and 0.5 T direct current field, a typical characteristic feature of single-molecule magnet (SMM) behavior, indicating different energy reversal barriers due to different molecular topologies. Another aspect of this work is the occurrence of the not-so-common SMM behavior of the terbium complex, further confirmed by ac susceptibility measurement.

Rotational and translational distortions of the crystal structure of the Sr{sub 2}HrRuO{sub 6} (Hr = Ho, Dy, Gd, Eu) complex perovskites

Energy Technology Data Exchange (ETDEWEB)

Triana, C.A., E-mail: ctrianae@unal.edu.co [Grupo de Física de Nuevos Materiales, Departamento de Física, Universidad Nacional de Colombia, A.A. 5997, Bogotá D.C. (Colombia); Landínez Téllez, D.A. [Grupo de Física de Nuevos Materiales, Departamento de Física, Universidad Nacional de Colombia, A.A. 5997, Bogotá D.C. (Colombia); Roa-Rojas, J., E-mail: jroar@unal.edu.co [Grupo de Física de Nuevos Materiales, Departamento de Física, Universidad Nacional de Colombia, A.A. 5997, Bogotá D.C. (Colombia)

2013-05-15

Sr{sub 2}HrRuO{sub 6} (Hr = Ho, Dy, Gd, Eu) complex perovskites were synthesized through the high-temperature solid-state reaction method, and their crystal structures were analyzed in detail as a function of the Hr-cation ionic radius. Results of powder XRD pattern measurement and Rietveld analysis of the experimental profiles show that the Sr{sub 2}HrRuO{sub 6} compounds crystallize in a monoclinic distorted perovskite-like structure, P2{sub 1}/n (#14) space group, where the unit cell parameters are related to the primitive unit cell a{sub p} by a≈√(2)a{sub p}, b≈√(2)a{sub p} and c ≈ 2a{sub p}. The structures show an alternate distribution of the Ru{sup 5+} (2d: 0.5, 0, 0) and Hr{sup 3+} (2c: 0, 0.5, 0) making up RuO{sub 6} and HrO{sub 6} octahedra alternatively arranged in two interleaving fcc sublattices, where the O(1), O(2), and O(3) ions are localized at the corner of the octahedral, while the Sr{sup 2+} is located at the A-site, occupying the cavities built by the corner-sharing octahedra with Wyckoff position 4e. Due to the existence of mismatched ionic sizes between the ionic radii of the Sr{sub 2}HrRuO{sub 6} compounds, the HrO{sub 6} and RuO{sub 6} octahedra are constrained to tilting around the [111]{sub c}, [001]{sub c}, and [110]{sub c} cubic directions so as to optimize the Sr–O inter-atomic bond lengths, tending to rotate the structure in order to fix the Ru{sup 5+} and Hr{sup 3+} ions on the M′ and M″ sites of the complex perovskites. The cell parameters a, b, and c, the inter-atomic bond angles, the inter-atomic bond lengths, and the tilting angles increase as the Hr-cation ionic radius increases. The mismatch that exists in the Sr{sub 2}HrRuO{sub 6} ionic radius produces a large distortion from the ideal cubic symmetry. The pure perovskite-like phase of Sr{sub 2}HrRuO{sub 6} is thermodynamically and kinetically stable at high temperatures above 1420 K, where it is entirely governed by the average size of the Hr{sup 3+} and Ru

Investigations of the magnetic properties in the pyrochlore Ho{sub 2}Ti{sub 2}O{sub 7}

Energy Technology Data Exchange (ETDEWEB)

Schoenemann, Rico; Herrmannsdoerfer, Thomas; Green, Elizabeth Lauren; Wang, Zhaosheng; Wosnitza, Joachim [Dresden High Magnetic Field Laboratory, Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Skrotzki, Richard [Dresden High Magnetic Field Laboratory, Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Department of Chemistry and Food Chemistry, TU Dresden, Dresden (Germany); Kaneko, Hiroshi; Suzuki, Haruhiko [Faculty of Mathematics and Physics, Kanazawa University, Kanazawa (Japan)

2013-07-01

Pyrochlore compounds such as R{sub 2}Ti{sub 2}O{sub 7} (where R is Ho or Dy) have an highly degenerate ground state where the R{sup 3+} moments obey the ''ice rules''. This provides access to study extraordinary physical phenomena, like the formation of magnetic monopoles. Recent publications evidence monopoles which can be probed using high frequency (adiabatic) susceptibility measurements. We performed ac susceptibility measurements on a single-crystal Ho{sub 2}Ti{sub 2}O{sub 7} sample at low temperatures down to 30 mK and magnetic fields up to 14 T. Based on isothermal frequency sweeps we were able to determine spin relaxation rates. Both the real and imaginary parts of the temperature-dependent magnetic susceptibility measurements show the spins freezing below 1 K and provide insight into the magnetic-monopole density.

Sensitivity, completeness and agreement of the tuberculosis electronic system in Ho Chi Minh City, Viet Nam.

Science.gov (United States)

Thai, L H; Nhat, L M; Shah, N; Lyss, S; Ackers, M

2017-12-21

Setting: Since 2011, tuberculosis (TB) clinics in Ho Chi Minh City (HCMC), Viet Nam, have been entering data from a paper-based TB treatment register into an electronic database known as VITIMES (Viet Nam TB Information Management Electronic System), which is currently used in parallel with the paper system. Objective: To evaluate the sensitivity, completeness and agreement of data in VITIMES with that of paper-based registers among TB patients co-infected with the human immunodeficiency virus (HIV) being treated for TB in HCMC. Design: This was a retrospective data review of all TB-HIV patients receiving anti-tuberculosis treatment in each of the 24 district TB clinics in HCMC in 2013. Data were abstracted from the paper-based TB treatment registers at district level and extracted electronically at the provincial level. Records were matched based on name, age and address. The sensitivity, completeness and agreement of the electronic data were compared with data from the paper system. Results: The findings showed that the electronic system had high sensitivity (99.2%), high completeness (87-99%) and high agreement (κ 0.78-0.97) for all variables. Conclusion: The results of this study suggest that data are being correctly entered into VITIMES and that patient data can be directly entered into VITIMES instead of having a parallel, paper-based system.

Antiferromagnetic coupling between rare earth ions and semiquinones in a series of 1:1 complexes.

Science.gov (United States)

Caneschi, Andrea; Dei, Andrea; Gatteschi, Dante; Poussereau, Sandrine; Sorace, Lorenzo

2004-04-07

We use the strategy of diamagnetic substitution for obtaining information on the crystal field effects in paramagnetic rare earth ions using the homologous series of compounds with the diamagnetic tropolonato ligand, Ln(Trp)(HBPz(3))(2), and the paramagnetic semiquinone ligand, Ln(DTBSQ)(HBPz(3))(2), (DTBSQ = 3,5-di-tert-butylsemiquinonato, Trp = tropolonate, HBPz(3)= hydrotrispyrazolylborate) for Ln = Sm(iii), Eu(iii), Gd(iii), Tb(iii), Dy(iii), Ho(iii), Er(iii) or Yb(iii). The X-ray crystal structure of a new form of tropolonate derivative is presented, which shows, as expected, a marked similarity with the structure of the semiquinonate derivative. The Ln(Trp)(HBPz(3))(2) derivatives were then used as a reference for the qualitative determination of crystal field effects in the exchange coupled semiquinone derivatives. Through magnetisation and susceptibility measurements this empirical diamagnetic substitution method evidenced for Er(iii), Tb(iii), Dy(iii) and Yb(iii) derivatives a dominating antiferromagnetic coupling. The increased antiferromagnetic contribution compared to other radical-rare earth metal complexes formed by nitronyl nitroxide ligands may be related to the increased donor strength of the semiquinone ligand.

Addition compounds between same phosphinoxides and hexafluorophosphates of rare earths (III)

International Nuclear Information System (INIS)

Silva, A.M. da; Melo, S.M.; Souza, E.F. de; Almeida, M.A. de

1984-01-01

Coordination compounds were prepared from salts of lanthanide hexafluorophosphates and three different phosphine oxides: methyldiphenylphosphine oxide (MDPPO), diphenylcyclohexylphosphine oxide (DPcHPO) and phosphoric acid trimethylester (TMxPO). The analytical results indicated the following general formulae : Ln(PF 6 ) 3 .5DPChPO where Ln = La, Eu, Gd, Tb and Dy; Ln(PF 6 ) 3 6MDPPO, where Ln = La, Ce, Nd, Eu, Gd, and Tm; Ln(PF 6 ) 3 .7TMxPO, where Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb. The vibrational studies in the infrared region showed that all the phosphine oxides coordination are through the oxygen of the phosphoryl group and confirmed the non-coordination character of the PF - 6 ion. Fluorescence spectra in the visible region for the Eu (III) compounds, at the liquid nitrogen temperature indicated the microsymmetry C sub(3v) as the most probable for the Eu (III) in the compounds Eu (PF 6 ) 3 .5DPChPO and Eu (PF 6 ) 3 .7TMxPO. The symmetry site of the Eu (PF 6 ) 3 .6MDPPO compound is octahedral with tetragonal distortion. (Author) [pt

New tetragonal derivatives of cubic NaZn13-type structure: RNi6Si6 compounds, crystal structure and magnetic ordering (R=Y, La, Ce, Sm, Gd–Yb)

International Nuclear Information System (INIS)

Pani, M.; Manfrinetti, P.; Provino, A.; Yuan, Fang; Mozharivskyj, Y.; Morozkin, A.V.; Knotko, A.V.; Garshev, A.V.; Yapaskurt, V.O.; Isnard, O.

2014-01-01

Novel RNi 6 Si 6 compounds adopt the new CeNi 6 Si 6 -type structure for R=La–Ce (tP52, space group P4/nbm N 125-1) and new YNi 6 Si 6 -type structure for R=Y, Sm, Gd–Yb (tP52, space group P4 ¯ b2N 117) that are tetragonal derivative of NaZn 13 -type structure, like LaCo 9 Si 4 -type. The CeNi 6 Si 6 , GdNi 6 Si 6 , TbNi 6 Si 6 , DyNi 6 Si 6 and HoNi 6 Si 6 compounds are Curie–Weiss paramagnets down to ∼30 K, and do not order magnetically down to 5 K. However, the inverse paramagnetic susceptibility of LaNi 6 Si 6 does not follow Curie–Weiss law. The DyNi 6 Si 6 shows ferromagnetic-like saturation behaviour at 5 K in applied fields of 50 kOe, giving rise to a magnetic moment value of 6.5 μ B /f.u. in 50 kOe. The powder neutron diffraction study in zero applied filed indicates square modulated the c-collinear antiferromagnetic ordering of TbNi 6 Si 6 with K=[±1/4, ±1/4, 0] wave vector below ∼10 K. - Graphical abstract: Novel (La, Ce)Ni 6 Si 6 compounds adopt the new CeNi 6 Si 6 -type structure and (Y, Sm, Gd–Yb) adopt the new YNi 6 Si 6 -type structure that are tetragonal derivative of NaZn 13 -type structure, like LaCo 9 Si 4 -type. The CeNi 6 Si 6 , GdNi 6 Si 6 , TbNi 6 Si 6 , DyNi 6 Si 6 and HoNi 6 Si 6 compounds are Curie–Weiss paramagnets down to ∼30 K, and do not order magnetically down to 4.2 K. The powder neutron diffraction study in zero applied filed indicates square modulated the c-collinear antiferromagnetic ordering of TbNi 6 Si 6 with K=[±1/4, ±1/4, 0] wave vector below ∼10 K. Display Omitted - Highlights: • The new (La, Ce)Ni 6 Si 6 compounds adopt the new CeNi 6 Si 6 -type structure. • The new (Y, Sm, Gd–Yb)Ni 6 Si 6 compounds adopt the new YNi 6 Si 6 -type structure. • TbNi 6 Si 6 has square modulated c-collinear antiferromagnetic ordering below ∼10 K

Influence of Dy in solid solution on the degradation behavior of binary Mg-Dy alloys in cell culture medium.

Science.gov (United States)

Yang, Lei; Ma, Liangong; Huang, Yuanding; Feyerabend, Frank; Blawert, Carsten; Höche, Daniel; Willumeit-Römer, Regine; Zhang, Erlin; Kainer, Karl Ulrich; Hort, Norbert

2017-06-01

Rare earth element Dy is one of the promising alloying elements for magnesium alloy as biodegradable implants. To understand the effect of Dy in solid solution on the degradation of Mg-Dy alloys in simulated physiological conditions, the present work studied the microstructure and degradation behavior of Mg-Dy alloys in cell culture medium. It is found the corrosion resistance enhances with the increase of Dy content in solid solution in Mg. This can be attributed to the formation of a relatively more corrosion resistant Dy-enriched film which decreases the anodic dissolution of Mg. Copyright © 2017 Elsevier B.V. All rights reserved.

Preparation, thermodynamic property and antimicrobial activity of some rare-earth (III) complexes with 3-bromo-5-iodobenzoic acid and 1,10-phenanthroline

Energy Technology Data Exchange (ETDEWEB)

Liu, Jing-Yu [Testing and Analysis Center, Hebei Normal University, Shijiazhuang 050024 (China); College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang 050024 (China); Ren, Ning [Department of Chemistry, Handan College, Handan 056005 (China); Zhang, Jian-Jun, E-mail: jjzhang6@126.com [Testing and Analysis Center, Hebei Normal University, Shijiazhuang 050024 (China); College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang 050024 (China); Zhang, Cun-Ying [No.1 High School of Shijiazhuang, Shijiazhuang 050011 (China)

2013-10-20

Graphical abstract: Four new rare-earth complexes of general formula [Ln(3-Br-5-IBA){sub 3}phen]{sub 2} [Ln = Er (1), Tb (2), Dy (3) and Ho (4); 3-Br-5-IBA = 3-bromo-5-iodobenzoate; phen = 1,10-phenanthroline] were synthesized and characterized by elemental analysis, IR, UV and TG/DSC-FTIR technology. Heat capacities of the four complexes were measured by differential scanning calorimetry (DSC). The antimicrobial activity against Escherichia coli, Staphylococcus aureus and Candida albicans were tested using disc diffusion method. - Highlights: • Four new complexes [Ln(3-Br-5-IBA){sub 3}phen]{sub 2} were synthesized and characterized. • The non-isothermal kinetics of the first stage for the complexes was studied. • The heat capacities of the complexes were measured by differential scanning calorimeter. • The antimicrobial activities for these complexes were tested. • The fluorescence properties of the complexes 2 and 3 were studied. - Abstract: Four new rare-earth complexes of general formula [Ln(3-Br-5-IBA){sub 3}phen]{sub 2} (Ln(III) = Er (1), Tb (2), Dy (3) and Ho (4); 3-Br-5-IBA = 3-bromo-5-iodobenzoate; phen = 1,10-phenanthroline) were synthesized by solution-precipitation method, and investigated using elemental analysis, infrared spectra, ultraviolet spectra and TG/DSC-FTIR technology. The non-isothermal kinetics of the first stage for the complexes was studied by using non-linear integral isoconversional method and double equal-double steps method. The heat capacities of the complexes were measured between 263.15 and 485.55 K by means of differential scanning calorimeter, and the values of the experimental heat capacities were fitted to a polynomial equation with the least-squares method. And the thermodynamic functions [H{sub T} − H{sub 298.15}], [S{sub T} − S{sub 298.15}] and [G{sub T} − G{sub 298.15}] were also derived based on the fitted polynomials and thermodynamic relationships with temperature interval of 10 K. Moreover, the

Magnetic properties of Dy/Zr multilayers

International Nuclear Information System (INIS)

Luche, M.C.; Boyer, P.

1992-01-01

[Dy(xA)/Zr(30A)] n superlattices (x ≤ 30), were evaporated under ultra-high vacuum on Si(100) substrates. Magnetization measurements indicate that the antiferromagnetic transition occurring at 178K in bulk Dy is suppressed in the multilayers. This phenomenon is attributed to magnetoelastic effects induced by strains at Zr/Dy interfaces. A perpendicular magnetic anisotropy takes place for x ≤ 15. However, the magnetic anisotropy is found to depend markedly on the technique used for Dy deposition. (author). 11 refs., 4 figs

Studies of yrast and continuum states in A=140-160 nuclei. Progress report, January 1, 1980-December 31, 1980

International Nuclear Information System (INIS)

Daly, P.J.

1981-01-01

The structure of nuclei in the A approx. 150 region was investigated by in-beam γ-ray spectroscopy using heavy-ion beams, mostly from the Argonne Tandem-Linac. Results for the nuclei 148 Dy, 149 Dy, 153 Dy, 154 Dy, 149 Ho, and 150 Ho are summarized. The feeding of yrast states in these nuclei and the link between the highest known yrast states and the continuum region were also studied. 6 figures

Gamma ray induced decomposition of lanthanide nitrates

International Nuclear Information System (INIS)

Joshi, N.G.; Garg, A.N.

1992-01-01

Gamma ray induced decomposition of the lanthanide nitrates, Ln(NO 3 ) 3 .xH 2 O where Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm and Yb has been studied at different absorbed doses up to 600 kGy. G(NO 2 - ) values depend on the absorbed dose and the nature of the outer cation. It has been observed that those lanthanides which exhibit variable valency (Ce and Eu) show lower G-values. An attempt has been made to correlate thermal and radiolytic decomposition processes. (author). 20 refs., 3 figs., 1 tab

Research of magnetism by neutron diffraction About 30 years with KUR-TAS

International Nuclear Information System (INIS)

Kawano, Shinji

2005-01-01

The author started his researches in KUR in 1969. This paper includes development of devices and his works. Development of the high pressure cell, the high magnetic field system, the high pressure and magnetic field and low temperature system and software, improvement and maintenance of these systems are reported. Some examples of works such as the magnetic structure and the magnetic phase diagram of Er-Y-La alloy, the helifan structure of Ho, the magnetic structure of Er under high pressure, the magnon measurement of Tb under high pressure, and the magnetic structure of DyNiSn are stated. (S.Y.)

Treatment: Latent TB Infection (LTBI) and TB Disease

Science.gov (United States)

... Adverse Events TB Treatment of Persons Living with HIV TB Treatment and Pregnancy TB Treatment for Children Drug-Resistant TB Research TB Epidemiologic Studies Consortium Research Projects Publications TB Trials Consortium Study ...

Clinical trial of {sup 166}Ho-CHICO in the treatment of rheumatoid knee synovitis

Energy Technology Data Exchange (ETDEWEB)

Kim, S. Y.; Yoo, D. H.; Bae, S. C.; Lee, I. H.; Jung, S. S.; Jun, J. B.; Kim, T. H.; Kim, S. S. [Hanyang Univ., Seoul (Korea)

2000-03-01

The untreated, chronic synovial inflammation leads to pannus formation and eventual destruction of the articular cartilage. In cases where medical therapy was unsuccessful, surgical of radiation synovectomy over surgical synovectomy are (1) greater destruction of diseased synovium, (2) reduced Potential for blood clots and infection, (3) no requirement for anesthesia, and (4) less costly and less time consuming. Recently KAERI developed Dy-165 HMA, which was characterized by the absence of iron and a higher concentration of dysprosium. And then more recently KAERI also developed {sup 16H}o-CHICO, which was characterized by relatively longer half-life (26.8 hr), more biological due to organic nature of chitosan, more even spatial distribution due to colloidal solution, and more absorbable to synovium than Dy-165 HMA. These long-term follow-up results indicate that the {sup 166}Ho-CHICO is an effective and safe agent for radiation synovectomy for knee synovitis in patients with rheumatoid arthritis as well as the other chronic arthritides. But further large scaled and controlled study are required. 16 refs. (Author)

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.)

The low-energy β(-) and electron emitter (161)Tb as an alternative to (177)Lu for targeted radionuclide therapy.

Science.gov (United States)

Lehenberger, Silvia; Barkhausen, Christoph; Cohrs, Susan; Fischer, Eliane; Grünberg, Jürgen; Hohn, Alexander; Köster, Ulli; Schibli, Roger; Türler, Andreas; Zhernosekov, Konstantin

2011-08-01

The low-energy β(-) emitter (161)Tb is very similar to (177)Lu with respect to half-life, beta energy and chemical properties. However, (161)Tb also emits a significant amount of conversion and Auger electrons. Greater therapeutic effect can therefore be expected in comparison to (177)Lu. It also emits low-energy photons that are useful for gamma camera imaging. The (160)Gd(n,γ)(161)Gd→(161)Tb production route was used to produce (161)Tb by neutron irradiation of massive (160)Gd targets (up to 40 mg) in nuclear reactors. A semiautomated procedure based on cation exchange chromatography was developed and applied to isolate no carrier added (n.c.a.) (161)Tb from the bulk of the (160)Gd target and from its stable decay product (161)Dy. (161)Tb was used for radiolabeling DOTA-Tyr3-octreotate; the radiolabeling profile was compared to the commercially available n.c.a. (177)Lu. A (161)Tb Derenzo phantom was imaged using a small-animal single-photon emission computed tomography camera. Up to 15 GBq of (161)Tb was produced by long-term irradiation of Gd targets. Using a cation exchange resin, we obtained 80%-90% of the available (161)Tb with high specific activity, radionuclide and chemical purity and in quantities sufficient for therapeutic applications. The (161)Tb obtained was of the quality required to prepare (161)Tb-DOTA-Tyr3-octreotate. We were able to produce (161)Tb in n.c.a. form by irradiating highly enriched (160)Gd targets; it can be obtained in the quantity and quality required for the preparation of (161)Tb-labeled therapeutic agents. Copyright © 2011 Elsevier Inc. All rights reserved.

Magnetooptic effects and Auger electron spectroscopy of two-layer NiFe-Dy and Fe-Dy films with nonuniform layers

International Nuclear Information System (INIS)

Ehdel'man, I.S.; Markov, V.V.; Khudyakov, A.E.; Ivantsov, R.D.; Bondarenko, G.V.; Ovchinnikov, S.G.; Kesler, V.G.; Parshin, A.S.; Ronzhin, I.P.

