Synthesis and characterization of bright green terbium coordination complex derived from 1,4-bis(carbonylmethyl)terephthalate: Structure and luminescence properties

Science.gov (United States)

Ma, Mengjiao; Li, Congcong; Shu, Dengkun; Wang, Chaohua; Xi, Peng

2018-02-01

A photoluminescent terbium (Tb) complex involving a novel benzoic-acid compound with a unique coordinated structure, namely 1,4-bis(carbonylmethyl)terephthalate (BCMT), has been designed and synthesized. The new coordinate structure and energy-transfer mechanism between the ligand and Tb(III) ions were investigated in detail. The results demonstrated that the BCMT-Tb(III) complex shows strong fluorescence intensity (4 × 106 a.u.) and long fluorescence lifetime (1.302 ms), owing to the favorable degree of energy matching between the triplet excited level of the ligand and the resonant level of Tb(III) ions. Based on the analysis of three-dimensional luminescence spectra, the as-prepared Tb(III) complex can be effectively excited in the range of 250-310 nm, and it shows high color purity, with a bright green appearance.

Fine structure studies of terbium atoms

International Nuclear Information System (INIS)

Abhay Kumar; Bandyopadhyay, Krishnanath; Niraj Kumar

2012-01-01

Terbium (Z = 65) is a typical rare-earth element. Fine structure of spectural lines of terbium (Tb) are presented using the laser optogalvanic spectroscopic technique. Altogether eighty transitions in the 5686-6367 A range have been observed in the fine structure spectrum of 159 Tb. Wavelengths of all the observed transitions have been determined. Out of 80 transitions of Tb, a total of 59 transitions are being reported for the first time. Classifications of 39 new transitions have been provided using the known energy levels, Doppler-limited optogalvanic spectroscopic technique is employed to study the fine structure (fs) 159 Tb. (author)

Raman spectroscopy study of the doping effect of the encapsulated terbium halogenides on single-walled carbon nanotubes

Energy Technology Data Exchange (ETDEWEB)

Kharlamova, M.V.; Kramberger, C.; Mittelberger, A. [University of Vienna, Faculty of Physics, Vienna (Austria)

2017-04-15

In the present work, the doping effect of terbium chloride, terbium bromide, and terbium iodide on single-walled carbon nanotubes (SWCNTs) was compared by Raman spectroscopy. A precise investigation of the doping-induced alterations of the Raman modes of the filled SWCNTs was conducted. The shifts of the components of the Raman modes and modification of their profiles allowed concluding that the inserted terbium halogenides have acceptor doping effect on the SWCNTs, and the doping efficiency increases in the line with terbium iodide, terbium bromide, and terbium chloride. (orig.)

Optical properties of phosphorescent nano-silicon electrochemically doped with terbium

Energy Technology Data Exchange (ETDEWEB)

Gelloz, Bernard [Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan); Mentek, Romain; Koshida, Nobuyoshi [Tokyo University A and T, 2-24-16 Nakacho, Koganei, Tokyo 184-8588 (Japan)

2012-12-15

Hybrid thin films consisting of oxidized nano-silicon doped with terbium have been fabricated. Nano-silicon was formed by electrochemical etching of silicon wafers. Terbium was incorporated into nano-silicon pores by electrochemical deposition. Different oxidizing thermal treatments were applied to the films. The samples treated by high-pressure water vapor annealing (HWA) exhibited strong blue emission with a phosphorescent component, as previously reported by our group. The low temperature (260 C) HWA also led to strong emission from Tb{sup 3+} ions, whereas typical high temperature (900 C) treatment generally used to activate Tb{sup 3+} ions in silicon-based materials led to less luminescent samples. Spectroscopic and dynamic analyses suggest that terbium was incorporated as a separate oxide phase in the pores of the porous nano-silicon. The PL of the terbium phase and nano-silicon phase exhibit different temperature and excitation power dependences suggesting little optical or electronic interaction between the two phases. The luminescence of terbium is better activated at low temperature (260 C) than at high temperature (900 C). The hybrid material may find some applications in photonics, for instance as a display material. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Improved terbium-doped, lithium-loaded glass scintillator fibers

International Nuclear Information System (INIS)

Spector, G.B.; McCollum, T.; Spowart, A.R.

1993-01-01

An improved terbium-doped, 6 Li-loaded glass scintillator has been drawn into fibers. Tests indicate that the neutron detection response of the fibers is superior to the response with fibers drawn from the original terbium-doped glass. The new fibers offer less attenuation (1/e length of ∝40 cm) and improved gamma ray/neutron discrimination. The improved fibers will be incorporated in a scintillator fiber optic long counter for neutron detection. (orig.)

Determination of fluoxetine in pharmaceutical and biological samples based on the silver nanoparticle enhanced fluorescence of fluoxetine-terbium complex.

Science.gov (United States)

Lotfi, Ali; Manzoori, Jamshid L

2016-11-01

In this study, a simple and sensitive spectrofluorimetric method is presented for the determination of fluoxetine based on the enhancing effect of silver nanoparticles (AgNPs) on the terbium-fluoxetine fluorescence emission. The AgNPs were prepared by a simple reduction method and characterized by UV-Vis spectroscopy and transmission electron microscopy. It was indicated that these AgNPs have a remarkable amplifying effect on the terbium-sensitized fluorescence of fluoxetine. The effects of various parameters such as AgNP and Tb 3+ concentration and the pH of the media were investigated. Under obtained optimal conditions, the fluorescence intensity of the terbium-fluoxetine-AgNP system was enhanced linearly by increasing the concentration of fluoxetine in the range of 0.008 to 19 mg/L. The limit of detection (b + 3s) was 8.3 × 10 -4 mg/L. The interference effects of common species found in real samples were also studied. The method had good linearity, recovery, reproducibility and sensitivity, and was satisfactorily applied for the determination of fluoxetine in tablet formulations, human urine and plasma samples. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Determination of fluoroquinolone antibiotics by microchip capillary electrophoresis along with time-resolved sensitized luminescence of their terbium(III) complexes

International Nuclear Information System (INIS)

Sierra-Rodero, Marina; Fernández -Romero, Juan Manuel; Gómez -Hens, Agustina

2014-01-01

We report on the time-resolved detection of the three fluoroquinolone (FQs) antibiotics ciprofloxacin (CIP), enrofloxacin (ENR) and flumequine (FLU). On addition of terbium(III) ions, the terbium(III)-FQs chelates are formed in-situ in an on-capillary derivatization reaction of a microfluidic system. The laser-induced terbium(III)-sensitized luminescence of the chelates is measured at excitation/emission wavelengths of 337/545 nm. The analytes can be separated and quantified within less than 4 min. A solid phase extraction step for analyte preconcentration can be included prior to chelation and microchip capillary electrophoresis. The analytical ranges of the calibration graphs for CIP, ENR and FLU are from 10.6 to 60.0, 10.3 to 51.0, and 11.5 to 58.8 ng mL −1 , respectively, and the detection limits are 3.2, 3.1 and 3.6 ng mL −1 , respectively. The precision was established at two concentration levels of each analyte and revealed relative standard deviations in the range from 3.0 to 10.2 %. The method was applied to the analysis of FQ-spiked water samples. (author)

Lattice dynamics of terbium

DEFF Research Database (Denmark)

Houmann, Jens Christian Gylden; Nicklow, R.M.

1970-01-01

The frequency-wave-vector dispersion relation for the normal modes of vibration of terbium at room temperature has been measured by means of slow-neutron inelastic scattering techniques. The triple-axis spectrometer at the Oak Ridge high flux isotope reactor was used, mostly in the constant-Q mode...

Study of the nucleotide binding site of the yeast Schizosaccharomyces pombe plasma membrane H+-ATPase using formycin triphosphate-terbium complex

International Nuclear Information System (INIS)

Ronjat, M.; Lacapere, J.J.; Dufour, J.P.; Dupont, Y.

1987-01-01

The plasma membrane of yeasts contains an H+-ATPase similar to the other cation transport ATPases of eukaryotic organisms. This enzyme has been purified and shows H+ transport in reconstituted vesicles. In the presence of Mg2+, formycin triphosphate (FTP) is hydrolyzed by the H+-ATPase and supports H+ transport. When combined with terbium ion, FTP (Tb-FTP) and ATP (Tb-ATP) are no longer hydrolyzed. Competition between Mg-ATP and Tb-FTP for ATP hydrolysis indicates that terbium-associated nucleotides bind to the catalytic site of the H+-ATPase. The fluorescent properties of the Tb-FTP complex were used to study the active site of the H+-ATPase. Fluorescence of Tb-FTP is greatly enhanced upon binding into the nucleotide site of H+-ATPase with a dissociation constant of 1 microM. Tb-ATP, Tb-ADP, and Tb-ITP are competitive inhibitors of Tb-FTP binding with Ki = 4.5, 5.0, and 6.0 microM, respectively. Binding of Tb-FTP is observed only in the presence of an excess of Tb3+ with an activation constant Ka = 25 microM for Tb3+. Analysis of the data reveals that the sites for Tb-FTP and Tb3+ binding are independent entities. In standard conditions these sites would be occupied by Mg-ATP and Mg2+, respectively. These findings suggest an important regulatory role of divalent cations on the activity of H+-ATPase. Replacement of H 2 O by D 2 O in the medium suggests the existence of two types of nucleotide binding sites differing by the hydration state of the Tb3+ ion in the bound Tb-FTP complex

Sensitization effects of supramolecular assemblies on the luminescence of terbium-ion prulifloxacin complexes

Energy Technology Data Exchange (ETDEWEB)

Wang Hong; Yi Chongyue; Li Xue; Fang Fang [School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Yang Yajiang, E-mail: yjyang@mail.hust.edu.c [School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

2011-04-15

Luminescence enhancement of terbium-ion prulifloxacin complexes (Tb(III)-PUFX) in supramolecular hydrogels formed by assembly of 1,3:2,4-di-O-benzylidene-D-sorbitol (DBS) was investigated by steady-state fluorescence, varying temperature fluorescence and time-resolved fluorescence. The luminescence images show that Tb(III)-PUFX were dispersed in the DBS gels. The luminescence intensity of Tb(III)-PUFX in the DBS gels was significantly increased in comparison with that in corresponding aqueous solutions. The varying temperature fluorescent spectra show that the luminescence intensity of Tb(III)-PUFX decreased with an increase in the temperature. This implies that the luminescence enhancement of Tb(III)-PUFX is related to the dissociation and the formation of the DBS assemblies. Time-resolved fluorescence measurements show slower rotational motion in DBS gels in comparison with that in the corresponding aqueous solutions. This may be ascribed to a unique microstructure of three-dimensional network formed by DBC aggregates, resulting in deactivation of the nonradiative relaxation. The images of field emission scanning electron microscopy and polarized optical microscopy indicate that the morphology of the DBS assemblies was not influenced upon addition of Tb(III)-PUFX to the DBS gels.

Effect of solvents on relation of intensities of bands of luminescence spectra of terbium and dysprosium ions in solutions of their complexes with acetoacetic ester

International Nuclear Information System (INIS)

Kononenko, L.I.; Bel'tyukova, S.V.; Meshkova, S.B.; Kravchenko, T.B.; Poluehktov, N.S.

1978-01-01

An investigation is made of the effect of different solvents on the ratio of the intensity of luminescence spectrum bands of terbium and dysprosium ions, corresponding and not corresponding to ''supersensitive'' transitions in complex compounds with acetoacetic ether. A dependence is established between these values and the dielectric constant of the solvent, and also parallels in their changes, which indicate the similar manifestation of the effect of solvents in both elements. A correlation is observed between ratios of the intensity of luminescence spectrum bands and values of forces of neodymium complex absorption band oscillators in different solvents

Magneto-elastic interactions in terbium

DEFF Research Database (Denmark)

Jensen, J.

1971-01-01

. These calculations agree semi-quantitatively with the results of experimental measurements. The author has examined the extent to which this simple picture is applicable to explain the magnon-phonon interactions in terbium, which have been observed at finite wave vectors by inelastic neutron scattering...

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

A new luminescent terbium 4-methylsalicylate complex as a novel sensor for detecting the purity of methanol.

Science.gov (United States)

Zeng, Cheng-Hui; Yang, Yang-Yi; Zhu, Yi-Min; Wang, Hong-Ming; Chu, Tian-Shu; Ng, Seik Weng

2012-01-01

A new dinuclear terbium complex [Tb(2)(4-msal)(6)(H(2)O)(4)]·6H(2)O (1) (4-msal = 4-methylsalcylate) was synthesized. Its structure was determined by single crystal X-ray diffraction, and the complex was characterized by PXRD, FT-IR, fluorescence, TGA and DTA. Complex 1 exists as discrete molecules that are linked by extensive O-H … O hydrogen bonds into a 3D network. The luminescence lifetimes of 3 μM methanol solution and solid sample of 1 are 1.321 and 1.009 ms, respectively. The quantum yield of solid sample is 6.0%. The luminescence quenched more than 50% when 3% (vol/vol) different impurities (acetone, acetonitrile, chloroform, dichloromethane, dioxane, DMF, DMSO, ethanol, ether, ethyl acetate, glycol, H(2)O, hexane, TEA, THF and toluene or their mixture) were added. The inverse linear relationship between the Lg value of fluorescence intensity and the volume ratio of the minor component (to a maximum of 20%) is interpreted in terms of LgI = a-bX (I: luminescence intensity; X: volume ratio of impurities in methanol; a, b are constants). So 1 is a potential luminescent sensor for analyzing the purity of methanol. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

Highly n -doped graphene generated through intercalated terbium atoms

Science.gov (United States)

Daukiya, L.; Nair, M. N.; Hajjar-Garreau, S.; Vonau, F.; Aubel, D.; Bubendorff, J. L.; Cranney, M.; Denys, E.; Florentin, A.; Reiter, G.; Simon, L.

2018-01-01

We obtained highly n -type doped graphene by intercalating terbium atoms between graphene and SiC(0001) through appropriate annealing in ultrahigh vacuum. After terbium intercalation angle-resolved-photoelectron spectroscopy (ARPES) showed a drastic change in the band structure around the K points of the Brillouin zone: the well-known conical dispersion band of a graphene monolayer was superposed by a second conical dispersion band of a graphene monolayer with an electron density reaching 1015cm-2 . In addition, we demonstrate that atom intercalation proceeds either below the buffer layer or between the buffer layer and the monolayer graphene. The intercalation of terbium below a pure buffer layer led to the formation of a highly n -doped graphene monolayer decoupled from the SiC substrate, as evidenced by ARPES and x-ray photoelectron spectroscopy measurements. The band structure of this highly n -doped monolayer graphene showed a kink (a deviation from the linear dispersion of the Dirac cone), which has been associated with an electron-phonon coupling constant one order of magnitude larger than those usually obtained for graphene with intercalated alkali metals.

Cerium(terbium, erbium)chloride-choline chloride aqueous systems

International Nuclear Information System (INIS)

Gajfutdinova, R.K.; Zhuravlev, E.F.; Bikbaeva, G.G.; Domrachev, V.N.; Vanskova, G.I.

1985-01-01

To clarify the effect of rare earth nature on mutual solubility of rare earth salts and amines the solubility of solid phases in the systems, consisting of choline chloride, water and cerium, terbium, erbium chlorides, has been studied. It is established, that solubility isotherms of all the systems, testify to the formation of new solid phases of the composition: Ce(Tb, Er)xCl 3 x2C 5 H 14 ONClx3H 2 O. Individuality of new solid phases is proved by DTA method, the composition is confirmed by chemical analysis and data of PMR spectra, for choline chloride and its complexes with rare earth chlorides of the given composition PMR and IR spectra are studied

Critical scattering of neutrons from terbium

DEFF Research Database (Denmark)

Als-Nielsen, Jens Aage; Dietrich, O.W.; Marshall, W.

1968-01-01

The inelasticity of the critical scattering of neutrons in terbium has been measured above the Neél temperature at the (0, 0, 2−Q) satellite position. The results show that dynamic slowing down of the fluctuations does occur in a second‐order phase transition in agreement with the general theory...

Elastic properties of terbium

DEFF Research Database (Denmark)

Spichkin, Y.I.; Bohr, Jakob; Tishin, A.M.

1996-01-01

The temperature dependence of the Young modulus along the crystallographic axes b and c (E(b) and E(c)), and the internal friction of a terbium single crystal have been measured. At 4.2 K, E(b) and E(c) are equal to 38 and 84.5 GPa, respectively. The lattice part of the Young modulus and the Debye...... temperature has been calculated. The origin of the Young modulus anomalies arising at the transition to the magnetically ordered state is discussed....

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)

Systems of pyridine, piperidine, piperazine, morpholine hydrochlorides-terbium (dysprosium) chloride-water

International Nuclear Information System (INIS)

Gajfutdinova, R.K.; Sharafutdinova, A.A.; Murinov, Yu.I.

1988-01-01

The isothermal cross section method at 25 and 50 deg C is applied to study pyridine hydrochloride-terbium chloride-water (1) piperidine hydrochloride-dysprosium chloride-water (2), piperazine dihydrochloride-dysprosium chloride-water (3) and morpholine hydrochloride-terbium chloride (4) systems. Solubility isotherma prove the formation of incongruently soluble compound of the TbCl 3 x6C 5 H 5 NxHCl composition systems (1). The individuality of the new solid phase is proved by the chemical and DTA methods. Systems (2-4) are of a simple eutonic type

Molecular Orientation of a Terbium(III)-Phthalocyaninato Double-Decker Complex for Effective Suppression of Quantum Tunneling of the Magnetization.

Science.gov (United States)

Yamabayashi, Tsutomu; Katoh, Keiichi; Breedlove, Brian K; Yamashita, Masahiro

2017-06-15

Single-molecule magnet (SMM) properties of crystals of a terbium(III)-phthalocyaninato double-decker complex with different molecular packings ( 1 : TbPc₂, 2 : TbPc₂·CH₂Cl₂) were studied to elucidate the relationship between the molecular packing and SMM properties. From single crystal X-ray analyses, the high symmetry of the coordination environment of 2 suggested that the SMM properties were improved. Furthermore, the shorter intermolecular Tb-Tb distance and relative collinear alignment of the magnetic dipole in 2 indicated that the magnetic dipole-dipole interactions were stronger than those in 1 . This was confirmed by using direct current magnetic measurements. From alternating current magnetic measurements, the activation energy for spin reversal for 1 and 2 were similar. However, the relaxation time for 2 is three orders of magnitude slower than that for 1 in the low- T region due to effective suppression of the quantum tunneling of the magnetization. These results suggest that the SMM properties of TbPc₂ highly depend on the molecular packing.

Investigation of terbium scandate as an alternative gate dielectric in fully depleted transistors

OpenAIRE

Roeckerath, M.; Lopes, J. M. J.; Durgun Özben, E.; Urban, C.; Schubert, J.; Mantl, S.; Jia, Y.; Schlom, D.G.

2010-01-01

Terbium scandate thin films were deposited by e-gun evaporation on (100) silicon substrates. Rutherford backscattering spectrometry and x-ray diffraction studies revealed homogeneous chemical compositions of the films. A dielectric constant of 26 and CV-curves with small hystereses were measured as well as low leakage current densities of < 1 nA/cm(2). Fully depleted n-type field-effect transistors on thin silicon-on-insulator substrates with terbium scandate gate dielectrics were fabricated ...

Infrared X-ray and thermal analysis of terbium soaps

International Nuclear Information System (INIS)

Mehrotra, K.N.; Sharma, N.

1996-01-01

Terbium sops (laureate, myristate and palmitate) were synthesized by direct metathesis of corresponding potassium soap with an aqueous solution of terbium nitrate. The physico-chemical characteristics of soaps in solid state were investigated by IR spectra, X-ray diffraction patterns and TGA measurements. The IR results revealed that the fatty acids exist in dimeric state through hydrogen bonding while the soaps possess partial ionic character. The X-ray analysis showed that the soaps have double layer structure with molecular axes slightly inclined to the basal plane. The thermal analysis suggested that the decomposition of soaps occur in two steps. The energy of activation, order of reaction and various kinetic parameters (i.e. frequency factor, entropy of activation and free energy) for the thermal decomposition of soaps were evaluated. (author). 26 refs, 4 figs, 4 tabs

Nuclear magnetic resonance in ferromagnetic terbium metal

International Nuclear Information System (INIS)

Cha, C.L.T.

1974-01-01

The magnetic properties of terbium were studied by the method of zero field nuclear magnetic resonance at 1.5 to 4 and 85 to 160 0 K. Two unconventional experimental techniques have been employed: the swept frequency and the swept temperature technique. Near 4 0 K, triplet resonance line structures were found and interpreted in terms of the magnetic domain and wall structures of ferromagnetic terbium. In the higher temperature range, temperature dependence of the resonance frequency and the quadrupole splitting were measured. The former provides a measurement of the temperature dependence of the magnetization M, and it agrees with bulk M measurements as well as the latest spin wave theory of M(T) (Brooks 1968). The latter agrees well with a calculation using a very general single ion density matrix for collective excitations (Callen and Shtrikman 1965). In addition, the small temperature-independent contribution to the electric field gradient at the nucleus due to the lattice and conduction electrons was untangled from the P(T) data. Also an anomalous and unexplained relaxation phenomenon was also observed

Terbium nitrate luminescence quenching by eosin in he presence of lithium perchlorate in sulfolane solutions

International Nuclear Information System (INIS)

Ostakhov, S.S.; Kolosnitsyn, V.S.; Krasnogorskaya, N.N.; Kazakov, V.P.

2000-01-01

Quenching of terbium nitrate luminescence by anionic dye, eosin, in the presence of lithium perchlorate in sulfolane solutions was studied. Temperature dependence of terbium nitrate luminescence in sulfolane solutions in the presence of perchlorate anions were considered. The values of energy required for water molecular substitution in Tb 3+ ion coordination sphere for solvent molecule in electrolyte solution were ascertained [ru

Determination of trace amounts of rare earth elements in samarium, terbium and disprosium oxides by graphite furnace atomic-absorption spectrometry

International Nuclear Information System (INIS)

Dantas, E.S.K.

1990-01-01

A graphite furnace atomic-absorption spectrometry method for the determination of neodymium, europium, terbium, dysprosium and yttrium at trace level in samarium oxide; of samarium, europium, dysprosium, holmium, erbium and yttrium in terbium oxide and of europium, terbium, holmium, erbium and yttrium in dysprosium oxide was established. The best pyrolysis and atomization temperatures were determined for each lanthanide considered. Calibration curves were obtained for the pure elements, for binary mixtures formed by the matrix and each of the lanthanides studied and, finally, for the complex mixtures constituted by the matrix and all the other lanthanide of the group under scrutiny. This study has been carried out to examine the interference of the presence of one lanthanide on the behaviour of the other, since a lack of linearity on the calibration curves has been observed in some cases. Detection and determination limits have been determined as well. The detection limits encountered were within the range 0.002 to 0.3% for different elements. The precision of the method expressed as the relative standard deviation was calculated for each element present in each of the matrices studied. The conclusion arrived at is that the method can be applied for determining the above mentioned lanthanides present in the matrices studied with purity up to 99.50%. (author)

Construction of the energy matrix for complex atoms. Part VIII: Hyperfine structure HPC calculations for terbium atom

Science.gov (United States)

Elantkowska, Magdalena; Ruczkowski, Jarosław; Sikorski, Andrzej; Dembczyński, Jerzy

2017-11-01

A parametric analysis of the hyperfine structure (hfs) for the even parity configurations of atomic terbium (Tb I) is presented in this work. We introduce the complete set of 4fN-core states in our high-performance computing (HPC) calculations. For calculations of the huge hyperfine structure matrix, requiring approximately 5000 hours when run on a single CPU, we propose the methods utilizing a personal computer cluster or, alternatively a cluster of Microsoft Azure virtual machines (VM). These methods give a factor 12 performance boost, enabling the calculations to complete in an acceptable time.

Semiconductor composition containing iron, dysprosium, and terbium

Science.gov (United States)

Pooser, Raphael C.; Lawrie, Benjamin J.; Baddorf, Arthur P.; Malasi, Abhinav; Taz, Humaira; Farah, Annettee E.; Kalyanaraman, Ramakrishnan; Duscher, Gerd Josef Mansfred; Patel, Maulik K.

2017-09-26

An amorphous semiconductor composition includes 1 to 70 atomic percent iron, 15 to 65 atomic percent dysprosium, 15 to 35 atomic percent terbium, balance X, wherein X is at least one of an oxidizing element and a reducing element. The composition has an essentially amorphous microstructure, an optical transmittance of at least 50% in at least the visible spectrum and semiconductor electrical properties.

Low-temperature thermal conductivity of terbium-gallium garnet

International Nuclear Information System (INIS)

Inyushkin, A. V.; Taldenkov, A. N.

2010-01-01

Thermal conductivity of paramagnetic Tb 3 Ga 5 O 12 (TbGG) terbium-gallium garnet single crystals is investigated at temperatures from 0.4 to 300 K in magnetic fields up to 3.25 T. A minimum is observed in the temperature dependence κ(T) of thermal conductivity at T min = 0.52 K. This and other singularities on the κ(T) dependence are associated with scattering of phonons from terbium ions. The thermal conductivity at T = 5.1 K strongly depends on the magnetic field direction relative to the crystallographic axes of the crystal. Experimental data are considered using the Debye theory of thermal conductivity taking into account resonance scattering of phonons from Tb 3+ ions. Analysis of the temperature and field dependences of the thermal conductivity indicates the existence of a strong spin-phonon interaction in TbGG. The low-temperature behavior of the thermal conductivity (field and angular dependences) is mainly determined by resonance scattering of phonons at the first quasi-doublet of the electron spectrum of Tb 3+ ion.

Characterization of antibody-chelator conjugates: Determination of chelator content by terbium fluorescence titration

Energy Technology Data Exchange (ETDEWEB)

Brandt, K.D.; Schnobrich, K.E.; Johnson, D.K. (Abbott Laboratories, Department 90M, Abbott Park, IL (United States))

1991-01-01

Fluorescence titrations were performed by adding varying mole ratios of terbium(III) to antibody conjugates formed by benzyl isothiocyanate derivatives of three different polyaminopolycarboxylate chelators (NTA, EDTA, and DTPA) and the results compared to values for average chelator content obtained by cobalt-57 binding assays. For two different murine monoclonal antibodies, the average chelator content obtained by terbium fluorescence titration correlated closely with that measured by the cobalt-57 binding assay. It is concluded that lanthanide fluorescence titrations provide a useful alternative to radiometal binding assays for the determination of chelator content in protein-chelator conjugates.

Characterization of antibody-chelator conjugates: Determination of chelator content by terbium fluorescence titration

International Nuclear Information System (INIS)

Brandt, K.D.; Schnobrich, K.E.; Johnson, D.K.

1991-01-01

Fluorescence titrations were performed by adding varying mole ratios of terbium(III) to antibody conjugates formed by benzyl isothiocyanate derivatives of three different polyaminopolycarboxylate chelators (NTA, EDTA, and DTPA) and the results compared to values for average chelator content obtained by cobalt-57 binding assays. For two different murine monoclonal antibodies, the average chelator content obtained by terbium fluorescence titration correlated closely with that measured by the cobalt-57 binding assay. It is concluded that lanthanide fluorescence titrations provide a useful alternative to radiometal binding assays for the determination of chelator content in protein-chelator conjugates

Detection of Bacterial Endospores in Soil by Terbium Fluorescence

Directory of Open Access Journals (Sweden)

Andrea Brandes Ammann

2011-01-01

Full Text Available Spore formation is a survival mechanism of microorganisms when facing unfavorable environmental conditions resulting in “dormant” states. We investigated the occurrence of bacterial endospores in soils from various locations including grasslands (pasture, meadow, allotment gardens, and forests, as well as fluvial sediments. Bacterial spores are characterized by their high content of dipicolinic acid (DPA. In the presence of terbium, DPA forms a complex showing a distinctive photoluminescence spectrum. DPA was released from soil by microwaving or autoclaving. The addition of aluminium chloride reduced signal quenching by interfering compounds such as phosphate. The highest spore content (up to 109 spores per gram of dry soil was found in grassland soils. Spore content is related to soil type, to soil depth, and to soil carbon-to-nitrogen ratio. Our study might provide a basis for the detection of “hot spots” of bacterial spores in soil.

X-ray fluorescence analysis of terbium oxide for rare earth impurities

International Nuclear Information System (INIS)

Chandola, L.C.; Machado, I.J.; Mohile, A.N.

1975-01-01

A method for the determination of Sm 2 O 3 , Eu 2 O 3 , Gd 2 O 3 , Dy 2 O 3 , Ho 2 O 3 and Y 2 O 3 in terbium oxide is described. The sample is converted to terbium oxalate, mixed with boric acid binder in the ratio 2:1, pelleted at a pressure of 20 tons over a boric acid backing pellet and irradiated with x-rays from a tungsten tube operated by Philips PW 1140 generator. The secondary x-rays thus generated are analysed by a LiF (200) crystal in Philips PW 1220 x-ray fluorescence spectrometer using suitable detectors. The minimum determination limit (MDL) is 0.01% for all rare earth oxides determined except for Y 2 O 3 for which it is 0.005%. (author)

Investigation of terbium scandate as an alternative gate dielectric in fully depleted transistors

Science.gov (United States)

Roeckerath, M.; Lopes, J. M. J.; Özben, E. Durǧun; Urban, C.; Schubert, J.; Mantl, S.; Jia, Y.; Schlom, D. G.

2010-01-01

Terbium scandate thin films were deposited by e-gun evaporation on (100) silicon substrates. Rutherford backscattering spectrometry and x-ray diffraction studies revealed homogeneous chemical compositions of the films. A dielectric constant of 26 and CV-curves with small hystereses were measured as well as low leakage current densities of <1 nA/cm2. Fully depleted n-type field-effect transistors on thin silicon-on-insulator substrates with terbium scandate gate dielectrics were fabricated with a gate-last process. The devices show inverse subthreshold slopes of 80 mV/dec and a carrier mobility for electrons of 225 cm2/V•s was extracted.

Magneto-optical studies of valence instability in europium and terbium phosphors

Czech Academy of Sciences Publication Activity Database

Rodrigues, L.C.v.; Hölsä, J.; Brito, H.F.; Maryško, Miroslav; Matos, J.R.; Paturi, P.; Rodrigues, R.V.; Lastusaari, M.

2016-01-01

Roč. 170, Feb (2016), 701-706 ISSN 0022-2313 Institutional support: RVO:68378271 Keywords : valence * europium * terbium * oxysulfide and -sulfate * phosphors * paramagnetic susceptibility Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.686, year: 2016

Cross sections from 800 MeV proton irradiation of terbium

Energy Technology Data Exchange (ETDEWEB)

Engle, J.W., E-mail: jwengle@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Mashnik, S.G.; Bach, H.; Couture, A.; Jackman, K.; Gritzo, R.; Ballard, B.D.; Fassbender, M.; Smith, D.M.; Bitteker, L.J.; Ullmann, J.L.; Gulley, M.S.; Pillai, C.; John, K.D.; Birnbaum, E.R. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Nortier, F.M., E-mail: meiring@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2012-11-02

Terbium foils were irradiated with 800 MeV protons to ascertain the potential for production of lanthanide isotopes of interest in medical, astrophysical, and basic science research and to contribute to nuclear data repositories. Isotopes produced in the foil were quantified by gamma spectroscopy. Cross sections for 35 isotopes produced in the irradiation are reported and compared with predictions by the MCNP6 transport code using the CEM03.03, Bertini and INCL + ABLA event generators. Our results indicate the need to accurately consider fission and fragmentation of relatively light target nuclei like terbium in the modeling of nuclear reactions at 800 MeV. The predictive power of the code was found to be different for each event generator tested but was satisfactory for most of the product yields in the mass region where spallation reactions dominate. However, none of the event generators' results are in complete agreement with measured data.

Interaction of terbium group metal oxides with carbon

International Nuclear Information System (INIS)

Vodop'yanov, A.G.; Baranov, S.V.; Kozhevnikov, G.N.

1990-01-01

Mechanism of carbothermal reduction of terbium group metals from oxides is investigated using thermodynamic and kinetic analyses. Interaction of metal oxides with carbon covers dissociation of metal oxides and reduction by carbon monoxide, which contribution into general reduction depends on CO pressure. Temperatures of reaction beginning for batch initial components at P=1.3x10 -4 and P CO =0.1 MPa and of formation of oxycarbide melts are determined

Terbium oxide at high pressures

International Nuclear Information System (INIS)

Dogra, Sugandha; Sharma, Nita Dilawar; Singh, Jasveer; Bandhyopadhyay, A.K.

2011-01-01

In this work we report the behaviour of terbium oxide at high pressures. The as received sample was characterized at ambient by X-ray diffraction and Raman spectroscopy. The X-ray diffraction showed the sample to be predominantly cubic Tb 4 O 7 , although a few peaks also match closely with Tb 2 O 3 . In fact in a recent study done on the same sample, the sample has been shown to be a mixture of Tb 4 O 7 and Tb 2 O 3 . The sample was subjected to high pressures using a Mao-Bell type diamond anvil cell upto a pressure of about 42 GPa with ruby as pressure monitor

Terbium(III) ions as sensitizers of oxidation of indole and its derivatives in Fenton system

Energy Technology Data Exchange (ETDEWEB)

Kaczmarek, Małgorzata, E-mail: mkaczmar@amu.edu.pl; Staninski, Krzysztof

2017-03-15

Oxidation of indole and its derivatives in the Fenton system as a source of oxidising agents, in the presence of terbium(III) ions was studied by chemiluminescence methods to get the kinetic curves of emission decay and spectral distributions of chemiluminescence. Terbium(III) ions acted as a sensitizer of the mixtures Tb(III)-Fe(II)/Fe(III)-H{sub 2}O{sub 2}-indole or its derivative (tryptophan, tryptamine, indole-3-acetic acid and indole-3-acetyl aspartic acid). For the above indolic compounds, linear dependencies of integrated intensity of chemiluminescence on concentration of indolic compound in water and in water-acetonitrile solution were obtained. The limits of detection (LOD) and quantification (LOQ) of the indolic compounds studied were found to be by one or two orders of magnitude lower in the system with terbium(III) ions than without them. - Highlights: • Chemiluminescence emitted on oxidation of indolic compounds in Fenton system. • Tb (III) ions as sensitizers of indolic compounds oxidation in solutions. • Linear relations between CL intensity and indolic compound concentration.

