Effect of erbium ion concentration on structural and luminescence properties of lead borosilicate glasses for fiber amplifiers.

This investigation reports, the effect of the concentration of erbium and lead ions on the physical, structural and optical properties of lead borosilicate glasses. These glasses were synthesized by the melt quench method. In the synthesis, the concentration of the erbium (Er3+ ) ion was varied in the order of 0.0, 0.1, 0.5, 1.0 and 2.0 mol% and lead (Pb2+ ) ion was varied in the order of 30, 29.9, 29.5, 29 and 28 mol%. The glasses were analyzed using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and UV-vis-NIR spectroscopy. From XRD, the amorphous nature of lead borosilicate glasses was confirmed. The functional groups which were present in the glasses have been identified by analyzing the FT-IR spectrum. From the absorption spectra, the oscillator strengths as well as the Judd-Ofelt (JO) intensity parameters were determined and compared with other hosts. The JO intensity parameters were further used to calculate certain radiative properties for the excited luminescent levels of Er3+ ion. From emission spectra, full width at half maxima (FWHM), stimulated emission cross-sections (σe ) and certain lasing parameters were evaluated and compared with reference host glasses. The lifetimes of 4 I13/2 excited level of Er3+ ion have also been recorded and analyzed. The calculated and experimental lifetimes were compared in terms of quantum efficiencies. From the photoluminescence analysis, the erbium doped lead borosilicate glasses well suited for optical fiber amplifiers are discussed.

Nano-level monitoring of Er(III) by fabrication of coated graphite electrode based on newly synthesized Schiff base as neutral carrier.

Plasticized membranes using N-(-3-((thiazol-2-ylimino)methyl)benzylidene)thiazol-2-amine (S1) and 5-((-3-((5-mercapto-1,3,4-thiadiazol-2-ylimino)methyl)benzylidene)amino)-1,3,4-thiadiazole-2-thiol (S2) have been prepared and explored as Er (III) selective electrodes. Effect of various plasticizers viz. dibutylphthalate, tri-n-butylphosphate, dioctylphthalate, acetophenone, 1-chloronapthalene, o-nitrophenyloctylether, and anion excluders viz. sodium tetraphenylborate and potassium tetrakis-p-(chlorophenyl)borate was studied in detail and improved performance was observed. Optimum performance was observed for the membrane electrode having a composition of S2: PVC: o-NPOE: KTpClPB in the ratio of 4: 38: 55: 3 (w/w, mg). The performance of the PME based on S2 was compared with CGE. The electrodes exhibit Nernstian slope for Er (III) ion with detection limit 5.4 × 10(-8)mol L(-1) for PME and 6.1 × 10(-9)mol L(-1) for CGE. The response time for PME and CGE was found to be 12s and 9s respectively. The practical utility of the CGE has been demonstrated by its usage as an indicator electrode in potentiometric titration of EDTA with Er (III) solution and determination of fluoride ions in mouthwash solution. The proposed electrode was also applied to the determination of added Er(3+) ion in water and binary mixtures. It is found that the electrode could be able to recover the Er(3+) ion in 96.2-99.5%.

Combined spectral experiment and theoretical calculation to study the interaction of 1,4-dihydroxyanthraquinone for metal ions in solution.

The interaction between 1,4-dihydroxyanthraquinone (1,4-DHA) and metal ions was studied by UV-Visible and fluorescence spectroscopies in solution. Time-dependent density functional theory calculations confirmed complex structures. The investigation results showed 1,4-DHA can selectively respond some metal ions and can be monitored by UV-Vis, fluorescence spectra and naked-eye. So 1,4-DHA has a potential application in the design of metal ions probe. More, as typical metal ions, Hg(2+) and Er(3+), their reaction abilities for 1,4-DHA were studied in detailed. Experimental results showed they have better response for 1,4-DHA. And theoretical calculation concluded that Er(3+) easily reacts with 1,4-DHA over Hg(2+) attributed to the low reaction energy of Er(3+)-1,4-DHA than Hg(2+)-1,4-DHA.

Biological dosimetry after radiosynoviorthesis with rhenium-186 sulphide and erbium-169 citrate.

UNLABELLED: Radiosynoviorthesis (RSO) with the nuclides rhenium-186 sulphide (186Re) and erbium-169 citrate (169Er) is an established concept for the treatment of persistent synovitis of medium and small sized joints. THE AIM of the present studies was to investigate the biological radiation effect based on analysing chromosome aberrations. PATIENTS, METHODS: Immediately before and 17 to 19 days (186Re) or 45 to 50 (169Er) days after RSO with 186Re or 169Er colloid and subsequent immobilisation of the treated joint, blood samples of a total of 23 patients were collected. The yield of dicentric chromosomes in lymphocytes was determined exclusively in metaphases of the first cell cycle in vitro. In addition, for 186Re the activity leakage was measured three days after RSO by whole-body scintigraphy. RESULTS: No statistically significant increase in the number of dicentric chromosomes (40 and 88 before and 59 and 105 after treatment with 186Re and 169Er, respectively) in a total of 47017 cells analysed from 46 blood samples could be found as a result of RSO. For 186Re an activity leakage of 3.9%±7% with a maximum of 23.4% corresponding to an effective dose of 2.8±4.5 mSv , respectively 13.8 mSv, was determined. Also in the case of the maximum leakage no significant increase of dicentric chromosomes were detected. CONCLUSIONS: No significant biological radiation effect can be detected after RSO with 186Re and 169Er, also in cases of high leakage. Therefore, RSO can be classified as a save therapeutic procedure without a relevant radiation risk.

