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Sample records for europium iii complex

  1. Enantioselective cellular localisation of europium(iii) coordination complexes.

    Science.gov (United States)

    Frawley, Andrew T; Linford, Holly V; Starck, Matthieu; Pal, Robert; Parker, David

    2018-01-28

    The selective mitochondrial localisation of the Λ enantiomer of three different emissive europium(iii) complexes in NIH 3T3 and MCF7 cells contrasts with the behaviour of the Δ enantiomer, for which a predominant lysosomal localisation was observed by confocal microscopy. In each case, cell uptake occurs via macropinocytosis.

  2. Soluble dendrimers europium(III) β-diketonate complex for organic memory devices

    International Nuclear Information System (INIS)

    Wang Binbin; Fang Junfeng; Li Bin; You Han; Ma Dongge; Hong Ziruo; Li Wenlian; Su Zhongmin

    2008-01-01

    We report the synthesis of a soluble dendrimers europium(III) complex, tris(dibenzoylmethanato)(1,3,5-tris[2-(2'-pyridyl) benzimidazoly]methylbenzene)-europium(III), and its application in organic electrical bistable memory device. Excellent stability that ensured more than 10 6 write-read-erase-reread cycles has been performed in ambient conditions without current-induced degradation. High-density, low-cost memory, good film-firming property, fascinating thermal and morphological stability allow the application of the dendrimers europium(III) complex as an active medium in non-volatile memory devices

  3. Sparkle/PM3 for the modeling of europium(III), gadolinium(III), and terbium(III) complexes

    International Nuclear Information System (INIS)

    Freire, Ricardo O.; Rocha, Gerd B.; Simas, Alfredo M.

    2009-01-01

    The Sparkle/PM3 model is extended to europium(III), gadolinium(III), and terbium(III) complexes. The validation procedure was carried out using only high quality crystallographic structures, for a total of ninety-six Eu(III) complexes, seventy Gd(III) complexes, and forty-two Tb(III) complexes. The Sparkle/PM3 unsigned mean error, for all interatomic distances between the trivalent lanthanide ion and the ligand atoms of the first sphere of coordination, is: 0.080 A for Eu(III); 0.063 A for Gd(III); and 0.070 A for Tb(III). These figures are similar to the Sparkle/AM1 ones of 0.082 A, 0.061 A, and 0.068 A respectively, indicating they are all comparable parameterizations. Moreover, their accuracy is similar to what can be obtained by present-day ab initio effective core potential full geometry optimization calculations on such lanthanide complexes. Finally, we report a preliminary attempt to show that Sparkle/PM3 geometry predictions are reliable. For one of the Eu(III) complexes, BAFZEO, we created hundreds of different input geometries by randomly varying the distances and angles of the ligands to the central Eu(III) ion, which were all subsequently fully optimized. A significant trend was unveiled, indicating that more accurate local minima geometries cluster at lower total energies, thus reinforcing the validity of sparkle model calculations. (author)

  4. 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.

  5. 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.

  6. Synthesis and structural characterization of an unusual heterometallic europium(III) amidinate complex

    International Nuclear Information System (INIS)

    Sroor, Farid M.; Hrib, Cristian G.; Hilfert, Liane; Edelmann, Frank T.

    2015-01-01

    The reaction of EuI_2(THF)_2 with 3 equiv. of the recently discovered lithium-cyclopropylethinylamidinate Li[c-C_3H_5-C≡C-C(NCy)_2] (1) (Cy = cyclohexyl) unexpectedly afforded the heterometallic europium(III) amidinate complex [{c-C_3H_5-C≡C-C(NCy)_2}Li{c-C_3H_5-C≡C-C(NCy)_2}_2Eu(μ-I)_2Li(THF)_2] (2) in the form of bright yellow, air- and moisture-sensitive crystals. An X-ray diffraction study of 2 revealed several unusual structural features. It comprises a double ''ate'' complex of the tentative trivalent europium(III) bis(cyclopropylethinylamidinate) derivative [c-C_3H_5-C≡C-C(NCy)_2]_2Eu"I"I"II. ''Ate'' complex formation occurred not only through retention of one equiv. of lithium iodide but also through addition of one equiv. of Li[c-C_3H_5-C≡C-C(NCy)_2]. The Li atom in the iodo-bridged Eu(μ-I)_2Li(THF)_2 part of the molecule is tetrahedrally coordinated, whereas the second lithium atom is only tricoordinate through the presence of a rare monodentate (dangling) amidinate ligand. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Development of ultraviolet LED devices containing europium (III) complexes in fluorescence layer

    International Nuclear Information System (INIS)

    Iwanaga, Hiroki; Amano, Akio; Aiga, Fumihiko; Harada, Kohichi; Oguchi, Masayuki

    2006-01-01

    Relations between molecular structures of europium complexes and their luminescent properties were investigated. Europium complex with β-diketones and two different phosphine oxides 8 was highly soluble in fluorinated medium, and realized largest fluorescence intensities. The luminous intensity of ultraviolet light emitting diodes devices (LEDs) whose fluorescence layer consists of fluorinated polymer and 8 was over 200 mcd (20 mA). Fluorescence compounds of this type are promising for application in next-generation white LEDs. Moreover, we proposed a novel molecular design of europium complex with asymmetric diphosphine dioxide

  8. Spectroscopic studies of an europium(III) tris-β-diketonate complex bearing a pyrazolylpyridine ligand

    International Nuclear Information System (INIS)

    Moreira dos Santos, Antonio; Coelho, Ana C.; Almeida Paz, Filipe A.; Rocha, Joao; Goncalves, Isabel S.; Carlos, Luis D.

    2008-01-01

    A new europium(III) complex, Eu(BTA) 3 (ethyl[3-(2-pyridyl)-1-pyrazolyl]acetate) (where BTA: 1-benzoyl-3,3,3-trifluoroacetonate), was synthesised by simple ligand exchange with the solvent adduct Eu(BTA) 3 (H 2 O) 2 . The compound was characterised by elemental analysis, thermogravimetry, FTIR, FT Raman and photoluminescence spectroscopies. A significant increase of the 5 D 0 lifetime of the complex, relative to the value found for the water-coordinated adduct (from 0.657 ± 0.001 to 0.835 ± 0.002 ms), and a larger contribution of the ligand levels to the excitation spectrum indicate a better photoluminescence performance for the former complex

  9. 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.

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

    International Nuclear Information System (INIS)

    Liu, Yu; Wang, Yafei; Li, Chun; Huang, Ying; Dang, Dongfeng; Zhu, Meixiang; Zhu, Weiguo; Cao, Yong

    2014-01-01

    A novel tris(dibenzoylmethanato)[5-(2-(4-tert-butylbenzenyl)-5-benzenyl-1,3, 4-oxadiazole-4′)-1,10-phenanthroline]europium(III) [Eu(DBM) 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) 3 (BuOXD-Phen) (1–8 wt %) (80 nm)/Ba (4 nm)/Al (150 nm) were fabricated. Saturated red Eu 3+ ion emission, based on the 5 D 0 → 7 F 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 ext ) of 1.26% at current density of 1.65 mA cm −2 , with a maximum brightness of 568 cd m −2 at 137.8 mA cm −2 was achieved from the device at 1 wt % dopant concentration. - Highlights: • An oxadiazole-functionalized europium(III) complex of Eu(DBM) 3 (BuOXD-Phen) was presented. • The optophysical properties of Eu(DBM) 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

  11. Liquid crystal europium(III) β-diketonato complex with 5,5'-di(heptadecyl)-2,2'-bipyridine

    International Nuclear Information System (INIS)

    Knyazev, A.A.; Lobkov, V.S.; Galyametdinov, Yu.G.

    2004-01-01

    Liquid crystal europium(III) complex containing β-diketone and 5,5-di(heptadecyl)-2,2'-bipyridine as ligands was prepared in ethanol solution and was isolated as a yellow precipitate with 62% yield. The product was characterized by data of elementary analysis, thermography, IR spectroscopy and luminescence spectra. Temperatures of crystal-mesophase and mesophase-isotropic liquid phase transitions amount to 95 and 130 Deg C respectively [ru

  12. Photophysical studies of highly luminescent europium(III) and terbium(III) complexes functionalized with amino and mercapto groups

    Energy Technology Data Exchange (ETDEWEB)

    Souza, E.R.; Monteiro, J.H.S.K.; Mazali, I.O.; Sigoli, F.A., E-mail: fsigoli@iqm.unicam.br

    2016-02-15

    This work proposes the replacement of coordinated-water molecules from the precursor complexes [Ln(aba){sub 3}(H{sub 2}O)] and [Ln(tta){sub 3}(H{sub 2}O){sub 2}], (Ln=Eu{sup 3+}, Gd{sup 3+} or Tb{sup 3+}, aba{sup −}=aminobenzoate, tta{sup −}=thenoyltrifluoroacetonate) by the ligands mercaptobenzoate (mba{sup −}), mercaptopropionate (mpa{sup −}), phenanthroline (phen), dimethylformamide (dmf) and acetoacetanilide (aaa{sup −}), leading to anionic or neutral amino (–NH{sub 2}) or mercapto (–SH) functionalized-lantanides (III) complexes with reasonable emission quantum yields for potential application on fluorescence microscopy of biological moieties. The complexes photophysical properties were studied using luminescence spectroscopy and theoretical models to determine the transfer and back energy transfer rates and quantum yields, that were compared with experimental ones. The anionic complexes [Eu(tta){sub 3}(L)]{sup −} showed high quantum yield values and their sensitization efficiency are in the range of 39–81%. The overlay of the ground state geometries, obtained from the Sparkle/PM3 model, of the complexes [Eu(tta){sub 3}(aba)]{sup −}, [Eu(tta){sub 3}(mba)]{sup −} and [Eu(tta){sub 3}(mpa)]{sup −}, suggest similar coordination polyhedrons occupied by the europium(III). The highest transfer rates T→{sup 5}D{sub 1,0} were obtained for the anionic complexes [Eu(tta){sub 3}(L)]{sup −} which might be a result of the low triplet level energies and R{sub L} values. - Highlights: • Lanthanides functionalized-complexes. • Free mercapto and amino groups. • Covalence degree of Eu-ligands. • Energy transfer rates. • Intrinsic and absolute quantum yields and sensitization.

  13. Preparation and luminescence of silica aerogel composites containing an europium (III) phenanthroline nitrate complex

    Energy Technology Data Exchange (ETDEWEB)

    Gutzov, Stoyan, E-mail: sgutzov@chem.uni-sofia.bg [University of Sofia “St. Kliment Ohridski”, Department of Physical Chemistry, J. Bourchier Blvd. 1, 1164 Sofia (Bulgaria); Danchova, Nina; Kirilova, Rada; Petrov, Vesselin [University of Sofia “St. Kliment Ohridski”, Department of Physical Chemistry, J. Bourchier Blvd. 1, 1164 Sofia (Bulgaria); Yordanova, Stanislava [University of Sofia “St. Kliment Ohridski”, Department of Organic Chemistry, J. Bourchier Blvd. 1, 1164 Sofia (Bulgaria)

    2017-03-15

    A simple two step procedure for the functionalization of hydrophobic silica aerogel microgranules with europium ions and/or 1,10 - phenanthroline is demonstrated. The activation procedure is based on soaking aerogels in a europium nitrate solution, followed by functionalization with 1,10 – phenanthroline. The functionalized materials display strong red or blue emission at UV-excitation, coming from the formation of [Eu(phen){sub 2}](NO{sub 3}){sub 3} or Si(IV)– 1,10-phenathroline complexes in the porous system of the aerogels. The most probable site symmetry of the europium cation is C{sub 2v} confirmed by luminescence spectra analysis. Room temperature diffuse reflectance spectra and excitation/luminescence spectra are used to describe the optical properties of the hybrid composites. Excitation spectra prove an efficient energy transfer between 1,10 – phenanthroline and the Eu{sup 3+} ion. - Graphical abstract: An effective activation procedure for functionalization of silica aerogel granules with [Eu(phen){sub 2}](NO{sub 3}){sub 3} and/or 1,10 – phenanthroline /phen/ has been demonstrated in order to obtain red or blue emitting materials. Luminescence spectra (excitation at 355 nm) of functionalized aerogel granules: 1 – SiO{sub 2}:0.18phen; 2 – [Eu(phen){sub 2}](NO{sub 3}){sub 3}; 3– SiO{sub 2}:0.007Eu(phen){sub 2}(NO{sub 3}){sub 3}. The Eu{sup 3+} f-f {sup 5}D{sub 0} →{sup 7}F {sub 0,1,2,3,4} emission transitions are denoted as 0-0, 0-1, 0-2, 0-3, 0-4. The most probable site symmetry of Eu3{sup +} ion is C{sub 2v}.

  14. Solvent extraction of anionic chelate complexes of lanthanum(III), europium(III), lutetium(III), scandium(III), and indium(III) with 2-thenoyltrifluoroacetone as ion-pairs with tetrabutylammonium ions

    International Nuclear Information System (INIS)

    Noro, Junji; Sekine, Tatsuya.

    1992-01-01

    The solvent extraction of lanthanum(III), europium(III), lutetium(III), scandium(III), and indium(III) in 0.1 mol dm -3 sodium nitrate solutions with 2-thenoyltrifluoroacetone (Htta) in the absence and presence of tetrabutylammonium ions (tba + ) into carbon tetrachloride was measured. The extraction of lanthanum(III), europium(III), and lutetium(III) was greatly enhanced by the addition of tba + ; this could be explained in terms of the extraction of a ternary complex, M(tta) 4 - tba + . However, the extractions of scandium(III) and indium(III) were nearly the same when tba + was added. The data were treated on the basis of the formation equilibrium of the ternary complex from the neutral chelate, M(tta) 3 , with the extracted ion-pairs of the reagents, tta - tba + , in the organic phase. It was concluded that the degree of association of M(tta) 3 with the ion-pair, tta - tba + , is greater in the order La(tta) 3 ≅ Eu(tta) 3 > Lu(tta) 3 , or that the stability of the ternary complex in the organic phase is higher in the order La(tta) 4 - tba + ≅ Eu(tta) 4 - tba + > Lu(tta) 4 - tba + . This is similar to those of adduct metal chelates of Htta with tributylphosphate (TBP) in synergistic extraction systems. (author)

  15. Luminescence behavior of the dibenzoyl methane europium(III) complexes in sol-gel derived host materials

    International Nuclear Information System (INIS)

    Wang Feng; Fan Xianping; Wang Minquan; Zhang Xianghua

    2005-01-01

    The luminescence behavior of the dibenzoyl methane europium(III) complexes (Eu(DBM) 3 ) in sol-gel derived host materials have been investigated. The steady-state excitation and emission spectra and the time-resolved spectra of the 1% EuCl 3 and 3% DBM co-doped gel indicated an efficient ligand-to-metal energy transfer. The Eu(DBM) 3 complexes in the gel showed longer 5 D 0 lifetimes in comparison with Eu(DBM) 3 .3H 2 O complexes. The luminescence intensity of the 1% EuCl 3 and 3% DBM co-doped gel decreased continuously with increasing temperature and time of heat treatment, which indicated the gradual decomposition of the Eu(DBM) 3 complexes in the gel during heat treatment

  16. Synthesis and electroluminescence properties of europium (III) complexes with new second ligands

    International Nuclear Information System (INIS)

    Liu Ze; Wen Fushan; Li Wenlian

    2005-01-01

    Two novel second ligands, 9,9-Di-(4-methoxyphenyl)-9-H-4,5-' (OMe-Spiro-DF) and 9,9-Di-(2-(4-(4-butyloxy)phenyl)-5-phenyl-1,3,4-oxadiazolyl)-phenyl-9-H-4, 5-Diazafluorene (OXD-Spiro-DF), were successfully prepared. Europium complexes, Eu(DBM) 3 (OMe-Spiro-DF) and Eu(DBM) 3 (OXD-Spiro-DF) (DBM=dibenzolylmethane) based on the two ligands were designed and synthesized. For a double-layer device with configuration of indium tin oxide (ITO)/N, N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD)/Eu(DBM) 3 (OXD-Spiro-DF) or Eu(DBM) 3 (OMe-Spiro-DF)/Mg/Ag, compared with the device based on complex Eu(DBM) 3 (OMe-Spiro-DF), the brightness and electroluminescent (EL) efficiency of device based on complex Eu(DBM) 3 (OXD-Spiro-DF) with oxadiazole-functionalized ligand OXD-Spiro-DF are significantly improved due to the improvement of electron-transporting ability. A maximum brightness of 154 cd/m 2 was obtained at 17 V in the complex Eu(DBM) 3 (OXD-Spiro-DF), about four times brighter than the corresponding complex Eu(DBM) 3 (OMe-Spiro-DF)

  17. Sorption of small amounts of europium(III) on iron(III) hydroxide and oxide

    International Nuclear Information System (INIS)

    Music, S.; Gessner, M.; Wolf, R.H.H.

    1979-01-01

    The sorption of small amounts of europium(III) on iron(III) hydroxide and oxide has been studied as a function of pH. The mechanism of sorption is discussed. Optimum conditions have been found for the preconcentration of small or trace amounts of europium(III) by iron(III) hydroxide and oxide. The influence of complexing agents (EDTA, oxalate, tartrate and 5-sulfosalicylic acid) on the sorption of small amounts of europium(III) on iron(III) oxide has also been studied. (author)

  18. 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.

  19. Characterization of the lanthanum(III) and europium(III) trichloroacetate complexes extracted with 18-crown-6

    International Nuclear Information System (INIS)

    Imura, H.; Saito, Y.; Ohashi, K.; Meguro, Y.; Yoshida, Z.; Choppin, G.R.

    1996-01-01

    Extraction of lanthanide(III) ions with 18-crown-6 (18C6) and trichloroacetate (tca) has been studied. The composition, hydration, and structure of the La(III) and Eu(III) complexes extracted into 1,2-dichloroethane were investigated by using several methods such as the liquid-liquid distribution technique, conductimetry, Karl Fisher titration, laser luminescence spectroscopy, and 1 H NMR. The La(III) complex was found to be a monohydrate, La(tca) 3 (18C6)(H 2 O), while that of Eu(III) was a mixture of a monohydrate and a dihydrate, i.e., Eu(tca) 3 (18C6)(H 2 O) and Eu(tca) 3 (18C6)(H 2 O) 2 . The origin of the selectivity by 18C6 which gives much higher extractability of La(III) than of Eu(III) is explained by considering the hydration and probable structure of their complexes. 12 refs., 5 figs., 4 tabs

  20. Photo/electroluminescence properties of an europium (III) complex doped in 4,4'-N,N'-dicarbazole-biphenyl matrix

    International Nuclear Information System (INIS)

    Zhou Yonghui; Zhou Liang; Wu, Jing; Li, Hong-Yan; Zheng Youxuan; You Xiaozeng; Zhang Hongjie

    2010-01-01

    The photoluminescence properties of one europium complex Eu(TFNB) 3 Phen (TFNB = 4,4,4-trifluoro-1-(naphthyl)-1,3-butanedione, Phen = 1,10-phenanthroline) doped in a hole-transporting material CBP (4,4'-N,N'-dicarbazole-biphenyl) films were studied. A series of organic light-emitting devices (OLEDs) using Eu(TFNB) 3 Phen as the emitter were fabricated with a multilayer structure of indium tin oxide, 250 Ω/square)/TPD (N,N'-diphenyl-N,N'-bis(3-methyllphenyl)-(1,1'-biphenyl)-4,4'-diamine, 50 nm)/Eu(TFNB) 3 phen (x): CBP (4,4'-N,N'-dicarbazole-biphenyl, 45 nm)/BCP (2,9-dimethyl-4,7-diphenyl-l,10 phenanthroline, 20 nm)/AlQ (tris(8-hydroxy-quinoline) aluminium, 30 nm)/LiF (1 nm)/Al (100 nm), where x is the weight percentage of Eu(TFNB) 3 phen doped in the CBP matrix (1-6%). A red emission at 612 nm with a half bandwidth of 3 nm, characteristic of Eu(III) ion, was observed with all devices. The device with a 3% dopant concentration shows the maximum luminance up to 1169 cd/m 2 (18 V) and the device with a 5% dopant concentration exhibits a current efficiency of 4.46 cd/A and power efficiency of 2.03 lm/W. The mechanism of the electroluminescence was also discussed.

  1. Synthesis and characterization of the europium (III) complex as an organic luminescent material

    International Nuclear Information System (INIS)

    Zhuo Zuliang; Zhang Fujun; Xu Zheng; Lu Lifang; Li Junming; Wang Yongsheng; Lv Yuguang

    2010-01-01

    The red emission organic material Eu(coumarin) 3 ·2H 2 O complex was synthesized and its morphology, energy level alignment and luminescence characteristics were studied by using scanning electron microscopy, Fourier transform infrared spectra, cyclic voltammetry and ultraviolet-visible absorption spectra and fluorescence spectra. Eu(coumarin) 3 ·2H 2 O shows bright red emission originating from Eu 3+ ions under 345 nm light excitation. The luminescence lifetime of Eu 3+ in this complex is about 580 μs. To improve the quality of Eu(coumarin) 3 ·2H 2 O thin films, Eu(coumarin) 3 ·2H 2 O was doped with a poly(N-vinylcarbazole) (PVK) solution. The organic materials 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and aluminum quinoline (Alq 3 ) were used as hole-blocking and electron-transporting layers in our fabricated electroluminescence (EL) devices on indium tin oxide (ITO) substrates, respectively. The EL devices ITO/poly-(3,4-ethylenedioxythiophene):poly-(styrenesulphonic acid) (PEDOT:PSS)/emitting layer (PVK:Eu)/BCP/Alq 3 /Al were fabricated, and EL spectra were measured under different driving voltages. There is one emission peaking at 490 nm in addition to the characteristic emission peaks of Eu 3+ , which should be attributed to the spectral overlap between the PVK emission and electroplex emission originating from PVK and BCP interfaces. This explanation can be positively supported by the dependence of the EL spectral variation of ITO/ PVK/BCP/Alq 3 /Al devices on the driving voltage.

  2. Synthesis and characterization of the europium (III) complex as an organic luminescent material

    Science.gov (United States)

    Zhuo, Zuliang; Zhang, Fujun; Lv, Yuguang; Xu, Zheng; Lu, Lifang; Li, Junming; Wang, Yongsheng

    2010-11-01

    The red emission organic material Eu(coumarin)3·2H2O complex was synthesized and its morphology, energy level alignment and luminescence characteristics were studied by using scanning electron microscopy, Fourier transform infrared spectra, cyclic voltammetry and ultraviolet-visible absorption spectra and fluorescence spectra. Eu(coumarin)3·2H2O shows bright red emission originating from Eu3+ ions under 345 nm light excitation. The luminescence lifetime of Eu3+ in this complex is about 580 μs. To improve the quality of Eu(coumarin)3·2H2O thin films, Eu(coumarin)3·2H2O was doped with a poly(N-vinylcarbazole) (PVK) solution. The organic materials 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and aluminum quinoline (Alq3) were used as hole-blocking and electron-transporting layers in our fabricated electroluminescence (EL) devices on indium tin oxide (ITO) substrates, respectively. The EL devices ITO/poly-(3,4-ethylenedioxythiophene):poly-(styrenesulphonic acid) (PEDOT:PSS)/emitting layer (PVK:Eu)/BCP/Alq3/Al were fabricated, and EL spectra were measured under different driving voltages. There is one emission peaking at 490 nm in addition to the characteristic emission peaks of Eu3+, which should be attributed to the spectral overlap between the PVK emission and electroplex emission originating from PVK and BCP interfaces. This explanation can be positively supported by the dependence of the EL spectral variation of ITO/ PVK/BCP/Alq3/Al devices on the driving voltage.

  3. Synthesis and characterization of the europium (III) complex as an organic luminescent material

    Energy Technology Data Exchange (ETDEWEB)

    Zhuo Zuliang; Zhang Fujun; Xu Zheng; Lu Lifang; Li Junming; Wang Yongsheng [Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University), Ministry of Education, Beijing 100044 (China); Lv Yuguang, E-mail: fjzhang@bjtu.edu.c [The Provincial Key Laboratory of Biomaterials, College of Chemistry and Pharmacy, Jiamusi University, Jiamusi 154007 (China)

    2010-11-15

    The red emission organic material Eu(coumarin){sub 3{center_dot}}2H{sub 2}O complex was synthesized and its morphology, energy level alignment and luminescence characteristics were studied by using scanning electron microscopy, Fourier transform infrared spectra, cyclic voltammetry and ultraviolet-visible absorption spectra and fluorescence spectra. Eu(coumarin){sub 3{center_dot}}2H{sub 2}O shows bright red emission originating from Eu{sup 3+} ions under 345 nm light excitation. The luminescence lifetime of Eu{sup 3+} in this complex is about 580 {mu}s. To improve the quality of Eu(coumarin){sub 3{center_dot}}2H{sub 2}O thin films, Eu(coumarin){sub 3{center_dot}}2H{sub 2}O was doped with a poly(N-vinylcarbazole) (PVK) solution. The organic materials 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and aluminum quinoline (Alq{sub 3}) were used as hole-blocking and electron-transporting layers in our fabricated electroluminescence (EL) devices on indium tin oxide (ITO) substrates, respectively. The EL devices ITO/poly-(3,4-ethylenedioxythiophene):poly-(styrenesulphonic acid) (PEDOT:PSS)/emitting layer (PVK:Eu)/BCP/Alq{sub 3}/Al were fabricated, and EL spectra were measured under different driving voltages. There is one emission peaking at 490 nm in addition to the characteristic emission peaks of Eu{sup 3+}, which should be attributed to the spectral overlap between the PVK emission and electroplex emission originating from PVK and BCP interfaces. This explanation can be positively supported by the dependence of the EL spectral variation of ITO/ PVK/BCP/Alq{sub 3}/Al devices on the driving voltage.

  4. 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.

  5. Efficacy of the semiempirical sparkle model as compared to ECP ab-initio calculations for the prediction of ligand field parameters of europium (III) complexes

    International Nuclear Information System (INIS)

    Freire, Ricardo O.; Rocha, Gerd B.; Albuquerque, Rodrigo Q.; Simas, Alfredo M.

    2005-01-01

    The second version of the sparkle model for the calculation of lanthanide complexes (SMLC II) as well as ab-initio calculations (HF/STO-3G and HF/3-21G) have been used to calculate the geometries of a series of europium (III) complexes with different coordination numbers (CN=7, 8 and 9), ligating atoms (O and N) and ligands (mono, bi and polydentate). The so-called ligand field parameters, Bqk's, have been calculated from both SMLC II and ab-initio optimized structures and compared to the ones calculated from crystallographic data. The results show that the SMLC II model represents a significant improvement over the previous version (SMLC) and has given good results when compared to ab-initio methods, which demand a much higher computational effort. Indeed, ab-initio methods take around a hundred times more computing time than SMLC. As such, our results indicate that our sparkle model can be a very useful and a fast tool when applied to the prediction of both ground state geometries and ligand field parameters of europium (III) complexes

  6. Exploration of spectroscopic properties of solvated tris(thenoyltrifluoroacetonate)(2,2′-bipyridine)europium(III)red hybrid organic complex for solution processed OLEDs and displays

    Energy Technology Data Exchange (ETDEWEB)

    Chitnis, Dipti [Department of Physics, RTM Nagpur University, Nagpur 440033 (India); Thejokalyani, N., E-mail: thejokalyani@rediffmail.com [Department of Applied Physics, Laxminarayan Institute of Technology, Nagpur 440033 (India); Dhoble, S.J. [Department of Physics, RTM Nagpur University, Nagpur 440033 (India)

    2017-05-15

    In order to explore the spectroscopic properties of a novel europium activated hybrid organic tris(thenoyltrifluoroacetonate)(2,2′-bipyridine)europium(III), Eu(TTA){sub 3}bipy phosphor in various solvents at different pH and molar concentrations, UV–vis optical absorption and photoluminescence spectra were carried out. With a variation in the solvent from basic (chloroform, toluene, tetrahydrofuran) to acidic (acetic acid, formic acid) media, staggering differences in optical absorptions and optical densities were noticed with hypsochromic shift in the absorption peaks. The optical density was found to be maximum for the complex with pH= 7.0 and the intensity as well as optical density gradually decreased when pH is lowered to 6.0 or raised to 8.0 (at an interval of 0.5), proving that the complex is pH sensitive. It's optical energy gap and stokes shift values in various organic solvents were also calculated on the basis of Lippert-Mataga plot. The exploration of spectroscopic properties of solvated Eu(TTA){sub 3}bipy complex demonstrates its prospective for solution processed OLEDs and display devices. - Graphical abstract: Pictorial depiction of photoluminescence in solvated Eu(TTA){sub 3}bipy complex under UV light.

  7. Exploration of spectroscopic properties of solvated tris(thenoyltrifluoroacetonate)(2,2′-bipyridine)europium(III)red hybrid organic complex for solution processed OLEDs and displays

    International Nuclear Information System (INIS)

    Chitnis, Dipti; Thejokalyani, N.; Dhoble, S.J.

    2017-01-01

    In order to explore the spectroscopic properties of a novel europium activated hybrid organic tris(thenoyltrifluoroacetonate)(2,2′-bipyridine)europium(III), Eu(TTA) 3 bipy phosphor in various solvents at different pH and molar concentrations, UV–vis optical absorption and photoluminescence spectra were carried out. With a variation in the solvent from basic (chloroform, toluene, tetrahydrofuran) to acidic (acetic acid, formic acid) media, staggering differences in optical absorptions and optical densities were noticed with hypsochromic shift in the absorption peaks. The optical density was found to be maximum for the complex with pH= 7.0 and the intensity as well as optical density gradually decreased when pH is lowered to 6.0 or raised to 8.0 (at an interval of 0.5), proving that the complex is pH sensitive. It's optical energy gap and stokes shift values in various organic solvents were also calculated on the basis of Lippert-Mataga plot. The exploration of spectroscopic properties of solvated Eu(TTA) 3 bipy complex demonstrates its prospective for solution processed OLEDs and display devices. - Graphical abstract: Pictorial depiction of photoluminescence in solvated Eu(TTA) 3 bipy complex under UV light.

  8. Novel europium (III)-gatifloxacin complex structure with dual functionality for pH sensing and metal recognition in aqueous environment

    Science.gov (United States)

    Chen, Muhua; Zheng, Yuhui; Gao, Jinwei; Wang, Qianming

    2016-10-01

    A new type of Eu(III)-gatifloxacin complex with characteristic red luminescence has been prepared. Due to the presence of ionization effect linked to the organic chromophore, the molecular fluorescent sensor demonstrated variable pH-sensitive absorption and emission curves. The red emission derived from europium ions was strong during pH range 8-10. Between pH = 7 and 4, the europium emission remained relatively stable and fluorescence signals of gatifloxacin has been improved substantially. Under acidic conditions (pH = 1 to 3), the dramatic changes in the emission colors (from red, yellow to green) were clearly observed. Moreover, the excitation wavelength can be extended into the visible light range (Ex = 411 nm) by using the concentration effect experiment. Importantly, it gave turn-off emissions in the presence of Cu2+ or Fe3+ and the detection limits were determined to be 6.5 μM for Cu2+ and 6.2 μM for Fe3+ respectively.

  9. Luminescent amine sensor based on europium(III) chelate.

    Science.gov (United States)

    Petrochenkova, Nataliya V; Mirochnik, Anatolii G; Emelina, Tatyana B; Sergeev, Alexander A; Leonov, Andrei A; Voznesenskii, Sergey S

    2018-07-05

    The effect of methylamine vapor on luminescence of Eu(III) tris-benzoylacetonate (I) immobilized in thin-layer chromatography plates has been investigated. It has been revealed that interaction of I with analyte vapor results in increase of the intensity of Eu(III) luminescence. The mechanism of the effect of methylamine vapors on intensification of the Eu(III) luminescence has been suggested using the data of IR spectroscopy and quantum chemistry calculations. The mechanism of luminescence sensitization consists in bonding of an analyte molecule with a water molecule into the coordination sphere of Eu(III). As a result, the bond of a water molecule with the luminescence centre weakens, rigid structural fragment including europium ion, water and methylamine molecules forms. The presence of such fragment must naturally promote decrease of influence of OH-vibrations on luminescence of the complex I. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. 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.

  11. 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.

  12. Formation of americium and europium humate complexes

    International Nuclear Information System (INIS)

    Minai, Y.; Tominaga, T.; Meguro, Y.

    1991-01-01

    Binding constants of americium and europium with a humic acid were determined to study if complex formation of trivalent actinide-humates affects dissolved species of the actinides in hydrosphere. The purified humic acid was characterized by means of UV-vis, IR, and pH titration, indicating high carboxylate capacity and low aromaticity. Binding constants of americium and europium humates were determined at pH 4.6 and 6.0 by solvent extraction using 241 Am or 152 Eu as a tracer. The binding constants for americium-humate obtained preliminarily suggest that complexes with humic acid are not negligible in speciation of trivalent actinides in hydrosphere. The obtained binding constants were nearly identical with those determined previously by the same procedures, but with humic acids of different origin and compositions. (author)

  13. Statistical optimization of synthesis procedure and characterization of europium (III) molybdate nano-plates

    Energy Technology Data Exchange (ETDEWEB)

    Pourmortazavi, Seied Mahdi [Malek Ashtar University of Technology, Faculty of Material and Manufacturing Technologies, P. O. Box 16765-3454, Tehran (Iran, Islamic Republic of); Rahimi-Nasrabadi, Mehdi [Imam Hossein University, Nano Science Center, Tehran (Iran, Islamic Republic of); Fazli, Yousef [Islamic Azad University, Department of Chemistry, Faculty of Science, Arak Branch, Arak (Iran, Islamic Republic of); Mohammad-Zadeh, Mohammad [Sabzevar University of Medical Sciences, Department of Physiology and Pharmacology, School of Medicine, Sabzevar (Iran, Islamic Republic of)

    2015-06-15

    Europium (III) molybdate nano-plates were synthesized in this work via chemical precipitation route involving adding of europium (III) ion solution to the aqueous solution of molybdate reagent. Effects of some reaction variables such as concentrations of europium and molybdate ions, flow rate of europium reagent, and reactor temperature on the diameter of the synthesized europium (III) molybdate nano-plates were experimentally investigated by orthogonal array design. The results showed that the size of europium (III) molybdate nano-plates can be optimized by adjusting the concentrations of europium (III) and molybdate ions, as well as the reactional temperature. Europium (III) molybdate nano-plates prepared under the optimum conditions were characterized by X-ray powder diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. (orig.)

  14. Synthesis and spectral properties of europium phthalocyanine complexes

    International Nuclear Information System (INIS)

    Maksimova, K.N.; Bazyakina, N.L.; Kutyreva, V.V.; Suvorova, O.N.; Domrachev, G.A.

    2008-01-01

    Synthesis of europium monophthalocyanic complexes with thenoyltrifluroacetonate (tta) and ferrocenoyltrifluoroacetate (fta) ligands has been considered. Spectral characteristics of complexes PcEu(tta)(ttaH) and PcEu(fta)(ftaH) (Pc - phthalocyanine ligand) have been investigated. One of β-diketonate ligand is proposed to bind with europium ion covalently, and the second ligand saturates coordination sphere of europium due to donor-acceptor binding [ru

  15. Synthesis, crystal structure, fluorescent and antioxidation properties of cerium(III) and europium(III) complexes with bis(3-methoxysalicylidene)-3-oxapentane-1,5-diamine

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Xia; Shi, Xinkui; Xu, Yuling; Shen, Kesheng; Mao, Shanshan; Wu, Huilu [School of Chemical and Biological Engineering, Lanzhou Jiaotong University, Gansu (China)

    2017-03-02

    Two aliphatic ether Schiff base lanthanide complexes (Ln = Eu, Ce) with bis(3-methoxysalicylidene)-3-oxapentane-1,5-diamine (Bod), were synthesized and characterized by physicochemical and spectroscopic methods. [Eu(Bod)(NO{sub 3}){sub 3}] (1) is a discrete mononuclear species and [Ce(Bod)(NO{sub 3}){sub 3}DMF]{sub ∞} (2) exhibits an inorganic coordination polymer. In the two complexes, the metal ions both are ten-coordinated and the geometric structure around the Ln{sup III} atom can be described as distorted hexadecahedron. Under excitation at room temperature, the red shift in the fluorescence band of the ligand in the complexes compared with that of the free ligand can be attributed to coordination of the rare earth ions to the ligand. Moreover, the antioxidant activities of the two complexes were investigated. The results demonstrated that the complexes have better scavenging activity than both the ligand and the usual antioxidants on the hydroxyl and superoxide radicals. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Luminescent micro- and nanofibers based on novel europium phthalate complex

    Energy Technology Data Exchange (ETDEWEB)

    Enculescu, M., E-mail: mdatcu@infim.ro [National Institute of Materials Physics, Multifunctional Materials and Structures, PO Box MG-7, 77125 Magurele-Bucharest (Romania); Preda, N.; Matei, E.; Enculescu, I. [National Institute of Materials Physics, Multifunctional Materials and Structures, PO Box MG-7, 77125 Magurele-Bucharest (Romania)

    2012-09-14

    We synthesized by wet chemical route a novel europium-potassium phthalate complex Eu{sup 3+}K{sup +}[(COO){sub 2}(C{sub 6}H{sub 4})]{sub 2}. The compound is a white powder insoluble in water. X-ray diffraction evaluation shows that we obtained a new crystalline compound with no traces of the starting materials (potassium hydrogen phthalate and europium chloride). Scanning electron microscopy reveals that the powder consists of fiber-shaped structures with sizes larger than 250 nm in diameter. Energy dispersive X-ray analysis proves that the compound has a 1:1 europium-potassium ratio. Fourier transform infrared spectroscopy confirms the presence of the phthalate in the new compound. Photoluminescence and cathodoluminescence measurements show that the fiber-shaped structures are intensely luminescent with emission bands corresponding to the {sup 5}D{sub 0} {yields} {sup 7}F{sub J} (J = 1-4) Eu (III) ion's transitions in the region between 580 nm and 700 nm, the most intense maximum being observed around 615 nm. Up-converted luminescence with a maximum at 315 nm was recorded. -- Highlights: Black-Right-Pointing-Pointer A new europium-potassium phthalate complex was synthesized by wet chemical route. Black-Right-Pointing-Pointer Fiber-shaped crystalline structures with sizes larger than 250 nm. Black-Right-Pointing-Pointer The most probable structure of the molecule is [C{sub 6}H{sub 4}(COO{sup -}){sub 2}]{sub 2} K{sup +}Eu{sup 3+}. Black-Right-Pointing-Pointer Intense luminescence due to Eu{sup 3+} ions {sup 5}D{sub 0} {yields} {sup 7}F{sub J} transitions. Black-Right-Pointing-Pointer Up-converted luminescence with a maximum at 315 nm was recorded.

  17. Europium(III) complex-functionalized magnetic nanoparticle as a chemosensor for ultrasensitive detection and removal of copper(II) from aqueous solution.

    Science.gov (United States)

    Liu, Jing; Zuo, Wei; Zhang, Wei; Liu, Jian; Wang, Zhiyi; Yang, Zhengyin; Wang, Baodui

    2014-10-07

    Ultrasensitive, accurate detection and separation of heavy metal ions is very important in environmental monitoring and biological detection. In this paper, a highly sensitive and specific detection method for Cu(2+) based on the fluorescence quenching of a europium(III) hybrid magnetic nanoprobe is presented. This nanoprobe can detect Cu(2+) over a wide pH range (5.0-10.0) with a detection limit as low as 0.1 nM and it can be used for detecting Cu(2+) in living cells. After the magnetic separation, the Cu(2+) concentration decreased to 1.18 ppm, which is less than the US EPA drinking water standard (1.3 ppm), and more than 70% Cu(2+) could be removed when the amount of nanocomposite 1 reached 1 mg.

  18. Metal plasmon enhanced europium complex luminescence

    International Nuclear Information System (INIS)

    Liu Feng; Aldea, Gabriela; Nunzi, Jean-Michel

    2010-01-01

    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) 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.

  19. Inner-sphere, outer-sphere and ternary surface complexes: a TRLFS study of the sorption process of europium(III) onto smectite

    International Nuclear Information System (INIS)

    Stumpf, Th.; Fanghaenel, Th.; Bauer, A.; Kim, J.I.

    2002-01-01

    The surface sorption process of Eu(III) onto smectite was investigated by TRLFS in the trace concentration range. With increasing pH the formation of an inner-sphere Eu(III) surface complex was observed. The differences in the spectra and the fluorescence emission lifetimes of the surface sorbed Eu(III) in presence and absence of carbonate indicate the formation of ternary clay/Eu(III)/carbonate complexes /1/. (orig.)

  20. Luminescent properties of Europium(III) nitrate with 1,10-phenantroline and cinnamic acid in light - Transforming polymer materials

    Science.gov (United States)

    Kalinovskaya, I. V.; Zadorozhnaya, A. N.

    2018-04-01

    Influence of cinnamic acid on the luminescent properties of the europium(III) nitrate with 1,10-phenantroline in a polymer materials was studied. It was shown that combined use of these rare earth complexes leads to intense luminescence in the 400-700 nm region. Samples containing polymer europium nitrate with 1,10-phenantroline and cinnamic acid at a molar ratio of 1:2,0 had the maximum luminescence intensity and photostability.

  1. Design, synthesis, characterization, and OFET properties of amphiphilic heteroleptic tris(phthalocyaninato) europium(III) complexes. The effect of crown ether hydrophilic substituents.

    Science.gov (United States)

    Gao, Yingning; Ma, Pan; Chen, Yanli; Zhang, Ying; Bian, Yongzhong; Li, Xiyou; Jiang, Jianzhuang; Ma, Changqin

    2009-01-05

    Two amphiphilic heteroleptic tris(phthalocyaninato) europium complexes with hydrophilic crown ether heads and hydrophobic octyloxy tails [Pc(mCn)(4)]Eu[Pc(mCn)(4)]Eu[Pc(OC(8)H(17))(8)] [m = 12, n = 4, H(2)Pc(12C4)(4) = 2,3,9,10,16,17,23,24-tetrakis(12-crown-4)phthalocyanine; m = 18, n = 6, H(2)Pc(18C6)(4) = 2,3,9,10,16,17,23,24-tetrakis(18-crown-6)phthalocyanine; H(2)Pc(OC(8)H(17))(8) = 2,3,9,10,16,17,23,24-octakis(octyloxy)phthalocyanine] (1, 2) were designed and prepared from the reaction between homoleptic bis(phthalocyaninato) europium compound [Pc(mCn)(4)]Eu[Pc(mCn)(4)] (m = 12, n = 4; m = 18, n = 6) and metal-free H(2)Pc(OC(8)H(17))(8) in the presence of Eu(acac)(3).H(2)O (Hacac = acetylacetone) in boiling 1,2,4-trichlorobenzene. These novel sandwich triple-decker complexes were characterized by a wide range of spectroscopic methods and electrochemically studied. With the help of the Langmuir-Blodgett technique, these typical amphiphilic triple-decker complexes were fabricated into organic field effect transistors (OFET) with top contact configuration on bare SiO(2)/Si substrate, hexamethyldisilazane-treated SiO(2)/Si substrate, and octadecyltrichlorosilane (OTS)-treated SiO(2)/Si substrate, respectively. The device performance is revealed to be dependent on the species of crown ether substituents and substrate surface treatment. OFETs fabricated from the triple decker with 12-crown-4 hydrophilic substituents, 1, allow the hole transfer in the direction parallel to the aromatic phthalocyanine rings. In contrast, the devices of a triple-decker compound containing 18-crown-6 as hydrophilic heads, 2, transfer holes in a direction along the long axis of the assembly composed of face-to-face aggregated triple-decker molecules, revealing the effect of molecular structure, specifically the crown ether substituents on the film structure and OFET functional properties. The carrier mobility for hole as high as 0.33 cm(2) V(-1) s(-1) and current modulation of 7.91 x 10

  2. A novel photoluminescent and photochromic europium complex

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A ternary europium complex of 4-aminobutyric acid (ABA) with 1,10-phenanthroline (phen) [Eu2(ABA)4 (phen)4](phen)4(ClO4)6 was synthesized and characterized by X-ray single crystal diffraction. The result shows that 4-aminobutyric acid exists in zwitterion form in the binuclear complex and that the carboxylates coordinate with Eu3+ ion in bidentate bridging and tridentate chelating-bridging modes. There are two types of phen molecules, one is coordinated and the other is uncoordinated. When excited by YAG: Nd laser with 355 nm light, the title complex can emit strong red fluorescence, and its high-resolution emission spectrum was recorded at 77 K. The Eu3+ ion site is in low symmetry, which is in agreement with the result of X-ray single crystal diffraction analysis. When irradiated with a mercury lamp, the aqueous solution of the title complex can perform photochromism with the color change from colorless to green and the green color can fade away in the dark. The photochromic response time is related to the concentration and pH of the solution, the temperature and the light intensity.

  3. Enantioselective cellular localisation of europium(iii) coordination complexes† †Electronic supplementary information (ESI) available: Complex synthesis and characterisation, selected cell images showing correspondence with commercial lysosomal or mitochondrial stains and spectral imaging profiles. See DOI: 10.1039/c7sc04422d

    Science.gov (United States)

    Frawley, Andrew T.; Linford, Holly V.; Starck, Matthieu; Pal, Robert

    2017-01-01

    The selective mitochondrial localisation of the Λ enantiomer of three different emissive europium(iii) complexes in NIH 3T3 and MCF7 cells contrasts with the behaviour of the Δ enantiomer, for which a predominant lysosomal localisation was observed by confocal microscopy. In each case, cell uptake occurs via macropinocytosis. PMID:29675151

  4. Fluorimetric determination of samarium(III) and europium(III) in neodymium oxide by separation with a resin column

    Energy Technology Data Exchange (ETDEWEB)

    Shaorong Liu; Jian Meng (Beijing Research Institute of Chemical Engineering and Metallurgy (China)); Wenhua Liu (General Research Institute for Non-Ferrous Metals (China))

    1992-08-24

    When thenoyltrifluoroacetone-phenanthroline-Triton X-100 is used to determine samarium(III) and europium(III) fluorimetrically, only a limited amount of neodymium(III) can be tolerated. By using an on- line separation which can partially separate neodymium(III) from samarium(III), a practical and convenient method was developed to detect samarium(III) at concentrations >0.05% and europium(III) at concentrations >0.005% in neodymium oxide. (author). 7 refs.; 4 figs.; 3 tabs.

  5. Fluorimetric determination of samarium(III) and europium(III) in neodymium oxide by separation with a resin column

    International Nuclear Information System (INIS)

    Shaorong Liu; Jian Meng; Wenhua Liu

    1992-01-01

    When thenoyltrifluoroacetone-phenanthroline-Triton X-100 is used to determine samarium(III) and europium(III) fluorimetrically, only a limited amount of neodymium(III) can be tolerated. By using an on- line separation which can partially separate neodymium(III) from samarium(III), a practical and convenient method was developed to detect samarium(III) at concentrations >0.05% and europium(III) at concentrations >0.005% in neodymium oxide. (author). 7 refs.; 4 figs.; 3 tabs

  6. Determination of the first hydrolysis constant of Europium (III) in 3 M of ionic strength

    International Nuclear Information System (INIS)

    Ramirez B, M.E.

    1994-01-01

    The first hydrolysis constant of Eu 3+ has been determined at 303 K and 3 M (NaCl) ionic strength. A solvent extraction method was used, the extractant was dibenzoylmethane in benzene and di glycolate anion in the aqueous phase provided competitive complexation. The tracer solution was 152m1 Eu (III) in water. The radioactive solution of europium was obtained by neutron irradiation of europium nitrate solutions at pH 3.0, in a TRIGA Mark III nuclear reactor at a neutron flux of 1 x 10 13 cm -2 s -1 . The half life of the produced isotope, 152m1 Eu (9.3 h), was verified by means of a Ge H detector and no interfering radiations were observed in the spectra. (Author)

  7. Synthesis, characterization and fluorescence studies of a novel europium complex based sensor

    International Nuclear Information System (INIS)

    Li Bin; Chen Qiuyun; Wang Yachen; Huang Jing; Li Yang

    2010-01-01

    A novel europium(III) complex was synthesized using TTA (α-thenoyltrifluoroacetone) as the first ligand and H 2 bpdc (2,2'-bipyridine-3,3'-dicarboxylate) as the second ligand. Elemental analysis, thermal analysis, IR and UV-vis spectrum and fluorescence spectrum of the europium(III) complex were carried out. A characteristic Eu 3+ fluorescence emission was observed in ethanol-water (1:1) solution, indicating that the complex is stable in solution and the emission of Eu(III) ions was not influenced by the water molecules. The fluorescence emission of the complex was quenched completely by the Co 2+ and Fe 3+ ions, but the quenched emission was recovered in the presence of glycine. Moreover, the Eu 3+ emission was very sensitive to pH, so the complex can be used as pH-dependent fluorescence probe or chemosensors.

  8. Europium (III) and americium (III) stability constants with humic acid

    International Nuclear Information System (INIS)

    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 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 (α) increased. The binding data required a fit of two stability constants, β 1 and β 2 , such that for Eu, log β 1 = 8.86 α + 4.39, log β 2 = 3.55 α + 11.06 while for Am, log β 1 = 10.58 α + 3.84, log β 2 = 5.32 α + 10.42. With hydroxide, carbonate, and humate as competing ligands, the humate complex associated with the β 1 constant is calculated to be the dominant species for the trivalent actinides and lanthanides under conditions present in natural waters. (orig.)

  9. Synthesis and luminescence properties of europium and terbium complexes with pyridine- or bipyridine-linked oligothiophene ligand

    International Nuclear Information System (INIS)

    Liu Ping; Huang Mingsheng; Pan Wanzhang; Zhang Yamin; Hu Jianhua; Deng Wenji

    2006-01-01

    With an aim to develop novel luminescence materials, europium and terbium complexes of 2,5-(2-thiophene)-pyridine (TPY) and 5,5'-bis(5-(2,2'-bithiophene))-2,2'-bipyridine (B2TBPY) were synthesized, and their luminescence properties studied. The complexes exhibit ligand-sensitized emission, which is typical of Eu(III) and Tb(III) ions

  10. Thermodynamic and structural description of europium complexation in 1-octanol - H2O solutions

    International Nuclear Information System (INIS)

    Vu, T.H.; Charbonnel, M.C.; Boubals, N.; Couston, L.; Arnaud, F.

    2008-01-01

    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) 2 3+ and Eu(BTP) 3 3+ were obtained by both techniques (log(β 2 ) = 9.0 ± 0.3 and log(β 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) 2 3+ ] / [Eu(BTP) 3 3+ ] ratio. (authors)

  11. 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)

  12. Stability constants of the Europium complexes with the chloride ions

    International Nuclear Information System (INIS)

    Jimenez R, M.; Solache R, M.; Rojas H, A.

    2000-01-01

    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)

  13. Luminescent sensing of organophosphates using europium(III) containing imprinted polymers prepared by RAFT polymerization

    International Nuclear Information System (INIS)

    Southard, Glen E.; Van Houten, Kelly A.; Ott, Edward W.; Murray, George M.

    2007-01-01

    Molecularly imprinted polymers capable of sensing organophosphorous compounds by luminescence have been prepared by reversible addition fragmentation chain transfer (RAFT) polymerization. The polymer contained a dithiobenzoate substituted tris(β-diketonate) europium(III) complex which served as a polymerization substrate and as a luminescent binding site for pinacolyl methylphosphonate (PMP), the hydrolysis product of the nerve agent Soman. The resultant polymer allowed quantitation of PMP in the low ppb range with minimal interference from similar compounds. Polymers were characterized by luminescence spectroscopy and scanning electron microscopy

  14. White OLED with a single-component europium complex.

    Science.gov (United States)

    Law, Ga-Lai; Wong, Ka-Leung; Tam, Hoi-Lam; Cheah, Kok-Wai; Wong, Wing-Tak

    2009-11-16

    A new direction for white organic light-emitting devices is shown, fabricated from a novel europium complex; this single component contains a double emission center of bluish-green and red, combined to a give a pure white emission (CIE x = 0.34 and y = 0.35).

  15. Synergistic extraction of europium(III) in ammonium ionic liquid

    International Nuclear Information System (INIS)

    Rout, Alok; Venkatesan, K.A.; Antony, M.P.

    2016-01-01

    Room temperature ionic liquids have been receiving increased attention for possible applications in the area of nuclear fuel reprocessing and waste management due to their fascinating properties such as good ionicity, high solvation capability, properties tunable etc. Most of the studies in the literature on the extraction of metal ions with molecular extractants dissolved in ionic liquid diluents are making use of the hydrophobic ionic liquids containing imidazolium cations such as the 1-alkyl-3-methylimidazolium ion. From an environmental point of view, such ionic liquids are not suitable as the primary mode of the metal extraction is by cation exchange mechanism wherein ionic liquid cation is lost to the aqueous phase leading to aqueous contamination and issue of recyclability of organic phase. However, there are some hydrophobic ionic liquids such as trioctylmethylammonium chloride ((N 1888 )(Cl)), and trihexyl(tetradecyl)phoshonium chloride (Cyphos IL 101) that exhibit no cation exchange in the aqueous phase during extraction. In this context, the extraction behavior of europium(III) using a neutral extractant, octyl, phenyl-N.N-diisobutylmethylcarbamoylphophinoxide (CMPO) and/or an acidic extractant bis(ethylhexyl)phosphoric acid (D2EHPA) dissolved in the ammonium ionic liquid diluent, trioctylmethylammonium bis(trifluoromethanesulfonyl)imide, (N 1888 )(NTf 2 ). The extraction behavior of CMPO (or D2EHPA)/(N 1888 )((Tf 2 ) system was investigated as a function of different extraction parameters such as feed acidity, extractant concentration, equilibration time etc.

  16. Effect of heptadentate (N{sub 4}O{sub 3}) tripodal Schiff base ligand and its yttrium(III) complex on the luminescence and extraction of tris({beta}-diketonato)europium(III)

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Y. [Department of Chemistry, Faculty of Science, Science University of Tokyo, Tokyo 162-8601 (Japan)], E-mail: yhasegaw@rs.kagu.tus.ac.jp; Saitou, S.; Nagaoka, D.; Yajima, H. [Department of Chemistry, Faculty of Science, Science University of Tokyo, Tokyo 162-8601 (Japan); Kanesato, M. [National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8562 (Japan)

    2008-02-28

    In order to learn the effect of a Schiff base and the complex of Y{sup III} on the extraction of Eu{sup III} with {beta}-diketones and on the luminescence of the extracted species, the extraction of Eu{sup III} with 2-thenoyltrifluoroacetone (Htta) and/or these Schiff bases, tris(5-t-butyl)salicylidenaminoethyl amine (H{sub 3}L{sup 1}), and its Y{sup III} complex ([YL{sup 1}]) prepared, into CHCl{sub 3} was examined. Further, the luminescence and excited spectra of CHCl{sub 3} phases extracted Eu{sup III} complexes and the solutions containing tris({beta}-diketonato)Eu{sup III} and/or the Schiff bases were measured. On the measurement of the luminescence spectra, tris(pivaloyltrifluoroacetonato)Eu{sup III} (Eu(pta){sub 3}) as well as Eu(tta){sub 3} was used. Synergistic effect with Htta and these Schiff bases was observed. However, proper effect of Y{sup III} was not observed. The luminescence intensity of Eu(tta){sub 3} at 613 nm decreased with increasing concentration of H{sub 3}L{sup 1} or [YL{sup 1}], whereas that of Eu(pta){sub 3} increased with increasing concentration of the ligands, but no difference between both Schiff bases was observed, because of picking up of Y{sup III} from [YL{sup 1}] with the interaction between [YL{sup 1}] and water.

  17. Sensitive determination of adenosine disodium triphosphate in soil, milk, and pharmaceutical formulation by enoxacin–europium (III) fluorescence complex in solution

    International Nuclear Information System (INIS)

    Alam, Al-Mahmnur; Kamruzzaman, Mohammad; Hak Lee, Sang; Ho Kim, Young; Jin Jo, Hae; Hong Kim, Sung; Park, Sang-Ryoul

    2012-01-01

    A new spectroflurometric method for the determination of adenosine disodium triphosphate (ATP) is developed. Fluorometric interaction between ATP and enoxacin (ENX)–Eu 3+ complex was studied using UV–vis and fluorescence spectroscopy. Weak luminescence spectra of Eu 3+ were enhanced after complexation with ENX at 589 nm and 614 nm upon excitation at 395 nm due to energy transfer from the ligand to the lanthanide ion. It was observed that luminescence spectrum of Eu 3+ was strongly enhanced further at 614 nm after incorporation of ATP into the ENX–Eu 3+ complex. Under optimal conditions, the enhancement of luminescence at 614 nm was responded linearly with the concentration of ATP. The linearity was maintained in the range of 1.5×10 −10 –1.15×10 −8 M (R=0.9973) with the limit of detection (3σ) of 4.71×10 −11 M. The relative standard deviation (RSD) for 9 repeated measurements of 1×10 −9 M ATP was 1.25%. Successful determinations of ATP in soil, milk, and a pharmaceutical formulation with the proposed method were demonstrated. - Highlights: ► Weak luminescence of Eu 3+ was enhanced at 614 nm after formation of complex with ENX. ► Energy transfer occurs through FRET from ENX to Eu 3+ upon excitation. ► Luminescence signal was further enhanced when ATP conjugates with ENX–Eu 3+ complex. ► Luminescence intensity of Eu 3+ at 614 nm was correlated with concentration of ATP. ► The method was applied to determine ATP in soil, milk, and pharmaceutical samples.

  18. Sorption behavior of europium(III) and curium(III) on the cell surfaces of microorganisms

    International Nuclear Information System (INIS)

    Ozaki, T.; Kimura, T.; Ohnuki, T.; Yoshida, Z.; Gillow, J.B.; Francis, A.J.

    2004-01-01

    We investigated the association of europium(III) and curium(III) with the microorganisms Chlorella vulgaris, Bacillus subtilis, Pseudomonas fluorescens, Halomonas sp., Halobacterium salinarum, and Halobacterium halobium. We determined the kinetics and distribution coefficients (K d ) for Eu(III) and Cm(III) sorption at pH 3-5 by batch experiments, and evaluated the number of water molecules in the inner-sphere (N H 2 O ) and the degree of strength of ligand field (R E/M ) for Eu(III) by time-resolved laser-induced fluorescence spectroscopy (TRLFS). Exudates from C. vulgaris, Halomonas sp., and H. halobium had an affinity for Eu(III) and Cm(III). The log K d of Eu(III) and Cm(III) showed that their sorption was not fully due to the exchange with three protons on the functional groups on cell surfaces. The halophilic microorganisms (Halomonas sp., Halobacterium salinarum, H. halobium) showed almost no pH dependence in log K d , indicating that an exchange with Na + on the functional groups was involved in their sorption. The ΔN H 2 O (= 9 - N H 2 O ) for Eu(III) on C. vulgaris was 1-3, while that for the other microorganisms was over 3, demonstrating that the coordination of Eu(III) with C. vulgaris was predominantly an outer-spherical process. The R E/M for Eu(III) on halophilic microorganisms was 2.5-5, while that for non-halophilic ones was 1-2.5. This finding suggests that the coordination environment of Eu(III) on the halophilic microorganisms is more complicated than that on the other three non-halophilic ones. (orig.)

  19. Sorption behavior of europium(III) and curium(III) on the cell surfaces of microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Ozaki, T.; Kimura, T.; Ohnuki, T.; Yoshida, Z. [Advanced Science Research Center, Japan Atomic Energy Research Inst., Ibaraki (Japan); Gillow, J.B.; Francis, A.J. [Environmental Sciences Dept., Brookhaven National Lab., Upton, NY (United States)

    2004-07-01

    We investigated the association of europium(III) and curium(III) with the microorganisms Chlorella vulgaris, Bacillus subtilis, Pseudomonas fluorescens, Halomonas sp., Halobacterium salinarum, and Halobacterium halobium. We determined the kinetics and distribution coefficients (K{sub d}) for Eu(III) and Cm(III) sorption at pH 3-5 by batch experiments, and evaluated the number of water molecules in the inner-sphere (N{sub H{sub 2}O}) and the degree of strength of ligand field (R{sub E/M}) for Eu(III) by time-resolved laser-induced fluorescence spectroscopy (TRLFS). Exudates from C. vulgaris, Halomonas sp., and H. halobium had an affinity for Eu(III) and Cm(III). The log K{sub d} of Eu(III) and Cm(III) showed that their sorption was not fully due to the exchange with three protons on the functional groups on cell surfaces. The halophilic microorganisms (Halomonas sp., Halobacterium salinarum, H. halobium) showed almost no pH dependence in log K{sub d}, indicating that an exchange with Na{sup +} on the functional groups was involved in their sorption. The {delta}N{sub H{sub 2}O} (= 9 - N{sub H{sub 2}O}) for Eu(III) on C. vulgaris was 1-3, while that for the other microorganisms was over 3, demonstrating that the coordination of Eu(III) with C. vulgaris was predominantly an outer-spherical process. The R{sub E/M} for Eu(III) on halophilic microorganisms was 2.5-5, while that for non-halophilic ones was 1-2.5. This finding suggests that the coordination environment of Eu(III) on the halophilic microorganisms is more complicated than that on the other three non-halophilic ones. (orig.)

  20. Luminescent properties of europium different-ligand complexes with cyclic. beta. -diketones and diantipyrylalkanes

    Energy Technology Data Exchange (ETDEWEB)

    Ul' yanova, T M; Gerasimenko, G N; Tishchenko, M A; Vitkun, R A [AN Ukrainskoj SSR, Odessa. Fiziko-Khimicheskij Inst.

    1983-03-01

    Using luminescence method different-ligand complexing of europium ions with diantipyrylalkanes and cyclic ..beta..-diketones: 2-acetyl- and 2-benzoyl-1.3-indandions, has been studied. The optimum conditions of the formation of different-ligand complexes and the ratio of components in it are determined. Effect of alien lanthanides and diantipyrylmethane derivatives on the luminescence intensity of europium complexes is clarified. A correlation between the ratio of the luminescence intensity bands of europium complexes and the values of oscillator strengths of supersensitive transitions of neodymium and erbium absorption bands is established.

  1. Temperature effects on the interaction mechanisms between the europium (III) and uranyl ions and zirconium diphosphate

    International Nuclear Information System (INIS)

    Finck, N.

    2006-10-01

    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)

  2. Synthesis and spectroscopic behavior of highly luminescent trinuclear europium complexes with tris-β-diketone ligand

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dunjia, E-mail: dunjiawang@163.com; Pi, Yan; Liu, Hua; Wei, Xianhong; Hu, Yanjun; Zheng, Jing

    2014-11-15

    Highlights: • Synthesis of the tris-β-diketone ligand and its trinuclear europium complexes. • Photoluminescence behavior of trinuclear europium complexes. • Analysis of the Judd–Ofelt intensity parameters (Ω{sub t}), lifetime (τ) and quantum yield (η). - Abstract: A new tris-β-diketone ligand, 2-[4,6-bis-(1-benzoyl-2-oxo-2-phenyl-ethyl)-[1,3,5]triazin-2-yl] -1,3-diphenyl-propane-1,3-dione (H{sub 3}L), and its trinuclear europium complexes, Eu{sub 3}(DBM){sub 6}L (C1), Eu{sub 3}(DBM){sub 6}(Bipy){sub 3}L (C2) and Eu{sub 3}(DBM){sub 6}(Phen){sub 3}L (C3) were synthesized and their spectroscopic behaviors were studied by FT-IR, {sup 1}H NMR, UV–vis and photoluminescence spectroscopic techniques. These europium complexes exhibited the characteristic emission bands that arise from the {sup 5}D{sub 0} → {sup 7}F{sub J} (J = 0–4) transitions of the europium ion in solid state. The Ω{sub 2} and Ω{sub 4} intensity parameters, lifetime (τ) and luminescence quantum yield (η) were calculated according to the emission spectra and luminescence decay curves in solid state. The results indicated that these trinuclear europium complexes displayed a longer lifetime (τ) and higher luminescence quantum efficiency (η), especially complexes C2 (τ = 0.820 ms, η = 46.5%) and C3 (τ = 0.804 ms, η = 47.4%), which due to the effect of two additional europium ion lumophors and the introduction of the third ligands, Bipy or Phen in trinuclear complexes. Their Ω{sub 2} values demonstrated that the europium ion in these complexes is in a highly polarizable chemical environment.

  3. Photoluminescent behaviors of several kinds of europium ternary complexes doped in PMMA

    International Nuclear Information System (INIS)

    Liu, H.-G.; Lee, Yong-Ill; Park, Seongtae; Jang, Kiwan; Kim, Sang Su

    2004-01-01

    Four kinds of europium ternary complexes; Eu(DBM) 3 phen, Eu(DBM) 3 (DB-bpy), Eu(DBM) 3 (DN-bpy) and Eu(DBM) 3 biq (DBM, phen, DB-bpy, DN-bpy and biq refer to Dibenzoylmethane, 1,10-phenanthroline, 4,4'-Di-tert-butyl-2,2'-dipyridyl, 4,4'-Dinonyl-2,2'-dipyridyl and 2,2'-Biquinoline, respectively), were doped in poly(methyl methacrylate) (PMMA) matrix. The luminescence properties of the composites were investigated by emission spectroscopy and lifetime measurements. It was found that the composites formed by the three complexes, Eu(DBM) 3 phen, Eu(DBM) 3 (DB-bpy), and Eu(DBM) 3 (DN-bpy), exhibit strong luminescence and similar emission spectral characteristics to Eu(III). Whereas, Eu(DBM) 3 biq shows large differences in its luminescence spectrum compared to those of other complexes. The luminescence was very weak and broad. The emission spectral features of Eu(III) in the Eu(DBM) 3 biq/PMMA systems change with the molar ratios of the complex and PMMA. The lifetime of 5 D 0 level of Eu(III) in Eu(DBM) 3 biq/PMMA systems is shorter than those in the other systems. The luminescence intensity of Eu(III) in Eu(DBM) 3 biq/PMMA systems decreases gradually when exposed to UV-light while the broad emission band becomes stronger

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

    International Nuclear Information System (INIS)

    Cai, Huan; Zhao, Fang; Si, Hailin; Zhang, Shuaishuai; Wang, Chunchun; Qi, Peirong

    2012-01-01

    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 -9 - 7.0 Χ 10 -7 mol L -1 with a detection limit of 1.3 Χ 10 -9 mol L.1 (3σ). The relative standard deviation (RSD) was 1.7% (n = 11) for 5.0 Χ 10 -8 mol L -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

  5. Luminescence properties of europium (III) cryptates trapped in sol-gel glass

    International Nuclear Information System (INIS)

    Zaitoun, M.A.; Kim, T.; Jaradat, Q.M.; Momani, K.; Qaseer, H.A.; El-Qisairi, A.K.; Qudah, A.; Radwan, N.E.

    2008-01-01

    The Lanthanide complexes Eu-2.2.1 and Eu-2.2.2 were synthesized and then incorporated into silica based transparent organic-inorganic hybrid material by the sol-gel method as an example of how doped xerogel materials are emerging as an important means of producing new materials. The produced gels were diagnosed to monitor emission spectra of the luminescent trivalent europium (Eu 3+ ) complexes; emissions were compared to those for gels containing uncomplexed Eu 3+ . Results of the experiments (emission and lifetimes) concerning the coordination sphere composition showed that a cryptand ligand with aromatic groups (short range effect) and the hydrophobic gel host (long range effect) settle efficient action in the antenna effect and isolate the central ion from efficient quenchers, as e.g. water molecules. Each ligand imposed a distinct splitting pattern on the europium emission bands that helps identify them

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

    International Nuclear Information System (INIS)

    Kaczmarek, Malgorzata; Lis, Stefan

    2009-01-01

    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 -7 to 2 x 10 -5 mol L -1 of Chlor-TC; 2 x 10 -7 to 2 x 10 -5 mol L -1 of Oxy-TC and 1 x 10 -7 to 3 x 10 -5 mol L -1 of Doxy-TC. The method was successfully applied to the determination of these drugs in pharmaceutical and veterinary formulation and honey.

  7. 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 [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.

  8. Detection of Molecular Chirality by Induced Resonance Raman Optical Activity in Europium Complexes

    Czech Academy of Sciences Publication Activity Database

    Yamamoto, Shigeki; Bouř, Petr

    2012-01-01

    Roč. 51, č. 44 (2012), s. 11058-11061 ISSN 1433-7851 R&D Projects: GA MŠk(CZ) LH11033; GA ČR GAP208/11/0105 Institutional support: RVO:61388963 Keywords : europium * complexes * raman optical activity * resonance Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 13.734, year: 2012

  9. Photoluminescent study of Polycarbonate (PC) and Poly(9-vinylcarbazole) (PVK) doped films with europium complex

    International Nuclear Information System (INIS)

    Forster, Pedro Lima

    2010-01-01

    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) 3 (H 2 0) 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) 3 (H 2 0) 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 5 D 0 -→ 7 F J transitions (J = 0-4) of Eu 3+ ion indicate the incorporation of the Eu 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)

  10. 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.

  11. Is the stoichiometry of the europium nitrate complexes with neutral organophosphorus extractants be anticipated?

    International Nuclear Information System (INIS)

    Beudaert, Ph.; Lamare, V.; Wipff, G.

    2001-01-01

    Molecular dynamics simulations have been performed in water on europium nitrate complexes with three neutral organophosphorus extractants (TBP, TPPO and CMPO) in order to determine on what criteria it is possible to obtain by simulations the experimental 1:3 stoichiometry in organic solution. This stoichiometry was investigated by progressive saturation of the cation coordination sphere. When the nitrate counter-ions are bidentate, the 1:3 stoichiometry corresponds to the degree of saturation where the interaction energy between europium and water becomes repulsive. Beyond this stoichiometry, complexes with TPPO and CMPO are unstable, although a 1:4 complex with TBP may exist but its formation appears to be energetically unfavored. (author)

  12. Chemical states and electronic properties of the interface between aluminium and a photoluminescent conjugated copolymer containing europium complex

    International Nuclear Information System (INIS)

    Cai, Q.J.; Ling, Q.D.; Li, S.; Zhu, F.R.; Huang, Wei; Kang, E.T.; Neoh, K.G.

    2004-01-01

    The chemical states and electronic properties of the interface between thermally evaporated aluminium and a photoluminescent conjugated copolymer containing 9,9'-dihexylfluorene and europium complex-chelated benzoate units in the main chain (PF6-Eu(dbm) 2 phen) were studied in situ by X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). The changes in C 1s, Eu 3d, N 1s, and Al 2p core-level lineshapes with progressive deposition of aluminium atoms were carefully monitored. Aluminium was found to interact with the conjugated backbone of the copolymer to form the Al carbide, Al-O-C complex, and Al(III)-N chelate at the interface. In addition, the europium ions were reduced to the metallic state by the deposited aluminium atoms, which were oxidized and chelated by the 1,10-phenanthroline ligands (phen). The changes in chemical states at the interface suggest that the intramolecular energy transfer process in this copolymer had been affected. Moreover, aluminium also interacted with the bulk-adsorbed oxygen, which migrates to the surface in response to the deposition of aluminium atoms, to form a layer of metal oxides. On the other hand, the evolution of the UPS spectra suggests that the π-states of the conjugated system were affected and an unfavorable dipole layer was induced by the deposited aluminium atoms

  13. Cobalt(III) complex

    Indian Academy of Sciences (India)

    Administrator

    e, 40 µM complex, 10 hrs after dissolution, f, 40 µM complex, after irradiation dose 15 Gy. and H-atoms result in reduction of Co(III) to Co. (II). 6. It is interesting to see in complex containing multiple ligands what is the fate of electron adduct species formed by electron addition. Reduction to. Co(II) and intramolecular transfer ...

