Optical absorption and photoluminescence properties of Nd3+ doped mixed alkali phosphate glasses-spectroscopic investigations.

PubMed

Ratnakaram, Y C; Srihari, N V; Kumar, A Vijaya; Naidu, D Thirupathi; Chakradhar, R P S

2009-02-01

Spectroscopic investigations were performed on 68NH(4)H(2)PO(4).xLi(2)CO(3)(30-x)K(2)CO(3) and 68NH(4)H(2)PO(4).xNa(2)CO(3)(30-x)K(2)CO(3) (where x=5, 10, 15, 20 and 25) glasses containing 2 mol% Nd(2)O(3). Various spectroscopic parameters (Racah (E(1), E(2), E(3)), spin-orbit (xi(4f)) and configuration interaction (alpha)) are reported. Judd-Ofelt intensity parameters (Omega(2), Omega(4), Omega(6)) are calculated for Nd(3+) doped two mixed alkali phosphate glass matrices. From the magnitude of Judd-Ofelt parameters, covalency is studied as a function of x in the glass matrix. Using Judd-Ofelt intensity parameters, total radiative transition probabilities (A(T)), radiative lifetimes (tau(R)), branching ratios (beta) and integrated absorption cross sections (Sigma) have been computed for certain excited states of Nd(3+) in these mixed alkali phosphate glasses. Emission cross sections (sigma(P)) are calculated for the two transitions, (4)G(7/2)-->(4)I(11/2) and (4)G(7/2)-->(4)I(13/2) of Nd(3+) in these mixed alkali phosphate glasses. Optical band gaps (E(opt)) for direct and indirect transitions are reported.

Mid-infrared emission and Judd-Ofelt analysis of Dy3+-doped infrared Ga-Sb-S and Ga-Sb-S-PbI2 chalcohalide glasses

NASA Astrophysics Data System (ADS)

Guo, Jixiao; Jiao, Qing; He, Xiaolong; Guo, Hansong; Tong, Jianghao; Zhang, Zhihang; Jiang, Fuchao; Wang, Guoxiang

2018-03-01

Dy3+-doped Ga-Sb-S and Ga-Sb-S-PbI2 chalcohalide glasses were prepared by traditional melt quenching method. The effect of halide PbI2 on the physical and optical properties of Dy3+ ions was investigated. The density and ionic concentration of the host sample increased with the introduction of PbI2 halides, whereas the refractive index at 1.55 μm decreased. The Judd-Ofelt parameters showed that Ω2 increased in PbI2-modified glass, whereas the Ω6 value showed the opposite tendency. Infrared emission spectrum also showed that the intensity increased with PbI2 addition, and considerable enhancement at 2.8 μm was observed in the mid-infrared region. The halide PbI2 promoted the reduction of phonon energy of the host and the improvement of the laser pump efficiency, which led to the construction of optimized infrared glass materials for optical applications.

Synthesis and near-infrared fluorescence of K5NdLi2F10 nanocrystals and their dispersion with high doping concentration and long lifetime

NASA Astrophysics Data System (ADS)

Duan, Weikuan; Zhang, Yanyan; Wang, Zhongyue; Jiang, Jingyi; Liang, Chen; Wei, Wei

2014-05-01

K5NdLi2F10 nanocrystals were synthesized by a novel synthetic route in the liquid phase, which could improve the morphology and reduce the size effectively, for the first time. The luminescence intensities of the K5NdLi2F10 nanocrystals and their dispersion in polyethylene glycol 400 (PEG-400) approximate to that of neodymium doped phosphate glass (3 mol%), while the lifetimes of the nanocrystals alone and when dispersed with Nd3+ ions (1 × 1020 cm-3) are 303.4 μs and 174.6 μs respectively. Based on the Judd-Ofelt analysis, the emission quantum yield of the dispersion reaches 39.57%. In all, the K5NdLi2F10 nanocrystals and their dispersion have promising applications as liquid laser materials and biological fluorescent markers.K5NdLi2F10 nanocrystals were synthesized by a novel synthetic route in the liquid phase, which could improve the morphology and reduce the size effectively, for the first time. The luminescence intensities of the K5NdLi2F10 nanocrystals and their dispersion in polyethylene glycol 400 (PEG-400) approximate to that of neodymium doped phosphate glass (3 mol%), while the lifetimes of the nanocrystals alone and when dispersed with Nd3+ ions (1 × 1020 cm-3) are 303.4 μs and 174.6 μs respectively. Based on the Judd-Ofelt analysis, the emission quantum yield of the dispersion reaches 39.57%. In all, the K5NdLi2F10 nanocrystals and their dispersion have promising applications as liquid laser materials and biological fluorescent markers. Electronic supplementary information (ESI) available: Fitting curve of refractive index and detailed contents of Judd-Ofelt analysis. See DOI: 10.1039/c3nr06825k

Physical, structural and spectroscopic investigations of Sm3+ doped ZnO mixed alkali borate glass

NASA Astrophysics Data System (ADS)

Sailaja, B.; Joyce Stella, R.; Thirumala Rao, G.; Jaya Raja, B.; Pushpa Manjari, V.; Ravikumar, R. V. S. S. N.

2015-09-01

Glass of 20ZnO-15 Li2O-15 Na2O-49.9 B2O3 doped with 0.1 mol% of Sm3+ (ZLNB) was prepared by the melt quenching technique. Physical properties were studied and analysed. The XRD studies confirm the amorphous nature of sample. The FT-IR spectral investigation discloses the BO3, BO4 groups, H and OH bonds. Optical absorption and emission spectra were recorded and characterized. Judd-Ofelt theory was applied to f ↔ f transitions to evaluate Judd-Ofelt intensity parameters (Ωλ). The oscillator strengths and bonding parameters were determined from absorption spectra. The trend observed was Ω4 > Ω6 > Ω2. High value of Ω4 reveals higher rigidity and covalency around the Sm3+ ion. Low value of Ω2 implies ionic nature of ligands and site symmetry around Sm3+ ion. luminescence data and Judd-Ofelt parameters Ωλ (λ = 2, 4, and 6) were used to evaluate various radiative probabilities like spontaneous radiative emission probabilities (AR), radiative lifetime (τR) and branching ratios (βR) stimulated emission cross section (σe) and CIE colour coordinates were measured, CCT temperature evaluated and the values were used to ascertain potential laser transitions at the optimum mixed alkali effect observed for the glass sample prepared. The preparedness of the material as the efficient laser active material is examined.

Investigation of Tm3+/Yb3+ co-doped germanate-tellurite glasses for efficient 2 µm mid-infrared laser materials

NASA Astrophysics Data System (ADS)

Dou, Aoju; Shen, Lingling; Wang, Ning; Cai, Yangjian; Cai, Muzhi; Guo, Yanyan; Huang, Feifei; Tian, Ying; Xu, Shiqing; Zhang, Junjie

2018-05-01

The Tm3+/Yb3+ co-doped germanate-tellurite glasses with good thermal properties were prepared. Based on the absorption spectra and the Judd-Ofelt theory, the J-O intensity parameters (Ω t ), radiative transition probability (276.78 s- 1), fluorescence lifetime (3.89 ms), absorption and emission cross sections ({σ e} = 1.35 × 10- 20 cm2) were calculated. The 2 µm mid-infrared emission resulting from the 3F4→3H6 transition of Tm3+ sensitized by Yb3+ was observed pumped by 980 nm LD. Besides, the energy transfer mechanism between Yb3+ and Tm3+ was thoroughly discussed. The measured 2 µm emission lifetime of Tm3+/Yb3+ co-doped glass can reach as high as 2.38 ms. The above results showed that Tm3+/Yb3+ co-doping glass could be expected to be a promising material to achieve high efficient 2 µm lasing with a 980 nm LD pumping.

Spectroscopic attributes of Sm3+ doped magnesium zinc sulfophosphate glass: Effects of silver nanoparticles inclusion

NASA Astrophysics Data System (ADS)

Ahmadi, F.; Hussin, R.; Ghoshal, S. K.

2017-11-01

We report the modified optical properties of Sm3+ doped magnesium zinc sulfophosphate glass system with silver nanoparticles (Ag NPs) inclusion. Three glass samples were prepared using melt quenching method and characterized. TEM images revealed the nucleation of Ag NPs with average diameter ≈12.50 nm. The UV-Vis-NIR spectra showed thirteen absorption bands. The surface plasmon resonance (SPR) band of Ag NPs was manifested at 446 nm. FTIR spectra disclosed the bonding vibrations for P-O bonds, P-O-P linkages, and PO2 units. Ag NPs concentration dependent bonding parameters and Judd-Ofelt (JO) intensity parameters were calculated. The JO parameter Ω2 was reduced with the increase of Ag NPs contents, indicating the ionicity and symmetry enhancement between Sm3+ ions with their surrounding ligands. The emission spectra of all samples under the excitation wavelength of 402 nm exhibited four significant peaks centered at 562, 599, 644 and 702 nm which are allocated to 4G5/2 →6H5/2, 6H7/2, 6H9/2 and 6H11/2 transitions, respectively. Inclusion of Ag NPs was discerned to augment the luminescence intensity by a factor of two, which was majorly ascribed to the local field effect of Ag NPs and subsequent energy transfer from the NPs to Sm3+ ions.

Red light emission from europium doped zinc sodium bismuth borate glasses

NASA Astrophysics Data System (ADS)

Hegde, Vinod; Viswanath, C. S. Dwaraka; Upadhyaya, Vyasa; Mahato, K. K.; Kamath, Sudha D.

2017-12-01

Zinc sodium bismuth borate (ZNBB) glasses doped with different concentrations of europium were prepared by conventional melt quenching method and characterized through the measurements of density, refractive index, X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectra, optical absorption, luminescence and radiative lifetimes. FTIR spectra showed seven characteristic peaks of bismuth and borate functional groups in the range of 400-1600 cm-1. The optical band gap and bonding parameters have been calculated from absorption spectra. Photoluminescence spectra recorded in the visible region with 394 nm excitation are used to calculate the Judd-Ofelt (JO) intensity parameters (Ω2 and Ω4). The JO intensity parameters have been used to calculate the radiative parameters such as branching ratio (β), stimulated emission cross-section (σse), transition probability (A) for the fluorescent level of 5D0→7F2. Decay rates through single exponential are used to calculate the lifetime (τm) of the meta-stable state 5D0 of (Eu3+ ion) these glasses. The radiative parameters measured for all these glasses show 0.7 mol% europium doped zinc sodium bismuth borate glass 5D0→7F2 transition has the potential for red laser applications. The quality of the colour emitted by the present glasses are estimated quantitatively by CIE chromaticity coordinates, which confirms the suitability of these glasses as a red emitting material for field emission technologies and LEDs.

Spectroscopic analysis of a novel Nd3+-activated barium borate glass for broadband laser amplification

NASA Astrophysics Data System (ADS)

Vázquez, G. V.; Muñoz H., G.; Camarillo, I.; Falcony, C.; Caldiño, U.; Lira, A.

2015-08-01

Spectroscopic parameters of a novel Nd3+-activated barium borate (BBONd) glass have been analyzed for broadband laser amplification. The Judd-Ofelt (JO) intensity parameters were determined through a systematic analysis of the absorption spectrum of Nd3+ ions in the BBONd glass. High values of the JO intensity parameters reveal a great centro-symmetrical loss of the Nd3+ sites and high covalency degree of the ligand field. The very high Ω6 intensity parameter value makes evident both a great structural distortion of the Nd3+ sites and a strong electron-phonon coupling between Nd3+ and free OH- ions, which is consistent with the phonon energy maximum (3442.1 cm-1) recorded by Raman spectroscopy. This strong electron-phonon coupling favors high effective bandwidth and gain bandwidth values of the laser emission (4F3/2 → 4I11/2) of Nd3+ ions. The electric-dipole oscillator strengths of all the Nd3+ absorption transitions, and in particular that of the hypersensitive transition (4I9/2 → 4G5/2), are enhanced by this great structural distortion of the host. Broadband laser amplification of the 4F3/2 → 4I11/2 emission (1062 nm) of Nd3+ ions in the BBONd glass pumped at 805 nm (4I9/2 → 4F5/2 + 2H9/2) is evaluated through the main fluorescent parameters in competition with non-radiative processes. In general, the BBONd glass exhibits spectroscopic parameters comparable with those reported in the literature for broadband laser amplification into the IR region.

Judd-Ofelt Parameters via Bayesian Inference

NASA Astrophysics Data System (ADS)

Silva, Valdeir A.; Silva, José W.; de Morais, Paulo C.; Dantas, Noelio O.

2018-04-01

Bayesian inference was used as a new approach to calculate of rare earth (RE) ion spectroscopic parameters within the Judd-Ofelt theory using the Li2O-B2O3-Al2O3 glass system doped with Nd2O3 and TiO2. This system was synthesized by the fusion method, and the physical properties of the as-synthesized material were investigated. Optical absorption, photoluminescence, micro-Raman, mass density, refractive index, and radiative lifetime calcuations were performed. We investigated the effects of crystal field changes on Nd3+-ions caused due to co-doping with increasing TiO2 content. We observed that co-doping with TiO2 altered the radiative transition rates A( J, J '), favored symmetry enhancement around the Nd3+-ions, and promoted the onset of vibrational modes, contributed to the attenuation of O-H bonds, and substantially increased the spectroscopic quality, χ.

Variation of photoluminescence features in Pr{sup 3+} doped lithium-fluoro-borate glass by changing different modifier oxides (MgO, CaO, CdO and PbO)-Judd-Ofelt theory application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balakrishna, A.; Rajesh, D.; Babu, S.

2015-06-24

Pr{sup 3+} (1.0 mol%) doped different modifier oxide based six lithium-fluoro-borate glasses with chemical composition of 49Li{sub 2}B{sub 4}O{sub 7}-20BaF{sub 2}-10NaF-20MO (where M= Mg, Ca, Cd and Pb), 49Li{sub 2}B{sub 4}O{sub 7}-20BaF{sub 2}-10NaF-10MgO-10CaO and 49Li{sub 2}B{sub 4}O{sub 7}-20BaF{sub 2}-10NaF-10CdO-10PbO were prepared by conventional melt quenching technique. Judd-Ofelt theory has been applied for evaluating the Judd-Ofelt intensity parameters for Pr{sup 3+} ion in these glass compositions and are in turn to used to predict radiative properties such as radiative transition probabilities (A{sub T}), branching ratios (β) and stimulated emission cross-section (σ{sub P}). Stimulated emission cross-section (σ{sub p}) of prominent emission transitions,more » {sup 3}P{sub 0}→{sup 3}H{sub 4} and {sup 1}D{sub 2}→{sup 3}H{sub 4} of Pr{sup 3+} ion in all lithium-fluoro-borate glasses were calculated. Among all the emission transitions, {sup 3}P{sub 0}→{sup 3}H{sub 4} posseses higher branching ratio and stimulated emission cross-section in Mg-Ca glass, which leads to the best laser excitation at 487 nm wavelength.« less

High output power of differently cut Nd:MgO:LiTaO3 CW lasers

NASA Astrophysics Data System (ADS)

Sun, D. H.; Liu, S. D.; Wang, D. Z.; Sang, Y. H.; Kang, X. L.; Liu, H.; Bi, Y.; Yan, B. X.; He, J. L.; Wang, J. Y.

2013-04-01

A high-quality Nd3+ and Mg2+ co-doped LiTaO3 (Nd:MgO:LT) crystal was grown by the Czochralski method. The polarized absorption spectra and fluorescence spectra were studied, and the absorption cross section was calculated by Judd-Ofelt (J-O) theory. The laser performance with different sample cuts of the crystal was investigated for the first time, and it was found that Nd:MgO:LT crystal with different cutting directions (a and c) exhibits different laser properties. By optimizing a partial reflectivity mirror in the laser experimental setting, a high continuous wave output power of 3.58 W was obtained at 1092 and 1076 nm with an optical-to-optical conversion efficiency of 22.78% and slope efficiency of 26.06%. The results indicate that Nd:MgO:LT crystal is a promising candidate for the manufacture of Nd3+ doped periodically poled MgO:LiTaO3 crystal (Nd:PPMgOLT), which should have considerable applications in self-frequency doubling and optical parametric oscillation laser devices.

Spectroscopic studies of Dy3 + ion doped tellurite glasses for solid state lasers and white LEDs

NASA Astrophysics Data System (ADS)

Himamaheswara Rao, V.; Syam Prasad, P.; Mohan Babu, M.; Venkateswara Rao, P.; Satyanarayana, T.; Luís F., Santos; Veeraiah, N.

2018-01-01

Rare earth ion Dy3 +-doped tellurite glasses were synthesised in the system of (75-x)TeO2-15Sb2O3-10WO3-xDy2O3 (TSWD glasses). XRD and FTIR characterizations were used to find the crystalline and structural properties. The intensities of the electronic transitions and the ligand environment around the Dy3 + ion were determined using the Judd-Ofelt (J-O) theory on the absorption spectra of the glasses. The measured luminescence spectra exhibit intense emissions at 574 and 484 nm along with less intense emissions around 662 and 751 nm. Various radiative properties of the 4F9/2 excited level of Dy3 + ion were calculated for the glasses. Decay profiles were measured to find the life times and quantum efficiencies. Yellow to blue intensity ratio (Y/B), CIE chromaticity coordinates and correlated color temperature (CCT) values are calculated using the emission spectra to evaluate the emitted light. The obtained results suggest the utility of the glasses for potential yellow laser and white LED's applications.

Driving the photoluminescent and structural properties of X2-Y2SiO5 by varying the dopant Dy3+ concentration towards cool WLED applications

NASA Astrophysics Data System (ADS)

Ramakrishna, G.; Nagabhushana, H.; Hareesh, K.; Sunitha, D. V.

2017-07-01

Dy3+ doped Y2SiO5 nanophosphors were synthesized by solution combustion technique using Calotropis gigantean milk latex and NaCl as fuel and flux respectively. Powder X-ray diffraction (PXRD) confirmed the formation of monoclinic X2-phase Y2SiO5 belonging to the phase group C2/c. Fourier transform infrared spectroscopy (FTIR) shows characteristic metal-oxygen (Y-O) vibration band at 721 cm-1. Transmission electron microscopic (TEM) and Scanning electron microscopic (SEM) morphological feature exhibits non-uniform almost spherical shaped nanosized particles. The photoluminescence (PL) emission peaks, recorded at 388 nm, showed radiative emissions at 483, 575 and 636 nm respectively. Judd-Ofelt (JO) analysis was carried out to estimate the radiative (AR) properties, radiative life time (τR), branching ratio (βR) and stimulated emission crossection (σλp). The CIE and CCT was estimated using McCamy empirical formula. In the beginning, the CIE co-ordinate values were lying in the light blue region. However, with increase in Dy3+ concentration the values shifted towards white region. CCT value was found to be ∼6984 K. Therefore, Y2SiO5:Dy3+ (9 mol%) can be used for cool day light and WLED applications.

Optical studies of Sm³⁺ ions doped zinc alumino bismuth borate glasses.

PubMed

Swapna, K; Mahamuda, Sk; Srinivasa Rao, A; Shakya, S; Sasikala, T; Haranath, D; Vijaya Prakash, G

2014-05-05

Zinc Alumino Bismuth Borate (ZnAlBiB) glasses doped with different concentrations of samarium (Sm(3+)) ions were prepared by using melt quenching technique and characterized for their lasing potentialities in visible region by using the techniques such as optical absorption, emission and emission decay measurements. Radiative properties for various fluorescent levels of Sm(3+) ions were estimated from absorption spectral information using Judd-Ofelt (JO) analysis. The emission spectra and con-focal photoluminescence images obtained by 410 nm laser excitation demonstrates very distinct and intense orange-red emission for all the doped glasses. The suitable concentration of Sm(3+) ions in these glasses to act as an efficient lasing material has been discussed by measuring the emission cross-section and branching ratios for the emission transitions. The quantum efficiencies were also been estimated from emission decay measurements recorded for the (4)G5/2 level of Sm(3+) ions. From the measured emission cross-sections, branching ratios, strong photoluminescence features and CIE chromaticity coordinates, it was found that 1 mol% of Sm(3+) ions doped ZnAlBiB glasses are most suitable for the development of visible orange-red lasers. Copyright © 2014 Elsevier B.V. All rights reserved.

Structural and luminescence behavior of Er(3+) ions doped Barium tellurofluoroborate glasses.

PubMed

Annapoorani, K; Maheshvaran, K; Arunkumar, S; Suriya Murthy, N; Marimuthu, K

2015-01-25

Er(3+) doped Barium tellurofluoroborate glasses (BTFBxE) with the chemical composition (30-x)TeO2+30B2O3+20BaO+20BaF+xEr2O3 (where x=0.01, 0.05, 0.1, 0.5, 1.0 and 2.0 in wt%) were prepared following the melt quenching technique. The different vibrational modes of borates and tellurites in the prepared glasses were explored through FTIR and Raman spectra. The optical absorption spectra have been used to determine the ionic/covalent nature of the metal-ligand bond in the prepared glasses with the help of Nephelauxetic ratio (β) and bonding parameter (δ) studies. The optical band gap of direct and indirect allowed transitions were determined from Tauc's plot and the variations of band gap energy with structural arrangements were discussed. The Urbach energy values were determined and the relatively lower values of the Urbach's energy reveal the minimal degree of disorderness in the prepared glasses. The oscillator strengths (fexp and fcal) and Judd-Ofelt (JO) intensity parameters (Ω2, Ω4 and Ω6) were calculated with the application of JO theory and the trends of the JO intensity parameters are found to be Ω2>Ω6>Ω4 for all the prepared glasses with a minimum variation in Ω2 intensity parameter values. A bright green emission was observed from the (2)H11/2+(4)S3/2→ (4)I15/2 transition and the radiative properties such as transition probability (A), stimulated emission cross-section (σP(E)), branching ratio (βr) and radiative lifetime (τ) were calculated using the JO parameters. The suitability of the prepared glasses for the fabrication of photonic devices were also discussed and reported in the present work. Copyright © 2014 Elsevier B.V. All rights reserved.

Fluorescence properties and energy transfer study of Er3+/Nd3+ doped fluorophosphate glass pumped at 800 and 980 nm for mid-infrared laser applications

NASA Astrophysics Data System (ADS)

Tian, Ying; Xu, Rongrong; Hu, Lili; Zhang, Junjie

2012-04-01

The fluorescence properties of 2.7 μm emission as well as near infrared emissions in Er3+/Nd3+ doped fluorophosphate glasses are investigated under 800 and 980 nm excitation. The fluorescence dynamics and energy transfer processes between Er and Nd ions in different pumping schemes are reported. Three Judd-Ofelt intensity parameters, energy transfer microparameters, and efficiency have been determined using the Judd-Ofelt and Förster-Dexter theories. The calculated energy transfer efficiency of the Er3+:4I13/2 level to the Nd3+:4I15/2 level is as high as 83.91%. The results indicate that Nd3+ may be an efficient sensitizer for Er3+ to obtain mid-infrared emission and the more suitable pumping scheme of 2.7 μm laser applications for Er3+/Nd3+ doped fluorophosphate glass is 980 nm excitation.

Spectroscopic properties of heavily Ho3+-doped barium yttrium fluoride crystals

NASA Astrophysics Data System (ADS)

Ji, En-Cai; Liu, Qiang; Nie, Ming-Ming; Luo, Hui; Hu, Yu-Xi; Guan, Zhou-Guo; Gong, Ma-Li

2015-09-01

The 30 at.% Ho: BaY2F8 crystals were grown by the Czochralski method, and their spectroscopic properties are analyzed systematically by standard Judd-Ofelt theory. The Judd-Ofelt intensity parameters are estimated to be Ω2 = 6.74 × 10-20 cm2, Ω4 = 1.20 × 10-20 cm2, and Ω6 = 0.66 × 10-20 cm2, and the fluorescence branching ratios and radiative lifetimes for a series of excited state manifolds are also determined. The emission cross sections with our measured infrared luminescence spectra, especially important for 4.1 μm, are calculated to be about 4.37 × 10-21 cm2. The crystal quality is preliminarily tested through a mid-infrared laser emission experiment. Project supported by the National Natural Science Foundation of China (Grant No. 61275146), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20120002110066), and the Special Program of the Co-construction with Beijing Municipal Government of China (Grant No. 20121000302).

Comparative Photoluminescence Properties and Judd-Ofelt Analysis of Eu3+ Ion-Activated Metal Molybdate Phosphors A2MoO6:Eu3+ (A = La, Y, Gd and Bi)

NASA Astrophysics Data System (ADS)

Han, Bing; Liu, Bingkun; Zhang, Jie; Li, Pengju; Shi, Hengzhen

2017-07-01

A class of red-emitting Eu3+ ion-activated metal molybdate A2MoO6:Eu3+ (A = La, Y, Gd and Bi) phosphors were synthesized by a conventional high-temperature solid-state reaction method. The x-ray diffraction patterns, scanning electron microscope images, Fourier transform infrared spectra, ultraviolet-visible diffuse reflection spectra as well as photoluminescence properties were measured to characterize the as-prepared samples. The photoluminescence properties including excitation/emission spectra, decay curves, Commission Internationale de L'Eclairage chromaticity coordinates and quantum efficiency were comparatively investigated in detail. The Judd-Ofelt theory was also applied to understand the radiative properties of f-f transitions of Eu3+ ions in this system for the first time. The as-prepared phosphors can be effectively excited with near-ultraviolet and/or blue light, and exhibit red emission belonging to the prevailing 5D0 → 7F2 transitions of Eu3+ with short decay time (millisecond level). The results demonstrated that A2MoO6:Eu3+ (A = La, Y, Gd and Bi) phosphors could have potential application as red-emitting phosphors in white light-emitting diodes based on near-ultraviolet and/or blue light-emitting diode chips.

Spectroscopic studies of Dy3+ ion doped tellurite glasses for solid state lasers and white LEDs.

PubMed

V, Himamaheswara Rao; P, Syam Prasad; M, Mohan Babu; P, Venkateswara Rao; T, Satyanarayana; Luís F, Santos; N, Veeraiah

2018-01-05

Rare earth ion Dy 3+ -doped tellurite glasses were synthesised in the system of (75-x)TeO 2 -15Sb 2 O 3 -10WO 3 -xDy 2 O 3 (TSWD glasses). XRD and FTIR characterizations were used to find the crystalline and structural properties. The intensities of the electronic transitions and the ligand environment around the Dy 3+ ion were determined using the Judd-Ofelt (J-O) theory on the absorption spectra of the glasses. The measured luminescence spectra exhibit intense emissions at 574 and 484nm along with less intense emissions around 662 and 751nm. Various radiative properties of the 4 F 9/2 excited level of Dy 3+ ion were calculated for the glasses. Decay profiles were measured to find the life times and quantum efficiencies. Yellow to blue intensity ratio (Y/B), CIE chromaticity coordinates and correlated color temperature (CCT) values are calculated using the emission spectra to evaluate the emitted light. The obtained results suggest the utility of the glasses for potential yellow laser and white LED's applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Luminescence performance of Eu{sup 3+} doped lead free zinc phosphate glasses for red emission

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prasad, V. Reddy; Babu, S.; Ratnakaram, Y. C., E-mail: ratnakaramsvu@gmail.com

2016-05-06

Luminescence performance of zinc phosphate glasses containing Eu{sup 3+} ion with the chemical compositions (60-x)NH{sub 4}H{sub 2}PO{sub 4}-20ZnO-10BaF{sub 2}-10NaF-x Eu{sub 2}O{sub 3} (where x = 0.2, 0.5, 1.0 and 1.5 mol%) has been studied. The Fourier Transform Infrared Spectroscopy (FT-IR) shows several vibrations bands. Luminescence spectra of these glasses exhibit characteristic emission of Eu{sup 3+} ion with an intense and most prominent red emission (614 nm) which is attributed to {sup 5}D{sub 0}→{sup 7}F{sub 2} transition. Judd-Ofelt (Ω{sub 2}, Ω{sub 4}) parameters have been evaluated from the luminescence intensity ratios of {sup 5}D{sub 0}→{sup 7}F{sub J} (where J = 2 and 4)more » to {sup 5}D{sub 0}→{sup 7}F{sub 1} transition as well as absorption spectra under different constraints. Using J-O parameters and excitation spectra, the radiative parameters are calculated for different Eu{sup 3+} doped glasses.« less

Broadband ∼3 μm mid-infrared emission in Dy3+/Yb3+ co-doped germanate glasses

NASA Astrophysics Data System (ADS)

Shen, Lingling; Wang, Ning; Dou, Aoju; Cai, Yangjian; Tian, Ying; Huang, Feifei; Xu, Shiqing; Zhang, Junjie

2018-01-01

The Dy3+/Yb3+ co-doped germanate glasses with good thermal stability have been prepared by the conventional melt quenching method. The J-O intensity parameters and radiative properties such as spontaneous transition probilities (Arad), fluorescence branching ratios (β) and radiative lifetimes (τrad) were investigated according to the absorption spectrum based on Judd-Ofelt theory. An intense emission around ∼3 μm with the FWHM reaching to 322 nm was obtained in present glasses excited by 980 nm LD. The high spontaneous transition probability (63.94 s-1), large emission cross section (6.0 × 10-21 cm2) and superior gain performance corresponding to the Dy3+: 6H13/2 → 6H15/2 transition were obtained. Moreover, the energy transfer mechanism was analyzed qualitatively, and it was found that the energy transfer from Yb3+: 2F5/2 to Dy3+: 6H5/2 level could be quite efficient. Hence, the results indicated that the prepared Dy3+/Yb3+ co-doped germanate glass could be a potential candidate for ∼3 μm mid-infrared solid state lasers.

Nd3+-doped lanthanum lead boro-tellurite glass for lasing and amplification applications

NASA Astrophysics Data System (ADS)

Madhu, A.; Eraiah, B.; Manasa, P.; Srinatha, N.

2018-01-01

Nd3+-doped lanthanum lead boro-tellurite glass samples were prepared by conventional melt quenching method and their structural, thermal, fluorescence, and decay times of the glasses were investigated. Prepared glass samples exhibits amorphous nature and shows good thermal stability in the temperature range of 100-800 °C. Judd-Ofelt (JO) analysis was carried out and the intensity parameters (Ωλ = 2, 4, 6) also spontaneous radiative probability and stimulated-.emission cross-sections were estimated. The magnitude of Ωλ confirms the covalency nature. The near infrared emission spectra were measured by 808 nm excitation in which the emission intensity is found to be high at 1060 nm for the 4F3/2 → 4F11/2 transition. The stimulated cross section, effective band width and branching ratios are found to be 8.910 × 10-20 cm2, 21.57 nm and 53.72 % respectively, for 4F3/2 → 4F11/2 transition. The derived gain bandwidth, figure of merit, threshold and saturation intensity found to be comparable to some of the glass systems. Furthermore, the time decay rate found to decrease from 100 μs to 27 μs when the concentration increased from 0.1 to 3.0 mol% of Nd3+ ions and also all follow the single exponential behaviour which is attributed to the self quenching effect due to the cross-relaxation channels.

Concentration-dependent studies of Nd3+ -doped zinc phosphate glasses for NIR photoluminescence at 1.05 μm.

PubMed

Reddy Prasad, V; Seshadri, M; Babu, S; Ratnakaram, Y C

2017-05-01

Nd 3 + -doped lead-free zinc phosphate glasses with the chemical compositions (60-x) NH 4 H 2 PO 4  + 20ZnO + 10BaF 2  + 10NaF + xNd 2 O 3 (where x = 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) were prepared using a melt quenching technique. Vibrational bands were assigned and clearly elucidated by Raman spectral profiles for all the glass samples. Judd-Ofelt (J-O) intensity parameters (Ω λ : λ = 2, 4, 6) were obtained from the spectral intensities of different absorption bands of Nd 3 + ions. Radiative properties such as radiative transition probabilities (A R ), radiative lifetimes (τ R ) and branching ratios (β R ) for different excited states were calculated using J-O parameters. The near infrared (NIR) photoluminescence spectra exhibited three emission bands ( 4 F 3 /2 level to 4 I 13 /2 , 4 I 11 /2 and 4 I 9 /2 states) for all the concentrations of Nd 3 + ions. Various luminescence properties were studied by varying the Nd 3 + concentration for the three spectral profiles. Fluorescence decay curves of the 4 F 3 /2 level were recorded. The energy transfer mechanism that leads to quenching of the 4 F 3 /2 state lifetimes was discussed at higher concentration of Nd 3 + ions. These glasses are suggested as suitable hosts to produce efficient lasing action in NIR region at 1.05 μm. Copyright © 2016 John Wiley & Sons, Ltd.

Improvement of Er 3+ emissions in oxyfluoride glass ceramic nano-composite by thermal treatment

NASA Astrophysics Data System (ADS)

Chen, Daqin; Wang, Yuansheng; Yu, Yunlong; Ma, En

2006-05-01

In order to improve the 1.53 μm emission of Er 3+-doped oxyfluoride glass ceramic containing CaF 2 nano-crystals, series of samples with same Er 3+ doping lever thermal treated under different conditions were prepared. The UV-VIR-NIR absorption spectra, near-infrared and up-conversion emission spectra, and 4I13/2 decay curves were measured. Based on Judd-Ofelt theory, the radiative transition probability, fluorescence branching ratio and radiative decay time of various metastable transitions of precursor glass and glass ceramics were evaluated. With the increasing of heating temperature, the Judd-Ofelt intensity parameter Ω2 monotonously decreased from 4.39×10 -20 to 2.72×10 -20 cm 2; the emission lifetime and quantum efficiency significantly increased from 5.9 to 8.0 ms and 70% to 98%, respectively. The wavelength dependence of gain cross-sections of oxyfluoride glass and glass ceramics were computed to be relatively flat in the range of 1530-1565 nm for population inversion from 0.7 to 1.0.

Kinetics and its accompanying thermodynamics studies on simultaneous complexation of heterobimetallic neodymium (III) with zinc (II) and L-tryptophan in aquated DMF using 4f-4f absorption spectra.

PubMed

Huidrom, Bimola; Singh, N Rajmuhon

2014-01-24

The 4f-4f absorption spectra of the simultaneous heterobimetallic complexation of trivalent neodymium ion with l-tryptophan and divalent zinc ion in aquated DMF (50%, v/v) at pH 6.0 was recorded at the time interval of 1h. From the observed absorption spectra, the values of intensity parameters such as oscillator strength (P) and Judd-Ofelt intensity (Tλ) parameters, kinetics and thermodynamics parameters were evaluated. The rate constant increases with an increase in the temperature along with the oscillator strengths and Judd-Ofelt intensity parameters. The positive values of the change in the standard enthalpy (ΔH°) and entropy (ΔS°) indicate that the complexation is endothermic. The negative values of the change in the standard free energy (ΔG°) in the range from 293.15 K to 308.15 K, indicate that the reaction occurs spontaneously and hence the formation of heterobimetallic complex in the solution is favored kinetically and thermodynamically. Copyright © 2013 Elsevier B.V. All rights reserved.

Kinetics and its accompanying thermodynamics studies on simultaneous complexation of heterobimetallic neodymium (III) with zinc (II) and L-tryptophan in aquated DMF using 4f-4f absorption spectra

NASA Astrophysics Data System (ADS)

Huidrom, Bimola; Rajmuhon Singh, N.

2014-01-01

The 4f-4f absorption spectra of the simultaneous heterobimetallic complexation of trivalent neodymium ion with L-tryptophan and divalent zinc ion in aquated DMF (50%, v/v) at pH 6.0 was recorded at the time interval of 1 h. From the observed absorption spectra, the values of intensity parameters such as oscillator strength (P) and Judd-Ofelt intensity (Tλ) parameters, kinetics and thermodynamics parameters were evaluated. The rate constant increases with an increase in the temperature along with the oscillator strengths and Judd-Ofelt intensity parameters. The positive values of the change in the standard enthalpy (ΔH°) and entropy (ΔS°) indicate that the complexation is endothermic. The negative values of the change in the standard free energy (ΔG°) in the range from 293.15 K to 308.15 K, indicate that the reaction occurs spontaneously and hence the formation of heterobimetallic complex in the solution is favored kinetically and thermodynamically.

Lanthanide-Doped KLu2F7 Nanoparticles with High Upconversion Luminescence Performance: A Comparative Study by Judd-Ofelt Analysis and Energy Transfer Mechanistic Investigation

NASA Astrophysics Data System (ADS)

Xu, Dekang; Li, Anming; Yao, Lu; Lin, Hao; Yang, Shenghong; Zhang, Yueli

2017-02-01

The development, design and the performance evaluation of rare-earth doped host materials is important for further optical investigation and industrial applications. Herein, we successfully fabricate KLu2F7 upconversion nanoparticles (UCNPs) through hydrothermal synthesis by controlling the fluorine-to-lanthanide-ion molar ratio. The structural and morphological results show that the samples are orthorhombic-phase hexagonal-prisms UCNPs, with average side length of 80 nm and average thickness of 110 nm. The reaction time dependent crystal growth experiment suggests that the phase transformation is a thermo-dynamical process and the increasing F-/Ln3+ ratio favors the formation of the thermo-dynamical stable phase - orthorhombic KLu2F7 structure. The upconversion luminescence (UCL) spectra display that the orthorhombic KLu2F7:Yb/Er UCNPs present stronger UCL as much as 280-fold than their cubic counterparts. The UCNPS also display better UCL performance compared with the popular hexagonal-phase NaREF4 (RE = Y, Gd). Our mechanistic investigation, including Judd-Ofelt analysis and time decay behaviors, suggests that the lanthanide tetrad clusters structure at sublattice level accounts for the saturated luminescence and highly efficient UCL in KLu2F7:Yb/Er UCNPs. Our research demonstrates that the orthorhombic KLu2F7 is a promising host material for UCL and can find potential applications in lasing, photovoltaics and biolabeling techniques.

Effect of alkaline earth oxides on the physical and spectroscopic properties of Dy3+- doped Li2O-B2O3 glasses for white emitting material application

NASA Astrophysics Data System (ADS)

Shamshad, L.; Rooh, G.; Kirdsiri, K.; Srisittipokakun, N.; Damdee, B.; Kim, H. J.; Kaewkhao, J.

2017-02-01

Li2O-MO-B2O3:0.5Dy2O3 glasses mixed with four different alkaline earth modifier oxides MgO, CaO, SrO and BaO were synthesized by melt quench technique. Their physical properties like density, molar volume and refractive index were measured at room temperature and the effect of alkaline earth modifier oxides were studied. Also, optical absorption and photoluminescence spectra of these glasses have been acquired at room temperature. The Judd-Ofelt theory was effectively used to characterize these spectra and spectral intensities (ƒcal), Judd-Ofelt intensity parameters (Ω2, Ω4 and Ω6) and certain radiative properties have been determined. Radiative life-times (τR), branching ratios (βcal), and emission cross-sections (σp) and optical gain parameters (σp × τR) were calculated from the Judd-Ofelt intensity parameters and the variation in these parameters with the variation of glass matrix are discussed. Yellow/Blue (Y/B) ratio and chromacity color coordinates (x,y) are calculated from the emission spectra which indicates the white light generation from all the investigated samples. The correlated color temperature (CCT) for the studied glasses is found to be 4418 K. The fluorescence decay time (τexp) of the 4F9/2 level of Dy3+ has been measured from the decay profiles and compared with calculated lifetimes (τcal). Among all the studied glass matrices, the glass containing BaO exhibits high value of branching ratio, large emission cross-section and high optical gain parameter for 6F9/2 → 6H13 at 575 nm. The results indicates the suitability of all the studied glasses for laser action and white light generation.

Optical characterization of Nd (3+):AgBr.

PubMed

Bunimovich, D; Nagli, L; Katzir, A

1997-10-20

The luminescence of silver bromide crystals, doped with neodymium, was investigated over the visible and near-infrared spectral ranges. The emission, excitation, and absorption spectra were measured over a broad temperature range. The absolute luminescence quantum yield was estimated by comparing the luminescence with that of a neodymium-doped phosphate glass, for which the manufacturer gives a value of 0.4. The Judd-Ofelt analysis was applied to both materials, and transition rates, branching ratios, and quantum efficiencies were calculated for all the observed bands. Good agreement was obtained between theory and experiment.

Rare-Earth Ion-Host Lattice Interactions: 15. Analysis of the Spectra of Nd3+ in Gd3Sc2Ga3O12.

DTIC Science & Technology

1984-05-01

Luminescence of Cr3+ Ions in Gadolinium Gallium and Gadolinium Scandium Gallium Garnet CT’stals, Soy. J. Quant. Electron. 12 (1982), 1124. 6M. Dutoit, J. C...Shcherbakov, Absolute Quantum Efficiency of the Luminescence of Cr3+ Ions in Gadolinium Gallium and Gadolinium Scandium Gallium Garnet Crystals, Soy. J...HDL Project: 324332 19. KEY WORDS (Continue on reverse side it necessary end Identify by block number) Rare earth Mixed garnet Spectra Laser Judd-Ofelt

Spectroscopic properties of Sm3 + ions doped Alkaliborate glasses for photonics applications

NASA Astrophysics Data System (ADS)

Nagaraj, R.; Suthanthirakumar, P.; Vijayakumar, R.; Marimuthu, K.

2017-10-01

A new series of Sm3 + doped alkaliborate glasses have been prepared by melt quenching technique and their structural and spectroscopic properties were analysed employing XRD, FTIR, optical absorption, photoluminescence and decay spectral measurements in order to explore their suitability for photonic applications. The amorphous nature have been confirmed through XRD analysis and the FTIR spectra reveal the presence of fundamental stretching and bending vibrations of the borate networks in the prepared glasses. From the absorption peak positions, bonding parameter (δ) values were calculated to examine the nature of the metal-ligand bond. The optical band gap (Eopt) corresponds to the direct and indirect allowed transitions and the Urbach energies (ΔE) were calculated from the absorption spectra to understand the electronic band structure of the studied glasses. The Judd-Ofelt (JO) intensity parameters Ωλ (λ = 2, 4 and 6) were determined to explore the symmetry of the ligand environment around the Sm3 + ions in the studied glasses. The luminescence spectra exhibit four emission bands in the visible region due to the 4G5/2 → 6H5/2, 6H7/2, 6H9/2 and 6H11/2 transitions. The radiative parameters such as transition probability (A), stimulated emission cross-section (σPE), branching ratios (βR) and radiative lifetime (τR) have been determined from the luminescence spectra using JO theory to ensure the suitability of the studied glasses for optoelectronic applications. The luminescence spectra were characterized through CIE 1931 chromaticity diagram to examine the dominant emission color of the studied glasses. The lifetime values of the Sm3 + doped studied glasses pertaining to the 4G5/2 excited level have been determined through decay curve measurements and the non-exponential decay curves were fitted to the Inokuti-Hirayama model to analyze the energy transfer mechanism between the nearby Sm3 + ions. The obtained results were discussed and compared with the similar reported glasses.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fares, Hssen; Férid, Mokhtar; Elhouichet, Habib, E-mail: habib.elhouichet@fst.rnu.tn

Tellurite glasses doped Er³⁺ ions and containing Silver nanoparticles (Ag NPs) are prepared using melt quenching technique. The nucleation and growth of Ag NPs were controlled by a thermal annealing process. The X-ray diffraction pattern shows no sharp peak indicating an amorphous nature of the glasses. The presence of Ag NPs is confirmed from transmission electron microscopy micrograph. Absorption spectra show typical surface plasmon resonance (SPR) band of Ag NPs within the 510–550 nm range in addition to the distinctive absorption peaks of Er³⁺ ions. The Judd-Ofelt (J-O) intensity parameters, oscillator strengths, spontaneous transition probabilities, branching ratios, and radiative lifetimesmore » were successfully calculated based on the experimental absorption spectrum and the J-O theory. It was found that the presence of silver NPs nucleated and grown during the heat annealing process improves both of the photoluminescence (PL) intensity and the PL lifetime relative to the ⁴I 13/2 → ⁴I 15/2 transition. Optimum PL enhancement was obtained after 10 h of heat-treatment. Such enhancements are mainly attributed to the strong local electric field induced by SPR of silver NPs and also to energy transfer from the surface of silver NPs to Er³⁺ ions, whereas the quenching is ascribed to the energy transfer from Er³⁺ ions to silver NPs. Using the Mc Cumber method, absorption cross-section, calculated emission cross-section, and gain cross-section for the ⁴I 13/2 → ⁴I 15/2 transition were determined and compared for the doped and co-doped glasses. The present results indicate that the glass heat-treated for 10 h has good prospect as a gain medium applied for 1.53 μm band broad and high-gain erbium-doped fiber amplifiers.« less

Optical and spectroscopic study of erbium doped calcium borotellurite glasses

NASA Astrophysics Data System (ADS)

Gomes, J. F.; Lima, A. M. O.; Sandrini, M.; Medina, A. N.; Steimacher, A.; Pedrochi, F.; Barboza, M. J.

2017-04-01

In this study, 10CaF2 - (29.9-0.4x)CaO - (60-0.6x)B2O3 - xTeO2 - 0,1Er2O3 (x = 10, 16, 22, 30 and 50 mol %) glasses were synthesized, and their optical and spectroscopic properties were investigated. X-ray diffraction, density, glass transition temperature (Tg), crystallization temperature (Tx), refraction index, luminescence, radiative lifetime and optical absorption measurements were carried out. Molar volume (Vm), thermal stability (Tx-Tg), electronic polarizability (αm), optical bang gap energy (Eg) and Judd-Ofelt (JO) parameters Ωt (2,4,6) were also calculated. The results are discussed in terms of tellurium oxide content. The increase of TeO2 in the glasses composition increases density, refractive index and electronic polarizability. The optical band gap energy decreases varying from 3.37 to 2.71 eV for the glasses with 10 and 50 mol% of TeO2, respectively. The optical absorption coefficient spectra show characteristic bands of Er3+ ions. Furthermore, these spectra in NIR region show a decrease of hydroxyl groups as a function of TeO2 addition. Luminescence intensity and radiative lifetimes at 1530 nm show an increasing with the TeO2 content. The JO parameters of Er:CaBTeX glasses follow the trend Ω2 > Ω4 > Ω6 and the quality factor values (Ω4/Ω6) were between 1.37 and 3.07. By comparing the measured lifetime with the calculated radiative decay time, quantum efficiency was calculated. The luminescence emission intensity at 1530 nm decreases with the increase of temperature. The lifetime values show a slight trend to decrease with the temperature increase, from 300 to 420 K, for all the samples.

Investigation of luminescence and laser transition of Dy3+ ion in P2O5sbnd PbOsbnd Bi2O3sbnd R2O3 (R = Al, Ga, In) glasses

NASA Astrophysics Data System (ADS)

Ram, G. Chinna; Narendrudu, T.; Suresh, S.; Kumar, A. Suneel; Rao, M. V. Sambasiva; Kumar, V. Ravi; Rao, D. Krishna

2017-04-01

P2O5sbnd PbOsbnd Bi2O3sbnd R2O3 (R = Al, Ga, In) glasses doped with Dy2O3 were prepared by melt quenching technique. The prepared glasses were characterized by XRD, optical absorption, FTIR, luminescence studies. Judd-Ofelt parameters have been evaluated for three glass systems from optical absorption spectra and in turn radiative parameters for excited luminescent levels of Dy3+ ion are also calculated. Emission cross section and branching ratio values are observed to high for 6H13/2 level for Dy3+ ion. The yellow to blue intensity ratios and CIE chromaticity coordinates were calculated. Decay curves exhibit non exponential behavior. Quantum efficiency of prepared glasses was measured by using radiative and calculated life times. IR studies, J-O parameters and Y/B ratio values indicate that more asymmetry around Dy3+ ions in Ga2O3 mixed glass was observed. Chromaticity coordinates lie near ideal white light region. These coordinates and CCT values have revealed that all the prepared glasses emit quality white light especially the glasses mixed with Ga2O3 are suitable for development of white LEDs.

Thermal, spectroscopic and laser properties of Nd3+ in gadolinium scandium gallium garnet crystal produced by optical floating zone method

NASA Astrophysics Data System (ADS)

Tian, Li; Wang, Shuxian; Wu, Kui; Wang, Baolin; Yu, Haohai; Zhang, Huaijin; Cai, Huaqiang; Huang, Hui

2013-12-01

A neodymium-doped gadolinium scandium gallium garnet (Nd:GSGG) single crystal with dimensions of Φ 5 × 20 mm2 has been grown by means of optical floating zone (OFZ). X-ray powder diffraction (XRPD) result shows that the as-grown Nd:GSGG crystal possesses a cubic structure with space group Ia3d and a cell parameter of a = 1.2561 nm. Effective elemental segregation coefficients of the Nd:GSGG as-grown crystal were calculated by using X-ray fluorescence (XRF). The thermal properties of the Nd:GSGG crystal were systematically studied by measuring the specific heat, thermal expansion and thermal diffusion coefficient, and the thermal conductivity of this crystal was calculated. The absorption and luminescence spectra of Nd:GSGG were measured at room temperature (RT). By using the Judd-Ofelt (J-O) theory, the theoretical radiative lifetime was calculated and compared with the experimental result. Continuous wave (CW) laser performance was achieved with the Nd:GSGG at the wavelength of 1062 nm when it was pumped by a laser diode (LD). A maximum output power of 0.792 W at 1062 nm was obtained with a slope efficiency of 11.89% under a pump power of 7.36 W, and an optical-optical conversion efficiency of 11.72%.

Optical and luminescence properties of Dy3+ ions in phosphate based glasses

NASA Astrophysics Data System (ADS)

Rasool, Sk. Nayab; Rama Moorthy, L.; Jayasankar, C. K.

2013-08-01

Phosphate glasses with compositions of 44P2O5 + 17K2O + 9Al2O3 + (30 - x)CaF2 + xDy2O3 (x = 0.05, 0.1, 0.5, 1.0, 2.0, 3.0 and 4.0 mol %) were prepared and characterized by X-ray diffraction (XRD), differential thermal analysis (DTA), Fourier transform infrared (FTIR), optical absorption, emission and decay measurements. The observed absorption bands were analyzed by using the free-ion Hamiltonian (HFI) model. The Judd-Ofelt (JO) analysis has been performed and the intensity parameters (Ωλ, λ = 2, 4, 6) were evaluated in order to predict the radiative properties of the excited states. From the emission spectra, the effective band widths (Δλeff), stimulated emission cross-sections (σ(λp)), yellow to blue (Y/B) intensity ratios and chromaticity color coordinates (x, y) have been determined. The fluorescence decays from the 4F9/2 level of Dy3+ ions were measured by monitoring the intense 4F9/2 → 6H15/2 transition (486 nm). The experimental lifetimes (τexp) are found to decrease with the increase of Dy3+ ions concentration due to the quenching process. The decay curves are perfectly single exponential at lower concentrations and gradually changes to non-exponential for higher concentrations. The non-exponential decay curves are well fitted to the Inokuti-Hirayama (IH) model for S = 6, which indicates that the energy transfer between the donor and acceptor is of dipole-dipole type. The systematic analysis of revealed that the energy transfer mechanism strongly depends on Dy3+ ions concentration and the host glass composition.

Luminescent properties of Tb3+- doped TeO2-WO3-GeO2 glasses for green laser applications

NASA Astrophysics Data System (ADS)

Subrahmanyam, T.; Rama Gopal, K.; Padma Suvarna, R.; Jamalaiah, B. C.; Vijaya Kumar, M. V.

2018-06-01

Different concentrations of Tb3+ -doped oxyfluoro tellurite (TWGTb) glasses were prepared by conventional melt quenching technique and characterized for green laser applications. The Judd-Ofelt theory was applied to evaluate various spectroscopic and radiative parameters. The TWGTb glasses exhibit 5D3 → 7F5-3 and 5D4 → 7F6-0 transitions when excited at 316 nm radiation. The variation of intensity of 5D4 → 7F5 (Green) and 5D3 → 7F4 (Blue) transitions and the green to blue (IG/IB) intensity ratios were studied as a function of Tb3+ ions concentration. The laser characteristic parameters such as effective bandwidth (Δλeff), stimulated emission cross-section (σe), gain bandwidth (σe × Δλeff) and optical gain (σe × τR) were determined using the three phenomenological Judd-Ofelt intensity parameters. The fluorescence decay profiles of 5D4 metastable level exhibit single-exponential nature for all the samples. Based on the experimental results we suggest that the 1.0 mol% of Tb3+ -doped TWGTb glass could be a suitable laser host material to emit intense green luminescence at 545 nm.

Lasing transition at 1.06 μm emission in Nd3+ -doped borate-based tellurium calcium zinc niobium oxide glasses for high-power solid-state lasers.

PubMed

Ravi, O; Prasad, K; Jain, Rajiv; Venkataswamy, M; Chaurasia, Shivanand; Deva Prasad Raju, B

2017-08-01

The spectroscopic properties of Tellurium Calcium Zinc Niobium oxide Borate (TCZNB) glasses of composition (in mol%) 10TeO 2  + 15CaO + 5ZnO + 10 Nb 2 O 5  + (60 - x)B 2 O 3  + Nd 2 O 3 (x = 0.1, 0.5, 1.0 or 1.5 mol%) have been investigated experimentally. The three phenomenological intensity parameters Ω 2 , Ω 4, Ω 6 have been calculated using the Judd-Ofelt theory and in turn radiative properties such as radiative transition probabilities, emission cross-sections, branching ratios and radiative lifetimes have been estimated. The trend found in the JO intensity parameter is Ω 2  > Ω 6  > Ω 4 If Ω 6  > Ω 4 , the glass system is favourable for the laser emission 4 F 3 /2  →  4 I 11 /2 in the infrared (IR) wavelength. The experimental values of branching ratio of 4 F 3 /2  →  4 I 11 /2 transition indicate favourable lasing action with low threshold power. The evaluated total radiative transition probabilities (A T ), stimulated emission cross-section (σ e ) and gain bandwidth parameters (σ e  × Δλ p ) were compared with earlier reports. An energy level analysis has been carried out considering the experimental energy positions of the absorption and emission bands. Copyright © 2016 John Wiley & Sons, Ltd.

R2O3 (R = La, Y) modified erbium activated germanate glasses for mid-infrared 2.7 μm laser materials

NASA Astrophysics Data System (ADS)

Cai, Muzhi; Zhou, Beier; Wang, Fengchao; Wei, Tao; Tian, Ying; Zhou, Jiajia; Xu, Shiqing; Zhang, Junjie

2015-08-01

Er3+ activated germanate glasses modified by La2O3 and Y2O3 with good thermal stability were prepared. 2.7 μm fluorescence was observed and corresponding radiative properties were investigated. A detailed discussion of J-O parameters has been carried out based on absorption spectra and Judd-Ofelt theory. The peak emission cross sections of La2O3 and Y2O3 modified germanate glass are (14.3 ± 0.10) × 10-21 cm2 and (15.4 ± 0.10) × 10-21 cm2, respectively. Non-radiative relaxation rate constants and energy transfer coefficients of 4I11/2 and 4I13/2 levels have been obtained and discussed to understand the 2.7 μm fluorescence behavior. Moreover, the energy transfer processes of 4I11/2 and 4I13/2 level were quantitatively analyzed according to Dexter’s theory and Inokuti-Hirayama model. The theoretical calculations are in good agreement with the observed 2.7 μm fluorescence phenomena. Results demonstrate that the Y2O3 modified germanate glass, which possesses more excellent spectroscopic properties than La2O3 modified germanate glass, might be an attractive candidate for mid-infrared laser.

Spectroscopic properties and energy transfer parameters of Er3+-doped fluorozirconate and oxyfluoroaluminate glasses.

PubMed

Huang, Feifei; Liu, Xueqiang; Hu, Lili; Chen, Danping

2014-05-23

Er3+-doped fluorozirconate (ZrF4-BaF2-YF3-AlF3) and oxyfluoroaluminate glasses are successfully prepared here. These glasses exhibit significant superiority compared with traditional fluorozirconate glass (ZrF4-BaF2-LaF3-AlF3-NaF) because of their higher temperature of glass transition and better resistance to water corrosion. Judd-Ofelt (J-O) intensity parameters are evaluated and used to compute the radiative properties based on the VIS-NIR absorption spectra. Broad emission bands located at 1535 and 2708 nm are observed, and large calculated emission sections are obtained. The intensity of 2708 nm emission closely relates to the phonon energy of host glass. A lower phonon energy leads to a more intensive 2708 nm emission. The energy transfer processes of Er3+ ions are discussed and lifetime of Er3+:4I13/2 is measured. It is the first time to observe that a longer lifetime of the 4I13/2 level leads to a less intensive 1535 nm emission, because the lifetime is long enough to generate excited state absorption (ESA) and energy transfer (ET) processes. These results indicate that the novel glasses possess better chemical and thermal properties as well as excellent optical properties compared with ZBLAN glass. These Er3+-doped ZBYA and oxyfluoroaluminate glasses have potential applications as laser materials.

Comparative absorption spectroscopy involving 4f-4f transitions to explore the kinetics of simultaneous coordination of uracil with Nd(III) and Zn(II) and its associated thermodynamics

NASA Astrophysics Data System (ADS)

Victory Devi, Ch.; Rajmuhon Singh, N.

2011-10-01

The interaction of uracil with Nd(III) has been explored in presence and absence of Zn(II) using the comparative absorption spectroscopy involving the 4f-4f transitions in different solvents. The complexation of uracil with Nd(III) is indicated by the change in intensity of 4f-4f bands expressing in terms of significant change in oscillator strength and Judd-Ofelt parameters. Intensification of this bands became more prominent in presence of Zn(II) suggesting the stimulative effect of Zn(II) towards the complexation of Nd(III) with uracil. Other spectral parameters namely Slator-Condon ( Fk's), nephelauxetic effect ( β), bonding ( b1/2) and percent covalency ( δ) parameters are computed to correlate their simultaneous binding of metal ions with uracil. The sensitivities of the observed 4f-4f transitions towards the minor coordination changes around Nd(III) has been used to monitor the simultaneous coordination of uracil with Nd(III) and Zn(II). The variation of intensities (oscillator strengths and Judd-Ofelt parameters) of 4f-4f bands during the complexation has helped in following the heterobimetallic complexation of uracil. Rate of complexation with respect to hypersensitive transition was evaluated. Energy of activation and thermodynamic parameters for the complexation reaction were also determined.

Theoretical and experimental studies of electronic, optical and luminescent properties for Tb-based garnet materials

NASA Astrophysics Data System (ADS)

Ding, Shoujun; Zhang, Haotian; Dou, Renqin; Liu, Wenpeng; Sun, Dunlu; Zhang, Qingli

2018-07-01

Terbium-aluminum (Tb3Al5O12: TAG) as well as Terbium-scandium-aluminum (Tb3Sc2Al3O12: TSAG) garnet materials have attracted tremendous attention around the world owing to their multifunctional applications. However, the electronic structure, optical and luminescent properties for TAG and TSAG are still requiring elucidation. To solve these intriguing problems, firstly, a systematic theoretical calculation based on the density functional theory methods were carried out on them and their electronic structure and optical properties were obtained. The calculated results indicating that both TAG and TSAG belongs to direct band gap materials category with band gap of 4.46 and 4.05 eV, respectively. Secondly, we compared the calculated results with the experimental results (including band gap, refractive index and reflectivity) and found that they were in good coincident. Lastly, we investigated the luminescence properties of TSAG and evaluated its probability for using as visible phosphor and laser matrix. In addition, a Judd-Ofelt theory calculation was performed on TSAG to reveal the radioactive transition of Tb-4f configuration and the three Judd-Ofelt intense parameters were obtained to be 4.47, 1.37 and 4.23 × 10-20 cm2, respectively. All of the obtained results can provide an essential understanding of TAG and TSAG garnet materials and also useful for the further exploration of them.

Spectroscopic properties of Sm3+ doped sodium-tellurite glasses: Judd-Ofelt analysis

NASA Astrophysics Data System (ADS)

Mawlud, Saman Q.; Ameen, Mudhafar M.; Sahar, Md. Rahim; Mahraz, Zahra Ashur Said; Ahmed, Kasim F.

2017-07-01

Modifying the optical response of rare earth doped inorganic glasses for diverse optical applications is the current challenge in materials science and technology. We report the enhancement of the visible emissions of the Sm3+ ions doped sodium-tellurite (TNS) glasses. The impacts of varying Sm3+ ions concentration on the spectroscopic properties of such glass samples are evaluated. Synthesized glass samples are characterized via emission and absorption measurements. The UV-Vis-NIR absorption spectra revealed nine absorption peaks which are assigned to the transitions from the ground level (6H5/2) to 6P3/2, 4I11/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2 and 6F1/2 excited energy levels of Sm3+ ions. Emission spectra of the prepared glass under 404 nm excitation wavelength consisted of four bands centered at 561 nm, 598 nm, 643 nm and 704 nm which are originated from 4G5/2→6HJ (J = 5/2, 7/2, 9/2 and 11/2) transitions. The experimental oscillator strengths, fexp are calculated from the area under absorption bands. Using Judd-Ofelt theory and fit process of least square, the phenomenological intensity parameters Ωλ (λ = 2, 4, 6) are obtained. In order to evaluate potential applications of Sm3+ ions in telluride glasses, the spectroscopic parameters: radiative transition probability AR, branching ratio BR, radiative life time τr and stimulated emission cross section σλ for each band are calculated. These glass compositions could be a potential candidate for lasers.

Optical Studies of Nd-doped benzil, a potential luminescent and laser material

NASA Astrophysics Data System (ADS)

Noginov, M. A.; Curley, M.; Noginova, N.; Wang, W. S.; Aggarwal, M. D.

1998-08-01

Neodymium-doped benzil crystals have been synthesized and characterized for their absorption, emission, and kinetics properties. From Judd Ofelt analysis, the radiative decay time of Nd emission (peaking at 1055 nm) is estimated to be equal to 441 s. The experimental Nd lifetime (under Ar laser excitation) is equal to 19 s. The broad emission band centered at approximately 700 nm ( decay 15 ns) and the Raman scattering with characteristic frequency shift of 1600 cm 1 have been observed at excitation of benzil with 532-nm Q -switched laser pulses. We show that rare-earth-doped benzil can be considered as a potential candidate for luminescent and solid-state laser material.

Optical Studies of Nd-doped benzil, a potential luminescent and laser material.

PubMed

Noginov, M A; Curley, M; Noginova, N; Wang, W S; Aggarwal, M D

1998-08-20

Neodymium-doped benzil crystals have been synthesized and characterized for their absorption, emission, and kinetics properties. From Judd-Ofelt analysis, the radiative decay time of Nd emission (peaking at 1055 nm) is estimated to be equal to 441 mus. The experimental Nd lifetime (under Ar+ laser excitation) is equal to 19 mus. The broad emission band centered at approximately 700 nm (tau(decay) approximately 15 ns) and the Raman scattering with characteristic frequency shift of 1600 cm(-1) have been observed at excitation of benzil with 532-nm Q-switched laser pulses. We show that rare-earth-doped benzil can be considered as a potential candidate for luminescent and solid-state laser material.

Investigations on the spectroscopic properties of Dy3 + ions doped Zinc calcium tellurofluoroborate glasses

NASA Astrophysics Data System (ADS)

Karthikeyan, P.; Arunkumar, S.; Annapoorani, K.; Marimuthu, K.

2018-03-01

A new series of Dy3 + doped (30-x)B2O3 + 30TeO2 + 20CaCO3 + 10ZnO + 10ZnF2 + xDy2O3 (x = 0.01, 0.1, 0.5, 1, 2 and 3 in wt%) Zinc calcium tellurofluoroborate glasses were prepared and their structural, luminescence and excited state dynamics have been studied and reported. The structural properties have been characterized through XRD and FTIR studies to confirm the amorphous nature and to explore the presence of fundamental stretching vibrations. The bonding parameters (δ and β), optical band gap, Urbach's energy, oscillator strengths and Judd-Ofelt (JO) intensity parameters were calculated from the absorption spectra. The JO intensity parameters and the Y/B intensity ratio values have been used to explore the nature of the bonding and asymmetry around the Dy-ligand field environment. The luminescence properties of the present Dy3 + doped glasses have been analyzed through luminescence excited state dynamics and radiative properties such as transition probability (A), stimulated emission cross-section (σPE) branching ratio (β) and radiative lifetime (τR) values. The combination of dominant blue (4F9/2 → 6H15/2) and yellow (4F9/2 → 6H13/2) emissions generates white light emission in the CIE chromaticity diagram thus suggests that the present Dy3 + doped glasses are suitable for white light applications. The lifetime of the 4F9/2 excited state is found to decrease with the increase in Dy3 + ion content and the concentration quenching of the Dy3 + ions emission could be ascribed due to the resonant energy transfer and cross-relaxation processes. The non-exponential behavior of the decay curves has been analyzed with Inokuti-Hirayama model and the interaction between the Dy3 + ions is of electric dipole-dipole in nature.

Photoluminescence characteristics of Eu2O3 doped calcium fluoroborate glasses

NASA Astrophysics Data System (ADS)

Krishnapuram, Pavani; Jakka, Suresh Kumar; Thummala, Chengaiah; Lalapeta, Rama Moorthy

2012-11-01

The present work reports the preparation and characterization of calcium fluoroborate (CFB) glasses doped with different concentrations of Eu2O3. The spectroscopic free-ion parameters are evaluated from the experimentally observed energy levels of Eu3+ ions in CFB glasses by using the free-ion Hamiltonian model (HFI). The phenomenological Judd-Ofelt (J-O) parameters, Ω2, Ω4 and Ω6, are evaluated from the intensities of Eu3+ ion absorption bands by various constraints. From these J-O parameters (Ωλ), the radiative parameters such as transition probabilities (AR), branching ratios (βR), stimulated emission cross sections (σe) and radiative lifetimes (τR) are evaluated for 5D→7(4fASO+αL(L+1)+βG(G2)+γG(R7)+∑j=0,2,4 Mjmj+∑k=2,4,6 PKpK where Eavg includes the kinetic energy of the electrons and their interaction with the nucleus. It shifts only the barycentre of the whole 4fN configuration. Fk (k = 2, 4, 6) are free electron repulsion parameters, ξ4f is the spin-orbit coupling constant, α, β and γ are the three interaction parameters, Mj (j = 0, 2, 4) and Pk (k = 2, 4, 6) are magnetic interaction parameters. Among all the interactions, Fk and ξ4f are the main ones which give rise to the 2LJ levels. The rest only make corrections in the energies of these levels without removing their degeneracy. The parametric fits have been carried out as has been done in our earlier work [16]. The quality of the parametric fit is generally described in terms of the root mean square (rms) deviation, σrms between the experimental and calculated energies by the relation σrms=√{{∑}/{i=1N(Eiexp-Eical)2N}} where Eiexp and Eical are the experimental and calculated energies, respectively, for level 'i' and N denotes the total number of levels included in the energy level fit.

Nd/sup 3 +/ fluorescence quantum-efficiency measurements with photoacoustics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosencwaig, A.; Hildum, E.A.

1981-04-01

We have investigated the use of photoacoustic techniques for obtaining absolute values of fluorescence quantum efficiencies in lightly doped Nd/sup 3 +/ laser materials. We have found that surface absorptions play an important role in gas-microphone measurements, and that thermal profiles are important in piezoelectric measurements. We have obtained fluorescence quantum efficiencies for Nd/sup 3 +/ in yttrium aluminum garnet, and in silicate and borate glasses that are in good agreement with lifetime measurements and Judd-Ofelt calculations.

