WorldWideScience

Sample records for europium 156

  1. Fluorescent Europium Chelate Stain

    Science.gov (United States)

    Scaff, W. L.; Dyer, D. L.; Mori, K.

    1969-01-01

    The europium chelate of 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione (thenoyl-trifluoroacetone; TTA) is firmly bound to microorganisms. It fluoresces brightly at 613 nm with activation at 340 nm. Cells may be stained with 10−3m chelate in 50% ethyl alcohol, followed by washing with 50% ethyl alcohol. Equal or better stains are produced with 10−3m aqueous europium salt, water wash, and 10−2m aqueous TTA. A noncomplexing buffer should be used to maintain the pH at 6.5 to 6.8. Images PMID:4181107

  2. Europium-155 in Debris from Nuclear Weapons

    DEFF Research Database (Denmark)

    Aarkrog, Asker; Lippert, Jørgen Emil

    1967-01-01

    The lithium-drifted germanium detector enables determination of europium-155 on a routine basis in environmental samples contaminated with debris from nuclear weapons. From measurements of europium-155, cesium-144, and strontium-90 in air filters collected between 1961 and 1966, the yield...... of europium-155 from weapons was estimated at 1400 atoms per 10$^{6}$ fissions, which is close to the yield of europium-155 from fast fission of uranium-238....

  3. The electrochemical synthesis of europium boride

    Directory of Open Access Journals (Sweden)

    Bukatova G.A.

    2003-01-01

    Full Text Available The electroreduction of boron, europium and the electrochemical synthesis of europium boride have been investigated in NaCl-KCl-NaF(10 wt. % melt on silver and molybdenum electrodes. The parameters of boron reduction in the chloride-fluoride melt have been obtained and the character of its joint deposition with europium has been studied.

  4. The electrochemical synthesis of europium boride

    OpenAIRE

    Bukatova G.A.; Kuznetsov S.A.; Gaune-Escard M.

    2003-01-01

    The electroreduction of boron, europium and the electrochemical synthesis of europium boride have been investigated in NaCl-KCl-NaF(10 wt. %) melt on silver and molybdenum electrodes. The parameters of boron reduction in the chloride-fluoride melt have been obtained and the character of its joint deposition with europium has been studied.

  5. Liposome Biodistribution via Europium Complexes.

    Science.gov (United States)

    Mignet, Nathalie; Scherman, Daniel

    2017-01-01

    The drug delivery field needs tools to follow vector biodistribution. Radioactive tracers and conventional fluorophores are widely used. We propose here to use europium complexes. Use of pulsed light source time-resolved fluorimetry takes into account the fluorescence decay time of the lanthanide chelates to gain sensitivity in biological media. The method was developed to follow liposome biodistribution. Octadecyl-DTPA.Eu compound has been prepared and incorporated into liposomes without alteration of its fluorescence signal. The method has been validated by comparison with fluorophore-labeled liposomes. The way to proceed to use this method for liposomes or other vectors is detailed.

  6. Resonance ionization scheme development for europium

    CERN Document Server

    Chrysalidis, K; Fedosseev, V N; Marsh, B A; Naubereit, P; Rothe, S; Seiffert, C; Kron, T; Wendt, K

    2017-01-01

    Odd-parity autoionizing states of europium have been investigated by resonance ionization spectroscopy via two-step, two-resonance excitations. The aim of this work was to establish ionization schemes specifically suited for europium ion beam production using the ISOLDE Resonance Ionization Laser Ion Source (RILIS). 13 new RILIS-compatible ionization schemes are proposed. The scheme development was the first application of the Photo Ionization Spectroscopy Apparatus (PISA) which has recently been integrated into the RILIS setup.

  7. Resonance ionization scheme development for europium

    Energy Technology Data Exchange (ETDEWEB)

    Chrysalidis, K., E-mail: katerina.chrysalidis@cern.ch; Goodacre, T. Day; Fedosseev, V. N.; Marsh, B. A. [CERN (Switzerland); Naubereit, P. [Johannes Gutenberg-Universität, Institiut für Physik (Germany); Rothe, S.; Seiffert, C. [CERN (Switzerland); Kron, T.; Wendt, K. [Johannes Gutenberg-Universität, Institiut für Physik (Germany)

    2017-11-15

    Odd-parity autoionizing states of europium have been investigated by resonance ionization spectroscopy via two-step, two-resonance excitations. The aim of this work was to establish ionization schemes specifically suited for europium ion beam production using the ISOLDE Resonance Ionization Laser Ion Source (RILIS). 13 new RILIS-compatible ionization schemes are proposed. The scheme development was the first application of the Photo Ionization Spectroscopy Apparatus (PISA) which has recently been integrated into the RILIS setup.

  8. Electronic state of europium atoms on surface of oxidized tungsten

    CERN Document Server

    Davydov, S Y

    2001-01-01

    The energy scheme of the europium atoms adsorption system on the tungsten surface, coated with the oxygen monolayer, is considered. The evaluations of the europium adatoms charged state on the oxidized tungsten surface are performed. It is established, that europium, adsorbed at the oxidized tungsten surface, is a positive ion with the charge close to the unit. The zonal scheme of the Eu-O/W adsorption system for the europium low and high concentrations is proposed

  9. Europium anomaly in plagioclase feldspar - Experimental results and semiquantitative model.

    Science.gov (United States)

    Weill, D. F.; Drake, M. J.

    1973-01-01

    The partition of europium between plagioclase feldspar and magmatic liquid is considered in terms of the distribution coefficients for divalent and trivalent europium. A model equation is derived giving the europium anomaly in plagioclase as a function of temperature and oxygen fugacity. The model explains europium anomalies in plagioclase synthesized under controlled laboratory conditions as well as the variations of the anomaly observed in natural terrestrial and extraterrestrial igneous rocks.

  10. Fermi Surface and Antiferromagnetism in Europium Metal

    DEFF Research Database (Denmark)

    Andersen, O. Krogh; Loucks, T. L.

    1968-01-01

    We have calculated the Fermi surface of europium in order to find those features which determine the wave vector of the helical moment arrangement below the Néel point. We find that there are two pieces of Fermi surface: an electron surface at the symmetry point H, which has the shape of rounded...... of the nearly cubical part of the hole surface at P, and we also discuss the effects of the electron surface at H. Since it is likely that barium and europium have similar Fermi surfaces, we have presented several extremal areas and the corresponding de Haas-van Alphen frequencies in the hope that experimental...

  11. Organophosphate Nerve Agent Detection with Europium Complexes

    Directory of Open Access Journals (Sweden)

    Jake R. Schwierking

    2004-01-01

    Full Text Available We explore the detection of paraoxon, a model compound for nonvolatile organophosphate nerve agents such as VX. The detection utilizes europium complexes with 1,10 phenanthroline and thenoyltrifluoroacetone as sensitizing ligands. Both europium luminescence quenching and luminescence enhancement modalities are involved in the detection, which is simple, rapid, and sensitive. It is adaptable as well to the more volatile fluorophosphate nerve agents. It involves nothing more than visual luminescence observation under sample illumination by an ordinary hand-held ultraviolet lamp.

  12. Europium enabled luminescent nanoparticles for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Syamchand, S.S., E-mail: syamchand.ss@gmail.com; Sony, G., E-mail: emailtosony@gmail.com

    2015-09-15

    Lanthanide based nanoparticles are receiving great attention ought to their excellent luminescent and magnetic properties and find challenging biomedical applications. Among the luminescent lanthanide NPs, europium based NPs (Eu-NPs) are better candidates for immunoassay and imaging applications. The Eu-NPs have an edge over quantum dots (QDs) by means of their stable luminescence, long fluorescence lifetime, sharp emission peaks with narrow band width, lack of blinking and biocompatibility. This review surveys the synthesis and properties of a variety of Eu-NPs consolidated from different research articles, for their applications in medicine and biology. The exquisite luminescent properties of Eu-NPs are explored for developing biomedical applications such as immunoassay and bioimaging including multimodal imaging. The biomedical applications of Eu-NPs are mostly diagnostic in nature and mainly focus on various key analytes present in biological systems. The luminescent properties of europium enabled NPs are influenced by a number of factors such as the site symmetry, the metal nanoparticles, metal ions, quantum dots, surfactants, morphology of Eu-NPs, crystal defect, phenomena like antenna effect and physical parameters like temperature. Through this review we explore and assimilate all the factors which affect the luminescence in Eu-NPs and coil a new thread of parameters that control the luminescence in Eu-NPs, which would provide further insight in developing Eu-based nanoprobes for future biomedical prospects. - Highlights: • The review describes 14 major factors that influence the luminescence properties of europium enabled luminescent nanoparticles (Eu-NPs). • Surveys different types of europium containing nanoparticles that have been reported for their biomedical applications. • Eu-NPs are conveniently divided into four different categories, based on the type of the substrates involved. The four categories are (1) virgin Eu-substrate based NPs; (2

  13. The Europium Oxybarometer: Power and Pitfalls

    Science.gov (United States)

    McKay, G.

    2004-01-01

    One of the most important characteristics of a planet is the oxidation state of its mantle, as reflected in primitive basalts. Petrologists have devised several methods to estimate the oxygen fugacity under which basalts crystallized. One method that has been the subject of recent interest involves the depth of the Eu anomaly in first-crystallizing minerals. A discussion detailing the experimental calibration of the Europium oxybarometer and the application of this device to Angrites and Martian basaltic meteorites are presented. The strengths and weaknesses of the instrument are also included.

  14. 47 CFR 69.156 - Marketing expenses.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Marketing expenses. 69.156 Section 69.156... Computation of Charges for Price Cap Local Exchange Carriers § 69.156 Marketing expenses. Effective July 1, 2000, the marketing expenses formerly allocated to the common line and traffic sensitive baskets, and...

  15. 7 CFR 4287.156 - Protective advances.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Protective advances. 4287.156 Section 4287.156... Loans § 4287.156 Protective advances. Protective advances are advances made by the lender for the... meet its obligations. Sound judgment must be exercised in determining that the protective advance...

  16. 32 CFR 156.4 - Responsibilities.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Responsibilities. 156.4 Section 156.4 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE SECURITY DEPARTMENT OF DEFENSE PERSONNEL SECURITY PROGRAM (DoDPSP) § 156.4 Responsibilities. (a) The Assistant Secretary of Defense for Command...

  17. 32 CFR 156.1 - Purpose.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Purpose. 156.1 Section 156.1 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE SECURITY DEPARTMENT OF DEFENSE PERSONNEL SECURITY PROGRAM (DoDPSP) § 156.1 Purpose. This part: (a) Updates the policy and responsibilities for the DoDPSP...

  18. 46 CFR 502.156 - Evidence admissible.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 9 2010-10-01 2010-10-01 false Evidence admissible. 502.156 Section 502.156 Shipping...; Presiding Officers; Evidence § 502.156 Evidence admissible. In any proceeding under the rules in this part, all evidence which is relevant, material, reliable and probative, and not unduly repetitious or...

  19. 21 CFR 156.145 - Tomato juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Tomato juice. 156.145 Section 156.145 Food and... CONSUMPTION VEGETABLE JUICES Requirements for Specific Standardized Vegetable Juices § 156.145 Tomato juice. (a) Identity—(1) Definition. Tomato juice is the food intended for direct consumption, obtained from...

  20. 20 CFR 655.156 - Recruitment report.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Recruitment report. 655.156 Section 655.156... the United States (H-2A Workers) Post-Acceptance Requirements § 655.156 Recruitment report. (a) Requirements of a recruitment report. The employer must prepare, sign, and date a written recruitment report...

  1. 40 CFR 96.156 - Account error.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Account error. 96.156 Section 96.156... Tracking System § 96.156 Account error. The Administrator may, at his or her sole discretion and on his or her own motion, correct any error in any CAIR NOX Allowance Tracking System account. Within 10...

  2. Europium Effect on the Electron Transport in Graphene Ribbons

    Energy Technology Data Exchange (ETDEWEB)

    Bobadilla, Alfredo D.; Ocola, Leonidas E.; Sumant, Anirudha V.; Kaminski, Michael; Kumar, Narendra; Seminario, Jorge M.

    2015-10-01

    We report in this complementary theoretical-experimental work the effect of gating on the election transport of grapheme ribbons when exposed to very low concentration of europium in an aqueous solution. We find a direct correlation between the level of concentration of europium ions in the solvent and the change in electron transport in graphene, observing a change of up to 3 orders of magnitude at the lowest level of concentration tested (0.1 mM), suggesting a possibility that graphene ribbons can be used for detecting very low concentrations of europium in liquid solutions.

  3. Paramagnetic Europium Salen Complex and Sickle-Cell Anemia

    Science.gov (United States)

    Wynter, Clive I.; Ryan, D. H.; May, Leopold; Oliver, F. W.; Brown, Eugene; Hoffman, Eugene J.; Bernstein, David

    2005-04-01

    A new europium salen complex, Eu(salen)2NH4, was synthesized, and its composition was confirmed by chemical analysis and infrared spectroscopy. Further characterization was carried out by 151 Eu Mössbauer spectroscopy and magnetic susceptibility measurements. Mössbauer spectroscopic measurements were made at varying temperatures between 9 K and room temperature and a value of Debye temperature of 133 ±5 K was computed. Both Mössbauer and magnetic susceptibility measurements confirmed the paramagnetic behavior of this complex and the trivalent state of the europium ion. In view of the fact that the "odd" paramagnetic molecule NO has been shown to reverse sickling of red blood cells in sickle cell anemia, the interaction between the paramagnetic europium salen complex and sickle cells was examined after incubation with this europium complex and shown to have similar effects.

  4. Europium polyoxometalates encapsulated in silica nanoparticles - characterization and photoluminescence studies

    Energy Technology Data Exchange (ETDEWEB)

    Neves, Cristina S.; Granadeiro, Carlos M.; Cunha-Silva, Luis; Eaton, Peter; Balula, Salete S.; Pereira, Eulalia [REQUIMTE/Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto (Portugal); Ananias, Duarte [CICECO, Departamento de Quimica, Universidade de Aveiro (Portugal); Gago, Sandra [REQUIMTE, Departamento de Quimica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Monte de Caparica (Portugal); Feio, Gabriel [CENIMAT/I3N, Departamento de Ciencia dos Materiais, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Monte de Caparica (Portugal); Carvalho, Patricia A. [ICEMS/Departamento de Bioengenharia, Instituto Superior Tecnico, Lisboa (Portugal)

    2013-06-15

    The incorporation of europium polyoxometalates into silica nanoparticles can lead to a biocompatible nanomaterial with luminescent properties suitable for applications in biosensors, biological probes, and imaging. Keggin-type europium polyoxometalates Eu(PW{sub 11}){sub x} (x = 1 and 2) with different europium coordination environments were prepared by using simple methodologies and no expensive reactants. These luminescent compounds were then encapsulated into silica nanoparticles for the first time through the water-in-oil microemulsion methodology with a nonionic surfactant. The europium polyoxometalates and the nanoparticles were characterized by using several techniques [FTIR, FT-Raman, {sup 31}P magic angle spinning (MAS) NMR, and TEM/energy-dispersive X-ray spectroscopy (TEM-EDS), AFM, dynamic light scattering (DLS), and inductively coupled plasma MS (ICP-MS) analysis]. The stability of the material and the integrity of the europium compounds incorporated were also examined. Furthermore, the photoluminescence properties of the Eu(PW{sub 11}){sub x} rate at SiO{sub 2} nanomaterials were evaluated and compared with those of the free europium polyoxometalates. The silica surface of the most stable nanoparticles was successfully functionalized with appropriate organosilanes to enable the covalent binding of oligonucleotides. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Spectral Properties of a bis-Azospiropyran Complexed with Europium

    Science.gov (United States)

    Nourmohammadian, F.; Ghahari, M.; Gholami, M. Davoudzadeh

    2015-09-01

    The complexation of recently synthesized symmetrical bifunctional bis-azospiropyran photochromic dye with europium nitrate and its effect on UV-vis absorption and fluorescent emission was studied. Upon addition of Eu 3+ to colorless spiropyran, a yellow merocyanine europium complex was obtained with an absorption band at 410 nm. Negatively charged phenolic oxygenin zwitterionic ring-open form provides an effective metal binding site for Eu 3+ . Meanwhile, the inherent fluorescence emission of the photochromic dye at 380 nm is switched off due to the Eu 3+ - induced drive of spiro-mero equilibrium to form mero form. The stoichiometry of dye-europium complexation was evaluated by fluorescence emission and UV-vis absorption spectroscopy and a 8:1 ratio was obtained in both cases. The binding constant (K) value of the dye-europium complex was 3 × 106 M -1 . In conclusion, the current molecular switch is a useful sensitive dual measuring tool for solutions containing europium or europium-like elements by evaluation of visible absorption or fluorescent emission spectroscopy.

  6. Metal plasmon enhanced europium complex luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Liu Feng [Department of Chemistry, Queen' s University, 90 Bader Lane, Kingston, Ontario, K7L 3N6 (Canada); Aldea, Gabriela [Department of Chemistry, Queen' s University, 90 Bader Lane, Kingston, Ontario, K7L 3N6 (Canada); Petru Poni Institute of Macromolecular Chemistry Iasi, Aleea Grigore Ghica Voda 41A, 700487 Iasi (Romania); Nunzi, Jean-Michel, E-mail: nunzijm@queensu.c [Department of Chemistry, Queen' s University, 90 Bader Lane, Kingston, Ontario, K7L 3N6 (Canada)

    2010-01-15

    The plasmon enhanced luminescence of a rare-earth complex Tris(6, 6, 7, 7, 8, 8, 8-heptafluoro-2, 2-dimethyl-3, 5-octanedionato) europium (Eu(fod){sub 3}) was investigated. A polyvinyl alcohol (PVA) thin film was successfully adopted as a spacer to separate the Eu complex from the silver island film (SIF), and five-fold enhancement of the radiative decay rate of the Eu complex on SIF was demonstrated based on the luminescence intensity and lifetime measurement. Investigation of the distance dependent luminescence indicates that 7 nm is an optimal distance for SIF enhanced Eu luminescence. Plasmon enhanced rare-earth luminescence based on an organic film spacer would find potential applications in plasmon enhanced organic light emitting diode (OLED) devices.

  7. Novel fluorescent probe for low density lipoprotein, based on the enhancement of Europium emission band

    OpenAIRE

    Courrol, Lilia Coronato; Monteiro, A.M.; SILVA, F.R.O.; L. Gomes; VIEIRA, N.D.; Gidlund, Magnus; Figueiredo Neto, A.M.

    2007-01-01

    We report here the observation of the enhancement of Europium-tetracycline complex emission in Low Density Lipoprotein (LDL) solutions. Europium emission band of tetracycline solution containing Europium (III) chloride hexahydrate was tested to obtain effective enhancement in the presence of native LDL and oxidized LDL. Europium emission lifetime in the presence of lipoproteins was measured, resulting in a simple method to measure the lipoproteins quantity in an aqueous solution at physiologi...

  8. 33 CFR 156.310 - Prohibited areas.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Prohibited areas. 156.310 Section... the Gulf of Mexico § 156.310 Prohibited areas. Lightering operations are prohibited within the following areas in the Gulf of Mexico: (a) Claypile—prohibited area. This prohibited area consists of the...

  9. 32 CFR 156.3 - Policy.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Policy. 156.3 Section 156.3 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE SECURITY DEPARTMENT OF DEFENSE PERSONNEL SECURITY... employee of the Department of Defense, accepted for entrance into the Armed Forces of the United States...

  10. 40 CFR 97.156 - Account error.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Account error. 97.156 Section 97.156... Account error. The Administrator may, at his or her sole discretion and on his or her own motion, correct any error in any CAIR NOX Allowance Tracking System account. Within 10 business days of making such...

  11. Europium ion as a probe for binding sites to carrageenans

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Ana P.; Goncalves, Rogeria R.; Serra, Osvaldo A. [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo 14040-901 (Brazil); Zaniquelli, Maria Elisabete D. [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo 14040-901 (Brazil)], E-mail: medzaniquelli@ffclrp.usp.br; Wong, Kenneth [Laboratorio de Fisico-Quimica, Centro de Pesquisas de Paulinia, Rhodia Brasil, Paulinia, Sao Paulo (Brazil)

    2007-12-15

    Carrageenans, sulfated polysaccharides extracted from red algae, present a coil-helix transition and helix aggregation dependence on the type and concentration of counterions. In this study, we focus attention on a mixed valence counterion system: Eu{sup 3+}/Na{sup +} or K{sup +} with different gel-forming carrageenans: kappa, iota, and kappa-2. Results of stationary and time-dependent luminescence showed to be a suitable tool to probe ion binding to both the negatively charged sulfate group and the hydroxyl groups present in the biopolymer. For lower europium ion concentrations, a single longer decay emission lifetime was detected, which was attributed to the binding of europium ion to the carrageenan sulfate groups. An additional decay ascribed to europium binding to hydroxyl groups was observed above a threshold concentration, and this decay was dependent on the carrageenan charge density. Symmetry of the europium ion microenvironment was estimated by the ratio between the intensities of its emission bands, which has been shown to depend on the concentration of europium ions and on the specificity of the monovalent counterion bound to the carrageenan.

  12. First-Principles Investigations on Europium Monoxide

    KAUST Repository

    Wang, Hao

    2011-05-01

    Europium monoxide is both an insulator and a Heisenberg ferromagnet (Tc=69 K). In the present thesis, the author has investigated the electronic structure of different types of EuO by density functional theory. The on-site Coulomb interaction of the localized Eu 4f and 5d electrons, which is wrongly treated in the standard generalized gradient approximation method, is found to be crucial to obtain the correct insulating ground state as observed in experiments. Our results show that the ferromagnetism is stable under pressure, both hydrostatic and uniaxial. For both types of pressure an insulator-metal transition is demonstrated. Moreover, the experimentally observed insulator-metal transition in oxygen deficient and gadolinium-doped EuO is reproduced in our calculations for impurity concentrations of 6.25% and 25%. Furthermore, a 10- layer EuO thin film is theoretically predicted to be an insulator with a narrow band gap of around 0.08 eV, while the Si/EuO interface shows metallic properties with the Si and O 2p as well as Eu 5d bands crossing the Fermi level.

  13. Chloride, bromide and iodide scintillators with europium

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2016-09-27

    A halide scintillator material is disclosed where the halide may comprise chloride, bromide or iodide. The material is single-crystalline and has a composition of the general formula ABX.sub.3 where A is an alkali, B is an alkali earth and X is a halide which general composition was investigated. In particular, crystals of the formula ACa.sub.1-yEu.sub.yI.sub.3 where A=K, Rb and Cs were formed as well as crystals of the formula CsA.sub.1-yEu.sub.yX.sub.3 (where A=Ca, Sr, Ba, or a combination thereof and X=Cl, Br or I or a combination thereof) with divalent Europium doping where 0.ltoreq.y.ltoreq.1, and more particularly Eu doping has been studied at one to ten mol %. The disclosed scintillator materials are suitable for making scintillation detectors used in applications such as medical imaging and homeland security.

  14. Electrochemical extraction of europium from molten fluoride media

    Energy Technology Data Exchange (ETDEWEB)

    Gibilaro, M. [Universite de Toulouse, INPT, UPS, Laboratoire de Genie Chimique, Departement Procedes Electrochimiques, F-31062 Toulouse cedex 09 (France); CNRS, Laboratoire de Genie Chimique, F-31062 Toulouse cedex 09 (France); Massot, L., E-mail: massot@chimie.ups-tlse.f [Universite de Toulouse, INPT, UPS, Laboratoire de Genie Chimique, Departement Procedes Electrochimiques, F-31062 Toulouse cedex 09 (France); CNRS, Laboratoire de Genie Chimique, F-31062 Toulouse cedex 09 (France); Chamelot, P.; Cassayre, L.; Taxil, P. [Universite de Toulouse, INPT, UPS, Laboratoire de Genie Chimique, Departement Procedes Electrochimiques, F-31062 Toulouse cedex 09 (France); CNRS, Laboratoire de Genie Chimique, F-31062 Toulouse cedex 09 (France)

    2009-12-15

    This work concerns the extraction of europium from molten fluoride media. Two electrochemical ways have been examined: (i) the use of a reactive cathode made of copper and (ii) the co-deposition with aluminium on inert electrode, leading to the formation of europium-copper and europium-aluminium alloys, respectively, as identified by SEM-EDS analysis. Cyclic voltammetry and square wave voltammetry were used to identify the reduction pathway and to characterise the step of Cu-Eu and Al-Eu alloys formation. Then, electrochemical extractions using the two methodologies have been performed with extraction efficiency around 92% for copper electrode and 99.7% for co-reduction with aluminium ions.

  15. Solubilization of europium fulvate in aqueous solutions containing complexing agents

    Energy Technology Data Exchange (ETDEWEB)

    Legin, E.K.; Trifonov, Yu.I.; Khokhlov, M.L. [Khlopin Radium Inst., St. Petersburg (Russian Federation)] [and others

    1995-07-01

    The europium fulvate complex is synthesized and characterized by spectroscopic and chemical methods. By an example of this complex, it is demonstrated that metal complexes of humic substances are solubilized in the presence of complexing anions such as OAc{sup {minus}}, C{sub 2}O{sup 2{minus}}{sub 4}, and EDTA{sup 2{minus}}. The solubilization is studied by the optical and radioactive tracer methods. The solubilization of europium fulvate increases parallel to the complexing power of anions. In the solid fulvate europium is bonded stronger than in the ethylenediaminetetraacetate complex. The solubilization is considered as a potential source for decomposition of the {open_quotes}absorbing soil complex,{close_quotes} resulting in mobile forms of a metal and humic component in soils and soil waters.

  16. Excess europium content in Precambrian sedimentary rocks and continental evolution

    Science.gov (United States)

    Jakes, P.; Taylor, S. R.

    1974-01-01

    It is proposed that the europium excess in Precambrian sedimentary rocks, relative to those of younger age, is derived from volcanic rocks of ancient island arcs, which were the source materials for the sediments. Precambrian sedimentary rocks and present-day volcanic rocks of island arcs have similar REE patterns, total REE abundances, and excess Eu, relative to the North American shale composite. The present upper crustal REE pattern, as exemplified by that of sediments, is depleted in Eu, relative to chondrites. This depletion is considered to be a consequence of development of a granodioritic upper crust by partial melting in the lower crust, which selectively retains europium.

  17. 10 CFR Appendix C to Part 20 - Quantities 1 of Licensed Material Requiring Labeling

    Science.gov (United States)

    2010-01-01

    ... Samarium-151 10 Samarium-153 100 Samarium-155 1,000 Samarium-156 1,000 Europium-145 100 Europium-146 100 Europium-147 100 Europium-148 10 Europium-149 100 Europium-150 (12.62h) 100 Europium-150 (34.2y) 1 Europium-152m 100 Europium-152 1 Europium-154 1 Europium-155 10 Europium-156 100 Europium-157 100 Europium-158 1...

  18. Murine High Specificity/Sensitivity Competitive Europium Insulin Autoantibody Assay

    Science.gov (United States)

    Babaya, Naru; Liu, Edwin; Miao, DongMei; Li, Marcella; Yu, Liping

    2009-01-01

    Abstract Background Most insulin autoantibody assays for both human and animal models are in a radioassay format utilizing 125I-insulin, but despite the radioassay format international workshops have documented difficulty in standardization between laboratories. There is thus a need for simpler assay formats that do not utilize radioactivity, yet retain the high specificity and sensitivity of radioassays. Methods To establish an easier enzyme-linked immunosorbent assay (ELISA) for insulin autoantibodies of non-obese diabetic (NOD) mice, we used an ELISA format, competition with unlabeled insulin, europium-avidin, and time-resolved fluorescence detection (competitive europium insulin autoantibody assay). Results The competitive europium assay of insulin autoantibodies when applied to sera from NOD mice had high sensitivity and specificity (92% sensitivity, 100% specificity) compared to our standard insulin autoantibody radioassay (72% sensitivity, 100% specificity) in analyzing blind workshop sera. It is noteworthy that though the assay has extremely high sensitivity for murine insulin autoantibodies and utilizes human insulin as target autoantigen, human sera with high levels of insulin autoantibodies are not detected. Conclusions Our results clearly indicate that low levels of insulin autoantibodies can be detected in an ELISA-like format. Combining a europium-based ELISA with competition with fluid-phase autoantigen can be applicable to many autoantigens to achieve high specificity and sensitivity in an ELISA format. PMID:19344197

  19. Tridentate benzimidazole-pyridine-tetrazolates as sensitizers of europium luminescence.

    Science.gov (United States)

    Shavaleev, Nail M; Eliseeva, Svetlana V; Scopelliti, Rosario; Bünzli, Jean-Claude G

    2014-05-19

    We report on new anionic tridentate benzimidazole-pyridine-tetrazolate ligands that form neutral 3:1 complexes with trivalent lanthanides. The ligands are UV-absorbing chromophores that sensitize the red luminescence of europium with energy-transfer efficiency of 74-100%. The lifetime and quantum yield of the sensitized europium luminescence increase from 0.5 ms and 12-13% for the as-prepared solids to 2.8 ms and 41% for dichloromethane solution. From analysis of the data, the as-prepared solids can be described as aqua-complexes [Ln(κ(3)-ligand)2(κ(1)-ligand)(H2O)x] where the coordinated water molecules are responsible for the strong quenching of the europium luminescence. In solution, the coordinated water molecules are replaced by the nitrogen atoms of the κ(1)-ligand to give anhydrous complexes [Ln(κ(3)-ligand)3] that exhibit efficient europium luminescence. X-ray structures of the anhydrous complexes confirm that the lanthanide ion (La(III), Eu(III)) is nine-coordinate in a distorted tricapped trigonal prismatic environment and that coordination of the lanthanide ion by tetrazolate is weaker than by carboxylate.

  20. Europium 2-benzofuranoate: Synthesis and use for bioimaging

    Science.gov (United States)

    Utochnikova, V. V.; Koshelev, D. S.; Medvedko, A. V.; Kalyakina, A. S.; Bushmarinov, I. S.; Grishko, A. Yu; Schepers, U.; Bräse, S.; Vatsadze, S. Z.

    2017-12-01

    Europium 2-benzofuranoate Eu(BFC)3(H2O)3 was successfully used for bioimaging in cellulo due to the combination of high solubility and high luminescence intensity in solution. It was possible due to the purposeful variation of the aromatic core of carboxylate anion.

  1. SEPARATION OF EUROPIUM FROM OTHER LANTHANIDE RAE EARTHS BY SOLVENT EXTRACTION

    Science.gov (United States)

    Peppard, D.F.; Horwitz, E.P.; Mason, G.W.

    1963-02-12

    This patent deals with a process of separating europium from other lanthanides present in aqueous hydrochloric or sulfuric acid solutions. The europium is selectively reduced to the divalent state with a divalent chromium salt formed in situ from chromium(III) salt plus zinc amalgam. The other trivalent lanthanides are then extracted away from the divalent europium with a nitrogen-flushed phosphoric acid ester or a phosphonic acid ester. (AEC)

  2. Distribution, elimination, and renal effects of single oral doses of europium in rats.

    Science.gov (United States)

    Ohnishi, Keiko; Usuda, Kan; Nakayama, Shin; Sugiura, Yumiko; Kitamura, Yasuhiro; Kurita, Akihiro; Tsuda, Yuko; Kimura, Motoshi; Kono, Koichi

    2011-11-01

    Single doses of europium (III) chloride hexahydrate were orally administered to several groups of rats. Cumulative urine samples were taken at 0-24 h, and blood samples were drawn after 24-h administration. The europium concentration was determined in these samples by inductively coupled plasma atomic emission spectroscopy. The volume, creatinine, ß-2-microglobulin, and N-acetyl-ß-D-glucosaminidase were measured in the urine samples to evaluate possible europium-induced renal effects. The blood samples showed low europium distribution, with an average of 77.5 μg/L for all groups. Although the urinary concentration and excretion showed dose-dependent increases, the percentage of europium excreted showed a dose-dependent decrease, with an average of 0.31% in all groups. The administration of europium resulted in a significant decrease of creatinine and a significant increase of urinary volume, N-acetyl-ß-D-glucosaminidase, and ß-2-microglobulin. Rare earth elements, including europium, are believed to form colloidal conjugates that deposit in the reticuloendothelial system and glomeruli. This specific reaction may contribute to low europium bioavailability and renal function disturbances. Despite low bioavailability, the high performance of the analytical method for determination of europium makes the blood and urine sampling suitable tools for monitoring of exposure to this element. The results presented in this study will be of great importance in future studies on the health impacts of rare earth elements.

  3. 29 CFR 1910.156 - Fire brigades.

    Science.gov (United States)

    2010-07-01

    ... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Fire Protection § 1910.156 Fire brigades. (a) Scope and application—(1... equipment of fire brigades whenever they are established by an employer. (2) Application. The requirements... seconds at 4 psi (28 kPa) pressure. (ii) Exterior materials of gloves shall be flame resistant and shall...

  4. [Synthesis and luminescence properties of reactive ternary europium complexes].

    Science.gov (United States)

    Guo, Dong-cai; Shu, Wan-gen; Zhang, Wei; Liu, You-nian; Zhou, Yue

    2004-09-01

    In this paper, five new reactive ternary europium complexes were synthesized with the first ligand of 1,10-phenanthroline and the reactive second ligands of maleic anhydride, acrylonitrile, undecenoic acid, oleic acid and linoleic acid, and also characterized by means of elemental analysis, EDTA titrimetric method, FTIR spectra and UV spectra. The fluorescence spectra show that the five new ternary complexes have much higher luminescence intensity than their corresponding binary complexes, and the synergy ability sequence of the five reactive ligands is as follows: linoleic acid > oleic acid > acrylonitrile > maleic anhydride > undecenoic acid. At the same time, the reactive ternary europium complexes coordinated with the reactive ligands, which can be copolymerized with other monomers, will provide a new way for the synthesis of bonding-type rare earth polymer functional materials with excellent luminescence properties.

  5. Dicty_cDB: AFA156 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available AF (Link to library) AFA156 (Link to dictyBase) - - - Contig-U10843-1 AFA156F (Link... to Original site) AFA156F 604 - - - - - - Show AFA156 Library AF (Link to library) Clone ID AFA156 (Link to dict...yBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Contig-U10843-1 Original site URL http://dict...EVAIMSKIFHPNIVLFLGACTSTPGKLMICTELMKGNLESLLLDPMVKLP LITRMRMAKDAALGVLWLHS--- Transl...yhtht**KTMATQQQQQQQQQQQQQIK ARKDIQIQQAQSASDILGPPEISETEITTESILGDGSFGTVYKGRCRLKDVAVKVMLKQV DQKTLTDFRKEVAIMSKIFHPNIVLFLGACTSTPGKLMICT

  6. Solvent extraction of europium(III) to a fluorine-free ionic liquid phase with a diglycolamic acid extractant

    OpenAIRE

    Rout, Alok; Souza, Ernesto Rezende; Binnemans, Koen

    2014-01-01

    Europium(III) was extracted by bis(2-ethylhexyl)diglycolamic acid (DEHDGA) dissolved in the non-fluorinated ionic liquid tetraoctylammonium dodecyl sulphate, [N8888][DS]. The extraction behaviour of europium(III) was investigated as a function of various parameters: pH, extractant concentration, concentration of the europium(III) ion in the aqueous feed and concentration of the salting-out agent. A comparison was made with extraction of europium(III) by the acidic extractants bis(2-ethylhexyl...

  7. Silver lead borate glasses doped with europium ions for phosphors ...

    Indian Academy of Sciences (India)

    2017-07-25

    Jul 25, 2017 ... Abstract. Europium (Eu3+) doped silver lead borate glasses with the composition of xEu2O3−(1 − x)Ag2. O−29PbO−70B2O3 (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol%) have been successfully prepared by conventional melt quenching method. Thermal, structural and luminescence properties have been studied ...

  8. Silver lead borate glasses doped with europium ions for phosphors ...

    Indian Academy of Sciences (India)

    Europium (Eu 3 + ) doped silver lead borate glasses with the composition of x Eu 2 O 3 −( 1 − x )Ag 2 O−29PbO−70B 2 O 3 ( x = 0 , 0.1, 0.2, 0.3, 0.4 and 0.5 mol%) have been successfully prepared by conventional meltquenching method. Thermal, structural and luminescence properties have been studied using ...

  9. Synthesis and luminescence properties for europium oxide nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Mo Zunli, E-mail: mozl@163.com [Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China) and State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi' an 710072 (China); Deng Zhepeng; Guo Ruibin [Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China); Fu Qiangang [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi' an 710072 (China); Feng Chao; Liu Pengwei; Sun Yu [Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China)

    2012-01-25

    Highlights: Black-Right-Pointing-Pointer A novel high temperature sensitive fluorescent CNTs/Eu{sub 2}O{sub 3} nanocomposite was fabricated. Black-Right-Pointing-Pointer The nanocomposite showed strong fluorescent emission peaks at around 540 and 580 nm after calcined beyond 620 Degree-Sign C for 4 h. Black-Right-Pointing-Pointer The ultrahigh fluorescence intensity of the nanocomposites resulted from a synergetic effect of CNTs and europium oxide. Black-Right-Pointing-Pointer We also discovered that CNTs had an effect of fluorescence quenching. - Abstract: A novel high temperature sensitive fluorescent nanocomposite has been successfully synthesized by an economic hydrothermal method using carbon nanotubes (CNTs), europium oxide, and sodium dodecyl benzene sulfonate (SDBS). To our great interest, the nanocomposites show high temperature sensitivity after calcinations at various temperatures, suggesting a synergetic effect of CNTs and europium oxide which leads to ultrahigh fluorescence intensity of europium oxide nanotubes. When the novel high temperature sensitive fluorescent nanocomposites were calcined beyond 620 Degree-Sign C for 4 h, the obtained nanocomposites have a strong emission peak at around 540 and 580 nm, due to the {sup 5}D{sub 0} {yields} {sup 7}F{sub j} (j = 0, 1) forced electric dipole transition of Eu{sup 3+} ions. In turn, the emission spectra showed a slight blue shift. The intensity of this photoluminescence (PL) band is remarkably temperature-dependent and promotes strongly beyond 620 Degree-Sign C. This novel feature is attributed to the thermally activated carrier transfer process from nanocrystals and charged intrinsic defects states to Eu{sup 3+} energy levels. The novel high temperature sensitive fluorescent nanocomposite has potential applications in high temperature warning materials, sensors and field emission displays. It is also interesting to discover that CNTs have the effect of fluorescence quenching.

  10. Optical and magnetization studies on europium based iron pnictides

    Energy Technology Data Exchange (ETDEWEB)

    Zapf, Sina Maria Ute

    2015-07-01

    The investigations carried out in the framework of this thesis mainly concentrate on europium based iron pnictides. These are a peculiar member of the 122 family as they develop at low temperatures (∝20K) an additional magnetic order of the local rare earth moments. Therefore, europium based iron pnictides provide a unique platform to study the interplay of structural, magnetic and electronic effects in high-temperature superconductors. For this challenging purpose, we have employed SQUID magnetometry and Fourier-transform infrared spectroscopy on EuFe{sub 2}(As{sub 1-x}P{sub x}){sub 2} single crystals. By systematic studies of the in- and out-of-plane magnetic properties of a series of single crystals, we derived the complex magnetic phase diagram of europium based iron pnictides, which contains an A-type antiferromagnetic and a re-entrant spin glass phase. Furthermore, we have investigated the magneto-optical properties of EuFe{sub 2}As{sub 2}, revealing a much more complex magnetic detwinning process than expected. These studies demonstrate a remarkable interdependence between magnetic, electronic and structural effects that might be very important to understand the unconventional superconductivity in these fascinating materials.

  11. Use of europium ions for SAD phasing of lysozyme at the Cu Kα wavelength

    OpenAIRE

    Vijayakumar, Balakrishnan; Velmurugan, Devadasan

    2012-01-01

    Europium(III) ions bound to the surface of hen egg-white lysozyme were found to exhibit good anomalous signal facilitating SAD phasing using laboratory-source data and automated model building. The europium ion-binding sites were observed up to the 15σ level.

  12. Enhancement in red emission at room temperature from europium doped ZnO nanowires by 1,10 phenanthroline-europium interface induced resonant excitations

    Directory of Open Access Journals (Sweden)

    Soumen Dhara

    2017-02-01

    Full Text Available We show that europium doped ZnO nanowires after surface modification with organic ligand, 1,10 phenanthroline (phen leads to strong red emission at 613 nm which is a characteristic emission from the atomic levels of Eu3+. Surface modification with phen leads to formation of phenanthroline-europium interface on the surface of the nanowires due to attachment of Eu3+ ions. After an optimized surface modification with phen, intensity of both the UV emission (band edge and red emission improved by two orders of magnitude at room temperature. We observed multiple energy transfer pathways to the energy levels of Eu3+ ions through the phenanthroline-europium interface, which found to be very effective to the significant enhancement of emission from the dopant Eu3+. This study shows a new insight in to the energy transfer process from phen to the europium doped ZnO system.

  13. 42 CFR 483.156 - Registry of nurse aides.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 5 2010-10-01 2010-10-01 false Registry of nurse aides. 483.156 Section 483.156... That Must Be Met by States and State Agencies: Nurse Aide Training and Competency Evaluation, and Paid Feeding Assistants § 483.156 Registry of nurse aides. (a) Establishment of registry. The State must...

  14. 7 CFR 4279.156 - Planning and performing development.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Planning and performing development. 4279.156 Section 4279.156 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS... Industry Loans § 4279.156 Planning and performing development. (a) Design policy. The lender must ensure...

  15. 18 CFR 156.1 - Who may apply.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Who may apply. 156.1 Section 156.1 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT... GAS ACT § 156.1 Who may apply. Any person or municipality as defined in section 2 of the Natural Gas...

  16. 33 CFR 156.115 - Person in charge: Limitations.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Person in charge: Limitations. 156.115 Section 156.115 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Operations § 156.115 Person in charge: Limitations. (a) No person may serve as the person in charge of...

  17. Dual doped graphene oxide for electrochemical sensing of europium ion

    Science.gov (United States)

    Kumar, Sunil; Patra, Santanu; Madhuri, Rashmi; Sharma, Prashant K.

    2017-05-01

    This present work represents a single step hydrothermal method for the preparation of N, and N, S dual doped graphene oxide (GO). First time, a comparative electrochemical study between single dope and dual doped GO was carried out using potassium ferrocyanide as an electro-active probe molecule and found that the dual doped GO has the highest electrocatalytic activity than single doped, due to the presence of two heteroatoms as a doping material. Afterwards, the dual doped GO was successfully applied for the electrochemical detection of a rare earth element i.e. europium, with LOD value of 5.92 μg L-1.

  18. Crystal growth of nanoscaled europium selenide having characteristic crystal shapes

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Atsushi; Adachi, Taka-aki [Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan); Hasegawa, Yasuchika, E-mail: hasegawa@ms.naist.j [Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan); Kawai, Tsuyoshi [Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan)

    2009-12-04

    Tetrapod-shaped EuSe nanocrystals were prepared through the thermal reduction of europium chloride an organic selenide complex, n-hexadecylamine, and two additives oleic acid and oleylamine. The obtained EuSe nanoparticles were characterized by X-ray diffraction (XRD). The crystal grain size from the XRD spectrum was estimated to be 50 nm. In contrast, observation of the transmission electron microscope (TEM) gave larger sized EuSe (average size: 200 nm). Anisotropic crystal-growth of EuSe nanocrystals was achieved by addition of a small amount of oleic acid in the crystal growth process.

  19. Photoprotective properties of the fluorescent europium complex in UV-irradiated skin.

    Science.gov (United States)

    Vogt, O; Lademann, J; Rancan, F; Meinke, M C; Schanzer, S; Stockfleth, E; Sterry, W; Lange-Asschenfeldt, B

    2013-01-01

    In this study, we compared the UV-protective abilities of the europium complex compared to titanium dioxide, which represents the most common physical filter for ultraviolet light in the broad-band spectral range. The UV absorption and light transformative capacities of the europium complex were evaluated using a spectrometer with a double-integrating sphere showing that the europium complex does not only absorb and reflect UV light, but transforms it into red and infrared light. It was found that the europium complex binds to the surface of Jurkat cells in vitro. Cells incubated with the europium complex showed a significantly higher viability after UVA and UVB irradiation as compared to untreated cells and cells incubated with titanium dioxide pointing out its photoprotective properties. The europium complex and titanium dioxide show similar penetration capacities into the stratum corneum as tested in human and porcine skin using tape stripping analysis. The europium complex has proved to be an efficient UV filter with a low cyto- and phototoxic profile and therefore represents a potential candidate for use in sunscreen formulations. Copyright © 2013 S. Karger AG, Basel.

  20. Arabidopsis mutant sk156 reveals complex regulation of SPL15 in a miR156-controlled gene network

    Directory of Open Access Journals (Sweden)

    Wei Shu

    2012-09-01

    Full Text Available Abstract Background The Arabidopsis microRNA156 (miR156 regulates 11 members of the SQUAMOSA PROMOTER BINDING PROTEIN LIKE (SPL family by base pairing to complementary target mRNAs. Each SPL gene further regulates a set of other genes; thus, miR156 controls numerous genes through a complex gene regulation network. Increased axillary branching occurs in transgenic Arabidopsis overexpressing miR156b, similar to that observed in loss-of-function max3 and max4 mutants with lesions in carotenoid cleavage dioxygenases. Arabidopsis miR156b was found to enhance carotenoid levels and reproductive shoot branching when expressed in Brassica napus, suggesting a link between miR156b expression and carotenoid metabolism. However, details of the miR156 regulatory network of SPL genes related to carotenoid metabolism are not known. Results In this study, an Arabidopsis T-DNA enhancer mutant, sk156, was identified due to its altered branching and trichome morphology and increased seed carotenoid levels compared to wild type (WT ecovar Columbia. Enhanced miR156b expression due to the 35S enhancers present on the T-DNA insert was responsible for these phenotypes. Constitutive and leaf primodium-specific expression of a miR156-insensitive (mutated SPL15 (SPL15m largely restored WT seed carotenoid levels and plant morphology when expressed in sk156. The Arabidopsis native miR156-sensitive SPL15 (SPL15n and SPL15m driven by a native SPL15 promoter did not restore the WT phenotype in sk156. Our findings suggest that SPL15 function is somewhat redundant with other SPL family members, which collectively affect plant phenotypes. Moreover, substantially decreased miR156b transcript levels in sk156 expressing SPL15m, together with the presence of multiple repeats of SPL-binding GTAC core sequence close to the miR156b transcription start site, suggested feedback regulation of miR156b expression by SPL15. This was supported by the demonstration of specific in vitro

  1. Low-voltage cathodoluminescence of europium-activated yttrium orthovanadate

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, M.L.F.

    1995-03-01

    Emissive flat panel display systems operating in full color demand higher performance at low voltages (ca. 501000 V) from cathodoluminescent (CL) phosphors than cathode ray tubes require. Hydrothermal synthesis has been suggested as a route to phosphors with improved efficiencies, lower voltage thresholds, and increased saturation power. This hypothesis was tested in europium-doped yttrium orthovanadate (YVO{sub 4}:Eu), an efficient, red emitting CL phosphor. The CL efficiency of YVO{sub 4}:Eu crystallized from aqueous solution at 200{degrees}C is relatively low until it is annealed. The distribution of particle sizes in the low-temperature phosphor is similar to that in material made via a solid-state route, but crystallites remain much smaller (ca. 400 {Angstrom}) until they are annealed. These observations, along with the anomalously strong dependence of CL intensity on europium concentration, support a model in which efficiency principally depends on crystallite size. CL efficiency of both solid state and hydrothermal YVO{sub 4}:Eu increases with voltage at constant power. Surface-bound electrons are likely the dominant influence on efficiency at voltages near threshold. Saturation power is independent of synthetic route. It is apparent that the CL properties of hydrothermally synthesized YVO{sub 4}:Eu are essentially the same as those of YVO{sub 4}:Eu produced via conventional, high-temperature routes.

  2. In Vivo Toxicity Studies of Europium Hydroxide Nanorods in Mice

    Science.gov (United States)

    Patra, Chitta Ranjan; Abdel Moneim, Soha S.; Wang, Enfeng; Dutta, Shamit; Patra, Sujata; Eshed, Michal; Mukherjee, Priyabrata; Gedanken, Aharon; Shah, Vijay H; Mukhopadhyay, Debabrata

    2009-01-01

    Lanthanide nanoparticles and nanorods have been widely used for diagnostic and therapeutic applications in biomedical nanotechnology due to their fluorescence properties and pro-angiogenic to endothelial cells, respectively. Recently, we have demonstrated that europium (III) hydroxide [EuIII(OH)3] nanorods, synthesized by the microwave technique and characterized by several physico-chemical techniques, can be used as pro-angiogenic agents which introduce future therapeutic treatment strategies for severe ischemic heart/limb disease, and peripheral ischemic disease. The toxicity of these inorganic nanorods to endothelial cells was supported by several in vitro assays. To determine the in vivo toxicity, these nanorods were administered to mice through intraperitoneal injection (IP) everyday over a period of seven days in a dose dependent (1.25 to 125 mgKg−1day−1) and time dependent manner (8–60 days). Bio-distribution of europium elements in different organs was analyzed by inductively coupled plasma mass spectrometry (ICPMS). Short-term (S-T) and long-term (L-T) toxicity studies (mice sacrificed on day 8 and 60 for S-T and L-T, respectively) show normal blood hematology and serum clinical chemistry with the exception of a slight elevation of liver enzymes. Histological examination of nanorod treated vital organs (liver, kidney, spleen and lungs) showed no or only mild histological changes that indicate mild toxicity at the higher dose of nanorods. PMID:19616569

  3. Temperature dependences in electron-stimulated desorption of neutral europium

    CERN Document Server

    Ageev, V N; Madey, T E

    2003-01-01

    The electron-stimulated desorption (ESD) yield for neutral europium (Eu) atoms from Eu layers adsorbed on oxygen-covered tungsten surfaces has been measured as a function of electron energy, europium coverage and degree of oxidation of tungsten, with an emphasis on effects of substrate temperature. The measurements have been carried out using a time-of-flight method and surface ionization detector. We expand on an earlier report, and compare ESD of multivalent Eu with ESD of monovalent alkali atoms, studied previously. The Eu atom ESD is a complicated function of Eu coverage, electron energy and substrate temperature. In the coverage range 0.05-0.35 monolayer (ML), overlapping resonant-like Eu atom yield peaks are observed at electron energies E sub e of 36 and 41 eV that might be associated with Eu or W shallow core level excitations. Additional resonant-like peaks are seen at E sub e of 54 and 84 eV that are associated with W 5p and 5s level excitations. The Eu atom yield peaks at 36 and 41 eV are seen only...

  4. The Oxidation State of Europium in Halide Glasses

    Science.gov (United States)

    Weber, J.K.R.; Vu, M.; Paßlick, C.; Schweizer, S.; Brown, D.E.; Johnson, C.E.; Johnson, J.A.

    2012-01-01

    The luminescent properties of divalent europium ions can be exploited to produce storage phosphors for x-ray imaging applications. The relatively high cost and limited availability of divalent europium halides makes it desirable to synthesize them from the readily available trivalent salts. In this work, samples of pure EuCl3 and fluoride glass melts doped with EuCl3 were processed at 700-800 °C in an inert atmosphere furnace. The Eu oxidation state in the resulting materials was determined using fluorescence and Mössbauer spectroscopy. Heat treatment of pure EuCl3 for 10 minutes at 710 °C resulted in a material comprising approximately equal amounts of Eu2+ and Eu3+. Glasses made using mixtures of EuCl2 and EuCl3 in the starting material contained both oxidation states. This paper describes the sample preparation and analysis and discusses the results in the context of chemical equilibria in the melts. PMID:22101252

  5. Innovative triboluminescence study of multivitamin doped europium tetrakis

    Energy Technology Data Exchange (ETDEWEB)

    Fontenot, R.S. [Alabama A and M University, Department of Physics, Chemistry, and Mathematics, P.O. Box 1268, Normal, Alabama 35762 (United States); University of Louisiana at Lafayette, Department of Physics, P.O. Box 44210, Lafayette, LA 70504 (United States); Bhat, K.N.; Aggarwal, M.D. [Alabama A and M University, Department of Physics, Chemistry, and Mathematics, P.O. Box 1268, Normal, Alabama 35762 (United States); Hollerman, W.A. [University of Louisiana at Lafayette, Department of Physics, P.O. Box 44210, Lafayette, LA 70504 (United States)

    2012-05-15

    As the Space Shuttle program ends, NASA is developing the next generation of space vehicles. These new concept designs will require new and innovative structural health monitoring capabilities. One way to solve this problem is with smart impact sensors that use triboluminescent materials. In 2011, the authors reported an 82% increase in the triboluminescence yield of europium dibenzoylmethide triethylammonium (EuD{sub 4}TEA) by changing the starting material. It has been shown that introduction of dopants tends to enhance the triboluminescent light yield. Here we report the successful synthesis of a multivitamin doped europium tetrakis which appears to be spherical in shape. Inductively Coupled Plasma - Optical Emission Spectroscopy analysis showed the presence of 3.6% calcium, 0.62% magnesium, 0.1% iron, 0.01% copper and manganese. This new product has no shift in the triboluminescent or photoluminescent emission peaks, but only a change in the intensity. In addition, the doped EuD{sub 4}TEA powder statistically emits more triboluminescence while having the same decay time. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Photoactive thin films of polycaprolactam doped with europium (III) complex using phenylalanine as ligand

    Energy Technology Data Exchange (ETDEWEB)

    Santos Garcia, Irene Teresinha, E-mail: irene@iq.ufrgs.br [Departamento de Fisico-Quimica, Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, Bairro Agronomia, CEP 91501-970, Porto Alegre, RS (Brazil); Velleda Ribeiro, Patricia; Silva Correa, Diogo; Neto da Cunha, Igor Michel; Lenin Villarreal Carreno, Neftali [Instituto de Quimica e Geociencias, Universidade Federal de Pelotas, Campus Capao do Leao, s/n. CEP 96010-900, Pelotas, RS (Brazil); Ceretta Moreira, Eduardo [PPGEE, Universidade Federal do Pampa, Campus Bage, Bage- RS (Brazil); Severo Rodembusch, Fabiano [Departamento de Quimica Organica, Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, Bairro Agronomia, CEP 91501-970, Porto Alegre, RS (Brazil)

    2011-12-01

    A photoactive complex based on europium(III) using the amino acid phenylalanine as ligand was prepared and characterized. The obtained europium(III)/phenylalanine complex presents an effective energy transfer from ligands to the rare earth center. The observed photoluminescent behavior for europium(III)/phenylalanine complex was similar to the well known europium(III)/ acetyl-{beta}-acetonate hydrate. New photoactive polyamide thin films were prepared using polycaprolactam as host of these complexes. The structural characterizations of the films were studied through Rutherford backscattering (RBS), Fourier transform infrared (FTIR) and Raman spectroscopies. The polyamide films doped with the amino acid and acetyl-{beta}-acetonate rare earth complexes maintain the original photoluminescent behavior, narrow emission bands corresponding to transitions {sup 5}D{sub 0} {yields} {sup 7}F{sub 0-4}, which indicates that this polymer is an excellent host to these complexes.

  7. Synthesis and luminescence properties of salicylaldehyde isonicotinoyl hydrazone derivatives and their europium complexes.

    Science.gov (United States)

    Shan, Wenfei; Liu, Fen; Liu, Jiang; Chen, Yanwen; Yang, Zehui; Guo, Dongcai

    2015-09-01

    Four novel salicylaldehyde isonicotinoyl hydrazone derivatives and their corresponding europium ion complexes were synthesized and characterized, while the luminescence properties and the fluorescence quantum yields of the target complexes were investigated. The results indicated that the ligands favored energy transfers to the emitting energy level of europium ion, and four target europium complexes showed the characteristic luminescence of central europium ion. Besides the luminescence intensity of the complex with methoxy group, which possessed the highest fluorescence quantum yield (0.522), was stronger than that of other complexes. Furthermore, the electrochemical properties of the target complexes were further investigated by cyclic voltammetry, the results indicated that the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) energy levels and the oxidation potential of the complexes with electron donating group increased, however, that of the complexes with accepting electron group decreased. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. [Synthesis and luminescence properties of ternary complexes of europium with aromatic carboxylic acid and acrylonitrile].

    Science.gov (United States)

    Guo, Dong-cai; Yi, Li-ming; Shu, Wan-gen; Zhang, Zhen-zhen; Zeng, Zhao-rong; Zhang, Xi-qian

    2006-11-01

    Five ternary complexes were synthesized from europium with aromatic carboxylic acid (p-methylbenzoic acid, methoxybenzoic acid, m-chlorobenzoic acid and benzoic acid, p-hydroxylbenzoic acid) and acrylonitrile, and characterized by means of elemental analysis, thermal analysis, FTIR spectra and UV spectra. The fluorescence spectra show that five ternary complexes have good luminescence properties, and the sequence of the ability of the aromatic carboxylic acids to transfer light energy to europium ion is as follows: p-methylbenzoic acid>benzoic acid>m-chlorobenzoic acid>p-hydroxylbenzoic acid>methoxybenzoic acid. Meanwhile, the ternary europium complexes containing a reactive ligand acrylonitrile will possibly have a potential application to the fabrication of bonding-type europium polymer luminescent materials.

  9. Optical characterization of europium-doped indium hydroxide nanocubes obtained by Microwave-Assisted Hydrothermal method

    OpenAIRE

    Motta, Fabiana Villela da; Marques,Ana Paula de Azevedo; Araújo,Vinícius Dantas de; Tavares, Mara Tatiane De Souza; Delmonte,Mauricio Roberto Bomio; Paskocimas, Carlos Alberto; Li, Máximo Siu; Nascimento, Rubens Maribondo do; Longo, Elson [UNESP

    2014-01-01

    Crystalline europium-doped indium hydroxide (In(OH)3:Eu) nanostructures were prepared by rapid and efficient Microwave-Assisted Hydrothermal (MAH) method. Nanostructures were obtained at low temperature. FE-SEM images confirm that these samples are composed of 3D nanostructures. XRD, optical diffuse reflectance and photoluminescence (PL) measurements were used to characterize the products. Emission spectra of europium-doped indium hydroxide (IH:xEu) samples under excitation (350.7 nm) present...

  10. Structural and optical properties of europium doped zirconia single crystals fibers grown by laser floating zone

    OpenAIRE

    Soares, M.R.N.; Nico, C.; Peres, M.; Ferreira, N.; Fernandes, A.J.S.; Monteiro, T.; COSTA, F.M.

    2011-01-01

    Yttria stabilized zirconia single crystal fibers doped with europium ions were developed envisaging optical applications. The laser floating zone technique was used in order to grow millimetric high quality single crystal fibers. The as-grown fibers are completely transparent and inclusion free, exhibiting a cubic structure. Under ultraviolet (UV) excitation, a broad emission band appears at 551 nm. The europium doped fibers are translucent with a tetragonal structure and exhibit an intense r...

  11. A non-aqueous reduction process for purifying ¹⁵³Gd produced in natural europium targets.

    Science.gov (United States)

    Johnsen, Amanda M; Soderquist, Chuck Z; McNamara, Bruce K; Fisher, Darrell R

    2013-12-01

    Gadolinium-153 is a low-energy gamma-emitter used in nuclear medicine imaging quality assurance. Produced in nuclear reactors using natural Eu₂O₃ targets, ¹⁵³Gd is radiochemically separated from europium isotopes by europium reduction. However, conventional aqueous europium reduction produces hydrogen gas, a flammability hazard in radiological hot cells. We altered the traditional reduction method, using methanol as the process solvent to nearly eliminate hydrogen gas production. This new, non-aqueous reduction process demonstrates greater than 98% europium removal and gadolinium yields of 90%. © 2013 Elsevier Ltd. All rights reserved.

  12. Intercalated europium metal in epitaxial graphene on SiC

    Science.gov (United States)

    Anderson, Nathaniel A.; Hupalo, Myron; Keavney, David; Tringides, Michael C.; Vaknin, David

    2017-10-01

    X-ray magnetic circular dichroism (XMCD) reveals the magnetic properties of intercalated europium metal under graphene on SiC(0001). The intercalation of Eu nanoclusters (average size 2.5 nm) between graphene and SiC substate are formed by deposition of Eu on epitaxially grown graphene that is subsequently annealed at various temperatures while keeping the integrity of the graphene layer. Using sum-rules analysis of the XMCD of Eu M4 ,5 edges at T =15 K, our samples show paramagnetic-like behavior with distinct anomaly at T ≈90 K, which may be related to the Nèel transition, TN=91 K, of bulk metal Eu. We find no evidence of ferromagnetism due to EuO or antiferromagnetism due to Eu2O3 , indicating that the graphene layer protects the intercalated metallic Eu against oxidation over months of exposure to atmospheric environment.

  13. 9 CFR 156.1 - Meaning of words.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Meaning of words. 156.1 Section 156.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Meaning of words. Words used in this part in the singular form shall import the plural, and vice versa, as...

  14. 49 CFR 173.156 - Exceptions for ORM materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Exceptions for ORM materials. 173.156 Section 173... for Hazardous Materials Other Than Class 1 and Class 7 § 173.156 Exceptions for ORM materials. (a... this part. (b) ORM-D. Packagings for ORM-D materials are specified according to hazard class in §§ 173...

  15. 40 CFR 417.156 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 417.156 Section 417.156 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Manufacture of Spray Dried...

  16. 40 CFR 721.9511 - Silicic acid (H6SiO2O7), magnesium, strontium salt(1:1:2), dysprosium and europium-doped.

    Science.gov (United States)

    2010-07-01

    ..., strontium salt(1:1:2), dysprosium and europium-doped. 721.9511 Section 721.9511 Protection of Environment...), magnesium, strontium salt(1:1:2), dysprosium and europium-doped. (a) Chemical substance and significant new..., strontium salt(1:1:2), dysprosium and europium-doped. (PMN P-98-848; CAS No.181828-07-9) is subject to...

  17. Fluorescent lifetime imaging microscopy using Europium complexes improves atherosclerotic plaques discrimination.

    Science.gov (United States)

    Sicchieri, Letícia Bonfante; de Andrade Natal, Rodrigo; Courrol, Lilia Coronato

    2016-10-01

    The objective of this study is to characterize arterial tissue with and without atherosclerosis by fluorescence lifetime imaging microscopy (FLIM) using Europium Chlortetracycline complex (EuCTc) as fluorescent marker. For this study, twelve rabbits were randomly divided into a control group (CG) and an experimental group (EG), where they were fed a normal and hypercholesterolemic diet, respectively, and were treated for 60 days. Cryosections of the aortic arch specimens were cut in a vertical plane, mounted on glass slides, and stained with Europium (Eu), Chlortetracycline (CTc), Europium Chlortetracycline (EuCTc), and Europium Chlortetracycline Magnesium (EuCTcMg) solutions. FLIM images were obtained with excitation at 405 nm. The average autofluorescence lifetime within plaque depositions was ~1.36 ns. Reduced plaque autofluorescence lifetimes of 0.23 and 0.31 ns were observed on incubation with EuCTc and EuCTcMg respectively. It was observed a quenching of collagen, cholesterol and TG emission spectra increasing EuCTc concentration. The drastic reduction in fluorescence lifetimes is due to a resonant energy transfer between collagen, triglycerides, cholesterol and europium complexes, quenching fluorescence.

  18. Visible-light sensitized luminescent europium(III)-β-diketonate complexes: bioprobes for cellular imaging.

    Science.gov (United States)

    Reddy, M L P; Divya, V; Pavithran, Rani

    2013-11-21

    Visible-light sensitized luminescent europium(III) molecular materials are of considerable importance because their outstanding photophysical properties make them well suited as labels in fluorescence-based bioassays and low-voltage driven pure red-emitters in optoelectronic technology. One challenge in this field is development of visible-light sensitizing ligands that can form highly emissive europium(III) complexes with sufficient stability and aqueous solubility for practical applications. Indeed, some of the recent reports have demonstrated that the excitation-window can be shifted to longer-wavelengths in europium(III)-β-diketonate complexes by appropriate molecular engineering and suitably expanded π-conjugation in the complex molecules. In this review, attention is focused on the latest innovations in the syntheses and photophysical properties of visible-light sensitized europium(III)-β-diketonate complexes and their application as bioprobes for cellular imaging. Furthermore, luminescent nanomaterials derived from long-wavelength sensitized europium(III)-β-diketonate complexes and their application in life sciences are also highlighted.

  19. The electronic properties of mixed valence hydrated europium chloride thin film.

    Science.gov (United States)

    Silly, M G; Charra, F; Lux, F; Lemercier, G; Sirotti, F

    2015-07-28

    We investigate the electronic properties of a model mixed-valence hydrated chloride europium salt by means of high resolution photoemission spectroscopy (HRPES) and resonant photoemission spectroscopy (RESPES) at the Eu 3d → 4f and 4d → 4f transitions. From the HRPES spectra, we have determined that the two europium oxidation states are homogeneously distributed in the bulk and that the hydrated salt film is exempt from surface mixed valence transition. From the RESPES spectra, the well separated resonant contributions characteristic of divalent and trivalent europium species (4f(6) and 4f(7) final states, respectively) are accurately extracted and quantitatively determined from the resonant features measured at the two edges. The partial absorption yield spectra, obtained by integrating the photoemission intensity in the valence-band region, can be well reproduced by atomic multiplet calculation at the M(4,5) (3d-4f) absorption edge and by an asymmetric Fano-like shape profile at the N(4,5) (4d-4f) absorption edge. The ratio of Eu(2+) and Eu(3+) species measured at the two absorption edges matches with the composition of the mixed valence europium salt as determined chemically. We have demonstrated that the observed spectroscopic features of the mixed valence salt are attributed to the mixed-valence ground state rather than surface valence transition. HRPES and RESPES spectra provide reference spectra for the study of europium salts and their derivatives.

  20. Europium-doped calcium titanate: Optical and structural evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Mazzo, Tatiana Martelli; Pinatti, Ivo Mateus [INCTMN, LIEC, Departamento de Química, Universidade Federal de São Carlos, P.O. Box 676, 13565-905 São Carlos, SP (Brazil); Macario, Leilane Roberta [INCTMN, LIEC, Instituto de Química, Universidade Estadual Paulista, P.O. Box 355, 14800-900 Araraquara, SP (Brazil); Avansi, Waldir [Centro de Ciências Exatas e de Tecnologia, Departamento de Física, Universidade Federal de São Carlos, Jardim Guanabara, 13565-905 São Carlos, SP (Brazil); Moreira, Mario Lucio [Instituto de Física e Matemática, Universidade Federal de Pelotas, P.O. Box 354, Campus do Capão do Leão, 96001-970 Pelotas, RS (Brazil); Rosa, Ieda Lucia Viana, E-mail: ilvrosa@ufscar.br [INCTMN, LIEC, Departamento de Química, Universidade Federal de São Carlos, P.O. Box 676, 13565-905 São Carlos, SP (Brazil); Mastelaro, Valmor Roberto [Instituto de Física de São Carlos, Departamento de Física e Ciência dos Materiais, Universidade de São Paulo, P.O. Box 369, Av Trabalhador São Carlense 400, 13560-970 São Carlos, SP (Brazil); Varela, José Arana; Longo, Elson [INCTMN, LIEC, Instituto de Química, Universidade Estadual Paulista, P.O. Box 355, 14800-900 Araraquara, SP (Brazil)

    2014-02-05

    Highlights: • CaTiO{sub 3}:Eu{sup 3+} were obtained using low temperatures and very short reactional times. • The Eu{sup 3+} changes the local order–disorder of the [TiO{sub 6}] and [CaO{sub 12}] clusters. • Lifetime decay curves reveal two sites of symmetry of the Eu{sup 3+} in the CT matrix. • CaTiO{sub 3}:Eu{sup 3+} exhibit the strongest luminescent intensity and pure red color. -- Abstract: Pure Calcium Titanate (CT-pure) and Europium doped Calcium Titanate Ca{sub 1−x}Eu{sub x}TiO{sub 3} (x = 0.5%, 1.0% and 2.0% molar ratio of Eu{sup 3+} ions) powders were synthesized by hydrothermal microwave method (HTMW) at 140 °C for 8 min. The HTMW method appears to be an efficient method to prepare the luminescence materials using low temperatures and very short reactional times. In addition it is possible to determine specific correlations imposed by TiCl{sub 4} replacement by titanium isopropoxide [Ti(OC{sub 3}H{sub 7}){sub 4}] changing the reaction character and resulting in two different options of europium doping CT syntesis. To evaluate the influence of the structural order–disorder among the reactions and different properties of these materials, the following techniques were used for characterization. XANES spectroscopy that revealed that the introduction of Eu{sup 3+} ions into the CT lattice induces to significant changes in the local order–disorder around both, [TiO{sub 6}] and [CaO{sub 12}], complex clusters. PL spectra show Eu{sup 3+} emission lines ascribed to the Eu{sup 3+} transitions from {sup 5}D{sub 0} excited states to {sup 7}F{sub J} (J = 0, 1–4) fundamental states in CT:Eu{sup 3+} powders excited at 350 and 394 nm.

  1. 156 Viviendas Industrializadas en Vitoria-Gasteiz

    Directory of Open Access Journals (Sweden)

    López del Corral, J. J.

    2009-03-01

    Full Text Available In 2004, VISESA announced a Grant for Research on Industrialized Housing Structures that was awarded to the Pich-Aguilera team. Their survey identified a series of energy-related, social and economic aspects in modern construction that could be optimized by system industrialization. * System assessed in the survey: – Facade cladding. – Frame (columns and beams. – Three-dimensional aspects (horizontal/vertical surfaces, standard rooms, modules. – Composite construction in frame, cladding and modules.* Analysis of construction contracting, associations and companies. * Comparative analysis of industrialized and traditional construction. Taking the theoretical data and conclusions of the survey funded by the grant as a basis, and in light of the industrialization strategy laid down in the Basque Country Regional Government’s Housing Guidelines and VISESA’s Strategic and Management Plans, concrete manufacturers in the Basque Country and surrounding autonomous communities were contacted to determine the industrial feasibility of a specific construction project. With these findings in hand, the research grant was extended to include a specific architectural design: 156 housing units on lot RC.33 in Sector 6 at Zabalgana, Vitoria-Gasteiz, whose main characteristics are: – G+8+penthouse, doubling the height of isostatic concrete buildings erected in Spain to date. – Industrialized structure and enclosures (3-storey columns, isostatic portal frames stiffened with steel tie rods and slab topping. – Curved steel roof and steel joints between columns (high strength bolts. – Industrialized construction system (process, not only as the sum of elements, but minimizing material and energy consumption, raising the guarantee of final finish quality and improving working conditions and site safety. The construction design (PICH-AGUILERA and structure by BOMA was concluded with construction solutions NOT dependent upon specific patents; the

  2. RBS and RNRA studies on sorption of europium by apatite

    Energy Technology Data Exchange (ETDEWEB)

    Ohnuki, Toshihiko; Kozai, Naofumi; Isobe, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Murakami, Takashi; Yamamoto, Shunya; Aoki, Yasushi; Naramoto, Hiroshi

    1997-03-01

    The sorption mechanism of europium, alternative of trivalent TRU has been studied based on the depth profiles of elements obtained by Rutherford Backscattering Spectroscopy (RBS) and Resonant Nuclear Reaction Analysis (RNRA). The positive peak for Eu and the negative peak for Ca were observed in the subtracted RBS spectra of the apatites on which Eu was sorbed from that of the fresh apatite. This indicates that Eu was sorbed on apatite, while a fraction of Ca was released from apatite. The peak height for Eu in the RBS spectrum of the apatite obtained at 75degC was higher than that of the apatite at 40degC. The depth profile of hydrogen of the apatite on which Eu was sorbed was similar to that of the fresh apatite. The concentration of Eu in the solution decreased with increasing temperature. On the contrary, the concentration of Ca increased with increasing temperature. Thus, it is concluded that a fraction of Eu is exchanged for Ca in the structure of apatite. (author)

  3. Spectrofluorimetric determination of heparin using doxycycline-europium probe

    Energy Technology Data Exchange (ETDEWEB)

    Li Jing [Department of Chemistry, Shandong Normal University, Jinan 250014 (China); Liu Jinkai [Department of Chemistry, Shandong Normal University, Jinan 250014 (China); Zhu Xiaojing [Department of Chemistry, Shandong Normal University, Jinan 250014 (China); Peng Qian [Department of Chemistry, Shandong Normal University, Jinan 250014 (China); Jiang Chongqiu [Department of Chemistry, Shandong Normal University, Jinan 250014 (China)]. E-mail: jiangchongqiu@sdnu.edu.cn

    2005-06-15

    A new spectrofluorimetric method was developed for the determination of the trace amount of heparin (Hep). Using doxycycline (DC)-europium ion (Eu{sup 3+}) as a fluorescent probe, in the buffer solution of pH=8.9, Hep can remarkably enhance the fluorescence intensity of the DC-Eu{sup 3+} complex at {lambda}=612 nm and the enhanced fluorescence intensity of Eu{sup 3+} ion is in proportion to the concentration of Hep. Optimum conditions for the determination of Hep were also investigated. The linear range and detection limit for the determination of Hep are 0.04-0.8 {mu}g/mL and 19.7 ng/mL, respectively. This method is simple, practical, and relatively free of interference from coexisting substances and can be successfully applied to assess Hep in biological samples. By the Rosenthal graphic method, the association constant and binding numbers of Hep with the probe are 6.60x10{sup 4} L/mol and 33.9. Moreover, the enhancement mechanism of the fluorescence intensity in the DC-Eu{sup 3+} system and the DC-Eu{sup 3+}-Hep-CTMAB system have been also discussed.

  4. Extraction of americium and europium by CMPO-substituted adamantylcalixarenes

    Energy Technology Data Exchange (ETDEWEB)

    Babain, V.A.; Alyapyshev, M.Yu.; Karavan, M.D. [V.G. Khlopin Radium Inst., St. Petersburg (Russian Federation); Boehmer, V.; Wang, L. [Johannes Guttenberg Univ., Mainz (Germany); Shokova, E.A.; Motornaya, A.E.; Vatsouro, I.M.; Kovalev, V.V. [M. V. Lomonosov Moscow State Univ., Moscow (Russian Federation)

    2005-07-01

    Eight p-adamantylcalix[4]arene derivatives, bearing four CMPO-like functions [-(CH{sub 2}){sub n}-NH-C(O)-CH{sub 2-}P(O)Ph{sub 2}] at the wide (4a,b, n = 0, 1) or narrow (5a-c and 6a-c, n = 2-4) rims were synthesized for the first time. Studies of the extraction of americium(III) and europium(III) from 3 M HNO{sub 3} solutions to organic phases (dichloromethane, m-nitro-trifluoromethylbenzene) showed: (i) The extraction ability for all the adamantylcalixarene ligands is much better than for their monomeric analogues -N-(1-adamantyl)-, N-(1-adamantylmethyl)- and N,N-(dibutyl)carbamoylmethyldiphenylphosphine oxides 7a, 7b, 8; (ii) The extraction percentage increases strongly with increasing length of the spacer for all types of ligands 4-6, and best extraction results were found for 4b (n = 1) and 5c (n = 4); (iii) The separation coefficient D{sub Am}/D{sub Eu} for the investigated compounds did not exceed 2, which is close to the narrow rim CMPO calixarenes, studied earlier; (iv) Variation of the spacer length between CMPO groups attached to the 1,3- and 2,4-positions of the calixarene platform in 6 did not lead to appreciably improved extractants, neither with respect to the extraction abilities (D) nor to the selectivities (D{sub Am}/D{sub Eu}). (orig.)