2001-01-01

Magneto-optical effects (magnetic circular dichroism and meridional Kerr effect) and element distribution with layer thickness in two-layer NiFe-Dy and Fe-Dy films, prepared by thermal sputtering of component in ultrahigh vacuum, are investigated. It is shown, that Dy in a two-layer film in the temperature range of 80-300 K makes constant contributions to both effects investigated which are approximately equal to the values of the effects observed in an isolated Dy film only at temperatures below the temperature T c of Dy transition into a ferromagnetic state (T c ∼ 100 K for the films under study). This behaviour of magneto-optical effects is assumed to be due to the influence of a NiFe layer spin system on magnetic state of a Dy layer, this influence is enhanced by the deep penetration of Ni and Fe ions into Dy layer as it follows from the data obtained using Auger electron spectroscopy [ru

Superdeformed bands in /sup 150/Gd and /sup 151/Tb: Evidence for the influence of high-N intruder states at large deformations

Energy Technology Data Exchange (ETDEWEB)

Fallon, P.; Alderson, A.; Bentley, M.A.; Bruce, A.M.; Forsyth, P.D.; Howe, D.; Roberts, J.W.; Sharpey-Schafer, J.F.; Twin, P.J.; Beck, F.A.

1989-02-16

Rotational bands, characteristic of a superdeformed prolate shape (epsilon approx. = 0.6) and extending to above spin 60 Planck constant, have been observed in both /sup 150/Gd and /sup 151/Tb. The magnitudes of the moments of inertia I/sup (2)/ were found to vary with frequency and the variation greatly exceeded that seen in /sup 148,149/Gd and /sup 151,152/Dy. The differences in the I/sup (2)/'s are attributed to the occupation of particular high-N orbitals. Moreover, contrary to the previous examples the bands in both /sup 150/Gd and /sup 151/Tb de-excited at a much higher rotational frequency of Planck constant..omega.. approx. = 0.4 MeV and this may indicate that the pair gap extends to higher frequencies in /sup 150/Gd and /sup 151/Tb.

Thermoluminescence properties of Al2O3:Tb nanoparticles irradiated by gamma rays and 85 MeV C6+ ion beam

International Nuclear Information System (INIS)

Salah, Numan; Alharbi, Najlaa D.; Habib, Sami S.; Lochab, S.P.

2015-01-01

Carbon ions beam is recently recognized as an ideal cancer treatment modality, because of its excellent local tumor control. These ions have a high relative biological effectiveness resulting from high linear energy transfer (LET) and their sharp Bragg peak. However, the dose of those energetic ions needs to be measured with great precision using a proper dosimeter. Aluminum Oxide (Al 2 O 3 ) is a highly luminescent phosphor widely used for radiation dosimetry using thermoluminesence (TL) technique. In this work nanoparticles of this material activated by different elements like Eu, Tb, Dy, Cu and Ag were evaluated for their TL response to gamma rays irradiation. Tb doped sample is found to be the most sensitive sample, which could be selected for exposure to 85 MeV C 6+ ion beam in the fluence range 10 9 –10 13 ions/cm 2 . The obtained result shows that C ion beam irradiated sample has a simple glow curve structure with a prominent glow peak at around 230 °C. This glow curve has a dosimetric peak better than those induced by gamma rays. This glow peak exhibits a linear response in the range 10 9 –10 11 ions/cm 2 , corresponding to the equivalent absorbed doses 0.285–28.5 kGy. The absorbed doses, penetration depths and main energy loss were calculated using TRIM code based on the Monte Carlo simulation. The wide linear response of Al 2 O 3 :Tb nanoparticles along with the low fading makes this low cost nanomaterial a good candidate for C ion beam dosimetry. - Highlights: • Nanoparticles of Al 2 O 3 doped with Eu, Tb, Dy, Cu and Ag were synthesised. • They were evaluated for their TL response to gamma rays and C ion beam irradiation. • Tb doped sample is the most sensitive sample to gamma rays. • Al 2 O 3 :Tb was exposed to 85 MeV C 6+ ion beam in the fluence range 10 9 -10 13 ions/cm 2 . • The glow peak induced by C ions has a linear response in the range 10 9 -10 11 ions/cm 2

Estimation of human absorbed dose for (166)Ho-PAM: comparison with (166)Ho-DOTMP and (166)Ho-TTHMP.

Science.gov (United States)

Vaez-Tehrani, Mahdokht; Zolghadri, Samaneh; Yousefnia, Hassan; Afarideh, Hossein

2016-10-01

In this study, the human absorbed dose of holmium-166 ((166)Ho)-pamidronate (PAM) as a potential agent for the management of multiple myeloma was estimated. (166)Ho-PAM complex was prepared at optimized conditions and injected into the rats. The equivalent and effective absorbed doses to human organs after injection of the complex were estimated by radiation-absorbed dose assessment resource and methods proposed by Sparks et al based on rat data. The red marrow to other organ absorbed dose ratios were compared with these data for (166)Ho-DOTMP, as the only clinically used (166)Ho bone marrow ablative agent, and (166)Ho-TTHMP. The highest absorbed dose amounts are observed in the bone surface and bone marrow with 1.11 and 0.903 mGy MBq(-1), respectively. Most other organs would receive approximately insignificant absorbed dose. While (166)Ho-PAM demonstrated a higher red marrow to total body absorbed dose ratio than (166)Ho-1,4,7,10-tetraazacyclo dodecane-1,4,7,10 tetra ethylene phosphonic acid (DOTMP) and (166)Ho-triethylene tetramine hexa (methylene phosphonic acid) (TTHMP), the red marrow to most organ absorbed dose ratios for (166)Ho-TTHMP and (166)Ho-PAM are much higher than the ratios for (166)Ho-DOTMP. The result showed that (166)Ho-PAM has significant characteristics than (166)Ho-DOTMP and therefore, this complex can be considered as a good agent for bone marrow ablative therapy. In this work, two separate points have been investigated: (1) human absorbed dose of (166)Ho-PAM, as a potential bone marrow ablative agent, has been estimated; and (2) the complex has been compared with (166)Ho-DOTMP, as the only clinically used bone marrow ablative radiopharmaceutical, showing significant characteristics.

Effects of 3d-4f magnetic exchange interactions on the dynamics of the magnetization of Dy(III)-M(II)-Dy(III) trinuclear clusters.

Science.gov (United States)

Pointillart, Fabrice; Bernot, Kevin; Sessoli, Roberta; Gatteschi, Dante

2007-01-01

[{Dy(hfac)(3)}(2){Fe(bpca)(2)}] x CHCl(3) ([Dy(2)Fe]) and [{Dy(hfac)(3)}(2){Ni(bpca)(2)}]CHCl(3) ([Dy(2)Ni]) (in which hfac(-)=1,1,1,5,5,5-hexafluoroacetylacetonate and bpca(-)=bis(2-pyridylcarbonyl)amine anion) were synthesized and characterized. Single-crystal X-ray diffraction shows that [Dy(2)Fe] and [Dy(2)Ni] are linear trinuclear complexes. Static magnetic susceptibility measurements reveal a weak ferromagnetic exchange interaction between Ni(II) and Dy(III) ions in [Dy(2)Ni], whereas the use of the diamagnetic Fe(II) ion leads to the absence of magnetic exchange interaction in [Dy(2)Fe]. Dynamic susceptibility measurements show a thermally activated behavior with the energy barrier of 9.7 and 4.9 K for the [Dy(2)Fe] and [Dy(2)Ni] complexes, respectively. A surprising negative effect of the ferromagnetic exchange interaction has been found and has been attributed to the structural conformation of these trinuclear complexes.

Návrh výroby chytrého stojanu s využitím moderních metod a technologií

OpenAIRE

Buchta, Juraj

2017-01-01

Cieľom bakalárskej práce je návrh, konštrukcia a výroba chytrého stojanu pre laptop Macbook Pro s využitím modernej aditívnej technológie Rapid Prototyping. Návrh je vytvorený pomocou parametrického CAD programu SolidWorks. Model stojana je vytlačený na 3D tlačiarni Fortus, ktorá pracuje na princípe aditívnej metódy Fused Deposition Modeling. Práca je ukončená ekonomickým zhodnotením celkových nákladov na výrobu a cenovým zrovnaním stojanov dostupných na trhu. The aim of bachelor´s thesis ...

Isothermal sections at 500 deg C of the Dy-V-Al and Dy-Cr-Al systems in the aluminium rich regions

International Nuclear Information System (INIS)

Rykhal', R.M.; Zarechnyuk, O.S.; Mats'kiv, O.P.

1979-01-01

X-ray diffraction and microscopic analyses have been used to investigate the ternary system dysprosium-vanadium-aluminium in the aluminium rich region. In the system Dy-V-Al two ternary compounds have been found: DyV 2 Al 20 (cubic structure, CeCr 2 Al 20 type, a=14.54 A and approximately DyVAl 8 (hexagonal crystal system, structure unknown, a=10.86, c=17.71 A, c/a=1.631). In the system dysprosium-chromium-aluminium three ternary compounds have been found: DyCr 2 Al 20 (cubic structure, CeCr 2 Al 20 type, a=14.39), approximately equal to DyCrAl 8 ) hexagonal crystal system, structure type unkown a=10.75, c=17.60 A, c/a=1.637) and DyCr 4 Al 8 (tetragonal structure, CeMn 4 Al 8 type, a=8.87, c=5.04 A, c/a=0.568). Isothermal sections of the systems Dy-V-Al and Dy-Cr-Al have been plotted at 500 deg C

Extension of the energy range of the experimental activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium up to 65MeV.

Science.gov (United States)

Tárkányi, F; Ditrói, F; Takács, S; Hermanne, A; Ignatyuk, A V

2015-04-01

Activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium were extended up to 65MeV by using stacked foil irradiation and gamma spectrometry experimental methods. Experimental cross-sections data for the formation of the radionuclides (159)Dy, (157)Dy, (155)Dy, (161)Tb, (160)Tb, (156)Tb, (155)Tb, (154m2)Tb, (154m1)Tb, (154g)Tb, (153)Tb, (152)Tb and (151)Tb are reported in the 36-65MeV energy range, and compared with an old dataset from 1964. The experimental data were also compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS nuclear reaction model code as listed in the latest on-line libraries TENDL 2013. Copyright © 2015. Published by Elsevier Ltd.

Studies of the energy transfer processes from Er{sup 3+} and Ho{sup 3+} to Nd{sup 3+}, Tb{sup 3+} or Eu{sup 3+} in LiYF{sub 4} crystal and ZBLAN glass for the laser media optimization operating near 3{mu}m region; Estudos dos processos de transferencia de energia dos ions de Er{sup 3+} e Ho{sup 3+} para os ions de Nd{sup 3+}, Tb{sup 3+} e Eu{sup 3+} no cristal de LiYF{sub 4} e no vidro ZBLAN para a otimizacao de meios laser ativos que operam na regiao de 3{mu}m

Energy Technology Data Exchange (ETDEWEB)

Jagosich, Fabio Henrique

2006-07-01

The energy transfer processes (ET) from the {sup 4}I{sub 13/2}; {sup 4}I{sub 11/2} levels of Er{sup 3+} and {sup 5}I{sub 6} levels of Ho{sup 3+} ions in LiYF{sub 4} (YLF) crystal and ZBLAN glass to Nd{sup 3+}, Tb{sup 3+} or Eu{sup 3+} deactivators ions were studied. The micro parameters of these energy transfer processes were determined using the overlap integral method, and showed that Eu{sup 3+} ion is the best deactivator of the first excited state of the Ho{sup 3+} in YLF, and Nd{sup 3+} is the best deactivator of the Er{sup 3+} in YLF and ZBLAN materials. The 1.5 and 2.7{mu}m emissions of Er{sup 3+} and 2.1 and 2.9{mu}m fluorescence of Ho{sup 3+} were measured using short laser pulses excitations from a tunable OPO pumped 2w-Nd:YAG laser system. We proposed a criterion for discriminating the energy transfer processes assisted by excitation migration (diffusion or hopping) among donors. It was observed that diffusion model describes the ET process from the second excited state of the donor (Er{sup 3+} or Ho{sup 3+}) independently of the C{sub D-D}/C{sub D-A} ratio, while the hopping model can describe the ET process involving the first excited state of donor. We proposed a modification of the hopping model in order to describe the experimental results for systems having C{sub D-D}/C{sub D-A} {>=} 10. Using the ET parameters, we determined that the best systems for laser action at 3{mu}m are the Ho:Eu:YLF, Ho:Nd:YLF and Er:Nd:YLF systems. On the other hand, we found that Er{sup 3+} doped (1.5 mol%) ZBLAN glasses, single and co-doped with Nd{sup 3+}, Tb{sup 3+} or Eu{sup 3+}, do not show potential for laser action at 2.8{mu}m. The up-conversion processes were studied in Er:YLF systems as a function of the Er{sup 3+} concentration, and the excited state absorption (ESA) and up conversion by energy transfer (ETU) processes were discriminated using a time resolved fluorescence decays. It was observed that 980 nm is the most convenient wavelength for pumping the Er

Phase equilibria in Dy-Cu-Al system at 500 deg C

International Nuclear Information System (INIS)

Kuz'ma, Yu.B.; Milyan, V.V.

1989-01-01

Using the methods of X-ray diffraction analysis a diagram of phase equilibria in Dy-Cu-Al system at 500 deg C is plotted. Boundaries of solid solutions on the basis of DyCu 2 , DyCu and DyAl 2 compounds are determined and homogeneity regions of ternary compounds Dy 2 (Cu, Al) 7 and Dy(CuAl) 5 are ascertained. Compounds DyCuAl 3 , Dy 4 Cu 4 Al 11 and Dy 5 Cu 6 Al 9 have been detected for the first time

Mechanoluminescence of Dy doped strontium aluminate nanophosphors

Energy Technology Data Exchange (ETDEWEB)

Sharma, Ravi, E-mail: rvsharma65@gmail.com [Department of Physics, Govt. Arts and Commerce Girls College, Raipur, C.G. 492001 (India); Bisen, D.P. [School of Studies in Physics and Astrophysics, Pt. Ravishankar Shukla University, Raipur, C.G. 492010 (India); Chandra, B.P. [Department of Postgraduate Studies and Research in Physics and Electronics, Rani Durgavati University, Jabalpur 482001 (India)

2015-12-15

Nanosized strontium aluminate phosphors activated with Dy{sup 3+} were prepared by a combustion method. Nanophosphor was prepared by this method at reaction temperatures as low as 600 °C. Powder X-ray diffraction (XRD), scanning electron microscope analysis was used to characterize the prepared product. The monoclinic phase was observed in the XRD pattern. The particle size of the samples was calculated around 35 nm. The SEM images show irregular shape of the prepared nanophosphor. Two peaks were found in the mechanoluminescence (ML) response curve plotted between time and ML intensity. The H{sub 3}BO{sub 3} added strontium aluminate phosphors activated with Dy show more bright ML peak as compared to the powders of SrAl{sub 2}O{sub 4}:Dy{sup 3+} without H{sub 3}BO{sub 3.} It was found that the PL and ML intensity increases with increasing concentration of Dy, it becomes maximum for 3% of Dy. The photoluminescence emission shows two intense fluorescence transitions peaks at 498 nm and 583 nm, {sup 4}F{sub 9/2}→{sup 6}H{sub 15/2} in the blue and {sup 4}F{sub 9/2}→{sup 6}H{sub 13/2} in the yellow-orange wavelength region. - Highlights: • Combustion synthesis route is used to prepare the SrAl{sub 2}O{sub 4}: Dy {sup 3+} nanophosphors. • The size of the synthesized sample was found to be in the nano-meter range. • The mechanoluminescence of SrAl{sub 2}O{sub 4}:Dy {sup 3+} nanophosphors is studied. • The photoluminescence of SrAl{sub 2}O{sub 4}: Dy {sup 3+} nanophosphors showed blue-shift as compared to bulk. • Effect of H{sub 3}BO{sub 3} on the mechanoluminescence of SrAl{sub 2}O{sub 4}:Dy{sup 3+} was studied.

Hexagonal perovskites with cationic vacancies. 33. Compounds of type Ba/sub 6-x/Sr/sub x/B/sub 2-y//sup 3 +/SE/sub y//sup 3 +/W/sub 3/vacantO/sub 18/

Energy Technology Data Exchange (ETDEWEB)

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

1982-12-01

In the series Ba/sub 6-x/Sr/sub x/Lu/sub 2-y/SE/sub y//sup 3 +/W/sub 3/vacantO/sub 18/ a substitution of Sr/sup 2 +/ for Ba/sup 2 +/ is possible. According to intensity calculations on powder data of BaSr/sub 5/Lu/sub 1.6/Ho/sub 0.4/W/sub 3/vacantO/sub 18/ the compounds crystallize in a rhombohedral 18 L type with the sequence (hhccc)/sub 3/; space group R-3m. The refined, intensity related R' value is 11.5%. The differences in properties (diffuse reflectance spectra, photoluminescence) between the hexagonal modifications Ba/sub 6/B/sub 2-y//sup 3 +/SE/sub y//sup 3 +/W/sub 3/vacantO/sub 18/ (B/sup 3 +/ = Gd, Y, Lu; SE/sup 3 +/ = Sm, Eu, Tb, Dy, Ho, Er, Tm) and the corresponding cubic HT modifications are discussed.

First-order transitions, symmetry, and the element of-expansion

International Nuclear Information System (INIS)

Mukamel, D.; Krinsky, S.; Bak, P.

1975-01-01

The group theoretical method of Landau and Lifshitz was used to derive effective Hamiltonians for certain paramagnetic to antiferromagnetic transitions having order-parameters with n greater than or equal to 4 components. A renormalization group analysis in 4-epsilon dimensions was performed. The first-order nature of the order-disorder transitions in Cr(n = 12), Eu(n = 12), UO 2 (n = 6), and MnO(n = 8) can be explained by noting that the corresponding Hamiltonians possess no stable fixed points in 4-epsilon dimensions. It is predicted that all fcc type I(anti m perpendicular anti k), type II and type III(anti m perpendicular [100], anti k = [1/2 01]) antiferromagnetic transitions are first-order. The work is intended to serve as a guide in an experimental search for new examples of first-order transitions. A 2m-component Hamiltonian is also considered which possesses a unique, nonisotropic, stable fixed point for each value of 2m greater than or equal to 4. When 2m = 4, the Hamiltonian describes the paramagnetic to antiferromagnetic transitions in TbAu 2 , DyC 2 , Tb, Ho, Dy, and the structural transition in NbO 2 . If these transitions are second-order, it is predicted they all belong to the same universality class. For 2m = 6, the Hamiltonian describes the antiferromagnetic transitions in TbD 2 , Nd, K 2 IrCl 6 , and MnS 2 . These transitions belong to a single universality class

Asteroids Dynamic Site-AstDyS

Science.gov (United States)

Knezevic, Zoran; Milani, Andrea

2012-08-01

The AstDyS online information service (http://hamilton.dm.unipi.it/astdys/) contains data on numbered and multi - opposition asteroids, including orbital elements, their uncertainty, proper elements, ephemerides with uncertainty, and more. AstDyS also provides additional scientific output computed from the raw observational data. This value added currently includes: more accurate orbits computed with advanced dynamical and observational error model s; their uncertainty, as expressed by the covariance matrix formalism; ephemerides computed on request for each observer, with uncertainty; mean and proper orbital elements (for this output, AstDyS is the primary source worldwide); statistical quality control, providing a rigorous observational error model. All this is available with a sophisticated web interface, providing multiple search functions and online computations as well as complete orbital and residual files. There are several ways in which the A stDyS service could be expanded and improved in the next future, like the explicit classification of asteroids into asteroid families, the classification of resonant asteroids, and an updated self - consistent population model (to be used, e.g., for survey simulations). The IAU Division I endorsed the proposal for AstDyS to become an IAU (permanent) service, which would include the IAU supervision of the AstDyS system, keeping under control the quality of the work and the continuous update under conditions of scientific competition.

The Ras antagonist, farnesylthiosalicylic acid (FTS, decreases fibrosis and improves muscle strength in dy/dy mouse model of muscular dystrophy.

Directory of Open Access Journals (Sweden)

Yoram Nevo

Full Text Available The Ras superfamily of guanosine-triphosphate (GTP-binding proteins regulates a diverse spectrum of intracellular processes involved in inflammation and fibrosis. Farnesythiosalicylic acid (FTS is a unique and potent Ras inhibitor which decreased inflammation and fibrosis in experimentally induced liver cirrhosis and ameliorated inflammatory processes in systemic lupus erythematosus, neuritis and nephritis animal models. FTS effect on Ras expression and activity, muscle strength and fibrosis was evaluated in the dy(2J/dy(2J mouse model of merosin deficient congenital muscular dystrophy. The dy(2J/dy(2J mice had significantly increased RAS expression and activity compared with the wild type mice. FTS treatment significantly decreased RAS expression and activity. In addition, phosphorylation of ERK, a Ras downstream protein, was significantly decreased following FTS treatment in the dy(2J/dy(2J mice. Clinically, FTS treated mice showed significant improvement in hind limb muscle strength measured by electronic grip strength meter. Significant reduction of fibrosis was demonstrated in the treated group by quantitative Sirius Red staining and lower muscle collagen content. FTS effect was associated with significantly inhibition of both MMP-2 and MMP-9 activities. We conclude that active RAS inhibition by FTS was associated with attenuated fibrosis and improved muscle strength in the dy(2J/dy(2J mouse model of congenital muscular dystrophy.

Static magnetic susceptibility, crystal field and exchange interactions in rare earth titanate pyrochlores.

Science.gov (United States)

Malkin, B Z; Lummen, T T A; van Loosdrecht, P H M; Dhalenne, G; Zakirov, A R

2010-07-14

The experimental temperature dependence (T = 2-300 K) of single crystal bulk and site susceptibilities of rare earth titanate pyrochlores R(2)Ti(2)O(7) (R = Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb) is analyzed in the framework of crystal field theory and a mean field approximation. Analytical expressions for the site and bulk susceptibilities of the pyrochlore lattice are derived taking into account long range dipole-dipole interactions and anisotropic exchange interactions between the nearest neighbor rare earth ions. The sets of crystal field parameters and anisotropic exchange coupling constants have been determined and their variations along the lanthanide series are discussed.

Nuclear Data Sheets for A=158

Energy Technology Data Exchange (ETDEWEB)

Nica, N. [Cyclotron Institute, Texas A& M University, College Station, TX 77843-3366 (United States); On leave from the National Institute for Physics and Nuclear Engineering “Horia Hulubei”, Bucharest (Romania); Under Subcontract No. 100586 with National Nuclear Data Center, Brookhaven National Laboratory, Upton, NY 11973 (United States)

2017-03-15

The experimental results published before February 2017 from the various reaction and decay studies leading to nuclides {sup 158}Nd, {sup 158}Pm, {sup 158}Sm, {sup 158}Eu, {sup 158}Gd, {sup 158}Tb, {sup 158}Dy, {sup 158}Ho, {sup 158}Er, {sup 158}Tm, {sup 158}Yb, {sup 158}Lu, {sup 158}Hf, {sup 158}Ta, {sup 158}W in the A=158 mass chain have been reviewed. These data are summarized and presented, together with adopted level schemes and properties. Large sections of the mass chain are almost identical to the ones in the previous 2004He05 NDS publication by R.G. Helmer.

