Luminescence Efficiency
Mostrando 1-12 de 23 artigos, teses e dissertações.
-
1. Near-Infrared Luminescence from Visible-Light-Sensitized Ruthenium(II)-Neodymium(III) Heterobimetallic Bridged Complexes Containing Alkoxy(silyl) Functional Groups
New infrared emitting d-f (ruthenium(II)-neodymium(III)) heterobimetallic complexes with alkoxy(silyl) functional groups have been prepared. Visible excitation evidenced energy transfer processes from the ruthenium(II) donor to neodymium(III) acceptors leading to infrared emission. Energy transfer rates (kEnT) and efficiency of energy transfer (ηEnT) are, r
J. Braz. Chem. Soc.. Publicado em: 2020-04
-
2. JUDD-OFELT ANALYSIS OF Tb3+ AND UPCONVERSION STUDY IN Yb3+-Tb3+ CO-DOPED CALIBO GLASSES
We report on the study of the spectroscopic properties in Ytterbium-Terbium (Yb3+-Tb3+) co-doped calcium lithium borate (CaLiBO) glasses, with the study’s focus being on the upconversion process. Intensity parameters Ωλ for CaLiBO:Tb3+ are determined by the Judd-Ofelt method to be Ω2 = 15.5 × 10-20 cm2, Ω4 = 1.90 × 10-20 cm2 and Ω6 = 3.69 × 10-20 c
Quím. Nova. Publicado em: 2020-02
-
3. Synthesis and Characterization of Nb2O5:La3+,Eu3+ Phosphors Obtained by the Non-Hydrolytic Sol-Gel Process
The phosphor-converted light-emitting diode technique is an important solid-state illumination strategy. Sulfide-based materials are the most often employed red phosphors, but they are chemically unstable and present lower efficiency in comparison to the blue and green phosphors. Therefore, it is important to find a new red phosphor source that can emit inte
J. Braz. Chem. Soc.. Publicado em: 2015-12
-
4. Low Temperature Synthesis of Luminescent RE2O3:Eu3+ Nanomaterials Using Trimellitic Acid Precursors
[RE(TLA)·(H2O)n:Eu3+] (RE3+: Y, Gd and Lu; TLA: trimellitic acid) precursor complexes were synthesized by an one step aqueous co-precipitation method. After annealing for 1 h, RE2O3:Eu3+ nanophosphors were formed through the benzenetricarboxylate low temperature thermolysis method (500-1000 ºC). The compounds were characterized by using different technique
J. Braz. Chem. Soc.. Publicado em: 2015-12
-
5. Re(I) complexes and TiO2 films in photoinduced molecular devices / Complexos de Re(I) e filmes de TiO2 em dispositivos moleculares fotoinduzidos
The thesis focus on two main topics: characterization of TiO2 films for Dye-sensitized solar cells, DSCs, and investigation on photochemical and photophysical properties of Re(I) polypyridyl complexes. Mesoporous TiO2 films were prepared by sol-gel method and by commercial oxide (P25, Degussa) and were characterized by XRD, SEM, B.E.T. and XPS. Both oxides w
Publicado em: 2009
-
6. Development of luminescent systems based on PHB and PMMA polymers doped with rare earth complexes / Desenvolvimento de sistemas luminescentes à base dos polímeros PHB e PMMA dopados com complexos de terras raras
This work presents the preparation, characterization and studies of photoluminescence properties based on trivalent rare earth coordination complexes of βdiketonates and salicylates (β-diketonates = acac- and tta-; salicylates = Hsal- and RE3+ = Sm3+, Eu3+, Gd3+ and Tb3+) doped into polymers PHB (poly3hydroxybutyrate) and PMMA (polymethylmethacryla
Publicado em: 2009
-
7. Study of organic light-emitting devices using rare earth and transition metals complexes. / Estudo de dispositivos orgânicos emissores de luz empregando complexos de terras raras e de metais de transição.
This work presents the study of the Rare Earth (RE) and Transition Metals (TM) complexes, as emissive layers of Organic Light-Emitting Devices (OLEDs) designed, built and electro-optically characterized. The thin films were thermally evaporated or spin-coated. This research started with the study of Europium complex changing its central ligand (CL), which sh
Publicado em: 2008
-
8. Redes de coordenaÃÃo com Ãons lantanÃdeos: sÃntese, caracterizaÃÃo e estudo espectroscÃpio
This work shows the synthesis of new metalorganic frameworks containing Eu3+ and Gd3+ ions, using 1,3,5,-benzenetrisbenzoic acid (H3BTB) as ligand. The H3BTB was synthesized in two steps and characterized by elemental analysis, infrared spectroscopy and nuclear magnetic resonance 1H and 13C; the obtained results confirm all literature dataâs. Networks of co
Publicado em: 2008
-
9. Compostos de Cério como Redutores de Fuligem no Uso de Biodiesel como Combustível / Compostos de cério como redutores de fuligem no uso de biodiesel como combustível
In the work, the complex Ce(hdacac)6·xH2O (x0-2) was synthesized in order to produce an additive capable of reducing soot, that is emitted from the combustion of diesel, biodiesel and its mixtures in compression engines. The complexes were produced from a new ligand, 3-hexadecylpentane-2,4-dione (hdacac), that has a long alkyl chain and two carbonyl groups
Publicado em: 2008
-
10. STUDY OF THE AGGREGATION AND PHOTOBLEACHING DYNAMIC OF METHYLENE BLUE AND ORTO-TOLUIDINE BLUE AS REGARDS THEIR PHOTODYNAMIC EFFECTIVENESS / Estudo da dinâmica de fotodegradação e agregação das fenotiazinas azul de metileno e azul orto-toluidina com relação à eficiência fotodinâmica
Photodynamic therapy may be a viable alternative to treat localized infections, although to obtain a resourceful clinical application, parameters linked with photodynamic efficiency must be analyzed in order to achieve quantifiable results. The aims of this study were to investigate the aggregation dynamic of the photosensitizers methylene blue and orto-tolu
Publicado em: 2007
-
11. SÃntese e estudo espectroscÃpico de complexos de Ãons lantanÃdeos incorporados em materiais hÃbridos orgÃnicos-inorgÃnicos
In this work two new europium and gadolinium b-diketonate complexes, [Ln(btfa)3(4,4 -bpy)(EtOH)] (Ln = Eu, Gd; 4,4 -bpy = 4,4 -bipyridine; btfa = 4,4,4- trifluoro-l-phenyl- 1,3-butanedione), were prepared and incorporated into a organicinorganic hybrid material. The general formulae of these complexes were confirmed by X-rays single crystal data and elementa
Publicado em: 2007
-
12. DiagÃnese acelerada de caulim à zeÃlita NaA para uso no abrandamento de Ãguas. / DiagÃnese sped up of kaolinm to the zeolite NaA (LTA)for use in the water softener.
Zeolite NaA (LTA) has been successfully synthesized by hydrothermal route, in which kaolim was used as silicon and aluminum source. The obtained zeolite was characterized by X-ray diffraction, X-ray absorption, thermogravimetry (TG), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), infrared absorption spectroscopy (IR), luminescen
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 31/03/2006