  5. Preparation of europium-labelled DNA probes and their properties.

    Science.gov (United States)

    Hurskainen, P; Dahlén, P; Ylikoski, J; Kwiatkowski, M; Siitari, H; Lövgren, T

    1991-01-01

    A chemical method for labelling DNA with a europium chelate is presented. First, primary aliphatic amino groups are introduced onto DNA in a transamination reaction. The transamination reaction is altered by adjusting temperature and duration of the reaction. Subsequently, the modified DNA is reacted with an isothiocyanate derivative of a Eu chelate. The optimum amount of Eu chelates on a DNA probe is 4-8% of total nucleotides. There is a decrease of 0.7 degrees C in the melting temperature of DNA for each incorporated Eu chelate on 100 bases. Hybridization efficiency is lowered by the introduction of Eu chelates but this effect can be partly overcome by using high DNA probe concentrations. The detection limit of the Eu-labelled probe is 0.15 attomoles of target DNA in a mixed-phase hybridization assay on microtitration wells. In addition to high sensitivity the Eu-labelled probes offer convenience in use and results which are quantitative and easy to interpret. PMID:1826948

  6. Chloride, bromide and iodide scintillators with europium doping

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2014-08-26

    A halide scintillator material is disclosed where the halide may comprise chloride, bromide or iodide. The material is single-crystalline and has a composition of the general formula ABX.sub.3 where A is an alkali, B is an alkali earth and X is a halide which general composition was investigated. In particular, crystals of the formula ACa.sub.1-yEu.sub.yI.sub.3 where A=K, Rb and Cs were formed as well as crystals of the formula CsA.sub.1-yEu.sub.yX.sub.3 (where A=Ca, Sr, Ba, or a combination thereof and X=Cl, Br or I or a combination thereof) with divalent Europium doping where 0.ltoreq.y.ltoreq.1, and more particularly Eu doping has been studied at one to ten mol %. The disclosed scintillator materials are suitable for making scintillation detectors used in applications such as medical imaging and homeland security.

  7. Spectrofluorimetric determination of lecithin using a tetracycline-europium probe

    Energy Technology Data Exchange (ETDEWEB)

    Wang Ting [Department of Chemistry, Shandong Normal University, Jinan, Shandong 250014 (China); Jiang Chongqiu [Department of Chemistry, Shandong Normal University, Jinan, Shandong 250014 (China)]. E-mail: jiangchongqiu@sdnu.edu.cn

    2006-03-02

    Trace amount of lecithin (PC) was determined in the buffer solution of pH 5.7, using tetracycline (TC)-europium ion (Eu{sup 3+}) as a fluorescent probe. PC can remarkably enhance the fluorescence intensity of the TC-Eu{sup 3+} complex at {lambda} = 612 nm and the enhanced fluorescence intensity of Eu{sup 3+} is in proportion to the concentration of PC. Optimum conditions for the determination of PC were also investigated. The linear range and detection limit for the determination of PC are 4.0 x 10{sup -7} to 1.4 x 10{sup -5} mol/L and 3.9 x 10{sup -8} mol/L. This method is simple, practical and relatively free of interference from coexisting substances and can be successfully applied to assess PC in serum samples. Moreover, the enhancement mechanism of the fluorescence intensity in the TC-Eu{sup 3+} system, the TC-Eu{sup 3+}-PC system, and the TC-Eu{sup 3+}-PC-sodium dodecyl benzene sulfonate (SDS) system is also discussed.

  8. Artifacts in the determination of the binding of americium and europium to an aquatic fulvic acid

    Energy Technology Data Exchange (ETDEWEB)

    Lead, J.R.; Hamilton-Taylor, J.; Kelly, M. [Institute of Environmental and Biological Sciences, Lancaster University, Lancaster (United Kingdom)

    1995-11-23

    The binding of europium and americium by an aquatic fulvic acid was investigated using an equilibrium ion exchange technique (Schubert`s method). The results for europium were consistent with literature data. Americium gave anomalous results for both the D{sub o} values (partition coefficient of the metal between the resin and solution phases in the absence of the fulvic acid) and D values (partition coefficient of the metal between the resin and solution phases in the presence of the fulvic acid). The values for americium were unexpectedly low and, in the case of D values, only slightly pH dependent. The cause of the discrepancy was found to be the partial dissolution of the resin or the loss of small colloidal material from the resin. The effects on the europium results were minimal due to the use of lower resin weights and higher metal concentrations

  9. Synthesis and luminescence properties of 2-(benzylcarbamoyl)phenyl derivatives and their europium complexes.

    Science.gov (United States)

    Guo, Dongcai; He, Wei; Liu, Bang; Gou, Lining; Li, Ruixia

    2013-01-01

    Six novel 2-(benzylcarbamoyl)phenyl derivatives were synthesized and characterized by (1) H-NMR, mass spectrometry, infrared spectra and elemental analysis. Their europium complexes were prepared and characterized by elemental analysis, EDTA titrimetric analysis, IR and UV spectra as well as molar conductivity measurements. The luminescence properties of these complexes were investigated and results show that 2-(benzylcarbamoyl)phenyl derivatives possess high selectivity and good coordination with the europium ion. Complex Eu-2-(benzylcarbamoyl)phenyl-2-phenylacetate showed green luminescence that was emitted by the ligand of 2-(benzylcarbamoyl)phenyl-2-phenylacetate, while other complexes showed the characteristic red luminescence of europium ion and also possessed high luminescence intensity. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Induction of Circularly Polarized Luminescence from Europium by Amino Acid Based Ionic Liquids.

    Science.gov (United States)

    Zercher, Ben; Hopkins, Todd A

    2016-11-07

    Materials that emit circularly polarized light have application in several important industries. Because they show large optical activity and emit sharp visible light transitions, europium complexes are often exploited in applications that require circularly polarized luminescence (CPL). Chiral and coordinating ionic liquids based on prolinate, valinate, and aspartate anions are used to induce CPL from a simple achiral europium triflate salt. The sign of the induced CPL is dependent on the handedness (l vs d) of the amino acid anion. Comparison of the CPL spectra in ionic liquid with proline and valine vs aspartate shows that the number of carboxylate groups in the amino acid anion influences the europium coordination environment. DFT calculations predict a chiral eight-coordinate Eu(Pro)4- structure in the prolinate ionic liquid and a chiral seven- or eight-coordinate Eu(Asp)33- structure in the aspartate ionic liquid.

  11. Comparative analysis of conjugated alkynyl chromophore-triazacyclononane ligands for sensitized emission of europium and terbium.

    Science.gov (United States)

    Soulié, Marine; Latzko, Frédéric; Bourrier, Emmanuel; Placide, Virginie; Butler, Stephen J; Pal, Robert; Walton, James W; Baldeck, Patrice L; Le Guennic, Boris; Andraud, Chantal; Zwier, Jurriaan M; Lamarque, Laurent; Parker, David; Maury, Olivier

    2014-07-07

    A series of europium and terbium complexes based on a functionalized triazacyclononane carboxylate or phosphinate macrocyclic ligand is described. The influence of the anionic group, that is, carboxylate, methylphosphinate, or phenylphosphinate, on the photophysical properties was studied and rationalized on the basis of DFT calculated structures. The nature, number, and position of electron-donating or electron-withdrawing aryl substituents were varied systematically within the same phenylethynyl scaffold in order to optimize the brightness of the corresponding europium complexes and investigate their two-photon absorption properties. Finally, the europium complexes were examined in cell-imaging applications, and selected terbium complexes were studied as potential oxygen sensors. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Magnetic and structural properties of yellow europium oxide compound and Eu(OH){sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dongwook, E-mail: dongwookleedl324@gmail.com [Cavendish Laboratory, University of Cambridge, J. J Thomson Av., Cambridge CB3 0HE (United Kingdom); Seo, Jiwon, E-mail: jiwonseo@yonsei.ac.kr [Department of Physics and IPAP, Yonsei University, Seoul 120-749 (Korea, Republic of); Valladares, Luis de los Santos [Cavendish Laboratory, University of Cambridge, J. J Thomson Av., Cambridge CB3 0HE (United Kingdom); Avalos Quispe, O. [Laboratorio de Cerámicos y Nanomateriales, Facultad de Ciencias Físicas, Universidad Nacional Mayor de San Marcos, Ap. Postal 14-0149, Lima, Perú (Peru); Barnes, Crispin H.W. [Cavendish Laboratory, University of Cambridge, J. J Thomson Av., Cambridge CB3 0HE (United Kingdom)

    2015-08-15

    A new material based on a yellow europium oxide compound was prepared from europium oxide in a high vacuum environment. The structural and magnetic properties of the material were investigated. Owing to the absence of a crystal structure, the material exhibited a disordered magnetic behavior. In a reaction with deionized (DI) water without applied heat, the compound assumed a white color as soon as the DI water reached the powder, and the structure became polycrystalline Eu(OH){sub 3}. The magnetic properties, such as the thermal hysteresis, disappeared after the reaction with DI water, and the magnetic susceptibility of the yellow oxide compound weakened. The magnetic properties of Eu(OH){sub 3} were also examined. Although Eu{sup 3+} is present in Eu(OH){sub 3}, a high magnetic moment due to the crystal field effect was observed. - Graphical abstract: (top left) Optical image of the yellow europium oxide compound. (top right) Optical image of the product of DI water and yellow europium oxide. (bottom) Magnetization curves as a function of temperature measured in various magnetic field. - Highlights: • We prepared a new material based on a yellow europium oxide compound from europium oxide. • We characterized the magnetic properties of the material which exhibits a disordered magnetic behavior such as thermal hysteresis. • The compound turned white (Eu(OH){sub 3}) as soon as the DI water reached the powder. • The thermal hysteresis disappeared after the reaction with DI water and the magnetic susceptibility of the yellow oxide compound weakened.

  13. Europium stearate additives delay oxidation of UHMWPE for orthopaedic applications: a pilot study.

    Science.gov (United States)

    Gallardo, Luis A; Carpentieri, Ilenia; Laurent, Michel P; Costa, Luigi; Wimmer, Markus A

    2011-08-01

    Ultrahigh-molecular-weight polyethylene (UHMWPE) is used as an articulating surface in prosthetic devices. Its failure under various mechanisms after oxidation is of utmost concern. Free radicals formed during the sterilization process using high-energy irradiation result in oxidation. Europium, an element of the lanthanide family, has a unique electron configuration with an unusual lack of preference for directional bonding and notable bonding to oxygen. Because of this, it currently is used in studies for stabilization of polymers such as polyvinyl chloride. We asked whether europium stearate could enhance the oxidation resistance after irradiation in nitrogen of UHMWPE. Conventional nonirradiated and gamma-irradiated in nitrogen UHMWPE were compared with polyethylene doped with 375 ppm and 3750 ppm europium(III) stearate under the same treatment conditions. Chemical characterization was performed by Fourier transform infrared (FTIR) microspectroscopy using 200-μm thin films. The oxidation of doped samples with time was compared with that of conventional samples using accelerated oven aging. The types of oxidation products were identified by FTIR and quantified per material and treatment condition as indications of the oxidation level and mechanism. The generation rate of hydroperoxides and ketones was decelerated proportionally with concentration of europium stearates. The oxidative mechanism appeared similar to that of conventional polyethylene with the same types of measurable end products as ketones and hydroperoxides. Yet, the rate of generation of the latter appeared to be slowed down by the action of europium stearate. Europium stearate mixed in UHMWPE decelerated the oxidation reactions triggered by gamma irradiation in nitrogen, seemingly without major alteration of the oxidation mechanism.

  14. Single crystal growth of europium and ytterbium based intermetallic ...

    Indian Academy of Sciences (India)

    to dissolve the excess metal flux. Due to its low melting temperature of 156.6. ◦. C, indium is an ideal metal for use as a reactive flux (self- flux condition). It has widely been used for the synthe- sis and crystal growth of indium-rich binary and ternary indides. In many cases, a slight excess of indium sig- nificantly increases the ...

  15. Temperature dependent luminescence of a europium complex incorporated in poly(methyl methacrylate).

    Science.gov (United States)

    Liang, Hao; Xie, Fang; Ren, Xiaojun; Chen, Yifa; Chen, Biao; Guo, Fuquan

    2013-12-01

    An europium β-diketonate complex with a dipyrazolyltriazine derivative ligand, Eu(TTA)3DPBT, has been incorporated into poly(methyl methacryate) (PMMA). The influence of temperature on its luminescence properties has been investigated. The fluorescence emission spectra and luminescence lifetimes showed temperature sensitivity. The analysis of the relative intensity ratio (R) of (5)D0 → (7)F2 to (5)D0 → (7)F1 transition and Judd-Ofelt experimental intensity parameters Ω2 indicated that the local structure and asymmetry in the vicinity of europium ions show no obvious change when the temperature is increased. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Study of the europium behavior in aqueous media; Estudio sobre el comportamiento del europio en medios acuosos

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez R, E.; Jimenez R, M.; Solache R, M.; Martinez M, V. [Instituto Nacional de Investigaciones Nucleares, Departamento de Quimica, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

    2000-07-01

    Europium as waste can produce a pollution problem in water that is in contact with it, what would has a heavy environmental impacts, because of the possibilities of diffusion of these wastes from their place of confinement or storage until the geo and biosphere. The solution of such problem requires of a lot of knowledge over the behavior of several chemical elements such as europium in aqueous solutions. In this work it was used a low ion force (0.02 M). The data set will allow extrapolate the hydrolytic behavior of europium in too much minors ion force media, such as the ground waters, including in ion force zero.

  17. Thermodynamic and structural description of europium complexation in 1-octanol - H{sub 2}O solutions

    Energy Technology Data Exchange (ETDEWEB)

    Vu, T.H.; Charbonnel, M.C.; Boubals, N.; Couston, L. [CEA Marcoule, DEN/DRCP/SCPS/LCAM, BP 17171, 30207 Bagnols-sur-Ceze (France); Arnaud, F. [Laboratoire de Chimie Physique, IPHC, 25 rue Becquerel, 67087 Strasbourg (France)

    2008-07-01

    Polydentate N-bearing ligands such as bis-triazinyl-pyridines (BTPs) are interesting extractants for actinide(III)/lanthanide(III) separation. A description of europium complexation in 1-octanol solutions was undertaken to enhance the knowledge of the extraction mechanisms. The first solvation shell for europium(III) nitrate, chloride, and perchlorate with different amounts of water was determined by Time-Resolved Laser-Induced Fluorescence (TRLIF) spectroscopy. Europium nitrate complexation by iPr-BTP was then studied by TRLIF and micro-calorimetry; similar stability constants related to the formation of Eu(BTP){sub 2}{sup 3+} and Eu(BTP){sub 3}{sup 3+} were obtained by both techniques (log({beta}{sub 2}) = 9.0 {+-} 0.3 and log({beta}{sub 3}) = 13.8 {+-} 0.2). The presence of water in the octanol diluent has an influence on solvation of europium and also on the [Eu(BTP){sub 2}{sup 3+}] / [Eu(BTP){sub 3}{sup 3+}] ratio. (authors)

  18. A novel biocompatible europium ligand for sensitive time-gated immunodetection.

    Science.gov (United States)

    Sayyadi, Nima; Connally, Russell E; Try, Andrew

    2016-01-21

    We describe the synthesis of a novel hydrophilic derivative of a tetradentate β-diketone europium ligand that was used to prepare an immunoconjugate probe against Giardia lamblia cysts. We used a Gated Autosynchronous Luminescence Detector (GALD) to obtain high quality delayed luminescence images of cells 30-fold faster than ever previously reported.

  19. Europium-doped barium halide scintillators for x-ray and ?-ray detections

    NARCIS (Netherlands)

    Selling, J.; Birowosuto, M.D.; Dorenbos, P.; Schweizer, S.

    2007-01-01

    Single crystals of undoped or europium-doped barium chloride, bromide, and iodide were investigated under x-ray and ?-ray excitations. The Eu2+-related x-ray excited luminescence found in the Eu-doped barium halides occurs at 402, 404, and 425?nm for the chloride, bromide, and iodide, respectively.

  20. A europium luminescence assay of lactate and citrate in biological fluids†

    Science.gov (United States)

    Pal, Robert; Costello, Leslie C.

    2013-01-01

    Ratiometric methods of analysis have been developed for the selective determination of lactate or citrate in microlitre samples of human serum, urine or prostate fluids following comparison of anion binding affinities for a family of nine luminescent europium(III) complexes. PMID:19343236

  1. Molecular interactions of Leucoagaricus naucinus with uranium(VI) and europium(III)

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, Anne; Raff, Johannes [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry; Guenther, A. [Helmholtz Institute Freiberg for Resource Technology, Freiberg (Germany)

    2017-06-01

    With regard to a molecular understanding of the interaction of fungal mycelium with radionuclides and its possible application for precautionary radiation protection and bio-remediation, the binding mechanism of the radionuclide uranium and the metal europium, as surrogate for trivalent actinides, where investigated with different starting conditions by the living fungal cells of Leucoagaricus naucinus.

  2. Europium doped In(Zn)P/ZnS colloidal quantum dots

    NARCIS (Netherlands)

    Thuy, Ung Thi Dieu; Maurice, Axel; Liem, Nguyen Quang; Reiss, Peter

    2013-01-01

    Chemically synthesised In(Zn)P alloy nanocrystals are doped with Eu(3+) ions using europium oleate as a molecular precursor and are subsequently covered with a ZnS shell. The presence of zinc in the synthesis of the InP core nanocrystals leads to the formation of an In(Zn)P alloy structure, making

  3. NO fluorescence sensing by europium tetracyclines complexes in the presence of H2O2.

    Science.gov (United States)

    Simões, Eliana F C; Leitão, João M M; Esteves da Silva, Joaquim C G

    2013-07-01

    The effect on the fluorescence of the europium:tetracycline (Eu:Tc), europium:oxytetracycline (Eu:OxyTc) and europium:chlortetracycline (Eu:ClTc) complexes in approximately 2:1 ratio of nitric oxide (NO), peroxynitrite (ONOO(-)), hydrogen peroxide (H2O2) and superoxide (O2 (·-)) was assessed at three ROS/RNS concentrations levels, 30 °C and pH 6.00, 7.00 and 8.00. Except for the NO, an enhancement of fluorescence intensity was observed at pH 7.00 for all the europium tetracyclines complexes-the high enhancement was observed for H2O2. The quenching of the fluorescence of the Tc complexes, without and with the presence of other ROS/RNS species, provoked by NO constituted the bases for an analytical strategy for NO detection. The quantification capability was evaluated in a NO donor and in a standard solution. Good quantification results were obtained with the Eu:Tc (3:1) and Eu:OxyTc (4:1) complexes in the presence of H2O2 200 μM with a detection limit of about 3 μM (Eu:OxyTc).

  4. Long-term tagging of elvers, Anguilla anguilla, with radioactive europium

    DEFF Research Database (Denmark)

    Hansen, Heinz Johs. Max; Fattah, A. T. A.

    1986-01-01

    -life of added europium of 1.6 .+-. 0.5 years. Thirteen hundred 155Eu-labelled elvers (50 Bq per eel), each weighing on average 0.21 g, were set out near Oskarshamn on the east coast of Sweden in June 1982. Three of these were caught nearby in May 1985 and one was caught in August 1985. They weighed...

  5. ULTRAVIOLET TRANSITIONS IN EUROPIUM STUDIED WITH A FREQUENCY-DOUBLED CW RING DYE-LASER

    NARCIS (Netherlands)

    Eliel, E.R.; Hogervorst, W.; van Leeuwen, K.A.H.; Post, B.H.

    1981-01-01

    High resolution laser spectroscopy has been applied to the study of three ultraviolet transitions in Europium at λ = 294.8, 295.1 and 295.8 nm. The tunable narrowband UV has been generated by intracavity frequency doubling in a cw ring dye laser using a temperate tuned, Brewster angled ADA crystal.

  6. Optical and Morphological Characterization of Sonochemically Assisted Europium Doped Copper (I) Oxide Nanostructures

    Science.gov (United States)

    Cosico, J. A. M.; Ruales, P. K.; Marquez, M. C.

    2017-06-01

    In the age where application of nanotechnology in our society has proven to be eminent, different routes of synthesizing nanoparticles have emerged. In this study nanoparticles of cuprous oxide (Cu2O) doped with different amounts of europium was prepared by using solution precursor route approach with the aid of ultrasonic sound. Copper sulphate and europium (III) nitrate pentahydrate was used as source for copper ions and europium ions respectively. X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FTIR) were used to elucidate the cubic crystal structure and organic impurities present on Cu2Onanoparticles. UV-Vis spectroscopy was used to determine the absorption spectrum of the nanoparticles in the wavelength range of 400nm to 700nm. The bandgap of the undoped and doped Cu2O were found to fall between 2.1eV - 2.3eV. Scanning Electron Microscopy (SEM) coupled with energy dispersive x-ray was used to observe the dendritic and rodlike morphology and the presence of europium in the synthesized Cu2O nanoparticles. The observed effect on the absorbance of Cu2O upon adding Eu and a facile way of synthesizing Cu2O nanoparticles could bring a positive impact on the production of functional devices for optoelectronic and energy applications.

  7. Occurrence of photoluminescence and onion like structures decorating graphene oxide with europium using sodium dodecyl sulfate surfactant

    Science.gov (United States)

    Cedeño, V. J.; Rangel, R.; Cervantes, J. L.; Lara, J.; Alvarado, J. J.; Galván, D. H.

    2017-07-01

    Graphene oxide decoration with europium was carried out using SDS (sodium dodecyl sulfate) as the surfactant. The reaction was performed in a microwave oven and subsequently underwent thermal treatment under hydrogen flow. The results found in the present work demonstrate that through the use of SDS surfactant aggregates of hemi-cylindrical and onion-like structures could be obtained; which propitiate an enhanced synergistic photoluminescence located at the red wavelength. On the other hand, after thermal treatment the aggregates disappear providing a good dispersion of europium, however a decrease in the photoluminescence signal is observed. The graphene oxide decorated with europium was characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier infrared transform spectroscopy (FTIR), RAMAN spectroscopy, x-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) techniques, showing the characteristic features of graphene oxide and europium.

  8. Synthesis, characterization, and properties of reduced europium molybdates and tungstates

    Energy Technology Data Exchange (ETDEWEB)

    Abeysinghe, Dileka [Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 (United States); Gerke, Birgit [Institut für Anorganische und Analytische Chemie, Universität Münster , Corrensstrasse 30, Münster D-48149 (Germany); Morrison, Gregory; Hsieh, Chun H.; Smith, Mark D. [Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 (United States); Pöttgen, Rainer [Institut für Anorganische und Analytische Chemie, Universität Münster , Corrensstrasse 30, Münster D-48149 (Germany); Makris, Thomas M. [Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 (United States); Loye, Hans-Conrad zur, E-mail: zurloye@mailbox.sc.edu [Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 (United States)

    2015-09-15

    Single crystals of K{sub 0.094}Eu{sub 0.906}MoO{sub 4}, K{sub 0.097}Eu{sub 0.903}WO{sub 4}, EuWO{sub 4}, and EuMoO{sub 4} were grown from molten chloride fluxes contained in vacuum-sealed fused silica and structurally characterized via single crystal X-ray diffraction. The in situ reduction of Eu{sup 3+} to Eu{sup 2+} was carried out using Mo, W, and Zn as metal reducing agents. All four compounds crystallize in the tetragonal space group of I4{sub 1}/a and adopt the scheelite (CaWO{sub 4}) structure type. The magnetic susceptibility of the reported compounds shows paramagnetic behavior down to 2 K. {sup 151}Eu Mössbauer spectroscopy was used to analyze the relative Eu{sup 2+} and Eu{sup 3+} content of the samples. All the compounds were further characterized by EPR, and UV-vis spectroscopy. - Graphical abstract: TOC Caption Two new reduced europium containing quaternary oxides, K{sub 0.094}Eu{sub 0.906}MoO{sub 4} and K{sub 0.097}Eu{sub 0.903}WO{sub 4}, and two previously reported ternary reduced oxides, EuWO{sub 4} and EuMoO{sub 4}, were synthesized via an in situ reduction of Eu{sup 3+} to Eu{sup 2+} under flux method using Mo, W, and Zn as metal reducing agents. {sup 151}Eu Mössbauer spectroscopy was used to analyze the relative Eu{sup 2+} and Eu{sup 3+} content of the samples. - Highlights: • K{sub 0.094}Eu{sub 0.906}MoO{sub 4}, K{sub 0.097}Eu{sub 0.903}WO{sub 4}, EuWO{sub 4}, and EuMoO{sub 4} have been synthesized and characterized. • The in situ reduction of Eu{sup 3+} to Eu{sup 2+} was carried out using Mo, W, and Zn as metal reducing agents. • Magnetic susceptibility data were collected. • {sup 151}Eu Mössbauer spectroscopy was used to analyze Eu{sup 2+} and Eu{sup 3+} content.

  9. A highly sensitive and selective fluorescent sensor for detection of Al(3+) using a europium(III) quinolinecarboxylate.

    Science.gov (United States)

    Xu, Wentao; Zhou, Youfu; Huang, Decai; Su, Mingyi; Wang, Kun; Hong, Maochun

    2014-07-07

    Eu2PQC6 has been developed to detect Al(3+) by monitoring the quenching of the europium-based emission, with the lowest detection limit of ∼32 pM and the quantitative detection range to 150 μM. Eu2PQC6 is the first ever example that the europium(III) complex serves as an Al(3+) fluorescent sensor based on "competition-displacement" mode.

  10. Phenotype abnormality: 156 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available 156 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u1ria224u662i decreased efficiency... in organ named root hair cell during process named 5 root hair formation stage ... root hair cell ... decreased efficiency ... 5 root hair formation stage ...

  11. 17 CFR 230.156 - Investment company sales literature.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Investment company sales... GENERAL RULES AND REGULATIONS, SECURITIES ACT OF 1933 General § 230.156 Investment company sales... is materially misleading in connection with the offer or sale of securities issued by an investment...

  12. 40 CFR 156.68 - First aid statement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false First aid statement. 156.68 Section... aid statement. (a) Product as sold and distributed. Each product must bear a first aid statement if... with water prior to use, the label may also include a statement describing how the first aid measures...

  13. 40 CFR 156.204 - Modification and waiver of requirements.

    Science.gov (United States)

    2010-07-01

    ... accordance with § 154.25(c) of this chapter that a pesticide should be placed in Special Review because the pesticide meets or exceeds the criteria for human health effects of § 154.7(a)(1)(2) or (6) of this chapter...) PESTICIDE PROGRAMS LABELING REQUIREMENTS FOR PESTICIDES AND DEVICES Worker Protection Statements § 156.204...

  14. 17 CFR 156.2 - Registration of broker association.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Registration of broker... BROKER ASSOCIATIONS § 156.2 Registration of broker association. (a) Registration required. It shall be unlawful for any member of a broker association to receive or to execute an order unless the broker...

  15. 17 CFR 156.4 - Disclosure of Broker Association Membership.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Disclosure of Broker... COMMISSION BROKER ASSOCIATIONS § 156.4 Disclosure of Broker Association Membership. Each contract market shall make available to the public generally and upon request a list of all registered broker...

  16. The effect of two additional Eu3+ lumophors in two novel trinuclear europium complexes on their photoluminescent properties.

    Science.gov (United States)

    Yang, Chaolong; Xu, Jing; Ma, Jianying; Zhu, Dongyu; Zhang, Yunfei; Liang, Liyan; Lu, Mangeng

    2013-02-01

    Two novel trinuclear europium complexes based on trisphen(1,3,5-tris{4-((1,10-phenanthroline-[5,6-d]imidazol-2yl)phenoxy)methyl}-2,4,6-trimethyl-benzene) as a second ligand were designed, synthesized, and characterized by FT-IR, (1)H NMR, UV-visible, photoluminescence (PL) spectroscopy, elemental analysis (EA) and ESI-MS. The geometries of these two trinuclear europium complexes were predicted using the Sparkle/PM3 model and suggested a chemical environment of very low symmetry around the lanthanide ions (C(1)), which is in agreement with the luminescent spectra. CV analysis demonstrated that the trinuclear complexes possessed excellent electro-injection abilities. The effects of two additional Eu(3+) lumophors in these trinuclear europium complexes on their photoluminescent properties were investigated in detail. The results indicated that these trinuclear europium complexes exhibited highly luminescent quantum efficiencies and experimental intensity parameters in the solid state. Especially, due to the contribution of the two additional Eu(3+) lumophors in the trinuclear europium complexes, the quantum efficiency of the trinuclear complex Eu(3)(TTA)(9)trisphen was higher (ca. 34%) than the mononuclear europium complex Eu(TTA)(3)imidazophen.

  17. Influence of biofilms on migration of uranium, americium and europium in the environment; Einfluss von Biofilmen auf das Migrationsverhalten von Uran, Americium und Europium in der Umwelt

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Nils; Zirnstein, Isabel; Arnold, Thuro

    2015-07-01

    The report on the influence of biofilms on migration of uranium, americium and europium in the environment deals with the contamination problems of uranium mines such as SDAG WISMUT in Saxonia and Thuringia. In mine waters microorganisms form a complex microbiological biocoenosis in spite of low pH values and high heavy metal concentrations including high uranium concentrations. The analyses used microbiological methods like confocal laser scanning microscopy and molecular-biological techniques. The interactions of microorganism with fluorescent radioactive heavy metal ions were performed with TRLFS (time resolved laser-induced fluorescence spectroscopy).

  18. Incorporation of europium III complex into nanoparticles and films obtained by the Sol-Gel methodology

    Directory of Open Access Journals (Sweden)

    Faley Jean de Sousa

    2010-03-01

    Full Text Available The sol-gel process is very effective for the preparation of new materials with potential applications in optics, sensors, catalyst supports, coatings, and specialty inorganic polymers that can be used as hosts for the accommodation of organic molecules. The low temperature employed in the process is the main advantage of this methodology. In this work, the europium (III complex with 1,10-phenantroline was prepared, and this luminescent complex was incorporated into silica nanoparticles and films by the sol-gel process. The nanoparticles were obtained by the modified Stöber methodology. The films were obtained by the dip-coating technique, at different deposition rates and numbers of layers. The nanoparticles and films were characterized by photoluminescence, thermal analysis, and Raman and infrared spectroscopies. Characterization revealed that the europium (III complex was not affected upon incorporation into the nanoparticles and films, opening a new field for the application of these materials.

  19. A Simple and Sensitive Method to Quantify Biodegradable Nanoparticle Biodistribution using Europium Chelates.

    Science.gov (United States)

    Crawford, Lindsey; Higgins, Jaclyn; Putnam, David

    2015-09-08

    The biodistribution of biodegradable nanoparticles can be difficult to quantify. We report a method using time resolved fluorescence (TRF) from a lanthanide chelate to minimize background autofluorescence and maximize the signal to noise ratio to detect biodegradable nanoparticle distribution in mice. Specifically, antenna chelates containing europium were entrapped within nanoparticles composed of polylactic acid-polyethylene glycol diblock copolymers. Tissue accumulation of nanoparticles following intravenous injection was quantified in mice. The TRF of the nanoparticles was found to diminish as a second order function in the presence of serum and tissue compositions interfered with the europium signal. Both phenomena were corrected by linearization of the signal function and calculation of tissue-specific interference, respectively. Overall, the method is simple and robust with a detection limit five times greater than standard fluorescent probes.

  20. A Comprehensive Strategy to Boost the Quantum Yield of Luminescence of Europium Complexes

    Science.gov (United States)

    Lima, Nathalia B. D.; Gonçalves, Simone M. C.; Júnior, Severino A.; Simas, Alfredo M.

    2013-01-01

    Lanthanide luminescence has many important applications in anion sensing, protein recognition, nanosized phosphorescent devices, optoelectronic devices, immunoassays, etc. Luminescent europium complexes, in particular, act as light conversion molecular devices by absorbing ultraviolet (UV) light and by emitting light in the red visible spectral region. The quantum yield of luminescence is defined as the ratio of the number of photons emitted over the number of UV photons absorbed. The higher the quantum yield of luminescence, the higher the sensitivity of the application. Here we advance a conjecture that allows the design of europium complexes with higher values of quantum yields by simply increasing the diversity of good ligands coordinated to the lanthanide ion. Indeed, for the studied cases, the percent boost obtained on the quantum yield proved to be strong: of up to 81%, accompanied by faster radiative rate constants, since the emission becomes less forbidden. PMID:23928866

  1. Assembly of europium organic framework–gold nanoparticle composite thin films on silicon substrate

    Energy Technology Data Exchange (ETDEWEB)

    Deep, Akash, E-mail: dr.akashdeep@gmail.com [Central Scientific Instruments Organisation (CSIR-CSIO), Sector 30 C, Chandigarh 160030 (India); Academy of Scientific and Innovative Research, CSIR-CSIO, Sector 30 C, Chandigarh 160030 (India); Kaur, Rajnish [Central Scientific Instruments Organisation (CSIR-CSIO), Sector 30 C, Chandigarh 160030 (India); Academy of Scientific and Innovative Research, CSIR-CSIO, Sector 30 C, Chandigarh 160030 (India); Kumar, Parveen [Central Scientific Instruments Organisation (CSIR-CSIO), Sector 30 C, Chandigarh 160030 (India); Kumar, Pawan; Paul, A.K. [Central Scientific Instruments Organisation (CSIR-CSIO), Sector 30 C, Chandigarh 160030 (India); Academy of Scientific and Innovative Research, CSIR-CSIO, Sector 30 C, Chandigarh 160030 (India)

    2014-08-28

    Metal organic frameworks are a sub-class of coordination polymers and rapidly generating huge research interests in several technological areas. One of the emerging areas of their potential applications is the photovoltaics. The present study proposes the assembly of europium organic framework–gold nanoparticle nanocomposite thin film on silicon substrate. Microscopic, X-ray diffraction, surface area measurement and thermal studies have indicated the formation of the desired thin film. Spectral studies have been used to highlight their solid state optical property. Current–voltage studies have established semiconducting property of the above thin films. - Highlights: • Thin film of europium organic framework/gold nanoparticles is prepared on silicon. • Fairly homogeneous films with a roughness factor of 5–10 nm are obtained. • Above thin films offer solid-state photoluminescence and semiconducting properties.

  2. Synthesis and optical features of an europium organic-inorganic silicate hybrid

    Energy Technology Data Exchange (ETDEWEB)

    Franville, A.C.; Zambon, D.; Mahiou, R.; Chou, S.; Cousseins, J.C. [Universite Blaise Pascal, Aubiere (France). Lab. des Materiaux Inorganiques; Troin, Y. [Laboratoire de Chimie des Heterocycles et des Glucides, EA 987, Universite Blaise-Pascal and ENSCCF, F-63177 Aubiere Cedex (France)

    1998-07-24

    A europium organic-inorganic silicate hybrid was synthesized by grafting a coordinative group (dipicolinic acid) to a silicate network precursor (3-aminopropyltriethoxysilane) via a covalent bonding. Sol-gel process and complexation were performed using different experimental conditions. The hybrid materials, in particular the Eu{sup 3+} coordination mode, were characterized by infrared and luminescence spectroscopies. Morphology of the materials and TG analysis showed that grafted silica enhanced thermal and mechanical resistances of the organic part. (orig.) 7 refs.

  3. Development of a microchip Europium nanoparticle immunoassay for sensitive point-of-care HIV detection.

    Science.gov (United States)

    Liu, Jikun; Du, Bingchen; Zhang, Panhe; Haleyurgirisetty, Mohan; Zhao, Jiangqin; Ragupathy, Viswanath; Lee, Sherwin; DeVoe, Don L; Hewlett, Indira K

    2014-11-15

    Rapid, sensitive and specific diagnostic assays play an indispensable role in determination of HIV infection stages and evaluation of efficacy of antiretroviral therapy. Recently, our laboratory developed a sensitive Europium nanoparticle-based microtiter-plate immunoassay capable of detecting target analytes at subpicogram per milliliter levels without the use of catalytic enzymes and signal amplification processes. Encouraged by its sensitivity and simplicity, we continued to miniaturize this assay to a microchip platform for the purpose of converting the benchtop assay technique to a point-of-care test. It was found that detection capability of the microchip platform could be readily improved using Europium nanoparticle probes. We were able to routinely detect 5 pg/mL (4.6 attomoles) of HIV-1 p24 antigen at a signal-to-blank ratio of 1.5, a sensitivity level reasonably close to that of microtiter-plate Europium nanoparticle assay. Meanwhile, use of the microchip platform effectively reduced sample/reagent consumption 4.5 fold and shortened total assay time 2 fold in comparison with microtiter plate assays. Complex matrix substance in plasma negatively affected the microchip assays and the effects could be minimized by diluting the samples before loading. With further improvements in sensitivity, reproducibility, usability, assay process simplification, and incorporation of portable time-resolved fluorescence reader, Europium nanoparticle immunoassay technology could be adapted to meet the challenges of point-of-care diagnosis of HIV or other health-threatening pathogens at bedside or in resource-limited settings. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Green Luminescence of Divalent Europium in the Hydride Chloride EuHCl

    NARCIS (Netherlands)

    Kunkel, Nathalie; Rudolph, Daniel; Meijerink, A; Rommel, Stefan; Weihrich, Richard; Kohlmann, Holger; Schleid, Thomas

    Luminescence properties of divalent europium in the mixed-anion hydride chloride EuHCl were studied for the first time. Olive-green single crystals of EuHCl (PbFCl-type structure: tetragonal, P4/nmm, a = 406.58(3) pm, c = 693.12(5) pm, c/a = 1.705, Z = 2) resulted from the reaction of elemental

  5. Ferromagnetic semiconductor-metal transition in heterostructures of electron doped europium monoxide

    Energy Technology Data Exchange (ETDEWEB)

    Stollenwerk, Tobias

    2013-09-15

    In the present work, we develop and solve a self-consistent theory for the description of the simultaneous ferromagnetic semiconductor-metal transition in electron doped Europium monoxide. We investigate two different types of electron doping, Gadolinium impurities and Oxygen vacancies. Besides the conduction band occupation, we can identify low lying spin fluctuations on magnetic impurities as the driving force behind the doping induced enhancement of the Curie temperature. Moreover, we predict the signatures of these magnetic impurities in the spectra of scanning tunneling microscope experiments. By extending the theory to allow for inhomogeneities in one spatial direction, we are able to investigate thin films and heterostructures of Gadolinium doped Europium monoxide. Here, we are able to reproduce the experimentally observed decrease of the Curie temperature with the film thickness. This behavior is attributed to missing coupling partners of the localized 4f moments as well as to an electron depletion at the surface which leads to a reduction of the number of itinerant electrons. By investigating the influence of a metallic substrate onto the phase transition in Gadolinium doped Europium monoxide, we find that the Curie temperature can be increased up to 20%. However, as we show, the underlying mechanism of metal-interface induced charge carrier accumulation is inextricably connected to a suppression of the semiconductor-metal transition.

  6. Redox electrochemistry of europium fluoride complexes in an equimolar NaCl-KCl melt

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, S.A., E-mail: kuznet@chemy.kolasc.net.ru [Institute of Chemistry, Kola Science Centre RAS, 26 Akademgorodok., 184209 Apatity, Murmansk region (Russian Federation); Gaune-Escard, M. [Ecole Polytechnique, Mecanique Energetique, Technopole de Chateau Gombert, 5 rue Enrico Fermi, 13453 Marseille Cedex 13 (France)

    2011-07-15

    The electrochemical behavior of europium fluoride complexes was studied by different electrochemical methods at a glassy carbon electrode in the temperature range 973-1100 K in the NaCl-KCl melt. The diffusion coefficients of Eu(III) and Eu(II) were determined by linear sweep voltammetry. The standard rate constants of charge transfer for the Eu(III)/Eu(II) redox couple were found on the base cyclic voltammetry, impedance spectroscopy and chronoamperometry data. The formal standard redox potentials E{sub Eu(III)/Eu(II)}{sup *} were obtained by linear sweep and cyclic voltammetry. The electrochemical behavior of europium fluoride and europium chloride complexes in NaCl-KCl melt was compared and discussed in connection with the strength and stability of these complexes. It was shown that the formation of stronger fluoride complexes reduced values of diffusion coefficients, standard rate constants for charge transfer of the Eu(III)/Eu(II) redox couple and shifted the formal standard redox potentials to the more electronegative values.

  7. Lateral flow immunoassay using europium chelate-loaded silica nanoparticles as labels.

    Science.gov (United States)

    Xia, Xiaohu; Xu, Ye; Zhao, Xilin; Li, Qingge

    2009-01-01

    Despite their ease of use, lateral flow immunoassays (LFIAs) often suffer from poor quantitative discrimination and low analytical sensitivity. We explored the use of a novel class of europium chelate-loaded silica nanoparticles as labels to overcome these limitations. Antibodies were covalently conjugated onto europium chelate-loaded silica nanoparticles with dextran as a linker. The resulting conjugates were used as labels in LFIA for detection of hepatitis B surface antigen (HBsAg). We performed quantification with a digital camera and Adobe Photoshop software. We also used 286 clinical samples to compare the proposed method with a quantitative ELISA. A detection limit of 0.03 microg/L was achieved, which was 100 times lower than the colloidal gold-based LFIAs and lower than ELISA. A precise quantitative dose-response curve was obtained, and the linear measurement range was 0.05-3.13 microg/L, within which the CVs were 2.3%-10.4%. Regression analysis of LFIA on ELISA results gave: log (LFIA) = -0.14 log (ELISA) + 1.03 microg/L with r = 0.99 for the quantification of HBsAg in 35 positive serum samples. Complete agreement was observed for the qualitative comparison of 286 clinical samples assayed with LFIA and ELISA. Europium chelate-loaded silica nanoparticle labels have great potential to improve LFIAs, making them useful not only for simple screening applications but also for more sensitive and quantitative immunoassays.

  8. Luminescent solutions and films of new europium complexes with chelating ligands

    Science.gov (United States)

    Kharcheva, Anastasia V.; Ivanov, Alexey V.; Borisova, Nataliya E.; Kaminskaya, Tatiana P.; Patsaeva, Svetlana V.; Popov, Vladimir V.; Yuzhakov, Viktor I.

    2015-03-01

    The development of new complexes of rare earth elements (REE) with chelating organic ligands opens up the possibility of purposeful alteration in the composition and structure of the complexes, and therefore tuning their optical properties. New ligands possessing two pyridine rings in their structure were synthesized to improve coordination properties and photophysical characteristics of REE compounds. Complexes of trivalent europium with novel chelating ligands were investigated using luminescence and absorption spectroscopy, as well as atomic force microscopy. Luminescence properties of new compounds were studied both for solutions and films deposited on the solid support. All complexes exhibit the characteristic red luminescence of Eu (III) ion with the absolute lumenescence quantum yield in polar acetonitrile solution varying from 0.21 to 1.45 % and emission lifetime ranged from 0.1 to 1 ms. Excitation spectra of Eu coordination complexes correspond with absorption bands of chelating ligand. The energy levels of the triplet state of the new ligands were determined from the phosphorescence at 77 K of the corresponding Gd (III) complexes. The morphology of films of europium complexes with different substituents in the organic ligands was investigated by atomic force microscopy (AFM). It strongly depends both on the type of substituent in the organic ligand, and the rotation speed of the spin-coater. New europium complexes with chelating ligands containing additional pyridine fragments represent outstanding candidates for phosphors with improved luminescence properties.

  9. Use of europium ions for SAD phasing of lysozyme at the Cu Kα wavelength.

    Science.gov (United States)

    Vijayakumar, Balakrishnan; Velmurugan, Devadasan

    2013-01-01

    Europium is shown to be a good anomalous scatterer in SAD phasing for solving the structure of biological macromolecules. The large value of the anomalous contribution of europium, f'' = 11.17 e(-), at the Cu Kα wavelength is an advantage in de novo phasing and automated model building. Tetragonal crystals of hen egg-white lysozyme (HEWL) incorporating europium(III) chloride (50 mM) were obtained which diffracted to a resolution of 2.3 Å at a wavelength of 1.54 Å (Cu Kα). The master data set (360° frames) was split and analyzed for anomalous signal-to-noise ratio, multiplicity, completeness, SAD phasing and automated building. The structure solution and model building of the split data sets were carried out using phenix.autosol and phenix.autobuild. The contributions of the Eu ions to SAD phasing using in-house data collection are discussed. This study revealed successful lysozyme phasing by SAD using laboratory-source data involving Eu ions, which are mainly coordinated by the side chains of Asn46, Asp52 and Asp101 together with some water molecules.

  10. Hydrothermal treatment for preparation of europium-lanthanum phosphates and exploration of their fluorescence properties

    Directory of Open Access Journals (Sweden)

    Hiroaki Onoda

    2014-04-01

    Full Text Available Europium-substituted lanthanum phosphates (Eu; 5 mol% were prepared from lanthanum nitrate, europium nitrate, and sodium polyphosphate solutions by a hydrothermal process at 120 and 160 °C up to 8 h. The obtained phosphates were studied using XRD, IR spectroscopy, TG–DTA, and SEM. UV–vis absorbance and reflectance, as well as fluorescence, were estimated as functional properties of these phosphate materials. We found that samples prepared without hydrothermal treatment were amorphous (as indicated by their XRD patterns, whereas those prepared by a hydrothermal treatment contained peaks corresponding to lanthanum orthophosphate, indicating that the hydrothermal process caused the polyphosphate(s to decompose into orthophosphate(s. The TG–DTA curves of the samples prepared by a hydrothermal treatment were different from those of the samples prepared without hydrothermal treatment. All samples reported herein had no specified shape despite using prolonged hydrothermal treatment times. Although the samples prepared without hydrothermal treatment showed only weak fluorescence peaks, those prepared by a hydrothermal treatment showed strong peaks at 556, 590, 615, and 690 nm. These peaks corresponded to transitions from 5D0 to 7F0, 7F1, 7F2, and 7F4, respectively. Collectively, these results indicate that the hydrothermal treatment is a useful method of obtaining europium-substituted lanthanum phosphates with fluorescence properties.

  11. Fabrication of coated graphite electrode for the selective determination of europium (III) ions.

    Science.gov (United States)

    Upadhyay, Anjali; Singh, Ashok Kumar; Bandi, Koteswara Rao; Jain, A K

    2013-10-15

    Preliminary complexation study showed that two ligands (ionophores) (2-((2-phenyl-2-(pyridin-2-yl)hydazono)methyl)pyridine) [L1], (2-((2-phenyl-2-(pyridin-2-yl)hydazono) methyl)phenol) [L2] can act as europium selective electrode. Europium selective coated graphite electrodes (CGE) were prepared by using ligands [L1] and [L2] and their potentiometric characteristics were determined. Membranes having different compositions of poly(vinylchloride) (PVC), the different plasticizers, anionic additives and ionophores were coated onto the graphite surface. The potential response measurements showed that the best performance was exhibited by the proposed CGE. This electrode had the widest working concentration range, Nernstian slope and fast response times of 10s. The selectivity studies showed that this electrode have higher selectivity towards Eu(3+) over a large number of cations. Furthermore, the electrode generated constant potentials in the pH range 2.7-9.0. This electrode can be used to quantify europium in soil, binary mixtures and also used as an indicator electrode in the potentiometric titration of Eu(3+) with EDTA. The proposed electrode was also successfully applied to the determination of fluoride ions in real samples. © 2013 Elsevier B.V. All rights reserved.

  12. Fluorescent Sulfur-Tagged Europium(III) Coordination Polymers for Monitoring Reactive Oxygen Species.

    Science.gov (United States)

    Wang, Huai-Song; Bao, Wen-Jing; Ren, Shi-Bin; Chen, Ming; Wang, Kang; Xia, Xing-Hua

    2015-07-07

    Oxidative stress caused by reactive oxygen species (ROS) is harmful to biological systems and implicated in various diseases. A variety of selective fluorescent probes have been developed for detecting ROS to uncover their biological functions. Generally, the preparation of the fluorescent probes usually undergoes multiple synthetic steps, and the successful fluorescent sensing usually relies on trial-and-error tests. Herein we present a simple way to prepare fluorescent ROS probes that can be used both in biological and environmental systems. The fluorescent europium(III) coordination polymers (CPs) are prepared by simply mixing the precursors [2,2'-thiodiacetic acid and Eu(NO3)3·6H2O] in ethanol. Interestingly, with the increase of reaction temperature, the product undergoes a morphological transformation from microcrystal to nanoparticle while the structure and fluorescent properties retain. The fluorescence of the sulfur-tagged europium(III) CPs can be selectively quenched by ROS, and thus, sensitive and selective monitoring of ROS in aerosols by the microcrystals and in live cells by the nanoparticles has been achieved. The results reveal that the sulfur-tagged europium(III) CPs provide a novel sensor for imaging ROS in biological and environmental systems.

  13. Facile Synthesis, Characterization, and Cytotoxic Activity of Europium-Doped Nanohydroxyapatite

    Science.gov (United States)

    Niño-Martínez, Nereyda; Patiño-Marín, Nuria

    2016-01-01

    The objective of this study was to synthetize europium-doped nanohydroxyapatite using a simple aqueous precipitation method and, thereafter, characterize and impregnate selected samples with 5-fluorouracil in order to explore the properties and the releasing capacity of this material. The nanohydroxyapatite was doped with 3, 5, 10, and 20 wt% of europium. The obtained samples were characterized after they were dried at 80°C and hydrothermal treated at 120°C by 2 hours. The samples were analyzed by transmission electron microscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy, and photoluminescence. Also, impregnation and release of 5-fluorouracil were assessed in PBS. The toxicity effects of all samples were studied using viability assays on human fibroblasts cells (HGF-1) in vitro. The sizes of the crystallites were about 10–70 nm with irregular morphology and present the phase corresponding to the JCPDS card 9–0432 for hydroxyapatite. The results of the toxicity experiments indicated that doped and undoped powders are biocompatible with fibroblasts cells. Hydroxyapatite samples doped with 5% of europium and loaded with 5-fluorouracil release almost 7 mg/L of the drug after 60 minutes in PBS and decrease the viability of HeLa cells after 24 hours. PMID:27965525

  14. Real-time in situ monitoring via europium emission of the photo-release of antitumor cisplatin from a Eu-Pt complex.

    Science.gov (United States)

    Li, Hongguang; Lan, Rongfeng; Chan, Chi-Fai; Jiang, Lijun; Dai, Lixiong; Kwong, Daniel W J; Lam, Michael Hon-Wah; Wong, Ka-Leung

    2015-09-25

    A water-soluble light-responsive antitumor agent, PtEuL, based on a cisplatin-linked europium-cyclen complex has been synthesized and evaluated for controlled cisplatin release by linear/two-photon excitation in vitro with concomitant turn-on and long-lived europium emission as a responsive traceable signal.

  15. Europium doping induced symmetry deviation and its impact on the second harmonic generation of doped ZnO nanowires

    Science.gov (United States)

    Dhara, Soumen; Imakita, Kenji; Mizuhata, Minoru; Fujii, Minoru

    2014-06-01

    In this work, we investigated the effects of europium doping on the second harmonic generation (SHG) of ZnO nanowires (NWs). A non-monotonic enhancement in the SHG is observed with the increase of the europium concentration. Maximum SHG is observed from the 1 at.% europium doped ZnO NWs with an enhancement factor of 4.5. To understand the underlying mechanism, the effective second order non-linear coefficient (deff) is calculated from the theoretical fitting with consideration of the absorption effect. Microstructural characterization reveals the structural deformation of the ZnO NWs caused by europium doping. We estimated the deviation in the crystal site symmetry around the Eu3+ ions (defined as the asymmetric factor) from photoluminescence measurement and it is found to be strongly correlated with the calculated deff value. A strong linear dependence between the magnitudes of deff and the asymmetric factor suggests that deviation in the local site symmetry of the ZnO crystal by europium doping could be the most probable origin of the observed large second order non-linearity.

  16. Antimalarial Activity of KAF156 in Falciparum and Vivax Malaria.

    Science.gov (United States)

    White, Nicholas J; Duong, Tran T; Uthaisin, Chirapong; Nosten, François; Phyo, Aung P; Hanboonkunupakarn, Borimas; Pukrittayakamee, Sasithon; Jittamala, Podjanee; Chuthasmit, Kittiphum; Cheung, Ming S; Feng, Yiyan; Li, Ruobing; Magnusson, Baldur; Sultan, Marc; Wieser, Daniela; Xun, Xiaolei; Zhao, Rong; Diagana, Thierry T; Pertel, Peter; Leong, F Joel

    2016-09-22

    KAF156 belongs to a new class of antimalarial agents (imidazolopiperazines), with activity against asexual and sexual blood stages and the preerythrocytic liver stages of malarial parasites. We conducted a phase 2, open-label, two-part study at five centers in Thailand and Vietnam to assess the antimalarial efficacy, safety, and pharmacokinetic profile of KAF156 in adults with acute Plasmodium vivax or P. falciparum malaria. Assessment of parasite clearance rates in cohorts of patients with vivax or falciparum malaria who were treated with multiple doses (400 mg once daily for 3 days) was followed by assessment of the cure rate at 28 days in a separate cohort of patients with falciparum malaria who received a single dose (800 mg). Median parasite clearance times were 45 hours (interquartile range, 42 to 48) in 10 patients with falciparum malaria and 24 hours (interquartile range, 20 to 30) in 10 patients with vivax malaria after treatment with the multiple-dose regimen and 49 hours (interquartile range, 42 to 54) in 21 patients with falciparum malaria after treatment with the single dose. Among the 21 patients who received the single dose and were followed for 28 days, 1 had reinfection and 7 had recrudescent infections (cure rate, 67%; 95% credible interval, 46 to 84). The mean (±SD) KAF156 terminal elimination half-life was 44.1±8.9 hours. There were no serious adverse events in this small study. The most common adverse events included sinus bradycardia, thrombocytopenia, hypokalemia, anemia, and hyperbilirubinemia. Vomiting of grade 2 or higher occurred in 2 patients, 1 of whom discontinued treatment because of repeated vomiting after receiving the single 800-mg dose. More adverse events were reported in the single-dose cohort, which had longer follow-up, than in the multiple-dose cohorts. KAF156 showed antimalarial activity without evident safety concerns in a small number of adults with uncomplicated P. vivax or P. falciparum malaria. (Funded by Novartis and

  17. Photon Strength Functions for ^156, 157, 159Gd

    Science.gov (United States)

    Baramsai, Bayarbadrakh; Mitchell, G. E.; Chyzh, A.; Dashdorj, D.; Walker, C.; Bredeweg, T. A.; Couture, A.; Haight, R. C.; Jandel, M.; Keksis, A. L.; O'Donnell, J. M.; Rundberg, R. S.; Wouters, J. M.; Ullmann, J. L.; Vieira, D. J.; Agvaanluvsan, U.; Becvar, F.; Krticka, M.

    2010-11-01

    In recent years the low energy behavior of the Photon Strength Function (PSF) has attracted much attention. A completely consistent description of this behavior is not available. The neutron capture γ-ray spectra measured by the DANCE detector array located at the Los Alamos Neutron Science Center has been used for the study of the PSF below the neutron separation energy. The radiative decay of the compound nuclei ^156, 157, 159Gd has been measured. The spectra were simulated with the DICEBOX code. A variety of phenomenological models of the PSF were considered in the simulations. Comparison of the experimental and simulated spectra will be presented.

  18. 26 CFR 156.5881-1 - Imposition of excise tax on greenmail.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Imposition of excise tax on greenmail. 156.5881-1 Section 156.5881-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES (CONTINUED) EXCISE TAX ON GREENMAIL Tax on Greenmail § 156.5881-1 Imposition of excise tax on greenmail. (a) In genera...

  19. 27 CFR 25.156 - Determination of tax on keg beer.

    Science.gov (United States)

    2010-04-01

    ... keg beer. 25.156 Section 25.156 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Tax on Beer Determination of Tax § 25.156 Determination of tax on keg beer. (a) In determining the tax on beer removed in kegs, a barrel is regarded as a...

  20. 9 CFR 381.156 - Poultry meat content standards for certain poultry products.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Poultry meat content standards for certain poultry products. 381.156 Section 381.156 Animals and Animal Products FOOD SAFETY AND INSPECTION... Definitions and Standards of Identity or Composition § 381.156 Poultry meat content standards for certain...

  1. 33 CFR 110.156 - Randall Bay, Freeport, Long Island, N.Y.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Randall Bay, Freeport, Long Island, N.Y. 110.156 Section 110.156 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.156 Randall Bay, Freeport, Long Island, N...

  2. 10 CFR 431.156 - Energy and water conservation standards and effective dates.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Energy and water conservation standards and effective dates. 431.156 Section 431.156 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM... Standards § 431.156 Energy and water conservation standards and effective dates. Each commercial clothes...

  3. Charge growth, dispersion in europium manganite (EuMnO{sub 3-{delta}}) ceramics revealed using opto-impedance probe

    Energy Technology Data Exchange (ETDEWEB)

    Radhakrishnan, S. [Central Electrochemical Research Institute, Karaikudi-630006, T.N. (India); Jagannathan, R., E-mail: jags57_99@yahoo.com [Central Electrochemical Research Institute, Karaikudi-630006, T.N. (India)

    2011-05-19

    Highlights: > In this study, using opto-, magneto-opto impedance techniques, experimental proof for charge growth in europium manganite (EuMnO{sub 3}) near the region of its Neel temperature is presented. > This study gives data related to dielectric properties of europium manganite. > This study may open-up new avenues for investigating the dielectric characteristics of many electronic-ceramics. - Abstract: In this preliminary report, we present the impedance characteristics of poly-crystalline europium manganite, a promising colossal magneto resistance (CMR) system investigated under optical ({approx}5 eV) and magnetic (0.1 T) perturbations yielding some clues on the charge build-up and dispersion processes. This may possibly be resulting from switching between ferromagnetic and anti-ferromagnetic phases through a charge transfer transition mediated process centering Mn{sup 3+/4+} 3d spins thereby meriting a more detailed study correlating with magnetic measurements.

  4. Rapid and accurate tumor-target bio-imaging through specific in vivo biosynthesis of a fluorescent europium complex.

    Science.gov (United States)

    Ye, Jing; Wang, Jianling; Li, Qiwei; Dong, Xiawei; Ge, Wei; Chen, Yun; Jiang, Xuerui; Liu, Hongde; Jiang, Hui; Wang, Xuemei

    2016-04-01

    A new and facile method for rapidly and accurately achieving tumor targeting fluorescent images has been explored using a specifically biosynthesized europium (Eu) complex in vivo and in vitro. It demonstrated that a fluorescent Eu complex could be bio-synthesized through a spontaneous molecular process in cancerous cells and tumors, but not prepared in normal cells and tissues. In addition, the proteomics analyses show that some biological pathways of metabolism, especially for NADPH production and glutamine metabolism, are remarkably affected during the relevant biosynthesis process, where molecular precursors of europium ions are reduced to fluorescent europium complexes inside cancerous cells or tumor tissues. These results proved that the specific self-biosynthesis of a fluorescent Eu complex by cancer cells or tumor tissues can provide a new strategy for accurate diagnosis and treatment strategies in the early stages of cancers and thus is beneficial for realizing precise surgical intervention based on the relevant cheap and readily available agents.

  5. Polystyrene latex particles containing europium complexes prepared by miniemulsion polymerization using bovine serum albumin as a surfactant for biochemical diagnosis.

    Science.gov (United States)

    Aikawa, Tatsuo; Mizuno, Akihiro; Kohri, Michinari; Taniguchi, Tatsuo; Kishikawa, Keiki; Nakahira, Takayuki

    2016-09-01

    Luminescent particles have been attracting significant attention because they can be used in biochemical applications, such as detecting and imaging biomolecules. In this study, luminescent polystyrene latex particles were prepared through miniemulsion polymerization of styrene with dissolved europium complexes in the presence of bovine serum albumin (BSA) and poly(ethylene glycol) monomethoxy methacrylate as surfactants. The solubility of the europium complex in styrene has a strong effect on the yield of the particle. Europium tris(2-thenoyl trifluoroacetonate) di(tri-n-octyl phosphine oxide), which has a high solubility in styrene, was sufficiently incorporated into the polystyrene particles compared to europium tris(2-thenoyl trifluoroacetonate), which has a low solubility in styrene. The luminescence property of the europium complex could remain intact even after its incorporation through the miniemulsion polymerization. In the aqueous dispersion, the resulting particles could emit strong luminescence, which is a characteristic of the europium complex. The antibody fragments were covalently attached to BSA-covered particles after a reaction with a bifunctional linker, N-(6-maleimidocaproyloxy)succinimide. The time-resolved fluoroimmunoassay technique showed that 3.3pg/mL of human α-fetoproteins (AFP) can be detected by using the resulting luminescent particles. An immunochromatographic assay using the resulting particles was also performed as a convenient method to qualitatively detect biomolecules. The detection limit of AFP measured by the immunochromatographic assay was determined to be 2000pg/mL. These results revealed that the luminescent particles obtained in this study can be utilized for the highly sensitive detection of biomolecules and in vitro biochemical diagnosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Highly specific ''sensing'' of tryptophan by a luminescent europium(III) complex

    Energy Technology Data Exchange (ETDEWEB)

    Stubenrauch, Jan A.; Mevissen, Christian; Schulte, Marie F.; Bochenek, Steffen; Albrecht, Markus [RWTH Univ. Aachen (Germany). Inst. fuer Organische Chemie; Subramanian, Palani S. [Central Salt and Marine Chemicals, Research Institute (CSRI), Gujarat (India)

    2016-07-01

    The europium(III) complex 1-Cl{sub 3} (S,S-2,2{sup '}-(((1,10-phenanthroline-2,9-diyl)bis(methanylylidene))bis (azanylyliden e))bis(3-methylbutanamide)europiumtrichloride) undergoes, only in the presence of the amino acid tryptophan, a change of emission at 615 nm. In the presence of few equivalents of tryptophan, emission of the europium complex is enhanced while it disappears upon addition of large amounts. This behavior can be assigned to displacement of the sensitizing phenanthroline ligand of 1-Cl{sub 2} x Trp in the latter case.

  7. Electron-induced desorption of europium atoms from oxidized tungsten surface: concentration dependence of low-energy peak

    CERN Document Server

    Davydov, S Y

    2002-01-01

    One discusses nature of electron induced desorption of Eu sup 0 europium atoms under E sub e irradiating electron low-energies (approx 30 eV) and peculiarities of yield dependence of Eu sup 0 atoms on their concentration at oxidized tungsten surface. Primary act of vacancy origination in europium adatom inner 5p-shell turned to be the determining stage. Evaluations have shown that just the first of two possible scenarios of ionization (electron intra-atomic to Eu adatom external quasi-level or realise of knocked out electron into vacuum) leads to Eu sup 0 desorption. One determined concentration threshold for yield of Eu sup 0 atoms

  8. Optical properties of europium(III) {beta}-diketonate/polymer-doped systems using supercritical carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Gerasimova, V.I., E-mail: vis@srd.sinp.msu.ru [Skobel' tsyn Research Institute of Nuclear Physics, Moscow State University, Leninskie Gory 1-2, GSP-1, 119991 Moscow (Russian Federation); Antoshkov, A.A.; Zavorotny, Yu.S.; Rybaltovskii, A.O. [Skobel' tsyn Research Institute of Nuclear Physics, Moscow State University, Leninskie Gory 1-2, GSP-1, 119991 Moscow (Russian Federation); Lemenovskii, D.A., E-mail: dali@org.chem.msu.ru [Chemistry Department, Moscow State University, Leninskie Gory 1-3, GSP-1, 119991 Moscow (Russian Federation)

    2013-02-15

    The optical properties of fluoropolymers and polypropylene doped with europium(III) {beta}-diketonates Eu(L){sub 3}{center_dot}2H{sub 2}O and Eu(L){sub 3}phen (L: fod=6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato, bta=4,4,4-trifluoro-1-phenyl-1,3-butanedione, tta=4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione, and phen=1,10-phenanthroline) using supercritical carbon dioxide were investigated by absorption and emission spectra. A comparative analysis of the PL decay times of Eu{sup 3+} ions in the initial europium (III) {beta}-diketonates and impregnated fluoropolymers was carried out. The supercritical fluid (SCF) impregnation of polymer samples with europium(III) {beta}-diketonates containing 1,10-phenanthroline was found to be obstructed differently depending on the type of ligand in the entire investigated impregnation temperature range (T{sub SCF}=50-90 Degree-Sign S). It is shown that from the variety of Eu(L){sub 3}phen only Eu(fod){sub 3}phen can be introduced into the polymer matrix by this method. - Highlights: Black-Right-Pointing-Pointer The optical properties of polymers doped with Eu{sup 3+} {beta}-diketonates using SC CO{sub 2} were investigated. Black-Right-Pointing-Pointer A comparative analysis of the PL decay times in the initial Eu{sup 3+} {beta}-diketonates and doped polymers was carried out. Black-Right-Pointing-Pointer The SC CO{sub 2} impregnation of polymers with Eu{sup 3+} {beta}-diketonates containing 1,10-phenanthroline was found to be obstructed.

  9. Reverse lyotropic liquid crystals from europium nitrate and P123 with enhanced luminescence efficiency.

    Science.gov (United States)

    Yi, Sijing; Li, Qintang; Liu, Hongguo; Chen, Xiao

    2014-10-02

    Fabrication of lyotropic aggregates containing the lanthanide ions is becoming a preferable way to prepare novel functional materials. Here, the lyotropic liquid crystals (LLCs) of reverse hexagonal, reverse bicontinuous cubic, and lamellar phases have been constructed in sequence directly from the mixtures of Eu(NO3)3·6H2O and Pluronic P123 amphiphilc block copolymer with increasing the salt proportion. Their phase types and structural characteristics were analyzed using polarized optical microscopy (POM) and small-angle X-ray scattering (SAXS) measurements. The driving forces of reverse LLC phase formation were investigated using Fourier-transformed infrared spectroscopy (FTIR) and rheological measurements. The hydrated europium salt was found to act not only as a solvent here, but also as the bridge to form hydrogen bonding between coordinated water molecules and PEO blocks, which played a key role in the reverse LLCs formation. Compared to those in aqueous solutions and solid state, the enhanced luminescence quantum yields and prolonged excited state lifetimes were observed in two europium containing reverse mesophases. The luminescence quenching effect of lanthanide ions was efficiently suppressed, probably due to the substitution of coordinated water molecules by oxyethyl groups of P123 and ordered phase structures of LLCs, where the coordinated europium ions were confined and isolated by PEO blocks. The optimum luminescence performance was then found to exist in the reverse hexagonal phase. The obtained results on such lanthanide-induced reverse LLCs should be referable for designing new luminescent soft materials construction to expand their application fields.

  10. How Do Radionuclides Accumulate in Marine Organisms? A Case Study of Europium with Aplysina cavernicola.

    Science.gov (United States)

    Maloubier, Melody; Shuh, David K; Minasian, Stefan G; Pacold, Joseph I; Solari, Pier-Lorenzo; Michel, Hervé; Oberhaensli, François R; Bottein, Yasmine; Monfort, Marguerite; Moulin, Christophe; Den Auwer, Christophe

    2016-10-04

    In the ocean, complex interactions between natural and anthropogenic radionuclides, seawater, and diverse marine biota provide a unique window through which to examine ecosystem and trophic transfer mechanisms in cases of accidental dissemination. The nature of interaction between radionuclides, the marine environment, and marine species is therefore essential for better understanding transfer mechanisms from the hydrosphere to the biosphere. Although data pertaining to the rate of global transfer are often available, little is known regarding the mechanism of environmental transport and uptake of heavy radionuclides by marine species. Among marine species, sponges are immobile active filter feeders and have been identified as hyperaccumulators of several heavy metals. We have selected the Mediterranean sponge Aplysina cavernicola as a model species for this study. Actinide elements are not the only source of radioactive release in cases of civilian nuclear events; however, their physicochemical transfer mechanisms to marine species remain largely unknown. We have targeted europium(III) as a representative of the trivalent actinides such as americium or curium. To unravel biological uptake mechanisms of europium in A. cavernicola, we have combined radiometric (γ) measurements with spectroscopic (time-resolved laser-induced fluorescence spectroscopy, TRLIFS, and X-ray absorption near-edge structure, XANES) and imaging (transmission electron microscopy, TEM, and scanning transmission X-ray microscopy, STXM) techniques. We have observed that the colloids of NaEu(CO3)2·nH2O formed in seawater are taken up by A. cavernicola with no evidence that lethal dose has been reached in our working conditions. Spectroscopic results suggest that there is no change of speciation during uptake. Finally, TEM and STXM images recorded at different locations across a sponge cross section, together with differential cell separation, indicate the presence of europium particles (around

  11. Trace electrochemical analysis of Europium, Ytterbium, and Cerium at their joint presence in solution

    Directory of Open Access Journals (Sweden)

    Rema Matakova

    2012-03-01

    Full Text Available In the course of several decades at the department of analytical chemistry and chemistry of rare elements there were studied the electrode processes with participation of rare-earth metals (REM in accordance with the long awaiting problem of the development of rare-metal and rare-earth branch of non-ferrous metallurgy of Kazakhstan. With the aim of express and highly sensitive analytical control of raw materials and final product of rare-earth industry there were developed the methods of inversion-voltamperometric determination of low concentrations of europium, ytterbium and cerium under the conditions of their individual and combined presence in the solution.

  12. Synergistic extraction of europium and americium into nitrobenzene by using hydrogen dicarbollylcobaltate and dodecaethylene glycol.

    Science.gov (United States)

    Makrlík, Emanuel; Vaňura, Petr; Selucký, Pavel

    2013-01-01

    Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of dodecaethylene glycol (DDEG, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, H2L2+, ML3+ and MH-1L2+ (M3+ = Eu3+, Am3+; L = DDEG) are extracted into the organic phase. The values of extraction and stability constants of the complex species in nitrobenzene saturated with water have been determined. It was found that in this nitrobenzene medium, the stability constant of the EuL3+ complex is comparable with that of AmL3+.

  13. Red/blue electroluminescence from europium-doped organic light emitting diodes

    Science.gov (United States)

    Hagen, Joshua A.; Li, Wayne X.; Grote, James G.; Steckl, Andrew J.

    2006-02-01

    Red/Blue emitting organic light emitting diodes (OLED) devices have been obtained using a Europium-doped organic emitting layer (NPB:Eu). The Eu-doped OLEDs emit in 2 color ranges: a broad blue (~420-500nm) band due to NPB emission and a narrow red peak at 620nm due to Eu emission. The red/blue devices achieve a brightness ~13x more intense than a similarly structured green (Alq 3) emitting OLED. These NPB:Eu emitting structures also reach a maximum efficiency of 0.2 cd/A at brightnesses above 100 cd/m2.

  14. Test of zircon materials for sorption of europium; Pruebas de materiales circoniferos para sorcion de europio

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez R, E.; Fernandez V, S.M.; Garcia R, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-07-01

    In previous works it has already been made notice that some phosphates have the property of sipping radioactive metals in solution, what takes advantage to fabricate reactive barriers that are placed in the repositories of nuclear wastes. In our laboratory it has been obtained to the zirconium silicate (ZrSiO{sub 4}) and the alpha zirconium hydrogen phosphate (Zr(HPO{sub 4}) 2H{sub 2}0) starting from sea sand in an easy and economic way. With the interest of knowing if these compounds can be used in contention barriers the evaluation of their surface properties it is made and of europium sorption. (Author)

  15. Sol-Gel Synthesis, X-Ray Diffraction Studies, and Electric Conductivity of Sodium Europium Silicate

    Directory of Open Access Journals (Sweden)

    Ekaterina V. Borisova

    2013-01-01

    Full Text Available Sodium europium silicate, NaEu9(SiO46O2, with apatite structure has been obtained and studied using X-ray diffraction and SEM. It has been shown that sodium sublimation does not take place upon synthesis by the sol-gel method. Rietveld refinement has revealed that sodium atoms are ordered and occupy the 4f position. O(4 atoms not related to silicate ions are placed at the centers of Eu(2 triangles. DC and AC electric conductivity and activation energy have been determined for the compound studied.

  16. New Class of Bright and Highly Stable Chiral Cyclen Europium Complexes for Circularly Polarized Luminescence Applications.

    Science.gov (United States)

    Dai, Lixiong; Lo, Wai-Sum; Coates, Ian D; Pal, Robert; Law, Ga-Lai

    2016-09-06

    High glum values of +0.30 (ΔJ = 1, 591 nm, in DMSO) and -0.23 (ΔJ = 1, 589 nm, in H2O) were recorded in our series of newly designed macrocyclic europium(III) complexes. A sterically locking approach involving a bidentate chromophore is adopted to control the formation of one stereoisomer, giving rise to extreme rigidity, high stability, and high emission intensity. The combination of a chiral substituent on a macrocyclic chelate for lanthanide ions opens up new perspectives for the further development of circulary polarized luminescent chiral tags in optical and bioapplications.

  17. A microemulsion preparation of nanoparticles of europium in silica with luminescence enhancement using silver

    Science.gov (United States)

    Ma, Zhi Ya; Dosev, Dosi; Kennedy, Ian M

    2010-01-01

    A facile one-pot microemulsion method has been developed for the synthesis of spherical silver core–silica shell (Ag@SiO2) nanoparticles with europium chelates doped in the shell through a silane agent. The method is significantly more straightforward than other extant methods. Measurements of the luminescent emissions from the Ag@SiO2 nanoparticles, in comparison with control silica nanoparticles without silver cores, showed that the presence of the silver cores can increase the fluorescence intensity approximately 24-fold and decrease the luminescence lifetime. This enhancement offers a potential increase in overall particle detectability with increased fluorophore photostability. PMID:19417456

  18. Metal Controlled Diastereoselective Self-assembly and Circularly Polarized Luminescence of a Chiral Heptanuclear Europium Wheel

    Science.gov (United States)

    Bozoklu, Gülay; Gateau, Christelle; Imbert, Daniel; Pécaut, Jacques; Robeyns, Koen; Filinchuk, Yaroslav; Memon, Farah; Muller, Gilles

    2012-01-01

    The chiral dissymmetric tetradentate ligand SPhbipox (6’-(4-phenyloxazolin-2-yl)-2,2’-bipyridine-6-carboxylic acid) leads to the diastereoselective assembly of a homochiral Eu(III) triangle and of a highly emissive (QY=27%) heptanuclear wheel which is the largest example of chiral luminescent complex of Eu(III) reported to date. We show that the nuclearity of the assembly is controlled by the solvent and the europium cation. All the compounds show large circularly polarized luminescence with an activity which varies with the nature of the assembly (highest for the homochiral trimer). PMID:22548280

  19. A europium(III)-based PARACEST agent for sensing singlet oxygen by MRI

    Science.gov (United States)

    Song, Bo; Wu, Yunkou; Yu, Mengxiao; Zhao, Piyu; Zhou, Cheng; Kiefer, Garry E.