Effect of hydrostatic and chemical pressure on the exchange interaction in magnetic borocarbide superconductors

Science.gov (United States)

Michor, H.; El-Hagary, M.; Naber, L.; Bauer, E.; Hilscher, G.

2000-03-01

The investigation of pair-breaking effects in magnetic rare-earth nickel borocarbide superconductors reveals a considerable increase of the magnetic exchange integral Jsf by hydrostatic as well as chemical pressure. In both, Jsf is governed by the R-C distance (or lattice constant a) and is described quantitatively by a simple phenomenological model. Thereby, just two parameters Jsf0=31 meV and ΔJsf/Δa=165 meV/Å explain well the influence of chemical pressure upon the initial depression rates of Tc in solid solutions R'1-xRxNi2B2C with R=Gd, Tb, Dy, Ho and R'=Y and Lu.

Faraday effect in rare-earth ferrite garnets located in strong magnetic fields

International Nuclear Information System (INIS)

Valiev, U.V.; Zvezdin, A.K.; Krinchik, G.S.; Levitin, R.Z.; Mukimov, K.M.; Popov, A.I.

1983-01-01

The Faraday effect is investigated experimentally in single crystal specimens of rare earth iron garnets (REIG) R 3 Fe 5 O 12 (R=Y, Gd, Tb, Dy, Er, Tm, Yb, Eu, Sm and Ho) and also in mixed iron garnets Rsub(x)Ysub(3-x)Fesub(5)Osub(12) (R=Tb, Dy). The m.easurements are carried out in pulsed magnetic fields of intensity up to 200 kOe, in a temperature range from 4.2 to 300 K and at a wavelength of the light lambda=1.15 μm. The field dependence of the Faraday effect observed in the REIG cannot be explained if only the usually considered ''paramagnetic'' contribution to the Faraday effect is taken into account. A theory is developed which, besides the paramagnetic mechanism, takes into account a diamagnetic mechanism and also the mixing of the wave functions of the ground and excited multiplets. The contributions of each of these three mechanisms to the angle of rotation of the plane of polarization by the rare earth sublattice of the iron garnet are estimated theoretically. It is concluded that the mixing mechanism contributes significantly to the field and temperature dependences of the Faraday effect in REIG

Magnetic excitations in Ho2Co17 and Ho2Fe17

International Nuclear Information System (INIS)

Clausen, K.N.

1981-01-01

The low energy part ( 2 Co 17 and Ho 2 Fe 17 have been measured along the three high symmetry directions at a temperature of 4.2 K, using the inelastic neutron scattering technique. The resulting magnon dispersion relations have been interpreted using linear spin wave theory with a Hamiltonian including single ion crystal field anisotropy and isotropic exchange between spatially well localized spins. The R 2 T 17 structure contains two different Ho sites, with the same point symmetry, and from the spin wave results it was concluded that the crystal field anisotropy of the two Ho sites in both Ho 2 Co 17 and Ho 2 Fe 17 were identical. The deduced crystal field parameters for Ho 2 Fe 17 were slightly larger than for Ho 2 Co 17 , and the parameters were of the same order of magnitude as for pure Ho. For Ho 2 Fe 17 the Fe-Fe exchange was found to be anisotropic, and for both compounds the magnetic ordering temperatures of 1178 K for Ho 2 Co 17 and 335 K for Ho 2 Fe 17 were determined by the strong positive 3d-3d exchange. (Auth.)

New tetragonal derivatives of cubic NaZn{sub 13}-type structure: RNi{sub 6}Si{sub 6} compounds, crystal structure and magnetic ordering (R=Y, La, Ce, Sm, Gd–Yb)

Energy Technology Data Exchange (ETDEWEB)

Pani, M.; Manfrinetti, P.; Provino, A. [INFM and Dipartimento di Chimica e Chimica Industriale, Universita‘ di Genova, Via Dodecaneso 31, 16146 Genova (Italy); Yuan, Fang; Mozharivskyj, Y. [Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada L8S 4M1 (Canada); 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.; Garshev, 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); Isnard, O. [Université Grenoble Alpes, Inst NEEL, BP166, F-38042 Grenoble (France); CNRS, Institut NEEL, 25 rue des martyrs, F-38042 Grenoble (France)

2014-02-15

Novel RNi{sub 6}Si{sub 6} compounds adopt the new CeNi{sub 6}Si{sub 6}-type structure for R=La–Ce (tP52, space group P4/nbm N 125-1) and new YNi{sub 6}Si{sub 6}-type structure for R=Y, Sm, Gd–Yb (tP52, space group P4{sup ¯}b2N 117) that are tetragonal derivative of NaZn{sub 13}-type structure, like LaCo{sub 9}Si{sub 4}-type. The CeNi{sub 6}Si{sub 6}, GdNi{sub 6}Si{sub 6}, TbNi{sub 6}Si{sub 6}, DyNi{sub 6}Si{sub 6} and HoNi{sub 6}Si{sub 6} compounds are Curie–Weiss paramagnets down to ∼30 K, and do not order magnetically down to 5 K. However, the inverse paramagnetic susceptibility of LaNi{sub 6}Si{sub 6} does not follow Curie–Weiss law. The DyNi{sub 6}Si{sub 6} shows ferromagnetic-like saturation behaviour at 5 K in applied fields of 50 kOe, giving rise to a magnetic moment value of 6.5 μ{sub B}/f.u. in 50 kOe. The powder neutron diffraction study in zero applied filed indicates square modulated the c-collinear antiferromagnetic ordering of TbNi{sub 6}Si{sub 6} with K=[±1/4, ±1/4, 0] wave vector below ∼10 K. - Graphical abstract: Novel (La, Ce)Ni{sub 6}Si{sub 6} compounds adopt the new CeNi{sub 6}Si{sub 6}-type structure and (Y, Sm, Gd–Yb) adopt the new YNi{sub 6}Si{sub 6}-type structure that are tetragonal derivative of NaZn{sub 13}-type structure, like LaCo{sub 9}Si{sub 4}-type. The CeNi{sub 6}Si{sub 6}, GdNi{sub 6}Si{sub 6}, TbNi{sub 6}Si{sub 6}, DyNi{sub 6}Si{sub 6} and HoNi{sub 6}Si{sub 6} compounds are Curie–Weiss paramagnets down to ∼30 K, and do not order magnetically down to 4.2 K. The powder neutron diffraction study in zero applied filed indicates square modulated the c-collinear antiferromagnetic ordering of TbNi{sub 6}Si{sub 6} with K=[±1/4, ±1/4, 0] wave vector below ∼10 K. Display Omitted - Highlights: • The new (La, Ce)Ni{sub 6}Si{sub 6} compounds adopt the new CeNi{sub 6}Si{sub 6}-type structure. • The new (Y, Sm, Gd–Yb)Ni{sub 6}Si{sub 6} compounds adopt the new YNi{sub 6}Si{sub 6}-type structure. • TbNi{sub 6}Si

Magnetic field-induced elastic bending in bilayers of Tb{sub 1−x}Dy{sub x}Fe{sub 2−y} and Pb(Zr{sub 1−z}Ti{sub z})O{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Jin, Tao; Qichao, Wu; Ning, Zhang, E-mail: zhangning@njnu.edu.cn

2014-09-01

Magnetic field-induced strain in the magnetoelectric bilayers of Tb{sub 1−x}Dy{sub x}Fe{sub 2−y} and Pb(Zr{sub 1−z}Ti{sub z})O{sub 3} was studied. A butterfly shaped strain curve was observed on the surface of Pb(Zr{sub 1−z}Ti{sub z})O{sub 3}. The shape of the strain curve was found to be related to the sample thickness and the volume fraction occupied by the ferroelectrics in the bilayer. Theoretical analysis and experimental results showed that magnetoelastic bending in the bilayer composites was largely responsible for the butterfly strain curve. - Highlights: • Butterfly strain curves were observed on the PZT surface for bilayers of TDF and PZT. • The strain curve is related to the sample thickness and the volume fraction of the PZT. • A physics model depicting the field-controlled bending of the bilayers was developed. • The magnetoelastic bending was found to account for the butterfly strain curve.

Proceedings of the 9th workshop on the mass of the electron neutrino

International Nuclear Information System (INIS)

Yasumi, Shinjiro

1984-03-01

The 9th workshop on the mass of electron neutrinos was held at KEK, Japan. The experimental studies concerning the M-shell of Dy atoms for the measurement of the mass of electron neutrinos were presented at the workshop. The reports included in this proceedings concern windowless Si(Li) detectors, the irradiation technique to make Ho-163 radioactive sources, high purity Ho-163 sources, the M X-ray spectra of rare earth atoms, the study on the M-shell of Dy atoms by using monochromatic X-ray from the KEK PF (Photon Factory), the absolute measurement of photon beam flux, the angular distribution of M X-ray accompanying the photoelectric effect caused by linearly polarized photons, the X-ray spectrum around the 5p to 3s peak accompanying the decay of Ho-163, and the data of nuclear matrix elements of the electron capture decay of Ho-163. The reports presented at the previous workshop are also included in this proceedings. They concern the theoretical calculation of the M X-ray spectrum of Dy, the mass measurement of electron neutrinos, the X-ray spectrum of Ho-163 sources, the amount of Dy-164 contained in Ho-163 samples, and the isotope dilution mass spectrometry. (Kato, T.)

Výchova ke zdraví v učebnicích 1. stupně ZŠ: výsledky analýzy didaktického aparátu učebnic prvouky/přírodovědy/Health education in primary school textbooks – results of a content analysis

Directory of Open Access Journals (Sweden)

Markéta Hrozová

2015-02-01

Full Text Available Cílem empirické studie je prezentace výsledků obsahové analýzy didaktického aparátu učebnic a cvičebnic školního vzdělávacího předmětu prvouka/přírodověda určených pro žáky 1. stupně základních škol z hlediska jejich zaměření na výchovu ke zdraví. V první části studie prezentujeme teoretický základ našeho výzkumu, který spočíval ve vymezení analytických kategorií vyplývajících z holistického pojetí zdraví. V druhé části představujeme cíle a metody výzkumu, výzkumný vzorek sestávající z pěti současných ucelených učebnicových řad učebnic prvouky/ přírodovědy (38 učebnic/cvičebnic; 3136 zkoumaných jednotek, tedy otázek, námětů a úkolů zařazených do učebnic platných pro 1. stupeň základního vzdělávání. Třetí část je věnována výsledkům analýzy, která poukázala na významné rozdíly v prezentaci učiva v oblasti výchova ke zdraví. Z výsledků vyplývá nereflektování holistického pojetí zdraví v jeho plném rozsahu, majoritní zastoupení biologického kontextu zdraví ve zkoumaných učebnicích. Holistické pojetí zdraví nejvíce reflektují učebnice druhých ročníků. Dále poukazujeme na významné rozdíly ve strukturaci učiva v rámci jednotlivých učebnicových řad (absence tematiky zdraví ve většině zkoumaných učebnic 4. ročníků a nestabilitu v distribuci tematických celků zkoumaného vzorku učebnic. V závěru studie (čtvrtá a pátá část jsou diskutovány výsledky, možnosti a limity studie a představujeme eventuality navazujícího výzkumného šetření.

Heat capacity of RFe{sub x}Mn{sub 12-x} (R = Gd, Tb and Dy) compounds: wiping out a cooperative 4f-4f exchange interaction by breaking the 3d-4f magnetic symmetry

Energy Technology Data Exchange (ETDEWEB)

Pique, C; Blanco, J A; Abad, E [Departamento de Fisica, Universidad de Oviedo, Campus de Viesques, E-33204 Gijon (Spain); Burriel, R; Artigas, M [Instituto de Ciencia de Materiales de Aragon (CSIC-Universidad de Zaragoza), E-50009 Zaragoza (Spain); Fernandez-RodrIguez, J [European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex (France)], E-mail: pique@uniovi.es

2008-08-27

Using adiabatic calorimetry the heat capacity of a series of RFe{sub x}Mn{sub 12-x} (R = Gd, Tb and Dy) compounds has been measured from 3 to 350 K. The substitution of Fe for Mn in RFe{sub x}Mn{sub 12-x} influences both the magnetic interactions on the 3d sublattice and the magnetism of R (the Neel temperature doubles on going from x = 0 to 6 and the compounds become ferromagnetic for x = 8 with Curie temperatures of around 300 K). In pure TbMn{sub 12} the heat-capacity data shows a {lambda}-type anomaly associated with the independent cooperative magnetic ordering of the R sublattice ({approx}5 K), while the anomaly related to the Mn magnetic ordering ({approx}100 K) is rather smooth, as observed in other itinerant magnetic systems such as YMn{sub 12}. In contrast, the substitution of Fe for Mn leads, on the one hand, to a more localized magnetic behaviour of the 3d sublattice, and, on the other, to magnetic polarization effects between the 3d and 4f sublattices, together with the disappearance of the cooperative magnetic ordering of the R sublattice due to the breaking of the antiferromagnetic symmetry in the 3d sublattice. This is reflected in the heat-capacity curve through a smooth Schottky-like anomaly. In the case of Gd compounds the magnitude of the exchange molecular-field parameter has been deduced by fitting the magnetic contribution to the heat capacity within a simple mean-field model. From this analysis we found that this molecular field acting on the rare-earth site increases with the iron concentration, reaching values as large as 48 T for the concentration x = 6. A similar analysis of the heat capacity in the ordered phase on the Tb compounds also leads to an enhancement of the molecular field with increasing Fe content. These results allow checking the possible crystal-field parameters for these RFe{sub x}Mn{sub 12-x} compounds.

TB Terms

Science.gov (United States)

... sputum can also be used to do a culture. TB blood test – a test that uses a blood sample to find out if you are infected with TB bacteria. The test measures the response to TB proteins when they are mixed with a small amount of blood. Examples of these TB blood tests include QuantiFERON ® -TB ...

Complexes of heavy lanthanides with o-aminobenzoic acid

International Nuclear Information System (INIS)

Brzyska, W.; Rzaczynska, Z.

1988-01-01

Anthranilates of Tb-Lu prepared in the reaction of the rare earth hydroxides with ortho-aminobenzoic acid (anthranilic acid) have the general formula Ln(C 6 H 4 NH 2 COO) 3 centredot 2H 2 O where Ln = Tb, Dy, Ho, Er, Tm, Yb, Lu. The water molecules in the hydrated compounds are in the outer coordination sphere. On heating in air at 493 K dehydration occurs and the anhydrous anthranilates Ln(C 6 H 4 NH 2 COO) 3 are formed. On the basis of the IR spectra it was found that the metal in dihydrated anthranilates was simultaneously coordinated through amino and carboxyl groups whereas in anhydrous anthranilates only through the bidentate carboxyl group. From X-ray analysis it was stated that the anthranilates Ln(C 6 H 4 NH 2 COO) 3 centredot 2H 2 O are isostructural, whereas the anhydrous compounds Ln(C 6 H 4 NH 2 COO) 3 are isostructural in the two groups Tb-Er and Tm-Lu. (Author)

Magnetic properties of the ternary carbide DyCoC2 studied by magnetization measurements, neutron diffraction and 161Dy Moessbauer spectroscopy

International Nuclear Information System (INIS)

Amanai, H.; Onodera, H.; Ohashi, M.; Matsuo, S.; Yamauchi, H.

1995-01-01

The magnetic properties of DyCoC 2 have been investigated by means of magnetization measurements, powder neutron diffraction and 161 Dy Moessbauer spectroscopy. The magnetization versus temperature curves of a single-crystalline sample reveal that the magnetic structure of DyCoC 2 is a simple collinear ferromagnetic one below T C =10.0 K. At 4.2 K, the magnitude of the Dy moment is 8.7(1)μ B , whose direction is defined by an angle of 38.0(5) from the a-axis toward the c-axis. The magnetic structure and the magnitude of the moment are also confirmed by the results of powder neutron diffraction experiments and 161 Dy Moessbauer spectroscopy, respectively. ((orig.))

Synthesis, Structure, and Magnetism of Tris(amide) {Ln[N(SiMe3)2]3}1- Complexes of the Non-Traditional +2 Lanthanide Ions.

Science.gov (United States)

Ryan, Austin Jack; Darago, Lucy E; Balasubramini, Sree Ganesh; Chen, Guo P; Ziller, Joseph W; Furche, Filipp; Long, Jeffrey R; Evans, William J

2018-02-28

A new series of Ln2+ complexes has been synthesized that overturns two previous generalizations in rare-earth metal reduction chemistry: that amide ligands do not form isolable complexes of the highly-reducing non-traditional Ln2+ ions and that yttrium is a good model for the late lanthanides in these reductive reactions. Reduction of Ln(NR2)3 (R = SiMe3) complexes in THF under Ar with M = K or Rb in the presence of 2.2.2-cryptand (crypt) forms crystallographically-characterizable [M(crypt)][Ln(NR2)3] complexes not only for the traditional Tm2+ ion and the configurational crossover ions, Nd2+ and Dy2+, but also for the non-traditional Gd2+, Tb2+, Ho2+, and Er2+ ions. Crystallographic data as well as UV-visible, magnetic susceptibility, and density functional theory studies are consistent with the accessibility of 4fn5d1 configurations for Ln2+ ions in this tris(silylamide) ligand environment. The Dy2+ complex, [K(crypt)][Dy(NR2)3], has a higher magnetic moment than previously observed for any monometallic complex: 11.67 µB. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Faraday effect in γ-Dy2S3 and c-Dy2O3 paramagnetic crystals

International Nuclear Information System (INIS)

Shelykh, A.I.

1987-01-01

Studies of spectral and temperature dependences of Faraday effect in γ-Dy 2 S 3 and C-Dy 2 O 3 paramagnetic crystals are conducted. Paramagnetism of these crystals is brought about by Dy 3+ ions. Estimation of the effect of such factors as the value of paramagnetic ion concentration, width of the forbidden band, crystallochemical composition on magnetooptical effect in the considered compounds of dysprosium is carried out on the basis of the obtained experimental data and theoretical analysis. It is shown, that the Faraday effect in the considered compounds of dysprosium as well as the value of paramagnetic moment may be regarded rather accurately in free ion approximation

Room-temperature ferromagnetism in Dy films doped with Ni

International Nuclear Information System (INIS)

Edelman, I.; Ovchinnikov, S.; Markov, V.; Kosyrev, N.; Seredkin, V.; Khudjakov, A.; Bondarenko, G.; Kesler, V.

2008-01-01

Temperature, magnetic field and spectral dependences of magneto-optical effects (MOEs) in bi-layer films Dy (1-x) Ni x -Ni and Dy (1-x) (NiFe) x -NiFe were investigated, x changes from 0 to 0.06. Peculiar behavior of the MOEs was revealed at temperatures essentially exceeding the Curie temperature of bulk Dy which is explained by the magnetic ordering of the Dy layer containing Ni under the action of two factors: Ni impurities distributed homogeneously over the whole Dy layer and atomic contact of this layer with continues Ni layer. The mechanism of the magnetic ordering is suggested to be associated with the change of the density of states of the alloy Dy (1-x) Ni x owing to hybridization with narrow peaks near the Fermi level character for Ni

DySectAPI: Scalable Prescriptive Debugging

DEFF Research Database (Denmark)

Jensen, Nicklas Bo; Karlsson, Sven; Quarfot Nielsen, Niklas

We present the DySectAPI, a tool that allow users to construct probe trees for automatic, event-driven debugging at scale. The traditional, interactive debugging model, whereby users manually step through and inspect their application, does not scale well even for current supercomputers. While...... lightweight debugging models scale well, they can currently only debug a subset of bug classes. DySectAPI fills the gap between these two approaches with a novel user-guided approach. Using both experimental results and analytical modeling we show how DySectAPI scales and can run with a low overhead...

Effect of Ligand Substitution around the Dy(III) on the SMM Properties of Dual-Luminescent Zn-Dy and Zn-Dy-Zn Complexes with Large Anisotropy Energy Barriers: A Combined Theoretical and Experimental Magnetostructural Study.

Science.gov (United States)

Costes, Jean Pierre; Titos-Padilla, Silvia; Oyarzabal, Itziar; Gupta, Tulika; Duhayon, Carine; Rajaraman, Gopalan; Colacio, Enrique

2016-05-02

The new dinuclear Zn(II)-Dy(III) and trinuclear Zn(II)-Dy(III)-Zn(II) complexes of formula [(LZnBrDy(ovan) (NO3)(H2O)](H2O)·0.5(MeOH) (1) and [(L(1)ZnBr)2Dy(MeOH)2](ClO4) (3) (L and L(1) are the dideprotonated forms of the N,N'-2,2-dimethylpropylenedi(3-methoxysalicylideneiminato and 2-{(E)-[(3-{[(2E,3E)-3-(hydroxyimino)butan-2-ylidene ]amino}-2,2-dimethylpropyl)imino]methyl}-6-methoxyphenol Schiff base compartmental ligands, respectively) have been prepared and magnetostructurally characterized. The X-ray structure of 1 indicates that the Dy(III) ion exhibits a DyO9 coordination sphere, which is made from four O atoms coming from the compartmental ligand (two methoxy terminal groups and two phenoxido bridging groups connecting Zn(II) and Dy(III) ions), other four atoms belonging to the chelating nitrato and ovanillin ligands, and the last one coming to the coordinated water molecule. The structure of 3 shows the central Dy(III) ion surrounded by two L(1)Zn units, so that the Dy(III) and Zn(II) ions are linked by phenoxido/oximato bridging groups. The Dy ion is eight-coordinated by the six O atoms afforded by two L(1) ligands and two O atoms coming from two methanol molecules. Alternating current (AC) dynamic magnetic measurements of 1, 3, and the previously reported dinuclear [LZnClDy(thd)2] (2) complex (where thd = 2,2,6,6-tetramethyl-3,5-heptanedionato ligand) indicate single molecule magnet (SMM) behavior for all these complexes with large thermal energy barriers for the reversal of the magnetization and butterfly-shaped hysteresis loops at 2 K. Ab initio calculations on 1-3 show a pure Ising ground state for all of them, which induces almost completely suppressed quantum tunnelling magnetization (QTM), and thermally assisted quantum tunnelling magnetization (TA-QTM) relaxations via the first excited Kramers doublet, leading to large energy barriers, thus supporting the observation of SMM behavior. The comparison between the experimental and theoretical

Synthesis, structure and magnetic properties of DyAl2 nanoparticles

International Nuclear Information System (INIS)

Zhang, W.S.; Brueck, E.; Zhang, Z.D.; Tegus, O.; Li, W.F.; Si, P.Z.; Geng, D.Y.; Klaasse, J.C.P.; Buschow, K.H.J.

