Significant Variations in the Luminescence of Samarium(II) Doped Strontium and Barium Octaborate as a Function of Excitation Wavelength and Sample Temperature

2018 ◽  
Vol 73 (5) ◽  
pp. 550-555 ◽  
Author(s):  
Shakeena L. Walker ◽  
Christopher H. Drozdowski ◽  
Jafar Gharavi-Naeini ◽  
Nathan A. Stump
Keyword(s):  
Temperature Dependence ◽  
Significant Variation ◽  
Emission Spectra ◽  
Sample Temperature ◽  
Excitation Wavelength ◽  
Strong Temperature Dependence ◽  
Strontium Borate

The emission features characteristic of divalent samarium formed in samarium-doped barium octaborate (BaB8O13) and strontium borate (Sr2B16O26) have been studied as a function of excitation wavelength and sample temperature. The emission spectra of divalent samarium in both materials exhibit a surprisingly strong temperature dependence. When divalent samarium is doped into BaB8O13, changes in excitation wavelength and sample temperature both result in significant variations in the emission features associated with the material. It is therefore hypothesized that the variation arises primarily from selected excitation of individual samarium sites within the BaB8O13 matrix. The emission features characteristic of divalent samarium in Sr2B16O26, also exhibited significant variation as the sample temperature was lowered, but this variation was irrespective of the excitation wavelength. This appears to indicate dependence solely on competition between de-excitation pathways.

Temperature Dependence of the Critical Electron Dose for Fatty Acid Monolayers

1982 ◽  
Vol 40 ◽  
pp. 78-79
Author(s):  
Kenneth H. Downing ◽  
Robert M. Glaeser
Keyword(s):  
Electron Beam ◽  
Fatty Acid ◽  
Inelastic Scattering ◽  
Temperature Dependence ◽  
Structural Damage ◽  
Direct Result ◽  
Second Step ◽  
Strong Temperature Dependence ◽  
Electron Dose ◽  
Covalent Bonds

The structural damage of molecules irradiated by electrons is generally considered to occur in two steps. The direct result of inelastic scattering events is the disruption of covalent bonds. Following changes in bond structure, movement of the constituent atoms produces permanent distortions of the molecules. Since at least the second step should show a strong temperature dependence, it was to be expected that cooling a specimen should extend its lifetime in the electron beam. This result has been found in a large number of experiments, but the degree to which cooling the specimen enhances its resistance to radiation damage has been found to vary widely with specimen types.

Preparation and Properties of La2O3-CaO-P2O5 Glasses Doped with Eu3+ Ions

2016 ◽  
Vol 675-676 ◽  
pp. 376-379 ◽  
Author(s):  
Narun Luewarasirikul ◽  
Piyachat Meejitpaisan ◽  
Jakrapong Kaewkhao
Keyword(s):  
Calcium Phosphate ◽  
Molar Volume ◽  
Absorption Spectra ◽  
Room Temperature ◽  
Emission Spectra ◽  
Phosphate Glasses ◽  
Excitation Wavelength ◽  
Melt Quenching ◽  
Volume Measurements ◽  
Doped Glasses

Lanthanum calcium phosphate glasses doped with Eu3+ ions in compositions 20La2O3:10CaO:(70-x)P2O5:xEu2O3 (where x = 0.05, 0.10, 0.50 and 1.50 mol%) were prepared by melt-quenching technique. The density and molar volume measurements were carried out at room temperature. The absorption spectra were investigated in the UV-Vis-NIR region from 200 to 2500 nm. The emission spectra of Eu3+-doped glasses centered at 590 nm (5D0→7F1), 612 nm (5D0→7F2), 652 nm (5D0→7F3) and 699 nm (5D0→7F4) have been observed with 393 nm excitation wavelength.

scholarly journals Temperature-Driven Spin Reorientation Transition in CoPt/AlN Multilayer Films