Green light emission in aluminum oxide powders doped with different terbium concentrations

Energy Technology Data Exchange (ETDEWEB)

Mariscal B, L; Falcony, C. [IPN, Centro de Investigacion y de Estudios Avanzados, 07360 Ciudad de Mexico (Mexico); Carmona T, S.; Murrieta, H.; Sanchez A, M. A. [UNAM, Instituto de Fisica, 04510 Ciudad de Mexico (Mexico); Vazquez A, R. [IPN, Escuela Superior de Computo, 07738 Ciudad de Mexico (Mexico); Garcia R, C. M., E-mail: mariscal2005@gmail.com [UNAM, Facultad de Ciencias, 04510 Ciudad de Mexico (Mexico)

2016-11-01

Different emission intensities presented in aluminum oxide phosphors corresponding to different concentrations of doping performed with terbium are analyzed. The phosphors were synthesized by the evaporation technique and were characterized by photo and cathodoluminescence, X-ray diffraction and EDS techniques for different incorporation percentages of terbium as dopant; they show characteristic transitions in 494, 543, 587 and 622 nm, corresponding to {sup 5}D{sub 4} → {sup 7}F{sub 6}, {sup 5}D{sub 4} → {sup 7}F{sub 5}, {sup 5}D{sub 4} → {sup 7}F{sub 4} and {sup 5}D{sub 4} → {sup 7}F{sub 3}, respectively when they are excited with λ{sub exc} = 380 nm wavelength at room temperature. The results of X-ray diffraction show the presence of α-Al{sub 2}O{sub 3} phases with peaks located at 2θ = 25.78, 35.34, 37.96, 43.56, 45.8, 52.74, 57.7, 61.5, 66.74, 68.44, 77.12 and 80.94, and the δ-Al{sub 2}O-3 phase 2θ = 32.82, 45.8, 61.36 and 66.74. These compounds were heat treated for two hours at 1100 degrees Celsius. EDS analyzes indicate that these compounds have close to 60% oxygen around of 40% aluminum in the presence of terbium as dopant which indicates a stoichiometry close to the expected one for alumina. (Author)

Electroanalytical performance of a terbium(III)-selective sensor based on a neutral ionophore in environmental and medicinal samples

Energy Technology Data Exchange (ETDEWEB)

Gupta, V.K.; Singh, A.K.; Gupta, Barkha [Indian Institute of Technology-Roorkee, Department of Chemistry, Roorkee (India)

2008-04-15

A new highly selective terbium(III) electrode was prepared with a polymeric film doped using S-2-benzothiazolyl-2-amino-{alpha}-(methoxyimino)-4-thiazolethiol acetate as an electroactive material, benzyl acetate (BA) as a plasticizer, and potassium tetrakis(4-chlorophenyl) borate (KTpClPB) as an anionic site in the percentage ratio 3.17:1.58:63.4:31.7 (ionophore-KTpClPB-BA-PVC, w/w). The electrode exhibited a linear response with a near Nernstian slope of 19.5 mV/decade within the concentration range 1.5 x 10{sup -7}-1.0 x 10{sup -2} M terbium ions, with a working pH range from 2.0 to 8.0, and a fast response time of 10 s and presented satisfactory reproducibility. The limit of detection was 9.3 x 10{sup -8} M. The results show that this electrode can be used in ethanol media up to 30% (v/v) concentration without interference. It can be used for 3 months without any considerable divergence in the potentials. Selectivity coefficients for terbium(III) with respect to many cations were investigated. The electrode is highly selective for terbium(III) ions over a large number of monovalent, bivalent, and trivalent cations. This shows the valuable property of the proposed electrode. The stability constant of the ionophore towards Tb{sup 3+} ions was determined with the sandwich membrane method. It was successfully used as an indicator electrode in potentiometric determination of terbium(III) ions with EDTA and in direct determination in tap water and binary mixtures with quantitative results. The utility of the proposed electrode was also determined in the presence of ionic and nonionic surfactants and in the presence of fluoride ions in four pharmaceutical (mouthwash) preparations. (orig.)

Electroanalytical performance of a terbium(III)-selective sensor based on a neutral ionophore in environmental and medicinal samples

International Nuclear Information System (INIS)

Gupta, V.K.; Singh, A.K.; Gupta, Barkha

2008-01-01

A new highly selective terbium(III) electrode was prepared with a polymeric film doped using S-2-benzothiazolyl-2-amino-α-(methoxyimino)-4-thiazolethiol acetate as an electroactive material, benzyl acetate (BA) as a plasticizer, and potassium tetrakis(4-chlorophenyl) borate (KTpClPB) as an anionic site in the percentage ratio 3.17:1.58:63.4:31.7 (ionophore-KTpClPB-BA-PVC, w/w). The electrode exhibited a linear response with a near Nernstian slope of 19.5 mV/decade within the concentration range 1.5 x 10 -7 -1.0 x 10 -2 M terbium ions, with a working pH range from 2.0 to 8.0, and a fast response time of 10 s and presented satisfactory reproducibility. The limit of detection was 9.3 x 10 -8 M. The results show that this electrode can be used in ethanol media up to 30% (v/v) concentration without interference. It can be used for 3 months without any considerable divergence in the potentials. Selectivity coefficients for terbium(III) with respect to many cations were investigated. The electrode is highly selective for terbium(III) ions over a large number of monovalent, bivalent, and trivalent cations. This shows the valuable property of the proposed electrode. The stability constant of the ionophore towards Tb 3+ ions was determined with the sandwich membrane method. It was successfully used as an indicator electrode in potentiometric determination of terbium(III) ions with EDTA and in direct determination in tap water and binary mixtures with quantitative results. The utility of the proposed electrode was also determined in the presence of ionic and nonionic surfactants and in the presence of fluoride ions in four pharmaceutical (mouthwash) preparations. (orig.)

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.

A terbium(III)-organic framework for highly selective sensing of cytidine triphosphate.

Science.gov (United States)

Zhao, Xi Juan; He, Rong Xing; Li, Yuan Fang

2012-11-21

Highly selective sensing of cytidine triphosphate (CTP) against other triphosphate nucleosides including ATP, GTP and UTP is successfully achieved with a luminescent terbium(III)-organic framework (TbOF) of [Tb(2)(2,3-pzdc)(2)(ox)(H(2)O)(2)](n) (2,3-pzdc(2-) = 2,3-pyrazinedicarboxylate, ox(2-) = oxalate).

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

Raman spectra of terbium trichloride, phosphorus pentachloride and their molten mixtures

International Nuclear Information System (INIS)

Salyulev, A.B.; Zakir'yanova, I.D.

2008-01-01

Raman spectroscopy was used to study in situ the behavior of individual terbium trichloride and phosphorus pentachloride in different aggregative states as a function of temperature, and of solutions of PCl 5 vapors in molten TbCl 3 . A conclusion is drawn about their structure and the nature of phase transformations and chemical reactions in wide ranges of temperature and saturated vapor pressures [ru

Efficient green luminescence of terbium oxalate crystals: A case study with Judd-Ofelt theory and single crystal structure analysis and the effect of dehydration on luminescence

Science.gov (United States)

Alexander, Dinu; Joy, Monu; Thomas, Kukku; Sisira, S.; Biju, P. R.; Unnikrishnan, N. V.; Sudarsanakumar, C.; Ittyachen, M. A.; Joseph, Cyriac

2018-06-01

Design and synthesis of Lanthanide based metal organic framework is a frontier area of research owing to their structural diversity enabling specific applications. The luminescence properties of rare earths, tuned by the structural features of Ln-MOFs are investigated extensively. Rare earth oxalates which can be synthesized in a facile method, ensuring the structural features of MOFs with excellent photoluminescence characteristics deserves much attention. This work is the first time report on the single crystal structure and Judd-Ofelt (JO) theoretical analysis - their correlation with the intense and sharp green luminescence of Terbium oxalate crystals. The intense green luminescence observed for Terbium oxalate crystals for a wide range of excitation from DUV to visible region despite the luminescence limiting factors are discussed. The absence of concentration quenching and lifting up of forbidden nature of f-f transitions, allowing direct excitation of Terbium ions is analysed with the help of JO theory and single crystal structure analysis. The JO analysis predicted the asymmetry of Terbium sites, allowing the electric dipole transitions and from the JO intensity parameters, promising spectroscopic parameters - emission cross section, branching ratio, gain band width and gain coefficient of the material were calculated. The single crystal structure analysis revealed the asymmetry of Tb sites and structure of Terbium oxalate is formed by the hydrogen bonded stacking of overlapped six Terbium membered rings connected by the oxalate ligands. The molecularly thick layers thus formed on the crystal surface are imaged by the atomic force microscopy. The presence of water channels in the structure and the effect of lattice water molecules on the luminescence intensity are also investigated.

Spectrofluorimetric determination of cefixime using terbium-danofloxacin probe

Directory of Open Access Journals (Sweden)

Jamshid L Manzoori

2014-04-01

Full Text Available Objective(s:Cefixime (Cfx, is a semi-synthetic third-generation oral cephalosporin antibiotic that is prescribed for the treatment of susceptible infections. There are some procedures for the determination of Cfx in pharmaceutical formulations and biological samples. Herein a spectrofluorimetric method was proposed for Cfx determination based on the fluorescence quenching of terbium-danofloxacin (Tb3+-Dano in the presence of Cfx. Materials and Methods: Cfx was detected based on fluorescence quenching of terbium-danofloxacin (Tb3+-Dano in the presence of Cfx with maximum excitation and emission wavelengths at 347 nm and 545 nm, respectively. The quenched fluorescence intensity of Tb3+- Dano system is proportional to the concentration of Cfx. The optimum conditions for the determination of Cfx were studied. Results: The maximum response was achieved under optimum conditions of [Tris buffer]= 0.008 mol/l (pH 6.5, [Tb3+]=1×10-4 mol/l  and [Dano]=1×10-4 mol/l. The developed method was evaluated in terms of accuracy, precision and limit of detection. The linear concentration ranges for quantification of Cfx were 8.8×10-8-8.8×10-7 mol/l and 1.1×10-7-8.8×10-7 mol/l in standard and human serum samples with the detection limits (S/N=3 of 2.8×10-8 mol/l and 3.9×10-8 mol/l, respectively. The Cfx was determined in pharmaceutical tablets and spiked serum samples and the results were satisfactory.   Conclusion: This method is simple, practical and relatively interference-free for determination of Cfx in pharmaceutical tablets and serum samples.

Synthesis of Tb_4O_7 complexed with reduced graphene oxide for Rhodamine-B absorption

International Nuclear Information System (INIS)

Gao, Hui; Zhou, Yang; Chen, Keqin; Li, Xiaolong

2016-01-01

Highlights: • Tb–rGO composite was fabricated via a facile thermally reduction process. • The green and blue emissions were both observed in the composite. • The composite exhibited efficient absorption capability for Rhodamine-B. - Abstract: Tb_4O_7 complexed with reduced graphene oxide composite (Tb–rGO) had been designed and fabricated by a facile thermal reduction method. The formation of Tb_4O_7 particles and reduction of graphene oxide (GO) occurred simultaneously, and partial terbium ions would be complexed with rGO via oxygen-containing function groups on rGO sheets. Introducing of terbium ions could effectively tune the photoluminescence properties of rGO, and the composite exhibited the typical green emission of terbium ions as well as the blue self-luminescence of graphene entered at 440 nm. Moreover, Tb–rGO had demonstrated its high capability as an organic dye (Rhodamine-B) scavenger with high speed and efficiency. The findings showed the promising applications for large-scale removal of organic dye contaminants, especially in the field of waste water treatment.

{alpha}-particle induced reactions on yttrium and terbium

Energy Technology Data Exchange (ETDEWEB)

Mukherjee, S.; Kumar, B.B. [School of Studies in Physics, Vikram University, Ujjain-456010 (India); Rashid, M.H. [Variable Energy Cyclotron Center, 1/AF, Bidhan Nagar, Calcutta (India); Chintalapudi, S.N. [Inter-University Consortium for DAE Facilities, 3/LB, Bidhan Nagar, Calcutta (India)

1997-05-01

The stacked foil activation technique has been employed for the investigation of {alpha}-particle induced reactions on the target elements yttrium and terbium up to 50 MeV. Six excitation functions for the ({alpha},xn) type of reactions were studied using high-resolution HPGe {gamma}-ray spectroscopy. A comparison with Blann{close_quote}s geometric dependent hybrid model has been made using the initial exciton number n{sub 0}=4(4p0h) and n{sub 0}=5(5p0h). A broad general agreement is observed between the experimental results and theoretical predictions with an initial exciton number n{sub 0}=4(4p0h). {copyright} {ital 1997} {ital The American Physical Society}

α-particle induced reactions on yttrium and terbium

International Nuclear Information System (INIS)

Mukherjee, S.; Kumar, B.B.; Rashid, M.H.; Chintalapudi, S.N.

1997-01-01

The stacked foil activation technique has been employed for the investigation of α-particle induced reactions on the target elements yttrium and terbium up to 50 MeV. Six excitation functions for the (α,xn) type of reactions were studied using high-resolution HPGe γ-ray spectroscopy. A comparison with Blann close-quote s geometric dependent hybrid model has been made using the initial exciton number n 0 =4(4p0h) and n 0 =5(5p0h). A broad general agreement is observed between the experimental results and theoretical predictions with an initial exciton number n 0 =4(4p0h). copyright 1997 The American Physical Society

A thermoluminescence study of Z2-centres in terbium-doped NaCl crystals

International Nuclear Information System (INIS)

Reddy, K.N.; Ahmed, I.M.; Pandaraiah, N.; Rao, U.V.S.; Babu, V.H.

1983-01-01

Thermoluminescence (TL), optical absorption are used to correlate thermal annealing of Z 2 -centres with TL peak occurring around 110 0 C in terbium-doped NaCl crystals. The TL glow peak occurring around 190 0 C is attributed to the thermal annealing of F-centres. The thermal activation parameters are calculated for both Z 2 - and F-centre peaks. (author)

Synthesis of Tb{sub 4}O{sub 7} complexed with reduced graphene oxide for Rhodamine-B absorption

Energy Technology Data Exchange (ETDEWEB)

Gao, Hui, E-mail: hope@lzu.edu.cn [School of Physical Science and Technology, Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Zhou, Yang; Chen, Keqin [School of Physical Science and Technology, Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Li, Xiaolong, E-mail: lixiaolong@sinap.ac.cn [Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204 (China)

2016-05-15

Highlights: • Tb–rGO composite was fabricated via a facile thermally reduction process. • The green and blue emissions were both observed in the composite. • The composite exhibited efficient absorption capability for Rhodamine-B. - Abstract: Tb{sub 4}O{sub 7} complexed with reduced graphene oxide composite (Tb–rGO) had been designed and fabricated by a facile thermal reduction method. The formation of Tb{sub 4}O{sub 7} particles and reduction of graphene oxide (GO) occurred simultaneously, and partial terbium ions would be complexed with rGO via oxygen-containing function groups on rGO sheets. Introducing of terbium ions could effectively tune the photoluminescence properties of rGO, and the composite exhibited the typical green emission of terbium ions as well as the blue self-luminescence of graphene entered at 440 nm. Moreover, Tb–rGO had demonstrated its high capability as an organic dye (Rhodamine-B) scavenger with high speed and efficiency. The findings showed the promising applications for large-scale removal of organic dye contaminants, especially in the field of waste water treatment.

A Terbium Sensitized Luminescence Method for the Assay of Flubiprofen in Pharmaceutical Formulations

Directory of Open Access Journals (Sweden)

Salma M.Z. Al-Kindy

2014-12-01

Full Text Available A sensitive time-resolved luminescence method for the determination of flubiprofen (FLP in methanol and in aqueous solution is described. The method is based on the luminescence sensitization of terbium (Tb3+ by the formation of a ternary complex with FLP in the presence of 4,7 diphenyl 1,10 phenanthroline (DPP as co-ligand, and Tween-20 as surfactant. The signal for Tb-FLP-DPP was monitored at λex  = 285 nm and λem  = 552 nm. Optimum conditions for the formation of the complex in an aqueous system were TRIS buffer, pH 8.0, DPP (2.5Å~10−7  M, Tween-20 (0.30% and 4Å~10-5  mol L-1  of Tb3+  which allowed the determination of 20–1000 ng mL-1  of FLP with a limit of detection (LOD of 10 ng mL-1 . The relative standard deviations of the method ranged between 0.6 and 1.4% indicating excellent reproducibility of the method. The proposed method was successfully applied for the assays of FLP in pharmaceutical formulations and spiked tap water samples with average recoveries of 87% – 95%.

A hydrometallurgical process for the recovery of terbium from fluorescent lamps: Experimental design, optimization of acid leaching process and process analysis.

Science.gov (United States)

Innocenzi, Valentina; Ippolito, Nicolò Maria; De Michelis, Ida; Medici, Franco; Vegliò, Francesco

2016-12-15

Terbium and rare earths recovery from fluorescent powders of exhausted lamps by acid leaching with hydrochloric acid was the objective of this study. In order to investigate the factors affecting leaching a series of experiments was performed in according to a full factorial plan with four variables and two levels (4 2 ). The factors studied were temperature, concentration of acid, pulp density and leaching time. Experimental conditions of terbium dissolution were optimized by statistical analysis. The results showed that temperature and pulp density were significant with a positive and negative effect, respectively. The empirical mathematical model deducted by experimental data demonstrated that terbium content was completely dissolved under the following conditions: 90 °C, 2 M hydrochloric acid and 5% of pulp density; while when the pulp density was 15% an extraction of 83% could be obtained at 90 °C and 5 M hydrochloric acid. Finally a flow sheet for the recovery of rare earth elements was proposed. The process was tested and simulated by commercial software for the chemical processes. The mass balance of the process was calculated: from 1 ton of initial powder it was possible to obtain around 160 kg of a concentrate of rare earths having a purity of 99%. The main rare earths elements in the final product was yttrium oxide (86.43%) following by cerium oxide (4.11%), lanthanum oxide (3.18%), europium oxide (3.08%) and terbium oxide (2.20%). The estimated total recovery of the rare earths elements was around 70% for yttrium and europium and 80% for the other rare earths. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of intramolecular f-f interactions on nuclear spin driven quantum tunneling of magnetizations in quadruple-decker phthalocyanine complexes containing two terbium or dysprosium magnetic centers.

Science.gov (United States)

Fukuda, Takamitsu; Matsumura, Kazuya; Ishikawa, Naoto

2013-10-10

Nuclear spin driven quantum tunneling of magnetization (QTM) phenomena, which arise from admixture of more than two orthogonal electronic spin wave functions through the couplings with those of the nuclear spins, are one of the important magnetic relaxation processes in lanthanide single molecule magnets (SMMs) in the low temperature range. Although recent experimental studies have indicated that the presence of the intramolecular f-f interactions affects their magnetic relaxation processes, little attention has been given to their mechanisms and, to the best of our knowledge, no rational theoretical models have been proposed for the interpretations of how the nuclear spin driven QTMs are influenced by the f-f interactions. Since quadruple-decker phthalocyanine complexes with two terbium or dysprosium ions as the magnetic centers show moderate f-f interactions, these are appropriate to investigate the influence of the f-f interactions on the dynamic magnetic relaxation processes. In the present paper, a theoretical model including ligand field (LF) potentials, hyperfine, nuclear quadrupole, magnetic dipolar, and the Zeeman interactions has been constructed to understand the roles of the nuclear spins for the QTM processes, and the resultant Zeeman plots are obtained. The ac susceptibility measurements of the magnetically diluted quadruple-decker monoterbium and diterbium phthalocyanine complexes, [Tb-Y] and [Tb-Tb], have indicated that the presence of the f-f interactions suppresses the QTMs in the absence of the external magnetic field (H(dc)) being consistent with previous reports. On the contrary, the faster magnetic relaxation processes are observed for [Tb-Tb] than [Tb-Y] at H(dc) = 1000 Oe, clearly demonstrating that the QTMs are rather enhanced in the presence of the external magnetic field. Based on the calculated Zeeman diagrams, these observations can be attributed to the enhanced nuclear spin driven QTMs for [Tb-Tb]. At the H(dc) higher than 2000 Oe, the

Structure, magnetic behavior, and anisotropy of homoleptic trinuclear lanthanoid 8-quinolinolate complexes.

Science.gov (United States)

Chilton, Nicholas F; Deacon, Glen B; Gazukin, Olga; Junk, Peter C; Kersting, Berthold; Langley, Stuart K; Moubaraki, Boujemaa; Murray, Keith S; Schleife, Frederik; Shome, Mahasish; Turner, David R; Walker, Julia A

2014-03-03

Three complexes of the form [Ln(III)3(OQ)9] (Ln = Gd, Tb, Dy; OQ = 8-quinolinolate) have been synthesized and their magnetic properties studied. The trinuclear complexes adopt V-shaped geometries with three bridging 8-quinolinolate oxygen atoms between the central and peripheral eight-coordinate metal atoms. The magnetic properties of these three complexes differ greatly. Variable-temperature direct-current (dc) magnetic susceptibility measurements reveal that the gadolinium and terbium complexes display weak antiferromagnetic nearest-neighbor magnetic exchange interactions. This was quantified in the isotropic gadolinium case with an exchangecoupling parameter of J = -0.068(2) cm(-1). The dysprosium compound displays weak ferromagnetic exchange. Variable-frequency and -temperature alternating-current magnetic susceptibility measurements on the anisotropic cases reveal that the dysprosium complex displays single-molecule-magnet behavior, in zero dc field, with two distinct relaxation modes of differing time scales within the same molecule. Analysis of the data revealed anisotropy barriers of Ueff = 92 and 48 K for the two processes. The terbium complex, on the other hand, displays no such behavior in zero dc field, but upon application of a static dc field, slow magnetic relaxation can be observed. Ab initio and electrostatic calculations were used in an attempt to explain the origin of the experimentally observed slow relaxation of the magnetization for the dysprosium complex.

Autofluorescence-Free Live-Cell Imaging Using Terbium Nanoparticles.

Science.gov (United States)

Cardoso Dos Santos, M; Goetz, J; Bartenlian, H; Wong, K-L; Charbonnière, L J; Hildebrandt, N

2018-04-18

Fluorescent nanoparticles (NPs) have become irreplaceable tools for advanced cellular and subcellular imaging. While very bright NPs require excitation with UV or visible light, which can create strong autofluorescence of biological components, NIR-excitable NPs without autofluorescence issues exhibit much lower brightness. Here, we show the application of a new type of surface-photosensitized terbium NPs (Tb-NPs) for autofluorescence-free intracellular imaging in live HeLa cells. The combination of exceptionally high brightness, high photostability, and long photoluminecence (PL) lifetimes for highly efficient suppression of the short-lived autofluorescence allowed for time-gated PL imaging of intracellular vesicles over 72 h without toxicity and at extremely low Tb-NP concentrations down to 12 pM. Detection of highly resolved long-lifetime (ms) PL decay curves from small (∼10 μm 2 ) areas within single cells within a few seconds emphasized the unprecedented photophysical properties of Tb-NPs for live-cell imaging that extend well beyond currently available nanometric imaging agents.

Resonance energy transfer from quinolinone modified polystyrene-block-poly(styrene-alt-maleic anhydride) copolymer to terbium(III) metal ions

Czech Academy of Sciences Publication Activity Database

Výprachtický, Drahomír; Mikeš, F.; Lokaj, Jan; Pokorná, Veronika; Cimrová, Věra

2015-01-01

Roč. 160, April (2015), s. 27-34 ISSN 0022-2313 R&D Projects: GA ČR GAP106/12/0827; GA ČR(CZ) GA13-26542S Institutional support: RVO:61389013 Keywords : energy transfer * terbium luminescence * quinolinone donor Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.693, year: 2015

Preparation of transparent sol-gel films containing europium, terbium, and ytterbium cations from 4-(3'-triethoxysilylpropylimino)pent-2-en-2-ol

International Nuclear Information System (INIS)

Semenov, V.V.; Cherepennikova, N.F.; Kuznetsova, O.V.; Melenskova, N.V.; Bushuk, B.A.; Bushuk, S.B.; Kal'vinkovskaya, Yu.A.; Duglas, V.E.

2007-01-01

A reaction of 3-aminopropyl(triethoxy)silane with acetylacetone gave a mixture of two isomeric carbon-functionalized organosilicon compounds capable of complexation and sol-gel polymerization. These were 4-(3'-triethoxysilylpropylimino)pent-2-en-2-ol (EtO) 3 Si-CH 2 CH 2 CH 2 -N=C(Me)CH=C(Me)OH (Ia, 83%) and 4-(3'-triethoxysilylpropylamino)pent-3-en-2-one (EtO) 3 Si-CH 2 CH 2 CH 2 -NH-C(Me)=CH-C(O)Me (Ib, 17%). With acetylacetone trimethylsilyl ether instead of acetylacetone itself, compound Ia and silylated derivatives (Me 3 SiO) n (EtO) 3-n Si-CH 2 CH 2 CH 2 -N=C(Me)CH=C(Me)OH were obtained as admixture in 84 and 16% yields, respectively. Reactions of ligands Ia and Ib with europium and terbium propan-2-olates afforded the corresponding complexes. Formulations of lanthanide complexes, oligodimethylsiloxanediols, and 3-aminopropyl(triethoxy)silane were used to prepare transparent sol-gel films. The photoluminescence spectra of the films show narrow bands due to Eu 3+ or Tb 3+ emission. Emission from the organosilicon matrix appears as a broad band at 430 to 435 nm [ru

Magnetoresistance in terbium and holmium single crystals

International Nuclear Information System (INIS)

Singh, R.L.; Jericho, M.H.; Geldart, D.J.W.

1976-01-01

The longitudinal magnetoresistance of single crystals of terbium and holmium metals in their low-temperature ferromagnetic phase has been investigated in magnetic fields up to 80 kOe. Typical magnetoresistance isotherms exhibit a minimum which increases in depth and moves to higher fields as the temperature increases. The magnetoresistance around 1 0 K, where inelastic scattering is negligible, has been interpreted as the sum of a negative contribution due to changes in the domain structure and a positive contribution due to normal magnetoresistance. At higher temperatures, a phenomenological approach has been developed to extract the inelastic phonon and spin-wave components from the total measured magnetoresistance. In the temperature range 4--20 0 K (approximately), the phonon resistivity varies as T 3 . 7 for all samples. Approximate upper and lower bounds have been placed on the spin-wave resistivity which is also found to be described by a simple power law in this temperature range. The implications of this result for theoretical treatments of spin-wave resistivity due to s-f exchange interactions are considered. It is concluded that the role played by the magnon energy gap is far less transparent than previously suggested

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.

Compact all-fiber optical Faraday components using 65-wt%-terbium-doped fiber with a record Verdet constant of -32 rad/(Tm).

Science.gov (United States)

Sun, L; Jiang, S; Marciante, J R

2010-06-07

A compact all-fiber Faraday isolator and a Faraday mirror are demonstrated. At the core of each of these components is an all-fiber Faraday rotator made of a 4-cm-long, 65-wt%-terbium-doped silicate fiber. The effective Verdet constant of the terbium-doped fiber is measured to be -32 rad/(Tm), which is 27 x larger than that of silica fiber. This effective Verdet constant is the largest value measured to date in any fiber and is 83% of the Verdet constant of commercially available crystal used in bulk optics-based isolators. Combining the all-fiber Faraday rotator with fiber polarizers results in a fully fusion spliced all-fiber isolator whose isolation is measured to be 19 dB. Combining the all-fiber Faraday rotator with a fiber Bragg grating results in an all-fiber Faraday mirror that rotates the polarization state of the reflected light by 88 +/- 4 degrees .

Origin of gigantic magnetostriction and crystal field effects in terbium dititanate

International Nuclear Information System (INIS)

Aleksandrov, I.V.; Lidskij, B.V.; Mamsurova, L.G.

1985-01-01

The temperature and magnetic field dependences of the magnetostriction and magnetization and the temperature dependences of the magnetic susceptibility, specific heat and lattice parameter are investigated experimentally in a broad range of temperature and field strength for polycrystalline and single crystal Tb 2 Ti 2 O 7 . A conclusion is drawn regarding the structure of the energy levels of Tb 3+ in Tb 2 Ti 2 O 7 . A qualitative and quantitative explanation of all observed magnetic effects, and in particular of gigantic magnetostriction in Tb 2 Ti 2 O 7 , is presented which is based on the crystal field theory. It is shown that the huge magnitude of the magnetostriction in terbium dititanate is due to the specificity of the energy spectrum of Tb 3+ in Tb 2 Ti 2 O 7

Electronic structure of surface-supported bis(phthalocyaninato) terbium(III) single molecular magnets.

Science.gov (United States)

Vitali, Lucia; Fabris, Stefano; Conte, Adriano Mosca; Brink, Susan; Ruben, Mario; Baroni, Stefano; Kern, Klaus

2008-10-01

The electronic structure of isolated bis(phthalocyaninato) terbium(III) molecules, a novel single-molecular-magnet (SMM), supported on the Cu(111) surface has been characterized by density functional theory and scanning tunneling spectroscopy. These studies reveal that the interaction with the metal surface preserves both the molecular structure and the large spin magnetic moment of the metal center. The 4f electron states are not perturbed by the adsorption while a strong molecular/metal interaction can induce the suppression of the minor spin contribution delocalized over the molecular ligands. The calculations show that the inherent spin magnetic moment of the molecule is only weakly affected by the interaction with the surface and suggest that the SMM character might be preserved.

Folate Receptor Targeted Alpha-Therapy Using Terbium-149

CERN Document Server

Müller, Cristina; Haller, Stephanie; Dorrer, Holger; Köster, Ulli; Johnston, Karl; Zhernosekov, Konstantin; Türler, Andreas; Schibli, Roger

2014-01-01

Terbium-149 is among the most interesting therapeutic nuclides for medical applications. It decays by emission of short-range α-particles (Eα = 3.967 MeV) with a half-life of 4.12 h. The goal of this study was to investigate the anticancer efficacy of a 149Tb-labeled DOTA-folate conjugate (cm09) using folate receptor (FR)-positive cancer cells in vitro and in tumor-bearing mice. 149Tb was produced at the ISOLDE facility at CERN. Radiolabeling of cm09 with purified 149Tb resulted in a specific activity of ~1.2 MBq/nmol. In vitro assays performed with 149Tb-cm09 revealed a reduced KB cell viability in a FR-specific and activity concentration-dependent manner. Tumor-bearing mice were injected with saline only (group A) or with 149Tb-cm09 (group B: 2.2 MBq; group C: 3.0 MBq). A significant tumor growth delay was found in treated animals resulting in an increased average survival time of mice which received 149Tb-cm09 (B: 30.5 d; C: 43 d) compared to untreated controls (A: 21 d). Analysis of blood parameters rev...

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.

Complex logic functions implemented with quantum dot bionanophotonic circuits.

Science.gov (United States)

Claussen, Jonathan C; Hildebrandt, Niko; Susumu, Kimihiro; Ancona, Mario G; Medintz, Igor L

2014-03-26

We combine quantum dots (QDs) with long-lifetime terbium complexes (Tb), a near-IR Alexa Fluor dye (A647), and self-assembling peptides to demonstrate combinatorial and sequential bionanophotonic logic devices that function by time-gated Förster resonance energy transfer (FRET). Upon excitation, the Tb-QD-A647 FRET-complex produces time-dependent photoluminescent signatures from multi-FRET pathways enabled by the capacitor-like behavior of the Tb. The unique photoluminescent signatures are manipulated by ratiometrically varying dye/Tb inputs and collection time. Fluorescent output is converted into Boolean logic states to create complex arithmetic circuits including the half-adder/half-subtractor, 2:1 multiplexer/1:2 demultiplexer, and a 3-digit, 16-combination keypad lock.

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.

Hyperfine structure of the odd parity level system in the terbium atom

International Nuclear Information System (INIS)

Stefanska, D; Furmann, B

2017-01-01

Within this work new experimental results concerning the hyperfine structure ( hfs ) in the terbium atom are presented, concerning the odd parity levels system, hitherto only scarcely investigated (apart from the ground term). hfs constants A and B for 113 levels were determined for the first time, and for another 16 levels, which already occurred in our earlier works, supplementary results were obtained; additionally, our earlier results for 93 levels were compiled. The hfs of the odd parity levels was investigated using the method of laser induced fluorescence in a hollow cathode discharge. The hfs of 165 spectral lines, where the levels in question were involved as the upper levels, was recorded. Literature values of hfs constants of the even-parity lower levels (including our own earlier results) greatly facilitated the present data evaluation. (paper)

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.

Terbium fluorescence as a sensitive, inexpensive probe for UV-induced damage in nucleic acids

International Nuclear Information System (INIS)

El-Yazbi, Amira F.; Loppnow, Glen R.