  14. 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.

  15. Spectroscopic studies of europium-tetracyclines complexes and their applications in detection of hydrogen peroxide and urea peroxide

    International Nuclear Information System (INIS)

    Grasso, Andrea Nastri

    2010-01-01

    In this work were studied the spectroscopic properties of trivalent europium ion complexed with components of tetracycline family, chlorotetracycline, oxytetracycline and metacycline, in the presence of hydrogen peroxide and urea peroxide. Optical parameters were obtained such as absorption, emission, lifetime and calibration curves were constructed for luminescence spectra. Experiments were carried out with both inorganic compounds and europium-tetracyclines complexes in order to verify possible interferences. Studies for glucose determination were also described using europium-tetracyclines complexes as biosensors. Results show that europium tetracyclines complexes emit a narrow band in the visible region and, in the presence of hydrogen peroxide or urea peroxide there is a greater enhancement in their luminescence and lifetime. Thus, europium-tetracyclines complexes studied can be used as biosensors for hydrogen and urea peroxides determination as a low cost and room temperature method. An indirect method for glucose determination was studied by adding glucose oxidase enzyme in europium-tetracyclines complex in the presence of glucose promoting as product hydrogen peroxide. (author)

  16. The different-ligand complexing of europium with complexones and β-diketones in micellar solution

    International Nuclear Information System (INIS)

    Svetlova, I.E.; Dobrynina, N.A.; Smirnova, N.S.; Martynenko, L.I.; Evseev, A.M.; Savitskij, A.P.

    1989-01-01

    Method of pH-metric titration with mathematical simulation was used to study the effect of nonionic surfactant (polyoxyethyleneoctylphenyl este) on stability of europium complexes with cyclohexanediaminetetraacetic and ethylenediaminetetraacetic acids. Optimal conditions for ternary complex formation in the system Eu 3+ -complexone-β-diketone at pH 7.0-9.0 were found. Complex-compositions were determined and their stability constants were calculated. It is shown that complex stability decreases by several orders in micellar solutions, tecause β-diketone introduction to the solution decreases thermodynamic stability of complexes

  17. Improved efficiency of organic light-emitting diodes based on a europium complex by fluorescent dye

    Energy Technology Data Exchange (ETDEWEB)

    You Han [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Fang Junfeng [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Gao Jia [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Ma Dongge [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China)]. E-mail: mdg1014@ciac.jl.cn

    2007-01-15

    Improved efficiency of organic light-emitting diodes (OLEDs) based on europium complexes have been realized by using a fluorescent dye 4-(dicyanomethylene)-2-t-butyl-6 (1,1,7,7-tetramethyljulolidyl-9-enyl))-4H-pyran (DCJTB) doping .The luminous efficiency of the devices with a fluorescent dye in the emissive layer was found to improve two times of that in devices without fluorescent dye. The devices showed pure red light, which is the characteristic emission of trivalent europium ion with a full-width at half-maximum of 3 nm.The maximum brightness and luminous efficiency reached 1200 cd/m{sup 2} at 23 V and 7.3 cd/A (2.0 lm/w), respectively, at a current density of 0.35 mA/cm{sup 2}.

  18. Temperature dependence of the luminescence lifetime of a europium complex immobilized in different polymer matrices

    Energy Technology Data Exchange (ETDEWEB)

    Basu, Bharathi Bai J. [Surface Engineering Division, National Aerospace Laboratories, Bangalore 560017 (India)], E-mail: bharathi@css.nal.res.in; Vasantharajan, N. [Surface Engineering Division, National Aerospace Laboratories, Bangalore 560017 (India)

    2008-10-15

    The temperature dependence of the luminescence lifetime of temperature sensor films based on europium (III) thenoyltrifluoroacetonate (EuTTA) as sensor dye in various polymer matrices such as polystyrene (PS), polymethylmethacrylate (PMMA), polyurethane (PU) and model airplane dope was studied and compared. The luminescence lifetime of EuTTA was found to depend on the polymer matrix. The temperature sensitivity of lifetime was maximum for EuTTA-PS coating in the temperature range of 10-60 deg. C. The effect of concentration of the sensor dye in the polymer on the lifetime and temperature sensitivity was also studied.

  19. The condition for electroplex emission from an europium complex doped poly( N-vinylcarbazole)

    Science.gov (United States)

    Zhang, T.; Xu, Z.; Qian, L.; Tao, D. L.; Teng, F.; Gao, X.; Xu, X. R.

    2005-10-01

    Spectral characteristics of photoluminescence (PL) and electroluminescence (EL) of poly( N-vinylcarbazole) (PVK) matrices doped with a novel europium complex Eu(aspirin) 3phen were investigated. A red-shift and broadening were observed in the EL spectra but not in the PL ones. However, neither red-shift nor broadening were observed in the EL spectra of PVK doped with a similar complex with the same ligand, terbium complex (Tb(aspirin) 3phen). This result suggests the formation of electroplexes in blend systems, which is likely due to inefficient energy transfer from host molecules to dopant molecules.

  20. Determination of the hydrolysis constants of Europium (III), in ion strength media 4, 5 and 6 M NaClO4 at 303 K

    International Nuclear Information System (INIS)

    Alvarado B, A.; Jimenez R, M.; Solache R, M.

    1999-01-01

    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 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)

  1. Synthesis of mixed ligand europium complexes: Verification of predicted luminescence intensification

    International Nuclear Information System (INIS)

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

    2016-01-01

    Mixed ligand europium complexes are predicted to be more luminescent than what would be expected from their corresponding repeating ligand compounds according to a conjecture recently advanced by our research group; a conjecture that has already been validated for strongly luminescent europium complexes. In this article, we seek to further verify the validity of this conjecture for complexes which are much more symmetric, and which thus display lower levels of luminescence. Accordingly, we synthesized complexes Eu(DBM) 3 (L) 2 , and all novel mixed ligand combinations Eu(DBM) 3 (L,L') with L and L' equal to DBSO, PTSO, and TPPO. The syntheses were carried out via displacement reactions from the starting complex Eu(DBM) 3 (H 2 O) 2 , passing through the intermediates Eu(DBM) 3 (L) 2 and finally, by displacement of L by L', arriving at Eu(DBM) 3 (L,L'). The ligands L obey the following order of displacement TPPO>PTSO>DBSO>H 2 O, which had been previously described by our group. In the present article, we further show that this displacement order could have been predicted by Sparkle/RM1 thermochemical calculations. Subsequently, we determined the radiative decay rates, A rad , for all six compounds by photophysical measurements. As expected, results show that the measured A rad values for all novel mixed ligand complexes are larger than the average of the A rad values for the corresponding repeating ligand coordination compounds. In conclusion, the present article does broaden the scope of our conjecture, which enunciates that an increase in the diversity of ligands around the europium ion tends to intensify the luminescence. - Highlights: • Mixed ligand europium complexes are predicted to be more luminescent than repeating ligand ones. • Radiative decay rates increase with structural coordination asymmetry. • The non-ionic ligands displacement order in substitution reactions is TPPO>PTSO>DBSO>H 2 O. • Sparkle/RM1 correctly predicts the

  2. Insight into the Extraction Mechanism of Americium(III) over Europium(III) with Pyridylpyrazole: A Relativistic Quantum Chemistry Study.

    Science.gov (United States)

    Kong, Xiang-He; Wu, Qun-Yan; Wang, Cong-Zhi; Lan, Jian-Hui; Chai, Zhi-Fang; Nie, Chang-Ming; Shi, Wei-Qun

    2018-05-10

    Separation of trivalent actinides (An(III)) and lanthanides (Ln(III)) is one of the most important steps in spent nuclear fuel reprocessing. However, it is very difficult and challenging to separate them due to their similar chemical properties. Recently the pyridylpyrazole ligand (PypzH) has been identified to show good separation ability toward Am(III) over Eu(III). In this work, to explore the Am(III)/Eu(III) separation mechanism of PypzH at the molecular level, the geometrical structures, bonding nature, and thermodynamic behaviors of the Am(III) and Eu(III) complexes with PypzH ligands modified by alkyl chains (Cn-PypzH, n = 2, 4, 8) have been systematically investigated using scalar relativistic density functional theory (DFT). According to the NBO (natural bonding orbital) and QTAIM (quantum theory of atoms in molecules) analyses, the M-N bonds exhibit a certain degree of covalent character, and more covalency appears in Am-N bonds compared to Eu-N bonds. Thermodynamic analyses suggest that the 1:1 extraction reaction, [M(NO 3 )(H 2 O) 6 ] 2+ + PypzH + 2NO 3 - → M(PypzH)(NO 3 ) 3 (H 2 O) + 5H 2 O, is the most suitable for Am(III)/Eu(III) separation. Furthermore, the extraction ability and the Am(III)/Eu(III) selectivity of the ligand PypzH is indeed enhanced by adding alkyl-substituted chains in agreement with experimental observations. Besides this, the nitrogen atom of pyrazole ring plays a more significant role in the extraction reactions related to Am(III)/Eu(III) separation compared to that of pyridine ring. This work could identify the mechanism of the Am(III)/Eu(III) selectivity of the ligand PypzH and provide valuable theoretical information for achieving an efficient Am(III)/Eu(III) separation process for spent nuclear fuel reprocessing.

  3. Synthesis of red fluorescent graphene quantum dot-europium complex composites as a viable bio imaging platform

    International Nuclear Information System (INIS)

    Liu, Yanting; Fan, Louzhen; Zhou, Shixin; Fan, Hong

    2016-01-01

    We have prepared graphene quantum dot-europium(III) complex composites by noncovalently connecting chelating ligands dibenzoylmethane (DBM) and 1,10-phenanthroline (Phen) with graphene quantum dots (GQDs) first, followed by coordination to Eu(III). The resulting composites are well water-soluble and display red fluorescence of high color purity. The composites were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction. Aqueous solutions of the composites under 365 nm excitation display fluorescence with a peak at 613 nm and a quantum yield as high as 15.5 %. The good water solubility and stable photoluminescence make the composites very different from other Eu(III)-based coordination complexes. The composites are cell viable and can be used to label both the cell membrane and the cytoplasm of MCF-7 cells. They are also shown to act as bioprobes for in-vivo localization of tumorous tissue. In our perception, such composites are expected to possess wide scope because of the many functionalizations that are possible with GQDs. (author)

  4. Effect of temperature on the extraction of europium (III) bymixtures of neutral phosphoro-organic extractants from nitrate solutions

    International Nuclear Information System (INIS)

    Milchlin, E.B.; Khmuran, M.A.; Mikhailichenko, A.I.

    1986-01-01

    A study has been made of the distribution of microquantities of europium (III) on extraction with neutral phosphoorganic compounds-tri-n-butyl phosphate (TBP), diisooctylmethyl phosphonate (DIOMP),trialkylphosphine oxide with dissimilar radicals (PODR), or mixtures thereof-from a solution of 2 mole/liter NH 4 NO 3 and 0.01 mole/liter HNO 3 , in the temperature range 20-60 0 C. A temperature rise results in a decrease of the distribution coefficients of the europium on extraction by all of the extractants tested and their mixtures, and also in a reduction of the synergistic effect in extraction by mixtures of the extractants. Based on an investigation of the temperature dependences of the distribution constants of europium nitrate upon extraction by TBP, DIOMP, PODR, or their mixtures, values have been determined for the enthalpy, free energy, and entropy of extraction. It is shown that the enthalpy (-ΔH) increases in the order TBP< DIOMP< PODR. In an extraction with mixed extractants, the enthalpy has a value intermediate between those with the individual extractants. The entropy of extraction (-ΔS) increases in the reverse order PODR< DIOMP< TBP

  5. A spectroscopic screening of the chemical speciation of europium(III) in gastrointestinal tract. The intestine

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, Claudia; Barkleit, Astrid [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Chemistry of the F-Elements

    2016-07-01

    To evaluate the health risks of lanthanides (Ln) and radiotoxic actinides (An), investigations into the chemical reactions of these metals in the human gastrointestinal tract are necessary. In order to identify the dominant binding partners (i.e. counter ions and/or ligands) of An/Ln in the gastrointestinal tract, a spectroscopic screening was performed by Time-Resolved Laser-induced Fluorescence Spectroscopy (TRLFS) using artificial digestive juices containing Eu(III), a representative of Ln(III) and An(III). In the intestine, Eu(III) show a strong complexation especially with organic substances of the pancreatic and bile juice like the protein mucin.

  6. Adsorption and desorption of radionuclide europium(III) on multiwalled carbon nanotubes studied by batch techniques

    International Nuclear Information System (INIS)

    Songsheng Lu; Junzheng Xu; Caicai Zhang; Zhiwei Niu

    2011-01-01

    The adsorption of Eu(III) on multiwalled carbon nanotubes (MWCNTs) as a function of pH, ionic strength and solid contents are studied by batch technique. The results indicate that the adsorption of Eu(III) on MWCNTs is strongly dependent on pH values, dependent on ionic strength at low pH values and independent of ionic strength at high pH values. Strong surface complexation and ion exchange contribute to the adsorption of Eu(III) on MWCNTs at low pH values, whereas surface complexation and surface precipitation are the main adsorption mechanism of Eu(III) on MWCNTs. The desorption of adsorbed Eu(III) from MWCNTs by adding HCl is also studied and the recycling use of MWCNTs in the removal of Eu(III) is investigated after the desorption of Eu(III) at low pH values. The results indicate that adsorbed Eu(III) can be easily desorbed from MWCNTs at low pH values, and MWCNTs can be repeatedly used to remove Eu(III) from aqueous solutions. MWCNTs are suitable material in the preconcentration and solidification of radionuclides from large volumes of aqueous solutions in nuclear waste management. (author)

  7. Structural and luminescence properties of europium(III)-doped zirconium carbonates and silica-supported Eu3+-doped zirconium carbonate nanoparticles

    International Nuclear Information System (INIS)

    Sivestrini, S.; Riello, P.; Freris, I.; Cristofori, D.; Enrichi, F.; Benedetti, A.

    2010-01-01

    The synthesis, morphology and luminescence properties of europium(III)-doped zirconium carbonates prepared as bulk materials and as silica-supported nanoparticles with differing calcination treatments are reported. Transmission electron microscopy and X-ray diffraction analyses have, respectively, been used to study the morphology and to quantify the atomic amount of europium present in the optically active phases of the variously prepared nanomaterials. Rietveld analysis was used to quantify the constituting phases and to determinate the europium content. Silica particles with an approximate size of 30 nm were coated with 2 nm carbonate nanoparticles, prepared in situ on the surface of the silica core. Luminescence measurements revealed the role of different preparation methods and of europium-doping quantities on the optical properties observed.

  8. Characterization of the europium tetracycline complex as a biomarker for atherosclerosis

    Science.gov (United States)

    Courrol, Lilia C.; da Silva, Mônica N.; Sicchieri, Leticia B.

    2016-04-01

    Atherosclerosis is a narrowing of the arteries caused by an increase of atheromatous plaque: material formed by macrophage cells containing cholesterol and fatty acids, calcium and a variable amount of fibrous connective tissue. The elation between vulnerable plaques and cardiovascular events can be determined using plaque biomarkers. In this work, atherosclerotic plaques stained with different molar ratios of europium, in a potential plaque biomarker, europium tetracycline complex, were studied by fluorescence microscopy. The tetracycline antibiotic used was chlortetracycline. The growth of atherosclerotic plaque was followed during 60 days in New Zealand rabbits divided in two groups: an experimental group (EG), with nine animals and a control group (CG) with three animals. The animals in the EG received a diet with 1% of cholesterol and the animals of GC received a normal diet. The aortic arch of the animals with 60 days were cut in the vertical plane in 6 μm thick slices, which were mounted on glass slides and stained with hematoxylin an eosin and europium chlortetracycline complex (EuCTc). The fluorescence images were obtained exciting the EuCTc absorption band with a filter cube D (BP 355 - 425) and the emission was collected with a LP 470 suppression filter. Light intensity, detector gain and acquisition time were fixed for comparisons. The 20× magnified images were collected with 12 bit (or 4096 gray tones) resolution. The mean value of gray scale for each molar ratio of EuCTc was different, indicating that the complex interacts with the components of atherosclerotic plaque and the best molar ratio was 1.5 EuCTc. These results indicate the potential use of the EuCTc biomarker for atherosclerotic plaque characterization.

  9. Sprayed films of europium complexes toward light conversion devices

    Energy Technology Data Exchange (ETDEWEB)

    Camacho, Sabrina A.; Aoki, Pedro H.B.; Constantino, Carlos J.L.; Pires, Ana Maria, E-mail: anapires@fct.unesp.br

    2014-09-15

    Rare-earth complexes have become subject of intensive research due to the high quantum efficiency of their emission, very narrow bands, and excellent fluorescence monochromaticity. The chemical design and characterization of Eu complexes based on β-diketone ligands hexafluoroacetylacetate (hfac) and dibenzoylmetanate (dbm) is reported here. K[Eu(dbm){sub 4}] and K[Eu(hfac){sub 4}] complexes were immobilized as thin films by using the spray technique, a promising methodology for practical applications. The latter provides not only a faster layer deposition but also larger coated areas compared to conventional methods, such as layer-by-layer (LbL) and Langmuir–Blodgett (LB). The growth of the sprayed films was monitored through microbalance (QCM) and ultraviolet–visible (UV–Vis) absorption spectroscopy, which reveal a higher mass and absorbance per deposited layer of K[Eu(dbm){sub 4}] film. Micro-Raman images display a more homogeneous spatial distribution of the K[Eu(dbm){sub 4}] complex throughout the film, when compared to K[Eu(hfac){sub 4}] film. At nanometer scale, atomic force microscopy (AFM) images indicate that the roughness of the K[Eu(hfac){sub 4}] film is approximately one order of magnitude higher than that for the K[Eu(dbm){sub 4}] film, which pattern is kept at micrometer scale according to micro-Raman measurements. The photoluminescence data show that the complexes remain as pure red emitters upon spray immobilization. Besides, the quantum efficiency for the sprayed films are found equivalent to the values achieved for the powders, highlighting the potential of the films for application in light conversion devices. - Highlights: • Rare earth complexes thin films based on β-diketone ligands. • Spraying procedures to fabricate layer-by-layer (LbL) luminescent thin films. • Chemical design of Eu complexes based on hfac and dbm β-diketones ligands immobilized as sprayed films. • Pure red emitters upon spray immobilization. • Sprayed

  10. Europium(III) chelate-dyed nanoparticles as donors in a homogeneous proximity-based immunoassay for estradiol

    International Nuclear Information System (INIS)

    Kokko, Leena; Sandberg, Kaisa; Loevgren, Timo; Soukka, Tero

    2004-01-01

    Nanoparticles containing thousands of fluorescent europium(III) chelates have a very high specific activity compared to traditional lanthanide chelate labels. It can be assumed that if these particles are used in a homogeneous assay as donors, multiple chelates can excite a single acceptor in turns and the energy transfer to the acceptor is increased. The principle was employed in an immunoassay using luminescent resonance energy transfer from a long lifetime europium(III) chelate-dyed nanoparticle to a short lifetime, near-infrared fluorescent molecule. Due to energy transfer fluorescence lifetime of the sensitised emission was prolonged and fluorescence could be measured using a time-resolved detection. A competitive homogeneous immunoassay for estradiol was created using 92 nm europium(III) chelate-dyed nanoparticle coated with 17β-estradiol specific recombinant antibody Fab fragments as a donor and estradiol conjugated with near-infrared dye AlexaFluor 680 as an acceptor. The density of Fab fragments on the surface of the particle influenced the sensitivity of the immunoassay. The optimal Fab density was reached when the entire surface of the particle participated in the energy transfer, but the areas where the energy was transferred to a single acceptor, did not overlap. We were able to detect estradiol concentrations down to 70 pmol l -1 (3xSD of a standard containing 0 nmol l -1 of E2) using a 96-well platform. In this study we demonstrated that nanoparticles containing lanthanide chelates could be used as efficient donors in homogeneous assays

  11. Synthesis and characterization of La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III) and Dy(III) complexes of 2-acetylfuran-2-thenoylhydrazone

    International Nuclear Information System (INIS)

    Singh, B.; Singh, Praveen K.

    1998-01-01

    The reaction of 2-acetylfuran-2-thenoylhydrazone(afth) with Ln(III) trichlorides yields complexes of the type [Ln(afth)Cl 2 (H 2 O)(EtOH)]Cl, [Ln(III) = La, Pr, Nd, Sm, Eu, Gd, Tb and Dy]. The complexes have been characterized by molar conductance, magnetic susceptibility and TGA and DTA measurements, magnetic susceptibility and TGA and DTA measurements, FAB mass, infrared, proton NMR, electronic absorption and emission spectra. The terbium complex is found to be monomer from the FAB mass spectrum. The IR and NMR spectra suggest neutral tridentate behaviour of the Schiff base. A coordination number seven is proposed around the metal ions. Emission spectra suggest C 3v , symmetry around the metal ion with capped octahedron geometry for the europium complex. (author)

  12. Synergic extraction of europium (III) by TTA and selected carbinols or ketons in carbontetrachloride

    International Nuclear Information System (INIS)

    El-Naggar, H.A.; El-Madany, S.

    1988-01-01

    The extraction of Eu(III) by HTTA dissolved in CCl 4 has been carried from acid-perchlorate and acid-acetate solutions. Some oxygen containing solvents have been added to the chelate in extraction of the acetate complex of Eu(III). The reaction mechanisms and the equilibrium constants are calculated for the different extracted species. The data obtained are discussed in the light of the structure of carbinols and ketones used as adducts

  13. 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.

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

    International Nuclear Information System (INIS)

    Wollenberg, Anne; Raff, Johannes

    2017-01-01

    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.

  15. Determination for Enterobacter cloacae based on a europium ternary complex labeled DNA probe

    Science.gov (United States)

    He, Hui; Niu, Cheng-Gang; Zeng, Guang-Ming; Ruan, Min; Qin, Pin-Zhu; Liu, Jing

    2011-11-01

    The fast detection and accurate diagnosis of the prevalent pathogenic bacteria is very important for the treatment of disease. Nowadays, fluorescence techniques are important tools for diagnosis. A two-probe tandem DNA hybridization assay was designed for the detection of Enterobacter cloacae based on time-resolved fluorescence. In this work, the authors synthesized a novel europium ternary complex Eu(TTA) 3(5-NH 2-phen) with intense luminescence, high fluorescence quantum yield and long lifetime before. We developed a method based on this europium complex for the specific detection of original extracted DNA from E. cloacae. In the hybridization assay format, the reporter probe was labeled with Eu(TTA) 3(5-NH 2-phen) on the 5'-terminus, and the capture probe capture probe was covalent immobilized on the surface of the glutaraldehyde treated glass slides. The original extracted DNA of samples was directly used without any DNA purification and amplification. The detection was conducted by monitoring the fluorescence intensity from the glass surface after DNA hybridization. The detection limit of the DNA was 5 × 10 -10 mol L -1. The results of the present work proved that this new approach was easy to operate with high sensitivity and specificity. It could be conducted as a powerful tool for the detection of pathogen microorganisms in the environment.

  16. Study of Polymeric Luminescent Blend (PC/PMMA) Doped with Europium Complex under Gamma-Iradiation

    International Nuclear Information System (INIS)

    Parra, D. F.

    2006-01-01

    Spectroscopic properties of blends formed by bisphenol-A polycarbonate (PC) and poly(methyl methacrylate) (PMMA) doped with europium in organic complex were studied. Polymeric luminescent blends are potential materials for many applications; however, little information has been reported concerning the stability under thermal and radiation conditions. Luminescent films were synthesized from europium thenoyltrifluoroacetonate at different concentrations doped in PC/PMMA blends. Films produced of the luminescent polymer blend were irradiated in a 60 C o source. Their luminescent properties, in the solid state, as well as, the thermal oxidative resistance after gamma irradiation was investigated. These systems were characterized by elemental analysis, thermogravimetry (TGA), differential scanning calorimetry (DSC) and infrared spectroscopy (FTIR). Based on TGA data, the thermal stability of PC/PMMA:(tta)3 system is higher than the polymer blend. The DSC results indicated that those new systems are chemically stables. The emission spectra of the Eu 3 +-tta complex doped in the PC/PMMA recorded at 298 and 77 K exhibited the characteristic bands arising from the 5 D 0 →7 F J transitions (J = 0-6). The luminescence intensity decreases with increasing of precursor concentration in the doped polymer obtained by chemical reaction. This result is different from that of samples obtained by physical method in melting doping. The blend was irradiated under ionizing radiation of 60 C o source. After irradiation of the luminescent films the physical properties of luminescence, thermal and oxidative stability were evaluated.(Fapesp and Cnpq financial support)

  17. 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)

  18. Ligand effect on the performance of organic light-emitting diodes based on europium complexes

    International Nuclear Information System (INIS)

    Fang Junfeng; You Han; Gao Jia; Lu Wu; Ma Dongge

    2007-01-01

    A series of europium complexes were synthesized and their electroluminescent (EL) characteristics were studied. It was found by comparison that the different substituted groups, such as methyl, chlorine, and nitryl, on ligand 1,10-phenanthroline affect significantly the EL performance of devices based on these complexes. The more methyl-substituted groups on ligand 1,10-phenanthroline led to higher device efficiency. A chlorine-substituted group showed the approximate EL performance as two methyl-substituted groups, whereas a nitryl substituent reduced significantly the EL luminous efficiency. However, β-diketonate ligand TTA and DBM exhibited similar EL performance. The improved EL luminous efficiency by proper substituted groups on the 1,10-phenanthroline was attributed to the reduction of the energy loss caused by light hydrogen atom vibration, as well as concentration quenching caused by intermolecular interaction, and the match of energy level between the ligand and Eu 3+

  19. Solvent extraction of lanthanum (III), europium (III), and lutetium (III) with 5,7-dichloro-8-quinolinol into chloroform in the absence and presence of tetrabutylammonium ions or trioctylphosphine oxide

    International Nuclear Information System (INIS)

    Noro, Junji; Sekine, Tatsuya.

    1993-01-01

    The solvent extractions of lanthanum(III), europium(III), and lutetium(III) (M 3+ ) in 0.1 moldm -3 sodium nitrate solutions with 5,7-dichloro-8-quinolinol (HA) into chloroform were studied in both the absence and presence of tetrabutylammonium ions (tba + ) or trioctylphosphine oxide (TOPO). In the absence of tba + or TOPO, the extracted species were the MA 3 and MA H A (self-adduct), though MA 4 - tba + was found when tba + was added; MA 3 TOPO and MA 3 (TOPO) 2 were found when TOPO was added in addition to the above mentioned two species. The anionic complex or TOPO adducts greatly enhanced the extraction. The data were statistically analyzed and the equilibrium constants for the extraction of these species, as well as the constants for the association of the HA, the A - tba + , or the TOPO on the MA 3 in the organic phase, were determined. The extraction of the MA 3 is better in the order LaA 3 3 3 . Although the values of the association constant of the HA or the TOPO on the MA 3 are rather similar for the three metal chelates, the constants for A - tba + are larger in the same order as mentioned above. Thus, the separation of these three metal ions by solvent extraction with this chelating extractant is not much affected by the addition of TOPO, but is greatly improved by the addition of tba + . (author)

  20. Selective extraction of americium(III) over europium(III) ions with pyridylpyrazole ligands. Structure-property relationships

    Energy Technology Data Exchange (ETDEWEB)

    Su, Dongping; Liu, Ying; Li, Shimeng; Ding, Songdong; Jin, Yongdong; Wang, Zhipeng; Hu, Xiaoyang; Zhang, Lirong [Department of chemistry, Sichuan University, Chengdu (China)

    2017-01-18

    To clarify the structure-property relationships of pyridylpyrazole ligands and provide guidance for the design of new and more efficient ligands for the selective extraction of actinides over lanthanides, a series of alkyl-substituted pyridylpyrazole ligands with different branched chains at different positions of the pyrazole ring were synthesized. Extraction experiments showed that the pyridylpyrazole ligands exhibited good selective extraction abilities for Am{sup III} ions, and the steric effects of the branched chain had a significant impact on the distribution ratios of Am{sup III} and Eu{sup III} ions as well as the separation factor. Moreover, both slope analyses and UV/Vis spectrometry titrations indicated the formation of a 1:1 complex of 2-(1-octyl-1H-pyrazol-3-yl)pyridine (C8-PypzH) with Eu{sup III} ions. The stability constant (log K) for this complex obtained from the UV/Vis titration was 4.45 ± 0.04. Single crystals of the complexes of 3-(2-pyridyl)pyrazole (PypzH) with Eu(NO{sub 3}){sub 3} and Sm(NO{sub 3}){sub 3} were obtained; PypzH acts as a bidentate ligand in the crystal structures, and the N atom with a bound H atom did not participate in the coordination. In general, this study revealed some interesting findings on the effects of the alkyl-chain structure and the special complexation between pyridylpyrazole ligands and Ln{sup III} ions. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Reducing the photo-bleaching effect of a new europium complex embedded in styrene butadiene copolymer

    Science.gov (United States)

    Jiménez, G. Lesly; Reyes-Rodríguez, J. L.; Padilla, Isela; Alarcón-Flores, G.; Falcony, C.

    2018-02-01

    A highly luminescent europium complex obtained with two different ligands, succinimide (SI) and 2-thenoyltrifluoroacetone (TTA) , was synthetized with different TTA concentrations. The photoluminescence (PL) emission from these materials corresponds to the characteristic inter-electronic energy level transitions of the Eu3+ ions. However, the excitation spectrum is strongly dependent on the presence of TTA, having an optimum response when 0.75 mmol of this compound is added to the EuL3(H2O)3 complex. The quantum yield obtained by these powders were around 72 % ± 1.7 % indicating an optimum sensitization of these complex. The EuL3 TTA complex with the best PL properties was embedded in a styrene butadiene copolymer (SBC) film, produced by the drop casting method, obtaining similar PL behavior at different concentrations, the highest intensity was observed at 1.2% (w/v) of EuL3 TTA complex and the quantum yield of these composite films was 60.5 % ± 2 % . These films were exposed to continuous UV irradiation and after 141 h no photo-bleaching effect was observed in contrast with the EuL3 TTA complex that exhibited a noticeable photoluminescence intensity degradation at much shorter exposure times. Both the Eu-complexes and the composite films were characterized by FT-IR, XRD, SEM and fluorescence spectroscopy.

  2. Spectroscopic studies on the interaction of europium(III) and curium(III) with components of the human mucosa

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, Claudia; Barkleit, Astrid [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Chemistry of the F-Elements

    2016-07-01

    To evaluate the health risks of lanthanides (Ln) and radiotoxic actinides (An) in case of ingestion accidents etc., investigations into the chemical reactions of these metals in the human gastrointestinal tract are necessary. Our previous study revealed that mucin, an important part of the protective mucosa layer in the digestive system, shows a strong interaction with Eu(III). Based on these results, the present study focuses on the components of this glycoprotein and identified N-acetylneuraminic acid (NANA) as the dominant binding carbohydrate of mucin. TRLFS measurements suggest the formation of a 1: 1 complex with log β of 3.2 ± 0.1 for Eu(III) and 3.3 ± 0.1 for Cm(III), respectively.

  3. Detection of Sugars via Chirality Induced in Europium(III) Compounds

    Czech Academy of Sciences Publication Activity Database

    Wu, Tao; Průša, Jiří; Kessler, Jiří; Dračínský, Martin; Valenta, J.; Bouř, Petr

    2016-01-01

    Roč. 88, č. 17 (2016), s. 8878-8885 ISSN 0003-2700 R&D Projects: GA ČR(CZ) GA16-05935S; GA ČR(CZ) GJ16-08764Y; GA ČR GA15-11223S; GA ČR GA15-09072S Institutional support: RVO:61388963 Keywords : Raman optical activity * molecular dynamics simulations * D-3 lanthanide(III) complexes Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 6.320, year: 2016

  4. Computational Investigation on the Spectroscopic Properties of Thiophene Based Europium β-Diketonate Complexes.

    Science.gov (United States)

    Greco, Claudio; Moro, Giorgio; Bertini, Luca; Biczysko, Malgorzata; Barone, Vincenzo; Cosentino, Ugo

    2014-02-11

    The adiabatic transition energies from the lowest triplet states of four Europium tris β-diketonate/phenantroline complexes have been determined in vacuo and in dicholomethane solution by the ΔSCF approach at the density functional theory level, using the PBE1PBE and the CAM-B3LYP hybrid functionals. The calculated adiabatic transition energies have been compared with the experimental 0-0 transitions of each complex determined from phosphorescence spectra of the corresponding Gd(3+) complexes and followed by direct comparison between simulated and experimental spectra line shapes. For compound 1, the Eu(TTA)3Phen system, triplet states other than the lowest one and conformational isomers other than the one present in the crystallographic structure have been considered. In the crystallographic structure, this compound presents three quasi-degenerate low energy triplet states, differing for the TTA ligand where the two unpaired electrons are localized and showing close adiabatic transition energies. For compound 1, the lowest triplet states of the four investigated conformational isomers show similar characteristics and close adiabatic transition energies. On the basis of these results, an investigation of compounds 2-4 (Eu(Br-TTA)3Phen, Eu(DTDK)3Phen, and Eu(MeT-TTA)3) has been performed by considering only the isomer present in the crystallographic structure and only the lowest triplet state of each compound. For compounds 1-3, the energies of the lowest triplet states calculated by both functionals in solution including zero-point energy corrections well reproduce the experimental trends as well as the values of the adiabatic transition energies: CAM-B3LYP, the best performing functional, provides energies of the lowest triplet state with deviations from experiments lower than 1200 cm(-1). Also, the calculated vibrationally resolved phosphorescence spectra and UV-vis absorptions well reproduce the main features of their experimental counterparts. Significant

  5. Characterization of an azo-calix[4]arene-based optical sensor for Europium (III) ions

    International Nuclear Information System (INIS)

    Echabaane, M.; Rouis, A.; Bonnamour, I.; Ouada, H. Ben

    2012-01-01

    Selective and sensitive optical sensor membranes (optodes) were elaborated to detect cations in aqueous solutions. The sensing films are based on chromogenic calix[4]arene derivatives. The optode membranes were studied using UV/Vis absorption spectroscopy measurements. The sensitivity of the optode has been tested for Pb 2+ , Cd 2+ , Mg 2+ and Eu 3+ ions at pH 6.8. The results showed a good selectivity response towards Eu 3+ . Low selectivity coefficients were observed for Cd 2+ and Mg 2+ where Pb 2+ can be considered as interfering ions. The characteristics of this optode such as response time, regeneration, reproducibility and lifetime are discussed. - Highlights: ► We report optical sensing studies of chromogenic calixarene derivatives. ► We investigate optical interaction between azo-calix[4]arene and Eu 3+ . ► We study sensitivity and selectivity of optode films. ► We describe characteristics of optode films for determination of europium traces.

  6. Solvation and complexation study by fluorescence spectroscopy of Eu(III) and Cm(III) ions in octanol solution and at the interface with water

    International Nuclear Information System (INIS)

    Vu, T.H.

    2008-01-01

    Polydentate N-donors ligands like bis-triazine-pyridine (BTP) and bis-triazine-bis-pyridine (BTBP) can selectively extract minor actinides (III) from lanthanides (III) ions and therefore have been studied in the field of nuclear waste reprocessing. The aim of the researches carried out during this thesis is a better description of this family in biphasic systems: speciation in the organic phase and around the interfacial area. After an exhaustive description of the solvation of europium(III) cation in mixed solutions n-octanol water with TRLIF spectrometry, the complexation with nitrogen ligands iPr-BTP, C5-BTBP and CyMe4-BTBP has been studied by TRLIF and ESI-MS techniques. For each compound, the inner sphere of europium has been described and the conditional stability constants determined. The composition of the organic medium, and particularly the hydration degree of n-octanol, has an impact on the nature and the ratio of species 'cation - counter ion - ligand - water'. With high water content (representative of extraction systems), the complexes observed with Cm(III) and Eu(III) have the same stoichiometry but the affinity towards the curium cation is higher and consistent to separation factors measured with biphasic systems. The method TIRF (total internal reflection fluorescence) was retained to study the behaviour of europium(III) inside the interfacial area. Fluorescence spectra of europium have been obtained but side signals and the high depth resolution of detection lead to difficulty in obtaining the signal of interfacial europium alone. The selected technique remains promising but some improvements need to be implemented for forthcoming measurement at liquid/liquid interface. (author) [fr

  7. NMR and luminescence spectroscopy study of formation of mixed β-diketonate europium complexes

    International Nuclear Information System (INIS)

    Kavun, V.Ya.; Kalinovskaya, I.V.; Karasev, V.E.; Chernyshov, B.N.; Steblevskaya, N.I.

    1987-01-01

    Methods of NMR ('H, 19 F) and luminescent spectroscopy were applied to study ligand substitution in Eu(β-dik) 3 phen-CDCl 3 -(β-dik)' systems, where β-dik-acetylacetone (AA) and hexafluoroacetyl-acetone (HFAA), phen-1.10-phenathroline at different mole ratio (m) of competing ligands (m=AA/HFAA). Formation of mixed Eu(AA) 2 (HFAA)phen and Eu(AA)(HFAA) 2 phen complexes is proved; calculation of the stark structure of 5 D 0 - 7 F j (j=0,1,2) transitions in low-temperature luminescence spectra is conducted for these complexes. It is stated that at minimum HFAA concentration in the solution the latter replaces AA from europium coordination sphere. It is shown that depending on the value in substitution of acidoligands proceeds successfully by the equations Eu(AA) 3 phen+(NHFAA) n → Eu(AA) 3-n → (HFAA) n phen+(NAA) n ; (n=1,2,3)

  8. Fluorometric determination of samarium and europium in rare earth minerals with. beta. -diketoneternary complex

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H; Hiraki, K; Nishikawa, Y [Kinki Univ., Higashi-Osaka, Osaka (Japan). Faculty of Science and Technology

    1981-07-01

    This communication reported the optimum conditions for the fluorometric determination of these ions, and the method was adopted in the simultaneous determination of samarium and europium in xenotime and monazite minerals. From the experimental results on the effect of diverse ions and the extraction pH of the aqueous phase, it became clear that TTA-TOPO hexane method was the best system for the determination of samarium and europium because of the highest fluorescence sensitivity of the ternary complex, and also because the lower extraction pH eliminated the effect of diverse ions. Moreover, the very high detection limit (2 ppb) of Sm was achieved by the use of a red sensitive photomultiplier. Which was used at 644 nm, and that of Eu (0.02 ppb) at 614 nm. The procedure was established as follows: The rare earth minerals (xenotime, monazite) sample was treated with hot conc. H/sub 2/SO/sub 4/ and twice precipitated with 0.5 mol dm/sup -3/ oxalic acid (pH was adjusted to 2.0 -- 2.2). Then the precipitate was filtered and ignited to give the rare earth oxide. Fifty milligrams of the oxide was dissolved in HCl and diluted with water in order to obtain the solution containing 5 ..mu..g cm/sup -3/ rare earth oxide. An aliquot of the solution ((1.0 -- 3.0) cm/sup 3/) was adjusted to pH 5.5 with sodium acetate and shaken with 1 x 10/sup -4/ mol dm/sup -3/ TTA- 2 x 10/sup -2/ mol dm/sup -3/ TOPO hexane solution. Then the fluorescence intensity of the organic layer was measured at 644 nm for Sm and 614 nm for Eu. In this procedure, the recovery of Sm and Eu was found to be about 96%. Xenotime contained 0.70% of Sm and 0.004% of Eu, and monazite contained 1.84% of Sm and 0.003% of Eu.

  9. Electroplex emission from a layer of a mixture of a europium complex and tris(8-quinolinolato) aluminum

    Science.gov (United States)

    Cao, Hong; Gao, Xicun; Huang, Chun-Hui

    2000-07-01

    With a europium complex, tris(α-thenoyltrifluoroacetonato) bis(triphenylphosphine oxide) europium (Eu(TTA) 3(TPPO) 2), as the light-emitting layer, N, N'-diphenyl- N, N'-di( m-tolyl)-benzidine (TPD) as the hole transport layer and tris(8-quinolinolato) aluminum (ALQ) as the electron transport layer, the triple-layer electroluminescent (EL) device emits red light characteristic of Eu 3+ emission. However, as the mixture of Eu(TTA) 3(TPPO) 2 and ALQ is co-evaporated as the light-emitting layer to form a bilayer EL device, a new wide-banded emission peaked at c. 640 nm was obtained. This emission is neither from ALQ nor from the europium complex. The photoluminescence (PL) of the thin film on quartz substrate evaporated from one mixed solid powder of Eu(TTA) 3(TPPO) 2 and ALQ is composed of distinct PL emissions of Eu(TTA) 3(TPPO) 2 and ALQ, denying an exciplex formation mechanism. It is impossible to form a host-guest system. We propose that the EL emission peaked at c. 640 nm is from an electroplex route: a transition between the lowest unoccupied molecular orbital (LUMO) of Eu(TTA) 3(TPPO) 2 and the highest occupied molecular orbital (HOMO) of ALQ.

  10. Study on photophysical properties of Eu(III) complexes with aromatic β-diketones – Role of charge transfer states in the energy migration

    Energy Technology Data Exchange (ETDEWEB)

    Räsänen, Markus, E-mail: mpvras@utu.fi [Department of Chemistry, University of Turku, FIN-20014 Turku (Finland); Takalo, Harri [DHR Finland Oy, Innotrac Diagnostics, Biolinja 12, FIN-20750 Turku (Finland); Rosenberg, Jaana; Mäkelä, Joonas [Department of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku (Finland); Haapakka, Keijo; Kankare, Jouko [Department of Chemistry, University of Turku, FIN-20014 Turku (Finland)

    2014-02-15

    We synthesized a set of aromatic β-diketones and measured the photophysical properties of their europium(III) complexes. According to these photophysical properties, the europium complexes can be divided into two groups: the complexes with or without the freely rotating amino-group (FRAG). On the basis of the experimental results, it can be concluded that in the FRAG complexes, the ligand-centered excitation energy is most probably transferred from a ligand to a coordinated europium via the intraligand charge transfer (ILCT) state. The temperature dependency of the lifetimes of the emissive {sup 5}D{sub 0} state revealed that in the FRAG complexes, the energy of the emissive {sup 5}D{sub 0} state is back-transferred to the ligand-to-metal charge transfer (LMCT) state and in the non-FRAG complexes, to the triplet state of the ligand. The most efficient complex synthesized was the europium complex of carbazole derivative L{sup 6} with the quantum yield of 47% and molar absorption coefficient of 70,400 M{sup −1}cm{sup −1}. -- Highlights: • We synthesized a set of substituted aromatic β-diketones and their Eu(III) complexes. • We measured the photophysical properties of these Eu(III) complexes. • Carbazole derivative of β-diketone forms the brightest Eu(III) complex. • The Jablonski diagrams proposed for the luminescence of these complexes.

  11. Determination of the stability constants of lanthanum, praseodymium, europium, erbium and lutetium complexes with chloride ions

    International Nuclear Information System (INIS)

    Fernandez R, E.

    2008-01-01

    The stability constants of La 3+ , Pr 3+ , Eu 3+ , Er 3+ and Lu 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 2+ ) or two chemical species (LnCl 2+ and LnCl 2 + ). The Specific Ion Interaction Theory was applied to the values of log β I Ln , Cl and the first stability constants at zero ionic strength were calculated by extrapolation. The same theory could not be applied to the log β I Ln , 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 β I Ln , CI , log β I Ln , 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 β I Ln , 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. Solvent extraction of europium(III) with benzoylacetone and benzoyltrifluoroacetone into carbon tetrachloride in the absence and presence of tetrabutylammonium ions

    International Nuclear Information System (INIS)

    Noro, Junji; Sekine, Tatsuya.

    1992-01-01

    The solvent extraction of europium (III) in 0.1 mol dm -3 sodium nitrate solutions with benzoylacetone (Hbza) or benzoyltrifluoroacetone (Hbfa) in carbon tetrachloride was measured in the absence and presence or tetrabutylammonium ions (tba + ). Although extraction with Hbfa occurred at lower pH than with Hbza, the extraction measured as a function of the β-diketonate ion concentration in the aqueous phase was rather similar. It was also found that extraction with Hbfa was greatly enhanced by the addition of tba + , the effect, however, was negligible with Hbza. The data were analyzed from the stand point that the neutral metal chelate, Eu(bfa) 3 , was extracted into the organic phase and associated with ion-pairs of the reagents, bfa - tba + , in this phase. It was also found that though extraction of ion-pairs of bfa - tba + occurred, that of bza - tba + was negligible. Thus, the reason for the negligible extraction of the ternary complex, Eu (bza) 4 - tba + , was explained in terms of the negligible extraction of the bza - tba + , which might associate with Eu(bza) 3 in the organic phase. (author)

  13. Polarographic determination of stability constants of Eu(III) complexes with acrylic acid and crotonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Rao, A L.J.; Makhan, S [Punjabi Univ., Patiala (India). Dept. of Chemistry

    1979-07-01

    Compositions and formation constants of Eu(III) complexes with acrylic acid and crotonic acid have been studied polarographically. The reductions are reversible and diffusion-controlled. The plot of Esub(1/2) versus -log Csub(x) is linear in the case of Eu(III)-acrylic acid system. The change in number of ligands bound to europium during reduction was found to be approximately equal to 1 and ratio of dissociation constants of Eu(III) and Eu(II) was found to be 40.76 x 10sup(-2). In the case of Eu(III)-crotonic acid system, composition and formation constants have been calculated by the method of Deford and Hume. Crotonic acid forms two complex species with europium (..beta../sub 1/, 60; ..beta../sub 2/, 4.2x10sup(+2)). The percentage distribution of various complex species as a function of ligand concentration has been calculated in the case of Eu(III)-crotonic acid system. A polarographic method for the determination of micro amounts of Eu(III) in the presence of diverse ions has been developed. Under optimum conditions Eu(III) in the concentration range 4x10sup(-4)-2x10sup(-3)M can be successfully determined in various mixtures.

  14. Polarographic determination of stability constants of Eu(III) complexes with acrylic and crotonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Rao, A L.J.; Singh, Makhan [Punjabi Univ., Patiala (India). Dept. of Chemistry

    1979-07-01

    Compositions and formation constants of Eu(III) complexes with acrylic acid and crotonic acid have been studied polarographically. The reductions are reversible and diffusion-controlled. The plot of Esub(1/2) versus--log Csub(x) is linear in the case of Eu(III)-acrylic acid system. The change in number of ligands bound to europium during reduction was found to be approximately 1 and ratio of dissociation constants of Eu(III) and Eu(II) was found to be 40.76X10sup(-2). In the case of Eu(III)-crotonic acid system, composition and formation constants have been calculated by the method of Deford and Hume. Crotonic acid forms two complex species with europium (..beta../sub 1/,60; ..beta../sub 2/, 4.2x10sup(+2)). The percentage distribution of various complex species as a function of ligand concentration has been calculated in the case of Eu(III)-crotonic acid system. A polarographic method for the determination of micro amounts of Eu(III) in the presence of diverse ions has been developed. Under optimum conditions Eu(III) in the concentration range 4x19sup(-4)-2x10sup(-2)M can be successfully determined in various mixtures.

  15. Organometallic neptunium(III) complexes.

    Science.gov (United States)

    Dutkiewicz, Michał S; Farnaby, Joy H; Apostolidis, Christos; Colineau, Eric; Walter, Olaf; Magnani, Nicola; Gardiner, Michael G; Love, Jason B; Kaltsoyannis, Nikolas; Caciuffo, Roberto; Arnold, Polly L

    2016-08-01

    Studies of transuranic organometallic complexes provide a particularly valuable insight into covalent contributions to the metal-ligand bonding, in which the subtle differences between the transuranium actinide ions and their lighter lanthanide counterparts are of fundamental importance for the effective remediation of nuclear waste. Unlike the organometallic chemistry of uranium, which has focused strongly on U(III) and has seen some spectacular advances, that of the transuranics is significantly technically more challenging and has remained dormant. In the case of neptunium, it is limited mainly to Np(IV). Here we report the synthesis of three new Np(III) organometallic compounds and the characterization of their molecular and electronic structures. These studies suggest that Np(III) complexes could act as single-molecule magnets, and that the lower oxidation state of Np(II) is chemically accessible. In comparison with lanthanide analogues, significant d- and f-electron contributions to key Np(III) orbitals are observed, which shows that fundamental neptunium organometallic chemistry can provide new insights into the behaviour of f-elements.

  16. Investigation of the separation of americium(III) and europium(III) by high-speed countercurrent chromatography

    International Nuclear Information System (INIS)

    Wu, J.F.; Jin, Y.R.; Xu, Q.C.; Wang, S.L.; Zhang, L.X.

    2005-01-01

    The long-lived actinides are the important elements in the radioactive waste ;disposal. Because the ions semi diameter and chemical properties of trivalent actinides(III) and trivalent lanthanides(III) are very similar, the separation between them is very difficult. Yang Yu-Sheng put forward the actinides(III) are softer acid than the lanthanides(III), so the actinides(III) are more easily extracted by the soft extractant contain sulfur or nitrogen than the lanthanides(III). Some research have been done on the separation between actinides(III) and lanthanides(III) using the extractants contain sulfur or nitrogen. The results show that satisfactory separation efficiency was gained. Countercurrent Chromatography (CCC) have many specific advantages, such as free from solid support, permit large sample volume and high flow rate, which is useful in the preconcentration of inorganic solute and inorganic preparation. Some studies were done on the separation of lanthanides or-other inorganic elements by HSCCC, the high-purity reagents prepared by HSCCC or CPC turned out to be successful. In present paper, the investigation of separation between Americium (III) and Euricium (III) by High-Speed Countercurrent Chromatography (HSCCC) were made. The extractant used in the work was prepared by ourselves, which is of the soft extractant contrain sulfur. The effects of separation condition on the separation efficiency of Am and Eu by HSCCC were investigated using dichlorophenyl dithiophosphinic acid in xylene as the stationary phase and 0.1 mol/L NaClO4 as mobile phase, respectively. The results show that mutual separation between Am and Eu can be accomplished. The separation factor increases with the increasing of the concentration of extractant and the pH value of the mobile phase, further more, minishing the flow rate of the mobile phase can also improves the separation efficiency between Am and Eu. The nearly base separation was gained when the flow rate is 0.35 ml/min, the

  17. Organometallic neptunium(III) complexes

    Science.gov (United States)

    Dutkiewicz, Michał S.; Farnaby, Joy H.; Apostolidis, Christos; Colineau, Eric; Walter, Olaf; Magnani, Nicola; Gardiner, Michael G.; Love, Jason B.; Kaltsoyannis, Nikolas; Caciuffo, Roberto; Arnold, Polly L.

    2016-08-01

    Studies of transuranic organometallic complexes provide a particularly valuable insight into covalent contributions to the metal-ligand bonding, in which the subtle differences between the transuranium actinide ions and their lighter lanthanide counterparts are of fundamental importance for the effective remediation of nuclear waste. Unlike the organometallic chemistry of uranium, which has focused strongly on UIII and has seen some spectacular advances, that of the transuranics is significantly technically more challenging and has remained dormant. In the case of neptunium, it is limited mainly to NpIV. Here we report the synthesis of three new NpIII organometallic compounds and the characterization of their molecular and electronic structures. These studies suggest that NpIII complexes could act as single-molecule magnets, and that the lower oxidation state of NpII is chemically accessible. In comparison with lanthanide analogues, significant d- and f-electron contributions to key NpIII orbitals are observed, which shows that fundamental neptunium organometallic chemistry can provide new insights into the behaviour of f-elements.

  18. 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.

  19. 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)

  20. Self-assembly of a helical zinc-europium complex: speciation in aqueous solution and luminescence

    Directory of Open Access Journals (Sweden)

    Emmanuel eDeiters

    2013-09-01

    Full Text Available Two new tridentate(NNO-bidentate(NN compartmental ligands, HL5 and HL6, are synthesized from pyridine and benzimidazole synthons. They react in aqueous solution under physiological conditions with ZnII, LnIII, or a mixture thereof, to yield complexes of different stoichiometries, 1:3, 2:2, 2:3, 1:1:3, the speciation of which is established by UV-visible titrations and ESI mass spectrometry. Photophysical studies of the EuIII-containing solutions in Tris-HCl 0.1 M (pH = 7.4 show that lanthanide luminescence arises from a unique N6O3 coordination site with pseudo D3 symmetry. Relevant parameters such as crystal field splitting, lifetime, radiative lifetime and intrinsic quantum yield perfectly match those reported for dinuclear 4f-4f helicates in which the EuIII ion has the same coordination environment.

  1. Investigations of gamma irradiation on the properties of luminescent films of polycarbonate(PC) matrix doped with europium complex [Eu(tta)3(H2O)2

    International Nuclear Information System (INIS)

    Forster, Pedro L.; Lugao, Ademar B.; Martins, Natalia A.; Egute, Nayara S.; Parra, Duclerc F.; Brito, Hermi F.

    2009-01-01

    Luminescent lanthanide complexes have attracted much recent interest for their application as luminescent materials. The combination of unique spectroscopic properties from rare earth complexes associated to physical and chemical intrinsic properties of polymers became more attractive in the last years. A number of advantages of these substances have been reported or realized over the much studied conjugated polymers and nonlanthanide. Luminescent films composed by diaquatris(thenoyltrifluoroacetonate)europium(III) complex [Eu(tta) 3 (H 2 O) 2 ] doped into a polycarbonate (PC) matrix were prepared and irradiated at gamma radiation with 5, 10, and 20 kGy. The PC polymer was doped with 1% (w/w) of the Eu 3+ complex. The thermal properties was investigated by utilization of differential scanning calorimeter (DSC) changes in thermal stability was observed due to the addition of doping agent into the polycarbonate matrix. Changes in photophysical properties due of gamma radiation was observed by emission, excitation spectra and fourier transformed infrared spectra (FTIR). Based on the emission spectra of PC:1% Eu(tta)3 film were observed the characteristic bands arising from the 5 D 0 7 F J transitions of Eu 3+ ion (J=0-4), indicating the ability to obtain the luminescence films. (author)

  2. Probing phosphate ion via the europium(III)-modulated fluorescence of gold nanoclusters

    International Nuclear Information System (INIS)

    Ding, Shou-Nian; Li, Chun-Mei; Gao, Bu-Hong; Kargbo, Osman; Zhou, Chan; Chen, Xi; Wan, Neng

    2014-01-01

    Fluorescent gold nanoclusters (Au-NCs) were synthesized by a one-pot method using 11-mercaptoundecanoic acid as a reducing and capping reagent. It is found that the red fluorescence of the Au-NCs is quenched by the introduction of Eu(III) at pH 7.0, but that fluorescence is restored on addition of phosphate. The Au-NCs were investigated by transmission electron microscopy and fluorescence photographs. The effect of pH on fluorescence was studied in the range from pH 6 to 10 and is found to be strong. Based on these findings, we have developed an assay for phosphate. Ions such as citrate, Fe(CN) 6 3− , SO 4 2− , S 2 O 8 2− , Cl − , HS − , Br − , AcO − , NO 2 − , SCN − , ClO 4 − , HCO 3 − , NO 3 − , Cd 2+ , Ba 2+ , Zn 2+ , Mg 2+ , and glutamate do not interfere, but ascorbate and Fe 3+ can quench Au-NCs fluorescence. The fluorescent nanocluster probe responds to phosphate in the range from 0.18 to 250 μM, and the detection limit is 180 nM. The probe also responds to pyrophosphate and ATP. (author)

  3. Determination of ATP as a fluorescence probe with europium(III)-doxycycline.

    Science.gov (United States)

    Hou, Faju; Wang, Xiaolei; Jiang, Chongqiu

    2005-03-01

    A new spectrofluorimetric method has been developed for the determination of adenosine disodium triphosphate (ATP). We studied the interactions between the doxycycline (DC)-Eu3+ complex and adenosine disodium triphosphate (ATP) by using UV-visible absorption and fluorescence spectra. Using doxycycline (DC)-Eu3+ as a fluorescence probe, under the optimum conditions, ATP could remarkably enhance the fluorescence intensity of the DC-Eu3+ complex at lambda = 612 nm. The enhanced fluorescence intensity of the Eu3+ ion was in proportion to the concentration of ATP. The optimum conditions for the determination of ATP were also investigated. The linear ranges for ATP were 1.00 x 10(-7) - 2.00 x 10(-6) mol L(-1) with detection limits of 4.07 x 10(-8) mol L(-1). This method is simple, practical and relatively free of interference from coexisting substances, and can be successfully applied to the determination of ATP in samples. The mechanism of fluorescence enhancement between the doxycycline (DC)-Eu3+ complex and ATP was also studied.

  4. Highly photoluminescent europium tetraphenylimidodiphosphinate ternary complexes with heteroaromatic co-ligands. Solution and solid state studies

    Energy Technology Data Exchange (ETDEWEB)

    Pietraszkiewicz, Marek, E-mail: mpietraszkiewicz@ichf.edu.pl [Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland); Pietraszkiewicz, Oksana; Karpiuk, Jerzy; Majka, Alina [Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland); Dutkiewicz, Grzegorz; Borowiak, Teresa [Adam Mickiewicz University, Faculty of Chemistry, Department of Crystallography, Grunwaldzka 6, 60-780 Poznań (Poland); Kaczmarek, Anna M. [L3–Luminescent Lanthanide Lab, f-element coordination chemistry, Ghent University, Department of Inorganic and Physical Chemistry, Krijgslaan 281, Building S3, 9000 Gent (Belgium); Van Deun, Rik, E-mail: rik.vandeun@ugent.be [L3–Luminescent Lanthanide Lab, f-element coordination chemistry, Ghent University, Department of Inorganic and Physical Chemistry, Krijgslaan 281, Building S3, 9000 Gent (Belgium)

    2016-02-15

    Tetraphenylimidodiphosphinate (tpip) forms neutral 3:1 complexes with lanthanide ions. These complexes can accommodate one ancillary planar heterocyclic ligand to complement their coordination sphere of Eu{sup 3+} to coordination number 8. Several co-ligands were tested to form new complexes: 1,10-phenanthroline, bathophenanthroline, 2,4,6-tris(2-pyridyl)-1,3,5-triazine, dipyrido[3,2-f:2′,3′-h]quinoxaline and 2,2′:6′,2′′-terpyridine. The addition of heterocyclic N,N-bidentate co-ligands to the coordination sphere results in a dramatic (by a factor of 45–50) luminescence enhancement of the parent Eu(tpip){sub 3}. The solid-state measurements confirmed that the ancillary ligands strongly increased the photoluminescence quantum yield (PLQY) of the investigated complexes. - Highlights: • We have disovered highly photoluminescent ternary Eu(III) complexes. • They consist of Eu(III) tetraphenylimidodiphosphinate, and planar heterocyclic ligands. • The increase in photoluminescence quantum yields in solution is enhanced up to 50 times in solution. • The solid-state photoluminescence exceeds 80% at room temperature.

  5. Highly photoluminescent europium tetraphenylimidodiphosphinate ternary complexes with heteroaromatic co-ligands. Solution and solid state studies

    International Nuclear Information System (INIS)

    Pietraszkiewicz, Marek; Pietraszkiewicz, Oksana; Karpiuk, Jerzy; Majka, Alina; Dutkiewicz, Grzegorz; Borowiak, Teresa; Kaczmarek, Anna M.; Van Deun, Rik

    2016-01-01

    Tetraphenylimidodiphosphinate (tpip) forms neutral 3:1 complexes with lanthanide ions. These complexes can accommodate one ancillary planar heterocyclic ligand to complement their coordination sphere of Eu 3+ to coordination number 8. Several co-ligands were tested to form new complexes: 1,10-phenanthroline, bathophenanthroline, 2,4,6-tris(2-pyridyl)-1,3,5-triazine, dipyrido[3,2-f:2′,3′-h]quinoxaline and 2,2′:6′,2′′-terpyridine. The addition of heterocyclic N,N-bidentate co-ligands to the coordination sphere results in a dramatic (by a factor of 45–50) luminescence enhancement of the parent Eu(tpip) 3 . The solid-state measurements confirmed that the ancillary ligands strongly increased the photoluminescence quantum yield (PLQY) of the investigated complexes. - Highlights: • We have disovered highly photoluminescent ternary Eu(III) complexes. • They consist of Eu(III) tetraphenylimidodiphosphinate, and planar heterocyclic ligands. • The increase in photoluminescence quantum yields in solution is enhanced up to 50 times in solution. • The solid-state photoluminescence exceeds 80% at room temperature.

  6. Spectrochemical study of europium and neodymium complexes with 3-(3'-trifluoromethoxy-2',2',3',3'-tetrafluoropropionyl)camphor and bisheterocycles

    International Nuclear Information System (INIS)

    Khomenko, V.S.; Pavich, T.A.; Lozonskij, M.O.; Fialkov, Yu.A.; AN Ukrainskoj SSR, Kiev. Inst. Organicheskoj Khimii)

    1987-01-01

    Methods of mass-spectrometry, luminescent specroscopy and thermogravimetry are used to study decomposition ways, structure and volatility of mixed europium and neodymium complexes with fluorated organic ligands and bisheterocycles. It is shown that complexes containing an oxygen atom in a fluorated ligand elimination of difluorophosgene and tetrafluoroethylene molecules takes place. The addition of a bisheterocyclic ligand to a triligand complex makes the averaged bond in the complex more covalent and increase its volatility

  7. On the complexing of phosphoric acid vinyl esters with praseodymium (3) and europium (3) nitrates in acetonitrile

    International Nuclear Information System (INIS)

    Goryushko, A.G.; Gololobov, Yu.G.; Boldeskul, A.E.; Oganesyan, A.S.; Yartsev, V.G.

    1990-01-01

    By the methods of electron, IR and PMR spectroscopy interaction of vinyl esters of phosphoric acid with praseodymium (3) and europium (3) nitrates in acetonitrile solutions has been studied. It is shown that the character of metal-ligand interaction is determined by chemical nature of the ligands: for a compound of ionic structure partially covalent bond is formed, and for a compound of betaine structure the interaction has mainly dipole character. Addition of molecule with betaine structure to praseodymium nitrate causes a change in geometry of Pr 3+ close surrounding and increase in its coordination number. The possibility of formation of the complex with metal-ligand ratio equal to 1:3 is shown

  8. Efficient red organic electroluminescent devices based on trivalent europium complex obtained by designing the device structure with stepwise energy levels

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Liang; Jiang, Yunlong; Cui, Rongzhen; Li, Yanan; Zhao, Xuesen; Deng, Ruiping; Zhang, Hongjie, E-mail: hongjie@ciac.ac.cn

    2016-02-15

    In this study, we aim to further enhance the electroluminescence (EL) performances of trivalent europium complex Eu(TTA){sub 3}phen (TTA=thenoyltrifluoroacetone and phen=1,10-phenanthroline) by designing the device structure with stepwise energy levels. The widely used bipolar material 2,6-bis(3-(9H-carbazol-9-yl)phenyl)pyridine (26DCzPPy) was chosen as host material, while the doping concentration of Eu(TTA){sub 3}phen was optimized to be 4%. To facilitate the injection and transport of holes, MoO{sub 3} anode modification layer and 4,4′,4′′-Tris(carbazole-9-yl)triphenylamine (TcTa) hole transport layer were inserted in sequence. Efficient pure red emission with suppressed efficiency roll-off was obtained attributed to the reduction of accumulation holes, the broadening of recombination zone, and the improved balance of holes and electrons on Eu(TTA){sub 3}phen molecules. Finally, the device with 3 nm MoO{sub 3} and 5 nm TcTa obtained the highest brightness of 3278 cd/m{sup 2}, current efficiency of 12.45 cd/A, power efficiency of 11.50 lm/W, and external quantum efficiency of 6.60%. Such a device design strategy helps to improve the EL performances of emitters with low-lying energy levels and provides a chance to simplify device fabrication processes. - Highlights: • Electroluminescent performances of europium complex were further improved. • Device structure with stepwise energy levels was designed. • Better carriers' balance was realized by improving the injection and transport of holes. • The selection of bipolar host caused the broadening of recombination zone.

  9. A lanthanide complex with dual biosensing properties: CEST (chemical exchange saturation transfer) and BIRDS (biosensor imaging of redundant deviation in shifts) with europium DOTA-tetraglycinate.

    Science.gov (United States)

    Coman, Daniel; Kiefer, Garry E; Rothman, Douglas L; Sherry, A Dean; Hyder, Fahmeed

    2011-12-01

    Responsive contrast agents (RCAs) composed of lanthanide(III) ion (Ln3R) complexes with a variety of1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (DOTA4S) derivatives have shown great potential as molecular imaging agents for MR. A variety of LnDOTA–tetraamide complexes have been demonstrated as RCAs for molecular imaging using chemical exchange saturation transfer (CEST). The CEST method detects proton exchange between bulk water and any exchangeable sites on the ligand itself or an inner sphere of bound water that is shifted by a paramagnetic Ln3R ion bound in the core of the macrocycle. It has also been shown that molecular imaging is possible when the RCA itself is observed (i.e. not its effect on bulk water) using a method called biosensor imaging of redundant deviation in shifts (BIRDS). The BIRDS method utilizes redundant information stored in the nonexchangeable proton resonances emanating from the paramagnetic RCA for ambient factors such as temperature and/or pH.Thus, CEST and BIRDS rely on exchangeable and nonexchangeable protons, respectively, for biosensing. We posited that it would be feasible to combine these two biosensing features into the same RCA (i.e. dual CEST and BIRDS properties). A complex between europium(III) ion (Eu3R) and DOTA–tetraglycinate [DOTA–(gly)S4] was used to demonstrate that its CEST characteristics are preserved, while its BIRDS properties are also detectable. The in vitro temperature sensitivity of EuDOTA–(gly)S4 was used to show that qualitative MR contrast with CEST can be calibrated using quantitative MR mapping with BIRDS, thereby enabling quantitative molecular imaging at high spatial resolution.

  10. 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)

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

    International Nuclear Information System (INIS)

    Kautenburger, R.; Nowotka, K.; Beck, H.P.

    2005-01-01

    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 3+ ) and gadolinium (Gd 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 μl 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 153 Eu and 125 ppt for 158 Gd. With this optimized CE-ICP-MS coupling

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

    International Nuclear Information System (INIS)

    Zamani, Hassan Ali; Kamjoo, Rahman; Mohammadhosseini, Majid; Zaferoni, Mojdeh; Rafati, Zynab; Ganjali, Mohammad Reza; Faridbod, Farnoush; Meghdadi, Soraia

    2012-01-01

    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 × 10 −2 and 1.0 × 10 −6 mol L −1 , Nernstian slope of 19.8 ± 0.3 mV per decade and a detection limit of 6.4 × 10 −7 mol L −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 3+ ions with EDTA and for determination of Eu 3+ ion concentration in mixtures of two and three different ions. - Highlights: ► A new ion carrier is introduced to preparation of a selective sensor for Eu 3+ ions. ► This technique is very simple and it's not necessary to use sophisticated equipment. ► The novelty of this work is the high affinity of the ionophore toward the Eu 3+ ions. ► The sensor is superior to the formerly reported Eu 3+ sensors in terms of selectivity.

  13. 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.

  14. Spectroscopic studies of europium-tetracyclines complexes and their applications in detection of hydrogen peroxide and urea peroxide; Estudos espectroscopicos dos complexos europio-tetraciclinas e suas aplicacoes na detecao de peroxido de hidrogenio e peroxido de ureia

    Energy Technology Data Exchange (ETDEWEB)

    Grasso, Andrea Nastri

    2010-07-01

    In this work were studied the spectroscopic properties of trivalent europium ion complexed with components of tetracycline family, chlorotetracycline, oxytetracycline and metacycline, in the presence of hydrogen peroxide and urea peroxide. Optical parameters were obtained such as absorption, emission, lifetime and calibration curves were constructed for luminescence spectra. Experiments were carried out with both inorganic compounds and europium-tetracyclines complexes in order to verify possible interferences. Studies for glucose determination were also described using europium-tetracyclines complexes as biosensors. Results show that europium tetracyclines complexes emit a narrow band in the visible region and, in the presence of hydrogen peroxide or urea peroxide there is a greater enhancement in their luminescence and lifetime. Thus, europium-tetracyclines complexes studied can be used as biosensors for hydrogen and urea peroxides determination as a low cost and room temperature method. An indirect method for glucose determination was studied by adding glucose oxidase enzyme in europium-tetracyclines complex in the presence of glucose promoting as product hydrogen peroxide. (author)

  15. Fluorimetric study of the interaction between nicotinamide adenine dinucleotide phosphate and tetracycline-europium complex and its application

    International Nuclear Information System (INIS)

    Peng Qian; Hou Faju; Ge Xiaoxia; Jiang Chongqiu; Gong Shubo

    2005-01-01

    A new spectrofluorimetric method was developed for the determination of trace amount of nicotinamide adenine dinucleotide phosphate (NADP). Using europium (Eu 3+ )-tetracycline (TC) complex as a fluorescent probe, in the buffer solution of pH 7.60. NADP can remarkably enhance the fluorescence intensity of the Eu 3+ -TC complex at λ = 612 nm and the enhanced fluorescence intensity of Eu 3+ ion is in proportion to the concentration of NADP. Optimum conditions for the determination of NADP were also investigated. The dynamic range for the determination of NADP is 4.4 x 10 -7 to 2.2 x 10 -6 mol l -1 with detection limit of 6.9 x 10 -8 mol l -1 . This method is simple, practical and relatively free interference from coexisting substances and can be successfully applied to determination of NADP in synthetic water samples and in serum samples. Moreover, the enhancement mechanisms of the fluorescence intensity in the Eu 3+ -TC system and the Eu 3+ -TC-NADP system have been also discussed

  16. 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 (λ irr = 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.

  17. Genetics Home Reference: mitochondrial complex III deficiency

    Science.gov (United States)

    ... the energy from food into a form that cells can use. Complex III is one of several complexes that ... in mtDNA. Because egg cells, but not sperm cells, contribute mitochondria to the ... from their mother. These disorders can appear in every generation of ...

  18. Complexes between lanthanide (III) and yttrium (III) picrates and tetra methylene sulfoxide as ligand

    International Nuclear Information System (INIS)

    Silva, M.A.A. da.

    1991-01-01

    The preparation and characterization of addition compounds between lanthanide (III) and yttrium (III) picrates and tetra methylene sulfoxide as ligand were described. The adducts were prepared in the molar relation 1 (salt): 3(ligand) in ethanol. They are microcrystalline with more intense color than those of their respective hydrated salts. At room temperature conditions they are non hygroscopic and do not present perceptible alterations. They became slightly opalescent, when heated between 363 and 423 K. At higher temperatures under several heating ratios, the behavior shown is the same: melting between 439 and 472 K. The characterization of the compounds was made by elemental analysis, electrolytic conductance measurements, X-ray powder patterns, infrared spectroscopy, visible electronic absorption and emission spectra of the neodymium (III) and europium (III), respectively. (author). 116 refs., 17 tabs., 11 figs

  19. Raman, photoluminescence and EPR spectroscopic characterization of europium(III) oxide–lead dioxide–tellurite glassy network

    Energy Technology Data Exchange (ETDEWEB)

    Dehelean, A. [National Research and Development Institute for Isotopic and Molecular Technologies, Cluj-Napoca (Romania); Rada, S. [Technical University of Cluj-Napoca (Romania); Popa, A.; Suciu, R.C. [National Research and Development Institute for Isotopic and Molecular Technologies, Cluj-Napoca (Romania); Culea, E., E-mail: eugen.culea@phys.utcluj.ro [Technical University of Cluj-Napoca (Romania)

    2016-09-15

    Raman, photoluminescence and EPR spectroscopies were used to characterize some xEu{sub 2}O{sub 3}·(100−x)[4TeO{sub 2}·PbO{sub 2}] glasses with x=0–50 mol% obtained by melt quenching technique. Raman spectra of these glasses were interpreted in terms of vibration modes of deformed Te–O–Te linkages due to the intercalation of [PbO{sub n}] and [EuO{sub n}] entities produced by addition of Eu{sub 2}O{sub 3} to the host lead–tellurite glass. Photoluminescence spectra of xEu{sub 2}O{sub 3}·(100−x)[4TeO{sub 2}·PbO{sub 2}] glasses reveal the presence of Pb{sup 2+}, Eu{sup 2+} and Eu{sup 3+} ions. EPR data confirm the presence of Eu{sup 2+} ions in the europium–lead–tellurite glassy network and offer information about the compositional evolution of the Eu{sup 2+} ions local environment and Eu{sup 3+}↔Eu{sup 2+} redox process. PL and EPR data show that the decrease of the Eu{sup 2+} ions luminescence intensity for the x≥40 mol% Eu{sub 2}O{sub 3} region is not due to the clusterization of europium ions but is due the decrease of the amount of Eu{sup 2+} ions as result of changes in the Eu{sup 3+}→Eu{sup 2+} redox equilibrium.