Preparation and characterization of Tb3+ ions doped zincborophosphate glasses for green emission

NASA Astrophysics Data System (ADS)

Bindu, S. Hima; Raju, D. Siva; Krishna, V. Vinay; Raju, Ch. Linga

2017-06-01

The present study reports the preparation of various concentrations of Tb3+ ions doped zincborophosphate glasses and analysis by XRD, FTIR, optical, emission and decay curve spectras. The effect of borate groups on the phosphate was evidenced by FTIR spectroscopy. The JO intensity parameters was calculated using Judd-Offlet theory. The fluroscence spectra of Tb3+ doped zincborophosphate glasses revealed the efficient blue and green emissions due to 5D3 and 5D4 excited levels to 7Fj ground state respectively. The decay curves exhibits single exponential curves for all the Tb3+ ion concentrations. Various radiative and fluorescence parameters are calculated using JO intensity parameters. Based on the results obtained in the present study, the Tb3+ ions doped zincborophosphate glasses behaves as a efficient laser active materials for highintensity emissions in the green region.

Structural and optical properties of Dy3+ doped Aluminofluoroborophosphate glasses for white light applications

NASA Astrophysics Data System (ADS)

Vijayakumar, M.; Mahesvaran, K.; Patel, Dinesh K.; Arunkumar, S.; Marimuthu, K.

2014-11-01

Dy3+ doped Aluminofluoroborophosphate glasses (BPAxD) have been prepared following conventional melt quenching technique and their structural and optical properties were explored through XRD, FTIR, optical absorption, excitation, emission and decay measurements. The coexistence of BO3 groups in borate rich domain and BO4 groups in phosphate rich domain have been confirmed through vibrational energy analysis. Negative bonding parameter (δ) values indicate that, the metal-ligand environment in the prepared glasses is of ionic in nature. The oscillator strength and the luminescent intensity Ωλ (λ = 2, 4 and 6) parameters are calculated using Judd-Ofelt theory. The radiative properties such as transition probability (A), stimulated emission cross-section (σpE) and branching ratios (β) have been calculated using JO intensity parameters and compared with the reported Dy3+ doped glasses. Concentration effect on Y/B intensity ratios and the CIE chromaticity coordinates were calculated for the generation of white light from the luminescence spectra. The color purity and the correlated color temperature were also calculated and the results are discussed in the present work. The decay of the 4F9/2 excited level is found to be single exponential for lower concentration and become non-exponential for higher concentration. The non-exponential behavior arises due to the efficient energy transfer between the Dy3+ ions through various non-radiative relaxation channels and the decay of the 4F9/2 excited level have been analyzed with IH model. Among the prepared glasses, BPA0.5D glass exhibits higher σpE, βR, σpE×σpE, σpE×Δλeff and η values for the 6H13/2 emission band which in turn specifies its suitability for white LEDs, laser applications and optical amplifiers.

Optical spectroscopy and magnetic behaviour of Sm3+ and Eu3+ cations in Li6Eu1-xSmx(BO3)3 solid solution

NASA Astrophysics Data System (ADS)

Belhoucif, Rekia; Velázquez, Matias; Plantevin, Olivier; Aschehoug, Patrick; Goldner, Philippe; Christian, George

2017-11-01

A new borate solid solution series of powders, Li6Eu1-xSmx(BO3)3 (LSEBx, x = 0.35, 0.5, 0.6, 1), were synthesized by solid-state reaction, characterized and their luminescent properties were investigated. The absorption spectra indicate that absorption takes place mainly from the Sm3+6H5/2 ground state, with a strong band at 405 nm. The photoluminescence spectra reveal that the Eu3+ red emission intensity strongly depends on the Sm3+ content x. Judd-Ofelt theory was applied to experimental data for the quantitative determination of phenomenological parameters Ωi (i = 2, 4, 6) Judd Ofelt parameters, radiative transition rates and emission quantum efficiency. Owing to the energy transfer from Sm3+ to Eu3+ the intense red light detected at 613 nm at room temperature under UV or blue light excitation, was improved by ∼35% as compared with Sm3+-free samples. This energy transfer was confirmed by faster decay times of Sm3+ as energy donors. Moreover, the energy transfer between Sm3+ and Eu3+ is unidirectional and irreversible, implying that the energy transfer wastage between Sm3+ and Eu3+ is very low. Magnetic susceptibility (χ) measurements of LSEBx were carried out in the temperature range 2-320 K and are used to compare calculated and experimental energy levels.

Structural and luminescence properties of Dy3+ doped bismuth phosphate glasses for greenish yellow light applications

NASA Astrophysics Data System (ADS)

Damodaraiah, S.; Reddy Prasad, V.; Babu, S.; Ratnakaram, Y. C.

2017-05-01

Different compositions of (5, 10, 15 and 20 mol%) of bismuth and different concentrations (0.5, 1.0, 1.5 and 2.0 mol%) of Dy3+ ion doped bismuth phosphate (BiP) glasses were synthesized by melt-quenching technique. The structural characterization was accomplished by XRD, SEM with EDS, FTIR, FT-Raman and 31P MAS NMR spectroscopy. The optical properties were studied using absorption and photoluminescence spectroscopy. Different structural groups were identified using FTIR and FT-Raman spectra. The depolymerization of metaphosphate chains are described by the decrease of Q2 tetrahedral sites allowing the formation of pyrophosphate groups (Q1) revealed by 31P MAS NMR spectroscopic investigations. Judd-Ofelt intensity parameters Ωλ (λ = 2, 4 and 6) were evaluated from absorption spectra. Radiative parameters such as radiative lifetimes (τR), integrated absorption cross-sections (Σ) and branching ratios (βR) were calculated using Judd-Ofelt intensity parameters. From photoluminescence spectra, experimental branching ratios (βexp) and stimulated emission cross-sections (σP) were calculated for all the observed emission transitions of prepared glasses. The decay profiles for 4F9/2 level were recorded and fit exponential for 0.5 mol% and non-exponential for higher concentrations of Dy3+ due to non-radiative energy transfer among excited Dy3+ ions. The CIE chromaticity co-ordinates have been calculated from the luminescence spectra which confirmed greenish yellow light emission.

Structural and luminescence studies on Dy3+ doped lead boro-telluro-phosphate glasses

NASA Astrophysics Data System (ADS)

Selvi, S.; Venkataiah, G.; Arunkumar, S.; Muralidharan, G.; Marimuthu, K.

2014-12-01

This paper reports results obtained on the structural and luminescence properties of Dy3+doped lead boro-telluro-phosphate glasses prepared following the melt quenching technique. FTIR spectra exhibit the presence of B-O vibrations, P-O-P symmetric vibrations and Te-O stretching modes of TeO3 and TeO6 units. The metal-ligand bond was identified through UV-vis-NIR absorption spectra and to determine the band tailing parameter, direct and indirect band gap energy of the prepared glasses. The Judd-Ofelt (JO) intensity parameters (Ω2, Ω4 and Ω6), experimental and theoretical oscillator strengths were also determined and reported. Luminescence measurements were made to determine the transition probability (A), stimulated emission cross-section (σPE) and branching ratio (βR) for the transitions that include 4F9/2→6H11/2, 6H13/2 and 6H15/2 bands. The effect of Dy3+ ion concentration on the intensity ratio of yellow to blue emission bands has also been studied and reported. The lifetime corresponding to the 4F9/2 level of the title glasses has been found to decrease with the increase in Dy3+ ion concentration. The chromaticity coordinates (x,y) have been estimated from the luminescence spectra and the suitability of title glasses for white light applications has been analyzed using CIE chromaticity diagram. The variation of optical properties with the concentration of dysprosium oxide content in the glasses have been studied and reported.

Spectroscopic properties and energy transfer parameters of Er3+- doped fluorozirconate and oxyfluoroaluminate glasses

PubMed Central

Huang, Feifei; Liu, Xueqiang; Hu, Lili; Chen, Danping

2014-01-01

Er3+- doped fluorozirconate (ZrF4-BaF2-YF3-AlF3) and oxyfluoroaluminate glasses are successfully prepared here. These glasses exhibit significant superiority compared with traditional fluorozirconate glass (ZrF4-BaF2-LaF3-AlF3-NaF) because of their higher temperature of glass transition and better resistance to water corrosion. Judd-Ofelt (J-O) intensity parameters are evaluated and used to compute the radiative properties based on the VIS-NIR absorption spectra. Broad emission bands located at 1535 and 2708 nm are observed, and large calculated emission sections are obtained. The intensity of 2708 nm emission closely relates to the phonon energy of host glass. A lower phonon energy leads to a more intensive 2708 nm emission. The energy transfer processes of Er3+ ions are discussed and lifetime of Er3+: 4I13/2 is measured. It is the first time to observe that a longer lifetime of the 4I13/2 level leads to a less intensive 1535 nm emission, because the lifetime is long enough to generate excited state absorption (ESA) and energy transfer (ET) processes. These results indicate that the novel glasses possess better chemical and thermal properties as well as excellent optical properties compared with ZBLAN glass. These Er3+- doped ZBYA and oxyfluoroaluminate glasses have potential applications as laser materials. PMID:24852112

Spectroscopic investigations on Pr³+ and Nd³+ doped strontium-lithium-bismuth borate glasses.

PubMed

Rajesh, D; Balakrishna, A; Seshadri, M; Ratnakaram, Y C

2012-11-01

Spectroscopic investigations on different concentrations (0.1, 0.5, 1.0, 1.5 and 2.0mol%) of Pr(3+) and Nd(3+) doped strontium lithium bismuth borate glasses have been done. X-ray diffraction, SEM with EDS, absorption and luminescence spectra were recorded for all the glass matrices and analyzed. X-ray diffraction profiles and SEM images conformed amorphous nature of investigated glass samples. EDS spectra of host glass and Pr(3+)doped glass matrices gave information about the chemical composition of glass samples. From the absorption spectra of Pr(3+) and Nd(3+) ions, Judd-Ofelt (J-O) intensity parameters (Ω(λ),λ=2, 4 and 6) have been calculated and compared with other glass matrices. The emission characteristics such as radiative lifetimes (τ(R)), measured and calculated branching ratios (β) and stimulated emission cross-sections (σ(P)) have been obtained for the observed emission transitions of Pr(3+) and Nd(3+) ions in the above glass matrix for all the concentrations. From the emission spectra of Pr(3+) and Nd(3+) doped glass matrices, the effect of concentration on the quenching of intensity of (1)D(2)→(3)H(4) transition of Pr(3+) ion and (4)F(3/2)→(4)I(9/2), (4)I(11/2) and (4)I(13/2) transitions of Nd(3+) have been studied and discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

Spectroscopic properties and thermal stability of Er3+ -doped TeO2-B2O3-Nb2O5-ZnO glass for potential WDM amplifier.

PubMed

Xu, Tiefeng; Zhang, Xudong; Li, Guangpo; Dai, Shixun; Nie, Qiuhua; Shen, Xiang; Zhang, Xianghua

2007-06-01

A series of novel 70TeO2-(15-x)B2O3-xNb2O5-15ZnO-1wt.% Er2O3 (TBN x=0, 3, 6, 9, 12 and 15 mol%) tellurite glasses were prepared. The thermal stability, absorption spectra, emission spectra, and the lifetime of the (4)I(13/2) level of Er(3+) ions were measured and investigated. Three Judd-Ofelt intensity parameters Omega(t) (t=2, 4 and 6) (Omega(2)=(5.42-6.76)x10(-20)cm(2); Omega(4)=(1.37-1.73)x10(-20)cm(2); Omega(6)=(0.70-0.94)x10(-20)cm(2)) of Er(3+) ions were calculated by Judd-Ofelt theory. It is found that the Omega(6) first increases with the increase of Nb2O5 content from 0 to 6 mol% and then decreases, which is mainly affected by the number of non-bridging oxygen ions of the glass network. The high peak of stimulated emission cross-section (sigma(e)(peak)=(0.77-0.91)x10(-20)cm(2)) of Er(3+): (4)I(13/2)-->(4)I(15/2) transition were obtained according to McCumber theory and broad full width at half maximum (FWHM=65-73 nm) of the (4)I(13/2)-->(4)I(15/2) transition of Er(3+) ions were measured. The results indicate that these new TBN glasses can be used as a candidate host material for potential broadband optical amplifiers.

Thermal and optical properties of Tm3+ doped tellurite glasses.

PubMed

Ozen, G; Demirata, B; Oveçoğlu, M L; Genç, A

2001-02-01

Ultraviolet, visible (UV/VIS) and differential thermal analysis (DTA) measurements were carried out in order to investigate the optical and thermal properties of various 0.5 mol.% Tm2O3 containing (1 - x)TeO2 + xLiCl glasses in molar ratio. The samples were prepared by fusing the mixture of their respective reagent grade powders in a platinum cricuble at 750 degrees C for 30 min. DTA curves taken in the 23-600 degrees C temperature range with a heating rate of 10 degrees C/min reveal a change in the value of the glass transition temperature, Tg, while melting was not observed for the glasses containing LiCl content less than 50 mol.%. These glasses were found to be moisture-resistant. However, the glasses with LiCl content higher than 50 mol.%, in which a melting peak was observed at Tc = 401 degrees C, were moisture-sensitive. Absorption measurements in the UV/VIS region of the glasses without Tm2O3 content show that the Urbach cutoff occurs at about 320 nm and, is relatively independent of the LiCl content. Six absorption bands were observed in the Tm2O3 doped glasses corresponding to the absorption of the 1G4, 3F2, 3F3 and 3F4, 3H5 and 3H4 levels from the 3H6 ground level of Tm3+ ions. The spectra also show that the integrated absorption cross-section of each band depends on the glass composition. Judd-Ofelt theory was used to determine the Judd-Ofelt parameters as well as the radiative transition probabilities for the metastable levels of Tm3+ ions in (0.3)LiCl + (0.7) TeO2: 0.01 Tm2O3 glass which is moisture-resistant.

Spectroscopic and energy transfer behavior of Dy3+ ions in B2O3sbnd TeO2sbnd PbOsbnd PbF2sbnd Bi2O3sbnd CdO glasses for laser and WLED applications

NASA Astrophysics Data System (ADS)

Arunkumar, S.; Venkataiah, G.; Marimuthu, K.

2015-02-01

A new series of white light emitting Dy3+ doped Lead tellurofluoroborate glasses have been prepared and their spectroscopic and energy transfer behavior were explored through analyzing XRD, FTIR, Raman, SEM, EDAX, optical absorption, photoluminescence and lifetime measurements. The fundamental stretching of the various borate and tellurite networks were identified using FTIR and Raman spectral analysis. The bonding parameter studies reveal the ionic nature of the Dysbnd O bond in the present glasses. The Judd-Ofelt (JO) intensity parameters determined from the absorption spectra have been used to investigate the nature of bonding and symmetry orientation of the Dy-ligand field environment. The luminescence intensity increases with increasing Dy3+ ion concentration up to 0.5 wt%, beyond that luminescence quenching is observed. The JO parameters have been used to determine the transition probability (A), stimulated emission cross-section (σPE), radiative lifetime (τR) and branching ratios (βR) for the different emission transitions from the 4F9/2 excited level. The higher σPE and βR values of the 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 transitions suggest the possible laser action in the visible region. The Y/B ratio, CIE chromaticity color coordinates (x, y) and Color correlated temperature (CCT) were also estimated from the luminescence spectra for different concentration as well as pumping wavelengths. The x, y chromaticity color coordinates fall within the white light region and the white light can be tuned by varying the excitation wavelengths. The lifetime of the 4F9/2 excited state were measured and is found to decrease with increasing Dy3+ ion content. The non-exponential behavior is predominant in higher Dy3+ ion content glasses and is due to the efficient energy transfer between Dy3+sbnd Dy3+ ions. The decay curves were fitted to the Inokuti-Hirayama (IH) model to understand the nature of energy transfer. Among the prepared glasses, 0.5DPTFB glass possesses higher A,βR, σPE, η values and is suggested for lasers and WLED applications.

Rare earth-doped barium gallo-germanate glasses and their near-infrared luminescence properties.

PubMed

Pisarska, Joanna; Sołtys, Marta; Górny, Agata; Kochanowicz, Marcin; Zmojda, Jacek; Dorosz, Jan; Dorosz, Dominik; Sitarz, Maciej; Pisarski, Wojciech A

2018-08-05

Near-infrared luminescence properties of Nd 3+ and Ho 3+ ions in barium gallo-germanate glasses have been reported. Several spectroscopic parameters for Nd 3+ and Ho 3+ ions have been determined from the Judd-Ofelt analysis and absorption/luminescence measurements. Quite large luminescence lifetime, quantum efficiency and stimulated emission cross-section have been obtained for the main 4 F 3/2  →  4 I 11/2 (Nd 3+ ) and 5 I 7  →  5 I 8 (Ho 3+ ) laser transitions of rare earths in barium gallo-germanate glasses. It suggests that barium gallo-germanate glass is promising for near-infrared laser application at emission wavelengths 1064 nm (Nd 3+ ) and 2020 nm (Ho 3+ ). Copyright © 2018 Elsevier B.V. All rights reserved.

Mid-infrared emission and Raman spectra analysis of Er(3+)-doped oxyfluorotellurite glasses.

PubMed

Chen, Fangze; Xu, Shaoqiong; Wei, Tao; Wang, Fengchao; Cai, Muzhi; Tian, Ying; Xu, Shiqing

2015-04-10

This paper reports on the spectroscopic and structural properties in Er(3+)-doped oxyfluorotellurite glasses. The compositional variation accounts for the evolutions of Raman spectra, Judd-Ofelt parameters, radiative properties, and fluorescent emission. It is found that, when maximum phonon energy changes slightly, phonon density plays a crucial role in quenching the 2.7 μm emission generated by the Er(3+):(4)I11/2→(4)I13/2 transition. The comparative low phonon density contributes strong 2.7 μm emission intensity. The high branching ratio (18.63%) and large emission cross section (0.95×10(-20)  cm(2)) demonstrate that oxyfluorotellurite glass contained with 50 mol.% TeO2 has potential application in the mid-infrared region laser.

Enhanced luminescence behaviour of Eu3+ doped heavy metal oxide telluroborate glasses for Laser and LED applications

NASA Astrophysics Data System (ADS)

Pravinraj, S.; Vijayakumar, M.; Marimuthu, K.

2017-03-01

Effect on structural and spectroscopic behaviour caused by the replacement of lead cations with the aluminium cations in the Eu3+ doped heavy metal oxide borophosphate glasses have been studied with the chemical composition (55B2O3+19.5TeO2+10K2O+(15-x)PbO+xAl2O3+0.5Eu2O3 (where x=0, 2.5, 5, 7.5, 10, 12.5 and 15 in wt%) prepared by melt quenching technique. The FTIR and Raman spectral studies reveal the presence of various fundamental vibrational units and are used to identify the phonon energy of the title glasses. The positive values of bonding parameter (δ) indicate the formation of covalent bonds between the dopant (Eu3+) and the anions (O2-). Luminescence spectra of all the titled glasses exhibit five emission bands due to the electronic transitions of the trivalent europium ions. The radiative properties such as transition probability (A), stimulated emission cross-section (σpE) and branching ratio (βR) of the various emission transitions of the Eu3+ ions have been estimated using Judd-Ofelt (JO) theory. The characteristic emission was identified through CIE 1931 color chromaticity diagram and McCamy's formula have been used to estimate the correlated color temperature (CCT) using (x,y) chromaticity coordinates. The luminescence decay profile pertaining to the 5D0 metastable state of the Eu3+ ions exhibits single exponential behaviour uniformly for all the titled glasses and the experimental lifetime values were obtained following the curve fitting method.

Spectroscopic studies of Nd3+ doped lead tungsten tellurite glasses for the NIR emission at 1062 nm

NASA Astrophysics Data System (ADS)

Venkateswarlu, M.; Mahamuda, Sk.; Swapna, K.; Prasad, M. V. V. K. S.; Srinivasa Rao, A.; Mohan Babu, A.; Shakya, Suman; Vijaya Prakash, G.

2015-01-01

Lead Tungsten Tellurite (LTT) glasses doped with different concentrations of Nd3+ ions were prepared by using the melt quenching technique to study the absorption, emission and decay spectral profiles with an aim to understand the lasing potentialities of these glasses. From the absorption spectra, the Judd-Ofelt (J-O) parameters are evaluated and in turn used to calculate the transition probability (AR), total transition probability (AT), radiative lifetime (τR) and branching ratios (βR) for prominent emission levels of Nd3+. The emission spectra recorded for LTT glasses gives three emission transitions 4F3/2 → 4I9/2, 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 for which effective band widths (ΔλP) and stimulated emission cross-sections (σse) are evaluated. Branching ratios (βR) measured for all the LTT glasses show that 4F3/2 → 4I11/2 transition is quite suitable for lasing applications. The intensity of emission spectra increases with increase in the concentrations of Nd3+ up to 1.0 mol% and beyond concentration quenching is observed. Relatively higher emission cross-sections and branching ratios observed for the present LTT glasses over the reported glasses suggests the feasibility of using LTT glasses for infrared laser applications. From the absorption, emission and decay spectral measurements, it was found that 1.0 mol% of Nd3+ ion concentration is aptly suitable for LTT glasses to give a strong NIR laser emission at 1062 nm.

Thermal stability and Judd-Ofelt analysis of optical properties of Sm3+-doped sodium tellurite glasses

NASA Astrophysics Data System (ADS)

Mawlud, Saman Q.; Ameena, Mudhafar M.; Sahar, Md. Rahim; Mahraz, Zahra A. Said; Ahmed, Kasim Fawzy

2017-09-01

Series of glasses based on (70-x) TeO2 - 20Na2O - xSm2O3 (x=0, 0.3, 0.6, 1, 1.2, 1.5 mol%) have been prepared using melt-quenching technique. The nature of the glass has been confirmed using X-ray diffraction; it is found that the glass samples are amorphous in nature. The thermal stability of the glass has been determined by means of Differential Thermal Analysis (DTA). From the DTA curve, the glass transition temperature (Tg), crystallization temperature (Tc) and melting temperature (Tm) have been identified and thermal stability is also calculated. The absorption properties of these samples are obtained by using UV-Visible-NIR spectrometer, the recorded absorption spectra exhibit nine absorption transition bands peaks corresponding to the transitions from ground level 6H5/2→6P3/2, 4I11/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2 and 6F1/2. The emission characteristic of this glass is characterized using Photoluminescence (PL) spectroscopy at excited wavelength 404 nm, the emission spectra consisted of four emission bands at 561.95 nm, 598.69 nm, 643.77 nm and 704.56 nm which were assigned as a transition 4G5/2→6H5/2, 6H7/2, 6H9/2 and 6H11/2 respectively. From f-f intensity model the experimental oscillator strengths, fexp and theoretical oscillator strength fcal were calculated. Using Judd-Ofelt theory and fit process of least square, the phenomenological intensity parameters Ωλ (λ=2,4,6) were obtained, In order to evaluate potential applications of Sm3+ ions in telluride glasses, the spectroscopic parameters: transition probability AR, branching ratio Br, radiative life time τr, emission pick cross section σλ for each band were calculated. The comparative studies with other Sm3+ doped different glasses showed that present glasses could be a potential candidate for lasers.

Structural and optical studies of Er3+-doped alkali/alkaline oxide containing zinc boro-aluminosilicate glasses for 1.5 μm optical amplifier applications

NASA Astrophysics Data System (ADS)

Kaky, Kawa M.; Lakshminarayana, G.; Baki, S. O.; Lira, A.; Caldiño, U.; Meza-Rocha, A. N.; Falcony, C.; Kityk, I. V.; Taufiq-Yap, Y. H.; Halimah, M. K.; Mahdi, M. A.

2017-07-01

In the present work, we report on the optical spectral properties of Er3+-doped zinc boro-aluminosilicate glasses with an addition of 10 mol % alkali/alkaline modifier regarding the fabrication of new optical materials for optical amplifiers. A total of 10 glasses were prepared using melt-quenching technique with the compositions (40-x)B2O3 - 10SiO2 - 10Al2O3 - 30ZnO - 10Li2O - xEr2O3 and (40-x)B2O3 - 10SiO2 - 10Al2O3 - 30ZnO - 10MgO - xEr2O3 (x = 0.1, 0.25, 0.5, 1.0, and 2.0 mol %). We confirm the amorphous-like structure for all the prepared glasses using X-ray diffraction (XRD). To study the functional groups of the glass composition after the melt-quenching process, Raman spectroscopy was used, and various structural units such as triangular and tetrahedral-borates (BO3 and BO4) have been identified. All the samples were characterized using optical absorption for UV, visible and NIR regions. Judd-Ofelt (JO) intensity parameters (Ωλ, λ = 2, 4 and 6) were calculated from the optical absorption spectra of two glasses LiEr 2.0 and MgEr 2.0 (doped with 2 mol % of Er3+). JO parameters for LiEr 2.0 and MgEr 2.0 glasses follow the trend as Ω6>Ω2>Ω4. Using Judd-Ofelt intensity parameters, we obtained radiative probability A (S-1), branching ratios (β), radiative decay lifetimes τrad (μs) of emissions from excited Er+3 ions in LiEr 2.0 and MgEr 2.0 to all lower levels. Quantum efficiency (η) of 4I13/2 and 4S3/2 levels for LiEr 2.0 and MgEr 2.0 with and without 4D7/2 level was calculated using the radiative decay lifetimes τrad. (μs) and measured lifetimes τexp. (μs). We measured the visible photoluminescence under 377 nm excitation for both LiEr and MgEr glass series within the region 390-580 nm. Three bands were observed in the visible region at 407 nm, 530 nm, and 554 nm, as a result of 2H9/2 → 4I15/2, 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions, respectively. Decay lifetimes for emissions at 407 nm, 530 nm, and 554 nm were measured and they show single exponential behavior for all the LiEr and MgEr glass series. From the photoluminescence and radiative decay lifetimes (τrad), we calculated the full-width at half-maximum (FWHM), emission cross-section (σPE) and bandwidth gain (FWHM × σPE) parameters. Near-infrared photoluminescence under 980 nm excitation was measured for all the LiEr and MgEr glass series in the region 1420-1620 nm. NIR emissions show a broadband centered at ∼1530 nm due to the transition of Er3+: 4I13/2 → 4I15/2. Decay lifetimes for NIR emission at ∼1530 nm were measured and they show a quite exponential nature for all the LiEr and MgEr glass series. From the NIR emission spectra and decay lifetimes, we calculated the full-width at half-maximum (FWHM), the emission cross-section (σPE) and the bandwidth gain (FWHM × σPE) for the NIR emission and it shows FWHM of 50-70 nm for prepared glasses, emission cross-section of (∼3.5) × 10-20 cm2, while bandwidth gain was (∼25) × 10-26 cm3.

Optical absorption and photoluminescence properties of Er3+ doped mixed alkali borate glasses.

PubMed

Ratnakaram, Y C; Kumar, A Vijaya; Naidu, D Tirupathi; Rao, J L

2005-07-01

An investigations of the optical absorption and fluorescence spectra of 0.2 mol% Er2O3 in mixed alkali borate glasses of the type 67.8B2O3 x xLi2O(32-x)Na2O, 67.8B2O3 x xLi2O(32-x)K2O and 67.8B2O3 x xNa2O(32-x)K2O (where x = 8, 12, 16, 20 and 24) are presented. The glasses were obtained by quenching melts consisting of H3BO3, Li2CO3, Na2CO3, K2CO3 and Er2O3 (950-1100 degrees C, 1.5-2 h) between two brass plates. Spectroscopic parameters like Racah (E1, E2 and E3), spin-orbit (xi(4f)) and configuration interaction (alpha) parameters are deduced as function of x. Using Judd-Ofelt theory, Judd-Ofelt intensity parameters (omega2, omega4 and omega6) are obtained. Radiative and non-radiative transition rates (A(T) and W(MPR)), radiative lifetimes (tauR), branching ratios (beta) and integrated absorption cross-sections (sigma) have been computed for certain excited states of Er3+ in these mixed alkali borate glasses. Emission spectra have been studied for all the three Er3+ doped mixed alkali borate glasses. The present paper throws light on the trends observed in the intensity parameters, radiative lifetimes, branching ratios and emission cross-sections as a function of x in these borate glasses, keeping in view the effect of mixed alkalies in borate glasses.

Studies on electronic spectral parameters of doped Nd(III) ion with therapeutically important ligands in dioxane solvent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bajaj, Annu, E-mail: annu.bajaj11@gmail.com; Jain, Sushma

2016-05-06

The present investigation is concerened with the studies on electronic spectral parameters viz. Oscillator strength (P), Judd-Ofelt T{sub λ} (λ=2,4,6), Slater-Condon(F{sub K}),Lande(ζ{sub 4F}),Nephelauxetic ratio(β), Bonding parameter (b{sup 1/2}) and Percent covalency parameter (δ%) for Nd(III) ion complexes with the ligands having Nitrogen,Oxygen Sulphur donor sites.The variation in the values of oscillator strength explicitly shows the relative sensitivities of the 4f-4f transition as well as the specific correlation between ligand structures and nature of Nd(III) ligand interaction.

Growth, spectroscopy and continuous-wave laser performance of Nd3+:LiLu0.65Y0.35F4 crystal

NASA Astrophysics Data System (ADS)

Demesh, M. P.; Kurilchik, S. V.; Gusakova, N. V.; Yasukevich, A. S.; Kisel, V. E.; Nizamutdinov, A. S.; Marisov, M. M.; Aglyamov, R. D.; Korableva, S. L.; Naumov, A. K.; Semashko, V. V.; Kuleshov, N. V.

2018-04-01

A mixed fluoride crystal of LiLu0.65Y0.35F4 doped with Nd3+ ions was grown by the Bridgman-Stockbarger method. Polarized absorption and luminescence spectra as well as luminescence lifetime were measured at room temperature. Emission probabilities, branching ratios and radiative lifetime were studied within the Judd-Ofelt theory and the emission cross section spectra were calculated. Efficient continuous wave laser operation was demonstrated with the crystal. A maximum output power of 7.7 W and slope efficiency of 60% were achieved at 1047 nm for the TEM00 mode.

Electronic absorption spectral studies of Pr(III) chelates with some amino acids

NASA Astrophysics Data System (ADS)

Kachhawa, Chanchal; Solanki, Kanika; Bhandari, H. S.

2018-05-01

Investigations on Pr(III) systems with 1:1 metal-ligand stoichiometric ratio have been carried out in different solvents. β - Alanine, Taurine and anthranilic acid have been opted as ligands for the investigations. The Study is based on doped crystal phenomenon. The Slater-Condon, spin-orbit, nephelauxetic, bonding, Racah and Judd-Ofelt parameters have been explored during the study. Four bands for Pr(III) have been observed and recorded in the region 350 nm to 900nm. Partial regression method has been used for calculations. Use of computational chemistry has been explored in order to develop better and easier methods of calculations.

Structural, optical absorption and photoluminescence spectral studies of Sm3+ ions in Alkaline-Earth Boro Tellurite glasses

NASA Astrophysics Data System (ADS)

Siva Rama Krishna Reddy, K.; Swapna, K.; Mahamuda, Sk.; Venkateswarlu, M.; Srinivas Prasad, M. V. V. K.; Rao, A. S.; Prakash, G. Vijaya

2018-05-01

Sm3+ ions doped Alkaline-Earth Boro Tellurite (AEBT) glasses were prepared by using conventional melt quenching technique and characterized using the spectroscopic techniques such as FT-IR, optical absorption, emission and decay spectral measurements to understand their utility in optoelectronic devices. From absorption spectra, the bonding parameters, nephelauxetic ratios were determined to know the nature of bonding between Sm3+ ions and its surrounding ligands. From the measured oscillator strengths, the Judd-Ofelt (J-O) intensity parameters were evaluated and in turn used to estimate various radiative parameters for the fluorescent levels of Sm3+ ions in AEBT glasses. The PL spectra of Sm3+ ions exhibit three emission bands corresponding to the transitions 4G5/2 → 6H5/2, 6H7/2 and 6H9/2 in the visible region for which the emission cross-sections and branching ratios were evaluated. The decay spectral profiles measured for 4G5/2 → 6H7/2 transition showed single exponential for lower concentration and non-exponential for higher concentration of doped rare earth ion in the as prepared glasses. Conversion of decay spectral profiles from single to non-exponential have been analyzed using Inokuti-Hirayama (I-H) model to understand the energy transfer mechanism involved in the decay process. CIE Chromaticity coordinates were measured using emission spectral data to identify the exact region of emission from the as-prepared glasses. From the evaluated radiative parameters, emission cross-sections and quantum efficiencies, it was observed that AEBT glass with 1 mol% of Sm3+ ions is more suitable for designing optoelectronic devices.

Spectroscopic studies of Sm3+ ions activated lithium lead alumino borate glasses for visible luminescent device applications

NASA Astrophysics Data System (ADS)

Deopa, Nisha; Rao, A. S.

2017-10-01

Photoluminescence (PL) characterization of Lithium Lead Alumino Borate (LiPbAlB) glasses doped with Sm3+ ions at varying concentrations have been studied by using absorption, excitation, emission, time resolved and confocal image measurements. From the absorption spectra, Judd-Ofelt (J-O) intensity parameters were evaluated and in turn used to estimate various radiative parameters for the fluorescent levels of Sm3+ ion doped LiPbAlB glasses. The PL spectra of Sm3+ ions exhibit three emission bands corresponding to the transitions 4G5/2 → 6H5/2, 6H7/2 and 6H9/2, for which the emission cross-sections and branching ratios were evaluated to know the potentialities of these materials as visible luminescent devices. The decay spectral profiles measured for 4G5/2 → 6H7/2 transition level were used to estimate quantum efficiency of the as-prepared glasses. The non-exponential decay curves observed for higher Sm3+ ion concentrations were well fitted to Inokuti-Hirayama model to understand the predominant energy transfer mechanism involved in the as-prepared glasses. CIE chromaticity coordinates and correlated color temperatures (CCT) were evaluated to understand the utility of the titled glasses in cool white light generation. The confocal images captured under 405 nm CW laser excitation show intense reddish-orange color. From the evaluated radiative parameters, emission cross-sections, quantum efficiency, CIE co-ordinates, CCT temperatures and confocal images, it was observed that LiPbAlB glass with 0.5 mol% Sm3+ ions are more suitable for w-LEDs and reddish-orange luminescent device applications.

Spectroscopic study of Pr3+ ions doped Zinc Lead Tungsten Tellurite glasses for visible photonic device applications

NASA Astrophysics Data System (ADS)

Sharma, Ritu; Rao, A. S.; Deopa, Nisha; Venkateswarlu, M.; Jayasimhadri, M.; Haranath, D.; Prakash, G. Vijaya

2018-04-01

Zinc Lead Tungsten Tellurite (ZnPbWTe) glasses doped with different Pr3+ ion concentrations having the composition 5ZnO + 15PbO + 20WO3 + (60-x)TeO2 + xPr6O11 (where x = 0.5, 1, 1.5, 2.0 and 2.5 mol%) were prepared by using sudden quenching technique and characterized to understand their visible emission characteristic features using spectroscopic techniques such as absorption, excitation and emission. The Judd-Ofelt (J-O) theory has been applied to the absorption spectral features with an aim to evaluate various radiative properties for the prominent fluorescent levels of Pr3+ions in the as-prepared glasses. The emission spectra recorded for the as-prepared glasses under 468 nm excitation show three prominent emission transitions 3P0→3H6, 3P0→3F2 and 3P1→3F4, of which 3P0→3F2 observed in visible red region (648 nm), is relatively more intense. The intensity of 3P0→3F2 emission transition in the titled glasses increases up to 1mol% of Pr3+ ions and beyond concentration quenching is observed. Branching ratios (βR) and emission cross-sections (σse) were estimated for 3P0→3F2 transition to understand the luminescence efficiency in visible red region (648 nm). The CIE chromaticity coordinates were also evaluated in order to understand the suitability of these glasses for visible red luminescence devices. From the emission cross-sections, quantum efficiency and CIE coordinates, it was concluded that 1mol% of Pr3+ ions in ZnPbWTe glasses are quite suitable for preparing visible reddish orange luminescent devices.

Spectroscopic analysis and efficient diode-pumped 2.0 μm emission in Ho3+/Tm3+ codoped fluoride glass

NASA Astrophysics Data System (ADS)

Tian, Ying; Jing, Xufeng; Xu, Shiqing

2013-11-01

Intense 2.0 μm emission has been obtained in Ho3+/Tm3+ codoped ZBLAY glass pumped by common laser diode. Three intensity parameters and radiative properties have been determined from the absorption spectrum based on the Judd-Ofelt theory. The 2 μm emission characteristics and the energy transfer mechanism upon excitation of a conventional 800 nm laser diode are investigated. Efficient Tm3+ to Ho3+ energy transfer processes have been observed in present glass and investigated using steady-state and time-resolved optical spectroscopy measurement. The energy transfer microscopic parameter has been calculated with the Inokuti-Hirayama and Förster-Dexter models. High quantum efficiency of 2 μm emission (80.35%) and large energy transfer coefficient from Tm3+ to Ho3+ indicates this Ho3+/Tm3+ codoped ZBLAY glass is a promising material for 2.0 μm laser.

Photofunctional Eu3+/Tb3+ hybrids through sulfoxide linkages: coordination bonds construction, characterization and luminescence.

PubMed

Guo, Lei; Yan, Bing; Liu, Jin-Liang

2011-05-14

New kinds of organic-inorganic hybrid materials consisting of rare earth (Eu(3+), Tb(3+)) complexes covalently bonded to a silica-based network have been obtained by a sol-gel approach. Three novel versatile molecular building blocks containing sulfoxide organic units have been synthesized by methylene modification reaction, which are used as the ligands of rare earth ions and also as siloxane network precursors. The obtained hybrids are characterized by chemical analysis and spectroscopic methods such as FTIR and UV; XRD and SEM. Photoluminescence measurements on the prepared hybrids were performed showing the intra-4f(n) emission in the visible (Eu(3+), Tb(3+)) region and in all the cases being sensitized by the sulfoxide ligands. The emission quantum efficiency and the Judd-Ofelt intensity parameters of Eu(3+) hybrid materials were also investigated in detail.

Synthesis and near-infrared fluorescence of K5NdLi2F10 nanocrystals and their dispersion with high doping concentration and long lifetime.

PubMed

Duan, Weikuan; Zhang, Yanyan; Wang, Zhongyue; Jiang, Jingyi; Liang, Chen; Wei, Wei

2014-06-07

K5NdLi2F10 nanocrystals were synthesized by a novel synthetic route in the liquid phase, which could improve the morphology and reduce the size effectively, for the first time. The luminescence intensities of the K5NdLi2F10 nanocrystals and their dispersion in polyethylene glycol 400 (PEG-400) approximate to that of neodymium doped phosphate glass (3 mol%), while the lifetimes of the nanocrystals alone and when dispersed with Nd(3+) ions (1 × 10(20) cm(-3)) are 303.4 μs and 174.6 μs respectively. Based on the Judd-Ofelt analysis, the emission quantum yield of the dispersion reaches 39.57%. In all, the K5NdLi2F10 nanocrystals and their dispersion have promising applications as liquid laser materials and biological fluorescent markers.

Optical spectroscopy, 1.06 μm emission properties of Nd3 +-doped phosphate based glasses

NASA Astrophysics Data System (ADS)

Sk. Nayab, Rasool; Sasikala, T.; Mohan Babu, A.; Rama Moorthy, L.; C. K., Jayasankar

2017-06-01

Neodymium doped phosphate based glasses with composition of (P2O5 + K2O + Al2O3 + CaF2) were prepared. The samples were analysed through differential thermal analysis (DTA), Fourier transform infrared (FTIR), absorption, emission and decay measurements. Judd-Ofelt parameters (Ωλ) have been determined from the spectral intensities of absorption bands in order to calculate the radiative parameters like radiative transition probabilities (AR), radiative lifetime (τR) and branching ratios (βR) for the 4F3/2 → 4I11/2 laser transition of Nd3 + ion. The effective emission bandwidths (Δλeff), experimental branching ratios (βexp) and stimulated emission cross-sections (σe) have been determined from the emission spectrum. The decay curves of the 4F3/2 level exhibited almost single exponential nature for all the Nd3 + ion concentrations.

Optical property investigations of polystyrene capped Ca{sub 2}P{sub 2}O{sub 7}:Dy{sup 3+} persistent phosphor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jain, Abhilasha, E-mail: abhilasha.vnit@gmail.com; Kumar, Ashwini; Dhoble, S.J

2015-10-15

Highlights: • Synthesis of polymer capped pyrophosphate phosphors by citrate gel method. • Radiative lifetime is calculated from parameters of Judd-Ofelt theory and ICP-AES. • Reaction mechanism is discussed leading to high photoluminescence efficiency. • PL emission spectrum reveals broad band emission suitable for solid state lighting. - Abstract: By virtue of enhanced photosensivity, good optical response and better thermal stability, organic–inorganic hybrid materials are contemplated as one of the alternatives for designing advanced optoelectronic devices and innovative photonic applications. A novel inorganic organic hybrid Ca{sub 2}P{sub 2}O{sub 7}:Dy{sup 3+} phosphor has been fabricated by Pechini method. The optical propertymore » of synthesized phosphor is successfully altered by the in corporation of polystyrene sulfonic acid as capping agent in the colloidal solution. The phase purity and the average particle size of the prepared phosphor were calculated from X-ray diffraction (XRD) employing Debye Scherrer method. The morphological and chemical investigations were carried out through scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analysis. The radiative transitions are explained on the basis of Judd-Ofelt theory and on the basis of derived parameters, the radiative lifetime of persistent hybrid Ca{sub 2}P{sub 2}O{sub 7}:Dy{sup 3+} phosphor is calculated as 5.33 ms. This paper explores the mechanism leading to high photoluminescence efficiency using organic capping additives. The photoluminescence (PL) graphs reveal broad band emission at 482 nm (blue) and 573 nm (yellow) corresponding to {sup 4}F{sub 9/2}-{sup 6}H{sub 15/2} and {sup 4}F{sub 9/2}-{sup 6}H{sub 13/2} transitions of Dy{sup 3+}, respectively. The Commission International De I-Eclairage (CIE) chromaticity co-ordinates were calculated from emission spectra and the values (x, y) were approaching to standard value of white emission. The synthesized pyrophosphate phosphors can thereby account in multiple potential applications including white light emitting diodes.« less

∼2 μm emission properties and non-radiative processes of Tm{sup 3+} in germanate glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Song; Liu, Xueqiang; Fan, Xiaokang

2014-11-07

In this paper, 80GeO{sub 2}-8Ga{sub 2}O{sub 3}-10BaO-2Nb{sub 2}O{sub 5}-6PbO (in mol%) glass samples with different Tm{sub 2}O{sub 3} concentrations (0, 0.5, 0.75, 1, 1.25, and 1.5 mol. %) were prepared by traditional melt-quenching method. According to the measurement of thermal properties of the host glass, the glass transition temperature is 596.7 °C and no crystallization peak is observed. Judd–Ofelt parameters Ω{sub t} (t = 2, 4, 6) and fluorescent lifetimes were obtained by Judd-Ofelt theory. The similar values of Judd–Ofelt parameters and the full-width at half-maximums of ∼1800 nm indicate the local environment of Tm{sup 3+} changes little with increment of Tm{sub 2}O{sub 3} concentrations.more » Maximum stimulated emission cross-section of ∼1800 nm is 6.22 × 10{sup −21} cm{sup 2} as calculated by Fuchtbauer–Ladenburg formula. Energy migration among Tm{sup 3+} ions was analyzed by the extended overlap integral method. The non-radiative transition rates between mainly energy levels of Tm{sup 3+} were calculated. Non-radiative transition rate of {sup 3}F{sub 4} energy level caused by OH was analyzed by rate equation and deduced by fitting the fluorescence decay curve.« less

Gamma-radiation effects on luminescence properties of Eu3+ activated LaPO4 phosphor

NASA Astrophysics Data System (ADS)

Vujčić, Ivica; Gavrilović, Tamara; Sekulić, Milica; Mašić, Slobodan; Putić, Slaviša; Papan, Jelena; Dramićanin, Miroslav D.

2018-05-01

Eu3+ activated LaPO4 phosphors were prepared by a high-temperature solid-state method and irradiated to different high-doses gamma-radiation in the 0-4 MGy range. No effects of high-doses of high-energy radiation on phosphor's morphology and structure were observed, as documented by electron microscopy and X-ray diffraction measurements. On the other hand, photoluminescence measurements showed that emission properties of phosphor were affected by gamma-radiation; changes in radiative properties being prominent for absorbed radiation doses up to 250 kGy after which no additional changes are observed. Judd-Ofelt analysis of emission spectra is performed to thoroughly investigate radiative properties of phosphors. Analysis showed that radiative transition probability of Eu3+ emission decreases while non-radiative probability increases upon gamma-irradiation. Quantum efficiency of emission is decreased from about 46% to 35% when Eu3+ doped LaPO4 powders are exposed to gamma-radiation of 250 kGy dose, showing no additional decrease for higher gamma-radiation doses.

Computation of energy interaction parameters as well as electric dipole intensity parameters for the absorption spectral study of the interaction of Pr(III) with L-phenylalanine, L-glycine, L-alanine and L-aspartic acid in the presence and absence of Ca 2+ in organic solvents

NASA Astrophysics Data System (ADS)

Moaienla, T.; Singh, Th. David; Singh, N. Rajmuhon; Devi, M. Indira

2009-10-01

Studying the absorption difference and comparative absorption spectra of the interaction of Pr(III) and Nd(III) with L-phenylalanine, L-glycine, L-alanine and L-aspartic acid in the presence and absence of Ca 2+ in organic solvents, various energy interaction parameters like Slater-Condon ( FK), Racah ( Ek), Lande factor ( ξ4f), nephelauxetic ratio ( β), bonding ( b1/2), percentage-covalency ( δ) have been evaluated applying partial and multiple regression analysis. The values of oscillator strength ( P) and Judd-Ofelt electric dipole intensity parameter Tλ ( λ = 2, 4, 6) for different 4f-4f transitions have been computed. On analysis of the variation of the various energy interaction parameters as well as the changes in the oscillator strength ( P) and Tλ values reveal the mode of binding with different ligands.

Growth and spectroscopic properties of Sm3+:KY(WO4)2 crystal

NASA Astrophysics Data System (ADS)

Demesh, M. P.; Dernovich, O. P.; Gusakova, N. V.; Yasukevich, A. S.; Kornienko, A. A.; Dunina, E. B.; Fomicheva, L. A.; Pavlyuk, A. A.; Kuleshov, N. V.

2018-01-01

A Sm3+:KY(WO4)2 crystal was grown by the modified Czochralski technique. Polarized absorption and fluorescence spectra, as well as a fluorescence decay curve, were recorded at room temperature. Radiative properties such as emission probabilities, branching ratios and radiative lifetimes were investigated within the framework of the Judd-Ofelt theory as well as the theory of f-f transition intensities which takes into account the influence of the excited configurations. Emission cross section spectra were determined. 4G5/2 fluorescence decay was analyzed within the framework of the Inokuti-Hirayama model. The spectroscopic properties of Sm:KYW crystal were compared with those of other Sm3+-doped materials.

Highly-efficient mid-infrared CW laser operation in a lightly-doped 3 at.% Er:SrF2 single crystal.

PubMed

Su, Liangbi; Guo, Xinsheng; Jiang, Dapeng; Wu, Qinghui; Qin, Zhipeng; Xie, Guoqiang

2018-03-05

3 at.% Er:SrF 2 laser crystals with high optical quality were successfully grown using the temperature gradient technique (TGT). The intense mid-infrared emission was observed around 2.7 μm with excitation by a 970 nm LD. Based on the Judd-Ofelt theory, the emission cross-sections of the 4 I 13/2 - 4 I 11/2 transition were calculated by using the Fuchtbauer-Ladenburg (FL) method. Efficient continuous-wave laser operation at 2.8 µm was achieved with the lightly-doped 3 at.% Er:SrF 2 crystal pumped by a 970 nm laser diode. The laser output power reached up to 1.06 W with a maximum slope efficiency of 26%.

Characterization of emission properties of Er3+ ions in TeO2-CdF2-WO3 glasses.

PubMed

Bilir, G; Mustafaoglu, N; Ozen, G; DiBartolo, B

2011-12-01

TeO(2)-CdF(2)-WO(3) glasses with various compositions and Er(3+) concentrations were prepared by conventional melting method. Their optical properties were studied by measuring the absorption, luminescence spectra and the decay patterns at room temperature. From the optical absorption spectra the Judd-Ofelt parameters (Ω(t)), transition probabilities, branching ratios of various transitions, and radiative lifetimes were calculated. The absorption and emission cross-section spectra of the (4)I(15/2) to (4)I(13/2) transition of erbium were determined. Emission quantum efficiencies and the average critical distance R(0) which provides a measure for the strength of cross relaxation were determined. Copyright © 2011 Elsevier B.V. All rights reserved.

Luminescence properties of Eu3+-doped SiO2-LiYF4 glass-ceramic microrods

NASA Astrophysics Data System (ADS)

Secu, C. E.; Secu, M.

2015-09-01

Photoluminescence properties of the glass-ceramics microrods containing Eu3+-doped LiYF4 nanocrystals have been studied and characterized. Judd-Ofelt parameters and quantum efficiency has been computed from luminescence spectra and discussed by comparison to the glass ceramic bulk and pellet. The radiative decay rate Arad is higher in the glass ceramic rods (221 s-1) than in the glass ceramic bulk (130 s-1) but the quantum efficiency computed is very low (21%) compared to the glass-ceramic bulk (97%). There are effective non-radiative decay channels that might be related to an influence of the dimensional constraints imposed by the membrane pores during xerogel formation and subsequent glass ceramization.

Crystal growth, polarized spectroscopy and Judd-Ofelt analysis of Tb:YAlO3.

PubMed

Liu, Bin; Shi, Jiaojiao; Wang, Qingguo; Tang, Huili; Liu, Junfang; Zhao, Hengyu; Li, Dongzhen; Liu, Jian; Xu, Xiaodong; Wang, Zhanshan; Xu, Jun

2018-07-05

Tb 3+ -doped YAlO 3 (YAP) single crystal was grown by Czochralski (Cz) method. Based on the polarized absorption spectra, the spectroscopic parameters were calculated to be Ω 2 =3.49×10 -20 cm 2 , Ω 4 =5.87×10 -20 cm 2 and Ω 6 =2.55×10 -20 cm 2 , and then the spontaneous transition rate, fluorescent branching ratio and radiative lifetime of 5 D 4 multiplet were obtained. The yellow emission cross sections of 5 D 4 → 7 F 4 transition were calculated to be 1.72×10 -22 cm 2 , 2.73×10 -22 cm 2 and 2.65×10 -22 cm 2 for a, b and c polarization, respectively. The fluorescence lifetime of the 5 D 4 multiplet was fitted to be 1.72ms. All the data indicate that Tb:YAP crystal is a promising candidate for yellow laser operation. Copyright © 2018. Published by Elsevier B.V.

Optical spectroscopy, 1.06μm emission properties of Nd3+-doped phosphate based glasses.

PubMed

Sk Nayab, Rasool; T, Sasikala; A, Mohan Babu; L, Rama Moorthy; C K, Jayasankar

2017-06-05

Neodymium doped phosphate based glasses with composition of (P 2 O 5 +K 2 O+Al 2 O 3 +CaF 2 ) were prepared. The samples were analysed through differential thermal analysis (DTA), Fourier transform infrared (FTIR), absorption, emission and decay measurements. Judd-Ofelt parameters (Ω λ ) have been determined from the spectral intensities of absorption bands in order to calculate the radiative parameters like radiative transition probabilities (A R ), radiative lifetime (τ R ) and branching ratios (β R ) for the 4 F 3/2 → 4 I 11/2 laser transition of Nd 3+ ion. The effective emission bandwidths (Δλ eff ), experimental branching ratios (β exp ) and stimulated emission cross-sections (σ e ) have been determined from the emission spectrum. The decay curves of the 4 F 3/2 level exhibited almost single exponential nature for all the Nd 3+ ion concentrations. Copyright © 2017 Elsevier B.V. All rights reserved.

Excited-state absorption and fluorescence dynamics of Er3+:KY3F10

NASA Astrophysics Data System (ADS)

Labbé, C.; Doualan, J. L.; Moncorgé, R.; Braud, A.; Camy, P.

2018-05-01

We report here on a complete investigation of the excited-state absorption and fluorescence dynamics of Er3+ doped KY3F10 single crystals versus dopant concentrations and optical excitation conditions. Radiative and effective (including non-radiative relaxations) emission lifetimes and branching ratios are determined from a Judd-Ofelt analysis of the absorption spectra and via specific fluorescence experiments using wavelength selective laser excitations. Excited-state absorption and emission spectra are registered within seven spectral domains, i.e. 560 nm, 650 nm, 710 nm, 810 nm, 970 nm, 1550 nm and 2750 nm. A maximum gain cross-section of 0.93 × 10-21 cm2 is determined at the potential laser wavelength of 2.801 μm for a population ratio of 0.48. Saturation of fluorescence intensities and variations of population ratios versus pumping rates are registered and confronted with a rate equation model to derive the rates of the most important up-conversion and cross-relaxation energy transfers occurring at high dopant concentrations.

Emission analysis of RE3+ (RE = Sm, Dy):B2O3-TeO2-Li2O-AlF3 glasses.

PubMed

Raju, C Nageswara; Sailaja, S; Kumari, S Pavan; Dhoble, S J; Kumar, V Ramesh; Ramanaiah, M V; Reddy, B Sudhakar

2013-01-01

This article reports on the optical properties of 0.5% mol of Sm(3+), Dy(3+) ion-doped B2O3-TeO2-Li2O-AlF3 (LiAlFBT) glasses. The glass samples were characterized by optical absorption and emission spectra. Judd-Ofelt theory was applied to analyze the optical absorption spectra and calculate the intensity parameters and radiative properties of the emission transitions. The emission spectra of Sm(3+) and Dy(3+):LiAlFBT glasses showed a bright reddish-orange emission at 598 nm ((4)G5/2 → (6)H7/2) and an intense yellow emission at 574 nm ((4)F9/2 → (6)H13/2), respectively. Full width at half maximum (FWHM), stimulated emission cross section, gain bandwidth and optical gain values were also calculated to extend the applications of the Sm(3+) and Dy(3+):LiAlFBT glasses. Copyright © 2012 John Wiley & Sons, Ltd.

Optical spectroscopy of BaY2F8:Dy3+

NASA Astrophysics Data System (ADS)

Parisi, Daniela; Toncelli, Alessandra; Tonelli, Mauro; Cavalli, Enrico; Bovero, Enrico; Belletti, Alessandro

2005-05-01

The optical spectra of the BaY2F8:Dy3+ laser crystal have been investigated in the 5000-30 000 cm-1 range. The Judd-Ofelt parametrization scheme has been applied to the analysis of the room temperature absorption spectra. The calculated radiative lifetime of the 4F9/2 state is 1.48 ms. Decay curves of the visible emission have been measured as a function of the temperature for two different Dy3+ concentrations (0.5 and 4.4%). In the case of the diluted crystal the emission profiles are single exponential with decay times consistent with the radiative lifetime. The decay curves of the concentrated crystal are not exponential and they obey the Inokuti-Hirayama model for energy transfer for an electric dipole-dipole interaction in the absence of diffusion among the donors. The emission cross section at 575 nm has been estimated using the integral β-τ method in order to assess the potentialities of this compound as a solid state laser material in the yellow region.

The effect of La2O3 in Tm3+-doped germanate-tellurite glasses for ~2 μm emission

PubMed Central

Peng, Ya-Pei; Yuan, Xinqiang; Zhang, Junjie; Zhang, Long

2014-01-01

A germanate-tellurite glass (GeO2-TeO2-K2O-Nb2O5-La2O3) with thulium doping has been investigated for application as a laser material around 2.0 μm regions. Under the 808 nm laser diode pumped, intense 1.8 μm emission is obtained. Based on the absorption spectra, radiative properties are predicted using Judd-Ofelt theory. The maximum value of emission cross-section of Tm3+ around 1.8 μm can reach 1.46 × 10−20 cm2, which indicated that the germanate-tellurite glass may provide high gain as a good medium for efficient 1.8 μm laser system. PMID:24918516

Growth and spectroscopic properties of Tm3+:NaBi(MoO4)2 single crystal

NASA Astrophysics Data System (ADS)

Gusakova, N. V.; Mudryi, A. V.; Demesh, M. P.; Yasukevich, A. S.; Pavlyuk, A. A.; Kornienko, A. A.; Dunina, E. B.; Khodasevich, I. A.; Orlovich, V. A.; Kuleshov, N. V.

2018-06-01

In this work we report the spectroscopic properties of Tm3+:NaBi(MoO4)2 crystals with the dopant concentrations of 0.7 at.% and 3 at.%. The energy levels of the Tm3+ in the NaBi(MoO4)2 host were determined from polarized optical absorption and photoluminescence spectra measured at 77.4 K. Radiative properties of the crystals were calculated in context of Judd-Ofelt theory. Raman spectra of the crystal were studied. The concentration dependences of emission decay times of 3H4 and 3F4 levels were analyzed. The potential of the crystal for building tunable and ultrafast pulse lasers is shown on the base of cross sections and gain coefficient in the range of 1.9 μm.

Optical absorption and gamma-radiation-shielding parameter studies of Tm3+-doped multicomponent borosilicate glasses

NASA Astrophysics Data System (ADS)

Lakshminarayana, G.; Sayyed, M. I.; Baki, S. O.; Lira, A.; Dong, M. G.; Kaky, Kawa M.; Kityk, I. V.; Mahdi, M. A.

2018-05-01

Different concentrations (0.1‒2.0 mol%) of Tm3+-doped multicomponent borosilicate glasses with 10 mol% Li2O (alkali) or MgO (alkaline) have been synthesized and their optical absorption and radiation shielding features were studied. For both Li2O and MgO series 0.5 mol% Tm3+-doped glass samples, the evaluated Ωλ ( λ = 2, 4, and 6) Judd-Ofelt (JO) intensity parameters from experimental oscillator strengths were used in estimating the radiative transition probabilities ( A R), branching ratios ( β R), and radiative lifetimes ( τ R) for several emission transitions. Using the XCOM software, the mass attenuation coefficients ( µ/ ρ) for all the fabricated glasses were evaluated within the 0.015‒10 MeV energy range. Also, the ( µ/ ρ) values were calculated at 0.356, 0.662, 1.173, and 1.33 MeV photon energies by MCNP5 simulation code and the results were compared with those obtained by XCOM. The ( µ/ ρ) values for Li2O, as well as MgO series glasses, increase with the addition of Tm2O3 and these values for MgO series glasses are slightly higher with respect to Li2O series glasses. From the ( µ/ ρ) values, effective atomic number ( Z eff), half-value layer (HVL), and mean free path (MFP) were calculated and the HVL and MFP results revealed that high-energy photons have more penetration into a glass sample compared to low-energy photons. Further, geometric progression (GP) fitting method was utilized to calculate the exposure buildup factor (EBF) within the 0.015‒15 MeV energy range. The 2.0 mol% Tm2O3-doped glasses show a better ability to attenuate gamma-rays in comparison to other glass samples, so the addition of Tm2O3 content leads to improvement of the shielding efficiency of the prepared glasses.

Compositional dependence of red luminescence from Eu3+ ions doped single and mixed alkali fluoro tungsten tellurite glasses

NASA Astrophysics Data System (ADS)

Annapurna Devi, C. h. B.; Mahamuda, Sk.; Swapna, K.; Venkateswarlu, M.; Srinivasa Rao, A.; Vijaya Prakash, G.

2017-11-01

Trivalent europium ions doped single and mixed alkali fluoro tungsten tellurite glasses have been prepared via melt quenching method and characterized by using Raman, optical absorption, excitation, emission and time resolved spectral measurements to understand their utility in visible red emission. Raman spectrum is used to identify different functional groups present in the as prepared glasses. The optical absorption spectra recorded for all the glasses show six bands corresponding to the transitions 7F0→6D2, 7F0→6D1, 7F1→6D1, 7F0→6D0, 7F0→7F6, and 7F1→7F6. An excitation spectrum is used to measure the electron-phonon coupling strength 'g' and phonon energy of the glass host 'hω'. The photoluminescence (PL) spectra measured under 464 nm excitation show eight luminescence peaks related to the transitions 5D1→7F0 (509 nm), 5D1→7F1 (537 nm), 5D1→7F2 (556 nm), 5D0→7F0 (580 nm), 5D0→7F1 (592 nm), 5D0→7F2 (614 nm), 5D0→7F3 (652 nm) and 5D0→7F4 (701 nm) in all the glasses under investigation. Utilizing the Judd-Ofelt (J-O) parameters evaluated from the PL spectra, various radiative properties have been evaluated. From the decay spectra, experimental lifetimes were measured which are in turn used to evaluate the quantum efficiencies and non-radiatve decay rates in the as prepared glasses. The branching ratios, stimulated emission cross-section, quantum efficiency, colour co-ordinates and confocal images captured to confirm the suitability of these glasses for visible red luminescent devices.

Tm3+/Yb3+ co-doped tellurite glass with silver nanoparticles for 1.85 μm band laser material

NASA Astrophysics Data System (ADS)

Huang, Bo; Zhou, Yaxun; Cheng, Pan; Zhou, Zizhong; Li, Jun; Jin, Wei

2016-10-01

Tm3+/Yb3+ co-doped tellurite glasses with different silver nanoparticles (Ag NPs) concentrations were prepared using the conventional melt-quenching technique and characterized by the UV/Vis/NIR absorption spectra, 1.85 μm band fluorescence emission spectra, transmission electron microscopy (TEM) images, differential scanning calorimeter (DSC) curves and X-ray diffraction (XRD) patterns to investigate the effects of Ag NPs on the 1.85 μm band spectroscopic properties of Tm3+ ions, thermal stability and structural nature of glass hosts. Under the excitation of 980 nm laser diode (LD), the 1.85 μm band fluorescence emission of Tm3+ ions enhances significantly in the presence of Ag NPs with average diameter of ∼8 nm and local surface Plasmon resonance (LSPR) band of ∼590 nm, which is mainly attributed to the increased local electric field induced by Ag NPs at the proximity of doped rare-earth ions on the basis of energy transfer from Yb3+ to Tm3+ ions. An improvement by about 110% of fluorescence intensity is observed in the Tm3+/Yb3+ co-doped tellurite glass containing 0.5 mol% amount of AgNO3 while the prepared glass samples possess good thermal stability and amorphous structural nature. Meanwhile, the Judd-Ofelt intensity parameters Ωt (t = 2,4,6), spontaneous radiative transition probabilities, fluorescence branching ratios and radiative lifetimes of relevant excited levels of Tm3+ ions were determined based on the Judd-Ofelt theory to reveal the enhanced effects of Ag NPs on the 1.85 μm band spectroscopic properties, and the energy transfer micro-parameters and phonon contribution ratios were calculated based on the non-resonant energy transfer theory to elucidate the energy transfer mechanism between Yb3+ and Tm3+ ions. The present results indicate that the prepared Tm3+/Yb3+ co-doped tellurite glass with an appropriate amount of Ag NPs is a promising lasing media applied for 1.85 μm band solid-state lasers and amplifiers.

Optical study of Tm-doped solid solution (Sc0.5Y0.5)2SiO5 crystal

NASA Astrophysics Data System (ADS)

Shi, Jiaojiao; Liu, Bin; Zheng, Lihe; Wang, Qingguo; Tang, Huili; Liu, Junfang; Su, Liangbi; Wu, Feng; Zhao, Hengyu; He, Nuotian; Li, Na; Li, Qiu; Guo, Chao; Xu, Jun; Yang, Kejian; Xu, Xiaodong; Ryba-Romanowski, Witold; Lisiecki, Radosław; Solarz, Piotr

2018-04-01

Tm-doped (Sc0.5Y0.5)2SiO5 (SYSO) crystals were grown by Czochralski method. The UV-VIR-NIR absorption spectra and the near-infrared emission spectra were measured and analysed by the Judd-Ofelt approach. Temperature influence on both absorption and emission spectra has been determined from the data recorded at room temperature and 10 K. It has been found that the structural disorder resulting from dissimilar ionic radii of Sc3+ and Y3+ in the solid solution (Sc0.5Y0.5)2SiO5 crystal brings about a strong inhomogeneous broadening of Tm3+ ions spectra. However, it affects the excited state relaxation dynamics inherent to thulium-doped Y2SiO5 and Sc2SiO5 hosts weakly.

Enhanced frequency upconversion in Er3+-Yb3+ codoped heavy metal oxides based tellurite glasses.

PubMed

Azam, Mohd; Rai, Vineet Kumar

2018-01-24

The spectroscopic investigations on the Er 3+ /Yb 3+ ions doped/codoped TeO 2 -ZnO (TZ), TeO 2 -ZnO-WO 3 (TZW) and TeO 2 -ZnO-WO 3 -TiO 2 (TZWTi) heavy metal oxide (HMO) glasses have been made. The absorption, photoluminescence, decay curve and Judd-Ofelt analysis have been performed to optimise the optical properties of the Er 3+ /Yb 3+ ions. The effect of incorporation of HMOs like WO 3 and TiO 2 in the Er 3+ /Yb 3+ doped/codoped TZ glass on its optical properties have been investigated. The enhancement in upconversion emission intensity has been explained on the basis of efficient energy transfer and inhomogeneous local field generation around the rare earth ions. The spectroscopic quality factor, absorption and stimulated emission cross-sections, optical gain, quantum efficiency (∼17.53%), energy transfer efficiency (∼61.64%), colour purity (∼94.7%) and ionic nature of the bonding have been determined. The Er 3+ -Yb 3+ -TZWTi glass can be used in visible lasers, yellowish green optical devices and home appliances.

Structural and luminescence studies of Ho{sup 3+}-doped zinc-aluminium-sodium-phosphate (ZANP) glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brahmachary, K.; Rajesh, D.; Ratnakaram, Y. C., E-mail: ratnakaramsvu@gmail.com

Trivalent holmium doped zinc-aluminium-sodium-phosphate (ZANP) glasses were prepared by conventional melt-quenching technique and characterized for their structural and luminescence properties. The amorphous nature, elemental analysis and thermal stability of the glasses were studied by using X-ray diffraction, energy dispersive spectrum and differential scanning calorimetry analysis, respectively. The absorption and fluorescence spectra have been recorded at room temperature. Based on the absorption spectra, the Judd-Ofelt parameters and radiative parameters such as spontaneous transition probabilities (A{sub R}), branching ratios (β{sub R}), radiative lifetimes (τ{sub R}) were calculated and discussed. From the emission spectra emission peak positions (λ{sub P}), effective bandwidths (Δλ{sub eff})more » and stimulated emission cross-sections (σ{sub P}) were calculated for the observed emission transitions,{sup 5}S{sub 2} ({sup 5}F{sub 4}→{sup 5}I{sub 8}) and {sup 5}F{sub 5}→{sup 5}I{sub 8} in all the glass samples. The stimulated emission cross-section is higher for ZANPHo10 glass matrix and so it may be useful for laser excitation.« less

Optical Features of Efficient Europium(III) Complexes with β-Diketonato and Auxiliary Ligands and Mechanistic Investigation of Energy Transfer Process.

