Photometric study of NGC 2023 in the 3500 A to 10000 A region - Confirmation of a near-IR emission process in reflection nebulae

1984 ◽  
Vol 281 ◽  
pp. 708 ◽  
Author(s):  
A. N. Witt ◽  
R. E. Schild ◽  
J. B. Kraiman
Keyword(s):  
Photometric Study ◽  
Emission Process ◽  
Near Ir ◽  
Ir Emission ◽  
Reflection Nebulae

Cholesterol Hydroperoxides Generate Singlet Molecular Oxygen [O2(1Δg)]: Near-IR Emission,18O-Labeled Hydroperoxides, and Mass Spectrometry

2011 ◽  
Vol 24 (6) ◽  
pp. 887-895 ◽  
Author(s):  
Miriam Uemi ◽  
Graziella E. Ronsein ◽  
Fernanda M. Prado ◽  
Flávia D. Motta ◽  
Sayuri Miyamoto ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Molecular Oxygen ◽  
Singlet Molecular Oxygen ◽  
Near Ir ◽  
Ir Emission

Near-IR emission from holmium–ytterbium co-doped alkali bismuth gallate and fluorophosphate fiber glass preforms

2009 ◽  
Vol 473 (1-2) ◽  
pp. 500-504 ◽  
Author(s):  
M. Alejandrina Martínez Gámez ◽  
A.V. Kir’yanov ◽  
J.L. Lucio M. ◽  
C. Wiechers ◽  
G.A. Kumar
Keyword(s):  
Fiber Glass ◽  
Near Ir ◽  
Ir Emission ◽  
Co Doped

Near-IR Emission and upconversion luminescent properties of Tb3+/Yb3+ Co-doped HfO2/SiO2 nanoparticles

2021 ◽  
Author(s):  
Vicente Vargas ◽  
Anastasiya Sedova ◽  
Jesús Uriel Balderas ◽  
S. Carmona-Tellez ◽  
Iván Merlin ◽  
...  
Keyword(s):  
Luminescent Properties ◽  
Sio2 Nanoparticles ◽  
Near Ir ◽  
Ir Emission ◽  
Co Doped

scholarly journals Spectrally resolved confocal microscopy using lanthanide centred near-IR emission

2015 ◽  
Vol 51 (12) ◽  
pp. 2372-2375 ◽  
Author(s):  
Zhiyu Liao ◽  
Manuel Tropiano ◽  
Konstantins Mantulnikovs ◽  
Stephen Faulkner ◽  
Tom Vosch ◽  
...  
Keyword(s):  
Confocal Microscopy ◽  
Silica Particles ◽  
Near Ir ◽  
Nir Imaging ◽  
Spectrally Resolved ◽  
Ir Emission

NIR imaging of lanthanide-coated silica particles where the photons used to generate the image unambiguously can be assigned to arise from lanthanide centred emission.

scholarly journals The Dust in the Hydrogen-Poor Ejecta of Abell 30

1993 ◽  
Vol 155 ◽  
pp. 386-386
Author(s):  
J.P. Harrington ◽  
K.J. Borkowski ◽  
W.P. Blair ◽  
J. Bregman
Keyword(s):  
High Resolution ◽  
Amorphous Carbon ◽  
Ir Spectrum ◽  
Stellar Wind ◽  
Thermal Emission ◽  
Central Star ◽  
Near Ir ◽  
High Resolution Images ◽  
Small Grains ◽  
Ir Emission

High-resolution images in [O III] λ5007 of the hydrogen-poor knots of Abell 30 reveal comet-like structures which may be indicative of interaction with the stellar wind. In the near IR, new, higher-resolution, K-band images show an equatorial ring of hot dust that corresponds closely to optical knots 2 and 4 of Jacoby and Ford, while their polar knots 1 and 3 show no comparable IR emission. Both the thermal IR emission and the heavy internal extinction of the central star demands an extremely dusty ejecta. Greenstein showed that the UV extinction curve is fit by amorphous carbon. Our comprehensive dust models consider both the UV extinction and the IR emission from a population of carbon grains. The thermal emission from larger grains produces the far IR emission, while the stochastic heating of very small grains to high temperatures is essential to explain the near IR flux. We are able to reproduce the shape of the near IR spectrum with an a−3.0 distribution of grain radii which extends down to a minimum grain radius of 8 Å.

Near-IR emission of Nd(III) encaged in nanosized zeolites

2004 ◽  
Vol 30 (2) ◽  
pp. 191-205 ◽  
Author(s):  
Munenori Ryo ◽  
Yuji Wada ◽  
Tatsuya Okubo ◽  
Shozo Yanagida
Keyword(s):  
Near Ir ◽  
Ir Emission ◽  
Nanosized Zeolites

scholarly journals Multifrequency Variability of AGN's: Continuum Variations from the Near IR to the X-rays

1994 ◽  
Vol 159 ◽  
pp. 131-143
Author(s):  
J. Clavel
Keyword(s):  
Active Galactic Nuclei ◽  
Temporal Evolution ◽  
Line Emission ◽  
Galactic Nuclei ◽  
The Other ◽  
X Rays ◽  
Optical Telescope ◽  
Emission Process ◽  
Near Ir ◽  
The Continuum

Because they emit copiously over more than 10 decades in frequency, Active Galactic Nuclei (AGN) cannot be understood without the help of multiwavelength observations. On the other hand, variability monitoring has also proven to be invaluable in understanding the continuum and line emission process as well as the geometry of the innermost regions in these objects. Indeed, at the heart of AGN's lies an object which is so compact that the only way to probe its structure is the study of the temporal evolution of its spectrum. The equivalent resolution which can be achieved in this way is of the order of 10 microarcsecs, far beyond the capability of any UV or optical telescope.