2006-01-01

DyAl 2 nanoparticles have been prepared by means of arc discharge in a mixture of argon and hydrogen gas. The structure of DyAl 2 nanoparticles is studied by means of X-ray diffraction, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. X-ray photoelectron spectroscopy shows that the as-prepared DyAl 2 nanoparticles are coated with a layer of Al 2 O 3 phase on the surface, and their sizes vary from 20 nm to about 100 nm. The DyAl 2 nanoparticles exhibit ferromagnetic properties that are different from bulk DyAl 2 compound. The gradual decrease of the magnetization with increasing temperature in a wide temperature range reveals the size distribution of the DyAl 2 nanoparticles. The magnetic-entropy changes are derived from the isothermal magnetization curves measured at different temperatures. The magnetic-entropy change of the DyAl 2 nanoparticles is lower than that of the bulk DyAl 2 material but has a broadened peak

Search for superdeformed bands in {sup 154}Dy

Energy Technology Data Exchange (ETDEWEB)

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

1995-08-01

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

Relativistic model-potential oscillator strengths and transition probabilities for 4fsup(n)6s-4fsup(n)6p transitions in Eu(II), Tb(II), and Ho(II) in J1j coupling

International Nuclear Information System (INIS)

Migdalek, J.

1984-01-01

The lowest 4fsup(n)6s-4fsup(n)6p transitions are studied for the Eu(II) (n=7), Tb(II) (n=9), and Ho(II) (n=11) spectra, where the J 1 J coupling is an acceptable approximation. The relativistic radial integrals, required to evaluate the oscillator strengths and transition probabilities, are calculated with the model-potential method, which includes also core-polarization effects. The similarities observed in oscillator strengths for transitions with given ΔJ but different J values are discussed and explained. The computed oscillator strengths are compared with those obtained with the Coulomb approximation and it is found that the latter are only 11-12% lower. The core polarization influence on oscillator strengths is also investigated and the 19-21% decrease in oscillator strengths due to this effect is predicted. This result may, however, be overestimated because of some deficiencies in our procedure. (author)

Room-temperature ferromagnetism in Dy films doped with Ni

Energy Technology Data Exchange (ETDEWEB)

Edelman, I. [Kirensky Institute of Physics, Siberian Division, Russian Academy of Sciences, Akademgorodok, Krasnoyarsk 660036 (Russian Federation)], E-mail: ise@iph.krasn.ru; Ovchinnikov, S. [Kirensky Institute of Physics, Siberian Division, Russian Academy of Sciences, Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Siberian Federal University, Av. Svobodnyi 71, Krasnoyarsk 660074 (Russian Federation); Markov, V.; Kosyrev, N.; Seredkin, V.; Khudjakov, A.; Bondarenko, G. [Kirensky Institute of Physics, Siberian Division, Russian Academy of Sciences, Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Kesler, V. [Institute of Semiconductor Physics, Siberian Division, Russian Academy of Sciences, Av. Akademika Lavrent' eva 13, Novosibirsk 630090 (Russian Federation)

2008-09-01

Temperature, magnetic field and spectral dependences of magneto-optical effects (MOEs) in bi-layer films Dy{sub (1-x)}Ni{sub x}-Ni and Dy{sub (1-x)}(NiFe){sub x}-NiFe were investigated, x changes from 0 to 0.06. Peculiar behavior of the MOEs was revealed at temperatures essentially exceeding the Curie temperature of bulk Dy which is explained by the magnetic ordering of the Dy layer containing Ni under the action of two factors: Ni impurities distributed homogeneously over the whole Dy layer and atomic contact of this layer with continues Ni layer. The mechanism of the magnetic ordering is suggested to be associated with the change of the density of states of the alloy Dy{sub (1-x)}Ni{sub x} owing to hybridization with narrow peaks near the Fermi level character for Ni.

Heightened vulnerability to MDR-TB epidemics after controlling drug-susceptible TB.

Directory of Open Access Journals (Sweden)

Jason D Bishai

2010-09-01

Full Text Available Prior infection with one strain TB has been linked with diminished likelihood of re-infection by a new strain. This paper attempts to determine the role of declining prevalence of drug-susceptible TB in enabling future epidemics of MDR-TB.A computer simulation of MDR-TB epidemics was developed using an agent-based model platform programmed in NetLogo (See http://mdr.tbtools.org/. Eighty-one scenarios were created, varying levels of treatment quality, diagnostic accuracy, microbial fitness cost, and the degree of immunogenicity elicited by drug-susceptible TB. Outcome measures were the number of independent MDR-TB cases per trial and the proportion of trials resulting in MDR-TB epidemics for a 500 year period after drug therapy for TB is introduced.MDR-TB epidemics propagated more extensively after TB prevalence had fallen. At a case detection rate of 75%, improving therapeutic compliance from 50% to 75% can reduce the probability of an epidemic from 45% to 15%. Paradoxically, improving the case-detection rate from 50% to 75% when compliance with DOT is constant at 75% increases the probability of MDR-TB epidemics from 3% to 45%.The ability of MDR-TB to spread depends on the prevalence of drug-susceptible TB. Immunologic protection conferred by exposure to drug-susceptible TB can be a crucial factor that prevents MDR-TB epidemics when TB treatment is poor. Any single population that successfully reduces its burden of drug-susceptible TB will have reduced herd immunity to externally or internally introduced strains of MDR-TB and can experience heightened vulnerability to an epidemic. Since countries with good TB control may be more vulnerable, their self interest dictates greater promotion of case detection and DOTS implementation in countries with poor control to control their risk of MDR-TB.

Measurement of 160Tb and 161Tb in nuclear forensics samples

International Nuclear Information System (INIS)

Jiang, J.; Davies, A.V.; Britton, R.E.

2017-01-01

160 Tb and 161 Tb are important radionuclides to measure when analysing a Nuclear Forensics sample. An analytical method for the measurement of both 160 Tb and 161 Tb was developed in this study. Terbium was separated and purified using exchange resin and TrisKem LN Resin. The purified fraction containing 160 Tb and 161 Tb was measured by gamma spectrometry and liquid scintillation counting. The counting efficiencies of 160 Tb and 161 Tb were determined using the CIEMAT/NIST efficiency tracing method. The LSC count rate ratio, R160 Tb /R161 Tb , on the reference date was determined by sequential counting and calculated using a custom script based on their half-lives. (author)

Rare earth and precious elements in the urban sewage sludge and lake surface sediments under anthropogenic influence in the Republic of Benin.

Science.gov (United States)

Yessoufou, Arouna; Ifon, Binessi Edouard; Suanon, Fidèle; Dimon, Biaou; Sun, Qian; Dedjiho, Comlan Achille; Mama, Daouda; Yu, Chang-Ping

2017-11-09

Nowadays, sewage sludge and water bodies are subjected to heavy pollution due to rapid population growth and urbanization. Heavy metal pollution represents one of the main challenges threatening our environment and the ecosystem. The present work aims to evaluate the contamination state of the sewage sludge and lake sediments in the Republic of Benin. Twenty metallic elements including 15 rare earth elements (Eu, Sb, Cs, Nd, Pr, Gd, La, Ce, Tb, Sm, Dy, Ho, Eu, Yb, and Lu) and five precious elements (Ag, Au, Pd, Pt, and Ru) were investigated using inductive plasma-mass spectrometry. Results showed broad range concentrations of the elements. Ce, La, and Nd were present in both sediments and sewage sludge at concentrations ranging 5.80-41.30 mg/kg dry matter (DM), 3.23-15.60 mg/kg DM, and 2.74-19.26 mg/kg DM, respectively. Pr, Sm, Gd, Tb, Dy, Eu, Er, Yb, Cs, Ho, and Tm concentrations were lower (0.02-5.94 mg/kg DM). Among precious elements, Ag was detected at the highest concentration in all sites (0.43-4.72 mg/kg DM), followed by Pd (0.20-0.57 mg/kg DM) and Au (0.01-0.57 mg/kg DM). Ru and Pt concentrations were sewage sludge. This revealed a growing anthropogenic input which was also implied by principal component analysis. The evaluation of pollution loading index (PLI) indicated a moderate to strong contamination (0.12 ≤ PLI ≤ 0.58; 37 ≤ PLI ≤ 114, respectively, for rare earth elements and precious elements), while the degree of contamination indicated a moderate polymetallic contamination for rare earth elements and significant contamination for precious elements.

Improving the diagnosis of pulmonary tuberculosis in HIV-infected individuals in Ho Chi Minh City, Viet Nam.

Science.gov (United States)

Nguyen, D T M; Hung, N Q; Giang, L T; Dung, N H; Lan, N T N; Lan, N N; Yen, N T B; Bang, N D; Ngoc, D V; Trinh, L T T; Beasley, R P; Ford, C E; Hwang, L-Y; Graviss, E A

2011-11-01

District 6, An Hoa Clinic in Ho Chi Minh City (HCMC), Viet Nam. To evaluate the performance of various algorithms in tuberculosis (TB) screening and diagnosis in a human immunodeficiency virus (HIV) infected population in HCMC, Viet Nam. A cross-sectional study of 397 consecutive HIV-infected patients seeking care at the An Hoa Clinic from August 2009 to June 2010. Data on participant demographics, clinical status, chest radiography (CXR) and laboratory results were collected. A multiple logistic regression model was developed to assess the association of covariates and pulmonary TB (PTB). The prevalence of sputum culture-confirmed PTB, acid-fast bacilli (AFB) positive TB, and multidrugresistant TB among the 397 HIV-infected patients was respectively 7%, 2%, and 0.3%. Adjusted odds ratios for low CD4+ cell count, positive sputum smear, and CXR to positive sputum culture were respectively 3.17, 32.04 and 4.28. Clinical findings alone had poor sensitivity, but combining CD4+ cell count, AFB sputum smear and CXR had a more accurate diagnostic performance. Results suggest that symptom screening had poor clinical performance, and support the routine use of sputum culture to improve the detection of TB disease in HIV-infected individuals in Viet Nam. However, when routine sputum culture is not available, an algorithm combining CD4+ cell count, AFB sputum smear and CXR is recommended for diagnosing PTB.

Some Limitations in the Use of Plastic and Dyed Plastic Dosimeters

DEFF Research Database (Denmark)

Miller, Arne; Bjergbakke, Erling; McLaughlin, W. L.

1975-01-01

Several practical plastic and dyed plastic dosimeters were examined under irradiation conditions similar to those used for radiation processing of materials. Cellulose triacetate, polymethyl methacrylate, polyvinyl chloride, dyed polymethyl methacrylate, dyed Cellophane and dyed Nylon were given...

TB or not TB?: a case of isolated testicular TB with scrotal involvement.

LENUS (Irish Health Repository)

Bhargava, A

2009-06-01

Despite the genitourinary tract being the most common site affected by extrapulmonary TB, isolated testicular TB remains a rare clinical entity. In patients with co-morbidities such as hepatic impairment, treatment proves a challenge, as first-line hepatotoxic pharmaceuticals are contraindicated. Here, we report a case of isolated testicular TB with scrotal involvement, on a background of hepatic dysfunction.

Investigation of local magnetism in RZn (R = Ce, Gd, Tb, Dy) and GdCu intermetallic compounds using perturbed angular correlation gamma-gamma spectroscopy; Investigacao do magnetismo local em compostos intermetalicos do tipo RZn (R = Ce, Gd, Tb, Dy) e GdCu pela espectroscopia de correlacao angular gama-gama perturbada

Energy Technology Data Exchange (ETDEWEB)

Santos, Brianna Bosch dos

2010-07-01

This work presents, from a microscopic point of view, a systematic study of the local magnetism in RZn (R = Ce, Gd, Tb, Dy) and GdCu intermetallic compounds through measurements of hyperfine interactions using the Perturbed Angular Correlation Gamma- Gamma Spectroscopy technique with {sup 111}In {yields} {sup 111}Cd and {sup 140}La {yields} {sup 140}Ce as probe nuclei. As the magnetism in these compounds originates from the 4f electrons of the rare-earth elements it is interesting to observe in a systematic study of RZn compounds the behavior of the magnetic hyperfine field with the variation of the number of 4f electrons in the R element. The use of probe nuclei {sup 140}La {yields} {sup 140}Ce is interesting because Ce{sup +3} ion posses one 4f electron which may contribute to the total hyperfine field, and the results showed anomalous behavior. The results for {sup 111}Cd probe showed that the temperature dependence of the magnetic hyperfine field follows the Brillouin function, and the magnetic hyperfine field decreases linearly with increase of the atomic number of rare earth when plotted as a function of the rare-earth J spin projection, showing that the main contribution to the magnetic hyperfine field in RZn compounds comes from the polarization of the conduction electrons. The results for the electric field gradient measured with {sup 111}Cd for all compounds showed a strong decrease with the atomic number of the rare-earth element. We have therefore assumed that the major contribution to the electric field gradient originates from the 4f electrons of the rare-earths. The measurements of the electric field gradient for GdCu with {sup 111}Cd, after temperature decreases and increases again showed that two different structures, CsCl-type cubic and FeB-type orthorhombic structures co-exist. Finally, it is the first time that measurements of hyperfine parameters have been carried out with theses two probe nuclei in the studied RZn. (author)

Find TB. Treat TB. Working together to eliminate TB.

Centers for Disease Control (CDC) Podcasts

2014-02-26

In this podcast, Dr. Sundari Mase, Medical Team Lead in the Field Services and Evaluation Branch in the Division of Tuberculosis Elimination, discusses World TB Day and the 2014 theme.  Created: 2/26/2014 by National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP).   Date Released: 2/26/2014.

Investigation of thermal expansion and compressibility of rare-earth orthovanadates using a dielectric chemical bond method.

Science.gov (United States)

Zhang, Siyuan; Zhou, Shihong; Li, Huaiyong; Li, Ling

2008-09-01

The chemical bond properties, lattice energies, linear expansion coefficients, and mechanical properties of ReVO 4 (Re = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, Y) are investigated systematically by the dielectric chemical bond theory. The calculated results show that the covalencies of Re-O bonds are increasing slightly from La to Lu and that the covalencies of V-O bonds in crystals are decreasing slightly from La to Lu. The linear expansion coefficients decrease progressively from LaVO 4 to LuVO 4; on the contrary, the bulk moduli increase progressively. Our calculated results are in good agreement with some experimental values for linear expansion coefficients and bulk moduli.

The first example of erbium triple-stranded helicates displaying SMM behaviour.

Science.gov (United States)

Gorczyński, Adam; Kubicki, Maciej; Pinkowicz, Dawid; Pełka, Robert; Patroniak, Violetta; Podgajny, Robert

2015-10-14

A series of isostructural C3-symmetrical triple stranded dinuclear lanthanide [Ln2L3](NO3)3 molecules have been synthesized using subcomponent self-assembly of Ln(NO3)3 with 2-(methylhydrazino)benzimidazole and 4-tert-butyl-2,6-diformylphenol, where Ln = Tb (1), Dy (2), Ho (3), Er (4), Tm (5), and Yb (6). The temperature dependent and field dependent magnetic properties of 1-6 were modeled using the van Vleck approximation including the crystal field term HCF, the super-exchange term HSE and the Zeeman term HZE. Ferromagnetic interactions were found in 1, 2, 4 and 6, while antiferromagnetic interactions were found in 3 and 5. The erbium analogue reveals field induced SMM behaviour.

Inductively coupled plasma optical emission spectrometry analysis of lanthanum, samarium and gadolinium oxides for rare earths impurities

International Nuclear Information System (INIS)

Reino, L.C.P.; Lordello, A.R.

1990-09-01

An inductively coupled plasma optical emission spectrometry method is described for the determination of Sm, Eu, La, Gd, Dy, Pr, Ho, Nd, Tb and Y in purified oxides of lanthanum, samarium and gadolinium. The method enables a simple, precise and readily available determination. Dissolution of the samples is achieved with diluted hydrochloric acid (1:1). The solutions are diluted to volume for a concentration of 1mg/ml. The lowest determination limit is 0,01% for most elements and 0,05 or 0,1% for a few rare earths in samarium and gadolinium matrices. Lanthanum, Samarium and Gadolinium concentrates with purity grade of 99,9%, 99,6% and 99,8%, respectively, can be analysed by this procedure. (author)

The ternary systems Sc-Sm(Dy)-Si at 870 K

International Nuclear Information System (INIS)

Kotur, B.Ya.; Mokra, I.Ya.; Toporinskij, A.Ya.

1991-01-01

Isothermal cross sections of the ternary systems Sc-Sm-Si and Sc-Dy-Si at 870 K have been plotted. Investigation of scandium and disprosium in ternary systems have been examined by X-ray diffraction and microstructure analysis. Besides literary data on binary systems Sc-Si, Sm-Si, Dy-Si have been used. Formation of limited (Sc-Sm-Si, Sc-Dy-Si) and continuous (Sc-Dy-Si) solid solutions based on bisilicides of Sc and Sm(Dy) is discovered. Two and five ternary compounds in Sc-Sm-Si and Sc-Dy-Si systems have been determined and their crystal structure has been established. When investigating of Sc-(rare earth element)-Si ternary systems and should take into account the specific interaction of scandium and samarium with REE

Microstructures and mechanical properties of Mg–Zn–Zr–Dy ...

Indian Academy of Sciences (India)

Microstructures and phase compositions of as-cast and extruded ZK60–Dy ( = 0–5) alloys were analysed by optical microscope, scanning electron microscope, X-ray diffraction and differential scanning calorimetry. Meanwhile, the tensile mechanical property was tested.With increasing Dy content, Mg–Zn–Dy new phase ...

Mezinárodní spolupráce v dějinách vědy středoevropského prostoru

Czech Academy of Sciences Publication Activity Database

Štrbáňová, Soňa

-, č. 9 (2015), s. 24-26 ISSN 1210-9525. [Hledání jazyka vědy, český případ. Praha, 21.05.2015 -] Institutional support: RVO:68378114 Keywords : history of science * cooperation in history of science * national style in science Subject RIV: AB - History

Luminescence studies on Dy3+ and Dy3+:Eu3+ co-doped boro-phosphate glasses for WLED applications

Science.gov (United States)

Vijayakumar, M.; Uma, V.; Arunkumar, S.; Marimuthu, K.

2015-06-01

Dy3+ and Dy3+:Eu3+ co-doped boro-phosphate glasses have been prepared and optically characterized using absorption, luminescence and decay measurements. The Nephelauxetic ratios (β), Bonding parameters (δ) and Judd-Ofelt (JO) intensity parameters Ωλ (λ = 2, 4 and 6) were calculated to study the nature of the environment around the RE3+ ions in the prepared glasses. The yellow to blue (Y/B) intensity ratio and the chromaticity color coordinates were calculated from the luminescence measurements. The lifetimes of the 4F9/2 excited level were measured using decay curves and is found to decrease in the Dy3+:Eu3+ co-doped glass due to the occurrence of resonant energy transfer between Dy3+-Eu3+ ions and the non-exponential decay rates have been fitted with Inokuti-Hirayama (IH) model. The decay curves are well fitted for S= 6 suggesting that the interaction between active ions for the energy transfer is of dipole-dipole nature.

Thermoluminescence properties of Al{sub 2}O{sub 3}:Tb nanoparticles irradiated by gamma rays and 85 MeV C{sup 6+} ion beam

Energy Technology Data Exchange (ETDEWEB)

Salah, Numan, E-mail: nsalah@kau.edu.sa [Center of Nanotechnology, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Alharbi, Najlaa D. [Sciences Faculty for Girls, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Habib, Sami S. [Center of Nanotechnology, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Lochab, S.P. [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

2015-11-15

Carbon ions beam is recently recognized as an ideal cancer treatment modality, because of its excellent local tumor control. These ions have a high relative biological effectiveness resulting from high linear energy transfer (LET) and their sharp Bragg peak. However, the dose of those energetic ions needs to be measured with great precision using a proper dosimeter. Aluminum Oxide (Al{sub 2}O{sub 3}) is a highly luminescent phosphor widely used for radiation dosimetry using thermoluminesence (TL) technique. In this work nanoparticles of this material activated by different elements like Eu, Tb, Dy, Cu and Ag were evaluated for their TL response to gamma rays irradiation. Tb doped sample is found to be the most sensitive sample, which could be selected for exposure to 85 MeV C{sup 6+} ion beam in the fluence range 10{sup 9}–10{sup 13} ions/cm{sup 2}. The obtained result shows that C ion beam irradiated sample has a simple glow curve structure with a prominent glow peak at around 230 °C. This glow curve has a dosimetric peak better than those induced by gamma rays. This glow peak exhibits a linear response in the range 10{sup 9}–10{sup 11} ions/cm{sup 2}, corresponding to the equivalent absorbed doses 0.285–28.5 kGy. The absorbed doses, penetration depths and main energy loss were calculated using TRIM code based on the Monte Carlo simulation. The wide linear response of Al{sub 2}O{sub 3}:Tb nanoparticles along with the low fading makes this low cost nanomaterial a good candidate for C ion beam dosimetry. - Highlights: • Nanoparticles of Al{sub 2}O{sub 3} doped with Eu, Tb, Dy, Cu and Ag were synthesised. • They were evaluated for their TL response to gamma rays and C ion beam irradiation. • Tb doped sample is the most sensitive sample to gamma rays. • Al{sub 2}O{sub 3}:Tb was exposed to 85 MeV C{sup 6+} ion beam in the fluence range 10{sup 9}-10{sup 13} ions/cm{sup 2}. • The glow peak induced by C ions has a linear response in the range 10{sup 9

Ferromagnetism in some semi-conducting heavy rare-earth molybdates

International Nuclear Information System (INIS)

Lal, H.B.; Pandey, R.N.