  20. Hydrothermal synthesis and crystal structure of a europium(III) coordination polymer with 5-sulfoisophthalate trivalent anions and free 4, 4'-bipyridine molecules

    International Nuclear Information System (INIS)

    Lin Humao; Qing Caixiao; Qian Miao; Ping Xiaohong

    2005-01-01

    A novel europium(III) coordination polymer [Eu(Sip)(H 2 O) 5 ] n · nH 2 O · 1.5 n(Bipy) (I) (Sip is 5-sulfoisophthalate trivalent anion and Bipy is 4,4'-bipyridine) is hydrothermally synthesized and determined by the single crystal X-ray diffraction method. Polymer I crystallizes in the monoclinic system, space group C2/c with a = 30.7515(6), b = 10.9577(2), c = 17.5545(4) A, β = 112.040(1) deg, Z = 4. In I, each Eu 3+ ion is coordinated by four oxygen atoms from two carboxylate groups of two different Sip anions and five oxygen atoms from five coordinated water molecules to complete a deformed mono-cap square antiprism. Moreover, each Sip anion acts as a tetradentate ligand to connect two adjacent Eu 3+ ions through its two chelating carboxylate groups, resulting in one-dimensional linear chains. In addition, fifteen different kinds of hydrogen-bonding interactions link the chains, lattice water molecules, and free Bipy molecules to engender a complicated hydrogen-bonding network [ru

  1. Novel luminescent Langmuir-Blodgett films of europium complex embedded in titania matrix

    International Nuclear Information System (INIS)

    Zhang Li; Liu, H.-G.; Kang, S.-Z.; Mu, Y.-D.; Qian, D.-J.; Lee, Yong-Ill; Feng Xusheng

    2005-01-01

    A stable Eu(DBM) 3 (DB-bpy)/AA/TiO 2 monolayer was formed on the surface of a composite subphase by spreading an Eu(DBM) 3 (DB-bpy)/AA/TBT chloroform solution. DBM, DB-bpy, AA and TBT refer to dibenzoylmethanate, 4,4'-Di-tert-butyl-2,2'-bipyridine, arachidic acid and tetrabutyloxyltitanium, respectively. Eu(DBM) 3 (DB-bpy)/AA/TiO 2 Langmuir-Blodgett films were deposited on solid substrates and were characterized by low-angle X-ray diffractometry, UV-visible (UV refers to ultra-violet) spectroscopy, photoluminescent spectroscopy and electron probe microanalysis. The results show that a luminescent composite film with layered structure was fabricated, which shows characteristic emission of Eu(III)

  2. Complexes of 4-chlorophenoxyacetates of Nd(III), Gd(III) and Ho(III)

    International Nuclear Information System (INIS)

    Ferenc, W.; Bernat, M; Gluchowska, H.W.; Sarzynski, J.

    2010-01-01

    The complexes of 4-chlorophenoxyacetates of Nd(III), Gd(III) and Ho(III) have been synthesized as polycrystalline hydrated solids, and characterized by elemental analysis, spectroscopy, magnetic studies and also by X-ray diffraction and thermogravimetric measurements. The analysed complexes have the following colours: violet for Nd(III), white for Gd(III) and cream for Ho(III) compounds. The carboxylate groups bind as bidentate chelating (Ho) or bridging ligands (Nd, Gd). On heating to 1173K in air the complexes decompose in several steps. At first, they dehydrate in one step to form anhydrous salts, that next decompose to the oxides of respective metals. The gaseous products of their thermal decomposition in nitrogen were also determined and the magnetic susceptibilities were measured over the temperature range of 76-303K and the magnetic moments were calculated. The results show that 4-chlorophenoxyacetates of Nd(III), Gd(III) and Ho(III) are high-spin complexes with weak ligand fields. The solubility value in water at 293K for analysed 4-chlorophenoxyacetates is in the order of 10 -4 mol/dm 3 . (author)

  3. Fe (III) complex of mefloquine hydrochloride: Synthesis ...

    African Journals Online (AJOL)

    As part of the ongoing research for more effective antimalarial drug, Fe (III) complex of mefloquine hydrochloride (antimalarial drug) was synthesized using template method. Mefloquine was tentatively found to have coordinated through the hydroxyl and the two nitrogen atoms in the quinoline and piperidine in the structure, ...

  4. Spectrophotometric investigation of addition compounds between neodymium (III) and europium (III) perchorates and hexafluorophosphate and cyclic ligants with two oxygen in opposite position

    International Nuclear Information System (INIS)

    Oliveira, M.A.S.

    1986-01-01

    Addition compounds between Nd 3+ and Eu 3+ perchlorates and hexafluorophosphates with trans-1,4-dithino-1,4-dioxide (TDTD), pyrazine-1,4-dioxide (pyzDO), 2,5 - piperazinedione (pdo) and 1-4-diazabicyclo /2,2,2/-octane-1,4-dioxide or triethylenediamine dioxide (TEDADO) were prepared. The lanthanide content was determined by complexometric titration with EDTA. Carbon, hydrogen and nitrogen were determined by microanalytical procedures and water by the Karl Fischer method. The following stoichiometries were determined: Nd(ClO 4 ) 3 .6TDTD.8H 2 O; Eu(ClO 4 ) 3 .6TDTD.4H 2 O; Ln(PF 6 ) 3 .4TDTD.4H 2 O; Ln(ClO 4 ) 3 .4pyzDO; Ln(ClO 4 ) 3 .4pdo; Ln(ClO 4 ) 3 .3TEDADO.3H 2 O; Ln(PF 6 ) 3 .3TEDADO.3H 2 O (Ln = Nd 3+ and Eu 3+ ). X-ray powder patterns of the perchlorates show that the compounds of neodymium and europium with the respective ligands are isomorphous. The samme occurs in relation to Nd 3+ and Eu 3+ hexafluorophosphates. The results of the infared spectra, Raman spectra, absorption electronic spectra and fluorescence electronic spectra are also presented. (author) [pt

  5. Europium-151 Moessbauer spectroscopic and XANES investigation of europium-exchanged Y-zeolite

    International Nuclear Information System (INIS)

    Berry, F.J.; Marco, J.F.; Steel, A.T.

    1994-01-01

    Eu 3+ in ca. 10 wt% europium-exchanged Y-zeolite is partially reduced by treatment in hydrogen at 600 C to Eu 2+ . The reduction of Eu 3+ is more readily achieved in Y-zeolite than in europium(III) oxide. The discrepancy in the extent of reduction as revealed by 151 Eu Moessbauer spectroscopy and near edge X-ray absorption fine structure (XANES) is associated with any difference in the recoil free fractions of Eu 2+ and Eu 3+ which may exist at 298 K and the enhanced sensitivity of the XANES to changes in the europium oxidation state. (orig.)

  6. Hot electron-induced time-resolved electrogenerated chemiluminescence of a europium(III) label in fully aqueous solutions

    International Nuclear Information System (INIS)

    Jiang, Q.; Hakansson, M.; Spehar, A.-M.; Ahonen, J.; Ala-Kleme, T.; Kulmala, S.

    2006-01-01

    Time-resolved electrogenerated chemiluminescence of multidentate phenolic Eu(III) chelates were studied in aqueous solution. 2,6-bis[N,N-bis(carboxymethyl)-aminomethyl]-4-benzoylphenol forms a photoluminescent and electrochemiluminescent Eu(III) chelate, whereas 2,6-bis[N,N-bis(carboxymethyl)-aminomethyl]-4-methyl phenol-chelated Eu(III) turned out to be not luminescent at all. The importance of the redox properties of both the ground and the excited states of the ligands and the central ion is shown. The former chelate shows relatively weak ECL at an oxide-covered aluminum electrode but the ECL intensity can be strongly enhanced by the addition of peroxodisulfate ions. In the presence of 1 mM peroxodisulfate ions the ECL lifetime of this chelate is 0.94 ms, thus easily allowing time-resolved detection of the chelate. This chelate can be conjugated to antibodies by thioureido linkage and used as an electrochemiluminescent label in immunoassays as a marker which displays long-lived luminescence in the red end of the optical spectrum. The present ECL is mainly based on the ligand sensitized redox excitation of the chelate by analogous pathways to those known from the studies of aromatic Tb(III) chelates but the energy transfer from the emission centers of the aluminum oxide film can also have minor contribution to the excitation of the label

  7. Sensing of phosphates by using luminescent Eu(III) and Tb(III) complexes: application to the microalgal cell Chlorella vulgaris.

    Science.gov (United States)

    Nadella, Sandeep; Sahoo, Jashobanta; Subramanian, Palani S; Sahu, Abhishek; Mishra, Sandhya; Albrecht, Markus

    2014-05-12

    Phenanthroline-based chiral ligands L(1) and L(2) as well as the corresponding Eu(III) and Tb(III) complexes were synthesized and characterized. The coordination compounds show red and green emission, which was explored for the sensing of a series of anions such as F(-), Cl(-), Br(-), I(-), NO3(-), NO2(-), HPO4(2-), HSO4(-), CH3COO(-), and HCO3(-). Among the anions, HPO4(2-) exhibited a strong response in the emission property of both europium(III) and terbium(III) complexes. The complexes showed interactions with the nucleoside phosphates adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP). Owing to this recognition, these complexes have been applied as staining agents in the microalgal cell Chlorella vulgaris. The stained microalgal cells were monitored through fluorescence microscopy and scanning electron microscopy. Initially, the complexes bind to the outer cell wall and then enter the cell wall through holes in which they probably bind to phospholipids. This leads to a quenching of the luminescence properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Silica- and silylated europium-based luminescent hybrids: new analysis tools for biological environments

    International Nuclear Information System (INIS)

    Pereira Duarte, Adriana

    2012-01-01

    The association of the very interesting luminescence properties of the lanthanide chelates with the physicochemical properties of inorganic matrix such as silica is a promising way to obtain new probes or luminescent markers for biology analyses. In this idea, this work focuses on the preparation of new hybrid materials based on the grafting of new europium(III) complexes on silica nanoparticles. These europium complexes were developed in our group using bifunctional ligands containing both complexing and grafting sites. Intrinsic characteristic of the ligands gives us the ability to make a covalent bond between the material surface and the complex. Two different methodologies were used; the first one is the direct grafting reaction involving the complex and silica nanoparticles (i.e. dense or meso-porous particles). The second one is the Stoeber reaction, where the SiO 2 nanoparticles were prepared in presence of the europium complex. The last methodology has an additional difficult, because of the presence of silylated europium complex, it needs a closer control of the physicochemical conditions. The new organic-inorganic hybrid materials, obtained in this work, present an interesting luminescence behavior and this one is depending on the localization of the europium complex, i.e. on the surface or within the nanoparticles. In addition, the obtained hybrids present the nano-metric dimension and the complex is not leachable. Analyses were realized to describe the luminescence properties, beyond surface and structural characteristics. Initial results show that the new hybrids are promising candidates for luminescent bio-markers, particularly for the time-resolved analysis. (author) [fr

  9. Bright electroluminescence from a chelate phosphine oxide Eu{sup III} complex with high thermal performance

    Energy Technology Data Exchange (ETDEWEB)

    Xu Hui [School of Chemistry and Materials, Heilongjiang University, 74 Xuefu Road, Nangang District, Harbin 150080, Heilongjiang Province (China); Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, 66 Xinmofan Road, Nanjing 21003, Jiangsu Province (China); Yin Kun; Wang Lianhui [Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, 66 Xinmofan Road, Nanjing 21003, Jiangsu Province (China); Huang Wei [Institute of Advanced Materials (IAM), Fudan University, 220 Handan Road, Shanghai 200433 (China)], E-mail: wei-huang@njupt.edu.cn

    2008-10-01

    The chelate phosphine oxide ligand 1,8-bis(diphenylphosphino)naphthalene oxide (NaPO) was used to prepare complex 1 tris(2-thenoyltrifluoroacetonate)(1,8-bis(diphenylphosphino)naphthalene oxide)europium(III). The rigid structure of NaPO makes 1 have more compact structure resulting in a temperature of glass transition as high as 147 deg. C, which is the highest in luminescent Eu{sup III} complexes, and a higher decomposition temperature of 349 deg. C. The improvement of carrier transfer ability of NaPO was proved by Gaussian simulation. The multi-layered electroluminescent device based on 1 had a low turn-on voltage of 6.0 V, the maximum brightness of 601 cd m{sup -2} at 21.5 V and 481.4 mA cm{sup -2}, and the excellent voltage-independent spectral stability. These properties demonstrated NaPO cannot only be favorable to form the rigid and compact complex structure, and increase the thermal and morphological stability of the complex, but also reduce the formation of the exciplex.

  10. Synthesis, spectroscopic characterization, solid state d.c. electrical conductivity and biological studies of some lanthanide(III chloride complexes with a heterocyclic Schiff base ligand

    Directory of Open Access Journals (Sweden)

    K. Mohanan

    2016-07-01

    Full Text Available Condensation of 2-hydroxy-1-naphthaldehyde with 2-amino-3-carboxyethyl-4,5-dimethylthiophene in 1:1 molar ratio, yielded a potentially tridentate Schiff base viz. 2-[N-(2′-hydroxy-1-naphthylideneamino]-3-carboxyethyl-4,5-dimethylthiophene (HNAT. This ligand formed complexes with lanthanum(III, cerium(III, praseodymium(III, neodymium(III, samarium(III, europium(III and gadolinium(III chloride under well defined conditions. These complexes were characterized through elemental analysis, molar conductance, magnetic moment measurements, IR, UV–Vis, FAB mass and 1H NMR spectral studies. Analytical data showed that all the metal complexes exhibited 1:1 metal–ligand ratio. Molar conductance values adequately confirmed the non-electrolytic nature of the metal complexes. The proton NMR spectral observations supplement the IR spectral assignments. The spectral data revealed that the ligand acted as neutral tridentate, coordinating to the metal ion through azomethine nitrogen, ester carbonyl and naphtholate oxygen without deprotonation. The ligand and its lanthanum(III chloride complex were subjected to XRD studies. The lanthanum(III chloride complex has undergone a facile transesterification reaction. The solid state d.c. electrical conductivity of some selected complexes were measured as a function of temperature, indicating the semiconducting nature of the metal complexes. The antimicrobial activities were examined by disk diffusion method against some pathogenic bacterial and fungal species.

  11. 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)

  12. Sol-gel approach to the novel organic-inorganic hybrid composite films with ternary europium complex covalently bonded with silica matrix

    International Nuclear Information System (INIS)

    Dong Dewen; Yang Yongsheng; Jiang Bingzheng

    2006-01-01

    Novel organic-inorganic hybrid composite films with ternary lanthanide complex covalently bonded with silica matrix were prepared in situ via co-ordination of N-(3-propyltriethoxysilane)-4-carboxyphthalimide (TAT) and 1,10-phenanthroline (Phen) with europium ion (Eu 3+ ) during a sol-gel approach and characterized by the means of spectrofluorimeter, phosphorimeter and infrared spectrophotometer (FTIR). The resulting transparent films showed improved photophysical properties, i.e. increased luminescence intensity and longer luminescence lifetime, compared with the corresponding binary composite films without Phen. All the results revealed that the intense luminescence of the composite film was attributed to the efficient energy transfer from ligands, especially Phen, to chelated Eu 3+ and the reduced non-radiation through the rigid silica matrix and 'site isolation'

  13. Complexes of lanthanum(III), cerium(III), samarium(III) and dysprosium(III) with substituted piperidines

    Energy Technology Data Exchange (ETDEWEB)

    Manhas, B S; Trikha, A K; Singh, H; Chander, M

    1983-11-01

    Complexes of the general formulae M/sub 2/Cl/sub 6/(L)/sub 3/.C/sub 2/H/sub 5/OH and M/sub 2/(NO/sub 3/)/sub 6/(L)/sub 2/.CH/sub 3/OH have been synthesised by the reactions of chlorides and nitrates of La(III), Ce(III), Sm(III) and Dy(III) with 2-methylpiperidine, 3-methylpiperidine and 4-methylpiperidine. These complexes have been characterised on the basis of their elemental analysis, and IR and electronic reflectance spectra. IR spectral data indicate the presence of coordinated ethanol and methanol molecules and bidentate nitrate groups. Coordination numbers of the metal ions vary from 5 to 8. 19 refs.

  14. Infinite Particle Systems: Complex Systems III

    Directory of Open Access Journals (Sweden)

    Editorial Board

    2008-06-01

    Full Text Available In the years 2002-2005, a group of German and Polish mathematicians worked under a DFG research project No 436 POL 113/98/0-1 entitled "Methods of stochastic analysis in the theory of collective phenomena: Gibbs states and statistical hydrodynamics". The results of their study were summarized at the German-Polish conference, which took place in Poland in October 2005. The venue of the conference was Kazimierz Dolny upon Vistula - a lovely town and a popular place for various cultural, scientific, and even political events of an international significance. The conference was also attended by scientists from France, Italy, Portugal, UK, Ukraine, and USA, which predetermined its international character. Since that time, the conference, entitled "Infinite Particle Systems: Complex Systems" has become an annual international event, attended by leading scientists from Germany, Poland and many other countries. The present volume of the "Condensed Matter Physics" contains proceedings of the conference "Infinite Particle Systems: Complex Systems III", which took place in June 2007.

  15. 3,4,3-LI(1,2-HOPO): In Vitro Formation of Highly Stable Lanthanide Complexes Translates into Efficacious In Vivo Europium Decorporation

    Energy Technology Data Exchange (ETDEWEB)

    Sturzbecher-Hoehne, Manuel; Ng Pak Leung, Clara; Daleo, Anthony; Kullgren, Birgitta; Prigent, Anne-Laure; Shuh, David K.; Raymond, Kenneth N.; Abergel, Rebecca J.

    2011-07-13

    The spermine-based hydroxypyridonate octadentate chelator 3,4,3-LI(1,2-HOPO) was investigated for its ability to act as an antennae that sensitizes the emission of Sm{sup III}, Eu{sup III}, and Tb{sup III} in the Visible range (Φ{sub tot} = 0.2 - 7%) and the emission of Pr{sup III}, Nd{sup III}, Sm{sup III}, and Yb{sup III} in the Near Infra-Red range, with decay times varying from 1.78 μs to 805 μs at room temperature. The particular luminescence spectroscopic properties of these lanthanide complexes formed with 3,4,3-LI(1,2-HOPO) were used to characterize their respective solution thermodynamic stabilities as well as those of the corresponding La{sup III}, Gd{sup III}, Dy{sup III}, Ho{sup III}, Er{sup III}, Tm{sup III}, and Lu{sup III} complexes. The remarkably high affinity of 3,4,3-LI(1,2-HOPO) for lanthanide metal ions and the resulting high complex stabilities (pM values ranging from 17.2 for La{sup III} to 23.1 for Yb{sup III}) constitute a necessary but not sufficient criteria to consider this octadentate ligand an optimal candidate for in vivo metal decorporation. The in vivo lanthanide complex stability and decorporation capacity of the ligand were assessed, using the radioactive isotope {sup 152}Eu as a tracer in a rodent model, which provided a direct comparison with the in vitro thermodynamic results and demonstrated the great potential of 3,4,3-LI(1,2-HOPO) as a therapeutic metal chelating agent.

  16. Moessbauer study of Fe(III)-reducing sugar complexes

    International Nuclear Information System (INIS)

    Wolowiec, S.; Drabent, K.

    1985-01-01

    Iron(III) complexes with glucose, galactose, mannose and lactose were prepared. The Moessbauer and magnetic susceptibility data demonstrate the polymeric structure of the complexes. The thermal behaviour of the Fe(III)-glucose complex was monitored by Moessbauer spectroscopy. (author)

  17. Synthesis of hydrosoluble cryptophanes, designed to encapsulate xenon, and of hemi-cryptophanes functionalized to complex lanthanide (III) ions, with the intention to apply them in medical imaging

    International Nuclear Information System (INIS)

    Godart, Estelle

    2017-01-01

    This book details all the research work that has been done during three years of Ph-D. After a chapter dedicated to the general principles of supramolecular chemistry, and some of its applications, we focalize on the use of cage-shapes molecules (cryptophanes and hemi-cryptophanes) in order to build probes for biological imaging. We successively mention the way toward the synthesis of a hemi-cryptophane able to complex Gadolinium(III), to use it it as a proton-MRI contrast agent, then toward the elaboration of hydrosoluble cryptophanes adapted to 129 Xe NMR and MRI. This PhD manuscript ends with the synthesis of a new hemi-cryptophane functionalized to form complexes with Terbium(III) and Europium(III), whose fluorescence properties are promising. (author)

  18. Characterisation of kaolinite and adsorption of europium on kaolinite

    International Nuclear Information System (INIS)

    Olin, M.; Puhakka, E.; Lehikoinen, J.; Puukko, E.; Hakanen, M.; Lindberg, A.

    2007-10-01

    Kaolinite is a common fracture mineral in many crystalline rocks and, thus, a potential sorbent for groundwater solutes. The low cation-exchange capacity makes kaolinite a good mineral to study sorption by inner-sphere complexation of multivalent ions, such as trivalent actinides or their analogues, the trivalent lanthanides. The sorption of europium and americium on kaolinite has been studied previously by Puukko and Hakanen using a natural kaolinite, KGa-1b (from the Clay Minerals Society, USA). This work describes the determination of surface-charging mechanism and surface acidity constants for KGa-1b kaolinite, and adsorption of Eu(III) on both the natural (KGa-1b) and its acid-conditioned form (HKGa). The ionic strength of the background NaNO 3 electrolyte used in these titrations was 0.05 M, 0.1 M and 0.5 M. The surface acidity of kaolinite was explained using the FITEQL software by applying the 1-pK model. The optimized concentration of surface sites was close to a value previously reported for KGa-1b kaolinite. The adsorption modelling of europium was carried out by adopting one surfacecomplexation and one cation-exchange reaction. In the acidic pH range, sorption of europium decreased with increasing ionic strength of the NaNO 3 solution, which is an indication of the dominance of cation exchange or outer-sphere complexation. At the lowest ionic strength, the sorption was reversible. In the 0.1 M and 0.5 M NaNO 3 solutions, the sorption of europium in the basic pH range was only partly reversible, or desorption kinetically slow. The degree of irreversibility increased with increasing pH and ionic strength. A diffuse-layer model was readily fitted on the per-cents sorbed scale (default in FITEQL), but the results were not as good on a Kd scale, especially at circumneutral pH values. In the water analysis of the batch titration of KGa-1b kaolinite, the main observed elements were aluminium and zinc. The concentrations of Al and Zn decreased with p

  19. Studies on the rare earth complexes with pyridine derivatives and their N-oxide(II) - Synthesis and properties of fluorescent solid complexes of samarium, europium, gadolium and terbium chlorides with 2,2'-bipyridine-N,N'-dioxide

    International Nuclear Information System (INIS)

    Minyu, T.; Ning, T.; Yingli, Z.; Jiyuan, B.

    1985-01-01

    The solid complexes of rare earth nitrates perchlorates and thiocyanates with 2,2'-bipyridine-N,N'-dioxide (bipyO/sub 2/) have been reported. However, the corresponding complexes of other rear earth chlorides have not been investigated except lanthanum, cerium and yttrium. As an extension of our previous work on the synthesis of complexes of praseodymium and neodymium chlorides wiht bipoyO/sub 2/, the authors have now prepared fluorescent solid complexes of samarium, europium, gadolium and terbium chlorides with biphyO/sub 2/, using methanol as a reaction medium. The new synthesized compounds have been identified by means of elemental analysis, infrared spectrometry, conductometry, differential thermal analysis (DTA), thermogravimetry (TG) and X-ray powder diffraction

  20. Synthesis of samarium, europium and ytterbium acetylenides

    International Nuclear Information System (INIS)

    Bochkarev, M.N.; Fedorova, E.A.; Glushkova, N.V.; Protchenko, A.V.; Druzhkov , O.N.; Khorshev, S.Ya.

    1995-01-01

    Ethynyl complexes of samarium, europium and ytterbium were prepared by interaction of naphthalinides of metals with acetylene in tetrahydrofuran. The compounds are isolated in the form of dark-coloured pyrophore powders. Data of magnetic measurements suggest that in the course of the reaction Sm(2) is oxidized completely to Sm(3), Yb(2) transforms into Yb(3) partially, whereas europium preserves its initial bivalent state. Hydrolysis of the compounds prepared provides acetylene, ethylene, ethane and hydrogen which indicates the presence of acethylenide Ln 2 C 2 and hydride LnH groupings (Ln = Sm, Eu, Yb). 9 refs., 2 tabs

  1. Synthesis and infrared spectra of Vanadium (III) prussian blue complexes

    International Nuclear Information System (INIS)

    Toma, H.E.; Lellis, F.T.P.

    1987-01-01

    The synthesis and characterization of a series of polymeric pigments containing vanadium (III) and hexacryano or substituted pentacyanoferrate (II) complexes are studied. The role of the intervalence transfer interactions in the complexes is discussed. (M.J.C.) [pt

  2. 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)

  3. Spectrophotometric and pH-Metric Studies of Ce(III, Dy(III, Gd(III,Yb(III and Pr(III Metal Complexes with Rifampicin

    Directory of Open Access Journals (Sweden)

    A. N. Sonar

    2011-01-01

    Full Text Available The metal-ligand and proton-ligand stability constant of Ce(III, Dy(III, Gd(III,Yb(III and Pr(III metals with substituted heterocyclic drug (Rifampicin were determined at various ionic strength by pH metric titration. NaClO4 was used to maintain ionic strength of solution. The results obtained were extrapolated to the zero ionic strength using an equation with one individual parameter. The thermodynamic stability constant of the complexes were also calculated. The formation of complexes has been studied by Job’s method. The results obtained were of stability constants by pH metric method is confirmed by Job’s method.

  4. Study of the luminescence of tris(2-thenoyltrifluoroacetonato)lanthanide(III) complexes covalently linked to 1,10-phenanthroline-functionalized hybrid sol-gel glasses

    International Nuclear Information System (INIS)

    Lenaerts, Philip; Ryckebosch, Eline; Driesen, Kris; Deun, Rik van; Nockemann, Peter; Goerller-Walrand, Christiane; Binnemans, Koen

    2005-01-01

    The solubility and uniform distribution of lanthanide complexes in sol-gel glasses can be improved by covalently linking the complexes to the sol-gel matrix. In this study, several lanthanide β-diketonate complexes (Ln=Nd, Sm, Eu, Tb, Er, Yb) were immobilized on a 1,10-phenanthroline functionalized sol-gel glass. For the europium(III) complex, a sol-gel material of diethoxydimethylsilane (DEDMS) with polymer-like properties was derived. For the other lanthanide complexes, the sol-gel glass was prepared by using a matrix of tetramethoxysilane (TMOS) and DEDMS. Both systems were prepared under neutral reaction conditions. High-resolution emission and excitation spectra were recorded. The luminescence lifetimes were measured

  5. Complexes of (III) lanthanides isothiocyanate and (III) yttrium with 2,6-lutidine-n-oxide (2,6-LNO)

    International Nuclear Information System (INIS)

    Arico, E.M.

    1990-01-01

    The preparation and characterization of the complexes of yttrium and some lanthanides isothiocyanate with 2,6-lutidine-N-oxide (2,6-LNO) are described. The ligand employed in the synthesis of the compounds were prepared by the reaction of 2,6-lutidine with hydrogen peroxide in glacial acetic acid. The complexes were prepared using the relation 1:3 salt-ligand. Their characterization was made by elemental analysis, electrolytic conductance measurements, X-ray powder patterns, infrared spectra, electronic absorption spectra of the neodymium and fluorescence spectra of the europium compounds. (author)

  6. NMR and TRLFS studies of Ln(iii) and An(iii) C5-BPP complexes.

    Science.gov (United States)

    Adam, Christian; Beele, Björn B; Geist, Andreas; Müllich, Udo; Kaden, Peter; Panak, Petra J

    2015-02-01

    C5-BPP is a highly efficient N-donor ligand for the separation of trivalent actinides, An(iii), from trivalent lanthanides, Ln(iii). The molecular origin of the selectivity of C5-BPP and many other N-donor ligands of the BTP-type is still not entirely understood. We present here the first NMR studies on C5-BPP Ln(iii) and An(iii) complexes. C5-BPP is synthesized with 10% 15 N labeling and characterized by NMR and LIFDI-MS methods. 15 N NMR spectroscopy gives a detailed insight into the bonding of C5-BPP with lanthanides and Am(iii) as a representative for trivalent actinide cations, revealing significant differences in 15 N chemical shift for coordinating nitrogen atoms compared to Ln(iii) complexes. The temperature dependence of NMR chemical shifts observed for the Am(iii) complex indicates a weak paramagnetism. This as well as the observed large chemical shift for coordinating nitrogen atoms show that metal-ligand bonding in Am(C5-BPP) 3 has a larger share of covalence than in lanthanide complexes, confirming earlier studies. The Am(C5-BPP) 3 NMR sample is furthermore spiked with Cm(iii) and characterized by time-resolved laser fluorescence spectroscopy (TRLFS), yielding important information on the speciation of trace amounts of minor complex species.

  7. Structural characterization of the Actinides (III) and (IV) - DOTA complexes

    International Nuclear Information System (INIS)

    Audras, Matthieu

    2014-01-01

    The polyamino-carboxylate anions have been identified as compounds of interest in the operations of actinide separation, in actinide migration in the environment and in human radio-toxicology. The structural characterization of complexes formed between actinides and polyamino-carboxylates ligands is essential for a better understanding of actinide-ligands interactions. Among the polyamino-carboxylate anions, the DOTA ligand (1,4,7,10-tetraaza-cyclododecane tetraacetic acid) is described as a very strong complexing agent of the lanthanides(III), but has been little studied with actinides. The objective of this thesis is to describe the complexes formed between the actinides (III) and (IV) and the DOTA ligand, and compare them with the lanthanide complexes. For this, an approach has been introduced to characterize the complexes by complementary analytical techniques (spectrophotometry, electro-spray ionization mass spectrometry, NMR, EXAFS, electrochemistry), but also by calculations of theoretical chemistry to help the interpretation of the experimental data. The formation of a 1:1 complex is observed with the actinides(III) (plutonium and americium) as for lanthanides(III): rapid formation of intermediate species which evolves slowly towards the formation of a limit complex. Within this complex, the cation is located inside the cavity formed by the ligand. Four nitrogen atoms and four oxygen atoms from the carboxylate functions are involved in the coordination sphere of the cation. However, differences were observed in the bond lengths formed between the cation and the nitrogen atoms (the bonds are somewhat shorter in the case of actinide complexes) as well as the complexation kinetics, which is slightly faster for the actinides(III) than for lanthanide(III) ions of equivalent radius. The same behavior was observed in solution upon complexation of actinides(IV) (uranium, plutonium and neptunium): slow formation of a 1:1 complex (actinide(IV):ligand) in wherein the

  8. Interaction mode between methylene blue-Sm(III) complex and ...

    African Journals Online (AJOL)

    Spectroscopic and viscosity methods were applied to investigate the interaction between methylene blue (MB)-Sm(III) complex and herring sperm DNA by using acridine orange as a spectral probe in Tris-HCl buffer (pH 7.40). By means of molar ratio method, the binding ratios between MB-Sm(III)and DNA were determined ...

  9. Synthesis and spectral properties of Chromium(III) complex of ...

    African Journals Online (AJOL)

    ISSCH) with chromium(III) chloride. The complex was characterized by molar conductance, magnetic moment, infrared, far-infrared and electronic spectra and elemental analysis. The ligand exists in keto tantomeric form and it coordinates through ...

  10. Enhancement of the fluorescence of the samarium (III) complex by gadolinium (III)

    International Nuclear Information System (INIS)

    Yun-Xiang, C.; Zhang-Hua, L.

    1988-01-01

    The increase in sensitivity and selectivity of reactions in which colored species are formed by the addition of different metal ions is an area of research that has recently been developed. This phenomenon, which is sometimes called cocolaration effect, has been explained by the formation of mixed metal complex. The authors found an analogous phenomenon of reactions forming fluorescent complexes. The complexes of Sm(III)-thenoyltrifluoroacetone (TTA)-phenanthroline (Phen)-Triton-X-100 (TX-100) and Gd(III) (or La(III), Lu(III) and Y(III))-TTA-Phen-TX-100 had practically no fluorescence separately. Instead, a fluorescence-enhancement phenomenon caused by adding Gd or La, Lu and Y ions to the system was observed for the first time. The intensity of the enhanced fluorescence of Sm(III) complex was increased in the following order: La< Y< Lu< Gd. By analogy with cocoloration effect, the authors call this new fluorescence-enhancement phenomenon the co-fluorescence effect. The object of this work was to study the enhancement effect of Gd(III) on the fluorescence of the Sm(III)-TTA-Phen-TX-100 system. The recommended fluorimetric method has been applied to the determination of trace amounts of samarium in ytterbium oxide with satisfactory results. A general reaction mechanism for the system studied was proposed

  11. Poly-β-hydroxybutyrate sensitizing effect on the photophysical properties of environment friendly fluorescent films containing europium complex

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chaolong, E-mail: yclzjun@163.com [School of Materials Science and Engineering, Chongqing University of Technology, Chongqing 400054 (China); Zhang, Pan; Zhou, Hualin [School of Materials Science and Engineering, Chongqing University of Technology, Chongqing 400054 (China); Xu, Jing [Department of Chemistry, Graduate School of Science, Tohoku University, Aramaki-Azaaoba 6-3, Aoba-ku, Sendai (Japan); Li, Youbing [School of Materials Science and Engineering, Chongqing University of Technology, Chongqing 400054 (China); Lu, Mangeng [Key Laboratory of Polymer Materials for Electronics, Guangzhou Institute of Chemistry, Chinese Academy of Sciences, Guangzhou 510650 (China); Lei, Lei; Zhang, Qiang; Zhang, Yi; Chen, Shaopeng [School of Materials Science and Engineering, Chongqing University of Technology, Chongqing 400054 (China)

    2016-10-15

    A series of environment friendly Eu/PHB fluorescent films through doped the Eu-complex precursor Eu(TTA){sub 2}(Tpy-OCH{sub 3})(2H{sub 2}O) into polymer matrices poly-β-hydroxybutyrate (PHB) with doping percentage at 1, 3, 5, and 7 (mass) were designed, fabricated and characterized. TGA and PL results indicated the Eu-complex precursor was immobilized in PHB matrix through the interaction between the Eu-complex. DSC results indicated the crystallinity of Eu/PHB films decreased with the increase of Eu-complex doping percentage. The emission spectra of the Eu-complex and Eu/PHB films recorded at room temperature exhibited the characteristic bands arising from the {sup 5}D{sub 0}/{sup 7}F{sub J}. The fact that the quantum efficiencies (η) of the doped film increased significantly revealed that the PHB matrix acts as an efficient co-sensitizer for Eu{sup 3+} ions luminescent center and therefore enhances the quantum efficiency of the emitter {sup 5}D{sub 0} level. In particular, all Eu/PHB films can be excited by visible light (410 nm), and also showed good photoluminescent properties. So the new Eu/PHB fluorescent films showed considerable promise for polymer light-emitting diode, active polymer optical fiber and biomedical analysis applications.

  12. Poly-β-hydroxybutyrate sensitizing effect on the photophysical properties of environment friendly fluorescent films containing europium complex

    International Nuclear Information System (INIS)

    Yang, Chaolong; Zhang, Pan; Zhou, Hualin; Xu, Jing; Li, Youbing; Lu, Mangeng; Lei, Lei; Zhang, Qiang; Zhang, Yi; Chen, Shaopeng

    2016-01-01

    A series of environment friendly Eu/PHB fluorescent films through doped the Eu-complex precursor Eu(TTA) 2 (Tpy-OCH 3 )(2H 2 O) into polymer matrices poly-β-hydroxybutyrate (PHB) with doping percentage at 1, 3, 5, and 7 (mass) were designed, fabricated and characterized. TGA and PL results indicated the Eu-complex precursor was immobilized in PHB matrix through the interaction between the Eu-complex. DSC results indicated the crystallinity of Eu/PHB films decreased with the increase of Eu-complex doping percentage. The emission spectra of the Eu-complex and Eu/PHB films recorded at room temperature exhibited the characteristic bands arising from the 5 D 0 / 7 F J . The fact that the quantum efficiencies (η) of the doped film increased significantly revealed that the PHB matrix acts as an efficient co-sensitizer for Eu 3+ ions luminescent center and therefore enhances the quantum efficiency of the emitter 5 D 0 level. In particular, all Eu/PHB films can be excited by visible light (410 nm), and also showed good photoluminescent properties. So the new Eu/PHB fluorescent films showed considerable promise for polymer light-emitting diode, active polymer optical fiber and biomedical analysis applications.

  13. Antagonizing STAT3 dimerization with a rhodium(III) complex.

    Science.gov (United States)

    Ma, Dik-Lung; Liu, Li-Juan; Leung, Ka-Ho; Chen, Yen-Ting; Zhong, Hai-Jing; Chan, Daniel Shiu-Hin; Wang, Hui-Min David; Leung, Chung-Hang

    2014-08-25

    Kinetically inert metal complexes have arisen as promising alternatives to existing platinum and ruthenium chemotherapeutics. Reported herein, to our knowledge, is the first example of a substitutionally inert, Group 9 organometallic compound as a direct inhibitor of signal transducer and activator of transcription 3 (STAT3) dimerization. From a series of cyclometalated rhodium(III) and iridium(III) complexes, a rhodium(III) complex emerged as a potent inhibitor of STAT3 that targeted the SH2 domain and inhibited STAT3 phosphorylation and dimerization. Significantly, the complex exhibited potent anti-tumor activities in an in vivo mouse xenograft model of melanoma. This study demonstrates that rhodium complexes may be developed as effective STAT3 inhibitors with potent anti-tumor activity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Europium, uranyl, and thorium-phenanthroline amide complexes in acetonitrile solution: an ESI-MS and DFT combined investigation.

    Science.gov (United States)

    Xiao, Cheng-Liang; Wang, Cong-Zhi; Mei, Lei; Zhang, Xin-Rui; Wall, Nathalie; Zhao, Yu-Liang; Chai, Zhi-Fang; Shi, Wei-Qun

    2015-08-28

    The tetradentate N,N'-diethyl-N,N'-ditolyl-2,9-diamide-1,10-phenanthroline (Et-Tol-DAPhen) ligand with hard-soft donor atoms has been demonstrated to be promising for the group separation of actinides from highly acidic nuclear wastes. To identify the formed complexes of this ligand with actinides and lanthanides, electrospray ionization mass spectrometry (ESI-MS) combined with density functional theory (DFT) calculations was used to probe the possible complexation processes. The 1 : 2 Eu-L species ([EuL2(NO3)](2+)) can be observed in ESI-MS at low metal-to-ligand ([M]/[L]) ratios, whereas the 1 : 1 Eu-L species ([EuL(NO3)2](+)) can be observed when the [M]/[L] ratio is higher than 1.0. However, ([UO2L(NO3)](+)) is the only detected species for the uranyl complexes. The [ThL2(NO3)2](2+) species can be observed at low [M]/[L] ratios; the 1 : 2 species ([ThL2(NO3)](3+)) and a new 1 : 1 species ([ThL(NO3)3](+)) can be detected at high [M]/[L] ratios. Collision-induced dissociation (CID) results showed that Et-Tol-DAPhen ligands can coordinate strongly with metal ions, and the coordination moieties remain intact under CID conditions. Natural bond orbital (NBO), molecular electrostatic potential (MEP), electron localization function (ELF), atoms in molecules (AIM) and molecular orbital (MO) analyses indicated that the metal-ligand bonds of the actinide complexes exhibited more covalent character than those of the lanthanide complexes. In addition, according to thermodynamic analysis, the stable cationic M-L complexes in acetonitrile are found to be in good agreement with the ESI-MS results.

  15. pH dependent photophysical studies of new europium and terbium complexes of tripodal ligand: Experimental and semiempirical approach

    International Nuclear Information System (INIS)

    Akbar, Rifat; Baral, Minati; Kanungo, B K

    2015-01-01

    The photophysical properties of adduct of a novel nonadentate tripodal ligand, 5,5′-(2-(((8-hydroxyquinolin-5-yl)methylamino)methyl)-2-methylpropane-1, 3-diyl)bis(azanediyl)bis(methylene diquinolin-8-ol, (TAME5OX), with Eu 3+ and Tb 3+ metal ions have been probed for photonics applications. The absorption spectroscopy of these complexes show remarkable spectral changes due to characteristic lanthanide transitions, which support the use of TAME5OX as a sensitive optical pH based sensor to detect Ln 3+ metal ions in biological systems. In addition, these complexes have also been shown to exhibit strong green fluorescence allowing simultaneous sensing within the visible region under physiological pH in competitive medium for both Eu 3+ and Tb 3+ ions. The intense fluorescence from these compounds were revealed to intermittently get quenched under acidic as well as basic conditions due to the photoinduced intramolecular electron transfer from excited 8-hydroxyquinoline (8-HQ) moiety to metal ion, just an opposite process. This renders these compounds the OFF–ON–OFF type of pH-dependent fluorescent sensor. The thermodynamic stability and aqueous coordination chemistry of the chelator with the said lanthanide ions have also been probed by potentiometric, UV–visible and fluorescence spectrophotometric method. TAME5OX has been found to form two protonated complexes [Ln(H 5 L)] 5+ and [Ln(H 4 L)] 4+ below pH 2.5 with both metal ions, which consecutively deprotonates through one proton process with rise of pH. The formation constants (log β 11n ) of neutral complexes have been determined to be 33.51 and 32.16 with pLn (pLn=−log[Ln 3+ ]) values of 16.14 and 19.48 for Eu 3+ and Tb 3+ ions, respectively, calculated at pH 7.4, indicating TAME5OX is a good lanthanide synthetic chelator. The emission lifetimes of the Eu 3+ and Tb 3+ complexes recorded in D 2 O and H 2 O suggest the presence of water molecules in the first coordination sphere of the metal ions. NMR

  16. pH dependent photophysical studies of new europium and terbium complexes of tripodal ligand: Experimental and semiempirical approach

    Energy Technology Data Exchange (ETDEWEB)

    Akbar, Rifat [Department of Chemistry, Sant Longowal Institute of Engineering & Technology, Longowal, Punjab 148106 (India); Baral, Minati [Department of Chemistry, National Institute of Technology Kurukshetra, Haryana 136119 (India); Kanungo, B K, E-mail: b.kanungo@gmail.com [Department of Chemistry, Sant Longowal Institute of Engineering & Technology, Longowal, Punjab 148106 (India)

    2015-11-15

    The photophysical properties of adduct of a novel nonadentate tripodal ligand, 5,5′-(2-(((8-hydroxyquinolin-5-yl)methylamino)methyl)-2-methylpropane-1, 3-diyl)bis(azanediyl)bis(methylene diquinolin-8-ol, (TAME5OX), with Eu{sup 3+} and Tb{sup 3+} metal ions have been probed for photonics applications. The absorption spectroscopy of these complexes show remarkable spectral changes due to characteristic lanthanide transitions, which support the use of TAME5OX as a sensitive optical pH based sensor to detect Ln{sup 3+} metal ions in biological systems. In addition, these complexes have also been shown to exhibit strong green fluorescence allowing simultaneous sensing within the visible region under physiological pH in competitive medium for both Eu{sup 3+} and Tb{sup 3+} ions. The intense fluorescence from these compounds were revealed to intermittently get quenched under acidic as well as basic conditions due to the photoinduced intramolecular electron transfer from excited 8-hydroxyquinoline (8-HQ) moiety to metal ion, just an opposite process. This renders these compounds the OFF–ON–OFF type of pH-dependent fluorescent sensor. The thermodynamic stability and aqueous coordination chemistry of the chelator with the said lanthanide ions have also been probed by potentiometric, UV–visible and fluorescence spectrophotometric method. TAME5OX has been found to form two protonated complexes [Ln(H{sub 5}L)]{sup 5+} and [Ln(H{sub 4}L)]{sup 4+} below pH 2.5 with both metal ions, which consecutively deprotonates through one proton process with rise of pH. The formation constants (log β{sub 11n}) of neutral complexes have been determined to be 33.51 and 32.16 with pLn (pLn=−log[Ln{sup 3+}]) values of 16.14 and 19.48 for Eu{sup 3+} and Tb{sup 3+} ions, respectively, calculated at pH 7.4, indicating TAME5OX is a good lanthanide synthetic chelator. The emission lifetimes of the Eu{sup 3+} and Tb{sup 3+} complexes recorded in D{sub 2}O and H{sub 2}O suggest the presence

  17. Lanthanide (III) complexes of 2-(N-salicylideneamino)-4-phenylthiazole

    International Nuclear Information System (INIS)

    Sasidharan, G.N.; Mohanan, K.; Lakshmi Prabha, A.N.

    2002-01-01

    Lanthanide(III) complexes of 2-(N-salicylideneamino)-4- phenylthiazole (HSAT) have been synthesised and characterised by elemental, analytical, thermogravimetric, molar conductance, UV- visible, IR and NMR spectral data. The ligand coordinates to the lanthanide(III) ion in a tridentate fashion without deprotonation, giving complexes of the type [Ln(HSAT) 2 (NO 3 ) 3 ] and [Ln(HSAT) 2 (H 2 0) 3 Cl 3 ]. The spectral data reveal that the ligand is bonded to the lanthanide ion through azomethine nitrogen, ring nitrogen and phenolic oxygen without deprotonation. The nitrate group acts in a bidentate fashion. The ligand and the metal complexes exhibit antibacterial and antifungal activities. (author)

  18. Isothiocyanato complexes of Gd(III), Tb(III), Dy(III) and Ho(III) with 2-(2'-pyridyl)benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, A; Singh, V K

    1982-01-01

    Six-coordinated complexes of the type (Ln(PyBzH)/sub 2/NCS.H/sub 2/O) (NCS)/sub 2/.nH/sub 2/O/mC/sub 2/H/sub 5/OH (Ln = Gd(III), Tb(III), Dy(III) and Ho(III), n=1-2; m=1) have been prepared from Ln(NCS)/sub 6//sup 3 -/. The room temperature magnetic moment values confirm the terpositive state of the lanthanide ions. Infrared spectra suggest the N-coordination of thiocyanate group. Electronic spectral studies of Tb(III), Dy(III) and Ho(III) complexes have been made in terms of LSJ term energies. 13 refs.

  19. Reactions of sigma-bonded organochromium(III)complexes

    International Nuclear Information System (INIS)

    Leslie, J.P. II.

    1975-12-01

    Three projects were carried out, each dealing with the kinetics and mechanism of reactions of sigma-bonded organochromium(III) complexes of the form (H 2 O) 5 CrR 2+ . Part I describes the kinetics of the reaction of dichloromethylchromium(III) ion with chromium(II) ion in aqueous acid. Part II deals with the radioexchange of 4-pyridinomethylchromium(III) ion with 51 Cr 2+ and the kinetics of formation of the organochromium species at 55 0 in 1 M H + . Part III deals with the reactions of Hg 2+ and CH 3 Hg + with a series of (H 2 O) 5 CrR 2+ complexes, in which R is an aliphatic alkyl group, a haloalkyl group, or an aralkyl group

  20. Thermodynamic study on the complexation of Trivalent actinide and lanthanide cation by N-donor ligands in homogeneous conditions; Etude thermodynamique de la complexation des ions actinide (III) et lanthanide (III) par des ligands polyazotes en milieu homogene

    Energy Technology Data Exchange (ETDEWEB)

    Miguirditchian, M

    2004-07-01

    Polydentate N-donor ligands, alone or combined with a synergic acid, may selectively extract minor actinides(III) from lanthanide(III) ions, allowing to develop separation processes of long-live radioelements. The aim of the researches carried out during this thesis was to better understand the chemical mechanisms of the complexation of f-elements by Adptz, a tridentate N-donor ligand, in homogeneous conditions. A thermodynamic approach was retained in order to estimate, from an energetic point of view, the influence of the different contributions to the reaction, and to acquire a complete set of thermodynamic data on this reaction. First, the influence of the nature of the cation on the thermodynamics was considered. The stability constants of the 1/1 complexes were systematically determined by UV-visible spectrophotometry for every lanthanide ion (except promethium) and for yttrium in a mixed solvent methanol/water in volume proportions 75/25%. The thermodynamic parameters ({delta}H{sup 0} {delta}{sup S}) of complexation were estimated by the van't Hoff method and by micro-calorimetry. The trends of the variations across the lanthanide series are compared with similar studies. The same methods were applied to the study of three actinide(III) cations: plutonium, americium and curium. The comparison of these values with those obtained for the lanthanides highlights the increase of stability of these complexes by a factor of 20 in favor of the actinide cations. This gap is explained by a more exothermic reaction and is associated, in the data interpretation, to a higher covalency of the actinide(III)-nitrogen bond. Then, the influence of the change of solvent composition on the thermodynamic of complexation was studied. The thermodynamic parameters of the complexation of europium(III) by Adptz were determined for several fractions of methanol. The stability of the complex formed increases with the percentage of methanol in the mixed solvent, owing to an

  1. Indium(III) complexes with some salicylidene aromatic Schiff bases

    International Nuclear Information System (INIS)

    Mahmoud, M.R.; Issa, I.M.; El-Gyar, S.A.

    1980-01-01

    In(III) complexes with salicylidene aromatic Schiff bases have been prepared. The nature of the complexes has been studied by microanalysis of the solid complexes, conductometric titration, uv and ir spectrophotometric measurements. The complexes are of the type 1 : 1 and 2 : 1 [Ligand : In(III)] depending upon the Schiff base. The tendency of the salicylidene Schiff base molecule towards complex formation with In(III) is found to depend largely on the strength of the intramolecular hydrogen bound established between the aldehydic OH group and C = N. Furthermore, it is concluded that these Schiff bases coordinate to In(III) as tri- or bidentate ligands depending upon the molecular structure of the Schiff base (not as monodentate ligand as previously described). The high molar absorbance of the 1 : 2 In(II) complex with salicylidene-o-hydroxyaniline I (17,800 mo1 -1 cm 2 ) can be applied for the micro determination of small amounts of Indium as low as 0.57 anti g/m1 solution. (author)

  2. Complexation of Cucurbit(7)uril with Eu(III)

    International Nuclear Information System (INIS)

    Kar, Aishwarya; Rawat, Neetika; Rao, Ankita; Tomar, B.S.; Nayak, S.K.; Ray, Alok

    2014-01-01

    Cucurbiturils (CBs) CB(n)s are macrocyclic molecules with carbonyl groups at the portals, which bind cations through ion dipole interactions and the cavity which stabilize hydrophobic moieties. The size of the portal and the volume of the interior cavities of CB(n)s are dependent on the number of glycoluril units present in CBs. CBs are widely used as supramolecular host systems in applications, such as formation of supramolecular hydrogels, drug delivery systems. Though the binding of CBs with organic guest molecules have been studied extensively where as metal complexation studies are very few. In the present work, complexation studies of Cucurbit(7)uril (with seven glycouril units, CB7) with Eu(III) were carried out using fluorescence, UV-vis spectrophotometry. The stability constant for 1:1 complex CB7-Eu(III) complex determined by monitoring the change in CB7 UV- vis absorption spectra on addition of Eu(III) was found to be 2.99 ± 0.08. The fluorescence spectra of increasing ligand to metal ratio exhibited the increase in the intensity ratio of peak at 616 and 592 which is the measure of complexation of Eu(III) with CB7 and was used to deduce the stability constant and the value (2.82 ± 0.07) obtained was in good agreement with that obtained from UV vis spectroscopy. Further, the life time of Eu(III) ion, which increased with CB7 to Eu(III) ratio, was used to deduce number of water molecules around Eu(III) metal ion which were found to decrease from 9 to 3 thereby suggesting inner sphere complexation. The stability constant of CB7 with Eu(III) is one order of magnitude less than CB5, derived in separate study by authors. The smaller cavity of CB5 (2.4 A 0 ) favors its interactions with Eu(III) ion of comparable diameter (2.16 A 0 ) leading to higher stability constant compared to CB7 (5.4 A 0 ) having larger cavity

  3. Cobalt (III) complexes as novel matrix metalloproteinase-9 inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jiyoun [Sungshin Women' s Univ., Seoul (Korea, Republic of)

    2012-04-15

    We have synthesized a series of novel MMP-9 inhibitors containing cobalt(III) complexes. The synthesized cobalt(III) complexes are effective as enzyme inhibitors and the attachment of a biphenyl group enhanced the efficiency of enzyme inhibition up to 6-fold. When compared to the reported non-hydroxamate MMP inhibitors, the synthesized complexes showed comparable in vitro potency. The enzyme assay showed that the cobalt(III) complex can disrupt the zinc binding active site of MMP-9 and is proposed to work via a ligand exchange mechanism. Since histidine residues are essential for the catalytic activity of a large percentage of enzymes and zinc finger proteins, these cobalt(III) complexes can serve as a prototype inhibitor towards various zinc containing enzymes and proteins. Matrix metalloproteinases (MMPs) are a family of zinc binding endopeptidases that play crucial roles in various physiological processes and diseases such as embryogenic growth, angiogenesis, arthritis, skin ulceration, liver fibrosis and tumor metastasis. Because of their implications in a wide range of diseases, MMPs are considered as intriguing drug targets. The majority of MMP inhibitors are organic small molecules containing a hydroxamate functionality for the zinc binding group. This hydroxamate group binds to a zinc(II) center in a bidentate fashion and creates a distorted trigonal bipyramidal geometry.

  4. Cobalt (III) complexes as novel matrix metalloproteinase-9 inhibitors

    International Nuclear Information System (INIS)

    Lee, Jiyoun

    2012-01-01

    We have synthesized a series of novel MMP-9 inhibitors containing cobalt(III) complexes. The synthesized cobalt(III) complexes are effective as enzyme inhibitors and the attachment of a biphenyl group enhanced the efficiency of enzyme inhibition up to 6-fold. When compared to the reported non-hydroxamate MMP inhibitors, the synthesized complexes showed comparable in vitro potency. The enzyme assay showed that the cobalt(III) complex can disrupt the zinc binding active site of MMP-9 and is proposed to work via a ligand exchange mechanism. Since histidine residues are essential for the catalytic activity of a large percentage of enzymes and zinc finger proteins, these cobalt(III) complexes can serve as a prototype inhibitor towards various zinc containing enzymes and proteins. Matrix metalloproteinases (MMPs) are a family of zinc binding endopeptidases that play crucial roles in various physiological processes and diseases such as embryogenic growth, angiogenesis, arthritis, skin ulceration, liver fibrosis and tumor metastasis. Because of their implications in a wide range of diseases, MMPs are considered as intriguing drug targets. The majority of MMP inhibitors are organic small molecules containing a hydroxamate functionality for the zinc binding group. This hydroxamate group binds to a zinc(II) center in a bidentate fashion and creates a distorted trigonal bipyramidal geometry

  5. Oil-soluble and water-soluble BTPhens and their europium complexes in octanol/water solutions: interface crossing studied by MD and PMF simulations.

    Science.gov (United States)

    Benay, G; Wipff, G

    2013-01-31

    Bistriazinyl-phenantroline "BTPhen" ligands L display the remarkable feature to complex trivalent lanthanide and actinide ions, with a marked selectivity for the latter. We report on molecular dynamics studies of tetrasubstituted X(4)BTPhens: L(4+) (X = (+)Et(3)NCH(2)-), L(4-) (X = (-)SO(3)Ph-), and L(0) (X = CyMe(4)) and their complexes with Eu(III) in binary octanol/water solutions. Changes in free energies upon interface crossing are also calculated for typical solutes by potential of mean force PMF simulations. The ligands and their complexes partition, as expected, to either the aqueous or the oil phase, depending on the "solubilizing" group X. Furthermore, most of them are found to be surface active. The water-soluble L(4+) and L(4-) ligands and their (L)Eu(NO(3))(3) complexes adsorb at the aqueous side of the interface, more with L(4-) than with L(4+). The oil soluble ligand L(0) is not surface active in its endo-endo form but adsorbs on the oil side of the interface in its most polar endo-exo form, as well as in its protonated L(0)H(+) and complexed (L(0))Eu(NO(3))(3) states. Furthermore, comparing PMFs of the Eu(III) complexes with and without nitric acid shows that acidifying the aqueous phase has different effects, depending on the ligand charge. In particular, acid promotes the Eu(III) extraction by L(0) via the (L(0))(2)Eu(NO(3))(2+) complex, as observed experimentally. Overall, the results point to the importance of interfacial adsorption for the liquid-liquid extraction of trivalent lanthanide and actinide cations by BTPhens and analogues.

  6. Sorption of europium by Haro river sand in aqueous solution

    International Nuclear Information System (INIS)

    Syed Moosa Hasany; Syed Javaid Khurshid

    1997-01-01

    The sorption of Eu(III) on Haro river sand has been investigated. Influences include composition of the sorptive medium, the concentration of sorbent and sorbate, and shaking time. Haro river sand can be exploited for the preconcentration and removal of europium from very dilute solutions, for the decontamination and treatment of radioactive waste water and effluents from nuclear installations. (Author)

  7. Europium sorption on zirconia at elevated temperatures: experimental study and modeling

    International Nuclear Information System (INIS)

    Eglizaud, N.; Catalette, H.

    2005-01-01

    Full text of publication follows: Direct disposal of spent nuclear fuel in deep underground repository is being considered by several countries. The waste package maintains an elevated temperature for thousands of years. As sorption is one of the main phenomenon limiting the dispersion of radionuclides in the environment, it has to be studied at elevated temperatures. Zirconia is an oxide produced by cladding oxidation which is suspected in the near field of a nuclear repository. It then could possibly be in contact with waste elements as Europium (III), the sorption of which is therefore studied on zirconia. Experiments were performed by the batch method at a solid/liquid ratio of 10 g.L-1. The sorption edges were recorded in the pH-range from 2 to 10 at 2.10 -5 mol.L -1 Eu(NO 3 ) 3 (I = 0.1 mol.L -1 KNO 3 ). An over-pressure device in an autoclave with an incorporated filtering system allowed the experiments, carbonate free, at 25 deg. C, 50 deg. C, 80 deg. C, 120 deg. C and 150 deg. C and in situ pH measurements. Filtrates were analyzed by the ICP-AES method. Sorption isotherms show an increase in the sorption phenomenon when the temperature raises. The half sorption pH decreases from 7 at 25 deg. C to 3,6 at 150 deg. C. The distribution coefficients that were obtained at elevated temperatures enriched the databases of integrated performance assessment codes. Raw data were modeled with the surface complexation theory using the double layer model (DLM). Several possible surface complexes were examined and discussed, taking into account aqueous hydrolyzed and precipitated species of Europium. A good agreement between experimental values and modeled isotherms was found at all studied temperatures. Results were consistent with a bidentate complex formed by Europium (III) on the zirconia surface. Associated formation constants were then determined with the geochemical computer code CHESS. (authors)

  8. Structural Characterization of Am(III)- and Pu(III)-DOTA Complexes.

    Science.gov (United States)

    Audras, Matthieu; Berthon, Laurence; Berthon, Claude; Guillaumont, Dominique; Dumas, Thomas; Illy, Marie-Claire; Martin, Nicolas; Zilbermann, Israel; Moiseev, Yulia; Ben-Eliyahu, Yeshayahu; Bettelheim, Armand; Cammelli, Sebastiano; Hennig, Christoph; Moisy, Philippe

    2017-10-16

    The complexation of 1,4,7,10-tetrazacyclodecane-1,4,7,10-tetraacetic acid (DOTA) ligand with two trivalent actinides (Am 3+ and Pu 3+ ) was investigated by UV-visible spectrophotometry, NMR spectroscopy, and extended X-ray absorption fine structure in conjunction with computational methods. The complexation process of these two cations is similar to what has been previously observed with lanthanides(III) of similar ionic radius. The complexation takes place in different steps and ends with the formation of a (1:1) complex [(An(III)DOTA)(H 2 O)] - , where the cation is bonded to the nitrogen atoms of the ring, the four carboxylate arms, and a water molecule to complete the coordination sphere. The formation of An(III)-DOTA complexes is faster than the Ln(III)-DOTA systems of equivalent ionic radius. Furthermore, it is found that An-N distances are slightly shorter than Ln-N distances. Theoretical calculations showed that the slightly higher affinity of DOTA toward Am over Nd is correlated with slightly enhanced ligand-to-metal charge donation arising from oxygen and nitrogen atoms.

  9. A thermodynamic study of La(III)L-alanine complexes

    International Nuclear Information System (INIS)

    Elzawawy, F.M.

    1991-01-01

    The protonation constants of L-alanine and the complex formation constants of its La(III) complexes were determined by potentiometric studies at ionic strengths 0.06, 0.1, and 0.15 mol dm -3 (NaClO 4 ) and at different temperatures 20, 27, and 35 O C. The data together with the derived thermodynamic parameters ΔH O , ΔS O , and ΔG O are reported and discussed. (author)

  10. Phosphorescent systems based on iridium(III) complexes

    NARCIS (Netherlands)

    Ulbricht, C.

    2009-01-01

    Phosphorescent iridium(III)-based complexes are experiencing a growing interest in a number of research fields. Aside from lighting and display technologies (i.e. OLEDs and LECs), they find use in various applications such as biolabeling, sensors, solar cells and water splitting. In particular, the

  11. Potentiometric studies on some ternary complexes of Nd(III), Sm(III), Gd(III) and Ho(III) with cyclohexanediaminetetraacetic acid as primary ligand

    International Nuclear Information System (INIS)

    Marathe, D.G.; Munshi, K.N.

    1983-01-01

    The formation constants of the ternary complexes of neodymium(III), samarium(III), gadlonium(III) and holmium(III) with cyclohexanediaminetetraacetic acid (CyDTA) as primary ligand and dihydroxynaphthalene (DHN), dihydroxynaphthalene-6-sulphonic acid (DHNSA) and cateechol-3,5-disulphonic acid (CDSA) as secondary ligands have been investigated by potentiometric titration technique. The secondary ligands have been investigated by potentiometric titration technique. The values of formation constants of 1:1:1 ternary chelates are reported at three different temperatures, and at a fixed ionic strength, μ = 0.1 M (NaClO 4 ). (author)

  12. Heterobimetallic gadolinium(III)-iron(III) complex of DTPA-bis(3-hydroxytyramide)

    International Nuclear Information System (INIS)

    Parac-Vogt, Tatjana N.; Kimpe, Kristof; Binnemans, Koen

    2004-01-01

    A derivative of diethylenetriamine-N,N,N',N'',N''-pentaacetic acid (DTPA), carrying two catechol functional groups has been synthesised by the reaction between DTPA-bis(anhydride) and 3-hydroxytyramine (dopamine). The ligand DTPA-bis(3-hydroxytyramide), [DTPA(HTA) 2 ], is able to form stable heterobimetallic complexes with gadolinium(III) and iron(III) ions. The gadolinium(III) occupies the internal coordination cage of DTPA formed by three nitrogens, two carboxylate and two amide oxygens, while the [Fe(NTA)(H 2 O) 2 ] (nitrilotriacetic acid, NTA) binds to catechol units by the substitution of two water ligands. The formation of polymeric species was avoided by using the tripodal NTA ligand. The heterobimetallic complex was characterised by means of visible absorption spectroscopy, electron spray ionisation-mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR) spectroscopy

  13. Kinetic Study of Iron (III) Salicyl Hydroxamate Complexes

    International Nuclear Information System (INIS)

    Ali, K.; Ashiq, U.; Ara, R.; Kazmi, R.

    2005-01-01

    The formation of Salicylhydroxamic acid iron (III) complexes were studied at different pH. The reaction at pH 8 and 6 between iron nitrate and salicylhydroxamic acid is very fast and reddish brown colour with iron at 425 nm appears within seconds i.e. within mixing time. The concentration of salicylhydroxamic acid was 20-80 times higher than the concentration of iron (III) solution in order to fulfill pseudo first order conditions. The reddish brown colour appears within mixing time and further change in colour was very slow and observed at 425 nm wave length. The rate constant at pH 8 is 0.1886 sec and at pH 6 is 1.472 sec. The sharp appearance of colour is due to formation of 1:1 and 1:2 complexes while the observed slow change in colour may be due to rearrangement of salicylhydroxamic acid from bidentate to tridentate or it may be due to the formation of 1:3 complex. In the next set of reactions the 1:1 complex of salicylhydroxamic acid iron (III) was prepared by mixing iron (III) and salicylhydroxamic acid in 1:1 mole ratio and then the formation of 1:2 complex was observed at pH 5, 4.5 and 4. The concentration of salicylhydroxamic acid solution was 2-10 times higher than the 1:1 complex of salicylhydroxamic acid iron (III) complex. The observed reactions were very fast and were not truly a first order reaction. The rate constant is 24.85 sec at pH 4.5 and 16.98 sec at pH4. The reaction of 1:1 complex with salicylhydroxamic acid at pH3 was very fast. The lamda max of iron complex is 500 nm and of final mixture is 476 nm. The reaction was assumed to be reversible. The absorbance of both species at a particular wavelength is additive. Using this property the equilibrium constant was calculated which was not constant at different ratios of 1:1 complex and salicylhydroxamic acid, which further indicate the possibility of rearrangement reaction. (author)

  14. Electrochemical behaviours of Eu(III/E(II and Ce(IV/Ce(III in H3PO4-H2O media : solvation and complexation reactions

    Directory of Open Access Journals (Sweden)

    Belqat B.

    2018-01-01

    Full Text Available Many kinds of rare earth elements (REE such as europium and cerium have been make them essential elements in many high-tech components. The electrochemical studies can be presented as an interesting indication for europium and cerium extraction from phosphoric solutions, including solvation and complexation reactions. The normal redox potentials of Eu3+/Eu2+ and Ce4+/Ce3+ systems have been determined in H3PO4-H2O media with various phosphoric acid concentration. The solvation of these elements in phosphoric media is characterized by their transfer activity coefficients "f" calculated from the corresponding normal redox potentials. The corresponding solvation increases with increasing the H3PO4 concentration. For each REE, the electrochemical properties depend on its number of charges and on its basic properties. Results suggest that solvation and complexation of REE phosphates are important in controlling REE concentration.

  15. Synthesis and reactivity of triscyclopentadienyl uranium (III) and (IV) complexes

    International Nuclear Information System (INIS)

    Berthet, J.C.

    1992-01-01

    The reactions of (RC 5 H 4 ) 3 U with R=trimethylsilylcyclopentadienyl or tertiobutylcyclopentadienyl are studied for the synthesis of new uranium organometallic compounds. Reactions with sodium hydride are first described uranium (III) anionic hydrides obtained are oxidized for synthesis of stable uranium (IV) organometallic hydrides. Stability of these compounds is discussed. Reactivity of these uranium (III) and (IV) hydrides are studied. Formation of new binuclear compounds with strong U-O and U-N bonds is examined and crystal structure are presented. Monocyclooctatetraenylic uranium complexes are also investigated

  16. Spin-crossover behavior of polymeric iron(III) complexes

    International Nuclear Information System (INIS)

    Maeda, Yonezo; Miyamoto, Makoto; Takashima, Yoshimasa; Oshio, Hiroaki

    1989-01-01

    Polymeric spin-crossover iron(III) complexes possessing poly(4-vinylpyridine), poly(N-vinylimidazole) or poly(octylmethacrylate-co-4-vinylpyridine) as ligand are prepared. In this experience enriched 57 Fe was used to get strong Moessbauer absorption. The enriched behavior of the complexes were examined by magnetic susceptibilities measurement, and Moessbauer and esr spectroscopies. Some of them show spin-state behavior over a wide range of temperature. Some of them show rapid spin-state interexchange compared to the Moessbauer time scale and others not. Spin-crossover behavior of polymeric complexes is characterized of wide spin-state transition temperature range

  17. Synthesis and reactivity of uranium (III) cyclopentadienyl complexes

    International Nuclear Information System (INIS)

    Foyentin, M.

    1987-01-01

    New uranium organometallic complexes are synthetized from the addition compound Cp U (THF). Reactions with lithium compounds, chlorides, alkynes and borohydrides. Oxidizing addition reactions are evidenced with alkyl halogenides. With a strong reducing agent, the complex Cp-UCH-Li allows the fixation and the reduction of nitrogen into ammonia. Lability of ligands bound to U (III) is evidenced, giving very reactive species and hence catalytic properties for these compounds. Catalytic hydrogenation of olefins is studied. Substitution reactions of alkyl groups of these complexes with olefins in presence or not of hydrogen or with alkyllithium are original [fr

  18. Aqueous phase complexation of Cm(III) and Cf(III) with ionizable macrocyclic ligands

    International Nuclear Information System (INIS)

    Manchanda, V.K.; Mohapatra, P.K.

    1995-01-01

    Complexation behaviour of Cm(III) and Cf(III) with 1,7-diaza-4,10,13-trioxacyclopentadecane-N,N'-diacetic acid (K21DA), 1,10-diaza-4,7,13,16-tetraoxacyclooctadecane-N,N'-diacetic acid (K22DA) and ethylene diamine N,N'- diacetic acid (EDDA) has been investigated using dinonyl naphthalene sulphonic acid (DNNS), in tetramethyl ammonium form as liquid cation exchanger. The aqueous phase complex formation constants are computed from the distribution data. Though larger complex formation constants are observed with K21DA as well as K22DA compared to those with the acyclic analog EDDA, no size correlation is observed. (author). 5 refs., 1 tab

  19. Moessbauer studies of {sup 151}Eu in europium oxalate, europium bissalen ammonium and europium benzoate

    Energy Technology Data Exchange (ETDEWEB)

    Wynter, C. I., E-mail: wynterc@ncc.edu [Nassau Community College, Department of Chemistry (United States); Ryan, D. H. [McGill University, Centre for the Physics Materials, Department of Physics (Canada); Taneja, S. P. [Maharshi Dayanand University, Department of Physics (India); May, L. [Catholic University of America, Department of Chemistry (United States); Oliver, F. W. [Morgan State University, Department of Physics (United States); Brown, D. E. [Northern Illinois University, Department of Physics (United States); Iwunzie, M. [Morgan State University, Department of Chemistry (United States)

    2005-11-15

    Although a number of europium water insoluble chelates have been prepared for several decades, the covalent nature of these compounds has never been established in any quantitative fashion. Shifts in the I.R. bands and conductivity measurements of these salts were hitherto used to qualitatively compare their molecular nature. In this communique we have used temperature coefficients of {sup 151}Eu Moessbauer spectra to determine the Debye temperatures ({theta}{sub D}) of three europium chelates: namely europium oxalate, europium bissalen ammonium (recently reported) and europium benzoate and compared their {theta}{sub D} with the measured {theta}{sub D} of the known ionic EuF{sub 3}. Additionally, the mean square amplitude (europium bissalen ammonium (133 {+-} 5 K) and lastly the europium benzoate with a {theta}{sub D} of (105 {+-} 5 K).

