Rare Earth Ions
Mostrando 1-12 de 59 artigos, teses e dissertações.
-
1. Characterization of CBD-CdS Doped with Some Rare Earths III (Eu3+,Ce3+) as Function of Synthesis Time
Rare earths (Europium, cerium)-doped CdS nanofilms are prepared using the growth technique chemical bath deposition (CBD) at the reservoir temperature of 70±2°C varying the synthesis time in a wide range. For the rare earths doped CdS nanofilms the synthesis time was ranged from 80 to 135 min. The rare earths molar concentration was in the range 0.0≤x≤
Mat. Res.. Publicado em: 01/02/2018
-
2. Rare Earth-Indomethacinate Complexes with Heterocyclic Ligands: Synthesis and Photoluminescence Properties
In this work, synthesis, characterization and photophysical properties of trivalent rare earth complexes with a nonsteroidal anti-inflammatory drug [the indomethacinate (indo), presenting formulas RE(indo)3(H2O)x (x = 3, for Eu3+ and Gd+3, and x = 4 for Tb+3), RE(indo)3(bipy) and RE(indo)3(phen) (bipy: 2,2'-bipyridine, and phen: 1,10-phenanthroline)] were in
J. Braz. Chem. Soc.. Publicado em: 2017-12
-
3. Luminescent and Magnetic Properties of Fe3O4@SiO2:phen:Eu3+
Magnetite was doped with rare earth ions (europium) to produce core-shell materials with both magnetic and luminescent properties, i.e., a magnetic Fe3O4 oxide core and a SiO2:phen:Eu3+ shell. The resulting material was analyzed by X-ray powder diffraction and transmission electron microscopy, and subjected to magnetic and luminescence emission measurements.
Mat. Res.. Publicado em: 24/06/2017
-
4. On-line Green Solid Phase Extraction of Trace Rare Earth Elements and Uranium in Environmental Samples and ICP OES Detection
An on-line solid phase extraction (SPE) method using mini column packed with natural sorbent based on cotton roll dyed by quinalizarin was developed for simultaneously pre-concentration of rare earth elements and uranium at trace levels in environmental samples followed by inductively coupled plasma optical emission spectrometry (ICP OES) determination. Vari
J. Braz. Chem. Soc.. Publicado em: 2016-10
-
5. Optically Detected Thermal Effects in Rare-Earth Doped Materials for Host Characterization, Thermometric Devices, Nanothermometry and Biothermometry
We present a review of recent works on optically investigated thermal effects in crystalline and amorphous materials doped with trivalent rare-earth (RE) ions. The paper describes how the frequency upconversion (UC) photoluminescence (PL) technique is used to investigate the thermal behavior of samples and how to perform optical measurements of temperature.
J. Braz. Chem. Soc.. Publicado em: 2015-12
-
6. Near Infrared Emission at 1000 nm from Nanostructured Pr3+/Yb3+ Co-doped SiO2-Nb2O5 for Solar Cell Application
Energy conversion, involving UV and Vis absorption to generate near infrared (NIR) emission at 1000 nm from nanostructured Pr3+/Yb3+ co-doped SiO2-Nb2O5 for solar cell application was the main focus of this work. The synthesis, structural and optical characterization of Pr3+/Yb3+ co-doped 70SiO2-30Nb2O5 nanocomposites and planar waveguides prepared by the so
J. Braz. Chem. Soc.. Publicado em: 2015-12
-
7. Eco-Friendly Luminescent Hybrid Materials Based on EuIII and LiI Co-Doped Chitosan
Biopolymer-based materials have been of particular interest as alternatives to synthetic polymers due to their low toxicity, biodegradability and biocompatibility. Among them, chitosan is one of the most studied ones and has recently been investigated for the application as solid state polymer electrolytes. Furthermore, it can serve as a host for luminescent
J. Braz. Chem. Soc.. Publicado em: 2015-12
-
8. Determination of rare earth elements in spent catalyst samples from oil refinery by dynamic reaction cell inductively coupled plasma mass spectrometry
A determinação de elementos terras raras (REE) em catalisadores gastos provenientes da indústria de petróleo é proposta. Foram testados três procedimentos de tratamento de amostra, um sem adição de HF e outros dois usando diferentes quantidades de HF e ácido bórico, além de uma etapa de evaporação assistida por radiação micro-ondas para dissol
J. Braz. Chem. Soc.. Publicado em: 2014-06
-
9. ESTUDO DO COMPORTAMENTO PTCR EM CERÂMICAS DE BCT DOPADAS COM ÍONS TERRA RARAS. / STUDY OF BEHAVIOR IN PTCR CERAMICS BCT OF RARE EARTH IONS DOPED.
O titanato de bário (BaTiO3 - BT) é um material ferroelétrico com importantes aplicações tecnológicas. Quando dopado com íons trivalentes no sítio do bário ou pentavalentes no sítio do titânio, cerâmicas de BaTiO3 exibem um caráter semicondutor, acompanhado por um coeficiente positivo da resistência com o aumento da temperatura (PTCR). Diversas
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 09/02/2012
-
10. Effect of rare earth ions on transition temperature in perovskite materials by on-line ultrasonic studies
On-line measurements of ultrasonic longitudinal velocity, shear velocity and longitudinal attenuation were carried out on R1-xSr xMnO3 perovskites (R = La, Pr, Nd and Sm) for different compositions of Sr, at a fundamental frequency of 5 MHz over wide range of temperatures using the through-transmission method. The observed maxima/minima in velocities and att
Materials Research. Publicado em: 26/06/2012
-
11. Produção e caracterização de vidros de telureto tridopados com íons de terras raras e nanopartículas metálicas para uso em displays coloridos. / Production and characterization of tellurite glasses doped with rare earth ions and metallic nanoparticles for use in color displays.
This works presents studies of the production and the characterization of TeO2 -PbO-GeO2 doped with erbium, thulium and ytterbium ions and also prepared with different metallic nanoparticles for applications in displays. This glass system presents a broad transmission window in the visible and infrared (350 - 6500 nm), high solubility for rare earth ions, lo
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 08/04/2011
-
12. Fases magnéticas de sistemas nanoestruturados de terras-raras
There is presently a worldwide interest in artificial magnetic systems which guide research activities in universities and companies. Thin films and multilayers have a central role, revealing new magnetic phases which often lead to breakthroughs and new technology standards, never thought otherwise. Surface and confinement effects cause large impact in the m
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 04/02/2011