1978-01-01

Measurements of the magnetic susceptibility of powdered samples of Dy 2 (MoO 4 ) 3 , Ho 2 (MoO 4 ) 3 and Er 2 (MoO 4 ) 3 in the temperature range 300 to 920 K are reported. The Curie Weiss Law is obeyed and yields the magneton numbers 10.72, 10.68 and 9.68 for the Dy 3+ , Ho 3+ and Er 3+ ions, respectively, the theoretical values being 10.63, 10.60 and 9.60. The results are analysed in terms of molecular field theory and it is predicted that Dy 2 (MoO 4 ) 3 , Ho 2 (MoO 4 ) 3 and Er 2 (MoO 4 ) 3 become ferromagnetic below 12, 17 and 5 K, respectively. (orig.) [de

Studies of valence of selected rare earth silicides determined using Si K and Pd/Rh L{sub 2,3} XANES and LAPW numerical studies

Energy Technology Data Exchange (ETDEWEB)

Zajdel, P., E-mail: pawel.zajdel@us.edu.pl [Institute of Physics, University of Silesia, ul. Uniwersytecka 4, 40-007 Katowice (Poland); Kisiel, A., E-mail: andrzej.kisiel@uj.edu.pl [M. Smoluchowski Institute of Physics, Jagiellonian University, ul. Lojasiewicza 11, 30-348 Kraków (Poland); Szytuła, A., E-mail: andrzej.szytula@uj.edu.pl [M. Smoluchowski Institute of Physics, Jagiellonian University, ul. Lojasiewicza 11, 30-348 Kraków (Poland); Goraus, J., E-mail: jerzy.goraus@us.edu.pl [Institute of Physics, University of Silesia, ul. Uniwersytecka 4, 40-007 Katowice (Poland); Balerna, A., E-mail: antonella.balerna@lnf.infn.it [Laboratori Nazionali di Frascati, INFN, Lab DAPHINE-Light, Via E. Fermi 40, I-00044 Frascati (Italy); Banaś, A., E-mail: slsba@nus.edu.sg [Singapore Synchrotron Light Source, National University of Singapore, 5 Research Link, Singapore 117603 (Singapore); Starowicz, P., E-mail: pawel.starowicz@uj.edu.pl [M. Smoluchowski Institute of Physics, Jagiellonian University, ul. Lojasiewicza 11, 30-348 Kraków (Poland); Konior, J., E-mail: jerzy.konior@uj.edu.pl [M. Smoluchowski Institute of Physics, Jagiellonian University, ul. Lojasiewicza 11, 30-348 Kraków (Poland); Cinque, G., E-mail: gianfelice.cinque@diamond.ac.uk [Diamond Light Source, Harwell Campus, OX11 0DE Chilton-Didcot (United Kingdom); Grilli, A., E-mail: antonio.grilli@lnf.infn.it [Laboratori Nazionali di Frascati, INFN, Lab DAPHINE-Light, Via E. Fermi 40, I-00044 Frascati (Italy)

2015-12-01

Highlights: • The Si K and Pd L{sub 3} edges of R{sub 2}PdSi{sub 3} (R = Ce, Nd, Tb, Dy, Ho, Er) and HoRh{sub 2−x}Pd{sub x}Si{sub 2} are reported. • The R–Si bonds possess polar and 4d5s bands of Pd and Rh metallic characters. • There is no indication of Ce having a different valence than the other rare earths. • The positions and features of the calculated edges exhibit a fair agreement up to ≈10 eV. • The supercell used for Ho{sub 2}PdSi{sub 3} is good enough to reproduce the Si K edge. - Abstract: We report on the investigation of Si and Pd/Rh chemical environments using X-ray Absorption Near Edge Spectroscopy in two different families of rare earth silicides R{sub 2}PdSi{sub 3} (R = Ce, Nd, Tb, Dy, Ho, Er) and HoRh{sub 2−x}Pd{sub x}Si{sub 2} (x = 0, 0.5, 0.75, 1.0, 1.5, 1.8, 2.0). The Si K, Pd L{sub 3} and Rh L{sub 3} absorption edges were recorded in order to follow their changes upon the variation of 4f and 4d5s electron numbers. In both cases it was found that the Si K edge was shifted ≈0.5 eV toward lower energies, relative to pure silicon. In the first family, the shift decreases with increasing number of f-electrons, while the Si K edge remains constant upon rhodium–palladium substitution. In all cases the Pd L{sub 3} edge was shifted to higher energies relative to metallic Pd. No visible change in the Pd L{sub 3} position was observed either with a varying 4f electron count or upon Pd/Rh substitution. Also, the Rh L{sub 3} edge did not change. For two selected members, Ho{sub 2}PdSi{sub 3} and HoPd{sub 2}Si{sub 2}, the Wien2K’09 (LDA + U) package was used to calculate the electronic structure and the absorption edges. Si K edges were reproduced well for both compounds, while Pd L{sub 3} only exhibited a fair agreement for the second compound. This discrepancy between the Pd L{sub 3} theory and experiment for the Ho{sub 2}PdSi{sub 3} sample can be attributed to the specific ordered superstructure used in the numerical calculations

CaSO4: Dy + Teflon thermoluminescent dosemeters

International Nuclear Information System (INIS)

Campos, L.L.

1986-01-01

A pellet dosemeter of CaSO 4 : Dy + Teflon was developed at IPEN. CaSO 4 : Dy thermoluminescent phosphor, grown in the Dosimetric Materials Production Laboratory was chosen, due to its high sensitivity, ease of preparation and comparatively low cost. Pellets were produced by cold pressing and sintering a mixture of CaSO 4 : Dy and Teflon powders. Extensive work was done to study in detail all CaSO 4 : Dy pellets characteristics from the point of view of dosimetry with the purpose of introducing it in the routine use. A filter combination providing an energy independent response from 20 KeV to 1,25 MeV was obtained. The dosemeter consists of three pellets sealed between two thin plastic sheets and placed under plastic and lead filters. The combination of these tree filters allows the exposure as well as the energy determination of an unknown source. (Author) [pt

Spectroscopy and microchip laser operation of Tm, Ho:KYW crystals with different Ho concentrations

Science.gov (United States)

Gusakova, N. V.; Kurilchik, S. V.; Yasukevich, A. S.; Kisel, V. E.; Dashkevich, V. I.; Orlovich, V. A.; Pavlyuk, A. A.; Vatnik, S. M.; Bagaev, S. N.; Kuleshov, N. V.

2018-02-01

The spectroscopic properties of Tm, Ho:KYW crystals with different Ho concentrations were investigated. The diode-pumped microchip laser operation of Tm (5 at.%), Ho (0.5 at.%):KYW and Tm (5 at.%), Ho (1 at.%):KYW was demonstrated. The highest, to our knowledge, output power of 480 mW with slope efficiency of 31% for CW Tm (5 at.%), Ho (0.5 at.%):KYW microchip laser was obtained.

Testing for TB Infection

Science.gov (United States)

... Adverse Events TB Treatment of Persons Living with HIV TB Treatment and Pregnancy TB Treatment for Children Drug-Resistant TB Research TB Epidemiologic Studies Consortium Research Projects Publications TB Trials Consortium Study ...

Low-energy structure studies of odd-odd deformed nuclei and the coriolis and residual interactions

Energy Technology Data Exchange (ETDEWEB)

Dewberry, R.A.

1980-08-01

The nuclear level structure of /sup 176/Lu, /sup 170/Tm, /sup 166/Ho, and /sup 160/Tb have been studied by means of the /sup 177/Hf(t,..cap alpha..)/sup 176/Lu, /sup 171/Yb(t,..cap alpha..)/sup 170/Tm, /sup 167/Er(t,..cap alpha..)/sup 166/Ho, and /sup 161/Dy(t,..cap alpha..)/sup 160/Tb reactions and with the use of previously published (d,p) spectroscopy and gamma transitions from the (n,..gamma..) reactions. The (t,..cap alpha..) reactions have been performed and analyzed with 17 MeV tritons and the Los Alamos Q3D spectrometer. Eighty-one new rotational states in excited proton configurations or vibrational excited states are proposed. An independent parameterization of the Coriolis interaction is presented, which leads to satisfactory results in reproducing experimental single-particle transfer reaction cross-sections by theoretical calculations. The anomalous population of the excited neutron configurations (404 reduces to -624 up arrow) in /sup 176/Lu and (411 reduces to +- 512 up arrow) in /sup 170/Tm, and the anomalously low (t,..cap alpha..) cross-sections of the (411 up arrow +- 633 up arrow) configuration in /sup 166/Ho are observed. Qualitative explanation of the anomalies is presented in terms of the mixing of states which satisfy the requirement delta/sub I'/,/sub I/delta/sub K'/,/sub K/. Off-diagonal H/sub INT/ matrix elements are calculated, which show that the residual interaction cannot be used to account for the magnitude of the cross-sections observed.

Band mixing in /sup 160/Dy

Energy Technology Data Exchange (ETDEWEB)

Hasiza, M L; Singh, K; Sahota, H S [Punjabi Univ., Patiala (India). Dept. of Physics

1982-11-01

The intensities of the gamma transitions in /sup 160/Dy have been measured precisely by a 45 cc Ge(Li) detector. Unequal quadrupole moments for the ground and gamma vibrational bands have been proposed in order to remove the inconsistencies in the values of band mixing parameter Z sub(gamma) for this doubly even deformed nucleus of /sup 160/Dy.

HIV/TB co-infection:perspectives of TB patients and providers on the integrated HIV/TB pilot program in Tamilnadu, India

OpenAIRE

Lakshminarayanan, Mahalakshmi

2009-01-01

The WHO recommends routine HIV testing among TB patients as a key strategy to combat the dual HIV/TB epidemic. India has integrated its HIV and TB control programs and is offering provider initiated HIV testing for all TB patients since 2007. Using a mixed methods approach, this study aims to understand the perspectives of TB patients and providers on the integrated HIV/TB pilot program in Tamilnadu, India. A survey conducted by the Tuberculosis Research Center, India on 300 TB patients is th...

Rare earth niobate coordination polymers

Science.gov (United States)

Muniz, Collin N.; Patel, Hiral; Fast, Dylan B.; Rohwer, Lauren E. S.; Reinheimer, Eric W.; Dolgos, Michelle; Graham, Matt W.; Nyman, May

2018-03-01

Rare-earth (RE) coordination polymers are infinitely tailorable to yield luminescent materials for various applications. Here we described the synthesis of a heterometallic rare-earth coordination compound ((CH3)2SO)3(RE)NbO(C2O4)3((CH3)2SO) = dimethylsulfoxide, DMSO, (C2O2= oxalate), (RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb). The structure was obtained from single crystal X-ray diffraction of the La analogue. The Nb˭O and DMSO terminal-bonding character guides assembly of an open framework structure with noncentrosymmetric RE-coordination geometry, and large spacing between the RE centers. A second structure was observed by PXRD for the smaller rare earths (Dy, Ho, Er, Yb); this structure has not yet been determined. The materials were further characterized using FTIR, and photoluminescence measurements. Characteristic excitation and emission transitions were observed for RE = Nd, Sm, Eu, and Tb. Quantum yield (QY) measurements were performed by exciting Eu and Tb analoges at 394 nm (QY 66%) and 464 nm (QY 71%) for Eu; and 370 nm (QY=40%) for Tb. We attribute the high QY and bright luminescence to two main structure-function properties of the system; namely the absence of water in the structure, and absence of concentration quenching.

Coercivity enhancement in hot deformed Nd2Fe14B-type magnets by doping low-melting RCu alloys (R = Nd, Dy, Nd + Dy)

Science.gov (United States)

Lee, Y. I.; Huang, G. Y.; Shih, C. W.; Chang, W. C.; Chang, H. W.; You, J. S.

2017-10-01

Magnetic properties of the anisotropic NdFeB magnets prepared by hot pressing followed by die-upsetting NdFeB MQU-F powders doped with low-melting RCu alloy powders were explored, where RCu stands for Nd70Cu30, Dy70Cu30 and (Nd0.5Dy0.5)70Cu30, respectively. In addition, the post-annealing at 600 °C was employed to modify the microstructures and the magnetic properties of the hot deformed magnets. It is found that doping RCu alloy powders is effective in enhancing the coercivity of the hot deformed NdFeB magnets from 15.1 kOe to 16.3-19.5 kOe. For Nd70Cu30-doped magnets, the increment of coercivity is only 1.2 kOe. Meanwhile, Dy70Cu30-doped and (Nd0.5Dy0.5)70Cu30-doped magnets show an almost identical enhancement of coercivity of about 4.4 kOe. Importantly, the latter magnet shows a beneficial effect of reducing the usage of Dy from 1.6 wt% to 0.8 wt%. TEM analysis shows that nonmagnetic Nd, Dy and Cu appear at grain boundary and isolate the magnetic grains, leading to an enhancement of coercivity. Doping lower melting point Dy-lean (Nd0.5Dy0.5)70Cu30 powders into commercial MQU-F powders for making high coercivity hot deformed NdFeB magnets might be a potential and economic way for mass production.

Reddish-orange, neutral and warm white emissions in Eu3+, Dy3+ and Dy3+/Eu3+ doped CdO-GeO2-TeO2 glasses

Science.gov (United States)

Rodríguez-Carvajal, David A.; Meza-Rocha, A. N.; Caldiño, U.; Lozada-Morales, R.; Álvarez, E.; Zayas, Ma. E.

2016-11-01

Eu3+, Dy3+ and Dy3+/Eu3+ doped CdO-GeO2-TeO2 glasses were prepared using the melt-quenching process and analyzed by X-diffraction, Raman spectroscopy, excitation and emission spectra, and emission decay time profiles. The lack of X ray diffraction peaks revealed that all samples are amorphous. Vibrational modes associated with Tesbnd Osbnd Te and Gesbnd Osbnd Ge related bonds and molecular oxygen were detected by Raman spectroscopy. The luminescence characteristics were studied upon excitations that correspond with the emission of InGaN (370-420 nm) based LEDs. The Eu3+ singly doped glass displayed reddish-orange global emission, with x = 0.601 and y = 0.349 CIE1931 chromaticity coordinates, upon 393 nm excitation. Neutral emission with x = 0.373 and y = 0.412 CIE1931 chromaticity coordinates and correlated color temperature (CCT) of 4400 K, was achieved in the Dy3+ singly doped glass excited at 388 nm. The Dy3+/Eu3+ co-doped glass exhibited warm, neutral and soft warm white emissions with CCT values of 3435, 4153 and 2740 K, under excitations at 382, 388 and 393 nm, respectively, depending mainly on the Dy3+ and Eu3+ relative excitation. The Dy3+ excitation bands observed in the Dy3+/Eu3+ glass by monitoring the 611 nm Eu3+ emission, suggest that Dy3+ → Eu3+ energy transfer takes place, despite the fact that the Dy3+ emission decays in the Dy3+ and Dy3+/Eu3+ doped glass, remain without changes. The shortening of Eu3+ decay in presence of Dy3+ was attributed to an Eu3+ → Dy3+ non-radiative energy transfer process, which according with the Inokuti-Hirayama model might be dominated through an electric quadrupole-quadrupole interaction, with efficiency and probability of 5.5% and 51.6 s-1, respectively.

The association between ARV and TB drug resistance on TB treatment outcome among Kazakh TB/HIV patients.

Science.gov (United States)

Mishkin, Kathryn; Alaei, Kamiar; Alikeyeva, Elmira; Paynter, Christopher; Aringazina, Altyn; Alaei, Arash

2018-02-26

TB drug resistance poses a serious threat to the public health of Kazakhstan. This paper presents findings related to TB treatment outcome and drug resistant status among people coinfected with HIV and TB in Kazakhstan. Cohort study using data were provided by the Kazakhstan Ministry of Health's National Tuberculosis Program for 2014 and 2015. Chi-square and logistical regression were performed to understand factors associated with drug resistant TB status and TB treatment outcome. In bivariate analysis, drug resistant status was significantly associated with year of TB diagnosis (p=0.001) viral load (p=0.03). TB treatment outcome was significantly associated with age at diagnosis (p=01), ARV treatment (p <0.0001), and TB drug resistant status (p=0.02). In adjusted analysis, drug resistance was associated with increased odds of successful completion of treatment with successful result compared to treatment failure (OR 6.94, 95% CI: 1.39-34.44) CONCLUSIONS: Our results suggest that being drug resistant is associated with higher odds of completing treatment with successful outcome, even when controlling for receipt of ARV therapy. Copyright © 2018. Published by Elsevier Ltd.

Measurement of 167Er(n,p)167Ho reaction at 13.5 and 14.8 MeV

International Nuclear Information System (INIS)

Luo, Junhua; Liu, Jun; Han, Jiuning; Jiang, Li; Liu, Rong; Ge, Suhong; Liu, Zhenlai

2013-01-01

We have measured the 167 Er(n,p) 167 Ho cross-sections at two different neutron energies 13.5 and 14.8 MeV. Measurements were performed at Pd-300 neutron generator of Chinese Academy of Engineering Physics (CAEP) with monoenergetic neutrons produced via the 3 H(d,n) 4 He reaction using a tritium–titanium (T–Ti) target. Induced gamma activities were measured by a high-resolution gamma-ray spectrometer with high-purity germanium (HPGe) detector. The data for 167 Er(n,p) 167 Ho reaction cross-sections are reported to be 2.2±0.6 and 2.8±1.4 mb at 13.5±0.2 and 14.8±0.2 MeV incident neutron energies, respectively. The cross sections were also estimated with the TALYS-1.4 nuclear model code and compared with experimental data found in the literature, and with the comprehensive evaluation data in ENDF/B-VII.1 and JEFF-3.1/A libraries. - Highlights: • D–T neutron source was used to measure cross sections using activation method. • 27 Al(n,α) 24 Na was used as the monitor for the measurement. • The cross sections for the 167 Er(n,p) 167 Ho reactions have been measured. • Contribution of the interfering reaction 170 Er(n,α) 167 Dy was subtracted. • The results were compared with previous data and with evaluation data

Properties of alginate fiber spun-dyed with fluorescent pigment dispersion.

Science.gov (United States)

Wang, Ping; Tawiah, Benjamin; Tian, Anli; Wang, Chunxia; Zhang, Liping; Fu, Shaohai

2015-03-15

Spun-dyed alginate fiber was prepared by the spun-dyeing method with the mixture of fluorescent pigment dispersion and sodium alginate fiber spinning solution, and its properties were characterized by SEM, TGA, DSC, and XRD. The results indicate that fluorescent pigment dispersion prepared with esterified poly (styrene-alt maleic acid) had excellent compatibility with sodium alginate fiber spinning solution, and small amount of fluorescent pigment could reduce the viscosity of spun-dyed spinning solutions. SEM photo of spun-dyed alginate fiber indicated that fewer pigment particles deposited on its surface. TGA, DSC, and XRD results suggested that thermal properties and crystal phase of spun-dyed alginate fibers had slight changes compared to the original alginate fibers. The fluorescence intensity of spun-dyed alginate fiber reached its maximum when the content of fluorescent pigment was 4%. The spun-dyed alginate fiber showed excellent rubbing and washing fastness. Copyright © 2014 Elsevier Ltd. All rights reserved.

Electrical and magnetic transport properties of DyTiGe

International Nuclear Information System (INIS)

Dagula, W.; Tegus, O.; Li, X.W.; Zhang, L.; Brueck, E.; Boer, F.R. de; Buschow, K.H.J.

2004-01-01

Electrical resistivity and magnetoresistance of DyTiGe were investigated as a function of temperature and magnetic field. DyTiGe is an antiferromagnet with Neel temperature, T N , of 180 K. The electrical resistivity has an anomaly around T N . Below T N , the magnetoresistance of DyTiGe abruptly changes at a critical field. At 5 K, we observe a magnetoresistance reduction of about 20%

Effect of ligand substitution on the SMM properties of three isostructural families of double-cubane Mn4Ln2 coordination clusters.

Science.gov (United States)

Akhtar, Muhammad Nadeem; Lan, Yanhua; AlDamen, Murad A; Zheng, Yan-Zhen; Anson, Christopher E; Powell, Annie K

2018-03-06

Three isostructural lanthanide series with a core of MnMnLn 2 are reported. These three families have the formulae of [MnMnLn 2 (μ 4 -O) 2 (H 2 edte) 2 (piv) 6 (NO 3 ) 2 ] {no crystallization solvent, Ln = La, Ce, Pr, Nd, Eu (1-4, 6); solv = 3MeCN, Ln = Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Y (5, 7-13)}, where H 2 edte = N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine and piv = pivalate; [MnMnLn 2 (μ 4 -O) 2 (H 2 edte) 2 (benz) 6 (NO 3 ) 2 ], where benz = benzoate, or [MnMnLn 2 (μ 4 -O) 2 (edteH 2 ) 2 (benz) 6 (NO 3 ) 2 ]·2MeCN {Ln = Gd, Tb, Dy (14-16); and [MnMnLn 2 (μ 4 -O) 2 (edteH 2 ) 2 (piv) 8 ].solv {solv = 4MeCN, Ln = La (17); solv = 2MeCN·tol·H 2 O, Ln = Pr, Nd, Sm, Tb (18-20, 22); solv = 2MeCN·H 2 O, Ln = Gd (21). These compounds crystallize in two different systems, namely, monoclinic in the space groups P2 1 /n for 1-4, 6, and 14-16 and C2/c for 5, 7-13, 18-20, and 22 and triclinic in the space group P1[combining macron] for 17 and 21. The crystal structures of these compounds display a face-fused dicubane structure connected by different types of bridged oxygen atoms. Solid-state dc magnetic susceptibility characterization was carried out for 1-22, and fitting showed that Mn III Mn III is antiferromagnetically (AF) coupled and Mn II Mn III , Mn II Ln and Mn III Ln are weakly ferromagnetically coupled. In addition, ac measurements were carried out and showed that only 7, 15, and 22 for Tb, 8 and 16 for Dy, and 20 for Sm exhibited slow magnetization relaxation. In the case of 15, it was possible to determine the energy barrier of the slow-relaxation behavior by fitting peak temperatures to the Arrhenius law, which gave a value of U eff = 21.2 K and a pre-exponential factor of τ 0 = 4.0 × 10 -9 s.

LiHo(PO34

Directory of Open Access Journals (Sweden)

Mokhtar Férid

2009-02-01

Full Text Available Lithium holmium(III polyphosphate(V, LiHo(PO34, belongs to the type I of polyphosphates with general formula ALn(PO34, where A is a monovalent cation and Ln is a trivalent rare earth cation. In the crystal structure, the polyphosphate chains spread along the b-axis direction, with a repeat period of four tetrahedra and 21 internal symmetry. The Li and Ho atoms are both located on twofold rotation axes and are surrounded by four and eight O atoms, leading to a distorted tetrahedral and dodecahedral coordination, respectively. The HoO8 polyhedra are isolated from each other, the closest Ho...Ho distance being 5.570 (1 Å.