    2013-01-01

    A europium (III) DOTA-tetraamide complex was designed as a MRI sensor of singlet oxygen (1O2). The water soluble, thermodynamically stable complex reacts rapidly with 1O2 to form an endoperoxide derivative that results in an ∼3 ppm shift in the position of the Eu(III)-bound water chemical exchange saturation transfer (CEST) peak. The potential of using this probe to detect accumulation of the endoperoxide derivative in biological media by ratiometric CEST imaging was demonstrated. PMID:23575743

  20. MicroRNA156 improves drought stress tolerance in alfalfa (Medicago sativa) by silencing SPL13.

    Science.gov (United States)

    Arshad, Muhammad; Feyissa, Biruk A; Amyot, Lisa; Aung, Banyar; Hannoufa, Abdelali

    2017-05-01

    Alfalfa (Medicago sativa) is an important forage crop that is often grown in areas that frequently experience drought and water shortage. MicroRNA156 (miR156) is an emerging tool for improving various traits in plants. We tested the role of miR156d in drought response of alfalfa, and observed a significant improvement in drought tolerance of miR156 overexpression (miR156OE) alfalfa genotypes compared to the wild type control (WT). In addition to higher survival and reduced water loss, miR156OE genotypes also maintained higher stomatal conductance compared to WT during drought stress. Furthermore, we observed an enhanced accumulation of compatible solute (proline) and increased levels of abscisic acid (ABA) and antioxidants in miR156OE genotypes. Similarly, alfalfa plants with reduced expression of miR156-targeted SPL13 showed reduced water loss and enhanced stomatal conductance, chlorophyll content and photosynthetic assimilation. Several genes known to be involved in drought tolerance were differentially expressed in leaf and root of miR156 overexpression plants. Taken together, our findings reveal that miR156 improves drought tolerance in alfalfa at least partially by silencing SPL13. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  1. Neutron and Charged-Particle Induced Cross Sections for Radiochemistry in the Region of Samarium, Europium, and Gadolinium

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, R D; Kelley, K; Dietrich, F S; Bauer, R; Mustafa, M

    2004-11-30

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron and proton induced nuclear reaction cross sections in the mass region of samarium, europium and gadolinium (62 {le} Z {le} 64, 82 {le} N {le} 96).

  2. Colloidal europium nanoparticles via a solvated metal atom dispersion approach and their surface enhanced Raman scattering studies.

    Science.gov (United States)

    Urumese, Ancila; Jenjeti, Ramesh Naidu; Sampath, S; Jagirdar, Balaji R

    2016-08-15

    Chemistry of lanthanide metals in their zerovalent state at the nanoscale remains unexplored due to the high chemical reactivity and difficulty in synthesizing nanoparticles by conventional reduction methods. In the present study, europium(0) nanoparticles, the most reactive of all the rare earth metals have been synthesized by solvated metal atom dispersion (SMAD) method using hexadecyl amine as the capping agent. The as-prepared europium nanoparticles show surface Plasmon resonance (SPR) band in the visible region of the electromagnetic spectrum. This lead to the investigation of its surface enhanced Raman scattering (SERS) using visible light excitation source. The SERS activity of europium nanoparticles has been followed using 4-aminothiophenol and biologically important molecules such as hemoglobin and Cyt-c as the analytes. This is the first example of lanthanide metal nanoparticles as SERS substrate which can possibly be extended to other rare-earth metals. Since hemoglobin absorbs in the visible region, the use of visible light excitation source leads to surface enhanced resonance Raman spectroscopy (SERRS). The interaction of biomolecules with Eu(0) has been followed using FT-IR and UV-visible spectroscopy techniques. The results indicate that there is no major irreversible change in the structure of biomolecules upon interaction with europium nanoparticles. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Rapid screening of oxytetracycline residue in catfish muscle by dispersive liquid-liquid microextraction and europium-sensitized luminescence

    Science.gov (United States)

    Oxytetracycline (OTC) residue in catfish muscle was screened by dispersive liquid-liquid microextraction (DLLME) and europium-sensitized luminescence (ESL). After extraction in EDTA, HCl, and acetonitrile, cleanup was carried out by DLLME, and ESL was measured at microgram = 385 nm and wavelength = ...

  4. Luminescence variations in europium-doped silicon-substituted hydroxyapatite nanobiophosphor via three different methods

    Energy Technology Data Exchange (ETDEWEB)

    Thang, Cao Xuan; Pham, Vuong-Hung, E-mail: vuong.phamhung@hust.edu.vn

    2015-07-15

    Highlights: • Europium doped silicon-substituted hydroxyapatite was synthesized by wet chemical synthesis method. • Morphology of nanoparticles depended on the synthesized method. • Photoluminescence intensity of the sample increases with the increasing of Si substitutions, Eu dopants and thermal annealing. - Abstract: This paper reports the first attempt for the synthesis of europium-doped Si-substituted hydroxyapatite (HA) nanostructure to achieve strong and stable luminescence of nanobiophosphor, particularly, by addition of different Eu dopants, Si substitutions, and application of optimum annealing temperatures of up to 1000 °C. The nanobiophosphor was synthesized by the coprecipitation, microwave, and hydrothermal methods. The nanoparticles demonstrated a nanowire to a spindle-like morphology, which was dependent on the method of synthesis. The photoluminescence (PL) intensity of the sample increases with the increase in Si substitutions and Eu dopants. The luminescent nanoparticles also showed the typical luminescence of Eu{sup 3+} centered at 610 nm, which was more efficient for the annealed Eu-doped Si-HA nanoparticles than for the as-synthesized nanoparticles. Among the different synthesis methods, the hydrothermal method reveals the best light emission represented by high PL intensity and narrow PL spectra. These results suggest the potential application of Eu-doped Si-HA in stable and biocompatible nanophosphors for light emission and nanomedicine.

  5. Resonance ionization spectroscopy of Europium The first application of the PISA at ISOLDE-RILIS

    CERN Document Server

    AUTHOR|(CDS)2099873; Marsh, Bruce Alan

    The following work has been carried out at the radioactive ion beam facility ISOLDE at CERN. A compact atomic beam unit named PISA (Photo Ionization Spectroscopy Apparatus) has been implemented as a recent addition to the laboratory of the Resonance Ionization Laser Ion Source (RILIS). The scope of this thesis work was to demonstrate different applications of the PISA, using the existing and highly developed laser setup of the RILIS installation. In a demonstration of the suitability of PISA for ionization scheme development, a new ionization scheme for Europium has been developed. This resulted in the observation of several new autoionizing states and Rydberg series. Through the analysis of the observed Rydberg resonances a refined value of $45734.33(3)(3)$ cm$^{-1}$ for the ionization potential of the europium atom has been determined. In addition this thesis reports on the feasibility of the use of the PISA as a RILIS performance monitoring device during laser ion source operations. Finally the present wor...

  6. Structural and electrical properties of the europium-doped indium zinc oxide thin film transistors

    Energy Technology Data Exchange (ETDEWEB)

    Ting, Chu-Chi, E-mail: ccting@ccu.edu.tw [Graduate Institute of Opto-Mechatronics Engineering, National Chung Cheng University, 168 University Rd., Min-Hsiung, Chia-Yi, Taiwan, ROC (China); Advanced Institute for Manufacturing with High-Tech Innovations, National Chung Cheng University, 168 University Rd., Min-Hsiung, Chia-Yi, Taiwan, ROC (China); Li, Wei-Yang; Wang, Ching-Hua; Yong, Hua-En [Graduate Institute of Opto-Mechatronics Engineering, National Chung Cheng University, 168 University Rd., Min-Hsiung, Chia-Yi, Taiwan, ROC (China)

    2014-07-01

    The EuInZnO (EIZO) thin film transistor (TFT) devices were fabricated by the sol–gel spin-coating technique. The EIZO TFT operates in the n-channel depletion mode and exhibits a well-defined pinch-off and saturation region. Because europium ion possesses lower electronegativity (1.2) and standard electrode potential (− 1.991 V), it can act as the carrier suppressor to reduce the carrier concentrations of the IZO (In:Zn = 1:1) thin film. Eu{sup 3+} (13 mol%)-doped IZO TFT possesses the optimum performance, and its field-effect mobility in the saturated regime, threshold voltage, on–off ratio, and S-factor are 1.23 cm{sup 2}/Vs, 3.28 V, 1.07 × 10{sup 6}, and 2.28 V/decade, respectively. - Highlights: • Europium ions can act as the carrier suppressor in the InZnO system. • The EuInZnO forms an n-channel material for the thin film transistor (TFT) device. • The optimum performance of the EuInZnO TFT is the sample with 13 mol% Eu{sup 3+} doping.

  7. Europium phosphomolybdate and osmium metallopolymer multi-functional LbL films: redox and electrocatalytic properties.

    Science.gov (United States)

    Fernandes, Diana M; Vos, Johannes G; Freire, Cristina

    2014-04-15

    Hybrid multilayer films composed by osmium metallopolymer [Os(bpy)2(PVP)10Cl]Cl (Os-poly) and europium phosphomolybdate, K₁₁[Eu(III)(PMo₁₁O₃₉)₂] (Eu(PMo11)2), were prepared using the electrostatic layer-by-layer (LbL) self-assembly method. The film build-up, monitored by electronic spectroscopy, showed a regular stepwise growth indicating a strong interaction between layers. The XPS measurements corroborated the successful fabrication of the hybrid films with the Os-poly/Eu(PMo11)2 composition. SEM images revealed a completely covered surface with a highly roughened texture. Electrochemical characterisation of films by cyclic voltammetry revealed three Mo-based reduction processes (Mo(VI)→Mo(V)) in the potential range between -0.4 and 0.1 V and one Os reduction process (Os(III)→Os(II)) at ≈0.270 V. The cyclic voltammograms of two electroactive probes, [Fe(CN)₆](3-/4-) and [Ru(NH₃)₆](3+/2+) on {Os-poly/Eu(PMo11)2}n modified electrodes revealed redox mediation between film and the probes. Furthermore, the {Os-poly/Eu(PMo11)2}n multilayer films also showed excellent Mo-based electrocatalytic activity towards reduction of nitrite and iodate, confirming the multi-functional properties of the hybrid europium phosphomolybdate - osmium metallopolymer LbL films. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Theoretical spectroscopic study of the conjugate microcystin-LR-europium cryptate

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Julio G.; Dutra, Jose Diogo L.; Costa Junior, Nivan B. da; Freire, Ricardo O., E-mail: rfreire@ufs.br [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Quimica; Alves Junior, Severino; Sa, Gilberto F. de [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Quimica Fundamental

    2013-02-15

    In this work, theoretical tools were used to study spectroscopic properties of the conjugate microcystin-LR-europium cryptate. The Sparkle/AM1 model was applied to predict the geometry of the system and the INDO/S-CIS model was used to calculate the excited state energies. Based on the Judd-Ofelt theory, the intensity parameters were predicted and a theoretical model based on the theory of the 4f-4f transitions was applied to calculate energy transfer and backtransfer rates, radiative and non-radiative decay rates, quantum efficiency and quantum yield. A detailed study of the luminescent properties of the conjugate Microcystin-LR-europium cryptate was carried out. The results show that the theoretical quantum yield of luminescence of 23% is in good agreement with the experimental value published. This fact suggests that this theoretical protocol can be used to design new systems in order to improve their luminescence properties. The results suggest that this luminescent system may be a good conjugate for using in assay ELISA for detection by luminescence of the Microcystin-LR in water. (author)

  9. pH-controlled delivery of luminescent europium coated nanoparticles into platelets

    Science.gov (United States)

    Davies, Amy; Lewis, David J.; Watson, Stephen P.; Thomas, Steven G.; Pikramenou, Zoe

    2012-01-01

    Water soluble, luminescent gold nanoparticles are delivered into human platelets via a rapid, pH-controlled mechanism using a pH low insertion peptide, pHLIP. The approach introduces cocoating of gold nanoparticles with a europium luminescent complex, EuL and the pHLIP peptide to give pHLIP•EuL•Au. The 13-nm diameter gold nanoparticles act as a scaffold for the attachment of both the luminescent probe and the peptide to target delivery. Their size allows delivery of approximately 640 lanthanide probes per nanoparticle to be internalized in human platelets, which are not susceptible to transfection or microinjection. The internalization of pHLIP•EuL•Au in platelets, which takes just minutes, was studied with a variety of imaging modalities including luminescence, confocal reflection, and transmission electron microscopy. The results show that pHLIP•EuL•Au only enters the platelets in low pH conditions, pH 6.5, mediated by the pHLIP translocation across the membrane, and not at pH 7.4. Luminescence microscopy images of the treated platelets show clearly the red luminescence signal from the europium probe and confocal reflection microscopy confirms the presence of the gold particles. Furthermore, transmission electron microscopy gives a detailed insight of the internalization and spatial localization of the gold nanoparticles in the platelets. Thus, we demonstrate the potential of the design to translocate multimodal nanoparticle probes into cells in a pH dependent manner. PMID:22308346

  10. Analysis of metal surfaces coated with europium-doped titanium dioxide by laser induced breakdown spectroscopy.

    Science.gov (United States)

    Głogocka, Daria; Noculak, Agnieszka; Pucińska, Joanna; Jopek, Wojciech; Podbielska, Halina; Langner, Marek; Przybyło, Magdalena

    2015-01-01

    The surface passivation with titanium sol-gel coatings is a frequently used technique to control the adsorption of selected biological macromolecules and to reduce the exposure of the bulk material to biological matter. Due to the increasing number of new coating-preparation methods and new gel compositions with various types of additives, the quality and homogeneity determination of the surface covering is a critical factor affecting performance of any implanted material. While coating thickness is easy to determine, the homogeneity of the surface distribution of coating materials requires more elaborate methodologies. In the paper, the laser induced breakdown spectroscopy (LIBS) based method, capable to quantitate the homogeneity and uniformity of the europium in titanium dioxide sol-gel coatings on stainless steel surfaces prepared with two different procedures: spin-coating and dip-coating, is presented. The emission intensity of titanium has been used to determine the coating thickness whereas the relative values of europium and titanium emission intensities provide data on the coating homogeneity. The obtained results show that the spin-coating technique provides better surface coverage with titanium dioxide. However, when the surface coating compositions were compared the dip-coating technique was more reliable.

  11. Europium(III) Macrocyclic Complexes with Alcohol Pendant Groups as Chemical Exchange Saturation Transfer Agents

    Science.gov (United States)

    Woods, Mark; Woessner, Donald E.; Zhao, Piyu; Pasha, Azhar; Yang, Meng-Yin; Huang, Ching-Hui; Vasalitiy, Olga; Morrow, Janet R.; Sherry, A. Dean

    2009-01-01

    Paramagnetic lanthanide(III) complexes that contain hyperfine-shifted exchangeable protons offer considerable advantages over diamagnetic molecules as chemical exchange saturation transfer (CEST) agents for MRI. As part of a program to investigate avenues to improve the sensitivity of such agents, the CEST characteristics of europium(III) macrocyclic complexes having appended hydroxyethyl groups were investigated. The CEST spectrum of the asymmetrical complex, EuCNPHC3+, shows five distinct peaks for each magnetically nonequivalent exchangeable proton in the molecule. The CEST spectra of this complex were fitted to NMR Bloch theory to yield exchange rates between each of six exchanging proton pools (five on the agent plus bulk water). Exchange between the Eu3+-bound hydroxyl protons and bulk water protons was slow in dry acetonitrile but accelerated incrementally upon stepwise addition of water. In pure water, exchange was too fast to observe a CEST effect. The utility of this class of europium(III) complex for CEST imaging applications is ultimately limited by the small chemical shifts induced by the hydroxyl-appended ligands of this type and the resulting small Δω values for the exchangeable hydroxyl protons. PMID:16881645

  12. Red light emission from europium doped zinc sodium bismuth borate glasses

    Science.gov (United States)

    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.

  13. Samarium-153 EDTMP for metastatic bone pain palliation: the impact of europium impurities.

    Science.gov (United States)

    Kalef-Ezra, J A; Valakis, S T; Pallada, S

    2015-02-01

    To evaluate the impact on the radiation protection policies of the radiocontaminants in Samarium-153 ethylenediamine tetramethylene phosphonate ((153)Sm-EDTMP). The internal contamination of patients treated with (153)Sm-EDMTP for palliation of painful disseminated multiple bone metastases due to long-lived impurities was assessed by direct measurements. These measurements were coupled with dose-rate measurements close to their bodies and spectroscopic analysis of the residual activity in post-treatment radiopharmaceutical vials. Whole-body counting carried out in six patients showed a 30-81-kBq europium -152 plus europium-154 contamination. The 0.85 mean (152)Eu- to -(154)Eu activity ratio obtained by direct counting was similar to that assessed by analysis of post-treatment residual activities in twelve radiopharmaceutical vials following radiopharmaceutical injection. The long-lived radiocontaminants in the patient's bodies and the treatment wastes require modifications of the applicable radiation protection policies. Copyright © 2014 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  14. Induced Europium Circularly Polarized Luminescence Monitors Reversible Drug Binding to Native α1 -Acid Glycoprotein.

    Science.gov (United States)

    Jennings, Laura; Waters, Ryan S; Pal, Robert; Parker, David

    2017-02-03

    Alpha-1-acid glycoprotein (α1 -AGP) is an important blood plasma glycoprotein. Following an acute-phase reaction such as stress, inflammation, burn, or infection, the bloodstream concentration of α1 -AGP can increase up to 400 % of its normal concentration. A wide range of drugs is known to bind α1 -AGP. Increased binding of pharmacologically active compounds to α1 -AGP moderates their clinical effect by decreasing the amount of unbound drug in the bloodstream. This has important clinical ramifications for such applications as the duration of anesthesia and in determining dosage for drug therapy. In this study, the competitive binding to α1 -AGP of a dynamically racemic europium(III) complex with seven pharmacologically active drugs absorbing in the range λ 250-290 nm was monitored by following changes in europium total emission and in induced circularly polarized luminescence (CPL). Binding affinities corresponding to Kd values in the range 0.5-100 μm were measured, in good agreement with published data. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Europium-doped amorphous calcium phosphate porous nanospheres: preparation and application as luminescent drug carriers

    Directory of Open Access Journals (Sweden)

    Zhang Kui-Hua

    2011-01-01

    Full Text Available Abstract Calcium phosphate is the most important inorganic constituent of biological tissues, and synthetic calcium phosphate has been widely used as biomaterials. In this study, a facile method has been developed for the fabrication of amorphous calcium phosphate (ACP/polylactide-block-monomethoxy(polyethyleneglycol hybrid nanoparticles and ACP porous nanospheres. Europium-doping is performed to enable photoluminescence (PL function of ACP porous nanospheres. A high specific surface area of the europium-doped ACP (Eu3+:ACP porous nanospheres is achieved (126.7 m2/g. PL properties of Eu3+:ACP porous nanospheres are investigated, and the most intense peak at 612 nm is observed at 5 mol% Eu3+ doping. In vitro cytotoxicity experiments indicate that the as-prepared Eu3+:ACP porous nanospheres are biocompatible. In vitro drug release experiments indicate that the ibuprofen-loaded Eu3+:ACP porous nanospheres show a slow and sustained drug release in simulated body fluid. We have found that the cumulative amount of released drug has a linear relationship with the natural logarithm of release time (ln(t. The Eu3+:ACP porous nanospheres are bioactive, and can transform to hydroxyapatite during drug release. The PL properties of drug-loaded nanocarriers before and after drug release are also investigated.

  16. "Rigid" Luminescent Soft Materials: Europium-Containing Lyotropic Liquid Crystals Based on Polyoxyethylene Phytosterols and Ionic Liquids.

    Science.gov (United States)

    Yi, Sijing; Wang, Jiao; Feng, Zhenyu; Chen, Xiao

    2017-10-05

    Soft materials of europium β-diketonate complexes constructed in lyotropic liquid crystals (LLCs) mediated by ionic liquids (ILs) are impressive for their excellent luminescence performance and stability. For the aim to further improve their mechanical processability and luminescent tunablility, the polyoxyethylene phytosterols (BPS-n) were introduced here as structure directing agents to prepare relatively "rigid" lamellar luminescent LLCs in 1-butyl-3-methyl-imidazolium hexafluorophosphate by doping europium β-diketonate complexes with different imidazolium counterions. As a result of the solvophobic sterol ring structure of BPS-n, the more effective isolation and confinement effects of europium complexes could be achieved. The longest fluorescence lifetime and the highest quantum efficiency reported so far for europium containing lyotropic organized soft materials were thus obtained. Changing the molecular structures of BPS-n with different oxyethylene chains or doped complexes with imidazolium counterions of different alkyl chain lengths, the spacings of lamellar LLC matrixes and position of dispersed complexes became tunable. The measured luminescent and rheological properties for such composite LLCs showed a dependence on the rigidity and isolation capability afforded by sterol molecules. It was also found that the increase of counterion alkyl chain length would weaken the LLC matrix's confinement and isolation effects and therefore exhibit the deteriorated luminescence performance. The enhanced luminescence efficiency and stability of doped BPS-n LLCs reflected the excellent segregation of europium complexes from each other and therefore the reduced self-quenching process. The obtained results here present the designability of LLC matrixes and their great potential to promote achieving the luminescence tunability of soft materials.

  17. Preparation and photoluminescence of some europium (III) ternary complexes with β-diketone and nitrogen heterocyclic ligands

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dunjia, E-mail: dunjiawang@163.com; Pi, Yan; Zheng, Chunyang; Fan, Ling; Hu, Yanjun; Wei, Xianhong

    2013-10-15

    Highlights: •Preparation of europium (III) ternary complexes with β-diketone and nitrogen heterocyclic ligands. •Photoluminescence behavior of europium (III) ternary complexes. •Analysis of the Judd–Ofelt intensity parameters (Ω{sub t}), the lifetime (τ) and the luminescent quantum yield (η). -- Abstract: Preparation and photoluminescence behavior of four new europium (III) ternary complexes with β-diketones (1-(6-methoxy-naphthalen-2-yl)-3-phenyl-propane-1,3-dione (MNPPD) and 1-(4-tert-butyl-phenyl)-3-(6-methoxy-naphthalen-2-yl)-propane-1,3-dione (BPMPD)) and 2,2-dipyridine (Bipy) or 1,10-phenanthroline (Phen) were reported, in the solid state. Complexes Eu(MPPD){sub 3}·Bipy, Eu(BMPD){sub 3}·Bipy, Eu(MPPD){sub 3}·Phen and Eu(BMPD){sub 3}·Phen were characterized by elemental analysis, FT-IR, {sup 1}H NMR, UV–vis absorption. The emission spectra show narrow emission bands that arise from the {sup 5}D{sub 0} → {sup 7}F{sub J} (J = 0–4) transitions of the europium ion. Based on the emission spectra and luminescence decay curves in solid state, the intensity parameters (Ω{sub t}), lifetime (τ) and emission quantum efficiency (η) were determined. The Ω{sub 2} values indicate that the Eu(III) ion in these complexes is in a highly polarizable chemical environment. Complexes Eu(MPPD){sub 3}·Bipy and Eu(MPPD){sub 3}·Phen showed a longer lifetime (τ) and a higher luminescence quantum efficiency (η), which indicated that the energy transfer to the europium ion from MNPPD ligand is more efficient than that from BPMPD ligand.

  18. Luminescent method of determination of composition of europium and terbium complexes in solution by change of intensity ratio of luminescence bands

    Energy Technology Data Exchange (ETDEWEB)

    Bel' tyukova, S.V.; Nazarenko, N.A.; Poluehktov, N.S.

    1982-03-01

    The complexes of europium and terbium with phenanthroline, ethylenediaminetetraacetate, nitrilotriacetate, some acids-phenol derivatives and ..beta..-diketones series have been used as an example to demonstrate that the value of the ratio of intensities on the two bands of europium(terbium) luminescence spectra - the one corresponding to the hypersensitive'' transition and the other, to the magnetic dipole one - can be used for determination of the complexes composition in solutions.

  19. Syntheses and electroluminescent properties of two europium ternary complexes Eu(DBM){sub 3}(PBO) and Eu(DBM){sub 3}(PBT)

    Energy Technology Data Exchange (ETDEWEB)

    Guan Min [State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, Beijing 100871 (China); Gao Lihua [Department of Chemistry, Beijing Normal University, Beijing 100875 (China); Wang Shanshan [State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, Beijing 100871 (China); Huang Chunhui [State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, Beijing 100871 (China)], E-mail: chhuang@pku.edu.cn; Wang Kezhi [Department of Chemistry, Beijing Normal University, Beijing 100875 (China)

    2007-12-15

    Two europium complexes, Eu(DBM){sub 3}(PBO) and Eu(DBM){sub 3}(PBT) (DBM=dibenzoylmethanato, PBO=2-(2-pyridyl)benzoxazole, PBT=2-(2-pyridyl)benzothiazole), were prepared and used as emitting materials in organic electroluminescent (EL) devices. The devices with the structures ITO/TPD/Eu(DBM){sub 3}(PBO) (or Eu(DBM){sub 3}(PBT)/BCP/Alq{sub 3}/Mg:Ag/Ag emit red light originating from the europium complexes.

  20. Stability constants of europium complexes with a nitrogen heterocycle substituted methane-1,1-diphosphonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, M.P.; Rickert, P.G.; Schmidt, M.A.; Nash, K.L.

    1996-06-01

    Even in moderately acidic solutions ([H{sup +}] > 0.01 M), N-piperidinomethane-1,1-diphosphonic acid (H{sub 4}PMDPA) is a strong complexant of trivalent lanthanide ions that shows enhanced complex solubility over previously studied 1,1-diphosphonic acids. The protonation constants of PMDPA in 2.0 M H/NaClO{sub 4} were determined by potentiometric and NMR titrations, and the stability constants for formation of complexes with Eu{sup 3+} were determined by solvent extraction. Difference in protonation equilibria induced by addition of the nitrogen heterocycle results in an increase in the complexation strength of PMDPA. In solutions containing 0.1 M H{sup +} and ligand concentrations greater than 0.02 M, PMDPA is the most effective 1,1-diphosphonic acid for europium complexation studied thus far.

  1. Sorption of Europium in zirconium silicate; Sorcion de Europio en silicato de circonio

    Energy Technology Data Exchange (ETDEWEB)

    Garcia R, G. [ININ, Carretera Mexico-Toluca Km. 36.5, 52045 Estado de Mexico (Mexico)

    2004-07-01

    Some minerals have the property of sipping radioactive metals in solution, that it takes advantage to manufacture contention barriers that are placed in the repositories of nuclear wastes. The more recent investigations are focused in the development of new technologies guided to the sorption of alpha emissors on minerals which avoid their dispersion in the environment. In an effort to contribute to the understanding of this type of properties, some studies of sorption of Europium III are presented like homologous of the americium, on the surface of zirconium silicate (ZrSiO{sub 4}). In this work the results of sorption experiences are presented as well as the interpretation of the phenomena of the formation of species in the surface of the zirconium silicate. (Author)

  2. First principles description of the insulator-metal transition in europium monoxide

    KAUST Repository

    Wang, Hao

    2012-02-01

    Europium monoxide, EuO, is a ferromagnetic insulator. Its electronic structure under pressure and doping is investigated by means of density functional theory. We employ spin polarized electronic structure calculations including onsite electron-electron interaction for the localized Eu 4f and 5d electrons. Our results show that under pressure the ferromagnetism is stable, both for hydrostatic and uniaxial pressure, while the compound undergoes an insulator-metal transition. The insulator-metal transition in O deficient and Gd doped EuO is reproduced for an impurity concentration of 6.25%. A 10 monolayer thick EuO(1 0 0) thin film is predicted to be an insulator with a narrow band gap of 0.08 eV. © 2011 Elsevier B.V. All rights reserved.

  3. Development of europium doped BaSO4 TL OSL dual phosphor for radiation dosimetry applications

    Science.gov (United States)

    Patle, Anita; Patil, R. R.; Kulkarni, M. S.; Bhatt, B. C.; Moharil, S. V.

    2015-08-01

    This paper presents the results on the preparation and characterization of Europium-doped Barium sulfate (BaSO4: Eu) TL /OSL dual phosphor. The OSL sensitivity was found to be 11% of the commercially available Al2O3: C, using area integration method. The sample also shows good TL sensitivity and the dosimetric peak appears around 190°C with a shoulder at 282°C. After OSL readout, No change in the TL glow curve is observed. Since the observed TL peaks are not responsible for the observed OSL, good OSL as well as TL sensitivity and low fading will make this phosphor suitable for applications in radiation dosimetry using OSL as well as TL.

  4. Chemiluminescence determination of tetracyclines using Fenton system in the presence europium(III) ions

    Energy Technology Data Exchange (ETDEWEB)

    Kaczmarek, Malgorzata [Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60 - 780 Poznan (Poland); Lis, Stefan, E-mail: blis@amu.edu.pl [Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60 - 780 Poznan (Poland)

    2009-04-20

    A new simple chemiluminescent method for the determination of chlortetracycline (Chlor-TC), oxytetracycline (Oxy-TC) and doxycycline (Doxy-TC) is described. This method is based on the europium(III) emission as a result of the energy transfer process from the excited product of the tetracyclines oxidation to the uncomplexed Eu(III). Under the optimum conditions, calibration graphs were obtained for 4 x 10{sup -7} to 2 x 10{sup -5} mol L{sup -1} of Chlor-TC; 2 x 10{sup -7} to 2 x 10{sup -5} mol L{sup -1} of Oxy-TC and 1 x 10{sup -7} to 3 x 10{sup -5} mol L{sup -1} of Doxy-TC. The method was successfully applied to the determination of these drugs in pharmaceutical and veterinary formulation and honey.

  5. Europium-doped aluminum oxide phosphors as indicators for frontal polymerization dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Carranza, Arturo; Gewin, Mariah; Pojman, John A., E-mail: japojman@lsu.edu [Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804 (United States)

    2014-06-15

    In this study, we present an inexpensive and practical method that allows the monitoring and visualization of front polymerization, propagation, and dynamics. Commercially available europium-doped aluminum oxide powders were combined with video imaging to visualize free-radical propagating polymer fronts. In order to demonstrate the applicability of this method, frontal copolymerization reactions of propoxylated glycerin triacrylate (EB53), pentaerythritol triacrylate (PETA), and pentaerythritol tetra-acrylate (PETEA) with 1,1-Bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane (Luperox 231®) as an initiator were studied and compared to the results obtained by IR imaging. Systems exhibiting higher filler loading, higher EB53 content, and less acrylated monomers showed a marked decrease in front velocity, while those with more acrylated monomers and higher crosslinking density showed a marked increase in front velocity. Finally, in order to show the potential of the imaging technique, we studied fronts propagating in planar and spherical geometries.

  6. Europium-doped aluminum oxide phosphors as indicators for frontal polymerization dynamics.

    Science.gov (United States)

    Carranza, Arturo; Gewin, Mariah; Pojman, John A

    2014-06-01

    In this study, we present an inexpensive and practical method that allows the monitoring and visualization of front polymerization, propagation, and dynamics. Commercially available europium-doped aluminum oxide powders were combined with video imaging to visualize free-radical propagating polymer fronts. In order to demonstrate the applicability of this method, frontal copolymerization reactions of propoxylated glycerin triacrylate (EB53), pentaerythritol triacrylate (PETA), and pentaerythritol tetra-acrylate (PETEA) with 1,1-Bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane (Luperox 231®) as an initiator were studied and compared to the results obtained by IR imaging. Systems exhibiting higher filler loading, higher EB53 content, and less acrylated monomers showed a marked decrease in front velocity, while those with more acrylated monomers and higher crosslinking density showed a marked increase in front velocity. Finally, in order to show the potential of the imaging technique, we studied fronts propagating in planar and spherical geometries.

  7. Electrochemiluminescence Study of Europium (III Complex with Coumarin3-Carboxylic Acid

    Directory of Open Access Journals (Sweden)

    Stefan Lis

    2008-01-01

    Full Text Available The europium (III complex of coumarin-3-carboxylic acid (C3CA has been prepared and characterized on the basis of elemental analysis, IR, and emission (photoluminescence and electrochemiluminescence spectroscopy. The synthesised complex having a formula Eu(C3CA2(NO3(H2O2 was photophysically characterized in solution and in the solid state. Electrochemiluminescence, ECL, of the system containing the Eu(III/C3CA complex was studied using an oxide-covered aluminium electrode. The goal of these studies was to show the possibility of the use of electrochemical excitation of the Eu(III ion in aqueous solution for emission generation. The generated ECL emission was very weak, and therefore its measurements and spectral analysis were carried out with the use of cut-off filters method. The studies proved a predominate role of the ligand-to-metal energy transfer (LMET in the generated ECL.

  8. Europium incorporated in silica matrix obtained by sol-gel: luminescent materials

    Directory of Open Access Journals (Sweden)

    Nassar Eduardo José

    2003-01-01

    Full Text Available In this work we report some aspects of the chemistry involved in the preparation of modified silicon oxide by the sol-gel process. Europium III compounds were used as luminescent probe. An organic-inorganic hybrid was obtained by hydrolysis of tetraethylorthosilicate (TEOS and 3-aminopropyltriethoxysilane (APTS. The Eu III compounds were added in different ways. In the first, silica was prepared in the presence of Eu III, and in the second, Eu III was added on the silica surface. These materials were studied by luminescence, infrared spectroscopy and termogravimetric analysis. The results obtained for the hybrid material show different behavior for Eu III emission, which could be excited by the antenna effect and the influence of the surrounding in the luminescence quenching. The thermogravimetric data present different mass loss in samples to range temperature 50 - 150 °C. Thermogravimetric and infrared spectra showed that inorganic polymers incorporated the organic part.

  9. Europium as an inhibitor of Amyloid-β(1-42) induced membrane permeation.

    Science.gov (United States)

    Williams, Thomas L; Urbanc, Brigita; Marshall, Karen E; Vadukul, Devkee M; Jenkins, A Toby A; Serpell, Louise C

    2015-10-24

    Soluble Amyloid-beta (Aβ) oligomers are a source of cytotoxicity in Alzheimer's disease (AD). The toxicity of Aβ oligomers may arise from their ability to interact with and disrupt cellular membranes mediated by GM1 ganglioside receptors within these membranes. Therefore, inhibition of Aβ-membrane interactions could provide a means of preventing the toxicity associated with Aβ. Here, using Surface Plasmon field-enhanced Fluorescence Spectroscopy, we determine that the lanthanide, Europium III chloride (Eu(3+)), strongly binds to GM1 ganglioside-containing membranes and prevents the interaction with Aβ42 leading to a loss of the peptides ability to cause membrane permeation. Here we discuss the molecular mechanism by which Eu(3+) inhibits Aβ42-membrane interactions and this may lead to protection of membrane integrity against Aβ42 induced toxicity. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  10. Radiation effects on beta /10.6/ of pure and europium doped KCl

    Science.gov (United States)

    Grimes, H. H.; Maisel, J. E.; Hartford, R. H.

    1975-01-01

    Changes in the optical absorption coefficient as the result of X-ray and electron bombardment of pure monocrystalline and polycrystalline KCl and of divalent europium doped polycrystalline KCl were determined. A constant heat flow calorimetric method was used to measure the optical absorption coefficients. Both 300 kV X-ray irradiation and 2 MeV electron irradiation produced increases in the optical absorption coefficient at room temperature. X-ray irradiation produced more significant changes in pure monocrystalline KCl than equivalent amounts of electron irradiation. Electron irradiation of pure and Eu-doped polycrystalline KCl produced increases in the absorption by as much as a factor of 20 over untreated material. Bleaching of the electron-irradiated doped KCl with 649 millimicron light produced a further increase.

  11. Excitation functions for the formation of longer lived isotopes by deuteron irradiation of Europium

    Energy Technology Data Exchange (ETDEWEB)

    Takács, S., E-mail: stakacs@atomki.hu [Institute for Nuclear Research, Hungarian Academy of Sciences, 4026 Debrecen (Hungary); Tárkányi, F. [Institute for Nuclear Research, Hungarian Academy of Sciences, 4026 Debrecen (Hungary); Hermanne, A.; Adam-Rebeles, R. [Cyclotron Laboratory, Vrije Universiteit Brussel, Brussels 1090 (Belgium); Takács, M.P. [Institute for Nuclear Research, Hungarian Academy of Sciences, 4026 Debrecen (Hungary); Institute of Physics, University of Debrecen, 4026 Debrecen (Hungary)

    2013-09-01

    Excitation functions for nuclear reactions induced on natural europium targets by energetic deuterons were studied up to 50 MeV. A standard stacked foil technique was used for irradiation and high resolution gamma spectrometry was applied for activity assessment. Direct or cumulative cross sections for reaction products with half-life longer than 2 h were determined. Reactions leading to the formation of the radionuclides {sup 147,149,151,153}Gd, {sup 147,148,149,150m,150g,152m,152g,154g}Eu, {sup 153}Sm and {sup 150}Pm were studied. In most cases no earlier data were available in the literature. The new experimental results were compared with values tabulated in the on-line TENDL2011 library.

  12. Quadrupole splitting and Eu partial lattice dynamics in europium orthophosphate EuPO {sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Klobes, B., E-mail: b.klobes@fz-juelich.de [JARA-FIT - Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science JCNS and Peter Grünberg Institute PGI (Germany); Arinicheva, Y., E-mail: y.arinicheva@fz-juelich.de; Neumeier, S., E-mail: s.neumeier@fz-juelich.de [Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research (IEK-6) Nuclear Waste Management and Reactor Safety (Germany); Simon, R. E., E-mail: r.simon@fz-juelich.de; Jafari, A., E-mail: a.jafari@fz-juelich.de [JARA-FIT - Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science JCNS and Peter Grünberg Institute PGI (Germany); Bosbach, D., E-mail: d.bosbach@fz-juelich.de [Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research (IEK-6) Nuclear Waste Management and Reactor Safety (Germany); Hermann, R. P., E-mail: hermannrp@ornl.gov [JARA-FIT - Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science JCNS and Peter Grünberg Institute PGI (Germany)

    2016-12-15

    Hyperfine interactions in europium orthophosphate EuPO{sub 4} were investigated using {sup 151}Eu Mössbauer spectroscopy from 6 to 300 K. The value of the quadrupole splitting and the asymmetry parameter were refined and further substantiated by nuclear forward scattering data obtained at room temperature. The temperature dependence of the relative absorption was modeled with an Eu specific Debye temperature of 221(1) K. Eu partial lattice dynamics were probed by means of nuclear inelastic scattering and the mean force constant, the Lamb-Mössbauer factor, the internal energy, the vibrational entropy, the average phonon group velocity were calculated using the extracted density of phonon states. In general, Eu specific vibrations are characterized by rather small phonon energies and contribute strongly to the total entropy of the system. Although there is no classical Debye like behavior at low vibrational energies, the average phonon group velocity can be reasonably approximated using a linear fit.

  13. 27 CFR 53.156 - Extension of time for paying tax shown on return.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Extension of time for paying tax shown on return. 53.156 Section 53.156 Alcohol, Tobacco Products and Firearms ALCOHOL AND... property at a sacrifice price, will result to the taxpayer from making payment on the due date of the...

  14. The role of miR156/SPLs modules in Arabidopsis lateral root development.

    Science.gov (United States)

    Yu, Niu; Niu, Qi-Wen; Ng, Kian-Hong; Chua, Nam-Hai

    2015-08-01

    miR156 is an evolutionarily highly conserved miRNA in plants that defines an age-dependent flowering pathway. The investigations thus far have largely, if not exclusively, confined to plant aerial organs. Root branching architecture is a major determinant of water and nutrients uptake for plants. We show here that MIR156 genes are differentially expressed in specific cells/tissues of lateral roots. Plants overexpressing miR156 produce more lateral roots whereas reducing miR156 levels leads to fewer lateral roots. We demonstrate that at least one representative from the three groups of miR156 targets SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) genes: SPL3, SPL9 and SPL10 are involved in the repression of lateral root growth, with SPL10 playing a dominant role. In addition, both MIR156 and SPLs are responsive to auxin signaling suggesting that miR156/SPL modules might be involved in the proper timing of the lateral root developmental progression. Collectively, these results unravel a role for miR156/SPLs modules in lateral root development in Arabidopsis. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  15. 40 CFR 80.156 - Liability for violations of the interim detergent program controls and prohibitions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Liability for violations of the interim detergent program controls and prohibitions. 80.156 Section 80.156 Protection of Environment... operating under such refiner's corporate, trade, or brand name or that of any of its marketing subsidiaries...

  16. 47 CFR 80.303 - Watch on 156.800 MHz (Channel 16).

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Watch on 156.800 MHz (Channel 16). 80.303 Section 80.303 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO... Watches § 80.303 Watch on 156.800 MHz (Channel 16). (a) During its hours of operation, each coast station...

  17. 47 CFR 80.148 - Watch on 156.8 MHz (Channel 16).

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Watch on 156.8 MHz (Channel 16). 80.148 Section 80.148 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO... Watches § 80.148 Watch on 156.8 MHz (Channel 16). Each compulsory vessel, while underway, must maintain a...

  18. Photoluminescent polymer electrolyte based on agar and containing europium picrate for electrochemical devices

    Energy Technology Data Exchange (ETDEWEB)

    Lima, E. [Centro de Quimica, Universidade do Minho, Gualtar, 4710-057 Braga (Portugal); Raphael, E.; Sentanin, F. [IQSC, Universidade de Sao Paulo, 13566-590 Sao Carlos, SP (Brazil); Rodrigues, L.C. [Centro de Quimica, Universidade do Minho, Gualtar, 4710-057 Braga (Portugal); Ferreira, R.A.S.; Carlos, L.D. [Departamento de Fisica, CICECO, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Silva, M.M., E-mail: nini@quimica.uminho.pt [Centro de Quimica, Universidade do Minho, Gualtar, 4710-057 Braga (Portugal); Pawlicka, A. [IQSC, Universidade de Sao Paulo, 13566-590 Sao Carlos, SP (Brazil)

    2012-04-15

    Highlights: Black-Right-Pointing-Pointer We prepared ionic conducting membranes for the specific requirements of the device. Black-Right-Pointing-Pointer Luminescent reporter groups, with many applications in biotechnology. Black-Right-Pointing-Pointer Thermal and electrochemical stability of electrolytes is adequate for application. - Abstract: Dispersion of photoluminescent rare earth metal complexes in polymer matrices is of great interest due to the possibility of avoiding the saturation of the photoluminescent signal. The possibility of using a natural ionic conducting polymer matrix was investigated in this study. Samples of agar-based electrolytes containing europium picrate were prepared and characterized by physical and chemical analyses. The FTIR spectra indicated strong interaction of agar O-H and 3,6-anhydro-galactose C-O groups with glycerol and europium picrate. The DSC analyses revealed no glass transition temperature of the samples in the -60 to 250 Degree-Sign C range. From the thermogravimetry (TG), a thermal stability of the samples of up to 180 Degree-Sign C was stated. The membranes were subjected to ionic conductivity measurement, which provided the values of 2.6 Multiplication-Sign 10{sup -6} S/cm for the samples with acetic acid and 1.6 Multiplication-Sign 10{sup -5} S/cm for the samples without acetic acid. Moreover, the temperature-dependent ionic conductivity measurements revealed both Arrhenius and VTF models of the conductivity depending on the sample. Surface visualization through scanning electron microscopy (SEM) demonstrated good uniformity. The samples were also applied in small electrochromic devices and showed good electrochemical stability. The present work confirmed that these materials may perform as satisfactory multifunctional component layers in the field of electrochemical devices.

  19. Spectroscopic investigation on europium doped heavy metal borate glasses for red luminescent application

    Energy Technology Data Exchange (ETDEWEB)

    Hegde, Vinod; Wagh, Akshatha; Kamath, Sudha D. [Manipal University, Department of Physics, Manipal Institute of Technology, Manipal (India); Hegde, Hemanth [Manipal University, Department of Chemistry, Manipal Institute of Technology, Manipal (India); Vishwanath, C.S.D. [Sri Venkateswara University, Department of Physics, Tirupati (India)

    2017-05-15

    The present study explores a new borate family glasses based on 10ZnO-5Na{sub 2}O-10Bi{sub 2}O{sub 3}-(75 - x) B{sub 2}O{sub 3}-xEu{sub 2}O{sub 3} (x = 0, 0.1, 0.5, 1, 1.5, 2, 3 mol%) composition, synthesized by rapid melt quench technique. Prepared glasses were subjected to the density and refractive index measurements and their values were used to calculate other physical properties of the glass matrix as a function of Eu{sup 3+} concentration. XRD confirmed amorphous nature of the glasses. FTIR spectra in the absorption mode were recorded in the 400-4000 cm{sup -1} region to identify different functional groups in the glass matrix. Deconvoluted FTIR spectra showed increase in BO{sub 4} units with rise in europium content which confirmed the 'network strengthener' role of europium ions by creating bridging oxygens (BOs). Optical properties were investigated for their luminescence behavior through various spectroscopic techniques such as UV-Vis-NIR absorption, excitation, emission, decay profiles, and color measurements at room temperature. Lasing properties of the glasses like total radiative life time, branching ratio, emission cross section, and optical gain were obtained from the calculated Judd-Ofelt (Ω{sub 2},Ω{sub 4}) intensity parameters. From the measured values of emission, cross sections, branching ratios, life times, strong photoluminescence features, and CIE chromaticity coordinates, 0.5 mol% of Eu{sup 3+} ions doped ZnNaBiB glasses showed optimum performance and are potential candidate for red light generation at 613 nm. (orig.)

  20. Europium nanoparticle-based high performing immunoassay for the screening of treponemal antibodies.

    Directory of Open Access Journals (Sweden)

    Sheikh M Talha

    Full Text Available Treponema pallidum subspecies pallidum (Tp is the causative agent of syphilis which mainly spreads through sexual contact, blood transfusion and perinatal route. In order to curtail the spread of the infection and to clinically manage the disease, timely, accurate and reliable diagnosis is very important. We have developed an immunoassay for the detection of treponemal antibodies in human serum or plasma samples. In vivo biotinylated and non-biotinylated versions of the recombinant antigen were designed by the fusion of three Tp-specific antigens namely Tp15, Tp17 and Tp47. These fusion antigens were expressed in E. coli and purified using single-step metal affinity chromatography. Biotinylated fusion antigen immobilized on streptavidin coated plate was used to capture the treponemal antibodies and the non-biotinylated antigen coated on europium nanoparticles was used as tracer. Assays with two different incubation times of 10 min and 1 h were developed, and following the incubation the europium fluorescence was measured using time-resolved fluorometry. The developed time-resolved fluorometric (TRF immunoassays were evaluated with in-house and commercial serum/plasma sample panels. For well-established treponemal antibodies positive or negative samples, the sensitivity of TRF immunoassay with 10 min incubation time was 97.4%, and of TRF immunoassay with 1 h incubation time was 98.7%, and the specificities of both the TRF immunoassays were 99.2%. For the samples with discordant results with the reference assays, both the TRF immunoassays showed better specificity than the Enzygnost syphilis enzyme immunoassay as a screening test. The two different incubation times did not have any significant effect on the signal to cutoff (S/Co ratios obtained with the two immunoassays (p=0.06. Our results indicate that the developed immunoassay with a short incubation time of 10 min has the potential to be used in clinical laboratories and in blood

  1. Visible-light-excited and europium-emissive nanoparticles for highly-luminescent bioimaging in vivo.

    Science.gov (United States)

    Wu, Yongquan; Shi, Mei; Zhao, Lingzhi; Feng, Wei; Li, Fuyou; Huang, Chunhui

    2014-07-01

    Europium(III)-based material showing special milliseconds photoluminescence lifetime has been considered as an ideal time-gated luminescence probe for bioimaging, but is still limited in application in luminescent small-animal bioimaging in vivo. Here, a water-soluble, stable, highly-luminescent nanosystem, Ir-Eu-MSN (MSN = mesoporous silica nanoparticles, Ir-Eu = [Ir(dfppy)2(pic-OH)]3Eu·2H2O, dfppy = 2-(2,4-difluorophenyl)pyridine, pic-OH = 3-hydroxy-2-carboxypyridine), was developed by an in situ coordination reaction to form an insoluble dinuclear iridium(III) complex-sensitized-europium(III) emissive complex within mesoporous silica nanoparticles (MSNs) which had high loading efficiency. Compared with the usual approach of physical adsorption, this in-situ reaction strategy provided 20-fold the loading efficiency (43.2%) of the insoluble Ir-Eu complex in MSNs. These nanoparticles in solid state showed bright red luminescence with high quantum yield of 55.2%, and the excitation window extended up to 470 nm. These Ir-Eu-MSN nanoparticles were used for luminescence imaging in living cells under excitation at 458 nm with confocal microscopy, which was confirmed by flow cytometry. Furthermore, the Ir-Eu-MSN nanoparticles were successfully applied into high-contrast luminescent lymphatic imaging in vivo under low power density excitation of 5 mW cm(-2). This synthetic method provides a universal strategy of combining hydrophobic complexes with hydrophilic MSNs for in vivo bioimaging. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Europium Nanoparticle-Based High Performing Immunoassay for the Screening of Treponemal Antibodies

    Science.gov (United States)

    Talha, Sheikh M.; Hytönen, Jukka; Westhorpe, Adam; Kumar, Sushil; Khanna, Navin; Pettersson, Kim

    2013-01-01

    Treponema pallidum subspecies pallidum (Tp) is the causative agent of syphilis which mainly spreads through sexual contact, blood transfusion and perinatal route. In order to curtail the spread of the infection and to clinically manage the disease, timely, accurate and reliable diagnosis is very important. We have developed an immunoassay for the detection of treponemal antibodies in human serum or plasma samples. In vivo biotinylated and non-biotinylated versions of the recombinant antigen were designed by the fusion of three Tp-specific antigens namely Tp15, Tp17 and Tp47. These fusion antigens were expressed in E. coli and purified using single-step metal affinity chromatography. Biotinylated fusion antigen immobilized on streptavidin coated plate was used to capture the treponemal antibodies and the non-biotinylated antigen coated on europium nanoparticles was used as tracer. Assays with two different incubation times of 10 min and 1 h were developed, and following the incubation the europium fluorescence was measured using time-resolved fluorometry. The developed time-resolved fluorometric (TRF) immunoassays were evaluated with in-house and commercial serum/plasma sample panels. For well-established treponemal antibodies positive or negative samples, the sensitivity of TRF immunoassay with 10 min incubation time was 97.4%, and of TRF immunoassay with 1 h incubation time was 98.7%, and the specificities of both the TRF immunoassays were 99.2%. For the samples with discordant results with the reference assays, both the TRF immunoassays showed better specificity than the Enzygnost syphilis enzyme immunoassay as a screening test. The two different incubation times did not have any significant effect on the signal to cutoff (S/Co) ratios obtained with the two immunoassays (p = 0.06). Our results indicate that the developed immunoassay with a short incubation time of 10 min has the potential to be used in clinical laboratories and in blood-bank settings as a

  3. Semiconducting polymer encapsulated mesoporous silica particles with conjugated Europium complexes: toward enhanced luminescence under aqueous conditions.

    Science.gov (United States)

    Zhang, Jixi; Prabhakar, Neeraj; Näreoja, Tuomas; Rosenholm, Jessica M

    2014-01-01

    Immobilization of lanthanide organic complexes in meso-organized hybrid materials for luminescence applications have attracted immense interest due to the possibility of controlled segregation at the nanoscopic level for novel optical properties. Aimed at enhancing the luminescence intensity and stability of the hybrid materials in aqueous media, we developed polyvinylpyrrolidone (PVP) stabilized, semiconducting polymer (poly(9-vinylcarbazole), PVK) encapsulated mesoporous silica hybrid particles grafted with Europium(III) complexes. Monosilylated β-diketonate ligands (1-(2-naphthoyl)-3,3,3-trifluoroacetonate, NTA) were first co-condensed in the mesoporous silica particles as pendent groups for bridging and anchoring the lanthanide complexes, resulting in particles with an mean diameter of ∼ 450 nm and a bimodal pore size distribution centered at 3.5 and 5.3 nm. PVK was encapsulated on the resulted particles by a solvent-induced surface precipitation process, in order to seal the mesopores and protect Europium ions from luminescence quenching by producing a hydrophobic environment. The obtained polymer encapsulated MSN-EuLC@PVK-PVP particles exhibit significantly higher intrinsic quantum yield (Φ(Ln) = 39%) and longer lifetime (τ(obs) = 0.51 ms), as compared with those without polymer encapsulation. Most importantly, a high luminescence stability was realized when MSN-EuLC@PVK-PVP particles were dispersed in various aqueous media, showing no noticeable quenching effect. The beneficial features and positive attributes of both mesoporous silica and semiconducting polymers as lanthanide-complex host were merged in a single hybrid carrier, opening up the possibility of using these hybrid luminescent materials under complex aqueous conditions such as biological/physiological environments.

  4. Surface-imprinted nanofilaments for europium-amplified luminescent detection of fluoroquinolone antibiotics.

    Science.gov (United States)

    Zdunek, Jolanta; Benito-Peña, Elena; Linares, Ana; Falcimaigne-Cordin, Aude; Orellana, Guillermo; Haupt, Karsten; Moreno-Bondi, María C

    2013-07-29

    The development and characterization of novel, molecularly imprinted polymer nanofilament-based optical sensors for the analysis of enrofloxacin, an antibiotic widely used for human and veterinary applications, is reported. The polymers were prepared by nanomolding in porous alumina by using enrofloxacin as the template. The antibiotic was covalently immobilized on to the pore walls of the alumina by using different spacers, and the prepolymerization mixture was cast in the pores and the polymer synthesized anchored onto a glass support through UV polymerization. Various parameters affecting polymer selectivity were evaluated to achieve optimal recognition, namely, the spacer arm length and the binding solvent. The results of morphological characterization, binding kinetics, and selectivity of the optimized polymer material for ENR and its derivatives are reported. For sensing purposes, the nanofilaments were incubated in solutions of the target molecule in acetonitrile/HEPES buffer (100 mM, pH 7.5, 50:50, v/v) for 20 min followed by incubation in a 10 mM solution of europium(III) ions to generate a europium(III)-enrofloxacin complex on the polymer surface. The detection event was based on the luminescence of the rare-earth ion (λexc=340 nm; λem=612 nm) that results from energy transfer from the antibiotic excited state to the metal-ion emitting excited state. The limit of detection of the enrofloxacin antibiotic was found to be 0.58 μM. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Faster Synthesis of Beta-Diketonate Ternary Europium Complexes: Elapsed Times & Reaction Yields.

    Science.gov (United States)

    Lima, Nathalia B D; Silva, Anderson I S; Gerson, P C; Gonçalves, Simone M C; Simas, Alfredo M

    2015-01-01

    β-diketonates are customary bidentate ligands in highly luminescent ternary europium complexes, such as Eu(β-diketonate)3(L)2, where L stands for a nonionic ligand. Usually, the syntheses of these complexes start by adding, to an europium salt such as EuCl3(H2O)6, three equivalents of β-diketonate ligands to form the complexes Eu(β-diketonate)3(H2O)2. The nonionic ligands are subsequently added to form the target complexes Eu(β-diketonate)3(L)2. However, the Eu(β-diketonate)3(H2O)2 intermediates are frequently both difficult and slow to purify by recrystallization, a step which usually takes a long time, varying from days to several weeks, depending on the chosen β-diketonate. In this article, we advance a novel synthetic technique which does not use Eu(β-diketonate)3(H2O)2 as an intermediate. Instead, we start by adding 4 equivalents of a monodentate nonionic ligand L straight to EuCl3(H2O)6 to form a new intermediate: EuCl3(L)4(H2O)n, with n being either 3 or 4. The advantage is that these intermediates can now be easily, quickly, and efficiently purified. The β-diketonates are then carefully added to this intermediate to form the target complexes Eu(β-diketonate)3(L)2. For the cases studied, the 20-day average elapsed time reduced to 10 days for the faster synthesis, together with an improvement in the overall yield from 42% to 69%.

  6. Modified magnetic and optical properties of manganese nanoparticles incorporated europium doped magnesium borotellurite glass

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, Siti Maisarah; Sahar, M.R., E-mail: mrahim057@gmail.com; Ghoshal, S.K.

    2017-02-01

    This paper reports the modified optical and magnetic properties of europium (Eu{sup 3+}) ions doped and Manganese nanoparticles (NPs) embedded Magnesium Borotellurite glass synthesized via melt quenching method. The influence of varying Mn NPs concentrations on the magnetic, absorption and emission properties of such glass samples are determined. Stables, transparent and amorphous glasses are obtained. The observed modification of the electronic polarizability is interpreted in terms of the generation of non-bridging oxygen (NBO) and bridging oxygen (BO) in the amorphous network. TEM images manifested the growth of Mn NPs with average diameter 11±1 nm. High-resolution TEM reveals that the lattice spacing of manganese nanoparticles is 0.308 nm at (112) plane. The emission spectra revealed four prominent peaks centered at 587 nm, 610 nm, 651 nm and 700 nm assigned to the transition from {sup 5}D{sub 0} →{sup 7}F{sub J} (J=1, 2, 3, 4) states of Eu{sup 3+} ion. A significant drop in the luminescence intensity due to the incorporation of Mn NPs is ascribed to the enhanced energy transfer from the Eu{sup 3+} ion to NPs. Prepared glass systems exhibited paramagnetic behavior. - Highlights: • The europium doped magnesium borotellurite glasses embedded Mn NPs prepared using the conventional melt-quenching method. • The TEM result reveals the size of Mn NPs while its planar spacing has been determined by HRTEM. • The luminescence properties of TeO{sub 2}–B{sub 2}O{sub 3}–MgO–Eu{sub 2}O{sub 3}–Mn{sub 3}O{sub 4} glasses have been investigated as effect of Mn NPs content. • The magnetization measurement of glass sample is carried out using vibrating sample magnetometer (VSM)

  7. Red polymer light-emitting devices based on an oxadiazole-functionalized europium(III) complex

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yu, E-mail: liuyu03b@126.com [Department of Chemistry, Key Lab of Environment-Friendly Chemistry and Application in the Ministry of Education, Xiangtan University, Xiangtan 411105 (China); Wang, Yafei [Department of Chemistry, Key Lab of Environment-Friendly Chemistry and Application in the Ministry of Education, Xiangtan University, Xiangtan 411105 (China); Li, Chun [Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology, Guangzhou 510640 (China); Huang, Ying; Dang, Dongfeng; Zhu, Meixiang [Department of Chemistry, Key Lab of Environment-Friendly Chemistry and Application in the Ministry of Education, Xiangtan University, Xiangtan 411105 (China); Zhu, Weiguo, E-mail: zhuwg18@126.com [Department of Chemistry, Key Lab of Environment-Friendly Chemistry and Application in the Ministry of Education, Xiangtan University, Xiangtan 411105 (China); Cao, Yong, E-mail: yongcao@scut.edu.cn [Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology, Guangzhou 510640 (China)

    2014-02-14

    A novel tris(dibenzoylmethanato)[5-(2-(4-tert-butylbenzenyl)-5-benzenyl-1,3, 4-oxadiazole-4′)-1,10-phenanthroline]europium(III) [Eu(DBM){sub 3}(BuOXD-Phen)] containing an electron-transporting oxadiazole-functionalized phenanthroline ligand was synthesized and characterized. Its UV–vis absorption and photoluminescence (PL), as well as the electroluminescence (EL) in polymer light-emitting devices (PLEDs) were investigated. The double-layer PLEDs with a configuration of ITO/PEDOT:PSS (50 nm)/PVK (40 nm)/PFO:PBD (30%):Eu(DBM){sub 3}(BuOXD-Phen) (1–8 wt %) (80 nm)/Ba (4 nm)/Al (150 nm) were fabricated. Saturated red Eu{sup 3+} ion emission, based on the {sup 5}D{sub 0} → {sup 7}F{sub 2} transition, is centered at a wavelength of 614 nm with a full width at half maximum (FWHM) of 10 nm. The highest external quantum efficiency (QE{sub ext}) of 1.26% at current density of 1.65 mA cm{sup −2}, with a maximum brightness of 568 cd m{sup −2} at 137.8 mA cm{sup −2} was achieved from the device at 1 wt % dopant concentration. - Highlights: • An oxadiazole-functionalized europium(III) complex of Eu(DBM){sub 3}(BuOXD-Phen) was presented. • The optophysical properties of Eu(DBM){sub 3}(BuOXD-Phen) were investigated. • Saturated red emission was observed in the PLEDs. • An external quantum efficiency of 1.26% was obtained in these devices.

  8. Electron paramagnetic resonance and photoluminescence investigation of europium local structure in oxyfluoride glass ceramics containing SrF2 nanocrystals

    Science.gov (United States)

    Antuzevics, A.; Kemere, M.; Krieke, G.; Ignatans, R.

    2017-10-01

    Different compositions of europium doped aluminosilicate oxyfluoride glass ceramics prepared in air atmosphere have been studied by electron paramagnetic resonance (EPR) and optical spectroscopy methods. X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements show presence of homogenously distributed SrF2 nanocrystals after the heat treatment of the precursor glass. Efficient Eu3+ incorporation in the high symmetry environment of glass ceramics is observed from the photoluminescence spectra. EPR spectra indicate Eu3+ → Eu2+ reduction upon precipitation of crystalline phases in the glass matrix. For composition abundant with Eu2+ in the glassy state such behaviour is not detected. Local structure around europium ions is discussed based on differences in chemical compositions.

  9. Bright, highly water-soluble triazacyclononane europium complexes to detect ligand binding with time-resolved FRET microscopy.

    Science.gov (United States)

    Delbianco, Martina; Sadovnikova, Victoria; Bourrier, Emmanuel; Mathis, Gérard; Lamarque, Laurent; Zwier, Jurriaan M; Parker, David

    2014-09-26

    Luminescent europium complexes are used in a broad range of applications as a result of their particular emissive properties. The synthesis and application of bright, highly water-soluble, and negatively charged sulfonic- or carboxylic acid derivatives of para-substituted aryl-alkynyl triazacyclononane complexes are described. Introduction of the charged solubilizing moieties suppresses cellular uptake or adsorption to living cells making them applicable for labeling and performing assays on membrane receptors. These europium complexes are applied to monitor fluorescent ligand binding on cell-surface proteins with time-resolved Förster resonance energy transfer (TR-FRET) assays in plate-based format and using TR-FRET microscopy. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Optical and spectral studies on pure and europium doped olgite type Na(Sr,Ba)PO4 ceramics.

    Science.gov (United States)

    Jawaher, K Rackesh; Jagannathan, R; Das, S Jerome; Krishnan, S

    2015-04-05

    Europium ion doped olgite type Na(Sr,Ba)PO4 ceramics, a new generation of light emitting bulb, was prepared by a high temperature solid-state reaction method. The synthesized materials were subjected to various characterizations such as X-ray powder diffraction, Scanning electron microscopy and FT-IR spectra measurements. The EPR spectrum of the sample exhibits a well-resolved hyperfine structure of 151Eu2+ and 153Eu2+ isotopes and the g value has been calculated. Fluorescence spectra revealed that europium ions were present in divalent as well as in the trivalent oxidation states. The critical distance for energy transfer between Eu2+ and Eu2+ ion is calculated as 20Å, which is in good agreement with that of experimental data. The FTIR analysis reveals all the vibrations of PO4(3-) ions. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. A highly sensitive europium nanoparticle-based immunoassay for detection of influenza A/B virus antigen in clinical specimens.

    Science.gov (United States)

    Zhang, Panhe; Vemula, Sai Vikram; Zhao, Jiangqin; Du, Bingchen; Mohan, Haleyurgirisetty; Liu, Jikun; El Mubarak, Haja Sittana; Landry, Marie L; Hewlett, Indira

    2014-12-01

    We report the development of a novel europium nanoparticle-based immunoassay (ENIA) for rapid detection of influenza A and influenza B viruses. The ENIA demonstrated sensitivities of 90.7% (147/162) for influenza A viruses and 81.80% (9/11) for influenza B viruses compared to those for an in-house reverse transcription (RT)-PCR assay in testing of influenza-positive clinical samples. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  12. Semiconducting polymer dots doped with europium complexes showing ultranarrow emission and long luminescence lifetime for time-gated cellular imaging.

    Science.gov (United States)

    Sun, Wei; Yu, Jiangbo; Deng, Ruiping; Rong, Yu; Fujimoto, Bryant; Wu, Changfeng; Zhang, Hongjie; Chiu, Daniel T

    2013-10-18

    Bright dots: Semiconducting polymer dots (Pdots) doped with europium complexes possess line-like fluorescence emission, high quantum yield, and long fluorescence lifetime. The Pdots successfully labeled receptors on cells. The long fluorescence lifetime of the Pdots was used to distinguish them from other red fluorescence emitting nanoparticles, and improve the signal-to-noise ratio for time-gated cellular imaging. PVK=poly(9-vinylcarbazole). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Translocation and biokinetic behavior of nanoscaled europium oxide particles within 5 days following an acute inhalation in rats.

    Science.gov (United States)

    Creutzenberg, Otto; Kock, Heiko; Schaudien, Dirk

    2016-03-01

    Nanoscaled europium oxide (Eu2O3) particles were inhaled by rats after acute exposure and the potential translocation of particles followed by chemical analysis and transmission electron microscopy (TEM) was investigated. An aqueous dispersion (phosphate buffer/bovine serum albumin) of a commercially available Eu2O3 particle fraction consisting partially of nanoscaled particles was aerosolized with pressurized air. After rapid evaporation, rats inhaled the dry aerosol for 6 h in a single exposure resulting in an alveolar calculated dose of approximately 39.5 μg Eu2O3. Using chemical analysis, 36.8 μg Eu2O3 was detected 1 h after lung inhalation. The amount declined slightly to 34.5 μg after 1 day and 35.0 μg after 5 days. The liver showed an increase of Eu2O3 from 32.3 ng 1 h up to 294 ng 5 days after inhalation. Additionally, lung-associated lymph nodes, thymus, kidneys, heart and testis exhibited an increase of europium over the period investigated. In the blood, the highest amount of europium was found 1 h after treatment whereas feces, urine and mesenteric lymph nodes revealed the highest amount 1 day after treatment. Using TEM analysis, particles could be detected only in lungs, and in the liver, no particles were detectable. In conclusion, the translocation of Eu2O3 within 5 days following inhalation could be determined very precisely by chemical analysis. A translocation of Eu2O3 particulate matter to liver was not detectable by TEM analysis; thus, the overproportional level of 0.8% of the lung load observed in the liver after 5 days suggests a filtering effect of dissolved europium with accumulation. Copyright © 2015 John Wiley & Sons, Ltd.

  14. A Highly Sensitive Europium Nanoparticle-Based Immunoassay for Detection of Influenza A/B Virus Antigen in Clinical Specimens

    Science.gov (United States)

    Zhang, Panhe; Zhao, Jiangqin; Du, Bingchen; Mohan, Haleyurgirisetty; Liu, Jikun; El Mubarak, Haja Sittana; Landry, Marie L.

    2014-01-01

    We report the development of a novel europium nanoparticle-based immunoassay (ENIA) for rapid detection of influenza A and influenza B viruses. The ENIA demonstrated sensitivities of 90.7% (147/162) for influenza A viruses and 81.80% (9/11) for influenza B viruses compared to those for an in-house reverse transcription (RT)-PCR assay in testing of influenza-positive clinical samples. PMID:25297327

  15. Nature of the concentration thresholds of europium atom yield from the oxidized tungsten surface under electron stimulated desorption

    CERN Document Server

    Davydov, S Y

    2002-01-01

    The nature of the electron-stimulated desorption (ESD) of the europium atoms by the E sub e irradiating electrons energies, equal to 50 and 80 eV, as well as peculiarities of the Eu atoms yield dependence on their concentration on the oxidized tungsten surface are discussed. It is shown, that the ESD originates by the electron transition from the interval 5p- or 5s shell of the tungsten surface atom onto the oxygen external unfilled 2p-level

  16. Ultrasmall Superparamagnetic Iron Oxide Nanoparticles with Europium(III) DO3A as a Bimodal Imaging Probe.

    Science.gov (United States)

    Carron, Sophie; Bloemen, Maarten; Vander Elst, Luce; Laurent, Sophie; Verbiest, Thierry; Parac-Vogt, Tatjana N

    2016-03-18

    A new prototype consisting of ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles decorated with europium(III) ions encapsulated in a DO3A organic scaffold was designed as a platform for further development of bimodal contrast agents for MRI and optical imaging. The USPIO nanoparticles act as negative MRI contrast agents, whereas the europium(III) ion is a luminophore that is suitable for use in optical imaging detection. The functionalized USPIO nanoparticles were characterized by TEM, DLS, XRD, FTIR, and TXRF analysis, and a full investigation of the relaxometric and optical properties was conducted. The typical luminescence emission of europium(III) was observed and the main red emission wavelength was found at 614 nm. The relaxometric study of these ultrasmall nanoparticles showed r2 values of 114.8 mM(-1) Fes(-1) at 60 MHz, which is nearly double the r2 relaxivity of Sinerem(®). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. A lysosome targetable luminescent bioprobe based on a europium β-diketonate complex for cellular imaging applications.

    Science.gov (United States)

    George, T M; Krishna, Mahesh S; Reddy, M L P

    2016-11-22

    Herein, we report a novel lysosome targetable luminescent bioprobe derived from a europium coordination compound, namely Eu(pfphOCH3IN)3(DDXPO) 4 [where HpfphOCH3IN = 4,4,5,5,5-pentafluoro-3-hydroxy-1-(1-(4-methoxyphenyl)-1H-indol-3-yl)pent-2-en-1-one and DDXPO = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene oxide]. Notably, the newly designed europium complex exhibits significant quantum yield (Φoverall = 25 ± 3%) and 5D0 excited state lifetime (τ = 398 ± 3 μs) values under physiological pH (7.2) conditions when excited at 405 nm. Hence the developed europium complex has been evaluated for live cell imaging applications using mouse pre-adipocyte cell lines (3T3L1). Colocalization studies of the designed bio-probe with commercial Lysosome-GFP in 3T3L1 cells demonstrated the specific localization of the probe in the lysosome with a high colocalization coefficient (A = 0.83). Most importantly, the developed bioprobe exhibits good cell permeability, photostability and non-cytotoxicity.

  18. Mössbauer spectroscopy of europium-doped fluorochlorozirconate glasses and glass ceramics: optimization of storage phosphors in computed radiography.

    Science.gov (United States)

    Pfau, C; Paßlick, C; Gray, S K; Johnson, J A; Johnson, C E; Schweizer, S

    2013-05-22

    Eu(2+)-doped fluorochlorozirconate (FCZ) glasses and glass ceramics, which are being developed for medical and photovoltaic applications, have been analysed by Mössbauer spectroscopy. The oxidation state and chemical environment of the europium ions, which are important for the performance of these materials, were investigated. Routes for maximizing the divalent europium content were also investigated. By using EuCl2 instead of EuF2 in the starting material a fraction of about 90% of the europium was maintained in the Eu(2+) state as opposed to about 70% when using EuF2. The glass ceramics produced by subsequent thermal processing contain BaCl2 nanocrystals in which Eu(2+) is incorporated, as shown by the narrower linewidth in the Mössbauer spectrum. Debye temperatures of 147 K and 186 K for Eu(2+) and Eu(3+), respectively, were determined from temperature dependent Mössbauer measurements. The f-factors were used to obtain the Eu(2+)/Eu(3+) ratio from the area ratio of the corresponding absorption lines.

  19. Fast and Selective Preconcentration of Europium from Wastewater and Coal Soil by Graphene Oxide/Silane@Fe3O4 Dendritic Nanostructure.

    Science.gov (United States)

    Patra, Santanu; Roy, Ekta; Madhuri, Rashmi; Sharma, Prashant K

    2015-05-19

    In this study, nanocomposite of graphene oxide and silane modified magnetic nanoparticles (silane@Fe3O4) were synthesized in a form of dendritic structure. For this, silane@Fe3O4 nanoparticle gets sandwiched between two layers of graphene oxide by chemical synthesis route. The synthesized dendritic structure was used as a monomer for synthesis of europium ion imprinted polymer. The synthesis of imprinted polymer was contemplated onto the surface of the vinyl group modified silica fiber by activated generated free radical atom-transfer radical polymerization, that is, AGET-ATRP technique. The synthesized dendritic monomer was characterized by XRD, FT-IR, VSM, FE-SEM, and TEM analyses. The imprinted polymer modified silica fiber was first validated in the aqueous and blood samples for successful extraction and detection of europium ion with limit of detection = 0.050 pg mL(-1) (signal/noise = 3). The imprinted polymer modified silica fiber was also used for preconcentration and separation of europium metal ion from various soil samples of coal mine areas. However, the same silica fiber was also used for wastewater treatment and shows 100% performance for europium removal. The findings herein suggested that dendritic nanocomposite could be potentially used as a highly effective material for the enrichment and preconcentration of europium or other trivalent lanthanides/actinides in nuclear waste management.

  20. Development of europium doped core-shell silica cobalt ferrite functionalized nanoparticles for magnetic resonance imaging.

    Science.gov (United States)

    Kevadiya, Bhavesh D; Bade, Aditya N; Woldstad, Christopher; Edagwa, Benson J; McMillan, JoEllyn M; Sajja, Balasrinivasa R; Boska, Michael D; Gendelman, Howard E

    2017-02-01

    The size, shape and chemical composition of europium (Eu3+) cobalt ferrite (CFEu) nanoparticles were optimized for use as a "multimodal imaging nanoprobe" for combined fluorescence and magnetic resonance bioimaging. Doping Eu3+ ions into a CF structure imparts unique bioimaging and magnetic properties to the nanostructure that can be used for real-time screening of targeted nanoformulations for tissue biodistribution assessment. The CFEu nanoparticles (size ∼7.2nm) were prepared by solvothermal techniques and encapsulated into poloxamer 407-coated mesoporous silica (Si-P407) to form superparamagnetic monodisperse Si-CFEu nanoparticles with a size of ∼140nm. Folic acid (FA) nanoparticle decoration (FA-Si-CFEu, size ∼140nm) facilitated monocyte-derived macrophage (MDM) targeting. FA-Si-CFEu MDM uptake and retention was higher than seen with Si-CFEu nanoparticles. The transverse relaxivity of both Si-CFEu and FA-Si-CFEu particles were r2=433.42mM-1s-1 and r2=419.52mM-1s-1 (in saline) and r2=736.57mM-1s-1 and r2=814.41mM-1s-1 (in MDM), respectively. The results were greater than a log order-of-magnitude than what was observed at replicate iron concentrations for ultrasmall superparamagnetic iron oxide (USPIO) particles (r2=31.15mM-1s-1 in saline) and paralleled data sets obtained for T2 magnetic resonance imaging. We now provide a developmental opportunity to employ these novel particles for theranostic drug distribution and efficacy evaluations. A novel europium (Eu3+) doped cobalt ferrite (Si-CFEu) nanoparticle was produced for use as a bioimaging probe. Its notable multifunctional, fluorescence and imaging properties, allows rapid screening of future drug biodistribution. Decoration of the Si-CFEu particles with folic acid increased its sensitivity and specificity for magnetic resonance imaging over a more conventional ultrasmall superparamagnetic iron oxide particles. The future use of these particles in theranostic tests will serve as a platform for

  1. Tuning Eu{sup 3+} emission in europium sesquioxide films by changing the crystalline phase

    Energy Technology Data Exchange (ETDEWEB)

    Mariscal, A., E-mail: antonio.mariscal@csic.es [Laser Processing Group, Instituto de Óptica, CSIC, C/ Serrano 121, 28006 Madrid (Spain); Quesada, A. [Ceramics for Smart Systems Group, Instituto de Cerámica y Vidrio, C/ Kelsen 5, 28049 Madrid (Spain); Camps, I. [Laser Processing Group, Instituto de Óptica, CSIC, C/ Serrano 121, 28006 Madrid (Spain); Palomares, F.J. [Instituto de Ciencia de Materiales de Madrid, C/ Sor Juana Inés de la Cruz 3, 28049 Madrid (Spain); Fernández, J.F. [Ceramics for Smart Systems Group, Instituto de Cerámica y Vidrio, C/ Kelsen 5, 28049 Madrid (Spain); Serna, R. [Laser Processing Group, Instituto de Óptica, CSIC, C/ Serrano 121, 28006 Madrid (Spain)

    2016-06-30

    Highlights: • PLD production of high quality europium sesquioxide (Eu{sub 2}O{sub 3}) films. • The deposition of Al{sub 2}O{sub 3} capping and/or buffer layers modifies the crystallization for Eu{sub 2}O{sub 3} films upon annealing. • The formation of cubic or monoclinic phases can be favored. • Eu{sup 3+} emission tuning is achieved as a consequence of crystal field effects. - Abstract: We report the growth of europium sesquioxide (Eu{sub 2}O{sub 3}) thin films by pulsed laser deposition (PLD) in vacuum at room temperature from a pure Eu{sub 2}O{sub 3} ceramic bulk target. The films were deposited in different configurations formed by adding capping and/or buffer layers of amorphous aluminum oxide (a-Al{sub 2}O{sub 3}). The optical properties, refractive index and extinction coefficient of the as deposited Eu{sub 2}O{sub 3} layers were obtained. X-ray photoelectron spectroscopy (XPS) measurements were done to assess its chemical composition. Post-deposition annealing was performed at 500 °C and 850 °C in air in order to achieve the formation of crystalline films and to accomplish photoluminescence emission. According to the analysis of X-ray diffraction (XRD) spectra, cubic and monoclinic phases were formed. It is found that the relative amount of the phases is related to the different film configurations, showing that the control over the crystallization phase can be realized by adequately designing the structures. All the films showed photoluminescence emission peaks (under excitation at 355 nm) that are attributed to the intra 4f-transitions of Eu{sup 3+} ions. The emission spectral shape depends on the crystalline phase of the Eu{sub 2}O{sub 3} layer. Specifically, changes in the hypersensitive {sup 5}D{sub 0} → {sup 7}F{sub 2} emission confirm the strong influence of the crystal field effect on the Eu{sup 3+} energy levels.