  20. Moessbauer spectroscopic studies of alkylammonium iron(III) complexes

    International Nuclear Information System (INIS)

    Katada, M.; Kozawa, S.; Nakajima, Y.

    2006-01-01

    Alkylammonium iron(III) complexes, [(n-C n H 2n+1 )mNH 4-m ] 3 [Fe(CN) 6 ] were prepared and studied by Moessbauer spectroscopy, XRD, and DSC. In the complexes with m=2, the temperature dependences of the area intensity of Moessbauer are correlated to the motion of alkyl chains. The temperature dependence of the complex with n=4 was linear and smaller than that of other complexes. Especially in the complex with n=6, the deviation from the linear was the largest in the complexes observed. This result is attributed to the structural difference of the complex. The complexes with n≥8 consist of two-dimensional layer structure. The temperature dependence of the area intensity was similar to each other. This means that the motion of alkyl chain in these complexes are almost the same. The values of quadrupole splitting for the complexes were larger those that of the complexes (m=1). This indicates that the form of [Fe(CN) 6 ] 3- ion is affected by the differences of the number of alkyl groups. (author)

  1. Oxidative dehydrogenation of the 2-aminomethylpyridine (EDTA) ruthenium (III) complex

    International Nuclear Information System (INIS)

    Toma, H.E.; Tsurumaki, M.

    1990-01-01

    The oxidative dehydrogenation of the 2-aminomethylpyridine (ampy) ligand coordinated to the (EDTA)RU(III) complex was investigated based on cyclic voltammetry, spectoelectrochemistry and stopped-flow kinetic measurements in aqueous solution. The reaction mechanism is consistent with the deprotonation of the ampy ligand (pk a =7.48), followed by a reversible one-electron transfer step. The intermediate species generated at this step undergoes a metal-induced electron transfer process, with k=227 s -1 , converting into the corresponding 2-iminomethylpyridine complex. (author) [pt

  2. Studies on mixed ligand complexes of lanthanide (III) ions

    International Nuclear Information System (INIS)

    Rajendran, G.; Usha Devi, K.G.

    2002-01-01

    As part of our research programme, we have prepared and characterized a few nitrato, thiocyanato and perchlorato complexes of lanthanide(III) ions with ligands, viz., a Schiff base derived from p-anisidine and vanillin and diphenyl sulphoxide. The complexes were characterized by the measurement of electrical conductances and magnetic susceptibilities, molecular mass and metal percentage and spectral analysis. The thermal decompositions were studied by TG and DTG techniques. The thiocyanato complexes were prepared by substitution method from nitrato complexes. p-Anisidine-vanillin (HDDA) and diphenyl sulphoxide (DPSO) are coordinated to the metal ion in unidentate fashion. All the anions were involved in coordination in these complexes. Thus they were found to have non- electrolytic behaviour with composition [Ln(HDDA) 2 (DPSO)X 3 ] where X = NO 3 ) or SCN perchlorato complexes were prepared from metal perchlorate as done in the case of nitrato complexes. They were found to have electrical conductance which corresponds to 1 : 1 electrolyte. Hence one of the perchlorate ions is outside the coordination sphere. The composition of this complex is found to be [Ln(HDDA) 3 (DPSO)(ClO 4 ) 2 ]ClO 4 . (author)

  3. Carbamoyl methylphosphine oxide derivatives of adamantane as americium and europium extractants

    International Nuclear Information System (INIS)

    Babain, V.A.; Alyapyshev, M.Yu.; Novakov, I.A.; Orlinson, B.S.; Savel'ev, E.N.; Shokova, Eh.A.; Serebrayannikova, A.E.; Kovalev, V.V.

    2007-01-01

    Adamantane di-1,3-carbamoyl methylphosphine oxide (CMPO) derivatives, where CMPO-groups connect with 1,3-positions of rigid adamantane platform by methylene and ethylene bridges, are synthesized, and their efficiency as extractants of americium(III) and europium(III) from nitric acid solutions is demonstrated. Distribution function of Am 3+ and Eu + during extraction from 3M HNO 3 are measured in the investigation of extraction properties. It is noted that first synthesized adamantane CMPO derivatives are more effective for the extraction of americium(III) and europium(III) from 3MHNO 3 [ru

  4. Application of europium(III) chelates-bonded silica nanoparticle in time-resolved immunofluorometric detection assay for human thyroid stimulating hormone

    International Nuclear Information System (INIS)

    Zhou Yulin; Xia Xiaohu; Xu Ye; Ke Wei; Yang Wei; Li Qingge

    2012-01-01

    Highlights: ► A rapid and ultrasensitive TSH immunoassay was developed using fluorescent silica nanoparticles-based TrIFA. ► The assay is of high sensitivity with short period time request. ► method can be potentially used at hospitals for daily clinical practice in hTSH screening. - Abstract: Eu(III) chelate-bonded silica nanoparticle was used as a fluorescent label to develop a highly sensitive time-resolved immunofluorometric assay (TrIFA) for human thyroid stimulating hormone (hTSH). The limit of detection of the assay calculated according to the 2SD method was 0.0007 mIU L −1 and became 0.003 mIU L −1 when serum-based matrix was used for calibrators, indicating that this TrIFA is comparable with the most sensitive assays. The linear range was from 0.005 to 100 mIU L −1 of hTSH with coefficient of variation between 1.9% and 8.3%. The correlation study using 204 blood spot samples from newborns showed that the results from this new method were coincident with that of the commercial dissociation-enhanced lanthanide fluorescence immunoassay (DELFIA) system, with a correlation coefficient of 0.938. The fluorescent nanoparticle label allows directly reading the fluorescent signal, omitting the signal development step required for the DELFIA system, and the whole procedure of this assay is fulfilled within 2 h. Thus, we developed a novel, sensitive, quantitative and simple nanoparticle label-based TrIFA assay, suitable for routine application in hTSH screening of neonatal hypothyroidism.

  5. Application of europium(III) chelates-bonded silica nanoparticle in time-resolved immunofluorometric detection assay for human thyroid stimulating hormone

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Yulin [Xiamen Branch of Fujian Newborn Screening Centre and Xiamen Prenatal Diagnosis Centre, Xiamen Maternal and Children' s Health Care Hospital, Xiamen, Fujian 361003 (China); Xia Xiaohu; Xu Ye; Ke Wei [Engineering Research Centre of Molecular Diagnostics Laboratory, MOE, Department of Biomedical Sciences and the Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005 (China); Yang Wei, E-mail: weiyang@xmu.edu.cn [Engineering Research Centre of Molecular Diagnostics Laboratory, MOE, Department of Biomedical Sciences and the Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005 (China); Li Qingge, E-mail: qgli@xmu.edu.cn [Engineering Research Centre of Molecular Diagnostics Laboratory, MOE, Department of Biomedical Sciences and the Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005 (China)

    2012-04-13

    Highlights: Black-Right-Pointing-Pointer A rapid and ultrasensitive TSH immunoassay was developed using fluorescent silica nanoparticles-based TrIFA. Black-Right-Pointing-Pointer The assay is of high sensitivity with short period time request. Black-Right-Pointing-Pointer method can be potentially used at hospitals for daily clinical practice in hTSH screening. - Abstract: Eu(III) chelate-bonded silica nanoparticle was used as a fluorescent label to develop a highly sensitive time-resolved immunofluorometric assay (TrIFA) for human thyroid stimulating hormone (hTSH). The limit of detection of the assay calculated according to the 2SD method was 0.0007 mIU L{sup -1} and became 0.003 mIU L{sup -1} when serum-based matrix was used for calibrators, indicating that this TrIFA is comparable with the most sensitive assays. The linear range was from 0.005 to 100 mIU L{sup -1} of hTSH with coefficient of variation between 1.9% and 8.3%. The correlation study using 204 blood spot samples from newborns showed that the results from this new method were coincident with that of the commercial dissociation-enhanced lanthanide fluorescence immunoassay (DELFIA) system, with a correlation coefficient of 0.938. The fluorescent nanoparticle label allows directly reading the fluorescent signal, omitting the signal development step required for the DELFIA system, and the whole procedure of this assay is fulfilled within 2 h. Thus, we developed a novel, sensitive, quantitative and simple nanoparticle label-based TrIFA assay, suitable for routine application in hTSH screening of neonatal hypothyroidism.

  6. Chemical species of europium (III) in ionic force media 0.02M, 0.1M, and 0.7M NaClO4 at 298 K

    International Nuclear Information System (INIS)

    Fernandez R, E.; Jimenez R, M.; Solache R, M.

    2000-01-01

    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)

  7. Luminescence studies of Sm(III) and Cm(III) complexes in NaSCN/DHDECMP extraction systems

    CERN Document Server

    Chung, D Y; Kimura, T

    1999-01-01

    Laser-induced fluorescence (LIF) studies of Sm(III) and Cm(III) complexes in the NaSCN/DHDECMP solvent extraction system were carried out. Luminescence lifetimes were measured to determine the number of water molecules coordinated to Sm(III), Tb(III), Dy(III), and Cm(III) in the sodium thiocyanate solution and in the DHDECMP phase. The hydration number of Sm(III), Tb(III), Dy(III), and Cm(III) in the sodium thiocyanate solution decreased linearly with increasing sodium thiocyanate concentration. The hydration numbers of Sm(III), Dy(III), and Cm(III) in the DHDECMP phase decreased with increasing sodium thiocyanate concentration. The water molecules in the inner coordination sphere of Sm(III) and Dy(III) extracted into the DHDECMP were not completely removed at low sodium thiocyanate concentration but decreased with increasing sodium thiocyanate concentration. However, in the case of Cm(III) extracted into the DHDECMP phase from the sodium thiocyanate solution, there was no water in the inner coordination sphe...

  8. Formation constants of Sm(III), Dy(III), Gd(III), Pr(III) and Nd(III) complexes of tridentate schiff base, 2-[(1H-benzimidazol-2-yl-methylene) amino] phenol

    International Nuclear Information System (INIS)

    Omprakash, K.L.; Chandra Pal, A.V.; Reddy, M.L.N.

    1982-01-01

    A new tridentate schiff base, 2- (1H-benzimidazol-2-yl-methylene)amino phenol derived from benzimididazole-2-carbo-xaldehyde and 2-aminophenol has been synthesised and characterised by spectral and analytical data. Proton-ligand formation constants of the schiff base and metal-ligand formation constants of its complexes with Sm(III), Dy(III), Gd(III), Nd(III) and Pr(III) have been determined potentiometrically in 50% (v/v) aqueous dioxane at an ionic strength of 0.1M (NaClO 4 ) and at 25deg C using the Irving-Rossotti titration technique. The order of stability constants (logβ 2 ) is found to be Sm(III)>Dy(III)>Gd(III)>Pr(III)>Nd(III). (author)

  9. Formation constants of Sm(III), Dy(III), Gd(III), Pr(III) and Nd(III) complexes of tridentate schiff base, 2-((1H-benzimidazol-2-yl-methylene) amino) phenol

    Energy Technology Data Exchange (ETDEWEB)

    Omprakash, K L; Chandra Pal, A V; Reddy, M L.N. [Osmania Univ., Hyderabad (India). Dept. of Chemistry

    1982-03-01

    A new tridentate schiff base, 2- (1H-benzimidazol-2-yl-methylene)amino phenol derived from benzimididazole-2-carbo-xaldehyde and 2-aminophenol has been synthesised and characterised by spectral and analytical data. Proton-ligand formation constants of the schiff base and metal-ligand formation constants of its complexes with Sm(III), Dy(III), Gd(III), Nd(III) and Pr(III) have been determined potentiometrically in 50% (v/v) aqueous dioxane at an ionic strength of 0.1M (NaClO/sub 4/) and at 25deg C using the Irving-Rossotti titration technique. The order of stability constants (log..beta../sub 2/) is found to be Sm(III)>Dy(III)>Gd(III)>Pr(III)>Nd(III).

  10. Formation of a Tc(III)-adenosine diphosphate complex

    International Nuclear Information System (INIS)

    Torres, J.; Kremer, C.; Kremer, E.

    1995-01-01

    A 99 Tc-ADP complex was prepared when KTcO 4 was reduced in aqueous medium by SnCl 2 , Na 2 S 2 O 4 , NaBH 4 or Zn in the presence of ADP in excess. The resulting solution was studied by chromatography and spectrophotometry. Electrochemical reduction and substitution on [Tc III (tu) 6 ] 3+ were investigated as alternative synthetic routes. The anionic Tc-ADP complex was isolated as a solid. Cerimetric titrations confirmed the oxidation state +3 for the central atom. IR and 1 H-NMR data showed that the purine base is bonded to the Tc central atom but not the ribose moiety. No oxo groups seemed to be directly bonded to the Tc atom. The complex is rather stable in neutral solutions. However, it decomposes to pertechnetate and TcO 2 at extreme pH values. (author). 16 refs., 2 figs., 3 tabs

  11. An isoelectronic NO dioxygenase reaction using a nonheme iron(III)-peroxo complex and nitrosonium ion.

    Science.gov (United States)

    Yokoyama, Atsutoshi; Han, Jung Eun; Karlin, Kenneth D; Nam, Wonwoo

    2014-02-18

    Reaction of a nonheme iron(III)-peroxo complex, [Fe(III)(14-TMC)(O2)](+), with NO(+), a transformation which is essentially isoelectronic with that for nitric oxide dioxygenases [Fe(III)(O2˙(-)) + NO], affords an iron(IV)-oxo complex, [Fe(IV)(14-TMC)(O)](2+), and nitrogen dioxide (NO2), followed by conversion to an iron(III)-nitrato complex, [Fe(III)(14-TMC)(NO3)(F)](+).

  12. An isoelectronic NO dioxygenase reaction using a nonheme iron(III)-peroxo complex and nitrosonium ion†

    Science.gov (United States)

    Yokoyama, Atsutoshi; Han, Jung Eun; Karlin, Kenneth D.; Nam, Wonwoo

    2014-01-01

    Reaction of a nonheme iron(III)-peroxo complex, [FeIII(14-TMC)(O2)]+, with NO+, a transformation which is essentially isoelectronic with that for nitric oxide dioxygenases [Fe(III)(O2•−) + NO], affords an iron(IV)-oxo complex, [FeIV(14-TMC)(O)]2+, and nitrogen dioxide (NO2), followed by conversion to an iron(III)-nitrato complex, [FeIII(14-TMC)(NO3)(F)]+. PMID:24394960

  13. An isoelectronic NO dioxygenase reaction using a nonheme iron(III)-peroxo complex and nitrosonium ion†

    OpenAIRE

    Yokoyama, Atsutoshi; Han, Jung Eun; Karlin, Kenneth D.; Nam, Wonwoo

    2014-01-01

    Reaction of a nonheme iron(III)-peroxo complex, [FeIII(14-TMC)(O2)]+, with NO+, a transformation which is essentially isoelectronic with that for nitric oxide dioxygenases [Fe(III)(O2•−) + NO], affords an iron(IV)-oxo complex, [FeIV(14-TMC)(O)]2+, and nitrogen dioxide (NO2), followed by conversion to an iron(III)-nitrato complex, [FeIII(14-TMC)(NO3)(F)]+.

  14. The migrant 152Eu as europium humate

    International Nuclear Information System (INIS)

    Klotz, D.

    2001-01-01

    Europium was used as a representative of the lanthanide group in the migration experiments in underground water. These 14 elements, with the atomic numbers of 58 (cerium) through 71 (lutetium) are quite similar in their chemical characteristics, and all of them will form metal-humate complexes with humic acids via proton exchange groups. Apart from the concentration, chemical composition and structure, also the particle size of these metal humates will vary strongly as it is dependent on the geochemistry and geophysics of the underground systems [de

  15. Determination of stability constants of iron(III and chromium(III-nitrilotriacetate-methyl cysteine mixed complexes by electrophoretic technique

    Directory of Open Access Journals (Sweden)

    Brij Bhushan Tewari

    2004-06-01

    Full Text Available The stability constants of Fe(III and Cr(III with methyl cysteine and nitrilotriacetate (NTA were determined by paper electrophoretic technique. Beside binary ternary complexes have also been studied, in which nitrilotriacetate and methyl cysteine acts as primary and secondary ligand, respectively. The stability constants of mixed ligand complexes metal (M-nitrilotriacetate-methyl cysteine have been found to be 5.72 plus or minus 0.09 and 5.54 plus or minus 0.11 (log K values for Fe(III and Cr(III complexes, respectively, at 35 oC and ionic strength 0.1 M.

  16. Quantum Calculations of Electron Tunneling in Respiratory Complex III.

    Science.gov (United States)

    Hagras, Muhammad A; Hayashi, Tomoyuki; Stuchebrukhov, Alexei A

    2015-11-19

    The most detailed and comprehensive to date study of electron transfer reactions in the respiratory complex III of aerobic cells, also known as bc1 complex, is reported. In the framework of the tunneling current theory, electron tunneling rates and atomistic tunneling pathways between different redox centers were investigated for all electron transfer reactions comprising different stages of the proton-motive Q-cycle. The calculations reveal that complex III is a smart nanomachine, which under certain conditions undergoes conformational changes gating electron transfer, or channeling electrons to specific pathways. One-electron tunneling approximation was adopted in the tunneling calculations, which were performed using hybrid Broken-Symmetry (BS) unrestricted DFT/ZINDO levels of theory. The tunneling orbitals were determined using an exact biorthogonalization scheme that uniquely separates pairs of tunneling orbitals with small overlaps out of the remaining Franck-Condon orbitals with significant overlap. Electron transfer rates in different redox pairs show exponential distance dependence, in agreement with the reported experimental data; some reactions involve coupled proton transfer. Proper treatment of a concerted two-electron bifurcated tunneling reaction at the Q(o) site is given.

  17. complex formation of americium (III) with humic acid

    International Nuclear Information System (INIS)

    Zhang Yingjie; Zhao Xin; Wei Liansheng; Lin Zhangji

    1998-01-01

    The presence of humic substances in natural waters will modify the migration behavior of actinides in the geosphere due to the strong reaction properties of these ligands with actinides. Therefore, the possible reactions of humic acid with actinides have been studied widely in recent years. The complex formation of Am(III) with humic acid is studied with solvent extraction technique. The experiments are performed in the pH range from 4.0 to 8.0 in 0.1 mol/kg NaClO 4 solution at ambient temperature. Experimental results show that the complex formation constants of Am(III) with humic acid are varied with the variation of pH value in solution. 1:2 complex is obtained in the experiments and the complex formation constants determined at each pH are: lgβ 1 = 6.56 +- 0.05, lgβ 2 = 10.77 +- 0.31 at pH 4.0. lgβ 1 = 7.94 +- 0.11, lgβ 2 = 11.80 +- 0.21 at pH = 5.0. lgβ 1 = 10.74 +- 0.28, lgβ 2 = 12.88 +- 0.49 at pH = 6.0. lgβ 1 = 12.85 +- 0.30, lgβ 2 = 14.80 +- 0.62 at pH = 7.0. lgβ 1 = 14.88 +- 0.48, lgβ 2 = 15.65 +- 0.69 at pH = 8.0, respectively. The dependence of the complex formation constant on pH is: lgβ 1 = 2.16 (+-0.98)pH-2.34(+-0.93),lgβ 2 1.28(+-1.04)pH+5.52(+-1.21), respectively

  18. Preparation and characterisation of mixed ligand complexes of Co(III), Fe(III) and Cr(III) containing phthalimide and phenols

    International Nuclear Information System (INIS)

    Miah, M.A.J.; Islam, M.S.; Pal, S.C.; Barma, T.K.

    1996-01-01

    Some novel mixed ligand complexes of Co(III), Fe(III) and Cr(III) containing phthalimide as primary and 2-aminophenol and 3-aminophenol as secondary ligands have been synthesized and characterised on the basis of elemental analyses, conductivity and magnetic measurements and infrared and electronic spectral studies. Complexes containing 2-aminophenol are 1:1 electrolyte in N,N dimethylformamide. Spectral studies indicate that all the complexes exhibit octahedral geometry. The complexes have the general composition; K[M(pim)/sub 2/(L)/sub 2/]; where m=Co(III), Fe(III) and Cr(III), pim-anion of phthalimamide and L=anion of 2-aminophenol and 3-aminophenol. (author)

  19. 9,10-phenanthrenesemiquinone radical complexes of ruthenium(III), osmium(III) and rhodium(III) and redox series.

    Science.gov (United States)

    Biswas, Manas Kumar; Patra, Sarat Chandra; Maity, Amarendra Nath; Ke, Shyue-Chu; Weyhermüller, Thomas; Ghosh, Prasanta

    2013-05-14

    Reactions of 9,10-phenanthrenequinone (PQ) in toluene with [M(II)(PPh3)3X2] at 298 K afford green complexes, trans-[M(PQ)(PPh3)2X2] (M = Ru, X = Cl, 1; M = Os, X = Br, 2) in moderate yields. Reaction of anhydrous RhCl3 with PQ and PPh3 in boiling ethanol affords the dark brown paramagnetic complex, cis-[Rh(PQ)(PPh3)2Cl2] (3) in good yields. Diffusion of iodine solution in n-hexane to the trans-[Os(PQ) (PPh3)2(CO)(Br)] solution in CH2Cl2 generates the crystals of trans-[Os(PQ)(PPh3)2(CO)(Br)](+)I3(-), (4(+))I3(-)), in lower yields. Single crystal X-ray structure determinations of 1·2toluene, 2·CH2Cl2 and 4(+)I3(-), UV-vis/NIR absorption spectra, EPR spectra of 3, electrochemical activities and DFT calculations on 1, 2, trans-[Ru(PQ)(PMe3)2Cl2] (1Me), trans-[Os(PQ)(PMe3)2Br2] (2Me), cis-[Rh(PQ)(PMe3)2Cl2] (3Me) and their oxidized and reduced analogues including trans-[Os(PQ)(PMe3)2(CO)(Br)](+) (4Me(+)) substantiated that 1-3 are the 9,10-phenanthrenesemiquinone radical (PQ(˙-)) complexes of ruthenium(III), osmium(III) and rhodium(III) and are defined as trans/cis-[M(III)(PQ(˙-))(PPh3)2X2] with a minor contribution of the resonance form trans/cis-[M(II)(PQ)(PPh3)2X2]. Two comparatively longer C-O (1.286(4) Å) and the shorter C-C lengths (1.415(7) Å) of the OO-chelate of 1·2toluene and 2·CH2Cl2 and the isotropic fluid solution EPR signal at g = 1.999 of 3 are consistent with the existence of the reduced PQ(˙-) ligand in 1-3 complexes. Anisotropic EPR spectra of the frozen glasses (g11 = g22 = 2.0046 and g33 = 1.9874) and solids (g11 = g22 = 2.005 and g33 = 1.987) instigate the contribution of the resonance form, cis-[Rh(II)(PQ)(PPh3)2Cl2] in 3. DFT calculations established that the closed shell singlet (CSS) solutions of 1Me and 2Me are unstable due to open shell singlet (OSS) perturbation. However, the broken symmetry (BS) (1,1) Ms = 0 solutions of 1Me and 2Me are respectively 22.6 and 24.2 kJ mole(-1) lower in energy and reproduced the experimental bond

  20. Nitrato-complexes of Y(III), La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III) and Ho(III) with 2-(2'-pyridyl) benzimidazole

    International Nuclear Information System (INIS)

    Mishra, A.; Singh, M.P.; Singh, V.K.

    1982-01-01

    The nitrato-complexes, [Y(PyBzH) 2 (NO 3 ) 2 ]NO 3 .H 2 O and Nd, Sm, Gd, Tb, Dy, Ho ; n=1-3, m=0-0.5 ; PyBzh=2-(2 -pyridyl)benzimidazole] are formed on interaction of the ligand with metal nitrates in ethanol. The electrical conductance values (116-129 ohm -1 cm 2 mol -1 ) suggest 1:1 electrolyte-nature of the complexes. Magnetic moment values of Ce(2.53 B.M.), Pr(3.62 B.M.), Nd(3.52 B.M.), Sm(1.70 B.M.), Gd(8.06 B.M.), Tb(9.44 B.M.), Dy(10.56 B.M.) and Ho(10.51 B.M.) in the complexes confirm the terpositive state of the metals. Infrared evidences are obtained for the existance of both coordinated (C 2 v) and uncoordinated (D 3 h) nitrate groups. Electronic absorption spectra of Pr(III)-, Nd(III)-, Sm(III)-, Tb(III)-, Dy(III)- and Ho(III)-complexes have been analysed in the light of LSJ terms. (author)

  1. Nitrato-complexes of Y(III), La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III) and Ho(III) with 2-(2'-pyridyl) benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, A; Singh, M P; Singh, V K

    1982-05-01

    The nitrato-complexes, (Y(PyBzH)/sub 2/(NO/sub 3/)/sub 2/)NO/sub 3/.H/sub 2/O and Nd, Sm, Gd, Tb, Dy, Ho ; n=1-3, m=0-0.5 ; PyBzh=2-(2 -pyridyl)benzimidazole) are formed on interaction of the ligand with metal nitrates in ethanol. The electrical conductance values (116-129 ohm/sup -1/cm/sup 2/mol/sup -1/) suggest 1:1 electrolyte-nature of the complexes. Magnetic moment values of Ce(2.53 B.M.), Pr(3.62 B.M.), Nd(3.52 B.M.), Sm(1.70 B.M.), Gd(8.06 B.M.), Tb(9.44 B.M.), Dy(10.56 B.M.) and Ho(10.51 B.M.) in the complexes confirm the positive state of the metals. Infrared evidences are obtained for the existance of both coordinated (C/sub 2/v) and uncoordinated (D/sub 3/h) nitrate groups. Electronic absorption spectra of Pr(III)-, Nd(III)-, Sm(III)-, Tb(III)-, Dy(III)- and Ho(III)-complexes have been analysed in the light of LSJ terms.

  2. Complex formation of americium (III) with humic acid

    International Nuclear Information System (INIS)

    Zhang Yingjie; Zhao Xin; Wen Liansheng; Lin Zhangji

    2004-01-01

    The presence of humic substances in natural waters will modify the migration behavior of actinides in the geosphere due to the strong reaction properties of these ligands with actinides. Therefore, the possible reactions of humic acid with actinides have been studied widely in recent years. The complex formation of Am (III) with humic acid is studied with solvent extraction technique in this paper. The experiments are performed in the pH range from 4.0 to 8.0 in 0.1 M NaClO 4 solution at ambient temperature. Experimental results show that the complex formation constants of Am (III) with humic acid are varied with the variation of pH value in solution. 1:2 complex is obtained in the experiments and the complex formation constants determined at each pH are: lgβ 1 =6.56±0.05, lgβ 2 =10.77±0.31 at pH=4.0; lgβ 1 =7.94±0.11, lgβ 2 =11.80±0.21 at pH=5.0; lgβ 1 =10.74±0.28, lgβ 2 =12.88±0.49 at pH=6.0; lgβ 1 =12.85±0.30, lgβ 2 =14.80±0.62 at pH=7.0; lgβ 1 =14.88±0.48, lgβ 2 =15.65±0.69 at pH=8.0, respectively. The dependence of the complex of the complex formation constant on pH is: lgβ 1 =2.16(±0.98)pH-2.34(±1.03), lgβ 2 =1.28(±1.04)pH+5.52(±1.21), respectively. (author)

  3. Impact of the mitochondrial genetic background in complex III deficiency.

    Directory of Open Access Journals (Sweden)

    Mari Carmen Gil Borlado

    Full Text Available BACKGROUND: In recent years clinical evidence has emphasized the importance of the mtDNA genetic background that hosts a primary pathogenic mutation in the clinical expression of mitochondrial disorders, but little experimental confirmation has been provided. We have analyzed the pathogenic role of a novel homoplasmic mutation (m.15533 A>G in the cytochrome b (MT-CYB gene in a patient presenting with lactic acidosis, seizures, mild mental delay, and behaviour abnormalities. METHODOLOGY: Spectrophotometric analyses of the respiratory chain enzyme activities were performed in different tissues, the whole muscle mitochondrial DNA of the patient was sequenced, and the novel mutation was confirmed by PCR-RFLP. Transmitochondrial cybrids were constructed to confirm the pathogenicity of the mutation, and assembly/stability studies were carried out in fibroblasts and cybrids by means of mitochondrial translation inhibition in combination with blue native gel electrophoresis. PRINCIPAL FINDINGS: Biochemical analyses revealed a decrease in respiratory chain complex III activity in patient's skeletal muscle, and a combined enzyme defect of complexes III and IV in fibroblasts. Mutant transmitochondrial cybrids restored normal enzyme activities and steady-state protein levels, the mutation was mildly conserved along evolution, and the proband's mother and maternal aunt, both clinically unaffected, also harboured the homoplasmic mutation. These data suggested a nuclear genetic origin of the disease. However, by forcing the de novo functioning of the OXPHOS system, a severe delay in the biogenesis of the respiratory chain complexes was observed in the mutants, which demonstrated a direct functional effect of the mitochondrial genetic background. CONCLUSIONS: Our results point to possible pitfalls in the detection of pathogenic mitochondrial mutations, and highlight the role of the genetic mtDNA background in the development of mitochondrial disorders.

  4. Complexes of o-Vanillin oxime with La(III), Ce(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III), Ho(III) and Yb(III)

    International Nuclear Information System (INIS)

    Dhar, M.L.; Gupta, V.K.; Singh, Onkar

    1988-01-01

    Ten complexes of lanthanides with o-vanillin oxime have been swynthesised and characterised. The composition of the complexes as determined by elemental and thermal analyses, infrared electronic spectral and magnetic moment studies is [Ln(C 8 H 8 NO 3 ) 3 .XH 2 O], where X=2 when Ln=La, Ce, Pr, Nd, Sm and X=3 when Ln=Gd, Dy, Tb, Ho, Yb; C 8 H 8 NO 3 - represents the anion of the ligand. (author). 16 refs., 2 figs., 2 tables

  5. 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

  6. Europium enabled luminescent nanoparticles for biomedical applications

    International Nuclear Information System (INIS)

    Syamchand, S.S.; Sony, G.

    2015-01-01

    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

  7. Sorption of Europium in zirconium silicate

    International Nuclear Information System (INIS)

    Garcia R, G.

    2004-01-01

    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 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)

  8. Anionic carbonato and oxalato cobalt(III) nitrogen mustard complexes.

    Science.gov (United States)

    Craig, Peter R; Brothers, Penelope J; Clark, George R; Wilson, William R; Denny, William A; Ware, David C

    2004-02-21

    Synthetic approaches to cobalt(III) complexes [Co(L)(L')2] containing the bidentate dialkylating nitrogen mustard N,N-bis(2-chloroethyl)-1,2-ethanediamine (L = dce) together with anionic ancilliary ligands (L') which are either carbonato (CO3(2-)), oxalato (ox2-), bis(2-hydroxyethyl)dithiocarbamato (bhedtc-), 2-pyridine carboxylato (pico-) or 2-pyrazine carboxylato (pyzc-) were investigated. Synthetic routes were developed using the related amines N,N-diethyl-1,2-ethanediamine (dee) and 1,2-ethanediamine (en). The complexes [Co(CO3)2(L)]- (L = dee 1, dce 2), [Co(ox)2(L)]- (L = dee 3, dce 4), [Co(bhedtc)2(dee)]+ 5, [Co(bhedtc)2(en)]+ 6, mer-[Co(pico)3], mer-[Co(pyzc)]3 7 and [Co(pico)2(dee)]+ 8 were prepared and were characterised by IR, UV-Vis, 1H and 13C[1H] NMR spectroscopy, mass spectrometry and cyclic voltammetry. [Co(bhedtc)2(en)]BPh4 6b and trans(O)-[Co(pico)2(dee)]ClO4 8 were characterised by X-ray crystallography. In vitro biological tests were carried out on complexes 1-4 in order to assess the degree to which coordination of the mustard to cobalt attenuated its cytotoxicity, and the differential toxicity in air vs. nitrogen.

  9. Structural basis for energy transduction by respiratory alternative complex III.

    Science.gov (United States)

    Sousa, Joana S; Calisto, Filipa; Langer, Julian D; Mills, Deryck J; Refojo, Patrícia N; Teixeira, Miguel; Kühlbrandt, Werner; Vonck, Janet; Pereira, Manuela M

    2018-04-30

    Electron transfer in respiratory chains generates the electrochemical potential that serves as energy source for the cell. Prokaryotes can use a wide range of electron donors and acceptors and may have alternative complexes performing the same catalytic reactions as the mitochondrial complexes. This is the case for the alternative complex III (ACIII), a quinol:cytochrome c/HiPIP oxidoreductase. In order to understand the catalytic mechanism of this respiratory enzyme, we determined the structure of ACIII from Rhodothermus marinus at 3.9 Å resolution by single-particle cryo-electron microscopy. ACIII presents a so-far unique structure, for which we establish the arrangement of the cofactors (four iron-sulfur clusters and six c-type hemes) and propose the location of the quinol-binding site and the presence of two putative proton pathways in the membrane. Altogether, this structure provides insights into a mechanism for energy transduction and introduces ACIII as a redox-driven proton pump.

  10. Structure of some complex halides of uranium(III)

    International Nuclear Information System (INIS)

    Volkov, V.A.; Suglobova, I.G.; Chirkst, D.E.

    1987-01-01

    Polycrystals of some halide complexes of uranium(III) were obtained and investigated by x-ray diffraction. The M 2 UCl 5 compounds (M = K, Rb) are isostructural with K 2 PrCl 5 ; RbU 2 Cl 7 is of the same type as RbDy 2 Cl 7 or KDy 2 Cl 7 . The coordination number of the uranium is 7. The M 2 UBr 5 compounds (M = K-Cs) are isostructural with Cs 2 DyCl 5 , and the coordination number of the uranium is 6. Rb 2 NaUCl 6 is a 12L-hexagonal polytype, the structural analog of Cs 2 NaCrF 6 . The most characteristic coordination number of uranium in the UHal 3 -MHal systems is 8 for Hal = F, 7 for Hal = Cl, and 6 for Hal = Br

  11. Synthesis, Structural and Antibacterial Studies of New Dithiocarbamate Complexes of Sb (III) And Bi (III)

    International Nuclear Information System (INIS)

    Nur Amirah Jamaluddin; Ibrahim Baba; Nazlina Ibrahim

    2014-01-01

    Six new dithiocarbamate complexes from three different amines, for example N-ethyl ethanol-, N-butylethyl- and N-benzylmethylamine were successfully prepared using in situ method. All complexes were characterized by elemental analysis, IR, UV-Vis, 13 C and 1 H NMR. Elemental analysis data (C, H, N and S) showed an agreement with the general formula of MCl(S 2 CNR ' R '' ) 2 , (M = Sb (III), Bi (III); R ' = ethyl, butyl and benzyl; R '' = ethanol, ethyl and methyl). The complexes had been characterized by infrared spectroscopy that showed a thioureido bands, v(C-N) in the region of 1427 - 1490 cm -1 followed by v(C-S) bands that can be seen in the region of 935 - 1060 cm -1 and v(M-S) bands existed in the region of 350 - 392 cm -1 . Maximum wavelength absorption for ultraviolet-visible spectroscopy for N-C-S group was at 254 nm which indicates π → π * transition. Data from 13 C NMR showed a signal in the region of 198.39 - 199.44 ppm that corresponded to the NCS 2 group. The crystal structure of bis(N,N ' utylethyldithiocarbamato)chloride antimony (III), SbCl (S 2 CN(C 4 H 9 )(C 2 H 5 )) 2 demonstrated a five-coordination geometry, triclinic system, space group P1 with a = 10.0141(8) Armstrong, b = 10.1394(7) Am strong, c = 11.8665(9) Armstrong, α = 67.960(2) degree, β = 87.616(2) degree and γ = 80.172(2) degree. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests were done using five dithiocarbamate complexes which are Bi Cl[S 2 CN(C 2 H 5 )(C 2 H 4 OH)) 2 , SbCl[S 2 CN(C 2 H 5 )(C 2 H 4 OH)) 2 , Bi Cl(S 2 CN(C 4 H 9 )(C 2 H 5 )) 2 , SbCl(S 2 CN(C 4 H 9 )(C 2 H 5 )) 2 , Bi Cl(S 2 CN(C 7 H 7 )(CH 3 )) 2 towards S. aureus, S. epidermidis, E. aerogenes and E. coli. It was found that all four complexes were active against S. aureus except SbCl(S 2 CN(C 2 H 5 )(C 2 H 4 OH)) 2 while Bi Cl(S 2 CN(C 7 H 7 )(CH 3 )) 2 and Bi Cl(S 2 CN(CH 3 )(C 6 H 11 )) 2 complexes were active against S. epidermidis with MIC value of 5.0 mg/ m

  12. Intramolecular interactions in a new tris-dithizonatocobalt(III) complex

    International Nuclear Information System (INIS)

    Eschwege, Karel G. von; As, Lydia van; Joubert, Chris C.; Swarts, Jannie C.; Aquino, Manuel A.S.; Cameron, T. Stanley

    2013-01-01

    Graphical abstract: Electrochemically Co(HDz) 3 (5), show three main ligand-based redox processes, two reductions and one oxidation. Ligand oxidations can be resolved into three components highlighting effective intramolecular interactions between molecular fragments; a spectroelectrochemical study of (5) highlighted spectroscopic changes during the six observed redox steps. - Highlights: • Comparative CV's of dithizone (1), PhHg(HDz) and new Co(HDz) 3 (5), is discussed. • One oxidation and two reductions per ligand and a Co III/II couple for (5) are observed. • Mono- and tris-coordinated PhHg(HDz) and (5) have stable metal thioether bonds. • Crystal structure details explain good resolution between ligand redox processes. • Spectro-electrochemistry of (5) highlights spectroscopic properties of redox products. - Abstract: The reactions between dithizone (H 2 Dz (1)) or potassium dithizonate (KHDz (3)), and [Co(H 2 O) 6 ] 2+ (6), in acetone or methanol to liberate tris-dithizonatocobalt(III), Co(HDz) 3 (5), are described. The structure of (5) was confirmed by single crystal X-ray analyses and shows bidentate coordination to Co III via S and N donor atoms for all three HDz − ligands. A comparative voltammetric and spectro-electrochemical study revealed that (1) can be oxidised in two one-electron transfer steps, to generate a disulphide first and then HDz + . In contrast, upon complexation with cobalt, the free mercaptan group of (1) becomes a stable “metal thioether”, Co-S-C, which effectively prevents disulphide formation in all three ligands of (5) upon electrochemical oxidation. As a result, each ligand of Co(HDz) 3 shows just one oxidation process. Intramolecular communication between ligands is evident because the three separate ligand-based oxidations are well resolved. Two irreversible ligand reduction steps, each consisting of three unresolved components related to each of the three ligands, were also observed. The Co II /Co III couple

  13. Analysis of gold(I/III)-complexes by HPLC-ICP-MS demonstrates gold(III) stability in surface waters.

    Science.gov (United States)

    Ta, Christine; Reith, Frank; Brugger, Joël; Pring, Allan; Lenehan, Claire E

    2014-05-20

    Understanding the form in which gold is transported in surface- and groundwaters underpins our understanding of gold dispersion and (bio)geochemical cycling. Yet, to date, there are no direct techniques capable of identifying the oxidation state and complexation of gold in natural waters. We present a reversed phase ion-pairing HPLC-ICP-MS method for the separation and determination of aqueous gold(III)-chloro-hydroxyl, gold(III)-bromo-hydroxyl, gold(I)-thiosulfate, and gold(I)-cyanide complexes. Detection limits for the gold species range from 0.05 to 0.30 μg L(-1). The [Au(CN)2](-) gold cyanide complex was detected in five of six waters from tailings and adjacent monitoring bores of working gold mines. Contrary to thermodynamic predictions, evidence was obtained for the existence of Au(III)-complexes in circumneutral, hypersaline waters of a natural lake overlying a gold deposit in Western Australia. This first direct evidence for the existence and stability of Au(III)-complexes in natural surface waters suggests that Au(III)-complexes may be important for the transport and biogeochemical cycling of gold in surface environments. Overall, these results show that near-μg L(-1) enrichments of Au in environmental waters result from metastable ligands (e.g., CN(-)) as well as kinetically controlled redox processes leading to the stability of highly soluble Au(III)-complexes.

  14. Stability constants of mixed ligand complexes of lanthanide(III) and yttrium(III) with complexone and substituted salicylic acids

    International Nuclear Information System (INIS)

    Kolhe, Vishnu; Dwivedi, K.

    1996-01-01

    Salicylic acid and substituted salicylic acids are potential antimicrobial agents. Binary complexes of salicylic acid and its substituted derivatives with lanthanide(III) and yttrium(III) metal ions have been reported. There are reports on the ternary metal complexing equilibria with some lanthanide(III) and yttrium(III) metal ions involving aminopolycarboxylic acid as one ligand and salicylic acid (SA) and other related compounds as the second ligands. Ethylene glycol bis(2-aminoethylether)- N, N, N', N'-tetraacetic acid (EGTA) is an important member of aminopolycarboxylic acid and finds many applications in medicine and biology. Recently, few ternary complexes have been reported using EGTA as ligand. In view of biological importance of simple and mixed ligand complexes EGTA, SA and DNSA (3,5-dinitrosalicylic acid), a systematic study has been undertaken for the determination of stability constant and the results are reported. (author). 6 refs., 1 fig., 2 tabs

  15. Lanthanoplatins: emissive Eu(iii) and Tb(iii) complexes staining nucleoli targeted through Pt-DNA crosslinking.

    Science.gov (United States)

    Singh, Khushbu; Singh, Swati; Srivastava, Payal; Sivakumar, Sri; Patra, Ashis K

    2017-06-01

    Two highly luminescent water-soluble heterometallic LnPt 2 complexes, [{cis-PtCl(NH 3 ) 2 } 2 Ln(L)(H 2 O)](NO 3 ) 2 (Ln = Eu (1), Tb (2)), have been designed for their selective nucleoli staining through formation of Pt-DNA crosslinks. The complexes showed significant cellular uptake and distinctive nucleoli localization through intrinsic emission from Eu III or Tb III observed through confocal fluorescence microscopy.

  16. Investigation of iron(III) complex with crown-porphyrin

    Energy Technology Data Exchange (ETDEWEB)

    Pankratov, Denis A., E-mail: pankratov@radio.chem.msu.ru; Dolzhenko, Vladimir D. [Lomonosov Moscow State University (Russian Federation); Stukan, Reonald A. [Semenov Institute of Chemical Physics, Russian Academy of Sciences (Russian Federation); Al Ansari, Yana F.; Savinkina, Elena V. [Lomonosov Moscow State Academy of Fine Chemical Technology (Russian Federation); Kiselev, Yury M. [Lomonosov Moscow State University (Russian Federation)

    2013-08-15

    Iron complex of 5-(4-(((4 Prime -hydroxy-benzo-15-crown-5)-5 Prime -yl)diazo)phenyl)-10,15, 20-triphenylporphyrin was investigated by {sup 57}Fe Moessbauer spectroscopy and EPR. Two Fe sites were identified; they give two differing signals, doublet and wide absorption in a large velocity interval. EPR spectra of solutions of the complex in chloroform at room temperature also show two signals with g = 2.064, A{sub Fe} = 0.032 cm{sup - 1}; g = 2.015, A{sub Fe} = 0.0034 cm{sup - 1}. The doublet asymmetry is studied vs. temperature and normal angle to the sample plane and gamma-beam. The isomer shift {delta} in the doublet varies from 0.25 to 0.41 mm/s in the 360-5 K temperature range, whereas quadruple splitting value is constant, {Delta} {approx} 0.65 mm/s. The relax absorption may be described as a wide singlet ({delta} = 0.30- 0.44 mm/s and {Gamma} = 2.83-3.38 mm/s); its relative area strongly depends on temperature. According to {delta}, both signals are assigned to Fe(III)

  17. Inner-sphere and outer-sphere complexes of yttrium(III), lanthanum (III), neodymium(III), terbium(III) and thulium(III) with halide ions in N,N-dimethylformamide

    International Nuclear Information System (INIS)

    Takahashi, Ryouta; Ishiguro, Shin-ichi

    1991-01-01

    The formation of chloro, bromo and iodo complexes of yttrium(III), and bromo and iodo complexes of lanthanum(III), neodymium(III), terbium(III) and thulium(III) has been studied by precise titration calorimetry in N,N-dimethylformamide (DMF) at 25 o C. The formation of [YCl] 2+ , [YCl 2 ] + , [YCl 3 ] and [YCl 4 ] - , and [MBr] 2+ and [MBr 2 ] + (M = Y, La, Nd, Tb, Tm) was revealed, and their formation constants, enthalpies and entropies were determined. It is found that the formation enthalpies change in the sequence ΔH o (Cl) > ΔH o (l), which is unusual for hard metal (III) ions. This implies that, unlike the chloride ion, the bromide ion forms outer-sphere complexes with the lanthanide(III) and yttrium(III) ions in DMF. Evidence for either an inner- or outer-sphere complex was obtained from 89 Y NMR spectra for Y(ClO 4 ) 3 , YCl 3 and YBr 3 DMF solutions at room temperature. (author)

  18. Highly sensitive sorption-luminescence determination of trace europium with preconcentration on silica chemically modified with iminodiacetic acid

    International Nuclear Information System (INIS)

    Voronina, R.D.; Zorov, N.B.

    2007-01-01

    Features of a sorption-luminescence method for the determination of trace europium were studied. The method includes the preliminary sorption of europium at pH 7.1 from solutions with silica chemically modified with iminodiacetic acid, the subsequent treatment of the sorbent with 2-thenoyltrifluoroacetone at pH 8.0, and the measurement of the intensity of luminescence of the surface three-component europium complex at 613 nm. The effect of moisture as the quencher of luminescence of the surface europium complex was studied, and techniques for its removal were proposed. Sorption in the static mode provides the detection limit of europium of 7 x 10 -5 g/ml. The calibration plot is linear in the range of two orders of magnitude of europium concentration in solutions. The relative standard deviation in the determination of 1.5 x 10 -2 μg/ml europium is 5%. In the dynamic mode of sorption from 1000 ml of an analyzed solution with the use of sorption-desorption, the detection limit of europium of 8 x 10 -7 μg/ml was attained [ru

  19. Complexation of trivalent actinides and lanthanides with hydrophilic N-donor ligands for Am(III)/Cm(III) and An(III)/Ln(III) separation; Komplexierung von trivalenten Actiniden und Lanthaniden mit hydrophilen N-Donorliganden zur Am(III)/Cm(III)- bzw. An(III)/Ln(III)-Trennung

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Christoph

    2017-07-24

    The implementation of actinide recycling processes is considered in several countries, aiming at the reduction of long-term radiotoxicity and heat load of used nuclear fuel. This requires the separation of the actinides from the fission and corrosion products. The separation of the trivalent actinides (An(III)) Am(III) and Cm(III), however, is complicated by the presence of the chemically similar fission lanthanides (Ln(III)). Hydrophilic N-donor ligands are employed as An(III) or Am(III) selective complexing agents in solvent extraction to strip An(III) or Am(III) from an organic phase loaded with An(III) and Ln(III). Though they exhibit excellent selectivity, the complexation chemistry of these ligands and the complexes formed during solvent extraction are not sufficiently characterized. In the present thesis the complexation of An(III) and Ln(III) with hydrophilic N-donor ligands is studied by time resolved laser fluorescence spectroscopy (TRLFS), UV/Vis, vibronic sideband spectroscopy and solvent extraction. TRLFS studies on the complexation of Cm(III) and Eu(III) with the Am(III) selective complexing agent SO{sub 3}-Ph-BTBP (tetrasodium 3,3{sup '},3'',3{sup '''}-([2,2{sup '}-bipyridine]-6,6{sup '}-diylbis(1,2,4-triazine-3,5,6-triyl)) tetrabenzenesulfonate) revealed the formation of [M(SO{sub 3}-Ph-BTBP){sub n}]{sup (4n-3)-} complexes (M = Cm(III), Eu(III); n = 1, 2). The conditional stability constants were determined in different media yielding two orders of magnitude larger β{sub 2}-values for the Cm(III) complexes, independently from the applied medium. A strong impact of ionic strength on the stability and stoichiometry of the formed complexes was identified, resulting from the stabilization of the pentaanionic [M(SO{sub 3}-Ph-BTBP){sub 2}]{sup 5-} complex with increasing ionic strength. Thermodynamic studies of Cm(III)-SO{sub 3}-Ph-BTBP complexation showed that the proton concentration of the applied medium impacts

  20. Dramatic improvement in photostability of luminescent Eu(III) complexes with tetraphenylimidodiphosphinate ligand

    International Nuclear Information System (INIS)

    Zheng, Wei; Li, Shu-Jing; Li, Cheng-Hui; Zheng, You-Xuan; You, Xiao-Zeng

    2014-01-01

    In this paper, we synthesized and characterized a new Eu(III) tetraphenylimidodiphosphinate complex with dimethyl sulfoxide (DMSO) as co-ligand. Moreover, we compared the photostability of a series of Eu(III) complexes containing tetraphenylimidodiphosphinate ligands, Eu(tpip) 3 , Eu(tpip) 3 Phen, Eu(tpip) 3 DMSO, with their analogs of 1,3-dibenzoylmethanate, Eu(dbm) 3 ∙2H 2 O, Eu(dbm) 3 Phen, Eu(dbm) 3 (DMSO) 2 . We found that the photostability of the luminescent Eu(III) complexes was significantly improved upon substitution of the 1,3-diketones with tetraphenylimidodiphosphinate ligands. -- Highlights: • We synthesized and characterized a new Eu(III) tetraphenylimidodiphosphinate complexes with dimethyl sulfoxide. • We compared the photostability of Eu(III) complex with tetraphenylimidodiphosphinate and 1,3-dibenzoylmethanate ligands. • The photostability is significantly improved in Eu(III) complexes with tetraphenylimidodiphosphinate ligands

  1. Study of Stoichiometry and Stability of some Fe(III)-Amino Acid Complexes

    International Nuclear Information System (INIS)

    Latif, S.; Shirin, K.; Nisar, S.; Zahida, T. M.

    2005-01-01

    The complexation of ferric with three amino acids (Glycine, Glutamic acid and Aspartic acid) was studied spectrophotometrically and potentiometrically at pH 5.0 and in aqueous medium. The stoichiometry was calculated spectrophotometrically using mole ratio method and is found to be ML3 for Fe (III)-Glycine and ML2 for Fe (III)-Glutamate for Fe (III)-Glutamate and Aspartate complex. The stabilities of these complexes were calculated spectrophotometrically and potentiometrically. The experimental results of potentiometric titrations were treated by well known computer program B EST . The values were further refined till least sigma fit i.e. 0.03. The complexes were not formed under normal conditions. Each complex was studied at more than one wavelength and no kmax was obtained because Fe (III) solution and the complexes absorb in similar wavelength region. The formation constants of all these complexes are not very high shows weak complexation of Fe (III) with these amino acids. (author)

  2. Absorption spectra analysis of hydrated uranium(III) complex chlorides

    Science.gov (United States)

    Karbowiak, M.; Gajek, Z.; Drożdżyński, J.

    2000-11-01

    Absorption spectra of powdered samples of hydrated uranium(III) complex chlorides of the formulas NH 4UCl 4 · 4H 2O and CsUCl 4 · 3H 2O have been recorded at 4.2 K in the 4000-26 000 cm -1 range. The analysis of the spectra enabled the determination of crystal-field parameters and assignment of 83 and 77 crystal-field levels for the tetrahydrate and trihydrate, respectively. The energies of the levels were computed by applying a simplified angular overlap model as well as a semiempirical Hamiltonian representing the combined atomic and crystal-field interactions. Ab initio calculations have enabled the application of a simplified parameterization and the determination of the starting values of the AOM parameters. The received results have proved that the AOM approach can quite well predict both the structure of the ground multiplet and the positions of the crystal-field levels in the 17 000-25 000 cm -1 range, usually obscured by strong f-d bands.

  3. Effect of pH on stability constants of Am(III)- and Cm(III)- humate complexes

    International Nuclear Information System (INIS)

    Samadfam, Mohammad; Jintoku, Takashi; Sato, Seichi; Ohashi, Hiroshi; Mitsugashira, Toshiaki; Hara, Mitsuo; Suzuki, Yoshimitsu

    1999-01-01

    The apparent stability constants of Am(III)- and Cm(III)-humate complexes were determined by dialysis method at ionic strength 0.1 in the pH range from 3.3 to 5.7 under N 2 bubbling. The Am(III) and Cm(III) loadings were about 10 -7 and 10 -10 mol/dm 3 . The concentrations of Am-241 and Cm-242 tracers were measured by α-spectrometry. It was found that the apparent stability constants were almost identical for both the Am(III)-humate and Cm(III)-humate complexes. The apparent stability constants showed a small pH-dependence, increasing from 10 4.6 at pH 3.3 to 10 5.1 at pH 5.7. The ionization of acidic functional groups of humic acid is possibly the primary factor. Above pH 6, the dialysis membrane was no langer permeable to Am(III) and Cm(III) ions and the apparent stability constant could not be experimentally obtained. The apparent stability constants between pH 6 and pH 8.5 were evaluated by considering that both binary metal-humate and ternary metal-hydroxo-humate complexes exist at pHs above 6. It was assumed that mono-hydroxo-humate complex Am(OH)HA and Cm(OH)HA are the major ternary complexes that exist below pH 9. The overall stability constants for Am(III)- and Cm(III)-humate complexes increased from 10 5.7 at pH 6 to 10 7.2 at pH 8. This implies that the formation of metal-hydroxo-humate species is preferred over the formation of hydroxide species. The apparent overall stability constants can be easily incorporated into geochemical modeling of trivalent actinide migration. The results of the present study show that the apparent stability constants determined experimentally at pH≤6 do not represent the complexation properties at higher pHs and the formation of ternary complexes should be considered in speciation calculations of radionuclides at terrestrial environment. (J.P.N.)

  4. Studies of Some Lanthanide(III Nitrate Complexes of Schiff Base Ligands

    Directory of Open Access Journals (Sweden)

    Kishor Arora Mukesh Sharma

    2009-01-01

    Full Text Available The studies of 16 new lanthanide(III nitrate complexes of Schiff base ligands are discussed. Schiff bases were obtained by the condensation of 2–methyl–4–N,N–bis–2' –cyanoethyl aminobenzaldehyde with aniline and 3 different substituted anilines. Lanthanide(III nitrates, viz. gadolinium(III nitrate, lanthanum(III nitrate, samarium(III nitrate and cerium(III nitrate were chosen to synthesize new complexes. The complexes were characterized on the basis of physicochemical studies viz. elemental analysis, spectral, viz. IR and electronic spectral and magnetic studies. TGA studies of some of the representative complexes were also done. Some of the representative complexes were also screened for the anti microbial studies.

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

    International Nuclear Information System (INIS)

    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. 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

  6. Blue phosphorescent mono-cyclometalated iridium(III) complexes

    Energy Technology Data Exchange (ETDEWEB)

    Ham, Ho Wan; Yang, Yoon A; Kim, Young Sik [Hongik University, Seoul (Korea, Republic of)

    2010-12-15

    New deep blue phosphorescent iridium(III) complexes comprised of one cyclometalate, two phosphines trans to each other and two cis-ancillary ligands, such as Ir(F{sub 2}Meppy)(PPh{sub 2}Me){sub 2}(H)(Cl), Ir(F{sub 2}Meppy)(PPh{sub 2}Me){sub 2}(H)(NCMe){sup +}, and Ir(F{sub 2}Meppy)(PPh{sub 2}Me){sub 2}(H)(CN), [F{sub 2}Meppy = 2-(2', 4'- difluorophenyl)-4-methyl-pyridine] were synthesized and studied to tune the phosphorescence wavelength to the deep blue region and to enhance the luminescence efficiencies. We investigated the strong field effects of ancillary ligands to gain insight into the factors responsible for the emission color change and the different luminescence efficiency. Reducing the molecular weight of the phosphine ligand with PPh{sub 2}Me leads to more efficient deep-blue organic light-emitting devices (OLED) by thermal processing instead of through solution processing. The electron-withdrawing difluoro group substituted on the phenyl ring, the electron-donating methyl group on the pyridyl ring, and the cyano strong field ancillary ligand increased the HOMO-LUMO gap and achieved a hypsochromic shift in the emission color. As a result, the maximum emission spectra of Ir(F{sub 2}Meppy)-(PPh{sub 2}Me){sub 2}(H)(Cl), Ir(F{sub 2}Meppy)(PPh{sub 2}Me){sub 2}(H)(NCMe){sup +}, and Ir(F{sub 2}Meppy)(PPh{sub 2}Me){sub 2-}(H)(CN) were in the ranges of 440.5, 437, 436 nm, respectively.

  7. Blue phosphorescent mono-cyclometalated iridium(III) complexes

    International Nuclear Information System (INIS)

    Ham, Ho Wan; Yang, Yoon A; Kim, Young Sik

    2010-01-01

    New deep blue phosphorescent iridium(III) complexes comprised of one cyclometalate, two phosphines trans to each other and two cis-ancillary ligands, such as Ir(F 2 Meppy)(PPh 2 Me) 2 (H)(Cl), Ir(F 2 Meppy)(PPh 2 Me) 2 (H)(NCMe) + , and Ir(F 2 Meppy)(PPh 2 Me) 2 (H)(CN), [F 2 Meppy = 2-(2', 4'- difluorophenyl)-4-methyl-pyridine] were synthesized and studied to tune the phosphorescence wavelength to the deep blue region and to enhance the luminescence efficiencies. We investigated the strong field effects of ancillary ligands to gain insight into the factors responsible for the emission color change and the different luminescence efficiency. Reducing the molecular weight of the phosphine ligand with PPh 2 Me leads to more efficient deep-blue organic light-emitting devices (OLED) by thermal processing instead of through solution processing. The electron-withdrawing difluoro group substituted on the phenyl ring, the electron-donating methyl group on the pyridyl ring, and the cyano strong field ancillary ligand increased the HOMO-LUMO gap and achieved a hypsochromic shift in the emission color. As a result, the maximum emission spectra of Ir(F 2 Meppy)-(PPh 2 Me) 2 (H)(Cl), Ir(F 2 Meppy)(PPh 2 Me) 2 (H)(NCMe) + , and Ir(F 2 Meppy)(PPh 2 Me) 2- (H)(CN) were in the ranges of 440.5, 437, 436 nm, respectively.

  8. 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...

  9. Cyclic Voltammetric Study of Complexes of Fe (III) with Saponins Isolated from Cicer aritinum and Glycyrrhizin

    International Nuclear Information System (INIS)

    Khan, S.S.; Kazmi, S.A.; Anwar, H

    2013-01-01

    Cyclic voltammetric study was used to analyze three new saponins (isolated from the seeds of Cicer aritinum) along with a known saponin soyasaponin I and beta sitosterol glycoside isolated saponins as well as glycyrrhizin. These studies were carried out in aqueous medium at Glassy carbon (GCE) electrode vs. AgCl reference electrode. Results revealed that the voltammograms of Fe(III) with isolated saponins are irreversible while that of Fe(III)-glycyrrhizin complex is reversible. Even though precise Eo values of their Fe(III) complex could not be determined, it is clearly indicated that Fe(III) forms complexes with these saponins. The ability to form strong complexes with Fe(III) therefore reduces the availability of Fe(III) by saponins. (author)

  10. 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.

  11. Lanthanum(III) and praseodymium(III) complexes with bidentate and tetradentate Schiff base ligands containing indole ring

    International Nuclear Information System (INIS)

    Rai, Anita; Sengupta, Soumitra Kumar; Pandey, Om Prakash

    2000-01-01

    Complexes of lanthanum(III) and praseodymium(III) with Schiff bases, prepared from isatin with aniline, 4-chloroaniline, 2- bromoaniline, 2-nitroaniline (Hl), ethylenediamine, o- phenylenediamine and 4-methyl-o-phenylenediamine (H 2 L') have been synthesised and their physico-chemical properties investigated using elemental analysis, molar conductivities, magnetic susceptibility measurements and spectral (visible, infrared and 1 H NMR) data. The Schiff bases HL bind in a bidentate manner while schiff bases H 2 L' bind in a tetradentate manner. The probable structures of the complexes are proposed. (author)

  12. Spectral intensities and bonding parameters for some praseodymium(III) and neodymium(III) complexes with benzimidazoles

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, P C; Ojha, C K; Mittal, S; Joshi, G K

    1988-09-01

    The electronic spectral intensity parameters (Judd-Ofelt; Tsub(lambda)) calculated from absorption spectral data for the complexes of praseodymium(III) and neodymium(III) nitrates with benzimidazole and 2-methyl-, 2-ethyl- and 2-n-propyl-benzimidazoles are reported. The conductance of these derivatives in dimethylformamide suggests 1:1 electrolytic nature. The infrared spectral data indicate the presence of Csub(2v) as well Dsub(2h)-nitrate ions in the complexes. The correlation of the intensity of hypersensitive transitions with bonding (nephelauxetic ratio and degree of covalency) parameters are also reported. (author). 13 refs., 2 tables.

  13. Mixed ligand complexes of some of the rare earths. La(III)-, Pr(III)- or Nd-(III)-CDTA-Hydroxy Acids

    Energy Technology Data Exchange (ETDEWEB)

    Rana, H S; Tandon, J P [Rajasthan Univ., Jaipur (India). Chemical Labs.

    1975-11-01

    Biligand complexes of the 1:1 Ln(III)-1,2-diaminocyclohexane-tetraacetic acid (CDTA) chelate with hydroxy acids (where hydroxy acids = salicylic acid (SA); Sulphosalicylic acid (SSA) and 8-hydroxyquinoline-5-sulphonic acid (HQSA)) have been investigated by potentiometric titration. Their formation constants have been calculated (..mu..=0.1M-KNO/sub 3/; and t=30+-1 deg C) as 4.60 +-0.03, 5.46+-0.03, 5.87+-0.05; 3.12+-0.04, 3.95+-0.05, 4.42+-0.07; 2.73+-0.06, 3.45+-0.05 and 3.90+-0.08 for Ln(III)-CDTA-SA,-SSA, and -HQSA respectively (where Ln=La, Pr or Nd). The value of log Ksub(MAB) follows the order: La(III)).

  14. Preparation and luminescent properties of the novel polymer-rare earth complexes composed of Poly(ethylene-co-acrylic acid) and Europium ions

    Science.gov (United States)

    Wu, Yuewen; Hao, Haixia; Wu, Qingyao; Gao, Zihan; Xie, Hongde

    2018-06-01

    A series of novel polymer-rare earth complexes with Eu3+ ions have been synthesized and investigated successfully, including the binary complexes containing the single ligand poly(ethylene-co-acrylic acid) (EAA) and the ternary complexes using 1,10-phenanthroline (phen), dibenzoylmethane (DBM) or thenoyltrifluoroacetone (TTA) as the second ligand. Their structures have been characterized by Fourier transform infrared spectroscopy (FT-IR), elemental analysis and X-ray diffraction (XRD), which confirm that both EAA and small molecules participate in the coordination reaction with rare earth ions, and they can disperse homogeneously in the polymer matrixes. Both ultraviolet-visible (UV-vis) absorption and photoluminescence tests for the complexes have been recorded. The relationship between fluorescence intensity of polymer-rare earth complexes and the quantity of ligand EAA has been studied and discussed. The films casted from the complexes solution can emit strong characteristic red light under UV light excitation. All these results suggest that the complexes possess potential application as luminescent materials.

  15. Thermodynamics of U(VI) and Eu(III) complexation by unsaturated carboxylates

    Energy Technology Data Exchange (ETDEWEB)

    Rawat, Neetika; Bhattacharyya, A. [Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Tomar, B.S., E-mail: bstomar@barc.gov.in [Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Ghanty, T.K. [Theoretical Chemistry Section, Bhabha Atomic Research Centre, Mumbai 400085 (India); Manchanda, V.K. [Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2011-05-10

    Highlights: {yields} {Delta}H and log K determined for U(VI) and Eu(III) complexes with maleate and fumarate. {yields} log K and coordination environment of Eu(III) complexes has been studied by TRFS. {yields} Higher log K of U(VI) complexes than Eu(III) complexes is due to higher entropy. {yields} Plot of log K vs log K{sub P} suggest charge polarization in fumarate complexes. {yields} Ab initio calculations support charge polarization in fumarate complexes. - Abstract: The thermodynamic parameters ({Delta}G, {Delta}H and {Delta}S) of complexation of U(VI) and Eu(III) by unsaturated dicarboxylic acids, namely, maleic and fumaric acid, has been determined by potentiometric and microcalorimetric titrations at fixed ionic strength (I = 1.0 M) and temperature (298 K). The results show formation of 1:1 complexes by both the ligands with Eu(III). In the case of U(VI), maleate forms both 1:1 and 1:2 complexes, while only 1:1 complex was formed with fumarate. The fluorescence emission spectra of Eu(III)-dicarboxylate solutions at varying ligand to metal ratio were also used to obtain their stability constants. In addition, the fluorescence lifetimes reveal higher dehydration of Eu(III)-maleate compared to Eu(III)-fumarate which corroborates the {Delta}S values. The thermodynamic quantities suggest charge polarization effects in the case of U(VI) and Eu(III) complexes of fumarate, which is further corroborated by theoretical calculations. For the same ligand, U(VI) complexes were found to be more stable which was mainly due to higher entropy term.

  16. Fluorescence properties of europium and samarium. beta. -diketonates and their use in fluorometry

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H; Hiraki, K; Nishikawa, Y [Kinki Univ., Higashi-Osaka, Osaka (Japan). Faculty of Science and Technology

    1981-01-01

    Several europium and samarium ..beta..-diketonates (tta, ntfa, bfa) complexed with 1, 10-phenanthroline, or with trioctylphosphine oxide (topo) were synthesized. The fluorescence properties of these compounds in benzene or hexane have been studied. Absorption and fluorescence spectra, fluorescence quantum yield, fluorescence sensitivity index (F.S.I.), and fluorescence lifetime were measured. From the measurement of fluorescence lifetime of the ..beta..-diketonates, the velocity of radiative process (k sub(f)/phi sub(f)) has almost the same value for benzene and hexane solvent. The red fluorescence (Em. max. : 619 nm) of Eu(III) in these chelates is attributed to transitions from /sup 5/D/sub 0/ ..-->.. /sup 7/F/sub 2/ levels of this ion, and the three-band spectrum (Em. max. : 569 nm, 606 nm, 650 nm) indicates the transitions from the /sup 4/G sub(5/2) ..-->.. /sup 6/H sub(5/2), /sup 4/G sub(5/2) ..-->.. /sup 6/H sub(7/2), and /sup 4/G sub(5/2) ..-->.. /sup 6/H sub(9/2) levels of Sm(III), respectively. These spectra are not changed by any solvents and ligands. From the results, the fluorescence of the ..beta..-diketonates in organic solvent has been attributed to m* ..-->.. m luminescence transition. The complexes of Eu(III) and Sm(III) show radiative transition within orbitals, composed exclusively of 4f orbitals of rare earth ions (m* ..-->.. m radiative transition). Fluorinated ligands show better sensitivity than unfluorinated ligands, and the best sensitivity is obtained with TTA-phen system, and/or TTA-topo system for the spectrofluorometric determination of the two metals. In the case of Eu determination, 619 nm emission wavelength is used (the determinable range : 0.2 -- 10 ppb Eu), and in the case of Sm determination, 650 nm emission wavelength is adopted (the determinable range : 0.1 -- 1 ppm Sm), because of much higher sensitivity than the other two peaks (569, 606 nm) without interference from europium complex.

  17. 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.

  18. Optical and magnetization studies on europium based iron pnictides

    International Nuclear Information System (INIS)

    Zapf, Sina Maria Ute

    2015-01-01

    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 2 (As 1-x P x ) 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 2 As 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.

  19. Crystal structure and luminescence of complexes of Eu(III) and Tb(III) with furan-2,5-dicarboxylate

    NARCIS (Netherlands)

    Akerboom, S.; Fu, W.T.; Lutz, M.; Bouwman, E.

    2012-01-01

    Four new Ln(III) complexes (Ln = Eu, Tb) with furan-2,5-dicarboxylic acid (H2FDA) as a ligand have been synthesized and characterized in the solid state. Luminescence studies indicate that the compounds exhibit line-like luminescence characteristic of the lanthanide centre upon excitation in the

  20. 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)

  1. Impact of Fe(III)-OM complexes and Fe(III) polymerization on SOM pools reactivity under different land uses

    Science.gov (United States)

    Giannetta, B.; Plaza, C.; Zaccone, C.; Siebecker, M. G.; Rovira, P.; Vischetti, C.; Sparks, D. L.

    2017-12-01

    Soil organic matter (SOM) protection and long-term accumulation are controlled by adsorption to mineral surfaces in different ways, depending on its molecular structure and pedo-climatic conditions. Iron (Fe) oxides are known to be key regulators of the soil carbon (C) cycle, and Fe speciation in soils is highly dependent on environmental conditions and chemical interactions with SOM. However, the molecular structure and hydrolysis of Fe species formed in association with SOM is still poorly described. We hypothesize the existence of two pools of Fe which interact with SOM: mononuclear Fe(III)-SOM complexes and precipitated Fe(III) hydroxides. To verify our hypothesis, we investigated the interactions between Fe(III) and physically isolated soil fractions by means of batch experiments at pH 7. Specifically, we examined the fine silt plus clay (FSi+C) fraction, obtained by ultrasonic dispersion and wet sieving. The soil samples spanned several land uses, including coniferous forest (CFS), grassland (GS), technosols (TS) and agricultural (AS) soils. Solid phase products and supernatants were analyzed for C and Fe content. X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) analysis were also performed. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was used to assess the main C functional groups involved in C complexation and desorption experiments. Preliminary linear combination fitting (LCF) of Fe K-edge extended X-ray absorption fine structure (EXAFS) spectra suggested the formation of ferrihydrite-like polymeric Fe(III) oxides in reacted CFS and GS samples, with higher C and Fe concentration. Conversely, mononuclear Fe(III) OM complexes dominated the speciation for TS and AS samples, characterized by lower C and Fe concentration, inhibiting the hydrolysis and polymerization of Fe (III). This approach will help revealing the mechanisms by which SOM pools can control Fe(III) speciation, and will elucidate how both Fe(III

  2. Synthesis, characterization, antiplasmodial and antitrypanosomal activity of some metal(III complexes of sulfadiazine

    Directory of Open Access Journals (Sweden)

    P.A. Ajibade

    2008-08-01

    Full Text Available The Fe(III, Ru(III, Rh(III, and Cr(III complexes of 4-amino-N-(2-pyrimidinylbenzene sulfonamide (sulfadiazine have been synthesized and characterized by elemental analysis, electronic and IR spectroscopy, conductance and room temperature magnetic susceptibility measurements. Sulfadiazine acts as a bidentate ligand through the sulfonamido and the pyrimidinic N-atoms. The compounds are non-electrolytes and the electronic spectra are consistent with the proposed octahedral geometry around the metal ions. The complexes were tested for in vitro activity against cultures of the resistant strains of Plasmodium falciparum, tripamastigotes T. b. rhodesiense and amastigotes L. donovani to determine their antiprotozoal activities. The Fe(III complex is more active than the other complexes against the parasitic protozoa.

