SIZE-DEPENDENT UPCONVERSION PROPERTIES OF Er3+ DOPED NANO Y2O3 PARTICLES

Size-dependent upconversion properties for Er 3+-doped Y 2 O 3 nano-crystal have been investigated. The investigation shows that the reduction of the particle size intensifies the hypersensitive 2 H 11/2 → 4 I 15/2 transition, decreasing the intensity ratio of the 4 S 3/2 → 4 I 15/2 transition to the 2 H 11/2 → 4 I 15/2 one. The enhanced non-radiative decay probability and the intensified energy transfers in the small particles also enhance the population of the 4 F 9/2 level, leading to the increase of the intensity ratio of the red to the green one. It is believed that the absorbed hydroxyl and carbonate groups on the surface as well as the lowered symmetry of the local surroundings of the doped Er 3+ ions near the surface result in the size-dependent luminescence properties in the nano-crystal.

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Observation of the quantum size effect in the STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153129 ◽

1989 ◽

Vol 47 ◽

pp. 230-231

Author(s):

F. Ouyang ◽

M. Isaacson

Keyword(s):

Particle Size ◽

Size Effect ◽

Surface Plasmon ◽

Bulk Material ◽

Blue Shift ◽

Quantum Size Effect ◽

Large Momentum ◽

Small Particles ◽

Size Dependent ◽

Quantum Size

The study of small particles or microclusters has been very active in recent years. When the particle size becomes smaller, its electronic properties deviate from those of bulk material and become size dependent. This phenomenon is refered to as the quantum size effect.One of the frequently used probes for studying the electronic states of small particles is the surface plasmon (SP) excitation. Genzel et al. studied the optical absorption peaks from silver particles in glass. They found a blue shift of the SP peak when the particle size becomes smaller (see Fig 2). Electron energy loss spectroscopy (EELS) studies have also been performed. Recently vom Felde et al. reported broad beam EELS with large momentum transfer from potassium particles embedded in a MgO matrix. They observed that the surface plasmon energy increases when particle size becomes smaller, and there is a positive dispersion for particles of size 40 Å.

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Morphology and Particle Size Dependent Luminescence Properties of Y2O3:Eu Phosphors Prepared by Various Synthetic Methods

ECS Meeting Abstracts ◽

10.1149/ma2012-02/57/3925 ◽

2012 ◽

Keyword(s):

Particle Size ◽

Synthetic Methods ◽

Luminescence Properties ◽

Size Dependent

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First experimental determination of the radiative-decay probability of the 31− state in 12C for estimating the triple alpha reaction rate in high temperature environments

Physics Letters B ◽

10.1016/j.physletb.2021.136283 ◽

2021 ◽

pp. 136283

Author(s):

M. Tsumura ◽

T. Kawabata ◽

Y. Takahashi ◽

S. Adachi ◽

H. Akimune ◽

...

Keyword(s):

High Temperature ◽

Experimental Determination ◽

Reaction Rate ◽

Radiative Decay ◽

Decay Probability ◽

Triple Alpha

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Comparison of the Bone Harvesting Capacity of an Intraoral Bone Harvesting Device and Three Different Implant Drills

BioMed Research International ◽

10.1155/2017/7819080 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Hyun-Chang Lim ◽

Kyung-In Ha ◽

Ji-Youn Hong ◽

Ji-Young Han ◽

Seung-Il Shin ◽

...

Keyword(s):

Particle Size ◽

Dry Weight ◽

Volumetric Measurement ◽

Small Particles ◽

Low Speed ◽

Bone Particle ◽

Bone Harvesting ◽

Bone Particles

The aim of the present study was to compare bone-collecting capacity of bone harvesting device and minimally irrigated low-speed drilling using three implant systems. One bone harvesting device and three commercially available drill systems were compared using the osteotomies on bovine rib bones. The amount of the collected bone particle and particle size (<500 μm: small, 500–1000 μm: medium, and >1000 μm: large) were measured. Total wet (1.535±0.232 mL) and dry volume (1.147±0.425 mL) of the bone particles from bone harvesting device were significantly greater than three drill systems (wet volume: 1.225±0.187–1.27±0.29 mL and dry volume: 0.688±0.163–0.74±0.311 mL) (P<0.05). In all groups, the amount of large sized particles in wet and dry state was the greatest compared to that of medium and small particles. The dry weight of the bone particles showed the same tendency to volumetric measurement. In conclusion, total bone particles and large sized particles (>1000 μm) were harvested significantly greater by bone harvesting device than minimally irrigated low-speed drilling. The composition of particle size in all harvesting methods was similar to each other.