PubMed

Bala, Manju; Kumar, Satish; Taxak, V B; Boora, Priti; Khatkar, S P

2016-09-01

Two new europium (III) complexes have been synthesized with 1,3-[bis(4-methoxyphenyl)]propane-1,3-dionato (HBMPD) as main ligand and 2,2'-bipyridyl (bipy) or 1,10-phenanthroline (phen) as an auxiliary ligand. The main ligand HBMPD has been synthesized by ecofriendly microwave approach and complexes by solution precipitation method. The resulting materials are characterized by IR, (1)H-NMR, elemental analysis, X-ray diffraction, UV-visible and TG-DTG techniques. The photoluminescence (PL) spectroscopy depicts the detail analysis of photophysical properties of the complexes, their results show that the ligand interact with Eu (III) ion which act as antenna and transfers the absorbed energy to the central europium(III) ion via sensitization process efficiently. As a consequence of this interaction, these materials exhibit excellent luminescent intensity, long decay time (τ), high quantum efficiency (η) and Judd-Ofelt intensity parameter (Ω2). The CIE coordinates fall under the deep red region, matching well with the NTSC (National Television Standard Committee) standard. Hence, these highly efficient optical materials can be used as a red component in organic light emitting diodes (OLEDs) and full color flat panel displays.

Comparative 4f-4f absorption spectral study for the interactions of Nd(III) with some amino acids: Preliminary thermodynamics and kinetic studies of interaction of Nd(III):glycine with Ca(II)

NASA Astrophysics Data System (ADS)

Moaienla, T.; Bendangsenla, N.; David Singh, Th.; Sumitra, Ch.; Rajmuhon Singh, N.; Indira Devi, M.

2012-02-01

Spectral analysis of Nd(III) complexes with some amino acids viz.; glycine, L-alanine, L-phenylalanine and L-aspartic acid in the presence and absence of Ca 2+ was carried out in some organic solvents; CH 3OH, CH 3CN, DMF and dioxane using comparative absorption spectra of 4f-4f transitions. The study was carried out by evaluating various energy interaction parameters like Slator-Condon ( Fk), Lande factor ( ξ4f), nephelauxetic ratio ( β), bonding parameter ( b1/2), percent-covalency ( δ) by applying partial and multiple regression analysis. The values of oscillator strength ( Pobs) and Judd-Ofelt electric dipole intensity parameter Tλ ( λ = 2, 4, 6) for different 4f-4f transitions have been calculated. On analysis of the variation of the various energy interaction parameters as well as the changes in the oscillator strength ( Pobs) and Tλ values, reveal the mode of binding with the different ligands. Kinetic studies for the complexation of Nd(III):glycine:Ca(II) have also been discussed at different temperatures in DMF medium and from it the values of activation energy ( Ea) and thermodynamic parameters like Δ H°, Δ S° and Δ G° for the complexation are evaluated.

Luminescence properties and molecular mechanics calculation of bis-β-diketonate Eu3+ complex/polymer hybrid fibers

NASA Astrophysics Data System (ADS)

Bai, Jinyuan; Gu, Huiquan; Hou, Yanjun; Wang, Shuhong

2018-05-01

Two series of bis-β-diketonate Eu3+ complex/polymer hybrid fibers, namely, Eu2(BTP)3(H2O)4/PMMA (Eu/PMMA) and Eu2(BTP)3(H2O)4/PVP (Eu/PVP) have been prepared by electrospinning technology (BTP = 1,3-bis(4,4,4-trifluoro-1,3-dioxobutyl)phenyl, PVP = poly (vinyl pyrrolidone) and PMMA = poly (methyl methacrylate)). The effect of complex Eu2(BTP)3(H2O)4 on the luminescence, thermal stability and morphology of composite fibers were studied by characterization techniques. The Judd-Ofelt theory was applied to this study for explaining the effect of the distribution of Eu2(BTP)3(H2O)4 and the mutual effect of the Eu2(BTP)3(H2O)4 coordination compound and neighboring chain segments of PMMA and PVP polymer matrix.

Growth and optical properties of Dy:Y3Al5O12 crystal

NASA Astrophysics Data System (ADS)

Pan, Yuxin; Zhou, Shidong; Li, Dongzhen; Liu, Bin; Song, Qingsong; Liu, Jian; Liu, Peng; Ding, Yuchong; Wang, Xiaodan; Xu, Xiaodong; Xu, Jun

2018-02-01

High optical quality Dy:Y3Al5O12 (Dy:YAG) crystal has been grown by the Czochralski method. Absorption spectra, fluorescence spectra and fluorescence decay curve of Dy:YAG have been recorded at room temperature. The strongest emission of Dy:YAG crystal is near 583 nm, corresponding to the 4F9/2 → 6H13/2 transition. The Judd-Ofelt parameters Ω2, Ω4 and Ω6 were calculated to be 1.49 × 10-20 cm2, 0.94 × 10-20 cm2 and 3.20 × 10-20 cm2, respectively. The radiative transition rates, branching ratios and the emission cross sections were calculated. The fluorescence and radiative lifetimes are 0.40 ms and 1.02 ms, respectively, resulting in a quantum efficiency of 39.2%. The results indicate that the Dy:YAG crystal would be a promising yellow solid state laser material.

Spectral properties of Er3+/Yb3+ codoped tungsten-tellurite glasses.

PubMed

Shen, Xiang; Nie, QiuHua; Xu, TieFeng; Gao, Yuan

2005-07-01

The spectral properties of Er3+/Yb3+ codoped tungsten-tellurite (WT) glasses have been investigated. The measured absorption spectra are analyzed by Judd-Ofelt theory. The compositional change of intensity parameter omega2 is attributed to the change in the covalency between the Er3+ and oxygen ions, the asymmetry in the local structures around the Er3+ ions can be neglected. The lifetimes of 4I(13/2) level of Er3+ in WT glasses are measured and comparable with other TeO2-based glasses. The stimulated emission cross-section is calculated based on McCumber theory. The fluorescence full width at half maximum (FWHM) and the emission cross-section (sigma(peak)) of the 4I(13/2) --> 4I(15/2) transition of Er3+ in different glass hosts have been compared. The suitability of such WT glasses as host materials for 1.5 microm broadband amplification is discussed.

Spectroscopy and visible frequency upconversion in Er3+-Yb3+: TeO2-ZnO glass.

PubMed

Mohanty, Deepak Kumar; Rai, Vineet Kumar

2014-01-01

The UV-Vis-NIR absorption studies of the Er(3+)/Er(3+)-Yb(3+) doped/codoped TeO2-ZnO (TZO) glasses fabricated by the melting and quenching method has been performed. The spectroscopic radiative parameters viz. radiative transition probabilities, branching ratios and lifetimes have been determined from the absorption spectrum by using Judd-Ofelt theory. The near infrared (NIR) to visible frequency upconversion (UC) have been monitored by using an excitation of 976 nm wavelength radiation from a CW diode laser. The effect of codoping with Yb(3+) ions on the intensity of the UC emission bands from the Er(3+) ions throughout visible region has been studied. The mechanism responsible for the observed upconversion emissions in the prepared samples have been explained on the basis of excited state absorption and efficient energy transfer processes. Copyright © 2013 Elsevier B.V. All rights reserved.

Optical transitions of Er3+/Yb3+ codoped TeO2-WO3-Bi2O3 glass.

PubMed

Shen, Xiang; Nie, Qiuhua; Xu, Tiefeng; Gao, Yuan

2005-10-01

Optical absorption and emission properties of the Er3+/Yb3+ codoped TeO2-WO3-Bi2O3 (TWB) glass has been investigated. The transition probabilities, excited state lifetimes, and the branching ratios have been predicted for Er3+ based on the Judd-Ofelt theory. The broad 1.5 microm fluorescence was observed under 970 nm excitation, and its full width at half maximum (FWHM) is 77 nm. The emission cross-section is calculated using the McCumber theory, and the peak emission cross-section is 1.03 x 10(-21) cm2 at 1.531 microm. This value is much larger than those of the silicate and phosphate glasses. Efficient green and weak red upconversion luminescence from Er3+ centers in the glass sample was observed at room temperature, and the upconversion excitation processes have been analyzed.

White light emission of dysprosium doped lanthanum calcium phosphate oxide and oxyfluoride glasses

NASA Astrophysics Data System (ADS)

Luewarasirikul, N.; Kim, H. J.; Meejitpaisan, P.; Kaewkhao, J.

2017-04-01

Lanthanum calcium phosphate oxide and oxyfluoride glasses doped with dysprosium oxide were prepared by melt-quenching technique with chemical composition 20La2O3:10CaO:69P2O5:1Dy2O3 and 20La2O3:10CaF2:69P2O5:1Dy2O3. The physical, optical and luminescence properties of the glass samples were studied to evaluate their potential to using as luminescence materials for solid-state lighting applications. The density, molar volume and refractive index of the glass samples were carried out. The optical and luminescence properties were studied by investigating absorption, excitation, and emission spectra of the glass samples. The absorption spectra were investigated in the UV-Vis-NIR region from 300 to 2000 nm. The excitation spectra observed under 574 nm emission wavelength showed the highest peak centered at 349 nm (6H15/2 → 6P7/2). The emission spectra, excited with 349 nm excitation wavelength showed two major peaks corresponding to 482 nm blue emission (4F9/2 → 6H15/2) and 574 nm yellow emission (4F9/2 → 6H13/2). The experimental lifetime were found to be 0.539 and 0.540 for oxide and oxyfluoride glass sample, respectively. The x,y color coordinates under 349 nm excitation wavelength were (0.38, 0.43) for both glass samples, that be plotted in white region of CIE 1931 chromaticity diagram. The CCT values obtained from the glass samples are 4204 K for oxide glass and 4228 K for oxyfluoride glass corresponding to the commercial cool white light (3100-4500 K). Judd-Ofelt theory had also been employed to obtain the J-O parameters (Ω2, Ω4 and Ω6), oscillator strength, radiative transition possibility, stimulated emission cross section and branching ratio. The Ω2 > Ω4 > Ω6 trend of J-O parameters of both glass samples may indicate the good quality of a glass host for using as optical device application. Temperature dependence of emission spectra was studied from 300 K to 10 K and found that the intensity of the emission peak was found to be increased with decreasing of the temperature. The results of the investigations in this work confirmed that the present Dy-doped lanthanum calcium phosphate oxide and oxyfluoride glasses perform high potential for using as efficient luminescence materials for solid-state lighting applications, especially for white LEDs. Furthermore, the oxyfluoride glass sample provides more luminescence potential than the oxide glass sample.

Fluorescence properties and white light generation from Dy3+-doped niobium phosphate glasses

NASA Astrophysics Data System (ADS)

Srihari, T.; Jayasankar, C. K.

2017-07-01

Niobium phosphate glasses (P2O5+Nb2O5+K2O + Al2O3+Dy2O3) doped with different concentrations of Dy3+ ions have been synthesized by melt quenching technique and characterized through structural and optical measurements to evaluate the fluorescence properties and find their suitability for white light emitting diodes (LEDs). Phonon energy and vibrational groups of the host matrix have been analyzed from Raman spectra. Judd-Ofelt analysis has been applied for 1.0 mol% Dy2O3-doped glass and inturn radiative properties have been evaluated for excited states of the Dy3+ ion. The higher value of stimulated emission cross-section (σe = 6.4 × 10-21 cm2) for the 4F9/2 → 6H13/2 level confirms its potentiality to be used as yellow laser. The decay curves exhibit non-exponential nature at higher concentrations (≥1 mol %) of Dy3+ ion. From the decay curve analysis, the quantum efficiency for the 4F9/2 level of 1.0 mol % Dy3+-doped glass is found to be 92%. The yellow to blue intensity ratios and chromaticity color co-ordinates are found to vary with Dy3+ ion concentrations/excitation wavelengths and are within the white light region.

Blue light emitting Y2O3:Tm3 + nanophosphors with tunable morphology obtained by bio-surfactant assisted sonochemical route

NASA Astrophysics Data System (ADS)

Venkatachalaiah, K. N.; Nagabhushana, H.; Darshan, G. P.; Basavaraj, R. B.; Daruka Prasad, B.; Sharma, S. C.

2017-09-01

Modified sonochemical route was used to prepare Y2O3:Tm3+ (1-11 mol%) nanophosphor using Mimosa pudica (M.P.) leaves extract as bio-surfactant. The prepared samples were exhibited high crystalline nature with various morphologies. This was due to sonochemical experimental reaction took place between cavitation bubbles and nearby solution. The average crystallite sizes of the prepared samples were about 15 nm to 21 nm as obtained from PXRD and TEM analysis. The ultraviolet visible absorption spectra showed prominent bands with an energy gap varied from 5.73 eV to 5.84 eV. Photoluminescence (PL) emission spectra shows the prominent blue light emission peak at 456 nm attributed to 1D2 → 3F4 transitions of Tm3+ ions. Judd-Ofelt intensity parameters were estimated by using PL emission spectra. The photometric characteristics of the prepared compounds were very close to the blue color of NTSC standards. So the results were fruitful in making use of Y2O3:Tm3 + nanophosphor as an alternative material for effective blue component in WLED's.

Luminescence studies on Er3+ -doped zincfluorophosphate glasses for 1.53 μm laser applications

NASA Astrophysics Data System (ADS)

Sreedhar, V. B.; Vijaya, N.; Ramachari, D.; Jayasankar, C. K.

2017-02-01

The Er3+-doped zincfluorophosphate glasses have been prepared by conventional melt-quenching technique and characterized through X-ray diffraction, differential thermal analysis, Raman, visible and near-infrared (NIR) emission spectra and decay time measurements. Judd-Ofelt intensity parameters (Ωλ, λ = 2, 4 and 6) have been derived from the absorption spectrum and inturn used to calculate the radiative properties for the fluorescent levels of Er3+ ions. The studied glasses exhibit intense green and weak red emissions under 378 nm excitation and an intense NIR emission at 1.53 μm under 980 nm laser diode excitation. The wavelength dependence of gain cross-section for different values of population inversion (γ) has been derived from the McCumber theory. Lifetime for the 4I13/2 level of Er3+ ion is found to decrease from 7.17 to 1.42 ms whereas the gain bandwidth increases from 143.5 to 263.9 × 10-28 cm3 with increase of Er3+ concentration from 0.001 to 2.0 mol %. The results indicate that the glasses may be suitable for the development of optical amplifier in the 1.53 μm optical region.

Synthesis and Optical Spectroscopy of YPO4:Eu3+ Orange-Red Phosphors

NASA Astrophysics Data System (ADS)

Yahiaoui, Z.; Hassairi, M. A.; Dammak, M.

2017-08-01

YPO4: x mol.% Eu3+ phosphors with different dopant concentrations ( x = 3, 5, 8, 11, 13) have been synthesized via high-temperature solid-state reaction. X-ray diffraction analysis and Raman and infrared (IR) spectroscopy were applied for detailed structural characterization. Under excitation at wavelength of 395 nm, the photoluminescence spectra displayed the 5D0 → 7F J ( J = 1, 2, 3, 4) intra-4 f shell transitions related to Eu3+ ion. The radiative lifetime was estimated using the Ω 2 and Ω 4 Judd-Ofelt intensity parameters. The highest luminescence intensity was achieved for an optimal europium concentration of 11 mol.%. The critical energy-transfer distance for Eu3+ ions was evaluated to be 10.74 Å. We also studied the temperature-dependent photoluminescence and Commission Internationale de l'Éclairage chromaticity diagram. It was found that Eu3+-doped YPO4 exhibited good thermal stability and its emission intensity decreased slightly above room temperature. In addition, the color purity of this phosphor was as high as 91% for the YPO4:13% Eu3+ sample, making it a potential orange-red phosphor for application in ultraviolet-pumped white light-emitting diodes.

Spectroscopic properties of the 1.4 microm emission of Tm3+ ions in TeO2-WO3-PbO glasses.

PubMed

Balda, R; Lacha, L M; Fernández, J; Arriandiaga, M A; Fernández-Navarro, J M; Muñoz-Martin, D

2008-08-04

In this work, we report the spectroscopic properties of the infrared 3H4-->3F4 emission of Tm3+ ions in two different compositions of glasses based on TeO2, WO3, and PbO for three Tm2O3 concentrations (0.1,0.5, and 1 wt%). Judd-Ofelt intensity parameters have been determined and used to calculate the radiative transition probabilities and radiative lifetimes. The infrared emission at around 1490 nm corresponding to the 3H4-->F4 transition has two noticeable features if compared to fluoride glasses used for S-band amplifiers. On one hand, it is broader by nearly 30 nm, and on the other, the stimulated emission cross section is twice the value for fluoride glasses. Both the relative intensity ratio of the 1490 nm emission to 1820 nm and the measured lifetime of the 3H4 level decrease as concentration increases, due to the existence of energy transfer via cross-relaxation among Tm3+ ions. The analysis of the decays from the 3H4 level with increasing concentration indicates the presence of a dipole-dipole quenching process assisted by energy migration.

Spectroscopic properties of Sm3+ and V4+ ions in Na2O-SiO2-ZrO2 glasses

NASA Astrophysics Data System (ADS)

Neeraja, K.; Rao, T. G. V. M.; Kumar, A. Rupesh; Uma Lakshmi, V.; Veeraiah, N.; Rami Reddy, M.

2013-12-01

Na2O-SiO2-ZrO2 glasses of Sm3+ ions with and without V2O5 are characterized by spectroscopic and optical properties. The XRD and EDS spectra of the glass samples reveal an amorphous nature with different compositions within the glass matrix. The Infrared and Raman spectral studies are carried out and the existence of conventional structural units are analyzed in the glass network. The ESR spectra of the glass samples have indicating that a considerable proportion of vanadium ion exists in V4+ state. The optical absorption spectra of these glasses are recorded at room temperature, from the measured intensities of various absorption bands the Judd-Ofelt parameters Ω2, Ω4 and Ω6 are calculated. The photo-luminescence spectra recorded with excited wavelength 400 nm, five emission bands are observed; in this the energy transfer probability takes place between Sm3+ and V4+ ions.

Fluorescence investigation of Ho3+ in Yb3+ sensitized mixed-alkali bismuth gallate glasses.

PubMed

Lin, H; Zhang, Y Y; Pun, E Y B

2008-12-15

Efficient 2.0 microm infrared and visible upconversion emissions have been observed in Ho3+/Yb3+ co-doped mixed-alkali bismuth gallate (LKBBG) glasses having a maximum-phonon energy of 673 cm(-1). The Judd-Ofelt parameters Omega2, Omega4 and Omega6 of Ho3+ indicate that there is a high asymmetry and strong covalent environment in LKBBG glasses. The large absorption and emission cross-sections of Yb3+ confirm that it is a suitable sensitizer for capturing and transferring pump energy to Ho3+. The emission cross-section profile for the 5I7-->5I8 transition is derived using the reciprocity method and the peak value is 5.54 x 10(-21)cm2, which is much larger than the value in fluorozircoaluminate glasses. LKBBG glasses exhibit low maximum-phonon energy and large refractive index, and it is possible to achieve an effective 1.66 microm U-band emission of Ho3+ under 900 nm laser radiation.

Luminescence of Eu:Y3Al5O12, Eu:Lu3Al5O12, and Eu:GdAlO3 Nanocrystals Synthesized by Solution Combustion

NASA Astrophysics Data System (ADS)

Vilejshikova, E. V.; Khort, A. A.; Podbolotov, K. B.; Loiko, P. A.; Shimanski, V. I.; Shashkov, S. N.; Yumashev, K. V.

2017-11-01

Nanocrystals of rare-earth garnets Y3Al5O12 and Lu3Al5O12 and perovskite GdAlO3 highly doped (10-20 at%) with Eu3+ are synthesized by the solution combustion technique and subsequent annealing in air at 800 and 1300oC. Their structure, morphology, and phase composition are studied. These materials exhibit intense red luminescence under UV excitation. Eu:GdAlO3 luminescence has CIE 1931 color coordinates (0.632, 0.368); dominant wavelength, 599.6 nm; and color purity, >99%. Judd-Ofelt parameters, luminescence branching ratios, and lifetimes of the Eu3+ 5D0 state are determined. The luminescence quantum yield for Eu:GdAlO3 (10 at%) reaches 74% with a lifetime of 1.4 ms for the 5D0 state. The synthesized materials are promising for red ceramic phosphors.

Optical properties of Sm3+ -doped TeO2sbnd WO3sbnd GeO2 glasses for solid state lasers

NASA Astrophysics Data System (ADS)

Subrahmanyam, T.; Gopal, K. Rama; Suvarna, R. Padma; Jamalaiah, B. Chinna; Rao, Ch Srinivasa

2018-03-01

Sm3+ -doped oxyfluoride tellurite-tungsten (TWGSm) glasses were prepared by conventional melt quenching method. The optical properties were investigated through photoluminescence excitation, emission and luminescence decay analysis. The optical band gap energy was determined as ∼3.425 eV for 1.0 mol% of Sm3+ -doped TWGSm glass. Upon 404 nm excitation, the TWGSm glasses emit luminescence through 4G5/2 → 6H5/2 (563 nm), 4G5/2 → 6H7/2 (600 nm), 4G5/2 → 6H9/2 (645 nm) and 4G5/2 → 6H11/2 (705 nm) transitions. The Judd-Ofelt analysis was performed using absorption spectrum and obtained radiative parameters were used to estimate the laser characteristics of present glasses. The concentration of Sm3+ has been optimized as 1.0 mol% for efficient luminescence. The luminescence decay of 4G5/2 emission level was studied by monitoring the emission and excitation wavelengths at 600 and 404 nm, respectively. The experimental lifetime of 4G5/2 level was decrease with increase of Sm3+ concentration. The 1.0 mol% of Sm3+ -doped TWGSm glass could be the best choice for solid state visible lasers to emit orange luminescence.

Spectroscopic properties and energy transfer analysis of Tm3+-doped BaF2-Ga2O3-GeO2-La2O3 glass.

PubMed

Yu, Shenglei; Yang, Zhongmin; Xu, Shanhui

2010-05-01

This paper reports on the spectroscopic properties and energy transfer analysis of Tm(3+)-doped BaF(2)-Ga(2)O(3)-GeO(2)-La(2)O(3) glasses with different Tm(2)O(3) doping concentrations (0.2, 0.5, 2.0, 2.5, 3.0, 3.5, 3.5, 4.0 wt%). Mid-IR fluorescence intensities in the range of 1,300 nm-2,200 nm have been measured when excited under an 808 nm LD for all the samples with the same pump power. Energy level structure and Judd-Ofelt parameters have been calculated based on the absorption spectra of Tm(3+), cross-relaxation rates and multi-phonon relaxation rates have been estimated with different Tm(2)O(3) doping concentrations. The maximum fluorescence intensity at around 1.8 mum has been obtained in Tm(2)O(3)-3 wt% sample and the maximum value of calculated stimulated emission cross-section of Tm(3+) in this sample is about 0.48 x 10(-20) cm(2) at 1,793 nm, and there is not any crystallization peak in the DSC curve of this sample, which indicate the potential utility of Tm(3+)-doped BaF(2)-Ga(2)O(3)-GeO(2)- La(2)O(3) glass for 2.0-microm optical fiber laser.

Ce3+/Yb3+/Er3+ triply doped bismuth borosilicate glass: a potential fiber material for broadband near-infrared fiber amplifiers

PubMed Central

Chu, Yushi; Ren, Jing; Zhang, Jianzhong; Peng, Gangding; Yang, Jun; Wang, Pengfei; Yuan, Libo

2016-01-01

Erbium doped bismuth borosilicate (BBS) glasses, possessing the broadest 1.55 μm near infrared (NIR) emission band among oxide glasses, stand out as excellent fiber material for optical fiber amplifiers. In this work, we demonstrate that both broadened and enhanced NIR emission of Er3+ can be obtained by sensibly combining the effects such as mixed glass former effect, phonon-assisted energy transfer (PAET) and de-excitation effect induced by codopant. Specially, by codoping CeO2 in a controlled manner, it leads to not only much improved optical quality of the glasses, enhanced NIR emission, but also significantly suppressed energy transfer up-conversion (ETU) luminescence which is detrimental to the NIR emission. Cerium incorporated in the glasses exists overwhelmingly as the trivalent oxidation state Ce3+ and its effects on the luminescence properties of Er3+ are discussed. Judd-Ofelt analysis is used to evaluate gain amplification of the glasses. The result indicates that Ce3+/Yb3+/Er3+ triply doped BBS glasses are promising candidate for erbium doped fiber amplifiers. The strategy described here can be readily extended to other rare-earth ions (REs) to improve the performance of REs doped fiber lasers and amplifiers. PMID:27646191

Absorption spectral analysis of 4f-4f transitions for the complexation of Pr(III) and Nd(III) with thiosemicarbazide in absence and presence of Zn(II) in aqueous and organic solvents

NASA Astrophysics Data System (ADS)

Anita, K.; Rajmuhon Singh, N.

2011-10-01

The complexation of thiosemicarbazide with Pr(III) and Nd(III) in absence and presence of Zn(II), a soft metal ion in aqueous and organic solvents like CH 3OH,CH 3CN, dioxane (C 4H 8O 2) and DMF (C 3H 7NO) and their equimolar mixtures are discussed by employing absorption difference and comparative absorption spectrophotometry. Complexation of thiosemicarbazide with Pr(III) and Nd(III) is indicated by the changes in the absorption intensity following the subsequent changes in the oscillator strength of different 4f-4f bands and Judd-Ofelt intensity ( Tλ) parameters. The other spectral parameters like energy interaction parameters namely Slater-Condon ( Fk), Racah ( Ek), Lande ( ξ4f), Nephelauxetic ratio ( β) and bonding parameters ( b1/2) are further computed to explain the nature of complexation. The difference in the energy parameters with respect to donor atoms and solvents reveal that the chemical environment around the lanthanide ions has great impact on f-f transition and any change in the environment result in modification of the spectra. Various solvents and their equimolar mixtures are also used to discuss the participation of solvents in the complexation.

Optical spectroscopy of lanthanide ions in ZnO-TeO2 glasses.

PubMed

Rolli, R; Wachtler, K; Wachtler, M; Bettinelli, M; Speghini, A; Ajò, D

2001-09-01

Zinc tellurite glasses of compositions 19ZnO-80TeO2-1Ln2O3 with Ln = Eu, Er, Nd and Tm were prepared by melt quenching. The absorption spectra were measured and from the experimental oscillator strengths of the f-->f transitions the Judd-Ofelt parameters ohm(lambda) were obtained. The values of the ohm(lambda) parameters are in the range usually observed for oxide glasses. For Nd3+ and Er3+, luminescence spectra in the near infrared were measured and the stimulated emission cross sections sigma(p) were evaluated for some laser transitions. The high values of sigma(p), especially for Nd3+, make them possible candidates for optical applications. Fluorescence line narrowing (FLN) spectra of the Eu3+ doped glass were measured at 20 K, and the energies of the Stark components of the 7F1 and 7F2 states were obtained. A crystal field analysis was carried out assuming a C2v site symmetry. The behaviour of the crystal field ratios B22/B20 and B44/B40 agrees reasonably well with the values calculated using the geometric model proposed by Brecher and Riseberg. The crystal field strength at the Eu3+ sites appears to be very low compared to other oxide glasses.

Investigation of mid-infrared emission characteristics and energy transfer dynamics in Er3+ doped oxyfluoride tellurite glass

PubMed Central

Chen, Fangze; Wei, Tao; Jing, Xufeng; Tian, Ying; Zhang, Junjie; Xu, Shiqing

2015-01-01

Er3+ doped oxyfluoride tellurite glasses have been prepared. Three Judd-Ofelt parameters Ωt (t = 2, 4, 6) and radiative properties are calculated for prepared glasses. Emission characteristics are analyzed and it is found that prepared glasses possess larger calculated predicted spontaneous transition probability (39.97 s−1), emission cross section σem (10.18 × 10−21 cm2) and σem × Δλeff (945.32 × 10−28 cm3), corresponding to the 2.7 μm emission of Er3+: 4I11/2→ 4I13/2 transition. The results suggest that the prepared glasses might be appropriate optical material for mid-infrared laser application. Moreover, rate equation analysis which is rarely used in bulk glass has been carried out to explain the relationship between emission intensity and Er3+ concentration. The calculation results show that with the increment of Er3+ concentration, the energy transfer up-conversion rate of 4I13/2 state increases while the rate of 4I11/2 state reduces, resulting in the change of 2.7 μm emission. PMID:26032900

Role of Er3+ concentration in high-resolution spectra of BaY2 F8 single crystals

NASA Astrophysics Data System (ADS)

Baraldi, A.; Capelletti, R.; Mazzera, M.; Ponzoni, A.; Amoretti, G.; Magnani, N.; Toncelli, A.; Tonelli, M.

2005-08-01

Fourier transform absorption spectroscopy with a resolution as fine as 0.02cm-1 was applied to Er3+ -doped monoclinic BaY2F8 laser crystals in a wide wave number range (500-24000cm-1) and in the temperature range 9-300 K. The careful analysis of the complex narrow line spectra induced by Er3+ allowed us to determine with high accuracy the crystal field splitting of the fundamental I15/24 and of the excited I13/24 , I11/24 , I9/24 , F9/24 , S3/24 , H11/22 , F7/24 , F5/24 , and F3/24 manifolds. On the basis of the experimental data, the crystal-field parameters were determined and Newman’s superposition model was applied: in this way a slight displacement of Er3+ with respect to the Y3+ position was foreseen. The Judd-Ofelt parameters were evaluated: the lifetime values deduced from them were compared to the experimental ones and discussed. The effects caused by increasing Er3+ concentrations (0.5%, 2%, 12%, and 20% atomic fraction) were studied in detail. The new lines, the line broadening, and the line-shape changes were explained in terms of Er3+-Er3+ interaction.

Spectroscopy and excitation dynamics of the trivalent lanthanides Tm(3+) and Ho(3+) in LiYF4

NASA Technical Reports Server (NTRS)

Walsh, Brian M.

1995-01-01

A detailed study of the spectroscopy and excitation dynamics Tm3+ and Ho3+ in yttrium lithium fluoride, LiYF4 (YLF), has been done. Absorption spectroscopy is utilized in the Judd-Ofelt theory to determine radiative transition rates of spontaneous emission. Luminescence spectroscopy is studied under cw diode laser excitation at 785nm. The effect of dopant ion concentration and excitation power on the observed luminescence are considered in these measurements. An analysis of these measurements have been used to determine channels of energy transfer between Tm3+ and Ho3+ ions. The temporal response of Tm and Ho in singly and co-doped YLF to pulsed laser excitation with a Ti:Al2O3 laser and a CoMgF2 laser turned to various wavelengths have also been studied. The energy transfer mechanisms of cross relaxation, upconversion, and resonant energy transfer between Tm3+ and Ho3+ ions have been modeled, and the model parameters extracted by a fitting procedure to the measured temporal response curves. Rate equation approaches to modeling are presented that result in predictions of rate constants for energy transfer processes, as well as more conventional approaches to modeling such as the Forster-Dexter models, which give the interaction strengths in terms of microscopic interaction parameters.

Optical absorption, luminescence, and energy transfer processes studies for Dy3+/Tb3+-codoped borate glasses for solid-state lighting applications

NASA Astrophysics Data System (ADS)

Lakshminarayana, G.; Kaky, Kawa M.; Baki, S. O.; Lira, A.; Caldiño, U.; Kityk, I. V.; Mahdi, M. A.

2017-10-01

By using melt quenching technique, good optical quality singly doped Dy3+ or Tb3+ and Dy3+/Tb3+-codoped borate glasses were synthesized and studied by optical absorption, excitation, emission and decay lifetimes curve analysis. Following the absorption spectrum, the evaluated Judd-Ofelt (J-O) intensity parameters (Ωλ (λ = 2, 4 and 6)) were used to calculate the transition probability (AR), the branching ratio (βR), and the radiative lifetime (τR) for different luminescent transitions such as 4I15/2 → 6H15/2, 4F9/2 → 6H15/2, 4F9/2 → 6H13/2, 4F9/2 → 6H11/2 and 4F9/2 → 6H9/2,6F11/2 for the 0.5 mol % singly Dy3+-doped glass. The βR calculated (65%) indicates that for lasing applications, 4F9/2 → 6H13/2 emission transition is highly suitable. For all the Dy3+/Tb3+-codoped glasses, Tb3+: 5D3→7F6 emission decay lifetime curves are found to be non-exponential in nature for different concentrations of Dy3+ codoping. Using the Inokuti-Hirayama model, these nonexponential decay curves were analyzed to identify the nature of the energy transfer (ET) processes and here the electric dipole-dipole interaction is dominant for the ET. Based on the excitation and emission spectra and decay lifetimes curve analysis, the cross relaxation and ET processes between Dy3+ and Tb3+ were confirmed. For the 0.5 mol % Tb3+ and 2.0 mol % Dy3+-codoped glass, the evaluated Tb3+→Dy3+ ET efficiency (η) is found to be 45% under 369 nm excitation. Further, for Tb3+/Dy3+ -codoped glasses, an enhancement of Tb3+ green emission is observed up to 1.5 mol % Dy3+ codoping, and this is due to the non-radiative resonant ET from Dy3+ to Tb3+ upon 395 nm excitation. For singly 0.5 mol % Dy3+ or 0.5 mol % Tb3+-doped glass, the calculated color coordinates (x,y) and correlated color temperatures (CCT) represent the neutral white or warm white light regions, whereas Dy3+/Tb3+-codoped glasses (x,y) and CCT values fall in the yellowish green region with respect to the different Dy3+ concentrations under 350 and 395 nm excitations. Following the analyzed optical data, the singly Dy3+ or Tb3+-doped and Dy3+/Tb3+-codoped glasses could be suggested as promising materials for their applications in solid state light emitting diodes and luminescent display devices.

Positive influence of Tm3+ on effective Er3+: 3 μm emission in fluoride glass under 980 nm excitation

NASA Astrophysics Data System (ADS)

Huang, Feifei; Wang, Tao; Guo, Yanyan; Lei, Ruoshan; Xu, Shiqing

2017-05-01

Er3+ and Tm3+ singly doped and codoped new fluoride glasses were prepared by traditional melt-quenching method. Efficient 3 μm emission was obtained under 980 nm laser excitation. It is worthy to notice that one of the two ions can be the sensitizer to the other one by depressing the Er3+: 1.5 μm emission through the energy transfer process from Er3+:4I13/2 level to Tm3+:3F4 level. On the basis of measured absorption spectra, the Judd-Ofelt intensity parameters and radiation emission probability were calculated to evaluate the spectroscopic properties. Additionally, the micro-parameters together with the phonon assistance of Er3+:4I13/2 → Tm3+:3F4 and Er3+:4I11/2 → Tm3+:3H5 processes were quantitatively analyzed by using Dexter model. The theoretical micro-parameters results meet well with the experiments which indicates that Er3+/Tm3+ codoped fluoride glass is a potential kind laser glass for 3 μm laser.

Spectroscopic properties of Nd3+ doped transparent oxyfluoride glass ceramics.

PubMed

Yu, Yunlong; Chen, Daqin; Ma, En; Wang, Yuansheng; Hu, Zhongjian

2007-07-01

In this paper, the spectroscopic properties of Nd(3+) doped transparent oxyfluoride glass ceramics containing LaF(3) nano-crystals were systematically studied. The formation and distribution of LaF(3) nano-crystals in the glass matrix were investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Based on Judd-Ofelt theory, the intensity parameters Omega(t) (t=2, 4, 6), spontaneous emission probability, radiative lifetime, radiative quantum efficiency, width of the emission line and stimulated emission cross-section of Nd(3+) were evaluated. Particularly, the effect of Nd(3+) doping level on them was discussed. With the increase of Nd(3+) concentration in the glass ceramic, the experimental luminescence lifetime, radiative quantum efficiency and stimulated emission cross-section vary from 353.4 micros, 78.3% and 1.86 x 10(-20)cm(2) to 214.7 micros, 39.9% and 1.52 x 10(-20)cm(2), respectively. The comparative study of Nd(3+) spectroscopic parameters in different hosts suggests that the investigated glass ceramic system is potentially applicable as laser materials for 1.06 microm emission.

Thermal, Spectral and Laser Properties of Er3+:Yb3+:GdMgB₅O10: A New Crystal for 1.5 μm Lasers.

PubMed

Huang, Yisheng; Yuan, Feifei; Sun, Shijia; Lin, Zhoubin; Zhang, Lizhen

2017-12-25

A novel laser crystal of Er 3+ :Yb 3+ :GdMgB₅O 10 with dimension of 26 × 16 × 12 mm³ was grown successfully from K₂Mo₃O 10 flux by the top seeded solution growth method. The thermal diffusivity and specific heat capacity were measured to calculate the thermal conductivity of the crystal. The absorption and fluorescence properties of the crystal at room temperature were investigated in detail. The Judd-Ofelt method was used to analyze the polarized absorption spectra. The emission cross-section of the ⁴I 13/2 →⁴I 15/2 transition was calculated by the Füchtbauer-Ladenburg formula and the relevant gain cross-sections were estimated. Continuous-wave laser output of 140 mW at 1569 nm with the slope efficiency of 17.8% was demonstrated in a plano-concave resonator. The results reveal that Er 3+ :Yb 3+ :GdMgB₅O 10 crystal is a promising material for 1.5 μm lasers.

Spectroscopic and energy transfer studies of Er3+ ions in B2O3-TeO2-MgO-ZnO glasses

NASA Astrophysics Data System (ADS)

Vijayakumar, M.; Arunkumar, S.; Maheshvaran, K.; Marimuthu, K.

2016-05-01

Composition dependent spectroscopic behavior of Er3+ doped telluroborate glasses were prepared and the energy transfer mechanism in Er3+ ions were investigated for 1.532 µm amplification. The emission cross-section and gain coefficient for 4I13/2→4I15/2 level of Er3+ ions have been analysed through the Judd-Ofelt and McCumber theory. The excited state decay curves were measured and the effect of TeO2 on the lifetime for 4I13/2→4I15/2 level of Er3+ ions has been associated with the various energy transfer mechanism. Further the interaction between Er3+ and OH- were investigated and it was confirmed that the OH free radicals in the prepared glasses are dominant quenching center through the non-radiative relaxation that causes the quenching of 1.532 µm amplification. The non-radiative rate through the OH content were calculated and compared with the reported Er3+ doped glasses.

Enhanced 1.32 μm fluorescence and broadband amplifying for O-band optical amplifier in Nd3+-doped tellurite glass

NASA Astrophysics Data System (ADS)

Zhou, Zi-zhong; Zhou, Ming-han; Su, Xiu-e.; Cheng, Pan; Zhou, Ya-xun

2017-01-01

WO3 oxides with relatively high phonon energy and different concentrations were introduced into the Nd3+-doped tellurite-based glasses of TeO2-ZnO-Na2O to improve the 1.32 μm band fluorescence emission. The absorption spectra, Raman spectra, 1.32 μm band fluorescence spectra and differential scanning calorimeter (DSC) curves were measured, together with the Judd-Ofelt intensity parameters, stimulated emission and gain parameters were calculated to evaluate the effects of WO3 amount on the glass structure and spectroscopic properties of 1.32 μm band fluorescence. It is shown that the introduction of an appropriate amount of WO3 oxide can effectively improve the 1.32 μm band fluorescence intensity through the enhanced multi-phonon relaxation (MPR) processes between the excited levels of Nd3+. The results indicate that the prepared Nd3+-doped tellurite glass with an appropriate amount of WO3 oxide is a potential gain medium applied for the O-band broad and high-gain fiber amplifier.

Nd3+-doped TeO2-PbF2-AlF3 glasses for laser applications

NASA Astrophysics Data System (ADS)

Lalla, E. A.; Rodríguez-Mendoza, U. R.; Lozano-Gorrín, A. D.; Sanz-Arranz, A.; Rull, F.; Lavín, V.

2016-01-01

A study of the optical properties of Nd3+ ion in TeO2-PbF2-AlF3 glasses has been carried out for different Nd3+ concentrations. Based on the Judd-Ofelt theory, intensity parameters and radiative properties were determined from the absorption spectra. Focusing on the suitability of this host for laser applications, the spectroscopic quality factor χ was obtained with a value of 1.07, a value of the order of other compositions proposed as laser hosts. For the most intense emission corresponding with the 4F3/2 → 4I11/2 transition (1.06 μm), the absorption and emission and have been calculated with values of 1.20 × 10-20 cm2, 2.08 × 10-20 cm2. A positive value for the gain cross-sections has been found for a population inversion factor γ of 0.4 in the spectral range from 1060 to 1110 nm. All these results suggest the potentially use of this system as a laser host.

Fluorescence properties of Nd3+-doped tellurite glasses.

PubMed

Kumar, K Upendra; Prathyusha, V A; Babu, P; Jayasankar, C K; Joshi, A S; Speghini, A; Bettinelli, M

2007-07-01

The compositional and concentration dependence of luminescence of the (4)F(3/2)-->(4)I(J) (J=13/2, 11/2 and 9/2) transitions in four Nd(3+)-doped tellurite based glasses has been studied. The free-ion energy levels obtained for 60TeO(2)+39ZnO(2)+1.0Nd(2)O(3) (TZN10) glass have been analysed using the free-ion Hamiltonian model and compared with similar results obtained for Nd(3+):glass systems. The absorption spectrum of TZN10 glass has been analysed using the Judd-Ofelt theory. Relatively longer decay rates have been obtained for Nd(3+)-doped phosphotellurite glasses. The emission characteristics of the (4)F(3/2)-->(4)I(11/2) transition, of the Nd(3+):TZN10 glass, are found to be comparable to those obtained for Nd(3+):phosphate laser glasses. The non-exponential shape of the emission decay curves for the (4)F(3/2)-->(4)I(11/2) transition is attributed to the presence of energy transfer processes between the Nd(3+) ions.

Structural refinement, band-gap analysis and optical properties of GdAlO3 nanophosphors influenced by Dy3+ ion concentrations for white light emitting device applications

NASA Astrophysics Data System (ADS)

Jisha, P. K.; Naik, Ramachandra; Prashantha, S. C.; Nagaswarupa, H. P.; Nagabhushana, H.; Basavaraj, R. B.; Sharma, S. C.; Prasad, Daruka

2016-04-01

Nanosized GdAlO3 phosphors activated with Dy3+ were prepared by a combustion method. Synthesized phosphors were calcined at 1000 °C for 3 h in order to achieve crystallinity. Powder x-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis was used to characterize the prepared product. The orthorhombic phase was observed in the XRD pattern. The particle size of the samples was calculated as around 25 nm. The SEM images show an irregular shape of the prepared nanophosphor. Functional groups of the phosphors were examined by Fourier transform infrared (FTIR) spectroscopy. Photoluminescence (PL) properties of Dy3+ doped GdAlO3 for near-ultraviolet excitation (352 nm) were studied in order to investigate the possibility of its use in white light emitting device applications. Judd-Ofelt intensity parameters, radiative transition rate (A T) and radiative lifetimes (τ rad) were evaluated from the emission spectrum by adopting a standard procedure. The Commission International de l’Eclairage (CIE) color coordinates and correlated color temperature (CCT) are studied for the optimized phosphor. It is found that the color coordinates of Dy3+ doped GdAlO3 powders fall in the white region of the CIE diagram, and the average CCT value was found to be about 6276 K. Therefore, the present phosphor is highly useful for display applications.

Structural, thermal and optical investigations of Dy3+ ions doped lead containing lithium fluoroborate glasses for simulation of white light

NASA Astrophysics Data System (ADS)

Zulfiqar Ali Ahamed, Sd.; Madhukar Reddy, C.; Deva Prasad Raju, B.

2013-05-01

Lead containing barium zinc lithium fluoroborate (LBZLFB) glasses doped with different concentrations of trivalent dysprosium ions were synthesized by conventional melt quenching method and characterized through the XRD, DSC, FTIR, FT-Raman, optical absorption, photoluminescence and decay curve analysis. X-ray diffraction studies revealed amorphous nature of the studied glass matrices. The thermal behavior has been reported by recording DSC thermograms. Coexistence of trigonal BO3 and tetrahedral BO4 units was evidenced by IR and Raman spectroscopy. Judd-Ofelt intensity parameters have been evaluated for 1.0 mol% Dy3+ ions doped LBZLFB glass. The measuring branching ratios are reasonably high for transitions 4F9/2 → 6H15/2 and 6H13/2 suggesting that the emission at 486 and 577 nm, respectively can give rise to lasing action in the visible region. From the visible emission spectra, the yellow to blue (Y/B) intensity ratios and chromaticity color coordinates were estimated. A combination of blue and yellow emissions has emerged in the glasses, which allows the observation of white light when the glasses are excited by the ultraviolet/blue light. These Dy3+ doped glasses are studied for their utility for white light generation under 454 nm excitation and the present LBZLFB glass is more suitable for generation of white light for blue LED chips.

Synthesis of Gd2O3:Eu nanoplatelets for MRI and fluorescence imaging

NASA Astrophysics Data System (ADS)

Maalej, Nabil M.; Qurashi, Ahsanulhaq; Assadi, Achraf Amir; Maalej, Ramzi; Shaikh, Mohammed Nasiruzzaman; Ilyas, Muhammad; Gondal, Mohammad A.

2015-05-01

We synthesized Gd2O3 and Gd2O3 doped by europium (Eu) (2% to 10%) nanoplatelets using the polyol chemical method. The synthesized nanoplatelets were characterized by X-ray diffraction (XRD), FESEM, TEM, and EDX techniques. The optical properties of the synthesized nanoplatelets were investigated by photoluminescence spectroscopy. We also studied the magnetic resonance imaging (MRI) contrast enhancement of T1 relaxivity using 3 T MRI. The XRD for Gd2O3 revealed a cubic crystalline structure. The XRD of Gd2O3:Eu3+ nanoplatelets were highly consistent with Gd2O3 indicating the total incorporation of the Eu3+ ions in the Gd2O3 matrix. The Eu doping of Gd2O3 produced red luminescence around 612 nm corresponding to the radiative transitions from the Eu-excited state 5D0 to the 7F2. The photoluminescence was maximal at 5% Eu doping concentration. The stimulated CIE chromaticity coordinates were also calculated. Judd-Ofelt analysis was used to obtain the radiative properties of the sample from the emission spectra. The MRI contrast enhancement due to Gd2O3 was compared to DOTAREM commercial contrast agent at similar concentration of gadolinium oxide and provided similar contrast enhancement. The incorporation of Eu, however, decreased the MRI contrast due to replacement of gadolinium by Eu.

Synthesis of Gd2O3:Eu nanoplatelets for MRI and fluorescence imaging.

PubMed

Maalej, Nabil M; Qurashi, Ahsanulhaq; Assadi, Achraf Amir; Maalej, Ramzi; Shaikh, Mohammed Nasiruzzaman; Ilyas, Muhammad; Gondal, Mohammad A

2015-01-01

We synthesized Gd2O3 and Gd2O3 doped by europium (Eu) (2% to 10%) nanoplatelets using the polyol chemical method. The synthesized nanoplatelets were characterized by X-ray diffraction (XRD), FESEM, TEM, and EDX techniques. The optical properties of the synthesized nanoplatelets were investigated by photoluminescence spectroscopy. We also studied the magnetic resonance imaging (MRI) contrast enhancement of T1 relaxivity using 3 T MRI. The XRD for Gd2O3 revealed a cubic crystalline structure. The XRD of Gd2O3:Eu(3+) nanoplatelets were highly consistent with Gd2O3 indicating the total incorporation of the Eu(3+) ions in the Gd2O3 matrix. The Eu doping of Gd2O3 produced red luminescence around 612 nm corresponding to the radiative transitions from the Eu-excited state (5)D0 to the (7)F2. The photoluminescence was maximal at 5% Eu doping concentration. The stimulated CIE chromaticity coordinates were also calculated. Judd-Ofelt analysis was used to obtain the radiative properties of the sample from the emission spectra. The MRI contrast enhancement due to Gd2O3 was compared to DOTAREM commercial contrast agent at similar concentration of gadolinium oxide and provided similar contrast enhancement. The incorporation of Eu, however, decreased the MRI contrast due to replacement of gadolinium by Eu.

Spectroscopic behavior of composition dependent Dy3+ doped alkali fluoroborophosphate glasses

NASA Astrophysics Data System (ADS)

Raj, V. Anthony; Maheshvaran, K.; D'Silva, A. Josuva; Rayappan, I. Arul

2018-04-01

A new series of Dy3+ doped Alkali fluoroborophosphate glasses were prepared following conventional melt quenching technique and characterized using optical absorption and luminescence measurements. The nature of the metal-ligand bonding and the electronic band structure has been investigated using the absorption spectra. The Judd-Oflet (JO) intensity parameters (Ω2, Ω4 and Ω6) were evaluated and the experimental oscillator strength values were also calculated. The luminescence spectra exhibit two visible bands 4F9/2→6H15/2 (Blue) and 4F9/2→6H13/2 (Yellow) respectively. The radiative properties such as peak wavelength and effective band width for the emission transition were calculated. The yellow to blue (Y/B) ratios and color coordinates have been calculated from the luminescence spectra and the utility of the present glasses for white LED applications.

Optical studies on alkali-alkaline Dy3+-doped lead-alumino-boro-phosphate glasses for white LED's application

NASA Astrophysics Data System (ADS)

Joseph, P. Arun Jeganatha; Vinothini, J. Jemma; Maheshvaran, K.; Rayappan, I. Arul

2018-04-01

A new series 34B2O3+20NH4H2PO4+10Al2O3+10PbO+25MCO3+1Dy2O3, where (M= K2 and Mg) of Dy3+ doped lead-alumino-boro-phosphate glasses have been prepared by conventional melt quenching technique. The prepared glass samples were characterized through Optical absorption and photoluminescence spectra. The bonding parameter, Oscillator strength and Judd-Oflet (JO) parameter have been calculated and investigated through optical absorption spectra. The excitation and emission wavelength have been obtained through the photoluminescence spectra. The emission spectra exhibit two visible bands as 4F9/2→6H15/2 (Blue) and 4F9/2→6H13/2 (Yellow). Yellow to blue (Y/B) intensity ratio and chromaticity coordinates have been estimated for the stimulation of WLED applications.

Judd's Debt to Wundt

ERIC Educational Resources Information Center

Dunkel, Harold B.

1977-01-01

Charles Judd identified closely with Wilhelm Wundt's philosophy and general psychological position. This article traces Judd's views on the American educational system in the early part of this century, some of the persistent themes that were part of Judd's thought, and Wundt's influence on Judd's thinking. Also discusses Judd's efforts to collect…

Spectroscopic and energy transfer studies of Er{sup 3+} ions in B{sub 2}O{sub 3}–TeO{sub 2}–MgO–ZnO glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vijayakumar, M.; Arunkumar, S.; Marimuthu, K., E-mail: mari-ram2000@yahoo.com

2016-05-23

Composition dependent spectroscopic behavior of Er{sup 3+} doped telluroborate glasses were prepared and the energy transfer mechanism in Er{sup 3+} ions were investigated for 1.532 µm amplification. The emission cross-section and gain coefficient for {sup 4}I{sub 13/2}→{sup 4}I{sub 15/2} level of Er{sup 3+} ions have been analysed through the Judd-Ofelt and McCumber theory. The excited state decay curves were measured and the effect of TeO{sub 2} on the lifetime for {sup 4}I{sub 13/2}→{sup 4}I{sub 15/2} level of Er{sup 3+} ions has been associated with the various energy transfer mechanism. Further the interaction between Er{sup 3+} and OH{sup −} were investigatedmore » and it was confirmed that the OH free radicals in the prepared glasses are dominant quenching center through the non-radiative relaxation that causes the quenching of 1.532 µm amplification. The non-radiative rate through the OH content were calculated and compared with the reported Er{sup 3+} doped glasses.« less

UV- Vis- NIR and luminescent characterization of PZCdO:Tm laser oxide glasses

NASA Astrophysics Data System (ADS)

Al-Assiri, M. S.; Algarni, H.; Reben, M.; Yousef, E.; Hegazy, H. H.; AbouDeif, Y. M.; Umar, Ahmad

2017-11-01

The luminescent oxide glasses with composition 50P2O5- 30ZnO- 20CdO (PZCdO pure) and 50P2O5- 30ZnO- 20CdO- 30000 ppm Tm2O3 (PZCdO:Tm) were synthesized by using melt- quenching technique. The optical energy gap and Urbach energy of these glasses were calculated by using UV-Vis-NIR spectroscopy. Judd- Ofelt parameters Ω2, Ω4 and Ω6, branching ratio, βR, and radiative lifetimes, τR, of Tm3+ ions doped PZCdO glasses were estimated. The spectroscopic results showed that the present glasses has the effective emission cross section bandwidth (Δλeff = 90 nm) and high stimulated emission cross-section (σem = 1.5 × 10-21 cm2). The blue up conversion emissions sharp band at 458 nm corresponding to transition 1D2 → 3F6 and weak emission band in NIR region assigned to 1G4→3H4 for the glasses PZCdO:Tm with UV- excited at 354 nm region were obtained. From result we can suggest that the present glasses can be used for blue light emitting diodes BLED chip.

Luminescence properties of Eu3+ doped CdF2 single crystals

NASA Astrophysics Data System (ADS)

Boubekri, H.; Diaf, M.; Guerbous, L.; Jouart, J. P.

2018-04-01

This paper reports the photoluminescence properties of Eu3+ doped CdF2 single crystals. The pulled crystals were prepared by use of the Bridgman technique from a vacuum furnace in fluoride atmosphere. Absorption, excitation and emission spectra of the crystal doped with three Eu3+ concentrations (0.02%, 0.1% and 0.6% mol.) were recorded at room temperature. The emission spectra exhibit a strong yellow and red emissions in the spectral range 550-720 nm which are assigned to 5D0 → 7FJ (J = 1, 2, 4) transitions and a weak infrared emission around 816 nm corresponding to 5D0 → 7F6 transition. The magnetic dipole emission (5D0 → 7F1) is the most intense for each Eu3+ concentration. The Judd-Ofelt intensity parameters Ω2, Ω4, Ω6 for 4f-4f transitions of Eu3+ ions were computed from the emission spectra using the 5D0 → 7FJ (J = 1, 2, 4, 6) transitions. Via these phenomenological intensity parameters, the spontaneous emission probabilities, branching ratios, radiative lifetimes, quantum efficiencies and emission cross-sections for the main Eu3+ emitting levels are evaluated.

Energy transfer characteristics of silicate glass doped with Er3+, Tm3+, and Ho3+ for ˜2 μm emission

NASA Astrophysics Data System (ADS)

Li, Ming; Liu, Xueqiang; Guo, Yanyan; Hu, Lili; Zhang, Junjie

2013-12-01

A Er3+/Tm3+/Ho3+ tri-doped silicate glass with good thermal stability is prepared by melt-quenching method. Efficient ˜2 μm emission is observed under 808 nm laser excitation. It is found that the 2.0 μm emission of Ho3+ can be enhanced under the excitation at 808 nm by incorporating Er3+ and Tm3+. Based on the measurement of absorption spectra, the Judd-Ofelt intensity parameters, radiation emission probability, and branching ratio are calculated to evaluate the spectroscopic properties simultaneously. The maximum value of emission cross section of Ho3+ is 3.54 × 10-21 cm2 at 2008 nm. Additionally, the phonon assistance and the micro-parameters in the energy transfer process are quantitatively analyzed by using Dexter model. The energy transfer coefficient from Tm3+ to Ho3+ can reach as high as 21.44 × 10-40 cm6/s, respectively. The emission property together with good thermal property indicates that Er3+/Tm3+/Ho3+ tri-doped silicate glass is a potential kind of laser glass for efficient 2 μm laser.

Intense green emission from Tb3+- doped Teo2-Wo3-Geo2 glasses

NASA Astrophysics Data System (ADS)

Subrahmanyam, Tallam; Gopal, Kotalo Rama; Suvarna, Reniguntla Padma; Jamalaiah, Bungala Chinna

2018-04-01

Tb3+ -doped oxyfluoro tellurite (TWGTb) glasses were prepared by conventional melt quenching technique. The Judd-Ofelt theory has been applied to evaluate the Ωλ (λ=2,4,6) intensity parameters. The TWGTb glasses exhibit 5D3 → 7F5-3 and 5D4 → 7F6-0 transitions when excited at 316 nm wavelength. The variation of intensity of 5D4 → 7F5 (Green) and 5D3 → 7F4 (Blue) transitions and the green to blue (IG/IB) intensity ratios were studied as a function of Tb3+ ions concentration. The laser characteristic parameters such as effective bandwidth (Δλeff), stimulated emission cross-section (σe), gain bandwidth (σe×Δλeff) and optical gain (σe×τR) were determined using the emission spectra and radiative parameters. The luminescence decay profiles exhibit single-exponential nature for all the samples. Based on the experimental results we suggest that the 1.0 mol% of Tb3+-doped TWGTb glass could be the suitable laser host materials to emit intense green luminescence at 545 nm.

Europium(III)-doped A2Hf2O7 (A = Y, Gd, Lu) nanoparticles: Influence of annealing temperature, europium(III) concentration and host cation on the luminescent properties

NASA Astrophysics Data System (ADS)

Papan, Jelena; Jovanović, Dragana J.; Vuković, Katarina; Smits, Krisjanis; Đorđević, Vesna; Dramićanin, Miroslav

2016-11-01

The detailed analyses of structure and luminescence of europium(III)-doped A2Hf2O7 (A = Y, Gd, Lu) nanoparticles is presented. Samples were prepared by time and cost effective combustion method that utilize polyethylene glycol both as a chelating agent and as a fuel, with different europium(III) concentrations (from 1 to 12 at.%), annealed at temperatures ranging from 800 to 1400 °C, and with alternating A3+ cation in the A2Hf2O7 host. Then, structural variations between materials were analysed by X-ray diffraction and structural refinement, while the changes in the luminescence were assessed from the Judd-Ofelt analyses of emission spectra. Nanoparticles prepared at the lowest temperature (800 °C) had the smallest particle size of ∼6 nm and showed the highest quantum efficiency when doped with 1 and 2 at.% of europium(III). Radiative transition rate and quantum efficiency of emission showed Lu2Hf2O7 > Gd2Hf2O7 > Y2Hf2O7 trend.

Spectroscopy of Tb3+ ions in monoclinic KLu(WO4)2 crystal application of an intermediate configuration interaction theory

NASA Astrophysics Data System (ADS)

Loiko, Pavel; Volokitina, Anna; Mateos, Xavier; Dunina, Elena; Kornienko, Alexey; Vilejshikova, Elena; Aguiló, Magdalena; Díaz, Francesc

2018-04-01

The spectroscopic properties of Tb3+ ions in monoclinic KLu(WO4)2 double tungstate crystal are studied with polarized light. The absorption spectra in the visible, near- and mid-IR including the transitions to all lower-lying 7FJ (J = 0 … 5) excited states are measured. The maximum absorption cross-section for the 7F6 → 5D4 transition is 3.42 × 10-21 cm2 at 486.7 nm for light polarization E || Nm. The transition probabilities for Tb3+ ions are calculated within the Judd-Ofelt theory modified for the case of an intermediate configuration interaction (ICI). The radiative lifetime of the 5D4 state is 450 μs and the luminescence quantum yield is >90%. The polarized stimulated-emission cross-section spectra for all 5D4 → 7FJ (J = 0 … 6) emission channels are evaluated. The maximum σSE is 11.4 × 10-21 cm2 at 549.4 nm (for E || Nm). Tb3+:KLu(WO4)2 features high transition cross-sections for polarized light being promising for color-tunable visible lasers and imaging.

Effect of PbO on the spectral and thermo-optical properties of Nd3+-doped phosphate laser glass

NASA Astrophysics Data System (ADS)

Yin, Qianwen; Kang, Shuai; Wang, Xue; Li, Shunguang; He, Dongbing; Hu, Lili

2017-04-01

Nd3+-doped P2O5-K2O-Al2O3-BaO-PbO phosphate glasses with various PbO/BaO ratios were synthesized using the melt quenching technique. Raman, absorption, and emission spectra were measured to investigate the effects of PbO/BaO ratios on the structures and spectroscopic properties of the glasses. The emission cross-sections of the Nd3+-doped phosphate glasses were calculated using the Judd-Ofelt theory, and were found to increase from 4.37 × 10-20 to 4.50 × 10-20 cm2 as the PbO/BaO ratio increased. In addition, thermo-optical properties were measured using an interferometric technique. The thermo-optical coefficients, which were -1.49 × 10-6, -1.65 × 10-6, and -1.64 × 10-6 K-1, respectively, were all largely negative values. The thermal expansion coefficients of the three glass samples varied within a small range. The results showed that increasing the PbO/BaO ratio of phosphate glasses can improve the laser properties while maintaining their good thermo-optical properties.

Effect of Bi2O3 on spectroscopic and structural properties of Er3+ doped cadmium bismuth borate glasses.

PubMed

Sanghi, S; Pal, I; Agarwal, A; Aggarwal, M P

2011-12-01

Glasses with composition 20CdO·xBi(2)O(3)·(79.5-x)B(2)O(3) (15≤x≤35, x in mol%) containing 0.5 mol% of Er(3+) ions were prepared by melt-quench technique (1150°C in air). The amorphous nature of the glasses was confirmed by X-ray diffraction. The spectroscopic properties of the glasses were investigated using optical absorption spectra and fluorescence spectra. The phenomenological Judd-Ofelt intensity parameters Ω(λ) (λ=2, 4, 6) were determined from the spectral intensities of absorption bands in order to calculate the radiative transition probability (A(R)), radiative life time (τ(R)), branching ratios (β(R)) for various excited luminescent states. Using the near infrared emission spectra, full width at half maxima (FWHM), stimulated emission cross-section (σ(e)) and figure of merit (FOM) were evaluated and compared with other hosts. Especially, the numerical values of these parameters indicate that the emission transition (4)I(13/2)→(4)I(15/2) at 1.506 μm in Er(3+)-doped cadmium bismuth borate glasses may be useful in optical communication. Copyright © 2011 Elsevier B.V. All rights reserved.

Thermal properties and optical transition probabilities of Tm3 + doped TeO2-WO3 glass.

PubMed

Cenk, S; Demirata, B; Oveçoglu, M L; Ozen, G

2001-10-01

Glasses with the composition of (1 - x)TeO2 + (x)WO3, where x = 0.15, 0.25 and 0.3 were prepared and, their thermal and absorption measurements were carried out. Differential thermal analysis (DTA) curves taken in the 23-600 degrees C temperature range with a heating rate of 10 degrees C/min reveal a change in the value of the glass transition temperature, Tg, while crystallization was not observed for the glasses containing a WO3 content of more than 15 mol%. All the glasses were found to be moisture-resistant. The absorption bands corresponding to the absorption of the 1G4, 3F2, 3F3 and 3F4, 3H5 and 3H4 levels from the 3H6 ground level of the Tm3+ ion were observed in the optical absorption spectra. Integrated absorption cross-sections of each band except that of 3H5 level was found to vary with the glass composition. Judd-Ofelt analysis was carried out for the samples doped with 1.0 mol% Tm2O3. The omega2 parameter shows the strongest dependence on the host composition and it increases with the increasing WO3 amount. The value of omega4 increases rather slowly while the value of omega6 is practically independent of the composition. The strong dependence of the parameter omega2 indicates that this parameter is related to the structural change and the symmetry of the local environment of the Tm3+ ions in this glass.

Optical spectroscopy of Sm(3+) doped Na2O-ZnO-La2O3-TeO2 glasses.

PubMed

Sobczyk, Marcin

2015-10-05

Telluride glasses with the composition xSm2O3-(7-x)La2O3-3Na2O-25ZnO-65TeO2 (where x=0.1, 1, 2, 5 and 7 mol%) were obtained by the melt quenching technique. Electronic absorption and fluorescence spectra as well as fluorescence dynamics of the Sm(3+)-doped title glasses are presented and analysed in detail. A Judd-Ofelt intensity analysis of the absorption spectrum at 300 K has been applied for determination of Ωλ parameters (Ω2=3.10, Ω4=3.80, Ω6=1.61×10(-20) cm(2)) which in turn have been used for calculations of the radiative transition probabilities (AT), the natural (radiative) lifetimes (τR) of the (4)G5/2 level of Sm(3+), the fluorescence branching ratios (β) and the emission cross-sections (σem). The τR value of the (4)G5/2 level amount to 1546 μs and is slightly higher than the measured decay time of 1306 μs. With the increasing of Sm2O3 concentration from 0.1 to 7.0 mol% the experimental lifetime of the fluorescent level decreases from 1306 to 41 μs. An analysis of the non-radiative decay was based on the cross-relaxation mechanisms. The optical achieved results indicate that the investigated glasses are potentially applicable as an orange and/or red laser host. Copyright © 2015 Elsevier B.V. All rights reserved.

Optical spectroscopy and luminescence properties of Ho3+ doped zinc fluorophosphate (ZFP) glasses for green luminescent device applications

NASA Astrophysics Data System (ADS)

Reddy Prasad, V.; Damodaraiah, S.; Ratnakaram, Y. C.

2018-04-01

Ho3+ doped zinc fluorophosphate (ZFP) glasses with molar chemical compositions, (60-x) NH4H2PO4+20ZnO+10BaF2+10NaF+xHo2O3 (where x = 0.1, 0.3, 0.5, 1.0 and 1.5 mol%) were prepared by melt quenching technique. These glasses were characterized through physical, structural, optical, excitation, luminescence and decay curve analysis. From the absorption spectra, spectral intensities (fexp and fcal), Judd-Ofelt intensity parameters (Ω2, Ω4 and Ω6), radiative transition probabilities (AT), radiative lifetimes (τR) and branching ratios (βR) were evaluated for all Ho3+ doped ZFP glass matrices. From the photoluminescence spectra, peak stimulated emission cross-sections (σP) were calculated for all Ho3+ doped ZFP glasses. The Ho3+ doped ZFP glasses show strong green emission at 545 nm and red emission at 656 nm under excitation, 450 nm. The measured lifetimes (τmeas) of (5S2)5F4 level of Ho3+ doped ZFP glasses were obtained from decay profiles. The CIE color coordinates of Ho3+ doped ZFP glasses were calculated from emission spectra and 1.0 mol% of Ho3+ doped ZFP glass matrix gives green emission. Hence, these results confirm that the Ho3+ doped ZFP glasses could be considered as a promising candidate for visible green laser applications.

Antimony oxide based glasses, novel laser materials

NASA Astrophysics Data System (ADS)

Ouannes, Karima; Lebbou, Kheirreddine; Walsh, Brian M.; Poulain, Marcel; Alombert-Goget, Guillaume; Guyot, Yannick

2017-03-01

Glasses based on Sb2O3 make one of the major classes of heavy metal oxide glasses. This paper concerns two antimonite glasses, 88Sb2O3-10Na2O-2Bi2O3 (SNB2) and 60Sb2O3-20WO3-19Na2O-1Bi2O3 (SWNB1), doped with 0.25 mol% Er2O3. Bulk samples have been prepared and their absorption and fluorescence spectra have been recorded. Differential scanning calorimeter (DSC) measurements emphasize a thermal stability range ΔT > 100 °C that expresses a good stability against devitrification. Both FTIR and Raman spectra provide information on the structural organization of the glasses. The maximum phonon energies are 700 cm-1 and 920 cm-1 for SNB2 and SWNB1 glasses, respectively. The spectroscopic analysis of the absorption and emission properties of the Er3+ ions in the SNB2 and SWNB1 glasses has been performed. The Judd-Ofelt theory has been applied to interpret the local environment of the Er3+ ion site and covalency of the Ersbnd O bond, but also to determine the radiative lifetime (τr) for 4I13/2 → 4I15/2 emission transition. The emission cross-sections for the 4I13/2 → 4I15/2 transition (1528 nm) were calculated using McCumber and Füchtbauer-Ladenburg theories. We discuss the potential application of these glasses.