  2. Highly efficient precipitation of phosphoproteins using trivalent europium, terbium, and erbium ions

    Energy Technology Data Exchange (ETDEWEB)

    Guezel, Yueksel; Rainer, Matthias; Mirza, Munazza Raza; Bonn, Guenther K. [Leopold-Franzens University, Institute of Analytical Chemistry and Radiochemistry, Innsbruck (Austria)

    2012-05-15

    This study describes a highly efficient method for the selective precipitation of phosphoproteins by trivalent europium, terbium, and erbium metal ions. These metal cations belong to the group of lanthanides and are known to be hard acceptors with an overwhelming preference for oxygen-containing anions such as phosphates to which they form very tight ionic bonds. The method could be successfully applied to specifically precipitate phosphoproteins from complex samples including milk and egg white by forming solid metal-protein complexes. Owing to the low solubility product of the investigated lanthanide salts, the produced metal-protein complexes showed high stability. The protein pellets were extensively washed to remove nonphosphorylated proteins and contaminants. For the analysis of proteins the pellets were first dissolved in 30 % formic acid and subjected to matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS. For peptide mass-fingerprint analysis the precipitated phosphoproteins were enzymatically digested using microwave-assisted digestion. The method was found to be highly specific for the isolation and purification of phosphoproteins. Protein quantification was performed by colorimetric detection of total precipitated phosphoproteins and revealed more than 95 % protein recovery for each lanthanide salt. (orig.)

  3. Effects of europium polyoxometalate encapsulated in silica nanoparticles (nanocarriers) in soil invertebrates

    Science.gov (United States)

    Bicho, Rita C.; Soares, Amadeu M. V. M.; Nogueira, Helena I. S.; Amorim, Mónica J. B.

    2016-12-01

    Polyoxometalates (POMs) are metal oxo clusters that have been investigated for several applications in material sciences, catalysis, and biomedicine; these gained increasing interest in the field of nanotechnology as nanocarriers for drug delivery. Associated to the increasing applications, there is the need for information regarding the effects on the environment of these compounds, which is completely absent in the literature. In the present study, the effects of europium polyoxometalates encapsulated into silica nanoparticles (Eu-POM/SiO2 NPs) were assessed on the soil representative Enchytraeus crypticus. The individual materials were also assessed (Eu-POMs and SiO2 NPs). Toxicity was evaluated in various test media with increasing complexity: water, soil/water extracts, and soil. Toxicity was only observed for Eu-POM/SiO2 NPs and in the presence of soil components. Despite the fact that effects were observed for concentrations higher than current predicted environmental concentration (PEC), attention should be given to the growing use of these compounds. The present study shows the importance of assessing the effects in soil media, also compared to water. Moreover, results of "no effect" are critically needed and often unpublished. The present study can contribute to the improvement of the OECD guidelines for safety of manufactured nanomaterials on environmental toxicity in the soil compartment providing an improved test alternative.

  4. Spectral Interferences Manganese (Mn) - Europium (Eu) Lines in X-Ray Fluorescence Spectrometry Spectrum

    Science.gov (United States)

    Tanc, Beril; Kaya, Mustafa; Gumus, Lokman; Kumral, Mustafa

    2016-04-01

    X-ray fluorescence (XRF) spectrometry is widely used for quantitative and semi quantitative analysis of many major, minor and trace elements in geological samples. Some advantages of the XRF method are; non-destructive sample preparation, applicability for powder, solid, paste and liquid samples and simple spectrum that are independent from chemical state. On the other hand, there are some disadvantages of the XRF methods such as poor sensitivity for low atomic number elements, matrix effect (physical matrix effects, such as fine versus course grain materials, may impact XRF performance) and interference effect (the spectral lines of elements may overlap distorting results for one or more elements). Especially, spectral interferences are very significant factors for accurate results. In this study, semi-quantitative analyzed manganese (II) oxide (MnO, 99.99%) was examined. Samples were pelleted and analyzed with XRF spectrometry (Bruker S8 Tiger). Unexpected peaks were obtained at the side of the major Mn peaks. Although sample does not contain Eu element, in results 0,3% Eu2O3 was observed. These result can occur high concentration of MnO and proximity of Mn and Eu lines. It can be eliminated by using correction equation or Mn concentration can confirm with other methods (such as Atomic absorption spectroscopy). Keywords: Spectral Interferences; Manganese (Mn); Europium (Eu); X-Ray Fluorescence Spectrometry Spectrum.

  5. Performance of fluorescent europium(III) nanoparticles and colloidal gold reporters in lateral flow bioaffinity assay.

    Science.gov (United States)

    Juntunen, Etvi; Myyryläinen, Tiina; Salminen, Teppo; Soukka, Tero; Pettersson, Kim

    2012-09-01

    Lateral flow (LF) immunoassays (i.e., immunochromatographic assays) have traditionally been applied to analytes that do not require very high analytical sensitivity or quantitative results. The selection of potential analytes is often limited by the performance characteristics of the assay technology. Analytes with more demanding sensitivity requirements call for reporter systems enabling high analytical sensitivity. In this study, we systematically compared the performance of fluorescent europium(III) [Eu(III)] chelate dyed polystyrene nanoparticles and colloidal gold particles in lateral flow assays. The effect of time-resolved measurement mode was also studied. Because binder molecules used in immunoassays might not behave similarly when conjugated to different reporter particles, two model assays were constructed to provide reliable technical comparison of the two reporter systems. The comparative experiment demonstrated that the fluorescent nanoparticles yielded 7- and 300-fold better sensitivity compared with colloidal gold in the two test systems, respectively. Although the two reporter particles may induce variable effects using individual binders, overall the high specific activity of Eu(III) nanoparticles has superior potential over colloidal gold particles for the development of robust high-sensitivity bioaffinity assays. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Carbon nanotube-loaded Nafion film electrochemical sensor for metal ions: europium.

    Science.gov (United States)

    Wang, Tingting; Zhao, Daoli; Guo, Xuefei; Correa, Jaime; Riehl, Bill L; Heineman, William R

    2014-05-06

    A Nafion film loaded with novel catalyst-free multiwalled carbon nanotubes (MWCNTs) was used to modify a glassy carbon (GC) electrode to detect trace concentrations of metal ions, with europium ion (Eu(3+)) as a model. The interaction between the sidewalls of MWCNTs and the hydrophobic backbone of Nafion allows the MWCNTs to be dispersed in Nafion, which was then coated as a thin film on the GC electrode surface. The electrochemical response to Eu(3+) was found to be ∼10 times improved by MWCNT concentrations between 0.5 and 2 mg/mL, which effectively expanded the electrode surface into the Nafion film and thereby reduced the diffusion distance of Eu(3+) to the electrode surface. At low MWCNT concentrations of 0.25 and 0.5 mg/mL, no significant improvement in signal was obtained compared with Nafion alone. Scanning electron microscopy and electrochemical impedance spectroscopy were used to characterize the structure of the MWCNT-Nafion film, followed by electrochemical characterization with Eu(3+) via cyclic voltammetry and preconcentration voltammetry. Under the optimized conditions, a linear range of 1-100 nM with a calculated detection limit of 0.37 nM (signal/noise = 3) was obtained for determination of Eu(3+) by Osteryoung square-wave voltammetry after a preconcentration time of 480 s.

  7. Effects of europium polyoxometalate encapsulated in silica nanoparticles (nanocarriers) in soil invertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Bicho, Rita C., E-mail: ritabicho@ua.pt; Soares, Amadeu M.V.M. [Universidade de Aveiro, Departamento de Biologia & CESAM (Portugal); Nogueira, Helena I.S. [Universidade de Aveiro, Departamento de Química & CICECO (Portugal); Amorim, Mónica J.B. [Universidade de Aveiro, Departamento de Biologia & CESAM (Portugal)

    2016-12-15

    Polyoxometalates (POMs) are metal oxo clusters that have been investigated for several applications in material sciences, catalysis, and biomedicine; these gained increasing interest in the field of nanotechnology as nanocarriers for drug delivery. Associated to the increasing applications, there is the need for information regarding the effects on the environment of these compounds, which is completely absent in the literature. In the present study, the effects of europium polyoxometalates encapsulated into silica nanoparticles (Eu-POM/SiO{sub 2} NPs) were assessed on the soil representative Enchytraeus crypticus. The individual materials were also assessed (Eu-POMs and SiO{sub 2} NPs). Toxicity was evaluated in various test media with increasing complexity: water, soil/water extracts, and soil. Toxicity was only observed for Eu-POM/SiO{sub 2} NPs and in the presence of soil components. Despite the fact that effects were observed for concentrations higher than current predicted environmental concentration (PEC), attention should be given to the growing use of these compounds. The present study shows the importance of assessing the effects in soil media, also compared to water. Moreover, results of “no effect” are critically needed and often unpublished. The present study can contribute to the improvement of the OECD guidelines for safety of manufactured nanomaterials on environmental toxicity in the soil compartment providing an improved test alternative.

  8. EUROPIUM ION INFLUENCE ON THE FORMATION OF Ag-NANOPARTICLES IN FLUORINE PHOSPHATE GLASSES

    Directory of Open Access Journals (Sweden)

    R. O. Pysh'ev

    2015-05-01

    Full Text Available The paper deals with research of formation characteristics of silver nanoparticles in fluorophosphate glasses 0.25 Na2O - 0.5 P2O5 - 0.10 Ga2O3 - 0.075 AlF3 - 0.025 NaF - 0.05 ZnF2 doped with EuF3 (0.8 and 4 wt.% and without them. The synthesis was carried out in closed glassy carbon crucibles in argon atmosphere. Nanoparticles were formed after a low temperature process of Ag+ → Na+ ion-exchange (320 °C and subsequent heat treatment. It was shown that in the initial glasses doped with EuF3, rare earth ions exist in two valence forms (Eu2+ and Eu3+ in dynamic equilibrium and the concentration of Eu2+ increases proportionally to the total concentration of fluoride. It was shown that sizes of molecular clusters or metal nanoparticles depend on the concentration of europium fluoride and duration of ion exchange. The metallic Ag-nanoparticles sizes were defined for different times of heat treatment and ion exchange. The possibility of the stimulating growth of nanoparticles through the introduction of additional EuF3 in the glass was proved. The possibility of obtaining nanoparticles without the heat treatment in glasses with a high concentration of EuF3 was shown. Chemical mechanism for the formation of Ag-nanoparticles during the ion exchange was suggested.

  9. Nanoparticles in the zirconia-europium niobate system via hydrothermal route.

    Science.gov (United States)

    Hirano, Masanori; Dozono, Hayato

    2013-10-01

    The effect of the composition on the hydrothermal formation, structure, and properties of nanocrystalline luminescent materials in the zirconia (ZrO2)-europium niobate 1/4(Eu3NbO7) system was investigated. In the composition range 40 particles with crystallite size 6.0-7.6 nm that were hydrothermally formed from the precursor solutions of NbCl5, ZrOCI2, and EuCl3 under weakly basic conditions at 240 degrees C showed cubic structure. The lattice parameter when estimated as a single cubic phase linearly decreased as the concentration of ZrO2 increased. The presence of zirconia component effectively promoted the formation of nanocrystals containing the niobate, Eu3NbO7 under hydrothermal condition. The nanocrystalline particles could be excited by ultraviolet light 395 nm (f-f transition) and emitted orange (590 nm) and red light (610 nm) corresponding to 5D0 --> 7F1 and 5D0 --> 7F2 transitions of Eu3+, respectively. The intensity of the electric dipole transition (5D0 --> 7F2) that was expressed in values relative to the magnetic dipole transition (5D0 --> 7F1) increased with increased heat-treatment temperature in the range from 950 to 1200 degrees C.

  10. Photoluminescence of monocrystalline and stain-etched porous silicon doped with high temperature annealed europium

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero-Lemus, R; Montesdeoca-Santana, A; Gonzalez-Diaz, B; Diaz-Herrera, B; Hernandez-Rodriguez, C; Jimenez-Rodriguez, E [Departamento de Fisica Basica, Universidad de La Laguna (ULL), Avenida AstrofIsico Francisco Sanchez, 2. 38206 La Laguna, Tenerife (Spain); Velazquez, J J, E-mail: rglemus@ull.es [Departamento de Fisica Fundamental y Experimental, Electronica y Sistemas, Universidad de La Laguna (ULL), Avenida Astrofisico Francisco Sanchez, 2. 38206 La Laguna, Tenerife (Spain)

    2011-08-24

    In this work, for the first time, the photoluminescent emission and excitation spectra of non-textured layers and stain-etched porous silicon layers (PSLs) doped with high temperature annealed europium (Eu) are evaluated. The PSLs are evaluated as a host for rare earth ions and as an antireflection coating. The applied doping process, which consists in a simple impregnation method followed by a high-temperature annealing step, is compatible with the standard processes in the fabrication of solar cells. The results show down-shifting processes with a maximum photoluminescent intensity at 615 nm, related to the transition {sup 5}D{sub 0} {yields} {sup 7}F{sub 2}. Different initial concentrations of Eu(NO{sub 3}){sub 3} are evaluated to study the influence of the rare earth concentration on the photoluminescent intensity. The chemical composition and the morphology of Eu-doped PSLs are examined by means of x-ray dispersion spectroscopy, Fourier-transform infrared spectroscopy and scanning electron microscopy. These Eu-doped layers are considered to be applied as energy converters in silicon-based third generation solar cells.

  11. Europium (III) and Uranium (VI) complexation by natural organic matter (NOM): Effect of source.

    Science.gov (United States)

    Kautenburger, Ralf; Sander, Jonas M; Hein, Christina

    2017-03-01

    For the safe long-term storage of high-level radioactive waste (HLW), detailed information about geo-chemical behavior of radioactive and toxic metal ions under environmental conditions is important. Natural organic matter (NOM) can play a crucial role in the immobilization or mobilization of these metal ions due to its complexation and colloid formation tendency. In this study, the complexation of europium (as chemical homologue of trivalent actinides such as americium) and uranium (as main component of HLW) by ten humic acids (HA) from different sources and Suwannee NOM river extract has been analyzed. Capillary electrophoresis in combination with inductively coupled plasma mass spectrometry has been used for the evaluation of complex stability constants log β. In order to determine the complex stability constants a conservative single site model was used in this study. In dependence of their source and thus of NOM structure the log β values for the analyzed humic acids are in the range of 6.1-7.0 for Eu(III) and 5.2-6.4 for U(VI) (UO 2 2+ ), respectively. In contrast to the results for HA the used Suwannee river NOM reveals log β values in the range of nearly two orders of magnitude lower (4.6 for Eu 3+ and 4.5 for UO 2 2+ ) under the geochemical conditions applied in this study. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Europium incorporated into titanium oxide by the sol-gel method

    Directory of Open Access Journals (Sweden)

    Lucas Alonso Rocha

    2005-09-01

    Full Text Available In this work titanium sol was prepared from tetraethylorthotitanate (TEOT in ethanol, stabilized with beta-diketonate 2,4 pentanedione in molar ratio 1:1 homogenized by magnetic stirring, europium ion was add as structural probe. The xerogels were heat treated at 500, 750 and 1000 °C and the characterization was realized by x-ray diffraction (XRD, transmission electron microscopy (TEM, thermogravimetric analysis (TGA/DSC and photoluminescence (PL. The excitation spectra of Eu (III ion present maximum in 394 nm correspondent to 5L6 level and emission spectra present bands characteristic transitions arising from the 5 D0 -> 7F J (J = 0, 1, 2, 3, 4 manifolds to samples treat at 500 and 750 °C. The Eu (III emission disappear, when heated at 1000 °C, probably due to phase transition anatase to rutile and migrations of ions to the external surface that was proved by x-ray diffraction, transmission electronic microscopy and the thermogravimetric analyses of xerogels.

  13. Luminescence studies on the europium doped strontium metasilicate phosphor prepared by solid state reaction method

    Directory of Open Access Journals (Sweden)

    Ishwar Prasad Sahu

    2017-03-01

    Full Text Available Europium doped strontium meta-silicate (namely SrSiO3:Eu3+ phosphor was prepared by a high temperature solid state reaction method. The sintered SrSiO3:Eu3+ phosphor possesses a monoclinic structure by the XRD. Energy dispersive X-ray spectrum (EDS confirms the presence of elements in the desired sample. Thermoluminescence (TL kinetic parameters such as activation energy (E, order of kinetics (b, and frequency factor (s were calculated by the peak shape method. The orange–red emission was shown to originate from the 5D0–7FJ (J = 0, 1, 2, 3, 4 transitions of Eu3+ ions as the sample was excited at 396 nm. The SrSiO3:Eu3+ phosphor with almost pure orange-red color purity (99.62% shows the quantum efficiency of 10.2% (excited by 396 nm, which is higher than those of commercial red phosphors Y2O3:Eu3+ and Y2O2S:Eu3+ with quantum efficiencies of 9.6% (excited by 394 nm and 4.2% (excited by 395 nm, respectively. Mechanoluminescence (ML intensity of the SrSiO3:Eu3+ phosphor was also found to increase linearly with increasing the impact velocity of the moving piston, suggesting that the discussed phosphor can be used as a stress sensor.

  14. Europium Luminescence Used for Logic Gate and Ions Sensing with Enoxacin As the Antenna.

    Science.gov (United States)

    Lu, Lixia; Chen, Chuanxia; Zhao, Dan; Sun, Jian; Yang, Xiurong

    2016-01-19

    Luminescent lanthanide ion complexes have received increasing attention because of their unique optical properties. Herein, we discovered that the luminescence of europium(III) (Eu(3+)) could be regulated by Ag(+) and SCN(-) in seconds with enoxacin (ENX) as the antenna. Under given conditions, only the simultaneous introduction of Ag(+) and SCN(-) could remarkably enhance the luminescence intensity of Eu(3+)-ENX complexes. This phenomenon has been exploited to design an "AND" logic gate and specific luminescence turn-on assays for sensitively sensing Ag(+) and SCN(-) for the first time. Furthermore, the addition of S(2-) resulted in efficient luminescence quenching of the Eu(3+)/ENX/Ag(+)/SCN(-) system due to the strong affinity between Ag(+) and S(2-). Thus, a new luminescent sensing platform for S(2-) was established, which exhibited excellent selectivity and high sensitivity. S(2-) could be detected within the concentration range of 100 nM to 12.5 μM with a detection limit of 60 nM. Such sensing system features simplicity, rapidity, and flexibility. Moreover, this proposed Eu(3+)-based luminescent assay could be successfully applied in the real environmental water sample analysis.

  15. Radiation effects on beta 10.6 of pure and europium doped KCl

    Science.gov (United States)

    Grimes, H. H.; Maisel, J. E.; Hartford, R. H.

    1975-01-01

    Changes in the optical absorption coefficient as a result of X-ray and electron bombardment of pure KCl (monocrystalline and polycrystalline), and divalent europium doped polycrystalline KCl were determined. The optical absorption coefficients were measured by a constant heat flow calorimetric method. Both 300 KV X-irradiation and 2 MeV electron irradiation produced significant increases in beta 10.6, measured at room temperature. The X-irradiation of pure moncrystalline KCl increased beta 10.6 by 0.005/cm for a 113 MR dose. For an equivalent dose, 2 MeV electrons were found less efficient in changing beta 10.6. However, electron irradiation of pure and Eu-doped polycrystalline KCl produced marked increases in adsorption. Beta increased to over 0.25/cm in Eu-doped material for a 30 x 10 to the 14th power electrons/sq cm dose, a factor of 20 increase over unirradiated material. Moreover, bleaching the electron irradiated doped KCl with 649 m light produced and additional factor of 1.5 increase. These findings will be discussed in light of known defect-center properties in KCl.

  16. Accelerating the clearance of mutant huntingtin protein aggregates through autophagy induction by europium hydroxide nanorods.

    Science.gov (United States)

    Wei, Peng-Fei; Zhang, Li; Nethi, Susheel Kumar; Barui, Ayan Kumar; Lin, Jun; Zhou, Wei; Shen, Yi; Man, Na; Zhang, Yun-Jiao; Xu, Jing; Patra, Chitta Ranjan; Wen, Long-Ping

    2014-01-01

    Autophagy is one of the well-known pathways to accelerate the clearance of protein aggregates, which contributes to the therapy of neurodegenerative diseases. Although there are numerous reports that demonstrate the induction of autophagy with small molecules including rapamycin, trehalose and lithium, however, there are few reports mentioning the clearance of aggregate-prone proteins through autophagy induction by nanoparticles. In the present article, we have demonstrated that europium hydroxide [Eu(III)(OH)3] nanorods can reduce huntingtin protein aggregation (EGFP-tagged huntingtin protein with 74 polyQ repeats), responsible for neurodegenerative diseases. Again, we have found that these nanorods induce authentic autophagy flux in different cell lines (Neuro 2a, PC12 and HeLa cells) through the expression of higher levels of characteristic autophagy marker protein LC3-II and degradation of selective autophagy substrate/cargo receptor p62/SQSTM1. Furthermore, depression of protein aggregation clearance through the autophagy blockade has also been observed by using specific inhibitors (wortmannin and chloroquine), indicating that autophagy is involved in the degradation of huntingtin protein aggregation. Since [Eu(III)(OH)3] nanorods can enhance the degradation of huntingtin protein aggregation via autophagy induction, we strongly believe that these nanorods would be useful for the development of therapeutic treatment strategies for various neurodegenerative diseases in near future using nanomedicine approach. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. High-resolution Thermal Micro-imaging Using Europium Chelate Luminescent Coatings.

    Science.gov (United States)

    Benseman, Timothy M; Hao, Yang; Vlasko-Vlasov, Vitalii K; Welp, Ulrich; Koshelev, Alexei E; Kwok, Wai-Kwong; Divan, Ralu; Keiser, Courtney; Watanabe, Chiharu; Kadowaki, Kazuo

    2017-04-16

    Micro-electronic devices often undergo significant self-heating when biased to their typical operating conditions. This paper describes a convenient optical micro-imaging technique which can be used to map and quantify such behavior. Europium thenoyltrifluoroacetonate (EuTFC) has a 612 nm luminescence line whose activation efficiency drops strongly with increasing temperature, due to T-dependent interactions between the Eu3+ ion and the organic chelating compound. This material may be readily coated on to a sample surface by thermal sublimation in vacuum. When the coating is excited with ultraviolet light (337 nm) an optical micro-image of the 612 nm luminescent response can be converted directly into a map of the sample surface temperature. This technique offers spatial resolution limited only by the microscope optics (about 1 micron) and time resolution limited by the speed of the camera employed. It offers the additional advantages of only requiring comparatively simple and non-specialized equipment, and giving a quantitative probe of sample temperature.

  18. In vivo synthesis of europium selenide nanoparticles and related cytotoxicity evaluation of human cells.

    Science.gov (United States)

    Kim, Eun Bee; Seo, Ji Min; Kim, Gi Wook; Lee, Sang Yup; Park, Tae Jung

    2016-12-01

    Nanotechnology strives to combine new materials for development of noble nanoparticles. As the nanoparticles exhibit unique optical, electronic, and magnetic properties depending on their composition, developing safe, cost-effective and environmentally friendly technologies for the synthesis have become an important issue. In this study, in vivo synthesis of europium selenide (EuSe) nanoparticles was performed using recombinant Escherichia coli cells expressing heavy-metal binding proteins, phytochelatin synthase and metallothionein. The formation of EuSe nanoparticles was confirmed by using UV-vis spectroscopy, spectrofluorometry, X-ray diffraction, energy dispersive X-ray and transmission electron microscopy. The synthesized EuSe nanoparticles exhibited high fluorescence intensities as well as strong magnetic properties. Furthermore, anti-cancer effect of EuSe nanoparticles against cancer cell lines was investigated. This strategy for the biogenic synthesis of nanoparticles has a great potential as bioimaging tools and drug carrying agents in biomedical fields due to its simplicity and nontoxicity. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Circularly Polarized Luminescence in Enantiopure Europium and Terbium Complexes with Modular, All-Oxygen Donor Ligands

    Science.gov (United States)

    Seitz, Michael; Do, King; Ingram, Andrew J.; Moore, Evan G.; Muller, Gilles; Raymond, Kenneth N.

    2009-01-01

    Abstract: Circulaly polarized luminescence from terbium(III) complexed and excited by chiral antenna ligands gives strong emission The modular synthesis of three new octadentate, enantiopure ligands are reported - one with the bidentate chelating unit 2-hydroxyisophthalamide (IAM) and two with 1-hydroxy-2-pyridinone (1,2-HOPO) units. A new design principle is introduced for the chiral, non-racemic hexamines which constitute the central backbones for the presented class of ligands. The terbium(III) complex of the IAM ligand, as well as the europium(III) complexes of the 1,2-HOPO ligands are synthesized and characterized by various techniques (NMR, UV, CD, luminescence spectroscopy). All species exhibit excellent stability and moderate to high luminescence efficiency (quantum yields ΦEu = 0.05–0.08 and ΦTb = 0.30–0.57) in aqueous solution at physiological pH. Special focus is put onto the properties of the complexes in regard to circularly polarized luminescence (CPL). The maximum luminescence dissymmetry factors (glum) in aqueous solution are high with |glum|max = 0.08 – 0.40. Together with the very favorable general properties (good stability, high quantum yields, long lifetimes), the presented lanthanide complexes can be considered as good candidates for analytical probes based on CPL in biologically relevant environments. PMID:19639983

  20. Complexation and molecular modeling studies of europium(III)-gallic acid-amino acid complexes.

    Science.gov (United States)

    Taha, Mohamed; Khan, Imran; Coutinho, João A P

    2016-04-01

    With many metal-based drugs extensively used today in the treatment of cancer, attention has focused on the development of new coordination compounds with antitumor activity with europium(III) complexes recently introduced as novel anticancer drugs. The aim of this work is to design new Eu(III) complexes with gallic acid, an antioxida'nt phenolic compound. Gallic acid was chosen because it shows anticancer activity without harming health cells. As antioxidant, it helps to protect human cells against oxidative damage that implicated in DNA damage, cancer, and accelerated cell aging. In this work, the formation of binary and ternary complexes of Eu(III) with gallic acid, primary ligand, and amino acids alanine, leucine, isoleucine, and tryptophan was studied by glass electrode potentiometry in aqueous solution containing 0.1M NaNO3 at (298.2 ± 0.1) K. Their overall stability constants were evaluated and the concentration distributions of the complex species in solution were calculated. The protonation constants of gallic acid and amino acids were also determined at our experimental conditions and compared with those predicted by using conductor-like screening model for realistic solvation (COSMO-RS) model. The geometries of Eu(III)-gallic acid complexes were characterized by the density functional theory (DFT). The spectroscopic UV-visible and photoluminescence measurements are carried out to confirm the formation of Eu(III)-gallic acid complexes in aqueous solutions. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Luminescent single-walled carbon nanotube-sensitized europium nanoprobes for cellular imaging

    Science.gov (United States)

    Avti, Pramod K; Sitharaman, Balaji

    2012-01-01

    Lanthanoid-based optical probes with excitation wavelengths in the ultra-violet (UV) range (300–325 nm) have been widely developed as imaging probes. Efficient cellular imaging requires that lanthanoid optical probes be excited at visible wavelengths, to avoid UV damage to cells. The efficacy of europium-catalyzed single-walled carbon nanotubes (Eu-SWCNTs), as visible nanoprobes for cellular imaging, is reported in this study. Confocal fluorescence microscopy images of breast cancer cells (SK-BR-3 and MCF-7) and normal cells (NIH 3T3), treated with Eu-SWCNT at 0.2 μg/mL concentration, showed bright red luminescence after excitation at 365 nm and 458 nm wavelengths. Cell viability analysis showed no cytotoxic effects after the incubation of cells with Eu-SWCNTs at this concentration. Eu-SWCNT uptake is via the endocytosis mechanism. Labeling efficiency, defined as the percentage of incubated cells that uptake Eu-SWCNT, was 95%–100% for all cell types. The average cellular uptake concentration was 6.68 ng Eu per cell. Intracellular localization was further corroborated by transmission electron microscopy and Raman microscopy. The results indicate that Eu-SWCNT shows potential as a novel cellular imaging probe, wherein SWCNT sensitizes Eu3+ ions to allow excitation at visible wavelengths, and stable time-resolved red emission. The ability to functionalize biomolecules on the exterior surface of Eu-SWCNT makes it an excellent candidate for targeted cellular imaging. PMID:22619533

  2. Europium(III) DOTA-derivatives having ketone donor pendant arms display dramatically slower water exchange

    Science.gov (United States)

    Green, Kayla N.; Viswanathan, Subha; Rojas-Quijano, Federico A.; Kovacs, Zoltan; Sherry, A. Dean

    2011-01-01

    A series of new 1,4,7,10-tetraazacyclododecane-derivatives having a combination of amide and ketone donor groups as side-arms were prepared and their complexes with europium(III) studied in detail by high resolution NMR spectroscopy. The chemical shift of the Eu3+-bound water resonance, the chemical exchange saturation transfer (CEST) characteristics of the complexes, and the bound water residence lifetimes (τm) were found to vary dramatically with the chemical structure of the side-arms. Substitution of ketone oxygen donor atoms for amide oxygen donor atoms resulted in an increase in residence water lifetimes (τm) and a decrease in chemical shift of the Eu3+-bound water molecule (Δω). These experimental results along with density functional theory (DFT) calculations demonstrate that introduction of weakly donating oxygen atoms in these complexes results in a much weaker ligand field, more positive charge on the Eu3+ ion and an increased water residence lifetime as expected for a dissociative mechanism. These results provide new insights into the design of paramagnetic CEST agents with even slower water exchange kinetics that will make them more efficient for in vivo imaging applications. PMID:21306137

  3. Urinary monitoring of exposure to yttrium, scandium, and europium in male Wistar rats.

    Science.gov (United States)

    Kitamura, Yasuhiro; Usuda, Kan; Shimizu, Hiroyasu; Fujimoto, Keiichi; Kono, Rei; Fujita, Aiko; Kono, Koichi

    2012-12-01

    On the assumption that rare earth elements (REEs) are nontoxic, they are being utilized as replacements of toxic heavy metals in novel technological applications. However, REEs are not entirely innocuous, and their impact on health is still uncertain. In the past decade, our laboratory has studied the urinary excretion of REEs in male Wistar rats given chlorides of europium, scandium, and yttrium solutions by one-shot intraperitoneal injection or oral dose. The present paper describes three experiments for the suitability and appropriateness of a method to use urine for biological monitoring of exposure to these REEs. The concentrations of REEs were determined in cumulative urine samples taken at 0-24 h by inductively coupled plasma atomic emission spectroscopy, showing that the urinary excretion of REEs is <2 %. Rare earth elements form colloidal conjugates in the bloodstream, which make high REEs accumulation in the reticuloendothelial system and glomeruli and low urinary excretion. The high sensitivity of inductively coupled plasma-argon emission spectrometry analytical methods, with detection limits of <2 μg/L, makes urine a comprehensive assessment tool that reflects REE exposure. The analytical method and animal experimental model described in this study will be of great importance and encourage further discussion for future studies.

  4. Europium Luminescence: Electronic Densities and Superdelocalizabilities for a Unique Adjustment of Theoretical Intensity Parameters

    Science.gov (United States)

    Dutra, José Diogo L.; Lima, Nathalia B. D.; Freire, Ricardo O.; Simas, Alfredo M.

    2015-09-01

    We advance the concept that the charge factors of the simple overlap model and the polarizabilities of Judd-Ofelt theory for the luminescence of europium complexes can be effectively and uniquely modeled by perturbation theory on the semiempirical electronic wave function of the complex. With only three adjustable constants, we introduce expressions that relate: (i) the charge factors to electronic densities, and (ii) the polarizabilities to superdelocalizabilities that we derived specifically for this purpose. The three constants are then adjusted iteratively until the calculated intensity parameters, corresponding to the 5D0→7F2 and 5D0→7F4 transitions, converge to the experimentally determined ones. This adjustment yields a single unique set of only three constants per complex and semiempirical model used. From these constants, we then define a binary outcome acceptance attribute for the adjustment, and show that when the adjustment is acceptable, the predicted geometry is, in average, closer to the experimental one. An important consequence is that the terms of the intensity parameters related to dynamic coupling and electric dipole mechanisms will be unique. Hence, the important energy transfer rates will also be unique, leading to a single predicted intensity parameter for the 5D0→7F6 transition.

  5. Structural and spectroscopic analyses of europium doped yttrium oxyfluoride powders prepared by combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Rakov, Nikifor [PG-Ciência dos Materiais, Universidade Federal do Vale do São Francisco, 48902-300 Juazeiro, BA (Brazil); Guimarães, R. B.; Maciel, Glauco S. [Instituto de Física, Universidade Federal Fluminense, 24210-346 Niterói, RJ (Brazil); Lozano B, W. [Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil)

    2013-07-28

    A facile widely spread technique employed to produce low-cost high-yield oxide powders, combustion synthesis, was used to prepare yttrium oxyfluoride crystalline ceramic powders. The structure of the powders was analyzed by X-ray powder diffraction and Rietveld refinement. Samples heat treated at 700 °C had a predominance of vernier orthorhombic Y{sub 6}O{sub 5}F{sub 8} phase, while samples heat treated at 800 °C crystallized in stoichiometric rhombohedral YOF phase. The samples were doped with luminescent europium trivalent ions (Eu{sup 3+}) in different concentrations (1–15 wt.%) and Judd-Ofelt theory was used to probe the distortion from the inversion symmetry of the local crystal field and the degree of covalency between the rare-earth ion and the surrounding ligands. The luminescence lifetime was measured and the luminescence quantum efficiency (LQE) was estimated. We observed that Eu{sup 3+}:Y{sub 6}O{sub 5}F{sub 8} samples presented higher LQE in spite of the larger local crystal field anisotropy found for Eu{sup 3+}:YOF samples.

  6. Synthesis, photophysics, electrochemistry, thermal stability and electroluminescent performances of a new europium complex with bis(β-diketone) ligand containing carbazole group.

    Science.gov (United States)

    Liu, Jian; Liang, Quan-Bin; Wu, Hong-Bin

    2017-05-01

    We synthesized a new europium complex [Eu(ecbpd)3 (Phen)] with bis(β-diketone) ligand containing a carbazole group, in which ecbpd and Phen are dehydro-3,3'-(9-ethyl-9H-carbazole-3,6-diyl)bis(1-phenylpropane-1,3-dione) and 1,10-phenanthroline, respectively. Its UV/vis and photoluminescent spectra, quantum yield, luminescence lifetime, electrochemistry, thermal stability and electroluminescent performances were studied. This europium complex showed low efficiency luminescence, which is probably due to the mismatching energy levels of its ligand and Eu3+ , as well as the double Eu3+ core resonance. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Europium (III) PVC membrane sensor based on N-pyridine-2-carboxamido-8-aminoquinoline as a sensing material

    Energy Technology Data Exchange (ETDEWEB)

    Zamani, Hassan Ali, E-mail: haszamani@yahoo.com [Department of Applied Chemistry, Quchan branch, Islamic Azad University, Quchan (Iran, Islamic Republic of); Kamjoo, Rahman [Department of Applied Chemistry, Quchan branch, Islamic Azad University, Quchan (Iran, Islamic Republic of); Mohammadhosseini, Majid [Department of Chemistry, Faculty of Basic Sciences, Shahrood Branch, Islamic Azad University, Shahrood (Iran, Islamic Republic of); Zaferoni, Mojdeh; Rafati, Zynab [Department of Applied Chemistry, Quchan branch, Islamic Azad University, Quchan (Iran, Islamic Republic of); Ganjali, Mohammad Reza [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Faridbod, Farnoush [Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Meghdadi, Soraia [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2012-04-01

    Conductometric study in acetonitrile solution shows the selectivity of PCQ toward europium ion. Therefore, a new europium PVC membrane electrode was prepared based on N-pyridine-2-carboxamido-8-aminoquinoline (PCQ) as an ion carrier. The electrode has a wide concentration range from 1.0 Multiplication-Sign 10{sup -2} and 1.0 Multiplication-Sign 10{sup -6} mol L{sup -1}, Nernstian slope of 19.8 {+-} 0.3 mV per decade and a detection limit of 6.4 Multiplication-Sign 10{sup -7} mol L{sup -1}. The potentiometric response is pH independent in the range of 2.4-7.4. The proposed sensor has a relatively fast response time less than 10 s and it can be used for at least 2 months without any considerable divergence in its potentials. The proposed electrode revealed good selectivity toward europium ion in comparison with variety of other metal ions. The practical utility of the electrodes has been demonstrated by their use as indicator electrodes in the potentiometric titration of Eu{sup 3+} ions with EDTA and for determination of Eu{sup 3+} ion concentration in mixtures of two and three different ions. - Highlights: Black-Right-Pointing-Pointer A new ion carrier is introduced to preparation of a selective sensor for Eu{sup 3+} ions. Black-Right-Pointing-Pointer This technique is very simple and it's not necessary to use sophisticated equipment. Black-Right-Pointing-Pointer The novelty of this work is the high affinity of the ionophore toward the Eu{sup 3+} ions. Black-Right-Pointing-Pointer The sensor is superior to the formerly reported Eu{sup 3+} sensors in terms of selectivity.

  8. A novel tridentate bis(phosphinic acid)phosphine oxide based europium(III)-selective Nafion membrane luminescent sensor.

    Science.gov (United States)

    Sainz-Gonzalo, F J; Popovici, C; Casimiro, M; Raya-Barón, A; López-Ortiz, F; Fernández, I; Fernández-Sánchez, J F; Fernández-Gutiérrez, A

    2013-10-21

    A new europium(III) membrane luminescent sensor based on a new tridentate bis(phosphinic acid)phosphine oxide (3) system has been developed. The synthesis of this new ligand is described and its full characterization by NMR, IR and elemental analyses is provided. The luminescent complex formed between europium(III) chloride and ligand 3 was evaluated in solution, observing that its spectroscopic and chemical characteristics are excellent for measuring in polymer inclusion membranes. Included in a Nafion membrane, all the parameters (ligand and ionic additives) that can affect the sensitivity and selectivity of the sensing membrane as well as the instrumental conditions were carefully optimized. The best luminescence signal (λexc = 229.06 nm and λem = 616.02 nm) was exhibited by the sensing film having a Nafion : ligand composition of 262.3 : 0.6 mg mL(-1). The membrane sensor showed a short response time (t95 = 5.0 ± 0.2 min) and an optimum working pH of 5.0 (25 mM acetate buffer solution). The membrane sensor manifested a good selectivity toward europium(III) ions with respect to other trivalent metals (iron, chromium and aluminium) and lanthanide(III) ions (lanthanum, samarium, terbium and ytterbium), although a small positive interference of terbium(III) ions was observed. It provided a linear range from 1.9 × 10(-8) to 5.0 × 10(-6) M with a very low detection limit (5.8 × 10(-9) M) and sensitivity (8.57 × 10(-7) a.u. per M). The applicability of this sensing film has been demonstrated by analyzing different kinds of spiked water samples obtaining recovery percentages of 95-97%.

  9. A Responsive Europium(III) Chelate that Provides a Direct Readout of pH by MRI

    Science.gov (United States)

    Wu, Yunkou; Soesbe, Todd C.; Kiefer, Garry E.; Zhao, Piyu; Sherry, A. Dean

    2010-01-01

    A europium(III) DO3A-tris(amide) complex is reported for imaging pH by MRI using ratiometric CEST principles. Deprotonation of a single phenolic proton between pH 6 and 7.6 results in an ~5 ppm shift in the water exchange CEST peak that is easily detected by MRI. Collection of two CEST images at two slightly different activation frequencies provides a direct readout of solution pH without the need of a concentration marker. PMID:20853833

  10. Spectroscopic properties and luminescence behaviour of europium doped lithium borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Anjaiah, J., E-mail: anjaiah.juluru@gmail.com [Department of Physics, The University of Dodoma, Tanzania, East Africa (Tanzania, United Republic of); Department of Physics, Geethanjali College of Engineering and Technology, Keesara, RR Dist., Hyderabad 501 301 (India); Laxmikanth, C. [Department of Physics, The University of Dodoma, Tanzania, East Africa (Tanzania, United Republic of); Veeraiah, N. [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur 522 510, AP. (India)

    2014-12-01

    Li{sub 2}O–MO–B{sub 2}O{sub 3} (MO=ZnO, CaO and CdO) glasses doped with europium are prepared by using the melt quenching technique to study their absorption and luminescence properties to understand their lasing potentialities. The XRD pattern of the glasses confirmed the amorphous nature and the IR spectra reveal the presence of BO{sub 3} and BO{sub 4} units in the glass network. Judd–Ofelt intensity parameters Ω{sub λ} (λ=2, 4, 6) are evaluated from the intensities of various absorption bands of optical absorption spectra. The J–O parameters have been used to calculate transition probabilities (A), lifetime (τ{sub R}), branching ratios (β{sub R}) and stimulated emission cross-section (σ{sub P}) for the {sup 5}D{sub 0}→{sup 7}F{sub J} (J=1–4) transitions of the Eu{sup 3+} ions. The decay from the {sup 5}D{sub 0} level of Eu{sup 3+} ions in these glasses has been measured and analysed. Branching ratios and stimulated emission cross-sections measured for all these glasses show that the {sup 5}D{sub 0}→{sup 7}F{sub 1} transition under investigation has the potential for laser applications. The high stimulated emission cross-section and branching ratios from the present glasses suggests their potential for infra red lasers. The study of the thermoluminescence is also carried out and the data suggests that the CdBEu glass is suitable for thermoluminescence emission output among the three Eu{sup 3+} doped glasses.

  11. Size-dependent cytotoxicity of europium doped NaYF{sub 4} nanoparticles in endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shizhu; Zhang, Cuimiao; Jia, Guang; Duan, Jianlei; Wang, Shuxiang, E-mail: wsx@hbu.edu.cn; Zhang, Jinchao, E-mail: jczhang6970@163.com

    2014-10-01

    Lanthanide-doped sodium yttrium fluoride (NaYF{sub 4}) nanoparticles exhibit novel optical properties which make them be widely used in various fields. The extensive applications increase the chance of human exposure to these nanoparticles and thus raise deep concerns regarding their riskiness. In the present study, we have synthesized europium doped NaYF{sub 4} (NaYF{sub 4}:Eu{sup 3+}) nanoparticles with three diameters and used endothelial cells (ECs) as a cell model to explore the potential toxic effect. The cell viability, cytomembrane integrity, cellular uptake, intracellular localization, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP), apoptosis detection, caspase-3 activity and expression of inflammatory gene were studied. The results indicated that these nanoparticles could be uptaken into ECs and decrease the cell viability, induce the intracellular lactate dehydrogenase (LDH) release, increase the ROS level, and decrease the cell MMP in a size-dependent manner. Besides that, the cells were suffered to apoptosis with the caspase-3 activation, and the inflammation specific gene expressions (ICAM1 and VCAM1) were also increased. Our results suggest that the damage pathway may be related to the ROS generation and mitochondrial damage. The results provide novel evidence to elucidate their toxicity mechanisms and may be helpful for more rational applications of these compounds in the future. - Highlights: • NaYF{sub 4}:Eu{sup 3+} nanoparticles with three diameters have been synthesized. • NaYF{sub 4}:Eu{sup 3+} nanoparticles could be uptaken by endothelial cells (ECs). • NaYF{sub 4}:Eu{sup 3+} nanoparticles show a significant cytotoxicity on ECs. • The size of NaYF{sub 4}:Eu{sup 3+} nanoparticles may be important to their toxicology effect.

  12. Two-dimensional high spatial-resolution dosimeter using europium doped potassium chloride: a feasibility study

    Science.gov (United States)

    Li, H. Harold; Driewer, Joseph P.; Han, Zhaohui; Low, Daniel A.; Yang, Deshan; Xiao, Zhiyan

    2014-01-01

    Recent research has shown that KCl:Eu2+ has great potential for use in megavoltage radiation therapy dosimetry because this material exhibits excellent storage performance and is reusable due to strong radiation hardness. This work reports the authors’ attempts to fabricate 2D KCl:Eu2+ storage phosphor films (SPFs) using both a physical vapor deposition (PVD) method and a tape casting method. X ray diffraction analysis showed that a 10 µm thick PVD sample was composed of highly crystalline KCl. No additional phases were observed, suggesting that the europium activator had completed been incorporated into the KCl matrix. Photostimulated luminescence and photoluminescence spectra suggested that F (Cl-) centers were the electron storage centers post×ray irradiation and that Eu2+ cations acted as luminescence centers in the photostimulation process. The 150-µm thick casted KCl:Eu2+ SPF showed sub-millimeter spatial resolution. Monte Carlo simulations further demonstrated that the admixture of 20% KCl:Eu2+ and 80% low Z polymer binder exhibited almost no energy dependence in a 6 MV beam. KCl:Eu2+ pellet samples showed a large dynamic range from 0.01 cGy to 60 Gy dose-to-water, and saturated at approximately 500 Gy as a result of KCl’s intrinsic high radiation hardness. Taken together, this work provides strong evidence that KCl:Eu2+ based SPF with associated readout apparatus could result in a novel electronic film system that has all the desirable features associated with classic radiographic film and, importantly, water equivalence and the capability of permanent identification of each detector. PMID:24651448

  13. A Novel Europium Chelate Coated Nanosphere for Time-Resolved Fluorescence Immunoassay

    Science.gov (United States)

    Shen, Yifeng; Xu, Shaohan; He, Donghua

    2015-01-01

    A novel europium ligand 2, 2’, 2’’, 2’’’-(4, 7-diphenyl-1, 10-phenanthroline-2, 9-diyl) bis (methylene) bis (azanetriyl) tetra acetic acid (BC-EDTA) was synthesized and characterized. It shows an emission spectrum peak at 610 nm when it is excited at 360 nm, with a large Stock shift (250 nm). It is covalently coated on the surface of a bare silica nanosphere containi free amino groups, using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-Hydroxysuccinimide. We also observed an interesting phenomenon that when BC-EDTA is labeled with a silica nanosphere, the chelate shows different excitation spectrum peaks of about 295 nm. We speculate that the carboxyl has a significant influence on its excitation spectrum. The BC-EDTA/Eu3+coated nanosphere could be used as a fluorescent probe for time-resolved fluorescence immunoassay. We labeled the antibody with the fluorescent nanosphere to develop a nanosphere based hepatitis B surface antigen as a time-resolved fluorescence immunoassay reagent, which is very easy to operate and eliminates potential contamination of Eu3+ contained in the environment. The analytical and functional sensitivities are 0.0037 μg/L and 0.08 μg/L (S/N≥2.0) respectively. The detection range is 0.08-166.67 μg/L, which is much wider than that of ELISA (0.2-5μg/L). It is comparable to the commercial dissociation-enhanced lanthanide fluoro-immunoassay system (DELFIA) reagents (0.2-145μg/L). We propose that it can fulfill clinical applications. PMID:26056826

  14. A Novel Europium Chelate Coated Nanosphere for Time-Resolved Fluorescence Immunoassay.

    Directory of Open Access Journals (Sweden)

    Yifeng Shen

    Full Text Available A novel europium ligand 2,2',2'',2'''-(4,7-diphenyl-1,10-phenanthroline-2,9-diyl bis (methylene bis (azanetriyl tetra acetic acid (BC-EDTA was synthesized and characterized. It shows an emission spectrum peak at 610 nm when it is excited at 360 nm, with a large Stock shift (250 nm. It is covalently coated on the surface of a bare silica nanosphere containi free amino groups, using 1-ethyl-3-(3-dimethylaminopropyl carbodiimide hydrochloride and N-Hydroxysuccinimide. We also observed an interesting phenomenon that when BC-EDTA is labeled with a silica nanosphere, the chelate shows different excitation spectrum peaks of about 295 nm. We speculate that the carboxyl has a significant influence on its excitation spectrum. The BC-EDTA/Eu3+coated nanosphere could be used as a fluorescent probe for time-resolved fluorescence immunoassay. We labeled the antibody with the fluorescent nanosphere to develop a nanosphere based hepatitis B surface antigen as a time-resolved fluorescence immunoassay reagent, which is very easy to operate and eliminates potential contamination of Eu3+ contained in the environment. The analytical and functional sensitivities are 0.0037 μg/L and 0.08 μg/L (S/N≥2.0 respectively. The detection range is 0.08-166.67 μg/L, which is much wider than that of ELISA (0.2-5 μg/L. It is comparable to the commercial dissociation-enhanced lanthanide fluoro-immunoassay system (DELFIA reagents (0.2-145 μg/L. We propose that it can fulfill clinical applications.

  15. TOF SIMS analysis and generation of white photoluminescence from strontium silicate codoped with europium and terbium

    Energy Technology Data Exchange (ETDEWEB)

    Tshabalala, Modiehi A.; Swart, Hendrik C.; Ntwaeaborwa, Odireleng M., E-mail: ntwaeab@ufs.ac.za [Department of Physics, University of the Free State, P.O Box 339, Bloemfontein 9300 South Africa (South Africa)

    2014-03-15

    White light emitting terbium (Tb{sup 3+}) and europium (Eu{sup 3+}) codoped strontium silicate (Sr{sub 2}SiO{sub 4}) phosphors were prepared by a solid state reaction process. The structure, particle morphology, chemical composition, ion distribution, photoluminescence (PL), and decay characteristics of the phosphors were analyzed by x-ray diffraction (XRD), scanning electron microscopy (SEM), time-of-flight secondary ion mass spectrometry (TOF-SIMS), and PL spectroscopy, respectively. The XRD data showed that our Sr{sub 2}SiO{sub 4} composed of two phases, namely, β-Sr{sub 2}SiO{sub 4} and α′-Sr{sub 2}SiO{sub 4}, and the α′-Sr{sub 2}SiO{sub 4} phase was more prominent than the β-Sr{sub 2}SiO{sub 4} phase. The SEM micrographs showed that the particles were agglomerated together and they did not have definite shapes. All ions (i.e., negative and positive) present in our materials were identified by TOF-SIMS. In addition, the chemical imaging performed with the TOF-SIMS demonstrated how the individual ions including the dopants (Eu{sup 3+} and Tb{sup 3+}) were distributed in the host lattice. White photoluminescence was observed when the Sr{sub 2}SiO{sub 4}:Tb{sup 3+}, Eu{sup 3+} phosphor was excited at 239 nm using a monochromatized xenon lamp as the excitation source. The phosphor exhibited fast decay lifetimes implying that it is not a good candidate for long afterglow applications.

  16. Thermoluminescence of europium-doped zinc oxide exposed to beta particle irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Iriqui R, J. L.; Cruz V, C. [Universidad de Sonora, Departamento de Investigacion en Polimeros y Materiales, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Bernal, R. [Universidad de Sonora, Departamento de Investigacion en Fisica, Apdo. Postal 5-088, 83000 Hermosillo, Sonora (Mexico); Castano, V. M., E-mail: jorgeiriqui@gimmunison.com [UNAM, Instituto de Fisica, Centro de Fisica Aplicada y Tecnologia Avanzada, Apdo. Postal 1-1010, 76000 Queretaro, Qro. (Mexico)

    2015-10-15

    Full text: Zn O is a promising material for a range of optoelectronics applications, due to its direct wide band gap (E{sub g} ∼3.3 eV at 300 K) and large exciton binding energy (60 MeV). Its applications include UV light emitters, varistors, surface acoustic wave devices, piezoelectric transducers, and chemical and gas sensing. Rare-earth activation of phosphors has long been seen as an effective process since coupling energy into the rare-earth-ion site, either by ionization, charge exchange or a resonance energy process, results in light production. It is reported that Europium modifies the response thermoluminescence (Tl) for pure zinc oxide, when is irradiated with X-ray, created a peak at 365 degrees C. In this work, Zn O:Eu phosphors were synthesized by a chemical method. Some samples were exposed to beta particle irradiation for doses ranging from 1 up to 100 Gy. Tl response as a function of dose is linear throughout the studied dose range. The glow curve exhibits three maxima, centered at 176, 279 and 340 degrees C. The reusability studies obtained after ten repeated cycles of annealing irradiation readout for the Zn O:Eu shows that the variation in the Tl response is ten percent and tends to stabilization. The results indicate that these new Zn O:Eu phosphors are promising detectors and dosimeters for beta radiation. The structural and morphological characterization was carried out by X-ray diffraction and scanning electron microscopy, respectively. (Author)

  17. Synthesis and characterization of barium titanate, doped with europium and neodymium; Sintese e caracterizacao de titanato de bario, dopados com europio e neodimio

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Fernanda L.C.; Cabral, Alciney M.; Silva, Ademir O.; Oliveiro, Joao B.L., E-mail: nanda_louise@yahoo.com.br [Universidade Federal do Rio Grande do Norte (UFRN), Natal (Brazil). Instituto de Quimica

    2013-07-01

    This work aims at synthesize and characterize mixed oxides in Barium Titanium matrix in doping with Neodymium and Europium analyzing thermogravimetric curves, characteristic bands at infrared region of the polymer complex, which are intermediates to mixed oxides, and identify the formation thereof, and the crystallinity using XRD analysis.

  18. Stability constants of the Europium complexes with the chloride ions; Constantes de estabilidad de los complejos del europio con los iones cloruro

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez R, M.; Solache R, M.; Rojas H, A. [Instituto Nacional de Investigaciones Nucleares, Departamento de Quimica, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

    2000-07-01

    The stability constants of lanthanides complexes with chloride ions which were determined at the same ionic force but in different media, are significantly different. It does not exist a systematic study over these stability constants. The purpose of this work is to determine the stability constants of the europium complexes with chloride ions at 303 K, by the solvents extraction method. (Author)

  19. LA-ICP-MS Allows Quantitative Microscopy of Europium-Doped Iron Oxide Nanoparticles and is a Possible Alternative to Ambiguous Prussian Blue Iron Staining.

    Science.gov (United States)

    Scharlach, Constantin; Müller, Larissa; Wagner, Susanne; Kobayashi, Yuske; Kratz, Harald; Ebert, Monika; Jakubowski, Norbert; Schellenberger, Eyk

    2016-05-01

    The development of iron oxide nanoparticles for biomedical applications requires accurate histological evaluation. Prussian blue iron staining is widely used but may be unspecific when tissues contain substantial endogenous iron. Here we tested whether microscopy by laser ablation coupled to inductively coupled plasma mass spectrometry (LA-ICP-MS) is sensitive enough to analyze accumulation of very small iron oxide particles (VSOP) doped with europium in tissue sections. For synthesis of VSOP, a fraction of Fe3+ (5 wt%) was replaced by Eu3+, resulting in particles with 0.66 mol% europium relative to iron (Eu-VSOP) but with otherwise similar properties as VSOP. Eu-VSOP or VSOP was intravenously injected into ApoE-/- mice on Western cholesterol diet and accumulated in atherosclerotic plaques of these animals. Prussian blue staining was positive for ApoE-/- mice with particle injection but also for controls. LA-ICP-MS microscopy resulted in sensitive and specific detection of the europium of Eu-VSOP in liver and atherosclerotic plaques. Furthermore, calibration with Eu-VSOP allowed calculation of iron and particle concentrations in tissue sections. The combination of europium-doped iron oxide particles and LA-ICP-MS microscopy provides a new tool for specific and quantitative analysis of particle distribution at the tissue level and allows correlation with other elements such as endogenous iron.

  20. Novel Time-Resolved Fluorescence Europium Nanoparticle Immunoassay for Detection of Human Immunodeficiency Virus-1 Group O Viruses Using Microplate and Microchip Platforms.

    Science.gov (United States)

    Haleyur Giri Setty, Mohan Kumar; Liu, Jikun; Mahtani, Prerna; Zhang, Panhe; Du, Bingchen; Ragupathy, Viswanath; Devadas, Krishnakumar; Hewlett, Indira K

    2016-06-01

    Accurate detection and quantification of HIV-1 group O viruses have been challenging for currently available HIV assays. We have developed a novel time-resolved fluorescence (TRF) europium nanoparticle immunoassay for HIV-1 group O detection using a conventional microplate enzyme-linked immunosorbent assay (ELISA) and a microchip platform. We screened several antibodies for optimal reactivity with several HIV-1 group O strains and identified antibodies that can detect all the strains of HIV-1 group O that were available for testing. The antibodies were used to develop a conventional ELISA format assay and an in-house developed europium nanoparticle-based assay for sensitivity. The method was evaluated on both microwell plate and microchip platforms. We identified two specific and sensitive antibodies among the six we screened. The antibodies, C65691 and ANT-152, were able to quantify 15 and detect all 17 group O viruses, respectively, as they were broadly cross-reactive with all HIV-1 group O strains and yielded better signals compared with other antibodies. We have developed a sensitive assay that reflects the actual viral load in group O samples by using an appropriate combination of p24 antibodies that enhance group O detection and a highly sensitive TRF-based europium nanoparticle for detection. The combination of ANT-152 and C65690M in the ratio 3:1 was able to give significantly higher signals in our europium-based assay compared with using any single antibody.

  1. Lanthanide-to-lanthanide energy-transfer processes operating in discrete polynuclear complexes: can trivalent europium be used as a local structural probe?

    Science.gov (United States)

    Zaïm, Amir; Eliseeva, Svetlana V; Guénée, Laure; Nozary, Homayoun; Petoud, Stéphane; Piguet, Claude

    2014-09-15

    This work, based on the synthesis and analysis of chemical compounds, describes a kinetic approach for identifying intramolecular intermetallic energy-transfer processes operating in discrete polynuclear lanthanide complexes, with a special emphasis on europium-containing entities. When all coordination sites are identical in a (supra)molecular complex, only heterometallic communications are experimentally accessible and a Tb → Eu energy transfer could be evidenced in [TbEu(L5)(hfac)6] (hfac = hexafluoroacetylacetonate), in which the intermetallic separation amounts to 12.6 Å. In the presence of different coordination sites, as found in the trinuclear complex [Eu3(L2)(hfac)9], homometallic communication can be induced by selective laser excitation and monitored with the help of high-resolution emission spectroscopy. The narrow and non-degenerated character of the Eu((5)D0 ↔ (7)F0) transition excludes significant spectral overlap between donor and acceptor europium cations. Intramolecular energy-transfer processes in discrete polynuclear europium complexes are therefore limited to short distances, in agreement with the Fermi golden rule and with the kinetic data collected for [Eu3(L2)(hfac)9] in the solid state and in solution. Consequently, trivalent europium can be considered as a valuable local structural probe in discrete polynuclear complexes displaying intermetallic separation in the sub-nanometric domain, a useful property for probing lanthanido-polymers. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Optical isomers of N,N′-bis(1-phenylethyl)-2,6-pyridinedicarboxamide coordinated to europium(III) ions as reliable circularly polarized luminescence calibration standards†

    Science.gov (United States)

    Bonsall, Steven D.; Houcheime, Mona; Straus, Daniel A.; Muller, Gilles

    2009-01-01

    The synthesis of two optical isomers of N,N′-bis(1-phenylethyl)-2,6-pyridinedicarboxamide and the constant circularly polarized luminescence (CPL) activity of their acetonitrile trivalent europium complex solutions over a long period of time open new perspectives for performing accurate routine CPL calibration tests at low cost. PMID:17728891

  3. Photoluminescence behavior of europium (III) complexes containing 1-(4-tert-butylphenyl)-3-(2-naphthyl)-propane-1,3-dione ligand.

    Science.gov (United States)

    Wang, Dunjia; Zheng, Chunyang; Fan, Ling; Hu, Yanjun; Zheng, Jing

    2014-01-03

    Three novel europium complexes with 1-(4-tert-butylphenyl)-3-(2-naphthyl)-propane-1,3-dione (TNPD) and 2,2-dipyridine (Bipy) or 1,10-phenan-throline (Phen) were synthesized and confirmed by FT-IR, (1)H NMR, UV-vis absorption and elemental analysis. Photoluminescence behavior of complexes Eu(TNPD)3, Eu(TNPD)3·Bipy and Eu(TNPD)3·Phen were investigated in detail. Their emission spectra exhibited the characteristic emission bands that arise from the (5)D0→(7)FJ (J=0-4) transitions of the europium ion in solid state. Meanwhile, the results of their lifetime decay curves indicated that only one chemical environment existed around the europium ion. The intrinsic luminescence quantum efficiency (η) and the experimental intensity parameters (Ωt) of europium complexes were determined according to the emission spectra and luminescence decay curves in solid state. The complex Eu(TNPD)3·Phen showed much longer lifetime (τ) and higher luminescence quantum efficiency (η) than complexes Eu(TNPD)3 and Eu(TNPD)3·Bipy. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Synthesis, crystal structure and photophysical properties of europium(III) and terbium(III) complexes with pyridine-2,6-dicarboxamide

    NARCIS (Netherlands)

    Tanase, S.; Gallego, P.M.; Gelder, R. de; Fu, W.T.

    2007-01-01

    The reactions of pyridine-2,6-dicarboxamide with europium(III) and terbium(III) triflates led to the formation of mononuclear complexes of formula [Ln(pcam)(3)](CF3SO3)(3) (Ln = Eu 1, Tb 2; pcam stands for pyridine-2,6-dicarboxamide). From single-crystal X-ray diffraction analysis, the complexes

  5. Structural investigation and photoluminescent properties of gadolinium(III), europium(III) and terbium(III) 3-mercaptopropionate complexes.

    Science.gov (United States)

    Souza, E R; Mazali, I O; Sigoli, F A

    2014-01-01

    This work reports on the synthesis, crystallographic determination and spectroscopic characterization of gadolinium(III), terbium(III) and europium(III) 3-mercaptopropionate complexes, aqua-tris(3-mercaptopropionate)lanthanide(III)--[Ln(mpa)3(H2O)]. The Judd-Ofelt intensity parameters were experimentally determined from emission spectrum of the [Eu(mpa)3(H2O)]complex and they were also calculated from crystallographic data. The complexes are coordination polymers, where the units of each complex are linked together by carboxylate groups leading to an unidimensional and parallel chains that by chemical interactions form a tridimensional framework. The emission spectrum profile of the [Eu(mpa)3(H2O)] complex is discussed based on point symmetry of the europium(III) ion, that explains the bands splitting observed in its emission spectrum. Photoluminescent analysis of the [Gd(mpa)3(H2O)] complex show no efficient ligand excitation but an intense charge transfer band. The excitation spectra of the [Eu(mpa)3(H2O)] and [Tb(mpa)3(H2O)] complexes do not show evidence of energy transfer from the ligand to the excited levels of these trivalent ions. Therefore the emission bands are originated only by direct f-f intraconfigurational excitation of the lantanide(III) ions.

  6. Simple preparation of fluorescent composite films based on cerium and europium doped LaF3 nanoparticles

    Science.gov (United States)

    Secco, Henrique de L.; Ferreira, Fabio F.; Péres, Laura O.

    2018-03-01

    The combination of materials to form hybrids with unique properties, different from those of the isolated components, is a strategy used to prepare functional materials with improved properties aiming to allow their application in specific fields. The doping of lanthanum fluoride with other rare earth elements is used to obtain luminescent particles, which may be useful to the manufacturing of electronic devices' displays and biological markers, for instance. The application of the powder of nanoparticles has limitations in some fields; to overcome this, the powder may be incorporated in a suitable polymeric matrix. In this work, lanthanum fluoride nanoparticles, undoped and doped with cerium and europium, were synthesized through the co-precipitation method in aqueous solution. Aiming the formation of solid state films, composites of nanoparticles in an elastomeric matrix, the nitrile rubber (NBR), were prepared. The flexibility and the transparency of the matrix in the regions of interest are advantages for the application of the luminescent composites. The composites were applied as films using the casting and the spin coating techniques and luminescent materials were obtained in the samples doped with europium and cerium. Scanning electron microscopy images showed an adequate dispersion of the particles in the matrix in both film formation techniques. Aggregates of the particles were detected in the samples which may affect the uniformity of the emission of the composites.

  7. A microwave-assisted solution combustion synthesis to produce europium-doped calcium phosphate nanowhiskers for bioimaging applications.

    Science.gov (United States)

    Wagner, Darcy E; Eisenmann, Kathryn M; Nestor-Kalinoski, Andrea L; Bhaduri, Sarit B

    2013-09-01

    Biocompatible nanoparticles possessing fluorescent properties offer attractive possibilities for multifunctional bioimaging and/or drug and gene delivery applications. Many of the limitations with current imaging systems center on the properties of the optical probes in relation to equipment technical capabilities. Here we introduce a novel high aspect ratio and highly crystalline europium-doped calcium phosphate nanowhisker produced using a simple microwave-assisted solution combustion synthesis method for use as a multifunctional bioimaging probe. X-ray diffraction confirmed the material phase as europium-doped hydroxyapatite. Fluorescence emission and excitation spectra and their corresponding peaks were identified using spectrofluorimetry and validated with fluorescence, confocal and multiphoton microscopy. The nanowhiskers were found to exhibit red and far red wavelength fluorescence under ultraviolet excitation with an optimal peak emission of 696 nm achieved with a 350 nm excitation. Relatively narrow emission bands were observed, which may permit their use in multicolor imaging applications. Confocal and multiphoton microscopy confirmed that the nanoparticles provide sufficient intensity to be utilized in imaging applications. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  8. Europium nanoparticle-based simple to perform dry-reagent immunoassay for the detection of hepatitis B surface antigen.

    Science.gov (United States)

    Talha, Sheikh M; Salminen, Teppo; Juntunen, Etvi; Spangar, Anni; Gurramkonda, Chandrasekhar; Vuorinen, Tytti; Khanna, Navin; Pettersson, Kim

    2016-03-01

    Hepatitis B infection, caused by hepatitis B virus (HBV), presents a huge global health burden. Serological diagnosis of HBV mainly relies on the detection of hepatitis B surface antigen (HBsAg). Although there are high sensitivity commercial HBsAg enzyme immunoassays (EIAs) available, many low-resource laboratories lacking trained technicians continue to use rapid point-of-care assays with low sensitivities for HBsAg detection, due to their simplicity to operate. We developed a time-resolved fluorometric dry-reagent HBsAg immunoassay which meets the detection limit of high sensitivity EIAs but is simple to operate. To develop the assay, anti-HBsAg monoclonal antibody coated on europium nanoparticles was dried atop of biotinylated anti-HBsAg polyclonal antibody immobilized on streptavidin-coated microtiter wells. To test a sample in dry-reagent assay, serum sample and assay buffer were added to the wells, incubated, washed and europium signals were measured. The assay showed a detection limit of 0.25 ng/ml using HBsAg spiked in serum sample. When evaluated with 24 HBV positive and 37 negative serum samples, assay showed 100% sensitivity and specificity. Assay wells are stable for at least 26 weeks when stored at 4°C, and can tolerate elevated temperatures of up to 35°C for two weeks. The developed assay has high potential to be used in low-resource laboratories. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Bright mono-aqua europium complexes based on triazacyclononane that bind anions reversibly and permeate cells efficiently.

    Science.gov (United States)

    Butler, Stephen J; McMahon, Brian K; Pal, Robert; Parker, David; Walton, James W

    2013-07-15

    A series of five europium(III) complexes has been prepared from heptadentate N5O2 ligands that possess a brightness of more than 10 mM(-1) cm(-1) in water, following excitation over the range λ=330-355 nm. Binding of several oxy anions has been assessed by emission spectral titrimetric analysis, with the binding of simple carboxylates, lactate and citrate involving a common ligation mode following displacement of the coordinated water. Selectivity for bicarbonate allows the rapid determination of this anion in human serum, with K(d)=37 mM (295 K). The complexes are internalised quickly into mammalian cells and exhibit a mitochondrial localisation at early time points, migrating after a few hours to reveal a predominant lysosomal distribution. Herein, we report the synthesis and complexation behaviour of strongly emissive europium (III) complexes that bind oxy-anions in aqueous media with an affinity and selectivity profile that is distinctively different from previously studied systems. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Highly luminescent charge-neutral europium(iii) and terbium(iii) complexes with tridentate nitrogen ligands.

    Science.gov (United States)

    Senthil Kumar, Kuppusamy; Schäfer, Bernhard; Lebedkin, Sergei; Karmazin, Lydia; Kappes, Manfred M; Ruben, Mario

    2015-09-21

    We report on the synthesis of tridentate-nitrogen pyrazole-pyridine-tetrazole (L(1)H) and pyrazole-pyridine-triazole (L(2)H) ligands and their complexation with lanthanides (Ln = Gd(iii), Eu(iii) and Tb(iii)) resulting in stable, charge-neutral complexes Ln(L(1))3 and Ln(L(2))3, respectively. X-ray crystallographic analysis of the complexes with L(1) ligands revealed tricapped trigonal coordination geometry around the lanthanide ions. All complexes show bright photoluminescence (PL) in the solid state, indicating efficient sensitization of the lanthanide emission via the triplet states of the ligands. In particular, the terbium complexes show high PL quantum yields of 65 and 59% for L(1) and L(2), respectively. Lower PL efficiencies of the europium complexes (7.5 and 9%, respectively) are attributed to large energy gaps between the triplet states of the ligands and accepting levels of Eu(iii). The triplet state energy can be reduced by introducing an electron withdrawing (EW) group at the 4 position of the pyridine ring. Such substitution of L(1)H with a carboxylic ester (COOMe) EW group leads to a europium complex with increased PL quantum yield of 31%. A comparatively efficient PL of the complexes dissolved in ethanol indicates that the lanthanide ions are shielded against nonradiative deactivation via solvent molecules.

  11. Highly Sensitive Luminescence Assessment of Bile Acid Using a Balofloxacin-Europium(III) Probe in Micellar Medium

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Huan; Zhao, Fang; Si, Hailin; Zhang, Shuaishuai; Wang, Chunchun; Qi, Peirong [Shihezi Univ., Shihezi (China)

    2012-12-15

    A novel and simple method of luminescence enhancement effect for the determination of trace amounts of bile acid was proposed. The procedure was based on the luminescence intensity of the balofloxacin-europium(III) complex that could be strongly enhanced by bile acid in the presence of sodium dodecyl benzene sulfonate (SDBS). Under the optimum conditions, the enhanced luminescence intensity of the system exhibited a good linear relationship with the bile acid concentration in the range 5.0 Χ 10{sup -9} - 7.0 Χ 10{sup -7} mol L{sup -1} with a detection limit of 1.3 Χ 10{sup -9} mol L.1 (3σ). The relative standard deviation (RSD) was 1.7% (n = 11) for 5.0 Χ 10{sup -8} mol L{sup -1} bile acid. The applicability of the method to the determination of bile acid was demonstrated by investigating the effect of potential interferences and by analyzing human serum and urine samples. The possible enhancement mechanism of luminescence intensity in balofloxacin-europium(III)-bile acid-SDBS system was also discussed briefly.

  12. Investigation of the influence of silver and tin on the luminescence of trivalent europium ions in glass

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, J.A. [Department of Chemistry, University of Puerto Rico, Mayagueez, PR 00681 (United States); Lysenko, S. [Department of Physics, University of Puerto Rico, Mayagueez, PR 00681 (Puerto Rico); Liu, H., E-mail: hliu@uprm.ed [Department of Physics, University of Puerto Rico, Mayagueez, PR 00681 (Puerto Rico); Fachini, E.; Cabrera, C.R. [Center for Nanoscale Materials, University of Puerto Rico, Rio Piedras, PR 00931 (Puerto Rico)

    2010-01-15

    Europium-doped aluminophosphate glasses prepared by the melt-quenching technique have been studied by photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS). The effects of silver and tin doping, and of further thermal processing on Eu{sup 3+} ions luminescence have been assessed. For the glass system containing only europium, Eu{sup 3+} PL observed under UV excitation is suggested to occur through energy transfer from the excited glass host. After silver and tin doping, an enhanced UV excited Eu{sup 3+} PL has been indicated to occur essentially due to radiative energy transfer from isolated Ag{sup +} ions and/or two fold-coordinated Sn centers. Since thermal processing of the material leads to a quenching effect on Eu{sup 3+} PL and Ag nanoparticles (NPs) formation due to reduction of silver ions by tin, XPS was employed in order to investigate the possibility for Eu{sup 3+}->Eu{sup 2+} reduction during HT as a potential source of the PL decrease. The data points towards Ag NPs as main responsible for the observed weakening of Eu{sup 3+} PL.

  13. Alteration of osa-miR156e expression affects rice plant architecture and strigolactones (SLs) pathway.

    Science.gov (United States)

    Chen, Zhihui; Gao, Xinqiang; Zhang, Jian

    2015-05-01

    Overexpressing osa--miR156e in rice produced a bushy mutant and osa--miR156e regulation of tillering may do this through the strigolactones (SLs) pathway. Appropriate downregulation of osa--miR156 expression contributed to the improvement of plant architecture. Tillering is one of the main determinants for rice architecture and yield. In this study, a bushy mutant of rice was identified with increased tiller number, reduced plant height, prolonged heading date, low seed setting, and small panicle size due to a T-DNA insertion which essentially elevated the expression of osa-miR156e. Transgenic plants with constitutive expression of osa-miR156e also had the bushy phenotype, which showed osa-miR156 may control apical dominance and tiller outgrowth via regulating the strigolactones signaling pathway. Furthermore, the extent of impaired morphology was correlated with the expression level of osa-miR156e. In an attempt to genetically improve rice architecture, ectopic expression of osa-miR156e under the GAL4-UAS system or OsTB1 promoter was conducted. According to agronomic trait analysis, pTB1:osa-miR156e transgenic plants significantly improved the grain yield per plant compared to plants overexpressing osa-miR156e, even though the yield was still inferior to the wild type, making it a very interesting albeit negative result. Our results suggested that osa-miR156 could serve as a potential tool for modifying rice plant architecture through genetic manipulation of the osa-miR156 expression level.

  14. 25 CFR 15.6 - May my will be deemed revoked by operation of the law of any State?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false May my will be deemed revoked by operation of the law of any State? 15.6 Section 15.6 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR PROBATE PROBATE OF INDIAN ESTATES, EXCEPT FOR MEMBERS OF THE OSAGE NATION AND THE FIVE CIVILIZED TRIBES Introduction § 15.6 May my will be deemed revoked by...

