Red, green, and blue upconversion luminescence of trivalent-rare-earth ion-doped Y2O3 nanocrystals

Effects of several rare earths and yttrium on isolated frog sartorius muscles were investigated. Lanthanum (La), praseodymium, neodymium (Nd), samarium, gadolinium, dysprosium, erbium, thulium, ytterbium, and yttrium (Y) inhibited twitch tension of indirectly stimulated preparations. Concentrations required to reduce twitch tension to 50% of control tension in 15 min ranged between 0.52 mM and 1.10 mM (Ringer solution; pH 6.0). Similar concentrations (La, Nd, and Y) also inhibited twitch tension of directly stimulated, curarized preparations. A relationship between effect on twitch tension and atomic number was not found. La (0.3 mM) and Y (0.3 mM) reduced the amplitude, but did not appear to alter the time course, of extracellularly recorded end-plate potentials (E.P.P.'s). Amplitudes of intracellularly recorded E.P.P.'s were reduced by La (0.0125–0.05 mM) and Y (0.0125 and 0.025 mM). Effect on quantal contents of E.P.P.'s indicated that the principal action of both agents was an inhibition of transmitter release. La (0.025 and 0.05 mM) and Y (0.05 mM) significantly increased the frequency of miniature end-plate potentials. It is concluded that the prejunctional membrane does not differentiate significantly between the action of the trivalent rare earth ion lanthanum and the action of the trivalent rare-earth-like ion yttrium.

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Spectroscopic research of upconversion nanomaterials based on complex oxide compounds doped with rare-earth ion pairs: Benefit for cancer diagnostics by upconversion fluorescence and radio sensitive methods/Spektroskopische Untersuchung von mit Ionenpaaren Seltener Erden dotierten Upconversion-Nanokompositen: Nutzen für die Krebsdiagnostik durch Upconversion-Fluoreszenz und strahlungssensitive Methoden

Photonics and Lasers in Medicine ◽

10.1515/plm-2013-0013 ◽

2013 ◽

Vol 2 (2) ◽

Cited By ~ 17

Author(s):

Anastasia V. Ryabova ◽

Daria V. Pominova ◽

Victoria A. Krut’ko ◽

Maria G. Komova ◽

Victor B. Loschenov

Keyword(s):

Rare Earth ◽

Upconversion Luminescence ◽

Ion Pairs ◽

Biological Tissues ◽

Cancer Diagnostics ◽

Inorganic Nanoparticles ◽

Deep Penetration ◽

Rare Earth Ion ◽

Biological Studies ◽

Upconversion Nanocrystals

AbstractHighly photochemically stable nanoparticles, in which upconversion luminescence can be excited – so-called upconversion nanocrystals (UC-NCs) – exhibit widely separated (up to 500 nm) narrow luminescence bands in the visible (VIS) region located far from the excitation near-infrared (NIR) laser radiation, and thus can be more easily identified compared to organic luminophores and semiconductor nanoparticles. Due to a deep penetration of exciting infrared (IR) radiation, the absence of parasitic fluorescence of biomolecules and the absence of phototoxicity and photobleaching upon near IR excitation, UC-NCs can be efficiently used as fluorescent probes in biological studies and fluorescence diagnostics (FD). The doping of such nanoparticles with GdWe studied the upconversion characteristics of inorganic nanoparticles made of different materials doped with rare-earth ion (REI) pairs YbBased on the results obtained, the matrix LaThe investigated complex polycrystalline oxide compounds are promising as diagnostic agents for biological tissues visualization by fluorescence, light scattering, and nuclear magnetic resonance imaging.

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ChemInform Abstract: Trivalent Rare Earth Ion Conduction in the Rare Earth Tungstates with the Sc2(WO4)3-Type Structure.

ChemInform ◽

10.1002/chin.199839010 ◽

2010 ◽

Vol 29 (39) ◽

pp. no-no

Author(s):

N. IMANAKA ◽

Y. KOBAYASHI ◽

K. FUJIWARA ◽

T. ASANO ◽

Y. OKAZAKI ◽

...