  3. Level III Reliability methods feasible for complex structures

    NARCIS (Netherlands)

    Waarts, P.H.; Boer, A. de

    2001-01-01

    The paper describes the comparison between three types of reliability methods: code type level I used by a designer, full level I and a level III method. Two cases that are typical for civil engineering practise, a cable-stayed subjected to traffic load and the installation of a soil retaining sheet

  4. Lanthanide(III) complexes with tridentate Schiff base ligand ...

    African Journals Online (AJOL)

    The X-ray study reveals isotopic Nd/Sm binuclear structures were each metal ion is nine-coordinated in the same fashion. Both metal centers have distorted tricapped trigonal prism geometry, with the Schiff base acting as tridentate ligand. The DPPH· radical scavenging effects of the Schiff base ligand and its Ln(III) ...

  5. Synthesis and characterization of a Schiff base Cobalt (III) complex ...

    African Journals Online (AJOL)

    Schiff base molecule acts as tridentate ligand to form two five-membered chelate rings with the Co(III) ion. In the crystal structure three meridionally arranged nitrogen atoms from three azide ligands complete a distorted octahedral geometry around the metal center. The distortion from an ideal octahedron is evident from the ...

  6. Mass spectrometric investigation of fluorated europium. beta. -diketonates. [Electrons

    Energy Technology Data Exchange (ETDEWEB)

    Khomenko, V.S.; Lozinskij, M.O.; Fialkov, Yu.A.; Rasshinina, T.A.; Suboch, V.P. (AN Belorusskoj SSR, Minsk. Inst. Fiziki; AN Ukrainskoj SSR, Kiev. Inst. Organicheskoj Khimii)

    Ternary complexes of europium with two organic ligands - fluorated ..beta..-diketone and organic base - in the aqueous phase at electron shock are investigated; regroupings that take place in them are established. Mass-spectrometric investigation has shown that complexes with ..beta..-diketones, containing in oxygen atom in a fluorated radical, eliminate stable molecules of difluorophosgen, CoF/sub 2/. For the complexes studied under the above conditions the Co molecule elimination is also typical which is accompanied by the formation of ions with a metal-carbon bond.

  7. Mass spectrometric investigation of fluorated europium β-diketonates

    International Nuclear Information System (INIS)

    Khomenko, V.S.; Lozinskij, M.O.; Fialkov, Yu.A.; Rasshinina, T.A.; Suboch, V.P.; AN Ukrainskoj SSR, Kiev. Inst. Organicheskoj Khimii)

    1983-01-01

    Ternary complexes of europium with two organic lidands - fluorated β-diketone and organic base - in the aqueous phase at electron shock are investigated; regroupings that take place in them are established. Mass-spectrometric investigation has shown that complexes with β-diketones, containing in oxygen atom in a fluorated radical, eliminate stable molecules of difluorophosgen, CoF 2 . For the complexes studied under the above conditions the Co molecule elimination is also typical which is accompanied by the formation of ions with a metal-carbon bond

  8. 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)

  9. Equilibrium Fe isotope fractionation between inorganic aqueous Fe(III) and the siderophore complex, Fe(III)-desferrioxamine B

    DEFF Research Database (Denmark)

    Dideriksen, Knud; Baker, Joel A.; Stipp, Susan Louise Svane

    2008-01-01

    be controlled by isotope fractionation between the free and complexed iron.We have determined the equilibrium Fe isotope fractionation induced by organic ligand activity in experiments with solutions having co-existing inorganic Fe(III) species and siderophore complexes, Fedesferrioxamine B (at pH 2). The two......-type fractionation during precipitation, this experiment yielded an isotope fractionation factor of a56Fesolution-solid=1.00027. Calculations based on these results indicate that isotopic re-equilibration is unlikely to significantly affect our determined equilibrium Fe isotope fractionation between inorganically...... and organically complexed Fe. To determine the equilibrium Fe isotope fractionation between inorganically and organically bound Fe(III), experiments with variable proportions of inorganic Fe were carried out at 25 °C. Irrespective of the proportion of inorganic Fe, equilibrium fractionation factors were within...

  10. Synthesis and Characterization of Chromium (III) Complexes with L-Glutamic Acid, Glycine and LCysteine

    OpenAIRE

    Kun Sri Budiasih; Chairil Anwar; Sri Juari Santosa; Hilda Ismail

    2013-01-01

    Some Chromium (III) complexes were synthesized with three amino acids: L Glutamic Acid, Glycine, and L-cysteine as the ligands, in order to provide a new supplement containing Cr(III) for patients with type 2 diabetes mellitus. The complexes have been prepared by refluxing a mixture of Chromium(III) chloride in aqueous solution with L-glutamic acid, Glycine, and L-cysteine after pH adjustment by sodium hydroxide. These complexes were characterized by Infrared and Uv-Vis s...

  11. Identification of Lanthanide(III) Luminophores in Magnetic Circularly Polarized Luminescence Using Raman Optical Activity Instrumentation

    Czech Academy of Sciences Publication Activity Database

    Wu, Tao; Kapitán, J.; Andrushchenko, Valery; Bouř, Petr

    2017-01-01

    Roč. 89, č. 9 (2017), s. 5043-5049 ISSN 0003-2700 R&D Projects: GA ČR(CZ) GJ16-08764Y; GA ČR GA15-09072S; GA ČR(CZ) GA16-05935S Institutional support: RVO:61388963 Keywords : rare earth ions * photophysical properties * europium(III) complexes Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 6.320, year: 2016

  12. Rare earth(III) complexes for the development of new magnetic and luminescent probes; Complexes de lanthanides(III) pour le developpement de nouvelles sondes magnetiques et luminescentes

    Energy Technology Data Exchange (ETDEWEB)

    Nonat, A

    2007-10-15

    The simultaneous optimisation of the molecular parameters determining the relaxivity (number of coordinated water molecules, water-exchange, rotation dynamics of the whole complex, electronic relaxation, Gd(III)-proton distance) is essential to prepare efficient contrast agents. The aim of this work is on the one hand to design and study complexes with a high number of bound water molecules and to understand the influence of the coordination sphere on the stability and on the electronic relaxation and on the other hand, to use the ligand as a chromophore for the development of luminescent probes for biomedical imaging. We present the structure, the stability and the relaxivity of Gd(III) complexes of two series of tripodal ligands containing picolinate units based either on the 1,4,7-tri-aza-cyclononane ring or on a tertiary amine. These complexes show high relaxivity in water and in serum and can establish a non covalent interaction with serum albumin. The interpretation of the water proton relaxivity with the help of new relaxometric methods based on an auxiliary probe solute has allowed us to show that both the presence of the picolinate groups and the 1,4,7-tri-aza-cyclononane framework can lead to Gd(III) complexes with favourable electronic relaxation properties. This ligands have also been used for Eu(III) and Tb(III) complexation leading to strong luminescence in visible light. Other complexes derived from 8-hydroxyquinoline unit which display a very high luminescence in infrared are also studied. (author)

  13. Photocytotoxicity and DNA photocleavage activity of La(III) and Gd(III) complexes of phenanthroline bases

    International Nuclear Information System (INIS)

    Hussain, Akhtar; Saha, Sounik; Chakravarty, Akhil R.; Majumdar, Ritankar; Dighe, Rajan R.

    2011-01-01

    Lanthanide(III) complexes (La(B)(acac) 3 ) (1-3) and (Gd(B)(acac) 3 ) (4-6), where B is a N,N-donor phenanthroline base, viz., 1,10-phenanthroline (phen in 1, 4), dipyrido(3,2-d:2',3'-f)quinoxaline (dpq in 2, 5) and dipyrido(3,2-a:2',3'-c)phena-zine (dppz in 3, 6), have been prepared and characterized. The Gd(III) complexes 4 - 6 are structurally characterized by single crystal X-ray crystallography. The complexes display GdO 6 N 2 coordination with the ligands showing bidentate chelating mode of bonding. The complexes are non-electrolytic in aqueous DMF and exhibit ligand-centered absorption bands in the UV region. The dppz complexes show a band at 380 nm in DMF. The La(III) complexes are diamagnetic. The Gd(III) complexes are paramagnetic with magnetic moment that corresponds to seven unpaired electrons. The complexes are avid binders to calf thymus DNA giving K b values in the range of 4.7 x 10 4 - 6.1 x 10 5 M -1 with a relative binding order: 3, 6 (dppz) > 2, 5 (dpq) > 1, 4 (phen). The binding data suggest DNA surface and/or groove binding nature of the complexes. The dpq and dppz complexes efficiently cleave SC DNA to its nicked circular form in UV-A light of 365 nm via formation of both singlet oxygen ( 1 O 2 ) and hydroxyl radical (HO · ) species. The dppz complexes 3 and 6 exhibit significant PDT effect in HeLa cervical cancer cells giving respective IC 50 value of 460(±50) and 530(±30) nM in UV-A light of 365 nm, and are essentially non-toxic in dark with an IC 50 value of >100 μM. The dppz ligand alone is cytotoxic in dark and UV-A light. A significant decrease in the dark toxicity of the dppz base is observed on binding to the Ln(Ill) ion while retaining its photocytotoxicity. (author)

  14. Synthesis and DNA interaction of a Sm(III) complex of a Schiff base ...

    African Journals Online (AJOL)

    The interaction between the Sm(III) complex of an ionic Schiff base [HL]-, derived from vanillin and L-tryptophan, and herring sperm DNA at physiological pH (7.40) has been studied by UV-Vis absorption, fluorescence and viscosity methods. The binding ratios nSm(III) : nK[HL] = 1:1 and nSm(III)L: nDNA =5:1 were confirmed ...

  15. Effect of the ion force on the stability constants of the complexes LnCl2+ and LnCl2+ of Europium and Lutetium

    International Nuclear Information System (INIS)

    Fernandez R, E.; Jimenez R, M.; Solache R, M.

    2004-01-01

    A study is presented on the determination of the constants of stability of those complex LnCI 3-n n (where Ln = Eu 3+ and Lu 3+ and n = 1 and 2), by means of a method of extraction with solvent, to constant temperature (303 K) and in means of high ionic force (1- 3M H CI/HCIO 4 ). It is also presented the application of the theory of the specific interaction of ions (SIT) of Bronsted-Guggenheim-Scatchard for the extrapolation of the values to infinite dilution. (Author)

  16. Preparation and chemical studies on Tc(III) complexes containing polyaminocarboxylic acids

    International Nuclear Information System (INIS)

    Gonzalez, R.; Kremer, C.; Chiozzone, R.; Torres, J.; Rivero, M.; Kremer, E.; Leon, A.

    1998-01-01

    Tc(III)-edta (edta = ethylenediaminetetraacetate), Tc(III)-dtpa (dtpa = diethylenetriaminepentaacetate) and Tc(III)-mebrofenin (mebrofenin = 3-bromo-2,4,6-trimethylacetanilideiminodiacetate) complexes were prepared by ligand substitution reactions on hexakis(thiourea)technetium(III) cation with the polycarboxylates. By a combination of different techniques (UV-Vis, IR and 1 H-NMR spectroscopy, Tc elemental analyses and cerimetric titrations) it was concluded that 1:1 complexes are formed with edta and dtpa while mebrofening adopts a 2:1 (ligand to metal) stoichiometry. Complementary, molecular mechanics calculations were performed to analyze the spatial arrangement of the molecules. The stability of the Tc(III) complexes was studied in aqueous solution by paper chromatography, paper electrophoresis and cyclic voltammetry. The chelates are rather stable, in particular when compared with the precursor. (orig.)

  17. Synthesis and spectral studies of some lanthanide(III) complexes ...

    African Journals Online (AJOL)

    ... compounds were characterized through various physico-chemical studies. The coordinating ligand DABAAPS behave as tridentate N,N,O-donors. The central metal ion displays the coordination number nine in these complexes. Thermal stabilities of these complexes were also studied through thermogravimetric analysis.

  18. Triheterometallic Lanthanide Complexes Prepared from Kinetically Inert Lanthanide Building Blocks

    DEFF Research Database (Denmark)

    Sørensen, Thomas Just; Tropiano, Manuel; Kenwright, Alan M.

    2017-01-01

    Three molecular structures, each containing three different lanthanide(III) centres, have been prepared by coupling three kinetically inert lanthanide(III) complexes in an Ugi reaction. These 2 kDa molecules were purified by dialysis and characterised by NMR and luminescence techniques. The photo...... and lanthanide(III) centres in these molecules inhibits the efficient sensitisation of europium. We conclude that the intramolecular collisions required for efficient Dexter energy transfer from the sensitiser to the lanthanide(III) centre can be prevented by steric congestion....

  19. Intrathecal synthesis of antibodies to HTLV-III in patients without AIDS or AIDS related complex

    NARCIS (Netherlands)

    Goudsmit, J.; Wolters, E. C.; Bakker, M.; Smit, L.; van der Noordaa, J.; Hische, E. A.; Tutuarima, J. A.; van der Helm, H. J.

    1986-01-01

    De novo synthesis in the central nervous system of IgG antibodies to human T cell lymphotropic virus type III (HTLV-III) (lymphadenopathy associated virus) was shown in seven of 10 seropositive men who had syphilis but not the acquired immune deficiency syndrome (AIDS) or AIDS related complex. None

  20. Complexation Effect on Redox Potential of Iron(III)-Iron(II) Couple: A Simple Potentiometric Experiment

    Science.gov (United States)

    Rizvi, Masood Ahmad; Syed, Raashid Maqsood; Khan, Badruddin

    2011-01-01

    A titration curve with multiple inflection points results when a mixture of two or more reducing agents with sufficiently different reduction potentials are titrated. In this experiment iron(II) complexes are combined into a mixture of reducing agents and are oxidized to the corresponding iron(III) complexes. As all of the complexes involve the…

  1. The study of Cr(III) complexation in the xylem sap using ion exchange and radiotracer

    International Nuclear Information System (INIS)

    Juneja, Shikha; Prakash, Satya

    2003-01-01

    Radiotracer was employed to carry out ion exchange experiments to study the chromium speciation in the in vitro samples of xylem sap of maize stem of 60 days old plants. Cr(III) radiolabelled with its radioactive isotope ( 51 Cr) was mixed with both the ion exchange fraction of the sap which represented the carboxylic acids, as well as the whole sap and was analysed for complexation after 10 and 30 days at 25 degC. Prior to this, the ion exchange elution chromatography of Cr(III), and the Cr(III) complexes with oxalic and citric acid were used to compare the complexes being formed in the in vitro studies. The in vitro Cr(III) complexation results indicated that Cr(III) was vitally present as anionic species. The elution curve trend was similar to that of citric acid complexation. Citric acid was also found to be the major complexing acid in the xylem sap as determined by HPLC. The results indicate the transportation of Cr(III) as a citrate complex in the xylem sap of maize plants. (author)

  2. Development of a C3-symmetric benzohydroxamate tripod: Trimetallic complexation with Fe(III), Cr(III) and Al(III)

    Science.gov (United States)

    Baral, Minati; Gupta, Amit; Kanungo, B. K.

    2016-06-01

    The design, synthesis and physicochemical characterization of a C3-symmetry Benzene-1,3,5-tricarbonylhydroxamate tripod, noted here as BTHA, are described. The chelator was built from a benzene as an anchor, symmetrically extended by three hydroxamate as ligating moieties, each bearing O, O donor sites. A combination of absorption spectrophotometry, potentiometry and theoretical investigations are used to explore the complexation behavior of the ligand with some trivalent metal ions: Fe(III), Cr(III), and Al(III). Three protonation constants were calculated for the ligand in a pH range of 2-11 in a highly aqueous medium (9:1 H2O: DMSO). A high rigidity in the molecular structure restricts the formation of 1:1 (M/L) metal encapsulation but shows a high binding efficiency for a 3:1 metal ligand stoichiometry giving formation constant (in β unit) 28.73, 26.13 and 19.69 for [M3L]; Mdbnd Fe(III), Al(III) and Cr(III) respectively, and may be considered as an efficient Fe-carrier. The spectrophotometric study reveals of interesting electronic transitions occurred during the complexation. BTHA exhibits a peak at 238 nm in acidic pH and with the increase of pH, a new peak appeared at 270 nm. A substantial shifting in both of the peaks in presence of the metal ions implicates a s coordination between ligand and metal ions. Moreover, complexation of BTHA with iron shows three distinct colors, violet, reddish orange and yellow in different pH, enables the ligand to be considered for the use as colorimetric sensor.

  3. A highly luminescent dinuclear Eu(III) complex based on 4,4'-bis (4'',4'',4''-trifluoro-1'',3''-dioxobutyl)-o-terphenyl for light-emitting diodes

    International Nuclear Information System (INIS)

    Liu Shenggui; He Pei; Wang Huihui; Shi Jianxin; Gong Menglian

    2009-01-01

    A dinuclear Eu(III) complex Eu 2 (btbt) 3 .4H 2 O.CH 3 CH 2 OH.N(CH 2 CH 3 ) 3 was synthesized, where H 2 (btbt) was 4,4'-bis (4'',4'',4'',-trifluoro-1'',3''-dioxobutyl)-o-terphenyl. The composition and structure of the complex were characterized by elemental analysis, IR, UV-vis and FAB-MS spectroscopy. The complex emits the characteristic red luminescence of Eu 3+ ion due to the 5 D 0 → 7 F J (J = 0-4) transitions under ∼395 nm-light excitation with good luminescent quantum efficiency (32%) and exhibits high thermal stability (337 deg. C). Bright red light-emitting diodes (LEDs) were fabricated by coating the complex onto a ∼395 nm-emitting InGaN chip. When the mass ratio of the red phosphor to the silicone is 1:30, the efficiency of the fabricated LEDs with the europium complex is 0.98 lm w -1 . The CIE chromaticity coordinates of the LEDs are x = 0.6057 and y = 0.3137, which are close to the National Television Standard Committee (NTSC) standard values for red color. The results indicate that the complex may act as a red component in the fabrication of near UV InGaN-based white light-emitting diodes with high color-rendering index.

  4. Synthesis of ruthenium (III) complexes with benzimidazole derivatives

    International Nuclear Information System (INIS)

    Vyas, P.C.; Chahar, Yogesh K.; Garg, Yajula; Seth, Gita

    2003-01-01

    Complexes of ruthenium with biologically important benzimidazole derivatives, viz. 2-(2'-hydroxyphenyl) benzimidazole (HOPBI), 2-2'- mercaptophenyl) benzimidazole (HSPBI), 2- (2'-hydroxynaphthyl) benzimidazole (HONBI) have been synthesized and characterized. (author)

  5. 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.

  6. Synthesis and characterization of Fe(III-piperazine-derived complexes encapsulated in zeolite Y

    Directory of Open Access Journals (Sweden)

    Márcio E. Berezuk

    2012-01-01

    Full Text Available Zeolite-encapsulated complexes have been widely applied in hydrocarbon oxidation catalysis. The "ship-in-a-bottle" encapsulation of iron(III complexes containing piperazine and piperazine-derivative ligands in zeolite-Y is described. The flexible ligand methodology was employed and the efficiency and reproducibility of the procedure was investigated. The catalysts were characterized employing several techniques and the results indicate the presence of coordinated and uncoordinated iron(III ions inside and outside the zeolitic cage.

  7. Enantiomeric separation of iridium (III) complexes using HPLC chiral stationary phases based on amylose derivatives

    International Nuclear Information System (INIS)

    Kim, Hee Eun; Seo, Na Hyeon; Hyun, Myung Ho

    2016-01-01

    Cyclometalated iridium (III) complexes formed with three identical cyclometalating (C-N) ligands (homoleptic) or formed with two cyclometalating (C-N) ligands and one ancillary (LX) ligand (heteroleptic) have been known as highly phosphorescent materials and, thus, they have been utilized as efficient phosphorescent dopants in organic light emitting diodes (OLEDs) 1–3 or as effective phosphorescent chemosensors. 4–7 Cylometalated iridium (III) complexes are chiral compounds consisting of lambda (Λ, left-handed) and delta (Δ, right-handed) isomers. Racemic cyclometa- lated iridium (III) complexes emit light with no net polarization, but optically active cyclometalated iridium (III) complexes emit circularly polarized light. 8,9 Circularly polarized light can be used in various fields including highly efficient three dimensional electronic devices, photo nic devices for optical data storage, biological assays, and others. 8,9 In order to obtain optically active cylometalated iridium (III) complexes and to determine the enantiomeric composition of optically active cylometalated iridium (III) complexes, liquid chromatogr aphic enantiomer separation method on chiral stationary phases (CSPs) has been used. For example, Okamoto and coworkers first reported the high performance liquid chromatographic (HPLC) direct enantiomeric separation of two homoleptic cylometalated iridium (III) complexes on immobilized amylose tris(3,5- dimethylphenylcarbamate) (Chiralpak IA), coated cellulose tris(3,5-dimethylphenylcarbamate) (Chiralc el OD), and coated cellulose tris(4-methylbenzoate) (Chiralce l OJ). 10 Supercritical fluid chromatography (SFC) was also used by Bernhard and coworkers for the enantiomeric separation of cylometalated iridium (III) complexes on coated amylose tris(3,5-dimethylphenylcarbamate) (Chiralpak AD-H). 8 However, the general use of the HPLC method for the direct enantiomeric separation of homoleptic

  8. Enantiomeric separation of iridium (III) complexes using HPLC chiral stationary phases based on amylose derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hee Eun; Seo, Na Hyeon; Hyun, Myung Ho [Dept. of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan (Korea, Republic of)

    2016-12-15

    Cyclometalated iridium (III) complexes formed with three identical cyclometalating (C-N) ligands (homoleptic) or formed with two cyclometalating (C-N) ligands and one ancillary (LX) ligand (heteroleptic) have been known as highly phosphorescent materials and, thus, they have been utilized as efficient phosphorescent dopants in organic light emitting diodes (OLEDs) 1–3 or as effective phosphorescent chemosensors. 4–7 Cylometalated iridium (III) complexes are chiral compounds consisting of lambda (Λ, left-handed) and delta (Δ, right-handed) isomers. Racemic cyclometa- lated iridium (III) complexes emit light with no net polarization, but optically active cyclometalated iridium (III) complexes emit circularly polarized light. 8,9 Circularly polarized light can be used in various fields including highly efficient three dimensional electronic devices, photo nic devices for optical data storage, biological assays, and others. 8,9 In order to obtain optically active cylometalated iridium (III) complexes and to determine the enantiomeric composition of optically active cylometalated iridium (III) complexes, liquid chromatogr aphic enantiomer separation method on chiral stationary phases (CSPs) has been used. For example, Okamoto and coworkers first reported the high performance liquid chromatographic (HPLC) direct enantiomeric separation of two homoleptic cylometalated iridium (III) complexes on immobilized amylose tris(3,5- dimethylphenylcarbamate) (Chiralpak IA), coated cellulose tris(3,5-dimethylphenylcarbamate) (Chiralc el OD), and coated cellulose tris(4-methylbenzoate) (Chiralce l OJ). 10 Supercritical fluid chromatography (SFC) was also used by Bernhard and coworkers for the enantiomeric separation of cylometalated iridium (III) complexes on coated amylose tris(3,5-dimethylphenylcarbamate) (Chiralpak AD-H). 8 However, the general use of the HPLC method for the direct enantiomeric separation of homoleptic.

  9. Rhombus-shaped tetranuclear [Ln4] complexes [Ln = Dy(III) and Ho(III)]: synthesis, structure, and SMM behavior.

    Science.gov (United States)

    Chandrasekhar, Vadapalli; Hossain, Sakiat; Das, Sourav; Biswas, Sourav; Sutter, Jean-Pascal

    2013-06-03

    The reaction of a new hexadentate Schiff base hydrazide ligand (LH3) with rare earth(III) chloride salts in the presence of triethylamine as the base afforded two planar tetranuclear neutral complexes: [{(LH)2Dy4}(μ2-O)4](H2O)8·2CH3OH·8H2O (1) and [{(LH)2Ho4}(μ2-O)4](H2O)8·6CH3OH·4H2O (2). These neutral complexes possess a structure in which all of the lanthanide ions and the donor atoms of the ligand remain in a perfect plane. Each doubly deprotonated ligand holds two Ln(III) ions in its two distinct chelating coordination pockets to form [LH(Ln)2](4+) units. Two such units are connected by four [μ2-O](2-) ligands to form a planar tetranuclear assembly with an Ln(III)4 core that possesses a rhombus-shaped structure. Detailed static and dynamic magnetic analysis of 1 and 2 revealed single-molecule magnet (SMM) behavior for complex 1. A peculiar feature of the χM" versus temperature curve is that two peaks that are frequency-dependent are revealed, indicating the occurrence of two relaxation processes that lead to two energy barriers (16.8 and 54.2 K) and time constants (τ0 = 1.4 × 10(-6) s, τ0 = 7.2 × 10(-7) s). This was related to the presence of two distinct geometrical sites for Dy(III) in complex 1.

  10. In vivo toxicity studies of europium hydroxide nanorods in mice

    International Nuclear Information System (INIS)

    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 and pro-angiogenic properties to endothelial cells, respectively. Recently, we have demonstrated that europium (III) hydroxide [Eu III (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 mg kg -1 day -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 euthanized on days 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.

  11. Spectroscopic investigation of complexation of Cm(III) und Eu(III) with partitioning-relevant N-donor ligands

    International Nuclear Information System (INIS)

    Bremer, Antje

    2014-01-01

    The separation of trivalent actinides and lanthanides is an essential part of the development of improved nuclear fuel cycles. Liquid-liquid extraction is an applicable technique to achieve this separation. Due to the chemical similarity and the almost identical ionic radii of trivalent actinides and lanthanides this separation is, however, only feasible with highly selective extracting agents. It has been proven that molecules with soft sulphur or nitrogen donor atoms have a higher affinity for trivalent actinides. In the present work, the complexation of Cm(III) and Eu(III) with N-donor ligands relevant for partitioning has been studied by time-resolved laser fluorescence spectroscopy (TRLFS). This work aims at a better understanding of the molecular reason of the selectivity of these ligands. In this context, enormous effort has been and is still put into detailed investigations on BTP and BTBP ligands, which are the most successful N-donor ligands for the selective extraction of trivalent actinides, to date. Additionally, the complexation and extraction behavior of molecules which are structurally related to these ligands is studied. The ligand C5-BPP (2,6-bis(5-(2,2-dimethylpropyl)-1H-pyrazol-3-yl)pyridine) where the triazine rings of the aromatic backbone of the BTP ligands have been replaced by pyrazole rings is one of these molecules. Laser fluorescence spectroscopic investigation of the complexation of Cm(III) with this ligand revealed stepwise formation of three (Cm(C5-BPP) n ) 3+ complexes (n = 1 - 3). The stability constant of the 1:3 complex was determined (log β 3 = 14.8 ± 0.4). Extraction experiments have shown that, in contrast to BTP and BTBP ligands, C5-BPP needs an additional lipophilic anion source such as a 2-bromocarboxylic acid to selectively extract trivalent actinides from nitric acid solutions. The comparison of the stability constant of the (Cm(C5-BPP) 3 ) 3+ complex with the stability constant of the (Cm(nPr-BTP) 3 ) 3+ complex

  12. 21 CFR 176.160 - Chromium (Cr III) complex of N-ethyl-N-heptadecylfluoro-octane sulfonyl glycine.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Chromium (Cr III) complex of N-ethyl-N... § 176.160 Chromium (Cr III) complex of N-ethyl-N-heptadecylfluoro-octane sulfonyl glycine. The chromium... by weight of the chromium (Cr III) complex of heptadecylfluoro-octane sulfonic acid may be safely...

  13. Spectrophotometric determination of ruthenium(III) and rhodium(III) after extraction of their cyclohexylthioglycolate complexes into chloroform

    International Nuclear Information System (INIS)

    Rao, A.L.J.; Gupta, Usha; Puri, B.K.

    1986-01-01

    Cyclohexylthioglycolate has been used as a reagent for the spectrophotometric determination of ruthenium(III) and rhodium(III) after the extraction of their complexes into chloroform. Various parameters involved in the extraction have been studied and the composition of the extracted complex has been established in each instance. Ruthenium and rhodium complexes are extracted into chloroform in the pH ranges 5.0-9.0 and 9.0-12.5, respectively. The ruthenium complex absorbs strongly at 365 nm, whereas the rhodium complex shows a maximum absorption at 345 nm. Beer's law is obeyed over the concentration range 6-96 μg for ruthenium and 2-41 μg for rhodium in 10 ml of the chloroform solution. The molar absorptivities are 5.02 x 10 3 l mol -1 cm -1 for ruthenium and 1.60 x 10 4 l mol -1 cm -1 for rhodium. Ten replicate determinations on a sample solution containing 60.3 μg of ruthenium or 20.6 μg of rhodium gave mean absorbances of 0.300 and 0.320 with standard deviations of 0.0021 and 0.0025 and relative standard deviations of 0.70% and 0.78%, respectively. The interference of various ions has been studied and the method has been applied to the determination of the metals in various synthetic samples. Conditions have also been developed for the simultaneous determination of ruthenium and rhodium. (author)

  14. Cr(III), Fe(III) and Co(III) complexes of tetradentate (ONNO) Schiff base ligands: Synthesis, characterization, properties and biological activity

    Science.gov (United States)

    Keskioğlu, Eren; Gündüzalp, Ayla Balaban; Çete, Servet; Hamurcu, Fatma; Erk, Birgül

    2008-08-01

    A series of metal complexes were synthesized from equimolar amounts of Schiff bases: 1,4-bis[3-(2-hydroxy-1-naphthaldimine)propyl]piperazine (bappnaf) and 1,8-bis[3-(2-hydroxy-1-naphthaldimine)- p-menthane (damnaf) with metal chlorides. All of synthesized compounds were characterized by elemental analyses, spectral (UV-vis, IR, 1H- 13C NMR, LC-MS) and thermal (TGA-DTA) methods, magnetic and conductance measurements. Schiff base complexes supposed in tetragonal geometry have the general formula [M(bappnaf or damnaf)]Cl· nH 2O, where M = Cr(III), Co(III) and n = 2, 3. But also Fe(III) complexes have octahedral geometry by the coordination of two water molecules and the formula is [Fe(bappnaf or damnaf)(H 2O) 2]Cl. The changes in the selected vibration bands in FT-IR indicate that Schiff bases behave as (ONNO) tetradentate ligands and coordinate to metal ions from two phenolic oxygen atoms and two azomethine nitrogen atoms. Conductance measurements suggest 1:1 electrolytic nature of the metal complexes. The synthesized compounds except bappnaf ligand have the antimicrobial activity against the bacteria: Escherichia coli (ATCC 11230), Yersinia enterocolitica (ATCC 1501), Bacillus magaterium (RSKK 5117), Bacillus subtilis (RSKK 244), Bacillus cereus (RSKK 863) and the fungi: Candida albicans (ATCC 10239). These results have been considerably interest in piperazine derivatives due to their significant applications in antimicrobial studies.

  15. Novel Luminescent Probe Based on a Terbium(III) Complex for Hemoglobin Determination

    Science.gov (United States)

    Yegorova, A. V.; Leonenko, I. I.; Aleksandrova, D. I.; Scrypynets, Yu. V.; Antonovich, V. P.; Ukrainets, I. V.

    2014-09-01

    We have studied the spectral luminescent properties of Tb(III) and Eu(III) complexes with a number of novel derivatives of oxoquinoline-3-carboxylic acid amides (L1-L5 ). We have observed quenching of the luminescence of 1:1 Tb(III)-L1-5 complexes by hemoglobin (Hb), which is explained by resonance energy transfer of electronic excitation from the donor (Tb(III)-L1-5 ) to the acceptor (Hb). Using the novel luminescent probe Tb(III)-L1, we have developed a method for determining Hb in human blood. The calibration Stern-Volmer plot is linear in the Hb concentration range 0.6-36.0 μg/mL, detection limit 0.2 μg/mL (3·10-9 mol/L).

  16. Complexes of technetium(IV) and (III) with tertiary phosphines

    Energy Technology Data Exchange (ETDEWEB)

    Mazzi, U; De Paoli, G; Di Bernardo, P; Magon, L [Consiglio Nazionale delle Ricerche, Padua (Italy). Lab. di Chimica e Tecnologia dei Radioelementi

    1976-01-01

    The synthesis and characterization of the complexes trans-TcX/sub 4/L/sub 2/ and mer-TcX/sub 3/L/sub 3/(X = Cl and Br, and L = PMe/sub 2/Ph, PEt/sub 2/Ph and PPh/sub 3/) are reported. Configurations were deduced by far-IR and /sup 1/H NMR studies. Magnetic susceptibility and /sup 1/H NMR results for mer-TcCl/sub 3/(PMe/sub 2/Ph)/sub 3/ are compared with those for analogues d/sup 4/ complexes.

  17. Effects of reactive Mn(III)-oxalate complexes on structurally intact plant cell walls

    Science.gov (United States)

    Summering, J. A.; Keiluweit, M.; Goni, M. A.; Nico, P. S.; Kleber, M.

    2011-12-01

    Lignin components in the in plant litter are commonly assumed to have longer residence times in soil than many other compounds, which are supposedly, more easily degradable. The supposed resistance of lignin compounds to decomposition is generally attributed to the complex chain of biochemical steps required to create footholds in the non-porous structure of ligno-cellulose in cell walls. Interestingly, Mn(III) complexes have shown the ability to degrade ligno-cellulose. Mn(III) chelated by ligands such as oxalate are soluble oxidizers with a high affinity for lignin structures. Here we determined (i) the formation and decay kinetics of the Mn(III)-oxalate complexes in aqueous solution and (ii) the effects that these complexes have on intact ligno-cellulose. UV/vis spectroscopy and iodometric titrations confirmed the transient nature of Mn(III)-oxalate complexes with decay rates being in the order of hours. Zinnia elegans tracheary elements - a model ligno-cellulose substrate - were treated with Mn(III)-oxalate complexes in a newly developed flow-through reactor. Soluble decomposition products released during the treatment were analyzed by GC/MS and the degree of cell integrity was measured by cell counts, pre- and post-treatment counts indicate a decrease in intact Zinnia elegans as a result of Mn(III)-treatment. GC/MS results showed the release of a multitude of solubilized lignin breakdown products from plant cell walls. We conclude that Mn(III)-oxalate complexes have the ability to lyse intact plant cells and solubilize lignin. Lignin decomposition may thus be seen as resource dependent, with Mn(III) a powerful resource that should be abundant in terrestrial characterized by frequent redox fluctuations.

  18. Genomic binding profiles of functionally distinct RNA polymerase III transcription complexes in human cells.

    Science.gov (United States)

    Moqtaderi, Zarmik; Wang, Jie; Raha, Debasish; White, Robert J; Snyder, Michael; Weng, Zhiping; Struhl, Kevin

    2010-05-01

    Genome-wide occupancy profiles of five components of the RNA polymerase III (Pol III) machinery in human cells identified the expected tRNA and noncoding RNA targets and revealed many additional Pol III-associated loci, mostly near short interspersed elements (SINEs). Several genes are targets of an alternative transcription factor IIIB (TFIIIB) containing Brf2 instead of Brf1 and have extremely low levels of TFIIIC. Strikingly, expressed Pol III genes, unlike nonexpressed Pol III genes, are situated in regions with a pattern of histone modifications associated with functional Pol II promoters. TFIIIC alone associates with numerous ETC loci, via the B box or a novel motif. ETCs are often near CTCF binding sites, suggesting a potential role in chromosome organization. Our results suggest that human Pol III complexes associate preferentially with regions near functional Pol II promoters and that TFIIIC-mediated recruitment of TFIIIB is regulated in a locus-specific manner.

  19. Characterization of Hydrogen Complex Formation in III-V Semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Michael D

    2006-09-28

    Atomic hydrogen has been found to react with some impurity species in semiconductors. Hydrogenation is a methodology for the introduction of atomic hydrogen into the semiconductor for the express purpose of forming complexes within the material. Efforts to develop hydrogenation as an isolation technique for AlGaAs and Si based devices failed to demonstrate its commercial viability. This was due in large measure to the low activation energies of the formed complexes. Recent studies of dopant passivation in long wavelength (0.98 - 1.55m) materials suggested that for the appropriate choice of dopants much higher activation energies can be obtained. This effort studied the formation of these complexes in InP, This material is extensively used in optoelectronics, i.e., lasers, modulators and detectors. The experimental techniques were general to the extent that the results can be applied to other areas such as sensor technology, photovoltaics and to other material systems. The activation energies for the complexes have been determined and are reported in the scientific literature. The hydrogenation process has been shown by us to have a profound effect on the electronic structure of the materials and was thoroughly investigated. The information obtained will be useful in assessing the long term reliability of device structures fabricated using this phenomenon and in determining new device functionalities.

  20. Characterization of Aluminum(III) Complexes in Coal Organic Matter

    Czech Academy of Sciences Publication Activity Database

    Straka, Pavel

    2016-01-01

    Roč. 7, č. 4 (2016), s. 378-394 ISSN 2156-8251 Institutional support: RVO:67985891 Keywords : aluminium * complex * 27Al MAS NMR * coal * lignite * altered coal Subject RIV: DD - Geochemistry http://www.scirp.org/journal/AJAC/

  1. Lanthanide(III) Complexes with Tridentate Schiff Base Ligand ...

    African Journals Online (AJOL)

    Lanthanide complexes, hydrazino, antioxidant activity, X-ray structure. 1. Introduction ... measured using a Johnson Matthey scientific magnetic suscepti- bility balance. 2.1. .... of the ligand and that the nitrogen atom supporting this proton is not involved in the ... 4f-electrons are not involved in the coordination. These facts.

  2. Evaluation of beta-decay III. The complex gamma function

    International Nuclear Information System (INIS)

    Wilkinson, D.H.

    1993-05-01

    Two real, analytical, approximations for the square of the modulus of the complex gamma function as it appears in F(Z, W), the Fermi function for beta-decay, are evaluated; an accuracy bettering 10 -4 % can easily be achieved for all electron energies throughout the periodic table. (author). 3 refs., 1 tab., 7 figs

  3. and cobalt(III) octahedral monomer complexes: Synthesis and ...

    Indian Academy of Sciences (India)

    In compound 2 the central cobalt is in +3 oxidation state while `in' compound 2, the nickel ion is in +2 oxidation state. The two complexes are isostructural with octahedral coordination environment exhibiting helical twist topology. They also display strong H-bonding as well as CH- interactions to generate 1D chain.

  4. Plane Transformations in a Complex Setting III: Similarities

    Science.gov (United States)

    Dana-Picard, Thierry

    2009-01-01

    This is the third part of a study of plane transformations described in a complex setting. After the study of homotheties, translations, rotations and reflections, we proceed now to the study of plane similarities, either direct or inverse. Their group theoretical properties are described, and their action on classical geometrical objects is…

  5. Complex Formation Between Iron(III) and Isonicotinohydroxamic ...

    African Journals Online (AJOL)

    acer

    as a consequence of their biological importance which is related ... complexes with a series of metal ions via co- ordination ... water was added with stirring to a solution of ... Evaluation of the antimicrobial activity ... All are regarded as pathogenic to ... each agar dish and fresh bacteria suspension was .... Copper(II) Mixed.

  6. Iron(III) complexes of certain tetradentate phenolate ligands as ...

    Indian Academy of Sciences (India)

    non-heme iron enzymes, which catalyse the oxidative cleavage of catechols to cis, cis-muconic acids with the incorporation of ... nature of heterocyclic rings of the ligands and the methyl substituents on them regulate the electronic spectral features .... and simple substitution reactions.19,21 The complexes of [H2(L5)] and ...

  7. Incremental binding free energies of aluminum (III) vs. magnesium (II) complexes

    International Nuclear Information System (INIS)

    Mercero, Jose M.; Mujika, Jon I.; Matxain, Jon M.; Lopez, Xabier; Ugalde, Jesus M.

    2003-01-01

    A sequential ligand addition to the aluminum (III) cation has been studied using the B3LYP functional and a combined all-electron/pseudopotentials basis set. The aluminum complexes are compared with analogous magnesium (II) complexes. Different thermodynamical data, such as incremental binding energies, enthalpies, entropies and free energies, are presented for these addition reactions. While the magnesium (II) cation can only accommodate three negatively charged ligands, aluminum (III) accommodates four even after including bulk solvent effects. The main differences between both cations complexing with the neutral ligands, is that aluminum (III) is not able to form complexes with methanol until the number of methanol ligands is equal to 3. Magnesium (II) prefers to bind methanol and formamide when the number of ligands is small, while aluminum prefers formamide. For the largest complexes both cations prefer to bind water

  8. Thermal decomposition of lanthanides (III) and yttrium (III) solid complexes from ethyl ene diamine tetraacetic acid

    International Nuclear Information System (INIS)

    Mercadante, A.

    1991-01-01

    Solid state compounds of lanthanides (III) and yttrium derived from ethyl ene diamine tetraacetic acid were prepared from respective basic carbonates, that were neutralized with EDTA stoichiometry quantities. Complexometry with EDTA, thermogravimetry (TG), differential thermal analysis (DTA) and X-ray diffraction have been used in the study of these compounds. The results of complexometry with EDTA as well as TG and DTA curves bed to the stoichiometry of these compounds the following general formula is obeyed: H[Ln(EDTA]. n H 2 O. X-ray powder patterns of these compounds permitted to establish two isomorphous series. The DTA ant TG curves allowed us to study the dehydration process, the thermal stability and thermal decomposition of these compounds. (C.G.C.)

  9. Complexes of Sm(III) and Dy(III) with piperazines

    Energy Technology Data Exchange (ETDEWEB)

    Manhas, B S; Trikha, A K [Punjabi Univ., Patiala (India). Dept. of Chemistry; Singh, M [Guru Nanak Dev Univ., Amritsar (India). Dept. of Chemistry

    1981-09-01

    Complexes of SmCl/sub 3/, DyCl/sub 3/, Sm(NO/sub 3/)/sub 3/ and Dy(NO/sub 3/) with piperazine, N-methylpiperazine, 2-methylpiperazine, N-phenyl-piperazine and N, N'-dimethyl-piperazine have been prepared and characterized on the basis of elemental analyses, IR and electronic reflectance spectra and magnetic susceptibility measurements. IR data indicate that the ligands are coordinated in the chair conformation giving polymeric bridged complexes and that the nitrate group is bidentate. Coordination numbers from 6 to 12 are proposed for the lanthanide ions.

  10. Organometallic rhodium(III) and iridium(III) cyclopentadienyl complexes with curcumin and bisdemethoxycurcumin co-ligands.

    Science.gov (United States)

    Pettinari, Riccardo; Marchetti, Fabio; Pettinari, Claudio; Condello, Francesca; Petrini, Agnese; Scopelliti, Rosario; Riedel, Tina; Dyson, Paul J

    2015-12-21

    A series of half-sandwich cyclopentadienyl rhodium(III) and iridium(III) complexes of the type [Cp*M(curc/bdcurc)Cl] and [Cp*M(curc/bdcurc)(PTA)][SO3CF3], in which Cp* = pentamethylcyclopentadienyl, curcH = curcumin and bdcurcH = bisdemethoxycurcumin as O^O-chelating ligands, and PTA = 1,3,5-triaza-7-phosphaadamantane, is described. The X-ray crystal structures of three of the complexes, i.e. [Cp*Rh(curc)(PTA)][SO3CF3] (5), [Cp*Rh(bdcurc)(PTA)][SO3CF3] (6) and [Cp*Ir(bdcurc)(PTA)][SO3CF3] (8), confirm the expected "piano-stool" geometry. With the exception of 5, the complexes are stable under pseudo-physiological conditions and are moderately cytotoxic to human ovarian carcinoma (A2780 and A2780cisR) cells and also to non-tumorigenic human embryonic kidney (HEK293) cells, but lack the cancer cell selectivity observed for related arene ruthenium(II) complexes.

  11. [Tl(III)(dota)](-): An Extraordinarily Robust Macrocyclic Complex.

    Science.gov (United States)

    Fodor, Tamás; Bányai, István; Bényei, Attila; Platas-Iglesias, Carlos; Purgel, Mihály; Horváth, Gábor L; Zékány, László; Tircsó, Gyula; Tóth, Imre

    2015-06-01

    The X-ray structure of {C(NH2)3}[Tl(dota)]·H2O shows that the Tl(3+) ion is deeply buried in the macrocyclic cavity of the dota(4-) ligand (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate) with average Tl-N and Tl-O distances of 2.464 and 2.365 Å, respectively. The metal ion is directly coordinated to the eight donor atoms of the ligand, which results in a twisted square antiprismatic (TSAP') coordination around Tl(3+). A multinuclear (1)H, (13)C, and (205)Tl NMR study combined with DFT calculations confirmed the TSAP' structure of the complex in aqueous solution, which exists as the Λ(λλλλ)/Δ(δδδδ) enantiomeric pair. (205)Tl NMR spectroscopy allowed the protonation constant associated with the protonation of the complex according to [Tl(dota)](-) + H(+) ⇆ [Tl(Hdota)] to be determined, which turned out to be pK(H)Tl(dota) = 1.4 ± 0.1. [Tl(dota)](-) does not react with Br(-), even when using an excess of the anion, but it forms a weak mixed complex with cyanide, [Tl(dota)](-) + CN(-) ⇆ [Tl(dota)(CN)](2-), with an equilibrium constant of Kmix = 6.0 ± 0.8. The dissociation of the [Tl(dota)](-) complex was determined by UV-vis spectrophotometry under acidic conditions using a large excess of Br(-), and it was found to follow proton-assisted kinetics and to take place very slowly (∼10 days), even in 1 M HClO4, with the estimated half-life of the process being in the 10(9) h range at neutral pH. The solution dynamics of [Tl(dota)](-) were investigated using (13)C NMR spectroscopy and DFT calculations. The (13)C NMR spectra recorded at low temperature (272 K) point to C4 symmetry of the complex in solution, which averages to C4v as the temperature increases. This dynamic behavior was attributed to the Λ(λλλλ) ↔ Δ(δδδδ) enantiomerization process, which involves both the inversion of the macrocyclic unit and the rotation of the pendant arms. According to our calculations, the arm-rotation process limits the Λ(λλλλ) ↔

  12. Structural characterization of Am(III) formate complexes. Combining EXAFS spectroscopy with DFT and thermodynamical calculations

    Energy Technology Data Exchange (ETDEWEB)

    Rossberg, Andre [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Molecular Structures; Froehlich, D.R. [Heidelberg Univ. (Germany). Physikalisch-Chemisches Inst.

    2017-06-01

    We used iterative transformation factor analysis (ITFA) in order to isolate the EXAFS spectral contributions of the complexing ligand from a Am(III)/formate pH-series. Thermodynamic calculations were used as constraint for ITFA and for density functional theory (DFT) calculations to identify the coordination mode within the formed complexes.

  13. Copolymers containing phosphorescent iridium(III) complexes obtained by free and controlled radical polymerization techniques

    NARCIS (Netherlands)

    Ulbricht, C.; Becer, C.R.; Winter, A.; Veldman, D.; Schubert, U.S.

    2008-01-01

    A methacrylate-functionalized phosphorescent Ir(III)-complex has been synthesized, characterized, and applied as a monomer in radical copolymerizations. Together with methyl methacrylate, the complex has been copolymerized under free radical polymerization conditions. Aiming for host-guest-systems,

  14. Interaction of complexes I, III, and IV within the bovine respirasome by single particle cryoelectron tomography

    NARCIS (Netherlands)

    Dudkina, Natalya V.; Kudryashev, Mikhail; Stahlberg, Henning; Boekema, Egbert J.

    2011-01-01

    The respirasome is a multisubunit supercomplex of the respiratory chain in mitochondria. Here we report the 3D reconstruction of the bovine heart respirasome, composed of dimeric complex III and single copies of complex I and IV, at about 2.2-nm resolution, determined by cryoelectron tomography and

  15. Interaction of Cr (III), Ni (II), Pb (II) with DTPA complexes of essential metal ions

    International Nuclear Information System (INIS)

    Gulzar, S.; Zahida; Maqsood, T.; Naqvi, R.R.

    2002-01-01

    With the increase of anthropogenic activities in the environment, heavy metal toxicity (Chromium, Nickel and Lead) is more common now. DTPA (diethylene triamine pentaacetic acid) a polyamino carboxylic acid is widely used to form hydrophilic and stable complexes with most of the metal ions. In this spectrophotometric study, concentration of Cr(III), Ni(II) and Pb(II) (toxic metal ions) exchanged with Fe(III), Zn(II) and Ca(II) from their DTPA complexes were estimated at pH 4,7 and 9. Concentration of added metal was varied from 1-4 times to that of complexed metal. (author)

  16. A general access to organogold(iii) complexes by oxidative addition of diazonium salts.

    Science.gov (United States)

    Huang, Long; Rominger, Frank; Rudolph, Matthias; Hashmi, A Stephen K

    2016-05-11

    At room temperature under mild photochemical conditions, namely irradiation with a simple blue light LED, gold(i) chloro complexes of both phosphane and carbene ligands in combination with aryldiazonium salts afford arylgold(iii) complexes. With chelating P,N-ligands cationic six- or five-membered chelate complexes were isolated in the form of salts with weakly coordinating counter anions that were brought in from the diazonium salt. With monodentate P ligands or N-heterocyclic carbene ligands and diazonium chlorides neutral arylgold(iii) dichloro complexes were obtained. The coordination geometry was determined by X-ray crystal structure analyses of representative compounds, a cis arrangement of the aryl and the phosphane ligand at the square planar gold(iii) center is observed.

  17. Thermodynamics of complex formation of natural iron(III)porphyrins with neutral ligands

    International Nuclear Information System (INIS)

    Lebedeva, Nataliya Sh.; Yakubov, Sergey P.; Vyugin, Anatoly I.; Parfenyuk, Elena V.

    2003-01-01

    Calorimetric titrations in benzene and chloroform at 298.15 K have been performed to give the complexes stability constants and the thermodynamic parameters for the complex formation of nature iron(III)porphyrins with pyridine. Stoichimetry of the complexes formed has been determined. It has been found that the thermodynamic parameters obtained depend on nature of peripheral substituents of the porphyrins. The estimation of the influence of Cl - and Ac - ions on the processes studied has been carried out. Using thermodynamic analysis method, the crystallsolvates of nature iron(III)porphyrins with benzene have been studied. Stoichiometry, thermal and energetic stability of the π-π-complexes formed have been determined. The data obtained have been used to the estimate solvent effect on the thermodynamic parameters of axial coordination of pyridine on the iron(III)porphyrins in benzene

  18. 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)

  19. Syntheses, structures, and magnetic properties of a family of heterometallic heptanuclear [Cu5Ln2] (Ln = Y(III), Lu(III), Dy(III), Ho(III), Er(III), and Yb(III)) complexes: observation of SMM behavior for the Dy(III) and Ho(III) analogues.

    Science.gov (United States)

    Chandrasekhar, Vadapalli; Dey, Atanu; Das, Sourav; Rouzières, Mathieu; Clérac, Rodolphe

    2013-03-04

    Sequential reaction of the multisite coordination ligand (LH3) with Cu(OAc)2·H2O, followed by the addition of a rare-earth(III) nitrate salt in the presence of triethylamine, afforded a series of heterometallic heptanuclear complexes containing a [Cu5Ln2] core {Ln = Y(1), Lu(2), Dy(3), Ho(4), Er(5), and Yb(6)}. Single-crystal X-ray crystallography reveals that all the complexes are dicationic species that crystallize with two nitrate anions to compensate the charge. The heptanuclear aggregates in 1-6 are centrosymmetrical complexes, with a hexagonal-like arrangement of six peripheral metal ions (two rare-earth and four copper) around a central Cu(II) situated on a crystallographic inversion center. An all-oxygen environment is found to be present around the rare-earth metal ions, which adopt a distorted square-antiprismatic geometry. Three different Cu(II) sites are present in the heptanuclear complexes: two possess a distorted octahedral coordination sphere while the remaining one displays a distorted square-pyramidal geometry. Detailed static and dynamic magnetic properties of all the complexes have been studied and revealed the single-molecule magnet behavior of the Dy(III) and Ho(III) derivatives.

  20. Complexes of molybdenum(III) with 2-(2'-pyridyl)benzimidazole

    International Nuclear Information System (INIS)

    Ghosh, S.P.; Prasad, K.M.

    1979-01-01

    Molybdenum(III) forms with 2-(2'-pyridyl) benzimidazole(LH) the trischelated complexes, [Mo(LH) 3 ]X 3 as well as the cationic-anionic complexes, [Mo(LH) 3 X 2 ] + [Mo(LH)X 4 ] - (X=Cl - ,Br - or NCS - ), depending on pH. These complexes have been synthesised and characterised from elemental analyses, i.r. and electronic spectra, magnetic moments and molar conductance. (auth.)

  1. Complex I and complex III inhibition specifically increase cytosolic hydrogen peroxide levels without inducing oxidative stress in HEK293 cells

    NARCIS (Netherlands)

    Forkink, M.; Basit, F.; Teixeira, J.; Swarts, H.G.; Koopman, W.J.H.; Willems, P.H.G.M.

    2015-01-01

    Inhibitor studies with isolated mitochondria demonstrated that complex I (CI) and III (CIII) of the electron transport chain (ETC) can act as relevant sources of mitochondrial reactive oxygen species (ROS). Here we studied ROS generation and oxidative stress induction during chronic (24h) inhibition

  2. A spectrophotometric investigation of the complex formation between lanthanum (III) and eriochrome cyanine R

    International Nuclear Information System (INIS)

    Boodts, J.F.C.; Saffioti, W.

    1979-01-01

    The complex formation between La(III) and Eriochrome Cyanine R has been investigated. Three complexes have been detected. A first one (Complex I) in the pH range of 5.3-5.5 with lambda sub(max) = 460nm. a second one (Complex II) in the pH range of 6.2-6.5 with lambda sub(max) = 490nm and a third one (complex III) in the pH range of 8.2 - 9.0 with lambda sub(max) = 545nm and a shoulder between 570-580nm. The composition and stability constants of the complexes, respectively: complex I: La(ECR) 2 and 4.9 x 10 7 , complex II: La(ECR) 2 and 7.0 x 10 7 , complex III: La.ECR and 1.0 x 10 4 . All measurements were taken at 25.0 +- 0.1 0 C and μ = 0.2 (NaClO 4 ). (Author) [pt

  3. Structural variety in solvated lanthanoid (III) halide complexes

    International Nuclear Information System (INIS)

    Deacon, G.B; Feng, T.; Scott, N.M.; Junk, P.C.; James Cook University, Townsville, QLD; Meyer, G.; Skelton, B.W.; White, A.H.

    2000-01-01

    Treatment of lanthanum metal with CH 2 Br 2 or CH 2 I 2 in tetrahydrofuran (thf) under ultrasound conditions yields the corresponding [LaX 3 (thf) 4 ] (X Br, I) complexes in good yield. Recrystallization of [LaBr 3 (thf) 4 ] from 1,2-dimethoxyethane (dme) or bis(2-methoxyethyl) ether (dig-lyme) generates [LaBr 2 (μ-Br)(dme) 2 ] 2 and [LaBr 2 (dig-lyme) 2 ][LaBr 4 (diglyme)]. Treatment of lanthanoid metals with hexachloroethane in dme yields [LnCl 3 (dme) 2 ] (Ln = La, Nd, Er or Yb) and in acetonitrile [YbCl 2 (MeCN) 5 ] 2 [YbCl 3 (MeCN)(-Cl) 2 YbCl 3 (MeCN)]. The reaction of Yb metal pieces with 1,2-dibromoethane in thf and dme gave single crystals of [YbBr 3 (thf) 3 ] and [YbBr 3 (dme) 2 ], respectively. The X-ray determined structure of [LaBr 3 (thf) 4 ] shows a seven-coordinate monomer with pentagonal-bipyramidal stereochemistry and apical bromide ligands. For [YbBr 3 (thf) 3 ], a monomeric structure with mer-octahedral stereochemistry is observed. In [LaBr 2 (μ-Br)(dme) 2 ] 2 , two eight-coordinate La centres are linked by two bridging bromides. The dme ligands have a trans relationship to each other, and cis terminal bromides are transoid to the bridging bromides with dodecahedral stereochemistry for La. By contrast, the 1: 1.5 diglyme adduct is found to be ionic [LaBr 2 (diglyme) 2 ][LaBr 4 (diglyme)], with an eight-coordinate bicapped trigonal-prismatic lanthanum cation and a seven-coordinate pentagonal-bipyramidal lanthanum anion. In the cation, the bromide ligands are cis to each other, and in the anion, two bromides are equatorial and two are axial. In [YbBr 3 (dme) 2 ], [YbCl 3 (dme) 2 ] and [ErCl 3 (dme) 2 ], a seven-coordinate pentagonal-bipyramidal arrangement exists with apical halogen ligands. Far-infrared data, and in particular the absence of absorptions attributable to I(La-Cl ter ), suggest that [LaCl 3 (dme)] is polymeric with six bridging chlorides per lanthanum. For [YbCl 2 (MeCN) 5 ] 2 [YbCl 3 (MeCN)(-Cl) 2 YbCl 3 -(MeCN)], a remarkable

  4. On the structure and spin states of Fe(III)-EDDHA complexes.

    Science.gov (United States)

    Gómez-Gallego, Mar; Fernández, Israel; Pellico, Daniel; Gutiérrez, Angel; Sierra, Miguel A; Lucena, Juan J

    2006-07-10

    DFT methods are suitable for predicting both the geometries and spin states of EDDHA-Fe(III) complexes. Thus, extensive DFT computational studies have shown that the racemic-Fe(III) EDDHA complex is more stable than the meso isomer, regardless of the spin state of the central iron atom. A comparison of the energy values obtained for the complexes under study has also shown that high-spin (S = 5/2) complexes are more stable than low-spin (S = 1/2) ones. These computational results matched the experimental results of the magnetic susceptibility values of both isomers. In both cases, their behavior has been fitted as being due to isolated high-spin Fe(III) in a distorted octahedral environment. The study of the correlation diagram also confirms the high-spin iron in complex 2b. The geometry optimization of these complexes performed with the standard 3-21G* basis set for hydrogen, carbon, oxygen, and nitrogen and the Hay-Wadt small-core effective core potential (ECP) including a double-xi valence basis set for iron, followed by single-point energy refinement with the 6-31G* basis set, is suitable for predicting both the geometries and the spin-states of EDDHA-Fe(III) complexes. The presence of a high-spin iron in Fe(III)-EDDHA complexes could be the key to understanding their lack of reactivity in electron-transfer processes, either chemically or electrochemically induced, and their resistance to photodegradation.

  5. Six-Coordinate Ln(III Complexes with Various Coordination Geometries Showing Distinct Magnetic Properties

    Directory of Open Access Journals (Sweden)

    Mei Guo

    2018-01-01

    Full Text Available The syntheses, structural characterization, and magnetic properties of three lanthanide complexes with formulas [Ln(L13] (Ln = Dy (1Dy; Er (1Er; and [Dy(L22] (2Dy were reported. Complexes 1Dy and 1Er are isostructural with the metal ion in distorted trigonal-prismatic coordination geometry, but exhibit distinct magnetic properties due to the different shapes of electron density for DyIII (oblate and ErIII (prolate ions. Complex 1Dy shows obvious SMM behavior under a zero direct current (dc field with an effective energy barrier of 31.4 K, while complex 1Er only features SMM behavior under a 400 Oe external field with an effective energy barrier of 23.96 K. In stark contrast, complex 2Dy with the octahedral geometry only exhibits the frequency dependence of alternating current (ac susceptibility signals without χ″ peaks under a zero dc field.

  6. Synthesis and physicochemical analysis of Sm (II, III) acetylacetone chelate complexes

    International Nuclear Information System (INIS)

    Kostyuk, N.N.; Dik, T.A.; Trebnikov, A.G.

    2004-01-01

    Sm (II, III) acetylacetone chelate complexes were synthesized by electrochemical method. It was shown that anode dissolution of the metal samarium over acetylacetone leads to formation of the Sm (II, III) chelate complexes: xSm(acac)2 · ySm(acac)3 · zH(acac). Factors x, y and z depend on quantity of the electricity, which flew through the electrolysis cell. The compositions of the obtained substances were confirmed by the physicochemical analysis (ultimate analysis, IR-, mass spectroscopy and thermal analysis (thermogravimetric, isothermal warming-up and differential scanning colorimetry). (Authors)

  7. Complexation of Am(III) by oxalate in NaClO4 media

    International Nuclear Information System (INIS)

    Choppin, G.R.; Chen, J.F.

    1995-01-01

    The complexation of Am(III) by oxalate has been investigated in solutions of NaClO 4 up to 9.0 M ionic strength at 25 degrees C. The dissociation constants of oxalic acid were determined by potentiometric titration, while the stability constants of the Am(III)-oxalate complexation were measured by the solvent extraction technique. A thermodynamic model was constructed to predict the apparent equilibrium constants at different ionic strengths by applying the Pitzer equation using parameters for the Na + -HOx - , Na + -Ox - , AmOx + -ClO 4 - , and Na + -Am(Ox) 2 - interactions obtained by fitting the data

  8. 2,2',-bipyridine and 1,10-phenanthroline complexes of lanthanide(III) trifluoroacetates

    International Nuclear Information System (INIS)

    Misra, S.N.; Singh, M.

    1983-01-01

    The syntheses and characterization of lanthanide(III) triflloroacetate complexes with 2,2'-bipyridine and 1,10-phenanthroline are reported. Lanthanide(III) trifluoroacetates yield compounds of the type Ln(CF 3 COO) 3 .bipy or phen with 2,2'-bipyridine and 1,10-phenanthroline. Their properties and structures have been studied using chemical analyses. electronic and infrared spectra. Thermal analysis of a few complexes have also been done. The infrared data show that the trifluoroacetate group acts as a bidentate ligand making the coordination number of lanthanide eight. (author)

  9. Rare earth(III) complexes for the development of new magnetic and luminescent probes

    International Nuclear Information System (INIS)

    Nonat, A.

    2007-10-01

    The simultaneous optimisation of the molecular parameters determining the relaxivity (number of coordinated water molecules, water-exchange, rotation dynamics of the whole complex, electronic relaxation, Gd(III)-proton distance) is essential to prepare efficient contrast agents. The aim of this work is on the one hand to design and study complexes with a high number of bound water molecules and to understand the influence of the coordination sphere on the stability and on the electronic relaxation and on the other hand, to use the ligand as a chromophore for the development of luminescent probes for biomedical imaging. We present the structure, the stability and the relaxivity of Gd(III) complexes of two series of tripodal ligands containing picolinate units based either on the 1,4,7-tri-aza-cyclononane ring or on a tertiary amine. These complexes show high relaxivity in water and in serum and can establish a non covalent interaction with serum albumin. The interpretation of the water proton relaxivity with the help of new relaxometric methods based on an auxiliary probe solute has allowed us to show that both the presence of the picolinate groups and the 1,4,7-tri-aza-cyclononane framework can lead to Gd(III) complexes with favourable electronic relaxation properties. This ligands have also been used for Eu(III) and Tb(III) complexation leading to strong luminescence in visible light. Other complexes derived from 8-hydroxyquinoline unit which display a very high luminescence in infrared are also studied. (author)

  10. Emission properties of Sm(III) complex having ten-coordination structure

    International Nuclear Information System (INIS)

    Hasegawa, Yasuchika; Tsuruoka, Shin-ichi; Yoshida, Takahiko; Kawai, Hideki; Kawai, Tsuyoshi

    2008-01-01

    Sammarium(III) complex having ten-coordination structure, bis-(1,10-phenanthroline)tris-(hexafluoroacetylacetonato)samarium(III) (Sm(hfa) 3 (phen) 2 ) was prepared by chelation of tris-(hexafluoroacetylacetonato) samarium(III) (Sm(hfa) 3 (H 2 O) 2 ) with 1,10-phenantroline (phen). The characteristic ten-coordination structure of Sm(hfa) 3 (phen) 2 was determined by 1 H NMR and elemental analyses. Strong deep-red emission (λ max =643 nm) and narrow emission band (FWHM=5 nm) of Sm(hfa) 3 (phen) 2 originated from electronic allowed transition from characteristics ten coordinate structure. The emission quantum yields Sm(hfa) 3 (phen) 2 excited at absorption bands of ligands and Sm(III) ion were found to be 0.36 and 1.4%, respectively

  11. Studies of Binary Complexes of Tripodal Ligand cis,cis-1,3,5-tris(methylaminocyclohexane with Cr(III and Fe(III

    Directory of Open Access Journals (Sweden)

    S. Esakki Muthu

    2005-01-01

    Full Text Available The formation of binary complexes of Cr(III and Fe(III with a tripodal ligand cis,cis-1,3,5-tris(methylaminocyclohexane (tmach (L has been investigated in solution. The overall stability constants of tmach with Cr(III and Fe(III were determined by potentiometric method at an ionic strength of 0.1 M NaClO4 at 25±1°C in aqueous medium. The formation of species like MLH25+, MLH4+, ML3+, ML(OH2+ and ML(OH3 were observed. Fe(III was found to form more stable complexes than Cr(III. Molecular mechanics calculations were performed to explain the mode of coordination in solution.

  12. Synthesis, analysis and radiolysis of the cobalt III 8 hydroxyquinolinate complex

    International Nuclear Information System (INIS)

    Mestnik, S.A.C.; Silva, C.P.G. da.

    1981-11-01

    The cobalt III 8-hidroxyquinolinate complex was syntetized from a solution of cobalt II. The compound was analysed by IR absorption spectroscopy, elemental analysis and by the determination of number of ligands. The radiolytic degradation was verified by spectrophotometry after submitting samples of 10 - 3 M complex in ethanolic solution to different doses of gamma radiation from a 60 Co source. The change of maximum absorbance of the complex with different doses of gamma radiation and its UV-VIS absorption spectra are presented. The complex in the solid state was also irradiated with 6,9 Mrad of gamma radiation but it didn't present degradation. (Author) [pt

  13. Characterization of some Pr(III) complexes in terms of electronic spectral parameters

    International Nuclear Information System (INIS)

    Bhati, P.R.; Soni, K.P.; Joshi, G.K.; Swami, S.N.

    1992-01-01

    Pr(III) complexes from the ligands derived from methyl acetoacetate, ethyl acetoacetate, veratraldehyde, ethyl vanillin and 2,5 dimethoxy benzaldehyde forming Schiff-bases with ortho, meta and para phenylene diamines have been synthesized. The complexes have been characterized in terms of various Slater-Condon Lande and Judd-Ofelt parameters. The various trends in the parametric values have also been described. The involvement of 4f-orbital in the Pr(III) complexes including deviation in the symmetry have been discussed on the basis of electronic spectral parameters. The validity of the theories used has been established while comparing observed and calculated energies and intensities of the various bands in the present complexes on the basis of r.m.s deviation. The trends of the curves observed in the solution spectra have also been discussed. (author). 21 refs., 5 tabs., 2 figs

  14. Biological activity of Fe(III) aquo-complexes towards ferric chelate reductase (FCR).

    Science.gov (United States)

    Escudero, Rosa; Gómez-Gallego, Mar; Romano, Santiago; Fernández, Israel; Gutiérrez-Alonso, Ángel; Sierra, Miguel A; López-Rayo, Sandra; Nadal, Paloma; Lucena, Juan J

    2012-03-21

    In this study we have obtained experimental evidence that confirms the high activity of aquo complexes III and IV towards the enzyme FCR, responsible for the reduction of Fe(III) to Fe(II) in the process of iron acquisition by plants. The in vivo FCR assays in roots of stressed cucumber plants have shown a higher efficiency of the family of complexes III and a striking structure-activity relationship with the nature of the substituent placed in a phenyl group far away from the metal center. The results obtained in this work demonstrate that all the aquo compounds tested interact efficiently with the enzyme FCR and hence constitute a new concept of iron chelates that could be of great use in agronomy.

  15. Enantioselective Addition of Allyltin Reagents to Amino Aldehydes Catalyzed with Bis(oxazolinylphenylrhodium(III Aqua Complexes

    Directory of Open Access Journals (Sweden)

    Hisao Nishiyama

    2011-06-01

    Full Text Available Bis(oxazolinylphenylrhodium(III aqua complexes, (PheboxRhX2(H2O [X = Cl, Br], were found to be efficient Lewis acid catalysts for the enantioselective addition of allyl- and methallyltributyltin reagents to amino aldehydes. The reactions proceed smoothly in the presence of 5–10 mol % of (PheboxRhX2(H2O complex at ambient temperature to give the corresponding amino alcohols with modest to good enantioselectivity (up to 94% ee.

  16. 127I Moessbauer study of some oxygen bonded iodine(I) and iodine(III) complexes

    International Nuclear Information System (INIS)

    Bardhan, M.; Birchall, T.; Frampton, C.; Kapoor, P.

    1988-01-01

    127 I Moessbauer spectra have been recorded at 4.2 0 K for a series of oxygen bonded iodine(I) and iodine(III) complexes. The sign of the quadrupole coupling constant is dependant only on the primary arrangement of ligands about the central iodine nucleus whereas the magnitude and the asymmetry parameter are more sensitive to ligand electronegativity and type. (orig.)

  17. Bibenzimidazole containing mixed ligand cobalt(III) complex as a selective receptor for iodide

    Digital Repository Service at National Institute of Oceanography (India)

    Indumathy, R.; Parameswarana, P.S.; Aiswarya, C.V.; Nair, B.U.

    Two new mixed ligand cobalt(III) complexes containing bibenzimidazole (bbenzimH2) ligand with composition [Co(phen)2bbenzimH2](ClO4)3 (1) and [Co(bpy)2bbenzimH2](ClO4...

  18. A Fluorinated Cobalt(III) Porphyrin Complex for Hydroalkoxylation of Alkynes.

    Science.gov (United States)

    Ushimaru, Richiro; Nishimura, Takuho; Iwatsuki, Toshiki; Naka, Hiroshi

    2017-01-01

    A fluorinated cobalt(III) porphyrin complex [Co(TPFPP)NTf 2 ·2C 2 H 5 OH, where TPFPP=5,10,15,20-tetrakis(pentafluorophenyl)porphyrin, Tf=CF 3 SO 2 ] promotes hydroalkoxylation of alkynes to give acetals in good to excellent yields. The acetals can be directly functionalized with nucleophiles in a one-pot procedure.

  19. Synthesis and X-ray structure of the dysprosium(III) complex derived ...

    African Journals Online (AJOL)

    Synthesis and X-ray structure of the dysprosium(III) complex derived from the ligand 5-chloro-1 ... Bulletin of the Chemical Society of Ethiopia ... synthesized and its crystal structure determined by single X-ray diffraction at room temperature.

  20. Synthesis, Physicochemical Properties, and Antimicrobial Studies of Iron (III Complexes of Ciprofloxacin, Cloxacillin, and Amoxicillin

    Directory of Open Access Journals (Sweden)

    Fabian I. Eze

    2014-01-01

    Full Text Available Iron (III complexes of ciprofloxacin, amoxicillin, and cloxacillin were synthesized and their aqueous solubility profiles, relative stabilities, and antimicrobial properties were evaluated. The complexes showed improved aqueous solubility when compared to the corresponding ligands. Relative thermal and acid stabilities were determined spectrophotometrically and the results showed that the complexes have enhanced thermal and acid stabilities when compared to the pure ligands. Antimicrobial studies showed that the complexes have decreased activities against most of the tested microorganisms. Ciprofloxacin complex, however, showed almost the same activity as the corresponding ligand. Job’s method of continuous variation suggested 1 : 2 metals to ligand stoichiometry for ciprofloxacin complex but 1 : 1 for cloxacillin complex.