  15. Convergent repression of miR156 by sugar and the CDK8 module of Arabidopsis Mediator.

    Science.gov (United States)

    Buendía-Monreal, Manuel; Gillmor, C Stewart

    2017-03-01

    In Arabidopsis, leaves produced during the juvenile vegetative phase are simple, while adult leaves are morphologically complex. The juvenile to adult transition is regulated by miR156, a microRNA that promotes juvenility by impeding the function of SPL transcription factors, which specify adult leaf traits. Both leaf derived sugars, as well as the Mediator Cyclin Dependent Kinase 8 (CDK8) module genes CENTER CITY (CCT)/MED12 and GRAND CENTRAL (GCT)/MED13, act upstream of miR156 to promote the juvenile to adult transition. However, it is not known whether sugar, CCT and GCT repress miR156 independently, as part of the same pathway, or in a cooperative manner. Here we show that sugar treatment can repress MIR156 expression in the absence of CCT or GCT. Both cct and the photosynthetic mutant chlorina1 (ch1) (which decreases sugar synthesis) exhibit extended juvenile development and increased MIR156A and MIR156C expression. Compared to ch1 and cct single mutants, the ch1 cct double mutant has a stronger effect on juvenile leaf traits, higher MIR156C levels, and a dramatic increase in MIR156A. Our results show that sugar and the CDK8 module are capable of regulating MIR156 independently, but suggest they normally act together in a synergistic manner. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Behaviour of europium (III) and its hydroxo and carbonate complexes in a solvent extraction system with HDBM in 2 M NaCl at 303 K

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez-Reyes, M. [Inst. Nacional de Investigaciones Nucleares, Dept. de Quimica, Mexico, D. F. (Mexico); Univ. Autonoma Metropolitana-Iztapalapa, Area de Electroquimica, Mexico, D. F. (Mexico); Solache-Rios, M. [Inst. Nacional de Investigaciones Nucleares, Dept. de Quimica, Mexico, D. F. (Mexico); Rojas-Hernandez, A. [Univ. Autonoma Metropolitana-Iztapalapa, Area de Electroquimica, Mexico, D. F. (Mexico)

    1999-07-01

    The behaviour of europium in the solvent extraction system Eu{sup 3+}-water-2 M NaCl-HDBM-benzene was studied, taking into account the pC{sub H} and the carbonate ion concentration in the solutions. The stability constants for the hydrolysis and carbonate complexes of europium were determined at 303 K in the same medium by pH titration followed by a computational refinement. The obtained data were: log {beta}{sub Eu,H} = -8.29 {+-} 0.02, log {beta}{sub Eu,2H} = -16.37 {+-} 0.02, log {beta}{sub Eu,3H} = -24.54 {+-} 0.11, log {beta}{sub Eu,4H} = -34.91 {+-} 0.26, log {beta}{sub CO{sub 2}{sup 2-},H} = 9.30 {+-} 0.05, log {beta}{sub Eu,CO{sub 3}{sup 2-}} = 5.96 {+-} 0.03, log {beta}{sub Eu,CO{sub 3}{sup 2-},H} = -1.24 {+-} 0.05 and log {beta}{sub Eu,CO{sub 3}{sup 2-},2H} = -11.39 {+-} 0.11. Log K{sub W} was -13.78 {+-} 0.06. The behaviour of europium in this solvent extraction system was simulated, taking into account the hydrolysis and carbonate complexes plus the formation of Eu(DBM){sub 3}(OH){sup 1-} and Eu(DBM){sub 3}(CO{sub 3}){sup 2-} in the aqueous phase. The only europium species considered in the organic phase was Eu(DBM){sub 3}. The first hydrolysis constant of europium was also determined by using this solvent extraction system under the same conditions. A good conformity was found with the results obtained by both techniques. (orig.)

  17. Bis(acridine-9-carboxylate)-nitro-europium(III) dihydrate complex a new apoptotic agent through Flk-1 down regulation, caspase-3 activation and oligonucleosomes DNA fragmentation.

    Science.gov (United States)

    Azab, Hassan A; Hussein, Belal H M; El-Azab, Mona F; Gomaa, Mohamed; El-Falouji, Abdullah I

    2013-01-01

    New bis(acridine-9-carboxylate)-nitro-europium(III) dihydrate complex was synthesized and characterized. In vivo anti-angiogenic activities of bis(acridine-9-carboxylate)-nitro-europium(III) dihydrate complex against Ehrlich ascites carcinoma (EAC) cells are described. The newly synthesized complex resulted in inhibition of proliferation of EAC cells and ascites formation. The anti-tumor effect was found to be through anti-angiogenic activity as evident by the reduction of microvessel density in EAC solid tumors. The anti-angiogenic effect is mediated through down-regulation of VEGF receptor type-2 (Flk-1). The complex was also found to significantly increase the level of caspase-3 in laboratory animals compared to the acridine ligand and to the control group. This was also consistent with the DNA fragmentation detected by capillary electrophoresis that proved the apoptotic effect of the new complex. Our complex exhibited anti-angiogenic and apoptotic activity in vivo, a thing that makes it a potential effective chemotherapeutic agent. The interaction of calf thymus DNA (ct-DNA) with bis(acridine-9-carboxylate)-nitro-europium(III) dihydrate complex has been investigated using fluorescence technique. A competitive experiment of the europium(III)-acridine complex with ethidium bromide (EB) to bind DNA revealed that interaction between the europium(III)-acridine and DNA was via intercalation. The interaction of the synthesized complex with tyrosine kinases was also studied using molecular docking simulation to further substantiate its mode of action. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. 18 CFR 156.3 - Applications; number of copies; general requirements.

    Science.gov (United States)

    2010-04-01

    ... ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER NATURAL GAS ACT APPLICATIONS FOR ORDERS UNDER SECTION 7(a) OF THE NATURAL GAS ACT § 156.3 Applications; number of copies; general... section 2 of the Natural Gas Act; State under the laws of which applicant is incorporated, organized or...

  19. Review and retrospective analysis of degenerative lumbosacral stenosis in 156 dogs treated by dorsal laminectomy.

    Science.gov (United States)

    Suwankong, N; Meij, B P; Voorhout, G; de Boer, A H; Hazewinkel, H A W

    2008-01-01

    The medical records of 156 dogs with degenerative lumbosacral stenosis (DLS) that underwent decompressive surgery were reviewed for signalment, history, clinical signs, imaging and surgical findings. The German Shepherd Dog (GSD) was most commonly affected (40/156, 25.6%). Pelvic limb lameness, caudal lumbar pain and pain evoked by lumbosacral pressure were the most frequent clinical findings. Radiography showed lumbosacral step formation in 78.8% (93/118) of the dogs which was associated with elongation of the sacral lamina in 18.6% (22/118). Compression of the cauda equina was diagnosed by imaging (epidurography, CT, or MRI) in 94.2% (147/156) of the dogs. Loss of the bright nucleus pulposus signal of the L7-S1 disc was found on T2-weighted MR images in 73.5% (25/34) of the dogs. The facet joint angle at L7-S1 was significantly smaller, and the tropism greater in GSD than in the other dog breeds. The smaller facet joint angle and higher incidence of tropism seen in the GSD may predispose this breed to DLS. Epidurography, CT, and MRI allow adequate visualization of cauda equina compression. During surgery, disc protrusion was found in 70.5% (110/156) of the dogs. Overall improvement after surgery was recorded in the medical records in 79.0% (83/105) of the dogs. Of the 38 owners that responded to questionnaires up to five years after surgery, 29 (76%) perceived an improvement.

  20. 21 CFR 133.156 - Low-moisture mozzarella and scamorza cheese.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Low-moisture mozzarella and scamorza cheese. 133... SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.156 Low-moisture mozzarella and scamorza cheese. (a...

  1. Yeast Interacting Proteins Database: YHR156C, YJR010W [Yeast Interacting Proteins Database

    Lifescience Database Archive (English)

    Full Text Available YHR156C LIN1 Non-essential component of U5 snRNP; nuclear protein; physically inter...6C Bait gene name LIN1 Bait description Non-essential component of U5 snRNP; nuclear protein; physically

  2. Europium(III) reduction and speciation within a Wells-Dawson heteropolytungstate.

    Science.gov (United States)

    Jing, Jing; Burton-Pye, Benjamin P; Francesconi, Lynn C; Antonio, Mark R

    2008-08-04

    The redox speciation of Eu(III) in the 1:1 stoichiometric complex with the alpha-1 isomer of the Wells-Dawson anion, [alpha-1-P 2W 17O 61] (10-), was studied by electrochemical techniques (cyclic voltammetry and bulk electrolysis), in situ XAFS (X-ray absorption fine structure) spectroelectrochemistry, NMR spectroscopy ( (31)P), and optical luminescence. Solutions of K 7[(H 2O) 4Eu(alpha-1-P 2W 17O 61)] in a 0.2 M Li 2SO 4 aqueous electrolyte (pH 3.0) show a pronounced concentration dependence to the voltammetric response. The fully oxidized anion and its reduced forms were probed by Eu L 3-edge XANES (X-ray absorption near edge structure) measurements in simultaneous combination with controlled potential electrolysis, demonstrating that Eu(III) in the original complex is reduced to Eu(II) in conjunction with the reduction of polyoxometalate (POM) ligand. After exhaustive reduction, the heteropoly blue species with Eu(II) is unstable with respect to cluster isomerization, fragmentation, and recombination to form three other Eu-POMs as well as the parent Wells-Dawson anion, alpha-[P 2W 18O 62] (6-). EXAFS data obtained for the reduced, metastable Eu(II)-POM before the onset of Eu(II) autoxidation provides an average Eu-O bond length of 2.55(4) A, which is 0.17 A longer than that for the oxidized anion, and consistent with the 0.184 A difference between the Eu(II) and Eu(III) ionic radii. The reduction of Eu(III) is unusual among POM complexes with Lindqvist and alpha-2 isomers of Wells-Dawson anions, that is, [Eu(W 5O 18) 2] (9-) and [Eu(alpha-2-As 2W 17O 61) 2] (17-), but not to the Preyssler complex anion, [EuP 5W 30O 110] (12-), and fundamental studies of materials based on coupling Eu and POM redox properties are still needed to address new avenues of research in europium hydrometallurgy, separations, and catalysis sciences.

  3. Structural, optical and electrical properties of europium picrate tetraethylene glycol complex as emissive material for OLED

    Energy Technology Data Exchange (ETDEWEB)

    Kusrini, Eny, E-mail: ekusrini@che.ui.ac.id [Department of Chemical Engineering, Faculty of Engineering, Universitas Indonesia, 16424 Depok (Indonesia); Saleh, Muhammad I.; Adnan, Rohana [School of Chemical Sciences, Universiti Sains Malaysia, 11800 Penang (Malaysia); Yulizar, Yoki [Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, 16424 Depok (Indonesia); Sha Shiong, Ng; Fun, H.K. [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Adhha Abdullah, M.A.; Mamat, Mazidah [Department of Chemical Sciences, Faculty of Science and Technology, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu Darul Iman (Malaysia); Za' aba, N.K.; Abd. Majid, W.H. [Solid State Research Laboratory, Department of Physics, Universiti Malaya, 50603 Kuala Lumpur (Malaysia)

    2012-01-15

    A new europium complex [Eu(Pic){sub 2}(H{sub 2}O)(EO4)](Pic).0.75H{sub 2}O was synthesized and used as the emission material for the single layer device structure of ITO/EO4-Eu-Pic/Al, using a spin-coating technique. Study on the optical properties of the [Eu(Pic){sub 2}(H{sub 2}O)(EO4)](Pic).0.75H{sub 2}O complex where EO4=tetraethylene glycol and Pic=picrate anion, had to be undertaken before being applicable to the study of an organic light emitting diode (OLED). The electrical property of an OLED using current-voltage (I-V) measurement was also studied. In complex, the Eu(III) ion was coordinated with the EO4 ligand as a pentadentate mode, one water molecule, and with two Pic anions as bidentate and monodentate modes, forming a nine-coordination number. The photoluminescence (PL) spectra of the crystalline complex in the solid state and its thin film showed a hypersensitive peak at 613.5-614.9 nm that assigned to the {sup 5}D{sub 0}{yields}{sup 7}F{sub 2} transition. A narrow band emission from the thin film EO4-Eu-Pic was obtained. The typical semiconductor I-V curve of device ITO/EO4-Eu-Pic/Al showed the threshold and turn on voltages at 1.08 and 4.6 V, respectively. The energy transfer process from the ligand to the Eu(III) ion was discussed by investigating the excitation and PL characteristics. Effect of the picrate anion on the device performance was also studied. - Highlights: > The [Eu(Pic){sub 2}(H{sub 2}O)(EO4)](Pic).0.75(H{sub 2}O) is crystallized in triclinic with space group P-1. > The complex is applied as a emissive center in single layer device structure of ITO/EO4-Eu-Pic/Al. > The complex displays a red luminescence in both the crystalline complex and its thin film state. > The low turn on voltage of the device (4.6 V), indicating that this material is suitable for OLED. > The roughness and morphology of the thin film affects luminance and electrical properties of OLED.

  4. Synthesis of Luminescent Ink from Europium-Doped Y2O3 Dispersed in Polyvinyl Alcohol Solution

    Directory of Open Access Journals (Sweden)

    Astuti

    2009-01-01

    Full Text Available Luminescent ink from europium-doped Y2O3 ( Y2O3:Eu has been synthesized by two steps method: first, synthesis of luminescent powder of Y2O3:Eu by simple heating of metallic nitrates in a polymer solution and second, dispersing the powder in a polyvinyl alcohol (PVA solution. The stability of the ink (luminescent colloid was strongly affected by mixing process of the powder and the solution. Mixing process must be performed for a long time (about 8 hours at above room temperature to product stable colloids. We observed that mixing at 30–40∘C resulted in a stable and highly dispersed colloid. The writing test was performed on a white paper to show the potential use of the colloid for making security codes.

  5. Induced europium CPL for the selective signalling of phosphorylated amino-acids and O-phosphorylated hexapeptides.

    Science.gov (United States)

    Neil, Emily R; Fox, Mark A; Pal, Robert; Parker, David

    2016-05-17

    Two bright, europium(iii) complexes based on an achiral heptadentate triazacyclononane ligand bearing two strongly absorbing chromophores have been evaluated for the selective emission and CPL signalling of various chiral O-phosphono-anions. Binding of O-phosphono-Ser and Thr gives rise to a strong induced CPL signature and a favoured Δ complex configuration is adopted. A similarly large induced CPL signal arises when [Eu·](2+) binds to lysophosphatidic acid (LPA), where the strong binding (log K 5.25 (295 K)) in methanol allowed its detection over the range 5 to 40 μM. Strong and chemoselective binding to the phosphorylated amino-acid residues was also observed with a set of four structurally related hexapeptides: in one case, the sign of the gem value in the ΔJ = 1 transition allowed differentiation between the binding to O-P-Ser and O-P-Tyr residues.

  6. A new europium(III)-β-diketonate complex based on diphenylethyne as red phosphors applied in LED

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Guang, E-mail: shaog@mail.sysu.edu.cn [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Zhang, Na; Lin, Duan [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Feng, Kenjun [Department of Chemical Engineering, Hui-Zhou University, Huizhou 516007 (China); Cao, Rihui, E-mail: caorihui@mail.sysu.edu.cn [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Gong, Menglian [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China)

    2013-06-15

    A new europium(III) ternary complex based on a fluorinated β-diketonate ligand and 1,10-phenanthroline as an ancillary ligand has been prepared and evaluated as a candidate for light-emitting diode (LED). The complex exhibits a high decomposition temperature (316 °C). Photophysical properties such as FT-IR spectra, UV–vis absorption spectra, excitation and emission spectra, luminescence decay curve and quantum yield were investigated. The excitation band is well matched with the characteristic emission of 395 nm-emitting InGaN chips. The complex exhibits an efficient energy transfer pathway from the ligands to the central Eu{sup 3+} ion via a ligand-sensitized luminescence process. An intense red-emitting LED was fabricated by coating the complex onto a 395 nm-emitting InGaN chip, and its Commission International de I'Eclairage (CIE) chromaticity coordinate (x=0.6389, y=0.3255) is close to the National Television Standard Committee (NTSC) standard value for red color. Meanwhile, the energy transfer from the InGaN chip to the complex is very efficient. All the findings demonstrate the potential application of the Eu(III) complex as red-emitting phosphors for UV-based white LEDs. -- Highlights: ► A new europium(III)-β-diketonate complex was synthesized and characterized. ► Thermal stability and photophysical properties were investigated in detail. ► PL mechanism was proposed to involve a ligand-sensitized luminescence process. ► An intense red-emitting LED was fabricated by using the complex. ► CIE chromaticity coordinate is close to NTSC standard value for red color.

  7. Mitochondria Targetable Time-Gated Luminescence Probe for Singlet Oxygen Based on a β-Diketonate-Europium Complex.

    Science.gov (United States)

    Sun, Jingyan; Song, Bo; Ye, Zhiqiang; Yuan, Jingli

    2015-12-21

    Singlet oxygen ((1)O2) plays a key role in the photodynamic therapy (PDT) technique of neoplastic diseases. In this work, by using a 9,10-dimethyl-2-anthryl-containing β-diketone, 1,1,1,2,2-pentafluoro-5-(9',10'-dimethyl-2'-anthryl)-3,5-pentanedione (Hpfdap), as a (1)O2-recognition ligand, a novel β-diketonate-europium(III) complex that can act as a luminescence probe for (1)O2, [Eu(pfdap)3(tpy)] (tpy = 2,2',2″-terpyridine), has been designed and synthesized for the time-gated luminescence detection of (1)O2 in living cells. The complex is weakly luminescent due to the quenching effect of 9,10-dimethyl-2-anthryl groups. After reaction with (1)O2, accompanied by the formation of endoperoxides of 9,10-dimethyl-2-anthryl groups, the luminescence quenching disappears, so that the long-lived luminescence of the europium(III) complex is switched on. The complex showed highly selective luminescence response to (1)O2 with a remarkable luminescence enhancement. Combined with the time-gated luminescence imaging technique, the complex was successfully used as a luminescent probe for the monitoring of the time-dependent generation of (1)O2 in 5-aminolevulinic acid (a PDT drug) loaded HepG2 cells during the photodynamic process. In addition, by coloading the complex and a mitochondrial indicator, Mito-Tracker Green, into HepG2 cells, the specific localization of [Eu(pfdap)3(tpy)] molecules in mitochondria of HepG2 cells was demonstrated by confocal fluorescence imaging measurements.

  8. Lightcurve Analysis of NEA (190166) 2005 UP156: A New Fully-Synchronous Binary

    Science.gov (United States)

    Warner, Brian D.; Harris, Alan W.; Aznar Macias, Amadeo; Oey, Julian

    2017-10-01

    CCD photometric observations of the near-Earth asteroid (190166) 2005 UP156 in 2017 May show it to be a fully-synchronous binary with rotation and orbital period P = 40.542 ± 0.008 h. The estimated effective diameter ratio of the two bodies is 0.8 ± 0.1. However, the 0.5 mag out-of-eclipse lightcurve indicates quite elongated shapes and so the size ratio should be viewed with caution.

  9. Application of NCRP 156 Wound Models for the Analysis of Bioassay Data from Plutonium Wound Cases.

    Science.gov (United States)

    Poudel, Deepesh; Guilmette, Raymond A; Klumpp, John A; Bertelli, Luiz; Waters, Tom L

    2017-09-01

    The NCRP 156 wound model was heavily based on data from animal experiments. The authors of the report acknowledged this limitation and encouraged validation of the models using data from human wound exposures. The objective of this paper was to apply the NCRP 156 wound models to the bioassay data from four plutonium-contaminated wound cases reported in the literature. Because a wide variety of forms of plutonium can be expected at a nuclear facility, a combination of the wound models-rather than a single model-was used to successfully explain both the urinary excretion data and wound retention data in three cases. The data for the fourth case could not be explained by any combination of the default wound models. While this may possibly be attributed to the existence of a category of plutonium whose solubility and chemistry are different than those described by the NCRP 156 default categories, the differences may also be the result of differences in systemic biokinetics. The concept of using a combination of biokinetic models may be extended to inhalation exposures as well, where more than one form of radionuclide-particles of different solubility or different sizes-may exist in a workplace.

  10. Comparative transcriptome investigation of global gene expression changes caused by miR156 overexpression in Medicago sativa.

    Science.gov (United States)

    Gao, Ruimin; Austin, Ryan S; Amyot, Lisa; Hannoufa, Abdelali

    2016-08-19

    Medicago sativa (alfalfa) is a low-input forage and potential bioenergy crop, and improving its yield and quality has always been a focus of the alfalfa breeding industry. Transgenic alfalfa plants overexpressing a precursor of alfalfa microRNA156 (MsmiR156) were recently generated by our group. These plants (miR156OE) showed enhanced biomass yield, reduced internodal length, increased shoot branching and trichome density, and a delay in flowering time. Transcripts of three SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL) genes (MsSPL6, MsSPL12, and MsSPL13) were found to be targeted for cleavage by MsmiR156 in alfalfa. To further illustrate the molecular mechanisms underlying the effects of miR156 in alfalfa, two miR156OE genotypes (A11a and A17) were subjected to Next Generation RNA Sequencing with Illumina HiSeq. More than 1.11 billion clean reads were obtained from our available sequenced samples. A total of 160,472 transcripts were generated using Trinity de novo assembly and 4,985 significantly differentially expressed genes were detected in miR156OE plants A11a and A17 using the Medicago truncatula genome as reference. A total of 17 genes (including upregulated, downregulated, and unchanged) were selected for quantitative real-time PCR (qRT-PCR) validation, which showed that gene expression levels were largely consistent between qRT-PCR and RNA-Seq data. In addition to the established SPL genes MsSPL6, MsSPL12 and MsSPL13, four new SPLs; MsSPL2, MsSPL3, MsSPL4 and MsSPL9 were also down-regulated significantly in both miR156OE plants. These seven SPL genes belong to genes phylogeny clades VI, IV, VIII, V and VII, which have been reported to be targeted by miR156 in Arabidopsis thaliana. The gene ontology terms characterized electron transporter, starch synthase activity, sucrose transport, sucrose-phosphate synthase activity, chitin binding, sexual reproduction, flavonoid biosynthesis and lignin catabolism correlate well to the phenotypes of miR156OE alfalfa

  11. Excitation energy transfer in europium chelate with doxycycline in the presence of a second ligand in micellar solutions of nonionic surfactants

    Science.gov (United States)

    Smirnova, T. D.; Shtykov, S. N.; Kochubei, V. I.; Khryachkova, E. S.

    2011-01-01

    The complexation of Eu3+ with doxycycline (DC) antibiotic in the presence of several second ligands and surfactant micelles of different types is studied by the spectrophotometric and luminescence methods. It is found that the efficiency of excitation energy transfer in Eu3+-DC chelate depends on the nature of the second ligand and surfactant micelles. Using thenoyltrifluoroacetone (TTA) as an example, it is shown that the second ligand additionally sensitizes the europium fluorescence, and the possibility of intermediate sensitization of DC and then of europium is shown by the example of 1,10-phenanthroline. In all cases, the excitation energy transfer efficiency was increased due to the so-called antenna effect. The decay kinetics of the sensitized fluorescence of the binary and mixed-ligand chelates in aqueous and micellar solutions of nonionic surfactants is studied and the relative quantum yields and lifetimes of fluorescence are determined.

  12. A Smart Europium-Ruthenium Complex as Anticancer Prodrug: Controllable Drug Release and Real-Time Monitoring under Different Light Excitations.

    Science.gov (United States)

    Li, Hongguang; Xie, Chen; Lan, Rongfeng; Zha, Shuai; Chan, Chi-Fai; Wong, Wing-Yan; Ho, Ka-Lok; Chan, Brandon Dow; Luo, Yuxia; Zhang, Jing-Xiang; Law, Ga-Lai; Tai, William C S; Bünzli, Jean-Claude G; Wong, Ka-Leung

    2017-11-09

    A unique, dual-function, photoactivatable anticancer prodrug, RuEuL, has been tailored that features a ruthenium(II) complex linked to a cyclen-europium chelate via a π-conjugated bridge. Under irradiation at 488 nm, the dark-inactive prodrug undergoes photodissociation, releasing the DNA-damaging ruthenium species. Under evaluation-window irradiation (λirr = one-photon 350 nm or two-photon 700 nm), the drug delivery process can be quantitatively monitored in real-time because of the long-lived red europium emission. Linear relationships between released drug concentration and ESI-MS or luminescence responses are established. Finally, the efficiency of the new prodrug is demonstrated both in vitro RuEuL anticancer prodrug over some existing ones and open the way for decisive improvements in multipurpose prodrugs.

  13. Structural and optical analysis on europium doped AZrO{sub 3} (A=Ba, Ca, Sr) phosphor for display devices application

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, Vikas, E-mail: jsvikasdubey@gmail.com [Department of Physics, Bhilai Institute of Technology Raipur, 493661 (India); Tiwari, Neha [Department of Physics, Govt. Model Science College, Jabalpur (India)

    2016-05-06

    Behavior displayed by europium doped AZrO{sub 3} phosphor which was synthesized by solid state reaction method. For synthesis of BaZrO{sub 3}, SrZrO{sub 3} and CaZrO{sub 3} phosphor with fixed concentration of europium ion was calcination at 1000°C and sintered at 1300°C following intermediate grinding. Synthesized sample was characterized by X-ray diffraction analysis and crystallite sized was calculated by Scherer’s formula. From PL spectra of prepared phosphors shows intense emission centred at 612nm (red emission) with high intensity for SrZrO{sub 3}:Eu{sup 3+}. For europium doped BaZrO{sub 3} and CaZrO{sub 3} (613nm) phosphor shows less intense PL spectra as compared to SrZrO{sub 3}:Eu{sup 3+}. The strong emission peak of AZrO{sub 3}:Eu{sup 3+} phosphor is due to forced electric dipole transition of {sup 5}D{sub 0} to {sup 7}F{sub 2} centered at 612 and 613nm. It is characteristic red emission for europium ion. The excitation spectra of AZrO{sub 3}:Eu{sup 3+} phosphor mainly consists of the charge transfer and (CTB) of Eu{sup 3+} located in 200–350 nm centred at 254nm. The present phosphors can act as single host for red light emission in display devices. The CIE coordinates were calculated by Spectrophotometric method using the spectral energy distribution of the AZrO{sub 3}:Eu{sup 3+} sample.

  14. Metal-organic framework luminescence in the yellow gap by codoping of the homoleptic imidazolate ∞(3)[Ba(Im)2] with divalent europium.

    Science.gov (United States)

    Rybak, Jens-Christoph; Hailmann, Michael; Matthes, Philipp R; Zurawski, Alexander; Nitsch, Jörn; Steffen, Andreas; Heck, Joachim G; Feldmann, Claus; Götzendörfer, Stefan; Meinhardt, Jürgen; Sextl, Gerhard; Kohlmann, Holger; Sedlmaier, Stefan J; Schnick, Wolfgang; Müller-Buschbaum, Klaus

    2013-05-08

    The rare case of a metal-triggered broad-band yellow emitter among inorganic-organic hybrid materials was achieved by in situ codoping of the novel imidazolate metal-organic framework ∞(3)[Ba(Im)2] with divalent europium. The emission maximum of this dense framework is in the center of the yellow gap of primary light-emitting diode phosphors. Up to 20% Eu2+ can be added to replace Ba2+ as connectivity centers without causing observable phase segregation. High-resolution energy-dispersive X-ray spectroscopy showed that incorporation of even 30% Eu2+ is possible on an atomic level, with 2-10% Eu2+ giving the peak quantum efficiency (QE = 0.32). The yellow emission can be triggered by two processes: direct excitation of Eu2+ and an antenna effect of the imidazolate linkers. The emission is fully europium-centered, involving 5d → 4f transitions, and depends on the imidazolate surroundings of the metal ions. The framework can be obtained by a solvent-free in situ approach starting from barium metal, europium metal, and a melt of imidazole in a redox reaction. Better homogeneity for the distribution of the luminescence centers was achieved by utilizing the hydrides BaH2 and EuH2 instead of the metals.

  15. α-Titanium phosphate intercalated with propylamine: An alternative pathway for efficient europium(III uptake into layered tetravalent metal phosphates

    Directory of Open Access Journals (Sweden)

    Jorge García-Glez

    2017-09-01

    Full Text Available α-Ti(HPO42·H2O (α-TiP and its propylamine intercalation product, Ti(HPO42·2C3H7NH2·H2O (α-TiPPr, have been synthesized and characterized. Later, their sorption capacity for europium(III was investigated, and this purpose was accomplished by treating α-TiP and α-TiPPr with europium(III nitrate solutions at different concentrations until the equilibrium is reached. All samples were characterized, among others, by powder X-ray diffraction (PXRD, scanning and transmission electron microscopies (SEM, TEM, STEM-EDX, SAED, thermogravimetric analysis (TGA, and photoluminescence (PL measurements. The results show that the Eu3+ uptake is limited to surface when α-TiP is used as sorbent. Nevertheless, the Eu-retention is considerably enhanced with α-TiPPr as a consequence of an ion-exchange process into the interlayer space of the layered titanium phosphate (involving propylammonium cations, C3H7NH3+, and hexahydrate europium(III species, [Eu(H2O6]3+, and the crystal structure of a hypothetical final product, α-[Eu(H2O6]2/3Ti(PO42·[(H2O6]1/3, has been proposed by using DFT calculations.

  16. Lithium ionophore VIII as an extraordinarily strong receptor for the trivalent europium cation

    Science.gov (United States)

    Makrlík, Emanuel; Novák, Vít; Vaňura, Petr

    2015-01-01

    On the basis of extraction experiments and γ-activity measurements, the extraction constant corresponding to the equilibrium Eu3+(aq) + 3A-(aq) + 1(nb) ⇆ 1.Eu3+(nb) + 3A-(nb) occurring in the two-phase water-nitrobenzene system (A- = CF3SO-3; 1 = lithium ionophore VIII; aq = aqueous phase, nb = nitrobenzene phase) was determined as log Kex (1.Eu3+, 3A-) = 2.5 ± 0.1. Furthermore, the extremely high stability constant of the 1.Eu3+ complex in nitrobenzene saturated with water was calculated: log βnb (1.Eu3+) = 15.6 ± 0.1. Finally, by using DFT calculations, the most probable structure of the cationic complex species 1.Eu3+ was derived. In the resulting complex, the 'central' cation Eu3+ is bound by six very strong bond interactions to the corresponding six oxygen atoms of the parent ligand 1. It is evident that this exceptionally effective receptor 1 for the Eu3+ cation could be considered as a potential extraction agent for nuclear waste treatment.

  17. Electron tunneling transport across heterojunctions between europium sulfide and indium arsenide

    Science.gov (United States)

    Kallaher, Raymond L.

    This dissertation presents research done on utilizing the ferromagnetic semiconductor europium sulfide (EuS) to inject spin polarized electrons into the non-magnetic semiconductor indium arsenide (InAs). There is great interest in expanding the functionality of modern day electronic circuits by creating devices that depend not only on the flow of charge in the device, but also on the transport of spin through the device. Within this mindset, there is a concerted effort to establish an efficient means of injecting and detecting spin polarized electrons in a two dimensional electron system (2DES) as the first step in developing a spin based field effect transistor. Thus, the research presented in this thesis has focused on the feasibility of using EuS, in direct electrical contact with InAs, as a spin injecting electrode into an InAs 2DES. Doped EuS is a concentrated ferromagnetic semiconductor, whose conduction band undergoes a giant Zeeman splitting when the material becomes ferromagnetic. The concomitant difference in energy between the spin-up and spin-down energy bands makes the itinerant electrons in EuS highly spin polarized. Thus, in principle, EuS is a good candidate to be used as an injector of spin polarized electrons into non-magnetic materials. In addition, the ability to adjust the conductivity of EuS by varying the doping level in the material makes EuS particularly suited for injecting spins into non-magnetic semiconductors and 2DES. For this research, thin films of EuS have been grown via e-beam evaporation of EuS powder. This growth technique produces EuS films that are sulfur deficient; these sulfur vacancies act as intrinsic electron donors and the resulting EuS films behave like heavily doped ferromagnetic semiconductors. The growth parameters and deposition procedures were varied and optimized in order to fabricate films that have minimal crystalline defects. Various properties and characteristics of these EuS films were measured and compared to

  18. Bacillus cereus AR156 induces resistance against Rhizopus rot through priming of defense responses in peach fruit.

    Science.gov (United States)

    Wang, Xiaoli; Xu, Feng; Wang, Jing; Jin, Peng; Zheng, Yonghua

    2013-01-15

    The biocontrol effects of Bacillus cereus AR156 on Rhizopus rot caused by Rhizopus stolonifer in postharvest peach fruit and the possible mechanisms were investigated. The results showed that fruit treated with B. cereus AR156 had significantly lower disease incidence and smaller lesion diameter than the control fruit did. B. cereus AR156 treatment remarkably enhanced activities of chitinase and β-1,3-glucanase, promoted accumulation of H(2)O(2), and improved total phenolic content and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity. Transcripts of four defense related genes were only significantly enhanced in fruit both treated with B. cereus AR156 and inoculated with R. stolonifer compared with those that were only treated with B. cereus AR156 or inoculated with R. stolonifer. These results suggest that B. cereus AR156 can effectively inhibit Rhizopus rot caused by R. stolonifer and enhance antioxidant activity in peach fruit through the priming of defense responses. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Synthesis, Optical Investigation and Biological Properties of Europium(III) Complexes with 2-(4-Chlorophenyl)-1-(2-Hydroxy-4-Methoxyphenyl)Ethan-1-one and Ancillary Ligands.

    Science.gov (United States)

    Nandal, Poonam; Khatkar, S P; Kumar, Rajesh; Khatkar, Avni; Taxak, V B

    2017-01-01

    Synthesis and photoluminescence behaviour of six novel europium complexes with novel β-hydroxyketone ligand, 2-(4-chlorophenyl)-1-(2-hydroxy-4-methoxyphenyl)ethan-1-one (CHME) and 2,2'-bipyridine (bipy) or neocuproine (neo) or 1,10-phenanthroline (phen) or 5,6-dimethyl-1,10-phenanthroline (dmphen) or bathophenanthroline (bathophen) were reported in solid state. The free ligand CHME and europium complexes, Eu(CHME)3.2H2O [1] Eu(CHME)3.bipy [2], Eu(CHME)3.neo [3], Eu(CHME)3.phen [4], Eu(CHME)3.dmphen [5] and Eu(CHME)3.bathophen [6]were characterized by elemental analysis, FT-IR and 1H-NMR. The photoluminescence emission spectra exhibited four characteristic peaks arising from the 5D0 → 7FJ (J = 1-4) transitions of the europium ion in the solid state on monitoring excitation at λex = 395 nm. The luminescence decay curves of these europium complexes possess single exponential behaviour indicating the presence of a single luminescent species and having only one site symmetry in the complexes. The luminescence quantum efficiency (η) and the experimental intensity parameters, Ω 2 and Ω 4 of europium complexes have also been calculated on the basis of emission spectra and luminescence decay curves. In addition, the antimicrobial and antioxidant activities were also studied of the investigated complexes.

  20. Highly luminescent pure-red-emitting fluorinated β-diketonate europium(III) complex for full solution-processed OLEDs

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Joao P. [CEMDRX, Physics Department, Universidade de Coimbra, Rua Larga, Coimbra P-3004-516 (Portugal); Serviço de Medicina Nuclear, SESARAM E.P.E., Avenida Luís de Camões 57, Funchal 9004-514, Madeira (Portugal); Martín-Ramos, Pablo [CEMDRX, Physics Department, Universidade de Coimbra, Rua Larga, Coimbra P-3004-516 (Portugal); Higher Technical School of Telecommunications Engineering, Universidad de Valladolid, Campus Miguel Delibes, Paseo Belén 15, Valladolid 47011 (Spain); Coya, Carmen, E-mail: carmen.coya@urjc.es [Escuela Superior de Ciencias Experimentales y Tecnología (ESCET), Universidad Rey Juan Carlos, Madrid 28933 (Spain); Silva, Manuela Ramos [CEMDRX, Physics Department, Universidade de Coimbra, Rua Larga, Coimbra P-3004-516 (Portugal); Eusebio, M. Ermelinda S. [Chemistry Department, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, Coimbra P-3004-535 (Portugal); Andrés, Alicia de [Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas (CSIC), Cantoblanco, Madrid 28049 (Spain); Álvarez, Ángel L. [Escuela Superior de Ciencias Experimentales y Tecnología (ESCET), Universidad Rey Juan Carlos, Madrid 28933 (Spain); Martín-Gil, Jesús [Advanced Materials Laboratory, ETSIIAA, Universidad de Valladolid, Avenida de Madrid 44, Palencia 34004 (Spain)

    2015-03-15

    Current manufacturing technologies for OLEDs involve the use of expensive high vacuum techniques and call for thermal stability requirements which are not fulfilled by many materials. These problems disappear when the OLED films are deposited directly from solution. In this study, we have designed, synthesized and characterized a novel octacoordinated complex, Tris(1-(4-chlorophenyl)-4,4,4-trifluoro-1, 3-butanedionate)mono(bathophenanthroline) europium(III), to be used as a “complex-only” emissive layer in wet-processed OLEDs. Upon excitation in the UV region, very efficient energy transfer from the ligands to Eu{sup 3+} takes place, giving rise to intense red emission with very high monochromaticity (R=19), both in powder and as a thin film. The decay times of 754 µs (powder) and 620 µs (thin film) are comparable to those of the most efficient Eu{sup 3+} β-diketonate complexes reported to date. The same energy transfer leading to saturated red and narrow emission is also observed in the OLED device (glass/ITO/PEDOT:PSS/[Eu(cbtfa){sub 3}(bath)]/Ca/Al) when biased at >5.2 V. Its high quantum efficiency (∼60%), good thermal stability up to 200 °C and adequate thin film forming properties make this material a promising chromophore for cost-effective OLEDs. - Highlights: • A highly fluorinated europium(III) octacoordinated complex, [Eu(cbtfa)3(bath)], has been synthesized and its structure elucidated by single crystal X-ray diffraction. • The chosen coordination environment is well-suited for sensitizing the luminescence of the Eu{sup 3+} ion, achieving very efficient energy transfer from the organic ligands (excited in the UV region) to the rare earth ion, leading to highly efficient (Q∼60% in crystalline powder and Q∼50% in thin film) and saturated red photoluminescence. • The material has also been integrated into a single active layer, full solution-processed OLED, with ITO/PEDOT:PSS/[Eu(cbtfa)3(bath)]/ Ca/Al structure.

  1. Simultaneous analysis of free and humic acid complexed europium and gadolinium species by CE-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Kautenburger, R.; Nowotka, K.; Beck, H.P. [Institut fuer Anorganische und Analytische Chemie und Radiochemie, Universitaet des Saarlandes, P.O. Box 151150, 66041 Saarbruecken (Germany)

    2005-07-01

    Full text of publication follows: For the long-term safety assessment of waste repositories, detailed information about geo-chemical behaviour of radioactive and toxic metal ions under environmental conditions (geological matrix and aquifer systems) is necessary. It includes knowledge about the mechanism of relevant geochemical reactions, as well as thermodynamic and kinetic data. Several previous studies have shown that humic acid can play an important role in the immobilisation or mobilization of metal ions due to complexation and colloid formation. In this project we investigate the complexation behaviour of humic acid (purified Aldrich humic acid) and its influence on the migration of the lanthanides europium and gadolinium (homologues of the actinides americium and curium) in the the ternary system consisting of these heavy metals, humic acid and kaolinite (KGa-1b) as geological model system under conditions close to nature. Capillary electrophoresis (CE, Beckman Coulter P/ACE MDQ), with its excellent separation performance, was coupled to Inductively Coupled Plasma Mass Spectrometry (ICP-MS, VG Elemental Plasma Quad 3) to obtain a high sensitivity for the determination of the rare earth elements europium (Eu{sup 3+}) and gadolinium (Gd{sup 3+}) and their complexes with humic acid. Additionally, the used humic acid was halogenated with iodine as ICP-MS marker. A fused-silica capillary was flexibly fitted into a MicroMist 50 {mu}l nebulizer with a Cinnabar cyclonic spray chamber. The chamber was chilled to a temperature of 4 deg. C for best sensitivity. 200 ppb of caesium were added to the CE separation buffer to observe the capillary flow. A make-up fluid including 4 ppb Ho as an internal standard was combined with the flow from the capillary within the interface to obtain a fluid throughput high enough to maintain a continuous nebulization. Very low detection limits were achieved, 100 ppt for {sup 153}Eu and 125 ppt for {sup 158}Gd. With this optimized CE

  2. Treatment Results Of Diaphyseal Forearm Fractures With Dynamique Compression Plate A Retrospective study of 156 Cases.

    Directory of Open Access Journals (Sweden)

    Hassan BOUSSAKRI

    2016-03-01

    Full Text Available This retrospective study addresses a series of 156 cases of forearm fractures. These 156 cases were managed in the trauma-orthopedic department (B4 of Fez University Hospital, Morocco, from May 2008 till January 2013. The purpose of this study is to analyze epidemiological and clinical factors of diaphyseal forearm fractures and the results of their treatment with dynamic compression plate (DCP, as well as the complications and therapeutic errors of this surgical technique. The frequency of hospitalization in the trauma-orthopedic department was 3,96%. Ages ranged between 16 and 83, the average age was 32. 132 patients were male (85%. 90% were managed at the day of trauma. Traffic accidents were the most frequent cause in 52% patients. The fracture was in the left forearm in 65% of patients. 53% of fracture lines were in the middle third of the forearm. 38 fractures were open, and 30 were admitted for polytrauma. Osteosynthesis was performed with dynamic compression plate for all patients. In comparison with the literature, our series shows the predominance of young male patients, with traffic accidents being the cause. Osteosynthesis with dynamic compression plate remains the treatment of choice that provides satisfactory results if the accuracy in this technique was respected.

  3. Temperature effects on the interaction mechanisms between the europium (III) and uranyl ions and zirconium diphosphate; Effets de la temperature sur les mecanismes d'interaction entre les ions europium (3) et uranyle et le diphosphate de zirconium

    Energy Technology Data Exchange (ETDEWEB)

    Finck, N

    2006-10-15

    Temperature should remain higher than 25 C in the near field environment of a nuclear waste repository for thousands years. In this context, the aim of this work is to study the temperature influence on the interaction mechanisms between europium (III) and uranyl ions and zirconium diphosphate, as well as the influence of a complexing medium (nitrate) on the sorption of the lanthanide. The experimental definition of the equilibria was achieved by combining a structural investigation with the macroscopic sorption data. Surface complexes were characterized at all temperatures (25 C to 90 C) by TRLFS experiments carried out on dry and in situ samples using an oven. This characterization was completed by XPS experiments carried out at 25 C on samples prepared at 25 C and 90 C. The reaction constants (surface hydration and cations sorption) were obtained by simulating the experimental data with the constant capacitance surface complexation model. The reaction constants temperature dependency allowed one to characterize thermodynamically the different reactions by application of the van't Hoff relation. The validity of this law was tested by performing microcalorimetric measurements of the sorption heat for both cations. (author)

  4. Quantum dot based on tin/titanium mixed oxide doped with europium synthesized by protein sol-gel method

    Energy Technology Data Exchange (ETDEWEB)

    Paganini, Paula P.; Felinto, Maria Claudia F.C., E-mail: paulapaganini@usp.b, E-mail: mfelinto@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Brito, Hermi F., E-mail: hefbrito@iq.usp.b [Universidade de Sao Paulo (IQ/USP), Sao Paulo, SP (Brazil). Inst. de Quimica. Lab. de Elementos do Bloco f

    2011-07-01

    Special luminescence biomarkers have been developed to find more sensitive fluoroimmunoassay methods. A new generation of these biomarkers is the semiconductors nanocrystals, known as quantum dots, doped with lanthanides. The use of lanthanides ions as luminescent markers has many advantages, for example a security method, low cost, high specificity and also the luminescence can be promptly measured with high sensibility and accuracy. The protein sol-gel is a modification of conventional method, in which the coconut water replacing the alkoxides normally used. The advantage is that, the proteins present in coconut water bind chemically with metal salts forming a polymer chain. This work presents nanoparticles based on tin/titanium mixed oxide doped with 3% of europium synthesized by protein sol-gel method. The nanoparticles were burned at 300 deg C, 500 deg C, 800 deg C and 1100 deg C. The samples were analyzed and characterized by thermal analysis, X-ray powder diffraction (XRD), infrared spectroscopy (IR) and scanning electron microscopy (SEM). The synthesis was effective and the nanoparticles showed nanometric size and structural differences with the annealing. To be used in the fluoroimmunoassays tests, these particles need to be functionalized before be connect with biological molecules and after this process, these nanoparticles going to be submitted at gamma radiation for sterilization. (author)

  5. 340nm UV LED excitation in time-resolved fluorescence system for europium-based immunoassays detection

    Science.gov (United States)

    Rodenko, Olga; Fodgaard, Henrik; Tidemand-Lichtenberg, Peter; Pedersen, Christian

    2017-02-01

    In immunoassay analyzers for in-vitro diagnostics, Xenon flash lamps have been widely used as excitation light sources. Recent advancements in UV LED technology and its advantages over the flash lamps such as smaller footprint, better wall-plug efficiency, narrow emission spectrum, and no significant afterglow, have made them attractive light sources for gated detection systems. In this paper, we report on the implementation of a 340 nm UV LED based time-resolved fluorescence system based on europium chelate as a fluorescent marker. The system performance was tested with the immunoassay based on the cardiac marker, TnI. The same signal-to-noise ratio as for the flash lamp based system was obtained, operating the LED below specified maximum current. The background counts of the system and its main contributors were measured and analyzed. The background of the system of the LED based unit was improved by 39% compared to that of the Xenon flash lamp based unit, due to the LEDs narrower emission spectrum and longer pulse width. Key parameters of the LED system are discussed to further optimize the signal-to-noise ratio and signal-to-background, and hence the sensitivity of the instrument.

  6. Interaction of europium and nickel with calcite studied by Rutherford Backscattering Spectrometry and Time-Resolved Laser Fluorescence Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sabau, A. [Agence Nationale pour la gestion des Déchets RAdioactifs, 1-7 rue J. Monnet, Parc de la Croix Blanche, 92298 Châtenay-Malabry Cedex (France); Université de Nice Sophia Antipolis, Ecosystèmes Côtiers Marins et Réponses aux Stress (ECOMERS), 28 avenue Valrose, 06108 Nice Cedex 2 (France); Pipon, Y., E-mail: pipon@ipnl.in2p3.fr [Institut de Physique Nucléaire de Lyon (IPNL), Université Lyon 1, CNRS/IN2P3, 4 rue Enrico Fermi, 69 622 Villeurbanne Cedex (France); Institut Universitaire de Technologie (IUT) Lyon-1, Université Claude Bernard Lyon 1, 69 622 Villeurbanne Cedex (France); Toulhoat, N. [Institut de Physique Nucléaire de Lyon (IPNL), Université Lyon 1, CNRS/IN2P3, 4 rue Enrico Fermi, 69 622 Villeurbanne Cedex (France); CEA/DEN, Saclay, 91191 Gif sur Yvette (France); Lomenech, C. [Université de Nice Sophia Antipolis, Ecosystèmes Côtiers Marins et Réponses aux Stress (ECOMERS), 28 avenue Valrose, 06108 Nice Cedex 2 (France); Jordan, N. [Helmholtz Zentrum Dresden Rossendorf (HZDR), Institute of Resource Ecology (IRE) (Germany); Moncoffre, N. [Institut de Physique Nucléaire de Lyon (IPNL), Université Lyon 1, CNRS/IN2P3, 4 rue Enrico Fermi, 69 622 Villeurbanne Cedex (France); Barkleit, A. [Helmholtz Zentrum Dresden Rossendorf (HZDR), Institute of Resource Ecology (IRE) (Germany); and others

    2014-08-01

    This study aims at elucidating the mechanisms regulating the interaction of Eu and Ni with calcite (CaCO{sub 3}). Calcite powders or single crystals (some mm sized) were put into contact with Eu or Ni solutions at concentrations ranging from 10{sup −3} to 10{sup −5} mol L{sup −1} for Eu and 10{sup −3} mol L{sup −1} for Ni. The sorption durations ranged from 1 week to 1 month. Rutherford Backscattering Spectrometry (RBS) well adapted to discriminate incorporation processes such as: (i) adsorption or co precipitation at the mineral surfaces or, (ii) incorporation into the mineral structure (through diffusion for instance), has been carried out. Moreover, using the fluorescence properties of europium, the results have been compared to those obtained by Time-Resolved Laser Fluorescence Spectroscopy (TRLFS) on calcite powders. For the single crystals, complementary SEM observations of the mineral surfaces at low voltage were also performed. Results showed that Ni accumulates at the calcite surface whereas Eu is also incorporated at a greater depth. Eu seems therefore to be incorporated into two different states in calcite: (i) heterogeneous surface accumulation and (ii) incorporation at depth greater than 160 nm after 1 month of sorption. Ni was found to accumulate at the surface of calcite without incorporation.

  7. Orange-red emitting europium doped strontium ortho-silicate phosphor prepared by a solid state reaction method.

    Science.gov (United States)

    Sahu, Ishwar Prasad

    2017-05-01

    In the present article we report europium-doped strontium ortho-silicates, namely Sr 2 SiO 4 :xEu 3+ (x = 1.0, 1.5, 2.0, 2.5 or 3.0 mol%) phosphors, prepared by solid state reaction method. The crystal structures of the sintered phosphors were consistent with orthorhombic crystallography with a Pmna space group. The chemical compositions of the sintered phosphors were confirmed by energy dispersive X-ray spectroscopy (EDS). Thermoluminescence (TL) kinetic parameters such as activation energy, order of kinetics and frequency factors were calculated by the peak shape method. Orange-red emission originating from the 5 D 0 - 7 F J (J = 0, 1, 2, 3) transitions of Eu 3+ ions could clearly be observed after samples were excited at 395 nm. The combination of these emissions constituted orange-red light as indicated on the Commission Internationale de l'Eclairage (CIE) chromaticity diagram. Mechanoluminescence (ML) intensity of the prepared phosphor increased linearly with increasing impact velocity of the moving piston that suggests that these phosphors can also be used as sensors to detect the stress of an object. Thus, the present investigation indicates that the piezo-electricity was responsible for producing ML in the prepared phosphor. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Application of Europium Multiwalled Carbon Nanotubes as Novel Luminophores in an Electrochemiluminescent Aptasensor for Thrombin Using Multiple Amplification Strategies.

    Science.gov (United States)

    Wu, Dan; Xin, Xia; Pang, Xuehui; Pietraszkiewicz, Marek; Hozyst, Robert; Sun, Xian'ge; Wei, Qin

    2015-06-17

    A novel electrochemiluminescent (ECL) aptasensor was proposed for the determination of thrombin (TB) using exonuclease-catalyzed target recycling and hybridization chain reaction (HCR) to amplify the signal. The capture probe was immobilized on an Au-GS-modified electrode through a Au-S bond. Subsequently, the hybrid between the capture probe and the complementary thrombin binding aptamer (TBA) was aimed at obtaining double-stranded DNA (dsDNA). The interaction between TB and its aptamer led to the dissociation of dsDNA because TB has a higher affinity to TBA than the complementary strands. In the presence of exonuclease, aptamer was selectively digested and TB could be released for target recycling. Extended dsDNA was formed through HCR of the capture probe and two hairpin DNA strands (NH2-DNA1 and NH2-DNA1). Then, numerous europium multiwalled carbon nanotubes (Eu-MWCNTs) could be introduced through amidation reaction between NH2-terminated DNA strands and carboxyl groups on the Eu-MWCNTs, resulting in an increased ECL signal. The multiple amplification strategies, including the amplification of analyte recycling and HCR, and high ECL efficiency of Eu-MWCNTs lead to a wide linear range (1.0×10(-12)-5.0×10(-9) mol/L) and a low detection limit (0.23 pmol/L). The method was applied to serum sample analysis with satisfactory results.

  9. Spectrophotometric Determination and Removal of Unchelated Europium Ions from Solutions Containing Eu-Diethylenetriaminepentaacetic Acid Chelate-Peptide Conjugates1

    Science.gov (United States)

    Dayan Elshan, N. G. R.; Patek, Renata; Vagner, Josef; Mash, Eugene A.

    2014-01-01

    Europium chelates conjugated with peptide ligands are routinely used as probes for conducting in vitro binding experiments. The presence of unchelated Eu ions in these formulations gives high background luminescence and can lead to poor results in binding assays. In our experience, the reported methods for purification of these probes do not achieve adequate removal of unchelated metal ions in a reliable manner. In this work, a xylenol orange-based assay for the quantification of unchelated metal ions was streamlined and used to determine levels of metal ion contamination, as well as the success of metal ion removal upon attempted purification. We compared the use of Empore™ chelating disks and Chelex® 100 resin for the selective removal of unchelated Eu ions from several Eu-diethylenetriaminepentaacetic acid chelate-peptide conjugates. Both purification methods gave complete and selective removal of the contaminant metal ions. However, Empore™ chelating disks were found to give much higher recoveries of the probes under the conditions utilized. Related to the issue of probe recovery, we also describe a significantly more efficient method for the synthesis of one such probe using Rink amide AM resin in place of Tentagel S resin. PMID:25058927

  10. Reusable temperature-sensitive luminescent material based on vitrified film of europium(III) β-diketonate complex

    Science.gov (United States)

    Lapaev, Dmitry V.; Nikiforov, Victor G.; Lobkov, Vladimir S.; Knyazev, Andrey A.; Galyametdinov, Yury G.

    2018-01-01

    We have proposed a novel temperature-sensitive luminescent material which is a 20 μm thick vitrified film (sandwiched between two quartz plates) fabricated from an amorphous powder of a mesogenic europium(III) β-diketonate complex through a melt-processing technique. The film photoexcited by a 337 nm pulsed nitrogen laser displays a typical Eu3+ ion luminescence bands with the strongest peak at 612 nm and with the decay time of 537 μs at 298 K. It is obtained that both the mean luminescence intensity and the luminescence decay time at 612 nm decrease significantly with temperature increasing from 298 to 348 K; the average values of the relative and absolute temperature sensitivities of the luminescence decay time in the range of 298-348 K are -1.2%·K-1 and -6.5 μs·K-1, respectively. The thermal quenching mechanism of the luminescent properties was analyzed and discussed. The experiments showed that, the luminescent properties of the film is insensitive to oxygen, the film is photostable under UV light, there is full reversibility of the temperature-dependent luminescence intensity and the decay time, and the high luminescence brightness of the film can be observed with violet light excitation. These factors indicated that the film is promising material for reusable luminescent thermometers, suitable for long-term monitoring in the range of 298-348 K.

  11. Differential ERK activation during autophagy induced by europium hydroxide nanorods and trehalose: Maximum clearance of huntingtin aggregates through combined treatment.

    Science.gov (United States)

    Wei, Peng-Fei; Jin, Pei-Pei; Barui, Ayan Kumar; Hu, Yi; Zhang, Li; Zhang, Ji-Qian; Shi, Shan-Shan; Zhang, Hou-Rui; Lin, Jun; Zhou, Wei; Zhang, Yun-Jiao; Ruan, Ren-Quan; Patra, Chitta Ranjan; Wen, Long-Ping

    2015-12-01

    Accelerating the clearance of intracellular protein aggregates through elevation of autophagy represents a viable approach for the treatment of neurodegenerative diseases. In our earlier report, we have demonstrated the enhanced degradation of mutant huntingtin protein aggregates through autophagy process induced by europium hydroxide nanorods [EHNs: Eu(III)(OH)3], but the underlying molecular mechanism of EHNs mediated autophagy was unclear. The present report reveals that EHNs induced autophagy does not follow the classical AKT-mTOR and AMPK signaling pathways. The inhibition of ERK1/2 phosphorylation using the specific MEK inhibitor U0126 partially abrogates the autophagy as well as the clearance of mutant huntingtin protein aggregates mediated by EHNs suggesting that nanorods stimulate the activation of MEK/ERK1/2 signaling pathway during autophagy process. In contrast, another mTOR-independent autophagy inducer trehalose has been found to induce autophagy without activating ERK1/2 signaling pathway. Interestingly, the combined treatment of EHNs and trehalose leads to more degradation of mutant huntingtin protein aggregates than that obtained with single treatment of either nanorods or trehalose. Our results demonstrate the rational that further enhanced clearance of intracellular protein aggregates, needed for diverse neurodegenerative diseases, may be achieved through the combined treatment of two or more autophagy inducers, which stimulate autophagy through different signaling pathways. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Synthesis of europium-doped VSOP, customized enhancer solution and improved microscopy fluorescence methodology for unambiguous histological detection.

    Science.gov (United States)

    de Schellenberger, Angela Ariza; Hauptmann, Ralf; Millward, Jason M; Schellenberger, Eyk; Kobayashi, Yuske; Taupitz, Matthias; Infante-Duarte, Carmen; Schnorr, Jörg; Wagner, Susanne

    2017-10-10

    Intrinsic iron in biological tissues frequently precludes unambiguous the identification of iron oxide nanoparticles when iron-based detection methods are used. Here we report the full methodology for synthesizing very small iron oxide nanoparticles (VSOP) doped with europium (Eu) in their iron oxide core (Eu-VSOP) and their unambiguous qualitative and quantitative detection by fluorescence. The resulting Eu-VSOP contained 0.7 to 2.7% Eu relative to iron, which was sufficient for fluorescent detection while not altering other important particle parameters such as size, surface charge, or relaxivity. A customized enhancer solution with high buffer capacity and nearly neutral pH was developed to provide an antenna system that allowed fluorescent detection of Eu-VSOP in cells and histologic tissue slices as well as in solutions even under acidic conditions as frequently obtained from dissolved organic material. This enhancer solution allowed detection of Eu-VSOP using a standard fluorescence spectrophotometer and a fluorescence microscope equipped with a custom filter set with an excitation wavelength (λex) of 338 nm and an emission wavelength (λem) of 616 nm. The fluorescent detection of Eu-doped very small iron oxide nanoparticles (Eu-VSOP) provides a straightforward tool to unambiguously characterize VSOP biodistribution and toxicology at tissue, and cellular levels, providing a sensitive analytical tool to detect Eu-doped IONP in dissolved organ tissue and biological fluids with fluorescence instruments.

  13. Efficient solution-processed double-layer red OLEDs based on a new europium complex with a carbazole group.

    Science.gov (United States)

    Liu, Jian; Miao, Jing-Sheng; Wu, Hong-Bin

    2015-06-01

    A new europium complex EuL3 (Phen) was used as guest dopant, and a blend of Polyvinylcarbazole and 2-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PVK and PBD) as host matrix. Efficient red organic light-emitting devices (OLEDs) with double-layer structures were manufactured via a solution-processed technique. The guest-doped levels were 1, 3 and 5 wt% relative to the blend mass, respectively. For the 1 wt% doping-level device, the luminous efficiency and luminance were up to 2.96 cd/A and 635.78 cd/m(2) with emissions from both EuL3 (Phen) and from the host; for the 3 wt% doping-level device, the maximum luminous efficiency and luminance were 1.01 cd/A and 370.91 cd/m(2) for the single emission from EuL3 (Phen) only. Copyright © 2014 John Wiley & Sons, Ltd.

  14. Europium Nanospheres-Based Time-Resolved Fluorescence for Rapid and Ultrasensitive Determination of Total Aflatoxin in Feed.

    Science.gov (United States)

    Wang, Du; Zhang, Zhaowei; Li, Peiwu; Zhang, Qi; Ding, Xiaoxia; Zhang, Wen

    2015-12-02

    Immunochromatographic (IC) assays are considered suitable diagnostic tools for the determination of mycotoxins. A europium nanospheres-based time-resolved fluorescence immunoassay (Eu-Nano-TRFIA), based on a monoclonal antibody and a portable TRFIA reader, was developed to determine total aflatoxin (including aflatoxins B1, B2, G1, and G2) levels in feed samples. Under optimized conditions, the Eu-Nano-TRFIA method detected total aflatoxin within 12 min. It showed good linearity (R(2) > 0.985), LOD of 0.16 μg/kg, a wide dynamic range of 0.48-30.0 μg/kg, recovery rates of 83.9-113.9%, and coefficients of variation (CVs) of 3.5-8.8%. In the 397 samples from company and livestock farms throughout China, the detection rate was 78.3%, concentrations were 0.50-145.30 μg/kg, the highest total aflatoxin content was found in cottonseed meal, and corn was found to be the most commonly contaminated feed. This method could be a powerful alternative for the rapid and ultrasensitive determination of total aflatoxin in quality control and meet the required Chinese maximum residue limits.

  15. Spectrophotometric determination and removal of unchelated europium ions from solutions containing Eu-diethylenetriaminepentaacetic acid chelate-peptide conjugates.

    Science.gov (United States)

    Elshan, N G R Dayan; Patek, Renata; Vagner, Josef; Mash, Eugene A

    2014-11-01

    Europium chelates conjugated with peptide ligands are routinely used as probes for conducting in vitro binding experiments. The presence of unchelated Eu ions in these formulations gives high background luminescence and can lead to poor results in binding assays. In our experience, the reported methods for purification of these probes do not achieve adequate removal of unchelated metal ions in a reliable manner. In this work, a xylenol orange-based assay for the quantification of unchelated metal ions was streamlined and used to determine levels of metal ion contamination as well as the success of metal ion removal on attempted purification. We compared the use of Empore chelating disks and Chelex 100 resin for the selective removal of unchelated Eu ions from several Eu-diethylenetriaminepentaacetic acid chelate-peptide conjugates. Both purification methods gave complete and selective removal of the contaminant metal ions. However, Empore chelating disks were found to give much higher recoveries of the probes under the conditions used. Related to the issue of probe recovery, we also describe a significantly more efficient method for the synthesis of one such probe using Rink amide AM resin in place of Tentagel S resin. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Formation and structural characterization of a europium(II mono(scorpionate complex and a sterically crowded pyrazabole

    Directory of Open Access Journals (Sweden)

    Phil Liebing

    2017-12-01

    Full Text Available The reaction of EuI2(THF2 with potassium hydrotris(3,5-diisopropylpyrazolylborate (K[HB(3,5-iPr2pz3] (= KTpiPr2, pz = pyrazolyl in a molar ratio of 1:1.5 resulted in extensive ligand fragmentation and formation of the europium(II mono(scorpionate complex bis(3,5-diisopropyl-1H-pyrazole[hydrotris(3,5-diisopropylpyrazolylborato]iodidoeuropium(II, [Eu(C27H46BN6I(C9H16N22] or (TpiPr2(3,5-iPr2pzH2EuIII, 1, in high yield (78%. As a typical by-product, small amounts of the sterically crowded pyrazabole derivative trans-4,8-bis(3,5-diisopropylpyrazol-1-yl-1,3,5,7-tetraisopropylpyrazabole, C36H62B2H8 or trans-{(3,5-iPr2pzHB(μ-3,5-iPr2pz}2, 2, were formed. Both title compounds have been structurally characterized through single-crystal X-ray diffraction. In 1, two isopropyl groups are each disordered over two orientations with occupancy ratios of 0.574 (10:0.426 (10 and 0.719 (16:0.281 (16. In 2, one isopropyl group is similarly disordered, occupancy ratio 0.649 (9:0.351 (9.

  17. Spectrofluorimetric study of the interaction between europium(III) and moxifloxacin in micellar solution and its analytical application

    Science.gov (United States)

    Kamruzzaman, Mohammad; Alam, Al-Mahmnur; Lee, Sang Hak; Ragupathy, Dhanusuraman; Kim, Young Ho; Park, Sang-Ryoul; Kim, Sung Hong

    2012-02-01

    A sensitive spectrofluorimetric method has been developed for the determination of moxifloxacin (MOX) using europium(III)-MOX complex as a fluorescence probe in the presence of an anionic surfactant, sodium dodecyl benzene sulfonate (SDBS). The fluorescence (FL) intensity of Eu 3+ was enhanced by complexation with MOX at 614 nm after excitation at 373 nm. The FL intensity of the Eu 3+-MOX complex was significantly intensified in the presence of SDBS. Under the optimum conditions, it was found that the enhanced FL intensity of the system showed a good linear relationship with the concentration of MOX over the range of 1.8 × 10 -11-7.3 × 10 -9 g mL -1 with a correlation coefficient of 0.9998. The limit of detection of MOX was found to be 2.8 × 10 -12 g mL -1 with relative standard deviation (RSD) of 1.25% for 5 replicate determination of 1.5 × 10 -8 g mL -1 MOX. The proposed method is simple, offers higher sensitivity with wide linear range and can be successfully applied to determine MOX in pharmaceutical and biological samples with good reproducibility. The luminescence mechanism is also discussed in detail with ultraviolet absorption spectra.

  18. Photoluminescence properties of europium doped di-strontium magnesium di-silicate phosphor by solid state reaction method

    Directory of Open Access Journals (Sweden)

    Ishwar Prasad Sahu

    2015-01-01

    Full Text Available Europium doped di-strontium magnesium di-silicate phosphor namely (Sr2MgSi2O7:Eu3+ was prepared by the traditional high temperature solid state reaction method. The phase structure of sintered phosphor was akermanite type structure which belongs to the tetragonal crystallography with space group P42¯1m, this structure is a member of the melilite group and forms a layered compound. The EDX and FTIR spectra confirm the present elements in Sr2MgSi2O7:Eu3+ phosphor. Photoluminescence measurements showed that the phosphor exhibited strong emission peak with good intensity, corresponding to 5D0 → 7F2 (613 nm red emission and weak 5D0 → 7F1 (590 nm orange emission. The excitation spectra monitored at 613 nm show broad band from 220 to 300 nm ascribed to O–Eu charge-transfer band (CTB centered at about 269 nm, and the other peaks in the range of 300–400 nm originated from f–f transitions of Eu3+ ions. The strongest band at 395 nm can be assigned to 7F0 / 5L6 transition of Eu3+ ions due to the typical f–f transitions within Eu3+ of 4f6 configuration.

  19. Highly selective luminescent sensing of picric acid based on a water-stable europium metal-organic framework

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Tifeng; Zhu, Fengliang; Cui, Yuanjing, E-mail: cuiyj@zju.edu.cn; Yang, Yu; Wang, Zhiyu; Qian, Guodong, E-mail: gdqian@zju.edu.cn

    2017-01-15

    A water-stable metal-organic framework (MOF) EuNDC has been synthesized for selective detection of the well-known contaminant and toxicant picric acid (PA) in aqueous solution. Due to the photo-induced electron transfer and self-absorption mechanism, EuNDC displayed rapid, selective and sensitive detection of PA with a detection limit of 37.6 ppb. Recyclability experiments revealed that EuNDC retains its initial luminescent intensity and same quenching efficiency in each cycle, suggesting high photostability and reusability for long-term sensing applications. The excellent detection performance of EuNDC makes it a promising PA sensing material for practical applications. - Graphical abstract: A water-stable europium-based metal-organic framework has been reported for highly selective sensing of picric acid (PA) with a detection limit of 37.6 ppb in aqueous solution. - Highlights: • A water-stable metal-organic framework (MOF) EuNDC was synthesized. • The highly selective detection of picric acid with a detection limit of 37.6 ppb was realized. • The detection mechanism were also presented and discussed.

  20. One-pot carbonization synthesis of europium-doped carbon quantum dots for highly selective detection of tetracycline

    Science.gov (United States)

    Li Liu, Meng; Chen, Bin Bin; Yang, Tong; Wang, Jian; Liu, Xi Dong; Zhi Huang, Cheng

    2017-03-01

    The detection of tetracycline is of great significance because of its damaging effects on human health, such as renal toxicity and hemolytic anemia. Any release of tetracycline into the surrounding environment can produce bacterial drug resistance. We develop a new sensitive and selective detection approach for tetracycline in complex water samples by preparing europium-doped carbon quantum dots (Eu-CQDs) through a simple and rapid carbonization method operating at 200 °C for 5 min. The Eu-CQDs are characterized by blue photoluminescence, excitation-wavelength-dependent emission and excellent stability. Importantly, the fluorescence of the Eu-CQDs can be quenched efficiently by tetracycline, based on the strong inner filter effect mechanism between Eu-CQDs and tetracycline, making the fluorescence intensity ratio (I 0/I) of the Eu-CQDs at 465 nm correlate linearly with the concentration of tetracycline in the range of 0.5-200 μM, with a limit of detection of 0.3 μM. This shows the broad applicability of the Eu-CQDs in pursuing the concepts of simplicity and specificity for analytical purposes.

  1. Mesoporous Europium-Doped Titania Nanoparticles (Eu-MTNs) for Luminescence-Based Intracellular Bio-Imaging.

    Science.gov (United States)

    Chen, Kuan-Chou; Dutta, Saikat; Yamauchi, Yusuke; Alshehri, Saad M; Nguyen, Mai Thanh; Yonezawa, Tetsu; Shen, Kun-Hung; Wu, Kevin C W

    2015-12-01

    Monodisperse and mesoporous europium (Eu)-doped titania nanoparticles (denoted as Eu-MTNs) were prepared by a co-synthesis method with the presence of a cationic surfactant (i.e., CTAB). A maximum loading amount of 8 mol% of Eu could be successfully incorporated into the framework of MTNs. The synthesized Eu-MTNs samples were characterized with X-ray diffraction (XRD) and scanning electron microscopy (SEM), with their luminescent property examined by photoluminescence (PL). Under ultraviolet irradiation, the Eu-MTNs samples exhibit several characteristic luminescence corresponding to 5D0-7F(j) for Eu+3 ions, which can be attributed to the energy transfer from titania nanocrystallite to Eu3+ ions dispersed in amorphous mesoporous titania region. The potential intracellular bio-imaging application of the synthesized Eu-MTN nanoparticles was demonstrated with a breast cancer cell line (i.e., BT-20). High biocompatibility and strong luminescence of the Eu-MTNs show great potential in biomedical applications.

  2. [Pulmonary function testing of 156 children exposed to automobile pollution in the municipality of Cotonou].

    Science.gov (United States)

    Messan, F; Lawani, M M; Marqueste, T; Lounana, J; Aimihoue, D; Metodakou, A; Decherchi, P; Grélot, L

    2011-01-01

    To evaluate the risk of disruption of distal airways in children exposed to pollutants automobiles. Study included 156 children selected assigned in groups "Most Exposed" and "Less Exposed" separated respectively 15 meters and 150 meters of road traffic. Children in both groups were subjected to lung function tests before and after an exercise test that was to perform a series of flexion / extension of the knees to the fatigue. FEV and MEF(25) were parameters selected. Change in FEV post exercise of each group is below 5%. The group "Less Exposed" presented a mean value of MEF(25) before exercise similar to that recorded after exercise. Within the group "Most Exposed", the mean value of MEF(25) post exercise is significantly lower than that observed at rest of 8.65%. The fact of living permanently near the traffic, poses serious risks of disruption of the distal airways.

  3. Wheat related allergy – A retrospective single-centre study of 156 patient

    DEFF Research Database (Denmark)

    Junker Christensen, Morten

    2014-01-01

    Background Allergy to wheat can manifest in different forms: sensitization to ingested wheat via the gastrointestinal tract can cause traditional food allergy or in combination with exercise, Wheat-Dependent Exercise-Induced Anaphylaxis (WDEIA). Sensitization to inhaled wheat flour may lead...... to occupational rhinitis and/or asthma. Methods We retrospectively investigated 156 patients (age 0.7 – 73 years) with a case history of wheat allergy. The population was divided into three groups, I: wheat allergy elicited by ingestion of wheat, II: by inhalation and III: WDEIA. All were examined with detailed...... case history, specific IgE (s-IgE), (Thermofischer AB, Sweden), Skin Prick Test (SPT) and wheat challenge (nasal or oral ± exercise). Results Group I: Twenty one of 95 patients were challenge positive (15 children, 6 adults). All positive children had atopic dermatitis and 90 % also other food...

  4. The europium and praseodymium hydrolysis in a 2M NaCl environment; La hidrolisis del europio y del praseodimio en un medio 2M de NaCl

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez R, M.; Lopez G, H.; Solache R, M.; Rojas H, A. [Instituto Nacional de Investigaciones Nucleares, Departamento de quimica, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1998-07-01

    It was studied the europium and praseodymium hydrolysis in a 2M NaCl ion force environment at 303 K, through two methods: this one extraction with dissolvents (lanthanide-water-NaCl-dibenzoylmethane) in presence of a competitive ligand (diglycolic acid) and that one direct potentiometric titration, of soluble species, followed by a computer refining. The values of one or another techniques of the first hydrolysis constants obtained were similar, which demonstrates that the results are reliable. The set of data obtained on the stability constants of hydrolysis products allowed to draw up the distribution diagrams of chemical species, as europium as praseodymium in aqueous environment. (Author)

  5. Specific chiral sensing of amino acids using induced circularly polarized luminescence of bis(diimine)dicarboxylic acid europium(III) complexes.

    Science.gov (United States)

    Okutani, Kazuhiro; Nozaki, Koichi; Iwamura, Munetaka

    2014-06-02

    The circularly polarized luminescence (CPL) from [Eu(pda)2](-) (pda = 1,10-phenanthroline-2,9-dicarboxylic acid) and [Eu(bda)2](-) (bda = 2,2'-bipyridine-6,6'-dicarboxylic acid) in aqueous solutions containing various amino acids was investigated. The europium(III) complexes exhibited bright-red luminescence assignable to the f-f transition of the Eu(III) ion when irradiated with UV light. Although the luminescence was not circularly polarized in the solid state or in aqueous solutions, in accordance with the achiral crystal structure, the complexes exhibited detectable induced CPL (iCPL) in aqueous solutions containing chiral amino acids. In the presence of L-pyrrolidonecarboxylic acid, both [Eu(pda)2](-) and [Eu(bda)2](-) showed similar iCPL intensity (glum ∼ 0.03 for the (5)D0 → (7)F1 transition at 1 mol·dm(-3) of the amino acid). On the other hand, in the presence of L-histidine or L-arginine, [Eu(pda)2](-) exhibited intense CPL (glum ∼ 0.08 for the (5)D0 → (7)F1 transition at 0.10 mol·dm(-3) of the amino acid), whereas quite weak CPL was observed for [Eu(bda)2](-) under the same conditions (glum europium(III) complexes possess coordination structures similar to that in the crystal with slight distortion to form a chiral structure due to specific interaction with two zwitterionic amino acids. This mechanism was in stark contrast to that of the europium(III) complex-pyrrolidonecarboxylic acid system in which one amino acid coordinates to the Eu(III) ion to yield an achiral coordination structure.

  6. A convenient method for europium-labeling of a recombinant chimeric relaxin family peptide R3/I5 for receptor-binding assays.

    Science.gov (United States)

    Zhang, Wei-Jie; Jiang, Qian; Wang, Xin-Yi; Song, Ge; Shao, Xiao-Xia; Guo, Zhan-Yun

    2013-06-01

    Relaxin family peptides have important biological functions, and so far, four G-protein-coupled receptors have been identified as their receptors (RXFP1-4). A chimeric relaxin family peptide R3/I5, containing the B-chain of relaxin-3 and the A-chain of INSL5, is a selective agonist for both RXFP3 and RXFP4. In a previous study, europium-labeled R3/I5, as a nonradioactive and low-background receptor-binding tracer, was prepared through a chemical synthesis approach. In the present study, we established a convenient alternative approach for preparing the europium-labeled R3/I5 tracer based on a recombinant R3/I5 designed to carry a solubilizing tag at the A-chain N-terminus and a pyroglutamate residue at the B-chain N-terminus. Because of the presence of a single primary amine moiety, the recombinant R3/I5 peptide was site-specifically mono-labeled at the A-chain N-terminus by a diethylenetriaminepentaacetic acid/europium moiety through a convenient one-step procedure. The diethylenetriaminepentaacetic acid/Eu3+-labeled R3/I5 bound both receptors RXFP3 and RXFP4 with high binding affinities and low nonspecific binding. Thus, we have presented a valuable nonradioactive tracer for future interaction studies on RXFP3 and RXFP4 with various natural or designed ligands. The present approach could also be adapted for preparing and labeling of other chimeric relaxin family peptides. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.