RECENT PROGRESS IN ERBIUM(III)-CORED COMPLEXES BASED ON DENDRITIC LIGANDS FOR ADVANCED PHOTONICS APPLICATIONS

2006 ◽  
Vol 15 (03) ◽  
pp. 369-379 ◽  
Author(s):  
NAM SEOB BAEK ◽  
YONG HEE KIM ◽  
HWAN KYU KIM
Keyword(s):  
Fluorescence Intensity ◽  
Near Infrared ◽  
Aryl Ether ◽  
Strong Decrease ◽  
Efficient Energy Transfer ◽  
Site Isolation ◽  
Near Ir ◽  
Generation Number ◽  
Photo Stability ◽  
Ir Emission

We present that the stable and inert Er(III) -encapsulated complexes based on naphthalene and anthracene ligands bearing a Fréchet aryl-ether dendron exhibit much stronger near-IR emission bands bands at 1530 nm, originated from the 4f–4f electronic transition of the first excited state (4 I 13/2) to the ground state (4 I 15/2) of the partially-filled 4f shell. A strong decrease in the fluorescence of G n-aryl ether dendron (n = 0 or 2) is accompanied by strongly increasing the fluorescence intensity of the luminescent anthracene or naphthalene ligand with the generation number of the dendrons. The strong decrease of fluorescence intensity of luminescent ligand such as naphthalene and anthracene units is accompanied by strongly increasing the near infrared (IR) emission of the Er 3+ ions in Er(III) -encapsulated complexes. It could be attributed to the efficient energy transfer process occurring between the aryl-ether dendron and anthracene moiety as well as between dendritic anthracene ligand and Er 3+ ion. Thus, the emission intensity of the lanthanide complexes, upon photoexcitation of aryl-ether dendrons at 290 nm, was dramatically enhanced with an increase in the generation number n of dendrons, due to the site-isolation and light-harvesting effects. In addition, Er 3+-[ G 2- An ]3(terpy) exhibits the stronger PL intensity than Er 3+-[ G 2- Na ]3(terpy)) by 2.5 times, upon photoexcitation of aryl-ether dendrons at 290 nm. It may be due to the fact that the anthracene ligand in Er 3+-[ G 2- An ]3(terpy)) has higher spectral overlap integral (J) value than the naphthalene ligand in Er 3+-[ G 2- Na ]3(terpy) by 1.5 times. Surprisingly, all Er(III) -cored dendrimer complexes have excellent thermal- and photo-stability as well as good solubility.

Intense Near-IR Emission from Nanoscale Lanthanoid Fluoride Clusters

2008 ◽  
Vol 120 (32) ◽  
pp. 6138-6140 ◽  
Author(s):  
Michael Romanelli ◽  
G. Ajith Kumar ◽  
Thomas J. Emge ◽  
Richard E. Riman ◽  
John G. Brennan
Keyword(s):  
Near Ir ◽  
Ir Emission

Preparation and Characterization of the Active Layer for an Led Based on Oxidized Porous Silicon

1996 ◽  
Vol 452 ◽  
Author(s):  
L. Tsybeskov ◽  
K. D. Hiirschman ◽  
L. F. Moore ◽  
P. M. Fauchet ◽  
P. D. J. Calcott
Keyword(s):  
Porous Silicon ◽  
Carrier Transport ◽  
Strong Dependence ◽  
Band Emission ◽  
Annealing Conditions ◽  
Near Ir ◽  
Spectral Peaks ◽  
Oxidized Porous Silicon ◽  
Ir Emission

AbstractWe have studied the photoluminescence (PL) in oxidized porous silicon (PSi), prepared from anodized crystalline Si followed by annealing at temperatures ranging from 700 to 1000°C. It has been found that two PL bands with spectral peaks at 1.6 e V (near-IR band) and near 2 eV (red band) exist with a strong dependence on preparation (annealing) conditions. Recent experimental results show a correlation between the intensity of the near-IR band and the level of leakage current in the diode-like structure. The suppression of the near-IR emission results in improved carrier transport, and the enhancement of the red band emission maximizes the electroluminescence (EL) efficiency. The PL study of thermally oxidized PSi indicates different recombination mechanisms. The red PL band is associated with a mechanism similar to band-tail-recombination within the quasi-bandgap of Si nanograins, whereas the near infra-red PL is associated with recombination via defect centers. These mechanisms will be discussed.

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