Unexpected structure in the E2 quasicontinuum spectrum of 154Dy

International Nuclear Information System (INIS)

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

1988-01-01

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

Synthesis, structure, and physical properties of new rare earth ferrocenoylacetonates.

Science.gov (United States)

Koroteev, Pavel S; Dobrokhotova, Zhanna V; Ilyukhin, Andrey B; Efimov, Nikolay N; Rouzières, Mathieu; Kiskin, Mikhail A; Clérac, Rodolphe; Novotortsev, Vladimir M

2016-04-21

New ferrocenoylacetonate complexes of several rare earth elements, [Ln(fca)3(bpy)]·MeC6H5 (Ln = Pr (), Eu (), Gd (), Tb (), Dy (), Ho (), Y (); bpy - 2,2'-bipyridine; Hfca - FcCOCH2COMe) as well as scandium ferrocenoylacetonate [Sc(fca)3]·0.5MeC6H5 (), were synthesized and characterized by single crystal X-ray diffraction analysis. In the crystal lattice of the isostructural complexes , two [Ln(fca)3(bpy)] molecules form a pair due to stacking interactions between the bpy ligands. The Ln(3+) ions are coordinated in a square antiprism geometry with a coordination number of 8. The Sc(3+) ions in complex are coordinated in an octahedral geometry. Thermolysis of complexes was studied under air and argon atmospheres; in the first case, it affords perovskites LnFeO3 as one of the products. Complexes display single-molecule magnet properties, and the effective relaxation barrier for the Dy complex , was found to be Δeff/kB = 241 K, which is one of the highest values obtained for a mononuclear β-diketonate lanthanide complex.

Emission spectra of phosphor MgSO4 doped with Dy and Mn

International Nuclear Information System (INIS)

Zhang Chunxiang; Chen Lixin; Tang Qiang; Luo Daling; Qiu Zhiren

2001-01-01

Emission spectra of phosphor MgSO 4 doped with Dy and Dy/Mn were measured with an optical multichannel analyzer and a linear heating system whose temperature was controlled by a microcomputer. The emission spectrum bands at 480 nm and 580 nm of phosphor MgSO 4 doped with Dy were observed in the three dimensional (3D) glow curves. Compared with the 3D spectrum of CaSO 4 :Dy and the spectrum bands of MgSO 4 :Dy shows the same wavelengths which resulted from the quantum transitions among the energy levels of Dy 3 '+ ions. The intensities of the glow peaks in both spectrum bands (480 nm and 580 nm) of phosphor MgSO 4 doped with Dy/Mn were dramatically reduced except the 380 degree C glow peak

From a Dy(III) single molecule magnet (SMM) to a ferromagnetic [Mn(II)Dy(III)Mn(II)] trinuclear complex.

Science.gov (United States)

Bhunia, Asamanjoy; Gamer, Michael T; Ungur, Liviu; Chibotaru, Liviu F; Powell, Annie K; Lan, Yanhua; Roesky, Peter W; Menges, Fabian; Riehn, Christoph; Niedner-Schatteburg, Gereon

2012-09-17

The Schiff base compound 2,2'-{[(2-aminoethyl)imino]bis[2,1-ethanediyl-nitriloethylidyne]}bis-2-hydroxy-benzoic acid (H(4)L) as a proligand was prepared in situ. This proligand has three potential coordination pockets which make it possible to accommodate from one to three metal ions allowing for the possible formation of mono-, di-, and trinuclear complexes. Reaction of in situ prepared H(4)L with Dy(NO(3))(3)·5H(2)O resulted in the formation of a mononuclear complex [Dy(H(3)L)(2)](NO(3))·(EtOH)·8(H(2)O) (1), which shows SMM behavior. In contrast, reaction of in situ prepared H(4)L with Mn(ClO(4))(2)·6H(2)O and Dy(NO(3))(3)·5H(2)O in the presence of a base resulted in a trinuclear mixed 3d-4f complex (NHEt(3))(2)[Dy{Mn(L)}(2)](ClO(4))·2(H(2)O) (2). At low temperatures, compound 2 is a weak ferromagnet. Thus, the SMM behavior of compound 1 can be switched off by incorporating two Mn(II) ions in close proximity either side of the Dy(III). This quenching behavior is ascribed to the presence of the weak ferromagnetic interactions between the Mn(II) and Dy(III) ions, which at T > 2 K act as a fluctuating field causing the reversal of magnetization on the dysprosium ion. Mass spectrometric ion signals related to compounds 1 and 2 were both detected in positive and negative ion modes via electrospray ionization mass spectrometry. Hydrogen/deuterium exchange (HDX) reactions with ND(3) were performed in a FT-ICR Penning-trap mass spectrometer.

Study of the structure of the transition nuclei 152Dy, 154Dy and 156Er at high angular momentum

International Nuclear Information System (INIS)

Azgui, F.

1985-01-01

Measurements of feeding times of high spin yrast states in 152 Dy, 154 Dy and 156 Er were utilized to obtain information about possible spin dependent shape changes. Feeding times as well as lifetimes were determined with the recoil distance technique. In 152 Dy only long feeding times (> 10 ps) could be identified, indicating that the aligned-particle yrast states are fed through configuration of similar character, with little direct population from collective cascade in the continuum region. In 154 Dy discrete states with I ≤ 30 have lifetimes which are characteristically collective, whereas the preyrast cascade exhibit both fast ( 10 ps) feeding components. The latter imply a change with increasing spin from collective to aligned-particle character, signalling a prolate to oblate shape transition. In 156 Er the yrast states up to spin 20 ℎ were found to be collective. These levels are fed, however, from long-lived high spin states, causing time delay up to ∼ 100 ps, the existence of which is interpreted as a signature for an oblate shape at high spin [fr

Determination of lanthanides in fossil samples using laser induced breakdown spectroscopy

International Nuclear Information System (INIS)

Anzano, J.M.; Lasheras, R.J.; Canudo, I.; Laguna, M.

2017-01-01

As being a fast, simple and relatively non-destructive analytical technique Laser-induced breakdown spectroscopy (LIBS) has a large variety of applications including the analysis of paleontological samples. In this work LIBS is employed for the quantitative determination of lanthanides (Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Sm, Tb, Tm and Yb) in vertebrate fossil samples comprising teeth, disarticulated complete or fragmented bones, eggshell fragments, and coprolites of dinosaurs, mammals and crocodiles. For emission line data, standard AnalaR grade salts of lanthanides were used. The major components: iron, calcium, magnesium, silicon and aluminum in the samples were also determined. The analytical information may be helpful in studying the samples for their age, formation environment and other paleontological properties. (author)

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

Studies on mixed ligand complexes of adenine and xanthine with some rare earth ions

International Nuclear Information System (INIS)

Rastogi, P.R.; Singh, Mamta; Nayan, Ram

1993-01-01

Interactions of 6-aminopurine (adenine, HA) and 2,6-dihydroxypurine (xanthine, HB) with trivalent rare earth ions Y, Tb, Dy, Ho, Er and Tm, have been studied by pH-titration methods in aqueous solution at 20 o (μ = 0.1 M KNO 3 ). The ligands in their mixtures with tripositive rare earth ions (M 3+ ) form a number of mixed ligand complexes, M 3+ -adenine-xanthine, M 3+ -(adenine) 2 -xanthine, M 3+ -adenine-(xanthine) 2 in addition to the binary complexes, M 3+ -(adenine), M 3+ -(adenine) 2 , M 3+ -(adenine) 3 , M 3+ -(xanthine), M 3+ -(xanthine) 2 and M 3+ -(xanthine) 3 . The stability constants of these complexes have been evaluated and the results discussed. (author). 13 refs., 1 fig., 1 tab

Isopiestic determination of the activity coefficients of some aqueous rare earth electrolyte solutions at 250C. I. The rare earth chlorides

International Nuclear Information System (INIS)

Spedding, F.H.; Weber, H.O.; Saeger, V.W.; Petheram, H.H.; Rard, J.A.; Habenschuss, A.

1976-01-01

The osmotic coefficients of the aqueous trichlorides of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y were determined from 0.1 M to saturation at 25 0 C. Semiempirical least-squares equations were obtained for the osmotic coefficients as a function of molality and these equations were used to calculate water activities and mean molal activity coefficients. The water activities of the light rare earth chlorides at constant molalities are higher than for the heavy rare earths, while the mean molal activity coefficients are larger for the heavy rare earths than for the light ones. The above effects are discussed in terms of changes in the cationic radii and hydration of the rare earth ions

An XRF method for determination of common rare earth impurities in high purity yttrium oxide

International Nuclear Information System (INIS)

Dixit, R.M.; Deshpande, S.S.

1975-01-01

An XRF method for the estimation of Eu, Gd, Tb, Dy, Ho, Er and Yb in yttrium oxide has been developed. Samples are converted to yttrium oxalate and presented to the spectrometer in the form of pressed pellets. Philips PW-1220, a semi-automatic x-ray spectrometer, is used for the analysis. Line interference problems are studied for selecting analysis lines. For the elements except that of Yb, the lower estimation limit is 0.005% and for Yb, it is 0.01%. The average standard deviation is approximately 5% for various elements in the concentration range of 0.005% to 1.0%. The method has been tested for its accuracy by analysing synthesized samples with known composition at three different concentrations. (author)

Magnetostriction anisotropy in the rare earth RCo5 compounds on spontaneous spin-orientation phase transitions

International Nuclear Information System (INIS)

Ahdreev, A.V.; Deryagin, A.V.; Zadvorkin, S.M.

1983-01-01

The temperature dependences of parameters a and c in the crystal lattice of RCo 5 compounds (R=Pr, Tb, Dy, Ho) are studied in an X-ray diffractometer the spin reorientation region. On the basis of these data the magnetostriction constants lambdasub(1)sup(α, 2) and lambdasub(2)sup(α, 2) are determined for temperatures corresponding to the middle of reorientation regions of the compounds mentioned above (excluding PrCo 5 ). The values of lambdasub(1)sup(α, 2) and lambdasub(2)sup(α, 2) at T=0 K are calculated on the basis of the single-ion model for all the compounds investigalted and also for some other intermetallides of the RCo 5 type in which spontaneous spin reorien tation transitions do not occur

Easy and General Synthesis of Large-Sized Mesoporous Rare-Earth Oxide Thin Films by 'Micelle Assembly'.

Science.gov (United States)

Li, Yunqi; Bastakoti, Bishnu Prasad; Imura, Masataka; Dai, Pengcheng; Yamauchi, Yusuke

2015-12-01

Large-sized (ca. 40 nm) mesoporous Er2O3 thin films are synthesized by using a triblock copolymer poly(styrene-b-2-vinyl pyridine-b-ethylene oxide) (PS-b-P2VP-b-PEO) as a pore directing agent. Each block makes different contributions and the molar ratio of PVP/Er(3+) is crucial to guide the resultant mesoporous structure. An easy and general method is proposed and used to prepare a series of mesoporous rare-earth oxide (Sm2O3, Dy2O3, Tb2O3, Ho2O3, Yb2O3, and Lu2O3) thin films with potential uses in electronics and optical devices. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Modification of magnetoresistance and magnetic properties of Ni thin films by adding Dy interlayer

Science.gov (United States)

Vorobiov, S. I.; Shabelnyk, T. M.; Shutylieva, O. V.; Pazukha, I. M.; Chornous, A. M.

2018-03-01

The paper reports the influence of dysprosium (Dy) interlayer addition on structure, magnetoresistance and magnetic properties of nickel (Ni) thin films. Trilayer film systems Ni/Dy/Ni have been prepared by alternate electron-beam evaporation. It is demonstrated that all as-prepared and annealed Ni thin films have face-centered cubic structure. The composition of the samples after addition of the Dy interlayer corresponds to the combination of face-centered cubic (Ni) and hexagonal close-packed (Dy) structures. The structure of Ni/Dy/Ni film systems changes from amorphous to polycrystalline when Dy interlayer thickness (t Dy) is more than 15 nm. The value of magnetoresistance increases with the adding the Dy interlayer in both longitudinal and transverse geometries, meanwhile the anisotropic character of magnetoresistance field dependences retained. The saturation and reversal magnetizations are reduced with the increasing of the Dy thickness interlayer, while the coercivity takes the minimum value at t Dy = 15 nm. The following increasing of t Dy leads to increasing of coercivity near to three times. This result indicates the influence of the crystal structure on the magnetic properties of Ni thin films at adding Dy interlayer.

Study of a new dosimetric radio-thermoluminescent systems

International Nuclear Information System (INIS)

Cazac, T.C.

1980-01-01

This is the first Romanian study to investigate conditions to obtain the radio-thermo-luminescent systems: MgB 4 O 7 :A(A-Nd,Sm,Eu,Dy,Tb,Dy+Sm and Tb+Sm) MgF 2 A (A=Mn,Dy,Tb,Sm,Li), their essential dosimetric characters, as well as the (MgF 2 =Mn) thermophosphorus mixture with a ( 6 LiF) lithium target. An investigation was developed upon a new category of radio-thermoluminescent detectors with low radiation energy dependence and fading, magnesjum boride activated by several elements of the lanthanides class (Nd,Sm,Eu,Dy,Tb). A new radio-thermoluminescent dosimetric system with high sensitivity and moderate dependence on energy radiation - (Mnsup(2+)) manganese activated magnesium fluoride - was also studied. The author explored application of investigated detectors MgF 2 =Mn, MgB 4 O 7 =Dy and MgB 4 O 7 :Tb in neutron dosimetry in complex gamma-neutron fields. It is deemed that by using the dosimetric systems reported in the thesis in order to measure gamma, beta and neutron radiation doses, dosimetric control can be ensured both in professional dosimetry and in nuclear accident dosimetry, as well as in various basic and applicative investigations. A modest contribution is thus made towards achieving the national nuclear program through an extension of the thermophosphorus range with practical applications in nuclear radiation dosimetry. (author)

Improving the SMM and luminescence properties of lanthanide complexes with LnO9 cores in the presence of ZnII: an emissive Zn2Dy single ion magnet.

Science.gov (United States)

Fondo, Matilde; Corredoira-Vázquez, Julio; Herrera-Lanzós, Antía; García-Deibe, Ana M; Sanmartín-Matalobos, Jesús; Herrera, Juan Manuel; Colacio, Enrique; Nuñez, Cristina

2017-12-12

Mononuclear complexes of stoichiometry [Ln(H 3 L)(H 2 O)(NO 3 )](NO 3 ) 2 (Ln = Tb, 1; Dy, 2, Er, 3), which crystallise with different solvates, and the heterotrinuclear compound [Zn 2 Dy(L)(NO 3 ) 3 (OH)] (4) can be obtained with the same H 3 L compartmental ligand. The single X-ray crystal structure of the mononuclear complexes shows a LnO 9 core with a muffin-like disposition while the geometry of the DyO 9 core in 4 seems to be closer to spherical capped square antiprism. The analysis of the magnetic properties of all the complexes demonstrates that the mononuclear lanthanide compounds do not show slow relaxation of the magnetization, even when the samples are diluted with a diamagnetic matrix and subjected to a dc applied field of 1000 Oe. Nevertheless, the heterotrinuclear dysprosium complex 4·3H 2 O is a field-induced single ion magnet, with an estimated U eff barrier of 59 K. The luminescence characterisation of all the metal complexes in methanol solution at 298 K also shows a notable increase in the fluorescence emission of the heterotrinuclear complex with respect to the mononuclear ones, in such a way that 4 can be defined as a fluorescent single ion magnet.

High-spin structure of neutron-rich Dy isotopes

Indian Academy of Sciences (India)

Neutron-rich Dy isotopes; high-spin states; g-factors; cranked HFB theory. ... for 164Dy marking a clear separation in the behaviour as a function of neutron ... cipal x-axis as the cranking axis) in this mass region we have planned to make a sys-.

Utility of Lithium in Rare-Earth Metal Reduction Reactions to Form Nontraditional Ln2+ Complexes and Unusual [Li(2.2.2-cryptand)]1+ Cations.

Science.gov (United States)

Huh, Daniel N; Darago, Lucy E; Ziller, Joseph W; Evans, William J

2018-02-19

The utility of lithium compared to other alkali metals in generating Ln 2+ rare-earth metal complexes via reduction of Ln 3+ precursors in reactions abbreviated as LnA 3 /M (Ln = rare-earth metal; A = anionic ligand; M = alkali metal) is described. Lithium reduction of Cp' 3 Ln (Cp' = C 5 H 4 SiMe 3 ; Ln = Y, Tb, Dy, Ho) under Ar in the presence of 2.2.2-cryptand (crypt) forms new examples of crystallographically characterizable Ln 2+ complexes of these metals, [Li(crypt)][Cp' 3 Ln]. In each complex, lithium is found in an N 2 O 4 donor atom coordination geometry that is unusual for the cryptand ligand. Magnetic susceptibility data on these new examples of nontraditional divalent lanthanide complexes are consistent with 4f n 5d 1 electronic configurations. The Dy and Ho complexes have exceptionally high single-ion magnetic moments, 11.35 and 11.67 μ B , respectively. Lithium reduction of Cp' 3 Y under N 2 at -35 °C forms the Y 2+ complex (Cp' 3 Y) 1- , which reduces dinitrogen upon warming to room temperature to generate the (N 2 ) 2- complex [Cp' 2 Y(THF)] 2 (μ-η 2 :η 2 -N 2 ). These results provide insight on the factors that lead to reduced dinitrogen complexes and/or stable divalent lanthanide complexes as a function of the specific reducing agent and conditions.

Sledování vlivu kvasinek na chemické a senzorické vlastnosti vyráběného vína

OpenAIRE

Petrášová, Ludmila

2016-01-01

Tato diplomová práce se zabývá sledováním vlivu kvasinek na chemické a senzorické vlastnosti vyráběného vína. Cílem experimentální části bylo pomocí metody SPME-GC-MS identifikovat aromaticky aktivní látky v kvasícím moštu a víně odrůdy Hibernal a ve víně Rulandské bílé. U obou odrůd byla při výrobě využita autochtonní kvasinka izolovaná v naší laboratoři z povrchu bobulí odrůdy Hibernal. Bylo zjištěno, že obě vyráběná vína mají při použití naší kvasinky podobný aromatický profil. K dalším cí...

Mechanical and corrosion properties of binary Mg–Dy alloys for medical applications

International Nuclear Information System (INIS)

Yang Lei; Huang Yuanding; Peng Qiuming; Feyerabend, Frank; Kainer, Karl Ulrich; Willumeit, Regine; Hort, Norbert

2011-01-01

Microstructure, mechanical and corrosion properties of binary magnesium–dysprosium (Mg-5, 10, 15, 20 wt.% Dy) alloys were investigated for medical applications. In the as-cast condition, the distribution of Dy is quite inhomogeneous. Mg–10Dy alloy exhibits a moderate tensile and compression yield strength, and the best elongation and corrosion resistance. After T4 (solutionizing) treatment, the distribution of Dy becomes homogeneous. The tensile and compression yield strength of all Mg–Dy alloys decreases. The elongation remains unchanged, while the corrosion resistance is largely improved after T4 treatment.

Mechanical and corrosion properties of binary Mg-Dy alloys for medical applications

Energy Technology Data Exchange (ETDEWEB)

Yang Lei, E-mail: lei.yang@hzg.de [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Max-Planck-Str. 1, D-21502 Geesthacht (Germany); Yuanding, Huang; Qiuming, Peng; Feyerabend, Frank; Kainer, Karl Ulrich; Willumeit, Regine; Hort, Norbert [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Max-Planck-Str. 1, D-21502 Geesthacht (Germany)

2011-12-15

Microstructure, mechanical and corrosion properties of binary magnesium-dysprosium (Mg-5, 10, 15, 20 wt.% Dy) alloys were investigated for medical applications. In the as-cast condition, the distribution of Dy is quite inhomogeneous. Mg-10Dy alloy exhibits a moderate tensile and compression yield strength, and the best elongation and corrosion resistance. After T4 (solutionizing) treatment, the distribution of Dy becomes homogeneous. The tensile and compression yield strength of all Mg-Dy alloys decreases. The elongation remains unchanged, while the corrosion resistance is largely improved after T4 treatment.

Energy levels of Ho3+ in HoCl63-

International Nuclear Information System (INIS)

Tanner, P.A.

1987-01-01

The 5 S 2 , 5 F 4 , 5 F 2 , 3 K 8 , 5 G 6 , 5 F 1 , 5 G 5 5 I 8 absorption spectra of Cs 2 NaHoCl 6 have been recorded at temperatures down to that of liquid helium and new assignments are made for the 5 S 2 , 5 F 4 , 3 K 8 and 5 G 5 terms of HoCl 6 3- . The 5 F 3 → 5 I 8 , 5 F 4 , 5 S 2 → 5 I 7 , 5 I 8 and 5 F 5 → 5 I 7 luminescence transitions of HoCl 6 3- in various elpasolite lattices are reported and assigned, together with luminescence decay measurements. Including the previously reported data, these results enable 57 of the first 60 crystal-field levels of HoCl 6 3- , comprising 14 Lsub(j) terms, to be firmly assigned and tentative assignments are made for the remaining three levels. The agreement between the calculated and observed crystal-field splittings is reasonable. (author)

Co-precipitation synthesis of YAG:Dy nanophosphor and its thermometric properties

International Nuclear Information System (INIS)

Chong, Joo-Yun; Zhang, Yuelan; Wagner, Brent K.; Kang, Zhitao

2013-01-01

Highlights: •YAG:Dy nanophosphors were synthesized with particle size of about 50 nm. •Optimized doping concentration of 6%Dy was determined. •Thermometric photoluminescence properties were studied between 20 and 350 °C. •Temperature-sensitive change in peak ratio of 496/457 nm emissions was demonstrated. •Suitable for potential thermographic applications when dispersed in a liquid media. -- Abstract: Dy 3+ doped yttrium aluminum garnet (YAG) nanophosphors were synthesized by a co-precipitation method for potential thermographic applications in a liquid media dispersed with fluorescent nanoparticles. The doping concentration and annealing temperature on the structural and optical properties of YAG:Dy were investigated. Pure phase YAG:Dy nanophosphors were obtained by annealing the co-precipitated hydroxide products at above 900 °C. Maximum photoluminescence intensity was observed from 6%Dy doped YAG samples. The effect of measuring temperature between 20 and 350 °C on the photoluminescence spectra of nano YAG:Dy was investigated. A temperature-sensitive change in the peak intensity ratio of 496/457 nm emission lines was demonstrated for such nanophosphors for the first time, suggesting potential applications in temperature monitoring of fuel spray

Co-precipitation synthesis of YAG:Dy nanophosphor and its thermometric properties

Energy Technology Data Exchange (ETDEWEB)

Chong, Joo-Yun [School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Zhang, Yuelan [School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Wagner, Brent K. [Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Kang, Zhitao, E-mail: zhitao.kang@gtri.gatech.edu [Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, GA 30332 (United States); School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

2013-12-25

Highlights: •YAG:Dy nanophosphors were synthesized with particle size of about 50 nm. •Optimized doping concentration of 6%Dy was determined. •Thermometric photoluminescence properties were studied between 20 and 350 °C. •Temperature-sensitive change in peak ratio of 496/457 nm emissions was demonstrated. •Suitable for potential thermographic applications when dispersed in a liquid media. -- Abstract: Dy{sup 3+} doped yttrium aluminum garnet (YAG) nanophosphors were synthesized by a co-precipitation method for potential thermographic applications in a liquid media dispersed with fluorescent nanoparticles. The doping concentration and annealing temperature on the structural and optical properties of YAG:Dy were investigated. Pure phase YAG:Dy nanophosphors were obtained by annealing the co-precipitated hydroxide products at above 900 °C. Maximum photoluminescence intensity was observed from 6%Dy doped YAG samples. The effect of measuring temperature between 20 and 350 °C on the photoluminescence spectra of nano YAG:Dy was investigated. A temperature-sensitive change in the peak intensity ratio of 496/457 nm emission lines was demonstrated for such nanophosphors for the first time, suggesting potential applications in temperature monitoring of fuel spray.