2013-01-01

Graphical abstract: -- Highlights: •Simple, inexpensive, mix-and-read assay for positive detection of DNA damage. •Recognition of undamaged DNA via hybridization to a hairpin probe. •Terbium(III) fluorescence reports the amount of damage by binding to ssDNA. •Tb/hairpin is a highly selective and sensitive fluorescent probe for DNA damage. -- Abstract: Much effort has been focused on developing methods for detecting damaged nucleic acids. However, almost all of the proposed methods consist of multi-step procedures, are limited, require expensive instruments, or suffer from a high level of interferences. In this paper, we present a novel simple, inexpensive, mix-and-read assay that is generally applicable to nucleic acid damage and uses the enhanced luminescence due to energy transfer from nucleic acids to terbium(III) (Tb 3+ ). Single-stranded oligonucleotides greatly enhance the Tb 3+ emission, but duplex DNA does not. With the use of a DNA hairpin probe complementary to the oligonucleotide of interest, the Tb 3+ /hairpin probe is applied to detect ultraviolet (UV)-induced DNA damage. The hairpin probe hybridizes only with the undamaged DNA. However, the damaged DNA remains single-stranded and enhances the intrinsic fluorescence of Tb 3+ , producing a detectable signal directly proportional to the amount of DNA damage. This allows the Tb 3+ /hairpin probe to be used for sensitive quantification of UV-induced DNA damage. The Tb 3+ /hairpin probe showed superior selectivity to DNA damage compared to conventional molecular beacons probes (MBs) and its sensitivity is more than 2.5 times higher than MBs with a limit of detection of 4.36 ± 1.2 nM. In addition, this probe is easier to synthesize and more than eight times cheaper than MBs, which makes its use recommended for high-throughput, quantitative analysis of DNA damage

Synthesis and crystal structure of terbium(III) meta-oxoborate Tb(BO{sub 2}){sub 3} ({identical_to} TbB{sub 3}O{sub 6}); Synthese und Kristallstruktur von Terbium(III)-meta-Oxoborat Tb(BO{sub 2}){sub 3} ({identical_to} TbB{sub 3}O{sub 6})

Energy Technology Data Exchange (ETDEWEB)

Nikelski, Tanja; Schleid, Thomas [Institut fuer Anorganische Chemie der Universitaet Stuttgart (Germany)

2003-06-01

The terbium meta-oxoborate Tb(BO{sub 2}){sub 3} ({identical_to} TbB{sub 3}O{sub 6}) is obtained as single crystals by the reaction of terbium, Tb{sub 4}O{sub 7} and TbCl{sub 3} with an excess of B{sub 2}O{sub 3} in gastight sealed platinum ampoules at 950 C after three weeks. The compound appears to be air- and water-resistant and crystallizes as long, thin, colourless needles which tend to growth-twinning due to their marked fibrous habit. The crystal structure of Tb(BO{sub 2}){sub 3} (orthorhombic, Pnma; a = 1598.97(9), b = 741.39(4), c = 1229.58(7) pm; Z = 16) contains strongly corrugated oxoborate layers {sub {infinity}}{sup 2}{l_brace}(BO{sub 2}){sup -}{r_brace} built of vertex-linked [BO{sub 4}]{sup 5-} tetrahedra (d(B-O) = 143 - 154 pm, and angsph;(O-B-O) = 102-115 ) which spread out parallel (100). The four crystallographically different Tb{sup 3+} cations all exhibit coordination numbers of eight towards the oxygen atoms (d(Tb-O) = 228-287 pm). The corresponding metal cation polyhedra [TbO{sub 8}]{sup 13+} too convene to layers (composition: {sub {infinity}}{sup 2}{l_brace}(Tb{sub 2}O{sub 11}){sup 16-}{r_brace}) which are likewise oriented parallel to the (100) plane. (Abstract Copyright [2003], Wiley Periodicals, Inc.) [German] Das Terbium-meta-Oxoborat Tb(BO{sub 2}){sub 3} ({identical_to} TbB{sub 3}O{sub 6}) entsteht einkristallin bei der Reaktion von Terbium, Tb{sub 4}O{sub 7} und TbCl{sub 3} mit einem Ueberschuss von B{sub 2}O{sub 3} in gasdicht verschlossenen Platinampullen nach drei Wochen bei 950 C. Die Verbindung ist luft- und wasserstabil und faellt in langen, duennen, farblosen Nadeln an, die aufgrund ihres ausgepraegt faserigen Habitus zur Wachstumsverzwillingung neigen. Die Kristallstruktur von Tb(BO{sub 2}){sub 3} (orthorhombisch, Pnma; a = 1598, 97(9), b = 741, 39(4), c = 1229, 58(7) pm; Z = 16) enthaelt parallel (100) verlaufende, stark gewellte Oxoborat-Schichten {sub {infinity}}{sup 2}{l_brace}(BO{sub 2}){sup -}{r_brace} aus

Luminescent properties of terbium complexes with catecholamines and their application in analysis

International Nuclear Information System (INIS)

Kravchenko, T.B.; Bel'tyukova, S.V.; Kononenko, L.I.; Poluehktov, N.S.

1982-01-01

Tb complexing with a representative of catecholamines - adrenaline - is studied using the luminescence method. It is found, that the complexing takes place in alkaline medium (pH 12.0). To prevent from compound oxidation with air oxygen and to create the necessary pH in solution sodium borohydride is used. The highest luminescence intensity is achieved when the reaction occurs in aqueous-isopropanol solutions. It is established that in the complexes formed the ratio of components is the following: Tb:adrenaline=1:3. Luminescent properties of Tb complex with adrenaline are used to determine the latter. The least detectable amount of adrenaline constitutes 0.02 μg, the determination error does not exceed 5.5% [ru

Monoxides of small terbium clusters: A density functional theory investigation

Energy Technology Data Exchange (ETDEWEB)

Zhang, G. L.; Yuan, H. K., E-mail: yhk10@swu.edu.cn; Chen, H.; Kuang, A. L.; Li, Y.; Wang, J. Z.; Chen, J. [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China)

2014-12-28

To investigate the effect of oxygen atom on the geometrical structures, electronic, and magnetic properties of small terbium clusters, we carried out the first-principles calculations on Tb{sub n}O (n = 1-14) clusters. The capping of an oxygen atom on one trigonal-facet of Tb{sub n} structures is always favored energetically, which can significantly improve the structural stability. The far-infrared vibrational spectroscopies are found to be different from those of corresponding bare clusters, providing a distinct signal to detect the characteristic structures of Tb{sub n}O clusters. The primary effect of oxygen atom on magnetic properties is to change the magnetic orderings among Tb atoms and to reduce small of local magnetic moments of the O-coordinated Tb atoms, both of which serve as the key reasons for the experimental magnetic evolution of an oscillating behavior. These calculations are consistent with, and help to account for, the experimentally observed magnetic properties of monoxide Tb{sub n}O clusters [C. N. Van Dijk et al., J. Appl. Phys. 107, 09B526 (2010)].

Evaluating United States and world consumption of neodymium, dysprosium, terbium, and praseodymium in final products

Science.gov (United States)

Hart, Matthew

This paper develops scenarios of future rare-earth-magnet metal (neodymium, dysprosium, terbium, and praseodymium) consumption in the permanent magnets used in wind turbines and hybrid electric vehicles. The scenarios start with naive base-case scenarios for growth in wind-turbine and hybrid-electric-vehicle sales over the period 2011 to 2020, using historical data for each good. These naive scenarios assume that future growth follows time trends in historical data and does not depend on any exogenous variable. Specifically, growth of each technological market follows historical time trends, and the amount of rare earths used per unit of technology remains fixed. The chosen reference year is 2010. Implied consumptions of the rare earth magnet metals are calculated from these scenarios. Assumptions are made for the material composition of permanent magnets, the market share of permanent-magnet wind turbines and vehicles, and magnet weight per unit of technology. Different scenarios estimate how changes in factors like the material composition of magnets, growth of the economy, and the price of a substitute could affect future consumption. Each scenario presents a different method for reducing rare earth consumption and could be interpreted as potential policy choices. In 2010, the consumption (metric tons, rare-earth-oxide equivalent) of each rare-earth-magnet metal was as follows. Total neodymium consumption in the world for both technologies was 995 tons; dysprosium consumption was 133 tons; terbium consumption was 50 tons; praseodymium consumption was zero tons. The base scenario for wind turbines shows there could be strong, exponential growth in the global wind turbine market. New U.S. sales of hybrid vehicles would decline (in line with the current economic recession) while non-U.S. sales increase through 2020. There would be an overall increase in the total amount of magnetic rare earths consumed in the world. Total consumption of each rare earth in the short

Determination of sertraline in pharmaceutical and biological samples using 1, 10-phenanthroline-terbium probe and silver nanoparticles enhanced fluorescence

Energy Technology Data Exchange (ETDEWEB)

Lotfi, Ali, E-mail: alilotfi67@gmail.com [Young Researchers and Elite Club, Tabriz Branch, Islamic Azad University, Tabriz (Iran, Islamic Republic of); Manzoori, Jamshid L. [Department of Chemistry, Tabriz Branch, Islamic Azad University, Tabriz (Iran, Islamic Republic of); Mohagheghi, Arash [Clinical Psychiatry Research Center, Tabriz University of Medical Sciences, Tabriz (Iran, Islamic Republic of)

2017-05-15

Sertraline is an antidepressant widely prescribed for major depressive disorders. In this contribution we report a novel, rapid and sensitive spectrofluorimetric technique, developed and validated for the determination of sertraline in pharmaceutical, human urine and human plasma samples, based on the fluorescence enhancement of the sertraline by 1, 10-phenanthroline-terbium probe with Ag nanoparticles (AgNPs). The effect of pH, buffer concentration, the order of addition of reagents, terbium and 1, 10-phenanthroline concentrations, and concentration of Ag nanoparticles (AgNPs) as well as reaction time on the fluorescence intensity were investigated and the optimum conditions were determined. The linear range for determination of sertraline was obtained as 0.001–3 mg L{sup −1}. The limit of detection (b+3s) and the limit of quantification was calculated as 2.9×10{sup −4} mg L{sup −1} and 9.8×10{sup −4} mg L{sup −1}, respectively. The interference effects of common excipients found in pharmaceutical preparations were studied. The presented technique was used to determine the sertraline in pharmaceutical samples, human urine and plasma as real samples. The presented method was indicated a comparable results with the standard analytical techniques for sertraline. Good linearity, reproducibility, recovery and limit of detection have made this method suitable for determination of sertraline in various types of samples.

Determination of sertraline in pharmaceutical and biological samples using 1, 10-phenanthroline-terbium probe and silver nanoparticles enhanced fluorescence

International Nuclear Information System (INIS)

Lotfi, Ali; Manzoori, Jamshid L.; Mohagheghi, Arash

2017-01-01

Sertraline is an antidepressant widely prescribed for major depressive disorders. In this contribution we report a novel, rapid and sensitive spectrofluorimetric technique, developed and validated for the determination of sertraline in pharmaceutical, human urine and human plasma samples, based on the fluorescence enhancement of the sertraline by 1, 10-phenanthroline-terbium probe with Ag nanoparticles (AgNPs). The effect of pH, buffer concentration, the order of addition of reagents, terbium and 1, 10-phenanthroline concentrations, and concentration of Ag nanoparticles (AgNPs) as well as reaction time on the fluorescence intensity were investigated and the optimum conditions were determined. The linear range for determination of sertraline was obtained as 0.001–3 mg L −1 . The limit of detection (b+3s) and the limit of quantification was calculated as 2.9×10 −4 mg L −1 and 9.8×10 −4 mg L −1 , respectively. The interference effects of common excipients found in pharmaceutical preparations were studied. The presented technique was used to determine the sertraline in pharmaceutical samples, human urine and plasma as real samples. The presented method was indicated a comparable results with the standard analytical techniques for sertraline. Good linearity, reproducibility, recovery and limit of detection have made this method suitable for determination of sertraline in various types of samples.

Solid-phase synthesis of compounds of europium and terbium with nitrogen-containing heterocyclic compounds under mechanical activation

International Nuclear Information System (INIS)

Kalinovskaya, I.V.; Karasev, V.E.

2000-01-01

Effect of solvents and parameters of mechanical treatment on basic regularities of synthesis of rare earth compounds with nitrogen-containing heterocyclic compounds is studied. It is shown that interaction on europium (3) and terbium (3) nitrates with nitrogen-containing heterocyclic compounds leads to formation of compounds of Ln(NO 3 )·2D composition, where Ln=Eu, Tb; D=2,2-dipyridyl, 1,10-phenanthroline, diphenylguanidine. Effect of conditions of mechanical treatment and different additions on process and yield of products is studied. Compounds prepared are characterized by the methods of chemical element analysis, IR spectroscopy and luminescent spectroscopy [ru

Nanostructured Layered Terbium Hydroxide Containing NASIDs: In Vitro Physicochemical and Biological Evaluations.

Science.gov (United States)

Gu, Qing-Yang; Qiu, Xiao; Liu, Jing-Jing; Fu, Min; Chao, Jian-Ping; Ju, Rui-Jun; Li, Xue-Tao

2018-08-01

Diclofenac sodium (abrr. DS) and indomethacin (abrr. IMC) have been intercalated into the layered terbium hydroxide (LTbH) by anion exchange method. Chemical compositions, thermostability, morphology, luminescence property, release behaviors and cytotoxic effects have been investigated. The DS molecules may embed between layers with a bilayered arrangement and the IMC may correspond to a monolayered arrangement. The Tb3+ luminescence in DS-LTbH and IMC-LTbH composites were enhanced compared with LTbH precusor and the luminescence intensity increases with the deprotonation degree. Drug release was measured with HPLC, and LTbH showed sustained release behavior on both drugs. Further In Vitro evaluation were carried out on cancer cells. Cytotoxic effect of LTbH was observed with a sulforhodamine B colorimetric assay on a variety of cancer cell lines, which revealed that the LTbH showed little cytotoxic effect. Results indicate LTbH may offer a potential vehicle as an effective drug delivery system along with diagnostic integration.

Raman spectra of terbium trichloride, phosphorus pentachloride and their molten mixtures; Spektry kombinatsionnogo rasseyaniya sveta trikhlorida terbiya, pentakhlorida fosfora i ikh rasplavlennykh smesej

Energy Technology Data Exchange (ETDEWEB)

Salyulev, A B; Zakir' yanova, I D [UrO RAN, Inst. Vysokotemperaturnoj Ehlektrokhimii, Ekaterinburg (Russian Federation)

2008-03-15

Raman spectroscopy was used to study in situ the behavior of individual terbium trichloride and phosphorus pentachloride in different aggregative states as a function of temperature, and of solutions of PCl{sub 5} vapors in molten TbCl{sub 3}. A conclusion is drawn about their structure and the nature of phase transformations and chemical reactions in wide ranges of temperature and saturated vapor pressures.

Thermoluminescence of cerium and terbium -doped calcium pyrophosphate

Energy Technology Data Exchange (ETDEWEB)

Roman L, J.; Cruz Z, E. [UNAM, Instituto de Ciencias Nucleares, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Lozano R, I. B.; Diaz G, J. A. I., E-mail: jesus.roman@nucleares.unam.mx [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria No. 694, 11500 Mexico D. F. (Mexico)

2015-10-15

The aim of this work is to report the thermoluminescence (Tl) response of Calcium Pyrophosphate phosphor doped with Cerium and Terbium impurities (Ca{sub 2}P{sub 2}O{sub 7}:Ce{sup 3+},Tb{sup 3+}). The phosphors were synthesized using the co-precipitation method and annealed at 900 degrees C by two hours for obtain the β phase. The intentional doping with Ce and Tb ions was 1 at.% and 0.1 at.%, whereas in the EDS results the concentration of impurities was 0.39 at.% and 0.05 at.%, respectively. The superficial morphology of phosphor is mainly composed by thin wafers of different size. All samples were exposed to gamma rays from {sup 60}Co in the Gammacell-200 irradiator. The Tl response of the phosphor was measured from Rt up to 350 degrees C and under nitrogen atmosphere in a Harshaw TLD 3500 reader. The glow curves of the Ca{sub 2}P{sub 2}O{sub 7}:Ce{sup 3+},Tb{sup 3+} powders showed a broad intense Tl peak centered at 165 degrees C and a shoulder at approximate 260 degrees C was observed. A linear Tl response in the range of absorbed dose of 0.2 to 10 Gy was obtained. Tl glow curves were analyzed using the initial rise (IR)and computerized glow curve deconvolution methods to evaluate the kinetics parameters such as activation energy (E), frequency factor (s) and kinetic order (b). (Author)

Effects of time on the magnetic properties of terbium-doped LaMnO3

International Nuclear Information System (INIS)

Liu Weibin; Zhang Yingtang; Guan Wen; Kinsman, William; Yuan Xinqiang; Chen Ziyu

2012-01-01

The magnetic properties of the perovskite form of LaMnO 3 have been shown strong interest in recent years due to its high potential for use in magnetic devices. In this paper, the magnetic properties of a 30% terbium-doped LaMnO 3 (LMTO) perovskite manganite synthesized by a conventional solid-state reaction were investigated. Data on these properties was recorded periodically via SQUID and VSM to reveal it to be best described magnetically as a spin glass system. Thus, the time effect must be taken into consideration in instantaneously determining this material’s spin glass state as well as the overall magnetic properties in the absence of a magnetic field. The results of this paper point to a more in-depth understanding of the change in magnetic properties associated with doped LaMnO 3 .

Modelling of curium and americium behaviour during separation with displacing complexing chromatography

International Nuclear Information System (INIS)

Chuveleva, Eh.A.; Kharitonov, O.V.; Firsova, L.A.

1994-01-01

Certain heavy rare earths, curium and americium were separated by the method of displacement complexing chromatography using DTPA solutions and solutions containing DTPA and citric acid as eluents. Separation factors of rare earths and curium (americium) were calculated. Imitators for curium and americium separation were suggested: thulium for curium elution using 0.025 mol/l DTPA, holmium-for curium elution using 0.025 mol/l DTPA in the presence of 0.025 mol/l citric acid; terbium can serve as the imitator in both cases. 5 refs., 5 figs

Lanthanide complexes as luminogenic probes to measure sulfide levels in industrial samples

International Nuclear Information System (INIS)

Thorson, Megan K.; Ung, Phuc; Leaver, Franklin M.; Corbin, Teresa S.; Tuck, Kellie L.; Graham, Bim; Barrios, Amy M.

2015-01-01

A series of lanthanide-based, azide-appended complexes were investigated as hydrogen sulfide-sensitive probes. Europium complex 1 and Tb complex 3 both displayed a sulfide-dependent increase in luminescence, while Tb complex 2 displayed a decrease in luminescence upon exposure to NaHS. The utility of the complexes for monitoring sulfide levels in industrial oil and water samples was investigated. Complex 3 provided a sensitive measure of sulfide levels in petrochemical water samples (detection limit ∼ 250 nM), while complex 1 was capable of monitoring μM levels of sulfide in partially refined crude oil. - Highlights: • Lanthanide–azide based sulfide sensors were synthesized and characterized. • The probes have excitation and emission profiles compatible with sulfide-contaminated samples from the petrochemical industry. • A terbium-based probe was used to measure the sulfide concentration in oil refinery wastewater. • A europium-based probe had compatibility with partially refined crude oil samples.

Lanthanide complexes as luminogenic probes to measure sulfide levels in industrial samples

Energy Technology Data Exchange (ETDEWEB)

Thorson, Megan K. [Department of Medicinal Chemistry, University of Utah College of Pharmacy, Salt Lake City, UT 84108 (United States); Ung, Phuc [Monash Institute of Pharmaceutical Sciences, Monash University, Victoria 3052 (Australia); Leaver, Franklin M. [Water & Energy Systems Technology, Inc., Kaysville, UT 84037 (United States); Corbin, Teresa S. [Quality Services Laboratory, Tesoro Refining and Marketing, Salt Lake City, UT 84103 (United States); Tuck, Kellie L., E-mail: kellie.tuck@monash.edu [School of Chemistry, Monash University, Victoria 3800 (Australia); Graham, Bim, E-mail: bim.graham@monash.edu [Monash Institute of Pharmaceutical Sciences, Monash University, Victoria 3052 (Australia); Barrios, Amy M., E-mail: amy.barrios@utah.edu [Department of Medicinal Chemistry, University of Utah College of Pharmacy, Salt Lake City, UT 84108 (United States)

2015-10-08

A series of lanthanide-based, azide-appended complexes were investigated as hydrogen sulfide-sensitive probes. Europium complex 1 and Tb complex 3 both displayed a sulfide-dependent increase in luminescence, while Tb complex 2 displayed a decrease in luminescence upon exposure to NaHS. The utility of the complexes for monitoring sulfide levels in industrial oil and water samples was investigated. Complex 3 provided a sensitive measure of sulfide levels in petrochemical water samples (detection limit ∼ 250 nM), while complex 1 was capable of monitoring μM levels of sulfide in partially refined crude oil. - Highlights: • Lanthanide–azide based sulfide sensors were synthesized and characterized. • The probes have excitation and emission profiles compatible with sulfide-contaminated samples from the petrochemical industry. • A terbium-based probe was used to measure the sulfide concentration in oil refinery wastewater. • A europium-based probe had compatibility with partially refined crude oil samples.

Influence of crystallite size and temperature on the antiferromagnetic helices of terbium and holmium metal

Energy Technology Data Exchange (ETDEWEB)

Bick, Jens-Peter; Michels, Andreas [Universitaet des Saarlandes, D-66041 Saarbruecken (Germany); University of Luxembourg, L-1511 Luxembourg (Luxembourg); Ferdinand, Adrian; Birringer, Rainer [Universitaet des Saarlandes, D-66041 Saarbruecken (Germany); Baller, Joerg; Sanctuary, Roland [University of Luxembourg, L-1511 Luxembourg (Luxembourg); Philippi, Stefan [Leibniz Institute for Solid State and Materials Research, D-01069 Dresden (Germany); Lott, Dieter [GKSS Research Center, D-21502 Geesthacht (Germany); Balog, Sandor [Paul Scherrer Institute, CH-5232 Villigen (Switzerland); Rotenberg, Eli [Lawrence Berkeley National Laboratory, California 94720 (United States); Kaindl, Guenter [Freie Universitaet Berlin, D-14195 Berlin-Dahlem (Germany); Doebrich, Kristian M. [Freie Universitaet Berlin, D-14195 Berlin-Dahlem (Germany); Max-Born-Institut, D-12489 Berlin (Germany)

2011-07-01

We report on the results of grain-size and temperature-dependent magnetization, specific-heat, neutron-scattering, and angle-resolved photoelectron spectroscopy (ARPES) experiments on the heavy rare-earth metals terbium and holmium, with particular emphasis on the temperature regions where the helical antiferromagnetic phases exist. In contrast to Ho, we find that the helical structure in Tb is relative strongly affected by microstructural disorder, specifically, it can no longer be detected for the smallest studied grain size of D=18 nm. Moreover, in coarse-grained Tb a helical structure persists even in the ferromagnetic regime, down to about T=215 K, in agreement with the ARPES data, which reveal a nesting feature of the Fermi surface at the L point of the Brillouin zone at T=210 K.

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.

Terbium to Quantum Dot FRET Bioconjugates for Clinical Diagnostics: Influence of Human Plasma on Optical and Assembly Properties

Directory of Open Access Journals (Sweden)

Niko Hildebrandt

2011-10-01

Full Text Available Förster resonance energy transfer (FRET from luminescent terbium complexes (LTC as donors to semiconductor quantum dots (QDs as acceptors allows extraordinary large FRET efficiencies due to the long Förster distances afforded. Moreover, time-gated detection permits an efficient suppression of autofluorescent background leading to sub-picomolar detection limits even within multiplexed detection formats. These characteristics make FRET-systems with LTC and QDs excellent candidates for clinical diagnostics. So far, such proofs of principle for highly sensitive multiplexed biosensing have only been performed under optimized buffer conditions and interactions between real-life clinical media such as human serum or plasma and LTC-QD-FRET-systems have not yet been taken into account. Here we present an extensive spectroscopic analysis of absorption, excitation and emission spectra along with the luminescence decay times of both the single components as well as the assembled FRET-systems in TRIS-buffer, TRIS-buffer with 2% bovine serum albumin, and fresh human plasma. Moreover, we evaluated homogeneous LTC-QD FRET assays in QD conjugates assembled with either the well-known, specific biotin-streptavidin biological interaction or, alternatively, the metal-affinity coordination of histidine to zinc. In the case of conjugates assembled with biotin-streptavidin no significant interference with the optical and binding properties occurs whereas the histidine-zinc system appears to be affected by human plasma.

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).

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.

Effects of time on the magnetic properties of terbium-doped LaMnO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Liu Weibin [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Zhang Yingtang, E-mail: zhangyingtang76@mail.xjtu.edu.cn [School of Material Science and Engineering, Institute of Functional Material, Shaanxi University of Technology, Hanzhong 723003 (China); State Key Laboratory of Electrical Insulation and Power Equipment and MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi' an Jiaotong University, Xi' an 710049 (China); Guan Wen [State Key Laboratory of Electrical Insulation and Power Equipment and MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi' an Jiaotong University, Xi' an 710049 (China); Kinsman, William [Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 (United States); Yuan Xinqiang [School of Material Science and Engineering, Institute of Functional Material, Shaanxi University of Technology, Hanzhong 723003 (China); Chen Ziyu [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China)

2012-09-01

The magnetic properties of the perovskite form of LaMnO{sub 3} have been shown strong interest in recent years due to its high potential for use in magnetic devices. In this paper, the magnetic properties of a 30% terbium-doped LaMnO{sub 3} (LMTO) perovskite manganite synthesized by a conventional solid-state reaction were investigated. Data on these properties was recorded periodically via SQUID and VSM to reveal it to be best described magnetically as a spin glass system. Thus, the time effect must be taken into consideration in instantaneously determining this material's spin glass state as well as the overall magnetic properties in the absence of a magnetic field. The results of this paper point to a more in-depth understanding of the change in magnetic properties associated with doped LaMnO{sub 3}.

Induced assembly and photoluminescence of lanthanum (Tb, Eu, Dy) complexes/ZnO/polyethylene glycol hybrid phosphors

Energy Technology Data Exchange (ETDEWEB)

Yan Bing [Department of Chemistry, Tongji University, Siping Road 1239, Shanghai 200092 (China)]. E-mail: byan@tongji.edu.cn; Chen Xi [Department of Chemistry, Tongji University, Siping Road 1239, Shanghai 200092 (China); Wu Jianhua [Department of Chemistry, Tongji University, Siping Road 1239, Shanghai 200092 (China)

2007-08-31

Some novel kinds of hybrid phosphors were assembled with lanthanum (Tb, Eu, Dy) complexes (with four kinds of terbium complexes is 2,4-dihydroxybenzonic acid (DHBA), 1,10-phenanthroline (phen), acetylacetone (AA) and nicotinic acid (Nic), respectively) doped ZnO/PEG particles by co-precipitation approach derived from Zn(CH{sub 3}COO){sub 2} (Zn(AC){sub 2}), NaOH, PEG as precursors at room temperature. The characteristic luminescence spectra for f-f transitions of Tb{sup 3+}, Eu{sup 3+}, Dy{sup 3+} were observed. It is worthy to point out that ZnO is the excellent host for lanthanum ions by the assembly of PEG matrices.

Sensitivity improvement of Cerenkov luminescence endoscope with terbium doped Gd{sub 2}O{sub 2}S nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Cao, Xin; Chen, Xueli, E-mail: xlchen@xidian.edu.cn, E-mail: jimleung@mail.xidian.edu.cn; Cao, Xu; Zhan, Yonghua; Liang, Jimin, E-mail: xlchen@xidian.edu.cn, E-mail: jimleung@mail.xidian.edu.cn [Engineering Research Center of Molecular and Neuro Imaging of the Ministry of Education and School of Life Science and Technology, Xidian University, Xi' an, Shaanxi 710071 (China); Kang, Fei; Wang, Jing [Department of Nuclear Medicine, Xijing Hospital, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Wu, Kaichun [Department of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China)

2015-05-25

Our previous study showed a great attenuation for the Cerenkov luminescence endoscope (CLE), resulting in relatively low detection sensitivity of radiotracers. Here, a kind of radioluminescence nanoparticles (RLNPs), terbium doped Gd{sub 2}O{sub 2}S was mixed with the radionuclide {sup 68}Ga to enhance the intensity of emitted luminescence, which finally improved the detection sensitivity of the CLE by using the radioluminescence imaging technique. With the in vitro and in vivo pseudotumor experiments, we showed that the use of RLNPs mixed with the radionuclide {sup 68}Ga enabled superior sensitivity compared with the radionuclide {sup 68}Ga only, with 50-fold improvement on detection sensitivity, which guaranteed meeting the demands of the clinical diagnosis of gastrointestinal tract tumors.

Sonochemical synthesis of terbium tungstate for developing high power supercapacitors with enhanced energy densities.

Science.gov (United States)

Sobhani-Nasab, Ali; Rahimi-Nasrabadi, Mehdi; Naderi, Hamid Reza; Pourmohamadian, Vafa; Ahmadi, Farhad; Ganjali, Mohammad Reza; Ehrlich, Hermann

2018-07-01

Sonochemically prepared nanoparticles of terbium tungstate (TWNPs) were evaluated through scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR), UV-Vis spectroscopy, and the optimal products were further characterized in terms of their electrochemical properties using conventional and continuous cyclic voltammetry (CV, and CCV), galvanostatic charge/discharge technique, and electrochemical impedance spectroscopy (EIS). The CV studies indicated the TWNPs to have specific capacitance (SC) values of 336 and 205 F g -1 at 1 and 200 mV s -1 , and galvanostatic charge-discharge tests revealed the SC of the TWNP-based electrodes to be 300 F g -1 at 1 Ag -1 . Also continuous cyclic voltammetry evaluations proved the sample as having a capacitance retention value of 95.3% after applying 4000 potential cycles. In the light of the results TWNPs were concluded as favorable electrode materials for use in hybrid vehicle systems. Copyright © 2018 Elsevier B.V. All rights reserved.

Complete Stokes polarimetry of magneto-optical Faraday effect in a terbium gallium garnet crystal at cryogenic temperatures.

Science.gov (United States)

Majeed, Hassaan; Shaheen, Amrozia; Anwar, Muhammad Sabieh

2013-10-21

We report the complete determination of the polarization changes caused in linearly polarized incident light due to propagation in a magneto-optically active terbium gallium garnet (TGG) single crystal, at temperatures ranging from 6.3 to 300 K. A 28-fold increase in the Verdet constant of the TGG crystal is seen as its temperature decreases to 6.3 K. In contrast with polarimetry of light emerging from a Faraday material at room temperature, polarimetry at cryogenic temperatures cannot be carried out using the conventional fixed polarizer-analyzer technique because the assumption that ellipticity is negligible becomes increasingly invalid as temperature is lowered. It is shown that complete determination of light polarization in such a case requires the determination of its Stokes parameters, otherwise inaccurate measurements will result with negative implications for practical devices.

Luminescent materials based on Tb, Eu-containing layered double hydroxides

International Nuclear Information System (INIS)

Zhuravleva, N.G.; Eliseev, A.A.; Lukashin, A.V.; Kinast, U.; Tret'yakov, Yu.D.

2004-01-01

Luminescent materials on the basis of magnesium-aluminium layered double hydroxides with intercalated anionic complexes of terbium and europium picolinates were synthesized. Relying on data of spectroscopy, elementary and X-ray phase analyses, the change in the rare earth complex structure and metal/ligand ratio, depending on the hydroxide layer charge, determined by Mg/Al ratio in the double hydroxide, were ascertained. The values of quantum yields of luminescence for terbium-containing samples amounted to 30-50% [ru

Picomolar traces of americium(III) introduce drastic changes in the structural chemistry of terbium(III). A break in the ''gadolinium break''

Energy Technology Data Exchange (ETDEWEB)

Welch, Jan M. [TU Wien, Atominstitut, Vienna (Austria); Mueller, Danny; Knoll, Christian; Wilkovitsch, Martin; Weinberger, Peter [TU Wien, Institute of Applied Synthetic Chemistry, Vienna (Austria); Giester, Gerald [University of Vienna, Institute of Mineralogy and Crystallography, Vienna (Austria); Ofner, Johannes; Lendl, Bernhard [TU Wien, Institute of Chemical Technologies and Analytics, Vienna (Austria); Steinhauser, Georg [Leibniz Universitaet Hannover, Institute of Radioecology and Radiation Protection (Germany)

2017-10-16

The crystallization of terbium 5,5{sup '}-azobis[1H-tetrazol-1-ide] (ZT) in the presence of trace amounts (ca. 50 Bq, ca. 1.6 pmol) of americium results in 1) the accumulation of the americium tracer in the crystalline solid and 2) a material that adopts a different crystal structure to that formed in the absence of americium. Americium-doped [Tb(Am)(H{sub 2}O){sub 7}ZT]{sub 2} ZT.10 H{sub 2}O is isostructural to light lanthanide (Ce-Gd) 5,5{sup '}-azobis[1H-tetrazol-1-ide] compounds, rather than to the heavy lanthanide (Tb-Lu) 5,5{sup '}-azobis[1H-tetrazol-1-ide] (e.g., [Tb(H{sub 2}O){sub 8}]{sub 2}ZT{sub 3}.6 H{sub 2}O) derivatives. Traces of Am seem to force the Tb compound into a structure normally preferred by the lighter lanthanides, despite a 10{sup 8}-fold Tb excess. The americium-doped material was studied by single-crystal X-ray diffraction, vibrational spectroscopy, radiochemical neutron activation analysis, and scanning electron microscopy. In addition, the inclusion properties of terbium 5,5{sup '}-azobis[1H-tetrazol-1-ide] towards americium were quantified, and a model for the crystallization process is proposed. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

Solar Thermochemical Hydrogen Production via Terbium Oxide Based Redox Reactions

Directory of Open Access Journals (Sweden)

Rahul Bhosale

2016-01-01

Full Text Available The computational thermodynamic modeling of the terbium oxide based two-step solar thermochemical water splitting (Tb-WS cycle is reported. The 1st step of the Tb-WS cycle involves thermal reduction of TbO2 into Tb and O2, whereas the 2nd step corresponds to the production of H2 through Tb oxidation by water splitting reaction. Equilibrium compositions associated with the thermal reduction and water splitting steps were determined via HSC simulations. Influence of oxygen partial pressure in the inert gas on thermal reduction of TbO2 and effect of water splitting temperature (TL on Gibbs free energy related to the H2 production step were examined in detail. The cycle (ηcycle and solar-to-fuel energy conversion (ηsolar-to-fuel efficiency of the Tb-WS cycle were determined by performing the second-law thermodynamic analysis. Results obtained indicate that ηcycle and ηsolar-to-fuel increase with the decrease in oxygen partial pressure in the inert flushing gas and thermal reduction temperature (TH. It was also realized that the recuperation of the heat released by the water splitting reactor and quench unit further enhances the solar reactor efficiency. At TH=2280 K, by applying 60% heat recuperation, maximum ηcycle of 39.0% and ηsolar-to-fuel of 47.1% for the Tb-WS cycle can be attained.