  1. Dissolution of Fe(III) (hydr) oxides by metal-EDTA complexes

    Science.gov (United States)

    Ngwack, Bernd; Sigg, Laura

    1997-03-01

    The dissolution of Fe(III)(hydr)oxides (goethite and hydrous ferric oxide) by metal-EDTA complexes occurs by ligand-promoted dissolution. The process is initiated by the adsorption of metal-EDTA complexes to the surface and is followed by the dissociation of the complex at the surface and the release of Fe(III)EDTA into solution. The dissolution rate is decreased to a great extent if EDTA is complexed by metals in comparison to the uncomplexed EDTA. The rate decreases in the order EDTA CaEDTA ≫ PbEDTA > ZnEDTA > CuEDTA > Co(II)EDTA > NiEDTA. Two different rate-limiting steps determine the dissolution process: (1) detachment of Fe(III) from the oxide-structure and (2) dissociation of the metal-EDTA complexes. In the case of goethite, step 1 is slower than step 2 and the dissolution rates by various metals are similar. In the case of hydrous ferric oxide, step 2 is rate-limiting and the effect of the complexed metal is very pronounced.

  2. Kinetic of liquid-liquid extraction for uranyl nitrate and actinides (III) and lanthanides (III) nitrates by amide extractants

    International Nuclear Information System (INIS)

    Toulemonde, V.; CEA Centre d'Etudes de la Vallee du Rhone, 30 -Marcoule

    1995-01-01

    The kinetics of liquid-liquid extraction by amide extractants have been investigated for uranyl nitrate (monoamide extractants), actinides (III) and lanthanides (III) nitrates (diamide extractants). The transfer of the metallic species from the aqueous phase to the organic phase was studied using two experimental devices: ARMOLLEX (Argonne Modified Lewis cell for Liquid Liquid Extraction) and RSC (Rotating Stabilized Cell). The main conclusions are: for the extraction of uranyl nitrate by DEHDMBA monoamide, the rate-controlling step is the complexation of the species at the interface of the two liquids. Thus, an absorption-desorption (according to Langmuir theory) reaction mechanism was proposed; for the extraction of actinides (III) and lanthanides (III) nitrates in nitric acid media by DMDBTDMA diamide, the kinetic is also limited by interfacial reactions. The behavior of Americium and Europium is very similar as fare as their reaction kinetics are concerned. (author)

  3. Complexation of the actinides (III, IV and V) with organic acids

    International Nuclear Information System (INIS)

    Leguay, S.

    2012-01-01

    A thorough knowledge of the chemical properties of actinides is now required in a wide variety of fields: extraction processes involved in spent fuel reprocessing, groundwater in the vicinity of radioactive waste packages, environmental and biological media in the case of accidental release of radionuclides. In this context, the present work has been focused on the complexation of Am(III), Cm(III), Cf(III), Pu(IV) and Pa(V) with organic ligands: DTPA, NTA and citric acid. The complexation of pentavalent protactinium with citric and nitrilotriacetic acids was studied using liquid-liquid extraction with the element at tracer scale (C Pa ≤ 10 -10 M). The order and the mean charge of each complex were determined from the analysis of the systematic variations of the distribution coefficient of Pa(V) as function of ligand and proton concentration. Then, the apparent formation constants related of the so-identified complexes were calculated. The complexation of trivalent actinides with DTPA was studied by fluorescence spectroscopy (TRLFS) and capillary electrophoresis (CE-ICP-MS). The coexistence of the mono-protonated and non-protonated complexes (AnHDTPA - and AnDTPA 2- ) in acidic media (1.5 ≤ pH ≤ 3.5) was shown unambiguously. Literature data have been reinterpreted by taking into account both complexes and a consistent set of formation constants of An(III)-DTPA has been obtained. The experimental study was completed by theoretical calculations (DFT) on Cm-DTPA system. The coordination geometry of Cm in CmDTPA 2- and CmHDTPA - including water molecules in the first coordination sphere has been determined as well as interatomic distances. Finally, a study on the complexation of Pu(IV) with DTPA was initiated in order to more closely mimic physiological conditions. A three-step approach was proposed to avoid plutonium hydrolysis: i/ complexation of Pu(IV) with (NTA) in order to protect Pu(IV) from hydrolysis (at low pH) ii/ increase of pH toward neutral conditions

  4. Photoluminescence studies of a Terbium(III) complex as a fluorescent probe for DNA detection

    Energy Technology Data Exchange (ETDEWEB)

    Khorasani-Motlagh, Mozhgan, E-mail: mkhorasani@chem.usb.ac.ir; Noroozifar, Meissam; Niroomand, Sona; Moodi, Asieh

    2013-11-15

    The photoluminescence properties of a Tb(III) complex of the form [Tb(phen){sub 2}Cl{sub 3}·OH{sub 2}] (phen=1,10-phenanthroline) in different solvents are presented. It shows the characteristic luminescence of the corresponding Ln{sup 3+} ion in the visible region. The emission intensity of this complex in coordinating solvent is higher than non-coordinating one. The suggested mechanism for the energy transfer between the ligand and Tb{sup 3+} ion is the intramolecular energy transfer mechanism. The interactions of the Tb(III) complex with fish salmon DNA are studied by fluorescence spectroscopy, circular dichroism study and viscosity measurements. The results of fluorescence titration reveal that DNA strongly quenches the intrinsic fluorescence of the complex through a static quenching procedure. The binding constant (K{sub b}) of the above metal complex at 25 °C is determined by the fluorescence titration method and it is found to be (8.06±0.01)×10{sup 3} M{sup −1}. The thermodynamic parameters (ΔH{sup 0}>0, ΔS{sup 0}>0 and ΔG{sup 0}<0) indicate that the hydrophobic interactions play a major role in DNA–Tb complex association. The results support the claim that the title complex bonds to FS-DNA by a groove mode. -- Highlights: • Photoluminescence of [Tb(phen){sub 2}Cl{sub 3}·OH{sub 2}] in different solvents are studied. • Tb(III) complex shows good binding affinity to FS DNA with K{sub b}=(8.06±0.01)×10{sup 3} M{sup −1}. • Viscosity of DNA almost unchanged by increasing amount of Tb complex. • CD spectrum of DNA has a little change with increasing amount of Tb complex. • Thermodynamic parameters indicate that the binding reaction is entropically driven.

  5. Fermi Surface and Antiferromagnetism in Europium Metal

    DEFF Research Database (Denmark)

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

    1968-01-01

    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...

  6. Spectral, Electrochemical, Fluorescence, Kinetic and Anti-microbial Studies of Acyclic Schiff-base Gadolinium(III) Complexes

    International Nuclear Information System (INIS)

    Vijayaraj, A.; Prabu, R.; Suresh, R.; Narayanan, V.; Sangeetha Kumari, R.; Kaviyarasan, V.

    2012-01-01

    A new series of acyclic mononuclear gadolinium(III) complexes have been prepared by Schiff-base condensation derived from 5-methylsalicylaldehyde, diethylenetriamine, tris(2-aminoethyl) amine, triethylenetetramine, N,N-bis(3-aminopropyl)ethylene diamine, N,N-bis(aminopropyl) piperazine, and gadolinium nitrate. All the complexes were characterized by elemental and spectral analyses. Electronic spectra of the complexes show azomethine (CH=N) within the range of 410-420 nm. The fluorescence efficiency of Gd(III) ion in the cavity was completely quenched by the higher chain length ligands. Electrochemical studies of the complexes show irreversible one electron reduction process around -2.15 to -1.60 V. The reduction potential of gadolinium(III) complexes shifts towards anodic directions respectively upon increasing the chain length. The catalytic activity of the gadolinium(III) complexes on the hydrolysis of 4-nitrophenylphosphate was determined. All gadolinium(III) complexes were screened for antibacterial activity

  7. Spectral, Electrochemical, Fluorescence, Kinetic and Anti-microbial Studies of Acyclic Schiff-base Gadolinium(III) Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Vijayaraj, A.; Prabu, R.; Suresh, R.; Narayanan, V.; Sangeetha Kumari, R.; Kaviyarasan, V. [Univ. of Madras, Madras (India)

    2012-11-15

    A new series of acyclic mononuclear gadolinium(III) complexes have been prepared by Schiff-base condensation derived from 5-methylsalicylaldehyde, diethylenetriamine, tris(2-aminoethyl) amine, triethylenetetramine, N,N-bis(3-aminopropyl)ethylene diamine, N,N-bis(aminopropyl) piperazine, and gadolinium nitrate. All the complexes were characterized by elemental and spectral analyses. Electronic spectra of the complexes show azomethine (CH=N) within the range of 410-420 nm. The fluorescence efficiency of Gd(III) ion in the cavity was completely quenched by the higher chain length ligands. Electrochemical studies of the complexes show irreversible one electron reduction process around -2.15 to -1.60 V. The reduction potential of gadolinium(III) complexes shifts towards anodic directions respectively upon increasing the chain length. The catalytic activity of the gadolinium(III) complexes on the hydrolysis of 4-nitrophenylphosphate was determined. All gadolinium(III) complexes were screened for antibacterial activity.

  8. Molecular magnetism of a linear Fe(III)-Mn(II)-Fe(III) complex. Influence of long-range exchange interaction

    International Nuclear Information System (INIS)

    Lengen, M.; Chaudhuri, P.

    1994-01-01

    The magnetic properties of [L-Fe(III)-dmg 3 Mn(II)-Fe(III)-L] (ClO 4 ) 2 have been characterized by magnetic susceptibility, EPR, and Moessbauer studies. L represents 1,4,7-trimethyl-,1,4,7-triazacyclononane and dmg represents dimethylglyoxime. X-ray diffraction measurements yield that the arrangement of the three metal centers is strictly linear with atomic distances d Fe-Mn 0.35 nm and d Fe-Fe = 0.7 nm. Magnetic susceptibility measurements (3-295 K) were analyzed in the framework of the spin-Hamiltonian formalism considering Heisenberg exchange and Zeeman interaction: H = J Fe-Mn (S Fe1 + S Fe2 )S Mn + J Fe-Fe S Fe1 S Fe2 + gμ B S total B. The spins S Fe1 = S Fe2 = S Mn = 5/2 of the complex are antiferromagnetically coupled, yielding a total spin of S total = 5/2 with exchange coupling constants F Fe-Mn = 13.4 cm -1 and J Fe-Fe = 4.5 cm -1 . Magnetically split Moessbauer spectra were recorded at 1.5 K under various applied fields (20 mT, 170 mT, 4 T). The spin-Hamiltonian analysis of these spectra yields isotropic magnetic hyperfine coupling with A total /(g N μ N ) = -18.5 T. The corresponding local component A Fe is related to A total via spin-projection: A total = (6/7)A Fe . The resulting A Fe /(g N μ N ) -21.6 T is in agreement with standard values of ferric high-spin complexes. Spin-Hamiltonian parameters as obtained from Moessbauer studies and exchange coupling constants as derived from susceptibility measurements are corroborated by temperature-dependent EPR studies. (orig.)

  9. Spectroscopic investigation on the interaction of some surfactant-cobalt(III) complexes with serum albumins

    Energy Technology Data Exchange (ETDEWEB)

    Vignesh, Gopalaswamy; Nehru, Selvan; Manojkumar, Yesaiyan; Arunachalam, Sankaralingam, E-mail: arunasurf@yahoo.com

    2014-01-15

    The interaction of HSA/BSA with single and double chain surfactant-cobalt(III) complexes, cis-[Co(phen){sub 2}(UA)Cl](ClO{sub 4}){sub 2}·2H{sub 2}O (1), cis-[Co(phen){sub 2}(UA){sub 2}](ClO{sub 4}){sub 3}·2H{sub 2}O (2), cis-[Co(en){sub 2}(UA)Cl](ClO{sub 4}){sub 2}·2H{sub 2}O (3), cis-[Co(en){sub 2}(UA){sub 2}](ClO{sub 4}){sub 3}·2H{sub 2}O (4), were investigated by steady state fluorescence, UV–vis absorption, synchronous, three dimensional fluorescence and circular dichroism spectroscopy. The results reveal that the quenching of HSA/BSA by all the four complexes takes place through static mechanism. The binding constant, binding sites and thermodymamic parameter were calculated. The results illustrate that the double chain surfactant-cobalt(III) complexes bind more strongly than the corresponding single chain complexes. The distance between donor (HSA/BSA) and acceptor (surfactant-cobalt(III) complexes) was obtained according to FRET. The results of synchronous, three dimensional and circular dichroism spectroscopy studies show that all the complexes caused considerable amount of conformational and some amount of environment changes in HSA/BSA. -- Highlights: • Binding of single and double chain surfactant-cobalt(III) complexes with serum albumins. • Hydrophobic attraction plays a major role in the binding process. • Binding induces considerable amount of conformational changes in the protein.

  10. 2 : 2 Fe(III): ligand and "adamantane core" 4 : 2 Fe(III): ligand (hydr)oxo complexes of an acyclic ditopic ligand

    DEFF Research Database (Denmark)

    Ghiladi, Morten; Larsen, Frank B.; McKenzie, Christine J.

    2005-01-01

    A bis-hydroxo-bridged diiron(III) complex and a bis-mu-oxo-bis-mu-hydroxo-bridged tetrairon( III) complex are isolated from the reaction of 2,6-bis((N, N'-bis-(2-picolyl) amino) methyl)-4-tert-butylphenol (Hbpbp) with iron perchlorate in acidic and neutral solutions respectively. The X-ray struct......A bis-hydroxo-bridged diiron(III) complex and a bis-mu-oxo-bis-mu-hydroxo-bridged tetrairon( III) complex are isolated from the reaction of 2,6-bis((N, N'-bis-(2-picolyl) amino) methyl)-4-tert-butylphenol (Hbpbp) with iron perchlorate in acidic and neutral solutions respectively. The X...

  11. Formation constants of lanthanide(III)- aminopolycarboxylate- ATP mixed ligand complexes and their systematics

    International Nuclear Information System (INIS)

    Verma, Sangeeta; Limaye, S.N.; Saxena, M.C.

    1993-01-01

    Formation constants (log Ksub(MAL)sup(MA), log Ksub(ML)sup(M) and log Ksub(ML)sup(ML) of mixed ligand lanthanide(III) complexes of the type [Ln(III).A.ATP[ 2 , where LN(III)=La 3+ , Ce 3+ , Pr 3+ , Nd 3+ , Sm 3+ , Eu 3+ , Gd 3+ , Tb 3+ or Dy 3+ ' A=NTA(nitrilotriacetate) or HEDTA (2-hydroxyethylethylenediamine triacetate) and ATP=adenosine 5'-triphosphate (L), and of the binary [Ln(III).ATP[ and [Ln(III).(ATP) 2 [ complexes have been determined by potentiometric pH titrations using the Irving-Rossotti approach at three temperatures 20, 30 and 40 degC and at a fixed ionic strength, I=0.2 mol dm -3 (NAclO 4 ). The solution stabilities (log Ksub(MAL)sup(MA) values) are influenced by the electrostatic effect involved in ternary complexation and increase with temperature. The enthalpy factor (ΔH) has been found to be small but unfavourable and the entropy factor (ΔS) large and favourable. The log Ksub(MAL)sup(MA) values lie in the order NTA>HEDTA with respect to A and La 3+ 3+ 3+ 3+ 3+ 3+ >Gd 3+ 3+ 3+ with respect to lanthanides. Tetrad effect is present in the formation constant values; its magnitude has been found to lie in the sequence f 7 >f 3 -f 4 ≅ f 10 -f 11 for the Ln(III) ions. Systematics in the formation constant values has been further studied by evaluating changes in the inter-electronic repulsion Racah parameters, extra stabilisation of specific 4f 9 -configurations and nephelauxetic ratio using experimental values of the formation constants. (author). 24 refs., 2 figs., 3 tabs

  12. Spectroscopic investigations on the complexation of Cm(III) and Eu(III) with organic model ligands and their binding mode in human urine (in vitro)

    International Nuclear Information System (INIS)

    Heller, Anne

    2011-01-01

    In case of incorporation, trivalent actinides (An(III)) and lanthanides (Ln(III)) pose a serious health risk to humans. An(III) are artificial, highly radioactive elements which are mainly produced during the nuclear fuel cycle in nuclear power plants. Via hazardous accidents or nonprofessional storage of radioactive waste, they can be released in the environment and enter the human food chain. In contrast, Ln(III) are nonradioactive, naturally occurring elements with multiple applications in technique and medicine. Consequently it is possible that humans get in contact and incorporate both, An(III) and Ln(III). Therefore, it is of particular importance to elucidate the behaviour of these elements in the human body. While macroscopic processes such as distribution, accumulation and excretion are studied quite well, knowledge about the chemical binding form (speciation) of An(III) and Ln(III) in various body fluids is still sparse. In the present work, for the first time, the speciation of Cm(III) and Eu(III) in natural human urine (in vitro) has been investigated spectroscopically and the formed complex identified. For this purpose, also basic investigations on the complex formation of Cm(III) and Eu(III) in synthetic model urine as well as with the urinary relevant, organic model ligands urea, alanine, phenylalanine, threonine and citrate have been performed and the previously unknown complex stability constants determined. Finally, all experimental results were compared to literature data and predictions calculated by thermodynamic modelling. Since both, Cm(III) and Eu(III), exhibit unique luminescence properties, particularly the suitability of time-resolved laser-induced fluorescence spectroscopy (TRLFS) could be demonstrated as a method to investigate these metal ions in untreated, complex biofluids. The results of this work provide new scientific findings on the biochemical reactions of An(III) and Ln(III) in human body fluids on a molecular scale and

  13. Complexation equilibria and spectrophotometric determination of iron(III) with 1-amino-4-hydroxyanthraquinone.

    Science.gov (United States)

    Abu-Bakr, M S; Sedaira, H; Hashem, E Y

    1994-10-01

    The complex equilibria of iron(III) with 1-amino-4-hydroxyanthraquinone (AMHA) were studied spectrophotometrically in 40% (v/v) ethanol and an ionic strength of 0.1M (NaClO(4)). The complexation reactions were demonstrated and characterized using graphical logarithmic analysis of the absorbance-pH graphs. A simple, rapid, selective and sensitive method for the spectrophotometric determination of trace amounts of Fe(III) is developed based on the formation of Fe(AMHA) complex at pH 2.5 (lambda(max) = 640 nm, epsilon approximately = 2.1 x 10(4) L. mol(-1) . cm(-1)) in the presence of a large number of foreign ions. Interferences caused by palladium(II) was masked by the addition of cyanide ions. The method has been applied to the determination of iron in some synthetic samples and polymetallic iron ores.

  14. Synthesis and Luminescence Properties of Iridium(III Azide- and Triazole-Bisterpyridine Complexes

    Directory of Open Access Journals (Sweden)

    Timothy W. Schmidt

    2013-07-01

    Full Text Available We describe here the synthesis of azide-functionalised iridium(III bisterpyridines using the “chemistry on the complex” strategy. The resulting azide-complexes are then used in the copper(I-catalysed azide-alkyne Huisgen 1,3-dipolar cycloaddition “click chemistry” reaction to from the corresponding triazole-functionalised iridium(III bisterpyridines. The photophysical characteristics, including lifetimes, of these compounds were also investigated. Interestingly, oxygen appears to have very little effect on the lifetime of these complexes in aqueous solutions. Unexpectedly, sodium ascorbate acid appears to quench the luminescence of triazole-functionalised iridium(III bisterpyridines, but this effect can be reversed by the addition of copper(II sulfate, which is known to oxidize ascorbate under aerobic conditions. The results demonstrate that iridium(III bisterpyridines can be functionalized for use in “click chemistry” facilitating the use of these photophysically interesting complexes in the modification of polymers or surfaces, to highlight just two possible applications.

  15. Synthesis of Cr(III-Morin Complex: Characterization and Antioxidant Study

    Directory of Open Access Journals (Sweden)

    Qadeer K. Panhwar

    2014-01-01

    Full Text Available The complex formation between Cr(III and morin was carried out in methanol and confirmed by analytical characterization using UV-Vis, IR, 1H NMR, and TG-DTA. UV-Vis shows significant bathochromic shift in benzoyl upon coordination as well as IR well illustrates the peak shift of C=O group and formation of a O–Cr(III bond. Likewise, 1H NMR studies clarify that Cr(III metal ion replaces the 5OH proton hence; 5-hydroxy-4-keto site is employed by morin in chelation to form six-membered stable ring system out of three available chelating sites. In addition, TG-DTA denotes the presence of coordinated and crystalline water molecules. The melting point of the complex was found to be 389°C by DSC. In addition, Cr(III-morin complex was found to be a more potent antioxidant than morin as evaluated by DPPH• and FRAP methods.

  16. Bicarbonate catalysis of exchange synthesis of [51Cr]Cr(III)-EDTA and other chromium complexes

    International Nuclear Information System (INIS)

    Aronson, F.L.; Strashun, A.M.; Lopez, C.; Steigman, J.

    1993-01-01

    Exchange syntheses of trivalent chromium complexes often require heating, thus limiting tagging of heat-sensitive biological compounds with 51 Cr. Bicarbonate at pH 6, accelerates the formation of mM Cr-EDTA. Accordingly, room temperature catalysis with [ 51 Cr]Cr(III) at 10 -7 -10 -8 M was investigated. Complexes were successfully formed with EDTA and iminodiacetic acid (electrophoretic analysis) and acetylacetone and tropolone (analyzed by chloroform extraction). The formation of these complexes normally requires extensive heating. (author)

  17. Complexes of molybdenum(III) with 2-(2'-pyridyl)benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, S P [Patna Univ. (India). Dept. of Chemistry; Prasad, K M [H.D. Jain Coll., Arrah (India). Dept. of Chemistry

    1979-07-01

    Molybdenum(III) forms with 2-(2'-pyridyl) benzimidazole(LH) the trischelated complexes, (Mo(LH)/sub 3/)X/sub 3/ as well as the cationic-anionic complexes, (Mo(LH)/sub 3/X/sub 2/)/sup +/ (Mo(LH)X/sub 4/)/sup -/(X=Cl/sup -/,Br/sup -/ or NCS/sup -/), depending on pH. These complexes have been synthesised and characterised from elemental analyses, i.r. and electronic spectra, magnetic moments and molar conductance.

  18. Single-molecule magnetism in three related {Co(III)2Dy(III)2}-acetylacetonate complexes with multiple relaxation mechanisms.

    Science.gov (United States)

    Langley, Stuart K; Chilton, Nicholas F; Moubaraki, Boujemaa; Murray, Keith S

    2013-06-17

    Three new heterometallic complexes with formulas of [Dy(III)2Co(III)2(OMe)2(teaH)2(acac)4(NO3)2] (1), [Dy(III)2Co(III)2(OH)2(teaH)2(acac)4(NO3)2]·4H2O (2), and [Dy(III)2Co(III)2(OMe)2(mdea)2(acac)4(NO3)2] (3) were characterized by single-crystal X-ray diffraction and by dc and ac magnetic susceptibility measurements. All three complexes have an identical "butterfly"-type metallic core that consists of two Dy(III) ions occupying the "body" position and two diamagnetic low-spin Co(III) ions occupying the outer "wing-tips". Each complex displays single-molecule magnet (SMM) behavior in zero applied magnetic field, with thermally activated anisotropy barriers of 27, 28, and 38 K above 7.5 K for 1-3, respectively, as well as observing a temperature-independent mechanism of relaxation below 5 K for 1 and 2 and at 3 K for 3, indicating fast quantum tunneling of magnetization (QTM). A second, faster thermally activated relaxation mechanism may also be active under a zero applied dc field as derived from the Cole-Cole data. Interestingly, these complexes demonstrate further relaxation modes that are strongly dependent upon the application of a static dc magnetic field. Dilution experiments that were performed on 1, in the {Y(III)2Co(III)2} diamagnetic analog, show that the slow magnetic relaxation is of a single-ion origin, but it was found that the neighboring ion also plays an important role in the overall relaxation dynamics.

  19. Factors Affecting the Efficiency of Excited-States Interactions of Complexes between Some Visible Light-Emitting Lanthanide Ions and Cyclophanes Containing Spirobiindanol Phosphonates

    Directory of Open Access Journals (Sweden)

    M. S. Attia

    2007-01-01

    Full Text Available The efficiency of excited-states interactions between lanthanide ions Tb3+ and Eu3+ and some new cyclophanes (I, II, and III has been studied in different media. High luminescence quantum yield values for terbium and europium complexes in DMSO and PMMA were obtained. The photophysical properties of the green and red emissive Tb3+ and Eu3+ complexes have been elucidated, respectively.

  20. Improved Antileishmanial Activity of Dppz through Complexation with Antimony(III and Bismuth(III: Investigation of the Role of the Metal

    Directory of Open Access Journals (Sweden)

    Cynthia Demicheli

    2012-10-01

    Full Text Available Two novel trivalent antimony(III and bismuth(III complexes with the nitrogen-donor heterocyclic ligand dipyrido[3,2-a:2',3'-c]phenazine (dppz were synthesized and characterized as [Sb(dppzCl3]∙H2O∙CH3OH and [Bi(dppzCl3]. The crystal structure of Sb(III complex was determined by X-ray crystallography. These complexes were evaluated for their activity against the promastigote form of Sb(III-sensitive and –resistant Leishmania infantum chagasi and Leishmania amazonensis strains. Both complexes were more effective than dppz alone in inhibiting the growth of Leishmania promastigotes and were at least 77 and 2,400 times more active than potassium antimonyl tartrate in Sb(III-sensitive and -resistant Leishmania, respectively. The cytotoxicity of dppz and its complexes against mouse peritoneal macrophages occurred at dppz concentrations at least 6-fold greater than those found to be active against Leishmania promastigotes.To investigate the role of the metal in the improved antileishmanial activity of dppz, the activity of the Sb(III complex was compared between the Sb-resistant mutants and their respective parental sensitive strains. The lack of cross-resistance to the Sb(III-dppz complex together with the much lower activity of antimonyl tartrate, SbCl3 and BiCl3 strongly support the model that the metal is not active by itself but improves the activity of dppz through complexation.

  1. Type III odontoid fractures: A subgroup analysis of complex, high-energy fractures treated with external immobilization

    Directory of Open Access Journals (Sweden)

    Thomas E Niemeier

    2018-01-01

    Conclusions: Complex Type III odontoid fractures are distinctly different from low-energy injuries. In the current study, 21% of patients were unsuccessfully treated nonoperatively with external immobilization and required surgery. For complex Type III fractures, we recommend initial conservative treatment, while maintaining close monitoring throughout patient recovery and fracture union.

  2. Uranyl(VI) and lanthanum(III) complexes with functionalized macrocyclic and macroacyclic Schiff bases

    International Nuclear Information System (INIS)

    Aguiari, A.; Brianese, N.; Tamburini, S.; Vigato, P.A.

    1995-01-01

    Acyclic Schiff bases have been prepared by [2 + 1] condensation of 2,6-diformyl-4-chlorophenol and H 2 NCH 2 [CH 2 XCH 2 ] n CH 2 NH 2 (n =3D 0 H 2 -I; X =3D NH, S, O n =3D 1 H 2 -II...H 2 -IV; X =3D 0 n =3D 2 H 2 -V; X =3D 0 n =3D 3 H 2 -VI). The related uranlyl(VI) and lanthanum (III) complexes have bee synthesized by reaction by reaction of the preformed ligands with the appropriate salt or by the template procedure, in the presence of base. No base was employed in the preparation of lanthanum (III) complexes, La(H 2 -II)(NO 3 ) 3 , La(H 2 -IV)(NO 3 ) 3 where the Schiff bases coordinate as neutral chelate ligands. These acyclic complexes have been used for further condensation, and symmetric and asymmetric cyclic complexes have been obtained by their reaction with the polyamines H 2 NCH 2 [CH 2 XCH 2 ]nCH 2 NH 2 or with 4,4'-diaminodibenzo -18-crown-6. By reaction with 4-aminobenzo-15-crown-5 or 2-amino-methyl-15-crown-5, the same acyclic complexes give rise to functionalized complexes bearing crown-ether moieties. Analogously, the acyclic ligand H 3 -IXX, prepared by condensation of 2,6 diformyl-4-chlorophenol and tris(aminoethyl)amine, forms mono and homodinuclear lanthanum (III) complexes, which may undergo further condensation when reacted with primary functionalized amines. (authors). 42 refs., 2 figs., 2 schemes, 1 tab

  3. Novel synergism by complex ligands in solvent extraction of rare earth metals(III) with β-diketones

    International Nuclear Information System (INIS)

    Imura, H.; Ebisawa, M.; Kato, M.; Ohashi, K.

    2006-01-01

    The extraction of rare earth metals(III) (RE) with hexafluoroacetylacetone (Hhfa) and 2-thenoyltrifluoroacetone (Htta) was studied in the presence of some cobalt(III) chelates such as tris(acetylacetonato)cobalt(III), tris(4-isopropyltropolonato)cobalt(III), tris(8-quinolinolato)cobalt(III), tris(8-quinolinethiolato)cobalt(III), and tris(diethyldithiocarbamato)cobalt(III) in benzene or toluene. The synergistic enhancement of the extraction of RE, especially of lanthanum(III) was found in all the systems. Therefore, those cobalt(III) chelates act as synergists or complex ligands. The equilibrium analysis and IR spectroscopic study were performed to evaluate the present synergistic mechanism. It was found that the RE-β-diketone chelates form 1:1 adducts, i.e., binuclear complexes, with the cobalt(III) chelates in the organic phase. The formation constants (β s,1 ) were determined and compared with those reported previously. The spectroscopic studies demonstrated that adducts have two different structures with inner- and outer-sphere coordination. In the former the cobalt(III) chelate directly coordinated to the RE ion and displaced the coordinated water molecules. In the latter the hydrogen-bonding was formed between the coordinating oxygen or sulfur atoms of cobalt(III) chelate and hydrogen atoms of the coordinated water molecules in the RE-β-diketone chelate. The types of the adducts are mainly due to the steric factors of the RE-β-diketone chelates and the cobalt(III) chelates

  4. Extraction of europium with thenoyltrifluoroacetone into alcohol, ketone and ester solvents

    International Nuclear Information System (INIS)

    Akiba, K.; Kanno, T.

    1980-01-01

    The effect of solvent has been studied on the extraction of tris-thenoyltrifluoroacetone (TTA) chelate of europium(III). Donor-active solvents (S) greatly promote the extraction owing to the formation of solvate species EuA 3 .mS (m = 1,2). Linear relations were established between the distribution of ratios of europium (Dsub(Eu)) and the partition constants of TTA (Psub(HA)); log Dsub(Eu) (at a definite pA) = a log Psub(HA) + b, where constants a and b were empirically determined for each series of solvents. The regularity is interpreted in terms of dual roles of solvent as donor and as medium. (author)

  5. Colorimetric and luminescent bifunctional iridium(III) complexes for the sensitive recognition of cyanide ions

    Science.gov (United States)

    Chen, Xiudan; Wang, Huili; Li, Jing; Hu, Wenqin; Li, Mei-Jin

    2017-02-01

    Two new cyclometalated iridium(III) complexes [(ppy)2Irppz]Cl (1) and [(ppy)2Irbppz]Cl (2) (where ppy = 2-phenylpyridine, ppz = 4,7-phenanthrolino-5,6:5,6-pyrazine, bppz = 2.3-di-2-pyridylpyrazine), were designed and synthesized. The structure of [(ppy)2Irppz]Cl was determined by single crystal X-ray diffraction. Their photophysical properties were also studied. This kind of complexes could coordinate with Cu2 +, the photoluminescence (PL) of the complex was quenched, and the color changed from orange-red to green. The forming M-Cu (M: complexes 1 and 2) ensemble could be further utilized as a colorimetric and emission ;turn-on; bifunctional detection for CN-, especially for complex 1-Cu2 + showed a high sensitivity toward CN- with a limit of diction is 97 nM. Importantly, this kind of iridium(III) complexes shows a unique recognition of cyanide ions over other anions which makes it an eligible sensing probe for cyanide ions.

  6. Syntheses and luminescence properties of two novel lanthanide (III) perchlorate complexes with phenacyl p-tolyl sulfoxide

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Shu-Yan [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China); Li, Wen-Xian, E-mail: nmglwx@163.com [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China); Zheng, Yu-Shan [Inner Mongolia Autonomous Region Product Quality Inspection Institute, Hohhot 010070 (China); Xin, Xiao-Dong; Guo, Feng; Cao, Xiao-Fang [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China)

    2015-06-15

    Two novel solid binary complexes of rare earth perchlorate with phenacyl p-tolyl sulfoxide were synthesized and characterized by elemental analysis, molar conductivity, coordination titration analysis, IR, TG-DSC, {sup 1}HNMR and UV spectra. The results indicated that the composition of these complexes was REL{sub 7} (ClO{sub 4}){sub 3}·6H{sub 2}O (RE=Eu (III), Tb (III), L=C{sub 6}H{sub 5}COCH{sub 2}SOC{sub 6}H{sub 4}CH{sub 3}). The study on IR spectra and {sup 1}HNMR spectra revealed that phenacyl p-tolyl sulfoxide bonded with RE{sup 3+} ions by the oxygen atom in sulfinyl group. The emission spectra illustrated that both the Eu (III) and Tb (III) complexes displayed excellent luminescence in solid state, and The most intensive characteristic emission of the Eu(III) and Tb(III) complexes were 245,400 a.u. and 298,000 a.u. respectively. The slit with was 1 nm. By analysis luminescence and phosphorescence spectrum, it was found that the ligand had the advantage to absorb energy and transfer it to the Eu (III) and Tb (III) ions. The fluorescence lifetimes of the complexes were measured as well as the quantum yield of the Eu (III) complex.

  7. Interactions of trivalent and tetravalent heavy metal-siderophore complexes with pseudomonas fluorescens

    International Nuclear Information System (INIS)

    Yoshida, T.; Ozaki, T.; Ohnuki, T.; Francis, A.J.

    2004-01-01

    We investigated the interactions of the Fe(III)-, Eu(III)-, and Hf(IV)-desferrioxamine B (DFO) complexes with the Gram-negative aerobic bacterium Pseudomonas fluorescens. Potentiometric titration of 1:1 Fe(III)-, Eu(III)-, and Hf(IV)-DFO complexes showed that Hf(IV) formed a strong complex with DFO whose stability was comparable to that of the Fe(III)-DFO complex, while Eu(III) formed a weaker one. DFO in a growth medium was not degraded by P. fluorescens. Contact of P. fluorescens cells with the Fe(III)-, Eu(III)-, and Hf(IV)-DFO complexes at pH 4-9 revealed that there was negligible adsorption of Hf(IV) and Fe(III), whereas Eu(III) was dissociated from DFO and was readily adsorbed by the cells. These results suggest that Fe(III) and Hf(IV) form stable complexes with DFO and are not adsorbed by P. fluorescens cells. Europium(III) forms a weaker complex with DFO than Fe(III) and Hf(IV) do and its DFO complex is readily dissociated in the presence of the cells. (orig.)

  8. Environmentally-relevant concentrations of Al(III) and Fe(III) cations induce aggregation of free DNA by complexation with phosphate group.

    Science.gov (United States)

    Qin, Chao; Kang, Fuxing; Zhang, Wei; Shou, Weijun; Hu, Xiaojie; Gao, Yanzheng

    2017-10-15

    Environmental persistence of free DNA is influenced by its complexation with other chemical species and its aggregation mechanisms. However, it is not well-known how naturally-abundant metal ions, e.g., Al(III) and Fe(III), influence DNA aggregation. This study investigated aggregation behaviors of model DNA from salmon testes as influenced by metal cations, and elucidated the predominant mechanism responsible for DNA aggregation. Compared to monovalent (K + and Na + ) and divalent (Ca 2+ and Mg 2+ ) cations, Al(III) and Fe(III) species in aqueous solution caused rapid DNA aggregations. The maximal DNA aggregation occurred at 0.05 mmol/L Al(III) or 0.075 mmol/L Fe(III), respectively. A combination of atomic force microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy revealed that Al(III) and Fe(III) complexed with negatively charged phosphate groups to neutralize DNA charges, resulting in decreased electrostatic repulsion and subsequent DNA aggregation. Zeta potential measurements and molecular computation further support this mechanism. Furthermore, DNA aggregation was enhanced at higher temperature and near neutral pH. Therefore, DNA aggregation is collectively determined by many environmental factors such as ion species, temperature, and solution pH. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Heptachlor induced mitochondria-mediated cell death via impairing electron transport chain complex III

    International Nuclear Information System (INIS)

    Hong, Seokheon; Kim, Joo Yeon; Hwang, Joohyun; Shin, Ki Soon; Kang, Shin Jung

    2013-01-01

    Highlights: •Heptachlor inhibited mitochondrial electron transport chain complex III activity. •Heptachlor promoted generation of reactive oxygen species. •Heptachlor induced Bax activation. •Heptachlor induced mitochondria-mediated and caspase-dependent apoptosis. -- Abstract: Environmental toxins like pesticides have been implicated in the pathogenesis of Parkinson’s disease (PD). Epidemiological studies suggested that exposures to organochlorine pesticides have an association with an increased PD risk. In the present study, we examined the mechanism of toxicity induced by an organochlorine pesticide heptachlor. In a human dopaminergic neuroblastoma SH-SY5Y cells, heptachlor induced both morphological and functional damages in mitochondria. Interestingly, the compound inhibited mitochondrial electron transport chain complex III activity. Rapid generation of reactive oxygen species and the activation of Bax were then detected. Subsequently, mitochondria-mediated, caspase-dependent apoptosis followed. Our results raise a possibility that an organochlorine pesticide heptachlor can act as a neurotoxicant associated with PD

  10. Synthesis and characterization of Mn(III) chloro complexes with salen-type ligands

    International Nuclear Information System (INIS)

    Byun, Jong Chul; Han, Chung Hun; Lee, Nam Ho; Baik, Jong Seok; Park, Yu Chul

    2002-01-01

    A series of novel salen-type complexes ((Mn(III)(L acn )Cl): n=1∼11) containing Cl - ion were obtained by reactions of the Mn(CH 3 COO) 2 ·4H 2 O with the potentially tetradentate compartmental ligand (H 2 L acn ), prepared by condensation the of one mole of diamine (ethylenediamine, 1,3-propanediamine, o-phenylenediamine, and 2,2-dimethyl-1,3-propanediamine) with two moles of aldehyde (salicylaldehyde, 5-chloro- salicylaldehyde, 3,5-dichlorosalicylal-dehyde, and 3,5-di-tert-butyl-2-hydroxy-benzaldehyde) in a methanol solution . The resulting salen-type ligands and their Mn(III) complexes were identified and characterized by elemental analysis, conductivity, thermogravimetry and UV-VIS, IR, and NMR spectroscopy

  11. Novel polymer anchored Cr(III) Schiff base complexes: Synthesis, characterization and antimicrobial properties

    Science.gov (United States)

    Selvi, Canan; Nartop, Dilek

    2012-09-01

    New polymer-bound Schiff bases and Cr(III) complexes have been synthesized by the reaction of 4-benzyloxybenzaldehyde, polymer-bound with 2-aminophenol, 2-amino-4-chlorophenol and 2-amino-4-methylphenol. The structure of polymeric-Schiff bases and their Cr(III) complexes have been characterized by elemental analyses, magnetic measurements, IR, UV-Vis, TG-DTA and 1H-NMR. All these compounds have also been investigated for antibacterial activity by the well-diffusion method against Staphylococcus aureus (RSKK-07035), Shigella dysenteria type 10 (RSKK 1036), Listeria monocytogenes 4b(ATCC 19115, Escherichia coli (ATCC 1230), Salmonella typhi H (NCTC 901.8394), Staphylococcus epidermis (ATCC 12228), Brucella abortus (RSKK-03026), Micrococcs luteus (ATCC 93419, Bacillus cereus sp., Pseudomonas putida sp. and for antifungal activity against Candida albicans (Y-1200-NIH).

  12. Exploring the Photoreduction of Au(III) Complexes in the Gas-Phase

    Science.gov (United States)

    Marcum, Jesse C.; Kaufman, Sydney H.; Weber, J. Mathias

    2010-06-01

    We have used photodissociation spectroscopy to probe the electronic structure and photoreduction of Au(III) in gas-phase complexes containing Cl- and OH-. The gas-phase electronic spectrum of [AuCl_4]- closely resembles the aqueous solution spectrum, showing a lack of strong solvatochromic shifts. Substitution of Cl- ligands with OH- results in a strong blue shift, in agreement with ligand-field theory. Upon excitation, [AuCl_4]- can dissociate by loss of either one or two neutral Cl atoms, resulting in the reduction of gold from Au(III) to Au(II) and Au(I) respectively. The hydroxide substituted complex, [AuCl_2(OH)_2]-, demonstrates similar behavior but the only observable fragment channel is the loss of two neutral OH ligands, leading only to Au(I).

  13. Heptachlor induced mitochondria-mediated cell death via impairing electron transport chain complex III

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seokheon; Kim, Joo Yeon; Hwang, Joohyun [Department of Molecular Biology, Sejong University, Seoul 143-747 (Korea, Republic of); Shin, Ki Soon [Department of Biology, Department of Life and Nanopharmaceutical Sciences, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Kang, Shin Jung, E-mail: sjkang@sejong.ac.kr [Department of Molecular Biology, Sejong University, Seoul 143-747 (Korea, Republic of)

    2013-08-09

    Highlights: •Heptachlor inhibited mitochondrial electron transport chain complex III activity. •Heptachlor promoted generation of reactive oxygen species. •Heptachlor induced Bax activation. •Heptachlor induced mitochondria-mediated and caspase-dependent apoptosis. -- Abstract: Environmental toxins like pesticides have been implicated in the pathogenesis of Parkinson’s disease (PD). Epidemiological studies suggested that exposures to organochlorine pesticides have an association with an increased PD risk. In the present study, we examined the mechanism of toxicity induced by an organochlorine pesticide heptachlor. In a human dopaminergic neuroblastoma SH-SY5Y cells, heptachlor induced both morphological and functional damages in mitochondria. Interestingly, the compound inhibited mitochondrial electron transport chain complex III activity. Rapid generation of reactive oxygen species and the activation of Bax were then detected. Subsequently, mitochondria-mediated, caspase-dependent apoptosis followed. Our results raise a possibility that an organochlorine pesticide heptachlor can act as a neurotoxicant associated with PD.

  14. Some mixed ligand hydridocarbonyl and hydridophosphine complexes of ruthenium(II) and iridium(III)

    International Nuclear Information System (INIS)

    Pandey, R.N.; Kumar, Sunil; Kumar, Arun; Kumar, S.K.

    1993-01-01

    Mixed-ligand hydridocarbonyl and hydridophosphine complexes of Ru II and Ir III have been isolated from the displacement reaction of [RuH(CO)(Pφ 3 ) 3 Cl] with ligand isonicotinic acid hydrazide (INAH) in benzene medium. Most probable structures are assigned on the basis of elemental analysis, electronic, infrared and far-infrared spectral studies. In all cases bonding of INAH occurs through amino nitrogen of hydrazine residue. (author). 15 refs., 1 tab

  15. Synthesis and structures of a pincer-type rhodium(iii) complex: reactivity toward biomolecules.

    Science.gov (United States)

    Milutinović, Milan M; Bogojeski, Jovana V; Klisurić, Olivera; Scheurer, Andreas; Elmroth, Sofi K C; Bugarčić, Živadin D

    2016-10-04

    A novel rhodium(iii) complex [Rh III (H 2 L tBu )Cl 3 ] (1) (H 2 L tBu = 2,6-bis(5-tert-butyl-1H-pyrazol-3-yl)pyridine) containing a pincer type, tridentate nitrogen-donor chelate system was synthesized. Single crystal X-ray structure analysis revealed that 1 crystallizes in the orthorhombic space group Pbcn with a = 20.7982(6), b = 10.8952(4), c = 10.9832(4) Å, V = 2488.80(15) Å 3 , and eight molecules in the unit cell. The rhodium center in the complex [Rh III (H 2 L tBu )Cl 3 ] (1) is coordinated in a slightly distorted octahedral geometry by the tridentate N,N,N-donor and three chloro ligands, adopting a mer arrangement with an essentially planar ligand skeleton. Due to the tridentate coordination of the N,N,N-donor, the central nitrogen atom N1 is located closer to the Rh III center. The reactivity of the synthesized complex toward small biomolecules (l-methionine (l-Met), guanosine-5'-monophosphate (5'-GMP), l-histidine (l-His) and glutathione (GSH)) and to a series of duplex DNAs and RNA was investigated. The order of reactivity of the studied small biomolecules is: 5'-GMP > GSH > l-Met > l-His. Duplex RNA reacts faster with the [Rh III (H 2 L tBu )Cl 3 ] complex than duplex DNA, while shorter duplex DNA (15mer GG) reacts faster compared with 22mer GG duplex DNA. In addition, a higher reactivity is achieved with a DNA duplex with a centrally located GG-sequence than with a 22GTG duplex DNA, in which the GG-sequence is separated by a T base. Furthermore, the interaction of this metal complex 1 with calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) was examined by absorption (UV-Vis) and emission spectral studies (EthBr displacement studies). Overall, the studied complex exhibited good DNA and BSA interaction ability.

  16. Fe (III - Galactomannan Solid and Aqueous Complexes: Potentiometric, EPR Spectroscopy and Thermal Data

    Directory of Open Access Journals (Sweden)

    Mercê Ana L. R.

    2001-01-01

    Full Text Available Galactomannans can be employed in food industries to modify the final rheological properties of the products. Since they are not absorbed by the living organisms they can also be used in dietary foods. The equilibria involving the interactions of Fe(III and galactomannans and arabinogalactan of several leguminous plants were characterized by potentiometric titrations and EPR spectroscopy. The log of the equilibrium constants for the formation of ML species, where M is the metal ion and L is the monomeric unit of the biopolymers, were 15.4, 14.1 and 18.5, for the galactomannans of C. fastuosa, L. leucocephala and S. macranthera, respectively. Log K values for protonated species (MHL were 3.1, 3.3, and were not detected for the galactomannan of S. macranthera. The log K values for the formation of ML2 were 14.1, 13.3 and 15.2, respectively. Early formation of insoluble products in the equilibrium with arabinogalactan and Fe(III prevented acquisition of reliable data. The solid complexes assays showed a great dipolar interaction between two Fe(III ions in the inner structure of the biopolymer which increased as the degree of substitution of the galactomannan decreased, and also showed the resulting thermal stability. The complexes impart a new possibility of providing essential metal ions in dietary foods since decomplexation of the complexes can occur at different pH values existing in the human body.

  17. Colorimetric method for enzymatic screening assay of ATP using Fe(III)-xylenol orange complex formation.

    Science.gov (United States)

    Ishida, Akihiko; Yamada, Yasuko; Kamidate, Tamio

    2008-11-01

    In hygiene management, recently there has been a significant need for screening methods for microbial contamination by visual observation or with commonly used colorimetric apparatus. The amount of adenosine triphosphate (ATP) can serve as the index of a microorganism. This paper describes the development of a colorimetric method for the assay of ATP, using enzymatic cycling and Fe(III)-xylenol orange (XO) complex formation. The color characteristics of the Fe(III)-XO complexes, which show a distinct color change from yellow to purple, assist the visual observation in screening work. In this method, a trace amount of ATP was converted to pyruvate, which was further amplified exponentially with coupled enzymatic reactions. Eventually, pyruvate was converted to the Fe(III)-XO complexes through pyruvate oxidase reaction and Fe(II) oxidation. As the assay result, yellow or purple color was observed: A yellow color indicates that the ATP concentration is lower than the criterion of the test, and a purple color indicates that the ATP concentration is higher than the criterion. The method was applied to the assay of ATP extracted from Escherichia coli cells added to cow milk.

  18. A mouse model of mitochondrial complex III dysfunction induced by myxothiazol

    Energy Technology Data Exchange (ETDEWEB)

    Davoudi, Mina [Pediatrics, Department of Clinical Sciences, Lund, Lund University, Lund 22185 (Sweden); Kallijärvi, Jukka; Marjavaara, Sanna [Folkhälsan Research Center, Biomedicum Helsinki, University of Helsinki, 00014 (Finland); Kotarsky, Heike; Hansson, Eva [Pediatrics, Department of Clinical Sciences, Lund, Lund University, Lund 22185 (Sweden); Levéen, Per [Pediatrics, Department of Clinical Sciences, Lund, Lund University, Lund 22185 (Sweden); Folkhälsan Research Center, Biomedicum Helsinki, University of Helsinki, 00014 (Finland); Fellman, Vineta, E-mail: Vineta.Fellman@med.lu.se [Pediatrics, Department of Clinical Sciences, Lund, Lund University, Lund 22185 (Sweden); Folkhälsan Research Center, Biomedicum Helsinki, University of Helsinki, 00014 (Finland); Children’s Hospital, Helsinki University Hospital, University of Helsinki, Helsinki 00029 (Finland)

    2014-04-18

    Highlights: • Reversible chemical inhibition of complex III in wild type mouse. • Myxothiazol causes decreased complex III activity in mouse liver. • The model is useful for therapeutic trials to improve mitochondrial function. - Abstract: Myxothiazol is a respiratory chain complex III (CIII) inhibitor that binds to the ubiquinol oxidation site Qo of CIII. It blocks electron transfer from ubiquinol to cytochrome b and thus inhibits CIII activity. It has been utilized as a tool in studies of respiratory chain function in in vitro and cell culture models. We developed a mouse model of biochemically induced and reversible CIII inhibition using myxothiazol. We administered myxothiazol intraperitoneally at a dose of 0.56 mg/kg to C57Bl/J6 mice every 24 h and assessed CIII activity, histology, lipid content, supercomplex formation, and gene expression in the livers of the mice. A reversible CIII activity decrease to 50% of control value occurred at 2 h post-injection. At 74 h only minor histological changes in the liver were found, supercomplex formation was preserved and no significant changes in the expression of genes indicating hepatotoxicity or inflammation were found. Thus, myxothiazol-induced CIII inhibition can be induced in mice for four days in a row without overt hepatotoxicity or lethality. This model could be utilized in further studies of respiratory chain function and pharmacological approaches to mitochondrial hepatopathies.

  19. Trivalent europium speciation in a room-temperature ionic liquid

    International Nuclear Information System (INIS)

    Mekki, S.

    2006-10-01

    microscopic scale. The manuscript 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 2 N for the whole thesis and start with the electrochemical study. In the second chapter, we present the study of europium solvation in the ionic liquid media. In the third part, we expose the results concerning TTA solvation and its complexation with europium in bumimTf 2 N under different conditions. Finally in the last chapter, we present the results obtained for the europium extraction in a three-stage extraction system: water/bumimTf 2 N/supercritical CO 2 . This work highlights the potential use of ionic liquids and particularly bumimTf 2 N in the spent nuclear fuel reprocessing. The ability to extract quantitatively a trivalent lanthanide has been demonstrated. This fundamental study can be regarded as a feasibility demonstration to build an ionic liquid-containing extraction system, in the aim of possible large-scale application. (author)

  20. Temperature effects in the valence fluctuation of europium intermetallic compounds

    International Nuclear Information System (INIS)

    Menezes, O.L.T. de; Troper, A.; Gomes, A.A.

    1978-03-01

    A previously reported model for valence fluctuations in europium compound in order to account for thermal occupation effect. Experimental results are critically discussed and new experiments are suggested

  1. Complexation of f elements by tripodal ligands containing aromatic nitrogens. Application to the selective extraction of actinides(III)

    International Nuclear Information System (INIS)

    Wietzke, Raphael

    1999-01-01

    This work initiates a research project, whose aim is the actinides(lll)/lanthanides(III) separation by liquid-liquid extraction. We were interested in the study of the coordination chemistry of lanthanides(III) and uranium(III) (uranium(III) as model for the actinides(III)), with the aim to show differences between the two families and to better understand the coordination properties involved in the extraction process. We studied the lanthanide(III) and uranium(III) complexation with tripodal ligands containing aromatic nitrogens. Several tripodal ligands were synthesized varying the type and the number of the donor atoms. The lanthanide(III) complexes have been characterized in the solid state and in solution (by several techniques: "1H NMR, ESMS, luminescence, UV spectrophotometry, conductometry). Differences in the coordination were found depending on the nature of the donor atoms. The new ligands, tris(2-pyrazinylmethyl)amine (tpza) et tris(N,N-diethyl-2-carbamoyl-6- pyridylmethyl)amine (tpaa), have shown a selectivity for the actinides(III) with promising results in liquid-liquid extraction. The comparison between the lanthanum(III) and uranium(III) complexes with the ligand tpza showed differences in the bonding nature, which could be attributed to a covalent contribution to the metal-ligand bond. (author) [fr

  2. Stability constants of some Y(III)-complexes from potentiometric data

    Energy Technology Data Exchange (ETDEWEB)

    Pande, S P; Munshi, K N [Nagpur Univ. (India). Dept. of Chemistry

    1975-06-01

    Potentiometric studies have been carried out on the metal complexes of yttrium(III) with 5-sulphosalicylic acid 3,5-dinitro salicylic acid sodium 2,3-dihydroxynaphthalene-6-sulfonate, and nitroso-R-salt. The Calvin-Bjerrum pH-titration technique, as used by Iriving and Rossotti, has been applied to determine the stepwise protonation constants of the ligands and the formation constants of the complexes. The log K values have been computed by alternative methods, at three different temperatures at an ionic strength of 0.2M(NaClO/sub 4/).(author).

  3. Experimental and Computational Evidence for the Mechanism of Intradiol Catechol Dioxygenation by Non-Heme Iron(III) Complexes

    Science.gov (United States)

    Jastrzebski, Robin; Quesne, Matthew G; Weckhuysen, Bert M; de Visser, Sam P; Bruijnincx, Pieter C A

    2014-01-01

    Catechol intradiol dioxygenation is a unique reaction catalyzed by iron-dependent enzymes and non-heme iron(III) complexes. The mechanism by which these systems activate dioxygen in this important metabolic process remains controversial. Using a combination of kinetic measurements and computational modelling of multiple iron(III) catecholato complexes, we have elucidated the catechol cleavage mechanism and show that oxygen binds the iron center by partial dissociation of the substrate from the iron complex. The iron(III) superoxide complex that is formed subsequently attacks the carbon atom of the substrate by a rate-determining C=O bond formation step. PMID:25322920

  4. On the composition of nonstoichiometric europium monoxide

    International Nuclear Information System (INIS)

    Ignat'eva, N.I.

    1990-01-01

    Consideration is given to results of of investigation into chemical composition, homogeneity region, type of disordering of nonstoichiometric europium monoxide. Precision methods of X-ray diffraction, electron-microscopic, atomic-absorption chemical analysis were used. It is shown that lattice volume reduces with increase of oxygen content in the oxide. For monocrystal of EuO 1.01 composition a=5.146 A. All samples of europium monoxide are characterized by low conductivity. Conductivity value changes by two orders (from 10 -8 to 10 -6 Θ -1 ·cm -1 ) when passing from the sample of stoichiometric composition to maximally disordered one. The disordering is considered according to the type of charged cation vacancies, leading to occurrence of equivalent number of electron defects of positive holes. 4 refs.; 1 tab

  5. APW research of europium monochalcogenides. 1

    International Nuclear Information System (INIS)

    Farberovich, O.V.; Vlasov, S.V.

    1981-01-01

    The augmented plane wave method (APW) is used for a theoretical study of the electron properties of europium monochalcogenides. Spin-polarized energy band calculations of the ferromagnetic EuO, EuS, and EuSe explain qualitatively the exchange interactions therein. Based on the APW data in the frame of perturbation theory the Coulomb electron-electron interaction at the 4f shell of europium is taken into account for EuO and EuS. The band structures and the multiplet terms of the f 6 d and 3d 9 4f 8 excited states gives a new interpretation of a known experimental spectra for these compounds. (author)

  6. Cytotoxic property of surfactant-cobalt(III) complexes on a human breast cancer cell line.

    Science.gov (United States)

    Kumar, Rajendran Senthil; Riyasdeen, Anvarbatcha; Dinesh, Mohanakrishnan; Paul, Christo Preethy; Srinag, Suresh; Krishnamurthy, Hanumanthappa; Arunachalam, Sankaralingam; Akbarsha, Mohammad Abdulkadher

    2011-07-01

    The cancer chemotherapeutic potential of surfactant-cobalt(III) complexes, cis-[Co(bpy)(2)(C(14)H(29)NH(2))Cl](ClO(4))(2)·3 H(2)O (1) and cis-[Co(phen)(2)(C(14)H(29)NH(2))Cl](ClO(4))(2)·3 H(2)O (2) (bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline) on MCF-7 breast cancer cell was determined adopting MTT assay and specific staining techniques. The complexes affected the viability of the cells significantly and the cells succumbed to apoptosis as seen in the changes in the nuclear morphology and cytoplasmic features. Since the complex 2 appeared to be more potent, further assays were carried out on the complex 2. Single-cell electrophoresis indicated DNA damage. The translocation of phosphatidyl serine and loss of mitochondrial potential was revealed by annexin V-Cy3 staining and JC-1 staining respectively. Western blot analysis revealed up-regulation of pro-apoptotic p53 and down-regulation of anti-apoptotic Bcl-2 protein. Taken together, the surfactant-cobalt(III) complex 2 would be a potential candidate for further investigation for application as a chemotherapeutic for cancers in general and estrogen receptor-positive breast cancer in particular. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Functionalized cyclopentadienyl rhodium(III) bipyridine complexes: synthesis, characterization, and catalytic application in hydrogenation of ketones.

    Science.gov (United States)

    Wang, Wan-Hui; Suna, Yuki; Himeda, Yuichiro; Muckerman, James T; Fujita, Etsuko

    2013-07-14

    A series of highly functionalized cyclopentadienyl rhodium(III) complexes, [Cp'Rh(bpy)Br](ClO4) (Cp' = substituted cyclopentadienyl), was synthesized from various multi-substituted cyclopentadienes (Cp'H). [Rh(cod)Cl]2 and Cp'H were firstly converted to [Cp'Rh(cod)] complexes, which were then treated with Br2 to give the rhodium(III) dibromides [Cp'RhBr2]2. The novel complexes [Cp'Rh(bpy)Br](ClO4) were obtained readily by the reaction of 2,2'-bipyridine with [Cp'RhBr2]2. These rhodium complexes [Cp'Rh(bpy)Br](ClO4) were fully characterized and utilized in the hydrogenation of cyclohexanone and acetophenone with generally high yields, but they did not exhibit the same reactivity trends for the two substrate ketones. The different activity of these complexes for the different substrates may be due to the influence of the substituents on the Cp' rings.

  8. Alkali metal cation complexation and solvent interactions by robust chromium(III) fluoride complexes

    DEFF Research Database (Denmark)

    Birk, T.; Magnussen, M.J.; Piligkos, Stergios

    2010-01-01

    )] have been synthesized from mer-[CrF3(py)(3)] and shown to precipitate sodium salts from solution, of which 3[CrF3(Me(3-)tacn)]center dot 2Na(Bph(4)).solv and 6[CrF3(terpy)]center dot 4Na(Bph(4)).solv have been crystallographically characterized. In these clusters, the neutral fluoride complexes bring...

  9. Ferromagnetic dinuclear mixed-valence Mn(II)/Mn(III) complexes: building blocks for the higher nuclearity complexes. structure, magnetic properties, and density functional theory calculations.

    Science.gov (United States)

    Hänninen, Mikko M; Välivaara, Juha; Mota, Antonio J; Colacio, Enrique; Lloret, Francesc; Sillanpää, Reijo

    2013-02-18

    A series of six mixed-valence Mn(II)/Mn(III) dinuclear complexes were synthesized and characterized by X-ray diffraction. The reactivity of the complexes was surveyed, and structures of three additional trinuclear mixed-valence Mn(III)/Mn(II)/Mn(III) species were resolved. The magnetic properties of the complexes were studied in detail both experimentally and theoretically. All dinuclear complexes show ferromagnetic intramolecular interactions, which were justified on the basis of the electronic structures of the Mn(II) and Mn(III) ions. The large Mn(II)-O-Mn(III) bond angle and small distortion of the Mn(II) cation from the ideal square pyramidal geometry were shown to enhance the ferromagnetic interactions since these geometrical conditions seem to favor the orthogonal arrangement of the magnetic orbitals.

  10. Study of the selectivity of poly-nitrogenous extracting molecules in the complexation of actinides (III) and lanthanides (III) in solution in anhydrous pyridine

    International Nuclear Information System (INIS)

    Riviere, Ch.

    2000-01-01

    The aim of this work is to better understand the factors which contribute to the separation of lanthanides(III) and actinides(III). Polydentate nitrogenous molecules present an interesting selectivity. A thermodynamic study of the complexation in pyridine of lanthanide and uranium by the bipyridine ligand (bipy) has been carried out. The formation constants and the thermodynamic values of the different complexes have been determined. It has been shown that the bipy complexes formation is controlled by the enthalpy and unfavored by the entropy. The conductometry has revealed too a significant difference in the uranium and lanthanides complexation by the bipyridine ligand. The use of the phenanthroline ligand induces a better complexation of the metallic ions but the selectivity is not improved. On the other hand, the decrease of the basicity and the increase of the ligand denticity (for instance in the case of the use of ter-pyridine) favour the selectivity without improving the complexation. The selectivity difference for the complexation of actinides(III) and lanthanides(III) by the different studied ligands (independent systems) has been confirmed by experiments of inter-metals competition. (O.M.)

  11. Grafting of a novel gold(III) complex on nanoporous MCM-41 and evaluation of its toxicity in Saccharomyces cerevisiae.

    Science.gov (United States)

    Fazaeli, Yousef; Amini, Mostafa M; Ashourion, Hamed; Heydari, Homayoun; Majdabadi, Abbas; Jalilian, Amir Reza; Abolmaali, Shamsozoha

    2011-01-01

    The goal of this research was to investigate the potential of newly synthesized gold complex trichloro(2,4,6-trimethylpyridine)Au(III) as an anticancer agent. The gold(III) complex was synthesized and grafted on nanoporous silica, MCM-41, to produce AuCl(3)@PF-MCM- 41 (AuCl(3) grafted on pyridine-functionalized MCM-41). The toxicity of trichloro(2,4,6- trimethylpyridine)Au(III) and AuCl(3)@PF-MCM-41 in Saccharomyces cerevisiae (as a model system) was studied. The gold(III) complex showed a mid cytotoxic effect on yeast viability. Using the drug delivery system, nanoporous MCM-41, the gold(III) complex became a strong inhibitor for growth of yeast cells at a very low concentration. Furthermore, the animal tests revealed a high uptake of AuCl(3)@PF-MCM-41 in tumor cells. The stability of the compound was confirmed in human serum.

  12. Uranium(iii) complexes supported by hydrobis(mercaptoimidazolyl)borates: synthesis and oxidation chemistry.

    Science.gov (United States)

    Maria, Leonor; Santos, Isabel C; Santos, Isabel

    2018-05-23

    The reaction of [UI3(thf)4] with the sodium or lithium salts of hydrobis(2-mercapto-1-methylimidazolyl)borate ligands ([H(R)B(timMe)2]-) in a 1 : 2 ratio, in tetrahydrofuran, gave the U(iii) complexes [UI{κ3-H,S,S'-H(R)B(timMe)2}2(thf)2] (R = H (1), Ph (2)) in good yields. Crystals of [UI{κ3-H,S,S'-H(Ph)B(timMe)2}2(thf)2] (2) were obtained by recrystallization from a tetrahydrofuran/acetonitrile solution, and the ion-separated uranium complex [U{κ3-H,S,S'-H(Ph)B(timMe)2}2(CH3CN)3][I] (3-I) was obtained by dissolution of 2 in acetonitrile followed by recrystallization. One-electron oxidation of 2 with AgBPh4 or I2 resulted in the formation of the cationic U(iv) complexes [U{κ3-H,S,S'-H(Ph)B(timMe)2}3][X] (X = BPh4 (6-BPh4), I (6-I)), due to a ligand redistribution process. These complexes are the first examples of homoleptic poly(azolyl)borate U(iv) complexes. Treatment of complex 2 with azobenzene led to the isolation of crystals of the U(iv) compound [UI{κ3-H(Ph)B(timMe)2}2(κ2-timMe)] (7). Treatment of 2 with pyridine-N oxide (pyNO) led to the formation of the uranyl complex [UO2{κ2-S,S'-H(Ph)B(timMe)2}2] (8) and of complex 6-I, while from the reaction of [U{κ3-H(Ph)B(timMe)2}2(thf)3][BPh4] (5) with pyNO, the oxo-bridged U(iv) complex [{U{κ3-H(Ph)B(timMe)2}2(pyNO)}2(μ-O)][BPh4]2 (9) was also obtained. In the U(iii) and U(iv) complexes, the bis(azolyl)borate ligands bind to the uranium center in a κ3-H,S,S' coordination mode, while in the U(vi) complex the ligands bind to the metal in a κ2-S,S' mode. The presence of UH-B interactions in the solid-state, for the nine-coordinate complexes 1, 2, 3, 6 and 7 and for the eight-coordinate complex 9, was supported by IR spectroscopy and/or X-ray diffraction analysis.

  13. Enhanced fluorescence of Tb(III), Dy(III) perchlorate by salicylic acid in bis(benzoylmethyl) sulfoxide complexes and luminescence mechanism

    International Nuclear Information System (INIS)

    Li Wenxian; Zheng Yushan; Sun Xiaojun; Chai Wenjuan; Ren Tie; Shi Xiaoyan

    2010-01-01

    Two novel ternary rare earth perchlorate complexes had been synthesized by using bis(benzoylmethyl) sulfoxide as first ligand (L=C 6 H 5 COCH 2 SOCH 2 COC 6 H 5 ), salicylic acid as second ligand (L ' =C 6 H 4 OHCOO - ). The compounds were characterized by elemental analysis, TG-DSC and molar conductivities in DMF solution. The composition was suggested as [REL 5 L'](ClO 4 ) 2 .nH 2 O (RE=Tb, Dy; n=6, 8 ). Based on IR, 1 HNMR and UV spectra, it showed that the first ligand, bis(benzoylmethyl) sulfoxide (L), bonded with Tb(III), Dy(III) ions by the oxygen atom of sulfinyl group. The second ligand, salicylic acid group (L'), not only bonded with RE(III) ions by one oxygen atom of carboxyl group but also bonded with RE(III) ions by oxygen atom of phenolic hydroxyl group. In bis(benzoylmethyl) sulfoxide system, fluorescent spectra of the complexes showed that the luminescence of Tb(III), Dy(III) ions was enhanced by the second ligand salicylic acid. The ternary complexes had stronger fluorescence than the binary ones where only bis(benzoylmethyl) sulfoxide acted as ligand. Phosphorescent spectra of the two ligands indicated that the coordination of salicylic acid resulted in the matching extent increasing between the triplet state of ligand and excited state of the rare earths. The relationship between fluorescence lifetime and fluorescence intensity was also discussed.

  14. Preparation of EuSe nanoparticles from Eu(III) complex containing selenides

    International Nuclear Information System (INIS)

    Adachi, Taka-aki; Tanaka, Atsushi; Hasegawa, Yasuchika; Kawai, Tsuyoshi

    2008-01-01

    The EuSe nanoparticles were prepared by the thermal reduction of Europium nitrate with new organic selenium compound, tetraphenylphosphonium diphenylphosphinediselenide (PPh 4 )(Se 2 P(C 6 H 5 ) 2 ), for the first time. EuSe nanoparticles were identified by the X-ray diffraction (XRD), the transmission electron microscope (TEM) and the energy dispersive X-ray spectroscopy (EDX) measurements. The average size of the EuSe nanoparticles was found to be 19 nm. The energy gap in EuSe nanoparticles of 19 nm was estimated by edge of absorption band, giving the energy gap of 1.86 eV

  15. Combined Respiratory Chain Deficiency and UQCC2 Mutations in Neonatal Encephalomyopathy: Defective Supercomplex Assembly in Complex III Deficiencies

    Directory of Open Access Journals (Sweden)

    René G. Feichtinger

    2017-01-01

    Full Text Available Vertebrate respiratory chain complex III consists of eleven subunits. Mutations in five subunits either mitochondrial (MT-CYB or nuclear (CYC1, UQCRC2, UQCRB, and UQCRQ encoded have been reported. Defects in five further factors for assembly (TTC19, UQCC2, and UQCC3 or iron-sulphur cluster loading (BCS1L and LYRM7 cause complex III deficiency. Here, we report a second patient with UQCC2 deficiency. This girl was born prematurely; pregnancy was complicated by intrauterine growth retardation and oligohydramnios. She presented with respiratory distress syndrome, developed epileptic seizures progressing to status epilepticus, and died at day 33. She had profound lactic acidosis and elevated urinary pyruvate. Exome sequencing revealed two homozygous missense variants in UQCC2, leading to a severe reduction of UQCC2 protein. Deficiency of complexes I and III was found enzymatically and on the protein level. A review of the literature on genetically distinct complex III defects revealed that, except TTC19 deficiency, the biochemical pattern was very often a combined respiratory chain deficiency. Besides complex III, typically, complex I was decreased, in some cases complex IV. In accordance with previous observations, the presence of assembled complex III is required for the stability or assembly of complexes I and IV, which might be related to respirasome/supercomplex formation.

  16. Synthesis, Characterization, DNA Interaction, and Antitumor Activities of La (III) Complex with Schiff Base Ligand Derived from Kaempferol and Diethylenetriamine.

    Science.gov (United States)

    Wang, Qin; Huang, Yu; Zhang, Jin-Sheng; Yang, Xin-Bin

    2014-01-01

    A novel La (III) complex, [LaL(H2O)3]NO3 ·3H2O, with Schiff base ligand L derived from kaempferol and diethylenetriamine, has been synthesized and characterized by elemental analysis, IR, UV-visible, (1)H NMR, thermogravimetric analysis, and molar conductance measurements. The fluorescence spectra, circular dichroism spectra, and viscosity measurements and gel electrophoresis experiments indicated that the ligand L and La (III) complex could bind to CT-DNA presumably via intercalative mode and the La (III) complex showed a stronger ability to bind and cleave DNA than the ligand L alone. The binding constants (K b ) were evaluated from fluorescence data and the values ranged from 0.454 to 0.659 × 10(5) L mol(-1) and 1.71 to 17.3 × 10(5) L mol(-1) for the ligand L and La (III) complex, respectively, in the temperature range of 298-310 K. It was also found that the fluorescence quenching mechanism of EB-DNA by ligand L and La (III) complex was a static quenching process. In comparison to free ligand L, La (III) complex exhibited enhanced cytotoxic activities against tested tumor cell lines HL-60 and HepG-2, which may correlate with the enhanced DNA binding and cleaving abilities of the La (III) complex.

  17. Selective Sensing of Tyrosine Phosphorylation in Peptides Using Terbium(III Complexes

    Directory of Open Access Journals (Sweden)

    Jun Sumaoka

    2016-01-01

    Full Text Available Phosphorylation of tyrosine residues in proteins, as well as their dephosphorylation, is closely related to various diseases. However, this phosphorylation is usually accompanied by more abundant phosphorylation of serine and threonine residues in the proteins and covers only 0.05% of the total phosphorylation. Accordingly, highly selective detection of phosphorylated tyrosine in proteins is an urgent subject. In this review, recent developments in this field are described. Monomeric and binuclear TbIII complexes, which emit notable luminescence only in the presence of phosphotyrosine (pTyr, have been developed. There, the benzene ring of pTyr functions as an antenna and transfers its photoexcitation energy to the TbIII ion as the emission center. Even in the coexistence of phosphoserine (pSer and phosphothreonine (pThr, pTyr can be efficintly detected with high selectivity. Simply by adding these TbIII complexes to the solutions, phosphorylation of tyrosine in peptides by protein tyrosine kinases and dephosphorylation by protein tyrosine phosphatases can be successfully visualized in a real-time fashion. Furthermore, the activities of various inhibitors on these enzymes are quantitatively evaluated, indicating a strong potential of the method for efficient screening of eminent inhibitors from a number of candidates.