Dy:Eu doped CaBAl glasses for white light applications

Science.gov (United States)

Lodi, T. A.; Sandrini, M.; Medina, A. N.; Barboza, M. J.; Pedrochi, F.; Steimacher, A.

2018-02-01

The combination of Eu3+ and Dy3+ in co-doped glassy materials provides interesting applicability for white light emission devices. In this work, Dy:Eu doped Calcium Boroaluminate (CaBAl) glasses were prepared by conventional melting quenching, with 3 wt% of Dy2O3 and Eu2O3 content varying from 0 to 3 wt%, and results of absorption spectra, photoluminescence and photoluminescence lifetime are discussed in terms of Eu2O3 content. The photoluminescence of the samples was studied under excitation of 365 and 405 nm light source. The 365 nm excitation shows favor to the Dy3+ ion emission. The results of photoluminescence lifetime at 575 nm (Dy3+) shows a decrease due to Eu2O3 addition, which suggests an energy transfer from Dy3+ (donor) to the Eu3+ (acceptor). On the other hand, under excitation of 405 nm, the photoluminescence lifetime at 575 nm (Dy3+) shows no significant changes due to Eu2O3 amount, which indicates that the energy transfer from Dy3+ to Eu3+ (under λexc = 405 nm) is negligible. However, the results of photoluminescence under 405 nm excitation present a white yellowish emission in the CIE diagram, which shifts to red with Eu2O3 addition. The combination of a Blue LED (BL) emission with the emission of the samples was also studied in the CIE diagram, in order to improve light emission and to obtain ideal White Light (WL). The results show that by modifying the emission intensity of BL, it is possible to achieve a route for smart lighting, close to the circadian light cycle.

Effect of Dy additions on microstructure and magnetic properties of Fe-Nd-B magnets

International Nuclear Information System (INIS)

Ramesh, R.; Thomas, G.; Ma, B.M.

1987-05-01

It is shown that increasing additions of Dy causes the remanence B/sub r/ to decrease linearly. The intrinsic coercivity, iHc, increases sharply for small additions of Dy, but the increase is not proportional for higher Dy contents. The iHc increases almost linearly with the effective anisotropy field of the RE 2 Fe 14 B phase until the Dy content is about 10% of the total rare earth content. Above this concentration, there is strong deviation from linearity. Various types of possible concentration profiles of the substituted rare earth are suggested. It is also argued that preferential segregation of Dy to the interfaces could be beneficial in increasing the nucleation field. Morphologically there is no apparent effect of Dy on the microstructure. However, in the 5 atomic % Dy sample, Dy rich oxides were observed. It is shown through Energy Dispersive Xray Spectroscopy (EDXS) line profiling that Dy partitions preferentially into the RE 2 Fe 14 B phase in all the cases. No segregation of Dy to the interphase interfaces has been detected

Rare-earth doped gadolinia based phosphors for potential multicolor and white light emitting deep UV LEDs.

Science.gov (United States)

Bedekar, Vinila; Dutta, Dimple P; Mohapatra, M; Godbole, S V; Ghildiyal, R; Tyagi, A K

2009-03-25

Gadolinium oxide host and europium/dysprosium/terbium doped gadolinium oxide nanoparticles were synthesized using the sonochemical technique. Gadolinium oxide nanocrystals were also co-doped with total 2 mol% of Eu(3+)/Dy(3+),Eu(3+)/Tb(3+),Dy(3+)/Tb(3+), and also Eu(3+)/Dy(3+)/Tb(3+) ions, by the same method. The nanoparticles obtained were characterized using powder x-ray diffraction (XRD), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) techniques. The size of the particles ranged from 15 to 30 nm. The triple doped samples showed multicolor emission on single wavelength excitation. The photoluminescence results were correlated with the lifetime data to get an insight into the luminescence and energy transfer processes taking place in the system. On excitation at 247 nm, the novel nanocrystalline Gd(2)O(3):RE (RE = Dy, Tb) phosphor resulted in having very impressive CIE chromaticity coordinates of x = 0.315 and y = 0.316, and a correlated color temperature of 6508 K, which is very close to standard daylight.

Návrh ubytovacího rezervačního internetového portálu

OpenAIRE

Čurilla, Miroslav

2010-01-01

Táto diplomová práca sa zaoberá návrhom ubytovacieho rezervačného internetového portálu. Cieľom práce je navrhnutie systému rezervovania ubytovania v ubytovacích zariadenia optimálnym spôsobom. Vedľajšími cieľmi je navrhnutie hardvérových, softvérových, bezpečnostných, marketingových a ekonomických riešení pri návrhu ubytovacieho rezervačné internetového portálu. This master’s thesis deals with the design of the internet portal for the reservation of accommodation. Its objective is the pro...

A family of acetato-diphenoxo triply bridged dimetallic Zn(II)Ln(III) complexes: SMM behavior and luminescent properties.

Science.gov (United States)

Oyarzabal, Itziar; Artetxe, Beñat; Rodríguez-Diéguez, Antonio; García, JoséÁngel; Seco, José Manuel; Colacio, Enrique

2016-06-21

Eleven dimetallic Zn(II)-Ln(III) complexes of the general formula [Zn(µ-L)(µ-OAc)Ln(NO3)2]·CH3CN (Ln(III) = Pr (1), Nd (2), Sm (3), Eu (4), Gd (5), Tb (6), Dy (7), Ho (8), Er (9), Tm (10), Yb (11)) have been prepared in a one-pot reaction from the compartmental ligand N,N'-dimethyl-N,N'-bis(2-hydroxy-3-formyl-5-bromo-benzyl)ethylenediamine (H2L). In all these complexes, the Zn(II) ions occupy the internal N2O2 site whereas the Ln(III) ions show preference for the O4 external site. Both metallic ions are bridged by an acetate bridge, giving rise to triple mixed diphenoxido/acetate bridged Zn(II)Ln(III) compounds. The Nd, Dy, Er and Yb complexes exhibit field induced single-ion magnet (SIM) behaviour, with Ueff values ranging from 14.12 to 41.55 K. The Er complex shows two relaxation processes, but only the second relaxation process with an energy barrier of 21.0 K has been characterized. The chromophoric L(2-) ligand is able to act as an "antenna" group, sensitizing the near-infrared (NIR) Nd(III) and Yb(III)-based luminescence in complexes 2 and 11 and therefore, both compounds can be considered as magneto-luminescent materials. In addition, the Sm(III), Eu(III) and Tb(III) derivatives exhibit characteristic emissions in the visible region.

DyNi2Mn—magnetisation and Mössbauer spectroscopy

International Nuclear Information System (INIS)

Wang Jianli; Campbell, Stewart James; Kennedy, Shane Joseph; Dou Shixue; Wu Guangheng

2012-01-01

The physical properties of DyNi 2 Mn doped with 57 Fe have been investigated by X-ray diffraction, magnetisation (10–300 K) and 57 Fe Mössbauer spectroscopy measurements (5–300 K). DyNi 2 Mn( 57 Fe) crystallizes in the MgCu 2 -type cubic structure (Fd   −3m space group). The ordering temperature is found to be T C  = 99(2) K, much higher than those of DyNi 2 (∼22 K) and DyMn 2 (∼35 K). Analyses of isothermal M–H curves and the related Arrott plots confirm that the magnetic phase transition at T C is second order. The magnetic entropy change around T C is 4.0 J/kg K for a magnetic field change of 0 T to 5 T. The spectra above T C exhibit features consistent with quadrupolar effects while below T C the spectra exhibit magnetic hyperfine splitting. The Debye temperature for DyNi 2 Mn has been determined as θ D  = 200(20) K from a fit to the variable temperature isomer shift IS(T).

DyNi{sub 2}Mn-magnetisation and Moessbauer spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Wang Jianli; Campbell, Stewart James, E-mail: stewart.campbell@adfa.edu.au [University of New South Wales, School of Physical, Environmental and Mathematical Sciences (Australia); Kennedy, Shane Joseph [ANSTO, Bragg Institute (Australia); Dou Shixue [University of Wollongong, Institute for Superconductivity and Electronic Materials (Australia); Wu Guangheng [Chinese Academy of Science, Institute of Physics (China)

2012-03-15

The physical properties of DyNi{sub 2}Mn doped with {sup 57}Fe have been investigated by X-ray diffraction, magnetisation (10-300 K) and {sup 57}Fe Moessbauer spectroscopy measurements (5-300 K). DyNi{sub 2}Mn({sup 57}Fe) crystallizes in the MgCu{sub 2}-type cubic structure (Fd{sup }-3m space group). The ordering temperature is found to be T{sub C} = 99(2) K, much higher than those of DyNi{sub 2} ({approx}22 K) and DyMn{sub 2} ({approx}35 K). Analyses of isothermal M-H curves and the related Arrott plots confirm that the magnetic phase transition at T{sub C} is second order. The magnetic entropy change around T{sub C} is 4.0 J/kg K for a magnetic field change of 0 T to 5 T. The spectra above T{sub C} exhibit features consistent with quadrupolar effects while below T{sub C} the spectra exhibit magnetic hyperfine splitting. The Debye temperature for DyNi{sub 2}Mn has been determined as {theta}{sub D} = 200(20) K from a fit to the variable temperature isomer shift IS(T).

Neutron detection using Dy2O3 activation detectors

International Nuclear Information System (INIS)

Gomaa, M.A.; Mohamed, E.J.

1979-01-01

The aim of the present study is to examine the usefulness of Dy 2 O 3 not only as thermal neutron activation detector but also as a fast neutron detector. For thermal neutrons, the half life of 165 Dy is measured to be (141 +- 6) min, its response to thermal neutrons is (2.18 +- 0.01) cpm/ncm -2 s -1 for a 250 mg Dy 2 O 3 pellet. For fast neutrons the Dy 2 O 3 detector is placed within a 20 cm polyethylene sphere and its response is found to be (2.2 +- 0.1) cpm/ncm -2 s -1 for 4 MeV neutrons and (2.10 +- 0.04) cpm/ncm -2 s -1 for 14 MeV neutrons. For neutron dosimetry, its response is found to be (16.7 +- 0.4) cpm per mrem h -1 . (author)

Tuberculosis Facts - Exposure to TB

Science.gov (United States)

Tuberculosis (TB) Facts Exposure to TB What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination

Tuberculosis Facts - Testing for TB

Science.gov (United States)

Tuberculosis (TB) Facts Testing for TB What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination

Surface activation of dyed fabric for cellulase treatment.

Science.gov (United States)

Schimper, Christian B; Ibanescu, Constanta; Bechtold, Thomas

2011-10-01

Surface activation of fabric made from cellulose fibres, such as viscose, lyocell, modal fibres and cotton, can be achieved by printing of a concentrated NaOH-containing paste. From the concentration of reducing sugars formed in solution, an increase in intensity of the cellulase hydrolysis by a factor of six to eight was observed, which was mainly concentrated at the activated parts of the fabric surface. This method of local activation is of particular interest for modification of materials that have been dyed with special processes to attain an uneven distribution of dyestuff within the yarn cross-section, e.g., indigo ring-dyed denim yarn for jeans production. Fabrics made from regenerated cellulose fibres were used as model substrate to express the effects of surface activation on indigo-dyed material. Wash-down experiments on indigo-dyed denim demonstrated significant colour removal from the activated surface at low overall weight loss of 4-5%. The method is of relevance for a more eco-friendly processing of jeans in the garment industry. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Studies of normal deformation in {sup 151}Dy

Energy Technology Data Exchange (ETDEWEB)

Nisius, D.; Janssens, R.V.F.; Crowell, B. [and others

1995-08-01

The wealth of data collected in the study of superdeformation in {sup 151}Dy allowed for new information to be obtained on the normally deformed structures in this nucleus. At high spin several new yrast states have been identified for the first time. They were associated with single-particle excitations. Surprisingly, a sequence was identified with energy spacings characteristic of a rotational band of normal ({beta}2 {approximately} 0.2) deformation. The bandhead spin appears to be 15/2{sup -} and the levels extend up to a spin of 87/2{sup -}. A clear backbend is present at intermediate spins. While a similar band based on a bandhead of 6{sup +} is known in {sup 152}Dy, calculations suggest that this collective prolate band should not be seen in {sup 151}Dy. In the experiment described earlier in this report that is aimed at determining the deformations associated with the SD bands in this nucleus and {sup 152}Dy, the deformation associated with this band will be determined. This will provide further insight into the origin of this band.

Enhanced ultraviolet photo-response in Dy doped ZnO thin film

Science.gov (United States)

Kumar, Pawan; Singh, Ranveer; Pandey, Praveen C.

2018-02-01

In the present work, a Dy doped ZnO thin film deposited by the spin coating method has been studied for its potential application in a ZnO based UV detector. The investigations on the structural property and surface morphology of the thin film ensure that the prepared samples are crystalline and exhibit a hexagonal crystal structure of ZnO. A small change in crystallite size has been observed due to Dy doping in ZnO. AFM analysis ascertains the grain growth and smooth surface of the thin films. The Dy doped ZnO thin film exhibits a significant enhancement in UV region absorption as compared to the pure ZnO thin film, which suggests that Dy doped ZnO can be used as a UV detector. Under UV irradiation of wavelength 325 nm, the photocurrent value of Dy doped ZnO is 105.54 μA at 4.5 V, which is 31 times greater than that of the un-doped ZnO thin film (3.39 μA). The calculated value of responsivity is found to increase significantly due to the incorporation of Dy in the ZnO lattice. The observed higher value of photocurrent and responsivity could be attributed to the substitution of Dy in the ZnO lattice, which enhances the conductivity, electron mobility, and defects in ZnO and benefits the UV sensing property.

Mycobacterium tuberculosis Induction of Heme Oxygenase-1 Expression Is Dependent on Oxidative Stress and Reflects Treatment Outcomes

Directory of Open Access Journals (Sweden)

Neesha Rockwood

2017-05-01

Full Text Available The antioxidant enzyme heme oxygenase-1 (HO-1 is implicated in the pathogenesis of tuberculosis (TB and has been proposed as a biomarker of active disease. Nevertheless, the mechanisms by which Mycobacterium tuberculosis (Mtb induces HO-1 as well as how its expression is affected by HIV-1 coinfection and successful antitubercular therapy (ATT are poorly understood. We found that HO-1 expression is markedly increased in rabbits, mice, and non-human primates during experimental Mtb infection and gradually decreased during ATT. In addition, we examined circulating concentrations of HO-1 in a cohort of 130 HIV-1 coinfected and uninfected pulmonary TB patients undergoing ATT to investigate changes in expression of this biomarker in relation to HIV-1 status, radiological disease severity, and treatment outcome. We found that plasma levels of HO-1 were elevated in untreated HIV-1 coinfected TB patients and correlated positively with HIV-1 viral load and negatively with CD4+ T cell count. In both HIV-1 coinfected and Mtb monoinfected patients, HO-1 levels were substantially reduced during successful TB treatment but not in those who experienced treatment failure or subsequently relapsed. To further delineate the molecular mechanisms involved in induction of HO-1 by Mtb, we performed a series of in vitro experiments using mouse and human macrophages. We found that Mtb-induced HO-1 expression requires NADPH oxidase-dependent reactive oxygen species production induced by the early-secreted antigen ESAT-6, which in turn triggers nuclear translocation of the transcription factor NRF-2. These observations provide further insight into the utility of HO-1 as a biomarker of both disease and successful therapy in TB monoinfected and HIV-TB coinfected patients and reveal a previously undocumented pathway linking expression of the enzyme with oxidative stress.

Výložník kombinovaného skládkového stroje

OpenAIRE

Štursa, Martin

2013-01-01

Tato diplomová práce se zabývá konstrukcí částí kombinovaného skládkového stroje určeného pro obsluhu skládky hnědého uhlí u uhelné elektrárny. Nejprve jsou nadefinovány základní parametry stroje a silové účinky zatěžující stroj během provozu. Práce dále obsahuje návrh ocelové konstrukce kolesového výložníku, kolesa, korečků, pohonu kolesa, hřídele, ložisek a dalších částí kolesového výložníku. Tyto součásti jsou ověřeny analytickými nebo konečnoprvkovými výpočty. This master’s thesis deal...

Magnetocaloric effect in (Tb,Dy,R)(Co,Fe).sub.2./sub. (R= Ho, Er) multicomponent compounds

Czech Academy of Sciences Publication Activity Database

Tereshina, I. S.; Politova, G.A.; Tereshina, Evgeniya; Burkhanov, G.S.; Chistyakov, O.D.; Nikitin, S. A.

2011-01-01

Roč. 266, č. 1 (2011), "012077-1"-"012077-5" ISSN 1742-6588. [2nd International Symposium on Advanced Magnetic Materials and Applications (ISAMMA). Sendai, 12.07.2010-16.07.2010] Institutional research plan: CEZ:AV0Z10100520 Keywords : terfenol-D * rare-earth intermetallics * magnetostriction Subject RIV: BM - Solid Matter Physics ; Magnetism

Complexation behaviour of DADCA and DAPDA with dysprosium-166/holmium-166 parent daughter system and its potential for use in radioimmunotherapy

International Nuclear Information System (INIS)

Orsini, S.; University of Technology, Broadway, NSW; Di Bartolo, N.; Smith, S.; Baker, T.

1998-01-01

Full text: A novel approach for the delivery of therapeutic doses from 166 Ho to cancerous tissue is via the decay of its parent, 166 Dy. When designing radioimmunoconjugte, a crucial question is to determine whether the ligand used in the radiolabeling process is capable of holding the 166 Ho on decay of the parent, 166 Dy. In this study, two pendant arm macrocycles 1, 10-Diaza-4, 7, 13, 16-tetraoxacyclooctadecane-N, N'-diacetic acid, (DACDA) and 1, 10-Diaza-4, 7, 13-trioxacyclopentadecane-N, N'-diacetic acid, (DAPDA) that were reported to forms reasonably stable complexes with Dy and Ho, were synthesised. The synthesis of the two pendant arm macrocycles was first attempted using methods outlined by Chang and Rowland. The yields obtained through this method were low (10 % for both ligands) and it was considered important to investigate alternative approaches to the synthesis. The new method involved an alkylation reaction in the presence of acetonitrile and sodium bicarbonate. The method took considerably less time and the yields increased to 88 %. The ligands were characterised using 1 H NMR, 13 C NMR and mass spectrometry. The chemical and radiolytic stabilities of 166 Dy and 166 Ho complexes of the two ligands were investigated at pH = 5 and the ligands potential for use in the in vivo generator system evaluated

Sonochemical synthesis of Dy-doped ZnO nanostructures and their photocatalytic properties

Energy Technology Data Exchange (ETDEWEB)

Yayapao, Oranuch [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thongtem, Titipun, E-mail: ttpthongtem@yahoo.com [Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Phuruangrat, Anukorn, E-mail: phuruangrat@hotmail.com [Department of Materials Science and Technology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112 (Thailand); Thongtem, Somchai [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

2013-11-05

Highlights: •Undoped and Dy-doped ZnO used as photocatalysts. •They were synthesized by sonochemistry. •The promising materials for treatment of organic pollutants. -- Abstract: Dy-doped ZnO nanostructures were synthesized by a sonochemical method. The concentration effect of Dy on their phase, morphology, optical properties and photocatalytic activities was investigated. XRD patterns indicated that the as-synthesized 0–3% Dy-doped ZnO was hexagonal wurtzite structure. SEM and TEM show that the products were nanorods with their growth direction along the c axis. The photoluminescence spectrum of 3% Dy-doped ZnO, applied by Gaussian analysis, consists of three emission peaks at 376 nm, 448 nm and 487 nm. The photocatalytic activities of the as-synthesized products were determined from the degradation of methylene blue (C{sub 16}H{sub 18}N{sub 3}SCl) by UV radiation. In this research, the 3% Dy-doped ZnO showed the highest photocatalytic activity.

Sonochemical synthesis of Dy-doped ZnO nanostructures and their photocatalytic properties

International Nuclear Information System (INIS)

Yayapao, Oranuch; Thongtem, Titipun; Phuruangrat, Anukorn; Thongtem, Somchai

2013-01-01

Highlights: •Undoped and Dy-doped ZnO used as photocatalysts. •They were synthesized by sonochemistry. •The promising materials for treatment of organic pollutants. -- Abstract: Dy-doped ZnO nanostructures were synthesized by a sonochemical method. The concentration effect of Dy on their phase, morphology, optical properties and photocatalytic activities was investigated. XRD patterns indicated that the as-synthesized 0–3% Dy-doped ZnO was hexagonal wurtzite structure. SEM and TEM show that the products were nanorods with their growth direction along the c axis. The photoluminescence spectrum of 3% Dy-doped ZnO, applied by Gaussian analysis, consists of three emission peaks at 376 nm, 448 nm and 487 nm. The photocatalytic activities of the as-synthesized products were determined from the degradation of methylene blue (C 16 H 18 N 3 SCl) by UV radiation. In this research, the 3% Dy-doped ZnO showed the highest photocatalytic activity

Tuberculosis Facts - You Can Prevent TB

Science.gov (United States)

Tuberculosis (TB) Facts You Can Prevent TB What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination TB Facts: You Can Prevent TB What ...

