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Riya Dey et al.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, 99, 288-291 (2012-10-23)
The Y(2)O(3) phosphor powder codoped with Nd(3+):Yb(3+) ions have been synthesized through optimized combustion route. Crystalline structures of the prepared samples have been investigated by powder X-ray diffraction technique. Efficient upconversion emission in the green region upon 980 nm NIR
Tao Zhang et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 19(2), 739-748 (2012-11-21)
Based on a donor-acceptor framework, several conjugates have been designed and prepared in which an electron-donor moiety, ytterbium(III) porphyrinate (YbPor), was linked through an ethynyl bridge to an electron-acceptor moiety, boron dipyrromethene (BODIPY). Photoluminescence studies demonstrated efficient energy transfer from
Jinkang Lim et al.
Optics express, 21(4), 4531-4538 (2013-03-14)
Laser frequency combs are normally based on mode-locked oscillators emitting ultrashort pulses of ~100-fs or shorter. In this paper, we present a self-referenced frequency comb based on a narrowband (5-nm bandwidth corresponding to 415-fs transform-limited pulses) Yb-fiber oscillator with a
Li Li et al.
Journal of nanoscience and nanotechnology, 14(6), 4313-4319 (2014-04-18)
Lutetium oxide nanocrystals codoped with Tm3+ and Yb3+ have been successfully synthesized via adjusting the pH values of the precursor solution in a hydrothermal method followed by a subsequent calcination process. The samples were systematically characterized by X-ray diffraction, field-emission
Liming Zhang et al.
Journal of nanoscience and nanotechnology, 14(6), 4710-4713 (2014-04-18)
LiYbF4:Yb, Er nanoparticles have been successfully synthesized by thermal decomposition of multiple trifluoroacetic acid salts. The SEM and TEM results show the size of the LiYF4:Yb, Er nanoparticles is about 100 nm in diagonal line, and the morphology of the
Qingbo Xiao et al.
Chemical communications (Cambridge, England), 49(15), 1527-1529 (2013-01-17)
By utilizing multicolor upconversion luminescence of rare earth-doped nanophosphors (UCNPs), NIR-light-activated photopolymerization and controlled drug delivery is achieved for PEGDA hydrogels. The loading capacity of zinc(II) phthalocyanine reaches 12.3% into UCNPs-PEGDA hybrid microspheres.
Hongqi Chen et al.
Biosensors & bioelectronics, 48, 19-25 (2013-05-04)
In this work, we design a FRET system for sensitive and selective determination of thrombin in red region, in which NaYF₄:Yb,Er upconversion nanoparticles (UCNPs) act as donor and gold nanorods (Au NRs) act as acceptor. NaYF₄:Yb,Er UCNPs with a strong
Alexandra Foucault-Collet et al.
Proceedings of the National Academy of Sciences of the United States of America, 110(43), 17199-17204 (2013-10-11)
We have created unique near-infrared (NIR)-emitting nanoscale metal-organic frameworks (nano-MOFs) incorporating a high density of Yb(3+) lanthanide cations and sensitizers derived from phenylene. We establish here that these nano-MOFs can be incorporated into living cells for NIR imaging. Specifically, we
Wenbin Niu et al.
Nanoscale, 5(17), 8164-8171 (2013-07-28)
The ability to manipulate the upconversion luminescence of lanthanide-ion doped fluoride upconversion nanoparticles (UCNPs) is particularly important and highly desired due to their wide applications in color displays, multiplexing bioassays and multicolor imaging. Here, we developed a strategy for simultaneously
Lu Li et al.
Nanoscale, 5(6), 2249-2253 (2013-02-12)
Multifunctional fluorescent-magnetic pH-responsive eccentric-(concentric-Fe3O4@SiO2)@polyacrylic acid core-double shell nanocomposites (NCs) have been prepared for simultaneous cell imaging and pH-responsive drug delivery. To confirm the universality of the synthetic concept, the synthetic strategy was also extended to fabricate monodisperse eccentric-(concentric-NaYF4:Yb/Er/Gd@SiO2)@polyacrylic acid core-double
Junghan Lee et al.
Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 54(1), 96-103 (2012-12-13)
Multimodal nanoparticles have been extensively studied for target-specific imaging and therapy of various diseases, including cancer. In this study, radiolabeled arginine-glycine-aspartic acid (RGD)-functionalized Er(3+)/Yb(3+) co-doped NaGdF(4) upconversion nanophosphors (UCNPs) were synthesized and evaluated as a multimodal PET/MR/optical probe with tumor
Zhen Liu et al.
Biomaterials, 34(6), 1712-1721 (2012-12-04)
Due to their unique electric, magnetic, and optical properties, engineered nanostructures have been applied to provide diagnostic, therapeutic, as well as prognostic information about the status of disease. In this study, we report a multifunctional nanoprobe based on PEGylated Gd(2)O(3):Yb(3+)
Dangli Gao et al.
Dalton transactions (Cambridge, England : 2003), 42(5), 1834-1841 (2012-11-21)
An innovative route to tune upconversion (UC) emission in β-NaYF(4):Yb(3+)/Tm(3+) nanorods through codoping a third rare-earth ion upon continuous wave excitation near 976 nm is reported. The dependence of UC emission on codopant concentration and environment temperature shows that tailored
Jin, W-S. et al.
Chemical Communications (Cambridge, England), 1101-1101 (1998)
Zhijiang Wang et al.
Talanta, 114, 124-130 (2013-08-21)
Fluorescent detection is an attractive method for the detection of toxic chemicals. However, most chemosensors that are currently utilized in fluorescent detection are based on organic dyes or quantum dots, which suffer from instability, high background noise and interference from
Miftar Ganija et al.
Optics express, 21(6), 6973-6978 (2013-04-03)
A cryogenic slab laser that is suitable for scaling to high power, while taking full advantage of the improved thermo-optical and thermo-mechanical properties of Yb:YAG at cryogenic temperatures is described. The laser uses a conduction cooled, end pumped, zigzag slab
S Rydberg et al.
Optics express, 21(6), 6681-6688 (2013-04-03)
In this work we present experimental evidence that the valence instability of the ytterbium ion play a key role for the observed photodarkening mechanism in Yb-doped fiber lasers. Luminescence and excitation spectroscopy performed on UV irradiated Yb/Al doped silica glass
Charles W Rudy et al.
Optics express, 20(25), 27589-27595 (2012-12-25)
We report generation of 48 fs pulses at a center wavelength of 2070 nm using a degenerate optical parametric oscillator (OPO) synchronously-pumped with a commercially available 36-MHz, femtosecond, mode-locked, Yb-doped fiber laser. The spectral bandwidth of the output is ~137
Luc Beaulieu et al.
Medical physics, 39(10), 6208-6236 (2012-10-09)
The charge of Task Group 186 (TG-186) is to provide guidance for early adopters of model-based dose calculation algorithms (MBDCAs) for brachytherapy (BT) dose calculations to ensure practice uniformity. Contrary to external beam radiotherapy, heterogeneity correction algorithms have only recently
Marcus L Cole et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 19(4), 1410-1420 (2012-12-04)
New reactive, divalent lanthanoid formamidinates [Yb(Form)(2)(thf)(2)] (Form=[RNCHNR]; R=o-MeC(6)H(4) (o-TolForm; 1), 2,6-Me(2)C(6)H(3) (XylForm; 2), 2,4,6-Me(3)C(6)H(2) (MesForm; 3), 2,6-Et(2)C(6)H(3) (EtForm; 4), o-PhC(6)H(4) (o-PhPhForm; 5), 2,6-iPr(2)C(6)H(3) (DippForm; 6), o-HC(6)F(4) (TFForm; 7)) and [Eu(DippForm)(2)(thf)(2)] (8) have been prepared by redox transmetallation/protolysis reactions between an
A E Bednyakova et al.