  7. Gradual Increase of miR156 Regulates Temporal Expression Changes of Numerous Genes during Leaf Development in Rice1[C][W][OA

    Science.gov (United States)

    Xie, Kabin; Shen, Jianqiang; Hou, Xin; Yao, Jialing; Li, Xianghua; Xiao, Jinghua; Xiong, Lizhong

    2012-01-01

    The highly conserved plant microRNA, miR156, is an essential regulator for plant development. In Arabidopsis (Arabidopsis thaliana), miR156 modulates phase changing through its temporal expression in the shoot. In contrast to the gradual decrease over time in the shoot (or whole plant), we found that the miR156 level in rice (Oryza sativa) gradually increased from young leaf to old leaf after the juvenile stage. However, the miR156-targeted rice SQUAMOSA-promoter binding-like (SPL) transcription factors were either dominantly expressed in young leaves or not changed over the time of leaf growth. A comparison of the transcriptomes of early-emerged old leaves and later-emerged young leaves from wild-type and miR156 overexpression (miR156-OE) rice lines found that expression levels of 3,008 genes were affected in miR156-OE leaves. Analysis of temporal expression changes of these genes suggested that miR156 regulates gene expression in a leaf age-dependent manner, and miR156-OE attenuated the temporal changes of 2,660 genes. Interestingly, seven conserved plant microRNAs also showed temporal changes from young to old leaves, and miR156-OE also attenuated the temporal changes of six microRNAs. Consistent with global gene expression changes, miR156-OE plants resulted in dramatic changes including precocious leaf maturation and rapid leaf/tiller initiation. Our results indicate that another gradient of miR156 is present over time, a gradual increase during leaf growth, in addition to the gradual decrease during shoot growth. Gradually increased miR156 expression in the leaf might be essential for regulating the temporal expression of genes involved in leaf development. PMID:22271747

  8. E0 decay of the 0{sup +}{sub 2} levels in {sup 156}Dy and {sup 160}Er

    Energy Technology Data Exchange (ETDEWEB)

    Lo Bianco, G; Nardelli, S; Gupta, S Das; Saltarelli, A [School of Science and Technology, University of Camerino and INFN - Sez. Perugia (Italy); Balabanski, D L [INRNE, Bulgarian Academy of Sciences, Sofia (Bulgaria); Blasi, N [INFN - Sez. Milano (Italy); Gladnishki, K [Faculty of Physics, St. Kliment Ohridski University of Sofia (Bulgaria); Fortunato, L, E-mail: balabanski@inrne.bas.b [ECT, Trento (Italy)

    2011-01-01

    The branching between the E0 0{sup +}{sub 2} {yields} 0{sup +}{sub 1} and the E2 0{sup +}{sub 2} {yields} 2{sup +}{sub 2} transitions in {sup 156}Dy and {sup 160}Er were measured following the {epsilon} decay of {sup 156}Ho and {sup 160}Tm. A potential of the 4th order of the deformation parameter {beta}, the {sup L}o Bianco potential{sup ,} was chosen to describe the U(5) - SU(3) first order shape phase transition, covering the whole transitional path. The comparison of the excitation spectra and the measured ratios of reduced transition probabilities, X(E0/E2), with the calculations, indicates that {sup 156}Dy is in the spherical region, while {sup 160}Er is located in the deformed region, but quite close to the critical point.

  9. Europium-activated phosphors containing oxides of rare-earth and group-IIIB metals and method of making the same

    Science.gov (United States)

    Comanzo, Holly Ann; Setlur, Anant Achyut; Srivastava, Alok Mani; Manivannan, Venkatesan

    2004-07-13

    Europium-activated phosphors comprise oxides of at least a rare-earth metal selected from the group consisting of gadolinium, yttrium, lanthanum, and combinations thereof and at least a Group-IIIB metal selected from the group consisting of aluminum, gallium, indium, and combinations thereof. A method for making such phosphors comprises adding at least a halide of at least one of the selected Group-IIIB metals in a starting mixture. The method further comprises firing the starting mixture in an oxygen-containing atmosphere. The phosphors produced by such a method exhibit improved absorption in the UV wavelength range and improved quantum efficiency.

  10. Synthesis and pharmacological characterization of a europium-labelled single-chain antagonist for binding studies of the relaxin-3 receptor RXFP3.

    Science.gov (United States)

    Haugaard-Kedström, Linda M; Wong, Lilian L L; Bathgate, Ross A D; Rosengren, K Johan

    2015-06-01

    Relaxin-3 and its endogenous receptor RXFP3 are involved in fundamental neurological signalling pathways, such as learning and memory, stress, feeding and addictive behaviour. Consequently, this signalling system has emerged as an attractive drug target. Development of leads targeting RXFP3 relies on assays for screening and ligand optimization. Here, we present the synthesis and in vitro characterization of a fluorescent europium-labelled antagonist of RXFP3. This ligand represents a cheap and safe but powerful tool for future mechanistic and cell-based receptor-ligand interaction studies of the RXFP3 receptor.

  11. Bis{[6-methoxy-2-(4-methylphenyliminiomethyl]phenolate-κ2O,O′}tris(nitrato-κ2O,O′europium(III

    Directory of Open Access Journals (Sweden)

    Hang-Ming Guo

    2010-11-01

    Full Text Available The crystal structure of title compound, [Eu(NO33(C15H15NO22], contains two Schiff base 6-methoxy-2-[(4-methylphenyliminomethyl]phenolate (L ligands and three independent nitrate ions that chelate to the europium(III ion via the O atoms. The coordination number of the EuIII ion is ten. The L ligands chelate with a strong Eu—O(deprotonated phenolate bond and a weak Eu—O(methoxy contact, the latter can be interpreted as the apices of the bicapped square-antiprismatic EuIII polyhedron. Intramolecular N—H...O hydrogen bonds occur.

  12. Carbon footprint assessment of recycling technologies for rare earth elements: A case study of recycling yttrium and europium from phosphor.

    Science.gov (United States)

    Hu, Allen H; Kuo, Chien-Hung; Huang, Lance H; Su, Chao-Chin

    2017-02-01

    Rare earth elements are key raw materials in high-technology industries. Mining activities and manufacturing processes of such industries have caused considerable environmental impacts, such as soil erosion, vegetation destruction, and various forms of pollution. Sustaining the long-term supply of rare earth elements is difficult because of the global shortage of rare earth resources. The diminishing supply of rare earth elements has attracted considerable concern because many industrialized countries regarded such elements as important strategic resources for economic growth. This study aims to explore the carbon footprints of yttrium and europium recovery techniques from phosphor. Two extraction recovery methods, namely, acid extraction and solvent extraction, were selected for the analysis and comparison of carbon footprints. The two following functional units were used: (1) the same phosphor amounts for specific Y and Eu recovery concentrations, and (2) the same phosphor amounts for extraction. For acid extraction method, two acidic solutions (H2SO4 and HCl) were used at two different temperatures (60 and 90°C). For solvent extraction method, acid leaching was performed followed by ionic liquid extraction. Carbon footprints from acid and solvent extraction methods were estimated to be 10.1 and 10.6kgCO2eq, respectively. Comparison of the carbon emissions of the two extraction methods shows that the solvent extraction method has significantly higher extraction efficiency, even though acid extraction method has a lower carbon footprint. These results may be used to develop strategies for life cycle management of rare earth resources to realize sustainable usage. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Europium doped di-calcium magnesium di-silicate orange–red emitting phosphor by solid state reaction method

    Directory of Open Access Journals (Sweden)

    Ishwar Prasad Sahu

    2015-07-01

    Full Text Available A new orange–red europium doped di-calcium magnesium di-silicate (Ca2MgSi2O7:Eu3+ phosphor was prepared by the traditional high temperature solid state reaction method. The prepared Ca2MgSi2O7:Eu3+ phosphor was characterized by X-ray diffractometer (XRD, transmission electron microscopy (TEM, field emission scanning electron microscopy (FESEM with energy dispersive x-ray spectroscopy (EDX, fourier transform infrared spectra (FTIR, photoluminescence (PL and decay characteristics. The phase structure of sintered phosphor was akermanite type structure which belongs to the tetragonal crystallography with space group P4¯21m, this structure is a member of the melilite group and forms a layered compound. The chemical composition of the sintered Ca2MgSi2O7:Eu3+ phosphor was confirmed by EDX spectra. The PL spectra indicate that Ca2MgSi2O7:Eu3+ can be excited effectively by near ultraviolet (NUV light and exhibit bright orange–red emission with excellent color stability. The fluorescence lifetime of Ca2MgSi2O7:Eu3+ phosphor was found to be 28.47 ms. CIE color coordinates of Ca2MgSi2O7:Eu3+ phosphor is suitable as orange-red light emitting phosphor with a CIE value of (X = 0.5554, Y = 0.4397. Therefore, it is considered to be a new promising orange–red emitting phosphor for white light emitting diode (LED application.

  14. Evaluation of in vivo cytogenetic toxicity of europium hydroxide nanorods (EHNs) in male and female Swiss albino mice.

    Science.gov (United States)

    Bollu, Vishnu Sravan; Nethi, Susheel Kumar; Dasari, Rama Krishna; Rao, Soma Shiva Nageshwara; Misra, Sunil; Patra, Chitta Ranjan

    2016-01-01

    Our group already demonstrated that europium hydroxide nanorods (EHNs) show none or mild toxicity in C57BL/6 mice even at high dose and exhibited excellent pro-angiogenic activity towards in vitro and in vivo models. In the present study, we evaluated the in vivo cytogenetic toxicity of intraperitoneally administered EHNs (12.5-250 mg/kg/b.w.) in male and female Swiss albino mice by analyzing chromosomal aberrations (CAs), mitotic index (MI), micronucleus (MN) from bone marrow and peripheral blood. Furthermore, we performed the cytogenetic toxicity study of EHNs towards Chinese hamster ovary (CHO) cells, in order to compare with the in vivo results. The results of CA assay of mice treated with EHNs (12.5-125 mg/kg/b.w.) showed no significant change in the formation of aberrant metaphases compared to the control group. Also, there was no significant difference in the number of dividing cells between the control group and EHNs-treated groups observed by MI study, suggesting the non-cytotoxicity of EHNs. Additionally, FACS study revealed that EHNs do not arrest cells at any phase of cell cycle in the mouse model. Furthermore, MN test of both bone marrow and peripheral blood showed no significant differences in the induction of MNs when compared with the control group. In vitro results from CHO cells also support our in vivo observations. Considering the role of angiogenesis by EHNs and the absence of its genotoxicity in mouse model, we strongly believe the future application of EHNs in treating various diseases, where angiogenesis plays an important role such as cardiovascular diseases, ischemic diseases and wound healing.

  15. Synthesis, characterization, crystal structure, DNA/BSA binding ability and antibacterial activity of asymmetric europium complex based on 1,10- phenanthroline

    Science.gov (United States)

    Alfi, Nafiseh; Khorasani-Motlagh, Mozhgan; Rezvani, Ali Reza; Noroozifar, Meissam; Molčanov, Krešimir

    2017-06-01

    A heteroleptic europium coordination compound formulated as [Eu(phen)2(OH2)2(Cl)2](Cl)(H2O) (phen = 1,10-phenanthroline), has been synthesized and characterized by elemental analysis, FT-IR spectroscopy, and single-crystal X-ray diffractometer. Crystal structure analysis reveals the complex is crystallized in orthorhombic system with Pca21 space group. Electronic absorption and various emission methods for investigation of the binding system of europium(III) complex to Fish Salmon deoxyribonucleic acid (FS-DNA) and Bovamin Serum Albumin (BSA) have been explored. Furthermore, the binding constants, binding sites and the corresponding thermodynamic parameters of the interaction system based on the van't Hoff equation for FS-DNA and BSA were calculated. The thermodynamic parameters reflect the exothermic nature of emission process (ΔH°DNA by non-intercalative mode which the groove binding is preferable mode. Also, the complex exhibits a brilliant antimicrobial activity in vitro against standard bacterial strains.

  16. Investigation on the co-luminescence effect of europium (III)-lanthanum(III)-dopamine-sodium dodecylbenzene sulfonate system and its application.

    Science.gov (United States)

    Si, Hailin; Zhao, Fang; Cai, Huan

    2013-01-01

    A novel luminescence, enhancement phenomenon in the europium(III)-dopamine-sodium dodecylbenzene sulfonate system was observed when lanthanum(III) was added. Based on this, a sensitive co-luminescence method was established for the determination of dopamine. The luminescence signal for the europium (III)-lanthanum(III)-dopamine-sodium dodecylbenzene sulfonate system was monitored at λ(ex) = 300 nm, λ(em) = 618 nm and pH 8.3. Under optimized conditions, the enhanced luminescence signal responded linearly to the concentration of dopamine in the range 1.0 × 10(-10)-5.0 × 10(-7) mol/L with a correlation coefficient of 0.9993 (n = 11). The detection limit (3σ) was 2.7 × 10(-11) mol/L and the relative standard deviation for 11 parallel measurements of 3.0 × 10(-8) mol/L dopamine was 1.9%. The presented method was successfully applied for the estimation of dopamine in samples of pharmaceutical preparations, human serum and urine. The possible luminescence enhancement mechanism of the system is discussed briefly. Copyright © 2013 John Wiley & Sons, Ltd.

  17. Europium-phenolic network coated BaGdF5 nanocomposites for tri-modal computed tomography/magnetic resonance/luminescence imaging.

    Science.gov (United States)

    Zhu, Wei; Liang, Shuang; Wang, Jing; Yang, Zhe; Zhang, Li; Yuan, Tianmeng; Xu, Zushun; Xu, Haibo; Li, Penghui

    2017-05-01

    Multifunctional nanocomposites based on BaGdF5 nanoparticles (NPs) and metal phenolic network (MPN) have been engineered as novel contrast agents for potential applications in X-ray computed tomography, magnetic resonance and luminescence imaging. The BaGdF5@MPN nanocomposites were synthesized at room temperature by coating BaGdF5 NPs with europium-phenolic network, which was obtained by the coordination of europium (III) with tannic acid (TA). The in vitro cytotoxicity assays against HepG2 cells revealed that the BaGdF5@MPN nanocomposites presented better cytocompatibility and lower cytotoxity than pure BaGdF5 NPs. In addition, vivid red and green luminescence can be observed by confocal laser scanning microscope (CLSM) from the BaGdF5@MPN nanocomposites laden HepG2 cells under the excitation of UV (390 nm) and visible light (440 nm), respectively. The longitudinal relaxivity value (r1) of the nanocomposites was 2.457 mM-1s-1. Moreover, the nanocomoposites exhibited X-ray computed tomography (CT) and T1-weighted magnetic resonance (MR) imaging capacities, and the intensities of the enhanced signals of in vitro CT and MR images were proportional to the concentrations of the nanocomposites. These results indicated that the as-prepared BaGdF5@MPN nanocomposites are promising contrast agents for CT/MR/luminescence imaging.

  18. Effective visible light-active boron and europium co-doped BiVO4 synthesized by sol-gel method for photodegradion of methyl orange.

    Science.gov (United States)

    Wang, Min; Che, Yinsheng; Niu, Chao; Dang, Mingyan; Dong, Duo

    2013-11-15

    Eu-B co-doped BiVO4 visible-light-driven photocatalysts have been synthesized using the sol-gel method. The resulting materials were characterized by a series of joint techniques, including XPS, XRD, SEM, BET, and UV-vis DRS analyses. Compared with BiVO4 and B-BiVO4 photocatalysts, the Eu-B-BiVO4 photocatalysts exhibited much higher photocatalytic activity for methyl orange (MO) degradation under visible light irradiation. The optimal Eu doping content is 0.8 mol%. It was revealed that boron and europium were doped into the lattice of BiVO4 and this led to more surface oxygen vacancies, high specific surface areas, small crystallite size, a narrower band gap and intense light absorbance in the visible region. The doped Eu(III) cations can help in the separation of photogenerated electrons. The synergistic effects of boron and europium in doped BiVO4 were the main reason for improving visible light photocatalytic activity. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Emission tunability and local environment in europium-doped OH{sup −}-free calcium aluminosilicate glasses for artificial lighting applications

    Energy Technology Data Exchange (ETDEWEB)

    Farias, Aline M.; Sandrini, Marcelo; Viana, José Renato M.; Baesso, Mauro L.; Bento, Antônio C.; Rohling, Jurandir H. [Departamento de Física, Universidade Estadual de Maringá, Av Colombo, 5790, 87020-900, Maringá, PR (Brazil); Guyot, Yannick [Laboratoire de Physico–Chimie des Matériaux Luminescents, Université de Lyon, Université Claude Bernard Lyon 1, Villeurbanne, UMR 5620 CNRS 69622 (France); De Ligny, Dominique [Department of Materials Science and Engineering, University of Erlangen Nürnberg, Martens str. 5, 91058, Erlangen (Germany); Nunes, Luiz Antônio O. [Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador São-Carlense400, 13566-590, São Carlos, SP (Brazil); Gandra, Flávio G. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, 13083-859, Campinas, SP (Brazil); Sampaio, Juraci A. [Lab Ciências Físicas, Universidade Estadual Norte Fluminense, 28013-602, Campos Dos Goytacazes, RJ (Brazil); Lima, Sandro M.; Andrade, Luis Humberto C. [Grupo de Espectroscopia Óptica e Fototérmica, Universidade Estadual de Mato Grosso do Sul-UEMS, Dourados, MS, C. P. 351, CEP 79804-970 (Brazil); and others

    2015-04-15

    The relationship between emission tunability and the local environment of europium ions in OH{sup −}-free calcium aluminosilicate glasses was investigated, focusing on the development of devices for artificial lighting. Significant conversion of Eu{sup 3+} to Eu{sup 2+} was obtained by means of melting the glasses under a vacuum atmosphere and controlling the silica content, resulting in broad, intense, and tunable luminescence ranging from blue to red. Electron spin resonance and X-ray absorption near edge structure measurements enabled correlation of the luminescence behavior of the material with the Eu{sup 2+}/Eu{sup 3+} concentration ratio and changes in the surrounding ions' crystal field. The coordinates of the CIE 1931 chromaticity diagram were calculated from the spectra, and the contour maps showed that the light emitted from Eu{sup 2+} presented broad bands and enhanced color tuning, ranging from reddish-orange to blue. The results showed that these Eu doped glasses can be used for tunable white lighting by combining matrix composition and the adjustment of the pumping wavelength. - Highlights: • Eu{sup 2+}-doped OH{sup −} free calcium aluminosilicate glass as a new source for white lighting. • Correlation between emission tunability and local environment of europium ions. • Significant reduction of Eu{sup 3+} to Eu{sup 2+} by melting the glasses under vacuum atmosphere. • Broad, intense and tunable luminescence ranging from blue to red.

  20. International distribution and age estimation of the Portuguese BRCA2 c.156_157insAlu founder mutation

    NARCIS (Netherlands)

    Peixoto, Ana; Santos, Catarina; Pinheiro, Manuela; Pinto, Pedro; Soares, Maria Jose; Rocha, Patricia; Gusmao, Leonor; Amorim, Antonio; van der Hout, Annemarie; Gerdes, Anne-Marie; Thomassen, Mads; Kruse, Torben A.; Cruger, Dorthe; Sunde, Lone; Bignon, Yves-Jean; Uhrhammer, Nancy; Cornil, Lucie; Rouleau, Etienne; Lidereau, Rosette; Yannoukakos, Drakoulis; Pertesi, Maroulio; Narod, Steven; Royer, Robert; Costa, Mauricio M.; Lazaro, Conxi; Feliubadalo, Lidia; Grana, Begona; Blanco, Ignacio; de la Hoya, Miguel; Caldes, Trinidad; Maillet, Philippe; Benais-Pont, Gaelle; Pardo, Bruno; Laitman, Yael; Friedman, Eitan; Velasco, Eladio A.; Duran, Mercedes; Miramar, Maria-Dolores; Rodriguez Valle, Ana; Calvo, Maria-Teresa; Vega, Ana; Blanco, Ana; Diez, Orland; Gutierrez-Enriquez, Sara; Balmana, Judith; Ramon y Cajal, Teresa; Alonso, Carmen; Baiget, Montserrat; Foulkes, William; Tischkowitz, Marc; Kyle, Rachel; Sabbaghian, Nelly; Ashton-Prolla, Patricia; Ewald, Ingrid P.; Rajkumar, Thangarajan; Mota-Vieira, Luisa; Giannini, Giuseppe; Gulino, Alberto; Achatz, Maria I.; Carraro, Dirce M.; de Paillerets, Brigitte Bressac; Remenieras, Audrey; Benson, Cindy; Casadei, Silvia; King, Mary-Claire; Teugels, Erik; Teixeira, Manuel R.

    The c.156_157insAlu BRCA2 mutation has so far only been reported in hereditary breast/ovarian cancer (HBOC) families of Portuguese origin. Since this mutation is not detectable using the commonly used screening methodologies and must be specifically sought, we screened for this rearrangement in a

  1. Forensic potential of the STR DXYS156 in Mexican populations: inference of X-linked allele null.

    Science.gov (United States)

    Torres-Rodríguez, M; Martínez-Cortes, G; Páez-Riberos, L A; Sandoval, L; Muñoz-Valle, J F; Ceballos-Quintal, J M; Pinto-Escalante, D; Rangel-Villalobos, H

    2006-01-01

    The pentanucleotide STR (TAAAA)n DXYS156 offers advantages for genetic identity testing. In addition to establish the gender, DXYS156 expands the DNA profile and is able to indicate the possible geographic origin of the individual. We analyzed DXYS156 in 757 individuals of both sexes from Mexican populations. We studied the cosmopolitan Mestizo population and six Mexican ethnic groups: Tarahumaras, Purépechas, Nahuas, Mayas, Huicholes and Mezcala Indians. The six shorter (4-10) and the three larger alleles (11-13) were specific for the X and Y-chromosomes, respectively. A random distribution of alleles into genotypes was observed in males and females from each population. We estimated the power of exclusion for paternity testing according to the son's gender, and the power of discrimination in forensic casework. In addition, we detected a relatively high frequency of an X-linked allele null, principally in Mexican-Mestizos (3.6%), which must be considered when DXYS156 be applied for identification purposes.

  2. 76 FR 36578 - 156th Meeting of the Advisory Council on Employee Welfare and Pension Benefit Plans; Notice of...

    Science.gov (United States)

    2011-06-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employee Benefits Security Administration 156th Meeting of the Advisory Council on Employee Welfare and Pension... Council on Employee Welfare and Pension Benefit Plans; (also known as the ERISA Advisory Council) will be...

  3. Negative Regulation of Anthocynanin Biosynthesis in Arabidopsis by a miR156-Targeted SPL Transcription Factor

    Energy Technology Data Exchange (ETDEWEB)

    Gou, J.Y.; Liu, C.; Felippes, F. F.; Weigel, D.; Wang, J.-W.

    2011-04-01

    Flavonoids are synthesized through an important metabolic pathway that leads to the production of diverse secondary metabolites, including anthocyanins, flavonols, flavones, and proanthocyanidins. Anthocyanins and flavonols are derived from Phe and share common precursors, dihydroflavonols, which are substrates for both flavonol synthase and dihydroflavonol 4-reductase. In the stems of Arabidopsis thaliana, anthocyanins accumulate in an acropetal manner, with the highest level at the junction between rosette and stem. We show here that this accumulation pattern is under the regulation of miR156-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) genes, which are deeply conserved and known to have important roles in regulating phase change and flowering. Increased miR156 activity promotes accumulation of anthocyanins, whereas reduced miR156 activity results in high levels of flavonols. We further provide evidence that at least one of the miR156 targets, SPL9, negatively regulates anthocyanin accumulation by directly preventing expression of anthocyanin biosynthetic genes through destabilization of a MYB-bHLH-WD40 transcriptional activation complex. Our results reveal a direct link between the transition to flowering and secondary metabolism and provide a potential target for manipulation of anthocyanin and flavonol content in plants.

  4. 42 CFR 84.156 - Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Airflow resistance test; Type C supplied-air... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.156 Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements. (a) Inhalation resistance shall not...

  5. Magnetic states stabilization in Ni51Mn33.4In15.6 Heusler alloy

    Directory of Open Access Journals (Sweden)

    Mohammadreza Ghahremani

    2015-12-01

    Full Text Available The rate-independent stabilization of magnetic states with iterations in a Heusler alloy has been studied. The direct measurement of the adiabatic temperature change, ΔTad, of a Ni51Mn33.4In15.6 alloy near the magnetostructural phase transition is presented. The adiabatic temperature change at a given temperature within the temperature range of the magnetostructural transition is history dependent and varies considerably with the iteration count of the field cycle. The data show the transition from the low magnetization state to the high magnetization state during low to high (L–H temperature change direction and from high magnetization to low magnetization state during high to low (H–L temperature change direction require several field cycles to stabilize the ΔTad measurement, similar to the accommodation phenomenon in hysteretic materials. In the mixed magnetic state inside the first-order transition, both low and high magnetization portions of the alloy exist and it varies considerably with the induced fields. This original observation emphasizes that it is incorrect to assess the performance of a magnetic refrigeration system through a single measurement, and that achieving a stable, utilizable, adiabatic temperature change requires several field-induced transitions.

  6. Transplantation of rib cartilage reshaped with 1.56 μm laser radiation in rabbits

    Science.gov (United States)

    Sobol, E.; Baum, O.; Alexandrovskaya, Yu.; Shekhter, A.; Selezneva, L.; Svistuskin, V.

    2017-02-01

    As cartilage is an ideal natural material for transplantation, its use in the ENT surgery is limited by a difficulty to get proper shape of cartilage implants. Aim of the work is to make ring-shaped cartilage implants, to check their stability after laser reshaping and to perform transplantation into rabbits in vivo. We experimented with costal cartilages of 1-2 mm in thickness obtained from 3rd and 4rd ribs of a rabbit. 1.56 μm laser (Arcuo Medical Inc.) was used for cartilage reshaping. The laser settings were established taking into account anisotropy of cartilage structure for different orientation of the implants. The reshaped cartilage implants were surgically sewn to rib cartilages of the other rabbits. The rabbits were slaughtered in 3.5-4 months after surgery. The results have shown that (1) all reshaped implants kept circular form, and (2) the implants were adhered to the native rabbit cartilage sites (3) pronounced signs of regeneration in the intermediate zones were observed. The prospects of the cartilage implants use in larynx stenosis surgery are discussed.

  7. Determination of the hydrolysis constants of Europium (III), in ion strength media 4, 5 and 6 M NaClO{sub 4} at 303 K; Determinacion de las constantes de hidrolisis del Europio (III), en medios de fuerza ionica 4, 5 y 6 M de NaClO{sub 4} a 303 K

    Energy Technology Data Exchange (ETDEWEB)

    Alvarado B, A.; Jimenez R, M.; Solache R, M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    This work was made with the purpose to complete information about the hydrolysis constants of Europium (III) in high ion strength media. So it was determined at a ion forces media 4, 5 and 6 M of sodium perchlorate at 303 K. The method used was the potentiometric with the aid of the Super quad computer program. In high ion strength media, the measurements of p H do not correspond directly to negative logarithm of the concentration of hydrogen ions, by this it is necessary to calibrate the electrode in these conditions. The Europium was hydrolized at pC{sub H} values greater 6 in all cases. The potentiometric method used under the described experimental conditions is adequate to determine the hydrolysis constants of Europium (III). According to the results and diagrams of chemical species of Europium obtained we can conclude that the hydrolysis constants, differ by its distribution but not in its identity. (Author)

  8. The Level of Europium-154 Contaminating Samarium-153-EDTMP Activates the Radiation Alarm System at the US Homeland Security Checkpoints

    Directory of Open Access Journals (Sweden)

    Mohammed Najeeb Al Hallak

    2009-08-01

    Full Text Available 153Sm-EDTMP is a radiopharmaceutical composed of EDTMP (ethylenediamine-tetramethylenephosphonate and Samarium-153 [1]. 153Sm-EDTMP has an affinity for skeletal tissue and concentrates in areas with increased bone turnover; thus, it is successfully used in relieving pain related to diffuse bone metastases [1]. The manufacturing process of 153Sm-EDTMP leads to contamination with 154Eu (Europium-154 [2]. A previous study only alluded to the retention of 154Eu in the bones after receiving treatment with 153Sm-EDTMP [2]. Activation of the alarm at security checkpoints after 153Sm-EDTMP therapy has not been previously reported. Two out of 15 patients who received 153Sm-EDTMP at Roger Maris Cancer Center (Fargo, N. Dak., USA activated the radiation activity sensors while passing through checkpoints; one at a US airport and the other while crossing theAmerican-Canadian border. We assume that the 154Eu which remained in the patients’ bones activated the sensors. Methods: In order to investigate this hypothesis, we obtained the consent from 3 of our 15 patients who received 153Sm-EDTMP within the previous 4 months to 2 years, including the patient who had activated the radiation alarm at the airport. The patients were scanned with a handheld detector and a gamma camera for energies from 511 keV to 1.3 MeV. Results: All three patients exhibited identical spectral images, and further analysis showed that the observed spectra are the result of 154Eu emissions. Conclusion: Depending on the detection thresholds and windows used by local and federal authorities, the remaining activity of 154Eu retained in patients who received 153Sm-EDTMP could be sufficient enough to increase the count rates above background levels and activate the sensors. At Roger Maris Cancer Center, patients are now informed of the potential consequences of 153Sm-EDTMP therapy prior to initiating treatment. In addition, patients treated with 153Sm-EDTMP at Roger Maris Cancer Center

  9. Europium-Labeled Synthetic C3a Protein as a Novel Fluorescent Probe for Human Complement C3a Receptor.

    Science.gov (United States)

    Dantas de Araujo, Aline; Wu, Chongyang; Wu, Kai-Chen; Reid, Robert C; Durek, Thomas; Lim, Junxian; Fairlie, David P

    2017-06-21

    Measuring ligand affinity for a G protein-coupled receptor is often a crucial step in drug discovery. It has been traditionally determined by binding putative new ligands in competition with native ligand labeled with a radioisotope of finite lifetime. Competing instead with a lanthanide-based fluorescent ligand is more attractive due to greater longevity, stability, and safety. Here, we have chemically synthesized the 77 residue human C3a protein and conjugated its N-terminus to europium diethylenetriaminepentaacetate to produce a novel fluorescent protein (Eu-DTPA-hC3a). Time-resolved fluorescence analysis has demonstrated that Eu-DTPA-hC3a binds selectively to its cognate G protein-coupled receptor C3aR with full agonist activity and similar potency and selectivity as native C3a in inducing calcium mobilization and phosphorylation of extracellular signal-regulated kinases in HEK293 cells that stably expressed C3aR. Time-resolved fluorescence analysis for saturation and competitive binding gave a dissociation constant (Kd) of 8.7 ± 1.4 nM for Eu-DTPA-hC3a and binding affinities for hC3a (pKi of 8.6 ± 0.2 and Ki of 2.5 nM) and C3aR ligands TR16 (pKi of 6.8 ± 0.1 and Ki of 138 nM), BR103 (pKi of 6.7 ± 0.1 and Ki of 185 nM), BR111 (pKi of 6.3 ± 0.2 and Ki of 544 nM) and SB290157 (pKi of 6.3 ± 0.1 and Ki of 517 nM) via displacement of Eu-DTPA-hC3a from hC3aR. The macromolecular conjugate Eu-DTPA-hC3a is a novel nonradioactive probe suitable for studying ligand-C3aR interactions with potential value in accelerating drug development for human C3aR in physiology and disease.

  10. The Level of Europium-154 Contaminating Samarium-153-EDTMP Activates the Radiation Alarm System at the US Homeland Security Checkpoints.

    Science.gov (United States)

    Najeeb Al Hallak, Mohammed; McCurdy, Matt; Zouain, Nicolas; Hayes, Justin

    2009-08-28

    (153)Sm-EDTMP is a radiopharmaceutical composed of EDTMP (ethylenediamine-tetramethylenephosphonate) and Samarium-153 [1]. (153)Sm-EDTMP has an affinity for skeletal tissue and concentrates in areas with increased bone turnover; thus, it is successfully used in relieving pain related to diffuse bone metastases [1]. The manufacturing process of (153)Sm-EDTMP leads to contamination with (154)Eu (Europium-154) [2]. A previous study only alluded to the retention of (154)Eu in the bones after receiving treatment with (153)Sm-EDTMP [2]. Activation of the alarm at security checkpoints after (153)Sm-EDTMP therapy has not been previously reported. Two out of 15 patients who received (153)Sm-EDTMP at Roger Maris Cancer Center (Fargo, N. Dak., USA) activated the radiation activity sensors while passing through checkpoints; one at a US airport and the other while crossing the American-Canadian border. We assume that the (154)Eu which remained in the patients' bones activated the sensors. METHODS: In order to investigate this hypothesis, we obtained the consent from 3 of our 15 patients who received (153)Sm-EDTMP within the previous 4 months to 2 years, including the patient who had activated the radiation alarm at the airport. The patients were scanned with a handheld detector and a gamma camera for energies from 511 keV to 1.3 MeV. RESULTS: All three patients exhibited identical spectral images, and further analysis showed that the observed spectra are the result of (154)Eu emissions. CONCLUSION: Depending on the detection thresholds and windows used by local and federal authorities, the remaining activity of (154)Eu retained in patients who received (153)Sm-EDTMP could be sufficient enough to increase the count rates above background levels and activate the sensors. At Roger Maris Cancer Center, patients are now informed of the potential consequences of (153)Sm-EDTMP therapy prior to initiating treatment. In addition, patients treated with (153)Sm-EDTMP at Roger Maris Cancer

  11. 1.56 Micron Spectropolarimetry of Umbral Dots and Their Evolution Associated with a Major Flare

    Science.gov (United States)

    Deng, Na; Liu, Chang; Xu, Yan; Ahn, Kwangsu; Jing, Ju; Cao, Wenda; Wang, Haimin

    2017-08-01

    We present unprecedented high-resolution and high magnetic sensitivity spectropolarimetric characterization of umbral dots (UDs), the prevailing fine scale brightness structure manifesting magneto-convection inside sunspot umbrae where the magnetic fields are strongest and nearly vertical. This is made available by recent development of the Near InfraRed Imaging Spectropolarimeter (NIRIS) using the 1.56 micron FeI line at the 1.6 meter New Solar Telescope of Big Bear Solar Observatory. Vector magnetograms are obtained after Milne-Eddington Stokes inversions, 180-degree azimuthal ambiguity resolution, and correction of projection effects. A βγδ spot in NOAA AR 12371 was observed for six hours on June 22, 2015 with a cadence of 87 s, which covered an M6.6 flare. The overall umbra is separated into several smaller umbrae by light bridges. The umbrae are close to the flaring polarity inversion line and show an average inclination of about 17° and field strength of about 2100 Gauss. The UDs are resolvable in NIRIS vector magnetograms, especially for peripheral UDs. The measured field strength is about 3% lower in UDs comparing to umbral cores (UCs) where the continuum intensity is below the threshold of UDs. The field is more inclined in UDs by 5% ( ≈ 1°) than that in UCs. One of the umbrae showed rapid evolution associated with the flare. Its overall intensity and the number of UDs decrease by at least 7% within two hours after being swept by the flare ribbon. NIRIS vector magnetograms indicate that the average field strength of that umbra has a rapid stepwise increase for about 100 Gauss while the inclination almost has no change. The decreases of the umbral brightness and the number of UDs are thus attributed to the increase of the field strength. The results suggest that the field strength plays the most important role in constraining convective heat transport in umbra.

  12. Percutaneous image-guided splenic biopsy in the oncology patient: an audit of 156 consecutive cases.

    Science.gov (United States)

    Tam, Alda; Krishnamurthy, Savitri; Pillsbury, Edmund P; Ensor, Joe E; Gupta, Sanjay; Murthy, Ravi; Ahrar, Kamran; Wallace, Michael J; Hicks, Marshall E; Madoff, David C

    2008-01-01

    To assess the safety and diagnostic accuracy of percutaneous image-guided splenic biopsy in patients known to have or suspected of having malignancy. Data from all image-guided splenic biopsies performed at a single institution from January 1992 to March 2007 were retrospectively reviewed. One hundred fifty-six splenic biopsies were performed in 147 patients (78 male and 69 female patients; mean age, 54.9 years; age range, 13-81 years). The most common indications for biopsy were suspected recurrent lymphoma (n = 101, 64.7%), suspected metastatic disease (n = 39, 25%), and unknown diagnosis (n = 16, 10.3%). All biopsies were performed with computed tomographic (n = 86), ultrasonographic (n = 68), or fluoroscopic (n = 2) guidance. Most biopsies (91%) were performed with 22-gauge needles, with a mean of 2.8 passes. The mean lesion size was 3.2 cm (range, 0.8-13 cm). Final diagnosis was confirmed with splenectomy (n = 39), histopathologic correlation with concurrent biopsy or surgical specimen (n = 52), or clinical or imaging follow-up ranging from 2 weeks to 14 years (n = 44). Complications were recorded. Sufficient tissue for pathologic analysis was obtained in 144 of the 156 biopsies (diagnostic yield, 92.3%). The overall sensitivity, specificity, and diagnostic accuracy were 83.4%, 87.8%, and 84.7%, respectively. Complications occurred in 26 biopsies (16.7%), with a 1.9% (n = 3) major complication rate and a 14.7% (n = 23) minor complication rate. Splenectomy was necessary in two patients. Splenic biopsy in the evaluation of new or recurrent neoplasm is a minimally invasive procedure with low complication rates and a high diagnostic yield.

  13. Neutron cross section evaluations of europium isotopes in 1 keV - 30 MeV energy range. Format - validation - comparison; Evaluation de sections efficaces pour des neutrons incidents sur des isotopes d'europium aux energies 1 keV - 30 MeV. Format - validation - comparaison

    Energy Technology Data Exchange (ETDEWEB)

    Dossantos-Uzarralde, P.; Le Luel, C.; Bauge, E. [CEA Bruyeres le Chatel, 91 (France). Dept. de Physique Theorique et Appliquee

    2004-07-01

    This paper presents neutron cross section evaluations of Europium isotopes. The cross sections are evaluated in 1 keV - 30 MeV energy range for the isotopes {sup 146}Eu, {sup 147}Eu, {sup 148}Eu, {sup 149}Eu, {sup 150}Eu, {sup 151}Eu, {sup 152}Eu, {sup 153}Eu, {sup 154}Eu in their ground state. This evaluation includes cross section productions of the long life isomeric states. Special attention is put on the options used for the description of the files written in ENDF-6 format. The final issue is a proposal of a new breed of ENDF-6 formatted neutron activation file. (authors)

  14. Developmental Functions of miR156-Regulated SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL Genes in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Mingli Xu

    2016-08-01

    Full Text Available Correct developmental timing is essential for plant fitness and reproductive success. Two important transitions in shoot development-the juvenile-to-adult vegetative transition and the vegetative-to-reproductive transition-are mediated by a group of genes targeted by miR156, SQUAMOSA PROMOTER BINDING PROTEIN (SBP genes. To determine the developmental functions of these genes in Arabidopsis thaliana, we characterized their expression patterns, and their gain-of-function and loss-of-function phenotypes. Our results reveal that SBP-LIKE (SPL genes in Arabidopsis can be divided into three functionally distinct groups: 1 SPL2, SPL9, SPL10, SPL11, SPL13 and SPL15 contribute to both the juvenile-to-adult vegetative transition and the vegetative-to-reproductive transition, with SPL9, SP13 and SPL15 being more important for these processes than SPL2, SPL10 and SPL11; 2 SPL3, SPL4 and SPL5 do not play a major role in vegetative phase change or floral induction, but promote the floral meristem identity transition; 3 SPL6 does not have a major function in shoot morphogenesis, but may be important for certain physiological processes. We also found that miR156-regulated SPL genes repress adventitious root development, providing an explanation for the observation that the capacity for adventitious root production declines as the shoot ages. miR156 is expressed at very high levels in young seedlings, and declines in abundance as the shoot develops. It completely blocks the expression of its SPL targets in the first two leaves of the rosette, and represses these genes to different degrees at later stages of development, primarily by promoting their translational repression. These results provide a framework for future studies of this multifunctional family of transcription factors, and offer new insights into the role of miR156 in Arabidopsis development.

  15. CM156, a high affinity sigma ligand, attenuates the stimulant and neurotoxic effects of methamphetamine in mice.

    Science.gov (United States)

    Kaushal, Nidhi; Seminerio, Michael J; Shaikh, Jamaluddin; Medina, Mark A; Mesangeau, Christophe; Wilson, Lisa L; McCurdy, Christopher R; Matsumoto, Rae R

    2011-01-01

    Methamphetamine (METH) is a highly addictive psychostimulant drug of abuse. Low and high dose administration of METH leads to locomotor stimulation, and dopaminergic and serotonergic neurotoxicity, respectively. The behavioral stimulant and neurotoxic effects of METH can contribute to addiction and other neuropsychiatric disorders, thus necessitating the identification of potential pharmacotherapeutics against these effects produced by METH. METH binds to σ receptors at physiologically relevant concentrations. Also, σ receptors are present on and can modulate dopaminergic and serotonergic neurons. Therefore, σ receptors provide a viable target for the development of pharmacotherapeutics against the adverse effects of METH. In the present study, CM156, a σ receptor ligand with high affinity and selectivity for σ receptors over 80 other non-σ binding sites, was evaluated against METH-induced stimulant, hyperthermic, and neurotoxic effects. Pretreatment of male, Swiss Webster mice with CM156 dose dependently attenuated the locomotor stimulation, hyperthermia, striatal dopamine and serotonin depletions, and striatal dopamine and serotonin transporter reductions produced by METH, without significant effects of CM156 on its own. These results demonstrate the ability of a highly selective σ ligand to mitigate the effects of METH. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Complexation of lactate with neodymium(III) and europium(III) at variable temperatures: studies by potentiometry, microcalorimetry, optical absorption, and luminescence spectroscopy.

    Science.gov (United States)

    Tian, Guoxin; Martin, Leigh R; Rao, Linfeng

    2010-11-15

    The complexation of neodymium(III) and europium(III) with lactate was studied at variable temperatures by potentiometry, absorption spectrophotometry, luminescence spectroscopy, and microcalorimetry. The stability constants of three successive lactate complexes (ML(2+), ML(2)(+), and ML(3)(aq), where M stands for Nd and Eu and L stands for lactate) at 10, 25, 40, 55, and 70 °C were determined. The enthalpies of complexation at 25 °C were determined by microcalorimetry. Thermodynamic data show that the complexation of trivalent lanthanides (Nd(3+) and Eu(3+)) with lactate is exothermic and the complexation becomes weaker at higher temperatures. Results from optical absorption and luminescence spectroscopy suggest that the complexes are inner-sphere chelate complexes in which the protonated α-hydroxyl group of lactate participates in the complexation.

  17. Selective separation of americium from europium using 2,9-bis(triazine)-1,10-phenanthrolines in ionic liquids: a new twist on an old story.

    Science.gov (United States)

    Williams, Neil J; Dehaudt, Jérémy; Bryantsev, Vyacheslav S; Luo, Huimin; Abney, Carter W; Dai, Sheng

    2017-02-28

    Bis-triazine phenanthrolines have shown great promise for f-block metal separations, attributable to their highly preorganized structure, nitrogen donors, and more enhanced covalent bonding with actinides over lanthanides. However, their limited solubility in traditional solvents remains a technological bottleneck. Herein we report our recent work using a simple 2,9-bis(triazine)-1,10-phenanthroline (Me-BTPhen) dissolved in an ionic liquid (IL), demonstrating the efficacy of IL extraction systems for the selective separation of americium from europium, achieving separation factors in excess of 7500 and selectively removing up to 99% of the americium. Characterization of the coordination environment was performed using a combination of X-ray absorption fine structure spectroscopy (XAFS) and density functional theory (DFT) calculations.

  18. Experimental and Theoretical Studies on the Structure and Photoluminescent Properties of New Mononuclear and Homodinuclear Europium(III β-Diketonate Complexes

    Directory of Open Access Journals (Sweden)

    João P. Martins

    2015-01-01

    Full Text Available Two novel europium(III complexes, a monomer and a homodimer, with 1-(4-chlorophenyl-4,4,4-trifluoro-1,3-butanedione (Hcbtfa and 5-chloro-1,10-phenanthroline (cphen ligands, formulated as [Eu(cbtfa3(cphen] and [Eu2(cbtfa4(cphen2(CH3O2], have been synthesized. Their structures have been elucidated by X-ray diffraction and their absorption and emission properties have been studied in the solid state. The experimental data has then been used to test the recently released LUMPAC software, a promising tool which can facilitate the design of more efficient lanthanide light-conversion molecular devices by combining ground state geometry, excited state energy, and luminescent properties calculations.

  19. Optical Temperature Probe Based on the Fluorescence Decay Time of Tris-(dibenzoylmethane mono (5-amino-1,10-phenanthroline-europium(III

    Directory of Open Access Journals (Sweden)

    Hung T. LAM

    2010-08-01

    Full Text Available The measurement of temperature is essential in defining the physical and chemical properties of any system. This is particularly true in dynamic systems where the temperature may fluctuate during the process. In this paper we investigated the potential of tris-(dibenzoylmethane mono (5-amino-1, 10-phenanthroline-europium(III ( Eu[tdap] as an optical temperature probe. The principle of the measurement is based on the temperature dependence of the fluorescence decay time of Eu(tdap embedded in polystyrene. Within the investigated temperature range between 3 and 70°C a linear correlation between temperature and decay time was found. The probe is accurate and repeatable and there is no cross-sensitivity to pH changes. Continuous measurement for more than 2.5 hours at which the temperature is switched between two different temperatures shows no signal drift. The relative standard deviation is less than 0.65 percent.

  20. Crystal structure and luminescence of a europium coordination polymer {[Eu( m-MOBA) 3·2H 2O]1/2(4,4'-bpy)} ∞

    Science.gov (United States)

    Li, X.; Zheng, X.; Jin, L.; Lu, S.; Qin, W.

    2000-02-01

    The structure of the complex [Eu( m-MOBA) 3·2H 2O]1/2(4,4'-bpy) ( m-MOBA: m-methoxybenzoate, 4,4'-bpy: 4,4'-bipyridine) was determined by single crystal X-ray diffraction. The bonding around each europium consists of two oxygen atoms of the chelated carboxyl group, two oxygen atoms of two water molecules and four oxygen atoms of the bidentate bridging carboxylate groups, forming an infinite polymeric chain structure. The luminescence behaviour of Eu 3+ in {[Eu( m-MOBA) 3·2H 2O]1/2(4,4'-bpy)} ∞ was observed at 77 K. The emission spectra of 5D 1→ 7F J ( J=1-3) and 5D 0→ 7F J ( J=0-4) transitions were recorded. The complex displays intense luminescence which may be related to the m-MOBA ligand and the polymeric coordination.

  1. Synthesis and luminescence properties of two novel europium (III) perchlorate complexes with bis(benzylsulfinyl)methane and 1,10-phenanthroline

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wen-Xian, E-mail: nmglwx@163.com [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China); Guo, Feng [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China); Zheng, Yu-Shan [Inner Mongolia Autonomous Region Product Quality Inspection Institute, Hohhot 010010 (China); Cao, Xiao-Fang; Feng, Shu-Yan; Bai, Juan; Xin, Xiao-Dong [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China)

    2014-09-15

    Two novel binary and ternary Europium (III) perchlorate complexes were synthesized. The binary complex was prepared with bis(benzylsulfinyl)methane as ligand, and the ternary complex was with bis(benzylsulfinyl)methane as first ligand and 1,10-Phenanthroline as second ligand. They were characterized by element analysis, molar conductivity, coordination titration analysis, IR, TG-DSC, {sup 1}HNMR and UV spectra. The results indicated that the composition of binary and ternary complexes was EuL{sub 2.5}·(ClO{sub 4}){sub 3}·3H{sub 2}O and Eu{sub 2}L{sub 4}·phen·(ClO{sub 4}){sub 6}·12H{sub 2}O (L=C{sub 6}H{sub 5}CH{sub 2}SOCH{sub 2}SOCH{sub 2}C{sub 6}H{sub 5}), respectively. The fluorescent spectra illustrated that the complexes displayed characteristic Europium (III) ion fluorescence in solid state, indicating the ligands favored energy transfer to the excitation state energy level of it. The strongest characteristic fluorescence emission intensity of the ternary system was 1.87 times as strong as that of the binary system. The fluorescent quantum yields of the Eu (III) ternary and binary complexes were also calculated. Additionally, the phosphorescence spectra and the luminescence mechanisms of the complexes were studied and explained. - Highlights: • Two rare earth complexes are new. And they are stabilized. • The intensities of the two rare earth complexes were all stronger and the lifetimes were longer. • The introduction of the second organic ligand1,10-Phenanthroline enhanced the fluorescence intensity. • The fluorescent quantum yields of two complexes being calculated are both very high.

  2. High miR156 Expression Is Required for Auxin-Induced Adventitious Root Formation via MxSPL26 Independent of PINs and ARFs in Malus xiaojinensis

    Directory of Open Access Journals (Sweden)

    Xiaozhao Xu

    2017-06-01

    Full Text Available Adventitious root formation is essential for the vegetative propagation of perennial woody plants. During the juvenile-to-adult phase change mediated by the microRNA156 (miR156, the adventitious rooting ability decreases dramatically in many species, including apple rootstocks. However, the mechanism underlying how miR156 affects adventitious root formation is unclear. In the present study, we showed that in the presence of the synthetic auxin indole-3-butyric acid (IBA, semi-lignified leafy cuttings from juvenile phase (Mx-J and rejuvenated (Mx-R Malus xiaojinensis trees exhibited significantly higher expression of miR156, PIN-FORMED1 (PIN1, PIN10, and rootless concerning crown and seminal roots-like (RTCS-like genes, thus resulting in higher adventitious rooting ability than those from adult phase (Mx-A trees. However, the expression of SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE26 (SPL26 and some auxin response factor (ARF gene family members were substantially higher in Mx-A than in Mx-R cuttings. The expression of NbRTCS-like but not NbPINs and NbARFs varied with miR156 expression in tobacco (Nicotiana benthamiana plants transformed with 35S:MdMIR156a6 or 35S:MIM156 constructs. Overexpressing the miR156-resistant MxrSPL genes in tobacco confirmed the involvement of MxSPL20, MxSPL21&22, and MxSPL26 in adventitious root formation. Together, high expression of miR156 was necessary for auxin-induced adventitious root formation via MxSPL26, but independent of MxPINs and MxARFs expression in M. xiaojinensis leafy cuttings.

  3. Luminescent europium and terbium complexes of dipyridoquinoxaline and dipyridophenazine ligands as photosensitizing antennae: structures and biological perspectives.

    Science.gov (United States)

    Dasari, Srikanth; Patra, Ashis K

    2015-12-14

    The europium(III) and terbium(III) complexes, namely [Eu(dpq)(DMF)2(NO3)3] (1), [Eu(dppz)2(NO3)3] (2), [Tb(dpq)(DMF)2Cl3] (3), and [Tb(dppz)(DMF)2Cl3] (4), where dipyrido[3,2-d:2',3'-f]quinoxaline (dpq in 1 and 3), dipyrido[3,2-a:2',3'-c]phenazine (dppz in 2 and 4) and N,N'-dimethylformamide (DMF) have been isolated, characterized from their physicochemical data, luminescence studies and their interaction with DNA, serum albumin protein and photo-induced DNA cleavage activity are studied. The X-ray crystal structures of complexes 1-4 show discrete mononuclear Ln(3+)-based structures. The Eu(3+) in [Eu(dpq)(DMF)2(NO3)3] (1) and [Eu(dppz)2(NO3)3] (2) as [Eu(dppz)2(NO3)3]·dppz (2a) adopts a ten-coordinated bicapped dodecahedron structure with a bidentate N,N-donor dpq ligand, two DMF and three NO3(-) anions in 1 and two bidentate N,N-donor dppz ligands and three NO3(-) anions in 2. Complexes 3 and 4 show a seven-coordinated mono-capped octahedron structure where Tb(3+) contains bidentate dpq/dppz ligands, two DMF and three Cl(-) anions. The complexes are highly luminescent in nature indicating efficient photo-excited energy transfer from the dpq/dppz antenna to Ln(3+) to generate long-lived emissive excited states for characteristic f → f transitions. The time-resolved luminescence spectra of complexes 1-4 show typical narrow emission bands attributed to the (5)D0 → (7)F(J) and (5)D4 → (7)F(J) f-f transitions of Eu(3+) and Tb(3+) ions respectively. The number of inner-sphere water molecules (q) was determined from luminescence lifetime measurements in H2O and D2O confirming ligand-exchange reactions with water in solution. The complexes display significant binding propensity to the CT-DNA giving binding constant values in the range of 1.0 × 10(4)-6.1 × 10(4) M(-1) in the order 2, 4 (dppz) > 1, 3 (dpq). DNA binding data suggest DNA groove binding with the partial intercalation nature of the complexes. All the complexes also show binding propensity (K(BSA)

  4. Application of a room temperature ionic liquid for nuclear spent fuel reprocessing: speciation of trivalent europium and solvatation effects; Application d'un liquide ionique basse temperature pour les procedes de separation: speciation de l'europium trivalent et effets solvatation

    Energy Technology Data Exchange (ETDEWEB)

    Moutiers, G.; Mekki, S. [CEA Saclay, Dept. de Physico-Chimie, Service de Chimie Physique, 91 - Gif sur Yvette (France); Billard, I. [IN2P3/CNRS, 69 - Villeurbanne (France)

    2007-07-01

    One of the solutions proposed for the optimization of the long term storage and conditioning of spent nuclear fuel is to separate actinide and lanthanide both from each other and from other less radioactive metallic species. The industrial proposed processes, based on liquid liquid extraction steps, involve solvents with non negligible vapour pressure and may generate contaminated liquid wastes that will have to be reprocessed. During the last decade, some room-temperature ionic liquids have been studied and integrated into industrial processes. The interest on this class of solvent came out from their 'green' properties (non volatile, non flammable, recyclable, etc...), but also from the variability of their physico-chemical properties (stability, hydrophobicity, viscosity) as a function of the RTIL chemical composition. Indeed, it has been shown that classical chemical industrial processes could be transferred into those media, even more improved, while a certain number of difficulties arising from using traditional solvent can be avoided. In this respect, it could be promising to investigate the ability to use room temperature ionic liquid into the spent nuclear fuel reprocessing field. The aim of this this study is to test the ability of the specific ionic liquid bumimTf{sub 2}N to allow trivalent europium extraction. The choice of this metal is based on the chemical analogy with trivalent minor actinides Curium and Americium which are contributing the greatest part of the long-lived high level radioactive wastes. Handling these elements needs to be very cautious for the safety and radioprotection aspect. Moreover, europium is a very sensitive luminescent probe to its environment even at the microscopic scale. The report is structured with four parts. In a first chapter, we present the main physico-chemical properties of an imidazolium-based ionic liquid family, and then we choose the ionic liquid bumimTf{sub 2}N for the whole thesis and start with

  5. International distribution and age estimation of the Portuguese BRCA2 c.156_157insAlu founder mutation

    DEFF Research Database (Denmark)

    Peixoto, Ana; Santos, Catarina; Pinheiro, Manuela

    2011-01-01

    The c.156_157insAlu BRCA2 mutation has so far only been reported in hereditary breast/ovarian cancer (HBOC) families of Portuguese origin. Since this mutation is not detectable using the commonly used screening methodologies and must be specifically sought, we screened for this rearrangement...... individuals requesting predictive testing living in France and in the USA, all being Portuguese immigrants. After performing an extensive haplotype study in carrier families, we estimate that this founder mutation occurred 558 +/- 215 years ago. We further demonstrate significant quantitative differences...... HBOC families from Portugal or with Portuguese ancestry are specifically tested for this rearrangement....

  6. International distribution and age estimation of the Portuguese BRCA2 c.156_157insAlu founder mutation

    DEFF Research Database (Denmark)

    Peixoto, Ana; Santos, Catarina; Pinheiro, Manuela

    2011-01-01

    The c.156_157insAlu BRCA2 mutation has so far only been reported in hereditary breast/ovarian cancer (HBOC) families of Portuguese origin. Since this mutation is not detectable using the commonly used screening methodologies and must be specifically sought, we screened for this rearrangement...... individuals requesting predictive testing living in France and in the USA, all being Portuguese immigrants. After performing an extensive haplotype study in carrier families, we estimate that this founder mutation occurred 558 ± 215 years ago. We further demonstrate significant quantitative differences...... HBOC families from Portugal or with Portuguese ancestry are specifically tested for this rearrangement....

  7. Both the dimerization and immunochemical properties of E-cadherin EC1 domain depend on Trp(156) residue

    DEFF Research Database (Denmark)

    Laur, Oscar Y; Klingelhöfer, Jörg; Troyanovsky, Regina B

    2002-01-01

    Using site-directed mutagenesis, we show in this paper that the adhesive interface detected in cadherin crystals is unlikely to mediate adhesive interaction between myc- and flag-tagged E-cadherin molecules in human A-431 cells. We also found that a critical residue within this interface, His(233...... on the same intramolecular interaction between Trp(156) and its hydrophobic pocket. Our data suggest that this interaction may have an important regulatory function in controlling the surface topology of the NH(2)-terminal domain of E-cadherin....

  8. Nuclear structure effects of the nuclei {sup 152,154,156}Dy at high excitation energy and large angular momentum

    Energy Technology Data Exchange (ETDEWEB)

    Martin, V. [Analisis Numerico, Facultad de Informatica, Universidad Politecnica de Madrid, E-28660 Madrid (Spain); Egido, J.L. [Departamento de Fisica Teorica C-XI, Universidad Autonoma de Madrid, E-28049 Madrid (Spain)

    1995-06-01

    Using the finite-temperature Hartree-Fock-Bogoliubov formalism we analyze the properties of the nuclei {sup 152,154,156}Dy at the quasicontinuum region from {ital I}=0{h_bar} to 70{h_bar} and excitation energy up to approximately 16 MeV. We discuss energy gaps, shapes, moments of inertia, and entropy among others. The role of shape fluctuations is studied in the frame of classical statistics and we find large effects on several observables. A very rich structure is found in terms of excitation energy and angular momentum.

  9. New metformin derivative HL156A prevents oral cancer progression by inhibiting the insulin-like growth factor/AKT/mammalian target of rapamycin pathways.

    Science.gov (United States)

    Lam, Thuy Giang; Jeong, Yun Soo; Kim, Soo-A; Ahn, Sang-Gun

    2017-12-29

    Metformin is a biguanide widely prescribed as an antidiabetic drug for type 2 diabetes mellitus patients. The purpose of the present study was to observe the effects of the new metformin derivative, HL156A, on human oral cancer cell and to investigate its possible mechanisms. It was observed that HL156A significantly decreased FaDu and YD-10B cell viability and colony formation in a dose-dependent way. HL156A also markedly reduced wound closure and migration of FaDu and YD-10B cells. We observed that HL156A decreased mitochondrial membrane potential and induced reactive oxygen species (ROS) levels and apoptotic cells with caspase-3 and -9 activation. HL156A inhibited the expression and activation of insulin-like growth factor (IGF)-1 and its downstream proteins, AKT, mammalian target of rapamycin (mTOR), and ERK1/2. In addition, HL156A activated AMP-activated protein kinase/nuclear factor kappa B (AMPK-NF-κB) signaling of FaDu and YD-10B cells. A xenograft mouse model further showed that HL156A suppressed AT84 mouse oral tumor growth, accompanied by down-regulated p-IGF-1, p-mTOR, proliferating cell nuclear antigen (PCNA) and promoted p-AMPK and TUNEL expression. These results suggest the potential value of the new metformin derivative HL156A as a candidate for a therapeutic modality for the treatment of oral cancer. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  10. Myxoma Virus Immunomodulatory Protein M156R is a Structural Mimic of Eukaryotic Translation Initiation Factor eIF2 alpha

    Energy Technology Data Exchange (ETDEWEB)

    Ramelot, Theresa A.; Cort, John R.; Yee, Adelinda; Liu, Furong; Goshe, Michael B.; Edwards, Aled M.; Smith, Richard D.; Arrowsmith, Cheryl H.; Dever, Thomas E.; Kennedy, Michael A.

    2002-10-04

    M156R, the product of the myxoma virus M156R open reading frame, is a protein of unknown function. However, several homologs of M156R from other viruses are immunomodulatory proteins that bind to interferon-induced protein kinase PKR and inhibit phosphorylation of the eukaryotic translation initiation factor eIF2a. In this study, we have determined the nuclear magnetic resonance (NMR) structure of M156R, the first structure of a myxoma virus protein. The fold consists of a five-stranded antiparallel b-barrel with two of the strands connected by a long loop and a short a-helix. The similarity between M156R and the predicted S1 motif structure of eIF2a suggests that the viral homologs are pseudosubstrate inhibitors of PKR that mimic eIF2a in order to compete for binding to PKR. A homology modeled structure of the well studied vaccinia virus K3L was generated based on alignment with M156R. Residues important for binding to PKR are conserved residues on the surface of the b-barrel and in the mobile loop, identifying the putative PKR recognition motif.

  11. Genome Shuffling and Gentamicin-Resistance to Improve ε-Poly-L-Lysine Productivity of Streptomyces albulus W-156.

    Science.gov (United States)

    Wang, Liang; Chen, Xusheng; Wu, Guangyao; Zeng, Xin; Ren, Xidong; Li, Shu; Tang, Lei; Mao, Zhonggui

    2016-12-01

    Genome shuffling has been a recently effective method for screening the desirable phenotypes of industrial strains. Here, we combined genome shuffling and gentamicin resistance to improve the production of ε-poly-L-lysine in Streptomyces albulus W-156. Five starting mutants with higher ε-poly-L-lysine (ε-PL) productivities were firstly obtained by atmospheric and room temperature plasma (ARTP) mutagenesis. After three rounds of genome shuffling with increasing concentration of gentamicin for selection, S. albulus AG3-28, was finally got with a production of 3.43 g/L in shaking flask. In a 5-L fermenter, AG3-28 exhibited a higher ε-PL productivity (56.5 g/L) than the initial strain W-156 (37.5 g/L). Key enzyme activities in primary and secondary metabolic pathways were analyzed, and the transcription levels of hrdD and pls were determined by quantitative real time-polymerase chain reaction (qRT-PCR). Increase of key enzyme activities and the upregulation of the gene transcriptional levels demonstrated that ε-PL synthetic pathway in AG3-28 was obviously strengthened, which might be responsible for the high productivity. Moreover, hyper-yield strain AG3-28 was found to produce a slightly lower ε-PL polymerization degree than the parent strain. Amplified fragment length polymorphism (AFLP) analysis reflects the genetic diversity among the derivates after genome shuffling.

  12. Small RNA Profiling of Two Important Cultivars of Banana and Overexpression of miRNA156 in Transgenic Banana Plants

    Science.gov (United States)

    Ganapathi, Thumballi R.

    2015-01-01

    Micro RNAs (miRNAs) are a class of non-coding, short RNAs having important roles in regulation of gene expression. Although plant miRNAs have been studied in detail in some model plants, less is known about these miRNAs in important fruit plants like banana. miRNAs have pivotal roles in plant growth and development, and in responses to diverse biotic and abiotic stress stimuli. Here, we have analyzed the small RNA expression profiles of two different economically significant banana cultivars by using high-throughput sequencing technology. We identified a total of 170 and 244 miRNAs in the two libraries respectively derived from cv. Grand Naine and cv. Rasthali leaves. In addition, several cultivar specific microRNAs along with their putative target transcripts were also detected in our studies. To validate our findings regarding the small RNA profiles, we also undertook overexpression of a common microRNA, MusamiRNA156 in transgenic banana plants. The transgenic plants overexpressing the stem-loop sequence derived from MusamiRNA156 gene were stunted in their growth together with peculiar changes in leaf anatomy. These results provide a foundation for further investigations into important physiological and metabolic pathways operational in banana in general and cultivar specific traits in particular. PMID:25962076

  13. Small RNA Profiling of Two Important Cultivars of Banana and Overexpression of miRNA156 in Transgenic Banana Plants.

    Directory of Open Access Journals (Sweden)

    Siddhesh B Ghag

    Full Text Available Micro RNAs (miRNAs are a class of non-coding, short RNAs having important roles in regulation of gene expression. Although plant miRNAs have been studied in detail in some model plants, less is known about these miRNAs in important fruit plants like banana. miRNAs have pivotal roles in plant growth and development, and in responses to diverse biotic and abiotic stress stimuli. Here, we have analyzed the small RNA expression profiles of two different economically significant banana cultivars by using high-throughput sequencing technology. We identified a total of 170 and 244 miRNAs in the two libraries respectively derived from cv. Grand Naine and cv. Rasthali leaves. In addition, several cultivar specific microRNAs along with their putative target transcripts were also detected in our studies. To validate our findings regarding the small RNA profiles, we also undertook overexpression of a common microRNA, MusamiRNA156 in transgenic banana plants. The transgenic plants overexpressing the stem-loop sequence derived from MusamiRNA156 gene were stunted in their growth together with peculiar changes in leaf anatomy. These results provide a foundation for further investigations into important physiological and metabolic pathways operational in banana in general and cultivar specific traits in particular.

  14. Small RNA Profiling of Two Important Cultivars of Banana and Overexpression of miRNA156 in Transgenic Banana Plants.

    Science.gov (United States)

    Ghag, Siddhesh B; Shekhawat, Upendra K S; Ganapathi, Thumballi R

    2015-01-01

    Micro RNAs (miRNAs) are a class of non-coding, short RNAs having important roles in regulation of gene expression. Although plant miRNAs have been studied in detail in some model plants, less is known about these miRNAs in important fruit plants like banana. miRNAs have pivotal roles in plant growth and development, and in responses to diverse biotic and abiotic stress stimuli. Here, we have analyzed the small RNA expression profiles of two different economically significant banana cultivars by using high-throughput sequencing technology. We identified a total of 170 and 244 miRNAs in the two libraries respectively derived from cv. Grand Naine and cv. Rasthali leaves. In addition, several cultivar specific microRNAs along with their putative target transcripts were also detected in our studies. To validate our findings regarding the small RNA profiles, we also undertook overexpression of a common microRNA, MusamiRNA156 in transgenic banana plants. The transgenic plants overexpressing the stem-loop sequence derived from MusamiRNA156 gene were stunted in their growth together with peculiar changes in leaf anatomy. These results provide a foundation for further investigations into important physiological and metabolic pathways operational in banana in general and cultivar specific traits in particular.

  15. Regulation of OsSPL14 by OsmiR156 defines ideal plant architecture in rice.

    Science.gov (United States)

    Jiao, Yongqing; Wang, Yonghong; Xue, Dawei; Wang, Jing; Yan, Meixian; Liu, Guifu; Dong, Guojun; Zeng, Dali; Lu, Zefu; Zhu, Xudong; Qian, Qian; Li, Jiayang

    2010-06-01

    Increasing crop yield is a major challenge for modern agriculture. The development of new plant types, which is known as ideal plant architecture (IPA), has been proposed as a means to enhance rice yield potential over that of existing high-yield varieties. Here, we report the cloning and characterization of a semidominant quantitative trait locus, IPA1 (Ideal Plant Architecture 1), which profoundly changes rice plant architecture and substantially enhances rice grain yield. The IPA1 quantitative trait locus encodes OsSPL14 (SOUAMOSA PROMOTER BINDING PROTEIN-LIKE 14) and is regulated by microRNA (miRNA) OsmiR156 in vivo. We demonstrate that a point mutation in OsSPL14 perturbs OsmiR156-directed regulation of OsSPL14, generating an 'ideal' rice plant with a reduced tiller number, increased lodging resistance and enhanced grain yield. Our study suggests that OsSPL14 may help improve rice grain yield by facilitating the breeding of new elite rice varieties.

  16. Synthesis, characterization and luminescence of europium perchlorate with MABA-Si complex and coating structure SiO2@Eu(MABA-Si) luminescence nanoparticles.

    Science.gov (United States)

    Fu, Zhi-Fang; Li, Wen-Xian; Bai, Juan; Bao, Jin-Rong; Cao, Xiao-Fang; Zheng, Yu-Shan

    2017-05-01

    This article reports a novel category of coating structure SiO 2 @Eu(MABA-Si) luminescence nanoparticles (NPs) consisting of a unique organic shell, composed of perchlorate europium(III) complex, and an inorganic core, composed of silica. The binary complex Eu(MABA-Si) 3 ·(ClO 4 ) 3 ·5H 2 O was synthesized using HOOCC 6 H 4 N(CONH(CH 2 ) 3 Si(OCH 2 CH 3 ) 3 ) 2 (MABA-Si) and was used as a ligand. Furthermore, the as-prepared silica NPs were successfully coated with the -Si(OCH 2 CH 3 ) 3 group of MABA-Si to form Si-O-Si chemical bonds by means of the hydrolyzation of MABA-Si. The binary complexes were characterized by elemental analysis, molar conductivity and coordination titration analysis. The results indicated that the composition of the binary complex was Eu(MABA-Si) 3 ·(ClO 4 ) 3 ·5H 2 O. Coating structure SiO 2 @Eu(MABA-Si) NPs were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM) and infrared (IR) spectra. Based on the SEM and TEM measurements, the diameter of core-SiO 2 particles was ~400 and 600 nm, and the thickness of the cladding layer Eu(MABA-Si) was ~20 nm. In the binary complex Eu(MABA-Si) 3 ·(ClO 4 ) 3 ·5H 2 O, the fluorescence spectra illustrated that the energy of the ligand MABA-Si transferred to the energy level for the excitation state of europium(III) ion. Coating structure SiO 2 @Eu(MABA-Si) NPs exhibited intense red luminescence compared with the binary complex. The fluorescence lifetime and fluorescence quantum efficiency of the binary complex and of the coating structure NPs were also calculated. The way in which the size of core-SiO 2 spheres influences the luminescence was also studied. Moreover, the luminescent mechanisms of the complex were studied and explained. Copyright © 2016 John Wiley & Sons, Ltd.

  17. The structures of CyMe4-BTBP complexes of americium(iii) and europium(iii) in solvents used in solvent extraction, explaining their separation properties.

    Science.gov (United States)

    Ekberg, Christian; Löfström-Engdahl, Elin; Aneheim, Emma; Foreman, Mark R StJ; Geist, Andreas; Lundberg, Daniel; Denecke, Melissa; Persson, Ingmar

    2015-11-14

    Separation of trivalent actinoid (An(iii)) and lanthanoid (Ln(iii)) ions is extremely challenging due to their similar ionic radii and chemical properties. Poly-aromatic nitrogen compounds acting as tetradentate chelating ligands to the metal ions in the extraction, have the ability to sufficiently separate An(iii) from Ln(iii). One of these compounds, 6,6'-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-benzol[1,2,4]triazin-3-yl)[2,2]bipyridine, CyMe4-BTBP, has proven to be resistant towards acidic environments and strong radiation from radioactive decomposition. EXAFS studies of the dicomplexes of CyMe4-BTBP with americium(iii) and europium(iii) in nitrobenzene, cyclohexanone, 1-hexanol, 1-octanol and malonamide (DMDOHEMA) in 1-octanol have been carried out to get a deeper understanding of the parameters responsible for the separation. The predominating complexes independent of solvent used are [Am(CyMe4-BTBP)2(NO3)](2+) and [Eu(CyMe4-BTBP)2](3+), respectively, which are present as outer-sphere ion-pairs with nitrate ions in the studied solvents with low relative permittivity. The presence of a nitrate ion in the first coordination sphere of the americium(iii) complex compensates the charge density of the complex considerably in comparison when only outer-sphere ion-pairs are formed as for the [Eu(CyMe4-BTBP)2](3+) complex. The stability and solubility of a complex in a solvent with low relative permittivity increase with decreasing charge density. The [Am(CyMe4-BTBP)2(NO3)](2+) complex will therefore be increasingly soluble and stabilized over the [Eu(CyMe4-BTBP)2](3+) complex in solvents with decreasing relative permittivity of the solvent. The separation of americium(iii) from europium(iii) with CyMe4-BTBP as extraction agent will increase with decreasing relative permittivity of the solvent, and thereby also with decreasing solubility of CyMe4-BTBP. The choice of solvent is therefore a balance of a high separation factor and sufficient solubility of the CyMe4-BTBP

  18. Europium-decorated graphene quantum dots as a fluorescent probe for label-free, rapid and sensitive detection of Cu{sup 2+} and L-cysteine

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Liping [College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002 (China); Song, Xinhong; Chen, Yiying; Rong, Mingcong; Wang, Yiru [Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005 (China); Zhao, Li; Zhao, Tingting [Xiamen Huaxia College, Xiamen, 361024 (China); Chen, Xi, E-mail: xichen@xmu.edu.cn [Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005 (China); State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361005 (China)

    2015-09-03

    In this work, europium-decorated graphene quantum dots (Eu-GQDs) were prepared by treating three-dimensional Eu-decorated graphene (3D Eu-graphene) via a strong acid treatment. Various characterizations revealed that Eu atoms were successfully complexed with the oxygen functional groups on the surface of graphene quantum dots (GQDs) with the atomic ratio of 2.54%. Compared with Eu free GQDs, the introduction of Eu atoms enhanced the electron density and improved the surface chemical activities of Eu-GQDs. Therefore, the obtained Eu-GQDs were used as a novel “off-on” fluorescent probe for the label-free determination of Cu{sup 2+} and L-cysteine (L-Cys) with high sensitivity and selectivity. The fluorescence intensity of Eu-GQDs was quenched in the presence of Cu{sup 2+} owing to the coordination reaction between Cu{sup 2+} and carboxyl groups on the surface of the Eu-GQDs. The fluorescence intensity of Eu-GQDs recovered with the subsequent addition of L-Cys because of the strong affinity of Cu{sup 2+} to L-Cys via the Cu–S bond. The experimental results showed that the fluorescence variation of the proposed approach had a good linear relationship in the range of 0.1–10 μM for Cu{sup 2+} and 0.5–50 μM for L-Cys with corresponding detection limits of 0.056 μM for Cu{sup 2+} and 0.31 μM for L-Cys. The current approach also displayed a special response to Cu{sup 2+} and L-Cys over the other co-existing metal ions and amino acids, and the results obtained from buffer-diluted serum samples suggested its applicability in biological samples. - Highlights: • The europium-decorated graphene quantum dots (Eu-GQDs) have been successfully prepared. • Various characterizations results proved that Eu atoms were successfully introduced into graphene quantum dots. • The introduced Eu atoms changed the electron density and surface chemical activities of Eu-GQDs. • Eu-GQDs were used as an “off-on” fluorescent probe for Cu{sup 2+} and L-cysteine detection

  19. miR156a Mimic Represses the Epithelial-Mesenchymal Transition of Human Nasopharyngeal Cancer Cells by Targeting Junctional Adhesion Molecule A.