  18. Lutetium(III) aqua ion: On the dynamical structure of the heaviest lanthanoid hydration complex

    Energy Technology Data Exchange (ETDEWEB)

    Sessa, Francesco; D’Angelo, Paola, E-mail: p.dangelo@uniroma1.it [Dipartimento di Chimica, Università di Roma “La Sapienza,” P. le A. Moro 5, 00185 Roma (Italy); Spezia, Riccardo [CNRS, UMR 8587, Laboratoire Analyse et Modelisation Pour la Biologie et l’Environnement, Université d’Evry Val d’Essonne, Blvd. F. Mitterrand, 91025 Evry Cedex (France)

    2016-05-28

    The structure and dynamics of the lutetium(III) ion in aqueous solution have been investigated by means of a polarizable force field molecular dynamics (MD). An 8-fold square antiprism (SAP) geometry has been found to be the dominant configuration of the lutetium(III) aqua ion. Nevertheless, a low percentage of 9-fold complexes arranged in a tricapped trigonal prism (TTP) geometry has been also detected. Dynamic properties have been explored by carrying out six independent MD simulations for each of four different temperatures: 277 K, 298 K, 423 K, 632 K. The mean residence time of water molecules in the first hydration shell at room temperature has been found to increase as compared to the central elements of the lanthanoid series in agreement with previous experimental findings. Water exchange kinetic rate constants at each temperature and activation parameters of the process have been determined from the MD simulations. The obtained structural and dynamical results suggest that the water exchange process for the lutetium(III) aqua ion proceeds with an associative mechanism, in which the SAP hydration complex undergoes temporary structural changes passing through a 9-fold TTP intermediate. Such results are consistent with the water exchange mechanism proposed for heavy lanthanoid atoms.

  19. Luminescence and circularly polarized luminescence of macrocyclic Eu(III) and Tb(III) complexes embedded in xerogel and sol-gel SiO2 glasses

    International Nuclear Information System (INIS)

    Morita, M.; Rau, D.; Kai, T.

    2002-01-01

    Luminescence, time-resolved luminescence, circularly polarized luminescence (CPL) and decay profiles of Ln(III)(15-crownether-5) (Ln=Ce, Sm, Eu, Tb) and Tb(III)-(R),(S)-cyclen derivative complexes doped in xerogel and sol-gel silica glasses are measured at temperatures down to 10 K to characterize luminescence properties and the electronic structure in the excited states. Luminescence spectral profiles and calculation of crystal field parameters (B 0 (2) ,B 2 (2) ) in the 5 D 0 → 7 F J (J=1,2) transition give evidence of the fact that the pentagonal and planar structure of Eu(III) (15-crownether-5) does hold in xerogel and sol-gel glasses prepared at temperatures below 100 deg. C. As annealing temperatures are increased from 80 deg. C to 750 deg. C, Eu(III) complexes in sol-gel glasses are found to decompose gradually to SiO 2 :Eu 3+ . Tb(III)-(R) and (S)-cyclen derivative complexes in xerogel reveal at room temperature and 10 K sharp CPL spectra with luminescence dissymmetry factors g lum =-0.1 and 0.1, respectively. These complexes doped in sol-gel glasses represent luminescence characteristics of rare earth ions encapsulated in the nano-porous host

  20. Synthesis, structures and urease inhibitory activity of cobalt(III) complexes with Schiff bases.

    Science.gov (United States)

    Jing, Changling; Wang, Cunfang; Yan, Kai; Zhao, Kedong; Sheng, Guihua; Qu, Dan; Niu, Fang; Zhu, Hailiang; You, Zhonglu

    2016-01-15

    A series of new cobalt(III) complexes were prepared. They are [CoL(1)(py)3]·NO3 (1), [CoL(2)(bipy)(N3)]·CH3OH (2), [CoL(3)(HL(3))(N3)]·NO3 (3), and [CoL(4)(MeOH)(N3)] (4), where L(1), L(2), L(3) and L(4) are the deprotonated form of N'-(2-hydroxy-5-methoxybenzylidene)-3-methylbenzohydrazide, N'-(2-hydroxybenzylidene)-3-hydroxylbenzohydrazide, 2-[(2-dimethylaminoethylimino)methyl]-4-methylphenol, and N,N'-bis(5-methylsalicylidene)-o-phenylenediamine, respectively, py is pyridine, and bipy is 2,2'-bipyridine. The complexes were characterized by infrared and UV-Vis spectra, and single crystal X-ray diffraction. The Co atoms in the complexes are in octahedral coordination. Complexes 1 and 4 show effective urease inhibitory activities, with IC50 values of 4.27 and 0.35 μmol L(-1), respectively. Complex 2 has medium activity against urease, with IC50 value of 68.7 μmol L(-1). While complex 3 has no activity against urease. Molecular docking study of the complexes with Helicobacter pylori urease was performed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Spectroscopic and thermodynamic study of the complexation of Cm(III) and Eu(III) with hydrophilic bis-triazinyl pyridines

    International Nuclear Information System (INIS)

    Ruff, Christian

    2013-01-01

    In the present work the complexation of Cm(III) and Eu(III) with a hydrophilic 2,6-bis-(1,2,4-triazinyl)-pyridine (aq-BTP) is studied. Aq-BTP complexes actinides(III) selectively over lanthanides(III) in nitric acid solution. The object of this work is the identification and the spectroscopic and thermodynamic characterization of the Cm(III) and Eu(III) complex species present in solution. The results should contribute to a better fundamental understanding of the driving force behind BTPs selectivity towards trivalent actinides on a molecular level. Time-resolved laser fluorescence spectroscopy (TRLFS), luminescence and UV/Vis spectroscopy are applied. Information on the structure of M(III)-aq-BTP complex species is obtained from density functional theory. Three different M(III) complex species containing one, two or three aq-BTP ligands are identified in H 2 O at pH 3.0. Relative fluorescence intensity factors are determined for each of the [M(aq-BTP) n ] complexes (M = Cm(III)/Eu(III), n = 1 - 3). These factors are required to quantify the complexes. The stability constant logβ 3 of the [Cm(aq-BTP) 3 ] complex (which is the one relevant to extraction processes) is two orders of magnitude higher than that of the corresponding Eu(III) complex. This difference is in agreement with the separation factor (SF Am(III)/Eu(III) = 150) determined experimentally by liquid-liquid extraction. The difference in the stability constants originates from the different reaction enthalpies for the formation of the [M(aq-BTP) 3 ] complexes. These results represent the thermodynamic driving force for the aq-BTPs selectivity towards trivalent actinides over lanthanides. Comparing the stability constants of the [M(aq-BTP) n ] species (M = Cm(III)/Eu(III), n = 1 - 3) shows an increasing selectivity with increasing number of coordinated aq-BTP ligands. Hence, high selectivity is achieved if the f-element ions are fully coordinated by nine N-donor atoms (three aq-BTP ligands). A less

  2. Spectrophotometric study of the complexation equilibria of lanthanum(III) with 1,4-bis(4'-methylanilino)anthraquinone and the determination of lanthanum(III)

    International Nuclear Information System (INIS)

    Idriss, K.A.-R; El-Shahawy, A.S.; Sedaira, H.; Harfoush, A.A.

    1985-01-01

    The complexation equilibria of lanthanum(III) with 1,4-bis(4'-methylanilino)anthraquinone (Quinizarin Green) were studied spectrophotometrically in 40% V/V dimethylformamide using graphical analysis of the absorbance curves. The reaction mechanism of lanthanum with the bisarylaminoanthraquinone dye within the pH range 6 to 9.25 was demonstrated. The thermodynamic stabilities and the molar absorptivities of the complexes formed were determined. The optimum conditions for the spectrophotometric determination of La(III) with this reagent were found. (author)

  3. Arene activation by a nonheme iron(III)-hydroperoxo complex: pathways leading to phenol and ketone products.

    Science.gov (United States)

    Faponle, Abayomi S; Banse, Frédéric; de Visser, Sam P

    2016-07-01

    Iron(III)-hydroperoxo complexes are found in various nonheme iron enzymes as catalytic cycle intermediates; however, little is known on their catalytic properties. The recent work of Banse and co-workers on a biomimetic nonheme iron(III)-hydroperoxo complex provided evidence of its involvement in reactivity with arenes. This contrasts the behavior of heme iron(III)-hydroperoxo complexes that are known to be sluggish oxidants. To gain insight into the reaction mechanism of the biomimetic iron(III)-hydroperoxo complex with arenes, we performed a computational (density functional theory) study. The calculations show that iron(III)-hydroperoxo reacts with substrates via low free energies of activation that should be accessible at room temperature. Moreover, a dominant ketone reaction product is observed as primary products rather than the thermodynamically more stable phenols. These product distributions are analyzed and the calculations show that charge interaction between the iron(III)-hydroxo group and the substrate in the intermediate state pushes the transferring proton to the meta-carbon atom of the substrate and guides the selectivity of ketone formation. These studies show that the relative ratio of ketone versus phenol as primary products can be affected by external interactions of the oxidant with the substrate. Moreover, iron(III)-hydroperoxo complexes are shown to selectively give ketone products, whereas iron(IV)-oxo complexes will react with arenes to form phenols instead.

  4. Orthodontic clockwise rotation of maxillomandibular complex for improving facial profile in late teenagers with Class III malocclusion: A preliminary report

    OpenAIRE

    Eric JW Liou; Yu-Chi Wang

    2018-01-01

    Objective: Orthodontic camouflage treatments improve occlusion but might worsen facial profile in patients with Class III malocclusion. It has been reported that surgical clockwise rotation of maxillomandibular complex (MMc) improves facial profile by reducing chin prominence and chin throat length in patients with Class III malocclusion. The purpose of this report was to illustrate two orthodontic techniques for clockwise rotation of the MMc in late teenagers with Class III malocclusion and ...

  5. Synthesis, Characterization and Antibacterial Studies of N-(Benzothiazol-2-yl)-4-chlorobenzenesulphonamide and Its Neodymium(III) and Thallium(III) Complexes.

    Science.gov (United States)

    Obasi, Lawrence Nnamdi; Oruma, Uchechukwu Susan; Al-Swaidan, Ibrahim Abdulrazak; Ramasami, Ponnadurai; Ezeorah, Chigozie Julius; Ochonogor, Alfred Ezinna

    2017-02-22

    N -(Benzothiazol-2-yl)-4-chlorobenzenesulphonamide (NBTCS) was synthesized by condensation reaction of 4-chlorobenzenesulphonyl chloride and 2-aminobenzothiazole in acetone under reflux. Neodymium(III) and thallium(III) complexes of the ligand were also synthesized. Both ligand and metal complexes were characterized using UV-Vis, IR, ¹H- and 13 C-NMR spectroscopies, elemental analysis and molar conductance measurement. IR studies revealed that the ligand is tridentate and coordinates to the metal ions through nitrogen and oxygen atoms of the sulphonamide group and nitrogen atom attached to benzothiazole ring. The neodymium(III) complex displays a coordination number of eight while thallium(III) complex displays a coordination number of six. The ligand and its complexes were screened in vitro for their antibacterial activities against Escherichia coli strains ( E. coli 6 and E. coli 13 ), Proteus species, Staphylococcus aureus and Pseudomonas aeruginosa using the agar well diffusion technique. The synthesized compounds were found to be more active against the microorganisms screened relative to ciprofloxacin, gentamicin and co-trimoxazole.

  6. Synthesis, Characterization and Antibacterial Studies of N-(Benzothiazol-2-yl-4-chlorobenzenesulphonamide and Its Neodymium(III and Thallium(III Complexes

    Directory of Open Access Journals (Sweden)

    Lawrence Nnamdi Obasi

    2017-02-01

    Full Text Available N-(Benzothiazol-2-yl-4-chlorobenzenesulphonamide (NBTCS was synthesized by condensation reaction of 4-chlorobenzenesulphonyl chloride and 2-aminobenzothiazole in acetone under reflux. Neodymium(III and thallium(III complexes of the ligand were also synthesized. Both ligand and metal complexes were characterized using UV-Vis, IR, 1H- and 13C-NMR spectroscopies, elemental analysis and molar conductance measurement. IR studies revealed that the ligand is tridentate and coordinates to the metal ions through nitrogen and oxygen atoms of the sulphonamide group and nitrogen atom attached to benzothiazole ring. The neodymium(III complex displays a coordination number of eight while thallium(III complex displays a coordination number of six. The ligand and its complexes were screened in vitro for their antibacterial activities against Escherichia coli strains (E. coli 6 and E. coli 13, Proteus species, Staphylococcus aureus and Pseudomonas aeruginosa using the agar well diffusion technique. The synthesized compounds were found to be more active against the microorganisms screened relative to ciprofloxacin, gentamicin and co-trimoxazole.

  7. Technetium cyanide chemistry: synthesis and characterization of technetium(III) and -(V) cyanide complexes

    International Nuclear Information System (INIS)

    Trop, H.S.; Jones, A.G.; Davison, A.

    1980-01-01

    Several new technetium cyanide complexes have been prepared and characterized. The reaction of ammonium hexaiodotechnetate(IV) with potassium cyanide in refluxing aqueous methanol under nitrogen yields potassium heptacyanotechnetate(III) dihydrate, K 4 Tc(CN) 7 .2H 2 O (1). Infrared and Raman measurements indicate that 1 has a pentagonal bipyramidal structure (D/sub 5h/) in both solid and solution. Aqueous solutions of 1 are air sensitive, decomposing to potassium oxopentacyanotechnetate(V) tetrahydrate, K 2 TcO(CN) 5 .4H 2 O (2). This species can also be prepared from the reaction of TcO 2 .xH 2 O with hot aqueous potassium cyanide solutions. Hydrolysis of 2 in water yields potassium trans-dioxo-tetracyanotechnetate(V), K 3 TcO 2 (CN) 4 (3). Preparation of 3 can also be achieved from the treatment of [TcO 2 (Py) 4 ]ClO 4 .2H 2 O with aqueous potassium cyanide. Infrared and Raman measurements on 3 are consistent with the proposed trans-dioxo (D/sub 4h/) structure. Reaction of the oxotetrachlorotechnetate(V) anion, TcOCl 4 , with potassium cyanide in methanol produces trans-oxomethoxytetracyanotechnetate(V). [TcO(OMe)(CN) 4 ] (4). The full details of the synthesis and characterization of these interesting technetium(III) and -(V) complexes, as well as observations on the infrared and Raman spectra of trans-dioxo metal complexes and the hydrolysis of species 2, are presented

  8. A type III-B CRISPR-Cas effector complex mediating massive target DNA destruction.

    Science.gov (United States)

    Han, Wenyuan; Li, Yingjun; Deng, Ling; Feng, Mingxia; Peng, Wenfang; Hallstrøm, Søren; Zhang, Jing; Peng, Nan; Liang, Yun Xiang; White, Malcolm F; She, Qunxin

    2017-02-28

    The CRISPR (clustered regularly interspaced short palindromic repeats) system protects archaea and bacteria by eliminating nucleic acid invaders in a crRNA-guided manner. The Sulfolobus islandicus type III-B Cmr-α system targets invading nucleic acid at both RNA and DNA levels and DNA targeting relies on the directional transcription of the protospacer in vivo. To gain further insight into the involved mechanism, we purified a native effector complex of III-B Cmr-α from S. islandicus and characterized it in vitro. Cmr-α cleaved RNAs complementary to crRNA present in the complex and its ssDNA destruction activity was activated by target RNA. The ssDNA cleavage required mismatches between the 5΄-tag of crRNA and the 3΄-flanking region of target RNA. An invader plasmid assay showed that mutation either in the histidine-aspartate acid (HD) domain (a quadruple mutation) or in the GGDD motif of the Cmr-2α protein resulted in attenuation of the DNA interference in vivo. However, double mutation of the HD motif only abolished the DNase activity in vitro. Furthermore, the activated Cmr-α binary complex functioned as a highly active DNase to destroy a large excess DNA substrate, which could provide a powerful means to rapidly degrade replicating viral DNA. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  9. Luminescent chiral ionic Ir(III) complexes: Synthesis and photophysical properties

    Energy Technology Data Exchange (ETDEWEB)

    Ricciardi, Loredana, E-mail: loredana.ricciardi@unical.it [CNR NANOTEC-Istituto di Nanotecnologia U.O.S. Cosenza, 87036 Arcavacata di Rende (CS) (Italy); La Deda, Massimo; Ionescu, Andreea; Godbert, Nicolas; Aiello, Iolinda; Ghedini, Mauro [MAT-INLAB (Laboratorio di Materiali Molecolari Inorganici), LASCAMM and CR INSTM, Unità INSTM della Calabria, Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, 87036 Arcavacata di Rende (CS) (Italy); Fusè, Marco, E-mail: marco.fuse@unimi.it [Dipartimento di Scienze Farmaceutiche, Università di Milano, Via Golgi 19, 20133 Milano (Italy); Rimoldi, Isabella; Cesarotti, Edoardo [Dipartimento di Scienze Farmaceutiche, Università di Milano, Via Golgi 19, 20133 Milano (Italy)

    2016-02-15

    Three homologous series of luminescent octahedral ionic Ir(III) complexes (1–12) with a dual stereogenic center of general formula {sup Δ,Λ} {sup (R,S)}[(ppy){sub 2}Ir(R-campy)]X, where ppy=2-phenylpyridine, R-campy=2-methyl-5,6,7,8-tetrahydroquinolin-8-amine (Me-campy) or 8-amino-5,6,7,8-tetrahydroquinolines (H-campy) and as counterions X{sup −}=Cl{sup −} or CH{sub 3}COO{sup −} have been synthesized and characterized. The NMR characterization of each complex highlighted the diastereoisomeric purity and the absolute configuration has been confirmed by Electronic Circular Dichroism spectroscopy. The absorption and the luminescence properties of the compounds in solution and in solid state have been investigated by UV–vis, steady-state emission and time-correlated single-photon counting spectroscopy. The obtained results from the 12 compounds highlight the difficult to correlate photophysical properties in solution to the stereochemistry, while excited states decay studies of the solid state samples indicate a correlation between photophysics and packing mode which is affected by the different stereochemistry. - Highlights: • Luminescent chiral ionic Ir(III) complexes have been synthesized and characterized. • Presence in the same structure of two stereogenic centers. • Use of camphorsulfonate as resolving anion to obtain enantiomerically pure samples. • Stereoisomers produce aggregates with different emitting properties. • Lifetimes from solid samples show the presence of AIPE.

  10. Synthesis, characterization, DNA binding and catalytic applications of Ru(III) complexes.

    Science.gov (United States)

    Shoair, A F; El-Shobaky, A R; Azab, E A

    2015-01-01

    A new series of azodye ligands 5-chloro-3-hydroxy-4-(aryldiazenyl)pyridin-2(1H)-one (HLn) were synthesized by coupling of 5-chloro-3-hydroxypyridin-2(1H)-one with aniline and its p-derivatives. These ligands and their Ru(III) complexes of the type trans-[Ru(Ln)2(AsPh3)2]Cl were characterized by elemental analyses, IR, (1)H NMR and UV-Visible spectra as well as magnetic and thermal measurements. The molar conductance measurements proved that all the complexes are electrolytes. IR spectra show that the ligands (HLn) acts as a monobasic bidentate ligand by coordinating via the nitrogen atom of the azo group (NN) and oxygen atom of the deprotonated phenolic OH group, thereby forming a six-membered chelating ring and concomitant formation of an intramolecular hydrogen bond. The molecular and electronic structures of the investigated compounds (HLn) were also studied using quantum chemical calculations. The calf thymus DNA binding activity of the ligands (HLn) and their Ru(III) complexes were studied by absorption spectra and viscosity measurements. The mechanism and the catalytic oxidation of benzyl alcohol by trans-[Ru(Ln)2(AsPh3)2]Cl with hydrogen peroxide as co-oxidant were described. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. EXAFS studies on the reaction of gold (III) chloride complex ions with sodium hydroxide and glucose.

    Science.gov (United States)

    Pacławski, K; Zajac, D A; Borowiec, M; Kapusta, Cz; Fitzner, K

    2010-11-11

    EXAFS and QEXAFS experiments were carried out at Hasylab laboratory in DESY center (X1 beamline, Hamburg, Germany) to monitor the course of the hydrolysis reactions of [AuCl(4)](-) complex ions as well as their reduction using glucose. As a result, changes in the spectra of [AuCl(4)](-) ions and disappearance of absorption Au-L(3) edge were registered. From the results of the experiments we have carried out, the changes in bond lengths between Au(3+) central ion and Cl(-) ligands as well as the reduction of Au(3+) to metallic form (colloidal gold was formed in the system) are evident. Good quality spectra obtained before and after the reactions gave a chance to determine the bond length characteristic of Au-Cl, Au-OH and Au-Au pairs. Additionally, the obtained results were compared with the simulated spectra of different gold (III) complex ions, possibly present in the solution. Finally, the mechanism of these reactions was suggested. Unfortunately, it was not possible to detect the changes in the structure of gold (III) complex ions within the time of reaction, because of too high rates of both processes (hydrolysis and reduction) as compared with the detection time.

  12. Aspartic acid complexation of Am(III) and U(VI)

    International Nuclear Information System (INIS)

    Saito, A.; Choppin, G.R.

    1984-01-01

    Stability constants of Am(III) and U(VI) with L-aspartic acid have been determined at pH 8.00 by means of the solvent extraction technique. It was found that Am(III) forms 1:1 and 1:2 complexes while U(VI) formed only the 1:1 complex under these conditions. The stability constants were: Am +3 : I = 0.10 M; log β 1 = 4.81 +- 0.03, log β 2 = 6.75 +- 0.03 I = 0.70 M; log β 1 = 4.53 +- 0.08 log β 2 = 6.65 +- 0.06 UO +2 2 : I = 0.70 M; log β 1 = 3.32 +- 0.04. Comparison of these stability constants with corresponding values of some dicarboxylate ligands suggests that at pH 8 the binding of Am +3 and UO +2 2 involves both carboxylates. In the Am-aspartate complex, the data indicate the possibility of weak interaction between the Am +3 and the amino group. (orig.)

  13. Intramolecular deactivation processes of electronically excited Lanthanide(III) complexes with organic acids of low molecular weight

    Science.gov (United States)

    Burek, Katja; Eidner, Sascha; Kuke, Stefanie; Kumke, Michael U.

    2018-02-01

    The luminescence of Lanthanide(III) complexes with different model ligands was studied under direct as well as sensitized excitation conditions. The research was performed in the context of studies dealing with deep-underground storages for high-level nuclear waste. Here, Lanthanide(III) ions served as natural analogues for Actinide(III) ions and the low-molecular weight organic ligands are present in clay minerals and furthermore, they were employed as proxies for building blocks of humic substances, which are important complexing molecules in the natural environment, e.g., in the far field of a repository site. Time-resolved luminescence spectroscopy was applied for a detailed characterization of Eu(III), Tb(III), Sm(III) and Dy(III) complexes in aqueous solutions. Based on the observed luminescence the ligands were tentatively divided into two groups (A, B). The luminescence of Lanthanide(III) complexes of group A was mainly influenced by an energy transfer to OH-vibrations. Lanthanide(III) complexes of group B showed ligand-related luminescence quenching, which was further investigated. To gain more information on the underlying quenching processes of group A and B ligands, measurements at different temperatures (77 K ≤ T ≤ 353 K) were performed and activation energies were determined based on an Arrhenius analysis. Moreover, the influence of the ionic strength between 0 M ≤ I ≤ 4 M on the Lanthanide(III) luminescence was monitored for different complexes, in order to evaluate the influence of specific conditions encountered in host rocks foreseen as potential repository sites.

  14. Structure and luminescent property of complexes of aryl carboxylic acid-functionalized polystyrene with Eu(III) and Tb(III) ions.

    Science.gov (United States)

    Gao, Baojiao; Shi, Nan; Qiao, Zongwen

    2015-11-05

    Via polymer reactions, naphthoic acid (NA) and benzoic acid (BA) were bonded onto the side chains of polystyrene (PS), respectively, and two aryl carboxylic acid-functionalized polystyrenes, PSNA and PSBA, were obtained. Using PSNA and PSBA as macromolecule ligands and Eu(3+) and Tb(3+) ions as central ions, various luminescent binary polymer-rare earth complexes were prepared. At the same time, with 1,10-phenanthroline (Phen) and 4,4'-bipyridine (Bipy) as small-molecule co-ligands, various ternary polymer-rare earth complexes were also prepared. On the basis of characterizing PSNA, PSBA and complexes, the relationship between structure and luminescent property for these prepared complexes were mainly investigated. The study results show that the macromolecule ligands PSNA and PSBA, or the bonded NA and BA ligands, can strongly sensitize the fluorescence emissions of Eu(3+) ion or Tb(3+) ion, but the sensitization effect is strongly dependent on the structure of the ligands and the property of the central ions, namely it is strongly dependent on the matching degree of energy levels. The fluorescence emission of the binary complex PS-(NA)3-Eu(III) is stronger than that PS-(BA)3-Eu(III), indicating ligand NA has stronger sensitization action for Eu(3+) ion than ligand BA; the binary complex PS-(BA)3-Tb(III) emit strong characteristic fluorescence of Tb(3+) ion, displaying that ligand BA can strongly sensitize Tb(3+) ion, whereas the binary complex PS-(NA)3-Tb(III) nearly does not emit the characteristic fluorescence of Tb(3+) ion, showing that ligand NA does not sensitize Tb(3+) ion. The fluorescence intensity of the ternary complexes is much stronger than that of the binary complexes in the same series. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. A new ion imprinted polymer based on Ru(III)-thiobarbituric acid complex for solid phase extraction of ruthenium(III) prior to its determination by ETAAS

    International Nuclear Information System (INIS)

    Zambrzycka, Elżbieta; Godlewska-Żyłkiewicz, Beata

    2014-01-01

    A new ruthenium ion imprinted polymer was prepared from the Ru(III) 2-thiobarbituric acid complex (the template), methacrylic acid or acrylamide (the functional monomers), and ethylene glycol dimethacrylate (the cross-linking agent) using 2,2′-azobisisobutyronitrile as the radical initiator. The ion imprinted polymer was characterized and used as a selective sorbent for the solid phase extraction of Ru(III) ions. The effects of type of functional monomer, sample volume, solution pH and flow rate on the extraction efficiency were studied in the dynamic mode. Ru(III) ion was quantitatively retained on the sorbents in the pH range from 3.5 to 10, and can be eluted with 4 mol L−1 aqueous ammonia. The affinity of Ru(III) for the ion imprinted polymer based on the acrylamide monomer is weaker than that for the polymer based on the methacrylic acid monomer, which therefore was used in interference studies and in analytical applications. Following extraction of Ru(III) ions with the imprint and their subsequent elution from the polymer with aqueous ammonia, Ru(III) was detected by electrothermal atomic absorption spectrometry with a detection limit of 0.21 ng mL −1 . The method was successfully applied to the determination of trace amounts of Ru(III) in water, waste, road dust and platinum ore (CRM SARM 76) with a reproducibility (expressed as RSD) below 6.4 %. (author)

  16. Magneto and spectral behaviour of lanthanide(III) perchlorate complexes of n-isonicotinamidoanisalaldimine

    International Nuclear Information System (INIS)

    Agarwal, R.K.; Agarwal, Himanshu; Sarin, R.K.

    1996-01-01

    A new series of lanthanide(III) perchlorate complexes of N-isonicotinamidoanisalaldimine (INH-SAL) with the general composition (Ln(INH-SAL) 4 )(ClO) 4 ) 3 (Ln=La, Pr, Nd, Sm, Gd, Tb or Dy) were synthesized and characterized by elemental analyses, conductance, molecular weight, infrared and electronic spectral data. INH-SAL acts as a bidentate (N, O) chelating agents. The tentative coordination number eight has been assigned. Thermal behaviour of some representative chelates has also been investigated. (author). 14 refs., 2 tabs

  17. Fe(III) mobilisation by carbonate in low temperature environments: Study of the solubility of ferrihydrite in carbonate media and the formation of Fe(III) carbonate complexes

    International Nuclear Information System (INIS)

    Grivé, Mireia; Duro, Lara; Bruno, Jordi

    2014-01-01

    Graphical abstract: - Highlights: • We have determined thermodynamic stabilities of Fe(III)-carbonate species. • We have determined the effect of those species on the solubility of ferrihydrite. • Results. • Highlight the importance of two Fe(III)-carbonate: FeOHCO 3 and Fe(CO 3 ) 3 3− . - Abstract: The linkage between the iron and the carbon cycles is of paramount importance to understand and quantify the effect of increased CO 2 concentrations in natural waters on the mobility of iron and associated trace elements. In this context, we have quantified the thermodynamic stability of mixed Fe(III) hydroxo-carbonate complexes and their effect on the solubility of Fe(III) oxihydroxides. We present the results of carefully performed solubility measurements of 2-line ferrihydrite in the slightly acidic to neutral–alkaline pH ranges (3.8–8.7) under constant pCO 2 varying between (0.982–98.154 kPa) at 25 °C. The outcome of the work indicates the predominance of two Fe(III) hydroxo carbonate complexes FeOHCO 3 and Fe(CO 3 ) 3 3− , with formation constants log * β° 1,1,1 = 10.76 ± 0.38 and log β° 1,0,3 = 24.24 ± 0.42, respectively. The solubility constant for the ferrihydrite used in this study was determined in acid conditions (pH: 1.8–3.2) in the absence of CO 2 and at T = (25 ± 1) °C, as log * K s,0 = 1.19 ± 0.41. The relative stability of the Fe(III)-carbonate complexes in alkaline pH conditions has implications for the solubility of Fe(III) in CO 2 -rich environments and the subsequent mobilisation of associated trace metals that will be explored in subsequent papers

  18. Technetium electrochemistry. 7. Electrochemical and spectroelectrochemical studies on technetium(III) and -(II) complexes containing polypyridyl ligands

    International Nuclear Information System (INIS)

    Wilcox, B.E.; Deutsch, E.

    1991-01-01

    The redox properties of a series of technetium(III/II) complexes of the general formula cis(X), trans(P)-[Tc III/II X 2 (PR w R') 2 L] 10+ , where X = Cl or Br, PR 2 R' = dimethylphenylphosphine or ethyldiphenylphosphine, and L = 2,2'-bipyridine (bpy), 4,4'-dimethyl-2,2'-bipyridine (Me 2 bpy), or 1,10-phenanthroline (phen), were investigated in 0.1 M TEAP/acetonitrile by cyclic voltammetry at a platinum-disk electrode. These complexes exhibit diffusion-controlled, 1-equiv Tc(IV)/Tc(III) redox couples and also Tc(III)/Tc(II) redox couples. Spectropotentiostatic experiments on three complexes of this class in 0.5 M TEAP/DMF confirm the 1-equiv character of the Tc(III)/Tc(II) couple. The electrochemical behavior of Tc(II) complexes of the general formula trans(P)-[TcX(PR 2 R') 2 terpy] + , terpy = 2,2':6',2 double-prime-terpyridine, was also investigated under the same conditions as above. These complexes exhibit diffusion-controlled, 1-equiv Tc(III)/Tc(II) redox couples and Tc(II)/Tc(I) redox couples. Spectropotentiostatic experiments on trans(P)-[TcCl(PMe 2 Ph) 2 terpy] + confirm the 1-equiv character of the Tc(III)/Tc(II) couple but show that the Tc(II)/Tc(I) couple is not reversible on the spectropotentiostatic time scale

  19. Synthesis of novel fluorescent probe Tb(III)-7-carboxymethoxy-4-methylcoumarin complex for sensing of DNA

    International Nuclear Information System (INIS)

    Hussein, Belal H.M.; Azab, Hassan A.; Fathalla, Walid; Ali, Sherin A.M.

    2013-01-01

    New fluorescent probe Tb(III) (7-carboxymethoxy-4-methylcoumarin)2(SCN) (C2H5OH)(H2O) was synthesized and characterized by spectroscopy and thermal analysis. The absorption and fluorescence spectra of 7-carboxymethoxy-4-methylcoumarin (CMMC) and Tb(III)–CMMC complex have been measured in different solvents. The interactions of Tb(III)–CMMC complex with calf thymus nucleic acid (CT-DNA) have been investigated using steady state fluorescence measurements. The changes in the fluorescence intensity have been used for the quantitative determination of DNA with LOD of 3.45 ng in methanol–water (9:1, v/v). The association constants of DNA with Tb(III)–CMMC complex was found to be 2.62×1010 M −1 . - Highlights: ► New fluorescent probe Terbium (III)-7-carboxy methoxy-4-methylcoumarin complex has been synthesized and characterized. ► FTIR spectrum of Tb(III)-complex shows a characteristic band for thiocyanate group. ► DNA interaction with Terbium (III)-7-carboxy methoxy-4-methylcoumarin has been studied by fluorescence techniques. ► The change in the fluorescence intensity has been used for the quantitative determination of DNA. ► The result was better than most of the well-known methods including the ethidium bromide method.

  20. Synthesis of novel fluorescent probe Tb(III)-7-carboxymethoxy-4-methylcoumarin complex for sensing of DNA

    Energy Technology Data Exchange (ETDEWEB)

    Hussein, Belal H.M., E-mail: belalhussein102@yahoo.com [Department of Chemistry, Faculty of Science, Suez Canal University, Ismailia (Egypt); Azab, Hassan A. [Department of Chemistry, Faculty of Science, Suez Canal University, Ismailia (Egypt); Fathalla, Walid [Department of Mathematical and Physical Sciences, Faculty of Engineering, Port-Said University, Port-Said (Egypt); Ali, Sherin A.M. [Department of Mathematical and Physical Sciences, Faculty of Engineering, Suez Canal University, Ismailia (Egypt)

    2013-02-15

    New fluorescent probe Tb(III) (7-carboxymethoxy-4-methylcoumarin)2(SCN) (C2H5OH)(H2O) was synthesized and characterized by spectroscopy and thermal analysis. The absorption and fluorescence spectra of 7-carboxymethoxy-4-methylcoumarin (CMMC) and Tb(III)-CMMC complex have been measured in different solvents. The interactions of Tb(III)-CMMC complex with calf thymus nucleic acid (CT-DNA) have been investigated using steady state fluorescence measurements. The changes in the fluorescence intensity have been used for the quantitative determination of DNA with LOD of 3.45 ng in methanol-water (9:1, v/v). The association constants of DNA with Tb(III)-CMMC complex was found to be 2.62 Multiplication-Sign 1010 M{sup -1}. - Highlights: Black-Right-Pointing-Pointer New fluorescent probe Terbium (III)-7-carboxy methoxy-4-methylcoumarin complex has been synthesized and characterized. Black-Right-Pointing-Pointer FTIR spectrum of Tb(III)-complex shows a characteristic band for thiocyanate group. Black-Right-Pointing-Pointer DNA interaction with Terbium (III)-7-carboxy methoxy-4-methylcoumarin has been studied by fluorescence techniques. Black-Right-Pointing-Pointer The change in the fluorescence intensity has been used for the quantitative determination of DNA. Black-Right-Pointing-Pointer The result was better than most of the well-known methods including the ethidium bromide method.

  1. 2-(2′-Pyridyl)-4,6-diphenylphosphinine versus 2-(2′-Pyridyl)-4,6-diphenylpyridine: Synthesis, Characterization, and Reactivity of Cationic RhIII and IrIII Complexes Based on Aromatic Phosphorus Heterocycles

    NARCIS (Netherlands)

    de Krom, I.; Broeckx, L.E.E.; Lutz, M.; Müller, Christian

    2013-01-01

    The bidentate P,N hybrid ligand 1 allows access for the first time to novel cationic phosphinine-based RhIII and IrIII complexes, broadening significantly the scope of low-coordinate aromatic phosphorus heterocycles for potential applications. The coordination chemistry of 1 towards RhIII and IrIII

  2. Quantitative description and local structures of trivalent metal ions Eu(III) and Cm(III) complexed with poly-acrylic acid

    International Nuclear Information System (INIS)

    Montavon, G.; Huclier-Markai, S.; Grambow, B.; Bouby, M.; Geckeis, H.; Rabung, T.; Huclier-Markai, S.; Pashalidis, I.; Amekraz, B.; Moulin, C.

    2008-01-01

    The trivalent metal ion (M(III) = Cm, Eu)/poly-acrylic acid (PAA) system was studied in the pH range between 3 and 5.5 for a molar PAA-to-metal ratio above 1. The interaction was studied for a wide range of PAA (0.05 mg L -1 -50 g L -1 ) and metal ion concentrations (2*10 -9 - 10 -3 M). This work aimed at 3 goals (i) to determine the stoichiometry of M(III)-PAA complexes, (ii) to determine the number of complexed species and the local environment of the metal ion, and (iii) to quantify the reaction processes. Asymmetric flow-field-flow fractionation (AsFIFFF) coupled to ICP-MS evidenced that size distributions of Eu-PAA complexes and PAA were identical, suggesting that Eu bound to only one PAA chain. Time-resolved laser fluorescence spectroscopy (TRLFS) measurements performed with Eu and Cm showed a continuous shift of the spectra with increasing pH. The environment of complexed metal ions obviously changes with pH. Most probably, spectral variations arose from conformational changes within the M(Ill)-PAA complex due to pH variation. Complexation data describing the distribution of complexed and free metal ion were measured with Cm by TRLFS. They could be quantitatively described in the whole pH-range studied by considering the existence of only a single complexed species. This indicates that the slight changes in M(III) speciation with pH observed at the molecular level do not significantly affect the intrinsic binding constant. The interaction constant obtained from the modelling must be considered as a mean interaction constant. (authors)

  3. The Effect of Pressure and Temperature on Separation of Free Gadolinium(III) From Gd-DTPA Complex by Nanofiltration-Complexation Method

    Science.gov (United States)

    Rahayu, Iman; Anggraeni, Anni; Ukun, MSS; Bahti, Husein H.

    2017-05-01

    Nowdays, the utilization of rare earth elements has been carried out widely in industry and medicine, one of them is gadolinium in Gd-DTPA complex is used as a contrast agent in a magnetic resonance imaging (MRI) diagnostic to increase the visual contrast between normal tissue and diseased. Although the stability of a given complex may be high enough, the complexation step couldnot have been completed, so there is possible to gadolinium(III) in the complex compound. Therefore, the function of that compounds should be dangerous because of the toxicity of gadolinium(III) in human body. So, it is necessarry to separate free gadolinium(III) from Gd-DTPA complex by nanofiltration-complexation. The method of this study is complexing of Gd2O3 with DTPA ligand by reflux and separation of Gd-DTPA complex from gadolinium(III) with a nanofiltration membrane on the variation of pressures(2, 3, 4, 5, 6 bars) and temperature (25, 30, 35, 40 °C) and determined the flux and rejection. The results of this study are the higher of pressures and temperatures, permeation flux are increasing and ion rejections are decreasing and gave the free gadolinium(III) rejection until 86.26%.

  4. Platinum(II)-gadolinium(III) complexes as potential single-molecular theranostic agents for cancer treatment.

    Science.gov (United States)

    Zhu, Zhenzhu; Wang, Xiaoyong; Li, Tuanjie; Aime, Silvio; Sadler, Peter J; Guo, Zijian

    2014-11-24

    Theranostic agents are emerging multifunctional molecules capable of simultaneous therapy and diagnosis of diseases. We found that platinum(II)-gadolinium(III) complexes with the formula [{Pt(NH3)2Cl}2GdL](NO3)2 possess such properties. The Gd center is stable in solution and the cytoplasm, whereas the Pt centers undergo ligand substitution in cancer cells. The Pt units interact with DNA and significantly promote the cellular uptake of Gd complexes. The cytotoxicity of the Pt-Gd complexes is comparable to that of cisplatin at high concentrations (≥0.1 mM), and their proton relaxivity is higher than that of the commercial magnetic resonance imaging (MRI) contrast agent Gd-DTPA. T1-weighted MRI on B6 mice demonstrated that these complexes can reveal the accumulation of platinum drugs in vivo. Their cytotoxicity and imaging capabilities make the Pt-Gd complexes promising theranostic agents for cancer treatment. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Neutral, seven-coordinate dioxime complexes of technetium(III): Synthesis and characterization

    International Nuclear Information System (INIS)

    Linder, K.E.; Malley, M.F.; Gougoutas, J.Z.; Unger, S.E.; Nunn, A.D.

    1990-01-01

    The tin-capped complexes 99 Tc(oxime) 3 (μ-OH)SnCl 3 [oxime = dimethylglyoxime (DMG) or cyclohexanedione dioxime (CDO)] can be prepared by the reduction of NH 4 TcO 4 with 2 equiv of SnCl 2 in the presence of dioxime and HCl. These tin-capped complexes can be readily converted into a new class of uncapped Tc-dioxime compounds, TcCl(oxime) 3 , by treatment with HCl. This reaction is reversible. Both the tin-capped and uncapped tris(dioxime) complexes can be converted to the previously reported boron-capped Tc-dioxime complexes TcCl(oxime) 3 BR (R = alkyl, OH) by reaction with boronic acids or with boric acid at low pH. All of these complexes [Tc(oxime) 3 (μ-OH)SnCl 3 , TcCl(oxime) 3 , and TcCl(oxime) 3 BR] appear to be neutral, seven-coordinate compounds of technetium(III). They have been characterized by elemental analysis, 1 H NMR and UV/visible spectroscopy, conductivity, and fast atom bombardment mass spectrometry. The synthesis, characterization, and reactivity of these compounds is discussed. The x-ray crystal structure analysis of TcCl(DMG) 3 and an abbreviated structure report on TcCl(DMG) 3 MeB are described. Crystal data for TcCl(DMG) 3 are reported. 23 refs., 6 figs., 5 tabs

  6. Synthesis, structure and photoluminescence of novel lanthanide (Tb(III), Gd(III)) complexes with 6-diphenylamine carbonyl 2-pyridine carboxylate

    International Nuclear Information System (INIS)

    An Baoli; Gong Menglian; Cheah, Kok-Wai; Wong, Wai-Kwok; Zhang Jiming

    2004-01-01

    A novel organic ligand, 6-diphenylamine carbonyl 2-pyridine carboxylic acid (HDPAP), and the corresponding lanthanide complexes, tris(6-diphenylamine carbonyl 2-pyridine carboxylato) terbium(III) (Tb-DPAP) and tris(6-diphenylamine carbonyl 2-pyridine carboxylato) gadolinium(III) (Gd-DPAP) have been designed and synthesized. The crystal structure and photoluminescence of Tb-DPAP and Gd-DPAP have been studied. The results showed that the lanthanide complexes have electroneutral structures, and the solid terbium complex emits characteristic green fluorescence of Tb(III) ions at room temperature while the gadolinium complex emits the DPAP ligand phosphorescence. The lowest triplet level of DPAP ligand was calculated from the phosphorescence spectrum of Gd-DPAP in N,N-dimethyl formamide (DMF) dilute solution determined at 77 K, and the energy transfer mechanisms in the lanthanide complexes were discussed. The lifetimes of the 5 D 4 levels of Tb 3+ ions in the terbium complex were examined using time-resolved spectroscopy, and the values are 0.0153±0.0001 ms for solid Tb(DPAP) 3 ·11.5H 2 O and 0.074±0.007 ms for 2.5x10 -5 mol/l Tb-DPAP ethanol solution

  7. Complexation of Eu(III) with a polymeric cement additive as a potential carrier of actinides

    Energy Technology Data Exchange (ETDEWEB)

    Lippold, Holger; Becker, Michael [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Reactive Transport

    2017-06-01

    In the long term, cementitious materials in a final repository will be exposed to leaching processes generating highly alkaline solutions. Polymeric additives, so-called superplasticizers, are considered as potential mobilizing agents for released radionuclides, since it is uncertain whether complete degradation will take place under the evolving aqueous conditions. Regarding the complexing properties of superplasticizers, there are only indirect assessments so far. In this study, first systematic investigations on complexation with Eu(III) as an analogue of trivalent actinides were performed at variable pH and electrolyte content (NaCl, CaCl{sub 2}) using ultrafiltration as a separation method. A stability constant was derived according to the charge neutralization model. For this purpose, the proton exchange capacity was determined by potentiometric titration.

  8. Theoretical studies of boron(III) complexes for the new blue luminescent material

    International Nuclear Information System (INIS)

    Lee, Jung Eun; Choi, Gyu Chul; Rim, Byung O.; Kim, Sung Min; Park, No Gill; Ha, Yun Kyoung; Kim, Young Sik

    2004-01-01

    Boron(III) complexes, BPh 2 (2-py-aza) and Bph 2 (2-py-in), are known as blue emitting materials. In this paper, we have studied various ligand effects of boron complex on the absorption (UV) and electroluminescence (EL) peaks computationally. To obtain optical properties, TD-DFT(B3LYP) methods are used with 6-31+G(d) basis set. It was found that EL peaks of those materials are calculated at 454 and 510 nm, which are considerably consistent with experimental data. From the results, we newly proposed two materials, BPh 2 (PBI-Me) and BPh 2 (PBI-Ph), as blue luminescent materials, whose calculated EL peaks are at 456 and 480 nm, respectively. Through the calculation results, newly designed compounds showed possibility as efficient and promising emitters in EL device

  9. Bacterial flagella and Type III secretion: case studies in the evolution of complexity.

    Science.gov (United States)

    Pallen, M J; Gophna, U

    2007-01-01

    Bacterial flagella at first sight appear uniquely sophisticated in structure, so much so that they have even been considered 'irreducibly complex' by the intelligent design movement. However, a more detailed analysis reveals that these remarkable pieces of molecular machinery are the product of processes that are fully compatible with Darwinian evolution. In this chapter we present evidence for such processes, based on a review of experimental studies, molecular phylogeny and microbial genomics. Several processes have played important roles in flagellar evolution: self-assembly of simple repeating subunits, gene duplication with subsequent divergence, recruitment of elements from other systems ('molecular bricolage'), and recombination. We also discuss additional tentative new assignments of homology (FliG with MgtE, FliO with YscJ). In conclusion, rather than providing evidence of intelligent design, flagellar and non-flagellar Type III secretion systems instead provide excellent case studies in the evolution of complex systems from simpler components.

  10. Complex networks for data-driven medicine: the case of Class III dentoskeletal disharmony

    International Nuclear Information System (INIS)

    Scala, A; Auconi, P; Scazzocchio, M; Caldarelli, G; McNamara, JA; Franchi, L

    2014-01-01

    In the last decade, the availability of innovative algorithms derived from complexity theory has inspired the development of highly detailed models in various fields, including physics, biology, ecology, economy, and medicine. Due to the availability of novel and ever more sophisticated diagnostic procedures, all biomedical disciplines face the problem of using the increasing amount of information concerning each patient to improve diagnosis and prevention. In particular, in the discipline of orthodontics the current diagnostic approach based on clinical and radiographic data is problematic due to the complexity of craniofacial features and to the numerous interacting co-dependent skeletal and dentoalveolar components. In this study, we demonstrate the capability of computational methods such as network analysis and module detection to extract organizing principles in 70 patients with excessive mandibular skeletal protrusion with underbite, a condition known in orthodontics as Class III malocclusion. Our results could possibly constitute a template framework for organising the increasing amount of medical data available for patients’ diagnosis. (paper)

  11. Differences and Comparisons of the Properties and Reactivities of Iron(III)–hydroperoxo Complexes with Saturated Coordination Sphere

    Science.gov (United States)

    Faponle, Abayomi S; Quesne, Matthew G; Sastri, Chivukula V; Banse, Frédéric; de Visser, Sam P

    2015-01-01

    Heme and nonheme monoxygenases and dioxygenases catalyze important oxygen atom transfer reactions to substrates in the body. It is now well established that the cytochrome P450 enzymes react through the formation of a high-valent iron(IV)–oxo heme cation radical. Its precursor in the catalytic cycle, the iron(III)–hydroperoxo complex, was tested for catalytic activity and found to be a sluggish oxidant of hydroxylation, epoxidation and sulfoxidation reactions. In a recent twist of events, evidence has emerged of several nonheme iron(III)–hydroperoxo complexes that appear to react with substrates via oxygen atom transfer processes. Although it was not clear from these studies whether the iron(III)–hydroperoxo reacted directly with substrates or that an initial O–O bond cleavage preceded the reaction. Clearly, the catalytic activity of heme and nonheme iron(III)–hydroperoxo complexes is substantially different, but the origins of this are still poorly understood and warrant a detailed analysis. In this work, an extensive computational analysis of aromatic hydroxylation by biomimetic nonheme and heme iron systems is presented, starting from an iron(III)–hydroperoxo complex with pentadentate ligand system (L52). Direct C–O bond formation by an iron(III)–hydroperoxo complex is investigated, as well as the initial heterolytic and homolytic bond cleavage of the hydroperoxo group. The calculations show that [(L52)FeIII(OOH)]2+ should be able to initiate an aromatic hydroxylation process, although a low-energy homolytic cleavage pathway is only slightly higher in energy. A detailed valence bond and thermochemical analysis rationalizes the differences in chemical reactivity of heme and nonheme iron(III)–hydroperoxo and show that the main reason for this particular nonheme complex to be reactive comes from the fact that they homolytically split the O–O bond, whereas a heterolytic O–O bond breaking in heme iron(III)–hydroperoxo is found. PMID:25399782

  12. High-level inhibition of mitochondrial complexes III and IV is required to increase glutamate release from the nerve terminal

    Directory of Open Access Journals (Sweden)

    Kilbride Seán M

    2011-07-01

    Full Text Available Abstract Background The activities of mitochondrial complex III (ubiquinol-cytochrome c reductase, EC 1.10.2.2 and complex IV (cytochrome c oxidase EC 1.9.3.1 are reduced by 30-70% in Huntington's disease and Alzheimer's disease, respectively, and are associated with excitotoxic cell death in these disorders. In this study, we investigated the control that complexes III and complex IV exert on glutamate release from the isolated nerve terminal. Results Inhibition of complex III activity by 60-90% was necessary for a major increase in the rate of Ca2+-independent glutamate release to occur from isolated nerve terminals (synaptosomes depolarized with 4-aminopyridine or KCl. Similarly, an 85-90% inhibition of complex IV activity was required before a major increase in the rate of Ca2+-independent glutamate release from depolarized synaptosomes was observed. Inhibition of complex III and IV activities by ~ 60% and above was required before rates of glutamate efflux from polarized synaptosomes were increased. Conclusions These results suggest that nerve terminal mitochondria possess high reserves of complex III and IV activity and that high inhibition thresholds must be reached before excess glutamate is released from the nerve terminal. The implications of the results in the context of the relationship between electron transport chain enzyme deficiencies and excitotoxicity in neurodegenerative disorders are discussed.

  13. High-level inhibition of mitochondrial complexes III and IV is required to increase glutamate release from the nerve terminal

    LENUS (Irish Health Repository)

    Kilbride, Sean M

    2011-07-26

    Abstract Background The activities of mitochondrial complex III (ubiquinol-cytochrome c reductase, EC 1.10.2.2) and complex IV (cytochrome c oxidase EC 1.9.3.1) are reduced by 30-70% in Huntington\\'s disease and Alzheimer\\'s disease, respectively, and are associated with excitotoxic cell death in these disorders. In this study, we investigated the control that complexes III and complex IV exert on glutamate release from the isolated nerve terminal. Results Inhibition of complex III activity by 60-90% was necessary for a major increase in the rate of Ca2+-independent glutamate release to occur from isolated nerve terminals (synaptosomes) depolarized with 4-aminopyridine or KCl. Similarly, an 85-90% inhibition of complex IV activity was required before a major increase in the rate of Ca2+-independent glutamate release from depolarized synaptosomes was observed. Inhibition of complex III and IV activities by ~ 60% and above was required before rates of glutamate efflux from polarized synaptosomes were increased. Conclusions These results suggest that nerve terminal mitochondria possess high reserves of complex III and IV activity and that high inhibition thresholds must be reached before excess glutamate is released from the nerve terminal. The implications of the results in the context of the relationship between electron transport chain enzyme deficiencies and excitotoxicity in neurodegenerative disorders are discussed.

  14. Half-Lantern Pt(II and Pt(III Complexes. New Cyclometalated Platinum Derivatives

    Directory of Open Access Journals (Sweden)

    Violeta Sicilia

    2014-08-01

    Full Text Available The divalent complex [{Pt(bzq(μ-L}2] (1 [Hbzq = benzo[h]quinolone, HL = CF3C4H2N2SH: 4-(trifluoromethylpyrimidine-2-thiol] was obtained from equimolar amounts of [Pt(bzq(NCMe2]ClO4 and 4-(trifluoromethylpyrimidine-2-thiol with an excess of NEt3. The presence of a low intensity absorption band at 486 nm (CH2Cl2, assignable to a metal-metal-to-ligand charge transfer transition (1MMLCT [dσ*(Pt2→π*(bzq], is indicative of the existence of two platinum centers located in close proximity because the rigidity of the half-lantern structure allows the preservation of these interactions in solution. Compound 1 undergoes two-electron oxidation upon treatment with halogens X2 (X2: Cl2, Br2 or I2 to give the corresponding dihalodiplatinum (III complexes [{Pt(bzq(μ-LX}2] (L = CF3C4H2N2S-κN,S; X: Cl 2, Br 3, I 4. Complexes 2–4 were also obtained by reaction of 1 with HX (molar ratio 1:2, 10% excess of HX in THF with yields of about 80% and compound 2 was also obtained by reaction of [{Pt(bzq(μ-Cl}2] with HL (4-(trifluoromethylpyrimidine-2-thiol in molar ratio 1:2 in THF, although in small yield. The X-ray structures of 2 and 3 confirmed the half-lantern structure and the anti configuration of the molecules. Both of them show Pt–Pt distances (2.61188(15 Å 2, 2.61767(16 Å 3 in the low range of those observed in Pt2(III,IIIX2 half-lantern complexes.

  15. Complex compounds of terbium(III) with some nonsteroidal anti-inflammatory drugs and their analytical applications

    International Nuclear Information System (INIS)

    Teslyuk, O.I.; Egorova, A.V.; Yagodkin, B.N.; Bel'tyukova, S.V.

    2007-01-01

    Luminescence properties of the complexes of terbium(III) with nonsteroidal anti-inflammatory drugs (ibuprofen and orthofen) were studied. It was demonstrated that in the presence of organic bases (2,2'-dipyridyl and 1,10-phenanthroline) mixed-ligand complexes are formed and the luminescence intensity of terbium(III) increases by a factor of up to 250. The optimum complexation conditions were determined. It was proposed to use these complexes as analytical forms for the luminescence determination of nonsteroidal anti-inflammatory drugs (ibuprofen and orthofen) in pharmaceutical dosage forms. The detection limits are 2 and 0.05 μg/ml, respectively [ru

  16. Immobilization of selenium by biofilm of Shewanella putrefaciens with and without Fe(III)-citrate complex

    International Nuclear Information System (INIS)

    Suzuki, Yoshinori; Sakama, Yosuke; Saiki, Hiroshi; Kitamura, Akira; Yoshikawa, Hideki; Tanaka, Kazuya

    2014-01-01

    To investigate the effect of biofilms on selenium migration, we examined selenite reduction by biofilms of an iron-reducing bacterium, Shewanella putrefaciens, under anaerobic conditions. The biofilms were grown under static conditions on culture cover glasses coated with poly-L-lysine. Optical microscopic observation of the biofilms after staining with 0.1% crystal violet solution revealed that the cells were surrounded by filamentous extracellular polymer substances. Exposure of the biofilms to aqueous selenite resulted in the formation of red precipitates, which were assigned to nanoparticulate elemental selenium using X-ray absorption near-edge structure analysis. Micrographic observation showed that the precipitates immobilized at the biofilms. We also examined the selenite reduction in the presence of Fe(III)-citrate complex. In this case, a dark brown precipitate formed at the biofilms. X-ray absorption near-edge structure analysis revealed that the precipitate was a mixed compound with elemental selenium and iron selenide. These findings indicate that biofilms of iron-reducing bacteria in the environment can immobilize selenium by reducing Se(IV) to Se(0), and Fe(III)-citrate complex promotes the reduction of Se(0) to Se(-II). (author)

  17. Cycloadditions to Epoxides Catalyzed by GroupIII-V Transition-Metal Complexes

    KAUST Repository

    D'Elia, Valerio

    2015-05-25

    Complexes of groupIII-V transition metals are gaining increasing importance as Lewis acid catalysts for the cycloaddition of dipolarophiles to epoxides. This review examines the latest reports, including homogeneous and heterogeneous applications. The pivotal step for the cycloaddition reactions is the ring opening of the epoxide following activation by the Lewis acid. Two modes of cleavage (C-C versus C-O) have been identified depending primarily on the substitution pattern of the epoxide, with lesser influence observed from the Lewis acid employed. The widely studied cycloaddition of CO2 to epoxides to afford cyclic carbonates (C-O bond cleavage) has been scrutinized in terms of catalytic efficiency and reaction mechanism, showing that unsophisticated complexes of groupIII-V transition metals are excellent molecular catalysts. These metals have been incorporated, as well, in highly performing, recyclable heterogeneous catalysts. Cycloadditions to epoxides with other dipolarophiles (alkynes, imines, indoles) have been conducted with scandium triflate with remarkable performances (C-C bond cleavage). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Cycloadditions to Epoxides Catalyzed by GroupIII-V Transition-Metal Complexes

    KAUST Repository

    D'Elia, Valerio; Pelletier, Jeremie; Basset, Jean-Marie

    2015-01-01

    Complexes of groupIII-V transition metals are gaining increasing importance as Lewis acid catalysts for the cycloaddition of dipolarophiles to epoxides. This review examines the latest reports, including homogeneous and heterogeneous applications. The pivotal step for the cycloaddition reactions is the ring opening of the epoxide following activation by the Lewis acid. Two modes of cleavage (C-C versus C-O) have been identified depending primarily on the substitution pattern of the epoxide, with lesser influence observed from the Lewis acid employed. The widely studied cycloaddition of CO2 to epoxides to afford cyclic carbonates (C-O bond cleavage) has been scrutinized in terms of catalytic efficiency and reaction mechanism, showing that unsophisticated complexes of groupIII-V transition metals are excellent molecular catalysts. These metals have been incorporated, as well, in highly performing, recyclable heterogeneous catalysts. Cycloadditions to epoxides with other dipolarophiles (alkynes, imines, indoles) have been conducted with scandium triflate with remarkable performances (C-C bond cleavage). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Kinetic of liquid-liquid extraction for uranyl nitrate and actinides (III) and lanthanides (III) nitrates by amide extractants; Cinetique d`extraction liquide-liquide du nitrate d`uranyle et des nitrates d`actinides (III) et de lanthanides (III) par des extractants a fonction amide

    Energy Technology Data Exchange (ETDEWEB)

    Toulemonde, V [CEA Centre d` Etudes Nucleaires de Saclay, 91 -Gif-sur-Yvette (France); [CEA Centre d` Etudes de la Vallee du Rhone, 30 -Marcoule (France). Dept. d` Exploitation du Retraitement et de Demantelement

    1995-12-20

    The kinetics of liquid-liquid extraction by amide extractants have been investigated for uranyl nitrate (monoamide extractants), actinides (III) and lanthanides (III) nitrates (diamide extractants). The transfer of the metallic species from the aqueous phase to the organic phase was studied using two experimental devices: ARMOLLEX (Argonne Modified Lewis cell for Liquid Liquid Extraction) and RSC (Rotating Stabilized Cell). The main conclusions are: for the extraction of uranyl nitrate by DEHDMBA monoamide, the rate-controlling step is the complexation of the species at the interface of the two liquids. Thus, an absorption-desorption (according to Langmuir theory) reaction mechanism was proposed; for the extraction of actinides (III) and lanthanides (III) nitrates in nitric acid media by DMDBTDMA diamide, the kinetic is also limited by interfacial reactions. The behavior of Americium and Europium is very similar as fare as their reaction kinetics are concerned. (author). 89 refs.

  20. Leaching of irradiated polymers: solution characterization and actinides complexation

    International Nuclear Information System (INIS)

    Fromentin, Elodie

    2017-01-01

    The first aim of this work is to study the degradation of an industrial poly-esterurethane (PURm) by radio-oxidation and then by leaching in an alkaline aqueous solution. The second aim is to measure the complexing power of hydro-soluble degradation products (HDP) with actinides. To reach these goals, PURm was first characterized and then radio-oxidized at room temperature with γ rays up to 10 MGy. Second, it was leached at pH 13.3 at different temperature values. Numerous analytical techniques were employed in order to characterize the HDP which were obtained. Europium(III) was used as an analogue of actinides(III) and the behavior of HDP with europium(III) was analyzed by time-resolved luminescence spectroscopy (TRLS). Whatever the dose received by PURm, adipic acid and butane-1,4-diol are the two main HDP in leachates. The leaching data acquired at 40 and 60 C, on the 1 MGy radio-oxidized PURm, correlate with the model given by Yoon et al. (1997). However, the data at room temperature (22 C in average) are not in agreement with the model. Nevertheless, it seems that the plateau which was reached at long-term leaching is the same whatever the temperature used in this study. The results allow to conclude that the predominant mechanism occurring during the leaching of unirradiated and radio-oxidized PURm in an alkaline medium is the hydrolysis of the soft segments ester groups. The complexation of europium(III) by HDP in alkaline medium was demonstrated. The measurement of the complexing power and the identification of ligands was achieved under certain conditions. (author) [fr

  1. Reactivity of tris(acetylacetonato) iron(III) with tridentate [ONO] donor Schiff base as an access to newer mixed-ligand iron(III) complexes

    Science.gov (United States)

    Bhattacharjee, Chira R.; Goswami, Pankaj; Pramanik, Harun A. R.; Paul, Pradip C.; Mondal, Paritosh

    2011-05-01

    Two new mixed-ligand iron(III) complexes, [Fe(L n)(acac)(C 2H 5OH)] incorporating coordinated ethanol from the reaction solvent were accessed from the reaction of [Fe(acac) 3] with [ONO] donor dibasic tridentate unsymmetrical Schiff base ligands derived from condensation of 2-hydroxy-1-napthaldehyde with 2-aminophenol (H 2L 1) or 2-aminobenzoic acid (H 2L 2). The thermal study (TGA-DTA) provided evidence for weakly bound ethanol which is readily substituted by neutral N-donor molecule imidazole, benzimidazole or pyridine to produce an array of newer complexes, [Fe(L n)(acac)X] ( n = 1, 2; X = Im, Bim, Py). The compounds were characterized by elemental analyses, FT-IR, UV-vis, solution electrical conductivity, FAB mass, 1H and 13C NMR spectroscopy. Room temperature magnetic susceptibility measurements ( μeff ˜ 5.8 B.M.) are consistent with spin-free octahedral iron(III) complexes. Cyclic voltammetry of ethanol complexes revealed a quasi-reversible one electron redox response (Δ Ep > 100 mV) for the Fe(III)/Fe(II) couple. Low half wave redox potential ( E1/2) values suggested easy redox susceptibility. The ground state geometries of the ethanol and imidazole complexes have been ascertained to be distorted octahedral by density functional theory using DMol3 program at BLYP/DNP level.

  2. A family of acetato-diphenoxo triply bridged dimetallic Zn(II)Ln(III) complexes: SMM behavior and luminescent properties.

    Science.gov (United States)

    Oyarzabal, Itziar; Artetxe, Beñat; Rodríguez-Diéguez, Antonio; García, JoséÁngel; Seco, José Manuel; Colacio, Enrique

    2016-06-21

    Eleven dimetallic Zn(II)-Ln(III) complexes of the general formula [Zn(µ-L)(µ-OAc)Ln(NO3)2]·CH3CN (Ln(III) = Pr (1), Nd (2), Sm (3), Eu (4), Gd (5), Tb (6), Dy (7), Ho (8), Er (9), Tm (10), Yb (11)) have been prepared in a one-pot reaction from the compartmental ligand N,N'-dimethyl-N,N'-bis(2-hydroxy-3-formyl-5-bromo-benzyl)ethylenediamine (H2L). In all these complexes, the Zn(II) ions occupy the internal N2O2 site whereas the Ln(III) ions show preference for the O4 external site. Both metallic ions are bridged by an acetate bridge, giving rise to triple mixed diphenoxido/acetate bridged Zn(II)Ln(III) compounds. The Nd, Dy, Er and Yb complexes exhibit field induced single-ion magnet (SIM) behaviour, with Ueff values ranging from 14.12 to 41.55 K. The Er complex shows two relaxation processes, but only the second relaxation process with an energy barrier of 21.0 K has been characterized. The chromophoric L(2-) ligand is able to act as an "antenna" group, sensitizing the near-infrared (NIR) Nd(III) and Yb(III)-based luminescence in complexes 2 and 11 and therefore, both compounds can be considered as magneto-luminescent materials. In addition, the Sm(III), Eu(III) and Tb(III) derivatives exhibit characteristic emissions in the visible region.

  3. Thermal and biological evolution of Fe(III)-Sulfanilamide complexes synthesized by green strategy

    Science.gov (United States)

    Prajapat, Garima; Rathore, Uma; Gupta, Rama; Bhojak, N.

    2018-05-01

    Sulfonamides belong to a category of sulfadrugs, that are widely used as antibiotic medicines. Their metal complexes, also called Metallodrugs, are known to have diverse pharmacological applications and are significantly used as therapeutic agents for treatment of several human diseases. Fe(III) complexes of two sulfonamides, namely Sulfanilamide and Sulfadiazine have been synthesized by the method of Microwave Assisted Organic Synthesis (MAOS), using acetone as solvent medium. Presence of excellent donor atoms such as N and O, induce these drugs to exhibit a chelating behavior with the metal ion, and to act as bidentate ligands. Both the complexes were found to have four coordinated, tetrahedral geometry with one molecule of water of crystallisation. Thermal decomposition studies were carried out in an inert nitrogen atmosphere by Thermogravimetric (TGA) and Derivative Thermogravimetric (DTA) analysis. Interpretation of thermograms have been done to evaluate various kinetic and thermodynamic parameters, using integral method of Coats and Redfern. The antibacterial activity for both complexes have been screened against E.coli, S. aureus and B. subtilis.

  4. TTC19 Plays a Husbandry Role on UQCRFS1 Turnover in the Biogenesis of Mitochondrial Respiratory Complex III.

    Science.gov (United States)

    Bottani, Emanuela; Cerutti, Raffaele; Harbour, Michael E; Ravaglia, Sabrina; Dogan, Sukru Anil; Giordano, Carla; Fearnley, Ian M; D'Amati, Giulia; Viscomi, Carlo; Fernandez-Vizarra, Erika; Zeviani, Massimo

    2017-07-06

    Loss-of-function mutations in TTC19 (tetra-tricopeptide repeat domain 19) have been associated with severe neurological phenotypes and mitochondrial respiratory chain complex III deficiency. We previously demonstrated the mitochondrial localization of TTC19 and its link with complex III biogenesis. Here we provide detailed insight into the mechanistic role of TTC19, by investigating a Ttc19 ?/? mouse model that shows progressive neurological and metabolic decline, decreased complex III activity, and increased production of reactive oxygen species. By using both the Ttc19 ?/? mouse model and a range of human cell lines, we demonstrate that TTC19 binds to the fully assembled complex III dimer, i.e., after the incorporation of the iron-sulfur Rieske protein (UQCRFS1). The in situ maturation of UQCRFS1 produces N-terminal polypeptides, which remain bound to holocomplex III. We show that, in normal conditions, these UQCRFS1 fragments are rapidly removed, but when TTC19 is absent they accumulate within complex III, causing its structural and functional impairment. Copyright © 2017. Published by Elsevier Inc.

  5. "Switching on" the properties of single-molecule magnetism in triangular manganese(III) complexes.

    Science.gov (United States)

    Stamatatos, Theocharis C; Foguet-Albiol, Dolos; Lee, Sheng-Chiang; Stoumpos, Constantinos C; Raptopoulou, Catherine P; Terzis, Aris; Wernsdorfer, Wolfgang; Hill, Stephen O; Perlepes, Spyros P; Christou, George

    2007-08-01

    The reaction between oxide-centered, triangular [MnIII3O(O2CR)6(py)3](ClO4) (R = Me (1), Et (2), Ph (3)) compounds and methyl 2-pyridyl ketone oxime (mpkoH) affords a new family of Mn/carboxylato/oximato complexes, [MnIII3O(O2CR)3(mpko)3](ClO4) [R = Me (4), Et (5), and Ph (6)]. As in 1-3, the cations of 4-6 contain an [MnIII3(mu3-O)]7+ triangular core, but with each Mn2 edge now bridged by an eta1:eta1:mu-RCO2- and an eta1:eta1:eta1:mu-mpko- group. The tridentate binding mode of the latter causes a buckling of the formerly planar [MnIII3(mu3-O)]7+ core, resulting in a relative twisting of the three MnIII octahedra and the central O2- ion now lying approximately 0.3 A above the Mn3 plane. This structural distortion leads to ferromagnetic exchange interactions within the molecule and a resulting S = 6 ground state. Fits of dc magnetization data for 4-6 collected in the 1.8-10.0 K and 10-70 kG ranges confirmed S = 6 ground states, and gave the following D and g values: -0.34 cm(-1) and 1.92 for 4, -0.34 cm(-1) and 1.93 for 5, and -0.35 cm(-1) and 1.99 for 6, where D is the axial zero-field splitting (anisotropy) parameter. Complexes 4-6 all exhibit frequency-dependent out-of-phase (chi" M) ac susceptibility signals suggesting them possibly to be single-molecule magnets (SMMs). Relaxation rate vs T data for complex 4 down to 1.8 K obtained from the chi" M vs T studies were supplemented with rate vs T data measured to 0.04 K via magnetization vs time decay studies, and these were used to construct Arrhenius plots from which was obtained the effective barrier to relaxation (Ueff) of 10.9 K. Magnetization vs dc field sweeps on single-crystals of 4.3CH2Cl2 displayed hysteresis loops exhibiting steps due to quantum tunneling of magnetization (QTM). The loops were essentially temperature-independent below approximately 0.3 K, indicating only ground-state QTM between the lowest-lying Ms = +/-6 levels. Complexes 4-6 are thus confirmed as the first triangular SMMs. High

  6. Different-ligand coordination europium compounds with dibenzoylmethane, nitrate-group, and hexamethylphosphotriamide

    International Nuclear Information System (INIS)

    Karasev, V.E.; Botova, I.N.

    1988-01-01

    Some different-ligand europium complexes with dibenzoylmethane (DBM), hexamethylphosphotriamide (HMPA) and NO 3 -group of composition: Eu(NO 3 ) 3 x3HMPAx2H 2 O, Eu(NO 3 ) 2 xDBMx2HMPA, EuNO 3 x(DBM) 2 x2HMPA and Eu(DBM) 3 xHMPA are synthesized. Individuality of each complex is confirmed by methods of chemical, IR spectroscopic, luminescent, thermogravimetric analyses. Integral intensities of luminescence of synthesized complexes are measured, their excitation spectra in the crystal state at 77 K in the 200-600 nm range are studied

  7. Cytogenotoxic effects of two potential anticancer Ruthenium(III Schiff Bases complexes

    Directory of Open Access Journals (Sweden)

    Izet Eminovic

    2016-10-01

    Full Text Available Introduction: Treatment of cancer has been subject of great interest. Researchers are continuously searching for new medicines. In this sense, ruthenium complexes have big potential. Some evidences suggest that ruthenium compounds possess anticancer activities. We synthesized two recently published ruthenium(III complexes with bidentate O,N and tridentate O,O,N Schiff bases derived from 5-substituted salicylaldehyde and aminophenol or anilineare. These compounds showed affinity for binding to the DNA molecule, however, insufficient data are available regarding their possible toxic effects on biological systems.Methods: In the present study we evaluated genotoxic, cytotoxic, and cytostatic effects of Na[RuCl2(L12] and Na[Ru(L22], using the Allium cepa assay.Results: Different toxic effects were observed depending on the substance, tested concentration, and endpoint measured. In general, the tested compounds significantly lowered the root growth and mitotic index values as compared to the control group. Additionally, a wide range of abnormal mitotic stages, both clastogenic and non-clastogenic were observed in the treated cells. Na[RuCl2(L12] significantly increased the frequency of sticky metaphases, chromosome bridges, micronuclei, impaired chromosome segregation, as well as number of apoptotic and necrotic cells over the controls. In contrast, Na[Ru(L22] did not show significant evidence of genotoxicity with regard to chromosome aberrations and micronuclei, however, significant differences were detected in the number of apoptotic and necrotic cells when the highest concentration was applied.Conclusions: In this study we demonstrated antiproliferative effects of Na[RuCl2(L12] and Na[Ru(L22]. At clinical level, these results could be interesting for further studies on anticancer potential of the ruthenium(III complexes using animal models.