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Up-conversion emission and in vitro cytotoxicity characterization of blue emitting, biocompatible SrTiO3 nanoparticles activated with Tm3+ and Yb3+ ions

RSC Advances ◽

10.1039/c6ra03075k ◽

2016 ◽

Vol 6 (45) ◽

pp. 39469-39479 ◽

Cited By ~ 3

Author(s):

R. Pazik ◽

A. Zięcina ◽

B. Poźniak ◽

M. Malecka ◽

L. Marciniak ◽

...

Keyword(s):

Particle Size ◽

Cytotoxic Effect ◽

In Vitro Cytotoxicity ◽

Ion Release ◽

Size Dependent ◽

U2os Cells

Blue emitting, up-converting NP's of SrTiO3:Tm3+/Yb3+ synthesized using the citric route are biocompatible towards J774.E whereas the cytotoxic effect to U2OS cells is not particle size dependent but most probably is related to Sr2+ ion release.

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Particle size dependent hysteresis loss in La0.7Ce0.3Fe11.6Si1.4C0.2 first‐order systems

Applied Physics Letters ◽

10.1063/1.3684244 ◽

2012 ◽

Vol 100 (7) ◽

pp. 072403 ◽

Cited By ~ 46

Author(s):

F. X. Hu ◽

L. Chen ◽

J. Wang ◽

L. F. Bao ◽

J. R. Sun ◽

...

Keyword(s):

Particle Size ◽

Hysteresis Loss ◽

First Order ◽

Size Dependent

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Size-dependent solution-mediated phase transformation of piroxicam monohydrate particles

CrystEngComm ◽

10.1039/d1ce00237f ◽

2021 ◽

Vol 23 (16) ◽

pp. 2928-2932

Author(s):

Changlin Yao ◽

Lei Wang ◽

Xinyuan Wang ◽

Xutang Tao

Keyword(s):

Particle Size ◽

Phase Transformation ◽

Size Dependent

The transformation from the piroxicam monohydrate to form I or form II could be achieved precisely by adjusting the particle size itself in the 99% acetone-1% H2O solvent at 31 °C.

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Up- and Downconversion Luminescence Properties of Nd3+Ions Doped in Bi2O3–BaO–B2O3Glass System

Advances in Materials Science and Engineering ◽

10.1155/2014/751973 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 5

Author(s):

R. Ruamnikhom ◽

P. Limsuwan ◽

M. Horprathum ◽

N. Chanthima ◽

H. J. Kim ◽

...

Keyword(s):

Radiative Decay ◽

Excited State Absorption ◽

Upconversion Emission ◽

Luminescence Properties ◽

Barium Borate ◽

Melt Quenching ◽

Strong Fluorescence ◽

Nir Emission ◽

Quenching Method ◽

Barium Borate Glass

Physical, optical, and luminescence properties of Nd3+ions in bismuth barium borate glass system were studied. The glasses prepared by a melt quenching method were doped at various Nd2O3concentrations in compositions (40-x)B2O3 : 40Bi2O3 : 20BaO : xNd2O3(wherex= 0.00, 0.50, 1.00, 1.50, 2.00, and 2.50 in mol%). Luminescence properties of the glasses were studied under two excitations of 585 and 750 nm for downconversion. From both excitations, the results show emission bands in NIR region corresponding to the transitions between4F3/2 → 4I9/2(900 nm),4F3/2 → 4I11/2(1,060 nm), and4F3/2 → 4I13/2(1,345 nm). The luminescence intensity obtained with 585 nm excitation was stronger than 750 nm, with the strongest NIR emission at 1,060 nm. The upconversion emission spectrum exhibits strong fluorescence bands in the UV region at 394 nm (λex=591 nm). The processes are associated with excited state absorption (ESA) from4F3/2level to4D3/2level and it is the radiative decay from the4D3/2to ground levels (4D3/2 → 4I13/2) which are responsible for the emission at 394 nm.

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