    Science.gov (United States)

    Tian, Yunhong; Cai, Longmei; Tian, Yunming; Tu, Yinuo; Qiu, Huizhi; Xie, Guofeng; Huang, Donglan; Zheng, Ronghui; Zhang, Weijun

    2016-01-01

    MicroRNAs (miRNAs) have been documented as having an important role in the development of cancer. Broccoli is very popular in large groups of the population and has anticancer properties. Junctional adhesion molecule A (JAMA) is preferentially concentrated at tight junctions and influences cell morphology and migration. Epithelial-mesenchymal transition (EMT) is a developmental program associated with cancer progression and metastasis. In this study we aimed to investigate the role of miRNAs from broccoli in human nasopharyngeal cancer (NPC). We demonstrated that a total of 84 conserved miRNAs and 184 putative novel miRNAs were found in broccoli by sequencing technology. Among these, miR156a was expressed the most. In addition, synthetic miR156a mimic inhibited the EMT of NPC cells in vitro. Furthermore, it was confirmed that JAMA was the target of miR156a mimic as validated by 3' UTR luciferase reporter assays and western blotting. Knockdown of JAMA was consistent with the effects of miR156a mimic on the EMT of NPC, and the up-regulation of JAMA could partially restore EMT repressed by miR156a mimic. In conclusion, these results indicate that the miR156a mimic inhibits the EMT of NPC cells by targeting the 3' UTR of JAMA. These miRNA profiles of broccoli provide a fundamental basis for further research. Moreover, the discovery of miR156a may have clinical implications for the treatment of patients with NPC.

  20. Myxoma virus M156 is a specific inhibitor of rabbit PKR but contains a loss-of-function mutation in Australian virus isolates.

    Science.gov (United States)

    Peng, Chen; Haller, Sherry L; Rahman, Masmudur M; McFadden, Grant; Rothenburg, Stefan

    2016-04-05

    Myxoma virus (MYXV) is a rabbit-specific poxvirus, which is highly virulent in European rabbits. The attenuation of MYXV and the increased resistance of rabbits following the release of MYXV in Australia is one of the best-documented examples of host-pathogen coevolution. To elucidate the molecular mechanisms that contribute to the restriction of MYXV infection to rabbits and MYXV attenuation in the field, we have studied the interaction of the MYXV protein M156 with the host antiviral protein kinase R (PKR). In yeast and cell-culture transfection assays, M156 only inhibited rabbit PKR but not PKR from other tested mammalian species. Infection assays with human HeLa PKR knock-down cells, which were stably transfected with human or rabbit PKR, revealed that only human but not rabbit PKR was able to restrict MYXV infection, whereas both PKRs were able to restrict replication of a vaccinia virus (VACV) strain that lacks the PKR inhibitors E3 and K3. Inactivation of M156R led to MYXV virus attenuation in rabbit cells, which was rescued by the ectopic expression of VACV E3 and K3. We further show that a mutation in the M156 encoding gene that was identified in more than 50% of MYXV field isolates from Australia resulted in an M156 variant that lost its ability to inhibit rabbit PKR and led to virus attenuation. The species-specific inhibition of rabbit PKR by M156 and the M156 loss-of-function in Australian MYXV field isolates might thus contribute to the species specificity of MYXV and to the attenuation in the field, respectively.

  1. miR156a Mimic Represses the Epithelial-Mesenchymal Transition of Human Nasopharyngeal Cancer Cells by Targeting Junctional Adhesion Molecule A.

    Directory of Open Access Journals (Sweden)

    Yunhong Tian

    Full Text Available MicroRNAs (miRNAs have been documented as having an important role in the development of cancer. Broccoli is very popular in large groups of the population and has anticancer properties. Junctional adhesion molecule A (JAMA is preferentially concentrated at tight junctions and influences cell morphology and migration. Epithelial-mesenchymal transition (EMT is a developmental program associated with cancer progression and metastasis. In this study we aimed to investigate the role of miRNAs from broccoli in human nasopharyngeal cancer (NPC. We demonstrated that a total of 84 conserved miRNAs and 184 putative novel miRNAs were found in broccoli by sequencing technology. Among these, miR156a was expressed the most. In addition, synthetic miR156a mimic inhibited the EMT of NPC cells in vitro. Furthermore, it was confirmed that JAMA was the target of miR156a mimic as validated by 3' UTR luciferase reporter assays and western blotting. Knockdown of JAMA was consistent with the effects of miR156a mimic on the EMT of NPC, and the up-regulation of JAMA could partially restore EMT repressed by miR156a mimic. In conclusion, these results indicate that the miR156a mimic inhibits the EMT of NPC cells by targeting the 3' UTR of JAMA. These miRNA profiles of broccoli provide a fundamental basis for further research. Moreover, the discovery of miR156a may have clinical implications for the treatment of patients with NPC.

  2. Test of the X(5) symmetry in {sup 156}Dy and {sup 178}Os by measurement of electromagnetic transition probabilities; Test der X(5)-Symmetrie in {sup 156}Dy und {sup 178}Os durch Messung elektromagnetischer Uebergangswahrscheinlichkeiten

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, O.

    2005-07-01

    This work reports on results from two Recoil-Distance-Doppler-Shift lifetime measurements of excited states in {sup 155}Dy and {sup 178}Os. The experiments were carried out at the GASP spektrometer of the Laboratori Nazional i di Legnaro in combination with the Cologne plunger apparatus. The main purpose of the performed experiments was to test the predictions of the X(5) critical point symmetry in these two nuclei. In {sup 156}Dy and {sup 178}Os 29 lifetimes of excited states were derived using the Differential-Decay-Curve method. In weaker reaction channels the nuclei {sup 155}Dy, {sup 157}Dy and {sup 177}Os were populated. In these nuclei 32 additional lifetimes were measured, most of them for the first time. In order to calculate absolute transition probabilities from the measured lifetimes of the first excited band in {sup 156}Dy, essential branching ratios were derived from the measured data with a very small systematic error (<5%). The most important results can be summarized as mentioned below: Lifetimes measured in the first excited band, confirm that this nucleus can be located close to the critical point X(5). With model calculations, special criteria of the X(5) model were found that can be used to identify other X(5)-like nuclei. Using these criterias a new region of X(5)-like nuclei could be suggested within the osmium isotopes in the A=180 mass region. The measured lifetimes in {sup 178}Os confirm the consistency of a X(5) description in these nuclei. A comparision with the well established X(5)-like nuclei in the N=90 isotones gives an agreement with the X(5) description of at least the same quality. (orig.)

  3. Synthesis, structural characterization and luminescent properties of a novel europium ternary complex Eu(2-A-4-CBA){sub 3}phen

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yongjie, E-mail: cyj200507@aliyun.com; Wu, Shengnan; Xing, Zhenfang; Cao, Shuang; Geng, Xiujuan; Yang, Ying; Xiao, Linjiu

    2015-11-15

    The preparation of a novel europium ternary complex with the formula of Eu(2-A-4-CBA){sub 3}phen (where, 2-A-4-CBA = 2-amino-4-chlorobenzoic acid, phen = 1,10-phenanthroline) under solvothermal condition is described. The composition and structure of the resulting complex were investigated by elemental analysis, Fourier transform infrared (FT-IR) spectroscopy. The complex is polycrystalline, and the morphology is clean and regular as revealed by scanning electron microscope (SEM). The luminescent and thermal properties of the complex were researched by fluorescence spectroscopy and thermogravimetric analysis, respectively. Of importance here is that, the room-temperature luminescence spectra of the complex show strong characteristic emission of the corresponding Eu{sup 3+}, which is attributed to the energy transfer from ligands to Eu{sup 3+} via an Antenna effect. It is also found that the complex exhibits pure red light and high color purity. In addition, the complex does not decompose until 300 °C, so it exhibits good thermal stability. - Highlights: • A novel Eu(III) complex was synthesized by solvothermal synthesis method. • The structure and properties of complex were studied. • The complex can emits pure red light and has a high color purity. • The complex does not decompose until 300 °C and it has a good thermal stability.

  4. Size- and dimensionality-dependent optical, magnetic and magneto-optical properties of binary europium-based nanocrystals: EuX (X = O, S, Se, Te).

    Science.gov (United States)

    Zhou, Xingzhi; Zhang, Kelvin H L; Xiong, Jie; Park, Ju-Hyun; Dickerson, James H; He, Weidong

    2016-05-13

    Europium chalcogenides (EuX, X = O, S, Se, Te), a class of prototypical Heisenberg magnetic semiconductors, exhibit intriguing properties in optics, magnetism, and magneto-optics at the nanoscale, and have broad application potential in optical/magnetic sensors, spintronics, optical isolators, etc. EuX nanocrystals (NCs) exhibit enhanced properties, such as high saturation magnetization, a strong magneto-optic effect (Faraday rotation), and high magneto resistance, which are all unanimously dependent on the NC's size, shape, and surface information. In this report, we give an overview of the fundamental properties of bulk EuX, and illustrate the quantum confinement effects on the optical, magnetic and magneto-optical properties of EuX nanostructures. We then focus on doping and self-assembly-two efficient methods that enhance magnetic properties by manipulating magnetic coupling in EuX nanostructures. In particular, we look towards future research on Eu(2+) NCs, which along with the overview provides an up-to-date platform for evaluating the fundamental properties and application potential of Eu-based semiconductors.

  5. Crystal structure and luminescence properties of the first hydride oxide chloride with divalent europium. LiEu{sub 2}HOCl{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, Daniel; Schleid, Thomas [Institute for Inorganic Chemistry, University of Stuttgart (Germany); Enseling, David; Juestel, Thomas [Department of Chemical Engineering, Muenster University of Applied Sciences, Steinfurt (Germany)

    2017-11-17

    The mixed-anionic hydride oxide chloride LiEu{sub 2}HOCl{sub 2} with divalent europium was synthesized by the reduction of Eu{sub 2}O{sub 3} with LiH in a LiCl flux at 750 C for 4 d in silica-jacketed niobium capsules. According to structure determination by single-crystal X-ray diffraction the yellow compound crystallizes in the orthorhombic space group Cmcm (a = 1492.30(11) pm, b = 570.12(4) pm, c = 1143.71(8) pm, Z = 8) with a crystal structure closely related to that one of the quaternary hydride oxide LiLa{sub 2}HO{sub 3} and the hydride nitride LiSr{sub 2}H{sub 2}N. On the other hand it can also be derived from the PbFCl-type structure of EuHCl showing astonishingly short Eu{sup 2+}..Eu{sup 2+} contacts of 326 and 329 pm. Both crystallographically different Eu{sup 2+} cations have nine anionic neighbors, while all other ions (Li{sup +}, H{sup -}, O{sup 2-} and Cl{sup -}) reside in six-membered coordination spheres. LiEu{sub 2}OCl{sub 2}H exhibits a bright yellow luminescence with an emission maximum at 581 nm upon excitation at 440 nm. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Highly sensitive and novel point-of-care system, aQcare Chlamydia TRF kit for detecting Chlamydia trachomatis by using europium (Eu) (III) chelated nanoparticles.

    Science.gov (United States)

    Ham, Ji Yeon; Jung, Jaean; Hwang, Byung-Gap; Kim, Won-Jung; Kim, Young-Seop; Kim, Eun-Ju; Cho, Mi-Yeon; Hwang, Mi-Sun; Won, Dong Il; Suh, Jang Soo

    2015-01-01

    The bacterium Chlamydia trachomatis is one of the leading causes of sexually transmitted diseases worldwide. Since no simple and effective tool exists to diagnose C. trachomatis infections, we evaluated a novel point-of-care (POC) test, aQcare Chlamydia TRF kit, which uses europium-chelated nanoparticles and a time-resolved fluorescence reader. The test performance was evaluated by comparing the results obtained using the novel POC testing kit with those obtained using a nucleic acid amplification test (NAAT), using 114 NAAT-positive and 327 NAAT-negative samples. The cut-off value of the novel test was 20.8 with a detection limit of 0.27 ng/mL. No interference or cross-reactivity was observed. Diagnostic accuracy showed an overall sensitivity of 93.0% (106/114), specificity of 96.3% (315/327), positive predictive value (PPV) of 89.8% (106/118), and negative predictive value (NPV) of 97.5% (315/323). The sensitivity of the novel test was much higher than that of currently available POC tests. Furthermore, the relative ease and short turnaround time (30 min) of this assay enables C. trachomatis-infected individuals to be treated without a diagnostic delay. This simple and novel test is a potential tool to screen a larger population, especially those in areas with limited resources.

  7. Fluorescence enhancement of europium (III) perchlorate by 1,10-phenanthroline on the 1-(naphthalen-2-yl)-2-(phenylsulthio)ethanone complex and luminescence mechanism.

    Science.gov (United States)

    Li, Wen-Xian; Xin, Xiao-Dong; Feng, Shu-Yan; Liu, Yu; Zhang, Jing; Ao, Bo-Yang; Li, Ying-Jie

    2014-11-01

    A novel ligand, 1-(naphthalen-2-yl)-2-(phenylsulthio)ethanone was synthesized using a new method and its two europium (Eu) (III) complexes were synthesized. The compounds were characterized by elemental analysis, coordination titration analysis, molar conductivity, infrared, thermo gravimetric analyzer-differential scanning calorimetry (TGA-DSC), (1)H NMR and UV spectra. The composition was suggested as EuL5 · (ClO4)3 · 2H2O and EuL4 · phen(ClO4)3 · 2H2O (L = C(10)H(7)COCH(2)SOC(6)H(5)). The fluorescence spectra showed that the Eu(III) displayed strong characteristic metal-centered fluorescence in the solid state. The ternary rare earth complex showed stronger fluorescence intensity than the binary rare earth complex in such material. The strongest characteristic fluorescence emission intensity of the ternary system was 1.49 times as strong as that of the binary system. The phosphorescence spectra were also discussed. Copyright © 2014 John Wiley & Sons, Ltd.

  8. Matrix-Assisted Ionization-Ion Mobility Spectrometry-Mass Spectrometry: Selective Analysis of a Europium-PEG Complex in a Crude Mixture.

    Science.gov (United States)

    Fischer, Joshua L; Lutomski, Corinne A; El-Baba, Tarick J; Siriwardena-Mahanama, Buddhima N; Weidner, Steffen M; Falkenhagen, Jana; Allen, Matthew J; Trimpin, Sarah

    2015-12-01

    The analytical utility of a new and simple to use ionization method, matrix-assisted ionization (MAI), coupled with ion mobility spectrometry (IMS) and mass spectrometry (MS) is used to characterize a 2-armed europium(III)-containing poly(ethylene glycol) (Eu-PEG) complex directly from a crude sample. MAI was used with the matrix 1,2-dicyanobenzene, which affords low chemical background relative to matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI). MAI provides high ion abundance of desired products in comparison to ESI and MALDI. Inductively coupled plasma-MS measurements were used to estimate a maximum of 10% of the crude sample by mass was the 2-arm Eu-PEG complex, supporting evidence of selective ionization of Eu-PEG complexes using the new MAI matrix, 1,2-dicyanobenzene. Multiply charged ions formed in MAI enhance the IMS gas-phase separation, especially relative to the singly charged ions observed with MALDI. Individual components are cleanly separated and readily identified, allowing characterization of the 2-arm Eu-PEG conjugate from a mixture of the 1-arm Eu-PEG complex and unreacted starting materials. Size-exclusion chromatography, liquid chromatography at critical conditions, MALDI-MS, ESI-MS, and ESI-IMS-MS had difficulties with this analysis, or failed. Graphical Abstract ᅟ.

  9. Synthesis, characterization and luminescent properties of europium complexes with 2,4,6-tris-(2-pyridyl)-s-triazine as highly efficient sensitizers.

    Science.gov (United States)

    Kang, Jie; Chen, Ying-Nan; Wang, Ai-Ling; Li, Hai-Yan; Qu, Yan-Rong; Zhang, Hai-Xia; Chu, Hai-Bin; Zhao, Yong-Liang

    2015-12-01

    Using 2,4,6-tris-(2-pyridyl)-s-triazine (TPTZ) as a neutral ligand, and p-hydroxybenzoic acid, terephthalic acid and nitrate as anion ligands, five novel europium complexes have been synthesized. These complexes were characterized using elemental analysis, rare earth coordination titrations, UV/vis absorption spectroscopy and infrared spectroscopy. Luminescence spectra, luminescence lifetime and quantum efficiency were investigated and the mechanism discussed in depth. The results show that the complexes have excellent emission intensities, long emission lifetimes and high quantum efficiencies. The superior luminescent properties of the complexes may be because the triplet energy level of the ligands matches well with the lowest excitation state energy level of Eu(3+). Moreover, changing the ratio of the ligands and metal ions leads to different luminescent properties. Among the complexes, Eu2(TPTZ)2(C8H4O4)(NO3)4(C2H5OH)·H2O shows the strongest luminescence intensity, longest emission lifetime and highest quantum efficiency. Copyright © 2015 John Wiley & Sons, Ltd.

  10. Photo-catalytic inactivation of an Enterococcus biofilm: the anti-microbial effect of sulphated and europium-doped titanium dioxide nanopowders.

    Science.gov (United States)

    Dworniczek, Ewa; Plesch, Gustav; Seniuk, Alicja; Adamski, Ryszard; Michal, Róbert; Čaplovičová, Mária

    2016-04-01

    The control and prevention of biofilm-related infections is an important public healthcare issue. Given the increasing antibiotic resistance among bacteria and fungi that cause serious infections in humans, promotion of new strategies combating microorganisms has been essential. One attractive approach to inactivate microorganisms is the use of semiconductor photo-catalysis, which has become the subject of extensive research. In this study, the bactericidal properties of four photo-catalysts, TiO₂, TiO₂-S, TiO₂-Eu and TiO₂-Eu-S, were investigated against established 24, 48, 72 and 96 h biofilms of Enterococcus The exposure of biofilms to the catalysts induced the production of superoxide radical anions. The best photo-catalytic inactivation was achieved with the TiO₂-Eu-S and TiO₂-S nanopowders and 24 h biofilms. Transmission electron microscopy images showed significant changes in the structure of the biofilm cells following photo-inactivation. The results suggest that doping with europium and modifying the surface with sulphate groups enhanced the bactericidal activity of the TiO₂ nanoparticles against enterococcal biofilms. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Reversible modulation in luminescence intensity of a single vesicle composed of diblock azo-copolymer and tris(dibenzoylmethanate)(phenanthroline)europium(III)

    Science.gov (United States)

    Yan, Qing; Su, Wei; Chen, Yilong; Luo, Yanhua; Zhang, Qijin

    2009-01-01

    Tris(dibenzoylmethanate)(phenanthroline)europium(III)[Eu(DBM) 3Phen]-doped amphiphilic vesicles were obtained by self-assembling of poly( N-isopropylacrylamide)- b-poly{6-[4-(4-methylphenyl-azo) phenoxy] hexylacrylate} (PNIPAM 83- b-PAzoM 20) in presence of Eu(DBM) 3Phen in the mixed solvent of THF/H 2O (50/50 vol.%). Their optical properties were studied by UV-vis and fluorescence spectroscopies. The UV-vis spectrum showed that the electronic transition bands of azobenzene and Eu(DBM) 3Phen were overlapped at about 365 nm and the main peak of fluorescence emission band appeared at 612 nm. So the vesicles showed obvious red luminescence. It was found that the fluorescence intensity of a single Eu(DBM) 3Phen-doped vesicle could be modulated by irradiation with UV and visible light due to the reversible trans- cis- trans photoisomerization reaction of azobenzene moiety. Possible energy allocation process for this property was discussed in details.

  12. Size- and dimensionality-dependent optical, magnetic and magneto-optical properties of binary europium-based nanocrystals: EuX (X = O, S, Se, Te)

    Science.gov (United States)

    Zhou, Xingzhi; Zhang, Kelvin HL; Xiong, Jie; Park, Ju-Hyun; Dickerson, James H.; He, Weidong

    2016-05-01

    Europium chalcogenides (EuX, X = O, S, Se, Te), a class of prototypical Heisenberg magnetic semiconductors, exhibit intriguing properties in optics, magnetism, and magneto-optics at the nanoscale, and have broad application potential in optical/magnetic sensors, spintronics, optical isolators, etc. EuX nanocrystals (NCs) exhibit enhanced properties, such as high saturation magnetization, a strong magneto-optic effect (Faraday rotation), and high magneto resistance, which are all unanimously dependent on the NC’s size, shape, and surface information. In this report, we give an overview of the fundamental properties of bulk EuX, and illustrate the quantum confinement effects on the optical, magnetic and magneto-optical properties of EuX nanostructures. We then focus on doping and self-assembly—two efficient methods that enhance magnetic properties by manipulating magnetic coupling in EuX nanostructures. In particular, we look towards future research on Eu2+ NCs, which along with the overview provides an up-to-date platform for evaluating the fundamental properties and application potential of Eu-based semiconductors.

  13. A novel near monochromatic red emissive europium(III) metal-organic framework based on 1,2,4,5-benzenetetracarboxylate: From synthesis to photoluminescence studies

    Science.gov (United States)

    Lahoud, Marcelo G.; Frem, Regina C. G.; Marques, Lippy F.; Arroyos, Guilherme; Brandão, Paula; Ferreira, Rute A. S.; Carlos, Luís D.

    2017-09-01

    This work presents the synthesis, solid state characterization (infrared spectroscopy, thermal analysis (TGA/DTA), powder and single crystal X-ray diffraction) and photoluminescence studies of a new europium metal-organic framework (MOF), [Eu2(Btec)1,5(H2O)]n (Btec4-=1,2,4,5-benzenetetracarboxylate anion). Single crystal X-ray diffraction analysis reveals that the material has a three-dimensional network, with two crystallographically independent Eu(III) ions adopting different coordination geometries. This structure presents one of the Btec4- anions acting as a μ8-bridging linker, with the carboxylate groups in distinct connection to Eu(III) ions, culminating into an unknown coordination mode for the linker. The results of thermogravimetric analyses indicate that the MOF has high thermal stability, with this characteristic being of great interest for the application of these compounds in several fields such as catalysis and photonics. The luminescent properties showed that the Eu(III) ions are a local-spectroscopic probe, with the compound presenting a red emission when excited in the UV spectral region with absolute emission quantum yield values of 0.48 ± 0.05. The thermal dependence on the intensity of the transitions originating from the 7F1 level, especially the 7F1 → 5D1 transition, was studied. These results opens the possibility to test this MOF [Eu2(Btec)1.5(H2O)]n in the field of molecular thermometry.

  14. Upgraded 1.56 microm lidar at IMK-IFU with 0.28 J/pulse.

    Science.gov (United States)

    Trickl, Thomas

    2010-07-01

    The 1.56 microm eye-safe aerosol lidar at the Institut für Meteorologie und Klimaforschung was upgraded, which resulted in a doubled laser pulse energy of 0.28 J and an improved performance of the detection electronics. The high pulse energy, achieved by stimulated Raman backscattering of 0.9 J from a Nd:YAG laser in deuterium (33% conversion efficiency when neglecting the residual optical losses), was mainly achieved by improving the beam quality of the pump beam. The Stokes pulses showed a subnanosecond peak with some underlying 10 ns component. Because of the substantial increase in pulse energy, this reliable and simple method considerably gains in value. Examples are presented, demonstrating an operating range between 0.4 and more than 10 km for quasi-horizontal measurements.

  15. High-power noise-like pulse generation using a 1.56-µm all-fiber laser system.

    Science.gov (United States)

    Lin, Shih-Shian; Hwang, Sheng-Kwang; Liu, Jia-Ming

    2015-07-13

    We demonstrated an all-fiber, high-power noise-like pulse laser system at the 1.56-µm wavelength. A low-power noise-like pulse train generated by a ring oscillator was amplified using a two-stage amplifier, where the performance of the second-stage amplifier determined the final output power level. The optical intensity in the second-stage amplifier was managed well to avoid not only the excessive spectral broadening induced by nonlinearities but also any damage to the device. On the other hand, the power conversion efficiency of the amplifier was optimized through proper control of its pump wavelength. The pump wavelength determines the pump absorption and therefore the power conversion efficiency of the gain fiber. Through this approach, the average power of the noise-like pulse train was amplified considerably to an output of 13.1 W, resulting in a power conversion efficiency of 36.1% and a pulse energy of 0.85 µJ. To the best of our knowledge, these amplified pulses have the highest average power and pulse energy for noise-like pulses in the 1.56-µm wavelength region. As a result, the net gain in the cascaded amplifier reached 30 dB. With peak and pedestal widths of 168 fs and 61.3 ps, respectively, for the amplified pulses, the pedestal-to-peak intensity ratio of the autocorrelation trace remains at the value of 0.5 required for truly noise-like pulses.

  16. Plasmid pEC156, a Naturally Occurring Escherichia coli Genetic Element That Carries Genes of the EcoVIII Restriction-Modification System, Is Mobilizable among Enterobacteria.

    Science.gov (United States)

    Werbowy, Olesia; Kaczorowski, Tadeusz

    2016-01-01

    Type II restriction-modification systems are ubiquitous in prokaryotes. Some of them are present in naturally occurring plasmids, which may facilitate the spread of these systems in bacterial populations by horizontal gene transfer. However, little is known about the routes of their dissemination. As a model to study this, we have chosen an Escherichia coli natural plasmid pEC156 that carries the EcoVIII restriction modification system. The presence of this system as well as the cis-acting cer site involved in resolution of plasmid multimers determines the stable maintenance of pEC156 not only in Escherichia coli but also in other enterobacteria. We have shown that due to the presence of oriT-type F and oriT-type R64 loci it is possible to mobilize pEC156 by conjugative plasmids (F and R64, respectively). The highest mobilization frequency was observed when pEC156-derivatives were transferred between Escherichia coli strains, Enterobacter cloacae and Citrobacter freundii representing coliform bacteria. We found that a pEC156-derivative with a functional EcoVIII restriction-modification system was mobilized in enterobacteria at a frequency lower than a plasmid lacking this system. In addition, we found that bacteria that possess the EcoVIII restriction-modification system can efficiently release plasmid content to the environment. We have shown that E. coli cells can be naturally transformed with pEC156-derivatives, however, with low efficiency. The transformation protocol employed neither involved chemical agents (e.g. CaCl2) nor temperature shift which could induce plasmid DNA uptake.

  17. Plasmid pEC156, a Naturally Occurring Escherichia coli Genetic Element That Carries Genes of the EcoVIII Restriction-Modification System, Is Mobilizable among Enterobacteria.

    Directory of Open Access Journals (Sweden)

    Olesia Werbowy

    Full Text Available Type II restriction-modification systems are ubiquitous in prokaryotes. Some of them are present in naturally occurring plasmids, which may facilitate the spread of these systems in bacterial populations by horizontal gene transfer. However, little is known about the routes of their dissemination. As a model to study this, we have chosen an Escherichia coli natural plasmid pEC156 that carries the EcoVIII restriction modification system. The presence of this system as well as the cis-acting cer site involved in resolution of plasmid multimers determines the stable maintenance of pEC156 not only in Escherichia coli but also in other enterobacteria. We have shown that due to the presence of oriT-type F and oriT-type R64 loci it is possible to mobilize pEC156 by conjugative plasmids (F and R64, respectively. The highest mobilization frequency was observed when pEC156-derivatives were transferred between Escherichia coli strains, Enterobacter cloacae and Citrobacter freundii representing coliform bacteria. We found that a pEC156-derivative with a functional EcoVIII restriction-modification system was mobilized in enterobacteria at a frequency lower than a plasmid lacking this system. In addition, we found that bacteria that possess the EcoVIII restriction-modification system can efficiently release plasmid content to the environment. We have shown that E. coli cells can be naturally transformed with pEC156-derivatives, however, with low efficiency. The transformation protocol employed neither involved chemical agents (e.g. CaCl2 nor temperature shift which could induce plasmid DNA uptake.

  18. Plasmid pEC156, a Naturally Occurring Escherichia coli Genetic Element That Carries Genes of the EcoVIII Restriction-Modification System, Is Mobilizable among Enterobacteria

    Science.gov (United States)

    Werbowy, Olesia; Kaczorowski, Tadeusz

    2016-01-01

    Type II restriction-modification systems are ubiquitous in prokaryotes. Some of them are present in naturally occurring plasmids, which may facilitate the spread of these systems in bacterial populations by horizontal gene transfer. However, little is known about the routes of their dissemination. As a model to study this, we have chosen an Escherichia coli natural plasmid pEC156 that carries the EcoVIII restriction modification system. The presence of this system as well as the cis-acting cer site involved in resolution of plasmid multimers determines the stable maintenance of pEC156 not only in Escherichia coli but also in other enterobacteria. We have shown that due to the presence of oriT-type F and oriT-type R64 loci it is possible to mobilize pEC156 by conjugative plasmids (F and R64, respectively). The highest mobilization frequency was observed when pEC156-derivatives were transferred between Escherichia coli strains, Enterobacter cloacae and Citrobacter freundii representing coliform bacteria. We found that a pEC156-derivative with a functional EcoVIII restriction-modification system was mobilized in enterobacteria at a frequency lower than a plasmid lacking this system. In addition, we found that bacteria that possess the EcoVIII restriction-modification system can efficiently release plasmid content to the environment. We have shown that E. coli cells can be naturally transformed with pEC156-derivatives, however, with low efficiency. The transformation protocol employed neither involved chemical agents (e.g. CaCl2) nor temperature shift which could induce plasmid DNA uptake. PMID:26848973

  19. Study of sorption mechanisms of europium(3) and uranium(6) ions on clays : impact of silicates; Etude des mecanismes de retention des ions U(6) et Eu(3) sur les argiles: influence des silicates

    Energy Technology Data Exchange (ETDEWEB)

    Kowal-Fouchard, A

    2002-11-01

    Bentonite clay has been selected as a potential buffer or backfill material in a number of disposal programmes for high level waste. In order to enhance the thermodynamic database of sorption phenomena at the solid-water interface, we have investigated sorption mechanisms of europium(III) and uranium(VI) ions onto montmorillonite and bentonite. Thermodynamic data were obtained for different ions concentrations, different background electrolytes and different ionic strengths. The structural identification of the surface complexes and sorption sites was carried out using two spectroscopies, XPS and TRLIFS, while sorption edges were performed using batch experiments. However, clays are complex minerals and in order to understand these sorption mechanisms we have studied europium(III) and uranium(VI) retention on a silica and an alumina because these solids are often considered as basic components of clays. The comparison of structural results shows that europium ions are significantly sorbed on permanently charged sites of clay until pH 7. But this ion is also sorbed on {identical_to}SiOH and {identical_to}AlOH sites of montmorillonite at pH higher than 6. Uranyl ions sorption on montmorillonite is mainly explained by retention of three complexes on {identical_to}SiOH sites. Moreover, we have shown that nitrate ions and dissolved silicates affect on uranium(VI) sorption mechanisms onto alumina. Nevertheless, uranyl ions sorption on montmorillonite and bentonite only decreases with increasing carbonate concentration. Finally, all the sorption edges were then modeled using these results and a surface complexation model (2 pK and constant capacitance models). (author)

  20. Distribution of micro-amounts of europium in the two-phase water–HCl–nitrobenzene–N,N’-dimethyl-N,N’-diphenyl-2,6-di-picolinamide–hydrogen dicarbollylcobaltate extraction system

    Directory of Open Access Journals (Sweden)

    EMANUEL MAKRLÍK

    2009-07-01

    Full Text Available Extraction of micro-amounts of europium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B- in the presence of N,N’-dimethyl-N,N’-diphenyl-2,6-dipicolinamide (MePhDPA, L was investigated. The equilibrium data were explained assuming that the species HL+, HL+2, HL3+2 and HL3+3 are extracted into the organic phase. The values of the extraction and stability constants of the species in nitrobenzene saturated with water were determined.

  1. Study of fish attraction by platform THE 156, BMCAL4-BA-Brazil; Estudo sobre a atracao de peixes na plataforma de perfuracao THE 156, BMCAL4-Ba-Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Bertoncini, Athila A.; Jardweski, Cleiton F.; Daros, Felippe; Diogo, Hugo R.L.; Fraga, Adriana P.C. [SOMA, Belo Horizonte, MG (Brazil); Sampaio, Claudio L. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil)

    2008-07-01

    To monitor the attraction effect of THE156 platform over the fisheries resources in shallow waters, close to coral reefs, at BM-CAL-4, underwater visual census (UVC) and video-census methods were used, along five reefs and the platform during three distinct moments: before, during and after the drilling operations. A total of 124 species were identified. The richest fish families were: Serranidae, Labridae, Haemulidae, Scaridae, Lutjanidae and Pomacentridae. Multi dimensional scaling analysis considering distinct moments and areas, pointed out three main groups. The largest, composed by natural reefs, and two other groups composed by the platform in distinct moments, before and after the operations. Since the template was left in the area after the drilling operations, this was the main factor contributing to create the latest group. This structure allowed an increment in abundance and species richness, creating a singular fish community, which inhabited the platform previously during its operation. The sampling design had as a hypothesis, an scale of impact in which if the platform could cause any impact over the fish communities, the closer reefs would be the first ones to be impacted. Considering this strategy, the differences found during the monitoring period, which occurred in the most southern reef area, do not characterize a direct impact of the platform over the natural reefs. (author)

  2. Europium-doped Gd2O3 nanotubes cause the necrosis of primary mouse bone marrow stromal cells through lysosome and mitochondrion damage.

    Science.gov (United States)

    Jin, Yi; Chen, Shizhu; Duan, Jianlei; Jia, Guang; Zhang, Jinchao

    2015-05-01

    With the wide applications of europium-doped Gd2O3 nanoparticles (Gd2O3:Eu(3+) NPs) in biomedical fields, it will inevitably increase the chance of human exposure. It was reported that Gd2O3:Eu(3+) NPs could accumulate in bone. However, there have been few reports about the potential effect of Gd2O3:Eu(3+) NPs on bone marrow stromal cells (BMSCs). In this study, the Gd2O3:Eu(3+) nanotubes were prepared and characterized by powder X-ray diffraction (XRD), photoluminescence (PL) excitation and emission spectra, scanning electron microscope (SEM), and transmission electron microscopy (TEM). The cytotoxicity of Gd2O3:Eu(3+) nanotubes on BMSCs and the associated mechanisms were further studied. The results indicated that they could be uptaken into BMSCs by an energy-dependent and macropinocytosis-mediated endocytosis process, and primarily localized in lysosome. Gd2O3:Eu(3+) nanotubes effectively inhibited the viability of BMSCs in concentration and time-dependent manners. A significant increase in the percentage of late apoptotic/necrotic cells, lactate dehydrogenase (LDH) leakage and the number of PI-stained cells was found after BMSCs were treated by 10, 20, and 40μg/mL of Gd2O3:Eu(3+) nanotubes for 12h. No obvious DNA ladders were detected, but a dispersed band was observed. The above results revealed that Gd2O3:Eu(3+) nanotubes could trigger cell death by necrosis instead of apoptosis. Two mechanisms were involved in Gd2O3:Eu(3+) nanotube-induced BMSCs necrosis: lysosomal rupture and release of cathepsins B; and the overproduction of reactive oxygen species (ROS) injury to the mitochondria and DNA. The study provides novel evidence to elucidate the toxicity mechanisms and may be beneficial to more rational applications of these nanomaterials in the future. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Europium-decorated graphene quantum dots as a fluorescent probe for label-free, rapid and sensitive detection of Cu(2+) and L-cysteine.

    Science.gov (United States)

    Lin, Liping; Song, Xinhong; Chen, Yiying; Rong, Mingcong; Wang, Yiru; Zhao, Li; Zhao, Tingting; Chen, Xi

    2015-09-03

    In this work, europium-decorated graphene quantum dots (Eu-GQDs) were prepared by treating three-dimensional Eu-decorated graphene (3D Eu-graphene) via a strong acid treatment. Various characterizations revealed that Eu atoms were successfully complexed with the oxygen functional groups on the surface of graphene quantum dots (GQDs) with the atomic ratio of 2.54%. Compared with Eu free GQDs, the introduction of Eu atoms enhanced the electron density and improved the surface chemical activities of Eu-GQDs. Therefore, the obtained Eu-GQDs were used as a novel "off-on" fluorescent probe for the label-free determination of Cu(2+) and l-cysteine (L-Cys) with high sensitivity and selectivity. The fluorescence intensity of Eu-GQDs was quenched in the presence of Cu(2+) owing to the coordination reaction between Cu(2+) and carboxyl groups on the surface of the Eu-GQDs. The fluorescence intensity of Eu-GQDs recovered with the subsequent addition of L-Cys because of the strong affinity of Cu(2+) to L-Cys via the Cu-S bond. The experimental results showed that the fluorescence variation of the proposed approach had a good linear relationship in the range of 0.1-10 μM for Cu(2+) and 0.5-50 μM for L-Cys with corresponding detection limits of 0.056 μM for Cu(2+) and 0.31 μM for L-Cys. The current approach also displayed a special response to Cu(2+) and L-Cys over the other co-existing metal ions and amino acids, and the results obtained from buffer-diluted serum samples suggested its applicability in biological samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Sensitive detection of influenza viruses with Europium nanoparticles on an epoxy silica sol-gel functionalized polycarbonate-polydimethylsiloxane hybrid microchip.

    Science.gov (United States)

    Liu, Jikun; Zhao, Jiangqin; Petrochenko, Peter; Zheng, Jiwen; Hewlett, Indira

    2016-12-15

    In an effort to develop new tools for diagnosing influenza in resource-limited settings, we fabricated a polycarbonate (PC)-polydimethylsiloxane (PDMS) hybrid microchip using a simple epoxy silica sol-gel coating/bonding method and employed it in sensitive detection of influenza virus with Europium nanoparticles (EuNPs). The incorporation of sol-gel material in device fabrication provided functionalized channel surfaces ready for covalent immobilization of primary antibodies and a strong bonding between PDMS substrates and PC supports without increasing background fluorescence. In microchip EuNP immunoassay (µENIA) of inactivated influenza viruses, replacing native PDMS microchips with hybrid microchips allowed the achievement of a 6-fold increase in signal-to-background ratio, a 12-fold and a 6-fold decreases in limit-of-detection (LOD) in influenza A and B tests respectively. Using influenza A samples with known titers, the LOD of influenza µENIA on hybrid microchips was determined to be ~10(4) TCID50 titer/mL and 10(3)-10(4) EID50 titer/mL. A comparison test indicated that the sensitivity of influenza µENIA enhanced using the hybrid microchips even surpassed that of a commercial laboratory influenza ELISA test. In addition to the sensitivity improvement, assay variation was clearly reduced when hybrid microchips instead of native PDMS microchips were used in the µENIA tests. Finally, infectious reference viruses and nasopharyngeal swab patient specimens were successfully tested using μENIA on hybrid microchip platforms, demonstrating the potential of this unique microchip nanoparticle assay in clinical diagnosis of influenza. Meanwhile, the tests showed the necessity of using nucleic acid confirmatory tests to clarify ambiguous test results obtained from prototype or developed point-of-care testing devices for influenza diagnosis. Published by Elsevier B.V.

  5. A visible-light-excited europium(III) complex-based luminescent probe for visualizing copper ions and hydrogen sulfide in living cells

    Science.gov (United States)

    Wang, Yiren; Wang, Huan; Yang, Mei; Yuan, Jingli; Wu, Jing

    2018-01-01

    Development of visible-light-excited lanthanide (III) complex-based luminescent probes is highly appealing due to their superiority of less damage to the living biosystems over the conventional UV-light-excited ones. In this work, a visible-light-excited europium (III) complex-based luminescent probe, BPED-BHHCT-Eu3+-BPT, has been designed and synthesized by conjugating the Cu2+-binding N,N-bis(2-pyridylmethyl)ethanediamine (BPED) to a tetradentate β-diketone ligand 4,4‧-bis(1″,1″,1″,2″,2″,3″,3″-heptafluoro-4″,6″-hexanedione-6″-yl)chlorosulfo-o-terphenyl (BHHCT) and coordinating with a coligand 2-(N,N-diethylanilin-4-yl)-4,6-bis(pyrazol-1-yl)-1,3,5-triazine) (BPT) for the time-gated luminescence detection of Cu2+ ions and hydrogen sulfide (H2S) in living cells. BPED-BHHCT-Eu3+-BPT exhibited a sharp excitation peak at 407 nm and a wide excitation window extending to beyond 460 nm. Upon its reaction with Cu2+ ions, the luminescence of BPED-BHHCT-Eu3+-BPT was efficiently quenched, which could be reversibly restored by the addition of H2S due to the strong affinity between Cu2+ ions and H2S. The "on-off-on" type luminescence behavior of BPED-BHHCT-Eu3+-BPT towards Cu2+ ions and H2S enabled the sensing of the two species with high sensitivity and selectivity. The performances of BPED-BHHCT-Eu3+-BPT for visualizing intracellular Cu2+ ions and H2S were investigated, and the results have demonstrated the practical applicability of the probe for molecular imaging of cells.

  6. Biochemical and structural characterization of quinoprotein aldose sugar dehydrogenase from Thermus thermophilus HJ6: Mutational analysis of Tyr156 in the substrate-binding site.

    Science.gov (United States)

    Kim, Han-Woo; Wang, Ji-Yeon; Lee, Ji-Yeon; Park, Ae-Kyung; Park, Hyun; Jeon, Sung-Jong

    2016-10-15

    The gene encoding a quinoprotein aldose sugar dehydrogenase (ASD) from Thermus thermophilus HJ6 (Tt_ASD) was cloned and sequenced; it comprised 1059 nucleotides encoding a protein containing 352 amino acids that had a predicted molecular mass of 38.9 kDa. The deduced amino acid sequence showed 42.9% and 33.9% identities to the ASD proteins from Pyrobaculum aerophilum and Escherichia coli, respectively. The biochemical properties of Tt_ASD were characterized. The optimum pH for the oxidation of glucose was 7.0-7.5 and the optimum temperature was 70 °C. The half-life of heat inactivation for the apoenzyme was about 25 min at 85 °C. The enzyme was highly thermostable, and the activity of the pyrroloquinoline quinone-bound holoenzyme was not lost after incubation at 85 °C for 100 min. Tt_ASD could oxidize various sugars, including hexoses, pentoses, disaccharides, and polysaccharides, in addition to alcohols. Structural analysis suggested that Tyr156 would be the substrate-binding residue. Two mutants, Y156A and Y156K, had impaired activities and affinities for all substrates and completely lost their activities for alcohols. This structural and mutational analysis of Tt_ASD demonstrates the crucial role of Tyr156 in determining substrate specificity. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Application and further characterization of the snap bean S156/R123 ozone biomonitoring system in relation to ambient air temperature

    Science.gov (United States)

    Increased mixing ratios of ground-level ozone threaten individual plants, plant communities and ecosystems. In this sense, ozone biomonitoring is of great interest. The ozone-sensitive S156 and the ozone-tolerant R123 genotypes of snap bean (Phaseolus vulgaris L.) have been proposed as a potential t...

  8. The Polymorphism of DNA Repair Gene ERCC2/XPD Arg156Arg and Susceptibility to Breast Cancer in a Chinese Population

    DEFF Research Database (Denmark)

    Yin, J. Y.; Liang, D. H.; Vogel, Ulla Birgitte

    2009-01-01

    the association between ERCC2/XPD Arg156Arg and susceptibility to breast cancer in a Chinese population, we conducted a hospital-based case-control study consisting of 129 patients with breast cancer and 205 controls matched by age, gender, and ethnicity. PCR-RFLP was used for genotyping. No associations were...

  9. Thesaurus for histopathological findings in publically available reports of repeated-dose oral toxicity studies in rats for 156 chemicals.

    Science.gov (United States)

    Nishikawa, Satoshi; Yamashita, Tatsuhiro; Imai, Toshio; Yoshida, Midori; Sakuratani, Yuki; Yamada, Jun; Maekawa, Akihiko; Hayashi, Makoto

    2010-06-01

    Because histopathological findings are often conclusive indicators of the toxicities of chemicals, standardization of nomenclature and construction of a thesaurus for histopathological findings are important for the comparative evaluation of histopathological data from repeated-dose toxicity studies (RTS). However, terms for histopathological findings have not been standardized and different technical terms are used to indicate almost the same thing in RTS. The present study was conducted to construct an easy-to-use thesaurus for histopathological findings in order to facilitate hazard assessments of untested chemicals by the category approach using knowledge of the toxicity of analogue chemicals. We used reports of 28-day RTS, conducted on rats by gavage, which were posted on the websites of the National Institute of Health Sciences (NIHS) and the National Institute of Technology and Evaluation (NITE). The histopathological data were from 156 reports on RTS conducted by 13 institutions in Japan. As a result of this study, major parts of the thesaurus were devoted to the findings in the liver, kidney, stomach, adrenal, thyroid and testis; the first three organs are known to be the main targets of chemicals. We also decided that findings such as swelling and enlargement of hepatocytes should be categorized as synonyms for terms meaning hypertrophy. Our thesaurus will be helpful in assessing or screening new untested chemicals by the category approach using knowledge of the toxicities of analogues of the new chemical. The RTS database with this thesaurus will be made publically available in 2012.

  10. 156 - 159 Adegbusi

    African Journals Online (AJOL)

    DR. AMINU

    cells of the central nervous system, the brain. Emphasis is given to the relevance of pyridoxal phosphate (PLP) ... diverse biological effects, with certain intermediates acting as neurotoxins, others as neuroprotective .... whole wheat and rye bread inhibit the production of serotonin. Research also suggests consuming a diet ...

  11. 153 - 156 MYushau

    African Journals Online (AJOL)

    DR. AMIN

    2011-06-01

    Oyeleke and Manga,. 2008). Test for saponins. Half gram (0.5g) of the powder of the two plants was taken in separate test tubes to which 5.0ml of distilled water was added and vigorously shaken. A persistent froth that lasted for ...

  12. Chemical species of europium (III) in ionic force media 0.02M, 0.1M, and 0.7M NaClO{sub 4} at 298 K; Especies quimicas del europio (III) en medios de fuerza ionica 0.02M, 0.1M y 0.7M NaClO{sub 4} a 298 K

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez R, E.; Jimenez R, M.; Solache R, M. [Instituto Nacional de Investigaciones Nucleares, Departamento de Quimica, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

    2000-07-01

    In order to know the effects of the controlled or accidental liberation of the europium in the environment, it is necessary to know its chemical behavior in found conditions in oceans, ground and surface water. The behavior of this element in these environments can be controlled mainly by the hydrolysis and its interaction with inorganic and organic ions. (Author)

  13. Synthesis, single-crystal structure determination, and vibrational spectroscopy of the europium borate Eu[B{sub 6}O{sub 8}(OH){sub 5}].H{sub 3}BO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Ortner, Teresa S.; Wurst, Klaus; Huppertz, Hubert [Institut fuer Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universitaet Innsbruck (Austria); Seibald, Markus [OSRAM GmbH, Corporate Innovation, Schwabmuenchen (Germany); Joachim, Bastian [Institut fuer Mineralogie und Petrographie, Leopold-Franzens-Universitaet Innsbruck (Austria)

    2016-07-15

    The new europium borate Eu[B{sub 6}O{sub 8}(OH){sub 5}].H{sub 3}BO{sub 3} was obtained by hydrothermal synthesis from europium nitrate hydrate and boric acid. The compound crystallizes in the triclinic space group P1 (no. 2) with the lattice parameters a = 681.59(3), b = 714.17(3), c = 1271.88(6) pm, α = 96.02(1), β = 98.60(1), γ = 101.73(1) (Z = 2). The structure of Eu[B{sub 6}O{sub 8}(OH){sub 5}].H{sub 3}BO{sub 3} is isotypic to that of the samarium borate Sm[B{sub 6}O{sub 8}(OH){sub 5}].H{sub 3}BO{sub 3} and is built up from tetrahedral BO{sub 4} and trigonal-planar BO{sub 3} units, both of which are protonated at terminal and bridging oxygen positions. Boric acid molecules reside between the borate layers. Through hydrogen bonding, the structure forms a three-dimensional network. In channels down [110], the Eu{sup 3+} cations are eightfold coordinated by oxygen ions. The compound was also characterized by IR and Raman spectroscopy, and it shows typical Eu{sup 3+} line emission. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Rapid and sensitive lateral flow immunoassay method for determining alpha fetoprotein in serum using europium (III) chelate microparticles-based lateral flow test strips

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Rong-Liang; Xu, Xu-Ping; Liu, Tian-Cai; Zhou, Jian-Wei; Wang, Xian-Guo; Ren, Zhi-Qi [Institute of Antibody Engineering, School of Biotechnology, Southern Medical University, Guangzhou 510515, Guangdong (China); Hao, Fen [DaAn Gene Co. Ltd. of Sun Yat-sen University, 19 Xiangshan Road, Guangzhou 510515 (China); Wu, Ying-Song, E-mail: wg@smu.edu.cn [Institute of Antibody Engineering, School of Biotechnology, Southern Medical University, Guangzhou 510515, Guangdong (China)

    2015-09-03

    Alpha-fetoprotein (AFP), a primary marker for many diseases including various cancers, is important in clinical tumor diagnosis and antenatal screening. Most immunoassays provide high sensitivity and accuracy for determining AFP, but they are expensive, often complex, time-consuming procedures. A simple and rapid point-of-care system that integrates Eu (III) chelate microparticles with lateral flow immunoassay (LFIA) has been developed to determine AFP in serum with an assay time of 15 min. The approach is based on a sandwich immunoassay performed on lateral flow test strips. A fluorescence strip reader was used to measure the fluorescence peak heights of the test line (H{sub T}) and the control line (H{sub C}); the H{sub T}/H{sub C} ratio was used for quantitation. The Eu (III) chelate microparticles-based LFIA assay exhibited a wide linear range (1.0–1000 IU mL{sup −1}) for AFP with a low limit of detection (0.1 IU mL{sup −1}) based on 5ul of serum. Satisfactory specificity and accuracy were demonstrated and the intra- and inter-assay coefficients of variation (CV) for AFP were both <10%. Furthermore, in the analysis of human serum samples, excellent correlation (n = 284, r = 0.9860, p < 0.0001) was obtained between the proposed method and a commercially available CLIA kit. Results indicated that the Eu (III) chelate microparticles-based LFIA system provided a rapid, sensitive and reliable method for determining AFP in serum, indicating that it would be suitable for development in point-of-care testing. - Highlights: • Europium (III) chelate microparticles was used as a label for LIFA. • Quantitative detection by using H{sub T}/H{sub C} ratio was achieved. • LIFA for simple and rapid AFP detection in human serum. • The sensitivity and linearity was more excellent compared with QD-based ICTS. • This method could be developed for rapid point-of-care screening.

  15. Crystal structure of monoclinic samarium and cubic europium sesquioxides and bound coherent neutron scattering lengths of the isotopes {sup 154}Sm and {sup 153}Eu

    Energy Technology Data Exchange (ETDEWEB)

    Kohlmann, Holger [Leipzig Univ. (Germany). Inst. of Inorganic Chemistry; Hein, Christina; Kautenburger, Ralf [Saarland Univ., Saarbruecken (Germany). Inorganic Solid State Chemistry; Hansen, Thomas C.; Ritter, Clemens [Institut Laue-Langevin, Grenoble (France); Doyle, Stephen [Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen (Germany). Inst. for Synchrotron Radiation (ISS)

    2016-11-01

    The crystal structures of monoclinic samarium and cubic europium sesquioxide, Sm{sub 2}O{sub 3} and Eu{sub 2}O{sub 3}, were reinvestigated by powder diffraction methods (laboratory X-ray, synchrotron, neutron). Rietveld analysis yields more precise structural parameters than previously known, especially for oxygen atoms. Interatomic distances d(Sm-O) in Sm{sub 2}O{sub 3} range from 226.3(4) to 275.9(2) pm [average 241.6(3) pm] for the monoclinic B type Sm{sub 2}O{sub 3} [space group C2/m, a = 1418.04(3) pm, b = 362.660(7) pm, c = 885.48(2) pm, β = 100.028(1) ], d(Eu-O) in Eu{sub 2}O{sub 3} from 229.9(2) to 238.8(2) pm for the cubic bixbyite (C) type [space group Ia anti 3, a = 1086.87(1) pm]. Neutron diffraction at 50 K and 2 K did not show any sign for magnetic ordering in Sm{sub 2}O{sub 3}. Isotopically enriched {sup 154}Sm{sub 2}O{sub 3} and {sup 153}Eu{sub 2}O{sub 3} were used for the neutron diffraction work because of the enormous absorption cross section of the natural isotopic mixtures for thermal neutrons. The isotopic purity was determined by inductively coupled plasma - mass spectrometry to be 98.9% for {sup 154}Sm and 99.8% for {sup 153}Eu. Advanced analysis of the neutron diffraction data suggest that the bound coherent scattering lengths of {sup 154}Sm and {sup 153}Eu need to be revised. We tentatively propose b{sub c}({sup 154}Sm) = 8.97(6) fm and b{sub c}({sup 153}Eu) = 8.85(3) fm for a neutron wavelength of 186.6 pm to be better values for these isotopes, showing up to 8% deviation from accepted literature values. It is shown that inaccurate scattering lengths may result in severe problems in crystal structure refinements causing erroneous structural details such as occupation parameters, which might be critically linked to physical properties like superconductivity in multinary oxides.

  16. The adsorption of europium to colloidal iron oxyhydroxides and quartz - the impact of pH and an aquatic fulvic acid

    Energy Technology Data Exchange (ETDEWEB)

    Ledin, A. [Dept. of Water and Environmental Studies, Linkoeping Univ. (Sweden); Karlsson, S. [Dept. of Water and Environmental Studies, Linkoeping Univ. (Sweden); Dueker, A. [Dept. of Water and Environmental Studies, Linkoeping Univ. (Sweden); Allard, B. [Dept. of Water and Environmental Studies, Linkoeping Univ. (Sweden)

    1994-12-31

    The adsorption of europium to colloidal Fe{sub 2}O{sub 3}, FeOOH, Fe(OH){sub 3} and SiO{sub 2} was investigated as a function of pH and the presence of an aquatic fulvic acid (FA). The colloids were present at concentrations repressentative of the upper levels of natural waters (50-500 mg/l). Measurements with Photon Correlation Spectroscopy showed size distribution typically within the ranges 200-700 nm, 40-400 nm and 50-300 nm for Fe{sub 2}O{sub 3}, FeOOH and SiO{sub 2}, respectively, while the amorphous Fe(OH){sub 3} formed relatively large particles (>1000 nm; outside the range of the method for measurements of size distribution). Total concentrations of Eu and the fulvic acid were 10{sup -8} mol l{sup -1} and 2 mg l{sup -1}, respectively. The adsorption was affected by pH, the composition of the colloidal phase as well as the presence of fulvic acid. The uptake was almost quantitative in the Fe-systems at pH>5.5-6, with 50% uptake at pH of 4.5-5.5 (4-5 units below pH{sub zpc}). For quartz, the maximum adsorption was around 90% (at pH 9), with 50% adsorption at pH 7 (4 pH units above pH{sub zpc}). The adsorption can not be related to coulombic attraction between the surfaces and the metal species alone, but rather to a specific chemical adsorption, where the pH-dependence would be related to the distribution of Eu between different species (on the surface and in solution). The presence of FA slightly increased the absorption in the lower pH range, corresponding to an adsorption of Eu-fulvate complexes. The adsorption was reaching 100% at higher pH values in the Fe(OH){sub 3} system, while it was decreased in the other three systems compared to the experiments without FA. The decrease could be attributed to competition between inorganic Eu species and the FA-molecules about sites on the surfaces, an effect not obvious in the Fe(OH){sub 3}-systems due to the much larger surface area available. (orig./MBS)

  17. Self-welding evaluation of stellite 6 and stellite 156 in flowing sodium. [850-1140/sup 0/F at stresses from 6000-16000 psi

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J.Y.; Schrock, S.L.; Johnson, R.N.

    1977-01-01

    The self-welding behavior of two similar materials, Stellite 6 and Stellite 156, in sodium are discussed. The materials were tested at temperatures from 850 to 1140/sup 0/F for time periods up to six-months while immersed in flowing sodium. Contact stresses ranged from 6000 psi to 16,000 psi on contact areas from 0.35 to 0.47 square inches. All separation tests to determine the extent of self-welding were conducted in a tensile mode. The surface morphologies of the samples before and after each test were measured. At temperatures of 1115/sup 0/F and above, almost all the Stellite 6 specimens indicated a significant tendency toward self-welding within a relatively short period of time (one week). Stellite 156 couples also developed a strong self-weld bond at 1060/sup 0/F after six-month exposure.

  18. Substitutions at NS3 Residue 155, 156, or 168 of Hepatitis C Virus Genotypes 2 to 6 Induce Complex Patterns of Protease Inhibitor Resistance

    DEFF Research Database (Denmark)

    Jensen, Sanne B.; Serre, Stephanie B. N.; Humes, Daryl G.

    2015-01-01

    Various protease inhibitors (PIs) are currently becoming available for treatment of hepatitis C virus (HCV). For genotype 1, substitutions at NS3 protease positions 155, 156, and 168 are main determinants of PI resistance. For other genotypes, similar substitutions were selected during PI treatment...... to nine PIs (telaprevir, boceprevir, simeprevir, asunaprevir, vaniprevir, faldaprevir, paritaprevir, deldeprevir, and grazoprevir) in Huh7.5 cells. We found that most variants showed decreased fitness compared to original viruses. Overall, R155K-, A156G/S-, and D/Q168A/E/H/N/V-variants showed highest...... resistant. For the remaining PIs, most genotype 2-, 4-, 5-, and 6-, but not genotype 3-variants, showed varying resistance levels. Overall, grazoprevir (MK-5172) had the highest efficacy against original viruses and variants.This is the first comprehensive study revealing the impact of described key PI...

  19. Occurrence of plant sensitivity among patients of photodermatoses: A control-matched study of 156 cases from New Delhi

    Directory of Open Access Journals (Sweden)

    Kar Hemanta

    2009-01-01

    Full Text Available Background: Photodermatitis is an abnormal response to ultraviolet radiation (UVR. The photoallergic contact dermatitis caused by plant allergens is a serious cause of morbidity in India. Airborne contact dermatitis is the classical presentation of plant-induced dermatosis, which may become difficult to differentiate from chronic actinic dermatitis in chronic cases. The rapid growth of parthenium weed in India and its ill effects on the population make it important to detect all cases of parthenium sensitivity, which in some cases might simulate photodermatitis. Aims: This study aims to detect the occurrence of plant sensitivity and photosensitivity in idiopathic-acquired photodermatoses, airborne contact dermatitis and general population taken as controls. Methods: One hundred and fifty six consecutive patients suffering from polymorphic light eruption (PMLE, chronic actinic dermatitis (CAD and airborne contact dermatitis (ABCD were enrolled in the study over a period of three years (June 2004 to May 2007. An equal number of age and sex matched healthy subjects were enrolled in the study as controls. All the patients were subjected to detailed history taking, clinical examination and histopathological examination for diagnosis. Patch and photopatch testing were perfomed in all the patients and healthy controls for detection of allergic and photoallergic reactions to parthenium, xanthium and chrysanthemum plant antigens and control antigens. Results: Out of 156 patients enrolled in the study, 78 (50% had CAD, 67 (42.9% had PMLE and 11 (7.05% had ABCD. The occurrence of parthenium/xanthium allergy and photoallergy, either to parthenium or both was most commonly found in ABCD (72.7%, followed by CAD (32%. In PMLE 4.5% cases showed photoallergy. Only 1.9% in the control group showed sensitivity to parthenium and xanthium. Conclusion: This study indicates that parthenium (and possibly xanthium may act as important environmental factors in the

  20. Radar, Optical, and Infrared Observations of Equal-Mass Binary Near-Earth Asteroid (190166) 2005 UP156

    Science.gov (United States)

    Taylor, Patrick A.; Virkki, Anne; Warner, Brian; Aznar, Amadeo; Howell, Ellen S.; Vervack, Ronald J.; Crowell, Jenna L.; Hinkle, Mary; Venditti, Flaviane; Zambrano-Marin, Luisa Fernanda; Aponte-Hernandez, Betzaida; Rivera-Valentin, Edgard G.; Saran Bhiravarasu, Sriram; Rodriguez Sanchez-Vahamonde, Carolina; Harris, Alan William; Fernandez, Yanga R.; Marshall, Sean E.

    2017-10-01

    The binary nature of near-Earth asteroid (190166) 2005 UP156 was shown by distinctive mutual events in its optical lightcurves from 2017 May 4-23 (Warner & Harris, 2017; CBET 4394). The observed lightcurve period of 40.542 +/- 0.008 h agrees with the period determined in 2014 (Warner, 2015; Minor Planet Bulletin 42, 41-53), though no mutual events were noted at that time. An out-of-eclipse amplitude of 0.5 mag implies elongated shapes for the components. Radar observations with the Arecibo planetary radar system on 15 dates from 2017 June 2 to July 10 unambiguously revealed the roughly equal-size components of the binary system, only the third such system known among the near-Earth asteroids after (69230) Hermes (Margot et al., 2003; IAUC 8227) and 1994 CJ1 (Taylor et al., 2014; DPS 46, #409.03) out of more than 50 known near-Earth multiple-asteroid systems. Preliminary diameter estimates from radar images are no more than 1 km in the longest dimension for both components. Images at different orientations suggest elongated shapes with the long axes aligned, i.e., face-locked synchronous rotation, and an orbital period commensurate with the optical lightcurve period. The maximum observed separation between the components of 2.4 km places a lower limit on the semimajor axis of the system, though the projection effect should be minimal given the eclipsing nature of the lightcurves. Combined with the above upper limit on the diameters, the implied density of the system could be less than 1 g/cc, though the actual value will be sensitive to the true elongation of the shapes. Spectra of the system between 0.7 and 5.1 microns obtained with the NASA Infrared Telescope Facility on four dates between 2017 May 27 and July 19 suggest a Bus-DeMeo taxonomic type of S or Sq transitioning to a spectrum dominated by thermal emission beyond 3.5 microns with little variation over the two-month span of observations.

  1. Md-miR156ab and Md-miR395 Target WRKY Transcription Factors to Influence Apple Resistance to Leaf Spot Disease.

    Science.gov (United States)

    Zhang, Qiulei; Li, Yang; Zhang, Yi; Wu, Chuanbao; Wang, Shengnan; Hao, Li; Wang, Shengyuan; Li, Tianzhong

    2017-01-01

    MicroRNAs (miRNAs) are key regulators of gene expression that post-transcriptionally regulate transcription factors involved in plant physiological activities. Little is known about the effects of miRNAs in disease resistance in apple (Malus×domestica). We globally profiled miRNAs in the apple cultivar Golden Delicious (GD) infected or not with the apple leaf spot fungus Alternaria alternaria f. sp. mali (ALT1), and identified 58 miRNAs that exhibited more than a 2-fold upregulation upon ALT1 infection. We identified a pair of miRNAs that target protein-coding genes involved in the defense response against fungal pathogens; Md-miR156ab targets a novel WRKY transcription factor, MdWRKYN1, which harbors a TIR and a WRKY domain. Md-miR395 targets another transcription factor, MdWRKY26, which contains two WRKY domains. Real-time PCR analysis showed that Md-miR156ab and Md-miR395 levels increased, while MdWRKYN1 and MdWRKY26 expression decreased in ALT1-inoculated GD leaves; furthermore, the overexpression of Md-miR156ab and Md-miR395 resulted in a significant reduction in MdWRKYN1 and MdWRKY26 expression. To investigate whether these miRNAs and their targets play a crucial role in plant defense, we overexpressed MdWRKYN1 or knocked down Md-miR156ab activity, which in both cases enhanced the disease resistance of the plants by upregulating the expression of the WRKY-regulated pathogenesis-related (PR) protein-encoding genes MdPR3-1, MdPR3-2, MdPR4, MdPR5, MdPR10-1, and MdPR10-2. In a similar analysis, we overexpressed MdWRKY26 or suppressed Md-miR395 activity, and found that many PR protein-encoding genes were also regulated by MdWRKY26. In GD, ALT-induced Md-miR156ab and Md-miR395 suppress MdWRKYN1 and MdWRKY26 expression, thereby decreasing the expression of some PR genes, and resulting in susceptibility to ALT1.

  2. Effect of the ion force on the hydrolysis constants and of the solubility product of Europium; Efecto de la fuerza ionica sobre las constantes de hidrolisis y del producto de solubilidad del europio

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez R, M.; Ramirez G, J.J.; Solache R, M.; Rojas H, A. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-07-01

    A study on the behavior of the first hydrolysis constant {beta}{sub Eu,H}{sup l-0} and the constant of the solubility product Kps of the europium in front of the changes of the ion force: 0. 02 M, 0.1 M, 0.7M, 2M, 3M and 4M of sodium perchlorate, at 303 K. Experimentally the potentiometry and also radioactivity measures its were used. The specific interaction of ions theory (SIT) of Bronsted-Guggenheim-Scatchard allows the extrapolation of the values to infinite dilution and the results were: log {beta}{sub Eu,H}{sup l-0} = -7 36 and log K{sub sp}{sup l-0} = -24. 68. A discussion of the group of results with the data of the literature is presented. (Author)

  3. Sequence analysis of 96 genomic regions identifies distinct evolutionary lineages within CC156, the largest Streptococcus pneumoniae clonal complex in the MLST database.

    Directory of Open Access Journals (Sweden)

    Monica Moschioni

    Full Text Available Multi-Locus Sequence Typing (MLST of Streptococcus pneumoniae is based on the sequence of seven housekeeping gene fragments. The analysis of MLST allelic profiles by eBURST allows the grouping of genetically related strains into Clonal Complexes (CCs including those genotypes with a common descent from a predicted ancestor. However, the increasing use of MLST to characterize S. pneumoniae strains has led to the identification of a large number of new Sequence Types (STs causing the merger of formerly distinct lineages into larger CCs. An example of this is the CC156, displaying a high level of complexity and including strains with allelic profiles differing in all seven of the MLST loci, capsular type and the presence of the Pilus Islet-1 (PI-1. Detailed analysis of the CC156 indicates that the identification of new STs, such as ST4945, induced the merging of formerly distinct clonal complexes. In order to discriminate the strain diversity within CC156, a recently developed typing schema, 96-MLST, was used to analyse 66 strains representative of 41 different STs. Analysis of allelic profiles by hierarchical clustering and a minimum spanning tree identified ten genetically distinct evolutionary lineages. Similar results were obtained by phylogenetic analysis on the concatenated sequences with different methods. The identified lineages are homogenous in capsular type and PI-1 presence. ST4945 strains were unequivocally assigned to one of the lineages. In conclusion, the identification of new STs through an exhaustive analysis of pneumococcal strains from various laboratories has highlighted that potentially unrelated subgroups can be grouped into a single CC by eBURST. The analysis of additional loci, such as those included in the 96-MLST schema, will be necessary to accurately discriminate the clonal evolution of the pneumococcal population.

  4. Application and further characterization of the snap bean S156/R123 ozone biomonitoring system in relation to ambient air temperature.

    Science.gov (United States)

    Agathokleous, Evgenios; Saitanis, Costas J; Burkey, Kent O; Ntatsi, Georgia; Vougeleka, Vasiliki; Mashaheet, Alsayed M; Pallides, Andreas

    2017-02-15

    Increased mixing ratios of ground-level ozone (O3) threaten individual plants, plant communities and ecosystems. In this sense, O3 biomonitoring is of great interest. The O3-sensitive S156 and the O3-tolerant R123 genotypes of snap bean (Phaseolus vulgaris L.) have been proposed as a potential tool for active biomonitoring of ambient O3. In the present study, an O3 biomonitoring was conducted, with the S156/R123 tool, along with a monitoring of O3 and other environmental conditions in an urban area in Athens, Greece, during the growing seasons of 2012 and 2013. Plant yield was evaluated to assess the effectiveness of AOT40 in interpreting O3-induced phytotoxicity. Across the two genotypes, an approximately two times lower total number of pods - and consequently lower bulk mass of seeds - was found in 2012 than in 2013, although there was no significant difference in the final AOT40 between the two years. No significant differences were observed in the stomatal density or conductance between the two genotypes, whereas it was estimated that, in both genotypes, the abaxial leaf surface contributes 2.7 fold to O3 intake in comparison to the adaxial one. By testing the role of ambient air temperature in outdoor plant environment chambers (OPECs), it was found that increased temperature limits mature pod formation and complicates interpretation of O3 impacts in terms of S156/R123 yields ratios. This is the first study providing evidence for a hormetic response of plants to ambient air temperature. This study also points out the complexity of using yield as a measure of O3 impact across different environments with the snap bean system, whereas visible foliar injury is more consistently related to O3 effects. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Cs-miR156 is involved in the nitrogen form regulation of catechins accumulation in tea plant (Camellia sinensis L.).

    Science.gov (United States)

    Fan, Kai; Fan, Dongmei; Ding, Zhaotang; Su, Yanhua; Wang, Xiaochang

    2015-12-01

    The nitrogen source affects the growth of tea plants and regulates the accumulation of catechins in the leaves. In this report, we assessed the influences of NH4(+) and NO3(-) on plant growth, catechins accumulation and associated gene expression. Compared with the preferential nitrogen source NH4(+), when NO3(-) was supplied as the sole nitrogen source, tea plants showed similar symptoms with the nitrogen-free treatments and showed lower nitrogen, free amino acid accumulation, chlorophyll content and biomass gain, indicating NO3(-) was not efficiently used by these plants. However, the total shoot catechins content was significantly higher for NO3(-) treatments than that for NH4(+) treatment or combined NH4(+)+NO3(-) treatment, suggesting that, in addition to its influence on plant growth, the nitrogen form regulated the accumulation of catechins in tea. The expression of catechins biosynthesis-related genes was associated with the regulation of catechins accumulation and composition changes mediated by nitrogen form. PAL, CHS, CHI, and DFR genes exhibited higher expression levels in plants supplied with NO3(-), in which the transcript level of DFR in the shoots was significantly correlated with the catechins content. In the end, we identified a new function for the Cs-miR156, which was drastically induced through NH4(+). Moreover, a potential mechanism of the Cs-miR156 pathway in regulating catechins biosynthesis in tea plants has been suggested, with particular respect to nitrogen forms. Cs-miR156 might repress the expression of the target gene SPL to regulate the DFR gene, which plays a vital role in catechins biosynthesis. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  6. W-Band Polarimetric Scattering Features of a Tactical Ground Target Using a 1.56THz 3D Imaging Compact Range

    Science.gov (United States)

    2001-01-01

    differences in the amplitudes of scatterers (due primarily to elevation related phasing and aperture dependent pixel division) the PSMs of the TSAR images...on a T8OB with the TSAR data is shown in Figure 2. Figure 2a is an image made by projecting the 3D data onto a top view of the target. Figure 2b is...an TSAR data set taken at thesame angle. The TSAR measurements were made in a separate 1.56THz compact range where the model target is fully

  7. Numerical simulation of the electromagnetic decay of the nuclei {sup 152,154,156}Dy with self-consistent collective strength functions

    Energy Technology Data Exchange (ETDEWEB)

    Martin, V. [Analisis Numerico, Facultad de Informatica, Universidad Politecnica de Madrid, E-28660 Madrid (Spain); Egido, J.L. [Departamento de Fisica Teorica C-XI, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Khoo, T.L.; Lauritsen, T. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    1995-06-01

    The electromagnetic decay of the nuclei {sup 152,154,156}Dy is analyzed using microscopic Hartree-Fock calculations at finite temperature. The theoretical collective transition probabilities are implemented in numerical simulations to produce theoretical spectra. Thermal shape fluctuations are also taken into account. The inclusion of these correlation is crucial in order to understand the main features of the collective {ital E}2 spectra of these isotopes at different energies. The theoretical calculations suggest a shape change as responsible for the unusual features of the spectrum of the nucleus {sup 154}Dy at high energy.

  8. Induced Systemic Resistance against Botrytis cinerea by Bacillus cereus AR156 through a JA/ET- and NPR1-Dependent Signaling Pathway and Activates PAMP-Triggered Immunity in Arabidopsis

    OpenAIRE

    Nie, Pingping; Li, Xia; Wang, Shune; Guo, Jianhua; Zhao, Hongwei; Niu, Dongdong

    2017-01-01

    Induced resistance response is a potent and cost effective plant defense against pathogen attack. The effectiveness and underlying mechanisms of the suppressive ability by Bacillus cereus AR156 to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) in Arabidopsis has been investigated previously; however, the strength of induced systemic resistance (ISR) activity against Botrytis cinerea remains unknown. Here, we show that root-drench application of AR156 significantly reduces disease inciden...

  9. miR156-Targeted SBP-Box Transcription Factors Interact with DWARF53 to RegulateTEOSINTE BRANCHED1andBARREN STALK1Expression in Bread Wheat.

    Science.gov (United States)

    Liu, Jie; Cheng, Xiliu; Liu, Pan; Sun, Jiaqiang

    2017-07-01

    Genetic and environmental factors affect bread wheat ( Triticum aestivum ) plant architecture, which determines grain yield. In this study, we demonstrate that miR156 controls bread wheat plant architecture. We show that overexpression of tae-miR156 in bread wheat cultivar Kenong199 leads to increased tiller number and severe defects in spikelet formation, probably due to the tae-miR156-mediated repression of a group of SQUAMOSA PROMOTER BINDING PROTEIN-LIKE ( SPL ) genes. Furthermore, we found that the expression of two genes TEOSINTE BRANCHED1 ( TaTB1 ) and BARREN STALK1 ( TaBA1 ), whose orthologous genes in diverse plant species play conserved roles in regulating plant architecture, is markedly reduced in the tae-miR156-OE bread wheat plants. Significantly, we demonstrate that the strigolactone (SL) signaling repressor DWARF53 (TaD53), which physically associates with the transcriptional corepressor TOPLESS, can directly interact with the N-terminal domains of miR156-controlled TaSPL3/17. Most importantly, TaSPL3/17-mediated transcriptional activation of TaBA1 and TaTB1 can be largely repressed by TaD53 in the transient expression system. Our results reveal potential association between miR156-TaSPLs and SL signaling pathways during bread wheat tillering and spikelet development. © 2017 American Society of Plant Biologists. All Rights Reserved.

  10. Study on Expression Modes and Cleavage Role of miR156b/c/d and its Target Gene Vv-SPL9 During the Whole Growth Stage of Grapevine.