Sorption of lanthanum and erbium from aqueous solution by activated carbon prepared from rice husk.

A biomass agricultural waste material, rice husk (RH) was used for preparation of activated carbon by chemical activation using phosphoric acid. The effect of various factors, e.g. time, pH, initial concentration and temperature of carbon on the adsorption capacity of lanthanum and erbium was quantitatively determined. It was found that the monolayer capacity is 175.4 mg g(-1) for La(III) and 250 mg g(-1) for Er(III). The calculated activation energy of La(III) adsorption on the activated carbon derived from rice husk was equal to 5.84 kJ/mol while it was 3.6 kJ/mol for Er(III), which confirm that the reaction is mainly particle-diffusion-controlled. The kinetics of sorption was described by a model of a pseudo-second-order. External diffusion and intra-particular diffusion were examined. The experimental data show that the external diffusion and intra-particular diffusion are significant in the determination of the sorption rate. Therefore, the developed sorbent is considered as a better replacement technology for removal of La(III) and Er(III) ions from aqueous solution due to its low-cost and good efficiency, fast kinetics, as well as easy to handle and thus no or small amount of secondary sludge is obtained in this application.

The effect of erbium on the adsorption and photodegradation of orange I in aqueous Er3+-TiO2 suspension.

Pure TiO(2) and erbium ion-doped TiO(2) (Er(3+)-TiO(2)) catalysts prepared by the sol-gel method were characterized by means of XRD and diffusive reflectance spectra (DRS). The XRD results showed that erbium ion doping could enhance the thermal stability of TiO(2) and inhibit the increase of the crystallite size, and the DRS results showed that the optical absorption edge slightly shifted to red direction owing to erbium ion doping and the Er(3+)-TiO(2) catalysts had three typical absorption peaks located at 490, 523 and 654 nm owing to the transition of 4f electron from (4)I(15/2) to (4)F(7/2), (2)H(11/2) and (4)F(9/2). With a purpose of azo dyes degradation, orange I was used as a model chemical. And the adsorption isotherm, degradation and mineralization of orange I were investigated in aqueous suspension of pure TiO(2) or Er(3+)-TiO(2) catalysts. The results showed that Er(3+)-TiO(2) catalysts had higher adsorption equilibrium constants and better adsorption capacity than pure TiO(2). The adsorption equilibrium constants (K(a)) of Er(3+)-TiO(2) catalysts were about twice of that of pure TiO(2). The maximum adsorption capacity (Q(max)) of 2.0% Er(3+)-TiO(2) catalyst was 13.08x10(-5)mol/g, which was much higher than that of pure TiO(2) with 9.03x10(-5)mol/g. Among Er(3+)-TiO(2) catalysts, 2.0% Er(3+)-TiO(2) catalyst achieved the highest Q(max) and K(a) values. The kinetics of the orange I degradation using different Er(3+)-TiO(2) catalysts were also studied. The results demonstrated that the degradation and mineralization of orange I under both UV radiation and visible light were more efficient with Er(3+)-TiO(2) catalyst than with pure TiO(2), and an optimal dosage of erbium ion at 1.5% achieved the highest degradation rate. The higher photoactivity under visible light might be attributable to the transitions of 4f electrons of Er(3+) and red shifts of the optical absorption edge of TiO(2) by erbium ion doping.

Lowest limit for detection of impurity concentration in semiconductors by fluorescence XAFS: resonant Raman scattering and angle dependence.

The lowest limit for detection (LLD) of the impurity concentration doped in semiconductors in the case of fluorescence XAFS measurements has been investigated as a function of the matrix of the impurity and the geometry of the measurement. When the impurity concentration is very low and other background noise is well suppressed, X-ray resonant Raman scattering by the constituent atoms of the matrix remains as a major background for the fluorescence-detected XAFS measurement. For example, in the fluorescence-detected XAFS measurement for Er-doped semiconductors at the Er L(III)-edge, the LLD of the Er concentration was about 5 x 10(14) to 1 x 10(15) cm(-2) for GaAs and GaP, and lower than 1 x 10(14) cm(-2) for InP. The resonant Raman scattering of Ga atoms in the host semiconductor determines the LLD.

Manufacture and properties of erythromycin beads containing neutron-activated erbium-171.

To evaluate the effects of a neutron activation radiolabeling technique on an enteric-coated multiparticulate formulation of erythromycin, test quantities were produced under industrial pilot scale conditions. The pellets contained the stable isotope erbium oxide (Er-170), which was later converted by neutron activation into the short-lived gamma ray-emitting radionuclide, erbium-171. In vitro studies indicated that the dissolution profile, acid resistance, and enteric-coated surface of the pellets were minimally affected by the irradiation procedure. Antimicrobial potency was also unaffected, as determined by microbiological assay. Neutron activation thus appears to simplify the radiolabeling of complex pharmaceutical dosage forms for in vivo study by external gamma scintigraphy.

A preliminary ferrographic survey of the wear particles in human synovial fluid.

The technique of ferrography has been applied to the analysis of wear particles in human synovial fluid aspirates. A number of discrete, identifiable classes of wear particles were found, including particles indicative of cutting wear and rubbing wear. The spectrum of particles varied among different groups of patients, suggesting an eventual diagnostic use for this method.