Optics express, 21(7), 8177-8182 (2013-04-11)
We present direct real-time experimental measurements and numerical modeling of temporal and statistical properties for the Ytterbium-doped fiber laser with spectral bandwidth of ~2 GHz. The obtained results demonstrate nearly exponential probability density function for intensity fluctuations. A significant decrease
Sylvia Jetschke et al.
Optics express, 21(6), 7590-7598 (2013-04-03)
In contrast to Yb/Al-doped fibers, the influence of very low Tm(2)O(3) concentrations (≥ 0.1 mol-ppm) on photodarkening (PD) is clearly detectable in Yb/P-doped fibers that are known to show little degradation effects. For Tm(2)O(3) additions of more than 50 mol-ppm
Ying Xie et al.
Journal of nanoscience and nanotechnology, 14(6), 4486-4489 (2014-04-18)
Eu3+ and Yb3+ codoped Y2O3 phosphors were synthesized by the sol-gel method. The phosphors possess absorption in the region of 300-550 nm, exhibiting an intense NIR emission of Yb3+ around 1000 nm, which is suitable for matching the maximum spectral
Wei Gao et al.
Journal of nanoscience and nanotechnology, 14(6), 4308-4312 (2014-04-18)
Pr3+/Yb3+ co-doped hexagonal NaYF4(beta-NaYF4) microprisms were synthesized by the hydrothermal method, and ethylenediaminetetraacetic acid (EDTA) was introduced to control the size of the microcrystal samples. Bright upconverted fluorescence emission was observed when the samples were excited with an infrared (IR)
Yi Tong et al.
Scientific reports, 5, 16761-16761 (2015-11-17)
The advent of flexible optoelectronic devices has accelerated the development of semiconducting polymeric materials. We seek to replace conventional expensive semiconducting photodetector materials with our cost-effective composite system. We demonstrate in this work the successful fabrication of a photoconductive composite
Hui Chen et al.
Analytical chemistry, 84(20), 8871-8879 (2012-10-09)
The ultraweak chemiluminescence (CL) from the reaction of hydrogen peroxide and carbonate is strongly enhanced by the branched NaYF(4):Yb(3+)/Er(3+) nanoparticle (NP) in the presence of aqueous ammonia. It was explained that ammonia catalyzes the decomposition of peroxymonocarbonate, which is the
Sethuraman Gayathri et al.
Carbohydrate polymers, 121, 302-308 (2015-02-11)
In this study, chitosan functionalized LaF3:Yb,Er upconverting nanotransducers (UCNTs) with controlled size and shape have been successfully synthesized by a facile one pot precipitation method. The chitosan encapsulated UCNTs show bright upconversion fluorescence upon excitation with 974 nm NIR region.
Thorben Rinkel et al.
Nanoscale, 6(23), 14523-14530 (2014-10-28)
We have studied the growth behaviour of sub-10 nm NaYF₄ upconversion nanocrystals of the hexagonal β-phase and the cubic α-phase. Ostwald-ripening of such particles in oleic acid/octadecene solvent results in broadening of the particle size distribution if the colloid contains
Daiki Goto et al.
Analytical sciences : the international journal of the Japan Society for Analytical Chemistry, 31(11), 1143-1149 (2015-11-13)
It is difficult to control the electrophoretic mobility in order to obtain high resolution among saccharides in complex samples. We report herein on a new affinity capillary electrophoresis (ACE) method for an anionic monosaccharide, N-acetylneuraminic acid (Neu5Ac), which is important
Lu Zhang et al.
Chemical communications (Cambridge, England), 48(91), 11238-11240 (2012-10-13)
Multifunctional magnetic/upconversion luminescent mesoparticles, consisting of a Fe(3)O(4) nanoparticle core and a LaF(3):Yb(3+), Er(3+) nanocrystal shell, have been developed using a facile co-precipitation approach. Owing to their excellent superparamagnetic properties, superior T(2)-enhanced magnetic resonance effect and strong upconversion emissions, the
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