Optical characterization of Tm(3+) doped Bi2O3-GeO2-Ga2O3 glasses in absence and presence of BaF2.

PubMed

Han, Kexuan; Zhang, Peng; Wang, Shunbin; Guo, Yanyan; Zhou, Dechun; Yu, Fengxia

2016-08-10

In this paper, Two new Bi2O3-GeO2-Ga2O3 glasses (one presence of BaF2) doped with 1mol% Tm2O3 were prepared by melt-quenching technique. Differential thermal analysis (DTA), the absorption, Raman, IR spectra and fluorescence spectra were measured. The Judd-Ofelt intensity parameters, emission cross section, absorption cross section, and gain coefficient of Tm(3+) ions were comparatively investigated. After the BaF2 introduced, the glass showed a better thermal stability, lower phonon energy and weaker OH(-) absorption coefficient, meanwhile, a larger ~1.8 μm emission cross section σem (7.56 × 10(-21) cm(2)) and a longer fluorescence lifetime τmea (2.25 ms) corresponding to the Tm(3+): (4)F3 → (3)H6 transition were obtained, which is due to the addition of fluoride in glass could reduce the quenching rate of hydroxyls and raise the cross-relaxation ((3)H6 + (3)H4 → (3)F4 + (3)F4) rate. Our results suggest that the Tm(3+) doped Bi2O3-GeO2-Ga2O3 glass with BaF2 might be potential to the application in efficient ~1.8 μm lasers system.

Structural and photoluminescence properties of stannate based displaced pyrochlore-type red phosphors: Ca(3-x)Sn₃Nb₂O₁₄:xEu³⁺.

PubMed

Sreena, T S; Prabhakar Rao, P; Francis, T Linda; Raj, Athira K V; Babu, Parvathi S

2015-05-14

New stannate based displaced pyrochlore-type red phosphors, Ca(3-x)Sn3Nb2O14:xEu(3+), were prepared via a conventional solid state method. The influence of partial occupancy of Sn in both A and B sites of the pyrochlore-type oxides on the photoluminescence properties was studied using powder X-ray diffraction, FT-Raman, transmission electron microscopy, scanning electron microscopy with energy dispersive spectrometry, UV-visible absorption spectroscopy, and photoluminescence excitation and emission spectra with lifetime measurements. The structural analysis establishes that these oxides belong to a cubic displaced pyrochlore type structure with a space group Fd3̄m. These phosphors exhibit strong absorptions at near UV and blue wavelength regions and emit intense multiband emissions due to Eu(3+ 5)D0-(7)F(0, 1, 2) transitions. The absence of characteristic MD transition splitting points out that local cation disorder exists in this type of displaced pyrochlores, reducing the D(3d) inversion symmetry, which is not evidenced by such disorder in the X-ray diffraction analysis. The unusual forbidden intense sharp (5)D0-(7)F0 transition indicates single site occupancy of Eu(3+) with a narrower range of bonding environment, preventing the cluster formation. This is supported by the stable (5)D0 lifetime with Eu(3+) concentration. The Judd-Ofelt intensity parameter assessment corroborates these results. The CIE color coordinates of these phosphors were found to be (0.60, 0.40), which are close to the NTSC standard values (0.67, 0.33) for a potential red phosphor.

An absorption spectral study of Nd (III) with glutathione (reduced), GSH in aqueous and aquated organic solvent in presence and absence of Zn (II)

NASA Astrophysics Data System (ADS)

Mehta, Jignasu P.; Bhatt, Prashant N.; Misra, Sudhindra N.

2003-02-01

The coordination chemistry of glutathione (reduced) GSH is of great importance as it acts as an excellent model system for the binding of metal ions. The GSH complexation with metal ions is involved in the toxicology of different metal ions. Its coordination behaviour for soft metal ions and hard metal ions is found different because of the structure of GSH and its different potential binding sites. We have studied two chemically dissimilar metal ions viz. Nd (III) being hard metal ion, which will prefer hard donor sites like carboxylic groups, and Zn (II) the soft metal ion more suited to peptide-NH and sulfhydryl groups. The absorption difference and comparative absorption spectroscopy involving 4f-4f transitions of the heterobimetallic complexation of GSH with Nd (III) and Zn (II) has been explored in aqueous and aquated organic solvents. The changes in the oscillator strengths of different 4f-4f bands and Judd-Ofelt intensity (Tλ) parameters determined experimentally is being used to investigate the complexation of GSH. The in vivo intracellular complexation of GSH with Ca (II) in presence of Zn (II) ion has been mimicked through Nd (III)-GSH-Zn (II) absorption spectral studies in vitro.

2.7 μm emission properties of Er3+ doped tungsten-tellurite glass sensitized by Yb3+ ions.

PubMed

Guo, Yanyan; Ma, Yaoyao; Huang, Feifei; Peng, Yapei; Zhang, Liyan; Zhang, Junjie

2013-07-01

With a 980 nm laser diode (LD) pumped, the sensitized effect of Yb(3+) ions on 2.7 μm emission properties and energy transfer mechanism in Yb(3+)/Er(3+) co-doped tungsten-tellurite glass were investigated in present paper. Based on absorption spectra, Judd-Ofelt parameters and radiative transition probabilities were calculated and analyzed. The emission spectra were tested and the optimized concentration ratio of Yb(3+) to Er(3+) ions was found to be 3:0.5 with a largest calculated emission cross-section (6.05×10(-21) cm(2)) corresponding to Er(3+):(4)I11/2→(4)I13/2 transition. When the concentration ratio of Yb(3+) to Er(3+) ions was 4:0.5, 1.5 μm and 2.7 μm emission decreased while up-conversion increased. The decreased 1.5 μm and 2.7 μm emission were induced by the saturation of Er(3+):(4)I13/2 level. In brief, the advantageous spectroscopic characteristics indicated that Yb(3+)/Er(3+) co-doped tungsten-tellurite glass may be a promising candidate for application of 2.7 μm emission. Copyright © 2013 Elsevier B.V. All rights reserved.

Optical properties of Nd3+ doped bismuth zinc borate glasses

NASA Astrophysics Data System (ADS)

Shanmugavelu, B.; Venkatramu, V.; Ravi Kanth Kumar, V. V.

2014-03-01

Glasses with compositions of (100-x) (Bi2ZnOB2O6) - x Nd2O3 (where x = 0.1, 0.3, 0.5, 1 and 2 mol%) were prepared by melt quenching method and characterized through optical absorption, emission and decay curve measurements. Optical absorption spectra have been analyzed using Judd-Ofelt theory. The emission spectra exhibit three peaks at 919, 1063 and 1337 nm corresponding to 4F3/2 to 4I9/2, 4I11/2 and 4I13/2 transitions in the near infrared region. The emission intensity of the 4F3/2 to 4I11/2 transition increases with increase of Nd3+ concentration up to 1 mol% and then concentration quenching is observed for 2 mol% of Nd3+ concentration. The lifetimes for the 4F3/2 level are found to decrease with increase in Nd2O3 concentration in the glasses. The decay curves of the glass up to 0.3 mol% of Nd3+ exhibit single exponential nature and thereafter the curves become nonexponential nature (0.5, 1 and 2 mol%). The nonexponential curve has been fitted to the Inokuti-Hirayama model to understand the nature of energy transfer process.

Novel EGCG assisted ultrasound synthesis of self-assembled Ca2SiO4:Eu(3+) hierarchical superstructures: Photometric characteristics and LED applications.

PubMed

Venkataravanappa, M; Nagabhushana, H; Darshan, G P; Daruka Prasad, B; Vijayakumar, G R; Premkumar, H B; Udayabhanu

2016-11-01

This paper reports for the first time ultrasound, EGCG assisted synthesis of pure and Eu(3+) (1-5mol%) activated Ca2SiO4 nanophosphors having self-assembled superstructures with high purity. The shape, size and morphology of the product were tuned by controlling influential parameters. It was found that morphology was highly dependent on EGCG concentration, sonication time, pH and sonication power. The probable formation mechanism for various hierarchical superstructures was proposed. The PL studies of Ca2SiO4:Eu(3+) phosphors can be effectively excited by the near ultraviolet (UV) (396nm) light and exhibited strong red emission around 613nm, which was attributed to the Eu(3+) ((5)D0→(7)F2) transition. The concentration quenching phenomenon was explained based on energy transfer between defect and Eu(3+) ions, electron-phonon coupling and Eu(3+)-Eu(3+) interaction. The Judd-Ofelt intensity parameters and radiative properties were estimated by using PL emission spectra. The photometric studies indicate that the obtained phosphors could be a promising red component for possible applications in the field of white light emitting diodes. Copyright © 2016 Elsevier B.V. All rights reserved.

Local symmetric distortion boosted photon up-conversion and thermometric sensitivity in lanthanum oxide nanospheres.

PubMed

Suo, Hao; Zhao, Xiaoqi; Zhang, Zhiyu; Shi, Rui; Wu, Yanfang; Xiang, Jinmeng; Guo, Chongfeng

2018-05-17

It is essential to simultaneously boost the luminescence intensity and thermometric sensitivity of up-converted optical thermometers towards potential biomedical sensing applications. Herein, the effects of local site symmetry on the up-conversion (UC) emission and thermal sensing ability in trigonal-phased La2O3:Er3+/Yb3+ nanospheres were qualitatively explored using cubic-phased Lu2O3 and Y2O3 with a similar shape and phonon energy as contrasts. Under 980 nm light excitation, much stronger UC emissions were detected in La2O3 samples than that in cubic Lu2O3 and Y2O3 samples, and the possible mechanisms were elaborately proposed using Eu3+ as a luminescent probe. Thermo-responsive emission intensity from 2H11/2/4S3/2 levels was monitored to evaluate the absolute sensitivity of three samples, which strongly depends on the dopant-induced local site symmetric distortions according to the Judd-Ofelt theory. The potentiality of La2O3:Er3+/Yb3+ for sub-tissue thermometry was also validated by ex vivo experiments. Results open a promising avenue for realizing highly sensitive thermometry with a large signal-to-noise ratio in sub-tissues via finely tailoring the local site symmetry.

Spectroscopic investigation of zinc tellurite glasses doped with Yb(3+) and Er(3+) ions.

PubMed

Bilir, Gökhan; Kaya, Ayfer; Cinkaya, Hatun; Eryürek, Gönül

2016-08-05

This paper presents a detailed spectroscopic investigation of zinc tellurite glasses with the compositions (0.80-x-y) TeO2+(0.20) ZnO+xEr2O3+yYb2O3 (x=0, y=0; x=0.004, y=0; x=0, y=0.05 and x=0.004, y=0.05 per moles). The samples were synthesized by the conventional melt quenching method. The optical absorption and emission measurements were conducted at room temperature to determine the spectral properties of lanthanides doped zinc tellurite glasses and, to study the energy transfer processes between dopant lanthanide ions. The band gap energies for both direct and indirect possible transitions and the Urbach energies were measured from the absorption spectra. The absorption spectra of the samples were analyzed by using the Judd-Ofelt approach. The effect of the ytterbium ions on the emission properties of erbium ions was investigated and the energy transfer processes between dopant ions were studied by measuring the up-conversion emission properties of the materials. The color quality parameters of obtained visible up-conversion emission were also determined as well as possibility of using the Er(3+) glasses as erbium doped fiber amplifiers at 1.55μm in infrared emission region. Copyright © 2016 Elsevier B.V. All rights reserved.

Spectroscopic investigation of zinc tellurite glasses doped with Yb3 + and Er3 + ions

NASA Astrophysics Data System (ADS)

Bilir, Gökhan; Kaya, Ayfer; Cinkaya, Hatun; Eryürek, Gönül

2016-08-01

This paper presents a detailed spectroscopic investigation of zinc tellurite glasses with the compositions (0.80 - x - y) TeO2 + (0.20) ZnO + xEr2O3 + yYb2O3 (x = 0, y = 0; x = 0.004, y = 0; x = 0, y = 0.05 and x = 0.004, y = 0.05 per moles). The samples were synthesized by the conventional melt quenching method. The optical absorption and emission measurements were conducted at room temperature to determine the spectral properties of lanthanides doped zinc tellurite glasses and, to study the energy transfer processes between dopant lanthanide ions. The band gap energies for both direct and indirect possible transitions and the Urbach energies were measured from the absorption spectra. The absorption spectra of the samples were analyzed by using the Judd-Ofelt approach. The effect of the ytterbium ions on the emission properties of erbium ions was investigated and the energy transfer processes between dopant ions were studied by measuring the up-conversion emission properties of the materials. The color quality parameters of obtained visible up-conversion emission were also determined as well as possibility of using the Er3 + glasses as erbium doped fiber amplifiers at 1.55 μm in infrared emission region.

Gamma radiation induced changes in nuclear waste glass containing Eu

NASA Astrophysics Data System (ADS)

Mohapatra, M.; Kadam, R. M.; Mishra, R. K.; Kaushik, C. P.; Tomar, B. S.; Godbole, S. V.

2011-10-01

Gamma radiation induced changes were investigated in sodium-barium borosilicate glasses containing Eu. The glass composition was similar to that of nuclear waste glasses used for vitrifying Trombay research reactor nuclear waste at Bhabha Atomic Research Centre, India. Photoluminescence (PL) and electron paramagnetic resonance (EPR) techniques were used to study the speciation of the rare earth (RE) ion in the matrix before and after gamma irradiation. Judd-Ofelt ( J- O) analyses of the emission spectra were done before and after irradiation. The spin counting technique was employed to quantify the number of defect centres formed in the glass at the highest gamma dose studied. PL data suggested the stabilisation of the trivalent RE ion in the borosilicate glass matrix both before and after irradiation. It was also observed that, the RE ion distributes itself in two different environments in the irradiated glass. From the EPR data it was observed that, boron oxygen hole centre based radicals are the predominant defect centres produced in the glass after irradiation along with small amount of E’ centres. From the spin counting studies the concentration of defect centres in the glass was calculated to be 350 ppm at 900 kGy. This indicated the fact that bulk of the glass remained unaffected after gamma irradiation up to 900 kGy.

Optical properties of Nd3+ doped bismuth zinc borate glasses.

PubMed

Shanmugavelu, B; Venkatramu, V; Ravi Kanth Kumar, V V

2014-03-25

Glasses with compositions of (100-x) (Bi2ZnOB2O6) -x Nd2O3 (where x=0.1, 0.3, 0.5, 1 and 2 mol%) were prepared by melt quenching method and characterized through optical absorption, emission and decay curve measurements. Optical absorption spectra have been analyzed using Judd-Ofelt theory. The emission spectra exhibit three peaks at 919, 1063 and 1337 nm corresponding to (4)F3/2 to (4)I9/2, (4)I11/2 and (4)I13/2 transitions in the near infrared region. The emission intensity of the (4)F3/2 to (4)I11/2 transition increases with increase of Nd(3+) concentration up to 1 mol% and then concentration quenching is observed for 2 mol% of Nd(3+) concentration. The lifetimes for the (4)F3/2 level are found to decrease with increase in Nd2O3 concentration in the glasses. The decay curves of the glass up to 0.3 mol% of Nd(3+) exhibit single exponential nature and thereafter the curves become nonexponential nature (0.5, 1 and 2 mol%). The nonexponential curve has been fitted to the Inokuti-Hirayama model to understand the nature of energy transfer process. Copyright © 2013 Elsevier B.V. All rights reserved.

Spectroscopic investigations of Nd3+ doped flouro- and chloro-borate glasses.

PubMed

Mohan, Shaweta; Thind, Kulwant Singh; Sharma, Gopi; Gerward, Leif

2008-10-01

Spectroscopic and physical properties of Nd3+ doped sodium lead flouro- and chloro-borate glasses of the type 20NaX-30PbO-49.5B2O3-0.5Nd2O3 (X=F and Cl) have been investigated. Optical absorption spectra have been used to determine the Slater Condon (F2, F4, and F6), spin orbit xi4f and Racah parameters (E1, E2, and E3). The oscillator strengths and the intensity parameters Omega2, Omega4 and Omega6 have been determined by the Judd-Ofelt theory, which in turn provide the radiative transition probability (A), total transition probability (A(T)), radiative lifetime (tauR) and branching ratio (beta) for the fluorescent level 4F3/2. The lasing efficiency of the prepared glasses has been characterized by the spectroscopic quality factor (Omega4/Omega6), the value of which is in the range of 0.2-1.5, typical for Nd3+ in different laser hosts. Nephelauxetic effect results in a red shift in the energy levels of Nd3+ for chloroborate glass. The radiative transition probability of the potential lasing transition 4F3/2-->4I11/2 of Nd3+ ions is found to be higher for flouroborate as compared to chloroborate glass.

Atomic-Level Structure Studies of Rare-Earth Doped Sodium Phosphate Glasses Using High Energy X-Ray Diffraction and Complementary Techniques

NASA Astrophysics Data System (ADS)

Amir, Faisal

The atomic-scale structure of a series of (RE2 O3)x ( Na2O)y ( P2O5)1- x-y glasses (RE = Pr, Nd, Er) where has been characterized by high-energy X-ray diffraction technique (HEXRD). In addition, differential thermal analysis (DTA), Fourier transform infrared (FTIR) spectroscopy, and absorption and emission spectroscopy in visible and near IR ranges have been used as supplementary tools to validate structural features obtained from HEXRD techniques.Structural features such as inter-atomic distances and coordination numbers and their dependence on the concentration of RE 2 O3 have been obtained by analyzing pair distribution functions (PDF) extracted from diffraction data. Coordination numbers for P-O, Na-O, O-O, and P-P were found to be independent of the RE 2 O3 concentration. In contrast, the RE-O coordination number varies between ≈ 8 and 7.2 as the RE2 O3 concentration increases from 0.005 to 0.05. The variation of the bond distance between large rare-earth ions (Pr, Nd) and small rare-earth ion (Er) is approximately 0.2 A, which is attributed to lanthanide contraction. The Na-O coordination number in these glasses was observed to ≈ 5.0 as the RE2 O 3 content increases. The overlapping correlation of RE-O, Na-O, and O-O in the same vicinity makes it difficult to calculate these coordination numbers. DTA measurements were used for the investigation of thermal characteristics of glasses. From these measurements, it is evident that the glass transition temperature increases with increasing the RE2 O3 (RE=Pr, Er) content. FTIR was used to inspect the structural changes of the glasses. The doping of RE 2 O3 (RE=Pr, Er) induces depolymerization of the glasses at the Q3 tetrahedral sites. The forming of the ionic linkages between phosphate chains is attributed to the increase in non-bridging oxygen (NBO). The cross-linkages density (CLD) increases with the RE2 O3 (RE=Pr, Er) concentrations. Absorption spectra for x = 0.01 of Er 3+ and 0.005-0.05 for Nd3+ doped glasses have been analyzed using Judd-Ofelt (JO) theory. The JO parameters have been used to predict radiative properties of luminescent levels of Er3+ and Nd3+ ions. Comparatively large photoluminescence lifetime 13.76 msec (x = 0.01) for Er3+ and 476 microsec ( x = 0.005) for Nd3+ for the laser transition was observed. However, the quantum efficiency of the erbium doped glasses is ≈70 %. The influence of RE 3+ (RE = Er, Nd) doping concentration on the emission spectra and lifetimes was investigated wit the model proposed by Auzel's limited diffusion model, in order to study the concentration quenching effect on luminescence. In this model, the fitting of the fluorescence lifetime experimental data gives us a radiative lifetime (tau0) and quenching concentration (N0). For Neodymium glasses, tau0 = 467 microsec and N0 = 5.98 x 1020 ions/cm3 Nd3+ ion, and in erbium glasses, tau0 = 12.4 ms at N0= 1.57 x 1020 ions/cm3 for Er3+ ion. The Inokuti-Hirayama (IH) model has been applied to the non-exponential behavior of the decay profiles to investigate the mechanism involved in the energy transfer between the donors and acceptors. Emission spectra of rare earth phosphate glasses show that their fluorescence efficiency decreases with increasing rare-earth content even at relatively at low concentrations (0.005 < x < 0.05), suggesting that concentration quenching of lasing action may be present even at these concentrations.

Optical properties of Nd3+ doped barium lithium fluoroborate glasses for near-infrared (NIR) emission

NASA Astrophysics Data System (ADS)

Mariselvam, K.; Arun Kumar, R.; Suresh, K.

2018-04-01

The neodymium doped barium lithium fluoroborate (Nd3+: BLFB) glasses with the chemical composition (70-x) H3BO3 - 10 Li2CO3 - 10 BaCO3- 5 CaF2-5 ZnO - x Nd2O3 (where x = 0.05, 0.1, 0.25, 0.5, 1, 2 in wt %) have been prepared by the conventional melt quenching technique and characterised through optical absorption, near infrared emission and decay-time measurements. The x-ray diffraction studies confirm the amorphous nature of the prepared glasses. The optical absorption spectra and emission spectra were recorded in the wavelength ranges of 190-1100 nm. The optical band gap (Eg) and Urbach energy (ΔE) values were calculated from the absorption spectra. The Judd-Ofelt intensity parameters were determined from the systematic analysis of the absorption spectrum of neodymium ions in the prepared glasses. The emission spectra exhibited three prominent peaks at 874, 1057, 1331 nm corresponding to the 4F3/2 → 4I9/2, 11/2, 13/2 transitions levels respectively in the near infrared region. The emission intensity of the 4F3/2 → 4I11/2 transition increases with the increase in neodymium concentration up to 0.5 wt% and the concentration quenching mechanism was observed for 1 wt% and 2 wt% concentrations. The lifetime of the 4F3/2 level was found to decrease with increasing Nd3+ ion concentration. The nature of energy transfer process was a single exponential curve which was studied for all the glasses and analysed.

Visible upconversion emission and non-radiative direct Yb 3+ to Er 3+ energy transfer processes in nanocrystalline ZrO 2:Yb 3+,Er 3+

NASA Astrophysics Data System (ADS)

Diaz-Torres, L. A.; Meza, O.; Solis, D.; Salas, P.; De la Rosa, E.

2011-06-01

Wide band gap Yb 3+ and Er 3+ codoped ZrO 2 nanocrystals have been synthesized by a modified sol-gel method. Under 967 nm excitation strong green and red upconversion emission is observed for several Er 3+ to Yb 3+ ions concentration ratios. A simple microscopic rate equation model is used to study the effects of non-radiative direct Yb 3+ to Er 3+ energy transfer processes on the visible and near infrared fluorescence decay trends of both Er 3+ and Yb 3+ ions. The microscopic rate equation model takes into account the crystalline phase as well as the size of nanocrystals. Nanocrystals phase and size were estimated from XRD patterns. The rate equation model succeeds to fit simultaneously all visible and near infrared fluorescence decay profiles. The dipole-dipole interaction parameters that drive the non-radiative energy transfer processes depend on doping concentration due to crystallite phase changes. In addition the non-radiative relaxation rate ( 4I11/2→ 4I13/2) is found to be greater than that estimated by the Judd-Ofelt parameters due to the action of surface impurities. Results suggest that non-radiative direct Yb 3+ to Er 3+ energy transfer processes in ZrO 2:Yb,Er are extremely efficient.

Sensitizing effect of Ho3+ on the Er3+: 2.7 μm-emission in fluoride glass

NASA Astrophysics Data System (ADS)

Huang, Feifei; Li, Xia; Liu, Xueqiang; Zhang, Junjie; Hu, Lili; Chen, Danping

2014-03-01

The fluorescence properties of 2.7 μm emission and energy transfer mechanism of Ho3+/Er3+ co-doped fluoride glass (ZBYA) have been investigated in the present paper. Ho3+ strengthens the Er3+: 2.7 μm emission in the ZBYA glasses due to the energy transfer from Er3+ to Ho3+, while the 1.5 μm emission decreases dramatically. The optimized concentration ratio of Er3+ to Ho3+ is found to be 1:1 in our glass system. The absorption and emission spectra are tested and the sample possesses large emission cross section (16.5 × 10-21 cm2) around 2.7 μm along with larger radiative transition probability (25.11 S-1) on the basis of Judd-Ofelt and Fuchtbauer-Ladenburg theories. Additionally, the energy transfer microparameters are calculated using Förster-Dexter theory and the result shows the energy transfer coefficient of Er3+:4I13/2 → Ho3+:5I7 is 24 times larger than that of Er3+:4I11/2 → Ho3+:5I6. Our results show that Er3+: 2.7 μm emission can be sensitized by Ho3+ efficiently, and this Er3+/Ho3+-codoped fluoride glasses might have potential application in mid-infrared lasers.

The effects of Nd2O3 concentration in the laser emission of TeO2-ZnO glasses

NASA Astrophysics Data System (ADS)

Moreira, L. M.; Anjos, V.; Bell, M. J. V.; Ramos, C. A. R.; Kassab, L. R. P.; Doualan, D. J. L.; Camy, P.; Moncorgé, R.

2016-08-01

The present work reports the modification introduced by different Nd2O3 concentration on optical properties and the laser operation of Nd3+ doped (TeO2-ZnO) bulk tellurite glass. The spectroscopic data are analyzed within the Judd Ofelt formalism framework and the results are compared to the fluorescence lifetime and emission measurements to derive values for the quantum efficiency and the stimulated emission cross section of the considered 4F3/2 → 4I11/2 infrared laser transition around 1062.5 nm. Continuous-wave laser action is achieved with this bulk tellurite glass by pumping the sample inside a standard plan-concave mirror laser cavity with different output couplers. It is possible to observe coherent emission only for the lower concentration (0.5%(wt.) of Nd2 O3). Also laser action could only be observed for this sample with threshold pump power of 73 mW associated with a laser slope efficiency of 8% for an output coupler transmission of 4% indicating that TeO2-ZnO are potential materials for laser action. The results presented in this work together with those previously reported with higher concentration (1.0% (wt) of Nd2O3) determine the adequate Nd2O3 concentration for laser action and guide the correct experimental procedure for TeO2-ZnO glasses preparation.

Spectroscopic properties of Er3+-doped fluorotellurite glasses containing various modifiers

NASA Astrophysics Data System (ADS)

Burtan-Gwizdała, Bożena; Reben, Manuela; Cisowski, Jan; Grelowska, Iwona; Yousef, El Sayed; Algarni, Hamed; Lisiecki, Radosław; Nosidlak, Natalia

2017-11-01

We have investigated the optical and spectroscopic properties of new Er3+-doped fluorotellurite glasses with the basic molar composition 75%TeO2-10%P2O5-10%ZnO-5%PbF2, modified by replacing 5%TeO2 by four various metal oxides, namely MgO, PbO, SrO and CdO. The ellipsometric data have provided a Sellmeier-type dispersion relation of the refractive index of the investigated glasses. The optical absorption edge has been described within the Urbach approach, while the absorption and fluorescence spectra have been analyzed in terms of the standard Judd-Ofelt theory along with the photoluminescence decay of the 4I13/2 and 4S3/2 levels of the Er3+ ion. The absorption and emission spectra of the 4I15/2 ↔ 4I13/2 infrared transition have been analyzed within the McCumber theory to yield the peak emission cross-section and figure of merit (FOM) for the amplifier gain. It appears that the glass containing MgO as a modifier is characterized by the largest FOM suggesting that the fluorotellurite matrix with this oxide can be a good novel host for Er3+ ion doping. Finally, we propose a new simple method to calculate the mean transition energy of the McCumber approach as the arithmetic average of the barycenter wavenumbers of absorption and emission spectra.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, J.; Yang, D. L.; Gong, H.

Conventional visible and novel infrared (IR) emissions of Sm{sup 3+} in heavy-metal-gallate glasses (Li{sub 2}O-K{sub 2}O-BaO-PbO-Bi{sub 2}O{sub 3}-Ga{sub 2}O{sub 3}, LKBPBG for short) with low phonon energy have been observed. Judd-Ofelt parameters {Omega}{sub 2} (3.00x10{sup -20} cm{sup 2}), {Omega}{sub 4} (5.19x10{sup -20} cm{sup 2}), and {Omega}{sub 6} (1.69x10{sup -20} cm{sup 2}) indicate a higher asymmetry and stronger covalent environment in the optical glasses. For the visible fluorescence bands peaked at 564, 601, 648, and 710 nm, the maximum stimulated emission cross-sections ({sigma}{sub e}) were derived to be 1.35x10{sup -22}, 9.21x10{sup -22}, 9.58x10{sup -22}, and 3.91x10{sup -22} cm{sup 2}, respectively, themore » values are larger than those in phosphate, oxyfluoroborate, tellurite, and calibo glasses obviously. The observed 1185 nm IR emission lies in the low-loss window of telecommunication system, and the maximum value of {sigma}{sub e} for this band was obtained to be 6.09x10{sup -23} cm{sup 2}. The characterization of multichannel radiative transitions of Sm{sup 3+} in LKBPBG glasses is beneficial in exposing its potential applications in visible and IR optoelectronic devices.« less

Luminescent Eu3+ doped Al6Ge2O13 crystalline compounds obtained by the sol gel process for photonics

NASA Astrophysics Data System (ADS)

Maia, Lauro J. Q.; Faria Filho, Fausto M.; Gonçalves, Rogéria R.; Ribeiro, Sidney J. L.

2018-01-01

We synthesized pure and Eu3+ doped Al6Ge2O13 samples by an easy and low-cost sol-gel route using the GeO2, Al(NO3)3·9H2O and Eu(NO3)3·6H2O as precursors, tetramethylammonium hydroxide and ethanol as solvents. The Al6Ge2O13 crystalline phase possesses orthorhombic structure and is a potential host for rare earth ions, especially due to high aluminum concentration. Homogeneous and transparent sols and gels were obtained. The samples containing 1 mol% of Eu3+ were heat-treated at 1000 °C to eliminate organic compounds, providing high optical quality and structural purity. All materials were characterized by thermogravimetric and differential thermal analysis, X-ray diffraction, Fourier transform infrared spectroscopy, high resolution transmission electron microscopy, selected area electron diffraction, diffuse reflectance spectra in the ultraviolet-visible-near infrared regions and photoluminescence measurements. High purity of Eu3+ doped Al6Ge2O13 orthorhombic phase and well crystallized grain dimensions of around 100 nm was obtained with high red photoluminescence emission. The decay lifetime of 5D0 level from Eu3+ (the emission at 612 nm) was determined, being between 0.97 and 2.12 ms, and an average quantum efficiency of 54% was determined (considering the average experimental lifetime of 1.77 ms). Moreover, it was calculated and analyzed some parameters of Judd-Ofelt theory applied to Eu3+ emissions from Al6Ge2O13 host. The results show that Eu3+ doped Al6Ge2O13 crystalline compounds have large potential to be used in displays and LED devices.

Understanding the complexation of Eu3+ with potential ligands used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle: A luminescence investigation.

PubMed

Sengupta, Arijit; Kadam, R M

2017-02-15

A systematic photoluminescence based investigation was carried out to understand the complexation of Eu 3+ with different ligands (TBP: tri-n-butyl phosphate, DHOA: di-n-hexyl octanamide, Cyanex 923: tri-n-alkyl phosphine oxide and Cyanex 272: Bis (2,4,4 trimethyl) pentyl phosphinic acid) used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle. In case of TBP and DHOA complexes, 3 ligand molecules coordinated in monodentate fashion and 3 nitrate ion in bidentate fashion to Eu 3+ to satisfy the 9 coordination of Eu. In case of Cyanex 923 and Cyanex 272 complexes, 3 ligand molecules, 3 nitrate ion and 3 water molecules coordinated to Eu 3+ in monodentate fashion. The Eu complexes of TBP and DHOA were found to have D 3h local symmetry while that for Cyanex 923 and Cyanex 272 were C 3h . Judd-Ofelt analysis of these systems revealed that the covalency of EuO bond followed the trend DHOA>TBP>Cyanex 272>Cyanex 923. Different photophysical properties like radiative and non-radiative life time, branching ratio for different transitions, magnetic and electric dipole moment transition probabilities and quantum efficiency were also evaluated and compared for these systems. The magnetic dipole transition probability was found to be almost independent of ligand field perturbation while electric dipole transition probability for 5 D 0 - 7 F 2 transition was found to be hypersensitive with ligand field with a trend DHOA>TBP>Cyanex 272>Cyanex 923. Copyright © 2016 Elsevier B.V. All rights reserved.

Understanding the complexation of Eu3 + with potential ligands used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle: A luminescence investigation

NASA Astrophysics Data System (ADS)

Sengupta, Arijit; Kadam, R. M.

2017-02-01

A systematic photoluminescence based investigation was carried out to understand the complexation of Eu3 + with different ligands (TBP: tri-n-butyl phosphate, DHOA: di-n-hexyl octanamide, Cyanex 923: tri-n-alkyl phosphine oxide and Cyanex 272: Bis (2,4,4 trimethyl) pentyl phosphinic acid) used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle. In case of TBP and DHOA complexes, 3 ligand molecules coordinated in monodentate fashion and 3 nitrate ion in bidentate fashion to Eu3 + to satisfy the 9 coordination of Eu. In case of Cyanex 923 and Cyanex 272 complexes, 3 ligand molecules, 3 nitrate ion and 3 water molecules coordinated to Eu3 + in monodentate fashion. The Eu complexes of TBP and DHOA were found to have D3h local symmetry while that for Cyanex 923 and Cyanex 272 were C3h. Judd-Ofelt analysis of these systems revealed that the covalency of Eusbnd O bond followed the trend DHOA > TBP > Cyanex 272 > Cyanex 923. Different photophysical properties like radiative and non-radiative life time, branching ratio for different transitions, magnetic and electric dipole moment transition probabilities and quantum efficiency were also evaluated and compared for these systems. The magnetic dipole transition probability was found to be almost independent of ligand field perturbation while electric dipole transition probability for 5D0-7F2 transition was found to be hypersensitive with ligand field with a trend DHOA > TBP > Cyanex 272 > Cyanex 923. Supplementary Table 2: Determination of inner sphere water molecules from the different empirical formulae reported in the literature.

Spectroscopic characterisation of Er-doped LuVO4 single crystals

NASA Astrophysics Data System (ADS)

Lisiecki, R.; Dominiak-Dzik, G.; Solarz, P.; Strzęp, A.; Ryba-Romanowski, W.; Łukasiewicz, T.

2010-12-01

The LuVO4:Er single crystals were grown by the Czochralski technique. The crystal-field split energy levels of Er3+ ion were derived experimentally employing absorption and emission spectra measured at T=10 K. The Judd-Ofelt phenomenological method was used to estimate intensity parameters, radiative lifetimes and branching ratios of luminescence. The excited state dynamics of the LuVO4:Er systems was investigated and experimental lifetimes of emitting levels were measured. The emission cross section of the 4I13/2→4I15/2 transition in the infrared was calculated by the Füchtbauer-Ladenburg method. The gain cross section, estimated for several inverse-population parameters, allowed us to evaluate a potential laser activity of the LuVO4:Er system at 1.6 μm. Also, the potential range of the optical pumping was assessed based on absorption spectra achieved at the room temperature. The optical losses related to the green up-converted emission, encountered under the 978 nm excitation between 300 and 670 K were indicated and discussed. Spectroscopic peculiarities of the Er3+-doped LuVO4 crystal were discussed in relation to optical properties of the YVO4:Er and GdVO4:Er crystals. Taking into account the high quantum efficiency of the 4I13/2 level, and satisfactory absorption and emission features, the LuVO4:Er crystal can be considered as a promising active material for laser operation near 1.6 μm.

Spectroscopic investigations of neodymium doped barium bismuth fluoroborate glasses

NASA Astrophysics Data System (ADS)

Mariselvam, K.; Arun Kumar, R.; Manasa, P.

2018-06-01

A new series of neodymium doped barium bismuth fluoroborate glasses with the chemical composition of (70-x)H3BO3 + 5Bi2O3 + 10BaCO3 + 7.5CaF2 + 7.5ZnO + xNd2O3 (where x = 0.05, 0.1, 0.25, 0.5, 1, 2 (in wt.%) have been prepared by the conventional melt quenching method. The powder X-ray diffraction pattern confirms the amorphous nature of the prepared glasses. The Urbach energy reveals the minimum disorderness of the glass samples. Judd-Ofelt intensity parameters (Ωλ = 2, 4 and 6) were derived from the absorption spectrum and were used to calculate the emission properties. The near infrared emission spectra recorded with 808 nm laser diode excitation for different concentrations of Nd3+ ions and the emission for the 4F3/2 → 4I11/2 transition at 1060 nm found to be high intense. The measured decay curves for 4F3/2 fluorescent level exhibit single exponential nature with shortening of lifetime with increase in concentration. The laser parameters such as stimulated emission cross-section, branching ratios, gain band width and optical gain values are found to be high for BBFB:Nd3+ (0.5 wt%) glass. Hence, the results suggested that the present BBFB:Nd3+ (0.5 wt%) glass could be used as an efficient infrared laser source around 1.06 μm region.

Spectroscopic properties of Tm3+/Al3+ co-doped sol-gel silica glass

NASA Astrophysics Data System (ADS)

Wang, Xue; Lou, Fengguang; Wang, Shikai; Yu, Chunlei; Chen, Danping; Hu, Lili

2015-04-01

Tm3+/Al3+ co-doped silica glass was prepared by sol-gel method combined with high temperature sintering. Glasses with compositions of xTm2O3-15xAl2O3-(100 - 16x) SiO2 (in mol%, x = 0.1, 0.3, 0.5, 0.8 and 1.0) were prepared. The high thulium doped silica glass was realized. Their spectroscopic parameters were calculated and analyzed by Judd-Ofelt theory. Large absorption cross section (4.65 × 10-21 cm2 at 1668 nm) and stimulated emission cross section (6.00 × 10-21 cm2 at 1812 nm), as well as low hydroxyl content (0.180 cm-1), long fluorescence lifetime (834 μs at 1800 nm), large σem × τrad (30.05 × 10-21 cm2 ms) and large relative intensity ratio of the 1.8 μm (3F4 → 3H6) to 1.46 (3H4 → 3F4) emissions (90.33) are achieved in this Tm3+/Al3+ co-doped silica glasses. According to emission characteristics, the optimum thulium doping concentration is around 0.8 mol%. The cross relaxation (CR) between ground and excited states of Tm3+ ions was used to explain the optimum thulium doping concentration. These results suggest that the sol-gel method is an effective way to prepare Tm3+ doped silica glass with high Tm3+ doping and prospective spectroscopic properties.

Enhanced broadband near-infrared luminescence from Pr3+-doped tellurite glass with silver nanoparticles

NASA Astrophysics Data System (ADS)

Cheng, Pan; Zhou, Yaxun; Zhou, Minghan; Su, Xiue; Zhou, Zizhong; Yang, Gaobo

2017-11-01

Pr3+-doped tellurite glasses containing metallic silver NPs were synthesized by the conventional melt-quenching technique. Structural, thermal and optical properties of the synthesized glass samples were characterized by X-Ray diffraction (XRD) curves, Raman spectra, differential scanning calorimeter (DSC) curves, transmission electron microscopy (TEM) images, UV/Vis/NIR absorption and near-infrared fluorescence emission spectra. The XRD curves confirmed the amorphous structural nature of the synthesized glasses, the Raman spectra identified the presence of different vibrational groups, the DSC curves verified the good thermal stability, and the TEM images revealed the nucleated silver NPs with average diameter about 10 nm dispersed in the glass matrix and its surface Plasmon resonance (SPR) absorption band was located at around 510 nm. Besides, Judd-Ofelt intensity parameters Ωt (t = 2, 4, 6) and other important spectroscopic parameters like transition probability, radiative lifetime, branching ratio were calculated to evaluate the radiative properties of Pr3+ levels from the measured optical absorption spectra. It was found that Pr3+-doped tellurite glasses could emit an ultra-broadband fluorescence extending from 1250 to 1650 nm under the 488 nm excitation, and this fluorescence emission increased further with the introduction of silver NPs. The enhanced fluorescence was mainly attributed to the increased local electric field around Pr3+ induced by silver NPs. The present results demonstrate that Pr3+-Ag codoped tellurite glass is a promising candidate for the near-infrared band ultra-broadband fiber amplifiers covering the expanded low-loss communication window.

Structural and spectroscopic characteristics of Eu3+-doped tungsten phosphate glasses

NASA Astrophysics Data System (ADS)

Dousti, M. Reza; Poirier, Gael Yves; de Camargo, Andrea Simone Stucchi

2015-07-01

Tungsten based phosphate glasses are interesting non-crystalline materials, commonly known for photochromic and electrochromic effects, but also promising hosts for luminescent trivalent rare earth ions. Despite very few reports in the literature, association of the host´s functionalities with the efficient emissions of the dopant ions in the visible and near-infrared spectra could lead to novel applications. This work reports the preparation and characterization of glasses with the new composition 4(Sb2O3)96-x(50WO3 50NaPO3)xEu2O3 where x = 0, 0.1, 0.25, 0.5 and 1.0 mol%, obtained by the melt quenching technique. The glasses present large density (∼4.6 g cm-3), high glass transition temperature (∼480 °C) and high thermal stability against crystallization. Upon excitation at 464 nm, the characteristic emissions of Eu3+ ions in the red spectral region are observed with high intensity. The Judd-Ofelt intensity parameters Ω2 = 6.86 × 10-20, Ω4 = 3.22 × 10-20 and Ω6 = 8.2 × 10-20 cm2 were calculated from the emission spectra and found to be higher than those reported for other phosphate glass compositions. An average excited state lifetime value of 1.2 ms, was determined by fitting the luminescence decay curves with single exponential functions and it is comparable or higher than those of other oxide glasses.

Spectroscopic investigations of Nd3+ doped Lithium Lead Alumino Borate glasses for 1.06 μm laser applications

NASA Astrophysics Data System (ADS)

Deopa, Nisha; Rao, A. S.; Gupta, Mohini; Vijaya Prakash, G.

2018-01-01

Neodymium doped lithium lead alumino borate glasses were synthesized with the molar composition 10Li2Osbnd 10PbOsbnd (10-x) Al2O3sbnd 70B2O3sbnd x Nd2O3 (where, x = 0.1, 0.5, 1.0, 1.5, 2.0 and 2.5 mol %) via conventional melt quenching technique to understand their lasing potentialities using the absorption, emission and photoluminescence decay spectral measurements. The oscillator strengths measured from the absorption spectra were used to estimate the Judd-Ofelt intensity parameters using least square fitting procedure. The emission spectra recorded for the as-prepared glasses under investigation exhibit two emission transitions 4F3/2 → 4I11/2 (1063 nm) and 4F3/2 → 4I9/2 (1350 nm) for which radiative parameters have been evaluated. The emission intensity increases with increase in Nd3+ ion concentration up to 1 mol % and beyond concentration quenching took place. The decay profile shows single exponential nature for lower Nd3+ ion concentration and non-exponential for higher concentration. To elucidate the nature of energy transfer process, the non-exponential decay curves were well fitted to Inokuti-Hirayama model. The relatively higher values of emission cross-sections, branching ratios and quantum efficiency values obtained for 1.0 mol% of Nd3+ ions in LiPbAlB glass suggests it's aptness in generating lasing action at 1063 nm in NIR region.

The topical application of low-temperature argon plasma enhances the anti-inflammatory effect of Jaun-ointment on DNCB-induced NC/Nga mice.

PubMed

Choi, Jeong-Hae; Song, Yeon-Suk; Lee, Hae-June; Kim, Gyoo-Cheon; Hong, Jin-Woo

2017-06-27

Jaun-ointment (JO), also known as Shiunko in Japan, is one of the most popular medicinal formulae used in Korean traditional medicine for the external treatment of skin wound and inflammatory skin conditions. Since JO is composed of crude mixture of two herbal extracts (radix of Lithospermum erythrorhizon Siebold & Zucc and Angelica gigas Nakai), those been proved its anti-inflammatory activities in-vitro and in-vivo, JO has been expected as a good alternative treatment option for atopic dermatitis (AD). However, due to the lack of strategies for the penetrating methods of JO's various anti-inflammatory elements into the skin, an effective and safe transdermal drug delivery system needs to be determined. Here, low-temperature argon plasma (LTAP) was adopted as an ancillary partner of topically applied JO in a mice model of AD and the effectiveness was examined. Dorsal skins of NC/Nga mice were challenged with DNCB (2,4-dinitrochlorobenzene) to induce AD. AD-like skin lesions were treated with JO alone, or in combination with LTAP. Inflammatory activity in the skin tissues was evaluated by histological analysis and several molecular biological tests. LTAP enhanced the effect of JO on AD-like skin lesion. Topical application of JO partially inhibited the development of DNCB-induced AD, shown by the moderate reduction of eosinophil homing and pro-inflammatory cytokine level. Combined treatment of JO and LTAP dramatically inhibited AD phenotypes. Interestingly, treatment with JO alone did not affect the activity of nuclear factor (NF)κB/RelA in the skin, but combined treatment of LTAP-JO blocked DCNB-mediated NFκB/RelA activation. LTAP markedly enhanced the anti-inflammatory activity of JO on AD-like skin lesions. The effect of LTAP may be attributed to enhancement of drug penetration and regulation of NFκB activity. Therefore, the combination treatment of JO and LTAP could be a potential strategy for the treatment of AD.

Evaluation of jojoba oil as a low-energy fat. 2. Intestinal transit time, stomach emptying and digestibility in short-term feeding studies in rats.

PubMed

Verschuren, P M; Nugteren, D H

1989-01-01

The influence of jojoba oil (JO) incorporation in the diet on stomach emptying and intestinal transit time, and the digestion and absorption of JO were investigated in short-term feeding studies in rats. The animals were fed purified diets containing 18% (w/w) fat, of which half consisted of a mixture of lard and sunflower seed oil (SF) supplemented with an equivalent amount of JO. The control animals were fed a mixture of lard and SF (18%). No treatment-related differences were observed in the rate of stomach emptying or the intestinal transit time. Comparative lipid analysis of lymph, intestinal content, intestinal mucosa and faeces indicated that most of the ingested JO was degraded and absorbed. Part of the JO was present as wax ester in the lymph. Hydrolysis of JO was much slower than that of triacylglycerols and continued in the alimentary tract beyond the small intestine due to bacterial processes. JO did not influence the absorption of the conventional fat.

Synthesis of Systemic Functional Theory & Dynamical Systems Theory for Socio-Cultural Modeling

DTIC Science & Technology

2012-05-07

Kevin Judd Email: Kevin.Judd@uwa.edu.au Institution: University of Western Australia Mailing Address: School of Mathematics and Statistics...Performance: 6 May 2010 - 5 May 2012 Note: Kevin Judd was on extended medical leave in 2011. He did not contribute to the project during 2011-2012...the project. Marissa E Kwan Lin was the Research Associate for the project. Report Documentation Page Form ApprovedOMB No. 0704-0188 Public

A meta-analysis and systematic review of reactivity to judgements of learning.

PubMed

Double, Kit S; Birney, Damian P; Walker, Sarah A

2018-07-01

Judgements of learning (JoL) are often used in memory research as a means for assessing an individual's metacognitive beliefs about their learning. JoL have been shown to reliably predict performance as well as learning behaviours and decisions . Participants may, however, modify their behaviour in response to performing JoL. There has, however, been little consensus as to the reliability and direction of the effect. We report on a meta-analyses that assesses the evidence that memory performance is reactive to JoL. The results indicate that overall providing JoL does not have a significant effect on memory performance (g = 0.054, 95% CI -0.027 to 0.135). However, sub-groups analysis showed that this effect depends on the nature of the stimuli to be recalled, with moderate positive reactivity observed for related word pairs (g = 0.323, 95% CI 0.083 to 0.563) and word lists (g = 0.384, 95% CI 0.146 to 0.622) but no reactivity when pairs were unrelated or a mixture of related and unrelated pairs. These results indicate that researchers should be aware that eliciting JoL may well influence participants' underlying encoding processes, especially when using related word pairs or word lists.

Investigation of the Fisheries of Africa, Buck, and Judd Lakes, Louisiana.

DTIC Science & Technology

1987-10-01

D-A188 978 INVESTIGATION OF THE FISHERIES VVW NJ 7 LAKES LOUISIA A(U) ARMY ENGINEER UATERWiAYS EXPERIMENT STATION VICKSBURG MS ENVIR L G SANDERS ET...MISCELLANEOUS PAPER EL-87-10 INVESTIGATION OF THE FISHERIES OF AFRICA, S BUCK, AND JUDD LAKES, LOUISIANA by AD-A188 978 Larry G. Sanders, John A...0060 ELEMENT NO. NO NO. rCCESSION NO 11 TITLE (Include Security Classification) Investigation of the Fisheries of Africa, Buck, and Judd Lakes

Bright up-conversion white light emission from Er3+ doped lithium fluoro zinc borate glasses for photonic applications

NASA Astrophysics Data System (ADS)

Vijayalakshmi, L.; Naveen Kumar, K.; Rao, K. Srinivasa; Hwang, Pyung

2018-03-01

Various concentrations of Er3+ (0.3, 0.5, 1.0 and 1.5 mol %) doped lithium fluoro zinc borate glasses were synthesized by a traditional melt quenching method. XRD, FTIR and FESEM have been employed to analyze the structural, compositional and morphological analysis respectively. Judd-Ofelt theory has been employed to analyze the intensity parameters (Ωλ, λ = 2, 4 and 6) which can be used to estimate the radiative properties of fluorescent levels of Er3+. We have been observed a strong NIR emission peak at 1.53 μm (4I13/2 → 4I15/2) under the excitation of 980 nm from Er3+: LBZ glasses. Nevertheless, the NIR emission is remarkably enhanced by increasing the Er3+ ions concentration until the optimized concentration of 0.5 mol%. The lifetime of the excited level of 4I13/2 in the NIR emission transition is evaluated and it is found to be1.22 ms from the decay analysis of 0.5 mol% Er3+: LBZ glass. Apart from the NIR emission, a bright up-conversion green emission is observed at 544 nm (4S3/2 → 4I15/2) along with an intense red emission at 659 nm (4F9/2 → 4I15/2) and a weak blue emission (2H9/2 → 4I15/2) under the excitation of 980 nm. Up-conversion emission features were significantly enhanced with increasing the Er3+ concentration up to 1.0 mol%. The combination of the obtained up-conversion emission colors of green, red and blue could generate white light emission. The cool white-light emission from the optimized glass sample has been confirmed from the Commission International de I'Echairage (CIE) 1931 chromaticity diagram analysis and their correlated color temperature (CCT) values. Based on the NIR and up-conversion emission features, Er3+: LBZ glasses could be suggested as promising candidates for optical amplifiers, optical telecommunication windows and white light photonic applications.

40 CFR 81.320 - Maine.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., Coburn Street northwest to Mechanic Street, Mechanic Street west to Judd Street, Judd Street northeast to... circumscribe the area of high emission densities and ambient PM10 levels. (60 FR 2885, January 12, 1995) Maine...

Bruce D. Judd, FAIA, Photographer August 1997. VIEW OF LOS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Bruce D. Judd, FAIA, Photographer August 1997. VIEW OF LOS ANGELES CITY HALL SIXTH FLOOR NORTH OFFICE AREA, FACING NORTH - Los Angeles City Hall, 200 North Spring Street, Los Angeles, Los Angeles County, CA

Bruce D. Judd, FAIA, Photographer August 1997. DETAIL OF LOS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Bruce D. Judd, FAIA, Photographer August 1997. DETAIL OF LOS ANGELES CITY HALL SIXTH FLOOR NORTH OFFICE AREA WINDOW, FACING NORTHWEST - Los Angeles City Hall, 200 North Spring Street, Los Angeles, Los Angeles County, CA

Consistent Structural Integrity and Efficient Certification with Analysis. Volume 3: Appendices of Verification and Validation Examples, Correlation Factors, and Failure Criteria

DTIC Science & Technology

2005-05-01

TANK WALL.........................74 6 VERIFICATION - BONDED JOINT HOMOGENOUS ISOTROPIC AND ORTHOTROPIC DELALE & ERDOGAN PUBLICATION (SIX EXAMPLES...developed for verification of BondJo 87 6.3.2 Adhesive stress comparisons between BondJo, Ansys solid model FEA and Delale and Erdogan plate theory 88...comparisons for condition 1 91 6.3.6 Adhesive stress comparisons between BondJo, Ansys solid model FEA and Delale and Erdogan plate theory 92 x FIGURE

Effect of concentration variation on 2.0 µm emission of Ho3+-doped SiO2-Al2O3-Na2CO3-SrF2-CaF2 oxyfluorosilicate glasses

NASA Astrophysics Data System (ADS)

Gelija, Devarajulu; Borelli, Deva Prasad Raju

2018-02-01

The concentration variation of Ho3+ ion-doped SiO2-Al2O3-Na2CO3-SrF2-CaF2 glasses has been prepared by conventional melt quenching method. The thermal stability of 1 mol % of Ho3+-doped oxyfluorosilicate glass has been calculated using the differential thermal analysis (DTA) spectra. The phenomenological Judd-Ofelt intensity parameters Ωλ ( λ = 2, 4 and 6) were calculated for all concentrations of Ho3+ ions. The luminescence spectra in visible region of Ho3+ ion-doped glasses were recorded under the excitation wavelength of 452 nm. The spectra consists of several intense emission bands (5F4, 5S2) → 5I8 (547 nm), 5F3 → 5I8 (647 nm), 5F5 → 5I7 (660 nm) and (5F4, 5S2) → 5I7 (750 nm) in the range 500-780 nm. The fluorescence emission at ˜2.0 µm (5I7 → 5I8) was observed under the excitation of 488 nm Ar-ion laser. The stimulated emission cross section for 5I7 → 5I8 transition (˜2.0 µm) varies from 8.46 to 9.52 × 10-21 cm2, as calculated by the Fuchtbauer-Ladenburg (FL) theory. However, Mc-Cumber theory was used to calculate emission cross section values about 4.24-5.75 × 10-21 cm2 for the 5I7 → 5I8 transition in all concentrations of Ho3+-doped oxyfluorosilicate glasses. Therefore, these results reveal that the 0.5 mol % of Ho3+-doped oxyfluorosilicate glasses, exhibiting higher emission cross section, has potentially been used for laser applications at ˜ 2.0 µm.

Spectroscopy and enhanced frequency upconversion in Nd3+-Yb3+ codoped TPO glasses: energy transfer and NIR to visible upconverter.

PubMed

Azam, Mohd; Rai, Vineet Kumar; Mohanty, Deepak Kumar

2017-09-22

TeO 2 -Pb 3 O 4 (TPO) glasses codoped with Nd 3+ and Yb 3+ ions have been fabricated by conventional melting technique. The absorption, emission and excitation spectra of the samples have been recorded. The optical band gap in both the doped/codoped glasses is found to be ∼3.31 eV. Judd-Ofelt analysis has been carried out by using the absorption spectrum of 0.8 mol% Nd 3+ doped glass to determine the radiative properties viz radiative transition probabilities, branching ratios, radiative lifetimes, quality factor and emission cross sections of some emitting levels for Nd 3+ ions. The radiative transition probability for the 4 G 7/2  →  4 I 9/2 transition (∼1926 Hz) is found to be maximum compared to other 4 G 5/2  →  4 I 9/2 (∼1622 Hz) and 4 F 5/2  →  4 I 9/2 (∼865 Hz) transitions. Upconversion (UC) luminescence of the samples has been examined by the 980 nm CW diode laser excitation. Effect of addition of Yb 3+ ions in the Nd 3+ doped glasses on UC emission intensity has been discussed. The UC emission intensity corresponding to the green, red and NIR bands in the codoped glass has been enhanced by ∼17, ∼12 and ∼42 times as compared to that of the Nd 3+ singly doped glass. The quantum efficiency for the 4 G 7/2 level is found to be ∼32%. The nephelauxetic ratio, bonding parameter and covalency of Nd 3+ ions have been found positive which represents the covalent bonding between Nd 3+ ion and oxygen atom. The colour tunability from yellowish-green to dominant green region has been obtained in the optimized codoped TPO glass.

Spectroscopy and enhanced frequency upconversion in Nd3+-Yb3+ codoped TPO glasses: energy transfer and NIR to visible upconverter

NASA Astrophysics Data System (ADS)

Azam, Mohd; Rai, Vineet Kumar; Mohanty, Deepak Kumar

2017-09-01

TeO2-Pb3O4 (TPO) glasses codoped with Nd3+ and Yb3+ ions have been fabricated by conventional melting technique. The absorption, emission and excitation spectra of the samples have been recorded. The optical band gap in both the doped/codoped glasses is found to be ˜3.31 eV. Judd-Ofelt analysis has been carried out by using the absorption spectrum of 0.8 mol% Nd3+ doped glass to determine the radiative properties viz radiative transition probabilities, branching ratios, radiative lifetimes, quality factor and emission cross sections of some emitting levels for Nd3+ ions. The radiative transition probability for the 4G7/2 → 4I9/2 transition (˜1926 Hz) is found to be maximum compared to other 4G5/2 → 4I9/2 (˜1622 Hz) and 4F5/2 → 4I9/2 (˜865 Hz) transitions. Upconversion (UC) luminescence of the samples has been examined by the 980 nm CW diode laser excitation. Effect of addition of Yb3+ ions in the Nd3+ doped glasses on UC emission intensity has been discussed. The UC emission intensity corresponding to the green, red and NIR bands in the codoped glass has been enhanced by ˜17, ˜12 and ˜42 times as compared to that of the Nd3+ singly doped glass. The quantum efficiency for the 4G7/2 level is found to be ˜32%. The nephelauxetic ratio, bonding parameter and covalency of Nd3+ ions have been found positive which represents the covalent bonding between Nd3+ ion and oxygen atom. The colour tunability from yellowish-green to dominant green region has been obtained in the optimized codoped TPO glass.

Anti-Jo-1 antibody-positive patients show a characteristic necrotizing perifascicular myositis.

PubMed

Mescam-Mancini, Lénaig; Allenbach, Yves; Hervier, Baptiste; Devilliers, Hervé; Mariampillay, Kuberaka; Dubourg, Odile; Maisonobe, Thierry; Gherardi, Romain; Mezin, Paulette; Preusse, Corinna; Stenzel, Werner; Benveniste, Olivier

2015-09-01

Idiopathic inflammatory myopathies can be classified as polymyositis, dermatomyositis, immune-mediated necrotizing myopathy, sporadic inclusion body myositis or non-specific myositis. Anti-Jo-1 antibody-positive patients are assigned to either polymyositis or dermatomyositis suggesting overlapping pathological features. We aimed to determine if anti-Jo-1 antibody-positive myopathy has a specific morphological phenotype. In a series of 53 muscle biopsies of anti-Jo-1 antibody-positive patients, relevant descriptive criteria defining a characteristic morphological pattern were identified. They were tested in a second series of anti-Jo-1 antibody-positive patients and compared to 63 biopsies from patients suffering from other idiopathic inflammatory myopathies. In anti-Jo-1 antibody-positive patients, necrotic fibres, which strongly clustered in perifascicular regions, were frequently observed. Sarcolemmal complement deposition was detected specifically in perifascicular areas. Inflammation was mainly located in the perimysium and around vessels in 90.6%. Perimysial fragmentation was observed in 90% of cases. Major histocompatibility complex class I staining was diffusely positive, with a perifascicular reinforcement. Multivariate analysis showed that criteria defining perifascicular pathology: perifascicular necrosis, atrophy, and perimysial fragmentation allow the distinction of anti-Jo-1 antibody-positive patients, among patients suffering from other idiopathic inflammatory myopathies. Anti-Jo-1 antibody-positive patients displayed perifascicular necrosis, whereas dermatomyositis patients exhibited perifascicular atrophy. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The enhanced and broadband near-infrared emission in Pr3+/Nd3+ co-doped tellurite glass

NASA Astrophysics Data System (ADS)

Zhou, Zizhong; Zhou, Yaxun; Cheng, Pan; Zhou, Minghan; Su, Xiue; Li, Jun

2017-11-01

This paper reports an enhanced and broadband near-infrared fluorescence emission in the Pr3+/Nd3+ co-doped tellurite glass, which was prepared using melt-quenching technique. Under the excitation of 488 nm laser diode (LD), three near-infrared emission bands at around 0.9, 1.04 and 1.30 μm from 3P1,0 → 1G4, 1G4→3H4 and 1G4→3H5 radiative transitions respectively were observed in the Pr3+ single-doped glass, and the fluorescence intensities increased further with the introduction of Nd3+ ions, which is mainly attributed to the energy transfers from Nd3+ to Pr3+ emissions. Meanwhile, the spectral overlapping of Pr3+:1G4→3H4 and Nd3+:4F3/2 → 4I11/2 radiative transitions resulted in a broadband emission ranging from 1000 to 1100 nm, whose full-width at half-maximum (FWHM) reached about 66 nm. Additionally, the spectroscopic properties of Nd3+ and Pr3+ ions were analyzed using Judd-Ofelt theory and the thermal stability property of prepared glass was characterized by the differential scanning calorimeter (DSC) measurement, and larger than 134 °C for the difference ΔT(=Tx -Tg) was observed, which indicates its feasibility for later fiber drawing. The enhanced fluorescence and broadband emission indicate that Pr3+/Nd3+ co-doped tellurite glass can be applied in the near-infrared band tunable lasers and broadband optical amplifiers.

Synthesis and spectroscopic behavior of highly luminescent Eu 3+-dibenzoylmethanate (DBM) complexes with sulfoxide ligands

NASA Astrophysics Data System (ADS)

Niyama, E.; Brito, H. F.; Cremona, M.; Teotonio, E. E. S.; Reyes, R.; Brito, G. E. S.; Felinto, M. C. F. C.

2005-09-01

In this paper the synthesis, characterization and photoluminescent behavior of the [RE(DBM) 3L 2] complexes (RE = Gd and Eu) with a variety of sulfoxide ligands; L = benzyl sulfoxide (DBSO), methyl sulfoxide (DMSO), phenyl sulfoxide (DPSO) and p-tolyl sulfoxide (PTSO) have been investigated in solid state. The emission spectra of the Eu 3+-β-diketonate complexes show characteristics narrow bands arising from the 5D 0 → 7F J ( J = 0-4) transitions, which are split according to the selection rule for C n, C nv or C s site symmetries. The experimental Judd-Ofelt intensity parameters ( Ω2 and Ω4), radiative ( Arad) and non-radiative ( Anrad) decay rates, and R02 for the europium complexes have been determined and compared. The highest value of Ω2 (61.9 × 10 -20 cm 2) was obtained to the complex with PTSO ligand, indicating that Eu 3+ ion is in the highly polarizable chemical environment. The higher values of the experimental quantum yield ( q) and emission quantum efficiency of the emitter 5D 0 level ( η) for the Eu-complexes with DMSO, DBSO and PTSO sulfoxides suggest that these complexes are promising Light Conversion Molecular Devices (LCMDs). The lower value of quantum yield ( q = 1%), for the hydrated complex [Eu(DBM) 3(H 2O)], indicates that the luminescence quenching occurs via multiphonon relaxation by coupling with the OH-oscillators from water molecule coordinated to rare earth ion. The pure red emission of the Eu-complexes has been confirmed by ( x, y) color coordinates.

Bruce D. Judd, FAIA, Photographer August 1997. VIEW OF LOS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Bruce D. Judd, FAIA, Photographer August 1997. VIEW OF LOS ANGELES CITY HALL ELEVENTH FLOOR KITCHEN OF EXECUTIVE DINING AREA SHOWING ARCHED STRUCTURE, FACING NORTHWEST - Los Angeles City Hall, 200 North Spring Street, Los Angeles, Los Angeles County, CA

Joint-operation in water resources project in Indonesia: Integrated or non-integrated

NASA Astrophysics Data System (ADS)

Ophiyandri, Taufika; Istijono, Bambang; Hidayat, Benny

2017-11-01

The construction of large water resources infrastructure project often involved a joint-operation (JO) project between two or more construction companies. The form of JO can be grouped into two categories - an integrated type and a non-integrated type. This paper investigates the reason of forming a JO project made by companies. The specific advantages and problems of JO project is also analysed in this paper. In order to achieve the objectives, three water resources infrastructure projects were selected as case studies. Data was gathered by conducting 11 semi-structured interviews to project owners, contractor managers, and project staffs. Data was analysed by means of content analysis. It was found that the most fundamental factor to form a JO is to win a competition or tender. An integrated model is in favour because it can reduce overhead costs and has a simple management system, while a non-integrated model is selected because it can avoid a sleeping partner and make contractor more responsible for their own job.

Two-condition within-participant statistical mediation analysis: A path-analytic framework.

PubMed

Montoya, Amanda K; Hayes, Andrew F

2017-03-01

Researchers interested in testing mediation often use designs where participants are measured on a dependent variable Y and a mediator M in both of 2 different circumstances. The dominant approach to assessing mediation in such a design, proposed by Judd, Kenny, and McClelland (2001), relies on a series of hypothesis tests about components of the mediation model and is not based on an estimate of or formal inference about the indirect effect. In this article we recast Judd et al.'s approach in the path-analytic framework that is now commonly used in between-participant mediation analysis. By so doing, it is apparent how to estimate the indirect effect of a within-participant manipulation on some outcome through a mediator as the product of paths of influence. This path-analytic approach eliminates the need for discrete hypothesis tests about components of the model to support a claim of mediation, as Judd et al.'s method requires, because it relies only on an inference about the product of paths-the indirect effect. We generalize methods of inference for the indirect effect widely used in between-participant designs to this within-participant version of mediation analysis, including bootstrap confidence intervals and Monte Carlo confidence intervals. Using this path-analytic approach, we extend the method to models with multiple mediators operating in parallel and serially and discuss the comparison of indirect effects in these more complex models. We offer macros and code for SPSS, SAS, and Mplus that conduct these analyses. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Recycle Runway

ERIC Educational Resources Information Center

Stephens, Pam

2009-01-01

Nancy Judd has been called a folk artist, an outsider artist, and a designer--all characterizations that she tends to shirk. Perhaps if labels are needed, environmental artist educator is more appropriate. Judd lives and works in Santa Fe, New Mexico. She dedicates much of her time to creating art that raises public awareness of environmental…

Prognostic factors in a cohort of antisynthetase syndrome (ASS): serologic profile is associated with mortality in patients with interstitial lung disease (ILD).

PubMed

Rojas-Serrano, Jorge; Herrera-Bringas, Denisse; Mejía, Mayra; Rivero, Hermes; Mateos-Toledo, Heidegger; Figueroa, José E

2015-09-01

The objectives of the present study were to compare the survival function of antisynthetase syndrome (ASS) Jo1-positive patients with ASS non-Jo1 patients, all with interstitial lung disease (ILD), and to evaluate other factors such as the extension of pulmonary disease and the time between the onset of symptoms and diagnosis and its association to survival in a cohort of ASS patients. Patients with ASS, all with ILD, were included. At the baseline, pulmonary function tests were realized and a high-resolution chest tomography was obtained; lung inflammation and fibrosis were measured with the Goh score and the Kazerooni index. The following autoantibodies were measured: Jo1, Ej, Oj, PL7, and PL12. Patients had to be positive for one of them in order to be included in the study. The survival function was estimated and compared with the log rank test, and the hazard ratio (HR) was estimated using Cox regression procedure. Forty-three patients were included, of which six patients died (14 %). Patients who died were different in comparison with survivors as regards the frequency of anti-Jo1 positivity: Survivors had anti-Jo1 autoantibodies more frequently (86 %) than patients who died (50 %). The univariate Cox regression analysis identified four variables associated with survival: Jo1 status, arthritis, extent of ground glass, and consolidation (inflammation) in high-resolution computed tomography (HRCT) and baseline forced vital capacity. The serological status of patients (Jo1-positive vs non-Jo1), the extent of lung inflammation in the HRCT scan, a low forced vital capacity, and arthritis are associated with survival in ASS patients.