Terbium(III)/gold nanocluster conjugates: the development of a novel ratiometric fluorescent probe for mercury(II) and a paper-based visual sensor.

Science.gov (United States)

Qi, Yan-Xia; Zhang, Min; Zhu, Anwei; Shi, Guoyue

2015-08-21

In this work, a novel ratiometric fluorescent probe was developed for rapid, highly accurate, sensitive and selective detection of mercury(II) (Hg(2+)) based on terbium(III)/gold nanocluster conjugates (Tb(3+)/BSA-AuNCs), in which bovine serum albumin capped gold nanoclusters (BSA-AuNCs) acted as the signal indicator and terbium(III) (Tb(3+)) was used as the build-in reference. Our proposed ratiometric fluorescent probe exhibited unique specificity toward Hg(2+) against other common environmentally and biologically important metal ions, and had high accuracy and sensitivity with a low detection limit of 1 nM. In addition, our proposed probe was effectively employed to detect Hg(2+) in the biological samples from the artificial Hg(2+)-infected rats. More significantly, an appealing paper-based visual sensor for Hg(2+) was designed by using filter paper embedded with Tb(3+)/BSA-AuNC conjugates, and we have further demonstrated its feasibility for facile fluorescent sensing of Hg(2+) in a visual format, in which only a handheld UV lamp is used. In the presence of Hg(2+), the paper-based visual sensor, illuminated by a handheld UV lamp, would undergo a distinct fluorescence color change from red to green, which can be readily observed with naked eyes even in trace Hg(2+) concentrations. The Tb(3+)/BSA-AuNC-derived paper-based visual sensor is cost-effective, portable, disposable and easy-to-use. This work unveiled a facile approach for accurate, sensitive and selective measuring of Hg(2+) with self-calibration.

Preparation and luminescence properties of terbium-doped lanthanum oxide nanofibers by electrospinning

Energy Technology Data Exchange (ETDEWEB)

Song Lixin; Du Pingfan [Key Laboratory of Advanced Textile Materials and Manufacturing Technology (Zhejiang Sci-Tech University), Ministry of Education, Hangzhou 310018 (China); Xiong Jie, E-mail: jxiong@zstu.edu.cn [Key Laboratory of Advanced Textile Materials and Manufacturing Technology (Zhejiang Sci-Tech University), Ministry of Education, Hangzhou 310018 (China); Fan Xiaona; Jiao Yuxue [Key Laboratory of Advanced Textile Materials and Manufacturing Technology (Zhejiang Sci-Tech University), Ministry of Education, Hangzhou 310018 (China)

2012-01-15

Terbium-doped lanthanum oxide (La{sub 2}O{sub 3}:Tb{sup 3+}) nanofibers were prepared by electrospinning followed by calcination at high temperature. Thermogravimetric analyzer (TGA), field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and photoluminescence (PL) were used to characterize the obtained fibers. The results reveal that the nanofibers have an average diameter of ca. 95{+-}25 nm and are composed of pure La{sub 2}O{sub 3} phase. Under the excitation of 274 nm light, the La{sub 2}O{sub 3}:Tb{sup 3+} nanofibers exhibit the characteristic emission resulting from the {sup 5}D{sub 4}{yields}{sup 7}F{sub J} (J=3, 4, 5, 6) transitions of Tb{sup 3+} ions. And the PL emission intensity is stronger than that of their nanoparticle counterparts. - Highlights: > Tb{sup 3+}-doped La{sub 2}O{sub 3} (La{sub 2}O{sub 3}:Tb{sup 3+}) fluorescent nanofibers were prepared via a simple electrospinning technique. > Luminescent properties and other characteristics of the nanofibers were investigated in details. > Potential applications of La{sub 2}O{sub 3}:Tb{sup 3+} nanofibers and electrospinning technique described in this paper are suggested.

Fluorometric determination of proteins using the terbium (III)-2-thenoyltrifluoroacetone-sodium dodecyl benzene sulfonate-protein system

Energy Technology Data Exchange (ETDEWEB)

Jia Zhen [Key Laboratory of Colloid and Interface Chemistry of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Department of Chemistry, Dezhou University, Dezhou 253023 (China); Yang Jinghe [Key Laboratory of Colloid and Interface Chemistry of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)]. E-mail: yjh@sdu.edu.cn; Wu Xia [Key Laboratory of Colloid and Interface Chemistry of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Wang Fei [Key Laboratory of Colloid and Interface Chemistry of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Guo Changying [Key Laboratory of Colloid and Interface Chemistry of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Liu Shufang [Key Laboratory of Colloid and Interface Chemistry of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

2006-12-15

It is found that in hexamethylene tetramine (HMTA)-HCl buffer of pH=8.00, proteins can enhance the fluorescence of terbium (III) (Tb{sup 3+})-2-thenoyltrifluoroacetone (TTA)-sodium dodecyl benzene sulfonate (SDBS) system. Based on this, a sensitive method for the determination of proteins is proposed. The experiments indicate that under the optimum conditions, the enhanced fluorescence intensity is in proportion to the concentration of proteins in the range of 4.0x10{sup -9}-7.5x10{sup -6}g/mL for bovine serum albumin (BSA), 5.0x10{sup -9}-1.5x10{sup -5}g/mL for human serum albumin (HSA), 1.0x10{sup -8}-7.5x10{sup -6}g/mL for egg albumin (EA). Their detection limits (S/N=3) are 0.5, 0.8 and 2.0ng/mL, respectively. The interaction mechanism is also studied.

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.

A search for long-lived radionuclides produced by fast-neutron irradiations of copper, silver, europium, terbium, and hafnium

International Nuclear Information System (INIS)

Meadows, J.W.; Smith, D.L.; Ikeda, Y.; Konno, C.

1990-01-01

Identical sample packets, each containing samples of elemental copper, silver, europium, terbium, and hafnium, as well as titanium, iron and nickel as dosimeters, have been irradiated in three distinct accelerator neutron fields (at Argonne National Laboratory and Los Alamos National Laboratory in the U.S.A., and Japan Atomic Energy Research Institute, Tokai, Japan) as part of an interlaboratory research collaboration to search for the production of long-lived radionuclides for fusion waste disposal applications. This paper is a progress report on this project. To date, we have detected the following activities, and have obtained preliminary experimental cross section values for several of these: Ag-106m,108m,110m; Eu-150m,152g,154; Tb-158,160; and Hf-175,178m2,179m2,181. (author). 11 refs, 1 fig., 4 tabs

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)

Evidence of mass exchange between inside and outside of sonoluminescing bubble in aqueous solution of terbium chloride

Energy Technology Data Exchange (ETDEWEB)

Liang, Jinfu, E-mail: liang.shi2007@163.com [School of Physics and Electronic Science, Guizhou Normal University, Guiyang 550001 (China); Chen, Weizhong, E-mail: wzchen@nju.edu.cn [The Key Laboratory of Modern Acoustics, Ministry of Education, Institution of Acoustics, Nanjing University, Nanjing 210093 (China); Wang, Xun; Yang, Jing; Chen, Zhan [The Key Laboratory of Modern Acoustics, Ministry of Education, Institution of Acoustics, Nanjing University, Nanjing 210093 (China)

2016-12-16

Highlights: • Time-resolved spectra of SBSL were obtained for Tb{sup 3+} ions emission lines. • Mass exchange between inside and outside of SL bubble was probed via Tb{sup 3+} ions lines. • The argon rectification hypothesis was tested by time-resolved spectra of SBSL. • The rate of mass exchange inside an SBSL bubble increases with increasing sound pressure. - Abstract: Spectra of single-bubble sonoluminescence (SBSL) were obtained for Tb{sup 3+} ions emission lines from bubbles in an aqueous solution of terbium chloride (TbCl{sub 3}). The spectra provide experimental evidence to prove that an air bubble driven by strong ultrasound will not eventually become a rectified pure argon bubble, which is not as predicted by the argon rectification hypothesis. The time-resolved spectra of SBSL show a mass exchange of material such as Tb{sup 3+} ions between the inside and outside of the bubble. With increasing sound pressure, the rate of mass exchange and the SBSL intensity increases.

High power single-frequency and frequency-doubled laser with active compensation for the thermal lens effect of terbium gallium garnet crystal.

Science.gov (United States)

Yin, Qiwei; Lu, Huadong; Su, Jing; Peng, Kunchi

2016-05-01

The thermal lens effect of terbium gallium garnet (TGG) crystal in a high power single-frequency laser severely limits the output power and the beam quality of the laser. By inserting a potassium dideuterium phosphate (DKDP) slice with negative thermo-optical coefficient into the laser resonator, the harmful influence of the thermal lens effect of the TGG crystal can be effectively mitigated. Using this method, the stable range of the laser is broadened, the bistability phenomenon of the laser during the process of changing the pump power is completely eliminated, the highest output power of an all-solid-state continuous-wave intracavity-frequency-doubling single-frequency laser at 532 nm is enhanced to 30.2 W, and the beam quality of the laser is significantly improved.

The inverse-trans-influence in tetravalent lanthanide and actinide bis(carbene) complexes

Science.gov (United States)

Gregson, Matthew; Lu, Erli; Mills, David P.; Tuna, Floriana; McInnes, Eric J. L.; Hennig, Christoph; Scheinost, Andreas C.; McMaster, Jonathan; Lewis, William; Blake, Alexander J.; Kerridge, Andrew; Liddle, Stephen T.

2017-02-01

Across the periodic table the trans-influence operates, whereby tightly bonded ligands selectively lengthen mutually trans metal-ligand bonds. Conversely, in high oxidation state actinide complexes the inverse-trans-influence operates, where normally cis strongly donating ligands instead reside trans and actually reinforce each other. However, because the inverse-trans-influence is restricted to high-valent actinyls and a few uranium(V/VI) complexes, it has had limited scope in an area with few unifying rules. Here we report tetravalent cerium, uranium and thorium bis(carbene) complexes with trans C=M=C cores where experimental and theoretical data suggest the presence of an inverse-trans-influence. Studies of hypothetical praseodymium(IV) and terbium(IV) analogues suggest the inverse-trans-influence may extend to these ions but it also diminishes significantly as the 4f orbitals are populated. This work suggests that the inverse-trans-influence may occur beyond high oxidation state 5f metals and hence could encompass mid-range oxidation state actinides and lanthanides. Thus, the inverse-trans-influence might be a more general f-block principle.

Commercializing potassium terbium fluoride, KTF (KTb3F10) faraday crystals for high laser power optical isolator applications

Science.gov (United States)

Schlichting, Wolfgang; Stevens, Kevin; Foundos, Greg; Payne, Alexis

2017-10-01

Many scientific lasers and increasingly industrial laser systems operate in manufacture. However, for high-power laser applications TGG is limited by its absorption at 1064nm and its thermo-optic coefficient, dn/dT. Specifically, thermal lensing and depolarization effects become a limiting factor at high laser powers. While TGG absorption has improved significantly over the past few years, there is an intrinsic limit. Now, SYNOPTICS is commercializing the enhanced new crystal Potassium Terbium Fluoride KTF (KTb3F10) that exhibits much smaller nonlinear refractive index and thermo-optic coefficients, and still exhibits a Verdet constant near that of TGG. This cubic crystal has relatively low absorption and thermo-optic coefficients. It is now fully characterized and available for select production orders. At OPTIFAB in October 2017 we present recent results comparing the performance of KTF to TGG in optical isolators and show SYNOPTICS advances in large volume crystal growth and the production ramp up.

Synthesis, characterization and properties of novel amide derivatives based open-chain crown ether and their Tb (III) complexes

International Nuclear Information System (INIS)

Liu, Yanhong; He, Wei; Yang, Zehui; Chen, Yanwen; Wang, Xinwei; Guo, Dongcai

2015-01-01

Six amide-based open-chain crown ether and their solid complexes with terbium nitrates were synthesized. The target complexes were characterized by elemental analysis, mass spectra, EDTA titrimetric analysis, thermal analysis, molar conductivity, infrared spectra and UV–vis spectra. Luminescence properties of the ligands and the corresponding complexes in solid were studied. The results showed that the introduction of electron-donating group to the ligand enhanced the luminescence intensity of the corresponding complex, but electron-withdrawing group conversely. Meanwhile, among all complexes, the luminescence quantum yield of the complex Tb(NO 3 ) 3 Y 1 was highest up to 0.76. Electrochemical properties were also investigated, and the results showed that the introduction of electron-donating group to the ligand enhanced the highest occupied molecular orbit (HOMO) and the lowest unoccupied molecular orbit (LUMO) energy level, but electron-withdrawing group conversely. And these target complexes may possibly be useful for studying in organic light-emitting devices field. - Highlights: • Novel amide derivatives based open-chain crown ether and their Tb (III) complexes were prepared and characterized. • The target complexes presented high thermodynamic stability. • Influence of the substituent on luminescence intensity and electrochemical property were discussed

Direct two-photon excitation of Sm3+, Eu3+, Tb3+, Tb.DOTA-, and Tb.propargylDO3A in solution

Science.gov (United States)

Sørensen, Thomas Just; Blackburn, Octavia A.; Tropiano, Manuel; Faulkner, Stephen

2012-07-01

We have observed direct two-photon excitation of samarium, europium and terbium ions in solution upon near IR excitation using a tuneable pulsed light source, and have also studied two-photon processes in a pair of related terbium complexes, namely [Tb.DOTA]- and Tb.propargylDO3A. Direct two-photon excitation of lanthanides is observed in simple systems in the absence of sensitizing chromophores. Where even simple chromophores such as a triple bond are present in the complex, then single and two-photon excitation of chromophore excited states competes with direct two-photon excitation of the ions and is the dominant pathway for sensitizing formation of the lanthanide excited state.

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.

An ICP AES method for determination of dysprosium and terbium in high purity yttrium oxide

International Nuclear Information System (INIS)

Rupawate, V.H.; Hareendran, K.N.; Roy, S.B.

2011-01-01

High purity yttrium finds interesting application in astronavigation, luminescence, nuclear energy and metallurgical industries. Most of these applications require yttrium oxide of highest purity. Consequently there is a need for production of high purity yttrium oxide. Separation and purification of yttrium from other rare earths is a challenging task due to their close chemical properties. Liquid-liquid extraction and ion exchange have been widely used in the production of yttrium oxide of highest purity. Determination of impurities, especially other rare earths, in ppm level is required for process development and chemical characterization of the high purity Y 2 O 3 . Many methods have been described in literature. However since the advent of ICP AES much work in this area has been carried out by this technique. This paper describes the work done for determination of dysprosium (Dy) and terbium (Tb) in yttrium oxide using a high resolution sequential ICP AES. Emission spectra of rare earth elements are very complex and due to this complexity it is important to select spectral interference free analyte lines for determination of rare earths in rare earth matrix. For the determination of Dy and Tb in Y 2 O 3 , sensitive lines of Dy and Tb are selected from the instrument wavelength table and spectral interference free emission lines for the determination is selected by scanning around the selected wavelengths using 5 g/L Y solution and 5 mg/L standard solutions of Dy and Tb prepared in 4% nitric acid. It is found 353.170 nm line of Dy and 350.917 nm line Tb is suitable for quantitative determination. The signal to background ratio increases with increase in matrix concentration, i.e. from 1 to 5 mg/L. The optimum forward power is determined and it is found to be 1100W for Dy and 1000W for Tb. The instrument is calibrated using matrix matched standards containing 5g/L of Y matrix. Samples are dissolved in nitric acid and Y concentration is maintained at 5g/L. Two

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.

Preparation of three terbium complexes with p-aminobenzoic acid and investigation of crystal structure influence on luminescence property

International Nuclear Information System (INIS)

Ye Chaohong; Sun Haoling; Wang Xinyi; Li Junran; Nie Daobo; Fu Wenfu; Gao Song

2004-01-01

Three new rare earth p-aminobenzoic acid complexes, [Tb 2 L 6 (H 2 O) 2 ] n (1), [Tb 2 L 6 (H 2 O) 4 ].2H 2 O (2) and [Tb(phen) 2 L 2 (H 2 O) 2 ](phen)L·4H 2 O (3) (HL: p-aminobenzoic acid; phen: 1, 10-phenanthroline), with different structural forms are reported in this paper. Complex 1 is a polymolecule with a two-dimensional plane structure. Compound 2 is a binuclear molecule, and 3 appears to be a mononuclear complex. The fluorescence intensity, the fluorescence life-time and emission quantum yield of 2, which has two coordination water molecules, is better than those of 1, which has only one coordination water molecule. This is an unusual phenomenon for general fluorescent rare earth complexes. The fluorescence performance of 3 is the most unsatisfactory among the three complexes. Their crystal structures show that the coordination mode of the ligand is an important factor influencing the luminescence properties of a fluorescent rare earth complex

Studies of binary cerium(IV)-praseodymium(IV) and cerium(IV)-terbium(IV) oxides as pigments for ceramic applications

International Nuclear Information System (INIS)

Furtado, L.M.L.

1991-01-01

It was investigated a series of pigments of general composition Ce 1-x Pr x O 2 , and Ce x Tb y O 2 , exhibiting radish and brown colors, respectively, and high temperature stability. The pigments were obtained by dissolving appropriate amounts of the pure lanthanide oxides in acids and precipitating the rare earths as mixed oxalates, which were isolated and calcined under air, at 1000 0 C. X-Ray powder diffractograms were consistent with a cubic structure for the pigments. Magnetic susceptibility measurements, using Gouy method, indicated the presence of Pr(IV) ions in the Ce 1-x Pr x O 2 pigments and of Terbium predominantly as Tb(III) ions in the Ce-tb mixed oxides. A new method, based on suspension of solid samples in PVA-STB gels (STB = sodium tetradecaborate), was employed for the measurements of the electronic spectra of the pigments. The thermal behaviour the pigments was investigated by the calcination of the oxalates in the temperature range of 500 to 1200 O C, from 10 to 60 minutes. (author)

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)

Study for the determination of samarium, europium,terbium, dysprosium and yttrium in gadolinium oxide matrix by means of atomic absorption spectrophotometry using a graphite furnace

International Nuclear Information System (INIS)

Caires, A.C.F.

1985-01-01

A study for determination of samarium, europium, terbium, dysprosium and yttrium in a gadolinium oxide matrix by atomic absorption spectrophotometry using a graphite furnace is presented. The best charrring and atomization conditions were estabilished for each element, the most convenient ressonance lines being selected as well. The study was carried out for the mentioned lanthanides both when pure and when in binary mixtures with gadolinium, besides those where all for them were together with gadolinium. The determination limits for pure lanthanides were found to be between 1.3 and 9.6 ng assuming a 20% relative standard deviation as acceptable. The detection limits were in the range 0.51 and 7.5 ng, assuming as positive any answer higher than twofold the standard deviation. (author) [pt

VUV and UV–vis optical study on KGd2F7 luminescent host doped with terbium and co-doped with europium

International Nuclear Information System (INIS)

Lisiecki, Radosław

2013-01-01

The KGd 2 F 7 :Tb and KGd 2 F 7 :Tb,Eu samples were obtained using a solid state reaction. Excitation spectra and emission spectra are reported and analyzed within the VUV–UV–vis spectral range. The intense green luminescence is observed in the KGd 2 F 7 :Tb while the combined emission of terbium and europium in the KGd 2 F 7 :Tb,Eu covers substantially the region of white light. The materials under study can be effectively excited making use of intense f–d transitions of Tb 3+ in the VUV–UV region. Experimental lifetimes of luminescent levels have been measured and discussed. It was found that the considerable energy transfer from Tb 3+ to Eu 3+ occurs. -- Highlights: • The prospective green and white emitting phosphors. • The effective VUV and UV–vis excitation process. • The considerable energy transfer among optically active ions. • The influence of (Tb, Eu) co-doping on relaxation dynamic of excited states

Structural, elastic, mechanical and thermodynamic properties of Terbium oxide: First-principles investigations

Directory of Open Access Journals (Sweden)

Samah Al-Qaisi

Full Text Available First-principles investigations of the Terbium oxide TbO are performed on structural, elastic, mechanical and thermodynamic properties. The investigations are accomplished by employing full potential augmented plane wave FP-LAPW method framed within density functional theory DFT as implemented in the WIEN2k package. The exchange-correlation energy functional, a part of the total energy functional, is treated through Perdew Burke Ernzerhof scheme of the Generalized Gradient Approximation PBEGGA. The calculations of the ground state structural parameters, like lattice constants a0, bulk moduli B and their pressure derivative B′ values, are done for the rock-salt RS, zinc-blende ZB, cesium chloride CsCl, wurtzite WZ and nickel arsenide NiAs polymorphs of the TbO compound. The elastic constants (C11, C12, C13, C33, and C44 and mechanical properties (Young’s modulus Y, Shear modulus S, Poisson’s ratio σ, Anisotropic ratio A and compressibility β, were also calculated to comprehend its potential for valuable applications. From our calculations, the RS phase of TbO compound was found strongest one mechanically amongst the studied cubic structures whereas from hexagonal phases, the NiAs type structure was found stronger than WZ phase of the TbO. To analyze the ductility of the different structures of the TbO, Pugh’s rule (B/SH and Cauchy pressure (C12–C44 approaches are used. It was found that ZB, CsCl and WZ type structures of the TbO were of ductile nature with the obvious dominance of the ionic bonding while RS and NiAs structures exhibited brittle nature with the covalent bonding dominance. Moreover, Debye temperature was calculated for both cubic and hexagonal structures of TbO in question by averaging the computed sound velocities. Keywords: DFT, TbO, Elastic properties, Thermodynamic properties

Kinetically inert lanthanide complexes as reporter groups for binding of potassium by 18-crown-6

DEFF Research Database (Denmark)

Junker, Anne Kathrine Ravnsborg; Tropiano, Manuel; Faulkner, Stephen

2016-01-01

in a copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) “click” reaction with azide-functionalized crown ethers. The resulting complexes were investigated using NMR and optical methods. Titrations with potassium chloride in methanol observing the sensititzed europium- and terbium-centered emissions were......-centered emission to report on the binding of potassium in an 18-crown-6 binding pocket. The responsive systems were made by linking a crown ether to a kinetically inert lanthanide binding pocket using a molecular building block approach. Specifically, an alkyne-appended Ln.DO3A was used as a building block...... used to investigate the response of the systems. The molecular reporters based on aliphatic crown ethers were found to have strongly inhibited binding of potassium, while the benzo-18-crown-6 derived systems had essentially the same association constants as the native crown ethers. The shape...

Complexes of DOTA-bisphosphonate conjugates: probes for determination of adsorption capacity and affinity constants of hydroxyapatite.

Science.gov (United States)

Vitha, Tomas; Kubícek, Vojtech; Hermann, Petr; Kolar, Zvonimir I; Wolterbeek, Hubert Th; Peters, Joop A; Lukes, Ivan

2008-03-04

The adsorption on hydroxyapatite of three conjugates of a bisphosphonate and a macrocycle having C1, C2, and C3 spacers and their terbium complexes was studied by the radiotracer method using 160Tb as the label. The radiotracer-containing complex of the conjugate with the C3 spacer was used as a probe for the determination of the adsorption parameters of other bisphosphonates that lack a DOTA unit. A physicochemical model describing the competitive adsorption was successfully applied in the fitting of the obtained data. The maximum adsorption capacity of bisphosphonates containing bulky substituents is determined mainly by their size. For bisphosphonates having no DOTA moiety, the maximum adsorption capacity is determined by the electrostatic repulsion between negatively charged bisphosphonate groups. Compounds with a hydroxy or amino group attached to the alpha-carbon atom show higher affinities. Macrocyclic compounds containing a short spacer between the different bisphosphonic acid groups and the macrocyclic unit exhibit high affinities, indicating a synergic effect of the bisphosphonic and the macrocyclic groups during adsorption. The competition method described uses a well-characterized complex and allows a simple evaluation of the adsorption behavior of bisphosphonates. The application of the macrocycle-bisphosphonate conjugates allows easy radiolabeling via complexation of a suitable metal isotope.

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

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

Development and Validation of A Spectrofluorimetric Determination of Calf Thymus DNA Using a Terbium-Danofloxacin Probe

Directory of Open Access Journals (Sweden)

Naser Soltani

2016-03-01

Full Text Available Background: Analysis of biomolecules is required in many biomedical research areas. A spectrofluorimetric method is proposed for determination of calf thymus DNA (ctDNA based on the fluorescence enhancement of terbium-danofloxacin (Tb3+-Dano in the presence of ctDNA. Methods: A probe with maximum excitation and emission wavelengths of 347 nm and 545 nm, respectively, was developed. The enhanced fluorescence intensity of Tb3+-Dano system was proportional to the concentration of ctDNA. The effective factors and the optimum conditions for the determination of ctDNA were studied. Under the optimum conditions of [Tris buffer]= 0.01 mol L-1 (pH 7.8, [ Tb3+]= 1×10-5 mol L-1 and [Dano]= 5×10-5 mol L-1, the maximum response was achieved. The developed method was evaluated in terms of accuracy, precision and limit of detection. Results: The linear concentration range for quantification of ctDNA was 36-3289 ng mL-1 and the detection limit (S/N=3 was 8 ng mL-1. The concentration of DNA extracted from Escherichia coli as an extracted sample was also determined using the developed probe. The concentration of DNA in extracted sample was determined using UV assay and developed method, the results were satisfactory. Conclusion: The proposed method is a simple, practical and relatively interference free method to follow up the concentrations of ctDNA.

Investigation of concentration-dependence of thermodynamic properties of lanthanum, yttrium, scandium and terbium in eutectic LiCl-KCl molten salt

Energy Technology Data Exchange (ETDEWEB)

Wang, Yafei; Zhou, Wentao; Zhang, Jinsuo, E-mail: zhang.3558@osu.edu

2016-09-15

Thermodynamic properties of rare earth metals in LiCl-KCl molten salt electrolyte are crucial to the development of electrochemical separation for the treatment of used nuclear fuels. In the present study, activity coefficient, apparent potential, and diffusion coefficient of lanthanum, yttrium, scandium, and terbium in the molten salt (58 at% LiCl and 42 at% KCl) were calculated by the method of molecular dynamics simulation up to a concentration around 3 at% at temperatures of 723 K and 773 K. It was found that the activity coefficient and the apparent potential increase with the species concentration while diffusion coefficient shows a trend of increase followed by decrease. The calculated results were validated by available measurement data of dilution cases. This research extends the range of data to a wide component and would provide further insight to the pyroprocessing design and safeguards. - Highlights: • Investigation of activity coefficient, apparent potential and diffusion coefficient at different concentrations. • MD simulation was studied for the calculation of thermodynamic properties of rare earth elements in molten salt. • The present study is a pioneering work focusing on the concentration dependence of thermodynamic properties.

Determination of terbium in phosphate rock by Tb{sup 3+}-selective fluorimetric optode based on dansyl derivative as a neutral fluorogenic ionophore

Energy Technology Data Exchange (ETDEWEB)

Hosseini, Morteza, E-mail: smhosseini@khayam.ut.ac.ir [Department of Chemistry, Islamic Azad University, Savadkooh Branch, Savadkooh (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); Veismohammadi, Bahareh [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Faridbod, Farnoush [Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Abkenar, Shiva Dehghan [Department of Chemistry, Islamic Azad University, Savadkooh Branch, Savadkooh (Iran, Islamic Republic of); Norouzi, Parviz [Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of)

2010-04-07

For the first time a highly sensitive and selective fluorimetric optode membrane was prepared for determination of trace amounts of Tb(III) ions in phosphate rock samples. The Tb(III) sensing system was constructed by incorporating 5-(dimethylamino)-N'-(2-hydroxy-1-naphthoyl) naphthalene-1-sulfonohydrazine (L) as a neutral Tb(III)-selective fluoroionophore, in the plasticized PVC membrane containing sodium tetraphenyl borate as a liphophilic anionic additive. The response of the optode is based on the strong fluorescence quenching of L by Tb{sup 3+} ions. At a pH value of 5.0, the optode displays a wide concentration range of 1.0 x 10{sup -7} to 1.0 x 10{sup -2} M, with a relatively fast response time of less than 45 s. In addition, to high stability and reproducibility, the sensor shows a unique selectivity towards Tb{sup 3+} ion with respect to common cations. The optode was applied successfully to the trace determination of terbium ion in binary mixture and water samples and the determination of Tb{sup 3+} in phosphate rock samples.

An SH2 domain-based tyrosine kinase assay using biotin ligase modified with a terbium(III) complex.

Science.gov (United States)

Sueda, Shinji; Shinboku, Yuki; Kusaba, Takeshi

2013-01-01

Src homology 2 (SH2) domains are modules of approximately 100 amino acids and are known to bind phosphotyrosine-containing sequences with high affinity and specificity. In the present work, we developed an SH2 domain-based assay for Src tyrosine kinase using a unique biotinylation reaction from archaeon Sulfolobus tokodaii. S. tokodaii biotinylation has a unique property that biotin protein ligase (BPL) forms a stable complex with its biotinylated substrate protein (BCCP). Here, an SH2 domain from lymphocyte-specific tyrosine kinase was genetically fused to a truncated BCCP, and the resulting fusion protein was labeled through biotinylation with BPL carrying multiple copies of a luminescent Tb(3+) complex. The labeled SH2 fusion proteins were employed to detect a phosphorylated peptide immobilized on the surface of the microtiter plate, where the phosphorylated peptide was produced by phosphorylation to the substrate peptide by Src tyrosine kinase. Our assay allows for a reliable determination of the activity of Src kinase lower than 10 pg/μL by a simple procedure.

Synthesis, structural, thermal and optical studies of rare earth coordinated complex: Tb(Sal){sub 3}Phen

Energy Technology Data Exchange (ETDEWEB)

Kaur, Gagandeep; Dwivedi, Y. [Laser and Spectroscopy Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221005 (India); Rai, S.B., E-mail: sbrai49@yahoo.co.in [Laser and Spectroscopy Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221005 (India)

2011-11-01

Highlights: {yields} RE coordinated complex of Tb(Sal){sub 3}Phen in crystalline phases were synthesized. {yields} Enhancement in luminescence of Tb{sup 3+} was observed in complex on 355 nm excitation. {yields} Fluorescence enhancement is due to the efficient energy transfer from Sal to Tb{sup 3+}. {yields} An observed increase in lifetime of Tb{sup 3+} is due to encapsulation in Sal/Phen network. {yields} The present system is a deserving candidate for LSC when coupled with solar cells. - Abstract: Complexes of salicylic acid (Sal) and 1,10-phenanthroline (Phen) were synthesized coordinated with terbium ion (Tb{sup 3+}) in crystalline phases. The structural characterizations of the lanthanide complex were made using FT-IR, NMR ({sup 1}H and {sup 13}C) and XRD techniques. These measurements confirm the formation of Tb(Sal){sub 3}Phen complex structure. The thermal aspects of the complex were examined using DTA and TGA techniques. An enhancement in luminescence intensity of Tb{sup 3+} ion bands were observed in Tb(Sal){sub 3}Phen complex as compared to TbCl{sub 3} crystals on 355 nm laser excitation. Enhancement is reported due to the efficient energy transfer process from Sal to Tb{sup 3+} ions. This is also confirmed by the time resolved photoluminescence spectroscopy with increase in lifetime of Tb{sup 3+} ions due to encapsulation in Sal/Phen network. Our system in itself can be a deserving candidate for luminescent solar collector material when coupled with solar cells.

Determination of terbium in phosphate rock by Tb3+-selective fluorimetric optode based on dansyl derivative as a neutral fluorogenic ionophore.

Science.gov (United States)

Hosseini, Morteza; Ganjali, Mohammad Reza; Veismohammadi, Bahareh; Faridbod, Farnoush; Abkenar, Shiva Dehghan; Norouzi, Parviz

2010-04-07

For the first time a highly sensitive and selective fluorimetric optode membrane was prepared for determination of trace amounts of Tb(III) ions in phosphate rock samples. The Tb(III) sensing system was constructed by incorporating 5-(dimethylamino)-N'-(2-hydroxy-1-naphthoyl) naphthalene-1-sulfonohydrazine (L) as a neutral Tb(III)-selective fluoroionophore, in the plasticized PVC membrane containing sodium tetraphenyl borate as a liphophilic anionic additive. The response of the optode is based on the strong fluorescence quenching of L by Tb(3+) ions. At a pH value of 5.0, the optode displays a wide concentration range of 1.0 x 10(-7) to 1.0 x 10(-2)M, with a relatively fast response time of less than 45 s. In addition, to high stability and reproducibility, the sensor shows a unique selectivity towards Tb(3+) ion with respect to common cations. The optode was applied successfully to the trace determination of terbium ion in binary mixture and water samples and the determination of Tb(3+) in phosphate rock samples. Crown Copyright 2010. Published by Elsevier B.V. All rights reserved.

Construction of Polynuclear Lanthanide (Ln = Dy(III), Tb(III), and Nd(III)) Cage Complexes Using Pyridine-Pyrazole-Based Ligands: Versatile Molecular Topologies and SMM Behavior.

Science.gov (United States)

Bala, Sukhen; Sen Bishwas, Mousumi; Pramanik, Bhaskar; Khanra, Sumit; Fromm, Katharina M; Poddar, Pankaj; Mondal, Raju

2015-09-08

Employment of two different pyridyl-pyrazolyl-based ligands afforded three octanuclear lanthanide(III) (Ln = Dy, Tb) cage compounds and one hexanuclear neodymium(III) coordination cage, exhibiting versatile molecular architectures including a butterfly core. Relatively less common semirigid pyridyl-pyrazolyl-based asymmetric ligand systems show an interesting trend of forming polynuclear lanthanide cage complexes with different coordination environments around the metal centers. It is noteworthy here that construction of lanthanide complex itself is a challenging task in a ligand system as soft N-donor rich as pyridyl-pyrazol. We report herein some lanthanide complexes using ligand containing only one or two O-donors compare to five N-coordinating sites. The resultant multinuclear lanthanide complexes show interesting magnetic and spectroscopic features originating from different spatial arrangements of the metal ions. Alternating current (ac) susceptibility measurements of the two dysprosium complexes display frequency- and temperature-dependent out-of-phase signals in zero and 0.5 T direct current field, a typical characteristic feature of single-molecule magnet (SMM) behavior, indicating different energy reversal barriers due to different molecular topologies. Another aspect of this work is the occurrence of the not-so-common SMM behavior of the terbium complex, further confirmed by ac susceptibility measurement.