    Science.gov (United States)

    Wang, Baoju; Wang, Jian; Wang, Chen; Shen, Wenbiao; Jia, Haifeng; Zhu, Xudong; Li, Xiaopeng

    2016-01-01

    miR156 regulates the expression of its target SPL (PROMOTER BINDING-LIKE) genes during flower and fruit development, diverse developmental stage transitions, especially from vegetative to reproductive growth phases, by cleaving the target mRNA SPL of one plant-specific transcription factor. However, systematic reports on grapevine have yet to be presented. Here, the precise sequence of miR156 (vvi-miR156b/c/d) in grapevine "Takatsuma" was cloned with a previously cloned grapevine SPL (Vv-SPL9). Expression profiles in 18 grapevine tissues were identified through stem-loop RT-PCR. The interaction mode between vvi-miR156b/c/d and Vv-SPL9 was further validated by detecting the cleavage site and cleavage products of 3'- and 5'-ends via an integrated approach of 5'-RLM-RACE (RNA ligase-mediated 5'-rapid amplification of cDNA ends), 3'-PPM-RACE (poly(A) polymerase-mediated 3'-rapid amplification of cDNA ends), and qRT-PCR (real time reverse transcriptase-polymerase chain reaction). The variation in their cleavage roles in the whole growth stage of grapevine was also systematically investigated. Results showed that vvi-miR156b/c/d exhibited typical temporal-spatial-specific expression levels. The expression levels were higher in vegetative organs, such as leaf, than in reproductive organs, such as tendrils, flowers, and berries. A significant variation was observed during vegetative-to-reproductive transition. The expression patterns of Vv-SPL9 showed the opposite trends with those of vvi-miR156b. We confirmed that the cleavage site was at the 10th site of vvi-miR156b/c/d complementary to Vv-SPL9 in "Takatsuma" grapevine. We also identified the temporal-spatial variation of the cleavage products. This variation can indicate the regulatory function of miR156 on SPL in grapevines. Our findings provide further insights into the functions of vvi-miR156b/c/d and its target Vv-SPL9, and also help enrich our knowledge of small RNA-mediated regulation in grapevine. © The American

  11. Arg156 in the AP2-domain exhibits the highest binding activity among the 20 individuals to the GCC box in BnaERF-B3-hy15, a mutant ERF transcription factor from Brassica napus

    Directory of Open Access Journals (Sweden)

    Jing Zhuang

    2016-10-01

    Full Text Available To develop mutants of the ERF factor with more binding activities to the GCC box, we performed in vitro directed evolution by using DNA shuffling and screened mutants through yeast one-hybrid assay. Here, a series of mutants were obtained and used to reveal key amino acids that induce changes in the DNA binding activity of the BnaERF-B3 protein. With the BnaERF-B3-hy15 as the template, we produced 12 mutants which host individual mutation of potential key residues. We found that amino acid 156 is the key site, and the other 18 mutants host the 18 corresponding individual amino acid residues at site 156. Among the 20 individuals comprising WT (Gly156, Mu3 (Arg156, and 18 mutants with other 18 amino acid residues, Arg156 in the AP2-domain is the amino acid residue with the highest binding activity to the GCC box. The structure of the α-helix in the AP2-domain affects the binding activity. Other residues within AP2-domain modulated binding activity of ERF protein, suggesting that these positions are important for binding activity. Comparison of the mutant and wild-type transcription factors revealed the relationship of protein function and sequence modification. Our result provides a potential useful resource for understanding the trans-activation of ERF proteins.

  12. Arg156 in the AP2-Domain Exhibits the Highest Binding Activity among the 20 Individuals to the GCC Box in BnaERF-B3-hy15, a Mutant ERF Transcription Factor from Brassica napus.

    Science.gov (United States)

    Zhuang, Jing; Li, Meng-Yao; Wu, Bei; Liu, Yan-Jun; Xiong, Ai-Sheng

    2016-01-01

    To develop mutants of the ERF factor with more binding activities to the GCC box, we performed in vitro directed evolution by using DNA shuffling and screened mutants through yeast one-hybrid assay. Here, a series of mutants were obtained and used to reveal key amino acids that induce changes in the DNA binding activity of the BnaERF-B3 protein. With the BnaERF-B3-hy15 as the template, we produced 12 mutants which host individual mutation of potential key residues. We found that amino acid 156 is the key site, and the other 18 mutants host the 18 corresponding individual amino acid residues at site 156. Among the 20 individuals comprising WT (Gly156), Mu3 (Arg156), and 18 mutants with other 18 amino acid residues, Arg156 in the AP2-domain is the amino acid residue with the highest binding activity to the GCC box. The structure of the α-helix in the AP2-domain affects the binding activity. Other residues within AP2-domain modulated binding activity of ERF protein, suggesting that these positions are important for binding activity. Comparison of the mutant and wild-type transcription factors revealed the relationship of protein function and sequence modification. Our result provides a potential useful resource for understanding the trans-activation of ERF proteins.

  13. Suzaku Observations of Thermal and Non-Thermal X-Ray Emission from the Middle-Aged Supernova Remnant G156.2+5.7

    Science.gov (United States)

    Katsuda, Satoru; Petre, Robert; Hwang, Una; Yamaguchi, Hiroya; Mori, Koji; Tsunemi, Hiroshi

    2008-01-01

    We present results from X-ray analysis of a Galactic middle-aged supernova remnant (SNR) G156.2+5.7 which is bright and largely extended in X-ray wavelengths, showing a clear circular shape (radius approx.50'). Using the Suzaku satellite, we observed this SNR in three pointings; partially covering the northwestern (NW) rim, the eastern (E) rim, and the central portion of this SNR. In the NW rim and the central portion, we confirm that the X-ray spectra consist of soft and hard-tail emission, while in the E rim we find no significant hard-tail emission. The soft emission is well fitted by either a one-component or two-component non-equilibrium ionization (NEI) model. In the NW and E rims, a one-component (the swept-up interstellar medium) NEI model well represents the soft emission. On the other hand, in the central portion, a two-component (the interstellar medium and the metal-rich ejecta) NEI model fits the soft emission better than the one-component NEI model from a statistical point of view. The relative abundances in the ejecta component suggest that G156.2+5.7 is a remnant from a core-collapse SN explosion whose progenitor mass is less than 15 Solar Mass. The origin of the hard-tail emission detected in the NW rim and the central portion of the SNR is highly likely non-thermal synchrotron emission from relativistic electrons. In the NW rim, the relativistic electrons seems to be accelerated by a forward shock with a slow velocity of APPROX.500 km/sec.

  14. [Congenital sideroblastic anemia-a new family with identification of K156E mutation of ALAS2 gene and literature review].

    Science.gov (United States)

    Cui, Rui; Xu, Zefeng; Qin, Tiejun; Zhang, Yue; Xiao, Zhijian

    2014-02-01

    To raise awareness of molecular pathogenesis and treatment of congenital sideroblastic anemia (CSA). A complete blood count and iron metabolism were detected from the proband and other members of the family. Mutation analysis was performed on the complete coding regions of ALAS2 gene by common polymerase chain reaction (PCR) using genomic DNA as a template from members the family. ALAS2 mutations were detected by direct sequencing and mutation types were confirmed by sequencing followed by plasmid cloning. The proband male presented with microcytic hypochromic anemia (hemoglobin 84 g/L, mean corpuscular volume 64 fL, mean corpuscular hemoglobin 16.5 pg), and iron overload (serum iron 44.7 μmol/L, serum ferritin 3 123 μg/L and transferrin saturation 0.84). A mutation 466 A>G predicting a Lys156Glu amino acid change was identified in the proband and 3 females from the family. The proband was hemizygous for this mutation and presented with microcytic anemia and iron overload, while all 3 heterozygous females showed marginally increased red cell distribution width without any other symptoms. The proband treated with 300 mg of pyridoxine per day and iron chelation therapy with deferoxamine for one year had durable hematopoietic patients improvements, including increase in hemoglobin to 98 g/L and decrease in serum ferritin to 1 580 μg/L. This was a novel K156E substitution in ALAS2 gene identified in a 3-generation pedigree in China. Our findings emphasized the importance of gene based diagnosis of CSA, and CSA patient with ALAS2 mutation responded to pyridoxine treatment.

  15. In silico Prediction, in vitro Antibacterial Spectrum, and Physicochemical Properties of a Putative Bacteriocin Produced by Lactobacillus rhamnosus Strain L156.4

    Directory of Open Access Journals (Sweden)

    Letícia de C. Oliveira

    2017-05-01

    Full Text Available A bacteriocinogenic Lactobacillus rhamnosus L156.4 strain isolated from the feces of NIH mice was identified by 16S rRNA gene sequencing and MALDI-TOF mass spectrometry. The entire genome was sequenced using Illumina, annotated in the PGAAP, and RAST servers, and deposited. Conserved genes associated with bacteriocin synthesis were predicted using BAGEL3, leading to the identification of an open reading frame (ORF that shows homology with the L. rhamnosus GG (ATCC 53103 prebacteriocin gene. The encoded protein contains a conserved protein motif associated a structural gene of the Enterocin A superfamily. We found ORFs related to the prebacteriocin, immunity protein, ABC transporter proteins, and regulatory genes with 100% identity to those of L. rhamnosus HN001. In this study, we provide evidence of a putative bacteriocin produced by L. rhamnosus L156.4 that was further confirmed by in vitro assays. The antibacterial activity of the substances produced by this strain was evaluated using the deferred agar-spot and spot-on-the lawn assays, and a wide antimicrobial activity spectrum against human and foodborne pathogens was observed. The physicochemical characterization of the putative bacteriocin indicated that it was sensitive to proteolytic enzymes, heat stable and maintained its antibacterial activity in a pH ranging from 3 to 9. The activity against Lactobacillus fermentum, which was used as an indicator strain, was detected during bacterial logarithmic growth phase, and a positive correlation was confirmed between bacterial growth and production of the putative bacteriocin. After a partial purification from cell-free supernatant by salt precipitation, the putative bacteriocin migrated as a diffuse band of approximately 1.0–3.0 kDa by SDS-PAGE. Additional studies are being conducted to explore its use in the food industry for controlling bacterial growth and for probiotic applications.

  16. Photoluminescent study of Polycarbonate (PC) and Poly(9-vinylcarbazole) (PVK) doped films with europium complex; Estudo fotoluminescente de filmes de Policarbonato (PC) e Poli(9-vinilcarbazol) (PVK) dopados com complexo de europio

    Energy Technology Data Exchange (ETDEWEB)

    Forster, Pedro Lima

    2010-07-01

    Polymers doped with rare earth complexes are advantaged in film production for many applications in the luminescent field. In this study luminescent polymer obtained from polycarbonate (PC) and poly(9-vinylcarbazole) films doped with diaquatris(thenoyltrifluoroacetonate)europium(III) complex [Eu(tta){sub 3}(H{sub 2}0){sub 2}] were prepared and their calorimetric and luminescent properties in the solid state are reported. The thermal behavior was investigated by differential scanning calorimetry (OSC) and thermogravimetry analysis (TGA). Due of the addition of rare earth Eu(tta){sub 3}(H{sub 2}0){sub 2}] into PC and PVK matrices, changes were observed in the thermal behavior concerning the glass transition and thermal stability. Characteristic broadened narrow bands arising from the {sup 5}D{sub 0} -{yields} {sup 7}F{sub J} transitions (J = 0-4) of Eu{sup 3+} ion indicate the incorporation of the Eu{sup 3+} ions into those polymers. The luminescent films show enhancement emission intensity with an increase in the rare earth concentration in polymeric matrix accompanied by decrease in thermal stability. (author)

  17. Chemiluminescence Determination of Balofloxacin Based on Europium (III)-Sensitized KBrO{sub 3}-Na{sub 2}S{sub 2}O{sub 4} Reaction in Micellar Medium

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Fang; Qi, Yu; Xiong, Wei [Shihezi University, Shihezi (China)

    2012-01-15

    A novel chemiluminescence (CL) flow injection method for the determination of balofloxacin is described. The method is based on the weak CL signal arising from the reaction of KBrO{sub 3} with Na{sub 2}S{sub 2}O{sub 4} in acidic medium being significantly enhanced by balofloxacin in the presence of europium (III) ion and sodium dodecyl benzene sulfonate (SDBS). The experimental conditions that affected CL intensity were carefully optimized and the CL reaction mechanism was briefly discussed. Under the optimum conditions, the relative CL intensity was proportional to the concentration of balofloxacin in the range of 7.0 c 10{sup -11} to 3.0 x 10{sup -7} g mL{sup -1}. The detection limit was 2.7 x 10{sup -11} g mL{sup -1} and the relative standard deviation was 2.1% for 7.0 x 10{sup -10} g mL{sup -1} balofloxacin (n = 13). The proposed method was successfully applied to the determination of balofloxacin in pharmaceutical formulations and biological fluids.

  18. Synthesis, spectroscopic, DFT and optoelectronic studies of 2-benzylidene-3-hydroxy -1-(5,6-diphenyl-1,2,4-triazine-3-yl)hydrazine metal complexes

    Science.gov (United States)

    Taha, A.; Farag, A. A. M.; Adly, O. M. I.; Roushdy, N.; Shebl, Magdy; Ahmed, H. M.

    2017-07-01

    Metal complexes of Ni(II) and Cu(II) with a new Schiff base, 2-benzylidene-3-hydroxy -1-(5,6-diphenyl-1,2,4-triazine-3-yl)hydrazine (HBDHT) have been synthesized and characterized by elemental analysis and spectroscopic methods. The results adopt octahedral and square planar structures for Ni(II) and Cu(II) complexes, respectively with the formula, [Ni(BDHT)(NO3)(H2O)2)]·H2O and [Cu(BDHT)(H2O)](NO3)·H2O. The emission spectra arising from S1 state is assigned to π∗ →π and LUMO→HOMO transition character for investigated molecules. Structural parameters of the synthesized compounds were calculated on the basis of DFT level implemented in the Gaussian 09 program. The size of the prepared nano particles was obtained by scanning electron microscopy (SEM) and particle size analyzer. Analysis of the absorption coefficient near the fundamental absorption edge emphasizes two indirect allowed transitions n → π∗ and π → π∗ with energy gaps of 1.1 and 2.55 eV. The forward bias current of the prepared heterojunction shows diode-like behavior with appreciable rectification characteristics. The extracted heterojunction parameters show light dependence which supporting the achievability for the optical sensor in several optoelectronic applications.

  19. Erratum : Thesaurus for histopathological findings in publically available reports of repeated-dose oral toxicity studies in rats for 156 chemicals.

    Science.gov (United States)

    Nishikawa, Satoshi; Yamashita, Tatsuhiro; Imai, Toshio; Yoshida, Midori; Sakuratani, Yuki; Yamada, Jun; Maekawa, Akihiko; Hayashi, Makoto

    2010-08-01

    Because histopathological findings are often conclusive indicators of the toxicities of chemicals, standardization of nomenclature and construction of a thesaurus for histopathological findings are important for the comparative evaluation of histopathological data from repeated-dose toxicity studies (RTS). however, terms for histopathological findings have not been standardized and different technical terms are used to indicate almost the same things in RTS. The present study was conducted to construct and easy-to-use thesaurus for histopathological findings in order to facilitate hazard assessments of untested chemicals by the category approach using knowledge of the toxicity of analogue chemicals. We used reports of 28-day RTS, conducted on rats by gavage, which were posted on the websites of the National Institute of health Sciences (NIHS) and the National Institute of Technology and Evaluation (NITE). The histopathological data were from 156 reports on RTS conducted by 13 institutions in Japan. As a result of this study, major parts of the thesaurus were devoted to the findings in the liver, kidney, stomach, adrenal, thyroid and testis; the first three organs are known to be the main targets of chemicals. We also decided that findings such as swelling and enlargement of hepatocytes should be categorized as synonyms for terms meaning hypertrophy. Our thesaurus will be helpful in assessing or screening new untested chemical by the category approach using knowledge of the toxicities of analogues of the new chemical. The RTS database with this thesaurus will be made publically available in 2010.

  20. The 8-h tide in the mesosphere and lower thermosphere over Maui (20.75° N, 156.43° W

    Directory of Open Access Journals (Sweden)

    G. Jiang

    2009-05-01

    Full Text Available Wind data collected by the Maui meteor radar (20.75° N, 156.43° W are used to study the 8-h tide in the mesosphere and lower thermosphere (MLT region at a low-latitude station. The data set spans the time interval from 19 May 2002 to 24 May 2007. Our results show that the 8-h tide is a regular and distinct feature over Maui. The meridional component of this wave is significantly larger than the zonal component. The meridional component exhibits a semiannual variation in amplitude, with peaks near the equinoxes, whereas the variation of the zonal component does not show this seasonal characteristic. The strongest wave motions mostly occur in the height range of 92–96 km near spring equinox (March and at higher altitudes near autumn equinox (October. The vertical variations of 8-h tidal phase at Maui indicate an upward wave energy flux. The vertical wavelengths are ≥54 km in equinox months.

  1. 156 | P a g e

    African Journals Online (AJOL)

    Fr. Ikenga

    ONUEGBULAM: Right to Life under Legal and Jurisprudential Standards: Implications for Nigeria. RIGHT TO LIFE UNDER LEGAL AND JURISPRUDENTIAL .... In the traditional Igbo context, for example, life is the highest good, and “man” is the beauty of life; therefore, life is held sacred. Anything that will lead to loss of this ...

  2. Gold nanoparticle core-europium(iii) chelate fluorophore-doped silica shell hybrid nanocomposites for the lateral flow immunoassay of human thyroid stimulating hormone with a dual signal readout.

    Science.gov (United States)

    Preechakasedkit, Pattarachaya; Osada, Kota; Katayama, Yuta; Ruecha, Nipapan; Suzuki, Koji; Chailapakul, Orawon; Citterio, Daniel

    2018-01-21

    Hybrid nanocomposite particles composed of a gold core coated with a europium(iii)-chelate fluorophore-doped silica shell (AuNPs@SiO 2 -Eu 3+ ) have been synthesized and applied as antibody labels in lateral flow immunoassay (LFIA) devices for the determination of human thyroid stimulating hormone (hTSH). Labeling of monoclonal anti-hTSH antibodies with AuNPs@SiO 2 -Eu 3+ nanocomposites allows for both colorimetric and fluorometric observation of assay results on LFIA devices, relying on visible light absorption due to the localized surface plasmon resonance of the Au-core and the fluorescence emission of the Eu(iii)-chelate-modified shell under UV hand lamp irradiation (365 nm), respectively. The possibility for a dual signal readout provides an attractive alternative for LFIAs: instantaneous naked eye observation of the AuNP colorimetric signal as in conventional LFIAs for hypothyroidism detection, and more sensitive fluorescence detection to assess hyperthyroidism. The limits of detection (LOD) for naked eye observation of LFIA devices are 5 μIU mL -1 and 0.1 μIU mL -1 for the colorimetric and fluorimetric detection, respectively. Using the fluorescence detection scheme in combination with a smartphone and digital color analysis, a quantitative linear relationship between the red intensity and the logarithmic concentration of hTSH was observed (R 2 = 0.988) with an LOD of 0.02 μIU mL -1 . Finally, LFIA devices were effectively applied for detecting hTSH in spiked diluted human serum with recovery values between 100-116%.

  3. A europium- and terbium-coated magnetic nanocomposite as sorbent in dispersive solid phase extraction coupled with ultra-high performance liquid chromatography for antibiotic determination in meat samples.

    Science.gov (United States)

    Castillo-García, M L; Aguilar-Caballos, M P; Gómez-Hens, A

    2015-12-18

    A new magnetic dispersive solid-phase extraction approach based on Eu- and Tb-coated magnetic nanocomposites, combined with ultra-high performance liquid chromatography with fluorometric detection, is reported for the extraction and simultaneous determination of veterinary antibiotics. The method is aimed at monitoring of potential residues of three tetracyclines, namely oxytetracycline, tetracycline, chlortetracycline and three acidic quinolones, such as oxolinic acid, nalidixic acid and flumequine, chosen as model analytes, in animal muscle samples. The nanocomposites were obtained by synthesizing magnetic nanoparticles by a co-precipitation method and their coating with terbium and europium ions. The limits of detection obtained using standard solutions were: 1.0, 1.5, 3.8, 0.25, 0.7 and 1.2ngmL(-1), which corresponds to 3.3, 5.0, 12.7, 0.8, 2.3 and 4.0μgkg(-1) for oxytetracycline, tetracycline, chlortetracycline, oxolinic acid, nalidixic acid and flumequine, respectively, in meat samples. The precision values, obtained in the presence of the sample matrix, were in the ranges 0.12-2.0% and 2.6-15.4% for retention times and areas, respectively. The selectivity of the method was checked by assaying different veterinary drugs, finding that most of them did not interfere at the same concentration levels as that of analytes. A recovery study was performed in the presence of chicken and pork muscle samples, which provided values in the range of 61.5-102.6%. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Lupic nephropathy: a case control study in Medellín, Colombia Nefropatía lúpica: estudio de 156 casos

    Directory of Open Access Journals (Sweden)

    Fernando Zambrano

    1989-03-01

    Full Text Available

    By means of a case-control study we analyzed the cllnlcal histories of 297 patients with systemic erythematous lupus, that were seen at the out-patient section of the Rheumatology Service, Hospital Universitario San Vicente de Paúl, in Medellín, Colombia, between 1970 and 1987. Renal involvement was documented in 156 (52.5% cases while in 94 (31.6% there were alterations in the urinary sediment without clinical evidence of renal lesions. Nephropathy was the first evidence of disease in 14 patients (4.70¡0 of the total group; in 48 of those with nephropathy proteinuria was in the nephrotic range; acute renal insufficiency was found in 19 patients (6.4% while in 15 (5.0% there was chronic renal insufficiency. Seventy nine renal biopsies were performed; their histological classification was as follows: mesangial glomerulonephritis 7 (8.9%; focal proliferative glomerulonephritis 17 (21.5%; diffuse proliferative glomerulonephritis 38 (48.1% and membranous glomerulonephrltls 9 (11.1 %. The frequency of the following clinical manifestations was significantly higher in patients with nephropathy: Iivido reticularis, vasculitis, oral ulcers, arthritis, thrombophlebitis, psychosis, headache and depression.

    Por medio de un estudio de casos y controles se analizaron las historias de 297 pacientes con lupus eritematoso sistémico, atendidos en la consulta externa del Servicio de Reumatología del Hospital Universitario San Vicente de Paúl, en Medellín, Colombia, entre 1970 y 1987. Se documentó compromiso renal en 156 (52.5%. Hubo 94 que presentaron alteraciones en el sedimento urinario sin evidencia clínica de lesión renal. La nefropatía como primera manifestación de la enfermedad se encontró en 14 pacientes (4.7% del grupo total; en 48 de los que tenían neuropatía (30.8% se halló la proteinuria en

  5. Influence of Europium Doping on Various Electrical Properties of Low-Temperature Sintered 0.5Ba0.90Ca0.10TiO3-0.5BaTi0.88Zr0.12O3-0.1%CuO- xEu Lead-Free Ceramics

    Science.gov (United States)

    Tian, Yongshang; Li, Shuiyun; Sun, Shulin; Gong, Yansheng; Li, Tiantian; Yu, Yongshang; Jing, Qiangshan

    2018-01-01

    0.5Ba0.90Ca0.10TiO3-0.5BaTi0.88Zr0.12O3-0.1%CuO- xEu (BCT-BZT-Cu- xEu; x = 0-0.90%) lead-free ceramics were sintered at 1220°C with as-synthesized nanoparticles by a modified Pechini method. The structural characteristics and electrical properties of the ceramics that were influenced by varying europium-doping were investigated. All the ceramics featured high densification (relative density: ˜ 96%). X-ray powder diffraction results indicated the samples possessed pure orthorhombic phase. The maximum relative permittivity ( ɛ r, 10869) was found at x around 0.30%. Europium ions could dope on different substitution sites in the ABO3 lattice, which evidently influenced electrical properties with various volumes of oxygen vacancy. Moreover, the formation mechanisms of oxygen vacancy and defect electron complexes were stated. The piezoelectric properties were impacted by defect electron complexes, internal stress, ionic electronegativity, etc. The optimal electrical properties, i.e., d 33 = 384 pC/N, Q m = 92, and k p = 0.36, were detected at x = 0.45%.

  6. A 156 kyr smoothed history of the atmospheric greenhouse gases CO2, CH4, and N2O and their radiative forcing

    Science.gov (United States)

    Köhler, Peter; Nehrbass-Ahles, Christoph; Schmitt, Jochen; Stocker, Thomas F.; Fischer, Hubertus

    2017-06-01

    Continuous records of the atmospheric greenhouse gases (GHGs) CO2, CH4, and N2O are necessary input data for transient climate simulations, and their associated radiative forcing represents important components in analyses of climate sensitivity and feedbacks. Since the available data from ice cores are discontinuous and partly ambiguous, a well-documented decision process during data compilation followed by some interpolating post-processing is necessary to obtain those desired time series. Here, we document our best possible data compilation of published ice core records and recent measurements on firn air and atmospheric samples spanning the interval from the penultimate glacial maximum ( ˜ 156 kyr BP) to the beginning of the year 2016 CE. We use the most recent age scales for the ice core data and apply a smoothing spline method to translate the discrete and irregularly spaced data points into continuous time series. These splines are then used to compute the radiative forcing for each GHG using well-established, simple formulations. We compile only a Southern Hemisphere record of CH4 and discuss how much larger a Northern Hemisphere or global CH4 record might have been due to its interpolar difference. The uncertainties of the individual data points are considered in the spline procedure. Based on the given data resolution, time-dependent cutoff periods of the spline, defining the degree of smoothing, are prescribed, ranging from 5000 years for the less resolved older parts of the records to 4 years for the densely sampled recent years. The computed splines seamlessly describe the GHG evolution on orbital and millennial timescales for glacial and glacial-interglacial variations and on centennial and decadal timescales for anthropogenic times. Data connected with this paper, including raw data and final splines, are available at doi:10.1594/PANGAEA.871273.

  7. Multiple Genes Related to Muscle Identified through a Joint Analysis of a Two-stage Genome-wide Association Study for Racing Performance of 1,156 Thoroughbreds

    Directory of Open Access Journals (Sweden)

    Dong-Hyun Shin

    2015-06-01

    Full Text Available Thoroughbred, a relatively recent horse breed, is best known for its use in horse racing. Although myostatin (MSTN variants have been reported to be highly associated with horse racing performance, the trait is more likely to be polygenic in nature. The purpose of this study was to identify genetic variants strongly associated with racing performance by using estimated breeding value (EBV for race time as a phenotype. We conducted a two-stage genome-wide association study to search for genetic variants associated with the EBV. In the first stage of genome-wide association study, a relatively large number of markers (~54,000 single-nucleotide polymorphisms, SNPs were evaluated in a small number of samples (240 horses. In the second stage, a relatively small number of markers identified to have large effects (170 SNPs were evaluated in a much larger number of samples (1,156 horses. We also validated the SNPs related to MSTN known to have large effects on racing performance and found significant associations in the stage two analysis, but not in stage one. We identified 28 significant SNPs related to 17 genes. Among these, six genes have a function related to myogenesis and five genes are involved in muscle maintenance. To our knowledge, these genes are newly reported for the genetic association with racing performance of Thoroughbreds. It complements a recent horse genome-wide association studies of racing performance that identified other SNPs and genes as the most significant variants. These results will help to expand our knowledge of the polygenic nature of racing performance in Thoroughbreds.

  8. Multiple Genes Related to Muscle Identified through a Joint Analysis of a Two-stage Genome-wide Association Study for Racing Performance of 1,156 Thoroughbreds.

    Science.gov (United States)

    Shin, Dong-Hyun; Lee, Jin Woo; Park, Jong-Eun; Choi, Ik-Young; Oh, Hee-Seok; Kim, Hyeon Jeong; Kim, Heebal

    2015-06-01

    Thoroughbred, a relatively recent horse breed, is best known for its use in horse racing. Although myostatin (MSTN) variants have been reported to be highly associated with horse racing performance, the trait is more likely to be polygenic in nature. The purpose of this study was to identify genetic variants strongly associated with racing performance by using estimated breeding value (EBV) for race time as a phenotype. We conducted a two-stage genome-wide association study to search for genetic variants associated with the EBV. In the first stage of genome-wide association study, a relatively large number of markers (~54,000 single-nucleotide polymorphisms, SNPs) were evaluated in a small number of samples (240 horses). In the second stage, a relatively small number of markers identified to have large effects (170 SNPs) were evaluated in a much larger number of samples (1,156 horses). We also validated the SNPs related to MSTN known to have large effects on racing performance and found significant associations in the stage two analysis, but not in stage one. We identified 28 significant SNPs related to 17 genes. Among these, six genes have a function related to myogenesis and five genes are involved in muscle maintenance. To our knowledge, these genes are newly reported for the genetic association with racing performance of Thoroughbreds. It complements a recent horse genome-wide association studies of racing performance that identified other SNPs and genes as the most significant variants. These results will help to expand our knowledge of the polygenic nature of racing performance in Thoroughbreds.

  9. Clinical efficacy, radiographic progression, and safety through 156 weeks of therapy with subcutaneous golimumab in combination with methotrexate in Japanese patients with active rheumatoid arthritis despite prior methotrexate therapy: final results of the randomized GO-FORTH trial.

    Science.gov (United States)

    Tanaka, Yoshiya; Harigai, Masayoshi; Takeuchi, Tsutomu; Yamanaka, Hisashi; Ishiguro, Naoki; Yamamoto, Kazuhiko; Miyasaka, Nobuyuki; Koike, Takao; Baker, Daniel; Ishii, Yutaka; Yoshinari, Toru

    2016-07-01

    To evaluate the safety and efficacy of golimumab + methotrexate (MTX) in Japanese patients with active rheumatoid arthritis (RA). Japanese patients with active RA despite MTX were randomized to placebo + MTX (Group 1, n = 88), golimumab 50 mg + MTX (Group 2, n = 86), or golimumab 100 mg + MTX (Group 3, n = 87). Patients with <20% improvement in swollen/tender joint counts entered early escape at week 16. At week 24, all remaining placebo patients crossed over to golimumab 50 mg. Efficacy assessments included ACR20, DAS28-ESR, and HAQ-DI. Radiographic progression was assessed with the van der Heijde-modified Sharp (vdH-S) score. ACR20 response rates in Group 1, Group 2, and Group 3 were 67.9, 86.1, and 82.4%, respectively, at week 52 and were maintained through week 104 (87.1, 94.0, and 88.7%) and week 156 (97.1, 94.1, and 89.5%). Proportions of patients with good/moderate DAS28-ESR response or clinically meaningful improvement in HAQ-DI were also maintained through week 156. The majority of patients did not experience radiographic progression through week 156. Among 257 golimumab-treated patients, 251 (97.7%) had ≥1 AE; 54 (21.0%) had ≥1 serious AE through week 156. Infections were the most common type of AE. Response to golimumab + MTX was maintained over 3 years in Japanese patients with active RA despite MTX. Safety results were consistent with the known safety profile of golimumab.

  10. Signature inversion in πh{sub 11/2} x νi{sub 13/2} band of {sup 152}Eu and {sup 154,156}Tb

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Sushil [Akal University, Department of Physics, Talwandi Sabo (India); Maharishi Markandeshwar University, Department of Physics, Mullana (India); Singh, Sukhjeet [Akal University, Department of Physics, Talwandi Sabo (India); Sharma, Vandana; Sharma, J.K. [Maharishi Markandeshwar University, Department of Physics, Mullana (India)

    2017-04-15

    The phenomenon of signature inversion observed in the πh{sub 11/2} x νi{sub 13/2} band of {sup 152}Eu and {sup 156}Tb nuclides is revisited through the axially symmetric two quasiparticle plus rotor model approach. The magnitude of experimentally observed signature splitting and point of signature inversion, which could not be explicitly reproduced in the earlier calculations, is successfully reproduced in the present study. Some of the critical issues, such as violation of the well-established Gallagher Moszkowski (GM) rule for eight GM doublets appearing in the basis space of earlier calculations of {sup 152}Eu and {sup 156}Tb, are fixed and also the ambiguity regarding spin assignment to this band observed in {sup 156}Tb is resolved. These calculations are further extended to the same band (πh{sub 11/2} x νi{sub 13/2}) observed in {sup 154}Tb nuclide and signature inversion observed in this band is successfully reproduced. (orig.)

  11. Determination of the stability constants of lanthanum, praseodymium, europium, erbium and lutetium complexes with chloride ions; Determinacion de las constantes de estabilidad de los complejos de lantano, praseodimio, europio, erbio y lutecio con iones cloruro

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez R, E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2008-07-01

    The stability constants of La{sup 3+}, Pr{sup 3+}, Eu{sup 3+}, Er{sup 3+} and Lu{sup 3+} chloride complexes were determined in perchloric acid media using a liquid-liquid extraction method. The dinonyl napthalene sulfonic acid in n-heptane was used as extractant. The lanthanide (Ln) concentrations were measured by a radiochemical (Eu and Lu) and a spectrophotometric (La, Pr, and Er) methods. In the last method, xylenol orange was used for the determinations at ph 6. The stability constants of lanthanum, praseodymium, erbium and lutetium chloride complexes were determined in 2, 3 and 4 M ionic strength and europium in 1, 2 and 3 M, at 303 K. The fitting of experimental data to the equations for the calculation of the stability constants, was carry out considering both one chemical species (LnCl{sup 2+}) or two chemical species (LnCl{sup 2+} and LnCl{sub 2}{sup +}). The Specific Ion Interaction Theory was applied to the values of log {beta}{sup I}{sub Ln},{sub Cl} and the first stability constants at zero ionic strength were calculated by extrapolation. The same theory could not be applied to the log {beta}{sup I}{sub Ln},{sub 2Cl}, due to its low abundance and the values determined for the stability constants were similar. The distribution diagrams of the chemical species were obtained using the program MEDUSA and considering log {beta}{sup I}{sub Ln},{sub CI}, log {beta}{sup I}{sub Ln},{sub 2CI} values obtained in this work and the hydrolysis constants taken from the literature. The lanthanide chloride complexes are present in solution at specific conditions of ionic strength, concentration and in the absence of hydrolysis. The log {beta}{sup I}{sub Ln},{sub Cl} data were related to the charge density and the corresponding equations were obtained. These equations could be used to determine the stability constants along the lanthanide series. (Author)

  12. A first-in-human randomized, double-blind, placebo-controlled, single- and multiple-ascending oral dose study of novel Imidazolopiperazine KAF156 to assess its safety, tolerability, and pharmacokinetics in healthy adult volunteers.

    Science.gov (United States)

    Leong, F Joel; Zhao, Rong; Zeng, Shuqi; Magnusson, Baldur; Diagana, Thierry T; Pertel, Peter

    2014-11-01

    KAF156 belongs to a new class of antimalarial, the imidazolopiperazines, and is currently in clinical development for the treatment of uncomplicated malaria. This first-in-human, single- and multiple-ascending-dose study in 70 healthy male volunteers determined the maximum oral dose of KAF156 tolerated by healthy adults and derived pharmacokinetic data (including preliminary food effect) to enable dose calculations for malaria patients. KAF156 was studied in single-dose cohorts (10 to 1,200 mg, including one 400-mg food effect cohort (4 to 10 subjects/cohort), and in multiple-dose cohorts (60 to 600 mg once daily for 3 days; 8 subjects/cohort). The follow-up period was 6 to 14 days after the last dose. KAF156 was tolerated, with self-limited mild to moderate gastrointestinal and neurological adverse events. In treated subjects after single doses, headache (n = 4; 11.1%), diarrhea (n = 3; 8.3%), dizziness (n = 3; 8.3%), and abdominal pain (n = 2; 5.6%) were the most common adverse events. Headache (n = 4; 16.7%), nausea (n = 3; 12.5%), upper respiratory tract infection (n = 3; 12.5%), and dizziness (n = 2; 8.3%) were the most common adverse events following multiple doses. KAF156 time to maximum concentration (Tmax) was between 1.0 and 6.0 h. Both the area under the concentration-time curve (AUC) and maximum concentration (Cmax) increased more than dose-proportionally in both single- and multiple-ascending-dose cohorts (terminal half-life, 42.5 to 70.7 h). There was no significant accumulation over 3-day repeated administration. The extent of absorption was not significantly affected by food at a single dose of 400 mg, while mean Cmax decreased from 778 ng/ml to 627 ng/ml and Tmax was delayed from a median of 3.0 h under fasting conditions to 6.0 h under fed conditions. Renal elimination is a minor route. Copyright © 2014 Leong et al.

  13. Electrochemistry of Europium(III) Chloride in 3 LiCl – NaCl, 3 LiCl – 2 KCl, LiCl – RbCl, and 3 LiCl – 2 CsCl Eutectics at Various Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Schroll, Cynthia A.; Chatterjee, Sayandev; Levitskaia, Tatiana G.; Heineman, William R.; Bryan, Samuel A.

    2017-01-01

    Here we report the effect of changing the eutectic melt composition on the electrochemical properties of europium(III) chloride under pyroprocessing conditions. The number of electrons transferred, redox potentials and diffusion coefficients were determined using various electrochemical and spectroelectrochemical techniques in four different eutectic mixtures (3 LiCl - NaCl, 3 LiCl - 2 KCl, 3 LiCl - RbCl, and 3 LiCl - 2 CsCl) while varying the temperature of the melt. It was determined that Eu3+ undergoes a one electron reduction to Eu2+ in each melt at all temperatures evaluated. Within all the melts a positive shift in the redox potential as well as an increase in the diffusion coefficient for Eu3+ was observed as the temperature increased. Also observed was a positive shift in the redox potential and increase in the diffusion coefficient for Eu3+ as the weighted average of the cationic radii for the melt decreased.

  14. Synthesis and characterization of Bi{sub 1.56}Sb{sub 1.48}Co{sub 0.96}O{sub 7} pyrochlore sun-light-responsive photocatalyst

    Energy Technology Data Exchange (ETDEWEB)

    Naceur, Benhadria, E-mail: nacer1974@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, Department of Materials Engineering, University of Science and Technology of Oran (USTO M.B), BP 1505, El M’naouar, 31000 Oran (Algeria); Abdelkader, Elaziouti, E-mail: elaziouti_a@yahoo.com [Laboratory of Inorganic Materials Chemistry and Application, Department of Materials Engineering, University of Science and Technology of Oran (USTO M.B), BP 1505, El M’naouar, 31000 Oran (Algeria); Dr Moulay Tahar University, Saida (Algeria); Nadjia, Laouedj, E-mail: nlaouedj@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, Department of Materials Engineering, University of Science and Technology of Oran (USTO M.B), BP 1505, El M’naouar, 31000 Oran (Algeria); Dr Moulay Tahar University, Saida (Algeria); Sellami, Mayouf, E-mail: Mourad7dz@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, Department of Materials Engineering, University of Science and Technology of Oran (USTO M.B), BP 1505, El M’naouar, 31000 Oran (Algeria); Noureddine, Bettahar, E-mail: nbettahar2001@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, Department of Materials Engineering, University of Science and Technology of Oran (USTO M.B), BP 1505, El M’naouar, 31000 Oran (Algeria)

    2016-02-15

    Graphical abstract: Heterogeneous photo Fenton process with dye sensitized mechanism of RhB by Bi{sub 1.56}Sb{sub 1.48}Co{sub 0.96}O{sub 7} compound. - Highlights: • Bi{sub 1.56}Sb{sub 1.48}Co{sub 0.96}O{sub 7} (BSCO) catalyst was synthesized by improved solid state reaction method. • BSCO/H{sub 2}O{sub 2}/UVA and BSCO/H{sub 2}O{sub 2}/SL catalyst systems exhibit excellent photocatalytic activities for rhodamine B. • The photocatalytic degradation was preceded via heterogeneous photo Fenton mechanism process. • ·OH radicals are the main reactive species for the degradation of RhB. - Abstract: Novel nanostructure pyrochlore Bi{sub 1.56}Sb{sub 1.48}Co{sub 0.96}O{sub 7} was successfully synthesized via solid state reaction method in air. The as-synthesized photocatalyst was characterized by X-ray diffraction, Scanning electron microscopy and UV–vis diffuse reflectance spectroscopy techniques. The results showed that the BSCO was crystallized with the pyrochlore-type structure, cubic crystal system and space group Fd3m. The average particle size and band gap for BSCO were D = 76.29 nm and E{sub g} = 1.50 eV respectively. Under the optimum conditions for discoloration of the dye: initial concentration of 20 mg L{sup −1} RhB, pH 7, 25 °C, 0.5 mL H{sub 2}O{sub 2} and BSCO/dye mass ration of 1 g L{sup −1}, 97.77 and 90.16% of RhB were removed with BSCO/H{sub 2}O{sub 2} photocatalytic system within 60 min of irradiation time under UVA- and SL irradiations respectively. Pseudo-second-order kinetic model gave the best fit, with highest correlation coefficients (R{sup 2} ≥ 0.99). On the base of these results, the mechanism of the enhancement of the discoloration efficiency was discussed. .

  15. Photoresponse and DFT studies of new synthesized 2-benzylidene-3-hydroxy -1-(5,6-diphenyl-1,2,4-triazine-3-yl)hydrazine and optical sensor application

    Science.gov (United States)

    Taha, A.; Farag, A. A. M.; Adly, O. M. I.; Roushdy, N.; Shebl, Magdy; Ahmed, H. M.

    2017-08-01

    A newly Schiff base,2-benzylidene-3-hydroxy-1-(5,6-diphenyl-1,2,4-triazine-3-yl)hydrazine] (HBDHT) was synthesized and characterized on the basis of micro-analytical and spectroscopic studies. Basic parameters of the combined compound HBDHT were ascertained on the premise of DFT level actualized on Gaussian 09. Thin films of HBDHT were successfully prepared by spin coating technique and confirmed by atomic force microscopy (AFM). The optical attributes of the studied films were considered utilizing spectrophotometric estimations in a wide spectral range of 200-2500 nm. Some important optical parameters such as extinction index, refractive index, dispersion energy, oscillator energy and high-frequency dielectric constant were extracted. Analysis of the absorption coefficient near the fundamental absorption edge confirms an indirectly allowed transition with an energy gap of 1.7eV. The refractive index dispersion was estimated on basis of single oscillator model expressed by Wemple-Didomenico. Current-voltage (I-V) characteristics were studied in dark and under illumination of 100 mW/cm2 to clarify the sensitivity to light. Moreover, the photo-transient properties were also investigated to confirm that the prepared heterojunction based HBDHT can be operated as a photodiode.

  16. Personalized mapping of the deep brain with a white matter attenuated inversion recovery (WAIR) sequence at 1.5-tesla: Experience based on a series of 156 patients.

    Science.gov (United States)

    Zerroug, A; Gabrillargues, J; Coll, G; Vassal, F; Jean, B; Chabert, E; Claise, B; Khalil, T; Sakka, L; Feschet, F; Durif, F; Boyer, L; Coste, J; Lemaire, J-J

    2016-08-01

    Deep brain mapping has been proposed for direct targeting in stereotactic functional surgery, aiming to personalize electrode implantation according to individual MRI anatomy without atlas or statistical template. We report our clinical experience of direct targeting in a series of 156 patients operated on using a dedicated Inversion Recovery Turbo Spin Echo sequence at 1.5-tesla, called White Matter Attenuated Inversion Recovery (WAIR). After manual contouring of all pertinent structures and 3D planning of trajectories, 312 DBS electrodes were implanted. Detailed anatomy of close neighbouring structures, whether gray nuclei or white matter regions, was identified during each planning procedure. We gathered the experience of these 312 deep brain mappings and elaborated consistent procedures of anatomical MRI mapping for pallidal, subthalamic and ventral thalamic regions. We studied the number of times the central track anatomically optimized was selected for implantation of definitive electrodes. WAIR sequence provided high-quality images of most common functional targets, successfully used for pure direct stereotactic targeting: the central track corresponding to the optimized primary anatomical trajectory was chosen for implantation of definitive electrodes in 90.38%. WAIR sequence is anatomically reliable, enabling precise deep brain mapping and direct stereotactic targeting under routine clinical conditions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Photoelectric stimulation of defined ear points (Smokex-Pro method) as an aid for smoking cessation: a prospective observational 2-year study with 156 smokers in a primary care setting.

    Science.gov (United States)

    Breivogel, B; Vuthaj, B; Krumm, B; Hummel, J; Cornell, D; Diehl, A

    2011-01-01

    Smokex-Pro is a smoking cessation method using a protocol of a standardized consultation and computer-assisted photoelectric stimulation of defined regions in the ear and face. We prospectively enrolled 156 consecutive adult smokers (81 males, 75 females; mean age 43.8 years; body mass index 25.5; daily cigarettes 24.7; Fagerström Test for Nicotine Dependence 5; 30 smoking years). The primary end point was the self-reported continuous abstinence rate. Participants completed on average only 32% of recommended visits. A total of 76.7% stopped smoking for more than 7 days. Moreover, 53.4% remained free of smoking for more than 90 days. Long-term abstinence rates were 49.3% (1 year) and 47.95% (2 years). Treatment-related side effects were observed in 24.5% of participants. Side effects were mild and resolved within hours. The Smokex-Pro method appears to be an effective aid for smoking cessation. The treatment was well tolerated and showed only mild and temporary side effects. The average cost of treatment is typically less than EUR 90; the total treatment time is typically 60-90 min. These factors make it an attractive alternative compared to traditional smoking cessation methods. Controlled clinical trials will be needed to confirm the results of this study and refine the treatment for maximum efficacy. Copyright © 2011 S. Karger AG, Basel.

  18. 40 CFR 93.156 - Public participation.

    Science.gov (United States)

    2010-07-01

    ... analytical methods and conclusions relied upon in making the applicability analysis and draft conformity... placing a notice by prominent advertisement in a daily newspaper of general circulation in the area....158 for a Federal action by placing a notice by prominent advertisement in a daily newspaper of...

  19. 18 CFR 156.5 - Exhibits.

    Science.gov (United States)

    2010-04-01

    ... local authorizations. (i) A copy of any certificate of public convenience and necessity or similar..., showing towns and communities to be served, and (b) gas producing and storage filed, or other sources of.... (8) Exhibit G-II—Flow diagram data. Exhibits G and G-I shall be accompanied by a statement of...

  20. Reference: 156 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available dopsis thaliana . We demonstrate that loss of DEL1 function resulted in increased ploidy levels, whereas ectopic...nics. DEL1 inhibited the endoreduplication phenotype, but not the ectopic cell divisions that resulted from

  1. 156 ORIGINAL ARTICLE PREVALENCE OF BACTERIAL ...

    African Journals Online (AJOL)

    Dr Oboro VO

    Almost half of patients with trichomoniasis were found to have bacterial vaginosis (P<0.05). The demonstration Clue cells in wet mount was found in significantly higher numbers (90.5%) in women with bacterial vaginosis (P<0.001, positive predictive value 90.4%) while low sensitivity and positive predictive value were seen ...

  2. Publications | Page 156 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Presented posters [appendix 10 of the joint technical final report (October 2010 - March 2013)] (restricted access). Posters for integrated information campaigns targeting various audiences of farmers, women farmers and entrepreneurs, engineers, agronomists, nutritionists, food producers and chefs, delineate the uses and ...

  3. BDML Metadata: 156 [SSBD[Archive

    Lifescience Database Archive (English)

    Full Text Available Ce_KK_P002 BDML file for quantitative information about nuclear division dynamics o...f R08D7.1(RNAi) embryo quantitative information about nuclear division dynamics in R08D7.1(RNAi) embryo C. e...legans nuclear division dynamics R08D7.1(gPCR)080514_03 Measurement Kyoda, K., Furukawa, M., Arai, R., Onami

  4. 156 ORIGINAL ARTICLE PREVALENCE OF BACTERIAL ...

    African Journals Online (AJOL)

    Dr Oboro VO

    4. van De Wijgert JH, Mason PR,. Gwanzura L, Mbizvo MT, Chirenje ZM,. Iliff V, et al. Intravaginal practices, vaginal flora disturbances, and acquisition of sexually transmitted diseases in Zimbabwean women. J Infect. Dis 2000;181(2):587-94. 5. Hillier SL. Diagnostic microbiology of bacterial vaginosis. Am J Obstet Gynecol.

  5. 156-IJBCS-Article-Ir T Houehanou

    African Journals Online (AJOL)

    RHUMSIKI

    Le climat est tropical sec de type soudano-sahélien ou Nord-soudanien caractérisé par une saison ... a été semi informelle et a porté sur un échantillon de quinze (15) éleveurs Peuls. (tous agro pastoraux) par ..... zone semi-aride des savanes d'Afrique centrale. Agricultures, 13(4): 331-340. Piot J, 1980. Les méthodes de ...

  6. Publications | Page 156 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    In order to do so, the paper builds models that explain the evolution of productivity of knowledge intensive based services, including the effects of... Adapting to Climate Change in Urbanizing Watersheds (ACCUWa) : situation in Arkavathy basin (restricted access) · On the development of climate data visualization tool for ...

  7. Environmental Radiation Data (ERD) Journal Report 156

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of October - December 2013. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.

  8. 40 CFR 82.156 - Required practices.

    Science.gov (United States)

    2010-07-01

    ... of heat to atmospheric pressure; or (C) For the purposes of oil changes, be evacuated or pressurized to a pressure no higher than 5 psig, before it is opened; or drain the oil into a system receiver to... with the manufacturer's directions unless such directions conflict with the requirements of this...

  9. 34 CFR 300.156 - Personnel qualifications.

    Science.gov (United States)

    2010-07-01

    ... in their discipline or profession— (i) Meet the requirements of paragraph (b)(1) of this section; and... with the SEA as provided for under this part. (Approved by the Office of Management and Budget under...

  10. 40 CFR 156.10 - Labeling requirements.

    Science.gov (United States)

    2010-07-01

    ... the environment. (h) (i) Directions for Use—(1) General requirements—(i) Adequacy and clarity of... to protect the public from fraud and from personal injury and to prevent unreasonable adverse effects...

  11. 21 CFR 156.3 - Definitions.

    Science.gov (United States)

    2010-04-01

    ... prescribed in “Official Methods of Analysis of the Association of Official Analytical Chemists,” 13th Ed... percent sodium chloride, by the method prescribed in “Official Methods of Analysis of the Association of Official Analytical Chemists,” 13th Ed., 1980, sections 32.025 to 32.030, under the heading “Method III...

  12. Effect of oxygen partial pressure and temperature on NTC characteristics of Mn{sub 1.56}Co{sub 0.96}Ni{sub 0.48}O{sub 4} thin films grown on SrTiO{sub 3} (1 0 0) by laser MBE

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yahong [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry of CAS, Urumqi 830011 (China); Key Laboratory of Oil and Gas Fine Chemicals, Ministry of Education and Xinjiang Uyghur Autonomous Region, Xinjiang University, Urumqi 830046 (China); Ji, Guang [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry of CAS, Urumqi 830011 (China); Bu, Haijun [Key Laboratory of Nanodevices and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Science, Suzhou 215123 (China); Kong, Wenwen; Gao, Bo; Yao, Jincheng [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry of CAS, Urumqi 830011 (China); Chang, Aimin, E-mail: changam@ms.xjb.ac.cn [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry of CAS, Urumqi 830011 (China); Jiang, Chunping, E-mail: cpjiang2008@sinano.ac.cn [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry of CAS, Urumqi 830011 (China); Key Laboratory of Nanodevices and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Science, Suzhou 215123 (China)

    2014-10-25

    Highlights: • Single (1 0 0)-oriented MCNO thin films were deposited on MgO substrate. • NTC thin film was prepared through LMBE technique for the first time. • The prepared thin films achieved epitaxial growth. • The prepared thin films achieved epitaxial growth. - Abstract: Single (1 0 0)-oriented Mn{sub 1.56}Co{sub 0.96}Ni{sub 0.48}O{sub 4} thin films were achieved on SrTiO{sub 3} (1 0 0) substrate using laser molecular beam epitaxy technique. The effects of growth temperature and oxygen partial pressure on crystal quality and negative temperature coefficient characteristics were studied by XRD, RHEED, AFM, SEM, resistance–temperature measurements and impedance spectrum. The results showed that the growth direction (4 0 0) of epitaxial Mn{sub 1.56}Co{sub 0.96}Ni{sub 0.48}O{sub 4} thin films was parallel to SrTiO{sub 3} (1 0 0) substrate and the best NTC characteristic with B value of about 3000 K was found in the Mn{sub 1.56}Co{sub 0.96}Ni{sub 0.48}O{sub 4} thin films grown at 500 °C with Po{sub 2} = 5 × 10{sup −3} Pa for 3 h. Such thin films are desirable for a wide range of practical applications in the NTC thermistors.

  13. Progress on the europium neutron capture study using DANCE

    Energy Technology Data Exchange (ETDEWEB)

    Agvaanluvsan, U. [Lawrence Livermore National Laboratory, 7000 East Avenue, P.O. Box 808, L-414, Livermore, CA 94551 (United States)]. E-mail: agvaanluvsan1@llnl.gov; Becker, J.A. [Lawrence Livermore National Laboratory, 7000 East Avenue, P.O. Box 808, L-414, Livermore, CA 94551 (United States); Macri, R.A. [Lawrence Livermore National Laboratory, 7000 East Avenue, P.O. Box 808, L-414, Livermore, CA 94551 (United States); Parker, W. [Lawrence Livermore National Laboratory, 7000 East Avenue, P.O. Box 808, L-414, Livermore, CA 94551 (United States); Wilk, P. [Lawrence Livermore National Laboratory, 7000 East Avenue, P.O. Box 808, L-414, Livermore, CA 94551 (United States); Wu, C.Y. [Lawrence Livermore National Laboratory, 7000 East Avenue, P.O. Box 808, L-414, Livermore, CA 94551 (United States); Bredeweg, T.A.; Esch, E.; Haight, R.C.; O' Donnell, J.M.; Reifarth, R.; Rundberg, R.S.; Schwantes, J.M.; Ullmann, J.L.; Vieira, D.J.; Wilhelmy, J.B.; Wouters, J.M. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Mitchell, G.E.; Sheets, S. [North Carolina State University, Raleigh, NC 27695 (United States)]|[Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Becvar, F.; Krticka, M. [Charles University in Prague, CZ 180 00 Prague 8 (Czech Republic)

    2007-08-15

    The accurate measurement of neutron capture cross sections of the Eu isotopes is important for many reasons including nuclear astrophysics and nuclear diagnostics. Neutron capture excitation functions of {sup 151,153}Eu targets were measured recently using a 4{pi} {gamma}-ray calorimeter array DANCE located at the Los Alamos Neutron Science Center for E {sub n} = 0.1-100 keV. The progress on the data analysis efforts is given in the present paper. The {gamma}-ray multiplicity distributions for the Eu targets and Be backing are significantly different. The {gamma}-ray multiplicity distribution is found to be the same for different neutron energies for both {sup 151}Eu and {sup 153}Eu. The statistical simulation to model the {gamma}-ray decay cascade is summarized.

  14. Progress on the Europium Neutron-Capture Study using DANCE

    Energy Technology Data Exchange (ETDEWEB)

    Agvaanluvsan, U; Becker, J A; Macri, R A; Parker, W; Wilk, P; Wu, C Y; Bredeweg, T A; Esch, E; Haight, R C; O' Donnell, J M; Reifarth, R; Rundberg, R S; Schwantes, J M; Ullmann, J L; Vieira, D J; Wilhelmy, J B; Wouters, J M; Mitchell, G E; Sheets, S A; Becvar, F; Krticka, M

    2006-09-05

    The accurate measurement of neutron-capture cross sections of the Eu isotopes is important for many reasons including nuclear astrophysics and nuclear diagnostics. Neutron capture excitation functions of {sup 151,153}Eu targets were measured recently using a 4{pi} {gamma}-ray calorimeter array DANCE located at the Los Alamos Neutron Science Center for E{sub n} = 0.1-100 keV. The progress on the data analysis efforts is given in the present paper. The {gamma}-ray multiplicity distributions for the Eu targets and Be backing are significantly different. The {gamma}-ray multiplicity distribution is found to be the same for different neutron energies for both {sup 151}Eu and {sup 153}Eu. The statistical simulation to model the {gamma}-ray decay cascade is summarized.

  15. Functionalization of sol-gel zirconia composites with europium complexes

    Energy Technology Data Exchange (ETDEWEB)

    Danchova, Nina; Gutzov, Stoyan [Sofia Univ. ' St Kliment Ohridski' (Bulgaria). Dept. of Physical Chemistry

    2014-02-15

    Different sol-gel strategies based on functionalization of ZrO{sub 2}:Eu microparticles with 1,10-phenanthroline (phen) and incorporation of colloidal Eu(phen){sub 2}(NO{sub 3}){sub 3} into zirconia have been used to obtain hybrid sol-gel composites with controlled optical properties. The process leads to materials with quantum yields of about 48 % monitoring the 615 nm emission line at 350 nm excitation. Excitation/luminescence spectroscopy, diffuse reflectance spectroscopy and X-ray diffraction have been used to characterize the hybrid zirconia composites. (orig.)

  16. Interaction of europium and curium with alpha-amylase

    Energy Technology Data Exchange (ETDEWEB)

    Barkleit, Astrid [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Chemistry of the F-Elements; Heller, Anne [Technische Univ. Dresden (Germany). Inst. for Zoology, Molecular Cell Physiology and Endocrinology; Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Biogeochemistry

    2016-07-01

    Time-resolved laser-induced fluorescence spectroscopy (TRLFS) revealed that Eu(III) and Cm(III) form two dominant species with the protein α-amylase (Amy): one with the coordination of a single carboxylate group of the protein and the other with three coordinating carboxylate groups.

  17. Synthesis, characterization, and properties of reduced europium molybdates and tungstates

    Science.gov (United States)

    Abeysinghe, Dileka; Gerke, Birgit; Morrison, Gregory; Hsieh, Chun H.; Smith, Mark D.; Pöttgen, Rainer; Makris, Thomas M.; zur Loye, Hans-Conrad

    2015-09-01

    Single crystals of K0.094Eu0.906MoO4, K0.097Eu0.903WO4, EuWO4, and EuMoO4 were grown from molten chloride fluxes contained in vacuum-sealed fused silica and structurally characterized via single crystal X-ray diffraction. The in situ reduction of Eu3+ to Eu2+ was carried out using Mo, W, and Zn as metal reducing agents. All four compounds crystallize in the tetragonal space group of I41/a and adopt the scheelite (CaWO4) structure type. The magnetic susceptibility of the reported compounds shows paramagnetic behavior down to 2 K. 151Eu Mössbauer spectroscopy was used to analyze the relative Eu2+ and Eu3+ content of the samples. All the compounds were further characterized by EPR, and UV-vis spectroscopy.

  18. Electrical and magnetic transport in Strontium doped Europium Ferrimanganites

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Latif, I.A. [Physics Department, College of Science & Arts, Najran University, P. O. 1988, Najran (Saudi Arabia); Reactor Physics Department, NRC, Atomic Energy Authority, Abou Zabaal P.O. 13759, Cairo (Egypt); Ahmed, Mahrous R. [Physics Department, Faculty of Science, Sohag University, Sohag 82524 (Egypt); Physics Department, Aljamoum University College, Um-Elqura University, Makka (Saudi Arabia); Al-Omari, I.A.; Sellai, A. [Physics Department, Faculty of Science, Soltan Qaboos University, P.O. Box 36, PC 123, Muscatt (Oman)

    2016-12-15

    Eu{sub 0.65}Sr{sub 0.35}Fe{sub x}Mn{sub 1−x}O{sub 3} (x=0.1, 0.3 and 0.5) has been prepared using a standard solid state reaction method. The under-investigation compounds is found to crystallize in a single-phase orthorhombic structure in the P{sub bnm} space group (62). The adiabatic polaron electronic transfer was obtained for all samples and the activation energy of x=0.1 sample is equal to 1.013 meV and slightly increase at x=0.3 (1.289 meV) while is doubled for x=0.5 to be 2.1065 meV. The magnetization–temperature dependence measurements of Eu{sub 0.65}Sr{sub 0.35}Fe{sub x}Mn{sub 1−x}O{sub 3} show the ferromagnetic ordering at low iron concentration x=0.1 and when iron concentration increase to x=0.5 the noncollinear magnetic ordering (the canted antiferromagnetic) is obtained. The magnetic phase transition (paramagnetic-ferromagnetic transition) in the Eu{sub 0.65}Sr{sub 0.35}Fe{sub 0.1}Mn{sub 0.9}O{sub 3} is observed at T{sub c} of 150 K. For Eu{sub 0.65}Sr{sub 0.35}Fe{sub 0.5}Mn{sub 0.5}O{sub 3} the multi-magnetic phase transition is observed at T{sub c} of 200K and T{sub N} of 430 K. The resistivity at low temperature is measured. Theoretical Calculations using Monte Carlo code have been done. The magnetization as function of temperature has been calculated using Monte Carlo simulations for Eu{sub 0.65}Sr{sub 0.35}Fe{sub x}Mn{sub 1−x}O{sub 3} (x=0.0, 0.1, 0,2, 0.3, 0.4 and 0.5). Ising model is a suitable model to study the magnetization for our compounds. The internal energy for x=0 is the highest value compared with the other x values which have nearly a ground state value equal to 2.7 J. - Highlights: • The distortion parameter in the crystal structure of Eu{sub 0.65}Sr{sub 0.35}Fe{sub x}Mn{sub 1−x}O{sub 3} increase with increasing concentration of iron and affected both electrical and magnetic transport. • The density of electrons over the unit cell decrease with increasing the iron concentration and thus give rise to the decrease in electrical conductivity and the change of the magnetic ordering. • The transition from thermal activation mechanism at temperature higher than room temperature into adiabatic polaron mechanism at temperature lower than room temperature in all samples. • The transition from the soft FM ordering at low iron concentration x=0.1 into the harder canted FM ordering with x>0.3. • The internal energy calculation showed the highest value of x=0, compared with the other x values, which have nearly a ground state value equal to 2.7 J.

  19. Synthesis and characterization of europium doped LiF phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Villalobos, M. L.; Vallejo, M. A.; Sosa A, M. [Universidad de Guanajuato, Division de Ciencias e Ingenierias, Loma del Bosque No. 103, Lomas del Campestre, 37150 Leon, Guanajuato (Mexico); Diaz T, L. A., E-mail: villaloboscm2010@licifug.ugto.mx [Centro de Investigaciones en Optica, A. C., Loma del Bosque No. 115, Lomas del Campestre, 37150 Leon, Guanajuato (Mexico)

    2015-10-15

    LiF with different dopants has been one of the most investigated materials to use as thermoluminescent dosimeter. In this paper, we present the preparation method, the characterization and the thermoluminescent response of Eu doped LiF irradiated with X-rays. Pure and Eu doped LiF samples with different dopant concentration (0, 0.25, 0.5, 0.75 and 1 % mol) were synthesized using the precipitation method. The samples were structurally characterized by X-ray diffraction (XRD), the diffraction patterns showed a main cubic crystalline structure and a secondary hexagonal structure. The photoluminescence spectrum exhibited four well defined peaks characteristic of the Eu{sup 3+} ion. Thermoluminescent (Tl) glow curves of x-ray irradiated samples showed a well-defined single peak around 200 degrees C, except for the pure and 0.25% Eu doped samples. (Author)

  20. Effect of pressure on the phonon properties of europium ...

    Indian Academy of Sciences (India)

    Unknown

    phonon density of states and compared them with the first order Raman scattering results. The calculation of ... raman et al 1974). The structural phase transition pre- ssures for EuO, EuS, EuSe and EuTe are 30–40 GPa,. 22 GPa, 15 GPa and 10 GPa, respectively. ... †Paper presented at the 5th IUMRS ICA98, October 1998,.

  1. High pressure annealing of Europium implanted GaN

    KAUST Repository

    Lorenz, K.

    2012-02-09

    GaN epilayers were implanted with Eu to fluences of 1×10^13 Eu/cm2 and 1×10^15 Eu/cm2. Post-implant thermal annealing was performed in ultra-high nitrogen pressures at temperatures up to 1450 ºC. For the lower fluence effective structural recovery of the crystal was observed for annealing at 1000 ºC while optical activation could be further improved at higher annealing temperatures. The higher fluence samples also reveal good optical activation; however, some residual implantation damage remains even for annealing at 1450 ºC which leads to a reduced incorporation of Eu on substitutional sites, a broadening of the Eu luminescence lines and to a strongly reduced fraction of optically active Eu ions. Possibilities for further optimization of implantation and annealing conditions are discussed.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  2. Hyperfine interactions at europium sites in oxide glasses

    Science.gov (United States)

    Concas, G.; Congiu, F.; Muntoni, C.; Bettinelli, M.; Speghini, A.

    1996-03-01

    The shape of the γ resonance absorption peak of the Eu3+ ion in a disordered structure was investigated in some phosphate, borate, and silicate glasses by using 151Eu Mössbauer spectroscopy. The quality of the fits was tested by using the Durbin-Watson d statistics. The observed full width at half maximum of the peak was resolved in a contribution of the broadening and a contribution of the quadrupole splitting, due to the distortion of the Eu site compared to a cubic symmetry. The Eu-O bond was found to have a covalent admixture with 6s character. The axial component of the electric-field gradient at the Eu site was found to be correlated with the optical basicity of the glass.

  3. Interaction of europium and curium with alpha-amylase.

    Science.gov (United States)

    Barkleit, Astrid; Heller, Anne; Ikeda-Ohno, Atsushi; Bernhard, Gert

    2016-06-07

    The complexation of Eu(iii) and Cm(iii) with the protein α-amylase (Amy), a major enzyme in saliva and pancreatic juice, was investigated over wide ranges of pH and concentration at both ambient and physiological temperatures. Macroscopic sorption experiments demonstrated a strong and fast binding of Eu(iii) to Amy between pH 5 and 8. The protein provides three independent, non-cooperative binding sites for Eu(iii). The overall association constant of these three binding sites on the protein was calculated to be log K = 6.4 ± 0.1 at ambient temperature. With potentiometric titration, the averaged deprotonation constant of the carboxyl groups (the aspartic and glutamic acid residues) of Amy was determined to be pKa = 5.23 ± 0.14 at 25 °C and 5.11 ± 0.24 at 37 °C. Time-resolved laser-induced fluorescence spectroscopy (TRLFS) revealed two different species for both Eu(iii) and Cm(iii) with Amy. In the case of the Eu(iii) species, the stability constants were determined to be log β11 = 4.7 ± 0.2 and log β13 = 12.0 ± 0.4 for Eu : Amy = 1 : 1 and 1 : 3 complexes, respectively, whereas the values for the respective Cm(iii) species were log β11 = 4.8 ± 0.1 and log β13 = 12.1 ± 0.1. Furthermore, the obtained stability constants were extrapolated to infinite dilution to make our data compatible with the existing thermodynamic database.

  4. On the abundance of Europium. [in Ap and Am stars

    Science.gov (United States)

    Hartoog, M. R.; Cowley, C. R.; Adelman, S. J.

    1974-01-01

    The inclusion of the effects of hyperfine splitting can significantly lower the abundance estimate of Eu from singly ionized lines which lie on the flat portion of the curve of growth. In the 21 cool Ap stars studied by Adelman and the five Am stars studied by Smith, the Eu abundance was reduced by 0.4 dex on the average. In individual cases, the reductions were as great as 0.9 dex. This makes the Eu abundance comparable to that of its neighboring rare earths Sm and Gd in the Ap stars and less than Sm and Gd in the Am stars, but still substantially overabundant with respect to solar values.

  5. Europium (III) and americium (III) stability constants with humic acid

    Energy Technology Data Exchange (ETDEWEB)

    Torres, R.A.; Choppin, G.R.

    1984-01-01

    The stability constants for tracer concentrations of Eu(III) and Am(III) complexes with a humic acid extracted from a lake-bottom sediment were measured using a solvent extraction system. The organic extractant was di(2-ethylhexyl)-phosphoric acid in toluene while the humate aqueous phase had a constant ionic strength of 0.1 M (NaClO/sub 4/). Aqueous humic acid concentrations were monitored by measuring uv-visible absorbances at approx.= 380 nm. The total carboxylate capacity of the humic acid was determined by direct potentiometric titration to be 3.86 +- 0.03 meq/g. The humic acid displayed typical characteristics of a polyelectrolyte - the apparent pKsub(a), as well as the calculated metal ion stability constants increased as the degree of ionization (..cap alpha..) increased. The binding data required a fit of two stability constants, ..beta../sub 1/ and ..beta../sub 2/, such that for Eu, log ..beta../sub 1/ = 8.86 ..cap alpha.. + 4.39, log ..beta../sub 2/ = 3.55 ..cap alpha.. + 11.06 while for Am, log ..beta../sub 1/ = 10.58 ..cap alpha.. + 3.84, log ..beta../sub 2/ = 5.32 ..cap alpha.. + 10.42. With hydroxide, carbonate, and humate as competing ligands, the humate complex associated with the ..beta../sub 1/ constant is calculated to be the dominant species for the trivalent actinides and lanthanides under conditions present in natural waters.

  6. Influence of the oxygen pressure on the preferred orientation and optical properties of the pulsed-laser deposited Mn{sub 1.56}Co{sub 0.96}Ni{sub 0.48}O{sub 4±δ} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Wenwen [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics & Chemistry of CAS, Urumqi 830011 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Gao, Bo [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics & Chemistry of CAS, Urumqi 830011 (China); Jiang, Chunping, E-mail: cpjiang2008@sinano.ac.cn [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics & Chemistry of CAS, Urumqi 830011 (China); Key Laboratory of Nanodevices and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics of CAS, Suzhou 215123 (China); Chang, Aimin, E-mail: changam@ms.xjb.ac.cn [Key Laboratory of Functional Materials and Devices for Special Environments of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics & Chemistry of CAS, Urumqi 830011 (China)

    2015-11-25

    Mn{sub 1.56}Co{sub 0.96}Ni{sub 0.48}O{sub 4±δ} (MCN) thin films with different oxygen pressures (in the range of 2 × 10{sup −4} to 2 Pa) are prepared on Si(100)/SiO{sub x} substrates by pulsed laser deposition technique. Effects of oxygen pressures on the microstructure and optical properties of the prepared thin films are investigated in detail. The grain sizes of films gradually decrease and the preferential orientation of the MCN films change from (400) to (113) as the oxygen pressure increases. The x-ray photoelectron spectroscopy results show that the composition of these films is proximity to that of the bulk material. In addition, the Mn{sup 3+}/Mn{sup 4+} pairs increase with an increase in the oxygen pressures increase. From spectroscopic ellipsometer spectroscopy, it is found that both the refractive index n and extinction coefficient k of the (400)-oriented films have no obvious peaks, whereas in the (113)-oriented films, peaks are exist. This feature typically originates from a change in the crystal structure as oxygen pressures increase. Furthermore, the Raman active mode (around ca. 650 cm{sup −1}) of (400) films almost disappears, whilst the active mode in (113) films remain. - Highlights: • The Mn{sub 1.56}Co{sub 0.96}Ni{sub 0.48}O{sub 4-δ} (MCN) spinel films are deposited by pulsed laser deposition process at different oxygen pressures. • The preferential orientation of the films changes from (400) plane to (113) as the oxygen pressure increases. • The E{sub g} of the (113) film is twice as large as that of the (400) film. • The Raman active mode (around ca. 650 cm{sup −1}) can be observed in the (113) films while not in the (400) film.

  7. What we do | Page 156 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Islamist Parties and Democratization : Lessons from Turkey's Justice and Development Party. The Turkish elections of November 2002 brought a new Islamic-oriented political party to power, with almost two-thirds of the seats in Parliament. Europe, Turkey, Central Asia, Far East Asia, South Asia, Iraq, Lebanon, Morocco, ...

  8. 29 CFR 1917.156 - Fuel handling and storage.

    Science.gov (United States)

    2010-07-01

    ... underground entrances, elevator shafts or other places where gas or fumes might accumulate. (2) Fuel... is exhausted. (ii) Pressure-relief valve openings shall be in continuous contact with the vapor space... transport shall be closed. Relief valves shall connect with vapor spaces. (5) Vehicle storage and servicing...

  9. Dicty_cDB: SFE156 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available llenged leaf Solanum tuberosum cDNA clone BPLI1H16 5' sequence, mRNA sequence. 42 3...Value N AL929045 |AL929045.7 Zebrafish DNA sequence from clone CH211-159J13. 42 3.6 1 BG589468 |BG589468.1 EST497310 P. infestans-cha

  10. 27 CFR 31.156 - Records of disposition.

    Science.gov (United States)

    2010-04-01

    ... losses; (3) Brand name; (4) Kind of spirits. However, this may be omitted if the dealer keeps available for inspection a separate list or record identifying “kind” with the brand name; (5) Number of...) (Approved by the Office of Management and Budget under control number 1513-0065) ...

  11. 7 CFR 1900.156 - Special handling-processing.

    Science.gov (United States)

    2010-01-01

    ... processing official notifies the applicant of the decision in writing under program regulations, subpart A of.... (g) Supervised bank account. Unless there is a clear or apparent conflict of interest, any supervised.../servicing official notifies the builder (or architect/engineer) in writing of how and from whom to request...

  12. 26 CFR 1.56A-4 - Certain taxpayers.

    Science.gov (United States)

    2010-04-01

    ... of the minimum tax in the case of estates and trusts, electing small business corporations, common trust funds, regulated investment companies, real estate investment trusts, and partnerships, see §§ 1...

  13. 156th Symposium of the International Astronomical Union

    CERN Document Server

    Kołaczek, Barbara

    1993-01-01

    In this review talk, I would like to report on the proper motion analysis, which has been recently carried out together with M. Soma and M. Yoshizawa: There has been a persistent demand in astronomy for accurate stellar positions and proper motions, which are represented by an inertial reference system constructed on the basis of a set of consistent astronomical constants. In the reference system the precessional constant plays a primary role. In a series of papers Fricke (1967a,b, 1977a,b) has deter­ mined the luni-solar precessional correction to Newcomb's value and the fictitious motion of the equinox, which have been adopted in the "IAU (1976) System of Astronomical Con­ stants". Based on the precessional correction and the equinoctial motion thus established, the fundamental reference system, the FK5 system (Fricke et al. 1988) for positions and proper motions, has been constructed. However, for several years geodetic VLBI (McCarthy & Luzum 1991) and LLR (Williams et at. 1991) observations have bee...

  14. 40 CFR 156.212 - Personal protective equipment statements.

    Science.gov (United States)

    2010-07-01

    ...: (body protection statement); (glove statement, if applicable); (footwear statement, if applicable... shall be based on the more toxic (lower numbered) category. 2 For labeling language for chemical-resistant gloves, see paragraph (f) of this section. 3 For labeling language for respiratory protection...

  15. Dicty_cDB: SHC156 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ---FSLMIKKVFQIVLKNSTSIEIWSNTLEIMKQLRIDQHENEDQSGESSITFEISELFI LDLIGKAIGPLETIELVCKFSEMFEKSKIETKLLSDWIKFGKWSLYDRPKLSYDILSLLD...---FSLMIKKVFQIVLKNSTSIEIWSNTLEIMKQLRIDQHENEDQSGESSITFEISELFI LDLIGKAIGPLETIELVCKFSEMFEKSKIETKLLSDWIKFGKWSLYDRPKLSYDILSLLD

  16. What we do | Page 156 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    provide developing-country researchers financial resources, advice, and training to help them find solutions to local problems. encourage knowledge sharing with policymakers, researchers, and communities around the world. foster new talent by offering fellowships and awards. strive to get new knowledge into the hands ...

  17. a review of 156 odontogenic tumours in calabar, nigeria

    African Journals Online (AJOL)

    2014-09-01

    Sep 1, 2014 ... 1Oral and Maxillofacial Unit, Department of Dental Surgery, University of Calabar Teaching Hospital, Cala- bar, Nigeria, 2Department of Oral ... genic tumours in our centre in order to obtain a base- line data and subsequently ..... tumour-like lesions of the oral cavity and related structures in Israeli children.

  18. 7 CFR 989.156 - Raisin diversion program.

    Science.gov (United States)

    2010-01-01

    ... the vines, spur-prune the vines, remove the bunches or take other means to preclude grapes from being... next diversion program. For spur-pruned vines, this date may be extended 2 weeks from the date of the inspection of a producer's vineyard if more than 4 bunches on spur-pruned vines are present at the time of...

  19. 40 CFR 156.66 - Child hazard warning.

    Science.gov (United States)

    2010-07-01

    ..., marketing, storage or use is remote (for example, an industrial use product); or (2) The pesticide is... hazard warning. (a) Each pesticide product must bear on the front panel of the label the statement “Keep... Toxicity Category IV products that do not otherwise require a signal word. (b) In its discretion, EPA may...

  20. Dicty_cDB: SSK156 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available tomato radicle, 5 d post-imbibition, Cornell University Lycopersicon esculentum cDNA clone cLEZ11O16...EST312837 tomato root during/after fruit set, Cornell University Lycopersicon esculentum cDNA clone cLEX14G21