Histogram analysis derived from apparent diffusion coefficient (ADC) is more sensitive to reflect serological parameters in myositis than conventional ADC analysis.

PubMed

Meyer, Hans Jonas; Emmer, Alexander; Kornhuber, Malte; Surov, Alexey

2018-05-01

Diffusion-weighted imaging (DWI) has the potential of being able to reflect histopathology architecture. A novel imaging approach, namely histogram analysis, is used to further characterize tissues on MRI. The aim of this study was to correlate histogram parameters derived from apparent diffusion coefficient (ADC) maps with serological parameters in myositis. 16 patients with autoimmune myositis were included in this retrospective study. DWI was obtained on a 1.5 T scanner by using the b-values of 0 and 1000 s mm - 2 . Histogram analysis was performed as a whole muscle measurement by using a custom-made Matlab-based application. The following ADC histogram parameters were estimated: ADCmean, ADCmax, ADCmin, ADCmedian, ADCmode, and the following percentiles ADCp10, ADCp25, ADCp75, ADCp90, as well histogram parameters kurtosis, skewness, and entropy. In all patients, the blood sample was acquired within 3 days to the MRI. The following serological parameters were estimated: alanine aminotransferase, aspartate aminotransferase, creatine kinase, lactate dehydrogenase, C-reactive protein (CRP) and myoglobin. All patients were screened for Jo1-autobodies. Kurtosis correlated inversely with CRP (p = -0.55 and 0.03). Furthermore, ADCp10 and ADCp90 values tended to correlate with creatine kinase (p = -0.43, 0.11, and p = -0.42, = 0.12 respectively). In addition, ADCmean, p10, p25, median, mode, and entropy were different between Jo1-positive and Jo1-negative patients. ADC histogram parameters are sensitive for detection of muscle alterations in myositis patients. Advances in knowledge: This study identified that kurtosis derived from ADC maps is associated with CRP in myositis patients. Furthermore, several ADC histogram parameters are statistically different between Jo1-positive and Jo1-negative patients.

Enhanced photoluminescence and thermal stability of divalent ions (Zn2+, Mg2+) assisted CaTiO3:Eu3+ perovskite phosphors for lighting applications

NASA Astrophysics Data System (ADS)

Singh, Dhananjay Kumar; Manam, J.

2018-03-01

Current study proposes the improved red emission of Zn2+ and Mg2+ ions incorporated CaTiO3:Eu3+ phosphors synthesized via the well-known solid-state reaction method. Under the 397 nm UV excitation, the Zn2+- and Mg2+-incorporated CaTiO3:0.15Eu3+ phosphor having orthorhombic structure with space group Pbnm exhibited an intense red emission at 619 nm. This can be credited to the hypersensitive 5D0 → 7F2 transition of Eu3+ ions, which is also indicative of the fact that the Eu3+ ions populated the non-inversion symmetry sites in the CaTiO3 lattices. The optimized composition CaTiO3:0.15Eu3+, 0.20Zn2+ and CaTiO3:0.15Eu3+, 0.10Mg2+ phosphors, pronounces in a magnificent enhancement of PL intensity by 5.5 and 2.5 times, respectively, as compared to CaTiO3:0.15 Eu3+ phosphor. From the temperature-dependent emission spectra, ΔEa were enunciated to be 0.101 and 0.086 eV for CaTiO3:0.15Eu3+, 0.20Zn2+ and CaTiO3:0.15Eu3+, 0.10Mg2+ phosphors, respectively, for thermal quenching. In addition, it can be better understood as related to the adequate thermal stability of 60% even at 450 and 420 K, respectively. Furthermore, the Judd-Ofelt theory was used to study the radiative intensity parameters of Eu3+ ions in the CaTiO3 lattices. The experimental results incited the bright prospects of synthesized ceramics as a promising candidate for lighting applications.

Spectroscopic study of trivalent praseodymium in barium yttrium fluoride

NASA Astrophysics Data System (ADS)

Bowlby, Brian Edward

1998-09-01

This work investigates the spectroscopic properties of trivalent praseodymium (Pr3+) in barium yttrium fluoride (BaY2F8). Two doping concentrations were studied: BaY2F8:Pr3+ (.3%) and BaY2F8:Pr3+ (1%). Absorption spectra were taken at 77K and 300K and these were then used to calculate the Judd-Ofelt coefficients for both samples. These coefficients were then used to calculate the theoretical lifetimes and radiative branching ratios for all manifolds. Continuous luminescence spectra and lifetime measurements were also performed, and from these, experimentally determined values for the branching ratio and lifetimes were determined. These were then compared to their theoretical counterparts. It was found that while the theory gave values that were qualitatively correct, the quantitative correlation between theory and experiment shows the complexity of the physical reality and the difficulty of synthesizing an encompassing theoretical model. Absorption spectra and continuous luminescence spectra were also used to determine the energy levels of all manifolds in both samples. A total of 59 energy levels in 11 manifolds were identified in the BaY2F8:Pr3+ (1%) sample, while 51 levels in 11 manifolds were identified in the BaY2F8:Pr3+ (.3%) sample. Finally, the effects of temperature on the line width and line position for several radiative transitions was studied. It was found that while most transitions exhibited the expected broadening and shifting towards longer wavelengths at higher temperatures (a 'red shift'), the transition from the 3P0 level to the 3H4 ground state showed a shift towards shorter wavelengths at higher temperature (a 'blue shift'). Again this highlights the complexity of the ion- host interaction.

Jojoba meal (Simmondsia chinensis) in the diet of broiler breeder pullets: physiological and endocrinological effects.

PubMed

Arnouts, S; Buyse, J; Cokelaere, M M; Decuypere, E

1993-09-01

The present studies evaluated the ability of jojoba meal (JO) to inhibit feed intake of broiler breeder pullets to limit body weight gain as recommended by the breeder company. A first experiment, using graded levels of JO supplementation (0 to 12%), was conducted to establish appropriate JO supplementation. Adequate reduction of growth rate was obtained with 4% JO supplementation. However, notwithstanding their similar growth rate, 4% JO chickens consumed considerably more feed compared with feed-restricted chickens. The dose-dependent impairment of feed intake with increasing levels of JO supplementation was also associated with increased plasma growth hormone and thyroxine and with decreased plasma insulin-like growth factor-I and triiodothyronine concentrations compared with 0% JO chickens. A second experiment included a pair-fed group. Notwithstanding their similar feed intake, 4% JO chickens gained significantly less body weight compared with their pair-fed counterparts. The 4% JO chickens also had a longer feed transit time per kilogram body weight. Again, circulating levels of the somatotrophic and thyrotrophic hormones were altered according to the dietary treatment. From all these observations, it was concluded that the growth retardation caused by JO supplementation was provoked by an inhibition of appetite linked with the simmondsin content of JO as well as by other antinutritional compounds affecting digestibility.

Effect of silver nanoparticles on the 1.53 μm fluorescence in Er3+/Yb3+ codoped tellurite glasses

NASA Astrophysics Data System (ADS)

Wu, Libo; Zhou, Yaxun; Zhou, Zizhong; Cheng, Pan; Huang, Bo; Yang, Fengjing; Li, Jun

2016-07-01

Improving the spectroscopic properties of rare earth (RE) doped glass materials is a challenging task. In the present work the metallic silver nanoparticles (Ag NPs) were embedded into Er3+/Yb3+ codoped tellurite glasses with composition TeO2-Bi2O3-TiO2, prepared using melt-quenching and subsequent heat-treated techniques, and the improved effect of Ag NPs on the 1.53 μm band fluorescence of Er3+ ions was investigated. About 24 h heat-treatment of Er3+/Yb3+ codoped tellurite glass containing 1 mol % amount of AgNO3 at the temperature 370 °C yielded the well-dispersed and near-spherical Ag NPs with ∼11.4 nm average diameter as evidenced by transmission electron microscopy (TEM) image. The intense 1.53 μm band fluorescence was observed in the prepared Er3+/Yb3+ codoped tellurite glasses under the excitation of 980 nm and was further improved with the presence of Ag NPs in the glass matrix, which is attributed to the enhanced local electric field around doped RE ions induced by Ag NPs and the possible energy transfer from Ag NPs to Er3+ ions. The enhanced local electric field was well demonstrated by comparing the variation of emission spectra of hypersensitive probe Eu3+ ions in tellurite glasses with and without Ag NPs. From the Judd-Ofelt analysis, it was also found that the value of Ω6 intensity parameter increased slightly with the increase of Ag NPs concentration in a certain range, also confirming the possibility of realizing strong fluorescence emission. In addition, the amorphous structural nature was demonstrated by the measured X-ray diffraction (XRD) patterns with no sharp diffraction peak. The enhanced 1.53 μm band fluorescence indicates that the Er3+/Yb3+ codoped tellurite glass with an appropriate amount of Ag NPs is a promising candidate for the development of Er3+-doped fiber amplifiers (EDFAs) applied in the WDM systems.

Full-profile fitting of emission spectrum to determine transition intensity parameters of Yb3 +:GdTaO4

NASA Astrophysics Data System (ADS)

Zhang, Qingli; Sun, Guihua; Ning, Kaijie; Shi, Chaoshu; Liu, Wenpeng; Sun, Dunlu; Yin, Shaotang

2016-11-01

The Judd-Ofelt theoretic transition intensity parameters of luminescence of rare-earth ions in solids are important for the quantitative analysis of luminescence. It is very difficult to determine them with emission or absorption spectra for a long time. A “full profile fitting” method to obtain in solids with its emission spectrum is proposed, in which the contribution of a radiative transition to the emission spectrum is expressed as the product of transition probability, line profile function, instrument measurement constant and transition center frequency or wavelength, and the whole experimental emission spectrum is the sum of all transitions. In this way, the emission spectrum is expressed as a function with the independent variables intensity parameters , full width at half maximum (FWHM) of profile functions, instrument measurement constant, wavelength, and the Huang-Rhys factor S if the lattice vibronic peaks in the emission spectrum should be considered. The ratios of the experimental to the calculated energy lifetimes are incorporated into the fitting function to remove the arbitrariness during fitting and other parameters. Employing this method obviates measurement of the absolute emission spectrum intensity. It also eliminates dependence upon the number of emission transition peaks. Every experiment point in emission spectra, which usually have at least hundreds of data points, is the function with variables and other parameters, so it is usually viable to determine and other parameters using a large number of experimental values. We applied this method to determine twenty-five of Yb3+ in GdTaO4. The calculated and experiment energy lifetimes, experimental and calculated emission spectrum are very consistent, indicating that it is viable to obtain the transition intensity parameters of rare-earth ions in solids by a full profile fitting to the ions’ emission spectrum. The calculated emission cross sections of Yb3+:GdTaO4 also indicate that the F-L formula gives larger values in the wavelength range with reabsorption. Project supported by the National Natural Science Foundation of China (Grant Nos. 51172236, 51502292, 51272254, 51102239, 61205173, and 61405206).

An Analysis of the Air Force Government Operated Civil Engineering Supply Store Logistic System: How Can It Be Improved?

DTIC Science & Technology

1990-09-01

6 Logistics Systems ............ 7 GOCESS Operation . . . . . . . ..... 9 Work Order Processing . . . . ... 12 Job Order Processing . . . . . . . . . . 14...orders and job orders to the Material Control Section will be discussed separately. Work Order Processing . Figure 2 illustrates typical WO processing...logistics function. The JO processing is similar. Job Order Processing . Figure 3 illustrates typical JO processing in a GOCESS operation. As with WOs, this

JoVE: the Journal of Visualized Experiments.

PubMed

Vardell, Emily

2015-01-01

The Journal of Visualized Experiments (JoVE) is the world's first scientific video journal and is designed to communicate research and scientific methods in an innovative, intuitive way. JoVE includes a wide range of biomedical videos, from biology to immunology and bioengineering to clinical and translation medicine. This column describes the browsing and searching capabilities of JoVE, as well as its additional features (including the JoVE Scientific Education Database designed for students in scientific fields).

Red-emitting LaOF:Eu{sup 3+} phosphors: Synthesis, structure and their Judd–Ofelt analysis for LED applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dhananjaya, N., E-mail: ndhananjayas@gmail.com; Shivakumara, C.; Saraf, Rohit

Highlights: • Red-emitting LaOF:Eu{sup 3+} phosphors were synthesized via facile solid state route. • Judd–Ofelt intensity parameters and radiative properties were determined from PL data. • CIE color coordinates of LaOF:Eu{sup 3+} phosphor is close to the commercial red phosphors. • Eu{sup 3+}-activated LaOF phosphor is a potential candidate for the production of red component in white LEDs. - Abstract: In the present study, we have synthesized a series of La{sub 1−x}Eu{sub x}OF (0.01 ≤ x ≤ 0.09) phosphors by the conventional solid-state reaction route at relatively low temperature (500 °C) and shorter duration of 2 h. The compounds weremore » crystallized in the rhombohedral structure with the space group R-3m (No. 166). Upon UV excitation (254 nm), the photoluminescence spectra exhibit characteristic luminescence {sup 5}D{sub 0} → {sup 7}F{sub J} (J = 1, 2, 3, and 4) intra-4f shell Eu{sup 3+} ion transitions. An intense red emission peak at 610 nm was observed due to electric dipole ({sup 5}D{sub 0} → {sup 7}F{sub 2}) transition. Judd–Ofelt theory was employed to evaluate various radiative parameters such as radiative emission rates, lifetime, branching and asymmetry ratios. CIE color coordinates confirmed the red emission of the phosphors. The luminescent results reveal that LaOF:Eu{sup 3+} phosphor can be used as potential candidate for developing red component in white LED applications.« less

Comparison on radiographic progression for 5 years between juvenile onset ankylosing spondylitis and adult onset ankylosing spondylitis: an observational study of the Korean SpondyloArthropathy Registry (OSKAR) data.

PubMed

Kim, Tae-Jong; Shin, Ji-Hui; Sung, Il-Hoon; Lee, Seunghun; Song, Yoonah; Kim, Tae-Hwan

2016-01-01

To evaluate differences in radiographic progression between adult-onset ankylosing spondylitis (AoAS) and juvenile-onset ankylosing spondylitis (JoAS). A total of 533 patients (418 patients with AoAS and 115 patients with JoAS) from the Observation Study of Korean spondyloArthropathy Registry (OSKAR) cohort were enrolled. All baseline OSKAR data were analysed in relation to disease onset and radiographic progression was analysed between the groups over 5 years. The modified Stoke AS Spinal Score (mSASSS) were used by two experienced radiologists. Clinical data were collected to investigate the associations between clinical factors and radiographic progression. Radiographic scores were compared using analysis of covariance model after adjusting for confounding factors. Inter-reader reliability for baseline mSASSS was very good. Inter-reader reliability for the changes in the mSASSS was also good. A significant difference in baseline mSASSS (mean ± SD) unit was detected between the AoAS and JoAS groups (18.1±17.4 vs. 14.3±13.8, p=0.015). We assessed the change in mSASSS to confirm whether age at onset affected radiographic progression. A simple comparison revealed a significant difference between changes on the mSASSS (mean ± SEM) between the JoAS and AoAS groups (1.75±0.71 vs. 3.77±0.56, p<0.001). After adjusting for multiple comparisons, change on the mSASSS remained lower in patients with JoAS than those with AoAS (0.28±1.33 vs. 4.08±0.62, p=0.016). Patients with JoAS had slower radiographic spinal damage progression over 5 years than those with AoAS.

A Guide for Measuring, Analyzing, and Evaluating Accelerations Recorded During Seakeeping Trials of High-Speed Craft

DTIC Science & Technology

2016-01-01

Smith, Strether. Digital Data Acquisition and Analysis, A short course presented at Sensors Expo Chicago , June 9, 2008. 11. Judd, Bob, Everything You...Forces, CG 731 2100 Second Street, SW STOP 356 Washington, DC 20593-7356 Attn: David Shepard United States Coast Guard RDT&E Division 2100 Second

Vesicular glutamate transporter 1 (VGLUT1)- and VGLUT2-immunopositive axon terminals on the rat jaw-closing and jaw-opening motoneurons.

PubMed

Park, Sook Kyung; Ko, Sang Jin; Paik, Sang Kyoo; Rah, Jong-Cheol; Lee, Kea Joo; Bae, Yong Chul

2018-02-23

To provide information on the glutamatergic synapses on the trigeminal motoneurons, which may be important for understanding the mechanism of control of jaw movements, we investigated the distribution of vesicular glutamate transporter (VGLUT)1-immunopositive (+) and VGLUT2 + axon terminals (boutons) on the rat jaw-closing (JC) and jaw-opening (JO) motoneurons, and their morphological determinants of synaptic strength by retrograde tracing, electron microscopic immunohistochemistry, and quantitative ultrastructural analysis. We found that (1) the large majority of VGLUT + boutons on JC and JO motoneurons were VGLUT2+, (2) the density of VGLUT1 + boutons terminating on JC motoneurons was significantly higher than that on JO motoneurons, (3) the density of VGLUT1 + boutons terminating on non-primary dendrites of JC motoneurons was significantly higher than that on somata or primary dendrites, whereas the density of VGLUT2 + boutons was not significantly different between JC and JO motoneurons and among various compartments of the postsynaptic neurons, and (4) the bouton volume, mitochondrial volume, and active zone area of the VGLUT1 + boutons forming synapses on JC motoneurons were significantly bigger than those of VGLUT2 + boutons. These findings suggest that JC and JO motoneurons receive glutamatergic input primarily from VGLUT2-expressing intrinsic neurons (premotoneurons), and may be controlled differently by neurons in the trigeminal mesencephalic nucleus and by glutamatergic premotoneurons.

Treating stimuli as a random factor in social psychology: a new and comprehensive solution to a pervasive but largely ignored problem.

PubMed

Judd, Charles M; Westfall, Jacob; Kenny, David A

2012-07-01

Throughout social and cognitive psychology, participants are routinely asked to respond in some way to experimental stimuli that are thought to represent categories of theoretical interest. For instance, in measures of implicit attitudes, participants are primed with pictures of specific African American and White stimulus persons sampled in some way from possible stimuli that might have been used. Yet seldom is the sampling of stimuli taken into account in the analysis of the resulting data, in spite of numerous warnings about the perils of ignoring stimulus variation (Clark, 1973; Kenny, 1985; Wells & Windschitl, 1999). Part of this failure to attend to stimulus variation is due to the demands imposed by traditional analysis of variance procedures for the analysis of data when both participants and stimuli are treated as random factors. In this article, we present a comprehensive solution using mixed models for the analysis of data with crossed random factors (e.g., participants and stimuli). We show the substantial biases inherent in analyses that ignore one or the other of the random factors, and we illustrate the substantial advantages of the mixed models approach with both hypothetical and actual, well-known data sets in social psychology (Bem, 2011; Blair, Chapleau, & Judd, 2005; Correll, Park, Judd, & Wittenbrink, 2002). PsycINFO Database Record (c) 2012 APA, all rights reserved

Optical spectra and emission characteristics of terbium-doped potassium-lead double chloride crystals (KPb2Cl5:Tb3+)

NASA Astrophysics Data System (ADS)

Tkachuk, A. M.; Ivanova, S. E.; Mirzaeva, A. A.; Isaenko, L. I.

2017-05-01

Optical transitions in KPb2Cl5:Tb3+ crystals are studied experimentally and theoretically. The absorption cross-section spectra are plotted and the oscillator strengths of transitions from the ground terbium state to excited multiplets are determined. Intensity parameters Ωt for KPC:Tb3+ are determined by the Judd-Ofelt method to be Ω2 = 2.70 × 10-20 cm2, Ω4 = 7.0 × 10-20 cm2, and Ω6 = 0.72 × 10-20 cm2. These values were used to calculate such characteristics of spontaneous radiative transitions as oscillator strengths, probabilities of radiative transitions, and radiative lifetimes. The emission spectra of KPb2Cl5:Tb3+ crystals upon UV excitation and the decay kinetics of luminescence from the excited 5 D 3 and 5 D 4 levels are studied experimentally, the lifetimes of these levels are determined, and the dependences of the rates of nonradiative relaxation from the excited 7 F j ( j = 0-5), 5 D 4, and 5 D 3 levels to lower-lying terbium levels are calculated. It is shown that the population of the 5 D 4 level in KPC:Tb3+ crystals occurs according to a cascade scheme, which leads to quenching of the 5 D 3 level. The calculated data agree well with the known experimental rates of multiphonon nonradiative transitions for Dy:KPC, Nd:KPC, Er:KPC, Tb:KPB, and Nd:KPB crystals. It is shown that transitions in the near-IR (3-6 μm) region in double halide crystals (MPb2Hal5) are almost unquenched and the rates of nonradiative relaxation of excited levels spaced by energy gaps Δ E ji > 1000 cm-1 are W ji NR < 103s-1. This circumstance suggests that it is possible to obtain stimulated emission in KPb2Cl5:RE3+ crystals in the IR spectral region up to 6 μm.

Effect of Ga2O3 on the spectroscopic properties of erbium-doped boro-bismuth glasses.

PubMed

Ling, Zhou; Ya-Xun, Zhou; Shi-Xun, Dai; Tie-Feng, Xu; Qiu-Hua, Nie; Xiang, Shen

2007-11-01

The spectroscopic properties and thermal stability of Er3+-doped Bi2O3-B2O3-Ga2O3 glasses are investigated experimentally. The effect of Ga2O3 content on absorption spectra, the Judd-Ofelt parameters Omega t (t=2, 4, 6), fluorescence spectra and the lifetimes of Er3+:4I 13/2 level are also investigated, and the stimulated emission cross-section is calculated from McCumber theory. With the increasing of Ga2O3 content in the glass composition, the Omega t (t=2, 4, 6) parameters, fluorescence full width at half maximum (FWHM) and the 4I 13/2 lifetimes of Er3+ first increase, reach its maximum at Ga2O3=8 mol.%, and then decrease. The results show that Er3+-doped 50Bi2O3-42B2O3-8Ga2O3 glass has the broadest FWHM (81nm) and large stimulated emission cross-section (1.03 x1 0(-20)cm2) in these glass samples. Compared with other glass hosts, the gain bandwidth properties of Er+3-doped Bi2O3-B2O3-Ga2O3 glass is better than tellurite, silicate, phosphate and germante glasses. In addition, the lifetime of 4I 13/2 level of Er(3+) in bismuth-based glass, compared with those in other glasses, is relative low due to the high-phonon energy of the B-O bond, the large refractive index of the host and the existence of OH* in the glass. At the same time, the glass thermal stability is improved in which the substitution of Ga2O3 for B2O3 strengthens the network structure. The suitability of bismuth-based glass as a host for a Er3+-doped broadband amplifier and its advantages over other glass hosts are also discussed.

Optical and spectroscopic properties of neodymium doped cadmium-sodium borate glasses

NASA Astrophysics Data System (ADS)

Mohan, Shaweta; Thind, Kulwant Singh

2017-10-01

Neodymium doped cadmium sodium borate glasses having composition xCdO-(40-x) Na2CO3-59.5H3BO3-0.5Nd2O3; x = 10, 20 and 30 mol% were prepared by conventional melt-quenching technique. X-ray diffraction studies confirmed the amorphous nature of the prepared glasses. Conventional methods were used to determine the physical properties such as density, molar volume, refractive index, and rare earth ion concentration. The Judd-Ofelt theory was applied on the optical absorption spectra of the glasses to evaluate the three phenomenological intensity parameters Ω2, Ω4 and Ω6. The calculated intensity parameters were further used to predict the radiative transition probability (A), radiative lifetime (τR) and branching ratio (βR) for the various fluorescent levels of Nd3+ ion in the prepared glass series. The effect of the compositional changes on the spectroscopic characteristics of Nd3+ ions have been studied and reported. The value of Ω2 is found to decrease with the decrease in the sodium content and the corresponding increase in the cadmium content. This can be ascribed to the changes in the asymmetry of the ligand field at the rare earth ion site and the change in rare earth oxygen (RE-O) covalency. Florescence spectra has been used to determine the peak wavelength (λp), effective line widths (Δλeff) and stimulated emission cross-section (σp) for the 4F3/2 → 4I9/2,4I11/2,4I13/2 transitions of the Nd3+ ion. The reasonably higher values of branching ratios and stimulated emission cross-section for the prepared glasses points towards the efficacy of these glasses as laser host materials. However, the glass with more sodium content is found to show better lasing properties.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou Bo; Pun, Edwin Yue-Bun; Yang Dianlai

Ho{sup 3+}-doped and Ho{sup 3+}/Yb{sup 3+}-codoped lead bismuth gallate (PBG) oxide glasses were prepared and their spectroscopic properties were investigated. The derived Judd-Ofelt intensity parameters (OMEGA{sub 2}=6.81x10{sup -20} cm{sup 2}, OMEGA{sub 4}=2.31x10{sup -20} cm{sup 2}, and OMEGA{sub 6}=0.67x10{sup -20} cm{sup 2}) indicate a higher asymmetry and stronger covalent environment for Ho{sup 3+} sites in PBG glass compared with those in tellurite, fluoride (ZBLAN), and some other lead-contained glasses. Intense frequency upconversion emissions peaking at 547, 662, and 756 nm as well as infrared emissions at 1.20 and 2.05 mum in Ho{sup 3+}/Yb{sup 3+}-codoped PBG glass were observed, confirming that energymore » transfer between Yb{sup 3+} and Ho{sup 3+} takes place, and a two-phonon-assisted energy transfer from Yb{sup 3+} to Ho{sup 3+} ions was determined by the calculation using phonon sideband theory. The 1.20 mum emission observed was primarily due to the weak multiphonon deexcitation originated from the small phonon energy of PBG glass (approx535 cm{sup -1}). A large product of emission cross-section and measured lifetime (9.93x10{sup -25} cm{sup 2} s) was obtained for the 1.20 mum emission and the gain coefficient dependence on wavelength with population inversion rate (P) was performed. The peak emission cross-section for 2.05 mum emission was calculated to be 4.75x10{sup -21} cm{sup 2}. The relative mechanism of Ho{sup 3+}-doped and Ho{sup 3+}/Yb{sup 3+}-codoped PBG glasses on their spectroscopic properties was also discussed. Our results suggest that Ho{sup 3+}/Yb{sup 3+}-doped PBG glasses are a good potential candidate for the frequency upconversion devices and infrared amplifiers/lasers.« less

Exploring the Neither in João Pedro Rodrigues and João Rui Guerra Da Mata's "A ultima vez que vi Macau"

ERIC Educational Resources Information Center

ten Haaf, Rachel

2017-01-01

Torn between two colonial powers, Macau has long existed as a peripheral region in Lusophone studies. This current study explores João Pedro Rodrigues and João Rui Guerra da Mata's 2012 film "A ultima vez que vi Macau". With a focus on a contemporary Macau that seeks to resolve its fundamental duality through investigation of gender,…

Increased sediment oxygen flux in lakes and reservoirs: The impact of hypolimnetic oxygenation

NASA Astrophysics Data System (ADS)

Bierlein, Kevin A.; Rezvani, Maryam; Socolofsky, Scott A.; Bryant, Lee D.; Wüest, Alfred; Little, John C.

2017-06-01

Hypolimnetic oxygenation is an increasingly common lake management strategy for mitigating hypoxia/anoxia and associated deleterious effects on water quality. A common effect of oxygenation is increased oxygen consumption in the hypolimnion and predicting the magnitude of this increase is the crux of effective oxygenation system design. Simultaneous measurements of sediment oxygen flux (JO2) and turbulence in the bottom boundary layer of two oxygenated lakes were used to investigate the impact of oxygenation on JO2. Oxygenation increased JO2 in both lakes by increasing the bulk oxygen concentration, which in turn steepens the diffusive gradient across the diffusive boundary layer. At high flow rates, the diffusive boundary layer thickness decreased as well. A transect along one of the lakes showed JO2 to be spatially quite variable, with near-field and far-field JO2 differing by a factor of 4. Using these in situ measurements, physical models of interfacial flux were compared to microprofile-derived JO2 to determine which models adequately predict JO2 in oxygenated lakes. Models based on friction velocity, turbulence dissipation rate, and the integral scale of turbulence agreed with microprofile-derived JO2 in both lakes. These models could potentially be used to predict oxygenation-induced oxygen flux and improve oxygenation system design methods for a broad range of reservoir systems.

Characterization and Peripheral Blood Biomarker Assessment of Jo-1 Antibody-Positive Interstitial Lung Disease

PubMed Central

Richards, Thomas J.; Eggebeen, Aaron; Gibson, Kevin; Yousem, Samuel; Fuhrman, Carl; Gochuico, Bernadette R.; Fertig, Noreen; Oddis, Chester V.; Kaminski, Naftali; Rosas, Ivan O.; Ascherman, Dana P.

2009-01-01

Objectives Combining clinical, radiographic, functional, and serum protein biomarker assessment, this study defines the prevalence and clinical characteristics of ILD in a large cohort of patients possessing anti-Jo-1 antibodies. Methods Clinical records, pulmonary function testing, and imaging studies determined the existence of ILD in anti-Jo-1 antibody positive (anti-Jo-1 Ab+) individuals accumulated in the University of Pittsburgh Myositis Database from 1982–2007. Multiplex ELISA of serum inflammatory markers, cytokines, chemokines, and matrix metalloproteinases in different patient subgroups then permitted assessment of serum proteins associated with anti-Jo-1 Ab+ ILD. Results Among 90 anti-Jo-1 Ab+ individuals with sufficient clinical, radiographic, and/or pulmonary function data, 77 (86%) met criteria for ILD. While computerized tomography scans revealed a variety of patterns suggestive of underlying UIP or NSIP, review of histopathologic abnormalities in a subset (n=22) of individuals undergoing open lung biopsy demonstrated a preponderance of UIP and DAD. Multiplex ELISA yielded statistically significant associations between Jo-1 Ab+ ILD and elevated serum levels of CRP, CXCL9, and CXCL10 that distinguished this subgroup from IPF and anti-SRP Ab+ myositis. Recursive partitioning further demonstrated that combinations of these and other serum protein biomarkers can distinguish these subgroups with high sensitivity and specificity. Conclusion In this large cohort of anti-Jo-1 Ab+ individuals, the incidence of ILD approaches 90%. Multiplex ELISA demonstrates disease-specific associations between Jo-1 Ab+ ILD and serum levels of CRP as well as the IFN-γ-inducible chemokines CXCL9 and CXCL10, highlighting the potential of this approach to define biologically active molecules contributing to the pathogenesis of myositis-associated ILD. PMID:19565490

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cazanave, Sophie; Vadrot, Nathalie; Tinel, Marina

Fas stimulation recruits neutrophils and activates macrophages that secrete tumor necrosis factor-{alpha} (TNF-{alpha}), which aggravates Fas-mediated liver injury. To determine whether nonsteroidal anti-inflammatory drugs modify these processes, we challenged 24-hour-fasted mice with the agonistic Jo2 anti-Fas antibody (4 {mu}g/mouse), and treated the animals 1 h later with saline or ibuprofen (250 mg/kg), a dual cyclooxygenase (COX)-1 and COX-2 inhibitor. Ibuprofen attenuated the Jo2-mediated recruitment/activation of myeloperoxidase-secreting neutrophils/macrophages in the liver, and attenuated the surge in serum TNF-{alpha}. Ibuprofen also minimized hepatic glutathione depletion, Bid truncation, caspase activation, outer mitochondrial membrane rupture, hepatocyte apoptosis and the increase in serum alanine aminotransferasemore » (ALT) activity 5 h after Jo2 administration, to finally decrease mouse mortality at later times. The concomitant administration of pentoxifylline (decreasing TNF-{alpha} secretion) and infliximab (trapping TNF-{alpha}) likewise attenuated the Jo2-mediated increase in TNF-{alpha}, the decrease in hepatic glutathione, and the increase in serum ALT activity 5 h after Jo2 administration. The concomitant administration of the COX-1 inhibitor, SC-560 (10 mg/kg) and the COX-2 inhibitor, celecoxib (40 mg/kg) 1 h after Jo2 administration, also decreased liver injury 5 h after Jo2 administration. In contrast, SC-560 (10 mg/kg) or celecoxib (40 or 160 mg/kg) given alone had no significant protective effects. In conclusion, secondary TNF-{alpha} secretion plays an important role in Jo2-mediated glutathione depletion and liver injury. The combined inhibition of COX-1 and COX-2 by ibuprofen attenuates TNF-{alpha} secretion, glutathione depletion, mitochondrial alterations, hepatic apoptosis and mortality in Jo2-treated fasted mice.« less

The clinical phenotype associated with myositis-specific and associated autoantibodies: a meta-analysis revisiting the so-called antisynthetase syndrome.

PubMed

Lega, Jean-Christophe; Fabien, Nicole; Reynaud, Quitterie; Durieu, Isabelle; Durupt, Stéphane; Dutertre, Marine; Cordier, Jean-François; Cottin, Vincent

2014-09-01

To describe the clinical spectrum associated with aminoacyl-transfer RNA synthetase (ARS) autoantibodies in patients with idiopathic inflammatory myositis defined according to Peter and Bohan's criteria. Cohort studies were selected from MEDLINE and Embase up to August 2013. Two investigators independently extracted data on study design, patient characteristics, and clinical features (interstitial lung disease [ILD], fever, mechanic's hands [MH], Raynaud's phenomenon [RPh], arthralgia, sclerodactyly, cancer and dermatomyositis-specific rash) according to the presence of myositis-specific (anti-aminoacyl-transfer RNA synthetase [ARS], anti-signal recognition particle [anti-SRP] and anti-Mi2) and myositis-associated (anti-PM/Scl, anti-U1-RNP and anti-Ku) autoantibodies. 27 studies (3487 patients) were included in the meta-analysis. Arthralgia (75%, CI 67-81) and ILD (69%, CI 63-74) were the most prevalent clinical signs associated with anti-ARS autoantibodies. Anti-Mi2 and anti-SRP autoantibodies were associated with few extramuscular signs. ARS autoantibodies were identified in 13% of patients with cancer-associated myositis (5-25). Patients with non-anti-Jo1 ARS had greater odds of presenting fever (RR 0.63, CI 0.52-0.90) and ILD (RR 0.87, CI 0.81-0.93) compared to those with anti-Jo1 autoantibodies. The frequencies of myositis (RR 1.60, CI 1.38-1.85), arthralgia (RR 1.52, CI 1.32-1.76) and MH (RR 1.47, CI 1.11-1.94) were almost 50% higher in patients with anti-Jo1 compared to non-anti-Jo1 ARS autoantibodies. Patients with anti-PM/Scl differed from those with anti-ARS autoantibodies by a greater prevalence of RPh (RR 0.70, CI 0.53-0.94) and sclerodactyly (RR 0.47, CI 0.25-0.89). ILD was less frequent in patients with anti-U1-RNP autoantibodies (RR 3.35, CI 1.07-10.43). No difference was observed between anti-ARS and myositis-associated autoantibodies for other outcomes. The presence of anti-ARS autoantibodies delimits a heterogeneous subset of patients with a high prevalence of myositis, MH, arthralgia in anti-Jo1 patients, and RPh and fever in non-anti-Jo1 patients. The clinical signs of populations positive for anti-PM/Scl and anti-ARS autoantibodies largely overlap, especially with regard to ILD, challenging the clinical delimitation of the antisynthetase syndrome. Copyright © 2014 Elsevier B.V. All rights reserved.

Daylighting Digital Dimmer SBIR Phase 2 Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Morgan

The primary focus of the Phase II Development is the implementation of two key technologies, Task To Wall (TTW) Control, and Wand Gesture light dimming control into an easy to use remote for SSL light control, the MoJo Remote. The MoJo Remote product family includes a battery powered wireless remote, a WiFi gateway as well as Mobile Applications for iOS and Android. Specific accomplishments during the second reporting period include: 1. Finalization and implementation of MoJo Remote Accelerometer and capacitive-touch based UI/UX, referred to as the Wand Gesture UI. 2. Issuance of Patent for Wand Gesture UI. 3. Industrial andmore » Mechanical Design for MoJo Remote and MoJo Gateway. 4. Task To Wall implementation and testing in MoJo Remote. 5. Zooming User Interface (ZUI) for the Mobile App implemented on both iOS and Andriod. 6. iOS Mobile app developed to beta level functionality. 7. Initial Development of the Android Mobile Application. 8. Closed loop color control at task (demonstrated at 2016 SSL R&D Workshop). 9. Task To Wall extended to Color Control, working in simulation. 10. Beta testing begun in Late 2017/Early 2018. The MoJo Remote integrates the Patented TTW Control and the Wand Gesture innovative User Interface, and is currently in Beta testing and on the path to commercialization.« less

Comparison of long-term outcome between anti-Jo1- and anti-PL7/PL12 positive patients with antisynthetase syndrome.

PubMed

Marie, I; Josse, S; Decaux, O; Dominique, S; Diot, E; Landron, C; Roblot, P; Jouneau, S; Hatron, P Y; Tiev, K P; Vittecoq, O; Noel, D; Mouthon, L; Menard, J-F; Jouen, F

2012-08-01

The aims of the present study were to: compare the characteristics between antisynthetase syndrome (ASS) patients with anti-Jo1 antibody and those with anti-PL7/PL12 antibody. The medical records of 95 consecutive patients with ASS were reviewed. Seventy-five of these patients had anti-Jo1 antibody; the other patients had anti-PL7 (n=15) or anti-PL12 (n=5) antibody. At ASS diagnosis, the prevalence of myalgia (p=0.007) and muscle weakness (p=0.02) was significantly lower in the group of anti-PL7/PL12-positive patients than in those with anti-Jo1 antibody; median value of CK (p=0.00003) was also lower in anti-PL7/PL12 patients. Anti-Jo1 positive patients developed more rarely myositis resolution (21.3% vs. 46.2%); in addition, the overall recurrence rate of myositis was higher in anti-Jo1 positive patients than in patients with anti-PL7/PL12 antibody (65.9% vs. 19.4%). Anti-Jo1-positive patients, compared with those with anti-PL7/PL12 antibody, more often experienced: joint involvement (63.3%vs. 40%) and cancer (13.3% vs. 5%). By contrast, anti-PL7/PL12 positive patients, compared with those with anti-Jo1 antibody, more commonly exhibited: ILD (90% vs. 68%); in anti-PL7/PL12 positive patients, ILD was more often symptomatic at diagnosis, and led more rarely to resolution of lung manifestations (5.6% vs. 29.4%). Finally, the group of anti-PL7/PL12 positive patients more commonly experienced gastrointestinal manifestations related to ASS (p=0.02). Taken together, although anti-Jo1 positive patients with ASS share some features with those with anti-PL7/PL12 antibody, they exhibit many differences regarding clinical phenotype and long-term outcome. Our study underscores that the presence of anti-Jo1 antibody results in more severe myositis, joint impairment and increased risk of cancer. On the other hand, the presence of anti-PL7/PL12 antibody is markedly associated with: early and severe ILD, and gastrointestinal complications. Thus, our study interestingly indicates that the finding for anti-Jo1 and anti-PL7/PL12 antibodies impacts both the long-term outcome and prognosis of patients with ASS. Copyright © 2012 Elsevier B.V. All rights reserved.

Japan's healthcare policy for the elderly through the concepts of self-help (Ji-jo), mutual aid (Go-jo), social solidarity care (Kyo-jo), and governmental care (Ko-jo).

PubMed

Sudo, Kyoko; Kobayashi, Jun; Noda, Shinichiro; Fukuda, Yoshiharu; Takahashi, Kenzo

2018-03-18

Elderly care is an emerging global issue threatening both developed and developing countries. The elderly in Japan increased to 26.7% of the population in 2015, and Japan is classified as a super-aged society. In this article, we introduce the financial aspects of the medical care and welfare services policy for the elderly in Japan. Japan's universal health insurance coverage system has been in place since 1961. Long-term care includes welfare services, which were separated from the medical care insurance scheme in 2000 when Japan was already recognized as an aging society. Since then, the percentage of the population over 65 has increased dramatically, with the productive-age population on the decrease. The Japanese government, therefore, is seeking to implement "The Community-based Integrated Care System" with the aim of building comprehensive up-to-the-end-of-life support services in each community. The system has four proposed elements: self-help (Ji-jo), mutual aid (Go-jo), social solidarity care (Kyo-jo), and government care (Ko-jo). From the financial perspective, as the government struggles against the financial burdens of an aging population, they are considering self-help and mutual aid. Based on Japan's present situation, both elements could lead to positive results. The Japanese government must also entrust the responsibility for implementing preventive support to municipalities through strongly required regional autonomy. As Japan has resolved this new challenge through several discussions over a long period of time, other aging countries could learn from the Japanese experience of solving barriers to healthcare policy for the elderly.

Prime Contract Awards Alphabetically by Contractor, by State or Country, and Place, FY 88. Part 4. (Burnside-Ott Avi. Training Ctr.-Colcom, Inc.)

DTIC Science & Technology

1988-01-01

AD-.A207 773 D DCMNAI 773I Form Approved DOCUMENTATION PAG . OMB No. 0704-0188 la . REPORT SECURITY CLASSIFICATION lb. RESIH CTIVE MARKINGS T1TneI1...CK00 dx co00 ~00 ~0w 06300-4 Iwo 6Ŕ L-4-0 W-4 W001 La IO000 W,4 wo woo WNCI wo WO00-4 I -JO -JO _300 -1.JW -.1N -acOO -a00 -JO _aOO -JO -J.O WO.J 3 0...30 300 I 3= I LA . I.. 0 1300 300I ( IlL. :40" IN (D 000 (0 -IN t-N PN00 NW) V Ch(0 N N0 WN NN- n 44൰cN N.o 0 0) WNal anW m&o W*00W 0)0 40 Nat 0)(to c

Benton Judgment of Line Orientation (JoLO) Test: A Brief and Useful Measure for Assessing Visuospatial Abilities in Manifest, but not Premanifest, Huntington's Disease.

PubMed

Corey-Bloom, Jody; Gluhm, Shea; Herndon, Andrew; Haque, Ameera S; Park, Sungmee; Gilbert, Paul E

2016-01-01

Visuospatial deficits have been described in Huntington's disease (HD); however, the extent of these deficits remains unclear. The Benton Judgment of Line Orientation (JoLO) Test, commonly used to assess visuospatial ability, requires minimal motor involvement. It has demonstrated sensitivity to visuospatial deficits in Parkinson's disease; however, few studies have examined performance on this test in HD. The objective of the current study was to assess visuospatial ability in premanifest and manifest HD using the JoLO. A global cognitive measure, the Mattis Dementia Rating Scale (DRS), was used to stratify manifest HD patients as mild (DRS ≥129) vs. moderate-severe (DRS ≤128). Fifty mild, 42 moderate-severe, and 30 premanifest HD subjects, as well as 35 matched controls, were administered the JoLO. HD Burden of Pathology (BOP) scores were used as a measure of disease severity. Results revealed that the total manifest HD sample (p <  0.001), in addition to the mild (p = 0.028), and moderate-severe (p <  0.001), but not premanifest, HD subjects scored significantly lower on the JoLO compared to normal controls. Our results suggest that the JoLO is useful for detecting visuospatial deficits across various stages of manifest HD. However, any visuospatial impairment that might be present during the premanifest stage of HD was not detected using the JoLO in the present sample.

Semantic Ambiguity and the Failure of Inhibition Hypothesis as an Explanation for Reading Errors in Deep Dyslexia

ERIC Educational Resources Information Center

Colangelo, A.; Buchanan, L.

2005-01-01

We report evidence for dissociation between explicit and implicit access to word representations in a deep dyslexic patient (JO). JO read aloud a series of ambiguous (e.g., bank) and unambiguous (e.g., food) words and performed a lexical decision task using these same items. When required to explicitly access the items (i.e., naming), JO showed…

Dynamic Range Compression in the Honey Bee Auditory System toward Waggle Dance Sounds

PubMed Central

Tsujiuchi, Seiya; Sivan-Loukianova, Elena; Eberl, Daniel F.; Kitagawa, Yasuo; Kadowaki, Tatsuhiko

2007-01-01

Honey bee foragers use a “waggle dance” to inform nestmates about direction and distance to locations of attractive food. The sound and air flows generated by dancer's wing and abdominal vibrations have been implicated as important cues, but the decoding mechanisms for these dance messages are poorly understood. To understand the neural mechanisms of honey bee dance communication, we analyzed the anatomy of antenna and Johnston's organ (JO) in the pedicel of the antenna, as well as the mechanical and neural response characteristics of antenna and JO to acoustic stimuli, respectively. The honey bee JO consists of about 300–320 scolopidia connected with about 48 cuticular “knobs” around the circumference of the pedicel. Each scolopidium contains bipolar sensory neurons with both type I and II cilia. The mechanical sensitivities of the antennal flagellum are specifically high in response to low but not high intensity stimuli of 265–350 Hz frequencies. The structural characteristics of antenna but not JO neurons seem to be responsible for the non-linear responses of the flagellum in contrast to mosquito and fruit fly. The honey bee flagellum is a sensitive movement detector responding to 20 nm tip displacement, which is comparable to female mosquito. Furthermore, the JO neurons have the ability to preserve both frequency and temporal information of acoustic stimuli including the “waggle dance” sound. Intriguingly, the response of JO neurons was found to be age-dependent, demonstrating that the dance communication is only possible between aged foragers. These results suggest that the matured honey bee antennae and JO neurons are best tuned to detect 250–300 Hz sound generated during “waggle dance” from the distance in a dark hive, and that sufficient responses of the JO neurons are obtained by reducing the mechanical sensitivity of the flagellum in a near-field of dancer. This nonlinear effect brings about dynamic range compression in the honey bee auditory system. PMID:17311102

Dynamic range compression in the honey bee auditory system toward waggle dance sounds.

PubMed

Tsujiuchi, Seiya; Sivan-Loukianova, Elena; Eberl, Daniel F; Kitagawa, Yasuo; Kadowaki, Tatsuhiko

2007-02-21

Honey bee foragers use a "waggle dance" to inform nestmates about direction and distance to locations of attractive food. The sound and air flows generated by dancer's wing and abdominal vibrations have been implicated as important cues, but the decoding mechanisms for these dance messages are poorly understood. To understand the neural mechanisms of honey bee dance communication, we analyzed the anatomy of antenna and Johnston's organ (JO) in the pedicel of the antenna, as well as the mechanical and neural response characteristics of antenna and JO to acoustic stimuli, respectively. The honey bee JO consists of about 300-320 scolopidia connected with about 48 cuticular "knobs" around the circumference of the pedicel. Each scolopidium contains bipolar sensory neurons with both type I and II cilia. The mechanical sensitivities of the antennal flagellum are specifically high in response to low but not high intensity stimuli of 265-350 Hz frequencies. The structural characteristics of antenna but not JO neurons seem to be responsible for the non-linear responses of the flagellum in contrast to mosquito and fruit fly. The honey bee flagellum is a sensitive movement detector responding to 20 nm tip displacement, which is comparable to female mosquito. Furthermore, the JO neurons have the ability to preserve both frequency and temporal information of acoustic stimuli including the "waggle dance" sound. Intriguingly, the response of JO neurons was found to be age-dependent, demonstrating that the dance communication is only possible between aged foragers. These results suggest that the matured honey bee antennae and JO neurons are best tuned to detect 250-300 Hz sound generated during "waggle dance" from the distance in a dark hive, and that sufficient responses of the JO neurons are obtained by reducing the mechanical sensitivity of the flagellum in a near-field of dancer. This nonlinear effect brings about dynamic range compression in the honey bee auditory system.

Looking like a criminal: stereotypical black facial features promote face source memory error.

PubMed

Kleider, Heather M; Cavrak, Sarah E; Knuycky, Leslie R

2012-11-01

The present studies tested whether African American face type (stereotypical or nonstereotypical) facilitated stereotype-consistent categorization, and whether that categorization influenced memory accuracy and errors. Previous studies have shown that stereotypically Black features are associated with crime and violence (e.g., Blair, Judd, & Chapleau Psychological Science 15:674-679, 2004; Blair, Judd, & Fallman Journal of Personality and Social Psychology 87:763-778, 2004; Blair, Judd, Sadler, & Jenkins Journal of Personality and Social Psychology 83:5-252002); here, we extended this finding to investigate whether there is a bias toward remembering and recategorizing stereotypical faces as criminals. Using category labels, consistent (or inconsistent) with race-based expectations, we tested whether face recognition and recategorization were driven by the similarity between a target's facial features and a stereotyped category (i.e., stereotypical Black faces associated with crime/violence). The results revealed that stereotypical faces were associated more often with a stereotype-consistent label (Study 1), were remembered and correctly recategorized as criminals (Studies 2-4), and were miscategorized as criminals when memory failed. These effects occurred regardless of race or gender. Together, these findings suggest that face types have strong category associations that can promote stereotype-motivated recognition errors. Implications for eyewitness accuracy are discussed.

Computing Support for Basic Research in Perception and Cognition.

DTIC Science & Technology

1987-08-31

learning occurs in the verbal domain as well as the spatial domain. David Knopman, Marilyn Hartman, and Mary Jo Nissan are preparing a written report of... Mary Jo Nissen, and Neal F. Viemeister Department of PsychoLogy University of Minnesota 75 East River Road Nlinneapol is, MN 55455 :1 August 1987 Interim...Laboratory directed by Neal F. Viemeister, Mary Jo Nissen’s Cognitive Psychology Laboratory, and the Psycholinguistics Laboratory directed by Charles

Stress Concentrations.

DTIC Science & Technology

1982-09-01

a joJo p~ ~qJO iju;~33 oa~u UO~u~aUuo3-s;JS I I awnh!d pu1 IuwLaqdsawq aqlI i~ pjO3U u L1 t 3AIWSOd NANOHS 3AIIISOd NAMONS SQOl Q3liddV 3Y 1 0 SOV0I...caesgi 30332 50S King Avenue Drxel University Clmu.Oi 30 Department of mechanical enginserieg prof essor Graham.?. Carey ClmuOi 30 and mechanics

PARTIAL REVISION: ABSORPTION SPECTRUM AND QUANTUM STATES OF THE PRASEODYMIUM ION. I. SINGLE CRYSTALS OF PRASEODYMIUM CHLORIDE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sayre, E.V.; Sancier, K.M.; Freed, S.

1958-07-01

In an analysis of term splitting in the absorption spectrum of 24 samples of praseodymium chloride, Judd (Proc. Roy. Soc. (London) A241, 414(1957)) found all but two of the authors' results to be constant with his. A discussion of reconciliation is presentrd, and the authors point out that the error is due to a mistake in descrimination between electronic transitions and the weak vibrationally coupled lines. (J.R.D.)

Risk factors for the development and severity of juvenile-onset recurrent respiratory papillomatosis: a systematic review.

PubMed

Niyibizi, Joseph; Rodier, Caroline; Wassef, Maggy; Trottier, Helen

2014-02-01

Juvenile-onset recurrent respiratory papillomatosis (JoRRP) is a rare yet aggressive disease caused by human papillomavirus (HPV). Although many newborns are likely exposed to HPV, few develop JoRRP and the clinical course of the disease varies from one child to another. This systematic review seeks to provide an up-to-date understanding of the risk factors for acquisition and severity. We conducted a comprehensive literature search in EMBASE, MEDLINE and EBMR databases using various combinations of keywords related to JoRRP etiology, risk factors and severity. We also searched Google Scholar and the reference lists of eligible studies. Our search was limited to original studies published in French or English between 1995 and July 2012 and to patients under 20 years of age. Of 1362 citations, we retrieved 102 articles and found 14 additional studies. We retained 32 studies meeting inclusion criteria. All were observational and together included 2296 JoRRP cases. Risk factors could be classified mainly as maternal and birth history, viral genotype, and host factors. A history of genital warts during pregnancy and delivery was strongly linked to the development of JoRRP. Depending on ethnicity, specific human leukocyte antigen class II alleles and immune response factors were important determinants of JoRRP acquisition and severity. HPV-11 genotype and younger age at onset of JoRRP were important predictors of severity. Genetic and immunological profiles underlying the acquisition and clinical course are not readily modifiable. Thus, preventing condylomas in women of childbearing age could reduce the burden of this life-threatening disease. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Dual color emitting Eu doped strontium orthosilicate phosphors synthesized by bio-template assisted ultrasound for solid state lightning and display applications.

PubMed

Venkataravanappa, M; Nagabhushana, H; Daruka Prasad, B; Darshan, G P; Basavaraj, R B; Vijayakumar, G R

2017-01-01

A novel Sr 2 SiO 4 :Eu (1-5mol %) superstructures (SS) were synthesized using bio-sacrificial A.V. gel assisted ultrasound method. Powder X-ray diffraction patterns confirmed the presence of both α and β phase formation. It was evident that the morphological growth was highly reliant on A.V. gel concentration, sonication time, pH and sonication power. The formation mechanisms for different hierarchical SS were proposed. From diffuse reflectance spectra, the energy band gap was estimated and found to be ∼4.70-5.11eV. The photoluminescence emission spectra for the excitation at 392nm, shows characteristic emission peaks at 593, 613, 654 and 702nm which were attributed to 5 D 0 → 7 F 0 , 7 F 1, 7 F 2 and 7 F 3 transitions of Eu 3+ ions respectively. Conversely, when the samples were subjected to the heat treatment at 850°C for 3h under argon atmosphere, display an intense broad emission peak with two de-convoluted peaks at 490 and 550nm due to 4f 6 5d 1 →4f 1 ( 8 S 7/2 ) transitions of Eu 2+ ions. The concentration quenching phenomenon was discussed which attributes to energy transfer, electron-phonon coupling and ion-ion interaction. The Judd-Ofelt intensity parameters and other radiative properties were estimated by using emission spectra. The CIE chromaticity coordinate values of Sr 2 SiO 4 :Eu 2+ and Eu 3+ nanophosphors were located in green and red regions respectively. The calculated CCT and CRI values specify that the present phosphor can be fairly useful for both green and red components of white LED's. Luminescence decay and quantum yield suggest the suitability of this phosphor as an efficient luminescent medium for light emitting diodes. Overall, the results elucidated a rapid, environmentally benign, cost-effective and convenient method for Sr 2 SiO 4 :Eu 3+ synthesis and for the possible applications such as solid state lighting and display devices. Copyright © 2016 Elsevier B.V. All rights reserved.

Structural and luminescence properties of samarium doped lead alumino borate glasses

NASA Astrophysics Data System (ADS)

Mohan, Shaweta; Kaur, Simranpreet; Singh, D. P.; Kaur, Puneet

2017-11-01

The study reports the effect of samarium concentration on the physical, structural and spectroscopic characteristics of samarium doped lead alumino borate glasses having composition 20PbO-(10-x)Al2O3-70B2O3-xSm2O3; x = 0.1, 0.5, 1.0 and 2.0 mol %. The glasses were fabricated by conventional melt-quenching technique and then characterized by XRD, FTIR, optical absorption and fluorescence spectra. X-ray diffraction studies confirmed the amorphous nature of the prepared glasses. FTIR spectra indicate the presence of BO3, BO4, AlO6 and a few other structural groups. Various physical properties such as density, molar volume, refractive index, rare earth ion concentration, boron-boron distance and polarizability etc. were determined using conventional methods and standard formulae. The Judd-Ofelt theory was applied on the optical absorption spectra of the glasses to evaluate the three phenomenological intensity parameters Ω2, Ω4 and Ω6. The value of Ω2 was found to be highest for glass with 1 mol% Sm2O3 and attributed to the asymmetry of the ligand field at the rare earth ion site and the rare earth oxygen (Sm-O) covalency. The calculated intensity parameters and fluorescence spectra were further used to predict the radiative transition probability (A), radiative lifetime (τR), branching ratio (βR), peak wavelength (λp), effective line widths (Δλeff) and stimulated emission cross-section (σ) for the characteristic 4G5/2 → 6H5/2, 6H7/2 and 6H9/2 transitions of the Sm3+ ion. Concentration quenching was observed for 2 mol% concentration of Sm2O3 and ascribed to energy transfer through various cross-relaxation channels between Sm3+ ions. Reasonably high values of branching ratios and stimulated emission cross-section for the prepared glasses points towards their utility in the development of visible lasers emitting in the reddish-orange spectral region. However, the glass with 1 mol% Sm2O3 was found to show better radiative properties.

New Radar Images of Asteroid 2014 JO25

NASA Image and Video Library

2017-05-09

This frame from a movie of asteroid 2014 JO25 was generated using radar data collected by NASA 230-foot-wide 70-meter Deep Space Network antenna at Goldstone, California on April 19, 2017. When the observations began 2014 JO25 was 1.53 million miles (2.47 million kilometers) from Earth. By the time the observations concluded, the asteroid was 1.61 million miles (2.59 million kilometers) away. The asteroid has a contact binary structure -- two lobes connected by a neck-like region. The largest of the asteroid's two lobes is estimated to be 2,000 feet (610 meters) across. Asteroid 2014 JO25 approached to within 1.1 million miles (1.8 million kilometers) of Earth on April 19. There are no future flybys by 2014 JO25 as close as this one for more than 400 years. The resolution of the radar images is about 25 feet (7.5 meters) per pixel. 154 images were used to create a movie. The movie can be seen at. https://photojournal.jpl.nasa.gov/catalog/PIA21597

Actinometric measurement of j(O3-O(1D)) using a luminol detector

NASA Technical Reports Server (NTRS)

Bairai, Solomon T.; Stedman, Donald H.

1992-01-01

The photolysis frequency of ozone to singlet D oxygen atoms has been measured by means of a chemical actinometer using a luminol based detector. The instrument measures j(O3-O(1D)) with a precision of 10 percent. The data collected in winter and spring of 1991 is in agreement with model predictions and previously measured values. Data from a global solar radiometer can be used to estimate the effects of local cloudiness on j(O3-O(1D)).

Radar Imagery of Asteroid 2014 JO25

NASA Image and Video Library

2017-04-19

This composite of 30 images of asteroid 2014 JO25 was generated with radar data collected using NASA Goldstone Solar System Radar in California Mojave Desert. https://photojournal.jpl.nasa.gov/catalog/PIA21594

1. JoAnn SieburgBaker, Photographer, September 1977. OVERALL VIEW OF ROUNDHOUSE. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. JoAnn Sieburg-Baker, Photographer, September 1977. OVERALL VIEW OF ROUNDHOUSE. - Southern Railway Company, Spencer Shops, Salisbury Avenue between Third and Eight Streets, Spencer, Rowan County, NC

10. JoAnn SieburgBaker, Photographer, September 1977. INTERIOR VIEW OF BACK ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. JoAnn Sieburg-Baker, Photographer, September 1977. INTERIOR VIEW OF BACK SHOP. - Southern Railway Company, Spencer Shops, Salisbury Avenue between Third and Eight Streets, Spencer, Rowan County, NC

Increased visfatin levels are associated with higher disease activity in anti-Jo-1-positive myositis patients.

PubMed

Hulejová, Hana; Kryštůfková, Olga; Mann, Heřman; Klein, Martin; Pavlíčková, Klára; Zámečník, Josef; Vencovský, Jiří; Šenolt, Ladislav

2016-01-01

The aim of this study was to evaluate serum levels of visfatin in anti-Jo-1-positive myositis patients, its expression in muscle tissue and to investigate potential relationships between visfatin, B-cell activating factor of the TNF family (BAFF), disease activity and anti-Jo-1 autoantibody levels. Serum levels of visfatin and BAFF were measured in 38 anti-Jo-1 positive myositis patients and 35 healthy subjects. Disease activity was evaluated by myositis disease activity assessment tool (MYOACT) using visual analogue scales (VAS) and by serum muscle enzymes. Visfatin expression was evaluated by immunohistochemistry in muscle tissue of myositis patients (n=10) and compared with non-inflammatory control muscle tissue samples from patients with myasthenia gravis (n=5). Serum visfatin and BAFF levels were significantly higher in myositis patients compared to healthy subjects and were associated with clinical muscle activity assessed by VAS. Only serum BAFF levels, but not visfatin levels, positively correlated with muscle enzyme concentrations and anti-Jo1 antibody levels. There was a positive correlation between visfatin and BAFF serum levels in myositis patients but a negative correlation was observed in healthy subjects. Visfatin expression was up-regulated in endomysial and perimysial inflammatory infiltrates of muscle tissue from myositis patients. Up-regulation of visfatin in myositis muscle tissue and an association between increased visfatin levels and muscle disease activity evaluated by MYOACT in anti-Jo-1 positive myositis patients could support possible role of visfatin in the pathogenesis of myositis.

3. JoAnn SieburgBaker, Photographer, September 1977. VIEW OF BACK SHOP ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. JoAnn Sieburg-Baker, Photographer, September 1977. VIEW OF BACK SHOP FROM SOUTHEAST. - Southern Railway Company, Spencer Shops, Salisbury Avenue between Third and Eight Streets, Spencer, Rowan County, NC

5. JoAnn SieburgBaker, Photographer, September 1977. VIEW OF ICE HOUSE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. JoAnn Sieburg-Baker, Photographer, September 1977. VIEW OF ICE HOUSE AND SURROUNDING BUILDINGS. - Southern Railway Company, Spencer Shops, Salisbury Avenue between Third and Eight Streets, Spencer, Rowan County, NC

7. JoAnn SieburgBaker, Photographer, September 1977. VIEW OF OFFICES IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. JoAnn Sieburg-Baker, Photographer, September 1977. VIEW OF OFFICES IN BACK SHOP. - Southern Railway Company, Spencer Shops, Salisbury Avenue between Third and Eight Streets, Spencer, Rowan County, NC

Fermilab | LBNF | Home

Science.gov Websites

million to LBNF/DUNE in first-ever umbrella science agreement with U.S. Jo Johnson (UK Minister of State Minister of State for Universities, Science, Research and Innovation Jo Johnson signed the U.S.-UK Science

4. JoAnn SieburgBaker, Photographer, September 1977. OVERALL VIEW OF BACK ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. JoAnn Sieburg-Baker, Photographer, September 1977. OVERALL VIEW OF BACK SHOP FROM ROOF OF ROUNDHOUSE. - Southern Railway Company, Spencer Shops, Salisbury Avenue between Third and Eight Streets, Spencer, Rowan County, NC

Secreted histidyl-tRNA synthetase splice variants elaborate major epitopes for autoantibodies in inflammatory myositis.

PubMed

Zhou, Jie J; Wang, Feng; Xu, Zhiwen; Lo, Wing-Sze; Lau, Ching-Fun; Chiang, Kyle P; Nangle, Leslie A; Ashlock, Melissa A; Mendlein, John D; Yang, Xiang-Lei; Zhang, Mingjie; Schimmel, Paul

2014-07-11

Inflammatory and debilitating myositis and interstitial lung disease are commonly associated with autoantibodies (anti-Jo-1 antibodies) to cytoplasmic histidyl-tRNA synthetase (HisRS). Anti-Jo-1 antibodies from different disease-afflicted patients react mostly with spatially separated epitopes in the three-dimensional structure of human HisRS. We noted that two HisRS splice variants (SVs) include these spatially separated regions, but each SV lacks the HisRS catalytic domain. Despite the large deletions, the two SVs cross-react with a substantial population of anti-Jo-l antibodies from myositis patients. Moreover, expression of at least one of the SVs is up-regulated in dermatomyositis patients, and cell-based experiments show that both SVs and HisRS can be secreted. We suggest that, in patients with inflammatory myositis, anti-Jo-1 antibodies may have extracellular activity. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

GASP. II. A MUSE View of Extreme Ram-Pressure Stripping along the Line of Sight: Kinematics of the Jellyfish Galaxy JO201

NASA Astrophysics Data System (ADS)

Bellhouse, C.; Jaffé, Y. L.; Hau, G. K. T.; McGee, S. L.; Poggianti, B. M.; Moretti, A.; Gullieuszik, M.; Bettoni, D.; Fasano, G.; D'Onofrio, M.; Fritz, J.; Omizzolo, A.; Sheen, Y.-K.; Vulcani, B.

2017-07-01

This paper presents a spatially resolved kinematic study of the jellyfish galaxy JO201, one of the most spectacular cases of ram-pressure stripping (RPS) in the GAs Stripping Phenomena in galaxies with MUSE (GASP) survey. By studying the environment of JO201, we find that it is moving through the dense intracluster medium of Abell 85 at supersonic speeds along our line of sight, and that it is likely accompanied by a small group of galaxies. Given the density of the intracluster medium and the galaxy’s mass, projected position, and velocity within the cluster, we estimate that JO201 must so far have lost ˜50% of its gas during infall via RPS. The MUSE data indeed reveal a smooth stellar disk accompanied by large projected tails of ionized ({{H}}α ) gas, composed of kinematically cold (velocity dispersion <40 km s-1) star-forming knots and very warm (>100 km s-1) diffuse emission, that extend out to at least ˜ 50 {kpc} from the galaxy center. The ionized {{H}}α -emitting gas in the disk rotates with the stars out to ˜6 kpc but, in the disk outskirts, it becomes increasingly redshifted with respect to the (undisturbed) stellar disk. The observed disturbances are consistent with the presence of gas trailing behind the stellar component resulting from intense face-on RPS along the line of sight. Our kinematic analysis is consistent with the estimated fraction of lost gas and reveals that stripping of the disk happens outside-in, causing shock heating and gas compression in the stripped tails.

Content Analysis of the 20 Most Influential Articles in "PIQ"

ERIC Educational Resources Information Center

Cho, Yonjoo; Park, Sunyoung

2012-01-01

The purpose of this study is to examine key research themes in human performance technology (HPT) through content analysis of the 20 most influential articles identified in Cho, Jo, Park, Kang, and Chen (2011). Three questions guiding this inquiry are: (1) What are the key themes of the 20 most influential articles in "PIQ", (2) What information…

Evaluation of jojoba oil as a low-energy fat. 1. A 4-week feeding study in rats.

PubMed

Verschuren, P M

1989-01-01

The nutritional properties of jojoba oil (JO) were examined in a 4-wk feeding study of rats fed a diet with JO at dose levels of 2.2, 4.5 and 9%, supplemented with a conventional fat up to 18%. General health, survival and food intake were not adversely affected. Body-weight gains showed a dose-related decline, which amounted to 20% of the body weight in the high-dose group of both sexes. Clinical chemistry revealed significantly increased levels of various enzymes that were indicative of cell damage. Haematology showed a dose-related increase in white blood cells. On necropsy an apparent distension of the small intestine was found. Histopathological evaluation revealed marked intestinal changes characterized by massive vacuolization and lipid deposition in the enterocytes, accompanied by distension of the villi and an increased cell turnover of small intestinal cells. Faeces production and faeces lipid content were increased with increasing JO levels. The recovery of JO in the faeces also increased in a dose-related manner and was found to be correlated with the intestinal histopathological changes. The significant adverse clinical and histopathological effects observed in this study imply that JO cannot be considered as a promising alternative dietary fat with a low digestibility.