High fluorescence emission of carboxylic acid functionalized polystyrene/BaTiO{sub 3} nanocomposites and rare earth metal complexes: Preparation and characterization

Energy Technology Data Exchange (ETDEWEB)

Cao, X. T.; Showkat, A. M.; Wang, Z.; Lim, K. T., E-mail: ktlim@pknu.ac.kr [Department of Imaging System Engineering, Pukyong National University, Busan 608-737 (Korea, Republic of)

2015-03-30

Noble fluorescence nanocomposite compound based on barium titanate nanoparticles (BTO), polystyrene (PSt), and terbium ion (Tb{sup 3+}) was synthesized by a combination of surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization, Friedel-Crafts alkylation reaction and coordinate chemistry. Initially, a modification of surface of BTO was conducted by an exchange process with S-benzyl S’-trimethoxysilylpropyltrithiocarbonate to create macro-initiator for polymerization of styrene. Subsequently, aryl carboxylic acid functionalized polystyrene grafted barium titanate (BTO-g-PSt-COOH) was generated by substitution reaction between 4-(Chloromethyl) benzoic acid and PSt chains. The coordination of the nanohybrids with Tb{sup 3+} ions afforded fluorescent Tb{sup 3+} tagged aryl carboxylic acid functionalized polystyrene grafted barium titanate (BTO-g-PSt-Tb{sup 3+}) complexes. Structure, morphology, and fluorescence properties of nanohybrid complexes were investigated by respective physical and spectral studies. FT-IR and SEM analyses confirmed the formation of BTO-g-PSt-Tb{sup 3+}nanohybrids. Furthermore, TGA profiles demonstrated the grafting of aryl carboxylic acid functionalized polystyrene on BTO surface. Optical properties of BTO-g-PSt-Tb{sup 3+} complexes were investigated by fluorescence spectroscopy.

Study of quantum dot based on tin/yttrium mixed oxide doped with terbium to be used as biomarker

International Nuclear Information System (INIS)

Paganini, Paula P.; Felinto, Maria Claudia F.C.; Kodaira, Claudia A.; Brito, Hermi F.; Nunes, Luiz Antonio O.

2009-01-01

Quantum dots (semiconductors nanocrystals) have brought a promising field to develop a new generation of luminescent biomarkers. The use of lanthanides ions as luminescent markers has many advantages, for example a security method, low cost, high specificity and also the luminescence can be promptly measured with high sensibility and accuracy. These luminescent dots are functionalized with biomolecules. For the luminophore particle to be connect with biologicals molecules (for example covalent antibody) is necessary a previous chemical treatment to modify luminophore particle surface and this process is called functionalization. A prior chemical treatment with changes on the surface luminophore particle is necessary to couple the luminophore to biological molecules. This process can be used as coating which can protect these particles from being dissolved by acid as well as provide functional groups for biological conjugation. This work presents a photoluminescence study of nanoparticles based on tin/yttrium mixed oxides doped with terbium (SnO 2 /Y 2 O 3 :Tb 3+ ), synthesized by coprecipitation method. The nanoparticles were submitted to thermal treatment and characterized by X-Ray Powder Diffraction (XRD) that showed cassiterite phase formation and the influence of thermal treatment on nanoparticles structures. These nanoparticles going to be functionalized with a natural polysaccharide (chitosan) in order to form microspheres. These microspheres going to be irradiated with gamma radiation to sterilization and it can be evaluated if the nanoparticles are resistant to irradiation and they do not lose functionality with this process. (author)

Preparation of a novel fluorescence probe of terbium-europium co-luminescence composite nanoparticles and its application in the determination of proteins

Energy Technology Data Exchange (ETDEWEB)

Gao Feng [College of Chemistry and Materials Science, Anhui Key Laboratory of Chemo/Biosensing, Anhui Normal University, Wuhu 241000 (China)], E-mail: summit8848cn@hotmail.com; Luo Fabao; Tang Lijuan; Dai Lu [College of Chemistry and Materials Science, Anhui Key Laboratory of Chemo/Biosensing, Anhui Normal University, Wuhu 241000 (China); Wang Lun [College of Chemistry and Materials Science, Anhui Key Laboratory of Chemo/Biosensing, Anhui Normal University, Wuhu 241000 (China)], E-mail: wanglun@mail.ahnu.edu.cn

2008-03-15

Terbium-europium Tb-Eu/acetylacetone(acac)/poly(acrylamide) (PAM) co-luminescence composite nanoparticles were successfully prepared using the ultrasonic approach. The as-prepared composite nanoparticles show the characteristic emission spectra of Tb{sup 3+}, located at 496 and 549 nm. Furthermore, the nanoparticles are water soluble, stable and have extremely narrow emission bands and high internal fluorescence quantum yield due to the co-luminescence effect. Further studies indicate that proteins can interact with the nanoparticles and induce the fluorescence quenching of the nanoparticles. Based on the fluorescence quenching of nanopaticles in the presence of proteins, a novel method for the sensitive determination of trace amounts of proteins was proposed. Under the optimal experimental conditions, the linear ranges of calibration curves are 0-3.5 {mu}g mL{sup -1} for human serum albumin (HSA) and 0-4.0 {mu}g mL{sup -1} for {gamma}-globulin ({gamma}-IgG), respectively. The limits of detection are 7.1 for HSA and 6.7ng mL{sup -1} for {gamma}-IgG, respectively. The method was applied to the quantification of proteins in synthetic samples and actual human serum samples with satisfactory results. This proposed method is sensitive, simple and has potential application in the clinical assay of proteins.

Chiral recognition of proteins having L-histidine residues on the surface with lanthanide ion complex incorporated-molecularly imprinted fluorescent nanoparticles.

Science.gov (United States)

Uzun, Lokman; Uzek, Recep; Senel, Serap; Say, Ridvan; Denizli, Adil

2013-08-01

In this study, lanthanide ion complex incorporated molecularly imprinted fluorescent nanoparticles were synthesized. A combination of three novel approaches was applied for the purpose. First, lanthanide ions [Terbium(III)] were complexed with N-methacryloyl-L-histidine (MAH), polymerizable derivative of L-histidine amino acid, in order to incorporate the complex directly into the polymeric backbone. At the second stage, L-histidine molecules imprinted nanoparticles were utilized instead of whole protein imprinting in order to avoid whole drawbacks such as fragility, complexity, denaturation tendency, and conformation dependency. At the third stage following the first two steps mentioned above, imprinted L-histidine was coordinated with cupric ions [Cu(II)] to conduct the study under mild conditions. Then, molecularly imprinted fluorescent nanoparticles synthesized were used for L-histidine adsorption from aqueous solution to optimize conditions for adsorption and fluorimetric detection. Finally, usability of nanoparticles was investigated for chiral biorecognition using stereoisomer, D-histidine, racemic mixture, D,L-histidine, proteins with surface L-histidine residue, lysozyme, cytochrome C, or without ribonuclease A. The results revealed that the proposed polymerization strategy could make significant contribution to the solution of chronic problems of fluorescent component introduction into polymers. Additionally, the fluorescent nanoparticles reported here could be used for selective separation and fluorescent monitoring purposes. Copyright © 2013 Elsevier B.V. All rights reserved.

Study of the role of complete fusion in the reaction of 48Ca and 56Fe with cerium and terbium

International Nuclear Information System (INIS)

Morrissey, D.J.

1978-05-01

48 Ca and 56 Fe beams from the Super HILAC accelerator were used to irradiate thick metal foils of cerium and terbium. Product gamma ray activities were detected offline and individual products were identified by half-life, gamma ray energy and gamma ray abundances. The production cross sections were iteratively fit to charge and mass dispersions to allow correction for parent decay and calculation of mass yields. From the mass yield curves contributions from quasielastic transfer, deep inelastic transfer and complete fusion reaction mechanisms were interred. Complete fusion was made up on contributions from both evaporation residue and fusion-fission products for the 48 Ca induced reactions. However, only fusion-fission products were detected in the 56 Fe induced reactions. Critical angular momenta for fusion were found to be 82 +- 8 h for 48 Ca + 159 Tb and 34 +- 5 h for 56 Fe + 140 Ce, which can be compared with 53 +- 8 h for 12 C + 197 Au (Natowitz, 1970) and 86 +- 5 h for 40 Ar + 165 Ho (Hanappe, 1973). All of these reactions lead to essentially the same compound nucleus and seem to show the dramatic decline in complete fusion for heavy ions larger than 40 Ar. The prediction of this decline was found to be beyond the model calculations of Bass and the critical distance approach of Glas and Mosel

Chiral recognition of proteins having L-histidine residues on the surface with lanthanide ion complex incorporated-molecularly imprinted fluorescent nanoparticles

International Nuclear Information System (INIS)

Uzun, Lokman; Uzek, Recep; Şenel, Serap; Say, Ridvan; Denizli, Adil

2013-01-01

In this study, lanthanide ion complex incorporated molecularly imprinted fluorescent nanoparticles were synthesized. A combination of three novel approaches was applied for the purpose. First, lanthanide ions [Terbium(III)] were complexed with N-methacryloyl-L-histidine (MAH), polymerizable derivative of L-histidine amino acid, in order to incorporate the complex directly into the polymeric backbone. At the second stage, L-histidine molecules imprinted nanoparticles were utilized instead of whole protein imprinting in order to avoid whole drawbacks such as fragility, complexity, denaturation tendency, and conformation dependency. At the third stage following the first two steps mentioned above, imprinted L-histidine was coordinated with cupric ions [Cu(II)] to conduct the study under mild conditions. Then, molecularly imprinted fluorescent nanoparticles synthesized were used for L-histidine adsorption from aqueous solution to optimize conditions for adsorption and fluorimetric detection. Finally, usability of nanoparticles was investigated for chiral biorecognition using stereoisomer, D-histidine, racemic mixture, D,L-histidine, proteins with surface L-histidine residue, lysozyme, cytochrome C, or without ribonuclease A. The results revealed that the proposed polymerization strategy could make significant contribution to the solution of chronic problems of fluorescent component introduction into polymers. Additionally, the fluorescent nanoparticles reported here could be used for selective separation and fluorescent monitoring purposes. Highlights: • Lanthanide ion complex incorporated molecularly imprinted fluorescent nanoparticles • Direct incorporation of the fluorescent complex into polymeric backbone. • Imprinting by assistance of cupric ion coordination into nanoparticles • Evaluation of the chiral biorecognition ability of nanoparticles • Simultaneous selective separation and fluorescent monitoring

Chiral recognition of proteins having L-histidine residues on the surface with lanthanide ion complex incorporated-molecularly imprinted fluorescent nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Uzun, Lokman, E-mail: lokman@hacettepe.edu.tr [Hacettepe University, Department of Chemistry, 06381, Ankara (Turkey); Uzek, Recep; Şenel, Serap [Hacettepe University, Department of Chemistry, 06381, Ankara (Turkey); Say, Ridvan [Anadolu University, Department of Chemistry, 26470, Eskisehir (Turkey); Denizli, Adil [Hacettepe University, Department of Chemistry, 06381, Ankara (Turkey)

2013-08-01

In this study, lanthanide ion complex incorporated molecularly imprinted fluorescent nanoparticles were synthesized. A combination of three novel approaches was applied for the purpose. First, lanthanide ions [Terbium(III)] were complexed with N-methacryloyl-L-histidine (MAH), polymerizable derivative of L-histidine amino acid, in order to incorporate the complex directly into the polymeric backbone. At the second stage, L-histidine molecules imprinted nanoparticles were utilized instead of whole protein imprinting in order to avoid whole drawbacks such as fragility, complexity, denaturation tendency, and conformation dependency. At the third stage following the first two steps mentioned above, imprinted L-histidine was coordinated with cupric ions [Cu(II)] to conduct the study under mild conditions. Then, molecularly imprinted fluorescent nanoparticles synthesized were used for L-histidine adsorption from aqueous solution to optimize conditions for adsorption and fluorimetric detection. Finally, usability of nanoparticles was investigated for chiral biorecognition using stereoisomer, D-histidine, racemic mixture, D,L-histidine, proteins with surface L-histidine residue, lysozyme, cytochrome C, or without ribonuclease A. The results revealed that the proposed polymerization strategy could make significant contribution to the solution of chronic problems of fluorescent component introduction into polymers. Additionally, the fluorescent nanoparticles reported here could be used for selective separation and fluorescent monitoring purposes. Highlights: • Lanthanide ion complex incorporated molecularly imprinted fluorescent nanoparticles • Direct incorporation of the fluorescent complex into polymeric backbone. • Imprinting by assistance of cupric ion coordination into nanoparticles • Evaluation of the chiral biorecognition ability of nanoparticles • Simultaneous selective separation and fluorescent monitoring.

The purification of the rare earth metals. II

International Nuclear Information System (INIS)

Jordan, R.G.; Jones, D.W.; Hems, V.J.

1975-01-01

Solid-state electrotransport processing has been demonstrated as a technique for purifying terbium. The results show that both oxygen and nitrogen migrate rapidly in the same direction as the electron flow. Although hydrogen contamination occurs on contact with air, terbium of better than 99.9 at. % has been prepared from commercially available starting material. The preparation and characterisation of high-quality single-crystal terbium specimens is also described. (Auth.)

Binding of chlorfenvinphos and malathion with DNA and their detection using new sensitive luminescent Tb(III) complex probe

Energy Technology Data Exchange (ETDEWEB)

Azab, Hassan A. [Chemistry Department, Faculty of Science, Suez Canal University, 41522 Ismailia (Egypt); Kamel, Rasha M., E-mail: rashamoka@yahoo.com [Chemistry Department, Faculty of Science, Suez University, 43518 Suez (Egypt)

2016-02-15

In this work, the interaction of new luminescent terbium-N(acetoacetyl)-3-allyl-2hydroxybenzaldehyde hydrazone complex in a metal ligand ratio 1:2 in ethanol was studied with different pesticides, using fluorescence technique. The results indicate that the pesticides chlorfenvinphos and malathion exhibit quenching effect on the characteristics emission peak for Tb(III) at λ=545 nm. The luminescence variations values using the probe Tb(III)(HBH){sub 2} fit Stern–Volmer equation, where the detection limits are 4.53 and 9.59 µmol/L for chlorfenvinphos and malathion, respectively. The thermodynamic parameters associated with the interaction of the complex with the two pesticides were calculated, where the reaction is spontaneous through the obtained negative values of free energy change ΔG, and the process is of exothermic nature with decrease in entropy. Hence the nature of forces acting between the complex and pesticide molecules are Vander Val's and hydrogen bond. Also, it was found that the quenching mechanism is static type. Effect of some relevant interferents on the detection of pesticides has been investigated. The new sensing complex was applied to the determination of the pesticides in different real water samples (tap, river, and waste water) with precise recovery. Also, the effect of different concentrations of pesticides on the fluorescence spectrum of DNA was studied. - Highlights: • The method can be used for detection of pesticides in environmental samples. • The DL is 4.53 and 9.59 µmol L{sup −1} for chlorfenvinphos and malathion respectively. • Stern–Volmer studies at different temperatures were studied. • Effect of some interferents on the detection of pesticides has been investigated.

Coordination chemistry of several radius-sensitive complexones and applications to lanthanide-actinide separations

Energy Technology Data Exchange (ETDEWEB)

Potter, M.W.

1981-10-01

The relationships between the lanthanide complex formation equilibria and the lanthanide-actinide separation application of three radius sensitive ligands have been studied. The consecutive stepwise formation constants of the 1:1, 2:1, and 3:1 chelate species formed by the interaction of DHDMB and the tripositive lanthanides and yttrium were determined potentiometrically at 0.1 M ionic strength and 25/sup 0/C. Results indicate that three different coordination modes, one tridentate and two bidentate are in evidence. Tracer level /sup 241/Am - /sup 155/Eu cation-exchange experiments utilizing DHDMB eluents indicate that this dihydroxycarboxylate does not form a sufficiently strong americium complex to elute that actinide ahead of europium. The overall stability of the americium 3:1 complex appears intermediate between samarium and europium. Cation-exchange elutions of /sup 241/Am, /sup 155/Eu, and /sup 160/Tb mixtures with EEDTA solutions prove that the EEDTA ligand is capable of eluting americium ahead of all of the tripositive lanthanide cations. The minimum separation occurs with terbium, where the Am-Tb separation factor is 1.71. 1,5-diaminopentane-N,N,N',N'-tetraacetic acid (PMDTA) was synthesized using cation exchange. A mathematical method was developed for the formation constants of the protonated and unprotonated lanthanide-PMDTA complexes from potentiometry. Cation-exchange elutions of tracer quantities of Am, Eu, and Tb revealed that terbium is eluted ahead of both americium and europium.

Physico-chemical characterization of terbium-161-chloride (161TbCl3) radioisotope from irradiated natural gadolinium oxide target

International Nuclear Information System (INIS)

Azmairit Aziz; Nana Suherman

2015-01-01

Currently cancer patients are increasing every year in Indonesia and become the third leading cause of death after heart disease and high blood pressure. Terbium-161 ( 161 Tb) is a low β- emitter (E β - = 0.155 MeV, T 1/2 = 6.9 d) and very similar to 177 Lu in terms of half-life, E β - energy and chemical properties.However, 161 Tb also ejects internal conversion electrons and Auger electrons which can provide a greater therapeutic effect than 177 Lu. Radioisotope of 161 Tb can be produced as a carrier-free for use in labeling of biomolecules as a targeted radiopharmaceutical for cancer therapy. 161 Tb was obtained through 160 Gd(n,γ) 161 Tb nuclear reaction by thermal neutron bombardment on 100 mg of natural gadolinium oxide target in RSG-G.A. Siwabessy at a thermal neutron flux of ~10 14 n.cm -2 .s -1 and followed by radiochemical separation of 161 Tb from Gd isotopes using extraction chromatography method. The physico-chemical characterization of 161 TbCl 3 solution was studied by determination of its radionuclide purity by means of a γ-rays spectrometry with HP-Ge detector coupled to a multichannel analyzer (MCA). Radiochemical purity was determined using paper chromatography and paper electrophoresis methods. The results showed that 161 TbCl 3 radioisotope has a pH of 2, radiochemical purity of 99.64 ± 0.34%, radionuclide purity of 99.69 ± 0.20%, specific activity and radioactive concentration at the end of irradiation (EOI) of 2.26 – 5.31 Ci/mg and 3.84 – 9.03 mCi/mL, respectively. 161 TbCl 3 solution stable for 3 weeks at room temperature with a radiochemical purity of 98.41 ± 0.42%. 161 TbCl 3 solution from irradiated natural gadolinium oxide target has the physico-chemical characteristic that meets the requirements for use as a precursor in preparation of radiopharmaceuticals. (author)

A Broad G Protein-Coupled Receptor Internalization Assay that Combines SNAP-Tag Labeling, Diffusion-Enhanced Resonance Energy Transfer, and a Highly Emissive Terbium Cryptate.

Science.gov (United States)

Levoye, Angélique; Zwier, Jurriaan M; Jaracz-Ros, Agnieszka; Klipfel, Laurence; Cottet, Martin; Maurel, Damien; Bdioui, Sara; Balabanian, Karl; Prézeau, Laurent; Trinquet, Eric; Durroux, Thierry; Bachelerie, Françoise

2015-01-01

Although G protein-coupled receptor (GPCR) internalization has long been considered as a major aspect of the desensitization process that tunes ligand responsiveness, internalization is also involved in receptor resensitization and signaling, as well as the ligand scavenging function of some atypical receptors. Internalization thus contributes to the diversity of GPCR-dependent signaling, and its dynamics and quantification in living cells has generated considerable interest. We developed a robust and sensitive assay to follow and quantify ligand-induced and constitutive-induced GPCR internalization but also receptor recycling in living cells. This assay is based on diffusion-enhanced resonance energy transfer (DERET) between cell surface GPCRs labeled with a luminescent terbium cryptate donor and a fluorescein acceptor present in the culture medium. GPCR internalization results in a quantifiable reduction of energy transfer. This method yields a high signal-to-noise ratio due to time-resolved measurements. For various GPCRs belonging to different classes, we demonstrated that constitutive and ligand-induced internalization could be monitored as a function of time and ligand concentration, thus allowing accurate quantitative determination of kinetics of receptor internalization but also half-maximal effective or inhibitory concentrations of compounds. In addition to its selectivity and sensitivity, we provided evidence that DERET-based internalization assay is particularly suitable for characterizing biased ligands. Furthermore, the determination of a Z'-factor value of 0.45 indicates the quality and suitability of DERET-based internalization assay for high-throughput screening (HTS) of compounds that may modulate GPCRs internalization.

Therapeutic use of radioactive isotopes

CERN Document Server

Caroline Duc

2013-01-01

In December, researchers from ISOLDE-CERN, the Paul Scherrer Institute (PSI) and the Institut Laue-Langevin (ILL) published the results of an in vivo study which successfully proved the effectiveness of four terbium isotopes for diagnosing and treating cancerous tumours.   Four terbium isotopes suitable for clinical purposes. “ISOLDE is the only installation capable of supplying terbium isotopes of such purity and intensity in the case of three out of the four types used in this study,” explains Karl Johnson, a physicist at ISOLDE.  “Producing over a thousand different isotopes, our equipment offers the widest choice of isotopes in the world!” Initially intended for fundamental physics research, ISOLDE has diversified its activities over time to invest in various projects in the materials science, biochemistry and nuclear medicine fields. The proof-of-concept study has confirmed that the four terbium isotopes 149Tb, 152Tb, 155Tb produ...

Voltammetric determination of zirconium using azo compounds

International Nuclear Information System (INIS)

Orshulyak, O.O.; Levitskaya, G.D.

2008-01-01

The optimum conditions for zirconium complexation with azo compounds are found. The applicability of Eriochrome Red B, Calcon, and Calcion to the voltammetric determination of zirconium, total Zr(IV) and Hf(IV), and Zr(IV) in the presence of Zn(II), Cu(II), Cd(II), Ni(II), or Ti(IV) is demonstrated. The developed procedures are used to determine zirconium in a terbium alloy and in an alloy for airplane wheel drums [ru

Fluorescence enhancement of samarium complex co-doped with terbium complex in a poly(methyl methacrylate) matrix

International Nuclear Information System (INIS)

Jiu Hongfang; Zhang Lixin; Liu Guode; Fan Tao

2009-01-01

The fluorescence property of Sm(DBM) 3 phen- (DBM-dibenzoylmethide, phen-1,10-phenanthroline) and Tb(DBM) 3 phen-co-doped poly(methyl methacrylate) (PMMA) was investigated. The excitation, emission spectra and fluorescence lifetime of the co-doped samples were examined. In the co-doped samples, the luminescence intensities of Sm 3+ enhance with an increase of the Tb(DBM) 3 phen content and with a decrease of the Sm(DBM) 3 phen content. The reason for the fluorescence enhancement effect in the co-doped polymer is the intermolecular energy transfer. To give a vivid picture for this co-doped system, a model for the fluorescence enhancement of Sm(DBM) 3 phen- and Tb(DBM) 3 phen-co-doped PMMA is presented

A broad G protein-coupled receptor internalization assay that combines SNAP-tag labeling, diffusion-enhanced resonance energy transfer, and a highly emissive terbium cryptate acceptor

Directory of Open Access Journals (Sweden)

Angélique eLEVOYE

2015-11-01

Full Text Available Although G protein-coupled receptor (GPCR internalization has long been considered a major aspect of the desensitization process that tunes ligand responsiveness, internalization is also involved in receptor resensitization and signaling, as well as the ligand scavenging function of some atypical receptors. Internalization thus contributes to the diversity of GPCR-dependent signaling, and its dynamics and quantification in living cells has generated considerable interest. We developed a robust and sensitive assay to follow and quantify ligand-induced and constitutive GPCR internalization but also receptor recycling in living cells. This assay is based on diffusion-enhanced resonance energy transfer (DERET between cell surface GPCRs labeled with a luminescent terbium cryptate donor and a fluorescein acceptor present in the culture medium. GPCR internalization results in a quantifiable reduction of energy transfer. This method yields a high signal-to-noise ratio due to time-resolved measurements. For various GPCRs belonging to different classes, we demonstrated that constitutive and ligand-induced internalization could be monitored as a function of time and ligand concentration, thus allowing accurate quantitative determination of kinetics of receptor internalization but also half-maximal effective or inhibitory concentrations of compounds. In addition to its selectivity and sensitivity, we provided evidence that DERET-based internalization assay is particularly suitable for characterizing biased ligands. Furthermore, the determination of a Z’-factor value of 0.45 indicates the quality and suitability of DERET-based internalization assay for high-throughput screening (HTS of compounds that may modulate GPCRs internalization.

Study of the role of complete fusion in the reaction of /sup 48/Ca and /sup 56/Fe with cerium and terbium. [Cross sections, yield curves, tables

Energy Technology Data Exchange (ETDEWEB)

Morrissey, D.J.

1978-05-01

/sup 48/Ca and /sup 56/Fe beams from the Super HILAC accelerator were used to irradiate thick metal foils of cerium and terbium. Product gamma ray activities were detected offline and individual products were identified by half-life, gamma ray energy and gamma ray abundances. The production cross sections were iteratively fit to charge and mass dispersions to allow correction for parent decay and calculation of mass yields. From the mass yield curves contributions from quasielastic transfer, deep inelastic transfer and complete fusion reaction mechanisms were interred. Complete fusion was made up on contributions from both evaporation residue and fusion-fission products for the /sup 48/Ca induced reactions. However, only fusion-fission products were detected in the /sup 56/Fe induced reactions. Critical angular momenta for fusion were found to be 82 +- 8 h for /sup 48/Ca + /sup 159/Tb and 34 +- 5 h for /sup 56/Fe + /sup 140/Ce, which can be compared with 53 +- 8 h for /sup 12/C + /sup 197/Au (Natowitz, 1970) and 86 +- 5 h for /sup 40/Ar + /sup 165/Ho (Hanappe, 1973). All of these reactions lead to essentially the same compound nucleus and seem to show the dramatic decline in complete fusion for heavy ions larger than /sup 40/Ar. The prediction of this decline was found to be beyond the model calculations of Bass and the critical distance approach of Glas and Mosel.

Stability constants and thermodynamic parameters of trivalent gadolinium, yttrium, terbium, dysprosium and holmium complexes with 2-(p-sulphophenylazo) 1,8-dihydroxynaphthalene 3,6 disulphonic acid (trisodium salt)[SPADNS

International Nuclear Information System (INIS)

Dubey, S.N.; Nagpal, S.; Kalra, H.L.; Puri, D.M.

1980-01-01

The stepwise stability constants of Gd(III), Y(III), Tb(III), Dy(III) and Ho(III) complexes with SPADNS have been determined potentiometrically in aqueous solution using Bjerrum-Calvin technique as modified by Irving and Rossotti at different temperatures (20deg and 40deg) and 0.1 M ionic strength (NaClO 4 ). The trend in the stability of these metal complexes has been found to be: Ho(III) > Dy(III) > Tb(III) > Y(III) > Gd(III). The overall changes in ΔGdeg, ΔHdeg and ΔSdeg accompanying the complex formation have also been determined. (author)

Stability constants and thermodynamic parameters of trivalent gadolinium, yttrium, terbium, dysprosium and holmium complexes with 2-(p-sulphophenylazo) 1,8-dihydroxynaphthalene 3,6 disulphonic acid (trisodium salt)(SPADNS)

Energy Technology Data Exchange (ETDEWEB)

Dubey, S.N.; Nagpal, S.; Kalra, H.L.; Puri, D.M. (Kurukshetra Univ. (India). Dept. of Chemistry)

1980-10-01

The stepwise stability constants of Gd(III), Y(III), Tb(III), Dy(III) and Ho(III) complexes with SPADNS have been determined potentiometrically in aqueous solution using Bjerrum-Calvin technique as modified by Irving and Rossotti at different temperatures (20deg and 40deg) and 0.1 M ionic strength (NaClO/sub 4/). The trend in the stability of these metal complexes has been found to be: Ho(III) > Dy(III) > Tb(III) > Y(III) > Gd(III). The overall changes in ..delta..Gdeg, ..delta..Hdeg and ..delta..Sdeg accompanying the complex formation have also been determined.

The influence of carboxilate, phosphinate and seleninate groups on luminescent properties of lanthanides complexes

International Nuclear Information System (INIS)

Monteiro, Jorge H.S.K.; Formiga, André L.B.; Sigoli, Fernando A.

2014-01-01

sufficient to significantly modify the population of the europium(III) 5 D 0,1 levels and therefore the emission quantum yield. - Highlights: • Influences of ligands on luminescence of europium(III) and terbium(III) complexes. • Ligands: benzoic acid, phenylseleninic acid, and phenylphosphinic acid. • Ground state geometries were obtained from semi-empirical methods. • Theoretical values of JO parameters are compared to experimental ones. • Nature of chemical bonds, energy transfer rates and emission quantum yields

Tumor specific lung cancer diagnostics with multiplexed FRET immunoassays

Science.gov (United States)

Geißler, D.; Hill, D.; Löhmannsröben, H.-G.; Thomas, E.; Lavigne, A.; Darbouret, B.; Bois, E.; Charbonnière, L. J.; Ziessel, R. F.; Hildebrandt, N.

2010-02-01

An optical multiplexed homogeneous (liquid phase) immunoassay based on FRET from a terbium complex to eight different fluorescent dyes is presented. We achieved highly sensitive parallel detection of four different lung cancer specific tumor markers (CEA, NSE, SCC and CYFRA21-1) within a single assay and show a proof-of-principle for 5- fold multiplexing. The method is well suited for fast and low-cost miniaturized point-of-care testing as well as for highthroughput screening in a broad range of in-vitro diagnostic applications.

Design, synthesis and evaluation of carbamoyl-methyl-phosphine sulfide (CMPS)-based chelates for separation of lanthanides and actinides

Energy Technology Data Exchange (ETDEWEB)

Matlokaa, K.; Saha, A.K.; Srinivasan, P.; Scott, M.J. [Florida Univ., Dept. of Chemistry, FL (United States)

2007-10-15

C{sub 3}-symmetric tri-phenoxy-methane platforms were substituted with carbamoyl-methyl-phosphine sulfide arms and these tris-CMPS compounds were evaluated as extractants for f-element metal ions from 1 M nitric acid solution. Their properties were compared to the carbamoyl-methyl-phosphine oxide derivatives on the same tri-phenoxy-methane platform (tris-CMPO). The terbium complex of tris-CMPS was crystallized and examined via X-ray structural analysis to provide valuable insight into the binding properties of the soft tripodal chelate. (authors)

Electrochemiluminescence properties of Tb(III) nicotinic acid complex and its analytical application

Energy Technology Data Exchange (ETDEWEB)

Yang, Yu [College of Chemistry and Material Science, Anhui Normal University, No. 1 Beijing East Road, Wuhu 241000 (China); Zhang, Yuqin [The Department of Material Engineering, Wuhu Institute of Technology, No. 201 Wenjin Road, Wuhu 241003 (China); Shu, Guibo; Dong, Qin; Zou, Lili [College of Chemistry and Material Science, Anhui Normal University, No. 1 Beijing East Road, Wuhu 241000 (China); Zhu, Yinggui, E-mail: ygzhu08@mail.ahnu.edu.cn [College of Chemistry and Material Science, Anhui Normal University, No. 1 Beijing East Road, Wuhu 241000 (China)

2015-03-15

A water soluble lanthanide Tb(III) complex Tb{sub 2}(C{sub 6}NO{sub 2}H{sub 4}){sub 6}(H{sub 2}O){sub 4} has been synthesized as luminescent material, and it is characterized by X-ray crystallography, infrared spectra and elemental analysis, respectively. This material showed excellent characterize of electrochemiluminescence (ECL) in the presence of co-reactant potassium peroxodisulfate (K{sub 2}S{sub 2}O{sub 8}) at glassy carbon electrode. With the increase of the concentration for nicotinic acid (NA), the ECL intensity of the complex/K{sub 2}S{sub 2}O{sub 8} system in HAc–NaAc buffer solution will be decreased apparently. Novel approach for the detection of nicotinic acid (NA) was developed based on the quenching effect of NA. Furthermore, the possible mechanisms for the ECL behavior of Tb{sub 2}(C{sub 6}NO{sub 2}H{sub 4}){sub 6}(H{sub 2}O){sub 4}/K{sub 2}S{sub 2}O{sub 8} system are proposed. The effects of K{sub 2}S{sub 2}O{sub 8} concentration, pH of the buffer on the ECL intensity have also been discussed in detail. The experiment results showed that the limit of detection for NA was 6.0×10{sup −7} M (S/N=3) with a linear range of 2.0×10{sup −6}–2.0×10{sup −4} M. - Highlights: • A novel ECL material Tb{sub 2}(H{sub 2}O){sub 4}(C{sub 6}NO{sub 2}H{sub 4}){sub 6} was synthesized and characterized. • The ECL property of the terbium chelate has been studied detail, and possible mechanism was been proposed. • A new ECL method for the determination of nicotinic acid with a wide liner range and a low detection limit was proposed.

Radiochemical separation of Tb-149 after tandem accelerator production

International Nuclear Information System (INIS)

Sarkar, S.R.