Keyword(s):

Rare Earth ◽

Type Structure ◽

Rare Earth Ion ◽

Ion Conduction ◽

Trivalent Rare Earth ◽

The Rare Earth

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Trivalent Rare Earth Ion Conduction in the Rare Earth Tungstates with the Sc2(WO4)3-Type Structure

Chemistry of Materials ◽

10.1021/cm980157e ◽

1998 ◽

Vol 10 (7) ◽

pp. 2006-2012 ◽

Cited By ~ 59

Author(s):

Nobuhito Imanaka ◽

Yasuyuki Kobayashi ◽

Kazuyasu Fujiwara ◽

Takuya Asano ◽

Yusuke Okazaki ◽

...

Keyword(s):

Rare Earth ◽

Type Structure ◽

Rare Earth Ion ◽

Ion Conduction ◽

Trivalent Rare Earth ◽

The Rare Earth

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INVESTIGATION OF THE SAMARIUM ROLE IN THE PHYSICAL PROPERTIES OF Sm0.5Re0.5Ba2Cu3O7−δ COMPOUNDS IN THE ORTHORHOMBIC AND TETRAGONAL STRUCTURES

Modern Physics Letters B ◽

10.1142/s0217984991001192 ◽

1991 ◽

Vol 05 (14n15) ◽

pp. 969-984 ◽

Cited By ~ 7

Author(s):

N. GUSKOS ◽

W. LIKODIMOS ◽

C. A. LONDOS ◽

Ch. TRIKALINOS ◽

A. KOUFOUDAKIS ◽

...

Keyword(s):

Phase Transition ◽

Rare Earth ◽

Superconducting Phase ◽

Rare Earth Ions ◽

Epr Spectrum ◽

Rare Earth Ion ◽

Low Field ◽

Trivalent Rare Earth ◽

Epr Signal ◽

Superconducting Phase Transition

Perovskites of type Sm 0.5 Re 0.5 Ba 2 Cu 3 O 7−δ (Re=Y, La, Nd, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu) have been investigated by XRD, magnetic and EPR measurements in both orthorhombic and tetragonal phases. In the former case the usual superconducting phase transition in the range 90 to 95 K has been detected. In all the compounds an EPR spectrum of Cu 2+ ions has been observed. In the tetragonal phase, the EPR spectra of trivalent rare earth ions have been recorded for some members of the series. The observation of a broad EPR signal, tentatively attributed to superexchange interaction over the oxygen bridges < O 2), has also been recorded. Furthermore, the intensity of low-field microwave absorption has been found to depend strongly on the nature of the substituted rare earth ion at the sites of Y ions of the YBa 2 Cu 3 O 7−δ type compounds.

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THE MAGNETIC AND ELECTRICAL PROPERTIES OF RARE-EARTH Sm3+ SUBSTITUTED Bi1.7Pb0.3Sr2Ca2-xSmxCu3O12 SYSTEM

Modern Physics Letters B ◽

10.1142/s0217984905008372 ◽

2005 ◽

Vol 19 (06) ◽

pp. 331-340 ◽

Cited By ~ 7

Author(s):

AHMET EKİCİBİL ◽

ATILLA COŞKUN ◽

BEKIR ÖZÇELİK ◽

KERIM KIYMAÇ

Keyword(s):

Magnetic Field ◽

Rare Earth ◽

Hole Concentration ◽

Superconducting Properties ◽

Rare Earth Ion ◽

Different Temperatures ◽

Ion Substitution ◽

Trivalent Rare Earth ◽

Increasing Temperature ◽

Magnetic Nature

In the present work, the magnetic properties of high-Tc Bi 1.7 Pb 0.3 Sr 2 Ca 2-x Sm x Cu 3 O 12 system (x = 0.03) have been investigated, for different temperatures below Tc. Substitution of Sm 3+ for Ca 2+ is found to change the superconducting properties of the system, despite the weak paramagnetic nature of the Sm 3+ ion. The dc magnetization measurements performed on the compound reveal that the superconducting regions decrease with increasing temperature and magnetic field. The results are explained on the basis of a possible reduction of hole concentration with trivalent rare-earth ion substitution, and also on the basis of the magnetic nature of the substituted Sm 3+ ions.

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