2. JoAnn SieburgBaker, Photographer, September 1977. SECTION SHOWING BACK OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. JoAnn Sieburg-Baker, Photographer, September 1977. SECTION SHOWING BACK OF ROUNDHOUSE AND END OF BACK SHOP WHERE CRANE WAS LOCATED. - Southern Railway Company, Spencer Shops, Salisbury Avenue between Third and Eight Streets, Spencer, Rowan County, NC

Functional outcome and prognostic factors in anti-Jo1 patients with antisynthetase syndrome

PubMed Central

2013-01-01

Introduction The aims of this present study were firstly to assess the outcome, including functional course, in anti-Jo1 positive patients with antisynthetase syndrome (ASS), and secondly to determine predictive parameters of poor outcome in these patients. Methods The medical records of 86 consecutive anti-Jo1 patients with ASS were reviewed in 4 academic centers. Results 13 patients (15.1%) achieved remission of ASS, whereas 55 (63.9%) improved and 18 (20.9%) deteriorated in their clinical status. Both steroid and cytotoxic drugs could be discontinued in only 4.7% of patients. ASS was associated with decreased quality of life at long-term follow-up: only 69.2% of patients considered to be in remission experienced a return to previous normal activities; and 24.7% of other patients with non-remitting ASS still had a marked reduction of activities (as shown by the disability scale of the Health Assessment Questionnaire). Decreased quality of life was further due to calcinosis cutis (8.1%) and adverse effects of steroid therapy (36%). Factors associated with ASS deterioration were older age, pulmonary and esophageal involvement, calcinosis cutis and cancer. Higher anti-Jo1 levels were further associated with disease severity in ASS patients. Conclusions The present study shows high morbidity related to ASS. Furthermore, we suggest that patients with predictive factors of ASS deterioration may require more aggressive therapy. Our findings also suggest that in anti-Jo1 patients with severe esophageal manifestations, combined high dose steroids and intravenous immunoglobulins might be proposed as the first line therapy. Finally, as cancer occurred in 14% of anti-Jo1 patients, our findings underscore that the search for cancer should be performed in these patients. PMID:24286268

Functional outcome and prognostic factors in anti-Jo1 patients with antisynthetase syndrome.

PubMed

Marie, Isabelle; Hatron, Pierre-Yves; Cherin, Patrick; Hachulla, Eric; Diot, Elisabeth; Vittecoq, Olivier; Menard, Jean-François; Jouen, Fabienne; Dominique, Stéphane

2013-10-08

The aims of this present study were firstly to assess the outcome, including functional course, in anti-Jo1 positive patients with antisynthetase syndrome (ASS), and secondly to determine predictive parameters of poor outcome in these patients. The medical records of 86 consecutive anti-Jo1 patients with ASS were reviewed in 4 academic centers. 13 patients (15.1%) achieved remission of ASS, whereas 55 (63.9%) improved and 18 (20.9%) deteriorated in their clinical status. Both steroid and cytotoxic drugs could be discontinued in only 4.7% of patients. ASS was associated with decreased quality of life at long-term follow-up: only 69.2% of patients considered to be in remission experienced a return to previous normal activities; and 24.7% of other patients with non-remitting ASS still had a marked reduction of activities (as shown by the disability scale of the Health Assessment Questionnaire). Decreased quality of life was further due to calcinosis cutis (8.1%) and adverse effects of steroid therapy (36%). Factors associated with ASS deterioration were older age, pulmonary and esophageal involvement, calcinosis cutis and cancer. Higher anti-Jo1 levels were further associated with disease severity in ASS patients. The present study shows high morbidity related to ASS. Furthermore, we suggest that patients with predictive factors of ASS deterioration may require more aggressive therapy. Our findings also suggest that in anti-Jo1 patients with severe esophageal manifestations, combined high dose steroids and intravenous immunoglobulins might be proposed as the first line therapy. Finally, as cancer occurred in 14% of anti-Jo1 patients, our findings underscore that the search for cancer should be performed in these patients.

Teaching with Technology. Software That's Right for You.

ERIC Educational Resources Information Center

Allen, Denise

1995-01-01

Recommends software to help teachers plan curriculum in the areas of comprehensive language arts ("Cornerstone"); writing and information ("Keroppi Day Hopper"); creative writing and imagination ("Imagination Express"); reading ("Jo-Jo's Reading Circus"); math ("Careers in Math: From Architects to Astronauts") and nature ("Eyewitness"). Provides…

A contribution to regional stratigraphic correlations of the Afro-Brazilian depression - The Dom João Stage (Brotas Group and equivalent units - Late Jurassic) in Northeastern Brazilian sedimentary basins

NASA Astrophysics Data System (ADS)

Kuchle, Juliano; Scherer, Claiton Marlon dos Santos; Born, Christian Correa; Alvarenga, Renata dos Santos; Adegas, Felipe

2011-04-01

The Dom João Stage comprises an interval with variable thickness between 100 and 1200 m, composed of fluvial, eolian and lacustrine deposits of Late Jurassic age, based mainly on the lacustrine ostracod fauna (although the top deposits may extend into the Early Cretaceous). These deposits comprise the so-called Afro-Brazilian Depression, initially characterized as containing the Brotas Group of the Recôncavo Basin (which includes the Aliança and the Sergi Formations) and subsequently extended into the Tucano, Jatobá, Camamu, Almada, Sergipe, Alagoas and Araripe Basins in northeastern Brazil, encompassing the study area of this paper. The large occurrence area of the Dom João Stage gives rise to discussions about the depositional connectivity between the basins, and the real extension of sedimentation. In the first studies of this stratigraphic interval, the Dom João Stage was strictly associated with the rift phase, as an initial stage (decades of 1960-70), but subsequent analyses considered the Dom João as an intracratonic basin or pre-rift phase - without any relation to the active mechanics of a tectonic syn-rift phase (decades of 1980-2000). The present work developed an evolutionary stratigraphic and tectonic model, based on the characterization of depositional sequences, internal flooding surfaces, depositional systems arrangement and paleoflow directions. Several outcrops on the onshore basins were used to build composite sections of each basin, comprising facies, architectural elements, depositional systems, stratigraphic and lithostratigraphic frameworks, and paleocurrents. In addition to that, over a hundred onshore and offshore exploration wells were used (only 21 of which are showed) to map the depositional sequences and generate correlation sections. These show the characteristics and relations of the Dom João Stage in each studied basin, and they were also extended to the Gabon Basin. The results indicate that there were two main phases during the Dom João Stage, in which distinctive sedimentary environments were developed, reflecting depositional system arrangements, paleoflow directions were diverse, and continuous or compartmented basins were developed.

The asteroid 2014 JO25

NASA Astrophysics Data System (ADS)

Vodniza, Alberto; Pereira, Mario

2017-10-01

The asteroid 2014 JO25 was discovered by A. D. Grauer at the Mt. Lemmon Survey on May 2014, and Joe Masiero used observations from the NEOWISE in 2014 to estimate a diameter of 650 meters [1]. However, using the radio telescope at Arecibo-Puerto Rico, astronomers obtained radar images on April 17-2017 and Edgar Rivera Valentín (scientist at Arecibo) said: “We found 2014 JO25 is a contact binary asteroid, two space rocks that were originally separate bodies, and each segment is about 640 meters and 670 meters, for a total of about 1.3 km long. Its rotation is of 3.5 hours” [2]. This asteroid flew past Earth on April 19 at a distance of about 4.6 lunar distances from the Earth. This was the closest approach by an asteroid since 4179 Toutatis. Toutatis flew past Earth on September 2004 at a distance of about 4 lunar distances from the Earth [3]. In April 12-2020 the asteroid will be at a minimum possible distance of 0.1617280 A.U from Earth [4]. From our observatory, located in Pasto-Colombia, we obtained a lot of pictures. Our data was published by the Minor Planet Center [5] and also appears at the web page of NEODyS [6]. Astrometry and photometry were carried out, and we calculated the orbital elements. We obtained the following orbital parameters: eccentricity=0.88454+/-0.00152, semi-major axis= 2.0573+/- 0.0216 A.U, orbital inclination=25.22+/-0.10 deg, longitude of the ascending node =30.6530+/-0.0032 deg, argument of perihelion=49.586+/-0.012 deg, mean motion = 0.33402+/-0.00527 deg/d, perihelion distance=0.237524+/-0.000644 A.U, aphelion distance=3.8770+/-0.0449 A.U, absolute magnitude =18.1. The parameters were calculated based on 164 observations. Dates: 2017 April: 22 to 24 with mean residual=0.22 arcseconds.The asteroid has an orbital period of 2.95 years.[1] https://echo.jpl.nasa.gov/asteroids/2014JO25/2014JO25_planning.html[2] http://earthsky.org/astronomy-essentials/large-asteroid-2014-jo25-close-april-19-2017-how-to-see[3] https://cneos.jpl.nasa.gov/news/news196.html[4] http://newton.dm.unipi.it/neodys/index.php?pc=1.1.8&n=2014JO25[5] http://www.minorplanetcenter.net/db_search/show_object?utf8=%E2%9C%93&object_id=2014+JO25[6] http://newton.dm.unipi.it/neodys/index.php?pc=2.1.2&o=H78&ab=8

Photoluminescence studies of high-efficient red-emitting K{sub 2}Y(WO{sub 4})(PO{sub 4}):Eu{sup 3+} phosphor for NUV LED

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xinguo; State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275; Chen, Mengyang

Highlights: • Novel K{sub 2}Y(WO{sub 4})(PO{sub 4}):Eu{sup 3+} red phosphors were prepared by solid-state method. • Phosphors exhibit strong red light under NUV excitation with quantum efficiency of 70.5 %. • Judd–Ofelt analysis ascertains the presence of Eu{sup 3+} in a highly asymmetric environment. • The red LED prototype was fabricated with KYWP:Eu{sup 3+} phosphor and InGaN chip. - Abstract: A series of high-efficient red-emitting phosphors K{sub 2}Y(WO{sub 4})(PO{sub 4}):Eu{sup 3+} have been successfully synthesized by conventional solid-state reaction, and its photoluminescence (PL) properties have been investigated. The phosphors can be excited efficiently by NUV light, then exhibit strong redmore » emission with quantum efficiency of 70.5%. The concentration quenching takes place at relatively high concentration of Eu{sup 3+} (x = 0.70), which is further confirmed by the variation of decay curves of the entitled phosphors. Judd–Ofelt analysis ascertains the presence of Eu{sup 3+} in a highly asymmetric environment. The phosphor exhibits good thermal stability (92.5% at 100 °C and 84.1% at 180 °C). The red LED prototype fabricated by opyimized-composition K{sub 2}Y(WO{sub 4})(PO{sub 4}):0.70Eu{sup 3+} phosphor and 395 nm-emitting InGaN chips exhibit bright red emission. The results indicate that the K{sub 2}Y(WO{sub 4})(PO{sub 4}):Eu{sup 3+} phosphors are promising red phosphors for NUV LED.« less

DEAN: A Program for Dynamic Engine Analysis.

DTIC Science & Technology

1985-01-01

hardware and memory limitations. DIGTEM (ref. 4), a recently written code allows steady-state as well as transient calculations to be performed. DIGTEM has...Computer Program for Generating Dynamic Turbofan Engine Models ( DIGTEM )," NASA TM-83446. 5. Carnahan, B., Luther, H.A., and Wilkes, J.O., Applied Numerical

Leadership, Longevity, and Leaning In: An Interview With Mary Jo (Joey) Bulfin.

PubMed

Prestia, Angela S

2018-06-01

This column profiles Mary Jo Bulfin, MBA, RN, CENP, chief executive officer of St. Mary's Medical Center, West Palm Beach, Florida. Ms Bulfin began her career as a staff nurse in the organization where she is now the CEO and discusses her career path and lessons learned.

Minimalism. Clip and Save.

ERIC Educational Resources Information Center

Hubbard, Guy

2002-01-01

Provides background information on the art movement called "Minimalism" discussing why it started and its characteristics. Includes learning activities and information on the artist, Donald Judd. Includes a reproduction of one of his art works and discusses its content. (CMK)

Spectroscopic and laser properties of Er{sup 3+} doped fluoro-phosphate glasses as promising candidates for broadband optical fiber lasers and amplifiers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Babu, S.; Seshadri, M.; Reddy Prasad, V.

2015-10-15

Highlights: • Erbium doped different fluoro-phosphate glasses are prepared and characterized. • Spectroscopic properties have been determined using Judd–Ofelt and Mc-Cumber theory. • Prominent laser transition Er{sup 3+}:{sup 4}I{sub 13/2} → {sup 4}I{sub 15/2} is observed at 1.53 μm. - Abstract: Different fluoro-phosphate glasses doped with 0.5 mol% Er{sup 3+} doped are prepared by melt quenching method. Both structural and spectroscopic properties have been characterized in order to evaluate their potential as both laser source and amplifier materials. Optical absorption measurements are carried out and analyzed through Judd–Ofelt and Mc-Cumber theories where spectroscopic parameters such as intensity parameters Ω{sub l}more » (λ = 2,4,6), transition probabilities, radiative lifetimes, stimulated absorption cross-sections and emission cross-sections at 1.5 μm have been evaluated for Er{sup 3+} doped different fluorophosphate glasses. The various luminescence and gain properties are explained from photoluminescence studies. The decay curve analysis have been done for obtaining the decay time constants of Er{sup 3+} excited level {sup 4}I{sub 13/2} in all the fluoro-phosphate glasses. The obtained results of each glass matrix are compared with the equivalent parameters for several other host glasses. These fluoro-phosphate glasses are found to be suitable candidates for laser and amplifier applications.« less

ELISA subtypization of anti-ENA autoantibodies in clinical management of autoimmune diseases in Bosnia and Herzegovina.

PubMed

Subasic, Djemo; Karamehic, Jasenko; Gavrankapetanovic, Faris; Hodzic, Harun; Kasumovic, Mersija; Delic-Sarac, Marina; Prljaca-Zecevic, Lamija

2009-01-01

The basis of autoimmune diseases such as SLE (Systemic Lupus Eritematodes), Sjogren's syndrome, scleroderma, dermatomyositis and polymiositis is the creation of auto-antibodies to the following specific extractable nuclear antigens (ENA):Jo-1, Ssl-70, SS-A, SS-B, Sm and Sm/RNPs. Some of these antigens are in fact enzymes (Jo-1-histidil-tRNA synthetase, Scl-70-topoisomerase) which are inhibited by specific autoantibodies--this leads to disturbance in the metabolism of DNA and protein biosynthesis. During 2009, we analyzed total of 87 serum samples of patients suspected for autoimmune disorder using ANA-IFA and ELISA-ENA-6 methods. After establishing IFA-ANA positivity (83.9%), all serum specimens; ANA positive and negative, were subtypized by ELISA ENA-6 test. Analysis showed the highest incidence of anti-SS-A (56%), and incidence of anti-SS-B (29.8%), anti-Sm/ RNP (11.5%), anti-Jo-1 (2.3%) and anti-Scl-70 (1,1%) auto-antibodies. Also, 78.5% of IFA-ANA negative serum specimens showed high level of positivity (212.50 and 277.0 IU/ml) to SS-A (78.5%) and SS-B (21.4%) antigenes using ELISA-ENA-6 subtypization. Following these results, we conclude that it is necessary to introduce Western blot confirmation testing. After comparing with other clinical findings, we diagnosed the following autoimmune diseases: SLE, Sjogren's syndrome and dermatomiosytis.

Targeting Stat3 With G-Quartet Oligonucleotides in Metastatic Prostate Cancer

DTIC Science & Technology

2005-04-01

Wegenka UM, Lutticken C, Buschmann J, et al. The interleukin-6-activated acute- 34. Mazurmder A, Neamati N, Ojwang JO, Sunder S, Rando RF, Pommier Y...Chem 1995; 270: 1754-60. antisense directed against telomerase RNA. Oncogene 1998; 16: [8] Mazumder A, Neamati N, Ojwang JO, Sunder S, Rando RF, 3323

Autoantibody levels in myositis patients correlate with clinical response during B cell depletion with rituximab.

PubMed

Aggarwal, Rohit; Oddis, Chester V; Goudeau, Danielle; Koontz, Diane; Qi, Zengbiao; Reed, Ann M; Ascherman, Dana P; Levesque, Marc C

2016-06-01

To determine the longitudinal trends in serum levels of four myositis-associated autoantibodies: anti-Jo-1, -transcription intermediary factor 1 γ (TIF1-γ), -signal recognition particle (SRP) and -Mi-2, after B cell depletion with rituximab, and to determine the longitudinal association of these autoantibody levels with disease activity as measured by myositis core-set measures (CSMs). Treatment-resistant adult and pediatric myositis subjects (n = 200) received rituximab in the 44-week Rituximab in Myositis Trial. CSMs [muscle enzymes, manual muscle testing (MMT), physician and patient global disease activity, HAQ, and extramuscular disease activity] were evaluated monthly and anti-Jo-1 (n = 28), -TIF1-γ (n = 23), -SRP (n = 25) and -Mi-2 (n = 26) serum levels were measured using validated quantitative ELISAs. Temporal trends and the longitudinal relationship between myositis-associated autoantibodies levels and CSM were estimated using linear mixed models. Following rituximab, anti-Jo-1 levels decreased over time (P < 0.001) and strongly correlated with all CSMs (P < 0.008). Anti-TIF1-γ levels also decreased over time (P < 0.001) and were only associated with HAQ, MMT and physician and patient global disease activity. Anti-SRP levels did not change significantly over time, but were significantly associated with serum muscle enzymes. Anti-Mi-2 levels significantly decreased over time and were associated with muscle enzymes, MMT and the physician global score. Anti-Jo-1, anti-TIF1-γ and anti-Mi-2 levels in myositis subjects decreased after B cell depletion and were correlated with changes in disease activity, whereas anti-SRP levels were only associated with longitudinal muscle enzyme levels. The strong association of anti-Jo-1 levels with clinical outcomes suggests that anti-Jo-1 autoantibodies may be a good biomarker for disease activity. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Distinct sensory representations of wind and near-field sound in the Drosophila brain

PubMed Central

Yorozu, Suzuko; Wong, Allan; Fischer, Brian J.; Dankert, Heiko; Kernan, Maurice J.; Kamikouchi, Azusa; Ito, Kei; Anderson, David J.

2009-01-01

Behavioral responses to wind are thought to play a critical role in controlling the dispersal and population genetics of wild Drosophila species1,2, as well as their navigation in flight3, but their underlying neurobiological basis is unknown. We show that Drosophila melanogaster, like wild-caught Drosophila strains4, exhibits robust wind-induced suppression of locomotion (WISL), in response to air currents delivered at speeds normally encountered in nature1,2. Here we identify wind-sensitive neurons in Johnston’s Organ (JO), an antennal mechanosensory structure previously implicated in near-field sound detection (reviewed in5,6). Using Gal4 lines targeted to different subsets of JO neurons7, and a genetically encoded calcium indicator8, we show that wind and near-field sound (courtship song) activate distinct populations of JO neurons, which project to different regions of the antennal and mechanosensory motor center (AMMC) in the central brain. Selective genetic ablation of wind-sensitive JO neurons in the antenna abolishes WISL behavior, without impairing hearing. Different neuronal subsets within the wind-sensitive population, moreover, respond to different directions of arista deflection caused by airflow and project to different regions of the AMMC, providing a rudimentary map of wind-direction in the brain. Importantly, sound- and wind-sensitive JO neurons exhibit different intrinsic response properties: the former are phasically activated by small, bi-directional, displacements of the aristae, while the latter are tonically activated by unidirectional, static deflections of larger magnitude. These different intrinsic properties are well suited to the detection of oscillatory pulses of near-field sound and laminar airflow, respectively. These data identify wind-sensitive neurons in JO, a structure that has been primarily associated with hearing, and reveal how the brain can distinguish different types of air particle movements, using a common sensory organ. PMID:19279637

Distribution of elements in the Salt Wash member of the Morrison Formation in the Jo Dandy area, Montrose County, Colorado

USGS Publications Warehouse

Newman, William L.; Elston, Donald P.

1957-01-01

A study of the distribution of elements in the Salt Wash member of the Morrison formation of Jurassic age from samples taken in the Jo Dandy area, Montrose County, Colo., was made to determine average chemical composition of mudstone and sandstone and to determine the magnitude of variations in concentrations of elements within similar rock types. Analytical data were obtained by semiquantitative spectrographic and radiometric methods. Results of the study show that variations in concentrations of about 20 elements commonly detected by semiquantititive spectrographic analyses of sedimentary rocks are small for a specific rock type; therefore, considerable confidence may be placed upon the average chemical appears to be no significant relation between chemical composition of mudstone or sandstone and distance from known uranium-vanadium ore or mineralization rock. Mudstone generally contains greater concentrations of the elements studied than sandstone. The chemical composition of red mudstone is similar to the chemical composition of green mudstone except that red mudstone was found to contain almost twice as much calcium as green mudstone in the Jo Dandy area. Samples of the unoxidized sandstone from the Jo Dandy area contain about twice as much calcium, three times as much strontium, but only about one-half as much as zirconium as oxidized sandstone; except for these elements the chemical compositions of both categories of sandstone are similar. Samples of sandstone of the Salt Wash member in the Jo Dandy area contain more potassium, magnesium, vanadium, and nickel than “average sandstone” of the Salt Wash member. The distribution of bismuth in rocks of the Jo Dandy area suggests that bismuth and perhaps part of the potassium and magnesium found in rocks of the Salk Wash member were either derived from solutions which ascended from the underlying salt- and gypsum-bearing Paradox member that was incorporated with rocks of the Salt Wash during sedimentation.

Spinning New Tales from Traditional Texts: Donna Jo Napoli and the Rewriting of Fairy Tale.

ERIC Educational Resources Information Center

Crew, Hilary S.

2002-01-01

Demonstrates how Donna Jo Napoli changes generic conventions and reworks discursive formations in order to retell tradition tales. Discusses the narrative strategies she uses in telling her stories, her representation of male and female characters in regard to gender and gendered relationships, and the way she renegotiates ideologies and value…

Thrilling but Pointless: General JO Shelby’s 1863 Cavalry Raid

DTIC Science & Technology

2013-12-13

painfully acute. The air seems filled with exquisite music ; cities and towns rise up on every hand, crowned with spires and radiant with ten thousand...Raid. By the end of festivities , at nearly 2 a.m., Captain Hart recited a prepared poem entitled “Jo Shelby’s Raid.” The spirit of Shelby’s Brigade

Viscous Interactions at Hypersonic Speed.

DTIC Science & Technology

1986-09-12

had been allowed to occur. The experimental transition Reynolds numbers apd a lesser effect for high studies of Morrisette Stone and Carey l 0 at... joJO lSR TO ~tAS. 2 I(h% LOU -m Fir26 Meet Traner Distribution to theSo Cone in ’sens Asymmnesr T eaedtlond Flow Induced byTwo Mjeoet GOMM in the

77 FR 59183 - Jo-Carroll Energy, Inc.; Notice of Application

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-26

... Energy, Inc.; Notice of Application Take notice that on September 12, 2012, Jo-Carroll Energy, Inc. (NFP... application pursuant to section 7(f) of the Natural Gas Act (NGA), as amended, requesting to amend its present... forth in the application, which is on file with the Commission and open to the public for inspection...

Characterisation of J(O1D) at Cape Grim 2000-2005

NASA Astrophysics Data System (ADS)

Wilson, S. R.

2014-07-01

Estimates of the rate of production of excited oxygen atoms due to the photolysis of ozone J(O1D) have been derived from radiation measurements carried out at Cape Grim, Tasmania (40.6° S, 144.7° E). These estimates agree well with measurements made during SOAPEX-II and with model estimates of clear sky photolysis rates. Observations spanning 2000-2005 have been used to quantify the impact of season, cloud and ozone column amount. The annual cycle of J(O1D) has been investigated via monthly means. These means show an inter-annual variation (monthly standard deviation) of 9%, but in midsummer and midwinter this reduces to 3-4%. Factors dependent upon solar zenith angle and satellite derived total ozone column explain 87% of the observed signal variation of the individual measurements. The impact of total column ozone, expressed as a Radiation Amplification Factor (RAF), is found to be ~1.45, in agreement with model estimates. This ozone dependence explains 20% of the variation observed at medium solar zenith angles (30-50°). The impact of clouds results in a median reduction of 14% in J(O1D) for the same solar zenith angle range. At all solar zenith angles less than 50° approximately 10% of measurements show enhanced J(O1D) due to cloud scattering and this fraction climbs to 25% at higher solar angles. Including estimates of cloudiness derived from Long Wave Radiation measurements resulted in a statistically significant fit to observations but the quality of the fit did not increase significantly as measured by the reduced R2.

Enhancing Coping and Supporting Protective Factors after a Disaster: Findings From a Quasi-Experimental Study

ERIC Educational Resources Information Center

Powell, Tara; Thompson, Sanna J.

2016-01-01

Objective: This article presents the Journey of Hope (JoH), a school-based intervention for children who have experienced a collective trauma such as a natural disaster. Through the use of group work, the JoH focuses on building coping skills and enhancing protective factors to help children recover. Method: This quasi-experimental research…

A Call to Action: JoBeth Allen, NCTE's 2012 Outstanding Educator in the Language Arts

ERIC Educational Resources Information Center

Tisdale, Carmen

2012-01-01

This article is a tribute to JoBeth Allen, recipient of the Elementary Section's 2012 award for Outstanding Educator in the English Language Arts. Each year, this award recognizes a distinguished educator who has made major contributions to the field of language arts in elementary education. This article was written by second-grade teacher and…

The Secret to Patron-Centered Web Design: Cheap, Easy, and Powerful Usability Techniques

ERIC Educational Resources Information Center

Reynolds, Erica

2008-01-01

When the Johnson County Library (JoCo Library), a midsize suburban public library in Kansas City, Kansas, completely rebuilt its 2,000-plus-page website--one that had remained relatively stable for almost 5 years--the reaction from patrons and staff members was overwhelmingly positive. The web development team at the JoCo Library realized that the…

Jo Ann Rinaudo, PhD | Division of Cancer Prevention

Cancer.gov

Dr. Jo Ann Rinaudo is a Program Director in the Cancer Biomarkers Research Group in the Division of Cancer Prevention at the National Cancer Institute. She received a doctoral degree from the University of Toronto, where she studied chemical carcinogenesis in the liver. She was in the pathology department and has a broad background in human disease. Post-graduate training

Establishment and Characterization of a Highly Tumourigenic and Cancer Stem Cell Enriched Pancreatic Cancer Cell Line as a Well Defined Model System

PubMed Central

Fredebohm, Johannes; Boettcher, Michael; Eisen, Christian; Gaida, Matthias M.; Heller, Anette; Keleg, Shereen; Tost, Jörg; Greulich-Bode, Karin M.; Hotz-Wagenblatt, Agnes; Lathrop, Mark; Giese, Nathalia A.; Hoheisel, Jörg D.

2012-01-01

Standard cancer cell lines do not model the intratumoural heterogeneity situation sufficiently. Clonal selection leads to a homogeneous population of cells by genetic drift. Heterogeneity of tumour cells, however, is particularly critical for therapeutically relevant studies, since it is a prerequisite for acquiring drug resistance and reoccurrence of tumours. Here, we report the isolation of a highly tumourigenic primary pancreatic cancer cell line, called JoPaca-1 and its detailed characterization at multiple levels. Implantation of as few as 100 JoPaca-1 cells into immunodeficient mice gave rise to tumours that were histologically very similar to the primary tumour. The high heterogeneity of JoPaca-1 was reflected by diverse cell morphology and a substantial number of chromosomal aberrations. Comparative whole-genome sequencing of JoPaca-1 and BxPC-3 revealed mutations in genes frequently altered in pancreatic cancer. Exceptionally high expression of cancer stem cell markers and a high clonogenic potential in vitro and in vivo was observed. All of these attributes make this cell line an extremely valuable model to study the biology of and pharmaceutical effects on pancreatic cancer. PMID:23152778

Propagation of Polarization Modulated Beams Through a Turbulent Atmosphere

DTIC Science & Technology

2014-11-24

Clifford Algebra to Geometric Calculus , Reidel, 1984. Hirschfelder, J.O., Curtiss, C.F. & Bird, R.B., Molecular Theory of Gases and Liquids, Wiley, 1954...are made explicit in a Poincaré sphere and geometric (Clifford) algebra representation. Section 5.0 of this report provides the evidence supporting...MEDIA 4.0 LABORATORY TEST CONFIGURATIONS 5.0 TEST RESULTS 5.1 DATA ANALYSIS METHODS 5.2 DATA ANALYSIS 6.0 GEOMETRIC ALGEBRA 6.1 INTRODUCTION

Imbalanced Diet Deficient in Calcium and Vitamin D- Induced Juvenile Osteopenia in Rats; the Potential Therapeutic Effect of Egyptian Moghat Roots Water Extract (Glossostemon bruguieri).

PubMed

Ghareeb, Doaa A; El-Rashidy, Fatma H; El-Mallawany, Sherif

2014-01-01

This study aimed to explore and validate a new juvenile osteopenic (JO) rat model then examine the efficacy of moghat (Glossostemon bruguieri) as an alternative reversal therapy for JO. Phytochemical screening analysis showed that moghat contains 5.8% alkaloids, 1.5% flavonoids and 13.2% total phenols. Juvenile osteopenia was induced in 15 days old Sprague- Dawley female rats by feeding them free Ca and vitamin D synthetic diet for 21 days. Osteopenic rats were either treated with moghat (0.8 g dried plant tissue/Kg body weight, orally), or with a reference nutritional supplements of calcium chloride (14 mg Ca/Kg) and vitamin D3 (7 IU/Kg), for extra 21 days. Both untreated and treated groups were compared to a control group that fed a regular pelleted food. Our results showed that osteopenic rats lost normal bone tissue architecture, 30 % of body mass, 54 % of bone mass and finally 93% of bone calcium mass. Furthermore, these rats showed a markedly increase in serum phosphate, PTH, alkaline phosphatase, aspartate transaminase activities and creatinine level as compared to the control group. Moghat administration was successfully reversed osteopenia by normalizing body and bone masses to the reference ranges, increased the bone calcium mass by 17 fold without any detectable side effects on liver and kidney physiological performance. Therefore, moghat could be considered as potent safe -JO- reversal extract.

Precision Strike Technology Symposium (PSTS 09)

DTIC Science & Technology

2009-10-29

Control System) AUR (All-Up-Round) UHF SATCOM GPS JIC Threat and Target Data NGA Mapping, Charting & Geodesy 5 0 IRAQ SAU DI AR ABIA OM AN EM IRA TES JO...d M il it ary Ci ty Abu Dhabi qom Ahraz Shiraz Esfahan Yaz d Kerman Rafha 5 0 IRAQ SAU DI AR ABIA OM AN EM IRA TES JO RDAN SYRIA PAKI ST AN

Laboratory Test Requirements for Marine Shock Isolation Seats

DTIC Science & Technology

2015-05-01

presented at Sensors Expo Chicago , June 9, 2008. 7. Judd, Bob, Everything You Ever Wanted to Know about Data Acquisition, Parts One and Two, United...Washington, DC 20593-7324 Attn: David Shepard Defense Technical Information Center 8725 John J. Kingman Road Fort Belvoir, VA 22060-6218 # # 2

Experience with recurrent respiratory papillomatosis in a developing country: impact of tracheostomy.

PubMed

Orji, Foster Tochukwu; Okorafor, Ijeoma A; Akpeh, James O

2013-02-01

The frequent relapses of recurrent respiratory papillomatosis (RRP) sometimes demand repeated surgical excision with tracheostomy. This situation plays a vital role in the management of RRP in developing countries such as ours because of late presentation. This study was conducted to evaluate our experience with RRP and to determine the incidence and impact of tracheostomy in the overall management and outcomes of our patients. The records of 59 patients with histologically confirmed RRP treated between 1994 and 2008 at our tertiary institution were reviewed. We collected data such as age at onset, tracheostomy frequency and duration, number of required surgical excisions, papilloma spread to the lower airways. Patients' characteristics and the course of the disease were compared between a juvenile-onset papillomatosis (JoRRP) group and an adult-onset group (AdRRP). Overall, 68 % of our patients were in the JoRRP group (ages 2-11 years, mean 6 years). The other 32 % were 22-58 years of age (AdRRP group). Two cases of JoRRP continued into adult life. Multiple RRP dominated in the JoRRP group (93 %), whereas solitary papillomas predominated in the AdRRP group (63 %). Tracheostomy was performed because of upper airway obstruction in 42 % of our patients, with children accounting for 72 %. The mean duration of tracheostomy was 3.5 months, with 80 % lasting <4 months. Significantly more JoRRP patients had severe upper airway obstruction, required tracheostomy, and underwent multiple surgical excisions (p = 0.04, 0.02, and 0.009, respectively). Tracheobronchial spread occurred in a patient with prolonged tracheostomy. Multiple laryngeal papillomatosis clearly followed a more severe and less predictable course than the solitary type in both groups. Although there was a high incidence of tracheostomy in this study, short-duration tracheostomies accounted for the low incidence of extralaryngeal spread.

Divergent Effects of Neutrophils on Fas-Induced Pulmonary Inflammation, Apoptosis, and Lung Damage.

PubMed

Bruns, Bastian; Hönle, Theresia; Kellermann, Philipp; Ayala, Alfred; Perl, Mario

2017-02-01

Pulmonary Fas activation is essential in the pathogenesis of the acute respiratory distress syndrome. It remains unclear whether Fas-induced lung injury is dependent on neutrophils or mainly triggered by epithelial cell apoptosis. The contribution of lung epithelial cells (LEC) and alveolar macrophages (AM) remains elusive.Mice were neutrophil reduced prior to intratracheal instillation of Fas-activating (Jo2) or isotype antibody for 6 or 18 h. LEC and AM were incubated with Jo2 and in the presence of nuclear factor kappa B, p-38 mitogen activated protein kinase (p38MAPK), or extracellular signal regulating kinase 1/2 (ERK1/2) inhibitors. Cytokines were assessed by cytometric bead array or ELISA. Apoptosis was quantified via active caspase-3 Western blotting and Terminal Deoxynucleotide Transferase dUTP Nick End Labeling (TUNEL). Lung injury was assessed by bronchoalveolar lavage fluid (BALF) protein concentration and lung histology.KC, IL-6, and MCP-1 were markedly increased in lung, plasma, and BALF 18 h after Jo2 in the presence of neutrophils; in neutrophil-reduced mice lungs, MCP-1, but not KC or IL-6, was even further enhanced. Six hours after Jo2, BALF protein was markedly increased only in the presence of neutrophils. Apoptosis remained unaffected by neutrophil reduction. AM released MCP-1 and underwent apoptosis at lower concentrations of Jo2 than LEC. Inhibition of p38MAPK significantly increased, while inhibition of ERK1/2 reduced AM and LEC apoptosis.In conclusion, neutrophils are a necessary component of Fas-induced lung damage, while not affecting lung apoptosis directly per se. LEC display higher resistance to Fas-triggered inflammation and apoptosis than AM.

Ursodeoxycholyl Lysophosphatidylethanolamide Protects Against CD95/FAS-Induced Fulminant Hepatitis.

PubMed

Utaipan, Tanyarath; Otto, Ann-Christin; Gan-Schreier, Hongying; Chunglok, Warangkana; Pathil, Anita; Stremmel, Wolfgang; Chamulitrat, Walee

2017-08-01

Increased activation of CD95/Fas by Fas ligand in viral hepatitis and autoimmunity is involved in pathogenesis of fulminant hepatitis and liver failure. We designed a bile-acid phospholipid conjugate ursodeoxycholyl lysophosphatidylethanolamide (UDCA-LPE with LPE containing oleate at the sn-1) as a hepatoprotectant that was shown to protect against fulminant hepatitis induced by endotoxin. We herein further assessed the ability of UDCA-LPE to prevent death receptor CD95/Fas-induced fulminant hepatitis. C57BL/6 mice were intravenously administered with CD95/Fas agonistic monoclonal antibody (Jo-2) with or without 1 h pretreatment with 50 mg/kg UDCA-LPE. Jo-2 administration caused massive hepatocyte damage as seen by histology, and this was associated with a significant decrease in hepatic phosphatidylcholine (PC), lysoPC, and lysophosphatidylethanolamine levels. By histology, UDCA-LPE pretreatment improved hepatocyte damage and restored the loss of these phospholipids in part by a mechanism involving an inhibition of cytosolic phospholipaseA2 expression. Accordingly, Jo-2 treatment increased hepatic expression of cleaved caspase 8, caspase 3, and poly (ADP-Ribose) polymerase-1, and on the other hand decreased that of anti-apoptotic cellular FLICE-inhibitory protein. UDCA-LPE pretreatment was able to reverse all these changes. Moreover, UDCA-LPE attenuated inflammatory response by lowering the levels of Jo-2-induced proinflammatory cytokines TNF-α, IL-6, and IL-1β in liver and serum. UDCA-LPE was also able to decrease the levels of stimulated Th1/Th17 cytokines in Jo-2-primed isolated splenocytes. Taken together, UDCA-LPE exhibited potent anti-inflammatory effects against CD95/Fas-induced fulminant hepatitis.

GASP. IV. A Muse View of Extreme Ram-pressure-stripping in the Plane of the Sky: The Case of Jellyfish Galaxy JO204

NASA Astrophysics Data System (ADS)

Gullieuszik, Marco; Poggianti, Bianca M.; Moretti, Alessia; Fritz, Jacopo; Jaffé, Yara L.; Hau, George; Bischko, Jan C.; Bellhouse, Callum; Bettoni, Daniela; Fasano, Giovanni; Vulcani, Benedetta; D’Onofrio, Mauro; Biviano, Andrea

2017-09-01

In the context of the GAs Stripping Phenomena in galaxies with Muse (GASP) survey, we present the characterization of JO204, a jellyfish galaxy in A957, a relatively low-mass cluster with M=4.4× {10}14 {M}ȯ . This galaxy shows a tail of ionized gas that extends up to 30 kpc from the main body in the opposite direction of the cluster center. No gas emission is detected in the galaxy outer disk, suggesting that gas-stripping is proceeding outside-in. The stellar component is distributed as a regular disk galaxy; the stellar kinematics shows a symmetric rotation curve with a maximum radial velocity of 200 km s‑1 out to 20 kpc from the galaxy center. The radial velocity of the gas component in the central part of the disk follows the distribution of the stellar component; the gas kinematics in the tail retains the rotation of the galaxy disk, indicating that JO204 is moving at high speed in the intracluster medium. Both the emission and radial-velocity maps of the gas and stellar components indicate ram-pressure as the most likely primary mechanism for gas-stripping, as expected given that JO204 is close to the cluster center and it is likely at the first infall in the cluster. The spatially resolved star formation history of JO204 provides evidence that the onset of ram-pressure-stripping occurred in the last 500 Myr, quenching the star formation activity in the outer disk, where the gas has been already completely stripped. Our conclusions are supported by a set of hydrodynamic simulations.

A mammalian tRNAHis-containing antigen is recognized by the polymyositis-specific antibody anti-Jo-1.

PubMed Central

Rosa, M D; Hendrick, J P; Lerner, M R; Steitz, J A; Reichlin, M

1983-01-01

The mammalian cell antigen reactive with the autoantibody anti-Jo-1 has been shown to contain tRNAHis. The RNA sequence of this human and mouse cell tRNA was determined in a search for unusual features that might be related to antigenicity. The 5' terminal nucleotide is unique among other sequenced tRNAs in that it is a methylated guanine. The presence of the hypermodified base queuine, which occurs in the wobble position of the anticodon of tRNAHis from several species, was not detected in the tRNAHis immunoprecipitated by anti-Jo-1 from either human HeLa or mouse Friend erytholeukemia cell extracts. The binding of protein(s) appears to confer antigenicity on tRNAHis since either proteinase K treatment or phenol extraction resulted in the loss of immunoprecipitability. However, we have not succeeded in identifying an antigenic protein, and we find that the antigenic complex is not resolved from purified tRNAHis by Sephacryl S-200 column chromatography. Immunofluorescence studies indicate that the antigenic form of tRNAHis is located preferentially in the mammalian cell cytoplasm. The results presented here are discussed in light of an earlier report (1) on the nature of the Jo-1 antigen. Images PMID:6188108

Chronicle of Higher Education. Volume 51, Number 7, October 8, 2004

ERIC Educational Resources Information Center

Chronicle of Higher Education, 2004

2004-01-01

"Chronicle of Higher Education" presents an abundant source of news and information for college and university faculty members and administrators. This October 8, 2004 issue of "Chronicle of Higher Education" includes the following articles: (1) "Game for Anything" (Ruggill, Judd Ethan; Neelakantan, Shailaja); (2)…

IM and Q-D Rules: An Analysis by French Club MURAT

DTIC Science & Technology

1996-08-01

and Q-D Rules: An Analysis by French Club Murat 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER...IM(1) AND Q-D RULES: AN ANALYSIS BY FRENCH CLUB MURAT by Jean ISLER (2) - Jean G. GOLIGER (3) - Daniel BOCHAND (4) Georges QUEROL (5) - Louis PICARD...6) and Joël FERRON (7) CLUB MURAT - BP 129 78 148 VELIZY CEDEX - FRANCE Tel : (33) - (1) 39.46.15.50 Fax : (33) - (1) 39.46.15.38 ABSTRACT The

An Alternative Approach for Nonlinear Latent Variable Models

ERIC Educational Resources Information Center

Mooijaart, Ab; Bentler, Peter M.

2010-01-01

In the last decades there has been an increasing interest in nonlinear latent variable models. Since the seminal paper of Kenny and Judd, several methods have been proposed for dealing with these kinds of models. This article introduces an alternative approach. The methodology involves fitting some third-order moments in addition to the means and…

Irrigation and cultivar effects in no-till, cover crop, and conventional tillage systems in Arkansas Cotton.

USDA-ARS?s Scientific Manuscript database

This field experiment was conducted in association with a long term tillage study established in fall 2007 at the Judd Hill Foundation Research Farm in Northeast Arkansas to assess agronomic and environmental impacts of conservation tillage systems. In component studies in 2016 we evaluated performa...

Focus: Film in the English and Language Arts Classroom.

ERIC Educational Resources Information Center

Mullican, James S., Ed.

1976-01-01

The articles collected in this issue are devoted to the topic of film in the English and language arts classroom. Titles include "Film Study: Some Problems and Approaches" (Judd Chesler), "The New Basic Skill: Film" (Harold M. Foster), "Caveat Viewer: Developing Viewing Perceptions" (Edward S. Dermon), "Shreds and Patches: Improvised Textbook"…

Peripheral absolute threshold spectral sensitivity in retinitis pigmentosa.

PubMed Central

Massof, R W; Johnson, M A; Finkelstein, D

1981-01-01

Dark-adapted spectral sensitivities were measured in the peripheral retinas of 38 patients diagnosed as having typical retinitis pigmentosa (RP) and in 3 normal volunteers. The patients included those having autosomal dominant and autosomal recessive inheritance patterns. Results were analysed by comparisons with the CIE standard scotopic spectral visibility function and with Judd's modification of the photopic spectral visibility function, with consideration of contributions from changes in spectral transmission of preretinal media. The data show 3 general patterns. One group of patients had absolute threshold spectral sensitivities that were fit by Judd's photopic visibility curve. Absolute threshold spectral sensitivities for a second group of patients were fit by a normal scotopic spectral visibility curve. The third group of patients had absolute threshold spectral sensitivities that were fit by a combination of scotopic and photopic spectral visibility curves. The autosomal dominant and autosomal recessive modes of inheritance were represented in each group of patients. These data indicate that RP patients have normal rod and/or cone spectral sensitivities, and support the subclassification of patients described previously by Massof and Finkelstein. PMID:7459312

Joint Operations 2030 - Phase III Report: The JO 2030 Capability Set (Operations interarmees 2030 - Rapport Phase III: L’ensemble capacitaire JO 2030)

DTIC Science & Technology

2011-04-01

a ‘strategy as process’ manner to develop capabilities that are flexible, adaptable and robust. 3.4 Future structures The need for agile...to develop models of the future security environment 3.4.10 Planning Under Deep Uncertainty Future structures The need for agile, flexible and... Organisation NEC Network Enabled Capability NGO Non Government Organisation NII Networking and Information Infrastructure PVO Private Voluntary

UVIT view of ram-pressure stripping in action: Star formation in the stripped gas of the GASP jellyfish galaxy JO201 in Abell 85

NASA Astrophysics Data System (ADS)

George, K.; Poggianti, B. M.; Gullieuszik, M.; Fasano, G.; Bellhouse, C.; Postma, J.; Moretti, A.; Jaffé, Y.; Vulcani, B.; Bettoni, D.; Fritz, J.; Côté, P.; Ghosh, S. K.; Hutchings, J. B.; Mohan, R.; Sreekumar, P.; Stalin, C. S.; Subramaniam, A.; Tandon, S. N.

2018-06-01

Jellyfish are cluster galaxies that experience strong ram-pressure effects that strip their gas. Their Hα images reveal ionized gas tails up to 100 kpc, which could be hosting ongoing star formation. Here we report the ultraviolet (UV) imaging observation of the jellyfish galaxy JO201 obtained at a spatial resolution ˜ 1.3 kpc. The intense burst of star formation happening in the tentacles is the focus of the present study. JO201 is the "UV-brightest cluster galaxy" in Abell 85 (z ˜ 0.056) with knots and streams of star formation in the ultraviolet. We identify star forming knots both in the stripped gas and in the galaxy disk and compare the UV features with the ones traced by Hα emission. Overall, the two emissions remarkably correlate, both in the main body and along the tentacles. Similarly, also the star formation rates of individual knots derived from the extinction-corrected FUV emission agree with those derived from the Hα emission and range from ˜ 0.01 -to- 2.07 M⊙ yr-1. The integrated star formation rate from FUV flux is ˜ 15 M⊙ yr-1. The unprecedented deep UV imaging study of the jellyfish galaxy JO201 shows clear signs of extraplanar star-formation activity due to a recent/ongoing gas stripping event.

Characteristics of interstitial lung disease in SS-A positive/Jo-1 positive inflammatory myopathy patients.

PubMed

Váncsa, Andrea; Csípo, I; Németh, J; Dévényi, K; Gergely, L; Dankó, K

2009-07-01

The strongest predictive factor for the development of interstitial lung disease (ILD) in myositis (IIM) patients is the presence of different antisynthetase antibodies. The aim of this study was to compare the clinical characteristics, radiological findings and therapeutic response between the anti-SS-A positive and negative antisynthetase syndrome (ASS) patients. A prospective study of 315 IIM patients was conducted including 27 anti-Jo-1 positive ASS patients. Mean disease duration was 46.6 (range 4-198) months. All patients fulfilled the classification criteria for IIM. All patients underwent chest radiography, pulmonary function tests and HRCT at he time of diagnosis and 6 months after the immunosuppressive therapy. Routine laboratory tests, RF, ANA, anti-ENA, anti-SS-A, anti-histidyl-transfer RNA antibody (Jo-1) measurements were performed in all patients. ILD was found to be present in 70.4% of ASS patients. The anti-SS-A negative ASS group had a more frequent association with alveolitis and responded well to immunosuppressive therapy (p < 0.05). HRCT scan showed more fibrosis in the SS-A positive group. 15.8% of patients died due to pulmonary or cardiac complications. In conclusion, coexistence of anti-SS-A and anti-Jo-1 antibody may be a good predictor for a more coarse and severe ILD in IIM patients who require a more aggressive approach in therapy.

Prototype Technology for Monitoring Volatile Organics. Volume 1.

DTIC Science & Technology

1988-03-01

117, pp. 285-294. Grote, J.O. and Westendorf , R.G., "An Automatic Purge and Trap Concentrator," American Laboratory, December 1979. Khromchenko, Y.L...Environmental Monitoring and Support Laboratory, Office of Research and Development, Cincinnati, OH. Westendorf , R.G., "Closed-loop Stripping Analysis...Technique and Applications," American Laboratory, December 1982. Westendorf , R.G., "Development Application of A Semi-Automatic Purge and Trap Concentrator

Lubricant Evaluation and Performance

DTIC Science & Technology

1989-04-01

sample is first diluted with a solution of bis[(dimethylamino)dithiobenzil] nickel (BDN). When cumene hydroperoxide is added to the oil/BDN solution...ANALYSIS Additive A used in polyphenyl ethers is among a group of metal containing compounds including phenyl nitrosalicyamine adducts of nickel and...1963. 6. Stemniski, J.R., Wilson, G.R., Smith J.O. and McHugh , K.L., "Antioxidants for High Temperature Lubricants," ASLE Trans., 7, p 43 (1964). 7

MapMaker and PathTracer for tracking carbon in genome-scale metabolic models

PubMed Central

Tervo, Christopher J.; Reed, Jennifer L.

2016-01-01

Constraint-based reconstruction and analysis (COBRA) modeling results can be difficult to interpret given the large numbers of reactions in genome-scale models. While paths in metabolic networks can be found, existing methods are not easily combined with constraint-based approaches. To address this limitation, two tools (MapMaker and PathTracer) were developed to find paths (including cycles) between metabolites, where each step transfers carbon from reactant to product. MapMaker predicts carbon transfer maps (CTMs) between metabolites using only information on molecular formulae and reaction stoichiometry, effectively determining which reactants and products share carbon atoms. MapMaker correctly assigned CTMs for over 97% of the 2,251 reactions in an Escherichia coli metabolic model (iJO1366). Using CTMs as inputs, PathTracer finds paths between two metabolites. PathTracer was applied to iJO1366 to investigate the importance of using CTMs and COBRA constraints when enumerating paths, to find active and high flux paths in flux balance analysis (FBA) solutions, to identify paths for putrescine utilization, and to elucidate a potential CO2 fixation pathway in E. coli. These results illustrate how MapMaker and PathTracer can be used in combination with constraint-based models to identify feasible, active, and high flux paths between metabolites. PMID:26771089

An Investigation of the Distribution of Radiation Scattered by Optical Surfaces

DTIC Science & Technology

1975-08-01

Profile Inversion Workshop, Ames Research Center, Moffett Field, California, L. Colin, ed., pp. 6-34 to 6-37 ( NASA TM X-62, 150). (Available from th...Surface EM Scattering Solutions," IEEE Trans. AP-21:393-396. Judd, D. B., 1967, "Terms, Definitions, and Symbols in Reflectometry ," J. Opt. Soc. Am. 57:445

Miconia bullotricha and M. hirtistyla, two new species of Miconia sect. Lima (Miconieae, Melastomataceae) from eastern Cuba

PubMed Central

Majure, Lucas C.; Bécquer, Eldis R.; Judd, Walter S.

2014-01-01

Abstract We describe two new species in Miconia sect. Lima, Miconia bullotricha Bécquer & Majure and Miconia hirtistyla Majure & Judd, from eastern, Cuba. We also provide illustrations and distribution maps for the two species, as well as a key to members of the Lima clade on Cuba. PMID:24526849

Clinical Commentary by Dorothy Judd, Child and Adolescent and Couple Psychotherapist

ERIC Educational Resources Information Center

Judd, Dorothy

2010-01-01

This article presents the author's observations on a clinical extract which describes a child psychotherapist working with Maya, a seriously ill child, in a hospital. The author said that the hospital setting raises the question of what it is like to apply child psychotherapists' thinking within a hospital setting, and how they adapt the way they…

Adaptability of selected tree species planted in Hawaii forests

Treesearch

Robert E. Nelson; Thomas H. Schubert

1972-01-01

Many tree species have been introduced into Hawaii from around the world (Bryan and Walker i962, Hillebrand 1965, St. John 1973). Trial introductions of new species for various forestry purposes began in the 19th century and are still continuing. Walker (1887), Judd (1915); Lyon (1929), Zschokke (1930), Bryan (1947), and Whitesell (1971, 1974), among others, have...

A Dwarf Planet Class Object in the 21:5 Resonance with Neptune

NASA Astrophysics Data System (ADS)

Holman, Matthew J.; Payne, Matthew J.; Fraser, Wesley; Lacerda, Pedro; Bannister, Michele T.; Lackner, Michael; Chen, Ying-Tung; Lin, Hsing Wen; Smith, Kenneth W.; Kokotanekova, Rosita; Young, David; Chambers, K.; Chastel, S.; Denneau, L.; Fitzsimmons, A.; Flewelling, H.; Grav, Tommy; Huber, M.; Induni, Nick; Kudritzki, Rolf-Peter; Krolewski, Alex; Jedicke, R.; Kaiser, N.; Lilly, E.; Magnier, E.; Mark, Zachary; Meech, K. J.; Micheli, M.; Murray, Daniel; Parker, Alex; Protopapas, Pavlos; Ragozzine, Darin; Veres, Peter; Wainscoat, R.; Waters, C.; Weryk, R.

2018-03-01

We report the discovery of an H r = 3.4 ± 0.1 dwarf planet candidate by the Pan-STARRS Outer Solar System Survey. 2010 JO179 is red with (g ‑ r) = 0.88 ± 0.21, roughly round, and slowly rotating, with a period of 30.6 hr. Estimates of its albedo imply a diameter of 600–900 km. Observations sampling the span between 2005 and 2016 provide an exceptionally well determined orbit for 2010 JO179, with a semimajor axis of 78.307 ± 0.009 au; distant orbits known to this precision are rare. We find that 2010 JO179 librates securely within the 21:5 mean-motion resonance with Neptune on 100 Myr timescales, joining the small but growing set of known distant dwarf planets on metastable resonant orbits. These imply a substantial trans-Neptunian population that shifts between stability in high-order resonances, the detached population, and the eroding population of the scattering disk.

Expression of BAFF receptors in muscle tissue of myositis patients with anti-Jo-1 or anti-Ro52/anti-Ro60 autoantibodies.

PubMed

Kryštůfková, Olga; Barbasso Helmers, Sevim; Venalis, Paulius; Malmström, Vivianne; Lindroos, Eva; Vencovský, Jiří; Lundberg, Ingrid E

2014-10-10

Anti-Jo-1 and anti-Ro52 autoantibodies are common in patients with myositis, but the mechanisms behind their production are not known. Survival of autoantibody-producing cells is dependent on B-cell-activating factor of the tumour necrosis factor family (BAFF). BAFF levels are elevated in serum of anti-Jo-1-positive myositis patients and are influenced by type-I interferon (IFN). IFN-producing cells and BAFF mRNA expression are present in myositis muscle. We investigated expression of the receptors for BAFF in muscle tissue in relation to anti-Jo-1 and anti-Ro52/anti-Ro60 autoantibodies and type-I IFN markers. Muscle biopsies from 23 patients with myositis selected based on autoantibody profile and 7 healthy controls were investigated for expression of BAFF receptor (BAFF-R), B-cell maturation antigen (BCMA) and transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI). Nineteen samples were assessed for plasma (CD138) and B-cell (CD19) markers. The numbers of positive cells per area were compared with the expression of plasmacytoid dendritic cell (pDC) marker blood dendritic cell antigen-2 (BDCA-2) and IFNα/β-inducible myxovirus resistance-1 protein (MX-1). BAFF-R, BCMA and TACI were expressed in five, seven and seven patients, respectively, and more frequently in anti-Jo-1-positive and/or anti-Ro52/anti-Ro60-positive patients compared to controls and to patients without these autoantibodies (P = BAFF-R: 0.007, BCMA: 0.03 and TACI: 0.07). A local association of receptors with B and plasma cells was confirmed by confocal microscopy. The numbers of CD138-positive and BCMA-positive cells were correlated (r = 0.79; P = 0.001). Expression of BDCA-2 correlated with numbers of CD138-positive cells and marginally with BCMA-positive cells (r = 0.54 and 0.42, respectively; P = 0.04 and 0.06, respectively). There was a borderline correlation between the numbers of positively stained TACI cells and MX-1 areas (r = 0.38, P = 0.08). The expression pattern of receptors for BAFF on B and plasma cells in muscle suggests a local role for BAFF in autoantibody production in muscle tissues of patients with myositis who have anti-Jo-1 or anti-Ro52/anti-Ro60 autoantibodies. BAFF production could be influenced by type-I IFN produced by pDCs. Thus, B-cell-related molecular pathways may participate in the pathogenesis of myositis in this subset of patients.

Life-Cycle Cost Database Design and Sample Data Development.

DTIC Science & Technology

1981-02-01

inventory . Table 5 lists the 35 installations studied in the Red Book analysis, their MACOMs, and their geographical regions. For FY79, the total M&R cost...ACTIVITY TITLE fASJRr JUANTITY ZJS5 ACIA ACRLZYIES A 3,P 02 5 .5 .4 s e,on’.? .jo000 OPERATIO OFM U TILITIES PjP 3(R0 20,9.3 5 o.e 2 .55 .o1O0 I0TER

Design Concept for the Advanced Radar Test Bed (ARTB). Volume 2. Appendices.

DTIC Science & Technology

1994-12-31

A (Statement of Work) to ARTB Technical Report z~ 0w W W = w Cl) LU)u ui Mi 0.0r- -a ZeC 0 (WY) zj M CU 0=. 3 ""Jo 0 XEOWE 4(06 0 L Scientific ~ ~ C...Analysis from Theory to Software, A. K. Peters Ltd, May 1994) which allow wa.vetes to be se-n as Pvstm implementation tools, rather than mathematical

[Analytic study of dot blotting for the detection of anti-Jo-1, anti-M2, anti-ribosomes and anti-LKM].

PubMed

Huguet, S; Sghiri, R; Ballot, E; Johanet, C

2004-01-01

The Cyto-Dot 4 HM043 kit commercialised by BMD, has replaced the Cyto-Dot HM010 kit that allowed three auto-antibodies detection (anti-Jo-1, anti-M2 and anti-ribosomal protein). Detection of anti-LKM1 auto-antibody was added. These four auto-antibodies have in common only the intracytoplasmic localisation of their respective antigen. The aim of our study was to evaluate this new kit using 104 sera and to compare our results with reference techniques (indirect immunofluorescence IF for anti-M2, anti-ribosomal protein and anti-LKM1, double immunodiffusion ID for anti-Jo-1 and anti-LKM1, western blotting WB for anti-M2) and with Cyto-Dot HM010. The one hundred and four sera were divided into five groups: Group I (n = 12) with anti-Jo-1 detected by ID; Group II (n = 28) with 26 anti-M2 positive by IF and WB, 2 anti-M2 positive only by WB; Group III (n = 10) with anti-ribosomal protein detected by IF 5 of which precipitated by ID; Group IV (n = 32) with anti-LKM1 by IF and ID divided into 18 AIH2 and 14 HCV; Group V (n = 22) consisting of 14 healthy individuals and 8 patients with hypergammaglobulinemia. Results of this study are similar to those of Cyto-Dot HM010 for the three auto-antibodies already in use. Cyto-Dot 4 is a very good anti-LKM1 confirmation method as it is ID. Copyright John Libbey Eurotext 2003.

Myositis-specific autoantibodies are specific for myositis compared to genetic muscle disease.

PubMed

Mammen, Andrew L; Casciola-Rosen, Livia; Christopher-Stine, Lisa; Lloyd, Thomas E; Wagner, Kathryn R

2015-12-01

To determine the specificity of myositis-specific autoantibodies (MSAs) for autoimmune myopathy compared with inherited muscle diseases. Serum samples from 47 patients with genetically confirmed inherited muscle diseases were screened for the most common MSAs, including those recognizing TIF1γ, NXP2, Mi2, MDA5, Jo1, SRP, and HMGCR. We compared these results with the findings in a cohort of patients with dermatomyositis (DM) previously screened for anti-TIF1γ, -NXP2, -Mi2, -MDA5, and -Jo1. Overall, the presence of anti-TIF1γ, -NXP2, -Mi2, -MDA5, or -Jo1 was 96% specific and 67% sensitive for DM compared to patients with genetic muscle diseases. No patients with inherited muscle disease had anti-SRP or anti-HMGCR autoantibodies. Only 2 patients with genetic muscle disease had a MSA. One patient with anti-Mi2 autoantibodies had both genetically confirmed facioscapulohumeral dystrophy and dermatomyositis based on a typical skin rash and partial response to immunosuppressive medications. A second patient with anti-Jo-1 autoantibodies had both genetically defined limb-girdle muscular dystrophy type 2A (i.e., calpainopathy) and a systemic autoimmune process based on biopsy-confirmed lupus nephritis, sicca symptoms, and anti-Ro52 autoantibodies. The MSAs tested for in this study are highly specific for autoimmune muscle disease and are rarely, if ever, found in patients who only have genetic muscle disease. In patients with genetic muscle disease, the presence of a MSA should suggest the possibility of a coexisting autoimmune process.

Myositis-specific autoantibodies are specific for myositis compared to genetic muscle disease

PubMed Central

Casciola-Rosen, Livia; Christopher-Stine, Lisa; Lloyd, Thomas E.; Wagner, Kathryn R.

2015-01-01

Objective: To determine the specificity of myositis-specific autoantibodies (MSAs) for autoimmune myopathy compared with inherited muscle diseases. Methods: Serum samples from 47 patients with genetically confirmed inherited muscle diseases were screened for the most common MSAs, including those recognizing TIF1γ, NXP2, Mi2, MDA5, Jo1, SRP, and HMGCR. We compared these results with the findings in a cohort of patients with dermatomyositis (DM) previously screened for anti-TIF1γ, -NXP2, -Mi2, -MDA5, and -Jo1. Results: Overall, the presence of anti-TIF1γ, -NXP2, -Mi2, -MDA5, or -Jo1 was 96% specific and 67% sensitive for DM compared to patients with genetic muscle diseases. No patients with inherited muscle disease had anti-SRP or anti-HMGCR autoantibodies. Only 2 patients with genetic muscle disease had a MSA. One patient with anti-Mi2 autoantibodies had both genetically confirmed facioscapulohumeral dystrophy and dermatomyositis based on a typical skin rash and partial response to immunosuppressive medications. A second patient with anti-Jo-1 autoantibodies had both genetically defined limb-girdle muscular dystrophy type 2A (i.e., calpainopathy) and a systemic autoimmune process based on biopsy-confirmed lupus nephritis, sicca symptoms, and anti-Ro52 autoantibodies. Conclusions: The MSAs tested for in this study are highly specific for autoimmune muscle disease and are rarely, if ever, found in patients who only have genetic muscle disease. In patients with genetic muscle disease, the presence of a MSA should suggest the possibility of a coexisting autoimmune process. PMID:26668818

A role for acoustic distortion in novel rapid frequency modulation behaviour in free-flying male mosquitoes.

PubMed

Simões, Patrício M V; Ingham, Robert A; Gibson, Gabriella; Russell, Ian J

2016-07-01

We describe a new stereotypical acoustic behaviour by male mosquitoes in response to the fundamental frequency of female flight tones during mating sequences. This male-specific free-flight behaviour consists of phonotactic flight beginning with a steep increase in wing-beat frequency (WBF) followed by rapid frequency modulation (RFM) of WBF in the lead up to copula formation. Male RFM behaviour involves remarkably fast changes in WBF and can be elicited without acoustic feedback or physical presence of the female. RFM features are highly consistent, even in response to artificial tones that do not carry the multi-harmonic components of natural female flight tones. Comparison between audiograms of the robust RFM behaviour and the electrical responses of the auditory Johnston's organ (JO) reveals that the male JO is tuned not to the female WBF per se but, remarkably, to the difference between the male and female WBFs. This difference is generated in the JO responses as a result of intermodulation distortion products (DPs) caused by non-linear interaction between male-female flight tones in the vibrations of the antenna. We propose that male mosquitoes rely on their own flight tones in making use of DPs to acoustically detect, locate and orientate towards flying females. We argue that the previously documented flight-tone harmonic convergence of flying male and female mosquitoes could be a consequence of WBF adjustments so that DPs generated through flight-tone interaction fall within the optimal frequency ranges for JO detection. © 2016. Published by The Company of Biologists Ltd.

Analysis and Application of an Underwater Optical-Ranging System

DTIC Science & Technology

1992-09-01

sin 20 (3.2) 0 2 2 The direction in which this is maximized or minimized is found by differentiating with respect to 0 and setting to zero _ = 0 (3.3...H.O. Torsen , K. Thoresen, "Laser Imaging Technology for Subsea Inspection: Principles and Applications," IRMI/ROV90 Coiference, November 1990. [6...J.O. Klepsvik, H.O. Torsen , "Recent Advances in Accurate Underwater Mapping and Inspection Techniques," International Ocean Technology Congress, January

From School-Culture-to-Family-Culture: Reflections on Four Generations of a Deweyan Education in Hawai'i

ERIC Educational Resources Information Center

Makaiau, Amber Strong

2015-01-01

In 1918, the author's great great aunt, Sophie Judd Cooke founded a small progressive school in Honolulu. Her brother Henry named it Hanahau'oli School, which means joyful work school. In this essay the author's mother, Linda Summers Strong and the author reflect on the impact of Hanahau'oli School's Deweyan approach to education on the…

Reactive Behavior of Explosive Billets in Deflagration Tube of Varied Confinements

NASA Astrophysics Data System (ADS)

Hu, Haibo; Guo, Yingwen; Li, Tao; Fu, Hua; Shang, Hailin; Wen, Shanggang; Qiu, Tian; LaboratoryShock Wave; Detonation Physics Research Team

2017-06-01

The deflagration process of small size cylinder billets of pressed HMX-based explosive JO-9159 and the deflagration tube wall deformation is recorded by combined pressure velocity-meter high-speed frame photographic and radiographic diagnostic system. The influence of confinement structure strength on deflagration evolution behavior is compared with analysis of convective flame propagation along the slot between explosive billet and confinement wall.The follow-up reaction inside the cracks on the initiation site end surface on the side surfaces and between the end surfaces of explosive billets is restored with the analysis results of post experimental explosive billet remains.

Simulations to Evaluate Accuracy and Patient Dose in Neutron-Stimulated, Emission-Computed Tomography (NSECT) for Diagnosis of Breast Cancer

DTIC Science & Technology

2008-04-01

tissues , Cancer 52 (3) (1983) 508. [18] J.O. Ogunlewe, D.N. Osegbe, Zinc and cadmium concentrations in indigenous blacks with normal, hypertrophic...142 (1976) 65. [10] E.J. Margalioth, J.G. Schenker, M. Chevion, Copper and zinc levels in normal and malignant tissues , Cancer 52 (5) (1983) 868. [11...Krajewska, Zinc and cadmium analysis in human prostate neoplasms, Biol. Trace Elem. Res. 59 (1–3) (1997) 145. [22] V.Y. Zaichick, T.V. Sviridova

Armed Services Board of Contract Appeals: Analysis of Sustained Decisions on DoD Supply Contract Disputes.

DTIC Science & Technology

1986-12-01

Contract Law are the primary sources of policy and interpretation, since these are the informa- tion sources relied upon by field contracting officers, in...FAR is the governing regulation of the Government [Ref. 13:pp. 1106-7]. In no other area of contract law has one party been given such complete...Washington: Government Printing Office, April 1984. 4. Mahoy, J.O., Government Contract Law , 6th ed., Gunter Air Force Station AL, Extension Course Institute

[Comparing the Application of Hema-Obs RSS to 250 Pregnancies from Obstetrics/Hematology Consultation in Centro Hospitalar São João, Portugal with the Application of Galit Sarig RSS to 90 Pregnancies from Rambam Health Care Campus, Israel].