Tuberculosis Facts - TB Can Be Treated

Science.gov (United States)

Tuberculosis (TB) Facts TB Can Be Treated What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination Page 1 of 2 TB Facts: TB ...

Search for neutrinoless double-electron capture of 156Dy

Science.gov (United States)

Finch, S. W.; Tornow, W.

2015-12-01

Background: Multiple large collaborations are currently searching for neutrinoless double-β decay, with the ultimate goal of differentiating the Majorana-Dirac nature of the neutrino. Purpose: Investigate the feasibility of resonant neutrinoless double-electron capture, an experimental alternative to neutrinoless double-β decay. Method: Two clover germanium detectors were operated underground in coincidence to search for the de-excitation γ rays of 156Gd following the neutrinoless double-electron capture of 156Dy. 231.95 d of data were collected at the Kimballton underground research facility with a 231.57 mg enriched 156Dy sample. Results: No counts were seen above background and half-life limits are set at O (1016-1018) yr for the various decay modes of 156Dy. Conclusion: Low background spectra were efficiently collected in the search for neutrinoless double-electron capture of 156Dy, although the low natural abundance and associated lack of large quantities of enriched samples hinders the experimental reach.

Oxide perovskites with tetravalent dysprosium and compounds of the type Ba/sub 3/RE/sub 4/O/sub 9/ (RE = Rare Earth Element)

Energy Technology Data Exchange (ETDEWEB)

Brauer, G; Kristen, H [Freiburg Univ. (Germany, F.R.)

1980-03-01

In analogy to our investigations concerning tetravalent Nd in oxide perovskites, we also tried to stabilize dysprosium(IV) by incorporation in host-lattices with the perovskite structure. As host-lattices we used BaCeO/sub 3/, BaTbO/sub 3/, and SrTbO/sub 3/. Only in Ba(Ce, Dy)O/sub 3/ we could trace Dy(IV) with certainty. Among the prepared mixed oxides, also the phase Ba/sub 3/Dy/sub 4/O/sub 9/ occured. The lattice parameters of several phases of this latter type were redetermined.

Direct observation of the discrete energy spectrum of two lanthanide-based single-chain magnets by far-infrared spectroscopy

Science.gov (United States)

Haas, Sabrina; Heintze, Eric; Zapf, Sina; Gorshunov, Boris; Dressel, Martin; Bogani, Lapo

2014-05-01

The far-infrared optical transmission has been studied for two lanthanide-based single-chain magnets DyPhOPh and TbPhOPh in the frequency range between 3 and 80 cm-1. The spectra were acquired at temperatures between 2 and 80 K and magnetic fields up to 6 T. Based on their magnetic field dependence in DyPhOPh two of the observed absorption lines are identified as transitions inside the crystal field split Dy3+ ground multiplet 6H15/2, coupled to the neighboring spins. In TbPhOPh one transition was observed inside the crystal-field-split Tb3+ ground multiplet 7F6. The results allow a spectroscopic investigation of the role of single-ion anisotropy and exchange in Glauber dynamics.

Thermodynamics of alternating spin chains with competing nearest- and next-nearest-neighbor interactions: Ising model

Science.gov (United States)

Pini, Maria Gloria; Rettori, Angelo

1993-08-01

The thermodynamical properties of an alternating spin (S,s) one-dimensional (1D) Ising model with competing nearest- and next-nearest-neighbor interactions are exactly calculated using a transfer-matrix technique. In contrast to the case S=s=1/2, previously investigated by Harada, the alternation of different spins (S≠s) along the chain is found to give rise to two-peaked static structure factors, signaling the coexistence of different short-range-order configurations. The relevance of our calculations with regard to recent experimental data by Gatteschi et al. in quasi-1D molecular magnetic materials, R (hfac)3 NITEt (R=Gd, Tb, Dy, Ho, Er, . . .), is discussed; hfac is hexafluoro-acetylacetonate and NlTEt is 2-Ethyl-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl-3-oxide.

Ternary oxide nanostructures and methods of making same

Science.gov (United States)

Wong, Stanislaus S [Stony Brook, NY; Park, Tae-Jin [Port Jefferson, NY

2009-09-08

A single crystalline ternary nanostructure having the formula A.sub.xB.sub.yO.sub.z, wherein x ranges from 0.25 to 24, and y ranges from 1.5 to 40, and wherein A and B are independently selected from the group consisting of Ag, Al, As, Au, B, Ba, Br, Ca, Cd, Ce, Cl, Cm, Co, Cr, Cs, Cu, Dy, Er, Eu, F, Fe, Ga, Gd, Ge, Hf, Ho, I, In, Ir, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Nd, Ni, Os, P, Pb, Pd, Pr, Pt, Rb, Re, Rh, Ru, S, Sb, Sc, Se, Si, Sm, Sn, Sr, Ta, Tb, Tc, Te, Ti, Tl, Tm, U, V, W, Y, Yb, and Zn, wherein the nanostructure is at least 95% free of defects and/or dislocations.

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.

New lanthanide(III) complexes of chiral nonadendate macrocyclic amine derived from (1R,2R)-1,2-diaminocyclohexane and 2,6-diformyl-4-methylphenol

Energy Technology Data Exchange (ETDEWEB)

Paluch, Marta [Department of Chemistry, University of Wroclaw, 14 F. Joliot-Curie, 50-383 Wroclaw (Poland); Lisowski, Jerzy [Department of Chemistry, University of Wroclaw, 14 F. Joliot-Curie, 50-383 Wroclaw (Poland)], E-mail: jurekl@wchuwr.chem.uni.wroc.pl

2008-02-28

The series of complexes [LnH{sub 4}L(NO{sub 3}){sub 2}](NO{sub 3}){sub 2}.nH{sub 2}O (Ln = La, Ce, Pr, Nd, Gd, Tb, Ho, Er, Tm) of the positively charged protonated form of a chiral macrocyclic amine H{sub 4}L{sup +}, derived from the 3 + 3 condensation product of (1R,2R)-1,2-diaminocyclohexane and 2,6-diformyl-4-methylphenol, have been synthesized. The series of complexes Na{sub x}[LnL](X){sub y}(OH){sub x-y}.n(solv) (X = NO{sup 3-} or Cl{sup -}, and Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) of the deprotonated anionic form of the ligand, L{sup 3-}, have also been synthesised. The complexes have been characterised by elemental analyses, {sup 1}H NMR and ESI MS spectra. The X-ray crystal structures of the [LaH{sub 4}L(NO{sub 3}){sub 2}](NO{sub 3}){sub 2}.5CH{sub 3}OH and [GdH{sub 4}L(NO{sub 3}){sub 2}](NO{sub 3}){sub 2}.5CH{sub 3}OH complexes have been determined. The two complexes are isostructural, and the protonated macrocycle acts as pentadentate ligand. The Ln(III) ion is bound to three phenolate oxygen atoms and two amine nitrogen atoms of the macrocyclic ligand and its coordination sphere is completed by the two axial bidendate nitrate anions.

Physical and optical properties of lithium borosilicate glasses doped with Dy3+ ions

Science.gov (United States)

Ramteke, D. D.; Gedam, R. S.; Swart, H. C.

2018-04-01

The borosilicate glasses with Dy3+ ions were prepared by the melt quench technique with varying concentration of Dy2O3. The glasses were characterized by the density calculation, absorbance and photoluminescence (PL) spectroscopy measurements. Density and molar volume of the glasses increases with increase in Dy3+ ions in the glass matrix. This behavior is correlated with the higher molecular weight and larger ionic radius of Dy3+ ion compared to the other constituents of glass matrix. Emission of Dy3+ doped glasses showed three bands at 482, 573 and at 665 nm which correspond to 6H15/2 (blue), 6H13/2 (yellow) and 6H11/2 (red) transitions. The emission spectra of glasses with different concentration of Dy3+ ions shows that, glasses with 0.5 mol% of Dy2O3 shows highest emission and decreases with further doping. CIE 1931 chromaticity diagram showed that the emission of these glasses was in the white region. Photographs of these glasses under 349 nm Light emitting diode excitation also confirmed the white light emission from these glasses.

Coercivity enhancement in Nd-Fe-B sintered permanent magnet by Dy nanoparticles doping

Energy Technology Data Exchange (ETDEWEB)

Liu, W.Q., E-mail: liuweiqiang77@hotmail.co [College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124 (China); Sun, H. [College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124 (China); Yi, X.F. [Anhui Earth-panda Advance Magnetic Material Co., Ltd., Anhui 231500 (China); Liu, X.C.; Zhang, D.T. [College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124 (China); Yue, M., E-mail: yueming@bjut.edu.c [College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124 (China); Zhang, J.X. [College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124 (China)

2010-07-02

Nd-Fe-B permanent magnets with a small amount of Dysprosium (Dy) nanoparticles doping were prepared by conventional sintered method, and the microstructure and magnetic properties of the magnets were studied. Investigation shows that the coercivity rises gradually, while the remanence decreases simultaneously with increased Dy doping amount. As a result, the magnet with 1.5 wt.% Dy exhibits optimal magnetic properties. Further investigation presumed that Dy is enriched as (Nd, Dy){sub 2}Fe{sub 14}B phase in the surface region of the Nd{sub 2}Fe{sub 14}B matrix grains indicated by the enhancement of the magneto-crystalline anisotropy field of the Nd{sub 2}Fe{sub 14}B phase. As a result, the magnet doped with a small amount of Dy nanoparticles possesses remarkably enhanced coercivity without sacrificing its magnetization noticeably.

Evaluation of the exchange interaction and crystal fields in a prototype Dy2 SMM

Science.gov (United States)

Zhang, Qing; Sarachik, Myriam; Baker, Michael; Chen, Yizhang; Kent, Andrew; Pineda, Eufemio; McInnes, Eric

In order to gain an understanding of the INS and magnetization data obtained for Dy2, the simplest member of a newly synthesized family of dysprosium-based molecular magnets, we report on calculations of the magnetic behavior of a Dy2 cluster with the formula [hqH2][Dy2(hq)4(NO3)3].MeOH. The molecular complex contains one high symmetry Dy(III) ion and one low symmetry Dy(III) ion. Our calculations suggest that exchange coupling between the two ions controls the behavior of the magnetization at low temperature, while the crystal field of the low symmetry Dy(III) ion controls the behavior at higher temperature. A point charge electrostatic model, based on crystallographic coordinates, provides a starting point for the determination of the crystal field. Parameters in these calculations are adjusted to provide best fits to inelastic neutron scattering data (INS) and low temperature magnetometry: the INS measurements access crystal field energies and low temperature magnetization probes the Dy-Dy exchange interaction. Work supported by ARO W911NF-13-1-1025 (CCNY) and NSF-DMR-1309202 (NYU).

Luminescent properties in films of ZrO{sub 2}: Dy; Propiedades luminiscentes en peliculas de ZrO{sub 2}: Dy

Energy Technology Data Exchange (ETDEWEB)

Martinez, R. C.; Guzman, J.; Rivera, T.; Ceron, P.; Montes, E.; Guzman, D. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Unidad Legaria, Av. Legaria No. 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Garcia H, M. [UNAM, Instituto de Investigaciones en Materiales, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Falcony, C. [IPN, Centro de Investigacion y de Estudios Avanzados, Apdo. Postal 14-740, 07000 Mexico D. F. (Mexico); Azorin, J., E-mail: rodmarolm@yahoo.com [Universidad Autonoma Metropolitana, Unidad Iztapala, Av. San Rafael Atlixco 186, 09340 Mexico D. F. (Mexico)

2014-08-15

In this work the luminescent characterization of zirconium oxide (ZrO{sub 2}) films impure with dysprosium (Dy{sup +3}) is reported, obtained by means of the ultrasonics spray pyrolysis technique. The films were deposited on glass substrates (Corning), in a temperatures interval of 400 to 550 grades C, using as precursor elements Zirconium oxide chloride octahydrate (ZrOCl{sub 2}·8H{sub 2}O) and Dysprosium tri-chloride (DyCl{sub 3}), dissolved in deionized water, varying the concentration of the contaminated from the 1 to 20 atomic % with relationship to the zirconium in solution. The luminescent characterization was analyzed by means of photoluminescence and thermoluminescence. The photoluminescence results showed a spectrum with three maxima which correspond to the electronic transitions {sup 4}F{sub 9/2} - {sup 6}H{sub 15/2}, {sup 4}F{sub 9/2} - {sup 6}H{sub 13/2} and {sup 4}F{sub 9/2} - {sup 6}H{sub 11/2} characteristics of the Dy{sup 3+} ion. The thermoluminescence (Tl) response when being exposed to a monochrome UV beam in 240 nm showed a wide curve that exhibits a maxim centered in 200 grades C. The Tl response of ZrO{sub 2}:Dy in function of the dose was shown lineal in the interval of 24 mJ/cm{sup 2} to 432 mJ/cm{sup 2}. A study of the repeatability and dissipation of the ZrO{sub 2}:Dy Tl response is included. Considering the shown previous results we can conclude that the ZrO{sub 2} in film form obtained by spray pyrolysis has luminescent properties in 240 nm. (Author)

Magnetic properties of lithium rare-earth fluorides: Ferromagnetism in LiErF4 and LiHoF4 and crystal-field parameters at the rare-earth and Li sites

DEFF Research Database (Denmark)

Hansen, P. E.; Johansson, Torben; Nevald, Rolf

1975-01-01

Single crystals of LiErF4 and LiHoF4 have been grown and their magnetic properties measured from 1.3 K to 300 K. LiHoF4 turned out to be a nearly ideal Ising ferromagnet with TC=1.30±0.05 K and a saturation magnetization along the crystalline c axis of (6.98±0.02)μB. In LiErF4 no ordering...... was observed, but extrapolation indicates that below 0.5 K it will be ferromagnetic with the magnetic moments in the crytalline ab plane. From the susceptibilities the crystal-field parameters Bnm with (n, m)=(2, 0), (4, 0), (4, 4), (6, 0), (6, 4) have been extracted giving for Er3+ in LiErF4: 430., -985......., 1185., -5., 740.+i135. (cm-1) and for Ho3+ in LiHoF4: 470., -825., 1050., -10., 760.+i150 (cm-1). The exchange constants were found to be small compared to the dipole interactions. Furthermore the 7Li NMR spectra have been obtained in these materials as well as in LiTbF4 thereby determining the second...

Thermoluminescent properties of CaSO4:Dy prepared by precipitation method

International Nuclear Information System (INIS)

Roman, J.; Rivera, T.; Azorin, J.

2009-10-01

This paper reports the synthesis and thermoluminescent (Tl) characterization of CaSO 4 :Dy obtained by the precipitation method. Thermoluminescent CaSO 4 :Dy powder and Teflon (PTFE) were mixed in order to obtain samples in pellets form. Samples of CaSO 4 :Dy were exposed to a radiation gamma source of 60 Co and 90 Sr beta particles. Tl response of CaSO 4 :Dy showed a glow curve with two peaks centered at around 164 and 302 C. Tl phosphor showed a good linearity in the range from 0.5 to 30 Gy. Fading of the Tl information was 5.19 % in 37 days and presented a standard deviation of 4% for reproducibility. (Author)

Reaction rate constant of HO2+O3 measured by detecting HO2 from photofragment fluorescence

Science.gov (United States)

Manzanares, E. R.; Suto, Masako; Lee, Long C.; Coffey, Dewitt, Jr.

1986-01-01

A room-temperature discharge-flow system investigation of the rate constant for the reaction 'HO2 + O3 yields OH + 2O2' has detected HO2 through the OH(A-X) fluorescence produced by photodissociative excitation of HO2 at 147 nm. A reaction rate constant of 1.9 + or - 0.3 x 10 to the -15th cu cm/molecule per sec is obtained from first-order decay of HO2 in excess O3; this agrees well with published data.

The study on production of CaSO4 (Dy) dosimeters

International Nuclear Information System (INIS)

Sriratchatchaval, V.

1989-05-01

The purpose of this experiment is to find out the techniques of preparation and production and to study the characteristic of Thermoluminescence Dosimeter (TLD); CaSO 4 (Dy). This dosimeter is produced as pellets with 1.0 mm thickness and diameter 4.8 mm, which is suitable for gamma rays and X-rays detector. CeSO 4 (Dy) is prepared by adding Dy 2 O 3 (0.2 mole %Dy) to CaSO 4 .2H 2 O then taking this mixture to crystallize in conc. H 2 SO 4 at 300 0 C responds linearly to gamma rays in the range of 0.01-100 mGy and gives the highest peak at 205 0 C. This TLD is fading 3% per month, low sensitivity to light and the response of signal depends on the energy level of gamma rays

A study of the structure of 162Dy through the (n,γ) and (n,e-) reactions

International Nuclear Information System (INIS)

Warner, D.D.; Shi, Z.R.; Gelletly, W.; Borner, H.G.; Hoyler, F.; Schreckenbach, K.; van Isacker, P.

1987-01-01

The level structure below 2 MeV in 162 Dy has been investigated using the 161 Dy(n,γ) 162 Dy and 161 Dy(n,e - ) 162 Dy reactions. The results for the positive parity excitations are discussed within the framework of an Interacting Boson Approximation (IBA-2) calculation. 7 refs., 1 fig., 1 tab

Host markers in Quantiferon supernatants differentiate active TB from latent TB infection: preliminary report

Directory of Open Access Journals (Sweden)

Walzl Gerhard

2009-05-01

Full Text Available Abstract Background Interferon gamma release assays, including the QuantiFERON® TB Gold In Tube (QFT have been shown to be accurate in diagnosing Mycobacterium tuberculosis infection. These assays however, do not discriminate between latent TB infection (LTBI and active TB disease. Methods We recruited twenty-three pulmonary TB patients and 34 household contacts from Cape Town, South Africa and performed the QFT test. To investigate the ability of new host markers to differentiate between LTBI and active TB, levels of 29 biomarkers in QFT supernatants were evaluated using a Luminex multiplex cytokine assay. Results Eight out of 29 biomarkers distinguished active TB from LTBI in a pilot study. Baseline levels of epidermal growth factor (EGF soluble CD40 ligand (sCD40L, antigen stimulated levels of EGF, and the background corrected antigen stimulated levels of EGF and macrophage inflammatory protein (MIP-1β were the most informative single markers for differentiation between TB disease and LTBI, with AUCs of 0.88, 0.84, 0.87, 0.90 and 0.79 respectively. The combination of EGF and MIP-1β predicted 96% of active TB cases and 92% of LTBIs. Combinations between EGF, sCD40L, VEGF, TGF-α and IL-1α also showed potential to differentiate between TB infection states. EGF, VEGF, TGF-α and sCD40L levels were higher in TB patients. Conclusion These preliminary data suggest that active TB may be accurately differentiated from LTBI utilizing adaptations of the commercial QFT test that includes measurement of EGF, sCD40L, MIP-1β, VEGF, TGF-α or IL-1α in supernatants from QFT assays. This approach holds promise for development as a rapid diagnostic test for active TB.

Phosphors doped with Dy3+ and Gd3+ for lighting

International Nuclear Information System (INIS)

Su, Q; Pei, Z.; Zeng, Q.; Chi, L.

1998-01-01

Full text: Some heavy lanthanide ions with even atomic number such as Dy 3+ and Gd 3+ are abundant in the ion adsorption type deposit of China. Their price is cheap and they have specific spectroscopic properties which can be used as phosphors. Dy 3i on has two dominant bands in the emission spectrum. The yellow band (575 nm) corresponds to the hypersensitive transition 4 F 9/2 → 6 H 13/2 (ΔL=2, ΔJ=2), and the blue band (485 nm) corresponds to the 4 F 9/2 → 6 H 15/2 transition. Factors which influence on the yellow- to-blue intensity ratio (Y/B) were investigated. Adjusting to a suitable Y/B, Dy 3+ will emit white light with high colour temperature and can be used for lighting. But Dy 3+ ion has only narrow excitation bands of f-f transitions ranging from 300-500 nm, no broad excitation band such as charge transfer band or f-d transition band exists in the UV region 200-300 nm. Hence its luminescent efficiency is low when it is excited by UV radiation emitted from the mercury plasma. This is one of the drawbacks to its use as lamp phosphor. However, this can be overcome by sensitisation with Gd 3+ , Pb 2+ or other sensitisers such as vanadate shown in this report. Gd 3+ is not only a good matrix, but also a good sensitiser. Using its 8 S 7/2 → 6 D, 6 I and 6 P transitions, the UV excitation energy can be absorbed and transferred to the activator such as Dy 3+ . Therefore, in some cases Gd 3+ is better than Y 3+ which is optical inert as a matrix. For the phosphor Ca 1.96 Pb 0.04 RE 7.9 Dy 0.1 (SiO 4 ) 6 O 2 prepared by sol-gel method, the intensity of Dy 3+ in the Gd 3+ compound (RE=Gd 3+ ) is six times that in the Y 3+ compound. Some new phosphors doped with Dy 3+ and Gd 3+ prepared in our laboratory are reported

Treatment Outcomes of Patients with Multidrug-Resistant Tuberculosis (MDR- TB) Compared with Non-MDR-TB Infections in Peninsular Malaysia.

Science.gov (United States)

Elmi, Omar Salad; Hasan, Habsah; Abdullah, Sarimah; Mat Jeab, Mat Zuki; Ba, Zilfalil; Naing, Nyi Nyi

2016-07-01

Treating patients with multidrug-resistant tuberculosis (MDR-TB) strains is more complicated, complex, toxic, expensive, than treating patients with susceptible TB strains. This study aims to compare the treatment outcomes and potential factors associated between patients with MDR-TB and non MDR TB infections in peninsular Malaysia. This study was a retrospective cohort study. Data were collected from the medical records of all registered MDR-TB patients and Non-MDR-TB patients at five TB hospitals in peninsular Malaysia from January 2010 to January 2014. A total of 314 subjects were studied, including 105 MDR-TB cases and 209 non-MDR-TB. After TB treatment, 24.8% of the MDR-TB patients and 17.7% of non MDR TB relapsed; 17.1% of the MDR-TB patients and 16.3% of non MDR TB defaulted from TB treatment. A significant difference seen in treatment success rate 17.1% for MDR-TB; 63.1% for non MDR TB (P history of TB treatment, and presence of HIV infection.

Mycobacteria and TB