1996-01-01

Full text: Terbium-149 is produced by the heavy ion induced reaction of the type 142 Nd( 12 C,5n) 149 Dy→ 149 Tb. This work concerns the separation of terbium from neodymium target, and other lanthanides produced by secondary reactions on neodymium target. Firstly, anion-exchange separation is carried out at room temperature using acid-alcohol media (90% methanol-10% 5M nitric acid) as eluent. But the separation is not satisfactory. To achieve satisfactory separation, cation exchange separation is performed under pressure at room temperature using 0.1 6M α-hydroxyisobutyric acid of pH 5 as eluent. The pressure is exerted from a nitrogen gas cylinder. The simplicity and efficacy of this method for the separation of terbium are discussed in comparison with the commercially available high performance liquid chromatography system

Investigation of the chemistry of the dielectric/FeCoTb interface by x-ray photoelectron spectroscopy and Auger electron spectroscopy

International Nuclear Information System (INIS)

Stickle, W.F.; Coulman, D.

1987-01-01

The interfacial chemistry of magneto-optic structures of sputter deposited SiO, SiO 2 , Si 3 N 4 /FeCoTb/SiO, SiO 2 , and Si 3 N 4 was studied in detail by x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). XPS and AES depth profiles have revealed a substantial amount of redox chemistry at the dielectric/rare-earth transition metal interfaces. The chemical reactions occur preferentially with the terbium as revealed in the XPS portion of the study by the formation of terbium oxide and terbium silicide. In the case of Si 3 N 4 evidence of TbN/sub x/ has also been observed. ''As deposited'' and annealed samples of the magneto-optic structures are compared and contrasted. It is concluded that Si 3 N 4 is a superior dielectric for magneto-optic media

Lanthanides-clay nanocomposites: Synthesis, characterization and optical properties

International Nuclear Information System (INIS)

Celedon, Salvador; Quiroz, Carolina; Gonzalez, Guillermo; Sotomayor Torres, Clivia M.; Benavente, Eglantina

2009-01-01

Complexes of Europium(III) and Terbium(III) with 2,2-bipyridine and 1,10-phenanthroline were inserted into Na-bentonite by ion exchange reactions at room temperature. The products display interlaminar distances and stoichiometries in agreement with the ion exchange capacity and the interlayer space available in the clay. The optical properties of the intercalates, being qualitatively similar to those of the free complexes, are additionally improved with respect to exchange processes with the medium, especially in a moist environment. The protection again hydrolysis, together with the intensity of the optical transition 5 D 0 - 5 F 2 observed in the nanocomposite, makes these products promising for the development of novel optical materials

Reactive Chemical Vapor Deposition Method as New Approach for Obtaining Electroluminescent Thin Film Materials

Directory of Open Access Journals (Sweden)

Valentina V. Utochnikova

2012-01-01

Full Text Available The new reactive chemical vapor deposition (RCVD method has been proposed for thin film deposition of luminescent nonvolatile lanthanide aromatic carboxylates. This method is based on metathesis reaction between the vapors of volatile lanthanide dipivaloylmethanate (Ln(dpm3 and carboxylic acid (HCarb orH2Carb′ and was successfully used in case of HCarb. Advantages of the method were demonstrated on example of terbium benzoate (Tb(bz3 and o-phenoxybenzoate thin films, and Tb(bz3 thin films were successfully examined in the OLED with the following structure glass/ITO/PEDOT:PSS/TPD/Tb(bz3/Ca/Al. Electroluminescence spectra of Tb(bz3 showed only typical luminescent bands, originated from transitions of the terbium ion. Method peculiarities for deposition of compounds of dibasic acids H2Carb′ are established on example of terbium and europium terephtalates and europium 2,6-naphtalenedicarboxylate.

Simultaneous Patterning of Independent Metal/Metal Oxide Multi-Layer Films Using Two-Tone Photo-Acid Generating Compound Systems

Directory of Open Access Journals (Sweden)

Hideo Honma

2012-10-01

Full Text Available (1 The photo-induced solubility and positive-tone direct photo-patterning of iron, copper and lanthanides chelated with 4-(2-nitrobenzyloxycarbonylcatechol (NBOC or 4-(6-nitroveratryloxycarbonylcatechol (NVOC was investigated. Photo-patterning of iron, copper, cerium, samarium, europium, terbium, dysprosium, holmium, erbium and lutetium complexes was accomplished. Continuous films were formed by the pyrolysis of metal complex films at 500 °C. (2 Based on the difference in the photo-reaction excitation wavelength profile of NBOC and NVOC complexes, a short and simple method for simultaneous micro-patterning of two independent films on each side of a transparent glass substrate was developed. Using the developed procedure, indium tin oxide and/or titanium oxide films were formed on each side of a quartz substrate without use of resist or etching.

Dynamics of metal-humate complexation equilibria as revealed by isotope exchange studies - a matter of concentration and time

Science.gov (United States)

Lippold, Holger; Eidner, Sascha; Kumke, Michael U.; Lippmann-Pipke, Johanna

2017-01-01

Complexation with dissolved humic matter can be crucial in controlling the mobility of toxic or radioactive contaminant metals. For speciation and transport modelling, a dynamic equilibrium process is commonly assumed, where association and dissociation run permanently. This is, however, questionable in view of reported observations of a growing resistance to dissociation over time. In this study, the isotope exchange principle was employed to gain direct insight into the dynamics of the complexation equilibrium, including kinetic inertisation phenomena. Terbium(III), an analogue of trivalent actinides, was used as a representative of higher-valent metals. Isotherms of binding to (flocculated) humic acid, determined by means of 160Tb as a radiotracer, were found to be identical regardless of whether the radioisotope was introduced together with the bulk of stable 159Tb or subsequently after pre-equilibration for up to 3 months. Consequently, there is a permanent exchange of free and humic-bound Tb since all available binding sites are occupied in the plateau region of the isotherm. The existence of a dynamic equilibrium was thus evidenced. There was no indication of an inertisation under these experimental conditions. If the small amount of 160Tb was introduced prior to saturation with 159Tb, the expected partial desorption of 160Tb occurred at much lower rates than observed for the equilibration process in the reverse procedure. In addition, the rates decreased with time of pre-equilibration. Inertisation phenomena are thus confined to the stronger sites of humic molecules (occupied at low metal concentrations). Analysing the time-dependent course of isotope exchange according to first-order kinetics indicated that up to 3 years are needed to attain equilibrium. Since, however, metal-humic interaction remains reversible, exchange of metals between humic carriers and mineral surfaces cannot be neglected on the long time scale to be considered in predictive

Scanning Electron Microscope-Cathodoluminescence Analysis of Rare-Earth Elements in Magnets.

Science.gov (United States)

Imashuku, Susumu; Wagatsuma, Kazuaki; Kawai, Jun

2016-02-01

Scanning electron microscope-cathodoluminescence (SEM-CL) analysis was performed for neodymium-iron-boron (NdFeB) and samarium-cobalt (Sm-Co) magnets to analyze the rare-earth elements present in the magnets. We examined the advantages of SEM-CL analysis over conventional analytical methods such as SEM-energy-dispersive X-ray (EDX) spectroscopy and SEM-wavelength-dispersive X-ray (WDX) spectroscopy for elemental analysis of rare-earth elements in NdFeB magnets. Luminescence spectra of chloride compounds of elements in the magnets were measured by the SEM-CL method. Chloride compounds were obtained by the dropwise addition of hydrochloric acid on the magnets followed by drying in vacuum. Neodymium, praseodymium, terbium, and dysprosium were separately detected in the NdFeB magnets, and samarium was detected in the Sm-Co magnet by the SEM-CL method. In contrast, it was difficult to distinguish terbium and dysprosium in the NdFeB magnet with a dysprosium concentration of 1.05 wt% by conventional SEM-EDX analysis. Terbium with a concentration of 0.02 wt% in an NdFeB magnet was detected by SEM-CL analysis, but not by conventional SEM-WDX analysis. SEM-CL analysis is advantageous over conventional SEM-EDX and SEM-WDX analyses for detecting trace rare-earth elements in NdFeB magnets, particularly dysprosium and terbium.

Dual lanthanide-doped complexes: the development of a time-resolved ratiometric fluorescent probe for anthrax biomarker and a paper-based visual sensor.

Science.gov (United States)

Wang, Qi-Xian; Xue, Shi-Fan; Chen, Zi-Han; Ma, Shi-Hui; Zhang, Shengqiang; Shi, Guoyue; Zhang, Min

2017-08-15

In this work, a novel time-resolved ratiometric fluorescent probe based on dual lanthanide (Tb: terbium, and Eu: europium)-doped complexes (Tb/DPA@SiO 2 -Eu/GMP) has been designed for detecting anthrax biomarker (dipicolinic acid, DPA), a unique and major component of anthrax spores. In such complexes-based probe, Tb/DPA@SiO 2 can serve as a stable reference signal with green fluorescence and Eu/GMP act as a sensitive response signal with red fluorescence for ratiometric fluorescent sensing DPA. Additionally, the probe exhibits long fluorescence lifetime, which can significantly reduce the autofluorescence interferences from biological samples by using time-resolved fluorescence measurement. More significantly, a paper-based visual sensor for DPA has been devised by using filter paper embedded with Tb/DPA@SiO 2 -Eu/GMP, and we have proved its utility for fluorescent detection of DPA, in which only a handheld UV lamp is used. In the presence of DPA, the paper-based visual sensor, illuminated by a handheld UV lamp, would result in an obvious fluorescence color change from green to red, which can be easily observed with naked eyes. The paper-based visual sensor is stable, portable, disposable, cost-effective and easy-to-use. The feasibility of using a smartphone with easy-to-access color-scanning APP as the detection platform for quantitative scanometric assays has been also demonstrated by coupled with our proposed paper-based visual sensor. This work unveils an effective method for accurate, sensitive and selective monitoring anthrax biomarker with backgroud-free and self-calibrating properties. Copyright © 2017 Elsevier B.V. All rights reserved.

Cermet electrode

Science.gov (United States)

Maskalick, Nicholas J.

1988-08-30

Disclosed is a cermet electrode consisting of metal particles of nickel, cobalt, iron, or alloys or mixtures thereof immobilized by zirconia stabilized in cubic form which contains discrete deposits of about 0.1 to about 5% by weight of praseodymium, dysprosium, terbium, or a mixture thereof. The solid oxide electrode can be made by covering a substrate with particles of nickel, cobalt, iron, or mixtures thereof, growing a stabilized zirconia solid oxide skeleton around the particles thereby immobilizing them, contacting the skeleton with a compound of praseodymium, dysprosium, terbium, or a mixture thereof, and heating the skeleton to a temperature of at least 500.degree. C. The electrode can also be made by preparing a slurry of nickel, cobalt, iron, or mixture and a compound of praseodymium, dysprosium, terbium, or a mixture thereof, depositing the slurry on a substrate, heating the slurry to dryness, and growing a stabilized zirconia skeleton around the metal particles.

A luminescence-based probe for sensitive detection of hydrogen peroxide in seconds

International Nuclear Information System (INIS)

Zscharnack, Kristin; Kreisig, Thomas; Prasse, Agneta A.; Zuchner, Thole

2014-01-01

Highlights: • We describe a novel probe for the sensitive detection of H 2 O 2 . • H 2 O 2 quenches the luminescence of a complex consisting of phthalic acid and terbium ions. • A stable fluorescence signal is generated immediately after mixing probe and sample. • The PATb probe detects H 2 O 2 over four orders of magnitude. - Abstract: Here, we present a fast and simple hydrogen peroxide assay that is based on time-resolved fluorescence. The emission intensity of a complex consisting of terbium ions (Tb 3+ ) and phthalic acid (PA) in HEPES buffer is quenched in the presence of H 2 O 2 and this quenching is concentration-dependent. The novel PATb assay detects hydrogen peroxide at a pH range from 7.5 to 8.5 and with a detection limit of 150 nmol L −1 at pH 8.5. The total assay time is less than 1 min. The linear range of the assay can be adapted by a pH adjustment of the aqueous buffer and covers a concentration range from 310 nmol L −1 to 2.56 mmol L −1 in total which encompasses four orders of magnitude. The assay is compatible with high concentrations of all 47 tested inorganic and organic compounds. The PATb assay was applied to quantify H 2 O 2 in polluted river water samples. In conclusion, this fast and easy-to-use assay detects H 2 O 2 with high sensitivity and precision

Highly Luminescent, Water-Soluble Lanthanide Fluorobenzoates: Syntheses, Structures and Photophysics, Part I: Lanthanide Pentafluorobenzoates.

Science.gov (United States)

Kalyakina, Alena S; Utochnikova, Valentina V; Bushmarinov, Ivan S; Ananyev, Ivan V; Eremenko, Igor L; Volz, Daniel; Rönicke, Franziska; Schepers, Ute; Van Deun, Rik; Trigub, Alexander L; Zubavichus, Yan V; Kuzmina, Natalia P; Bräse, Stefan

2015-12-01

Highly luminescent, photostable, and soluble lanthanide pentafluorobenzoates have been synthesized and thoroughly characterized, with a focus on Eu(III) and Tb(III) complexes as visible emitters and Nd(III) , Er(III) , and Yb(III) complexes as infrared emitters. Investigation of the crystal structures of the complexes in powder form and as single crystals by using X-ray diffraction revealed five different structural types, including monomeric, dimeric, and polymeric. The local structure in different solutions was studied by using X-ray absorption spectroscopy. The photoluminescence quantum yields (PLQYs) of terbium and europium complexes were 39 and 15 %, respectively; the latter value was increased almost twice by using the heterometallic complex [Tb0.5 Eu0.5 (pfb)3 (H2 O)] (Hpfb=pentafluorobenzoic acid). Due to the effectively utilized sensitization strategy (pfb)(-) →Tb→Eu, a pure europium luminescence with a PLQY of 29 % was achieved. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Preparation and photoluminescence characteristics of In(OH){sub 3}:xTb{sup 3+} obtained by Microwave-Assisted Hydrothermal method

Energy Technology Data Exchange (ETDEWEB)

Motta, F.V., E-mail: fabiana@ct.ufrn.br [DEMAT, CT, UFRN, Av. Sen. Salgado Filho 3000, CEP 59072-970 Natal, RN (Brazil); Marques, A.P.A. [UNIFESP, Rua Prof. Artur Riedel 275, CEP 09972-270 Diadema, SP (Brazil); Li, M.S. [IFSC, USP, Av. Trabalhador São Carlense 400, CEP 13566-590 São Carlos, SP (Brazil); Abreu, M.F.C. [LIEC, DQ, UFSCar, Via Washington Luiz, km 235, CEP 13565-905 São Carlos, SP (Brazil); Paskocimas, C.A.; Bomio, M.R.D. [DEMAT, CT, UFRN, Av. Sen. Salgado Filho 3000, CEP 59072-970 Natal, RN (Brazil); Souza, R.P. [DEP, CT, UFRN, Av. Sen. Salgado Filho 3000, CEP 59072-970 Natal, RN (Brazil); Varela, J.A. [LIEC, IQ, UNESP, Rua Francisco Degni s/n, CEP 14801-907 Araraquara, SP (Brazil); Longo, E. [LIEC, DQ, UFSCar, Via Washington Luiz, km 235, CEP 13565-905 São Carlos, SP (Brazil)

2013-03-15

Highlights: ► We report the preparation by Microwave-Hydrothermal method of In(OH){sub 3}:xTb{sup 3+}. ► Nanostructures were obtained at a low temperature. ► The crystallite size decreased with terbium doping level. ► The nucleation–dissolution–recrystallization mechanism is promoted by processing. ► This material is a highly promising candidate for photoluminescent applications. -- Abstract: Crystalline terbium-doped indium hydroxide structures were prepared by a rapid and efficient Microwave-Assisted Hydrothermal (MAH) method. Nanostructures were obtained at a low temperature. FE-SEM images confirm that these samples are composed of 3D nanostructures. XRD, optical diffuse reflectance and photoluminescence (PL) measurements were used to characterize the products. Emission spectra of terbium-doped indium hydroxide (In(OH){sub 3}:xTb{sup 3+}) samples under excitation (350.7 nm) presented broad band emission referent to the indium hydroxide matrix and {sup 5}D{sub 4} → {sup 7}F{sub 6}, {sup 5}D{sub 4} → {sup 7}F{sub 5}, {sup 5}D{sub 4} → {sup 7}F{sub 4}, and {sup 5}D{sub 4} → {sup 7}F{sub 3} terbium transitions at 495, 550, 590 and 627 nm, respectively. Relative intensities of the Tb{sup 3+} emissions increased as the concentration of this ion increased from 0, 1, 2, 4 and 8 mol%, of Tb{sup 3+}, but the luminescence is drastically quenched for the In(OH){sub 3} matrix.

Determination of Rare Earth Elements in plants by neutron activation analysis

International Nuclear Information System (INIS)

Figueiredo, Ana M.G.; Maria, Sheila P.; Ceccantini, Gregorio C.T.

1996-01-01

In the present work, instrumental neutron activation analysis was employed to the determination of rare earth elements (La, Ce, Nd, Eu, Tb, Yb e Lu) in plants, aiming biogeochemical studies. The precision and accuracy of the method were verified by the analysis of the reference materials Citrus Leaves (NIST 1572) and Pine Needles (NIST 1575). With exception of terbium, the results obtained agreed with reference values, giving relative errors less than 25%. The method was applied to different species of plants growing in the alkaline-ultramafic complex of Salitre, MG and the obtained data were compared to the average content in plants. (author)

Extraction of nitrates of lanthanoids (3) of the yttrium group and yttrium (3) by trialkylbenzylammonium nitrate in toluene

International Nuclear Information System (INIS)

Pyartman, A.K.; Kovalev, S.V.; Keskinov, V.A.; Kopyrin, A.A.

1997-01-01

A study was made on extraction of nitrates of lanthanoids (3) of the yttrium group (terbium-lutetium) and yttrium (3) by trialkylbensylammonium nitrate in toluene at T=298.15 K pH 2. Extraction isotherms are described with account of formation of compound of (R 4 N) 2 [Ln(NO 3 ) 5 ] composition in organic phase. Values of extraction constants decreasing in terbium (3)-lutetium (3) series, were calculated. Value of extraction constant for yttrium (3) is close to the value of extraction constant for ytterbium (3). 13 refs., 2 figs., 3 tabs

Kinetic study of Tb/sup 3 +/(/sup 5/D/sub 3/) luminescence in phosphate glasses

Energy Technology Data Exchange (ETDEWEB)

Anisimov, V.A.; Dmitryuk, A.V.; Karapetyan, G.O.

1986-01-01

This paper presents precise determinations of the kinetics of terbium luminescence over a broad dynamic range, in order to refine the mechanism of concentration quenching of the Tb/sup 3 +/(/sup 5/D/sub 3/) luminescence in glasses. After establishing the mechanism of Tb/sup 3 +/(/sup 5/D/sub 3/) luminescence quenching by the iteration method, the authors determine the value of the parameter for an arbitrary concentration of the activator. Results of this study show that the mechanism of concentration quenching of luminescence is static dipole-dipole interaction of terbium ions.

Time-Resolved Analysis of a Highly Sensitive Förster Resonance Energy Transfer Immunoassay Using Terbium Complexes as Donors and Quantum Dots as Acceptors

Directory of Open Access Journals (Sweden)

Niko Hildebrandt

2007-01-01

Full Text Available CdSe/ZnS core/shell quantum dots (QDs are used as efficient Förster Resonance Energy Transfer (FRET acceptors in a time-resolved immunoassays with Tb complexes as donors providing a long-lived luminescence decay. A detailed decay time analysis of the FRET process is presented. QD FRET sensitization is evidenced by a more than 1000-fold increase of the QD luminescence decay time reaching ca. 0.5 milliseconds, the same value to which the Tb donor decay time is quenched due to FRET to the QD acceptors. The FRET system has an extremely large Förster radius of approx. 100 Å and more than 70% FRET efficiency with a mean donor-acceptor distance of ca. 84 Å, confirming the applied biotin-streptavidin binding system. Time-resolved measurement allows for suppression of short-lived emission due to background fluorescence and directly excited QDs. By this means a detection limit of 18 attomol QDs within the immunoassay is accomplished, an improvement of more than two orders of magnitude compared to commercial systems.

The crystal structure and luminescence quenching of poly- and single-crystalline KYW{sub 2}O{sub 8}:Tb{sup 3+}

Energy Technology Data Exchange (ETDEWEB)

Schwung, Sebastian [Fachbereich Chemieingenieurwesen, Fachhochschule Münster, Stegerwaldstraße 39, 48565 Steinfurt (Germany); Rytz, Daniel, E-mail: rytz@fee-io.de [Forschungsinstitut für mineralische und metallische Werkstoffe-Edelsteine/ Edelmetalle-GmbH (FEE), Struthstraße 2, 55743 Idar-Oberstein (Germany); Heying, Birgit; Rodewald, Ute Ch.; Niehaus, Oliver [Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstrasse 30 48149 Münster (Germany); Enseling, David [Fachbereich Chemieingenieurwesen, Fachhochschule Münster, Stegerwaldstraße 39, 48565 Steinfurt (Germany); Jüstel, Thomas, E-mail: tj@fh-muenster.de [Fachbereich Chemieingenieurwesen, Fachhochschule Münster, Stegerwaldstraße 39, 48565 Steinfurt (Germany); Pöttgen, Rainer, E-mail: pottgen@uni-muenster.de [Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstrasse 30 48149 Münster (Germany)

2015-10-15

Terbium-substituted KYW{sub 2}O{sub 8} single crystals of high optical quality were grown by the top seeded solution growth technique. The degree of yttrium–terbium mixed occupancy was determined for two samples through structure refinements on the basis of single crystal X-ray diffractometer data. Temperature dependent magnetic susceptibility data underline the paramagnetic nature of terbium doped crystals. No magnetic ordering is evident down to 2 K. Luminescence measurements yield the typical excitation and emission spectra as expected for Tb{sup 3+} activated materials. The decay time of Tb{sup 3+} decreases linearly with the Tb{sup 3+} concentration, while the excess of thermal quenching does not change significantly. At about 405 K the decay time is reduced by roughly 50% relative to the low-temperature value, both for the powders as for the single crystals. - Highlights: • Single crystalline and powder series of K(Y,Tb)W{sub 2}O{sub 8.} • Refined XRD data of high quality crystals. • Linear decrease of the decay time with Tb{sup 3+} content.

Time-resolved fluorescence sensing of N-acetyl amino acids, nucleobases, nucleotides and DNA by the luminescent Tb (III) - 8-alkyl-2-oxo-2H-chromene-3-carbaldehyde probe

Energy Technology Data Exchange (ETDEWEB)

Azab, Hassan A. [Chemistry Department, Faculty of Science, Suez Canal University, 41522 Ismailia (Egypt); Khairy, Gasser M., E-mail: gasser_chemist@yahoo.com [Chemistry Department, Faculty of Science and Arts, Aljouf University, P.O. Box # 2014, Skaka 41421 (Saudi Arabia); Chemistry Department, Faculty of Science, Suez Canal University, 41522 Ismailia (Egypt); Abd El-Ghany, N.; Ahmed, Marwa A. [Chemistry Department, Faculty of Science, Suez Canal University, El-Arish (Egypt)

2016-08-15

A time-resolved (gated) luminescence-based method for the detection of some of N-acetyl amino acids, nucleobases, nucleotides, and DNA using terbium- 8-alkyl-2-oxo-2H-chromene-3-carbaldehyde (AOCC) complex in 1:2 metal: ligand ratio in microtiterplate format has been evolved. The linear range for determination of the selected biomolecules is 0.1–1.0 µM. The detection limit was in the range of 0.0371–0.106 µM. The thermodynamic parameters, and binding constants (K) of N-acetyl amino acids, nucleobases, nucleotides with Tb (III) –(AOCC) {sub 2} complex were calculated. Positive and negative values of entropy (ΔS) and enthalpy (ΔH) changes for Tb (III) –(AOCC){sub 2}– N-acetyl amino acids, nucleobases or nucleotides ternary complexes were evaluated. Selectivity of Tb (III) -complex towards different biomolecules has been studied using ratiometric methods of analysis by comparison of biomolecules binding affinities for Tb (III) -complex. Interaction of Tb (III) complex with DNA has been studied.

Time-resolved fluorescence sensing of N-acetyl amino acids, nucleobases, nucleotides and DNA by the luminescent Tb (III) - 8-alkyl-2-oxo-2H-chromene-3-carbaldehyde probe

International Nuclear Information System (INIS)

Azab, Hassan A.; Khairy, Gasser M.; Abd El-Ghany, N.; Ahmed, Marwa A.

2016-01-01

A time-resolved (gated) luminescence-based method for the detection of some of N-acetyl amino acids, nucleobases, nucleotides, and DNA using terbium- 8-alkyl-2-oxo-2H-chromene-3-carbaldehyde (AOCC) complex in 1:2 metal: ligand ratio in microtiterplate format has been evolved. The linear range for determination of the selected biomolecules is 0.1–1.0 µM. The detection limit was in the range of 0.0371–0.106 µM. The thermodynamic parameters, and binding constants (K) of N-acetyl amino acids, nucleobases, nucleotides with Tb (III) –(AOCC) 2 complex were calculated. Positive and negative values of entropy (ΔS) and enthalpy (ΔH) changes for Tb (III) –(AOCC) 2 – N-acetyl amino acids, nucleobases or nucleotides ternary complexes were evaluated. Selectivity of Tb (III) -complex towards different biomolecules has been studied using ratiometric methods of analysis by comparison of biomolecules binding affinities for Tb (III) -complex. Interaction of Tb (III) complex with DNA has been studied.

Dynamics of trivalent rare earth molecular vapor lasers

International Nuclear Information System (INIS)

Krupke, W.F.

1976-01-01

Radiative transition probabilities in neodymium bearing vapors are reviewed and calculations are extended to visible laser transitions in terbium bearing vapor. Nonradiative relaxation processes in the pure and complexed halides are treated in greater detail. While precise, quantitative relaxation probabilities cannot be calculated on the basis of information presently available, plausibility arguments can be established which indicate the order of magnitude of relevant nonradiative decay probabilities. Reference to solid and liquid state nonradiative relaxation data for rare earth ions is reviewed to support the plausibility arguments for the vapor state. Having established the likelihood of high fluorescence yields in the vapor phase, various methods of laser pumping are discussed: optical pumping via parity allowed 4f-5d transitions; optical pumping via charge transfer bands of the vapor complex; and direct electron beam pumping

Synthesis and characterization of multifunctional silica core-shell nanocomposites with magnetic and fluorescent functionalities

International Nuclear Information System (INIS)

Ma Zhiya; Dosev, Dosi; Nichkova, Mikaela; Dumas, Randy K.; Gee, Shirley J.; Hammock, Bruce D.; Liu Kai; Kennedy, Ian M.

2009-01-01

Multifunctional core-shell nanocomposites with a magnetic core and a silica shell doped with lanthanide chelate have been prepared by a simple method. First, citric acid-modified magnetite nanoparticles were synthesized by a chemical coprecipitation method. Then the magnetite nanoparticles were coated with silica shells doped with terbium (Tb 3+ ) complex by a modified Stoeber method based on hydrolyzing and condensation of tetraethyl orthosilicate (TEOS) and a silane precursor. These multifunctional nanocomposites are potentially useful in a variety of biological areas such as bio-imaging, bio-labeling and bioassays because they can be simultaneously manipulated with an external magnetic field and exhibit unique phosphorescence properties.

Reversed-phase thin-layer chromatography of the rare earth elements

International Nuclear Information System (INIS)

Kuroda, R.; Adachi, M.; Oguma, K.

1988-01-01

Partition chromatographic behaviour of the rare earth elements on C 18 bonded silica reversed-phase material has been investigated by thin-layer chromatography in methanol - lactate media. The rare earth lactato complexes are distributed and fractionated on bonded silica layers without ion-interaction reagents. The concentration and pH of lactate solution, methanol concentration and temperature have effects on the migration and resolution of the rare earth elements. The partition system is particularly suited to separate adjacent rare earths of middle atomic weight groups, allowing the separation of gadolinium, terbium, dysprosium, holmium, erbium and thulium to be achieved by development to 18 cm distance. (orig.)

A scanning tunneling microscopy study of the electronic and spin states of bis(phthalocyaninato)terbium(iii) (TbPc2) molecules on Ag(111).

Science.gov (United States)

Ara, Ferdous; Qi, Zhi Kun; Hou, Jie; Komeda, Tadahiro; Katoh, Keiichi; Yamashita, Masahiro

2016-10-25

In this article, we investigate a single molecule magnet bis(phthalocyaninato)terbium(iii) (TbPc 2 ) molecule film by using low temperature STM. In order to investigate the effect of molecule-substrate interaction on the electronic and spin properties of the adsorbed molecule, we tune the molecule-substrate coupling by switching the substrate between Au(111) and Ag(111), the latter of which provides stronger interaction with the molecule than the former. Despite the enhanced chemical reactivity of the Ag(111) surface compared with Au(111), a well-organized pseudo-square film is formed. In addition, a checker-board type contrast variation is identified, which is well explained by the existence of two types of molecules whose rotational angle between the top and bottom Pc is θ = 45° (bright molecule) and θ = 30° (dark molecule). The expected stronger molecule-substrate interaction, however, appears as an intriguing dI/dV mapping image which reveals the spatial distribution of the density of states (DOS). We identify the contrast reversal in the dI/dV mapping for the molecules of θ = 45° and θ = 30° at the sample voltages of V = 0.7 eV and 1.1 eV. Combined with the density functional theory (DFT) calculation, we attribute this change to the shift of an electronic state due to the rotation of the mutual angle between the top and bottom Pc. For the spin behavior, we previously observed a Kondo resonance for the TbPc 2 molecule adsorbed on the Au(111) surface. On the Ag(111) surface, the Kondo resonance is hardly observed, which is due to the annihilation of the π radical spin by the charge transfer from the substrate to the molecule. Instead we observe a Kondo peak for the molecule on the second layer, for which the spin recovers due to the reduction of the coupling with the substrate. In addition, when a magnetic field of 2 T normal to the surface is applied, the second layer molecule shows a sharp dip at the Fermi level. We attribute this to the inelastic

Determination of adenosine disodium triphosphate using prulifloxacin-terbium(III) as a fluorescence probe by spectrofluorimetry

International Nuclear Information System (INIS)

Yu Fengshan; Li Lin; Chen Fang

2008-01-01

A new spectrofluorimetric method is developed for determination of adenosine disodium triphosphate (ATP). The interactions between prulifloxacin (PUFX)-Tb 3+ complex and adenosine disodium triphosphate has been studied by using UV-vis absorption and fluorescence spectra. Using prulifloxacin-Tb 3+ as a fluorescence probe, under the optimum conditions, ATP can remarkably enhance the fluorescence intensity of the prulifloxacin-Tb 3+ complex at λ = 545 nm and the enhanced fluorescence intensity is in proportion to the concentration of ATP. Optimum conditions for the determination of ATP were also investigated. The dynamic range for the determination of ATP is 4.0 x 10 -7 to 2.0 x 10 -5 mol L -1 , and the detection limit (3 σ/k) is 1.7 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 ATP in real pharmaceutical samples. The mechanism of fluorescence enhancement of prulifloxacin-Tb 3+ complex by ATP was also discussed

Determination of active oxygen content in rare earth peroxides

International Nuclear Information System (INIS)

Queiroz, Carlos A.S.; Abrao, Alcidio

1993-01-01

The content of active oxygen in rare earth peroxides have been determined after the dissolution of the samples with hydrocloridic acid in the presence of potassium iodide. The free generated iodine is titrated with sodium thiosulfate using starch as indicator. The oxidation of iodide to the free iodine indicates the presence of a higher valence state rare earth oxide, until now specifically recognized for the oxides of cerium (Ce O 2 ), praseodymium (Pr 6 O 1 1) and terbium (TB 4 O 7 ). recently the authors synthesized a new series of rare earth compounds, the peroxides. These new compounds were prepared by precipitating the rare earth elements complexed with carbonate ion by addition of hydrogen peroxide. the authors demonstrated that all rare earth elements, once solubilized by complexing with carbonate ion, are quantitatively precipitated as peroxide by addition of hydrogen peroxide. (author)

Assessment of terbium (III) as a luminescent probe for the detection of tuberculosis biomarkers

International Nuclear Information System (INIS)

Bamogo, W.; Mugherli, L.; Banyasz, A.; Novelli-Rousseau, A.; Mallard, F.; Tran-Thi, T.-H.

2015-01-01

A detection method for nicotinic acid, a specific metabolite marker of Mycobacterium tuberculosis present in cultures and patients' breath, is studied in complex solutions containing other metabolites and in biological media such as urine, saliva and breath condensate. The method is based on the analysis of the luminescence increase of Tb 3+ complexes in the presence of nicotinic acid due to the energy transfer from the excited ligand to the lanthanide ion. It is shown that other potential markers found in M. tuberculosis culture supernatant, such as methyl phenylacetate, p-methyl anisate, methyl nicotinate and 2-methoxy biphenyl, can interfere with nicotinic acid via a competitive absorption of the excitation photons. A new strategy to circumvent these interferences is proposed with an upstream trapping of volatile markers preceding the detection of nicotinic acid in the liquid phase via the luminescence of Tb 3+ complexes. The cost of the method is evaluated and compared with the Xpert MTB/RIF test endorsed by the World Health Organization. - Highlights: • Nicotinic acid, a specific marker of M. tuberculosis, can be detected via luminescence. • The detection limit with a commercial phosphorimeter is 0.4 µmol·L -1 . • Other metabolites of M. tuberculosis can interfere via absorbed excitation light. • The interference can be removed via trapping of the most volatile metabolites. • A breath analysis procedure's cost is compared with the Xpert TBM/RIF test.