PubMed

Salselas, Ana; Pestana, Inês; Bischoff, Francisco; Guimarães, Mariana; Andrade, Joaquim Aguiar

2015-01-01

Pregnant women with thromboembolic diseases, previous thrombotic episodes or thrombophilia family history were supervised in a multidisciplinary Obstetrics/ Hematology consultation in Centro Hospitalar São João EPE, Porto, Portugal. For the evaluation and medication of these women, a risk stratification scale was used. The aim of this study was to validate a Risk Stratification Scale and thromboprophylaxis protocol by means of comparing it with a similar scale, developed and published by Sarig. We have compared: The distribution, by risk groups, obtained through the application of the two scales on pregnant women followed at Centro Hospitalar São João, Porto, Portugal, consultation; the sensibility and specificity for each one of the scales (DeLong scale, applied to Receiver Operating Characteristic) curves; the outcomes in pregnancies followed in Hospital São João, Porto, PortugalResults: According to our Hema-Obs risk stratification scale, 29% were allocated to low-risk, 47% to high-risk and 24% to very-high-risk groups. According to Galit Sarig risk stratification scale, 24% were considered low-risk, 53% moderate, 16% high-risk and 7% as very high-risk group. In our study we observed 9% of spontaneous abortions, in comparison with 18% in the Galit Sarig cohort. From the application of Receiver Operating Characteristic curve to both risk stratification scales, the results of the calculated areas were 58,8% to our Hema-Obs risk stratification scale and 38,7% to Galit Sarig risk stratification scale, with a Delong test significancie of p = 0.0006. We concluded that Hema-Obs risk stratification scale is an effective support for clinical monitoring of therapeutic strategies.

A New Transgenic Mouse Model for Studying the Neurotoxicity of Spermine Oxidase Dosage in the Response to Excitotoxic Injury

PubMed Central

Cervelli, Manuela; Bellavia, Gabriella; D'Amelio, Marcello; Cavallucci, Virve; Moreno, Sandra; Berger, Joachim; Nardacci, Roberta; Marcoli, Manuela; Maura, Guido; Piacentini, Mauro; Amendola, Roberto; Cecconi, Francesco; Mariottini, Paolo

2013-01-01

Spermine oxidase is a FAD-containing enzyme involved in polyamines catabolism, selectively oxidizing spermine to produce H2O2, spermidine, and 3-aminopropanal. Spermine oxidase is highly expressed in the mouse brain and plays a key role in regulating the levels of spermine, which is involved in protein synthesis, cell division and cell growth. Spermine is normally released by neurons at synaptic sites where it exerts a neuromodulatory function, by specifically interacting with different types of ion channels, and with ionotropic glutamate receptors. In order to get an insight into the neurobiological roles of spermine oxidase and spermine, we have deregulated spermine oxidase gene expression producing and characterizing the transgenic mouse model JoSMOrec, conditionally overexpressing the enzyme in the neocortex. We have investigated the effects of spermine oxidase overexpression in the mouse neocortex by transcript accumulation, immunohistochemical analysis, enzymatic assays and polyamine content in young and aged animals. Transgenic JoSMOrec mice showed in the neocortex a higher H2O2 production in respect to Wild-Type controls, indicating an increase of oxidative stress due to SMO overexpression. Moreover, the response of transgenic mice to excitotoxic brain injury, induced by kainic acid injection, was evaluated by analysing the behavioural phenotype, the immunodistribution of neural cell populations, and the ultrastructural features of neocortical neurons. Spermine oxidase overexpression and the consequently altered polyamine levels in the neocortex affects the cytoarchitecture in the adult and aging brain, as well as after neurotoxic insult. It resulted that the transgenic JoSMOrec mouse line is more sensitive to KA than Wild-Type mice, indicating an important role of spermine oxidase during excitotoxicity. These results provide novel evidences of the complex and critical functions carried out by spermine oxidase and spermine in the mammalian brain. PMID:23840306

Spatial filtering and spatial primitives in early vision: an explanation of the Zöllner-Judd class of geometrical illusion.

PubMed

Morgan, M J; Casco, C

1990-10-22

The apparent length and orientation of short lines is altered when they abut against oblique lines (the Zöllner and Judd illusions). Here we present evidence that the length and orientation biases are geometrically related and probably depend upon the same underlying mechanism. Measurements were done with an 'H' figure, in which the apparent length and orientation of the cross-bar was assessed by the method of adjustment while the orientation of the outer flanking lines was varied. When the flanking lines are oblique the apparent length of the central line is reduced and its orientation is shifted so that it appears more nearly at right-angles to the obliques than is in fact the case. Measurements of the orientation and length effects were made in three observers, over a range of flanking-line angles (90, 63, 45, 34 and 27 deg) and central line lengths (9, 17, 33 and 67 arc min). The biases increased with the tilt of the flanking-lines, and decreased with central line length. The extent of the length bias could be accurately predicted from the angular shift by simple trigonometry. We describe physiological and computational models to account for the relation between the orientation and length biases.

Development of a FDA-Approved Pharmaceutical to Treat Noise-Induced Hearing Loss

DTIC Science & Technology

2014-08-13

be reduced by 40 dB, resulting in a 115 dB SPL of noise exposure for personnel servicing the flight operations. (5) BODY: Scientific and Technical...80 . 70 . Zklh ! 60 i - 41oHz 81611 16KH.I i 50 ·-·-----~~---- ! 40 l i JO • 1 zo ------------ 10 0 Z IoHz 41oHz 81oHz 16KHz...15•0/0I ~ 40 \\-- •• -----~r-----/----- -n-151131!0/JOOJ ! JO : 1 zo ’------~~--------- 10 0 1 IoHz 41oHz 8IoHz 16KHz 2 Main Effect: • • • -+-(S.0

A case of anti-Jo1 myositis with pleural effusions and pericardial tamponade developing after exposure to a fermented Kombucha beverage.

PubMed

Derk, Chris T; Sandorfi, Nora; Curtis, Mark T

2004-08-01

The pathogenesis of the idiopathic inflammatory myopathies has been postulated to be an environmental trigger causing the expression of the disease in a genetically predisposed patient. We report a case of anti-Jo1 antibody-positive myositis which was associated with pleural effusions, pericardial effusion with tamponade, and 'mechanic's hands', probably related to the consumption of a fermented Kombucha beverage. Kombucha 'mushroom', a symbiosis of yeast and bacteria, is postulated to be the trigger for our patient's disease owing to the proximity of his symptoms to the consumption of the Kombucha beverage.

[Myositis, polysynovitis and pulmonary fibrosis: anti-Jo-1 syndrome].

PubMed

Perrenoud, F G; Van Lindhoudt, D; Ochsner, F; Janzer, R C; Ott, H

1996-01-27

Polymyositis/dermatomyositis are rare autoimmune diseases. Classification is usually performed according to the criteria of Bohan and Peter. The occurrence of myositis-specific autoantibodies has recently been described in inflammatory myopathies. Approximately half of the patients can now be classified by these specific autoantibodies. Several of these autoantibodies (anti-aminoacyl-tRNA synthetases, anti-SRP, anti-Mi2) are strongly associated with the clinical presentation. We may expect that in the future different subsets of these diseases will be increasingly identified by serum antibodies. We report on a patient with myopathy, pulmonary fibrosis and polysynovitis, a typical clinical presentation of the anti-Jo1 syndrome (anti-synthetase syndrome).

Risk factors and anti-Toxoplasma gondii and Neospora caninum antibody occurrence in dogs in João Pessoa, Paraíba state, Northeastern Brazil.

PubMed

Brasil, Arthur Willian de Lima; Parentoni, Roberta Nunes; Silva, José Givanildo da; Santos, Carolina de Sousa Américo Batista; Mota, Rinaldo Aparecido; Azevedo, Sérgio Santos de

2018-01-01

The aim of this study was to determine the occurrence of infections due to Toxoplasma gondii and Neospora caninum and corresponding risk factors among dogs attended at veterinary clinics in the city of João Pessoa, Paraíba, northeastern Brazil. Blood samples were collected from 384 dogs that were attended at 34 veterinary clinics between April 2015 and May 2016. These two agents were diagnosed through the indirect immunofluorescence reaction (IFAT). Among the 384 animals evaluated, 37 (9.6%) were positive for T. gondii, with titers ranging from 16 to 512. Six dogs (1.6%) were positive for N. caninum, with titers of 50 to 200. Access to the streets (OR = 4.60; 95% CI = 1.74-12.20) and environments close to forested areas (OR = 2.79; 95% CI = 1.32-5.93) were found to be risk factors for T. gondii infection. The dogs attended at veterinary clinics in João Pessoa are exposed to infections caused by T. gondii and N. caninum. Dog owners should avoid having access to the street or contact with forest environments.

Coupling Climate Models and Forward-Looking Economic Models

NASA Astrophysics Data System (ADS)

Judd, K.; Brock, W. A.

2010-12-01

Authors: Dr. Kenneth L. Judd, Hoover Institution, and Prof. William A. Brock, University of Wisconsin Current climate models range from General Circulation Models (GCM’s) with millions of degrees of freedom to models with few degrees of freedom. Simple Energy Balance Climate Models (EBCM’s) help us understand the dynamics of GCM’s. The same is true in economics with Computable General Equilibrium Models (CGE’s) where some models are infinite-dimensional multidimensional differential equations but some are simple models. Nordhaus (2007, 2010) couples a simple EBCM with a simple economic model. One- and two- dimensional ECBM’s do better at approximating damages across the globe and positive and negative feedbacks from anthroprogenic forcing (North etal. (1981), Wu and North (2007)). A proper coupling of climate and economic systems is crucial for arriving at effective policies. Brock and Xepapadeas (2010) have used Fourier/Legendre based expansions to study the shape of socially optimal carbon taxes over time at the planetary level in the face of damages caused by polar ice cap melt (as discussed by Oppenheimer, 2005) but in only a “one dimensional” EBCM. Economists have used orthogonal polynomial expansions to solve dynamic, forward-looking economic models (Judd, 1992, 1998). This presentation will couple EBCM climate models with basic forward-looking economic models, and examine the effectiveness and scaling properties of alternative solution methods. We will use a two dimensional EBCM model on the sphere (Wu and North, 2007) and a multicountry, multisector regional model of the economic system. Our aim will be to gain insights into intertemporal shape of the optimal carbon tax schedule, and its impact on global food production, as modeled by Golub and Hertel (2009). We will initially have limited computing resources and will need to focus on highly aggregated models. However, this will be more complex than existing models with forward-looking economic modules, and the initial models will help guide the construction of more refined models that can effectively use more powerful computational environments to analyze economic policies related to climate change. REFERENCES Brock, W., Xepapadeas, A., 2010, “An Integration of Simple Dynamic Energy Balance Climate Models and Ramsey Growth Models,” Department of Economics, University of Wisconsin, Madison, and University of Athens. Golub, A., Hertel, T., etal., 2009, “The opportunity cost of land use and the global potential for greenhouse gas mitigation in agriculture and forestry,” RESOURCE AND ENERGY ECONOMICS, 31, 299-319. Judd, K., 1992, “Projection methods for solving aggregate growth models,” JOURNAL OF ECONOMIC THEORY, 58: 410-52. Judd, K., 1998, NUMERICAL METHODS IN ECONOMICS, MIT Press, Cambridge, Mass. Nordhaus, W., 2007, A QUESTION OF BALANCE: ECONOMIC MODELS OF CLIMATE CHANGE, Yale University Press, New Haven, CT. North, G., R., Cahalan, R., Coakely, J., 1981, “Energy balance climate models,” REVIEWS OF GEOPHYSICS AND SPACE PHYSICS, Vol. 19, No. 1, 91-121, February Wu, W., North, G. R., 2007, “Thermal decay modes of a 2-D energy balance climate model,” TELLUS, 59A, 618-626.

Nd3+-doped heavy metal oxide based multicomponent borate glasses for 1.06 μm solid-state NIR laser and O-band optical amplification applications

NASA Astrophysics Data System (ADS)

Lakshminarayana, G.; Kaky, Kawa M.; Baki, S. O.; Lira, A.; Meza-Rocha, A. N.; Falcony, C.; Caldiño, U.; Kityk, I. V.; Méndez-Blas, A.; Abas, A. F.; Alresheedi, M. T.; Mahdi, M. A.

2018-04-01

Nd3+-doped glasses in the composition (50-x) B2O3-10 PbO-10 BaO-10 Al2O3-10 ZnO-10 Na2O-(x) Nd2O3 (x = 0.0, 0.1, 0.25, 0.5, 0.75, 1.0, 1.5, and 2.0 mol %) were fabricated using melt quenching method. Upon 592 nm visible and 808 nm LD excitations, the luminescence spectra show a strong 4F3/2 → 4I11/2 (1.06 μm) emission transition, and two less intense 4F3/2 → 4I9/2 (0.89 μm) and 4F3/2 → 4I13/2 (1.331 μm) emission transitions. The intensity of such emissions increases up to 0.5 mol % Nd3+, and above this doping level, quenching occurs. For 0.5 mol % Nd3+-doped glass, following Judd-Ofelt intensity parameters and emission spectrum, AR, τR, βR and βexp, including Δλeff,σem(λp), (σem × (Δλeff)) and (σem × (τrad)), are derived for Nd3+ ion 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 fluorescence transitions. The highest σem(λp) for the 1.06 and 1.331 μm fluorescence bands are found to be 6.216 × 10-20 and 2.295 × 10-20cm2, respectively. The 4F3/2 level lifetimes are found to decrease with an increase in Nd2O3 content and the decay curves of the glass up to 1.5 mol % Nd3+ exhibit single exponential nature. From 'τexp' of the Nd3+: 4F3/2 level, quantum efficiency (η), (σem × (τexp)), and saturation intensity (IS) are 48.87%, 51.09 × 10-25 cm2s and 3.67 × 108 W/m2, respectively, for the 0.5 mol % Nd3+-doped glass. Higher thermal stability, very low χ, high AR, large βexp., moderate τR, large gain bandwidth and high optical gain values indicate that 0.5 mol % Nd3+-doped glass could be a potential gain medium for solid-state NIR lasers at 1.06 μm. Moreover, for the 1.331 μm emission, large Δλeff and the theoretical gain coefficient value of 1.579 dB/cm, evaluated with an excited Nd3+ ion fractional factor of 0.6, indicate that this glass might be a promising candidate in developing O-band optical fiber amplifiers.

AWARE Wide Field View

DTIC Science & Technology

2016-04-29

G. Anderson, S. D. Feller, E . M. Vera , H. S. Son, S.-H. Youn, J. Kim, M. E . Gehm, D. J. Brady, J. M. Nichols, K. P. Judd, M. D. Duncan, J. R...scale in monocentric gigapixel cameras." Applied Optics 50(30): 5824-5833. Tremblay, E . J., et al. (2012). "Design and scaling of monocentric...cameras. Optomechanical Engineering 2013. A. E . Hatheway. 8836. Youn, S. H., et al. (2013). Efficient testing methodologies for microcameras in a

Solar photolysis of ozone to singlet D oxygen atoms

NASA Technical Reports Server (NTRS)

Blackburn, Thomas E.; Bairai, Solomon T.; Stedman, Donald H.

1992-01-01

The ground-level photolysis frequency of ozone J(O3) to produce metastable singlet D oxygen atoms (O (D-1)) is measured using a novel instrumental technique involving electrical conductivity. The O(D-1) atoms produced react with nitrous oxide (N2O) carrier gas to form higher oxides of nitrogen (NO(x)). These oxides were detected by mixing with methanol and determining the increase in electrical conductivity with a continuous-flow dual conductivity cell. Over 70 days of data were collected under varying sky conditions. The effect of temperature on J(O3) was measured. The results agree with model predictions. The effects of atmospheric aerosols, changes in overhead ozone column, and local cloudiness are discussed.

Computer Aided Approach to the Design of Y-Junction Stripline and Microstrip Ferrite Circulators

DTIC Science & Technology

1992-05-05

einO (36) n Jn(kr) J(k) A " kr J~r Finally, the Green’s function is 7 R. E. NEIDERT G(r,op ; R#¢) = X + Y X= j ZeJo(kr) 2 x Jo(kr) (37) IC n Jn(kR) - ’ n ...AD-A251 337 NRL/R ,-92-938I IIIII~ l l li i 1 11 [IIIfll li Computer Aided Approach to the Design of Y -Junction Stripline and Microstrip Ferrite...Aided Approach to the Design of Y -Junction - 62234N Stripline and Microstrip Ferrite Circulators PR - RS34R2 6. AUTHOR(S) WU - 2535-0 Robert E

Graphic/Symbol Segmentation for Group 4 Facsimile Systems.

DTIC Science & Technology

1982-04-01

age pros de Ia poemis) urn sogpal dent Is transformeode Fourier at riollo. constantste jo, lo jo a &f. ct nlo do part at d’autre de ot de o, df.. cuo...vM 16.0 ag r"o faAot whic wresouin ne av rage m3so perce loer thn eigh- - -t dauesuingh apr.msinrt f40 ii n 2 16.9 ’..* fm lom 17.1 U.7 5.6 A s o ad...infinity and MSLT set to 0 ms, the aver- *:" ’ age transmission time is 6I.S s which is 44.7 percent lower , , VI. ftavoaxAacu OF ml TWO-dIMsENSuONAL

Kassite from the Diamond Jo quarry, Magnet Cove, Hot Spring County, Arkansas: the problem of cafetite and kassite.

USGS Publications Warehouse

Evans, H.T.; Dwornik, E.J.; Milton, C.

1986-01-01

Small (<0.5 mm), brownish-pink platy rosettes and yellow spherules, in cavities in nepheline syenite at the Diamond Jo quarry, Magnet Cove, have been identified as kassite, CaTi2O4(OH)2, a mineral previously known only from the Kola Peninsula, USSR. The X-ray powder and single-crystal data and density of the Magnet Cove kassite correspond with those reported by earlier workers for cafetite, (Ca,Mg)(Fe,Al)2Ti4O12.4H2O, from Kola, but the chemical and physical properties correspond with those given in their description of kassite.-J.A.Z.

Large-scale exploratory genetic analysis of cognitive impairment in Parkinson's disease.

PubMed

Mata, Ignacio F; Johnson, Catherine O; Leverenz, James B; Weintraub, Daniel; Trojanowski, John Q; Van Deerlin, Vivianna M; Ritz, Beate; Rausch, Rebecca; Factor, Stewart A; Wood-Siverio, Cathy; Quinn, Joseph F; Chung, Kathryn A; Peterson-Hiller, Amie L; Espay, Alberto J; Revilla, Fredy J; Devoto, Johnna; Yearout, Dora; Hu, Shu-Ching; Cholerton, Brenna A; Montine, Thomas J; Edwards, Karen L; Zabetian, Cyrus P

2017-08-01

Cognitive impairment is a common and disabling problem in Parkinson's disease (PD). Identification of genetic variants that influence the presence or severity of cognitive deficits in PD might provide a clearer understanding of the pathophysiology underlying this important nonmotor feature. We genotyped 1105 PD patients from the PD Cognitive Genetics Consortium for 249,336 variants using the NeuroX array. Participants underwent assessments of learning and memory (Hopkins Verbal Learning Test-Revised [HVLT-R]), working memory/executive function (Letter-Number Sequencing and Trail Making Test [TMT] A and B), language processing (semantic and phonemic verbal fluency), visuospatial abilities (Benton Judgment of Line Orientation [JoLO]), and global cognitive function (Montreal Cognitive Assessment). For common variants, we used linear regression to test for association between genotype and cognitive performance with adjustment for important covariates. Rare variants were analyzed using the optimal unified sequence kernel association test. The significance threshold was defined as a false discovery rate-corrected p-value (P FDR ) of 0.05. Eighteen common variants in 13 genomic regions exceeded the significance threshold for one of the cognitive tests. These included GBA rs2230288 (E326K; P FDR  = 2.7 × 10 -4 ) for JoLO, PARP4 rs9318600 (P FDR  = 0.006), and rs9581094 (P FDR  = 0.006) for HVLT-R total recall, and MTCL1 rs34877994 (P FDR  = 0.01) for TMT B-A. Analysis of rare variants did not yield any significant gene regions. We have conducted the first large-scale PD cognitive genetics analysis and nominated several new putative susceptibility genes for cognitive impairment in PD. These results will require replication in independent PD cohorts. Published by Elsevier Inc.

Fluorite Ce0.8Sm0.2O2- δ porous layer coating to enhance the oxygen permeation behavior of a BaCo0.7Fe0.2Nb0.1O3- δ mixed conductor

NASA Astrophysics Data System (ADS)

Wang, Tai-he; Song, Wei-jia; Li, Rong; Zhen, Qiang

2016-06-01

Fluorite Ce0.8Sm0.2O2- δ (SDC) nanopowder with a crystallite size of 15 nm was synthesized by a co-precipitation method. An SDC porous layer was coated onto a BaCo0.7Fe0.2Nb0.1O3- δ (BCFN) mixed conductor to improve its oxygen transport behavior. The results show that the SDC-coated BCFN membrane exhibits a remarkably higher oxygen permeation flux ({J_{{O_2}}}) than the uncoated BCFN in the partial oxidation of coke oven gas (COG). The maximum {J_{{O_2}}} value of the SDC-coated BCFN is 18.28 mL·min-1·cm-2 under a COG/air flux of 177 mL·min-1/353 mL·min-1 at 875°C when the thickness of the BCFN membrane is 1 mm; this {J_{{O_2}}} value is 23% higher than that of the uncoated BCFN membrane. This enhancement is likely because of the higher oxygen ionic conductivity of SDC, which supplies oxygen vacancies and accelerates oxygen exchange on the membrane/coating layer/gas three-phase boundary.

Water relations of coast redwood planted in the semi-arid climate of southern California.

PubMed

Litvak, Elizaveta; McCarthy, Heather R; Pataki, Diane E

2011-08-01

Trees planted in urban landscapes in southern California are often exposed to an unusual combination of high atmospheric evaporative demand and moist soil conditions caused by irrigation. The water relations of species transplanted into these conditions are uncertain. We investigated the water relations of coast redwood (Sequoia sempervirens) planted in the urbanized semi-arid Los Angeles Basin, where it often experiences leaf chlorosis and senescence. We measured the sap flux (J(O)) and hydraulic properties of irrigated trees at three sites in the Los Angeles region. We observed relatively strong stomatal regulation in response to atmospheric vapour pressure deficit (D; J(O) saturated at D < 1 kPa), and a linear response of J(O) to photosynthetically active radiation. Total tree water use by coast redwood was relatively low, with plot-level transpiration rates below 1 mm d(-1) . There was some evidence of xylem cavitation during the summer, which appeared to be reversed in fall and early winter. We conclude that water stress was not a direct factor in causing leaf chlorosis and senescence as has been proposed. Instead, the relatively strong stomatal control that is adaptive in the native habitat of coast redwood may lead to carbon limitation and other stresses in semi-arid, irrigated habitats. © 2011 Blackwell Publishing Ltd.

Paleoenvironmental History of JoCo Marsh, Jamaica Bay, New York

NASA Technical Reports Server (NTRS)

Liberman, Louisa; Peteet, Dorothy; Hansen, James E. (Technical Monitor)

2001-01-01

Sediment cores from JoCo Marsh, located in Jamaica Bay, NY were analyzed for plant macrofossil and foraminifera records. These records reflect changes in vegetation, sea level, climate and human intervention. Better understanding of past environmental changes provides information for future preservation and protection of the estuary. A 2.81 m core was retrieved from JoCo, a high marsh area located on the eastern side of Jamaica Bay. The lithology of the core differs from high levels of sand, with small amounts of clay, in the bottom 0.8 meters, to salt marsh peat in the upper 2 meters of the core. Basal wood in the sand was dated to about 2060 yr BP. Elphidium foraminifera dominate the basal sands, along with Scirpus seeds, wood, and charcoal. These sands include fish scales which are tentatively identified as killifish, suggesting shallow pools. The transition to marsh peat is dominated by sedge seeds, and declines in charcoal. The peat appears to be dominated by salt marsh grasses. At 2 m the foraminifera change to include mainly Trochammina species and other undifferentiated agglutinates. The upper portion of the core is dominated by Salicornia seeds along with Trochammina and Miliammina or Quinqueloculia. The history of this marsh will be integrated with other records of marsh environmental change along the US eastern seaboard.

Spectral investigations of Sm{sup 3+}-doped oxyfluorosilicate glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramachari, D.; Rama Moorthy, L., E-mail: lrmphysics@yahoo.co.in; Department of Physics, Chadalawada Ramanamma Engineering College, Renigunta Road, Tirupati 517506

2013-09-01

Graphical abstract: The figure shows the emission spectra of Sm{sup 3+} doped KNSZL glass for different concentrations. Among the four emission transitions {sup 4}G{sub 5/2} → {sup 6}H{sub 5/2}, {sup 4}G{sub 5/2} → {sup 6}H{sub 7/2}, {sup 4}G{sub 5/2} → {sup 6}H{sub 9/2} and {sup 4}G{sub 5/2} → {sup 6}H{sub 11/2}, the {sup 4}G{sub 5/2} → {sup 6}H{sub 7/2} transition of KNSZLSm10 glass is more intense compared with all the transitions. The insert figure shows, the color coordinates (0.59, 0.41) of KNSZLSm10 glass is located on the perimeter of the chromaticity diagram at 592 nm which appears to be closestmore » to the orange color. From these results the KNSZLSm10 glass could be useful for optical amplifiers, waveguides, telecommunications and orange LEDs. - Highlights: • From the DTA, the undoped KNSZL glass more precisely in fiberdrawing. • The XRD pattern confirmed the KNbO{sub 3} nanocrystallites of undoped KNSZL glass. • FTIR and Raman data of KNSZLSm10 glass revealed structural properties. • Judd–Ofelt analysis and decay measurements were carried out. • The optical gain parameter of the investigated glass is 18.13 × 10{sup −25} cm{sup 2} s. - Abstract: Sm{sub 2}O{sub 3}-doped oxyfluorosilicate glasses were prepared by melt-quenching method. The differential thermal analysis and X-ray diffraction were carried out to investigate the glass transition temperature and structure of precursor glass. Infrared spectroscopy, Raman, optical absorption, photoluminescence and decay measurements were carried out for Sm{sup 3+}-doped oxyfluorosilicate glasses. From the absorption spectrum, the Judd–Ofelt intensity parameters have been evaluated to predict the radiative properties for the emission levels of Sm{sup 3+} ions. The lifetimes of {sup 4}G{sub 5/2} level are found to decrease from 1.17 to 0.93 ms due to the energy transfer, when the concentration of Sm{sup 3+} ions increases from 0.1 to 2.0 mol%. The optical gain parameter (18.13 × 10{sup −25} cm{sup 2} s) of the investigated glass is found to be higher than the other Sm{sub 2}O{sub 3}-doped glass systems.« less

Spin-lattice relaxation of coupled metal-radical spin-dimers in proteins: application to Fe(2+)-cofactor (Q(A)(-.), Q(B)(-.), phi(-.)) dimers in reaction centers from photosynthetic bacteria.

PubMed Central

Calvo, Rafael; Isaacson, Roger A; Abresch, Edward C; Okamura, Melvin Y; Feher, George

2002-01-01

The spin-lattice relaxation times (T(1)) for the reduced quinone acceptors Q(A)(-.) and Q(B)(-.), and the intermediate pheophytin acceptor phi(-.), were measured in native photosynthetic reaction centers (RC) containing a high spin Fe(2+) (S = 2) and in RCs in which Fe(2+) was replaced by diamagnetic Zn(2+). From these data, the contribution of the Fe(2+) to the spin-lattice relaxation of the cofactors was determined. To relate the spin-lattice relaxation rate to the spin-spin interaction between the Fe(2+) and the cofactors, we developed a spin-dimer model that takes into account the zero field splitting and the rhombicity of the Fe(2+) ion. The relaxation mechanism of the spin-dimer involves a two-phonon process that couples the fast relaxing Fe(2+) spin to the cofactor spin. The process is analogous to the one proposed by R. Orbach (Proc. R. Soc. A. (Lond.). 264:458-484) for rare earth ions. The spin-spin interactions are, in general, composed of exchange and dipolar contributions. For the spin dimers studied in this work the exchange interaction, J(o), is predominant. The values of J(o) for Q(A)(-.)Fe(2+), Q(B)(-.)Fe(2+), and phi(-.)Fe(2+) were determined to be (in kelvin) -0.58, -0.92, and -1.3 x 10(-3), respectively. The |J(o)| of the various cofactors (obtained in this work and those of others) could be fitted with the relation exp(-beta(J)d), where d is the distance between cofactor spins and beta(J) had a value of (0.66-0.86) A(-1). The relation between J(o) and the matrix element |V(ij)|(2) involved in electron transfer rates is discussed. PMID:12414679

Evaluation of Neuroprotection and Behavioral Recovery by the Kappa- Opioid, PD 117302 Following Transient Forebrain Ischemia

DTIC Science & Technology

1994-01-01

shown to protect against NMDA -induced convul- mate- and aspartate-stimulated NMDA activity mediates delayed sions in rats (38), and to reduce...assessing a variety of pharmacological and physiological manip- competitive NMDA antagonists have been shown to decrease ulations (e.g., 40). Additionally...Hayward, N. J.; Tyers, 8. DeLong, G. R. Autism , amnesia, hippocampus, and learning. Neu- M. B.; Scopes, D. 1. C.; Naylor, A.; Judd, D. B. Neuroprotective

Energy Behavior Change and Army Net Zero Energy; Gaps in the Army’s Approach to Changing Energy Behavior

DTIC Science & Technology

2014-06-13

age, and design , installations set benchmarks for utility use and cost. This benchmark includes a buffer above and below the baseline. If residents...sustainability officers from each government agency (US President 2009, 6). The order requires that each federal agency designate a senior...conducting direct comparisons of pre and post intervention data (Judd et al. 2013, 15). Soldiers were the primary occupants of the three buildings with

[Deforestation in the state of Mato Grosso in the book Journey around Brazil 1875-1878, by the doctor João Severiano da Fonseca].

PubMed

Ferraro, Mário Roberto; Figueirôa, Silvia Fernanda de Mendonça

2017-01-01

This presents reflections on scientific production issued by the Commission for the Demarcation of the Empire's Border Limits with Bolivia, with a focus on the environmental destruction of Mato Grosso state, as reported in João Severiano da Fonseca's book, Journey around Brazil 1875-1878. Fonseca reported severe deforestation on the banks of the river Paraguay and advocated for protectionist measures from the state government. He set out a vision for Mato Grosso's development that involved better use of the state's natural resources, raw materials exports, and regional industrialization support. The methodology created an interface between environmental history and history of the sciences.

A case of non-specific interstitial pneumonia with recurrent gastric carcinoma and anti-Jo-1 antibody positive myositis.

PubMed

Ebisutani, Chikara; Ito, Isao; Kitaichi, Masanori; Tanabe, Naoya; Mishima, Michiaki; Kadowaki, Seizo

2016-07-01

We report the first case of non-specific interstitial pneumonia (NSIP) in a patient with cancer-associated myositis (CAM) that emerged along with the recurrence of the cancer. A 60-year-old woman, with a history of partial gastrectomy for gastric cancer 11 years ago, presented with exertional dyspnea with anti-Jo-1 antibody-positive myositis. Surgical lung biopsy showed NSIP with metastatic gastric cancer. Accordingly, her condition was diagnosed as CAM with cancer recurrence. In patients with a history of cancer, development of myositis may indicate cancer recurrence; therefore, careful observation would be necessary. Copyright © 2016 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.

Limited Surface Observations Climatic Summaries for Avon Park, Florida, MSC 747960. Parts A thru F

DTIC Science & Technology

1987-02-01

N -aa cm .c 2. C. a b- IAD C ’a. la U U. o I It. CD = MEM 040 0 0) 543. 0 ’Cc 0$4 (a> 0 0t I 0.jO 0 04.0 0 00 0 Ř 4V JO 0 4) U (da. 0 .4 ’ ,0 VO...00 V3 00 0; 0; C P. 0%; Z>0 0 0 OD in In 0% 0 co in IA -C p4 __ 0 4n > 0. 0 >- 0f do 0 -4 0 0y aUJ ~ a M. CPh ohp oh6 0l 0 0- 09 z z Cl U cl 0 an

A Transformation Yielding an Additive Representation of Data in a Two-Way Array.

DTIC Science & Technology

1980-08-15

Psychological Association 1200 17th Street N.W. 1 Dr. Gary Marco Washington, DC 20036 Educational Testing Service Princeton, NJ 08450 Dr. Wilson A. Judd...ADA,11 b6b PORTLAND STATE UNIV OR DEPT OF PSYCHOLOGY F/G 12/1 A TRANSFORMATION YILLDING AN ADDITIVE REPRESENTATION OF DATA IN--ETC(U) AUG bO J A PAUL...DATA IN A TWO-WAY ARRAY James A. Paulson Psychology Department Portland State University Approved for public release; distribution unlimited

Experiment on the Effects of Storage Duration of Biodiesel produced from Crude Palm Oil, Waste Cooking oil and Jatropha

NASA Astrophysics Data System (ADS)

Nanihar, Nadiarulah; Khalid, Amir; Mustaffa, Norrizal; Jaat, Norrizam; Sapit, Azwan; Razali, Azahari; Sunar, Norshuhaila Mohamed

2017-10-01

Biodiesel based on vegetable oil is an alternative that had various advantage in term of sustainability and environmental attractive compare to others conventional diesel. Biodiesel is product of any fat or oil that derived from any organic sources through a refinery process called transesterification process. This research investigates the effects of storage duration and variant ambient condition on the biodiesel properties and characteristics. In this study, there are three types of blending which is 5vol% blends ( 5vol% plant oil 95vol% diesel), 10vol% blending (10vol% plant oil and 90vol% diesel) and 15vol% blending (15vol% plant oil and 85vol% diesel) each called CPO5 (crude palm oil 5vol%), CPO10 (crude palm oil 10vol%),CPO15 (crude palm oil 15vol%), JO5 (jatropha oil 5vol%), JO10 (jatropha oil 10vol%),and JO15 (jatropha oil 15vol%) respectively. Biodiesel samples were stored at indoor condition and outdoor condition for a 3 months period. The fuel properties such as acid value, viscosity, density, water content and flash point are observed with the laboratory instrument. Flash point value and water content increased under both of indoor and outdoor condition and a steady data for viscosity and density. However, acid value at indoor condition nearly constant but increased dramatically for outdoor condition over the time.

Editorial: Introduction to the Special Section on Causal Inference in Cross Sectional and Longitudinal Mediational Models

PubMed Central

West, Stephen G.

2016-01-01

Psychologists have long had interest in the processes through which antecedent variables produce their effects on the outcomes of ultimate interest (e.g., Wood-worth's Stimulus-Organism-Response model). Models involving such meditational processes have characterized many of the important psychological theories of the 20th century and continue to the present day. However, it was not until Judd and Kenny (1981) and Baron and Kenny (1986) combined ideas from experimental design and structural equation modeling that statistical methods for directly testing such models, now known as mediation analysis, began to be developed. Methodologists have improved these statistical methods, developing new, more efficient estimators for mediated effects. They have also extended mediation analysis to multilevel data structures, models involving multiple mediators, models in which interactions occur, and an array of noncontinuous outcome measures (see MacKinnon, 2008). This work nicely maps on to key questions of applied researchers and has led to an outpouring of research testing meditational models (As of August, 2011, Baron and Kenny's article has had over 24,000 citations according to Google Scholar). PMID:26736046

Serosurveillance of Scrub Typhus in Small Mammals Collected from Military Training Sites near the DMZ, Northern Gyeonggi-do, Korea, and Analysis of the Relative Abundance of Chiggers from Mammals Examined

DTIC Science & Technology

2010-09-01

Korean J Paras/to/. Vol. 48, No. 3: 237-243, September 2010 DOl: JO.J3471kjp.2010.48.J.237 Serosurveillance of Scrub Typhus in Small Mammals...65th Medical BrigadeAJSAMEDDAC-Korea, Unit# 15281, APO AP 96205-5281, USA Abstract: Comprehensive quarterly serosurveillance on scrub typhus in small...rarely observed (prevalence < 1 0%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4

Analysis of four dental alloys following torch/centrifugal and induction/ vacuum-pressure casting procedures.

PubMed

Thompson, Geoffrey A; Luo, Qing; Hefti, Arthur

2013-12-01

Previous studies have shown casting methodology to influence the as-cast properties of dental casting alloys. It is important to consider clinically important mechanical properties so that the influence of casting can be clarified. The purpose of this study was to evaluate how torch/centrifugal and inductively cast and vacuum-pressure casting machines may affect the castability, microhardness, chemical composition, and microstructure of 2 high noble, 1 noble, and 1 base metal dental casting alloys. Two commonly used methods for casting were selected for comparison: torch/centrifugal casting and inductively heated/ vacuum-pressure casting. One hundred and twenty castability patterns were fabricated and divided into 8 groups. Four groups were torch/centrifugally cast in Olympia (O), Jelenko O (JO), Genesis II (G), and Liberty (L) alloys. Similarly, 4 groups were cast in O, JO, G, and L by an inductively induction/vacuum-pressure casting machine. Each specimen was evaluated for casting completeness to determine a castability value, while porosity was determined by standard x-ray techniques. Each group was metallographically prepared for further evaluation that included chemical composition, Vickers microhardness, and grain analysis of microstructure. Two-way ANOVA was used to determine significant differences among the main effects. Statistically significant effects were examined further with the Tukey HSD procedure for multiple comparisons. Data obtained from the castability experiments were non-normal and the variances were unequal. They were analyzed statistically with the Kruskal-Wallis rank sum test. Significant results were further investigated statistically with the Steel-Dwass method for multiple comparisons (α=.05). The alloy type had a significant effect on surface microhardness (P<.001). In contrast, the technique used for casting did not affect the microhardness of the test specimen (P=.465). Similarly, the interaction between the alloy and casting technique was not significant (P=.119). A high level of castability (98.5% on average) was achieved overall. The frequency of casting failures as a function of alloy type and casting method was determined. Failure was defined as a castability index score of <100%. Three of 28 possible comparisons between alloy and casting combinations were statistically significant. The results suggested that casting technique affects the castability index of alloys. Radiographic analysis detected large porosities in regions near the edge of the castability pattern and infrequently adjacent to noncast segments. All castings acquired traces of elements found in the casting crucibles. The grain size for each dental casting alloy was generally finer for specimens produced by the induction/vacuum-pressure method. The difference was substantial for JO and L. This study demonstrated a relation between casting techniques and some physical properties of metal ceramic casting alloys. Copyright © 2013 Editorial Council for the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

GASP. V. Ram-pressure stripping of a ring Hoag's-like galaxy in a massive cluster

NASA Astrophysics Data System (ADS)

Moretti, A.; Poggianti, B. M.; Gullieuszik, M.; Mapelli, M.; Jaffé, Y. L.; Fritz, J.; Biviano, A.; Fasano, G.; Bettoni, D.; Vulcani, B.; D'Onofrio, M.

2018-04-01

Through an ongoing MUSE program dedicated to study gas removal processes in galaxies (GAs Stripping Phenomena in galaxies with MUSE, GASP), we have obtained deep and wide integral field spectroscopy of the galaxy JO171. This galaxy resembles the Hoag's galaxy, one of the most spectacular examples of ring galaxies, characterized by a completely detached ring of young stars surrounding a central old spheroid. At odds with the isolated Hoag's galaxy, JO171 is part of a dense environment, the cluster Abell 3667, which is causing gas stripping along tentacles. Moreover, its ring counter-rotates with respect to the central spheroid. The joint analysis of the stellar populations and the gas/stellar kinematics shows that the origin of the ring was not due to an internal mechanism, but was related to a gas accretion event that happened in the distant past, prior to accretion on to Abell 3667, most probably within a filament. More recently, since infall in the cluster, the gas in the ring has been stripped by ram pressure, causing the quenching of star formation in the stripped half of the ring. This is the first observed case of ram-pressure stripping in action in a ring galaxy, and MUSE observations are able to reveal both of the events (accretion and stripping) that caused dramatic transformations in this galaxy.

Actinometric measurements and theoretical calculations of j/O3/, the rate of photolysis of ozone to O/1D/

NASA Technical Reports Server (NTRS)

Dickerson, R. R.; Stedman, D. H.; Chameides, W. L.; Crutzen, P. J.; Fishman, J.

1979-01-01

The paper presents an experimental technique which measures j/O3-O(1-D)/, the rate of solar photolysis of ozone to singlet oxygen atoms. It is shown that a flow actinometer carries dilute O3 in N2O into direct sunlight where the O(1D) formed reacts with N2O to form NO which chemiluminescence detects, with a time resolution of about one minute. Measurements indicate a photolysis rate of 1.2 (+ or - .2) x 10 to the -5/s for a cloudless sky, 45 deg zenith angle, 0.345 cm ozone column and zero albedo. Finally, ground level results compare with theoretical calculations based on the UV actinic flux as a function of ozone column and solar zenith angle.

Biomedical hypothesis generation by text mining and gene prioritization.

PubMed

Petric, Ingrid; Ligeti, Balazs; Gyorffy, Balazs; Pongor, Sandor

2014-01-01

Text mining methods can facilitate the generation of biomedical hypotheses by suggesting novel associations between diseases and genes. Previously, we developed a rare-term model called RaJoLink (Petric et al, J. Biomed. Inform. 42(2): 219-227, 2009) in which hypotheses are formulated on the basis of terms rarely associated with a target domain. Since many current medical hypotheses are formulated in terms of molecular entities and molecular mechanisms, here we extend the methodology to proteins and genes, using a standardized vocabulary as well as a gene/protein network model. The proposed enhanced RaJoLink rare-term model combines text mining and gene prioritization approaches. Its utility is illustrated by finding known as well as potential gene-disease associations in ovarian cancer using MEDLINE abstracts and the STRING database.

Evidence of a conserved role for Chlamydia HtrA in the replication phase of the chlamydial developmental cycle.

PubMed

Patel, Pooja; De Boer, Leonore; Timms, Peter; Huston, Wilhelmina May

2014-08-01

Identification of the HtrA inhibitor JO146 previously enabled us to demonstrate an essential function for HtrA during the mid-replicative phase of the Chlamydia trachomatis developmental cycle. Here we extend our investigations to other members of the Chlamydia genus. C. trachomatis isolates with distinct replicative phase growth kinetics showed significant loss of viable infectious progeny after HtrA was inhibited during the replicative phase. Mid-replicative phase addition of JO146 was also significantly detrimental to Chlamydia pecorum, Chlamydia suis and Chlamydia cavie. These data combined indicate that HtrA has a conserved critical role during the replicative phase of the chlamydial developmental cycle. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Immunotherapy: questions to ask your doctor

MedlinePlus

... Schroeder H, Frew AJ, Weyand CM, eds. Clinical Immunology . 4th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 77. Pardoll D. Cancer immunology. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan ...

[Silva Coutinho: his career and his contributions to the geological collections of the Museu Nacional in Rio de Janeiro].

PubMed

Silva, Marina Jardim E; Fernandes, Antonio Carlos Sequeira; Fonseca, Vera Maria Medina da

2013-06-01

The career of João Martins da Silva Coutinho is linked to the history of the Museu Nacional in Rio de Janeiro to whose collections (especially geological) he contributed scientific information and material. On the Brazilian scientific stage, Silva Coutinho took part in major exploratory commissions in the latter half of the nineteenth century, mainly in the Amazon and in the Northeast. He collected and sent samples to the Museu Nacional for analysis, establishing deep ties with the institution and its staff. The article presents his contributions through an analysis of these documents and an examination of the geological collections that he sent to the institution and that remain part of its holdings.

Immunotherapy for cancer

MedlinePlus

... 2017. Accessed February 15, 2018. Pardoll D. Cancer immunology. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan ... D.A.M. Editorial team. Related MedlinePlus Health Topics Cancer Immunotherapy Browse the Encyclopedia A.D.A. ...

Genetics Home Reference: FG syndrome

MedlinePlus

... inheritance is that fathers cannot pass X-linked traits to their sons. Related Information What does it ... Opitz JO. Behavior phenotype of FG syndrome: cognition, personality, and behavior in eleven affected boys. Am J ...

Putting Science FIRST: Memories of Family Science Experiences.

ERIC Educational Resources Information Center

Science and Children, 1996

1996-01-01

Presents anecdotes from prominent citizens including Bill Clinton, Alan Alda, Carl Sagan, Gerald Wheeler, JoAnne Vasquez, and Lynn Margulis in which they reminisce about interesting science experiences with their families. (JRH)

Vulva cancer

MedlinePlus

Jhingran A, Russell AH, Seiden MV, et al. Cancers of the cervix, vulva, and vagina. In: Niederhuber JE, Armitage JO, Doroshow ... Updated January 31, 2018. Accessed March 9, 2018. Russell AH, Horowitz NS. Cancers of the vulva and ...

A Mathematical Model for the Starting Process of a Transonic Ludwieg Tube Wind Tunnel

DTIC Science & Technology

1976-06-01

8217\\J.; tD ~f\\Jo"~ .... ..n 1"")’\\1 >0 ..... ~,..,::?o3’ ..o~(JI. .... ", · ... . OO~OO _oo_.n 00000 , " 00000 0..,...,’\\1 ..... 0""- 0> fi’) .0...0.2961b8D 00 0.91> ..... bbD Ul O.220JO:’LJ 02 0.4861b80 03 U.’>1l4b:’OO 03 O,"b4bJI:IO uJ .~ 0 0’’�)80 U3 OolO8246!)-O! 0.10710:>0-01 0...34i) .NE • .lto_D.O_lGn ... TD _lL_. ______ . ___ ~ N:? ____ ._. ___ .1 f. . .l2BE A L (I>H I ~E..’..10u.u.D,-,Qu)..lOG!.’.<QL-LT-"Q,---Ŗ_,,O

Health assessment for Lake Sandy Jo Landfill, Gary, Indiana, Region 5. CERCLIS No. IND980500524. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1985-11-21

The 50-acre Lake Sandy Jo Landfill is located in the Black Oak community (predominantly residential) of southwestern Gary in Lake County, Indiana. From about 1971 until about 1980, the lake was filled in with construction and demolition debris, municipal garbage, industrial wastes, hazardous materials, and possibly drummed wastes. These wastes are partly to completely exposed on the landfill surface. Surface soil, subsurface soil, surface water, sediment, and ground water show a variety of metal and organic chemical carcinogens. Toxic noncarcinogen priority pollutants found were chloromethane, copper, cyanide, lead, mercury, and silver. Inorganic soil levels found on the site for leadmore » and cadmium exceed levels of concern that would permit unrestricted use of the site. Remedial measures would be necessary before the site could be granted unrestricted use.« less

Solid State Physics. Nitrogen Adsorption by Thermoexfoliated Graphite / Slāpekļa Adsorbcija Uz Termoeksfoliētā Grafīta

NASA Astrophysics Data System (ADS)

Grehov, V.; Kalnacs, J.; Matzui, L.; Knite, M.; Murashov, A.; Vilken, A.

2013-02-01

Adsorption by thermochemically exfoliated graphite (TEG) is studied and compared with that by other carbon structures under the same conditions. In BET determination of the specific surface area (SBET) for the TEG samples it was found that good approximation could be observed in two different pressure ranges. Such ranges of BET approximation are also visible in the isotherms of aquadag and milled graphite. The experimental results are discussed and their interpretation proposed Ar sorbcijas iekārtu Autosorb-1 (Quantochrome Instruments Co, Florida, USA) pētīta termiski eksfoliēta grafīta slāpekļa sorbcijas spēja salīdzinājumā ar citu oglekļa struktūru sorbciju tādos pašos apstākļos. Atrasti divi izotermu rajoni, kas raksturojas ar mazu (SBET1) un palielinātu (SBET2) īpatnējo virsmu.. Šāda veida izotermas raksturīgas slikti adsorbējošiem materiāliem, pie kādiem pieder arī akvadags. Labi adsorbējošās oglekļa struktūrām, tādām kā aktīvā ogle un oglekļa nanocaurules, raksturīgas cita veida izotermas. Apspriesta eksperimentālā rezultāta interpretācija

Action principle for Coulomb collisions in plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirvijoki, Eero

In this study, an action principle for Coulomb collisions in plasmas is proposed. Although no natural Lagrangian exists for the Landau-Fokker-Planck equation, an Eulerian variational formulation is found considering the system of partial differential equations that couple the distribution function and the Rosenbluth-MacDonald-Judd potentials. Conservation laws are derived after generalizing the energy-momentum stress tensor for second order Lagrangians and, in the case of a test-particle population in a given plasma background, the action principle is shown to correspond to the Langevin equation for individual particles.

Differential formulation of the gyrokinetic Landau operator

DOE PAGES

Hirvijoki, Eero; Brizard, Alain J.; Pfefferlé, David

2017-01-05

Subsequent to the recent rigorous derivation of an energetically consistent gyrokinetic collision operator in the so-called Landau representation, this work investigates the possibility of finding a differential formulation of the gyrokinetic Landau collision operator. It is observed that, while a differential formulation is possible in the gyrokinetic phase space, reduction of the resulting system of partial differential equations to five dimensions via gyroaveraging poses a challenge. Finally, based on the present work, it is likely that the gyrocentre analogues of the Rosenbluth–MacDonald–Judd potential functions must be kept gyroangle dependent.

Action principle for Coulomb collisions in plasmas

DOE PAGES

Hirvijoki, Eero

2016-09-14

In this study, an action principle for Coulomb collisions in plasmas is proposed. Although no natural Lagrangian exists for the Landau-Fokker-Planck equation, an Eulerian variational formulation is found considering the system of partial differential equations that couple the distribution function and the Rosenbluth-MacDonald-Judd potentials. Conservation laws are derived after generalizing the energy-momentum stress tensor for second order Lagrangians and, in the case of a test-particle population in a given plasma background, the action principle is shown to correspond to the Langevin equation for individual particles.

Characterization and origin of spongillite-hosting sediment from João Pinheiro, Minas Gerais, Brazil

NASA Astrophysics Data System (ADS)

Almeida, A. C. S.; Varajão, A. F. D. C.; Gomes, N. S.; Varajão, C. A. C.; Volkmer-Ribeiro, C.

2010-03-01

Spongillite from João Pinheiro, Minas Gerais, Brazil is mainly known for its use in brick production and in the refractory industry. Very few studies have focused on its geological context. Spongillite-rich deposits occur in shallow ponds on a karstic planation surface developed on rocks of the Neoproterozoic São Francisco Supergroup. Cenozoic siliciclastic sediments are related to this surface. A field study of these deposits and analysis of multispectral images showed a SE-NW preferential drainage system at SE, suggesting that Mesozoic Areado Group sandstones were the source area of the spongillite-hosting sediments. Mineralogical and textural characterization by optical microscopic analysis, X-ray diffraction (XRD), differential and gravimetric thermal analysis (DTA-GTA), infrared spectroscopy (IR) and scanning electron microscopy (SEM) of seven open-pit spongillite-rich deposits (Avião, Carvoeiro, Vânio, Preguiça, Divisa, Severino, Feijão) showed a sedimentological similarity between the deposits. They are lens-shaped and are characterized at the bottom by sand facies, in the middle by spicules-rich muddy-sand facies and at the top by organic matter-rich muddy-sand facies. Petrographically, the spongillite-hosting sediments and the siliclastic sediments of the Areado Group show detrital phases with similar mineralogical and textural features, such as the presence of well-sorted quartz grains and surface features of abrasion typical of aeolian reworking that occurred in the depositional environment in which the sandstones of the Areado Group were formed. Detrital heavy minerals, such as staurolite, zircon, tourmaline, and clay minerals, such as kaolinite, low amounts of illite, scarce chlorite and mixed-layer chlorite/smectite and illite/smectite occur in the spongillite-hosting sediments and in sandstones from the Areado Group. In both formations, staurolite has similar chemical composition. These mineralogical and textural features show that the sediments of the Areado Group constitute the main source of the pond sediments that host spongillite.

Fat stigma and public health: a theoretical framework and ethical analysis.

PubMed

Abu-Odeh, Desiree

2014-09-01

This paper proposes a theoretical framework for understanding fat stigma and its impact on people's well-being. It argues that stigma should never be used as a tool to achieve public health ends. Drawing on Bruce Link and Jo Phelan's 2001 conceptualization of stigma as well as the works of Hilde Lindemann, Paul Benson, and Margaret Urban Walker on identity, positionality, and agency, this paper clarifies the mechanisms by which stigmatizing, oppressive conceptions of overweight and obesity damage identities and diminish moral agency, arguing that the use of obesity-related stigma for public health ends violates the bioethics principles of nonmaleficence, autonomy, and justice.

76 FR 11507 - National Register of Historic Places; Notification of Pending Nominations and Related Actions

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-02

... Increase), 3545 Williamsburg Ln N.W., Washington, 11000071 HAWAII Hawaii County Henderson, Walter Irving... SW J.O. West Rd, Scappoose, 11000049 VIRGINIA Danville Independent City Schoolfield Welfare Building...

Brazil opens its first private research institute

NASA Astrophysics Data System (ADS)

Ivanissevich, Alicia

2017-05-01

The Brazilian filmmaker João Moreira Salles - whose family owns one of the largest banks in Brazil - has established a new institute in Rio de Janeiro that will support basic research across all sciences.

Pituitary tumor

MedlinePlus

... during the person's lifetime. The pituitary is part of the endocrine system. The pituitary helps control the release of hormones ... Hollander AB, Alonso-Basanta M, et al. Cancer of the central nervous system. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan ...

Paleomagnetic and mineral magnetic constraints on Zn-Pb ore genesis in the Pend Oreille Mine, Metaline district, Washington, USA

USGS Publications Warehouse

Pannalal, S.J.; Symons, David T. A.; Leach, D.L.

2007-01-01

Zinc-lead mineralization in the Metaline mining district of northeastern Washington, USA, is hosted by the Cambrian Metaline Formation and is classified into Yellowhead-type (YO) and Josephine-type (JO) ore based on texture and mineralogy. Paleomagnetic results are reported for four Cambrian Metaline Formation sites, one Ordovician Ledbetter slate site, 12 YO and 13 JO (including two breccia sites) mineralization sites in the Pend Oreille Mine, and eight sites from the nearby Cretaceous Kaniksu granite batholith. Thermal and alternating field step demagnetization, saturation isothermal remanence analysis, and synthetic specimen tests show that the remanence in the host carbonates and Zn-Pb mineralization is carried mostly by pseudosingle (PSD) to single domain (SD) pyrrhotite and mostly by PSD to SD magnetite in the Kaniksu granite. Based on thermomagnetic measurements, sphalerite and galena concentrates and tailings from the mine's mill contain hexagonal and monoclimc pyrrhotite. The postfolding characteristic remanent magnetization (ChRM), known thermal data, and paleoarc method of dating suggest that the Zn-Pb mineralization carries a primary chemical remanent magnetization (CRM), and Metaline Formation carbonates a secondary CRM that were acquired during the Middle Jurassic (166 ??6 Ma) during the waning stages of the Nevadan orogeny. A paleomagnetic breccia test favours a solution-collapse origin for the Josephine breccia. Finally, the Kaniksu paleopole is concordant with the North American Cretaceous reference paleopole, suggesting the Kootenay terrane has not been rotated since emplacement of the batholith at ???94 Ma. ?? 2007 NRC Canada.

Analysis of the Appendicularia class (subphylum Urochordata) as a possible tool for biomonitoring four estuaries of the tropical region.

PubMed

de Carvalho, Pedro Freitas; Bonecker, Sérgio Luiz Costa; Nassar, Cristina Aparecida Gomes

2016-11-01

This study aims to characterize the differences between physical and chemical parameters of water quality indicators and eutrophication in four estuaries of the state of Rio de Janeiro and relate them to full density of the species that belong to the Appendicularia class with the purpose of seeking bioindicators for estuarine areas. The estuaries studied were from the rivers Macaé, São João, Bracuí, and Perequê-Açu. The physicochemical parameters monitored for evaluation of the water bodies and used for the correlation with the appendicularians were pH, temperature, nitrite, nitrate, N-ammonia, total nitrogen, phosphate, total phosphorus, dissolved oxygen (DO), suspended particulate matter (SPM), chlorophyll a, heterotrophic bacteria, and fecal coliform. The estuaries Bracuí and São João showed enhanced qualities of water and lower degrees of eutrophication than Macae and Perequê-Açu estuaries. The species of the Appendicularia class found in this study were Oikopleura longicauda (Vogt, 1854), Oikopleura dioica Fol, 1872, Oikopleura fusiformis Fol, 1872, and Fritillaria haplostoma Fol, 1872. The density of appendicularians and O. longicauda was inversely related to the nutrient values and SPM; nonetheless, no species of appendicularians could be used as a bioindicator of any estuary in the current study. Studies on the quality of estuary waters and the search for other bioindicators belonging to other zooplankton groups are recommended to confirm the obtained results and to expand the knowledge of these coastal environments.

75 FR 27616 - Qualification of Drivers; Exemption Applications; Diabetes Mellitus

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-17

... L. Brokaw, Chris D. Chambers, Charles A. Cinert, Sr., John D. Clark, IV, Dale J. Cleaver, James H..., Robert W. Prabucki, Edward R. Ramm, Wayne F. Richards, George H. Rollins, Jo Ellen Roshak, Gary G...

1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #12 EARLY RED BRICK HOUSE, Elk and Prospect Sts., Galena, Illinois - Galena Doorways, Red Brick House, Elk & Prospect Streets, Galena, Jo Daviess County, IL

77 FR 49799 - Medicare and Medicaid Programs; Quarterly Listing of Program Issuances-April Through June 2012

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-17

...-Approved Lung JoAnna Baldwin, MS.. (410) 786-7205 Volume Reduction Surgery Facilities. XIV Medicare-Approved Kate Tillman, RN, (410) 786-9252 Bariatric Surgery MAS. Facilities. XV Fluorodeoxyglucose Stuart...

77 FR 29648 - Medicare and Medicaid Programs; Quarterly Listing of Program Issuances-January Through March 2012

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-18

... (Destination Therapy) Facilities. XIII Medicare-Approved Lung Volume Reduction Surgery JoAnna Baldwin, MS (410) 786-7205 Facilities. XIV Medicare-Approved Bariatric Surgery Facilities........ Kate Tillman, RN, MAS...

76 FR 68467 - Medicare and Medicaid Programs; Quarterly Listing of Program Issuances-April Through June 2011

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-04

...-Approved Lung JoAnna Baldwin, (410) 786-7205 Volume Reduction Surgery MS. Facilities. XIV Medicare-Approved Kate Tillman, RN, (410) 786-9252 Bariatric Surgery Facilities. MAS. XV Fluorodeoxyglucose Positron...

KENNEDY SPACE CENTER, FLA. - KSC External Relations and Business Development Director JoAnn Morgan speaks to attendees of The Florida Commission on the Status of Women held June 7 at the Debus Conference Facility. Morgan is a member of the group’s Hall of Fame. The commission, through coordinating, researching, communicating, and encouraging legislation, is dedicated to empowering women from all walks of life in achieving their fullest potential, to eliminating barriers to that achievement, and to recognizing women’s accomplishments.

NASA Image and Video Library

2003-06-07

KENNEDY SPACE CENTER, FLA. - KSC External Relations and Business Development Director JoAnn Morgan speaks to attendees of The Florida Commission on the Status of Women held June 7 at the Debus Conference Facility. Morgan is a member of the group’s Hall of Fame. The commission, through coordinating, researching, communicating, and encouraging legislation, is dedicated to empowering women from all walks of life in achieving their fullest potential, to eliminating barriers to that achievement, and to recognizing women’s accomplishments.

Molybdenum Valence in Basaltic Silicate Melts

NASA Technical Reports Server (NTRS)

Danielson, L. R.; Righter, K.; Newville, M.; Sutton, S.; Pando, K.

2010-01-01

The moderately siderophile element molybdenum has been used as an indicator in planetary differentiation processes, and is particularly relevant to core formation [for example, 1-6]. However, models that apply experimental data to an equilibrium differentiation scenario infer the oxidation state of molybdenum from solubility data or from multivariable coefficients from metal-silicate partitioning data [1,3,7]. Partitioning behavior of molybdenum, a multivalent element with a transition near the J02 of interest for core formation (IW-2) will be sensitive to changes in JO2 of the system and silicate melt structure. In a silicate melt, Mo can occur in either 4+ or 6+ valence state, and Mo6+ can be either octahedrally or tetrahedrally coordinated. Here we present first XANES measurements of Mo valence in basaltic run products at a range of P, T, and JO2 and further quantify the valence transition of Mo.

[Mental health of college students: experience of the university psychiatric outpatient clinic of Hospital de São João].

PubMed

Silveira, Celeste; Norton, Andreia; Brandão, Isabel; Roma-Torres, António

2011-12-01

The mental health of college students has been raising major awareness, due to the increased prevalence and severity of psychiatric disorders in this population. Higher education is associated with significant stressors that contribute to the development of mental health disturbances, and most college students are in the high-risk age group for the emergence of symptoms of major psychiatric disorders. Early diagnosis and treatment of these disorders in college students are important areas of effort, since they pose a high impact at the educational, economic, and social levels. Thus, specifically planned mental health services play a major role in the management of this population, should be specialized and have easy accessibility. The purpose of this study is to describe and characterize the College Students' psychiatric outpatient clinic of the Department of Psychiatry, Hospital de São João.

Novel RAD sequence data reveal a lack of genomic divergence between dietary ecotypes in a landlocked salmonid population

USGS Publications Warehouse

Limborg, Morten T.; Larson, Wesley; Shedd, Kyle; Seeb, Lisa W.; Seeb, James E.

2017-01-01

Preservation of heritable ecological diversity within species and populations is a key challenge for managing natural resources and wild populations. Salmonid fish are iconic and socio-economically important species for commercial, aquaculture, and recreational fisheries across the globe. Many salmonids are known to exhibit ecological divergence within species, including distinct feeding ecotypes within the same lakes. Here we used 5559 SNPs, derived from RAD sequencing, to perform population genetic comparisons between two dietary ecotypes of sockeye salmon (Oncorhynchus nerka) in Jo-Jo Lake, Alaska (USA). We tested the standing hypothesis that these two ecotypes are currently diverging as a result of adaptation to distinct dietary niches; results support earlier conclusions of a single panmictic population. The RAD sequence data revealed 40 new SNPs not previously detected in the species, and our sequence data can be used in future studies of ecotypic diversity in salmonid species.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allescher, H.D.; Ahmad, S.; Classen, M.

Receptor binding of the opioid receptor antagonist, ({sup 3}H)diprenorphine, which has a similar affinity to the various opioid receptor subtypes, was characterized in subcellular fractions derived from either longitudinal or circular smooth muscle of the canine small intestine with their plexuses (myenteric plexus and deep muscular plexus, respectively) attached. The distribution of opioid binding activity showed a good correlation in the different fractions with the binding of the neuronal marker ({sup 3}H)saxitoxin but no correlation to the smooth muscle plasma membrane marker 5'-nucleotidase. The saturation data (Kd = 0.12 +/- 0.04 nM and maximum binding = 400 +/- 20 fmol/mg)more » and the data from kinetic experiments (Kd = 0.08 nmol) in the myenteric plexus were in good agreement with results obtained previously from the circular muscle/deep muscular plexus preparation. Competition experiments using selective drugs for mu (morphiceptin-analog (N-MePhe3-D-Pro4)-morphiceptin), delta (D-Pen2,5-enkephalin) and kappa (dynorphin 1-13, U50488-H) ligands showed the existence of all three receptor subtypes. The existence of kappa receptors was confirmed in saturation experiments using ({sup 3}H) ethylketocycloazocine as labeled ligand. Two putative opioid agonists, with effects on gastrointestinal motility, trimebutine and JO-1196 (fedotozin), were also examined. Trimebutine (Ki = 0.18 microM), Des-Met-trimebutine (Ki = 0.72 microM) and Jo-1196 (Ki = 0.19 microM) displaced specific opiate binding. The relative affinity for the opioid receptor subtypes was mu = 0.44, delta = 0.30 and kappa = 0.26 for trimebutine and mu = 0.25, delta = 0.22 and kappa = 0.52 for Jo-1196.« less

Mid-infrared emissions of Pr{sup 3+}-doped GeS{sub 2}–Ga{sub 2}S{sub 3}–CdI{sub 2} chalcohalide glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Chunfeng; Guo, Haitao, E-mail: guoht_001@opt.ac.cn; Xu, Yantao

2014-12-15

Graphical abstract: ∼4.6 μm mid-infrared fluorescence emission from Pr{sup 3+} in the sulfide glass is successfully observed at room temperature excited by a 2.01 μm Tm{sup 3+}:YAG ceramic laser system. - Highlights: • Serial Pr{sup 3+}-doped GeS{sub 2}–Ga{sub 2}S{sub 3}–CdI{sub 2} chalcohalide glasses were synthesized. • ∼4.6 μm mid-infrared fluorescence from Pr{sup 3+} was observed at room temperature. • The compositional dependence of luminescence properties was studied. • Radiative properties have been determined using the Judd–Ofelt theory. - Abstract: For elucidation of the glass composition’s influence on the spectroscopic properties in the chalcohalide system and the discovery of a newmore » material for applications in mid-infrared fiber-lasers, a serial Pr{sup 3+}-doped (100 − x)(0.8GeS{sub 2}·0.2Ga{sub 2}S{sub 3})xCdI{sub 2} (x = 5, 10, 15 and 20) chalcohalide glasses were prepared. ∼4.6 μm mid-infrared fluorescence emission from Pr{sup 3+} in the sulfide glass is successfully observed at room temperature excited by a 2.01 μm Tm{sup 3+}:YAG ceramic laser system, and the effective line-width of fluorescence band is 106–227 nm. Intense compositional dependence of mid-infrared emissions is found. The radiative rates of Pr{sup 3+} ions in these glasses were calculated by using the Judd–Ofelt theory.« less

77 FR 67368 - Medicare and Medicaid Programs; Quarterly Listing of Program Issuances-July through September 2012

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-09

...) Facilities. XIII Medicare-Approved Lung JoAnna Baldwin, MS. (410) 786-7205 Volume Reduction Surgery Facilities. XIV Medicare-Approved Bariatric Kate Tillman, RN, (410) 786-9252 Surgery Facilities. MAS. XV...

Cluster Core Curriculums for E.E.E.

ERIC Educational Resources Information Center

Pratt, Arden L.

1970-01-01

The development of an interdisciplinary course in environmental and ecological education, and the construction of guidelines for a core experience in environmental occupational education were the major objectives of more than 60 educators attending the Ecological Technician Education Workshop. (JO)

Older adults abuse in three Brazilian cities.