  8. Structure and luminescent investigation of new Ln(III)-TTA complexes containing N-methyl-ε-caprolactam as ligand

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Alex Santos, E-mail: alexb@ifes.edu.br [Coordenadoria de Química e Biologia, IFES, Vitória, ES 29040-780 (Brazil); Caliman, Ewerton Valadares [Coordenadoria de Engenharia Metalúrgica, IFES, Vitória, ES 29040-780 (Brazil); Dutra, José Diogo L. [Departamento de Química Fundamental, UFPE, Recife, PE 50590-470 (Brazil); Da Silva, Jeferson G. [Departamento de Farmácia, UFJF, Governador Valadares, MG 35010-17 (Brazil); Araujo, Maria Helena, E-mail: maria.araujo@pq.cnpq.br [Departamento de Química, UFMG, Belo Horizonte, MG 31270-901 (Brazil)

    2016-02-15

    The synthesis and photoluminescent properties of Ln(III)-TTA complexes (Ln=Eu(III) and Sm(III) ions; TTA=3-thenoyltrifluoroacetonate) with N-methyl-ε-caprolactam (NMC) are reported. The Ln complexes were characterized by elemental analysis, complexometric titration with EDTA and infrared spectroscopy. The molecular structures of the [Eu(TTA){sub 3}(NMC)(H{sub 2}O)] and [Sm(TTA){sub 3}(NMC)(H{sub 2}O)]·H{sub 2}O compounds were determined by single crystal X-ray crystallography. In these structures, the three TTA molecules are coordinated to the metal in anionic form as bidentate ligands, while the H{sub 2}O and NMC molecules are coordinated to the metal in neutral form as monodentated ligands. The coordination polyhedron around the Ln(III) atom can be described as square antiprismatic molecular geometry. The geometry of the [Eu(TTA){sub 3}(NMC)(H{sub 2}O)] complex was optimized with the Sparkle/RM1 model for Ln(III) complexes, allowing analysis of intramolecular energy transfer processes of the Eu(III) compound. The spectroscopic properties of the 4f{sup 6} intraconfigurational transitions of the Eu(III) complex were then studied experimentally and theoretically. The low value of emission quantum efficiency of {sup 5}D{sub 0} emitting level (η) of Eu(III) ion (ca. 36%) is due to the vibrational modes of the water molecule that act as luminescence quenching. In addition, the luminescence decay curves, the experimental intensity parameters (Ω{sub λ}), lifetimes (τ), radiative (A{sub rad}) and non-radiative (A{sub nrad}) decay rates, theoretical quantum yield (q{sub cal}) were also determined and discussed. - Highlights: • New Ln-TTA complexes with lactam were obtained and their luminescence investigated. • Jablonsky diagram for the Eu(III) complex shows the main channel for the IET process. • Data confirm the potentiality of the Eu(III) complex to produce red luminescence. • LUMPAC has provided useful information on the luminescence of the Eu(III

  9. A rhodium(III) complex for high-affinity DNA base-pair mismatch recognition

    Science.gov (United States)

    Junicke, Henrik; Hart, Jonathan R.; Kisko, Jennifer; Glebov, Oleg; Kirsch, Ilan R.; Barton, Jacqueline K.

    2003-01-01

    A rhodium(III) complex, rac-[Rh(bpy)2phzi]3+ (bpy, 2,2′-bipyridine; phzi, benzo[a]phenazine-5,6-quinone diimine) has been designed as a sterically demanding intercalator targeted to destabilized mismatched sites in double-helical DNA. The complex is readily synthesized by condensation of the phenazine quinone with the corresponding diammine complex. Upon photoactivation, the complex promotes direct strand scission at single-base mismatch sites within the DNA duplex. As with the parent mismatch-specific reagent, [Rh(bpy)2(chrysi)]3+ [chrysene-5,6-quinone diimine (chrysi)], mismatch selectivity depends on the helix destabilization associated with mispairing. Unlike the parent chrysi complex, the phzi analogue binds and cleaves with high affinity and efficiency. The specific binding constants for CA, CC, and CT mismatches within a 31-mer oligonucleotide duplex are 0.3, 1, and 6 × 107 M−1, respectively; site-specific photocleavage is evident at nanomolar concentrations. Moreover, the specificity, defined as the ratio in binding affinities for mispaired vs. well paired sites, is maintained. The increase in affinity is attributed to greater stability in the mismatched site associated with stacking by the heterocyclic aromatic ligand. The high-affinity complex is also applied in the differential cleavage of DNA obtained from cell lines deficient in mismatch repair vs. those proficient in mismatch repair. Agreement is found between photocleavage by the mismatch-specific probes and deficiency in mismatch repair. This mismatch-specific targeting, therefore, offers a potential strategy for new chemotherapeutic design. PMID:12610209

  10. Gadolinium(III-DOTA Complex Functionalized with BODIPY as a Potential Bimodal Contrast Agent for MRI and Optical Imaging

    Directory of Open Access Journals (Sweden)

    Matthias Ceulemans

    2015-11-01

    Full Text Available The synthesis and characterization of a novel gadolinium(III DOTA complex functionalized with a boron-dipyrromethene derivative (BODIPY is described. The assembly of the complex relies on azide diazotransfer chemistry in a copper tube flow reactor. The azide thus formed is coupled directly with an alkyne via click chemistry, resulting into a paramagnetic and luminescent gadolinium(III complex. Luminescent data and relaxometric properties of the complex have been evaluated, suggesting the potential applicability of the complexes as a bimodal contrast agent for magnetic resonance and optical imaging. The complex displays a bright emission at 523 nm with an absorption maximum of 507 nm and high quantum yields of up to 83% in water. The proton relaxivity of the complex measured at 310 K and at frequencies of 20 and 60 MHz had the values of 3.9 and 3.6 s−1·mM−1, respectively.

  11. Properties and reactivities of pentadentate ethylenediaminetetraacetate complexes of ruthenium(III) and -(II)

    International Nuclear Information System (INIS)

    Matsubara, T.; Creutz, C.

    1979-01-01

    The reaction of the pentadentate edta complex of ruthenium(III) with various entering ligands L has been studied as a function of pH, temperature, and L at 0.2 M ionic strength in aqueous solution. Over the pH range 0.8 to 8.5, the species Ru/sup III/(edta)H 2 O - is the sole form reactive in the substitution processes. Both forward (k 1 ) and reverse (k/sub -1/) rate constants Ru(edta)H 2 O - + L in equilibrium (k 1 ,k/sub -1/) Ru(edta)L - + H 2 O have been determined, as well as activation parameters for the complexation (k 1 ) process (L, k 1 in M -1 s -1 (25 0 C), k/sub -1/ in s -1 (25 0 C), ΔH 1 + in kcal mol -1 , ΔS 1 + in cal deg -1 mol -1 ): acetonitrile, 30 +- 7, 3.2 +- 0.2, 8.3 +- 0.5, -24 +- 4; thiocyanate, 270 +- 20, 0.5 +- 0.1, 8.9 +- 0.5, -18 +- 3; pyridine, 6300 +- 500, 0.061 +- 0.002; isonicotinamide, 8300 +- 600, 0.7 +- 0.2, 6.6 +- 0.5, -19 +- 3; pyrazine, 20,000 +- 1000, 2.0 +- 0.5, 5.7 +- 0.5, -20 +- 3. Forward rate constants for the analogous substitution reaction for Ru/sup II/(edta) H 2 O 2- (25 0 C, 0.2 M ionic strength) are as follows: thiocyanate, 2.7 +- 0.2 M -1 s -1 ; acetonitrile, 13 +- 1 M -1 s -1 ; isonicotinamide, 30 +- 15 M -1 s -1 . The substitution reactions of Ru/sup III/(edta)H 2 O - proceed by an associative mechanism, while those of Ru/sup II/(edta)H 2 O 2 - appear to be dissociative in nature. Spectra and reduction potentials for the Ru(edta)L/sup -/2-/ complexes are reported. 4 figures, 11 tables

  12. Effect of Eu(III) on the degradation of malic acid by Pseudomonas fluorescens

    International Nuclear Information System (INIS)

    Nankawa, T.; Ozaki, T.; Ohnuki, T.; Suzuki, Y.; Francis, A.J.

    2005-01-01

    Full text of publication follows: The transuranic elements, such as Am(III) and Cm(III), are highly toxic because they emit high-energy α particles and have long half-lives. To estimate their long-term environmental behavior, we need to elucidate degradation of actinide-organic complexes by microorganisms. We studied the biodegradation of Eu(III)-malic acid complexes by Pseudomonas fluorescens. Malic acid is ubiquitous in the environment and is one of the microbial metabolites that is part of the tri-carboxylic acid (TCA) cycle. Europium(III) is a good analogue for Am(III) and Cm(III). To investigate the effect of Eu(III) on the degradation of malic acid by P. fluorescens, we compared the degradation behavior of Eu(III)-malic acid complexes to that of Fe(III) and Al(III)-malic acid complexes. In the medium containing 1 mM malic acid and 0-0.5 mM Fe(III), malic acid was degraded completely. In the medium containing 1 mM malic acid and 0.05-0.5 mM Al(III), malic acid was degraded until the concentration of malic acid became equal to that of Al(III), indicating that Al(III)-malic acid complex with 1: 1 molar ratio was recalcitrant to biodegradation. In the medium containing 1 mM malic acid and 0.05-0.5 mM Eu(III), degradation of malic acid was not observed. The effect of metals on degradation of malic acid was in the order of Fe(III) < Al(III) < Eu(III). The stability constants of 1:1 Fe(III)-, Al(III)-, and Eu(III)-malic acid complexes are 7.1, 4.6, and 4.9, respectively. These results indicate that degradability of malic acid does not depend on the stability constants of metal-malic acid complexes. We found that 10 mM malic acid was degraded in the presence of 0.05 and 0.1 mM Eu(III) but 1 mM malic acid was not degraded in the presence of 0.05 and 0.1 mM Eu(III). The degradation rate of malic acid increased with a decreasing ratio of Eu(III) to malic acid. (authors)

  13. Study of the europium behavior in aqueous media

    International Nuclear Information System (INIS)

    Fernandez R, E.; Jimenez R, M.; Solache R, M.; Martinez M, V.

    1999-01-01

    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

  14. Phosphorescence Imaging of Living Cells with Amino Acid-Functionalized Tris(2-phenylpyridine)iridium(III) Complexes

    NARCIS (Netherlands)

    Steunenberg, P.; Ruggi, A.; Berg, van den N.S.; Buckle, T.; Kuil, J.; Leeuwen, van F.W.B.; Velders, A.H.

    2012-01-01

    A series of nine luminescent cyclometalated octahedral iridium(III) tris(2-phenylpyridine) complexes has been synthesized, functionalized with three different amino acids (glycine, alanine, and lysine), on one, two, or all three of the phenylpyridine ligands. All starting complexes and final

  15. Enthalpies of formation of europium alkoxides: What lessons can be drawn from them

    International Nuclear Information System (INIS)

    Branco, Joaquim B.; Carretas, José M.; Epple, Matthias; Cruz, Adelaide; Pires de Matos, A.; Leal, João Paulo

    2014-01-01

    Highlights: • First time measurement of europium(II) alkoxides enthalpy of formation. • Calculation of alkoxides thermochemical radii and M–O distances in this environment. • Comparison of experimental EXAFS distance with the calculated ones. • Hints on the type of bond existing in these compounds. • Correlation of bond type and possible use as catalysts. - Abstract: The synthesis and characterization of two europium alkoxides, Eu(OCH 3 ) 2 and Eu(OC 2 H 5 ) 2 , were described. For the first time the enthalpies of formation of divalent lanthanide alkoxides were determined by using reaction-solution calorimetry. The values obtained are Δ f H 0 [Eu(OCH 3 ) 2 ,cr] = −850.5 ± 5.0 kJ/mol and Δ f H 0 [Eu(OC 2 H 5 ) 2 ,cr] = −902.5 ± 5.5 kJ/mol, respectively. Since these compounds have a large use as catalysts or catalysts precursors, the first step of the reaction of them with CO 2 was addressed, which permits to have an idea of the kind of bond involved in those compounds. Moreover, insertion of CO 2 in the europium oxygen bond and formation of metal carboxylate complexes, is in both cases presumably bidentate

  16. 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).

  17. Hydrogen-Bonding Interactions Trigger a Spin-Flip in Iron(III) Porphyrin Complexes**

    Science.gov (United States)

    Sahoo, Dipankar; Quesne, Matthew G; de Visser, Sam P; Rath, Sankar Prasad

    2015-01-01

    A key step in cytochrome P450 catalysis includes the spin-state crossing from low spin to high spin upon substrate binding and subsequent reduction of the heme. Clearly, a weak perturbation in P450 enzymes triggers a spin-state crossing. However, the origin of the process whereby enzymes reorganize their active site through external perturbations, such as hydrogen bonding, is still poorly understood. We have thus studied the impact of hydrogen-bonding interactions on the electronic structure of a five-coordinate iron(III) octaethyltetraarylporphyrin chloride. The spin state of the metal was found to switch reversibly between high (S=5/2) and intermediate spin (S=3/2) with hydrogen bonding. Our study highlights the possible effects and importance of hydrogen-bonding interactions in heme proteins. This is the first example of a synthetic iron(III) complex that can reversibly change its spin state between a high and an intermediate state through weak external perturbations. PMID:26109743

  18. Actinide complexation kinetics: rate and mechanism of dioxoneptunium (V) reaction with chlorophosphonazo III

    International Nuclear Information System (INIS)

    Fugate, G.; Feil-Jenkins, J.F.; Sullivan, J.C.; Nash, K.L.

    1996-12-01

    Rates of complex formation and dissociation in NpO 2 + - Chlorophosphonazo III (2,7-bis(4-chloro-2-phosphonobenzeneazo)-1,8- dihydroxynapthalene-3,6-disulfonic acid)(CLIII) were investigated by stopped-flow spectrophotometry. Also, limited studies were made of the rates of reaction of La 3+ , Eu 3+ , Dy 3+ , and Fe 3+ with CLIII. Rate determining step in each system is an intramolecular process, the NpO 2 + -CLIII reaction proceeding by a first order approach to equilibrium in the acid range from 0.1 to 1.0 M. Complex formation occurs independent of acidity, while both acid dependent and independent dissociation pathways are observed. Activation parameters for the complex formation reaction are ΔH=46.2±0.3 kJ/m and ΔS=7± J/mK (I=1.0 M); these for the acid dependent and independent dissociation pathways are ΔH=38.8±0.6 kJ/m, ΔS=-96±18 J/mK, ΔH=70.0± kJ/m, and ΔS=17±1 J/mK, respectively. An isokinetic relationship is observed between the activation parameters for CLIII complex formation with NpO 2 + , UO 2 2+ , Th 4+ , and Zr 4+ . Rates of CLIII complex formation reactions for Fe 3+ , Zr 4+ , NpO 2 + , UO 2 2+ , Th 4+ , La 3+ , Eu 3+ , and Dy 3+ correlate with cation radius rather than charge/radius ratio

  19. The Alternative complex III: properties and possible mechanisms for electron transfer and energy conservation.

    Science.gov (United States)

    Refojo, Patrícia N; Teixeira, Miguel; Pereira, Manuela M

    2012-10-01

    Alternative complexes III (ACIII) are recently identified membrane-bound enzymes that replace functionally the cytochrome bc(1/)b(6)f complexes. In general, ACIII are composed of four transmembrane proteins and three peripheral subunits that contain iron-sulfur centers and C-type hemes. ACIII are built by a combination of modules present in different enzyme families, namely the complex iron-sulfur molybdenum containing enzymes. In this article a historical perspective on the investigation of ACIII is presented, followed by an overview of the present knowledge on these enzymes. Electron transfer pathways within the protein are discussed taking into account possible different locations (cytoplasmatic or periplasmatic) of the iron-sulfur containing protein and their contribution to energy conservation. In this way several hypotheses for energy conservation modes are raised including linear and bifurcating electron transfer pathways. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012). Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Characterization of metal-bound water in bioactive Fe(III)-cyclophane complexes

    Science.gov (United States)

    Salazar-Medina, A. J.; Gámez-Corrales, R.; Ramírez, J. Z.; González-Aguilar, G. A.; Velázquez-Contreras, E. F.

    2018-02-01

    Binuclear Fe(III) complexes, Fe2PO and Fe2PC, have functions of antioxidants as well as superoxide dismutase and peroxidase mimickers. The role of water molecules in the non-cytotoxic properties of these complexes have been studied by thermogravimetric and IR/Raman-spectroscopic methods. The thermogravimetric analysis of Fe2PO shows the presence of nine water molecules (Fe2PO·9H2O), three of which are directly coordinated to the metallic ion; the remaining six molecules occupy the secondary coordination sphere. For Fe2PC, eight water molecules were detected (Fe2PC·8H2O), and only one of them directly coordinates to the metallic ion. IR/Raman spectrum analyses corroborate the presence of water molecules in both metallic complexes and the mode of coordination to the ligand, on the basis of bands characteristic of hydration water at ∼3300 cm-1 and bands of adsorbed water between 430 and 490 cm-1. A pentacoordinate geometry is proposed for Fe2PO and a hexacoordinated geometry for Fe2PC. Those results are consistent with theoretical calculations performed through a semiempirical PM7 method. The presence of coordinated water molecules is closely related to the reactivity of Fe2PO and Fe2PC in solution.

  1. Near-infrared electroluminescence from double-emission-layers devices based on Ytterbium (III) complexes

    International Nuclear Information System (INIS)

    Li Zhefeng; Zhang Hongjie; Yu Jiangbo

    2012-01-01

    We investigated near-infrared electroluminescence properties of two lanthanide complexes Yb(PMBP) 3 Bath [PMBP = tris(1-phenyl-3-methyl-4-(4-tert-butylbenzacyl)-5-pyrazolone); Bath = bathophenanthroline] and Yb(PMIP) 3 TP 2 [PMIP = tris(1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone); TP = triphenyl phosphine oxide] by fabricated the double-emission-layers devices. From the device characteristics, it is known that holes are easier to transport in Yb(PMIP) 3 TP 2 layer and electrons are easier to transport in Yb(PMBP) 3 Bath layer, at the same time, both of the two complexes can be acted as emission layers in the device. The recombination region of carriers has been confined in the interface of Yb(PMIP) 3 TP 2 /Yb(PMBP) 3 Bath, and pure Yb 3+ ion characteristic emission centered at 980 nm has been obtained. The device shows the maximum near-infrared irradiance as 14.7 mW/m 2 at the applied voltage of 17.8 V. - Highlights: ► Near-infrared electroluminescent devices with Yb(III) complexes as emission layers. ► Double-emission layer device structure introduced to balance carriers. ► Improved performance of double-emission layer device.

  2. The Chlamydia type III secretion system C-ring engages a chaperone-effector protein complex.

    Directory of Open Access Journals (Sweden)

    Kris E Spaeth

    2009-09-01

    Full Text Available In Gram-negative bacterial pathogens, specialized chaperones bind to secreted effector proteins and maintain them in a partially unfolded form competent for translocation by type III secretion systems/injectisomes. How diverse sets of effector-chaperone complexes are recognized by injectisomes is unclear. Here we describe a new mechanism of effector-chaperone recognition by the Chlamydia injectisome, a unique and ancestral line of these evolutionarily conserved secretion systems. By yeast two-hybrid analysis we identified networks of Chlamydia-specific proteins that interacted with the basal structure of the injectisome, including two hubs of protein-protein interactions that linked known secreted effector proteins to CdsQ, the putative cytoplasmic C-ring component of the secretion apparatus. One of these protein-interaction hubs is defined by Ct260/Mcsc (Multiple cargo secretion chaperone. Mcsc binds to and stabilizes at least two secreted hydrophobic proteins, Cap1 and Ct618, that localize to the membrane of the pathogenic vacuole ("inclusion". The resulting complexes bind to CdsQ, suggesting that in Chlamydia, the C-ring of the injectisome mediates the recognition of a subset of inclusion membrane proteins in complex with their chaperone. The selective recognition of inclusion membrane proteins by chaperones may provide a mechanism to co-ordinate the translocation of subsets of inclusion membrane proteins at different stages in infection.

  3. General synthesis of (salen)ruthenium(III) complexes via N...N coupling of (salen)ruthenium(VI) nitrides.

    Science.gov (United States)

    Man, Wai-Lun; Kwong, Hoi-Ki; Lam, William W Y; Xiang, Jing; Wong, Tsz-Wing; Lam, Wing-Hong; Wong, Wing-Tak; Peng, Shie-Ming; Lau, Tai-Chu

    2008-07-07

    Reaction of [Ru (VI)(N)(L (1))(MeOH)] (+) (L (1) = N, N'-bis(salicylidene)- o-cyclohexylenediamine dianion) with excess pyridine in CH 3CN produces [Ru (III)(L (1))(py) 2] (+) and N 2. The proposed mechanism involves initial equilibrium formation of [Ru (VI)(N)(L (1))(py)] (+), which undergoes rapid N...N coupling to produce [(py)(L (1))Ru (III) N N-Ru (III)(L (1))(py)] (2+); this is followed by pyridine substituion to give the final product. This ligand-induced N...N coupling of Ru (VI)N is utilized in the preparation of a series of new ruthenium(III) salen complexes, [Ru (III)(L)(X) 2] (+/-) (L = salen ligand; X = H 2O, 1-MeIm, py, Me 2SO, PhNH 2, ( t )BuNH 2, Cl (-) or CN (-)). The structures of [Ru (III)(L (1))(NH 2Ph) 2](PF 6) ( 6), K[Ru (III)(L (1))(CN) 2] ( 9), [Ru (III)(L (2))(NCCH 3) 2][Au (I)(CN) 2] ( 11) (L (2) = N, N'-bis(salicylidene)- o-phenylenediamine dianion) and [N ( n )Bu 4][Ru (III)(L (3))Cl 2] ( 12) (L (3) = N, N'-bis(salicylidene)ethylenediamine dianion) have been determined by X-ray crystallography.

  4. Study of the selectivity of poly-nitrogenous extracting molecules in the complexation of actinides (III) and lanthanides (III) in solution in anhydrous pyridine; Etude de la selectivite de molecules extractantes polyazotees dans la complexation des actinides (III) et des lanthanides (III) en solution dans la pyridine anhydre

    Energy Technology Data Exchange (ETDEWEB)

    Riviere, Ch

    2000-10-05

    The aim of this work is to better understand the factors which contribute to the separation of lanthanides(III) and actinides(III). Polydentate nitrogenous molecules present an interesting selectivity. A thermodynamic study of the complexation in pyridine of lanthanide and uranium by the bipyridine ligand (bipy) has been carried out. The formation constants and the thermodynamic values of the different complexes have been determined. It has been shown that the bipy complexes formation is controlled by the enthalpy and unfavored by the entropy. The conductometry has revealed too a significant difference in the uranium and lanthanides complexation by the bipyridine ligand. The use of the phenanthroline ligand induces a better complexation of the metallic ions but the selectivity is not improved. On the other hand, the decrease of the basicity and the increase of the ligand denticity (for instance in the case of the use of ter-pyridine) favour the selectivity without improving the complexation. The selectivity difference for the complexation of actinides(III) and lanthanides(III) by the different studied ligands (independent systems) has been confirmed by experiments of inter-metals competition. (O.M.)

  5. Silica nanoparticles doped with an iridium(III) complex for rapid and fluorometric detection of cyanide

    International Nuclear Information System (INIS)

    Mu, Juanjuan; Feng, Qingyue; Chen, Xiudan; Li, Jing; Wang, Huili; Li, Mei-Jin

    2015-01-01

    We describe a nanosensor for sensitive and selective detection of cyanide anions. The Ir(III) chlorine bridge complex [Ir(C N ) 2 -m-Cl] 2 (Irpq, where pq is C N = 2-phenyl quinoline) was doped into silica nanoparticles (SiNPs) with a typical size of about 30 nm. The intensity of the yellow emission of the doped SiNPs (under 410 nm exCitation) was strongly enhanced on addition of cyanide ions due to the replacement of chloride by cyanide. The method can detect cyanide ions in the 12.5 to 113 μM concentration range, and the limit of detection is 1.66 μM (at an S/N ratio of 3). The method is simple, sensitive and fast, and this makes it a candidate probe for the fast optical determination of cyanide. (author)

  6. Ethylene polymerization by PN3-type pincer chromium(III) complexes

    KAUST Repository

    Gong, Dirong; Liu, Wen; Chen, Tao; Chen, Zhongren; Huang, Kuo-Wei

    2014-01-01

    Chromium (III) complexes, Cr1, [2,6-(tBu2PNH) 2C5H4N]CrCl3; Cr2, [2,6-(Ph 2PNH)2C5H4N]CrCl3; Cr3, [2-(tBu2PNH)C5H4N]CrCl3 THF; Cr4, [6-(tBu2PNH)C5H4N-2- CH2NEt2]CrCl3; Cr5, [6-(tBu 2PNH)C5H4N-2-C3H2N 2]CrCl3; Cr6, [6-(tBu2PNH)C 5H4N-2-(3,5-Me2)C3H 2

  7. Organic iron (III) complexing ligands during an iron enrichment experiment in the western subarctic North Pacific

    Science.gov (United States)

    Kondo, Yoshiko; Takeda, Shigenobu; Nishioka, Jun; Obata, Hajime; Furuya, Ken; Johnson, William Keith; Wong, C. S.

    2008-06-01

    Complexation of iron (III) with natural organic ligands was investigated during a mesoscale iron enrichment experiment in the western subarctic North Pacific (SEEDS II). After the iron infusions, ligand concentrations increased rapidly with subsequent decreases. While the increases of ligands might have been partly influenced by amorphous iron colloids formation (12-29%), most in-situ increases were attributable to the Dilution of the fertilized patch may have contributed to the rapid decreases of the ligands. During the bloom decline, ligand concentration increased again, and the high concentrations persisted for 10 days. The conditional stability constant was not different between inside and outside of the fertilized patch. These results suggest that the chemical speciation of the released iron was strongly affected by formation of the ligands; the production of ligands observed during the bloom decline will strongly impact the iron cycle and bioavailability in the surface water.

  8. Mitochondria-targeting cyclometalated iridium(III)-PEG complexes with tunable photodynamic activity.

    Science.gov (United States)

    Li, Steve Po-Yam; Lau, Chris Tsan-Shing; Louie, Man-Wai; Lam, Yun-Wah; Cheng, Shuk Han; Lo, Kenneth Kam-Wing

    2013-10-01

    We present a new class of phosphorescent cyclometalated iridium(III) polypyridine poly(ethylene glycol) (PEG) complexes [Ir(N(^)C)2(bpy-CONH-PEG)](PF6) (bpy-CONH-PEG = 4-(N-(2-(ω-methoxypoly-(1-oxapropyl))ethyl)aminocarbonyl)-4'-methyl-2,2'-bipyridine, number average molecular weight (Mn) = 5272.23, weight average molecular weight (Mw) = 5317.38, polydispersity index (PDI) = 1.009; HN(^)C = 2-phenylpyridine, Hppy (1a), 2-((1,1'-biphenyl)-4-yl)pyridine, Hpppy (2a), 2-phenylquinoline, Hpq (3a), 2-phenylbenzothiazole, Hbt (4a), 2-(1-naphthyl)benzothiazole, Hbsn (5a)). The photophysical, photochemical, and biological properties of these complexes have been compared with those of their PEG-free counterparts [Ir(N(^)C)2(bpy-CONH-Et)](PF6) (bpy-CONH-Et = 4-(N-ethylaminocarbonyl)-4'-methyl-2,2'-bipyridine; HN(^)C = Hppy (1b), Hpppy (2b), Hpq (3b), Hbt (4b), Hbsn (5b)). Upon irradiation, all the complexes exhibited intense and long-lived green to orange-red emission under ambient conditions. The emission was phosphorescence in nature and can be quenched by O2 with the generation of singlet oxygen ((1)O2). The quantum yields for (1)O2 production of the complexes in aerated DMSO (0.24-0.83) were found to be dependent on the excited-state lifetimes of the complexes, which can be altered using different cyclometalating ligands (N(^)C). Cell-based assays indicated that the PEG complexes were noncytotoxic in the dark (IC50 > 300 μM); however, most of them became significantly cytotoxic upon irradiation (IC50 = 3.4 - 23.2 μM). Laser-scanning confocal microscopy images revealed localization of complex 3a in the mitochondrial region of HeLa cells and the induction of rapid necrotic cell death upon light activation. Additionally, the lack of dark toxicity and potential application of the PEG complexes as a visualizing reagent have been demonstrated using zebrafish (Danio rerio) as an animal model. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Radical-lanthanide ferromagnetic interaction in a T bIII bis-phthalocyaninato complex

    Science.gov (United States)

    Komijani, Dorsa; Ghirri, Alberto; Bonizzoni, Claudio; Klyatskaya, Svetlana; Moreno-Pineda, Eufemio; Ruben, Mario; Soncini, Alessandro; Affronte, Marco; Hill, Stephen

    2018-02-01

    Recent studies have highlighted the importance of organic ligands in the field of molecular spintronics, via which delocalized electron-spin density can mediate magnetic coupling to otherwise localized 4 f moments of lanthanide ions, which show tremendous potential for single-molecule device applications. To this end, high-field/high-frequency electron paramagnetic resonance (EPR) spectroscopy is employed to study a neutral terbium bis-phthalocyaninato metalorganic complex, [TbPc2 ] 0, with the aim of understanding the magnetic interaction between the Ising-like moment of the lanthanide ion and the unpaired spin density on the coordinating organic radical ligand. The measurements were performed on a previously unknown [TbPc2 ] 0 structural phase crystallizing in the Pnma space group. EPR measurements on powder samples of [TbPc2 ] 0 reveal an anisotropic spectrum, which is attributed to the spin-1/2 radical coupled weakly to the EPR-silent T bIII ion. Extensive double-axis rotation studies on a single crystal reveal two independent spin-1/2 signals with differently oriented (albeit identical) uniaxial g -tensors, in complete agreement with x-ray structural studies that indicate two molecular orientations within the unit cell. The easy-axis nature of the radical EPR spectra thus reflects the coupling to the Ising-like T bIII moment. This is corroborated by studies of the isostructural [YPc2 ] 0 analog (where Y is nonmagnetic yttrium), which gives a completely isotropic radical EPR signal. The experimental results for the terbium complex are well explained on the basis of an effective model that introduces a weak ferromagnetic Heisenberg coupling between an isotropic spin-1/2 and an anisotropic spin-orbital moment, J =6 , that mimics the known, strong easy-axis Tb ⋯P c2 crystal-field interaction.

  10. Zeolite-Y entrapped Ru(III and Fe(III complexes as heterogeneous catalysts for catalytic oxidation of cyclohexane reaction

    Directory of Open Access Journals (Sweden)

    Chetan K. Modi

    2017-02-01

    Full Text Available Catalysis is probably one of the greatest contributions of chemistry to both economic growth and environmental protection. Herein we report the catalytic behavior of zeolite-Y entrapped Ru(III and Fe(III complexes with general formulae [M(VTCH2·2H2O]+-Y and [M(VFCH2·2H2O]+-Y [where, VTCH = vanillin thiophene-2-carboxylic hydrazone and VFCH = vanillin furoic-2-carboxylic hydrazone] over the oxidation of cyclohexane forming cyclohexanone and cyclohexanol. The samples were corroborated by various physico-chemical techniques. These zeolite-Y based complexes are stable and recyclable under current reaction conditions. Amongst them, [Ru(VTCH2⋅2H2O]+-Y showed higher catalytic activity (41.1% with cyclohexanone (84.6% selectivity.

  11. Synthesis and characterization of europium aluminophosphate

    International Nuclear Information System (INIS)

    Araujo, A.S.; Diniz, J.C.; Silva, A.O.S.

    1998-01-01

    Full text: Aluminophosphate molecular sieves (ALPO) represents a class of materials formed by AlO 2+ and PO 2- tetrahedra linked together through b the oxygen atom. The incorporation of metal cations, specifically rare earths, in the ALPO matrix, gives rise to generation of new materials that can be used as acid catalysts in chemical processes. In this work, it was synthesized hydrothermally a molecular sieve type Eu-ALPO-11, starting from an hydrated alumina (pseudobohemite), phosphoric acid solution, europium chloride, water, and di-isopropylamine (DIPA) as organic template. The gel of synthesis presented the following composition: 1.0 DIPA: 0.05 Eu 2 O 3 :0.95 Al 2 O 3 : 1.0 P 2 O 5 : 80 H 2 O The hydrogel was autoclaved at 170 deg C for a period of 3 days. After that the obtained solid was filtered, washed, dried and calcined at 500 deg C to remove the template. The sample was characterized by several physico-chemical methods, such a atomic absorption, FT-IR spectroscopy, X-ray diffraction, thermal analysis, scanning electron microscopy. Its spectroscopic properties was investigated by europium luminescence. The physico-chemical characterization of the Eu-ALPO-11 showed very good crystallinity, with AEL structure, and orthorhombic symmetry. Also, the material presents excellent thermal stability, with no structural collapse until 950 deg C. Through the luminescence spectra in the visible region, it was observed that the emission of the Eu 3+ is strongly influenced by the increasing of the 5d0 7f0 transition (Electric Dipole), as compared to the 5d0 7f1 transition (Magnetic Dipole) between the levels of 4f configuration perturbed by the crystalline field. The ED/MD ratio to the as synthesized sample was ca. 2.1, against ca. 1.1 relative to the calcined sample. The FT-IR spectra presented well defined absorption bands relative to Al-O and P-O bonds, of the structural internal tetrahedra (IT) and external links (EL): 1250- 950 cm -1 , symmetric stretching due to

  12. Assembly and stoichiometry of the core structure of the bacterial flagellar type III export gate complex.

    Science.gov (United States)

    Fukumura, Takuma; Makino, Fumiaki; Dietsche, Tobias; Kinoshita, Miki; Kato, Takayuki; Wagner, Samuel; Namba, Keiichi; Imada, Katsumi; Minamino, Tohru

    2017-08-01

    The bacterial flagellar type III export apparatus, which is required for flagellar assembly beyond the cell membranes, consists of a transmembrane export gate complex and a cytoplasmic ATPase complex. FlhA, FlhB, FliP, FliQ, and FliR form the gate complex inside the basal body MS ring, although FliO is required for efficient export gate formation in Salmonella enterica. However, it remains unknown how they form the gate complex. Here we report that FliP forms a homohexameric ring with a diameter of 10 nm. Alanine substitutions of conserved Phe-137, Phe-150, and Glu-178 residues in the periplasmic domain of FliP (FliPP) inhibited FliP6 ring formation, suppressing flagellar protein export. FliO formed a 5-nm ring structure with 3 clamp-like structures that bind to the FliP6 ring. The crystal structure of FliPP derived from Thermotoga maritia, and structure-based photo-crosslinking experiments revealed that Phe-150 and Ser-156 of FliPP are involved in the FliP-FliP interactions and that Phe-150, Arg-152, Ser-156, and Pro-158 are responsible for the FliP-FliO interactions. Overexpression of FliP restored motility of a ∆fliO mutant to the wild-type level, suggesting that the FliP6 ring is a functional unit in the export gate complex and that FliO is not part of the final gate structure. Copurification assays revealed that FlhA, FlhB, FliQ, and FliR are associated with the FliO/FliP complex. We propose that the assembly of the export gate complex begins with FliP6 ring formation with the help of the FliO scaffold, followed by FliQ, FliR, and FlhB and finally FlhA during MS ring formation.

  13. Preparation and spectral properties of europium hydrogen squarate microcrystals

    Science.gov (United States)

    Kolev, T.; Danchova, N.; Shandurkov, D.; Gutzov, S.

    2018-04-01

    A simple scheme for preparation of europium hydrogen squarate octahydrate microcrystals, Eu(HSq)3·8H2O is demonstrated. The microcrystalline powders obtained have a potential application as non-centrosymmetric and UV radiation - protective hybrid optical material. The site-symmetry of the Eu - ion is C2V or lower, obtained from diffuse reflectance spectra. The formation of europium hydrogen squarate is supported by IR - spectroscopy, UV-vis spectroscopy, chemical analysis and X-ray diffraction. A detailed analysis of the UV-vis and IR spectra of the micropowders prepared is presented. The reaction between europium oxide and squaric acid leads to formation of microcrystalline plate-like crystals of europium hydrogen squarate Eu(HSq)3·8H2O, a non-centrosymmetric hybrid optical material with a potential application as UV radiation - protective coatings.

  14. Synthesis, spectral characterization and in vitro antifungal activity of Lanthanum(III) and Praseodymium(III) complexes with Schiff bases derived from 5-substituted-4-amino-5-hydrazino-1,2,4-triazoles and isatin

    International Nuclear Information System (INIS)

    Singh, Shweta; Tripathi, Priti; Pandey, Om P.; Sengupta, Soumitra K.

    2013-01-01

    The new lanthanum(III) and praseodymium(III) complexes of the general formula (LnCl(L)(H 2 O) 2 ) (Ln = La III or Pr III ; H 2 L = Schiff bases derived from 3-substituted-4-amino-5-hydrazino-1,2,4-triazoles and isatin) have been prepared. The complexes have been characterized by elemental analyses, molecular weight by FAB-mass, thermogravimetry, electrical conductance, magnetic moment and spectral (electronic, infrared, far-infrared, 1 H NMR and 13 C NMR) data. The ligands and all prepared complexes were assayed for antifungal (Aspergillus niger and Helminthosporium oryzae) activities. The activities have been correlated with the structures of the complexes. (author)

  15. Moessbauer spectroscopic evidence for iron(III) complexation and reduction in acidic aqueous solutions of indole-3-butyric acid

    International Nuclear Information System (INIS)

    Kovacs, K.; Kuzmann, E.; Vertes, A.; Kamnev, A.A.; Shchelochkov, A.G.; Medzihradszky-Schweiger, H.; Mink, J.; Hungarian Academy of Sciences, Budapest

    2004-01-01

    Moessbauer spectroscopic studies were carried out in acidic (pH 2.3) 57 Fe III nitrate containing aqueous solutions of indole-3-butyric acid (IBA), rapidly frozen in liquid nitrogen at various periods of time after mixing the reagents. The data obtained show that in solution in the presence of IBA, iron(III) forms a complex with a dimeric structure characterised by a quadrupole doublet, whereas without IBA under similar conditions iron(III) exhibits a broad spectral feature due to a slow paramagnetic spin relaxation which, at liquid nitrogen temperature, results in a large anomalous line broadening (or, at T = 4.2 K, in a hyperfine magnetic splitting). The spectra of 57 Fe III +IBA solutions, kept at ambient temperature under aerobic conditions for increasing periods of time before freezing, contained a gradually increasing contribution of a component with a higher quadrupole splitting. The Moessbauer parameters for that component are typical for iron(II) aquo complexes, thus showing that under these conditions gradual reduction of iron(III) occurs, so that the majority (85%) of dissolved iron(III) is reduced within 2 days. The Moessbauer parameters for the iron(III)-IBA complex in aqueous solution and in the solid state (separated from the solution by filtration) were found to be similar, which may indicate that the dissolved and solid complexes have the same composition and/or iron(III) coordination environment. For the solid complex, the data of elemental analysis suggest the following composition of the dimer: [L 2 Fe-(OH) 2 -FeL 2 ] (where L is indole-3-butyrate). This structure is also in agreement with the data of infrared spectroscopic study of the complex reported earlier, with the side-chain carboxylic group in indole-3-butyrate as a bidentate ligand. The Moessbauer parameters for the solid 57 Fe III -IBA complex at T = 80 K and its acetone solution rapidly frozen in liquid nitrogen were virtually identical, which indicates that the complex retains its

  16. Study of the interactions between Eu(III) and Al2O3 particles in the presence of phenolic acids

    International Nuclear Information System (INIS)

    Moreau, P.

    2012-01-01

    In the framework of environmental pollution by radionuclides, this work was focused on the interactions occurring in systems containing europium(III) - as a chemical analogue for the actinides Am(III) and Cm(III) -, phenolic acids - lignin degradation products and anti-fungi, naturally occurring in soils, and alumina - representative of sorption sites found in the environment. This study was conducted at different scales of description: the macroscopic scale - to quantify Eu(III) and/or phenolic acids adsorption onto the mineral surface -, and the microscopic scale - to study the chemical environment of Eu(III) using Time-Resolved Luminescence Spectroscopy (TRLS). First, the binary systems, i.e. systems containing only two entities among the three previously cited, were characterized. Complexation constants of Eu(III) by three phenolic acids (4-hydroxybenzoic, 3,4-dihydroxybenzoic, and 3,4,5-trihydroxybenzoic acids) were determined and quantum calculations (DFT) were carried out on La(III)-acid complex analogues. Sorption of the acids onto aluminol sites was modelled using surface complexation concepts. Analyses of two ternary systems (containing 4-hydroxybenzoic and 3,4-dihydroxybenzoic acids) revealed synergistic processes for Eu(III) and phenolic acids sorption onto Al 2 O 3 . A spectral fingerprint of ternary complex involving Eu(III)/4-hydroxybenzoic acid/Al 2 O 3 surface sites was evidenced. (author) [fr

  17. Electrochemical Study of the EuIII/EuII Redox Properties of Complexes with Potential MRI Ligands

    Czech Academy of Sciences Publication Activity Database

    Gál, Miroslav; Kielar, F.; Sokolová, Romana; Ramešová, Šárka; Kolivoška, Viliam

    2013-01-01

    Roč. 2013, č. 18 (2013), s. 3217-3223 ISSN 1434-1948 R&D Projects: GA ČR GA203/09/1607 Institutional support: RVO:61388955 Keywords : europium * cyclic voltammetry * nitrogen heterocycle Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.965, year: 2013

  18. Crystal structures and Moessbauer spectra of spin-crossover iron(III) complexes of quinquedentate ligands

    International Nuclear Information System (INIS)

    Maeda, Yonezo; Noda, Yosuke; Oshio, Hiroki; Takashima, Yoshimasa; Matsumoto, Naohide

    1994-01-01

    Magnetic properties, Moessbauer spectra and crystal structures of spin-crossover iron(III) complexes with a quinquedentate ligand [FeLX]BPh 4 are reported. X and L denote a unidentate ligand and a quinquedentate ligand, respectively. [Fe(mbpN)(im)]BPh 4 shows spin-crossover behavior in an appropriate organic solvent, and [Fe(mbpN)(lut)]BPh 4 , [Fe(bpN)(py)]BPh 4 and [Fe(salten)X]BPh 4 (X = 4me-py or 2me-im) show spin-crossover behavior in a solid and in an organic solvent. It was found that the ligand field strength of salten was stronger than that of mbpN. The rates of spin-state interexchange in the complexes are as fast as the inverse of the lifetime (1 x 10 -7 s) of the Moessbauer nuclear level. The Moessbauer spectroscopic behavior of [Fe(mbpN)(lut)]BPh 4 and [Fe(bpN)(py)]BPh 4 is different to that of [Fe(salten)X]BPh 4 (X = 4me-py or 2me-im). The difference was ascribed to the different geometrical positions of the corresponding anions. (orig.)

  19. Efficient catalytic cycloalkane oxidation employing a "helmet" phthalocyaninato iron(III) complex.

    Science.gov (United States)

    Brown, Elizabeth S; Robinson, Jerome R; McCoy, Aaron M; McGaff, Robert W

    2011-06-14

    We have examined the catalytic activity of an iron(III) complex bearing the 14,28-[1,3-diiminoisoindolinato]phthalocyaninato (diiPc) ligand in oxidation reactions with three substrates (cyclohexane, cyclooctane, and indan). This modified metallophthalocyaninato complex serves as an efficient and selective catalyst for the oxidation of cyclohexane and cyclooctane, and to a far lesser extent indan. In the oxidations of cyclohexane and cyclooctane, in which hydrogen peroxide is employed as the oxidant under inert atmosphere, we have observed turnover numbers of 100.9 and 122.2 for cyclohexanol and cyclooctanol, respectively. The catalyst shows strong selectivity for alcohol (vs. ketone) formation, with alcohol to ketone (A/K) ratios of 6.7 and 21.0 for the cyclohexane and cyclooctane oxidations, respectively. Overall yields (alcohol + ketone) were 73% for cyclohexane and 92% for cyclooctane, based upon the total hydrogen peroxide added. In the catalytic oxidation of indan under similar conditions, the TON for 1-indanol was 10.1, with a yield of 12% based upon hydrogen peroxide. No 1-indanone was observed in the product mixture.

  20. New cyclometalated iridium(III) complex as a phosphorescent dopant in organic light emitting devices

    Science.gov (United States)

    Ivanov, P.; Tomova, R.; Petrova, P.; Stanimirov, S.; Petkov, I.

    2014-05-01

    A new cyclometalated iridium (III) bis[2-(4-chlorophenyl)benzothiazolato-N,C2]-acetylacetonate, (Cl-bt)2Ir(acac), was synthesized and identified by 1H NMR and elemental analysis. The application was studied of the new compound as a dopant in the hole transporting layer (HTL) of the following organic light emitting diode (OLED) structure: HTL/EL/ETL, where HTL was 4,4'-bis(9H-carbazol-9-yl)biphenyl (CBP) or N,N'-bis(3-methylphenyl)-N,N'-diphenylbenzidine (TPD), incorporated in a poly(N-vinylcarbazole) (PVK) matrix; EL was an electroluminescent layer of bis(8-hydroxy-2-methylquinoline)-(4-phenylpheno-xy) aluminum (BAlq); and ETL was an electron-transporting layer of bis[2-(2-benzothiazoly) phenolato]zinc(II) (Zn(btz)2). We established that the electroluminescence spectra of the OLEDs at different dopant concentrations were basically the sum of the greenish-blue emission of BAlq and the yellowish-green emission of the Ir complex. It was also found that increasing the dopant concentration resulted in an increase in the relative electroluminescent intensity of the Ir complex emission, while that of BAlq decreased, thus a fine tuning of the OLED color was observed.

  1. Synthesis and photophysical studies of blue phosphorescent Ir(III) complexes with dimethylphenylphospine.

    Science.gov (United States)

    Ham, Ho-Wan; Jung, Kyung-Yoon; Kim, Young-Sik

    2012-02-01

    New blue emitting mixed ligand iridium(III) complexes comprising one cyclometalating, two phosphines trans to each other such as Ir{(CF3)2Meppy}(PPhMe3)2(H)(L) [L = CI, NCMe, CN] [(CF3)2Meppy = 2-(3', 5'-bis-trifluoromethylphenyl)-4-methylpyridine] were synthesized and studied to tune the phosphorescence wavelength to the deep blue region and to enhance the luminescence efficiencies. To achieve deep blue emission, the trifluoromethyl group substituted on the phenyl ring and the methyl group substituted on the pyridyl ring increased HOMO-LUMO gap and achieved the hypsochromic shift. To gain insight into the factors responsible for the emission color change and the different luminescence efficiency, we investigate the electron-withdrawing capabilities of ancillary ligands using the DFT and TD-DFT calculations on the ground and excited states of the complexes. From these results, we discuss how the ancillary ligand influences the emission peak as well as the metal to ligand charge transfer (MLCT) transition efficiency. The maximum emission spectra of Ir{(CF3)2Meppy}(PPhMe3)2(H)(Cl), [Ir{(CF3),Meppy)(PPhMe3),(H)(NCMe)]+ and Ir{(CF3)2Meppy}(PPhMe3)2(H)(CN) were in the ranges of 441, 435, 434 nm, respectively.

  2. Electronic structure and superconductivity of europium

    International Nuclear Information System (INIS)

    Nixon, Lane W.; Papaconstantopoulos, D.A.

    2010-01-01

    We have calculated the electronic structure of Eu for the bcc, hcp, and fcc crystal structures for volumes near equilibrium up to a calculated 90 GPa pressure using the augmented-plane-wave method in the local-density approximation. The frozen-core approximation was used with a semi-empirical shift of the f-states energies in the radial Schroedinger equation to move the occupied 4f valence states below the Γ 1 energy and into the core. This shift of the highly localized f-states yields the correct europium phase ordering with lattice parameters and bulk moduli in good agreement with experimental data. The calculated superconductivity properties under pressure for the bcc and hcp structures are also found to agree with and follow a T c trend similar to recent measurement by Debessai et al.

  3. Preparation of 99mTc-thiourea complex as a precursor for Tc(III) labeled compounds

    International Nuclear Information System (INIS)

    Rey, A.; Teran, M.; Molina, S.; Leon, A.; Kremer, C.; Gambino, D.; Kremer, E.

    1996-01-01

    Ligand exchange is one of the possible synthetic routes to obtain 99m Tc coordination compounds. However, the success of this route depends on the availability of good precursors. The objective of this work is the preparation of the complex [ 99m Tc (tu) 6 ] 3+ (tu = thiourea), as a potential precursor for 99m Tc(III) coordination compounds. The preparation was successfully performed in acidic conditions, the excess of tu serving as reducing agent. At pH values higher than 3, the compound becomes unstable and on addition of polydentate ligands new Tc(III) complexes are formed. With edta, the complex 99m Tc(III)-edta was obtained in high yield. (author). 13 refs., 3 tabs

  4. Electro-spray Ionization Mass Spectrometry Investigation of BTBP - Lanthanide(III) and Actinide(III) Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Retegan, T.; Ekberg, Ch. [Chalmers, Dept Chem and Biol Engn, SE-41296 Gothenburg, (Sweden); Berthon, L.; Zorz, N. [DEN DRCP SCPS LCSE, CEA Marcoule, Bagnols Sur Ceze, (France)

    2009-07-01

    In the framework of nuclear waste reprocessing, the separation processes of minor actinides from fission products are developed using liquid-liquid extraction. To gain an understanding of the mechanism involved in the extraction process, a complex formation of actinides and lanthanides with BTBPs (6, 6'-bis(5, 6-dialkyl-1, 2, 4-triazin-3-yl)-2, 2'-bipyridines) was characterized using the Electro-spray Ionization Mass Spectrometry (ESI-MS) technique. This study was carried out to compare the influence of diluents and side groups of the extractants on complex formation. Three different diluents, nitrobenzene, octanol and cyclohexanone, and two extractants, C5-BTBP and CyMe{sub 4}-BTBP, were selected for this experiment. It was found that the change of the diluent and of the substituent on the BTBP moiety does not modify the stoichiometry of the complexes which is L{sub 2}M(NO{sub 3}){sub 3}. It is proposed that one nitrate is directly coordinated to the metal ion, the two other anions probably remaining in the outer coordination sphere. The difference observed in extracting properties is probably due to the solvation of the complexes by the diluent. The noncovalent force that holds complexes together are likely to be largely governed by electrostatic interactions even if the hydrophobic exterior of the complexes plays an important role in the complexation/extraction mechanism. The study of the stability of the ions in the gas phase shows that the C5-BTBP ligand has a labile hydrogen atom, which is a fragility point of C5-BTBP. (authors)

  5. Regulation of the Tumor-Suppressor Function of the Class III Phosphatidylinositol 3-Kinase Complex by Ubiquitin and SUMO

    Energy Technology Data Exchange (ETDEWEB)

    Reidick, Christina [Biochemie Intrazellulärer Transportprozesse, Ruhr-Universität Bochum, Bochum 44801 (Germany); El Magraoui, Fouzi; Meyer, Helmut E. [Biomedical Research, Human Brain Proteomics II, Leibniz-Institut für Analytische Wissenschaften-ISAS, Dortmund 44139 (Germany); Stenmark, Harald [Department of Biochemistry, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo 0310 (Norway); Platta, Harald W., E-mail: harald.platta@rub.de [Biochemie Intrazellulärer Transportprozesse, Ruhr-Universität Bochum, Bochum 44801 (Germany)

    2014-12-23

    The occurrence of cancer is often associated with a dysfunction in one of the three central membrane-involution processes—autophagy, endocytosis or cytokinesis. Interestingly, all three pathways are controlled by the same central signaling module: the class III phosphatidylinositol 3-kinase (PI3K-III) complex and its catalytic product, the phosphorylated lipid phosphatidylinositol 3-phosphate (PtdIns3P). The activity of the catalytic subunit of the PI3K-III complex, the lipid-kinase VPS34, requires the presence of the membrane-targeting factor VPS15 as well as the adaptor protein Beclin 1. Furthermore, a growing list of regulatory proteins associates with VPS34 via Beclin 1. These accessory factors define distinct subunit compositions and thereby guide the PI3K-III complex to its different cellular and physiological roles. Here we discuss the regulation of the PI3K-III complex components by ubiquitination and SUMOylation. Especially Beclin 1 has emerged as a highly regulated protein, which can be modified with Lys11-, Lys48- or Lys63-linked polyubiquitin chains catalyzed by distinct E3 ligases from the RING-, HECT-, RBR- or Cullin-type. We also point out other cross-links of these ligases with autophagy in order to discuss how these data might be merged into a general concept.

  6. Regulation of the Tumor-Suppressor Function of the Class III Phosphatidylinositol 3-Kinase Complex by Ubiquitin and SUMO

    International Nuclear Information System (INIS)

    Reidick, Christina; El Magraoui, Fouzi; Meyer, Helmut E.; Stenmark, Harald; Platta, Harald W.

    2014-01-01

    The occurrence of cancer is often associated with a dysfunction in one of the three central membrane-involution processes—autophagy, endocytosis or cytokinesis. Interestingly, all three pathways are controlled by the same central signaling module: the class III phosphatidylinositol 3-kinase (PI3K-III) complex and its catalytic product, the phosphorylated lipid phosphatidylinositol 3-phosphate (PtdIns3P). The activity of the catalytic subunit of the PI3K-III complex, the lipid-kinase VPS34, requires the presence of the membrane-targeting factor VPS15 as well as the adaptor protein Beclin 1. Furthermore, a growing list of regulatory proteins associates with VPS34 via Beclin 1. These accessory factors define distinct subunit compositions and thereby guide the PI3K-III complex to its different cellular and physiological roles. Here we discuss the regulation of the PI3K-III complex components by ubiquitination and SUMOylation. Especially Beclin 1 has emerged as a highly regulated protein, which can be modified with Lys11-, Lys48- or Lys63-linked polyubiquitin chains catalyzed by distinct E3 ligases from the RING-, HECT-, RBR- or Cullin-type. We also point out other cross-links of these ligases with autophagy in order to discuss how these data might be merged into a general concept

  7. 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)

  8. Synthesis, Photoluminescence Behavior of Green Light Emitting Tb(III) Complexes and Mechanistic Investigation of Energy Transfer Process.

    Science.gov (United States)

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

    2018-06-04

    A series of five new terbium(III) ion complexes with 4,4-difluoro-1-phenylbutane-1,3-dione (HDPBD) and anciliary ligands was synthesized. The composition and properties of complexes were analyzed by elemental analysis, IR, NMR, powder X-ray diffaraction, TG-DTG and photoluminescence spectroscopy. These complexes exhibited ligand sensitized green emission at 546 nm associated with 5 D 4  →  7 F 5 transitions of terbium ion in the emission spectra. The photoluminescence study manifested that the organic ligands act as antenna and facilitate the absorbed energy to emitting levels of Tb(III) ion efficiently. The enhanced luminescence intensity and decay time of ternary C2-C5 complexes observed due to synergistic effect of anciliary ligands. The CIE color coordinates of complexes came under the green region of chromaticity diagram. The mechanistic investigation of intramolecular energy transfer in the complexes was discussed in detail. These terbium(III) complexes can be thrivingly used as one of the green component in light emitting material and in display devices. Graphical Abstract Illustrate the sensitization process of the Tb ion and intramolecular energy transfer process in the Tb 3+ complex.

  9. Self-assembly in lanthanum(III) and calcium(II) complexes of salicylaldimines derived from putrescine

    International Nuclear Information System (INIS)

    Pospieszna-Markiewicz, Izabela; Kaczmarek, Malgorzata T.; Kubicki, Maciej; Radecka-Paryzek, Wanda

    2008-01-01

    The one-step template reaction of salicylaldehyde with putrescine, a biogenic diamine, in the presence of lanthanum(III) or calcium(II) ions produces salicylaldimine complexes containing the N,N'-bis(salicylidene)-1,4-butanediamine ligand L as a result of the [2 + 1] Schiff base condensation. The X-ray diffraction studies of the lanthanum complex reveals an infinite [La 2 L 4 (NO 3 ) 6 ] ∞ polymeric structure based on networks of 10-coordinated La(III) nodes linked by bridging unionized ligands that use exclusively the oxygens as donor atoms with the nitrogen atoms not being involved in coordination

  10. Carbon-13 magnetic relaxation rates or iron (III) complexes of some biogenic amines and parent compounds in aqueous solutions

    International Nuclear Information System (INIS)

    Lai, A.; Monduzzi, M.; Saba, G.

    1980-01-01

    Spin-lattice relaxation rates (R 1 ) from naturally occuring C-13 F.T. N.M.R. spectra of some catecholamines and parent compounds with Iron(III) at pD = 4 were determined in order to elucidate the molecular mechanism underlying their association in aqueous solutions. Complexation was observed only for catecholic ligands. The R 1 values were used to calculate iron-carbon scaled distances, and two complexation models were proposed where the catecholic function binds Fe(III) in the first and second coordination spheres respectively. The latter case was shown to be the consistent with the molecular geometries. (orig.)

  11. A colorimetric and luminescent dual-modal assay for Cu(II ion detection using an iridium(III complex.

    Directory of Open Access Journals (Sweden)

    Dik-Lung Ma

    Full Text Available A novel iridium(III complex-based chemosensor bearing the 5,6-bis(salicylideneimino-1,10-phenanthroline ligand receptor was developed, which exhibited a highly sensitive and selective color change from colorless to yellow and a visible turn-off luminescence response upon the addition of Cu(II ions. The interactions of this iridium(III complex with Cu2+ ions and thirteen other cations have been investigated by UV-Vis absorption titration, emission titration, and 1H NMR titration.

  12. Lanthanide(III) complexes of bis-semicarbazone and bis-imine-substituted phenanthroline ligands: solid-state structures, photophysical properties, and anion sensing.

    Science.gov (United States)

    Nadella, Sandeep; Selvakumar, Paulraj M; Suresh, Eringathodi; Subramanian, Palani S; Albrecht, Markus; Giese, Michael; Fröhlich, Roland

    2012-12-21

    Phenanthroline-based hexadentate ligands L(1) and L(2) bearing two achiral semicarbazone or two chiral imine moieties as well as the respective mononuclear complexes incorporating various lanthanide ions, such as La(III), Eu(III), Tb(III), Lu(III), and Y(III) metal ions, were synthesized, and the crystal structures of [ML(1)Cl(3)] (M=La(III), Eu(III), Tb(III), Lu(III), or Y(III)) complexes were determined. Solvent or water molecules act as coligands for the rare-earth metals in addition to halide anions. The big Ln(III) ion exhibits a coordination number (CN) of 10, whereas the corresponding Eu(III), Tb(III), Lu(III), and Y(III) centers with smaller ionic radii show CN=9. Complexes of L(2), namely [ML(2)Cl(3)] (M=Eu(III), Tb(III), Lu(III), or Y(III)) ions could also be prepared. Only the complex of Eu(III) showed red luminescence, whereas all the others were nonluminescent. The emission properties of the Eu derivative can be applied as a photophysical signal for sensing various anions. The addition of phosphate anions leads to a unique change in the luminescence behavior. As a case study, the quenching behavior of adenosine-5'-triphosphate (ATP) was investigated at physiological pH value in an aqueous solvent. A specificity of the sensor for ATP relative to adenosine-5'-diphosphate (ADP) and adenosine-5'-monophosphate (AMP) was found. (31)P NMR spectroscopic studies revealed the formation of a [EuL(2)(ATP)] coordination species. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Separation of Am(III) from Eu(III) by mixtures of triazynylbipyridine and bis(dicarbollide) extractants. The composition of the metal complexes extracted

    International Nuclear Information System (INIS)

    Narbutt, J.; Krejzler, J.

    2006-01-01

    Separation of trivalent actinides, in particular americium and curium, from lanthanides is an important step in an advanced partitioning process for future reprocessing of spent nuclear fuels. The use of soft donor (N and S) ligands makes it possible to separate the two groups of elements, probably because of the more covalent character in the complexes with actinides compared to the lanthanides. The aim of present work was to study solvent extraction of Am(III) and Eu(III) in a similar system with diethylhemi-BTP and COSAN: protonated bis(chlorodicarbollido)cobalt(III) or commo-3,3-cobalta-bis(8,9,12-trichlora-1,2-dicarbaclosododecaborane)ic acid. The present research was focused on both the determination of conditions for the separation of 241 Am(III) from 152 Eu in aqueous nitrate solution by using a synergistic extraction system and on the modelling of the process by slope analysis. Obtained values of the separation factors supported by the computer modelling permitted drawing the conclusions on the mechanism of the process and on the structure of extracted species

  14. Synthesis of novel '4+1' Tc(III)/Re(III) mixed-ligand complexes with dendritically modified ligands

    International Nuclear Information System (INIS)

    Gniazdowska, E.; Kuenstler, J.U.; Stephan, H.; Pietzsch, H.J.

    2006-01-01

    Coordination chemistry of technetium and rhenium attracts a considerable interest due to the nuclear medicine applications of their radionuclides. Inert, so-called '3+1' or '4+1' technetium/rhenium mixed-ligand complexes open a new way to application of 99 mTc/ 188 Re labeled compounds in tumor diagnosis and therapy. In the presented paper, authors describe the synthesis and study of novel 99 mTc/ 188 Re complexes with dendritically functionalized tetradentate (tripodal chelator 2,2',2''-nitrilotris(ethanethiol), NS 3 and carboxyl group-bearing ligand, NS 3 (COOH) 3 ) and monodentate (dendritically modified isocyanide, CN-R(COOMe) 3 and isocyanide-modified peptide, CN-GGY) ligands. To verify the identity of the prepared n.c.a. complexes, non-radioactive analogous '4+1' Re compounds were synthesized. The experimental data show that a dendritic modification of the tetradentate/monodentate ligands changes the complex lipophilicity and does not influence its stability

  15. Synthesis, structure, luminescent, and magnetic properties of carbonato-bridged Zn(II)2Ln(III)2 complexes [(μ4-CO3)2{Zn(II)L(n)Ln(III)(NO3)}2] (Ln(III) = Gd(III), Tb(III), Dy(III); L(1) = N,N'-bis(3-methoxy-2-oxybenzylidene)-1,3-propanediaminato, L(2) = N,N'-bis(3-ethoxy-2-oxybenzylidene)-1,3-propanediaminato).

    Science.gov (United States)

    Ehama, Kiyomi; Ohmichi, Yusuke; Sakamoto, Soichiro; Fujinami, Takeshi; Matsumoto, Naohide; Mochida, Naotaka; Ishida, Takayuki; Sunatsuki, Yukinari; Tsuchimoto, Masanobu; Re, Nazzareno

    2013-11-04

    Carbonato-bridged Zn(II)2Ln(III)2 complexes [(μ4-CO3)2{Zn(II)L(n)Ln(III)(NO3)}2]·solvent were synthesized through atmospheric CO2 fixation reaction of [Zn(II)L(n)(H2O)2]·xH2O, Ln(III)(NO3)3·6H2O, and triethylamine, where Ln(III) = Gd(III), Tb(III), Dy(III); L(1) = N,N'-bis(3-methoxy-2-oxybenzylidene)-1,3-propanediaminato, L(2) = N,N'-bis(3-ethoxy-2-oxybenzylidene)-1,3-propanediaminato. Each Zn(II)2Ln(III)2 structure possessing an inversion center can be described as two di-μ-phenoxo-bridged {Zn(II)L(n)Ln(III)(NO3)} binuclear units bridged by two carbonato CO3(2-) ions. The Zn(II) ion has square pyramidal coordination geometry with N2O2 donor atoms of L(n) and one oxygen atom of a bridging carbonato ion at the axial site. Ln(III) ion is coordinated by nine oxygen atoms consisting of four from the deprotonated Schiff-base L(n), two from a chelating nitrate, and three from two carbonate groups. The temperature-dependent magnetic susceptibilities in the range 1.9-300 K, field-dependent magnetization from 0 to 5 T at 1.9 K, and alternating current magnetic susceptibilities under the direct current bias fields of 0 and 1000 Oe were measured. The magnetic properties of the Zn(II)2Ln(III)2 complexes are analyzed on the basis of the dicarbonato-bridged binuclear Ln(III)-Ln(III) structure, as the Zn(II) ion with d(10) electronic configuration is diamagnetic. ZnGd1 (L(1)) and ZnGd2 (L(2)) show a ferromagnetic Gd(III)-Gd(III) interaction with J(Gd-Gd) = +0.042 and +0.028 cm(-1), respectively, on the basis of the Hamiltonian H = -2J(Gd-Gd)ŜGd1·ŜGd2. The magnetic data of the Zn(II)2Ln(III)2 complexes (Ln(III) = Tb(III), Dy(III)) were analyzed by a spin Hamiltonian including the crystal field effect on the Ln(III) ions and the Ln(III)-Ln(III) magnetic interaction. The Stark splitting of the ground state was so evaluated, and the energy pattern indicates a strong easy axis (Ising type) anisotropy. Luminescence spectra of Zn(II)2Tb(III)2 complexes were observed, while those

  16. Biochemical investigation of yttrium(III) complex containing 1,10-phenanthroline: DNA binding and antibacterial activity.

    Science.gov (United States)

    Khorasani-Motlagh, Mozhgan; Noroozifar, Meissam; Moodi, Asieh; Niroomand, Sona

    2013-03-05

    Characterization of the interaction between yttrium(III) complex containing 1,10-phenanthroline as ligand, [Y(phen)2Cl(OH2)3]Cl2⋅H2O, and DNA has been carried out by UV absorption, fluorescence spectra and viscosity measurements in order to investigate binding mode. The experimental results indicate that the yttrium(III) complex binds to DNA and absorption is decreasing in charge transfer band with the increase in amount of DNA. The binding constant (Kb) at different temperatures as well as thermodynamic parameters, enthalpy change (ΔH°) and entropy change (ΔS°), were calculated according to relevant fluorescent data and Vant' Hoff equation. The results of interaction mechanism studies, suggested that groove binding plays a major role in the binding of the complex and DNA. The activity of yttrium(III) complex against some bacteria was tested and antimicrobial screening tests shown growth inhibitory activity in the presence of yttrium(III) complex. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. A study of the Fe(III)/Fe(II)-triethanolamine complex redox couple for redox flow battery application

    International Nuclear Information System (INIS)

    Wen, Y.H.; Zhang, H.M.; Qian, P.; Zhou, H.T.; Zhao, P.; Yi, B.L.; Yang, Y.S.

    2006-01-01

    The electrochemical behavior of the Fe(III)/Fe(II)-triethanolamine(TEA) complex redox couple in alkaline medium and influence of the concentration of TEA were investigated. A change of the concentration of TEA mainly produces the following two results. (1) With an increase of the concentration of TEA, the solubility of the Fe(III)-TEA can be increased to 0.6 M, and the solubility of the Fe(II)-TEA is up to 0.4 M. (2) In high concentration of TEA with the ratio of TEA to NaOH ranging from 1 to 6, side reaction peaks on the cathodic main reaction of the Fe(III)-TEA complex at low scan rate can be minimized. The electrode process of Fe(III)-TEA/Fe(II)-TEA is electrochemically reversible with higher reaction rate constant than the uncomplexed species. Constant current charge-discharge shows that applying anodic active materials of relatively high concentrations facilitates the improvement of cell performance. The open-circuit voltage of the Fe-TEA/Br 2 cell with the Fe(III)-TEA of 0.4 M, after full charging, is nearly 2.0 V and is about 32% higher than that of the all-vanadium batteries, together with the energy efficiency of approximately 70%. The preliminary exploration shows that the Fe(III)-TEA/Fe(II)-TEA couple is electrochemically promising as negative redox couple for redox flow battery (RFB) application

  18. 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.

  19. Concomitant carboxylate and oxalate formation from the activation of CO{sub 2} by a thorium(III) complex

    Energy Technology Data Exchange (ETDEWEB)

    Formanuik, Alasdair; Ortu, Fabrizio; Mills, David P. [School of Chemistry, The University of Manchester (United Kingdom); Inman, Christopher J. [Department of Chemistry and Biochemistry, School of Life Sciences, University of Sussex, Brighton (United Kingdom); Kerridge, Andrew [Department of Chemistry, Lancaster University (United Kingdom); Castro, Ludovic; Maron, Laurent [LPCNO, CNRA et INSA, Universite Paul Sabatier, Toulouse (France)

    2016-12-12

    Improving our comprehension of diverse CO{sub 2} activation pathways is of vital importance for the widespread future utilization of this abundant greenhouse gas. CO{sub 2} activation by uranium(III) complexes is now relatively well understood, with oxo/carbonate formation predominating as CO{sub 2} is readily reduced to CO, but isolated thorium(III) CO{sub 2} activation is unprecedented. We show that the thorium(III) complex, [Th(Cp''){sub 3}] (1, Cp''={C_5H_3(SiMe_3)_2-1,3}), reacts with CO{sub 2} to give the mixed oxalate-carboxylate thorium(IV) complex [{Th(Cp'')_2[κ"2-O_2C{C_5H_3-3,3'-(SiMe_3)_2}]}{sub 2}(μ-κ{sup 2}:κ{sup 2}-C{sub 2}O{sub 4})] (3). The concomitant formation of oxalate and carboxylate is unique for CO{sub 2} activation, as in previous examples either reduction or insertion is favored to yield a single product. Therefore, thorium(III) CO{sub 2} activation can differ from better understood uranium(III) chemistry. (copyright 2016 The Authors. Published by Wiley-VCH Verlag GmbH and Co. KGaA.)

  20. Systematic theoretical investigation of the zero-field splitting in Gd(III) complexes: Wave function and density functional approaches

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Shehryar, E-mail: sherkhan@fysik.su.se; Odelius, Michael, E-mail: odelius@fysik.su.se [Department of Physics, Stockholm University, AlbaNova University Center, S-106 91 Stockholm (Sweden); Kubica-Misztal, Aleksandra [Institute of Physics, Jagiellonian University, ul. Reymonta 4, PL-30-059 Krakow (Poland); Kruk, Danuta [Faculty of Mathematics and Computer Science, University of Warmia and Mazury in Olsztyn, Sloneczna 54, Olsztyn PL-10710 (Poland); Kowalewski, Jozef [Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm (Sweden)

    2015-01-21

    The zero-field splitting (ZFS) of the electronic ground state in paramagnetic ions is a sensitive probe of the variations in the electronic and molecular structure with an impact on fields ranging from fundamental physical chemistry to medical applications. A detailed analysis of the ZFS in a series of symmetric Gd(III) complexes is presented in order to establish the applicability and accuracy of computational methods using multiconfigurational complete-active-space self-consistent field wave functions and of density functional theory calculations. The various computational schemes are then applied to larger complexes Gd(III)DOTA(H{sub 2}O){sup −}, Gd(III)DTPA(H{sub 2}O){sup 2−}, and Gd(III)(H{sub 2}O){sub 8}{sup 3+} in order to analyze how the theoretical results compare to experimentally derived parameters. In contrast to approximations based on density functional theory, the multiconfigurational methods produce results for the ZFS of Gd(III) complexes on the correct order of magnitude.