Assessment of terbium (III) as a luminescent probe for the detection of tuberculosis biomarkers

Energy Technology Data Exchange (ETDEWEB)

Bamogo, W. [CNRS, IRAMIS, UMR 3685 NIMBE/LEDNA, F-91191 Gif-sur-Yvette (France); Mugherli, L. [CEA, IRAMIS, UMR 3685 NIMBE/LEDNA, F-91191 Gif-sur-Yvette (France); Banyasz, A. [CNRS, IRAMIS, LIDyL/Laboratoire Francis Perrin, URA 2453, F-91191 Gif-sur-Yvette (France); Novelli-Rousseau, A.; Mallard, F. [BioMérieux SA, F-38000 Grenoble (France); Tran-Thi, T.-H., E-mail: thu-hoa.tran-thi@cea.fr [CNRS, IRAMIS, UMR 3685 NIMBE/LEDNA, F-91191 Gif-sur-Yvette (France)

2015-10-08

A detection method for nicotinic acid, a specific metabolite marker of Mycobacterium tuberculosis present in cultures and patients' breath, is studied in complex solutions containing other metabolites and in biological media such as urine, saliva and breath condensate. The method is based on the analysis of the luminescence increase of Tb{sup 3+} complexes in the presence of nicotinic acid due to the energy transfer from the excited ligand to the lanthanide ion. It is shown that other potential markers found in M. tuberculosis culture supernatant, such as methyl phenylacetate, p-methyl anisate, methyl nicotinate and 2-methoxy biphenyl, can interfere with nicotinic acid via a competitive absorption of the excitation photons. A new strategy to circumvent these interferences is proposed with an upstream trapping of volatile markers preceding the detection of nicotinic acid in the liquid phase via the luminescence of Tb{sup 3+} complexes. The cost of the method is evaluated and compared with the Xpert MTB/RIF test endorsed by the World Health Organization. - Highlights: • Nicotinic acid, a specific marker of M. tuberculosis, can be detected via luminescence. • The detection limit with a commercial phosphorimeter is 0.4 µmol·L{sup -1}. • Other metabolites of M. tuberculosis can interfere via absorbed excitation light. • The interference can be removed via trapping of the most volatile metabolites. • A breath analysis procedure's cost is compared with the Xpert TBM/RIF test.

Magnon Interactions in Terbium

DEFF Research Database (Denmark)

Nielsen, Mourits; Bjerrum Møller, Hans; Mackintosh, Allan

1970-01-01

Magnon energies and lifetimes have been studied in Tb and Tb-10% Ho single crystals by inelastic neutron scattering. The lifetimes of magnons propagating in the c-direction have been measured in the ferromagnetic phase of Tb, and are found to decrease with increasing temperature and wave......-vector, probably principally due to magnon-magnon interactions. The interaction of magnons with phonons has also been observed and the effect of Ho impurities on this interaction studied. In addition, excitations which are ascribed to local modes associated with the Ho ions have been observed. The dependence...... of the indirect exchange interaction on temperature in the alloy gives information on the mechanisms responsible for the transition from the helical to ferromagnetic structures. The dependence of the magnon energies on magnetic field at low temperatures gives detailed information on the role of magnetoelastic...

Spin Waves in Terbium

DEFF Research Database (Denmark)

Jensen, J.; Houmann, Jens Christian Gylden; Bjerrum Møller, Hans

1975-01-01

with the symmetry, we deduce the dispersion relation for the spin waves in a basal-plane ferromagnet. This phenomenological spin-wave theory accounts for the observed behavior of the magnon energies in Tb. The two q⃗-dependent Bogoliubov components of the magnon energies are derived from the experimental results......, which are corrected for the effect of the direct coupling between the magnons and the phonons, and for the field dependence of the relative magnetization at finite temperatures. A large q⃗-dependent difference between the two energy components is observed, showing that the anisotropy of the two...

Spin Waves in Terbium

DEFF Research Database (Denmark)

Jensen, J.; Houmann, Jens Christian Gylden

1975-01-01

The selection rules for the linear couplings between magnons and phonons propagating in the c direction of a simple basal-plane hcp ferromagnet are determined by general symmetry considerations. The acoustic-optical magnon-phonon interactions observed in the heavy-rare-earth metals have been...... explained by Liu as originating from the mixing of the spin states of the conduction electrons due to the spin-orbit coupling. We find that this coupling mechanism introduces interactions which violate the selection rules for a simple ferromagnet. The interactions between the magnons and phonons propagating...... in the c direction of Tb have been studied experimentally by means of inelastic neutron scattering. The magnons are coupled to both the acoustic- and optical-transverse phonons. By studying the behavior of the acoustic-optical coupling, we conclude that it is a spin-mixed-induced coupling as proposed...

Solid state chemistry of rare earth oxides. Final report, September 1, 1950--July 31, 1977

International Nuclear Information System (INIS)

Eyring, L.

1977-07-01

Work under Contract E(11-1)-1109 and its antecedents has been primarily for the purpose of obtaining detailed thermodynamic, kinetic and structural information on the complex rare earth oxides of praseodymium and terbium. These systems exhibit homologous series of ordered phases, order-disorder transformations, wide-range nonstoichiometric phases, chemical hysteresis in two-phase regions and many other solid state reaction phenomena. Fluorite-related materials of importance to ERDA occur as nuclear fuels, radiation power sources, insulators and solid electrolytes. The rare earth oxides serve directly as model systems for such similar materials and, in a more general sense, they serve as models of solids in general since they exhibit nearly the full range of solid state properties

Combination of photosensitive elements for use in radiography

International Nuclear Information System (INIS)

Bollen, R.H.; Vandenabeele, H.

1976-01-01

A new and improved combination of photosensitive elements is proposed that can be used in radiography. The combination according to the invention is composed of an X-ray fluorescence intensifying screen and a photographic halide of silver containing a color coupler. The color coupler causes a negative silver image and a color image to be formed in the material. The fluorescent layer of the fluorescence screen contains a mixture of lanthanum oxychloride or lanthanum oxybromide activated with terbium or terbium and ytterbium. Detailed information about variants in the composition of the fluorescent substance, the grain sizes of the silver halides, variations of the color couplers and about the coating of the single layers is given. (UWI) [de

Syntheses of optically efficient (La{sub 1-x-y}Ce{sub x}Tb{sub y})F{sub 3} nanocrystals via a hydrothermal method

Energy Technology Data Exchange (ETDEWEB)

Wang Qiang [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); You Yumin; Ludescher, Richard D. [Department of Food Science, Rutgers University, New Brunswick, NJ 08901 (United States); Ju Yiguang, E-mail: yju@princeton.ed [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States)

2010-06-15

Optically efficient cerium and terbium doped lanthanide fluoride (La{sub 1-x-y}Ce{sub x}Tb{sub y})F{sub 3} nanocrystals with different doping concentrations have been synthesized by a hydrothermal route in the presence of ethylenediamine tetraacetic acid disodium salt (EDTA). The results showed that the formation of nanocrystals with different morphologies depends on terbium ion Tb{sup 3+} doping concentration, but independent of cerium ion Ce{sup 3+} doping concentration. With increase in Tb{sup 3+} doping concentration, the morphologies of nanocrystals evolved from a spherical shape to a plated-like one. In addition, both the photoluminescence quantum yield (PL QY) and the fluorescence lifetime of nanocrystals increased with the increase in Ce{sup 3+} doping concentration in cerium and terbium co-doped system. The PL QY reached up to 55%, and the lifetime up to 7.3 ms. Transmission electron microscopy (TEM), X-ray diffraction (XRD), selected area electron diffraction (SAED), X-ray fluorescence (XRF), energy dispersive spectroscopy (EDS), ultraviolet-visible (UV-vis) absorption, photoluminescence (PL) and infrared (IR) spectroscopies were employed to characterize the properties of nanocrystals. The growth mechanism of nanocrystals with different morphologies and optical properties of nanocrystals with different doping concentrations were investigated.

Enhancing Sm{sup 3+} red emission via energy transfer from Bi{sup 3+}→Sm{sup 3+} based on terbium bridge mechanism in Ca{sub 2}Al{sub 2}SiO{sub 7} phosphors

Energy Technology Data Exchange (ETDEWEB)

Li, Minhong; Wang, LiLi; Ran, Weiguang; Ren, Chunyan; Song, Zeling; Shi, Jinsheng, E-mail: jsshiqn@aliyun.com

2017-04-15

Currently, the key change for white-LED is to improve the luminescence efficiency of red phosphor. Sm{sup 3+} activated phosphor was considered due to suitable emission position of red light. However, the luminescence intensity in the red region is weak. For enhancing red-emitting of Sm{sup 3+}, Bi{sup 3+} and Tb{sup 3+} ions were introduced into Ca{sub 2}Al{sub 2}SiO{sub 7}:Sm{sup 3+} phosphors based on the concept of energy transfer. For Ca{sub 2}Al{sub 2}SiO{sub 7}:Bi{sup 3+}, Sm{sup 3+} samples, it can be observed that the energy transfer process was blocked. Hence, Tb{sup 3+} was introduced into Ca{sub 2}Al{sub 2}SiO{sub 7}:Bi{sup 3+}, Sm{sup 3+} samples to increase Sm{sup 3+} luminescence intensity based on Bi{sup 3+}→Tb{sup 3+}→Sm{sup 3+} energy transfer process. Compared with Sm{sup 3+} single-doped Ca{sub 2}Al{sub 2}SiO{sub 7} phosphor, the luminescence intensity of Sm{sup 3+} was enhanced by 2.6 times. It can be found that Tb{sup 3+} ions play a role of storing the energy or transfer bridge from Bi{sup 3+}→ Sm{sup 3+} by investigating the Ca{sub 2}Al{sub 2}SiO{sub 7}:Bi{sup 3+}, Tb{sup 3+} and Ca{sub 2}Al{sub 2}SiO{sub 7}:Tb{sup 3+}, Sm{sup 3+} energy transfer mechanism. All these results suggest that terbium branch mechanism plays an important role on enhancing activators luminescence intensity.

Structure and luminescence spectra of lutetium and yttrium borates synthesized from ammonium nitrate melt

International Nuclear Information System (INIS)

Klassen, Nikolay V.; Shmurak, Semion Z.; Shmyt'ko, Ivan M.; Strukova, Galina K.; Derenzo, Stephen E.; Weber, Marvin J.

2005-01-01

Lutetium and yttrium borates doped with europium, terbium, gadolinium, etc. have been synthesized by dissolving initial oxides and nitrates in ammonium nitrate melt and thermal decomposition of the solvent. Annealings in the range of 500-1100 deg. C modified the dimensions of the grains from 2 to 3 nm to more than 100 nm. Significant dependence of the structure of lutetium borate on slight doping with rare earth ions has been found: terbium makes high-temperature vaterite phase preferential at room temperature, whereas europium stabilizes low-temperature calcite phase. Influence of the structure of the borates on the pattern of the luminescence spectra of europium dopant was observed. Possibilities for manufacturing of scintillating lutetium borate ceramics by means of this method of synthesis are discussed

Structure and luminescence spectra of lutetium and yttrium borates synthesized from ammonium nitrate melt

Science.gov (United States)

Klassen, Nikolay V.; Shmurak, Semion Z.; Shmyt'ko, Ivan M.; Strukova, Galina K.; Derenzo, Stephen E.; Weber, Marvin J.

2005-01-01

Lutetium and yttrium borates doped with europium, terbium, gadolinium, etc. have been synthesized by dissolving initial oxides and nitrates in ammonium nitrate melt and thermal decomposition of the solvent. Annealings in the range of 500-1100°C modified the dimensions of the grains from 2 to 3 nm to more than 100 nm. Significant dependence of the structure of lutetium borate on slight doping with rare earth ions has been found: terbium makes high-temperature vaterite phase preferential at room temperature, whereas europium stabilizes low-temperature calcite phase. Influence of the structure of the borates on the pattern of the luminescence spectra of europium dopant was observed. Possibilities for manufacturing of scintillating lutetium borate ceramics by means of this method of synthesis are discussed.

Lanthanide tetrakis-β-diketonate dimers for solution-processed OLEDs

Energy Technology Data Exchange (ETDEWEB)

Martins, J.P. [CEMDRX, Physics Department, Universidade de Coimbra, Rua Larga, P-3004-516 Coimbra (Portugal); Serviço de Medicina Nuclear, SESARAM E.P.E., Av. Luís de Camões 57, P-9004-514 Funchal, Madeira (Portugal); Martín-Ramos, P. [Higher Technical School of Telecommunications Engineering, Universidad de Valladolid, Campus Miguel Delibes, Paseo Belén 15, 47011 Valladolid (Spain); Coya, C.; Álvarez, A.L. [Escuela Superior de Ciencias Experimentales y Tecnología (ESCET), Universidad Rey Juan Carlos, 28933 Madrid (Spain); Pereira, L.C. [Solid State Group, UCQR, IST/CTN, Instituto Superior Técnico, UTL, Estrada Nacional 10, km 139.7, 2695-066 Bobadela LRS (Portugal); Díaz, R. [Electrochemical Processes Unit, IMDEA Energy Institute, Avda. Ramón de la Sagra 3, 28935 Móstoles Madrid (Spain); Martín-Gil, J. [Advanced Materials Laboratory, ETSIIAA, Universidad de Valladolid, Avenida de Madrid 44, 34004 Palencia (Spain); Ramos Silva, M., E-mail: manuela@pollux.fis.uc.pt [CEMDRX, Physics Department, Universidade de Coimbra, Rua Larga, P-3004-516 Coimbra (Portugal)

2014-10-15

Two Eu{sup 3+} and Tb{sup 3+} homodinuclear complexes with 1,3-diphenyl-1,3- propanedione have been synthesized and characterized by single crystal X-ray crystallography, vibrational analysis, calorimetric, magnetic and optical studies. The two isostructural complexes consist of two tetrakis units bridged by two potassium ions, thus affording a neutral charge. The photoluminescence measurements reveal that efficient energy transfer from the β-diketonate ligand to the central Ln{sup 3+} ion by antenna effect is achieved for Eu{sup 3+}, leading to intense red emission with an intrinsic quantum yield of 48%. The Eu{sup 3+}-based material has been assessed as the active layer in a solution-processed OLED with glass/ITO/PEDOT:PSS/PVK:Eu-dimer/TiO{sub 2}/Al structure and its electroluminescent properties have been inspected, showing a threshold voltage of 6 V. - Highlights: • Europium and terbium homodinuclear complexes were synthesized and characterized. • Efficient energy transfer from ligands to Eu{sup 3+} is achieved by antenna effect. • Intense red emission with an intrinsic quantum yield of 48% is attained. • Eu{sup 3+} complex has been integrated in a solution-processed OLED as the emissive layer.

Hyperfine interactions measured by nuclear orientation technique

International Nuclear Information System (INIS)

Brenier, R.

1982-01-01

This report concerns the use of hyperfine interaction to magnetism measurements and to the determination of the nuclear structure of Terbium isotopes by the low temperature nuclear orientation technique. In the first part we show that the rhodium atom does not support any localized moment in the chromium matrix. The hyperfine magnetic field at the rhodium nuclear site follows the Overhauser distribution, and the external applied magnetic field supports a negative Knight shift of 16%. In the second part we consider the structure of neutron deficient Terbium isotopes. We introduce a coherent way of evaluation and elaborate a new nuclear thermometer. The magnetic moments allows to strike on the studied states configuration. The analysis of our results shows a decrease of the nuclear deformation for the lighter isotopes [fr

Communication complexity and information complexity

Science.gov (United States)

Pankratov, Denis

Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information

Neutron and X-ray small angle scattering (S.A.S.) study of the amorphous alloy Tbsub(.25)Cusub(.75)

International Nuclear Information System (INIS)

Boucher, B.

1980-07-01

The magnetic properties of amorphous alloys REsub(x) Msub(x-1) (R.E.=heavy rare earths, M=Cu, Ag, Au) have been widely studied. They are of the speromagnetic type for x>=0.33 and are mictomagnetic for x -12 cm). Also the atomic volume of Terbium (approximately 33 A 3 ) is almost three times that of Copper (11.8 A 3 ) and Cu is less absorbant than Ag or Au. Tb alloys exhibit high magnetic ordering temperatures and important moments in contrast to the majority of other alloys of the same family. One inconvenience with Terbium, however, is the large (X-ray) fluorescence (lambda Cu). In order to confirm some interpretations of S.A.S., we were obliged to determine some physical parameters such as the density and porosity and to examine the sample with microscope. These results are also given here

Luminescent properties of Al{sub 2}O{sub 3}: Tb powders; Propiedades luminiscentes de polvos de Al{sub 2}O{sub 3}: Tb

Energy Technology Data Exchange (ETDEWEB)

Esparza G, A.E.; Garcia, M.; Falcony, C.; Azorin N, J. [CICATA-IPN, Legaria 694, Col. Irrigacion, 11500 Mexico D.F. (Mexico)

2000-07-01

In this work the photo luminescent and cathode luminescent characteristics of aluminium oxide (Al{sub 2}O{sub 3}) powders impurified with terbium (Tb) were studied for their use in dosimetry. The optical, structural, morphological characteristics of the powders as function of variation in the impurity concentration and the annealing temperature will be presented. As regards the optical properties of powders (photoluminescence and cathode luminescence) it was observed a characteristic emission associated with radiative transitions between electron energy levels of terbium, the spectra associated with this emission consists of several peaks associated with such transitions. In the structural and morphological characterization (X-ray diffraction and scanning electron microscopy) it was appreciated that in accordance the annealing temperature of powders is augmented it is evident the apparition of certain crystalline phases. The results show that this is a promissory material for radiation dosimetry. (Author)

Luminescent properties of Al2O3: Tb powders

International Nuclear Information System (INIS)

Esparza G, A.E.; Garcia, M.; Falcony, C.; Azorin N, J.

2000-01-01

In this work the photo luminescent and cathode luminescent characteristics of aluminium oxide (Al 2 O 3 ) powders impurified with terbium (Tb) were studied for their use in dosimetry. The optical, structural, morphological characteristics of the powders as function of variation in the impurity concentration and the annealing temperature will be presented. As regards the optical properties of powders (photoluminescence and cathode luminescence) it was observed a characteristic emission associated with radiative transitions between electron energy levels of terbium, the spectra associated with this emission consists of several peaks associated with such transitions. In the structural and morphological characterization (X-ray diffraction and scanning electron microscopy) it was appreciated that in accordance the annealing temperature of powders is augmented it is evident the apparition of certain crystalline phases. The results show that this is a promissory material for radiation dosimetry. (Author)

Are LOD and LOQ Reliable Parameters for Sensitivity Evaluation of Spectroscopic Methods?

Science.gov (United States)

Ershadi, Saba; Shayanfar, Ali

2018-03-22

The limit of detection (LOD) and the limit of quantification (LOQ) are common parameters to assess the sensitivity of analytical methods. In this study, the LOD and LOQ of previously reported terbium sensitized analysis methods were calculated by different methods, and the results were compared with sensitivity parameters [lower limit of quantification (LLOQ)] of U.S. Food and Drug Administration guidelines. The details of the calibration curve and standard deviation of blank samples of three different terbium-sensitized luminescence methods for the quantification of mycophenolic acid, enrofloxacin, and silibinin were used for the calculation of LOD and LOQ. A comparison of LOD and LOQ values calculated by various methods and LLOQ shows a considerable difference. The significant difference of the calculated LOD and LOQ with various methods and LLOQ should be considered in the sensitivity evaluation of spectroscopic methods.

On possibility of transuranium element by the method of transport reactions

International Nuclear Information System (INIS)

Sinitsyna, G.S.; Krashenitsyn, G.N.; Shestakov, B.I.

1983-01-01

A possibility to use chemical transport reaction for separation of uranium, plutonium and some transplutonium elements is shown. The method is based on the use of the known plutonium property to form tetrachloride existing only in the gaseous phase in chlorine atmosphere, which is transported ever the temperature gradiept. Two ways of transport reaction realization - the method of flow and the method of diffusion in closed volume are tested. The experiments are made using specially synthesized plutonium dioxide, containing uranium, americium, curium, lanthanum, terbium, barium. Chlorination is realized by the mixture of chlorine and carbon tetrachloride at temperatures 723-953 K. Plutonium trichloride is deposited in the range 613-653 K, uranium - in the range 473-523 K, curium, americium, lanthanum, terbium, barium remain in the start zone if its temperature does not exceed 873 K

Radio-luminescence efficiency and rare-earth dispersion in Tb-doped silica glasses

Czech Academy of Sciences Publication Activity Database

Fasoli, M.; Moretti, F.; Lauria, A.; Chiodini, N.; Vedda, A.; Nikl, Martin

2007-01-01

Roč. 42, - (2007), s. 784-787 ISSN 1350-4487 Institutional research plan: CEZ:AV0Z10100521 Keywords : sol-gel * scintillators * silica * rare earths * terbium Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.054, year: 2007

Performance of 20 Ci 137Cs γ-ray Compton spectrometer for the ...

Indian Academy of Sciences (India)

of the machine is assessed using aluminum, terbium and mercury samples and the exper- imental data from ... keV) are used. This is particularly true in the case of heavy elements ... In this paper, a design with optimum choice of experimental.

The temperature dependence of thermooptical properties of magnetooptical TAG ceramics doped with silicon and titanium

Science.gov (United States)

Starobor, Aleksey; Palashov, Oleg

2018-04-01

Thermal effects in terbium aluminum garnet (TAG) ceramics (thermal lens and thermally induced depolarization) doped with silicon and titanium were investigated in temperature range of 79-293K. Samples with low dopant concentrations shows decreasing of negative thermal effects with cooling to 79 K. However for most part of samples thermal depolarization starts increasing after initial decreasing with cooling. Apparently it is connected with defects in media. Best sample (0.4 at% of Si) as pure TAG shows monotonous decreasing of thermally induced depolarization and 3.5 times Verdet constant increasing with cooling to 79 K, that leads to 1.8-times advantage over common magnetooptical media - terbium gallium garnet. It allows to provide an isolation of 30 dB at a radiation power of more than 6 kW as estimated. However, the procedure for creating ceramics samples obviously needs improvement because of the large scatter in the quality of the samples.

Cerium fluoride nanoparticles protect cells against oxidative stress

International Nuclear Information System (INIS)

Shcherbakov, Alexander B.; Zholobak, Nadezhda M.; Baranchikov, Alexander E.; Ryabova, Anastasia V.; Ivanov, Vladimir K.

2015-01-01

A novel facile method of non-doped and fluorescent terbium-doped cerium fluoride stable aqueous sols synthesis is proposed. Intense green luminescence of CeF 3 :Tb nanoparticles can be used to visualize these nanoparticles' accumulation in cells using confocal laser scanning microscopy. Cerium fluoride nanoparticles are shown for the first time to protect both organic molecules and living cells from the oxidative action of hydrogen peroxide. Both non-doped and terbium-doped CeF 3 nanoparticles are shown to provide noteworthy protection to cells against the vesicular stomatitis virus. - Highlights: • Facile method of CeF 3 and CeF 3 :Tb stable aqueous sols synthesis is proposed. • Naked CeF 3 nanoparticles are shown to be non-toxic and to protect cells from the action of H 2 O 2 . • CeF 3 and CeF 3 :Tb nanoparticles are shown to protect living cells against the vesicular stomatitis virus

The use of rare earth radiotracers in the study of solvent extraction kinetics

International Nuclear Information System (INIS)

Lim, T.M.; Tran, T.

1993-01-01

The suitability of rare earth radionuclides as tracers in research and industry are assessed. In general, the most desirable characteristics of radiotracers for process studies are a half-life in the range 5-200 days, a high yield, high energy γ-emission and low cost of production. The majority of rare earths have at least one radionuclide with acceptable characteristics. The application of radiotracers to the study of kinetics of rare earth solvent extraction have been studied using a modified Lewis cell. Terbium-160 was selected as the most suitable rare earth radionuclide for our experiments. Samples of both aqueous and organic phases were continuous withdrawn, monitored using an automated γ-counting system based on two sodium iodide detectors and then pumped back to the Lewis cell. Excellent results were obtained and the rate of extraction was shown to be first order with respect to the terbium concentration. 6 refs., 1 tab., 7 figs

Lyoluminescence sensitisation

International Nuclear Information System (INIS)

Galand, E.; Niezette, J.; Vanderschueren, J.

1993-01-01

Lyoluminescence (LL) of several carbohydrates and amino acids has been measured in water for a γ dose of respectively, 20 Gy and 50 Gy. It has been demonstrated that the LL yield depends markedly not only on the nature of the LL material but also on its commercial origin. By using solutions of organic dyes such as eosin B, rhodamine B or fluorescein, a substantial enhancement of LL has been observed with carbohydrates. Concentration effect has been investigated and maximum LL yields have been observed in the range 10 -5 -10 -4 mol. On the other hand, LL of amino acids has been increased by the use of rare earth ion solutions. Dysprosium, europium and terbium solutions have been used, but it has been proved that terbium nitrate is the most appropriate solution. Concentration effect has been studied for several amino acids and dosimetric response of glutamine has been investigated with different rare earth ions solutions. (Author)

Cerium fluoride nanoparticles protect cells against oxidative stress

Energy Technology Data Exchange (ETDEWEB)

Shcherbakov, Alexander B.; Zholobak, Nadezhda M. [Zabolotny Institute of Microbiology and Virology, National Academy of Sciences of Ukraine, Kyiv D0368 (Ukraine); Baranchikov, Alexander E. [Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991 (Russian Federation); Ryabova, Anastasia V. [Prokhorov General Physics Institute of the Russian Academy of Sciences, Moscow 119991 (Russian Federation); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow 115409 (Russian Federation); Ivanov, Vladimir K., E-mail: van@igic.ras.ru [Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991 (Russian Federation); National Research Tomsk State University, Tomsk 634050 (Russian Federation)

2015-05-01

A novel facile method of non-doped and fluorescent terbium-doped cerium fluoride stable aqueous sols synthesis is proposed. Intense green luminescence of CeF{sub 3}:Tb nanoparticles can be used to visualize these nanoparticles' accumulation in cells using confocal laser scanning microscopy. Cerium fluoride nanoparticles are shown for the first time to protect both organic molecules and living cells from the oxidative action of hydrogen peroxide. Both non-doped and terbium-doped CeF{sub 3} nanoparticles are shown to provide noteworthy protection to cells against the vesicular stomatitis virus. - Highlights: • Facile method of CeF{sub 3} and CeF{sub 3}:Tb stable aqueous sols synthesis is proposed. • Naked CeF{sub 3} nanoparticles are shown to be non-toxic and to protect cells from the action of H{sub 2}O{sub 2}. • CeF{sub 3} and CeF{sub 3}:Tb nanoparticles are shown to protect living cells against the vesicular stomatitis virus.

Detection of protease activity by fluorescent protein FRET sensors: from computer simulation to live cells

Science.gov (United States)

Goryashchenko, Alexander S.; Khrenova, Maria G.; Savitsky, Alexander P.

2018-04-01

Förster resonance energy transfer (FRET) sensors are widely used for the detection of protease activity in vitro and in vivo. Usually they consist of a FRET pair connected with a polypeptide linker containing a specific cleavage site for the relevant protease. Use of the fluorescent proteins as components of the FRET pair allows genetic encoding of such sensors and solves the problem of their delivery into live cells and animals. There are several ways to improve the properties of such sensors, mainly to increase FRET efficiency and therefore the dynamic range. One of the ways to achieve this is to use a non-fluorescent chromoprotein as an acceptor. Molecular dynamic simulations may assist in the construction of linker structures connecting donor and acceptor molecules. Estimation of the orientation factor κ 2 can be obtained by methods based on quantum theory and combined quantum mechanics/molecular mechanics approaches. The linker can be structured by hydrophobic interactions, bringing it into a closed conformation that shortens the distance between donor and acceptor and, consequently, increases FRET efficiency. We analyzed the effects of different linker structures on the detection of caspase-3 activity using a non-fluorescent acceptor. Also we have constructed the Tb3+- TagRFP sensor in which a complex of the terbium ion and terbium-binding peptide is used as a donor. This allowed us to use the unique property of lanthanide ions—fluorescence lifetime up to milliseconds—to perform measurements with time delay and exclude the nanosecond-order fluorescence. Using our systems as a starting point, by changing the recognition site in the linker it is possible to perform imaging of different protease activity in vitro or in vivo.

Tuning the activity of Pt alloy electrocatalysts by means of the lanthanide contraction

DEFF Research Database (Denmark)

Escribano, Maria Escudero; Malacrida, Paolo; Hansen, Martin Hangaard

2016-01-01

is lanthanum, cerium, samarium, gadolinium, terbium, dysprosium, thulium, or calcium. The materials are among the most active polycrystalline Pt-based catalysts reported, presenting activity enhancement by a factor of 3 to 6 over Pt. The active phase consists of a Pt overlayer formed by acid leaching. The ORR...

Spin-glass transition in disordered terbium

International Nuclear Information System (INIS)

Hauser, J.J.

1985-01-01

While crystalline Tb is a helix antiferromagnet with a Neel temperature of 229 K which becomes ferromagnetic at 222 K, disordered Tb exhibits a spin-glass transition. The spin-glass freezing temperature ranges from 183 to 53 K, the lowest temperatures corresponding to the greatest degree of atomic disorder. These experiments constitute the first evidence for an elemental spin-glass. (author)

Spectroscopic analysis of lithium terbium tetrafluoride

DEFF Research Database (Denmark)

Christensen, H.P.

1978-01-01

The absorption spectra of Tb3+ in LiTbF4 have been recorded in the spectral interval from 4000 to 25000 cm-1 and for temperatures between 2.3 and 150 K. This covers the transitions from the ground multiplet 7F6 to the multiplets 7F3, 7F2, 7F1, 7F0, and 5D4. The transitions were predominantly of e...

Lanthanide-based laser-induced phosphorescence for spray diagnostics

Energy Technology Data Exchange (ETDEWEB)

Voort, D. D. van der, E-mail: d.d.v.d.voort@tue.nl; Water, W. van de; Kunnen, R. P. J.; Clercx, H. J. H.; Heijst, G. J. F. van [Applied Physics Department, Eindhoven University of Technology, 5612 AZ Eindhoven (Netherlands); Maes, N. C. J.; Sweep, A. M.; Dam, N. J. [Mechanical Engineering Department, Eindhoven University of Technology, 5612 AZ Eindhoven (Netherlands); Lamberts, T. [Institute of Theoretical Chemistry, University of Stuttgart, D-70569 Stuttgart (Germany)

2016-03-15

Laser-induced phosphorescence (LIP) is a relatively recent and versatile development for studying flow dynamics. This work investigates certain lanthanide-based molecular complexes for their use in LIP for high-speed sprays. Lanthanide complexes in solutions have been shown to possess long phosphorescence lifetimes (∼1-2 ms) and to emit light in the visible wavelength range. In particular, europium and terbium complexes are investigated using fluorescence/phosphorescence spectrometry, showing that europium-thenoyltrifluoracetone-trioctylphosphineoxide (Eu-TTA-TOPO) can be easily and efficiently excited using a standard frequency-tripled Nd:YAG laser. The emitted spectrum, with maximum intensity at a wavelength of 614 nm, is shown not to vary strongly with temperature (293-383 K). The decay constant of the phosphorescence, while independent of ambient pressure, decreases by approximately 12 μs/K between 323 and 373 K, with the base level of the decay constant dependent on the used solvent. The complex does not luminesce in the gas or solid state, meaning only the liquid phase is visualized, even in an evaporating spray. By using an internally excited spray containing the phosphorescent complex, the effect of vaporization is shown through the decrease in measured intensity over the length of the spray, together with droplet size measurements using interferometric particle imaging. This study shows that LIP, using the Eu-TTA-TOPO complex, can be used with different solvents, including diesel surrogates. Furthermore, it can be easily handled and used in sprays to investigate spray breakup and evaporation.

Untitled

Indian Academy of Sciences (India)

Recently there has been a spurt in studies on heavy rare earth metals because of the magnon-phonon interactions observed in them. The phonon dispersion relations in terbium have been investigated by Houmann and Nicklow (1970) and by Menon and. Rao (1972). The magnon dispersion relations have been measured ...

Rare earth oxyhalogenide base thermoluminescent material

International Nuclear Information System (INIS)

Rabatin, J.G.

1976-01-01

A process is described that consists to expose a thermoluminescent material to ionizing radiations, the material being a rare earth oxyhalogenide with terbium additions, to heat this material up to the emission of visible radiations and to measure the emitted radiations which are proportional to the ionizing radiation dose [fr

Complex chemistry

International Nuclear Information System (INIS)

Kim, Bong Gon; Kim, Jae Sang; Kim, Jin Eun; Lee, Boo Yeon

2006-06-01

This book introduces complex chemistry with ten chapters, which include development of complex chemistry on history coordination theory and Warner's coordination theory and new development of complex chemistry, nomenclature on complex with conception and define, chemical formula on coordination compound, symbol of stereochemistry, stereo structure and isomerism, electron structure and bond theory on complex, structure of complex like NMR and XAFS, balance and reaction on solution, an organo-metallic chemistry, biology inorganic chemistry, material chemistry of complex, design of complex and calculation chemistry.

Viscosity measurements of molten refractory metals using an electrostatic levitator

International Nuclear Information System (INIS)

Ishikawa, Takehiko; Paradis, Paul-François; Okada, Junpei T; Watanabe, Yuki

2012-01-01

Viscosities of several refractory metals (titanium, nickel, zirconium, niobium, ruthenium, rhodium, hafnium, iridium and platinum) and terbium have been measured by the oscillation drop method with an improved procedure. The measured data were less scattered than our previous measurements. Viscosities at their melting temperatures showed good agreement with literature values and some predicted values. (paper)

Structural Characterization and Absolute Luminescence Efficiency Evaluation of Gd2O2S High Packing Density Ceramic Screens Doped with Tb3+ and Eu3+ for further Applications in Radiology

Science.gov (United States)

Dezi, Anna; Monachesi, Elenasophie; D'Ignazio, Michela; Scalise, Lorenzo; Montalto, Luigi; Paone, Nicola; Rinaldi, Daniele; Mengucci, Paolo; Loudos, George; Bakas, Athanasios; Michail, Christos; Valais, Ioannis; Fountzoula, Christine; Fountos, George; David, Stratos

2017-11-01

Rare earth activators are impurities added in the phosphor material to enhance probability of visible photon emission during the luminescence process. The main activators employed are rare earth trivalent ions such as Ce+3, Tb+3, Pr3+ and Eu+3. In this work, four terbium-activated Gd2O2S (GOS) powder screens with different thicknesses (1049 mg/cm2, 425.41 mg/cm2, 313 mg/cm2 and 187.36 mg/cm2) and one europium-activated GOS powder screen (232.18 mg/cm2) were studied to investigate possible applications for general radiology detectors. Results presented relevant differences in crystallinity between the GOS:Tb doped screens and GOS:Eu screens in respect to the dopant agent present. The AE (Absolute efficiency) was found to rise (i) with the increase of the X-ray tube voltage with the highest peaking at 110kVp and (ii) with the decrease of the thickness among the four GOS:Tb. Comparing similar thickness values, the europium-activated powder screen showed lower AE than the corresponding terbium-activated.