PubMed

Rodrigues, Rosalina Aparecida Partezani; Monteiro, Edilene Araújo; Santos, Ana Maria Ribeiro Dos; Pontes, Maria de Lourdes de Farias; Fhon, Jack Roberto Silva; Bolina, Alisson Fernandes; Seredynskyj, Fernanda Laporti; Almeida, Vanessa Costa; Giacomini, Suelen Borelli Lima; Defina, Giovanna Partezani Cardoso; Silva, Luipa Michele

2017-01-01

To analyze the police reports filed by older adults who suffered abuse in order to identify the socio-demographic characteristics of victims and aggressors, type of violence, location, as well as to compare rates in three Brazilian cities in the period from 2009 to 2013. Ecological study, in which 2,612 police reports registered in Police Stations were analyzed. An instrument was used to obtain data from the victim, the aggressor and the type of violence. Psychological abuse predominated and most cases occurred in the older adults own home. In the cities of Ribeirão Preto and João Pessoa, the older adults presented similar rates for both gender. Regarding the standardized rates, in João Pessoa, there was a rise of this type of abuse in the two first years, and later there was a certain stability. In the city of Teresina, there was an increase, also observed in the city of Ribeirão Preto in the three first years, followed by a decrease. Older adults abuse is a cultural phenomenon difficult to be reported by them, since it occurs in the family context. Analisar os boletins de ocorrência registrados por idosos que sofreram violência, a fim de identificar características sociodemográficas das vítimas e dos agressores, tipo de violência, local, bem como comparar as taxas em três municípios brasileiros no período de 2009 a 2013. Estudo ecológico, em que foram analisados 2.612 boletins de ocorrência registrados em Delegacias do Idoso. Utilizou-se um instrumento para obter dados da vítima, do agressor e tipo de violência. Predominou a violência psicológica, na maioria dos casos na própria residência do idoso. Em Ribeirão Preto e João Pessoa, os idosos mais jovens apresentaram taxas semelhantes entre ambos os sexos. Na comparação das taxas padronizadas, em João Pessoa, houve ascensão deste tipo de violência nos dois primeiros anos, e, posteriormente, certa estabilidade. Em Teresina, houve ascensão, também observada em Ribeirão Preto nos três primeiros anos, seguida de decréscimo. A violência é um fenômeno cultural de difícil notificação pelo idoso, por ocorrer no contexto familiar.

Rift-plume interaction reveals multiple generations of recycled oceanic crust in Azores lavas

NASA Astrophysics Data System (ADS)

Béguelin, Paul; Bizimis, Michael; Beier, Christoph; Turner, Simon

2017-12-01

We present 176Hf/177Hf isotope ratios on 41 previously well-characterized subaerial and submarine samples from the Azores islands of São Miguel, Terceira, Graciosa, Faial, Pico and the João de Castro seamount (on the Terceira Rift). In εNd-εHf isotope space all Azores lavas fall below the mantle array reference line and do not overlap the proximal Atlantic MORB. Lavas from São Miguel and João de Castro form two distinct and well defined arrays extending below the mantle array, which has not been previously documented in other oceanic magmatic provinces. The Nd-Hf isotope compositions of João de Castro overlap those of HIMU type lavas, yet they lack the characteristically radiogenic Pb isotope ratios of HIMU. The combined Nd-Hf-Pb-Sr isotope systematics of both São Miguel and João de Castro endmembers can be explained by recycling of a single package of heterogeneous oceanic crust ranging from D-MORB to E-MORB in composition, with an age between 2.5 and 3.0 Ga, with no requirement for parent-daughter ratio modification during subduction. In contrast the Nd-Hf-Pb isotope systematics of lavas from São Jorge, Terceira, Graciosa, Pico and Faial are consistent with the presence of younger (<700 Ma) recycled crust that underwent low-temperature alteration and dehydration during subduction. There is no evidence in the erupted lavas for direct mixing between these two generations of recycled material within the plume. These data suggest that old recycling age and absence of sediments along with recycled oceanic crust are both required to develop isotopic compositions below the mantle array in εNd-εHf space. Our modeling shows that the compositional variability of erupted MORB is large enough that, given enough time, they can generate a wide range of isotope compositions such as observed in OIB. Lastly, lava compositions along the Terceira rift can be explained by a westward asthenospheric flux along a tilted lithosphere/asthenosphere boundary, where fertile components are exhausted by partial melting after ∼70 km of transport along the Terceira Rift. While this observation is broadly consistent with the plume source-ridge sink model, it also suggests that the lithosphere/asthenosphere boundary geometry can smear the view of the plume heterogeneity.

Ceteacean Social Behavioral Response to Sonar

DTIC Science & Technology

2013-09-30

review). The social context of individual foraging behaviour in long-finned pilot whales (Globicephala melas ). Aoki K, Sakai M, Miller JO, Visser F...during 8 experimental exposures of killer (Orcinus orca), long-finned pilot whale (Globicephala melas ), and sperm whale (Physeter macrocephalus

Catalyst Exchange.

ERIC Educational Resources Information Center

Floyd, Debbie L., Ed.

1981-01-01

Contains John Hoffman's "Continuing Education for the Elderly," which describes Panola Junior College's (Texas) programs; Judith Seed's "Tutor Training for Business and Industry," on La Guardia Community College's (New York) Adult Learning Center; and "Secretaries as Professionals" by Jo Lynn Samuelson, describing Sierra College's (California)…

Organizational Paradigm Shifts.

ERIC Educational Resources Information Center

National Association of College and University Business Officers, Washington, DC.

This collection of essays explores a new paradigm of higher education. The first essay, "Beyond Re-engineering: Changing the Organizational Paradigm" (L. Edwin Coate), suggests a model of quality process management and a structure for managing organizational change. "Thinking About Consortia" (Mary Jo Maydew) discusses…

After chemotherapy - discharge

MedlinePlus

... References Doroshow JH. Approach to the patient with cancer. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 179. Freifeld AG, Kaul DR. Infection in the patient with cancer. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan ...

Jointless bridges : final report.

DOT National Transportation Integrated Search

1981-01-01

The results of this study are reported in two parts. The first deals with the various methods states are employing to reduce the number of joints in bridge decks. The most common method is the use of integral abutments, where the superstructure is jo...

Inflammatory Myopathies (Myositis)

MedlinePlus

... that can people with a virus called HTLV-1. Some myositis cases have followed infec- tion with the Coxsackie B ... only mildly elevated, or even normal. In some cases, the doctor may ask for ... muscle disease. One such antibody is called Jo-1 . The next ...

Computer-Aided Design and Analysis of Digital Guidance and Control Systems.

DTIC Science & Technology

1983-07-01

w. O M0 4 z Q.C u0 LC 0 -C LC0 L Ww N a’ 00 - U C to _..q Q 0 c C0 * - C)Q 0 0 (’ UOA- r40 0 U - -r -0 >L00C 0 & c 40 kA 0 - ;( b C .- 0 UOC. CL 0...8217Oka O0 . cc0>- lc0 0O 6, EC ! zz Oor- L-IC 0 0 - CUa-! 0 aJO C. 0 0. aa ~ .a " -IQ - , 0 ak Uu Ou 0 -- U C 0- E-0 L’ 0!- C0-0- a SC -- 00.4.6a. C

The relationship between neuropsychological tests of visuospatial function and lobar cortical thickness.

PubMed

Zink, Davor N; Miller, Justin B; Caldwell, Jessica Z K; Bird, Christopher; Banks, Sarah J

2018-06-01

Tests of visuospatial function are often administered in comprehensive neuropsychological evaluations. These tests are generally considered assays of parietal lobe function; however, the neural correlates of these tests, using modern imaging techniques, are not well understood. In the current study we investigated the relationship between three commonly used tests of visuospatial function and lobar cortical thickness in each hemisphere. Data from 374 patients who underwent a neuropsychological evaluation and MRI scans in an outpatient dementia clinic were included in the analysis. We examined the relationships between cortical thickness, as assessed with Freesurfer, and performance on three tests: Judgment of Line Orientation (JoLO), Block Design (BD) from the Fourth edition of the Wechsler Adult Intelligence Scale, and Brief Visuospatial Memory Test-Revised Copy Trial (BVMT-R-C) in patients who showed overall average performance on these tasks. Using a series of multiple regression models, we assessed which lobe's overall cortical thickness best predicted test performance. Among the individual lobes, JoLO performance was best predicted by cortical thickness in the right temporal lobe. BD performance was best predicted by cortical thickness in the right parietal lobe, and BVMT-R-C performance was best predicted by cortical thickness in the left parietal lobe. Performance on constructional tests of visuospatial function appears to correspond best with underlying cortical thickness of the parietal lobes, while performance on visuospatial judgment tests appears to correspond best to temporal lobe thickness. Future research using voxel-wise and connectivity techniques and including more diverse samples will help further understanding of the regions and networks involved in visuospatial tests.

Phosphorescence In Bacillus Spores

DTIC Science & Technology

2003-07-01

commonly causing acute otitis media (middle ear infections) is present in an animal model. We will briefly review this application since it shows that...causing acute otitis media in a chinchilla model. Laryngoscope.110, 1119-1123, (2000). 2. C.D. Bluestone, J.O. Klein, Otitis media , atelesctasis

Ray Next-Event Estimator Transport of Primary and Secondary Gamma Rays

DTIC Science & Technology

2011-03-01

McGraw-Hill. Choppin, G. R., Liljenzin, J.-O., & Rydberg, J. (2002). Radiochemistry and Nuclear Chemistry (3rd ed.). Woburn, MA: Butterworth- Heinemann ...time-energy bins. Any performance enhancements (maybe parallel searching?) to the search routines decrease estimator computational time

75 FR 67749 - Notice of Agreements Filed

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-03

... Association. Parties: Ports Baltimore, Inc.; Maryland International Terminals, Inc.; Mid-Atlantic Terminal LLC; Ceres Marine terminals, Inc.; Tartan Terminals, Inc. and Ports America Chesapeake, Inc. Filing Party: Jo.... Synopsis: The amendment increases the amount of space CMA CGM is allotted from Pacific Northwest ports...

U.S. EPA, Pesticide Product Label, CHACON ORNAMENTAL SPRAY, 03/24/1981

EPA Pesticide Factsheets

2011-04-14

,-. ., I I ~ '- . ; i I l 0 " j ,. '" 1 ~}.:. I \\ I " Ii jO ; i)c , <,! , i .:::: I '-OJ ! ., ,~ 0 -...!D-"- - • II r " ,? .' I I , I .(. i- I 0 , <1, {2 0 \\ " I ~ ! p t " ~ I " a " I) " \\ " " ...

I hope the memory café initiative takes off in hospitals across the UK.

PubMed

Ryan, Bridget

2014-12-15

What a wonderful 'Tea and sympathy' piece from staff nurse Katy Hope and assistant practitioner Jo Pope (Reflections December 3) about the 'memory café' for patients with dementia at the West Cornwall Hospital in Penzance.

Writing Instruction.

ERIC Educational Resources Information Center

Richgels, Donald J.

2003-01-01

Discusses four recent writing books: "Teaching to Write: Theory Into Practice" (Jane B. Hughey and Charlotte Slack); "The Writing Teacher's Handbook" (Jo Phenix); "Scaffolding Young Writers: A Writers' Workshop Approach" (Linda J. Dorn and Carla Soffos); and "Directing the Writing Workshop: An Elementary Teacher's Handbook" (Jean Wallace Gillet…

Precision cylinder optics for higher requirements; Techical Digest

NASA Astrophysics Data System (ADS)

Bergner, Dieter; Falkenstorfer, Oliver; Malina, Dirk; Roder, Janett; Schreiner, Roland

2005-05-01

JENOPTIK Laser, Optik, Systeme GmbH (JO L.O.S.) enlarged its product range in the field of cylinder lenses and crystal optics. These components are used in optical measuring technology and in various laser applications. The new cylinder components are a result of the state of the art manufacturing technology. For applications, where the quality of standard cylinders with a surface deviation of PV Lambda/2 to Lambda/5 @632,8nm and tested with a reference glass only is not sufficient, the surface shape can be improved to PV Lambda/10 @632,8nm. The presentation deals with Jenoptik's current state to produce cylinder optics, to reduce remaining surface shape deviations of semi-finished cylinder optics and to test these elements. Based on in-house developed machinery, cylinders are manufactured by means of blocking or drum. The required surface quality in the range of PV Lambda/10 @632,8nm for cylindrical lenses can be reached by computer aided correction using mrf-polishing techniques in connection with an interferometer test set-up. Therefore, the polishing machine is equipped with an additional axis of movement. The interferometer measurement of the residual surface deviation is done by Computer Generated Holograms (CGH), which are designed and manufactured in-house. CGHs from JO L.O.S. for testing cylindrical lenses can be custom designed starting with F#1.0. They are related to the typical rectangular geometry of cylinder components. Using these measurement techniques, testing is no longer the limiting factor in achieving high quality cylindrical surfaces. JO L.O.S. has all the capabilities of effective manufacturing, testing and correcting cylindrical lenses. Latest results achieved in series production are shown.

Precision cylinder optics for higher requirements; Techical Digest

NASA Astrophysics Data System (ADS)

Bergner, Dieter; Falkenstorfer, Oliver; Malina, Dirk; Roder, Janett; Schreiner, Roland

2005-05-01

JENOPTIK Laser, Optik, Systeme GmbH (JO L.O.S.) enlarged its product range in the field of cylinder lenses and crystal optics. These components are used in optical measuring technology and in various laser applications. The new cylinder components are a result of the state of the art manufacturing technology. For applications, where the quality of standard cylinders with a surface deviation of PV~Lambda/2 to ~Lambda/5 @632,8nm and tested with a reference glass only is not sufficient, the surface shape can be improved to PV Lambda/10 @632,8nm. The presentation deals with Jenoptik's current state to produce cylinder optics, to reduce remaining surface shape deviations of semi-finished cylinder optics and to test these elements. Based on in-house developed machinery, cylinders are manufactured by means of blocking or drum. The required surface quality in the range of PV~Lambda/10 @632,8nm for cylindrical lenses can be reached by computer aided correction using mrf-polishing techniques in connection with an interferometer test set-up. Therefore, the polishing machine is equipped with an additional axis of movement. The interferometer measurement of the residual surface deviation is done by Computer Generated Holograms (CGH), which are designed and manufactured in-house. CGHs from JO L.O.S. for testing cylindrical lenses can be custom designed starting with F#1.0. They are related to the typical rectangular geometry of cylinder components. Using these measurement techniques, testing is no longer the limiting factor in achieving high quality cylindrical surfaces. JO L.O.S. has all the capabilities of effective manufacturing, testing and correcting cylindrical lenses. Latest results achieved in series production are shown.

V-Shaped Molecular Configuration of Wax Esters of Jojoba Oil in a Langmuir Film Model.

PubMed

Caruso, Benjamín; Martini, M Florencia; Pickholz, Mónica; Perillo, María A

2018-06-19

The aim of the present work was to understand the interfacial properties of a complex mixture of wax esters (WEs) obtained from Jojoba oil (JO). Previously, on the basis of molecular area measurements, a hairpin structure was proposed as the hypothetical configuration of WEs, allowing their organization as compressible monolayers at the air-water interface. In the present work, we contributed with further experimental evidence by combining surface pressure (π), surface potential (Δ V), and PM-IRRAS measurements of JO monolayers and molecular dynamic simulations (MD) on a modified JO model. WEs were self-assembled in Langmuir films. Compression isotherms exhibited π lift-off at 100 Å 2 /molecule mean molecular area ( A lift-off ) and a collapse point at π c ≈ 2.2 mN/m and A c ≈ 77 Å 2 /molecule. The Δ V profile reflected two dipolar reorganizations, with one of them at A > A lift-off due to the release of loosely bound water molecules and another one at A c < A < A lift-off possibly due to reorientations of a more tightly bound water population. This was consistent with the maximal SP value that was calculated according to a model that considered two populations of oriented water and was very close to the experimental value. The orientation of the ester group that was assumed in that calculation was coherent with the PM-IRRAS behavior of the carbonyl group with the C═O oriented toward the water and the C-O oriented parallel to the surface and was in accordance with their orientational angles (∼45 and ∼90°, respectively) determined by MD simulations. Taken together, the present results confirm a V shape rather than a hairpin configuration of WEs at the air-water interface.

Physical and biochemical energy balance during an isometric tetanus and steady state recovery in frog sartorius at 0 degree C

PubMed Central

1983-01-01

Frog sartorius muscle stimulated isometrically for 3 s every 256 s to attain a steady state in which initial heat (QI), recovery heat (QR), rate of O2 consumption (JO2), and isometric force (PO) generated are constant for each cycle. For a 3-s tetanus given every 256 s, JO2 was 0.106 mumol/(min . g blotted weight), approximately 71% of the maximum rate observed, whereas lactate production was negligible under these conditions. QI, QT(= QI + QR), and QT/QI were 88.2, 181.5, 2.06 mJ/g blotted weight, respectively. The high-energy phosphate breakdown (delta approximately P) breakdown during the first 3-s tetanus was not different from that during a contraction in the steady state and averaged 1.1 mumol/g blotted weight. Less than half of the initial heat could be accounted for in terms of the extent of the known chemical reactions occurring during contraction. From the stoichiometry of the theoretical biochemical pathways, the amount of ATP synthesized in the steady state exceeds delta approximately P during contraction by more than twofold, corresponding to an apparent ADP:O ratio of 1.5. If it is assumed that carbohydrate oxidation is the only net chemical reaction in the steady state, the total heat production can be explained on the basis of the measured JO2. Under this assumption, heat production during recovery was less than that expected on the basis of the oxygen consumption and delta approximately P during contraction. These observations support the hypothesis that the unexplained enthalpy production and low apparent ADP:O ratio are causally related, i.e., that the reaction(s) producing the unexplained heat during contraction is reversed during the recovery period. PMID:6601686

Implementation of public policy on alcohol and other drugs in Brazilian municipalities: comparative studies.

PubMed

Mota, Daniela Belchior; Ronzani, Telmo Mota

2016-07-01

One of the challenges with respect to public health and the abuse of alcohol and other drugs is to implement policies in support of greater co-ordination among various levels of government. In Brazil, policies are formulated by the Secretaria Nacional de Políticas sobre Drogas (SENAD - State Department for Policies on Drugs) and the Ministério da Saúde (MS - Ministry of Health). This study aims to compare implementation of policies adopted by SENAD and MS at the municipal level. Three municipalities were intentionally selected: Juiz de Fora having a larger network of treatment services for alcohol and drug users; Lima Duarte, a small municipality, which promotes the political participation of local actors (COMAD - Municipal Council on Alcohol and Drugs); and São João Nepomuceno, also a small municipality, chosen because it has neither public services specialised to assist alcohol and other drugs users, nor COMAD. Data collection was conducted through interviews with key informants (n = 19) and a review of key documents concerned with municipal policies. Data analysis was performed using content analysis. In Juiz de Fora, there are obstacles regarding the integration of the service network for alcohol and other drug users and also the articulation of local actors, who are predominant in the mental health sector. In Lima Duarte, while there is a link between local actors through COMAD, their actions within the local service network have not been effective. In São João Nepomuceno, there were no public actions in the area of alcohol and drugs, and consequently insufficient local debate. However, some voluntary, non-governmental work has been undertaken. There were weaknesses in the implementation of national-level policies by SENAD and the MS, due to the limited supply of available treatment, assistance and the lack of integration among local actors. © 2015 John Wiley & Sons Ltd.

Physical and chemical characterization of residual oil-fired power plant emissions

EPA Science Inventory

Although the toxicity of oil combustion emissions is a significant public health concern, few studies characterize the emissions from plant-scale utility boilers firing residual oil. This study remedies that deficiency by sampling and monitoring stack emissions from a 432 Giga Jo...

Partnerships Across Organizations. [SITE 2002 Section].

ERIC Educational Resources Information Center

2002

This document contains the following papers on partnerships across organizations from the SITE (Society for Information Technology & Teacher Education) 2002 conference: (1) "Modeling Instruction with Modern Information and Communications Technology: The MIMIC Project" (Ronale J. Abate; Jim Meinke; Mary Jo Cherry; Pam Cook; Jennifer Merritt); (2)…

76 FR 48563 - Medicare and Medicaid Programs; Quarterly Listing of Program Issuances-January Through March 2011...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-08

...-7205 Ventricular Assist Device (Destination Therapy) Facilities. XIII Medicare-Approved Lung JoAnna...-Approved Ventricular Assist Device (Destination Therapy) Facilities, Addendum XIII: Lung Volume Reduction...-Approved Ventricular Assist Device (Destination Therapy) Facilities (January Through March 2011) Addendum...

2. Historic American Buildings Survey Joseph Hill, Photographer October 28, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Historic American Buildings Survey Joseph Hill, Photographer October 28, 1936 #1 DOORWAY MAXIENER HOUSE 104 South Bench Street, Galena, Ill. (Said to be oldest frame house in Galena) - Galena Doorways, Elizabeth Maxiener Cottage, 104 South Bench Street, Galena, Jo Daviess County, IL

Management and Technology Division. Papers.

ERIC Educational Resources Information Center

International Federation of Library Associations, The Hague (Netherlands).

Two papers on copyright and privacy considerations of international information transfer were presented at the 1982 International Federation of Library Associations (IFLA) conference. In "Findings of the IFLA International Study on the Copyright of Bibliographic Records in Machine-Readable Form," Dennis D. McDonald, Eleanor Jo Rodger,…

Electrical Interactions between Mammalian Cortical Neutons

DTIC Science & Technology

1990-05-24

direct responses to acetyl- the entire mammalian central nervous sys- choline and nicotine. Deadvyler and col- teni (19, 32).’The development of...BERT J. (1985) Neurotoxic lesion ; of the athmic neurons recorded near the par-anterior hypothalamus disrupt the JoSentricular in vitro. Brain Res. Bull

Before Big Science: The Pursuit of Modern Chemistry and Physics 1800-1940

NASA Astrophysics Data System (ADS)

Todd, David

1997-07-01

Mary Jo Nye. Twayne, An Imprint of Simon & Schuster Macmillan: New York, 1996. 282 pp, 11 illus. ISBN 0-8057-9512-X. Cloth. $32.95. Mary Jo Nye, Professor of Humanities and History at Oregon State University, has, since at least 1972, been publishing in the area of the history of science - in particular, physics and chemistry. Her latest book goes at length into the difficulties encountered by 19th century chemists in working out relative atomic weights and the geometry of bound carbon, and by physicists in coping with the problems of the nature of light, whether heat was a fluid or not, and the mechanical equivalent of heat, and problems posed by magnetism and electricity. An example of the mental blocks that had to be overcome is the author's quotation of a French chemist's statement to his students in the late 19th century that "bodies which are not volatile do not have molecular weight", since their molecular weights could not be determined by the Dumas method.

Prime Contract Awards Alphabetically by Contractor, by State or Country, and Place. Part 3 (Ashley Steel Inc-Bettencourt R E Inc)

DTIC Science & Technology

1990-01-01

Jin -JIn -j In -j In -1 O -. 100 -. 1000 I,. Hf - M (-4 Hic -.1JC ~In -JO0 . JCI -J in -.i n .1(1 -i in -JO0 . .04 .J044C C)~ 11(0M-4 ’wCD w LC W0...co 10.oc *< < 04-. <g < 4 4c 4( < � in- inIB- N N NNNNNNN con 004Co 100 * I0-4C)0B00 0 000 00 0-0 00 C00000C000 0 *I-4 Cl0 0c 0 000 0 0. 0...oI 011 0JN 0 r- r- -. 0cI 00 0.4 0 " NNN C S S N CYINSC4 04 NS C4 - M 0-4"ə L- a WjIn .. (D(0(0 CC4 >.N XN ( -000000 0 -N 1 100 -4N4 lUli < tg N -4C

KENNEDY SPACE CENTER, FLA. - KSC External Relations and Business Development Director JoAnn Morgan (sixth from right) joins other attendees of The Florida Commission on the Status of Women held June 7 at the Debus Conference Facility. Morgan is a member of the group’s Hall of Fame. The commission, through coordinating, researching, communicating, and encouraging legislation, is dedicated to empowering women from all walks of life in achieving their fullest potential, to eliminating barriers to that achievement, and to recognizing women’s accomplishments.

NASA Image and Video Library

2003-06-07

KENNEDY SPACE CENTER, FLA. - KSC External Relations and Business Development Director JoAnn Morgan (sixth from right) joins other attendees of The Florida Commission on the Status of Women held June 7 at the Debus Conference Facility. Morgan is a member of the group’s Hall of Fame. The commission, through coordinating, researching, communicating, and encouraging legislation, is dedicated to empowering women from all walks of life in achieving their fullest potential, to eliminating barriers to that achievement, and to recognizing women’s accomplishments.

Ram Pressure Stripping of Galaxy JO201

NASA Astrophysics Data System (ADS)

Zhong, Greta; Tonnesen, Stephanie; Jaffé, Yara; Bellhouse, Callum; Bianca Poggianti

2017-01-01

Despite the discovery of the morphology-density relation more than 30 years ago, the process driving the evolution of spiral galaxies into S0s in clusters is still widely debated. Ram pressure stripping--the removal of a galaxy's interstellar medium by the pressure of the intracluster medium through which it orbits--may help explain galactic evolution and quenching in clusters. MUSE (Multi Unit Spectroscopic Explorer) observational data of galaxy JO201 in cluster Abell 85 reveal it to be a jellyfish galaxy--one with an H-alpha emitting gas tail on only one side. We model the possible orbits for this galaxy, constrained by the cluster mass profile, line of sight velocity, and projected distance from the cluster center. Using Enzo, an adaptive mesh refinement hydrodynamics code, we simulate effects of ram pressure on this galaxy for a range of possible orbits. We present comparisons of both the morphology and velocity structure of our simulated galaxy to the observations of H-alpha emission.

Novel materials as potential infrared laser hosts

NASA Astrophysics Data System (ADS)

Sarkies, Julian Richard

The work presented in this thesis has concentrated on an assessment and characterisation of potential laser host media which will only support low phonon or vibrational modes. This is a necessary criterion if systems in which the active ions are lanthanides are to be made to lase in the mid-infrared, as in conventional host media non- radiative processes dominate transitions in this region. Research has concentrated upon two main areas. Firstly a spectroscopic study of lanthanide doped PBr3/AlBr3/SbBr3 was undertaken. A detailed investigation and characterisation of the stable solution formation region was carried out. The doping levels achievable were seen to vary across the lanthanide series from a maximum 0.24mol% for praesodymium to a minimum 0.15mol% for ytterbium. Energies of the characteristic 4 f absorptions of the trivalent lanthanides were measured, along with their oscillator strengths. Judd-Ofelt parameters were found for several rare earths. Stimulated emission cross sections were found to be higher than in conventional glass hosts for certain transitions, such as 6.83 × 10 -20 cm2 for the 4F3/2 --> 4I11/2 transition in the Nd3+ doped liquid. This was verified both experimentally and by the Ladenburg-Fuchtbauer relation when compared to a standard silicate glass. The behaviour, both spectroscopic and physical, of the doped solutions was seen to change dramatically upon heating. Heating the solutions gave rise to higher crystallisation rates, but lower non-radiative relaxation rates. Waveguide and laser experiments were attempted in both bulk and capillary geometries, however material factors such as crystallisation and thermal lensing prevented laser action. Secondly, rare earth doped planar waveguides of zinc sulphide were prepared. A full characterisation of the way in which waveguide loss was affected by factors such as deposition rate, doping level and waveguide masking during evaporation was performed. Waveguide losses as low as 1.5dB/cm at 980nm were measured. The loss was seen to have a strong λ-4 dependence, indicating it was predominantly due to Rayleigh scattering. Deposition onto heated substrates and post deposition annealing increased the loss significantly. Shielding the substrate from the radiant heating of the evaporation boat by partial masking of the substrate reduced the loss significantly. Doping the films caused a large increase in the loss for dopant concentrations of above 0.8mol%. Emission was observed from both Er3+ and Nd 3+ doped waveguides, and fluorescent lifetimes measured. The emission cross sections were measured for the 4F3/2 --> 4I11/2 transition in the Nd3+ doped waveguide, and for the 4I13/2 --> 4I 15/2 transition in the Er3+ doped waveguide. Multilayer dielectric mirrors were deposited onto the ends of a Nd3+ doped waveguide, forming a fully integrated resonator. The low damage threshold of the multilayer coatings precluded laser action. These results are believed to be the first ever reported for thermally evaporated doped zinc sulphide waveguides. This system has shown considerable promise as an infrared laser host, the future implications of this work are discussed and possible directions for future research suggested.

Calibration and evaluation of CCD spectroradiometers for ground-based and airborne measurements of spectral actinic flux densities

NASA Astrophysics Data System (ADS)

Bohn, Birger; Lohse, Insa

2017-09-01

The properties and performance of charge-coupled device (CCD) array spectroradiometers for the measurement of atmospheric spectral actinic flux densities (280-650 nm) and photolysis frequencies were investigated. These instruments are widely used in atmospheric research and are suitable for aircraft applications because of high time resolutions and high sensitivities in the UV range. The laboratory characterization included instrument-specific properties like the wavelength accuracy, dark signal, dark noise and signal-to-noise ratio (SNR). Spectral sensitivities were derived from measurements with spectral irradiance standards. The calibration procedure is described in detail, and a straightforward method to minimize the influence of stray light on spectral sensitivities is introduced. From instrument dark noise, minimum detection limits ≈ 1 × 1010 cm-2 s-1 nm-1 were derived for spectral actinic flux densities at wavelengths around 300 nm (1 s integration time). As a prerequisite for the determination of stray light under field conditions, atmospheric cutoff wavelengths were defined using radiative transfer calculations as a function of the solar zenith angle (SZA) and total ozone column (TOC). The recommended analysis of field data relies on these cutoff wavelengths and is also described in detail taking data from a research flight on HALO (High Altitude and Long Range Research Aircraft) as an example. An evaluation of field data was performed by ground-based comparisons with a double-monochromator-based, highly sensitive reference spectroradiometer. Spectral actinic flux densities were compared as well as photolysis frequencies j(NO2) and j(O1D), representing UV-A and UV-B ranges, respectively. The spectra expectedly revealed increased daytime levels of stray-light-induced signals and noise below atmospheric cutoff wavelengths. The influence of instrument noise and stray-light-induced noise was found to be insignificant for j(NO2) and rather limited for j(O1D), resulting in estimated detection limits of 5 × 10-7 and 1 × 10-7 s-1, respectively, derived from nighttime measurements on the ground (0.3 s integration time, 10 s averages). For j(O1D) the detection limit could be further reduced by setting spectral actinic flux densities to zero below atmospheric cutoff wavelengths. The accuracies of photolysis frequencies were determined from linear regressions with data from the double-monochromator reference instrument. The agreement was typically within ±5 %. Because optical-receiver aspects are not specific for the CCD spectroradiometers, they were widely excluded in this work and will be treated in a separate paper, in particular with regard to airborne applications.

An experimental comparison of two adaptation strategies in an adaptive-walls wind-tunnel

NASA Astrophysics Data System (ADS)

Russo, G. P.; Zuppardi, G.; Basciani, M.

1995-08-01

In the present work an experimental comparison is made between two adaptation strategies: the Judd's method and the Everhart's method. A NACA 0012 airfoil has been tested at Mach numbers up to 0.4: models with chords up to 200 mm have been tested in a 200 mm × 200 mm test section. The two strategies, though based on different theoretical approaches, show a fairly good agreement as far as c p distribution on the model, lift and drag curves and residual interference are concerned and agree, in terms of lift curve slope and drag coefficient at zero lift, with the McCroskey correlation.

FLES News, Volume 3, Numbers 1-3, 1989-1990.

ERIC Educational Resources Information Center

FLES News, 1990

1990-01-01

These three issues of the FLES News newsletter contain the following articles: "What I Learned in Second Grade: A French Teacher's Experience" (Pat Westphal); "Foreign Language Program Articulation: Building Bridges from Elementary to Secondary School" (Jo Anne Wilson; an ERIC Digest); "How Do Principals View Foreign…

Handbook of Perceptual Dialectology, Volume 1.

ERIC Educational Resources Information Center

Preston, Dennis R., Ed.

This collection of 22 papers offers a detailed record of the development of the field and its modern extension. Part 1, "The Dutch Contribution: 'Little Arrows'," includes: (1) "Informant Classification of Dialects" (W.G. Rensink); (2) "Dialects" (Jo C. Daan); and (3) "The Netherlands-German National Border as a…

50 CFR Appendix A to Chapter I - Codes for the Representation of Names of Countries (Established by the International Organization...

Code of Federal Regulations, 2011 CFR

2011-10-01

... Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) Ch.... Israel IL. Italy IT. Ivory Coast CI. Jamaica JM. Japan JP. Jordan JO. Kenya KE. Kiribati KI. Kuwait KW...

50 CFR Appendix A to Chapter I - Codes for the Representation of Names of Countries (Established by the International Organization...

Code of Federal Regulations, 2010 CFR

2010-10-01

... Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) Ch.... Israel IL. Italy IT. Ivory Coast CI. Jamaica JM. Japan JP. Jordan JO. Kenya KE. Kiribati KI. Kuwait KW...

Bayesian analysis of CCDM models

NASA Astrophysics Data System (ADS)

Jesus, J. F.; Valentim, R.; Andrade-Oliveira, F.

2017-09-01

Creation of Cold Dark Matter (CCDM), in the context of Einstein Field Equations, produces a negative pressure term which can be used to explain the accelerated expansion of the Universe. In this work we tested six different spatially flat models for matter creation using statistical criteria, in light of SNe Ia data: Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC) and Bayesian Evidence (BE). These criteria allow to compare models considering goodness of fit and number of free parameters, penalizing excess of complexity. We find that JO model is slightly favoured over LJO/ΛCDM model, however, neither of these, nor Γ = 3αH0 model can be discarded from the current analysis. Three other scenarios are discarded either because poor fitting or because of the excess of free parameters. A method of increasing Bayesian evidence through reparameterization in order to reducing parameter degeneracy is also developed.

Why self-care is key to providing high-quality care to others.

PubMed

McCormick, Jo; Hayes, Sally

2017-06-22

Jo McCormick, Consultant Nurse and Associate Director of Nursing, Belfast Health and Social Care Trust, Joanna.McCormick@belfasttrust.hscni.net , and Sally Hayes, Director of Strategy, Planning and Resources at the Open University, share their insights from undertaking a Florence Nightingale Leadership Scholarship.

GLCF: Publications

Science.gov Websites

Services Contact Site Map Go Publications 2017 Che, X., Feng, M., Sexton, J. O., Channan, S., Yang, Y ., Choate, D., Stoner, D., Arundel, T., Hansen, J., Theimer, T., Holton, B., Jansen, B., Sexton, J.O. and successful acquisitions. Wildlife Society Bulletin. Brinck, K., Fischer, R., Groeneveld, J., Lehmann, S., De

Career Change: Implications for Vocational Education.

ERIC Educational Resources Information Center

De Sanctis, Vincent, Comp.

The four papers in this document consider alternative programs and innovative models and techniques concerned with career change and its impact on vocational education. In the first paper, Jo Shuchat addresses the issue of what vocational education is or is not doing to accommodate the increasing interest women have for nontraditional job…

76 FR 52287 - Political Activity-Federal Employees Residing In Designated Localities

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-22

... 21, 2011. ADDRESSES: Comments may be mailed to Elaine Kaplan, General Counsel, Room 7355, United... CONTACT: Jo-Ann Chabot, Office of the General Counsel, United States Office of Personnel Management, (202... Government of the District of Columbia. Section 7323(a) generally permits Federal employees who are not...

Prepare to be Wrong: Assessing and Designing for Adaptability, Flexibility, and Responsiveness

DTIC Science & Technology

2013-04-01

Deshmukh , Abhijit, Barry Boehm, Tom Housel, Dave Jacques, Supannika Koolmanojwong, Jo Ann Lane, Alan Levin, Brandon Pope, MAJ Erin Ryan, and Martin...October 2012. Deshmukh , Abhijit, Martin Wortman, Barry Boehm, Dave Jacques, Tom Housel, Kevin Sullivan, and Paul Collopy. “RT-18: Value of

Access to Justice: Secondary School Strategies.

ERIC Educational Resources Information Center

Khanlian, John F.; And Others

1989-01-01

John F. Khanlian, Ericka B. Gray and Sandi Dittrich offer a role playing activity on mediation. Jo Ellen Ambrose's and John Nelson's lessons deal with arbitration. Lowell Ueland's simulation is concerned with plea bargaining, and Jack Hanna's activity involves a discussion of lawyer responsibility to provide pro bono services. (KO)

A Review of The Sex EDcyclopedia

ERIC Educational Resources Information Center

Herman, Jeff; Andelloux, Megan

2012-01-01

While virtually all sex education books for teenagers focus on sexual health, Jo Langford's "The Sex EDcyclopedia" offers comprehensive and empowering information specifically for teen males about their sexuality and how it may be positively experienced. This review examines the strengths of "The Sex EDcyclopedia" as a sex education resource and…

Life Cycle Assessment as an Environmental Management Tool

EPA Science Inventory

Listed by Time Magazine as the method behind calculating “Ecological Intelligence,” one of “10 Ideas Changing the World Right Now” (March 23, 2009), Life Cycle Assessment (LCA) is the tool that is used to understand the environmental impacts of the products we make and sell. Jo...

40 CFR 81.314 - Illinois.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Rock Island County X Whiteside County X AQCR 70: Madison County: Wood River Twp X Alton Twp X All other... Johnson County X Pope County X Pulaski County X Union County X AQCR 73 Boone County X De Kalb County X... Jersey County Unclassifiable/Attainment Jo Daviess County Unclassifiable/Attainment Johnson County...

40 CFR 81.314 - Illinois.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Rock Island County X Whiteside County X AQCR 70: Madison County: Wood River Twp X Alton Twp X All other... Johnson County X Pope County X Pulaski County X Union County X AQCR 73 Boone County X De Kalb County X... Jersey County Unclassifiable/Attainment Jo Daviess County Unclassifiable/Attainment Johnson County...

"Ask Argonne" - Charlie Catlett, Computer Scientist, Part 2

ScienceCinema

Catlett, Charlie

2018-02-14

A few weeks back, computer scientist Charlie Catlett talked a bit about the work he does and invited questions from the public during Part 1 of his "Ask Argonne" video set (http://bit.ly/1joBtzk). In Part 2, he answers some of the questions that were submitted. Enjoy!

Two Tools Shaping NCDA's Place

ERIC Educational Resources Information Center

Feller, Rich, Ed.; Furbish, Dale, Ed.

2013-01-01

The authors are pleased to introduce the second pair of articles in the National Career Development Association (NCDA) Centennial Special Series celebrating the 100th anniversary of NCDA. In this issue, JoAnn Harris-Bowlsbey reviews the development and use of computer-assisted career guidance systems, and Juliette N. Lester, James Woods, and…

"Ask Argonne" - Charlie Catlett, Computer Scientist, Part 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Catlett, Charlie

2014-06-17

A few weeks back, computer scientist Charlie Catlett talked a bit about the work he does and invited questions from the public during Part 1 of his "Ask Argonne" video set (http://bit.ly/1joBtzk). In Part 2, he answers some of the questions that were submitted. Enjoy!

Forum: Knowledge, Action, Involvement

ERIC Educational Resources Information Center

Weinberger, JoAnn

2015-01-01

St. Clair (EJ1072357) provides a summary and lays out some of the important issues inherent in the broad strategies articulated in "Making Skills Everyone's Business: A Call to Transform Adult Learning in the United States" (MSEB) (United States Department of Education [USDoE], 2015) (see ED558793). In this commentary, JoAnn Weinberger…

Adventures in Assessment: Learner-Centered Approaches to Assessment and Evaluation in Adult Literacy, 2002.

ERIC Educational Resources Information Center

Cora, Marie, Ed.

2002-01-01

This journal presents the following articles: "Introduction: Volume 14--Examining Performance" (Marie Cora) "Fair Assessment Practices: Giving Students Equitable Opportunities to Demonstrate Learning" (Linda Suskie); "Assessing Oral Communication at the Community Learning Center Development of the OPT (Oral Proficiency Test)" (JoAnne Hartel and…

76 FR 16432 - National Institute of Neurological Disorders and Stroke; Notice of Closed Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-23

..., Neuroscience Center, 6001 Executive Boulevard, Rockville, MD 20852 (Virtual Meeting). Contact Person: JoAnn.../ NIH/DHHS/Neuroscience Center, 6001 Executive Boulevard, Suite 3208, MSC 9529, Bethesda, MD 20892-9529..., Clinical Research Related to Neurological Disorders; 93.854, Biological Basis Research in the Neurosciences...

Correction: An unsymmetrical non-fullerene acceptor: synthesis via direct heteroarylation, self-assembly, and utility as a low energy absorber in organic photovoltaic cells.

PubMed

Payne, Abby-Jo; Li, Shi; Dayneko, Sergey V; Risko, Chad; Welch, Gregory C

2017-09-21

Correction for 'An unsymmetrical non-fullerene acceptor: synthesis via direct heteroarylation, self-assembly, and utility as a low energy absorber in organic photovoltaic cells' by Abby-Jo Payne et al., Chem. Commun., 2017, 53, 10168-10171.

Supervisee Art-Based Disclosure in "El Duende" Process Painting

ERIC Educational Resources Information Center

Robb, Megan; Miller, Abbe

2017-01-01

Although art-based supervision often leads to supervisee disclosure, little is known about the experience, process, or contributions of such disclosure. We investigated the phenomenon of supervisee disclosure during "El Duende" Process Painting art-based group supervision using a qualitative study. JoHari's Window was used as a grounding…

An Active, Collaborative Approach to Learning Skills in Flow Cytometry

ERIC Educational Resources Information Center

Fuller, Kathryn; Linden, Matthew D.; Lee-Pullen, Tracey; Fragall, Clayton; Erber, Wendy N.; Röhrig, Kimberley J.

2016-01-01

Advances in science education research have the potential to improve the way students learn to perform scientific interpretations and understand science concepts. We developed active, collaborative activities to teach skills in manipulating flow cytometry data using FlowJo software. Undergraduate students were given compensated clinical flow…

Why We Fight: Mass Persuasion, Morale, and American Public Opinion from World War I Until the Present

DTIC Science & Technology

2014-06-01

fascist and Japanese imperial aggression, is generally considered straightforward. Can the same be said for propaganda’s effectiveness during the...multimedia propaganda include Film Propaganda in Britain and Nazi Germany: World War II Cinema , Jo Fox; Imagined Battles: Reflections on War in

Landmark-Based Navigation of an Unmanned Ground Vehicle (UGV)

DTIC Science & Technology

2009-03-01

against large measurement errors. 20090710280 RELEASE LIMITATION Approved for public release 4p fv^-Jo-osiit? Published by Weapons Systems Division...achieved as numerous low cost gyroscopes in the market meet this requirement. 24 DSTO-TR-2260 3.5.4 Sensitivity to Vehicle Speed In this subsection

A study of low threshold and high gain Nd3+ ions doped SiO2-B2O3-Na2CO3-NaF-CaF2 glasses for NIR laser applications

NASA Astrophysics Data System (ADS)

Megala, Rajesh; Gowthami, T.; John Sushma, N.; Kamala, S.; Deva Prasad Raju, B.

2018-05-01

Fluoroborosilicate glasses of composition 35SiO2-25B2O3-10Na2CO3-15NaF-15CaF2-xNd2O3 (where x = 0.1, 0.5. 1.0, 2.0 mol%) were prepared by melt quenching technique and various physical properties have been calculated. From the absorption spectra J-O Intensity parameters Ωλ (λ = 2, 4, 6) and radiative properties are evaluated by using J-O theory. The high values of Ω2 = 4.213 × 10-20 cm2, Ω4 = 5.345 × 10-20 cm2, Ω6 = 5.526 × 10-20 cm2 suggest that among the prepared glasses 0.5 mol% Nd glass is more asymmetric, more covalent and rigid in nature. The emission spectra were recorded with 808 nm laser as excitation source. The strong NIR emissions were observed at 876 nm, 1056 nm, 1328 nm corresponding to the transitions 4F3/2 → 4I9/2, 4F3/2 → 4I11/2, 4F3/2 → 4I13/2 respectively. Stimulated emission cross -section (σemi) and Gain bandwidth (σemi × Δλeff) were calculated. For 0.5 mol% Nd these values are found to be 3.30 × 10-20 cm2, 11 × 10-26 cm2. From the decay curve analysis the lifetime values for 4F3/2 level have been determined and these values are decreased with increase in Nd3+ ions concentration. These results may suggest that the prepared SBNCNd05 (Nd = 0.5 mol%) glass could be useful for 1056 nm laser applications.

More than Just Advice

ERIC Educational Resources Information Center

Olson, Cathy Applefeld

2013-01-01

Career counselor. Life coach. Holder of the occasional tissue box. It is all part of being a National Association for Music Education (NAfME) Collegiate advisor. Carla Jo Maltas, collegiate chapter advisor for the University of Central Missouri, would not have it any other way. Although the duties of an advisor vary depending on the institution…

Popular Education in Solidarity Economy

ERIC Educational Resources Information Center

de Melo Neto, José Francisco; da Costa, Francisco Xavier Pereira

2015-01-01

This article seeks to show the relation between popular education and solidarity economy in experiences of solidarity economy enterprises in Brazil. It is based on diverse experiences which have occurred in various sectors of this economy, highlighting those experiences which took place in João Pessoa with the creation of a Cooperative of Workers…

77 FR 71827 - Notice of Extension of Concession Contracts

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-04

... concession contracts for a period of up to 1 (one) year, or until such time as a new contract is executed, whichever occurs sooner. DATES: Effective Date: January 1, 2013. FOR FURTHER INFORMATION CONTACT: Jo A.... Canyon National Parks. BRCA001-03 Bryce Canyon Natural Bryce Canyon History Association. National Park...

77 FR 25505 - Proposed Submission of Information Collection for OMB Review; Comment Request; Locating and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-30

... Disclosure Division of the Office of the General Counsel of PBGC at the above address or by visiting that... INFORMATION CONTACT: Jo Amato Burns, Attorney, or Catherine B. Klion, Manager, Regulatory and Policy Division..., designating a beneficiary, granting a power of attorney, electing monthly payments, electing to withhold...

78 FR 51189 - Filing Dates for the Alabama Special Elections in the 1st Congressional District

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-20

... 1st Congressional District AGENCY: Federal Election Commission. ACTION: Notice of filing dates for... Congressional District vacated by Representative Jo Bonner. There are three possible special elections, but only... Election, the top two vote-getters will participate in a Special Runoff Election. General Election...

The use of automated weather stations for irrigation management in the Jordan Valley

USDA-ARS?s Scientific Manuscript database

We discuss an irrigation management information system approach developed by NCARE researchers with the help of USDA-ARS. The system is capable of providing farmers with online crop water requirements based on automated meteorological data published on the internet (www.ncare.gov.jo/imis, and www.m...

U.S. EPA, Pesticide Product Label, GRASLAN BRUSH BULLETS 125, 01/13/1983

EPA Pesticide Factsheets

2011-04-14

... r!af"S ;'OP', f· q"l ClnA~LAN E·l.~'" t~~. etc; ':" ·l::n ..... f;' "'J'-o( ~ ,': f:f Il{'f '1"'0 ~"!~.J,ll '''''d. c'aT'1 Ol.! "n rr',:'e Ina"'':O \\.")R",S'-A~. BII.~" t~" j'::;' ...

Supervisory Scratchings: Critical Autoethnography Complicating "Process" in Doctoral Supervision

ERIC Educational Resources Information Center

McKnight, Lucinda; O'Mara, Joanne

2017-01-01

In this dialogic article of interwoven stories, we employ a critical autoethnographic approach to explore moments of our lives as we worked through the official "research plan" at the heart of the supervision timeline. Lucinda's doctoral thesis in education, supervised by Jo, highlights the way curriculum emerges from the struggles of…

Future of Autonomous Ground Logistics: Convoys in the Department of Defense

DTIC Science & Technology

2011-02-13

Driverless van crosses from Europe to Asia, CNN, October 27, 2010, http://edition.cnn.com/2010/TECH/innovation/10/27/driverless.car/ (accessed November 13...accessed March 13, 2011). Kent, Jo Ling. “ Driverless Van Crosses from Europe to Asia,” CNN, October 27, 2010. http://edition.cnn.com/2010/TECH

Illinois Association for Counseling and Development (IACD) Quarterly, 1990.

ERIC Educational Resources Information Center

Illovsky, Michael E., Ed.

1990-01-01

This document consists of the four issues of the "IACD Quarterly" published in 1990. Articles in this volume include: (1) "A Comprehensive Program for Reducing School Anxieties in College Students" (David Ross); (2) "Issues in Child Custody Determination in Illinois" (Amy Jo Buwick); (3) "Finding Meaning in the Here and Now Through Gestalt Therapy…

Viewpoint: The History Manifesto and the History of Science. Editor's Introduction.

PubMed

Cohen, H Floris

2016-06-01

This "Viewpoint" section takes up the question of what, if anything, historians of science can learn from The History Manifesto, initially published in the fall of 2014. One summary, two essay reviews, and nine short comments are followed by remarks by the authors of the manifesto, Jo Guldi and David Armitage.

Workplace Learning Issues. Symposium 31. [AHRD Conference, 2001].

ERIC Educational Resources Information Center

2001

This document contains three papers on workplace learning issues and human resource development. "The Impact of Self-Management on Training Participation" (Jasper B. van Loo, Andries de Guip, Jo G.L. Thijssen) combines HRD and economic theory to in an attempt to explain the relationship between self-management and training participation.…

Pewaukee School District, Wisconsin. Case Study: Measures of Academic Progress

ERIC Educational Resources Information Center

Northwest Evaluation Association, 2015

2015-01-01

For more than a decade, Pewaukee School District Superintendent JoAnn Sternke has watched her district get better and better at its mission: opening the door to each student's future. The Wisconsin district began using Measures of Academic Progress® (MAP®) computer adaptive interim assessments from Northwest Evaluation Association™ (NWEA™) in 2004…

New Systems Produced by Systemic Change

ERIC Educational Resources Information Center

Battino, Wendy; Clem, Jo; Caine, Renate N.; Reigeluth, Charles M.; Chapman, Carrie; Flinders, David J.; Malopinsky, Larissa V.

2006-01-01

This article presents new systems produced by systemic change. First is Systemic Changes in the Chugach School District by Wendy Battino and Jo Clem. Second is Systemic Changes in Public Schools through Brain-Based Learning by Renate N. Caine. Third is A Vision of an Information-Age Educational System by Charles M. Reigeluth. Fourth is Systemic…

Jo Ann Rinaudo, PhD | Division of Cancer Prevention

Cancer.gov

The Division of Cancer Prevention (DCP) conducts and supports research to determine a person's risk of cancer and to find ways to reduce the risk. This knowledge is critical to making progress against cancer because risk varies over the lifespan as genetic and epigenetic changes can transform healthy tissue into invasive cancer.

Determining Pilot Manning for Bomber Longevity

DTIC Science & Technology

2011-03-01

Denny Benson for the MAJCOM analyst guidance and support which he offered and I gladly accepted. Dr. J.O. Miller – thank you sir for teaching me this...December 2002. [14] Kelton, W. David, Randall P Sadowski, and David T Surrock. Simulation with Arena, (4th edition). New York: McGraw-Hill, 2007. 64 [15

Artificial Intelligence Software Acquisition Program. Volume 2.

DTIC Science & Technology

1987-12-01

34Architect tire prototyping in the software engineering environment". 1BBA! .’ qtins Jo urnal, vol. 23, No. 1, p. 4-18, 1984. 3v Boehmi, Barry W_. Gray...on Artificial Intelligence, Sponsored by AAAI, December 1986. ..- ~[31] Pressman , Roger S. "Software Engineering: A Practitioner’s Approach". McGraw

Indigenous Storywork: Educating the Heart, Mind, Body, and Spirit

ERIC Educational Resources Information Center

Archibald, Jo-ann

2008-01-01

Indigenous oral narratives are an important source for, and component of, Coast Salish knowledge systems. Stories are not only to be recounted and passed down; they are also intended as tools for teaching. Jo-ann Archibald worked closely with Elders and storytellers, who shared both traditional and personal life-experience stories, in order to…

75 FR 23745 - Jo-Ann Stores, Inc., Provisional Acceptance of a Settlement Agreement and Order

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-04

..., therefore, are subject to the requirements of the Commission's Ban of Lead-Containing Paint and Certain Consumer Products Bearing Lead-Containing Paint, 16 CFR part 1303 (the ``Lead-Paint Ban''). Under the Lead-Paint Ban, toys and other children's articles must not bear or contain ``lead-containing paint...

Our Visions of Possibility for Literacy

ERIC Educational Resources Information Center

O'Keefe, Tim; Reinier, Rise; Gallagher, Kevin; Morgan, Bruce; Lopez-Robertson, Julia; Santman, Donna; Wong-Kam, JoAnn; Hill, Sharon; Christensen, Linda

2006-01-01

Tim O'Keefe, Rise Reinier and Kevin Gallagher, Bruce Morgan, Julia Lopez-Robertson, Donna Santman, JoAnn Wong-Kam, Sharon Hill, and Linda Christensen provide short essays describing their personal visions of possibility about literacy and how they maintain that passion and vision. Across a range of contexts, they reflect on the ways in which their…

An Evaluation of University World Geography Textbook Questions for Components of Spatial Thinking

ERIC Educational Resources Information Center

Scholz, Michael A.; Huynh, Niem Tu; Brysch, Carmen P.; Scholz, Ruojing Wang

2014-01-01

Geography textbooks contain chapter or review questions that may engage students in spatial thinking. This research used Jo and Bednarz's (2009) "Taxonomy of Spatial Thinking" to evaluate the percentage of spatial thinking questions in four university-level world geography course textbooks. The results from this study were then…

Research and Clinical Center for Child Development Annual Report, 1995-1996, No. 19.

ERIC Educational Resources Information Center

Wakai, Kunio, Ed.; Chen, Shing-Jen, Ed.; Furutsuka, Takashi, Ed.; Shirotani, Yukari, Ed.

This annual report discusses several topics related to the work of the Research and Clinical Center for Child Development at Hokkaido University in Japan. The articles are: (1) "Heart to Heart (Inter "Jo") Resonance: Taking Japanese Concept of Intersubjectivity Out of Everyday Life" (Shigeru Nakano); (2) "Intersubjectivity…

The Chappaquiddick Incident

ERIC Educational Resources Information Center

Cross, Rod

2016-01-01

On July 19, 1969, Senator Edward Kennedy drove his vehicle off a low bridge on Chappaquiddick Island in Massachusetts. The vehicle sank in 2.1 m of water, coming to rest on its roof. According to Kennedy's version of events, he managed to escape from the submerged vehicle without injury, but his female companion, Mary Jo Kopechne, drowned without…

Motivate!

ERIC Educational Resources Information Center

Villano, Matt

2008-01-01

Mary Jo Garcia Biggs never really considered herself much of a technophile. Sure, the assistant professor at Texas State University-San Marcos knew her way around a web page, but for years, she was painfully aware of all of the technologies she didn't know much about. More times than not, the limitations of her knowledge frustrated the heck out of…

Training in Business and Industry. Selected Research Papers, 1995. AERA Special Interest Group.

ERIC Educational Resources Information Center

Mulder, Martin, Ed.

This document contains 7 of the 10 papers presented at the 1995 program of the American Educational Research Association's special interest group, Training in Business and Industry. The following papers are included: "A Multi-Disciplinary Approach to Integrating Evaluation and Training" (Jo D. Gallagher); "Comparing Managers and…

A Portable Burn Pan for the Disposal of Excess Propellants

DTIC Science & Technology

2015-11-01

National Guard Bureau; John Hunt , formerly at Camp Grayling; Jo Anderson, formerly at Ft. Indiantown Gap; and Steve Thurmond, formerly at US Army Alaska...Finally at CRREL, Marianne Walsh, Charlie Smith, Tommie Hall, Matt Bigl, Chris Donnelly, and Jordan Hodge all played major roles in the success of the burn pan.

Structure-based Design of Cdk4/6-Specific Inhibitors

DTIC Science & Technology

2005-10-01

were selected to facilitate interactions with residues in neighboring repeats. Moreover,buried hydrophilic residues were mutated to hydrophobic res- Fio ... Russo , A. A., Tong, L., Lee, J.-O., Jeffrey, P. D., and Pavletich, N. P. (1998) tion, although we do not yet have structures for the p18"NK4c Nature 395

Rare myositis-specific autoantibody associations among Hungarian patients with idiopathic inflammatory myopathy.

PubMed

Bodoki, L; Nagy-Vincze, M; Griger, Z; Betteridge, Z; Szöllősi, L; Jobanputra, R; Dankó, K

2015-01-01

Idiopathic inflammatory myopathies are systemic, chronic autoimmune diseases characterized by symmetrical, proximal muscle weakness. Homogeneous groups present with similar symptoms. The response to therapy and prognosis could be facilitated by myositis-specific autoantibodies, and in this way, give rise to immunoserological classification. The myositis-specific autoantibodies are directed against specific proteins found in the cytoplasm or in the nucleus of the cells. To date, literature suggests the rarity of the co-existence of two myositis-specific autoantibodies. In this study the authors highlight rare associations of myositis-specific autoantibodies. Three hundred and thirty-seven Hungarian patients with polymyositis or dermatomyositis were studied. Their clinical findings were noted retrospectively. Specific blood tests identified six patients with the rare co-existence of myositis-specific autoantibodies, anti-Jo-1 and anti-SRP, anti-Jo-1 and anti-Mi-2, anti-Mi-2 and anti-PL-12, anti-Mi-2 and anti-SRP, and anti-SRP and anti-PL-7, respectively. This case review aims to identify the clinical importance of these rare associations and their place within the immunoserological classification.

Prime Contract Awards Alphabetically by Contractor, by State or Country, and Place. Part 17 (Ray Industries-Service Screw Company Inc)

DTIC Science & Technology

1990-01-01

044 (0N (0NI 00.10 ON C 0 -4 OCN 01) 0le "OfE Zz1-ZM a t=000)@ V) cm -4 C.)r-’ WtC4-11VRI IN r-00 ?NC il o an ~wO.il- a 0000 0 CO a 000 000" Coca ...6I-40" 6-L) 6-I 6l -40) 1-10) Cc 11-b6(0c-4 itJ0( .. J coca NNN -JO -.JN 4J0( CSI5(0m - -JO -100 ...Jco C6to (0 M-I4 I (00x (0003C.>a c oC co (00 (0x...4-0 N .4 4 4 -4 -1 C’J cli 17) on . . . 17) 17) (U ttnt M I.L. < 1.1- LAJ UJ W LLJ 161- < M < to M < <<< 0 a < I.)) CCIJI of M M coca M 0 0z 0z 0:1- 0

The reporting quality of randomized controlled trials in orthodontics.

PubMed

Lempesi, Evangelia; Koletsi, Despina; Fleming, Padhraig S; Pandis, Nikolaos

2014-06-01

Accurate trial reporting facilitates evaluation and better use of study results. The objective of this article is to investigate the quality of reporting of randomized controlled trials (RCTs) in leading orthodontic journals, and to explore potential predictors of improved reporting. The 50 most recent issues of 4 leading orthodontic journals until November 2013 were electronically searched. Reporting quality assessment was conducted using the modified CONSORT statement checklist. The relationship between potential predictors and the modified CONSORT score was assessed using linear regression modeling. 128 RCTs were identified with a mean modified CONSORT score of 68.97% (SD = 11.09). The Journal of Orthodontics (JO) ranked first in terms of completeness of reporting (modified CONSORT score 76.21%, SD = 10.1), followed by American Journal of Orthodontics and Dentofacial Orthopedics (AJODO) (73.05%, SD = 10.1). Journal of publication (AJODO: β = 10.08, 95% CI: 5.78, 14.38; JO: β = 16.82, 95% CI: 11.70, 21.94; EJO: β = 7.21, 95% CI: 2.69, 11.72 compared to Angle), year of publication (β = 0.98, 95% CI: 0.28, 1.67 for each additional year), region of authorship (Europe: β = 5.19, 95% CI: 1.30, 9.09 compared to Asia/other), statistical significance (significant: β = 3.10, 95% CI: 0.11, 6.10 compared to non-significant) and methodologist involvement (involvement: β = 5.60, 95% CI: 1.66, 9.54 compared to non-involvement) were all significant predictors of improved modified CONSORT scores in the multivariable model. Additionally, median overall Jadad score was 2 (IQR = 2) across journals, with JO (median = 3, IQR = 1) and AJODO (median = 3, IQR = 2) presenting the highest score values. The reporting quality of RCTs published in leading orthodontic journals is considered suboptimal in various CONSORT areas. This may have a bearing in trial result interpretation and use in clinical decision making and evidence- based orthodontic treatment interventions. Copyright © 2014 Elsevier Inc. All rights reserved.

Acute exercise alters skeletal muscle mitochondrial respiration and H2O2 emission in response to hyperinsulinemic-euglycemic clamp in middle-aged obese men

PubMed Central

Trewin, Adam J.; Levinger, Itamar; Parker, Lewan; Shaw, Christopher S.; Serpiello, Fabio R.; Anderson, Mitchell J.; McConell, Glenn K.; Hare, David L.

2017-01-01

Obesity, sedentary lifestyle and aging are associated with mitochondrial dysfunction and impaired insulin sensitivity. Acute exercise increases insulin sensitivity in skeletal muscle; however, whether mitochondria are involved in these processes remains unclear. The aim of this study was to investigate the effects of insulin stimulation at rest and after acute exercise on skeletal muscle mitochondrial respiratory function (JO2) and hydrogen peroxide emission (JH2O2), and the associations with insulin sensitivity in obese, sedentary men. Nine men (means ± SD: 57 ± 6 years; BMI 33 ± 5 kg.m2) underwent hyperinsulinemic-euglycemic clamps in two separate trials 1–3 weeks apart: one under resting conditions, and another 1 hour after high-intensity exercise (4x4 min cycling at 95% HRpeak). Muscle biopsies were obtained at baseline, and pre/post clamp to measure JO2 with high-resolution respirometry and JH2O2 via Amplex UltraRed from permeabilized fibers. Post-exercise, both JO2 and JH2O2 during ADP stimulated state-3/OXPHOS respiration were lower compared to baseline (P<0.05), but not after subsequent insulin stimulation. JH2O2 was lower post-exercise and after subsequent insulin stimulation compared to insulin stimulation in the rest trial during succinate supported state-4/leak respiration (P<0.05). In contrast, JH2O2 increased during complex-I supported leak respiration with insulin after exercise compared with resting conditions (P<0.05). Resting insulin sensitivity and JH2O2 during complex-I leak respiration were positively correlated (r = 0.77, P<0.05). We conclude that in obese, older and sedentary men, acute exercise modifies skeletal muscle mitochondrial respiration and H2O2 emission responses to hyperinsulinemia in a respiratory state-specific manner, which may have implications for metabolic diseases involving insulin resistance. PMID:29161316

Growth in elevated CO(2) can both increase and decrease photochemistry and photoinhibition of photosynthesis in a predictable manner. Dactylis glomerata grown in two levels of nitrogen nutrition.

PubMed

Hymus, G J; Baker, N R; Long, S P

2001-11-01

Biochemically based models of C(3) photosynthesis can be used to predict that when photosynthesis is limited by the amount of Rubisco, increasing atmospheric CO(2) partial pressure (pCO(2)) will increase light-saturated linear electron flow through photosystem II (J(t)). This is because the stimulation of electron flow to the photosynthetic carbon reduction cycle (J(c)) will be greater than the competitive suppression of electron flow to the photorespiratory carbon oxidation cycle (J(o)). Where elevated pCO(2) increases J(t), then the ratio of absorbed energy dissipated photochemically to that dissipated non-photochemically will rise. These predictions were tested on Dactylis glomerata grown in fully controlled environments, at either ambient (35 Pa) or elevated (65 Pa) pCO(2), and at two levels of nitrogen nutrition. As was predicted, for D. glomerata grown in high nitrogen, J(t) was significantly higher in plants grown and measured at elevated pCO(2) than for plants grown and measured at ambient pCO(2). This was due to a significant increase in J(c) exceeding any suppression of J(o). This increase in photochemistry at elevated pCO(2) protected against photoinhibition at high light. For plants grown at low nitrogen, J(t) was significantly lower in plants grown and measured at elevated pCO(2) than for plants grown and measured at ambient pCO(2). Elevated pCO(2) again suppressed J(o); however growth in elevated pCO(2) resulted in an acclimatory decrease in leaf Rubisco content that removed any stimulation of J(c). Consistent with decreased photochemistry, for leaves grown at low nitrogen, the recovery from a 3-h photoinhibitory treatment was slower at elevated pCO(2).

Towards a Theory of Identity and Agency in Coming to Learn Mathematics

ERIC Educational Resources Information Center

Grootenboer, Peter; Jorgensen, Robyn

2009-01-01

In writing this paper we draw considerably on the work of Jo Boaler and Leone Burton. Boaler's studies of classrooms have been particularly poignant in alerting the mathematics education community to a number of key features of successful classrooms, and how such features can turn around the successes for students who traditionally perform poorly…

Pair-List Readings in Korean-Japanese, Chinese-Japanese and English-Japanese Interlanguage

ERIC Educational Resources Information Center

Marsden, Heather

2008-01-01

In English and Chinese, questions with a "wh"-object and a universally quantified subject (e.g. "What did everyone buy?") allow an individual answer ("Everyone bought apples.") and a pair-list answer ("Sam bought apples, Jo bought bananas, Sally bought..."). By contrast, the pair-list answer is reportedly unavailable in Japanese and Korean. This…

Literacy Development in the First Year of Schooling.

ERIC Educational Resources Information Center

Hill, Susan; Louden, William

Drawing on the research study, "100 Children Go to School: Connections between Literacy Development in the Prior to School Period and the First Year of Schooling," conducted from 1996-1998 by a team made up of Susan Hill, Barbara Comber, William Louden, Judith Rivalland, and Jo-Anne Reid, this paper discusses the findings of the study,…

75 FR 54942 - Agency Information Collection Activities: Requests for Comments; Clearance of a New Approval of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-09

... intention to request the Office of Management and Budget (OMB) approval for a new information collection. In accordance with FAA Order JO 1030.4, ATO SysOps Services SMS Oversight, the FAA ATO System Operations Management, Safety Assurance Group (SAG) is conducting a comprehensive assessment of the Notice to Airmen...

76 FR 9400 - Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-17

... intention to request the Office of Management and Budget (OMB) approval for a new information collection... accordance with FAA Order JO 1030.4, ATO SysOps Services SMS Oversight, the FAA ATO System Operations Management, Safety Assurance Group (SAG) is conducting an assessment of the Notice to Airmen (NOTAM...

Intensive Survey at 11-Jd-126, Jo Daviess County, Illinois. Volume 3. Data Sheets.

DTIC Science & Technology

1983-07-01

RECORDER: P. Lurenz, Jr. H NOWO DATE:_ _____ V__Level 2 FEATURE______ DATE: 9/82 COLL#_______ 1 23 45 678919 0111 2 13 Total Sherds Rim temper1 Grt Rim...thickness in millimeters LITHIC INVENTORY - 347 - SITE# 11Jd126 LOT# 80 RECORDER: P. Lurenz, Jr. H_______________ DATE: November, 1982 V_______ FEATURE

The Politics of "Crazy-Making" and Control: A Reform Teacher's Perspective

ERIC Educational Resources Information Center

Marchese, Stephanie Jo

2017-01-01

As a young educator, Stephanie Jo Marchese was initially emboldened by hope and naivety. However, trying to balance the resistance to her body politics and the rules of engagement forced upon her in schools set the stage for an inevitable collision. She faced the devastating reality that a Queer-White-Radical-Feminist-Survivor-Teacher heralding…

Precision Atomic Beam Spectroscopy Using Stabilized Lasers.

DTIC Science & Technology

1985-06-30

spacer (a Zerodur rod 15 cm dia. by 30 cm length) under ir I MN, M A 9 differentials of its own weight. A powerful tilt stabilization concept has been...1120-2523 (1936). 3504. Jo L. Hell, No Len -Sheng and G. Kramer,’Prinuiples of *ptical phase lock ng: :ith eppr catien to internal mirror Ne-o