2012 ◽  
Vol 2012 ◽  
pp. 1-7
Author(s):  
Wupeng Cai ◽  
Shinji Muraishi ◽  
Ji Shi ◽  
Yoshio Nakamura ◽  
Wei Liu ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Mean Field ◽  
Multilayer Films ◽  
Spin Reorientation ◽  
Strong Temperature Dependence ◽  
Mean Field Model ◽  
Spin Reorientation Transition ◽  
Magnetoelastic Effect ◽  
Out Of Plane ◽  
Interface Anisotropy

Spin reorientation transition phenomena from out-of-plane to in-plane direction with increasing temperature are observed for the 500°C annealed CoPt/AlN multilayer films with different CoPt layer thicknesses. CoPt-AlN interface and volume anisotropy contributions, favoring out-of-plane and in-plane magnetization, respectively, are separately determined at various temperatures. Interface anisotropy exhibits much stronger temperature dependence than volume contribution, hence the temperature-driven spin reorientation transition occurs. Interface anisotropy in this work consists of Néel interface anisotropy and magnetoelastic effect. Magnetoelastic effect degrades rapidly and changes its sign from positive to negative above 200°C, because of the involvement of stress state in CoPt films with temperature. By contrast, Néel interface anisotropy decays slowly, estimated from a Néel mean field model. Thus, the strong temperature dependence of CoPt-AlN interface anisotropy is dominated by the change of magnetoelastic effect.

The Temperature Dependence of Emission Spectra in α-9, 10-Dichloroanthracene

1983 ◽  
Vol 117 (2) ◽  
pp. K95-K97 ◽  
Author(s):  
V. Železný ◽  
L. Jastrabík ◽  
L. Dobiášová
Keyword(s):  
Temperature Dependence ◽  
Emission Spectra

Multiple excitation wavelength fluorescence emission spectra technique for discrimination of phytoplankton

2010 ◽  
Vol 9 (1) ◽  
pp. 16-24 ◽  
Author(s):  
Xupeng Hu ◽  
Rongguo Su ◽  
Fang Zhang ◽  
Xiulin Wang ◽  
Hongtao Wang ◽  
...  
Keyword(s):  
Fluorescence Emission ◽  
Emission Spectra ◽  
Excitation Wavelength ◽  
Fluorescence Emission Spectra

scholarly journals Thermochromism of Highly Luminescent Photopolymer Flexible Films Based On Eu (III) Salts Confined in Polysulfone

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5394
Author(s):  
Mani Outis ◽  
João Paulo Leal ◽  
Maria Helena Casimiro ◽  
Bernardo Monteiro ◽  
Cláudia Cristina Lage Pereira
Keyword(s):  
Thermal Stability ◽  
Ionic Liquid ◽  
Melting Point ◽  
Quantum Yield ◽  
Thermal Behavior ◽  
Temperature Dependence ◽  
Strong Temperature Dependence ◽  
Host Matrix ◽  
Flexible Films ◽  
First Time

Here we discuss the influence of two different cations on the emissive properties of the highly emissive [Eu(fod)4]− anion. The studied Eu(III) salts were [C16Pyr][Eu(fod)4] (1), and the previously reported [Chol][Eu(fod)4]. C16Pyr stands for N-cetylpyridinium, Chol for cholinium and fod for 1,1,1,2,2,3,3-heptafluoro-7,7-dimethyloctane-4,6-dionate. 1 is classified as ionic liquid, with melting point close to 60 °C, and presented a luminescence quantum yield of (ϕ) 100%. Ultrabright emissive photopolymers were obtained for the first time using polysulfone as the host matrix. The films were prepared with incorporation of 10% (w/w) of 1 and [Chol][Eu(fod)4] in the polymeric matrix, which improved its thermal stability. Additionally, the luminescence of CholEu(fod)4/PSU presented a strong temperature dependence with a ratiometric thermal behavior.

Sample temperature dependence of plasma desorption mass spectra of biomolecules

1992 ◽  
Vol 64 (23) ◽  
pp. 2977-2980 ◽  
Author(s):  
D. D. N. Barlo Daya ◽  
P. Demirev ◽  
P. Haakansson ◽  
J. Kjellberg ◽  
B. U. R. Sundqvist
Keyword(s):  
Temperature Dependence ◽  
Mass Spectra ◽  
Sample Temperature ◽  
Plasma Desorption
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