Magnetic measurements of the transuranium elements. Progress report, January 1, 1984-December 31, 1984

International Nuclear Information System (INIS)

Huray, P.G.; Nave, S.E.

1984-01-01

Measurements of the magnetic properties of dhcp californium-249 metal indicated the presence of three regions of differing magnetic character. Additional measurements are also reported. Magnetic moments and valence states of terbium in TbF 3 , BaTbO 3 , and TbO 1 8 are discussed. Progress on high-field operation of the micro-magnetic susceptometer is reported

Charge Carrier Trapping Processes in RE2O2S (RE = La, Gd, Y, and Lu)

NARCIS (Netherlands)

Luo, H.; Bos, A.J.J.; Dorenbos, P.

2017-01-01

Two different charge carrier trapping processes have been investigated in RE2O2S:Ln3+ (RE = La, Gd, Y, and Lu; Ln = Ce, Pr, and Tb) and RE2O2S:M (M = Ti4+ and Eu3+). Cerium, praseodymium and terbium act as recombination centers and hole trapping centers while host intrinsic defects provide the

ComplexViewer: visualization of curated macromolecular complexes.

Science.gov (United States)

Combe, Colin W; Sivade, Marine Dumousseau; Hermjakob, Henning; Heimbach, Joshua; Meldal, Birgit H M; Micklem, Gos; Orchard, Sandra; Rappsilber, Juri

2017-11-15

Proteins frequently function as parts of complexes, assemblages of multiple proteins and other biomolecules, yet network visualizations usually only show proteins as parts of binary interactions. ComplexViewer visualizes interactions with more than two participants and thereby avoids the need to first expand these into multiple binary interactions. Furthermore, if binding regions between molecules are known then these can be displayed in the context of the larger complex. freely available under Apache version 2 license; EMBL-EBI Complex Portal: http://www.ebi.ac.uk/complexportal; Source code: https://github.com/MICommunity/ComplexViewer; Package: https://www.npmjs.com/package/complexviewer; http://biojs.io/d/complexviewer. Language: JavaScript; Web technology: Scalable Vector Graphics; Libraries: D3.js. colin.combe@ed.ac.uk or juri.rappsilber@ed.ac.uk. © The Author 2017. Published by Oxford University Press.

Synchronization in node of complex networks consist of complex chaotic system

Energy Technology Data Exchange (ETDEWEB)

Wei, Qiang, E-mail: qiangweibeihua@163.com [Beihua University computer and technology College, BeiHua University, Jilin, 132021, Jilin (China); Digital Images Processing Institute of Beihua University, BeiHua University, Jilin, 132011, Jilin (China); Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, 116024 (China); Xie, Cheng-jun [Beihua University computer and technology College, BeiHua University, Jilin, 132021, Jilin (China); Digital Images Processing Institute of Beihua University, BeiHua University, Jilin, 132011, Jilin (China); Liu, Hong-jun [School of Information Engineering, Weifang Vocational College, Weifang, 261041 (China); Li, Yan-hui [The Library, Weifang Vocational College, Weifang, 261041 (China)

2014-07-15

A new synchronization method is investigated for node of complex networks consists of complex chaotic system. When complex networks realize synchronization, different component of complex state variable synchronize up to different scaling complex function by a designed complex feedback controller. This paper change synchronization scaling function from real field to complex field for synchronization in node of complex networks with complex chaotic system. Synchronization in constant delay and time-varying coupling delay complex networks are investigated, respectively. Numerical simulations are provided to show the effectiveness of the proposed method.

Generalized Combination Complex Synchronization for Fractional-Order Chaotic Complex Systems

Directory of Open Access Journals (Sweden)

Cuimei Jiang

2015-07-01

Full Text Available Based on two fractional-order chaotic complex drive systems and one fractional-order chaotic complex response system with different dimensions, we propose generalized combination complex synchronization. In this new synchronization scheme, there are two complex scaling matrices that are non-square matrices. On the basis of the stability theory of fractional-order linear systems, we design a general controller via active control. Additionally, by virtue of two complex scaling matrices, generalized combination complex synchronization between fractional-order chaotic complex systems and real systems is investigated. Finally, three typical examples are given to demonstrate the effectiveness and feasibility of the schemes.

Complexity explained

CERN Document Server

Erdi, Peter

2008-01-01

This book explains why complex systems research is important in understanding the structure, function and dynamics of complex natural and social phenomena. Readers will learn the basic concepts and methods of complex system research.

Coherent magnetic structures in terbium/holmium superlattices

DEFF Research Database (Denmark)

Bryn-Jacobsen, C.; Cowley, R.A.; McMorrow, D.F.

1997-01-01

to 230 K, two samples retain this magnetic structure while the third undergoes a transition first to a mixed phase of helically and ferromagnetically ordered Tb moments, then to a phase with only helically ordered To moments. Ln all cases, the magnetic ordering is found to be long ranged, with coherence...

Magnon energies and exchange interactions in terbium

DEFF Research Database (Denmark)

Houmann, Jens Christian Gylden

1968-01-01

The magnon density of states, and hence the magnetic contribution to the specific heat, and also the exchange interaction between ions in the same sublattice have been calculated for Tb at 90°K, using experimental results obtained by inelastic neutron scattering.......The magnon density of states, and hence the magnetic contribution to the specific heat, and also the exchange interaction between ions in the same sublattice have been calculated for Tb at 90°K, using experimental results obtained by inelastic neutron scattering....

Magnon lifetimes in terbium at low temperatures

International Nuclear Information System (INIS)

Bjerrum Moeller, H.; Mackintosh, A.R.

1979-01-01

The lifetimes of magnons propagating in the c-direction of Tb at 4.2 K have been measured by inelastic neutron scattering. In contrast to the behaviour at higher temperatures, where magnon-magnon scattering predominates, the broadening of the magnons increases towards the boundary of the single Brillouin zone, both in the acoustic and optical branches. This suggests that the scattering of the magnons by conduction electrons is important, and the observed lifetimes are consistent with a recent estimate of the magnitude of this effect. The acoustic magnons of very long wavelength behave anomalously, presumably due to dipolar interactions

Test plan for air monitoring during the Cryogenic Retrieval Demonstration

International Nuclear Information System (INIS)

Yokuda, E.

1992-06-01

This report presents a test plan for air monitoring during the Cryogenic Retrieval Demonstration (CRD). Air monitors will be used to sample for the tracer elements neodymium, terbium, and ytterbium, and dysprosium. The results from this air monitoring will be used to determine if the CRD is successful in controlling dust and minimizing contamination. Procedures and equipment specifications for the test are included

Thermoluminescent coactivated rare earth oxyhalide phosphors and x-ray image converters utilizing said phosphors

International Nuclear Information System (INIS)

Rabatin, J.G.

1984-01-01

Oxyhalides of lanthanum, gadolinium and lutetium coactivated with a first activator selected from bismuth and samarium to provide the color of light emission and a second coactivator (e.g. terbium or praseodymium) which increases the amount of stored energy in a stored radiographic latent image are found to be superior in their conversion efficiency of x-rays to visible light. (author)

On Measuring the Complexity of Networks: Kolmogorov Complexity versus Entropy

Directory of Open Access Journals (Sweden)

Mikołaj Morzy

2017-01-01

Full Text Available One of the most popular methods of estimating the complexity of networks is to measure the entropy of network invariants, such as adjacency matrices or degree sequences. Unfortunately, entropy and all entropy-based information-theoretic measures have several vulnerabilities. These measures neither are independent of a particular representation of the network nor can capture the properties of the generative process, which produces the network. Instead, we advocate the use of the algorithmic entropy as the basis for complexity definition for networks. Algorithmic entropy (also known as Kolmogorov complexity or K-complexity for short evaluates the complexity of the description required for a lossless recreation of the network. This measure is not affected by a particular choice of network features and it does not depend on the method of network representation. We perform experiments on Shannon entropy and K-complexity for gradually evolving networks. The results of these experiments point to K-complexity as the more robust and reliable measure of network complexity. The original contribution of the paper includes the introduction of several new entropy-deceiving networks and the empirical comparison of entropy and K-complexity as fundamental quantities for constructing complexity measures for networks.

Complex dynamical invariants for two-dimensional complex potentials

Indian Academy of Sciences (India)

Abstract. Complex dynamical invariants are searched out for two-dimensional complex poten- tials using rationalization method within the framework of an extended complex phase space characterized by x = x1 + ip3, y = x2 + ip4, px = p1 + ix3, py = p2 + ix4. It is found that the cubic oscillator and shifted harmonic oscillator ...

Complex Fuzzy Set-Valued Complex Fuzzy Measures and Their Properties

Science.gov (United States)

Ma, Shengquan; Li, Shenggang

2014-01-01

Let F*(K) be the set of all fuzzy complex numbers. In this paper some classical and measure-theoretical notions are extended to the case of complex fuzzy sets. They are fuzzy complex number-valued distance on F*(K), fuzzy complex number-valued measure on F*(K), and some related notions, such as null-additivity, pseudo-null-additivity, null-subtraction, pseudo-null-subtraction, autocontionuous from above, autocontionuous from below, and autocontinuity of the defined fuzzy complex number-valued measures. Properties of fuzzy complex number-valued measures are studied in detail. PMID:25093202

The complex portal--an encyclopaedia of macromolecular complexes.

Science.gov (United States)

Meldal, Birgit H M; Forner-Martinez, Oscar; Costanzo, Maria C; Dana, Jose; Demeter, Janos; Dumousseau, Marine; Dwight, Selina S; Gaulton, Anna; Licata, Luana; Melidoni, Anna N; Ricard-Blum, Sylvie; Roechert, Bernd; Skyzypek, Marek S; Tiwari, Manu; Velankar, Sameer; Wong, Edith D; Hermjakob, Henning; Orchard, Sandra

2015-01-01

The IntAct molecular interaction database has created a new, free, open-source, manually curated resource, the Complex Portal (www.ebi.ac.uk/intact/complex), through which protein complexes from major model organisms are being collated and made available for search, viewing and download. It has been built in close collaboration with other bioinformatics services and populated with data from ChEMBL, MatrixDB, PDBe, Reactome and UniProtKB. Each entry contains information about the participating molecules (including small molecules and nucleic acids), their stoichiometry, topology and structural assembly. Complexes are annotated with details about their function, properties and complex-specific Gene Ontology (GO) terms. Consistent nomenclature is used throughout the resource with systematic names, recommended names and a list of synonyms all provided. The use of the Evidence Code Ontology allows us to indicate for which entries direct experimental evidence is available or if the complex has been inferred based on homology or orthology. The data are searchable using standard identifiers, such as UniProt, ChEBI and GO IDs, protein, gene and complex names or synonyms. This reference resource will be maintained and grow to encompass an increasing number of organisms. Input from groups and individuals with specific areas of expertise is welcome. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Complexity Plots

KAUST Repository

Thiyagalingam, Jeyarajan

2013-06-01

In this paper, we present a novel visualization technique for assisting the observation and analysis of algorithmic complexity. In comparison with conventional line graphs, this new technique is not sensitive to the units of measurement, allowing multivariate data series of different physical qualities (e.g., time, space and energy) to be juxtaposed together conveniently and consistently. It supports multivariate visualization as well as uncertainty visualization. It enables users to focus on algorithm categorization by complexity classes, while reducing visual impact caused by constants and algorithmic components that are insignificant to complexity analysis. It provides an effective means for observing the algorithmic complexity of programs with a mixture of algorithms and black-box software through visualization. Through two case studies, we demonstrate the effectiveness of complexity plots in complexity analysis in research, education and application. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and Blackwell Publishing Ltd.

Complex differential geometry

CERN Document Server

Zheng, Fangyang

2002-01-01

The theory of complex manifolds overlaps with several branches of mathematics, including differential geometry, algebraic geometry, several complex variables, global analysis, topology, algebraic number theory, and mathematical physics. Complex manifolds provide a rich class of geometric objects, for example the (common) zero locus of any generic set of complex polynomials is always a complex manifold. Yet complex manifolds behave differently than generic smooth manifolds; they are more coherent and fragile. The rich yet restrictive character of complex manifolds makes them a special and interesting object of study. This book is a self-contained graduate textbook that discusses the differential geometric aspects of complex manifolds. The first part contains standard materials from general topology, differentiable manifolds, and basic Riemannian geometry. The second part discusses complex manifolds and analytic varieties, sheaves and holomorphic vector bundles, and gives a brief account of the surface classifi...

(II) complexes

African Journals Online (AJOL)

activities of Schiff base tin (II) complexes. Neelofar1 ... Conclusion: All synthesized Schiff bases and their Tin (II) complexes showed high antimicrobial and ...... Singh HL. Synthesis and characterization of tin (II) complexes of fluorinated Schiff bases derived from amino acids. Spectrochim Acta Part A: Molec Biomolec.

Synthesis and characterization of Tin / Titanium mixed oxide nanoparticles doped with lanthanide for biomarking

International Nuclear Information System (INIS)

Paganini, Paula Pinheiro

2012-01-01

This work presents the synthesis, characterization and photo luminescent study of tin and titanium mixed oxide nanoparticles doped with europium, terbium and neodymium to be used with luminescent markers on biological systems. The syntheses were done by co-precipitation, protein sol-gel and Pechini methods and the nanoparticles were characterized by infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, X-ray diffraction and X-ray absorption spectroscopy. The photo luminescent properties studies were conducted for luminophores doped with europium, terbium and neodymium synthesized by coprecipitation method. For luminophore doped with europium it was possible to calculate the intensity parameters and quantum yield and it showed satisfactory results. In the case of biological system marking it was necessary the functionalization of these particles to allow them to bind to the biological part to be studied. So the nanoparticles were functionalized by microwave and Stöber methods and characterized by infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction obtaining qualitative response of functionalization efficacy. The ninhydrin spectroscopic method was used for quantification of luminophores functionalization. The photo luminescent studies of functionalized particles demonstrate the potential applying of these luminophores as luminescent markers. (author)

Fabrication of Tb3Al5O12 transparent ceramics using co-precipitated nanopowders

Science.gov (United States)

Dai, Jiawei; Pan, Yubai; Wang, Wei; Luo, Wei; Xie, Tengfei; Kou, Huamin; Li, Jiang

2017-11-01

Terbium aluminum garnet (TAG) precursor was synthesized by a co-precipitation method from a mixed solution of terbium and aluminum nitrates using ammonium hydrogen carbonate (AHC) as the precipitant. The powders calcined at different temperatures were investigated by XRD, FTIR and FESEM in order to choose the optimal calcination temperature. Fine and low-agglomerated TAG powders with average particle size of 88 nm were obtained by calcining the precursor at 1100 °C for 4 h. Using this powder as starting material, TAG transparent ceramics were fabricated by vacuum sintering combined with hot isostatic pressing (HIP) sintering. For the sample pre-sintered at 1700 °C for 20 h with HIP post-treated at 1700 °C for 3 h, the average grain size is about 3.9 μm and the in-line transmittance is beyond 55% in the region of 500-1600 nm, reaching a maximum transmittance of 64.2% at the wavelength of 1450 nm. The Verdet constant at 633 nm is measured to be -178.9 rad T-1 m-1, which is 33% larger than that of the commercial TGG single crystal (-134 rad T-1 m-1).

Synthesis and characterization of Tin / Titanium mixed oxide nanoparticles doped with lanthanide for biomarking; Sintese e caracterizacao de nanoparticulas de oxido misto de estanho/titanio dopadas com lantanideos para marcacao biologica

Energy Technology Data Exchange (ETDEWEB)

Paganini, Paula Pinheiro

2012-07-01

This work presents the synthesis, characterization and photo luminescent study of tin and titanium mixed oxide nanoparticles doped with europium, terbium and neodymium to be used with luminescent markers on biological systems. The syntheses were done by co-precipitation, protein sol-gel and Pechini methods and the nanoparticles were characterized by infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, X-ray diffraction and X-ray absorption spectroscopy. The photo luminescent properties studies were conducted for luminophores doped with europium, terbium and neodymium synthesized by coprecipitation method. For luminophore doped with europium it was possible to calculate the intensity parameters and quantum yield and it showed satisfactory results. In the case of biological system marking it was necessary the functionalization of these particles to allow them to bind to the biological part to be studied. So the nanoparticles were functionalized by microwave and Stoeber methods and characterized by infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction obtaining qualitative response of functionalization efficacy. The ninhydrin spectroscopic method was used for quantification of luminophores functionalization. The photo luminescent studies of functionalized particles demonstrate the potential applying of these luminophores as luminescent markers. (author)

Workshop on Recommendation in Complex Scenarios (ComplexRec 2017)

DEFF Research Database (Denmark)

Bogers, Toine; Koolen, Marijn; Mobasher, Bamshad

2017-01-01

Recommendation algorithms for ratings prediction and item ranking have steadily matured during the past decade. However, these state-of-the-art algorithms are typically applied in relatively straightforward scenarios. In reality, recommendation is often a more complex problem: it is usually just...... a single step in the user's more complex background need. These background needs can often place a variety of constraints on which recommendations are interesting to the user and when they are appropriate. However, relatively little research has been done on these complex recommendation scenarios....... The ComplexRec 2017 workshop addressed this by providing an interactive venue for discussing approaches to recommendation in complex scenarios that have no simple one-size-fits-all-solution....

Dynamic complexity: plant receptor complexes at the plasma membrane.

Science.gov (United States)

Burkart, Rebecca C; Stahl, Yvonne

2017-12-01

Plant receptor complexes at the cell surface perceive many different external and internal signalling molecules and relay these signals into the cell to regulate development, growth and immunity. Recent progress in the analyses of receptor complexes using different live cell imaging approaches have shown that receptor complex formation and composition are dynamic and take place at specific microdomains at the plasma membrane. In this review we focus on three prominent examples of Arabidopsis thaliana receptor complexes and how their dynamic spatio-temporal distribution at the PM has been studied recently. We will elaborate on the newly emerging concept of plasma membrane microdomains as potential hubs for specific receptor complex assembly and signalling outputs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Luminescence and energy transfer processes in (Lu,Tb).sub.3./sub.Al.sub.5./sub.O.sub.12./sub. single crystalline films doped with Ce.sup.3+./sup.

Czech Academy of Sciences Publication Activity Database

Bartosiewicz, Karol; Babin, Vladimir; Nikl, Martin; Mareš, Jiří A.; Zorenko, Yu.; Gorbenko, V.

2016-01-01

Roč. 173, May (2016), s. 141-148 ISSN 0022-2313 R&D Projects: GA ČR GA16-15569S; GA ČR GAP204/12/0805 EU Projects: European Commission(XE) 316906 - LUMINET Institutional support: RVO:68378271 Keywords : lutetium terbium aluminum garnets * Ce 3+ * energy transfer * luminescence * single crystalline films Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.686, year: 2016

Preparation of thermoluminescent materials

International Nuclear Information System (INIS)

1976-01-01

Thermoluminescent materials have been found to be suitable for measuring long term exposures to low level ionizing radiation. Oxyhalides of lanthanum, gadolinium and yttrium, including the oxychlorides and oxybromides are activated with terbium and have been found to be most efficient oxygendominated phosphors having thermoradiant efficiencies with excitation by low level ionizing radiation. Thermoluminescence response increases when the previous materials have hafnium and zirconium additives

Revitalizing Complex Analysis: A Transition-to-Proof Course Centered on Complex Topics

Science.gov (United States)

Sachs, Robert

2017-01-01

A new transition course centered on complex topics would help in revitalizing complex analysis in two ways: first, provide early exposure to complex functions, sparking greater interest in the complex analysis course; second, create extra time in the complex analysis course by eliminating the "complex precalculus" part of the course. In…

3D complex: a structural classification of protein complexes.

Directory of Open Access Journals (Sweden)

Emmanuel D Levy

2006-11-01

Full Text Available Most of the proteins in a cell assemble into complexes to carry out their function. It is therefore crucial to understand the physicochemical properties as well as the evolution of interactions between proteins. The Protein Data Bank represents an important source of information for such studies, because more than half of the structures are homo- or heteromeric protein complexes. Here we propose the first hierarchical classification of whole protein complexes of known 3-D structure, based on representing their fundamental structural features as a graph. This classification provides the first overview of all the complexes in the Protein Data Bank and allows nonredundant sets to be derived at different levels of detail. This reveals that between one-half and two-thirds of known structures are multimeric, depending on the level of redundancy accepted. We also analyse the structures in terms of the topological arrangement of their subunits and find that they form a small number of arrangements compared with all theoretically possible ones. This is because most complexes contain four subunits or less, and the large majority are homomeric. In addition, there is a strong tendency for symmetry in complexes, even for heteromeric complexes. Finally, through comparison of Biological Units in the Protein Data Bank with the Protein Quaternary Structure database, we identified many possible errors in quaternary structure assignments. Our classification, available as a database and Web server at http://www.3Dcomplex.org, will be a starting point for future work aimed at understanding the structure and evolution of protein complexes.

Unraveling chaotic attractors by complex networks and measurements of stock market complexity

International Nuclear Information System (INIS)

Cao, Hongduo; Li, Ying

2014-01-01

We present a novel method for measuring the complexity of a time series by unraveling a chaotic attractor modeled on complex networks. The complexity index R, which can potentially be exploited for prediction, has a similar meaning to the Kolmogorov complexity (calculated from the Lempel–Ziv complexity), and is an appropriate measure of a series' complexity. The proposed method is used to research the complexity of the world's major capital markets. None of these markets are completely random, and they have different degrees of complexity, both over the entire length of their time series and at a level of detail. However, developing markets differ significantly from mature markets. Specifically, the complexity of mature stock markets is stronger and more stable over time, whereas developing markets exhibit relatively low and unstable complexity over certain time periods, implying a stronger long-term price memory process

Unraveling chaotic attractors by complex networks and measurements of stock market complexity.

Science.gov (United States)

Cao, Hongduo; Li, Ying

2014-03-01

We present a novel method for measuring the complexity of a time series by unraveling a chaotic attractor modeled on complex networks. The complexity index R, which can potentially be exploited for prediction, has a similar meaning to the Kolmogorov complexity (calculated from the Lempel-Ziv complexity), and is an appropriate measure of a series' complexity. The proposed method is used to research the complexity of the world's major capital markets. None of these markets are completely random, and they have different degrees of complexity, both over the entire length of their time series and at a level of detail. However, developing markets differ significantly from mature markets. Specifically, the complexity of mature stock markets is stronger and more stable over time, whereas developing markets exhibit relatively low and unstable complexity over certain time periods, implying a stronger long-term price memory process.

Complex Correspondence Principle

International Nuclear Information System (INIS)

Bender, Carl M.; Meisinger, Peter N.; Hook, Daniel W.; Wang Qinghai

2010-01-01

Quantum mechanics and classical mechanics are distinctly different theories, but the correspondence principle states that quantum particles behave classically in the limit of high quantum number. In recent years much research has been done on extending both quantum and classical mechanics into the complex domain. These complex extensions continue to exhibit a correspondence, and this correspondence becomes more pronounced in the complex domain. The association between complex quantum mechanics and complex classical mechanics is subtle and demonstrating this relationship requires the use of asymptotics beyond all orders.

Uranium thiolate complexes

International Nuclear Information System (INIS)

Leverd, Pascal C.

1994-01-01

This research thesis proposes a new approach to the chemistry of uranium thiolate complexes as these compounds are very promising for various uses (in bio-inorganic chemistry, in some industrial processes like oil desulphurization). It more particularly addresses the U-S bond or more generally bonds between polarizable materials and hard metals. The author thus reports the study of uranium organometallic thiolates (tricyclo-penta-dienic and mono-cyclo-octa-tetraenylic complexes), and of uranium homoleptic thiolates (tetra-thiolate complexes, hexa-thiolate complexes, reactivity of homoleptic thiolate complexes) [fr

Clinical Complexity in Medicine: A Measurement Model of Task and Patient Complexity.

Science.gov (United States)

Islam, R; Weir, C; Del Fiol, G

2016-01-01

Complexity in medicine needs to be reduced to simple components in a way that is comprehensible to researchers and clinicians. Few studies in the current literature propose a measurement model that addresses both task and patient complexity in medicine. The objective of this paper is to develop an integrated approach to understand and measure clinical complexity by incorporating both task and patient complexity components focusing on the infectious disease domain. The measurement model was adapted and modified for the healthcare domain. Three clinical infectious disease teams were observed, audio-recorded and transcribed. Each team included an infectious diseases expert, one infectious diseases fellow, one physician assistant and one pharmacy resident fellow. The transcripts were parsed and the authors independently coded complexity attributes. This baseline measurement model of clinical complexity was modified in an initial set of coding processes and further validated in a consensus-based iterative process that included several meetings and email discussions by three clinical experts from diverse backgrounds from the Department of Biomedical Informatics at the University of Utah. Inter-rater reliability was calculated using Cohen's kappa. The proposed clinical complexity model consists of two separate components. The first is a clinical task complexity model with 13 clinical complexity-contributing factors and 7 dimensions. The second is the patient complexity model with 11 complexity-contributing factors and 5 dimensions. The measurement model for complexity encompassing both task and patient complexity will be a valuable resource for future researchers and industry to measure and understand complexity in healthcare.

Thinking Forbidden Thoughts: The Oedipus Complex as a Complex of Knowing.

Science.gov (United States)

Schein, Michael

2016-04-01

The Oedipus complex, considered by Freud the "nuclear complex of development," played a central role in the evolution of psychoanalytic thought. This paper returns to the point of transition from the seduction theory, Freud's initial theorem, to the oedipal model, and suggests that the Oedipus complex is first and foremost a text and as such contains a multiplicity of narratives. In particular, the author articulates the close relation between the Oedipus complex and the subject of knowing, postulating that underlying its surface level, the deep-level structure of this complex is one of knowing. As a complex of knowing it is of dual quality, both promoting and impeding the ability to know.

Complexity-management in SME : organization of complex relationships

NARCIS (Netherlands)

Gregus, M.; Mandorf, S.

2009-01-01

The complexity of companies' environment IS growmg. Complexity management and restructuring of small and medium-sized enterprises (SME) become big challenges of business studies in the next future. A chance could be seen in the use of e-business strategies and the implementation of information

Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemsitry in the region of Thulium, Lutetium, and Tantalum I. Results of Built in Spherical Symmetry in a Deformed Region

Energy Technology Data Exchange (ETDEWEB)

Hoffman, R. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2013-09-06

We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from Terbium (Z = 65) to Rhenium (Z = 75). Of particular interest are the cross sections on Tm, Lu, and Ta including reactions on isomeric targets.

Luminescence and energy transfer processes in Ce.sup.3+./sup. activated (Gd,Tb).sub.3./sub.Al.sub.5./sub.O.sub.12./sub. single crystalline films

Czech Academy of Sciences Publication Activity Database

Bartosiewicz, Karol; Babin, Vladimir; Mareš, Jiří A.; Beitlerová, Alena; Zorenko, Yu.; Iskaliyeva, A.; Gorbenko, V.; Bryknar, Z.; Nikl, Martin

2017-01-01

Roč. 188, Aug (2017), s. 60-66 ISSN 0022-2313 R&D Projects: GA ČR GA16-15569S; GA MŠk LO1409 EU Projects: European Commission(XE) 316906 - LUMINET Institutional support: RVO:68378271 Keywords : gadolinium terbium aluminum garnets * Ce 3+ * energy transfer * luminescence * single crystalline flms Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 2.686, year: 2016

Neutron resonance spins of 159Tb from experiments with polarized neutrons and polarized nuclei

International Nuclear Information System (INIS)

Alfimenkov, V.P.; Ivanenko, A.I.; Lason', L.; Mareev, Yu.D.; Ovchinnikov, O.N.; Pikel'ner, L.B.; Sharapov, Eh.I.

1976-01-01

Spins of 27 neutron resonances of 159 Tb with energies up to 114 eV have been measured using polarized neutrons and nuclei beams in the modernized time-of-flight spectrometer of the IBR-30 pulse reator. The direct measurements of the terbium resonances spins performed using polarized neutrons reaffirm the conclusion that there are no unstationary effects in the behaviour of 159 Tb neutron resonances in the energy range

Giant onsite electronic entropy enhances the performance of ceria for water splitting

DEFF Research Database (Denmark)

Naghavi, S. Shahab; Emery, Antoine A.; Hansen, Heine Anton

2017-01-01

lanthanides, and reaches a maximum value of ≈4.7 kB per oxygen vacancy for Ce4+/Ce3+ reduction. This unique and large positive entropy source in ceria explains its excellent performance for high-temperature catalytic redox reactions such as water splitting. Our calculations also show that terbium dioxide has...... a high electronic entropy and thus could also be a potential candidate for solar thermochemical reactions....

Managing Complexity

DEFF Research Database (Denmark)

Maylath, Bruce; Vandepitte, Sonia; Minacori, Patricia

2013-01-01

and into French. The complexity of the undertaking proved to be a central element in the students' learning, as the collaboration closely resembles the complexity of international documentation workplaces of language service providers. © Association of Teachers of Technical Writing.......This article discusses the largest and most complex international learning-by-doing project to date- a project involving translation from Danish and Dutch into English and editing into American English alongside a project involving writing, usability testing, and translation from English into Dutch...

Mathematics for electric engineers. Complex numbers; Mathematiques pour l`electricien. Nombres complexes

Energy Technology Data Exchange (ETDEWEB)

Rouxel, C. [Conservatoire National des Arts et Metiers (CNAM), 75 - Paris (France)

1999-05-01

Complex numbers are widely used in electrical engineering. This article is divided into 5 parts dealing successively with: the cartesian form of complex numbers (definition, conjugated complex numbers, graphical representation); the trigonometrical form of complex numbers (module and argument, trigonometrical form, exponential notation, multiplication and division of two complex numbers); Moivre and Euler formulae; applications (square root and second degree equation, n. roots, plan rotation and similarity); cissoidal transformation (definition, properties, applications to electricity: complex impedance in permanent sinusoidal regime, transfer function of a linear system in permanent regime, study of an example). (J.S.)

ComplexRec 2017

DEFF Research Database (Denmark)

a single step in the user's more complex background need. These background needs can often place a variety of constraints on which recommendations are interesting to the user and when they are appropriate. However, relatively little research has been done on these complex recommendation scenarios....... The ComplexRec 2017 workshop addressed this by providing an interactive venue for discussing approaches to recommendation in complex scenarios that have no simple one-size-fits-all-solution....

Complex variables

CERN Document Server

Fisher, Stephen D

1999-01-01

The most important topics in the theory and application of complex variables receive a thorough, coherent treatment in this introductory text. Intended for undergraduates or graduate students in science, mathematics, and engineering, this volume features hundreds of solved examples, exercises, and applications designed to foster a complete understanding of complex variables as well as an appreciation of their mathematical beauty and elegance. Prerequisites are minimal; a three-semester course in calculus will suffice to prepare students for discussions of these topics: the complex plane, basic

Complexity Management In Projects Between Rational Momentum And Complex Conditions

DEFF Research Database (Denmark)

Mac, Anita; Schlamovitz, Jesper

2015-01-01

Abstract: This study takes its departure in a model of complexity, developed by Stacey (1993), to test and discuss its practical benefit as perceived by practicing project managers. Based on a survey, the study finds that complexity is a phenomenon recognized by project managers, and complexity...... management is associated with benefits in the development of tasks and managing stakeholders. It is also associated with some difficulty in terms of an increased need for dialogue and a risk of creating goal ambiguity. Based on the findings, we conclude that classical project management approaches can...... benefit from incorporating complexity management....

Complexity management in projects between rational momentum and complex conditions

DEFF Research Database (Denmark)

Mac, Anita; Schlamovitz, Jesper

This study takes its departure in a model of complexity, developed by Stacey (1993), to test and discuss its practical benefit as perceived by practicing project managers. Based on a survey, the study finds that complexity is a phenomenon recognized by project managers, and complexity management...... is associated with benefits in the development of tasks and managing stakeholders. It is also associated with some difficulty in terms of an increased need for dialogue and a risk of creating goal ambiguity. Based on the findings, we conclude that classical project management approaches can benefit from...... incorporating complexity management....

Practical Implementation, Characterization and Applications of a Multi-Colour Time-Gated Luminescence Microscope

Science.gov (United States)

Zhang, Lixin; Zheng, Xianlin; Deng, Wei; Lu, Yiqing; Lechevallier, Severine; Ye, Zhiqiang; Goldys, Ewa M.; Dawes, Judith M.; Piper, James A.; Yuan, Jingli; Verelst, Marc; Jin, Dayong

2014-10-01

Time-gated luminescence microscopy using long-lifetime molecular probes can effectively eliminate autofluorescence to enable high contrast imaging. Here we investigate a new strategy of time-gated imaging for simultaneous visualisation of multiple species of microorganisms stained with long-lived complexes under low-background conditions. This is realized by imaging two pathogenic organisms (Giardia lamblia stained with a red europium probe and Cryptosporidium parvum with a green terbium probe) at UV wavelengths (320-400 nm) through synchronization of a flash lamp with high repetition rate (1 kHz) to a robust time-gating detection unit. This approach provides four times enhancement in signal-to-background ratio over non-time-gated imaging, while the average signal intensity also increases six-fold compared with that under UV LED excitation. The high sensitivity is further confirmed by imaging the single europium-doped Y2O2S nanocrystals (150 nm). We report technical details regarding the time-gating detection unit and demonstrate its compatibility with commercial epi-fluorescence microscopes, providing a valuable and convenient addition to standard laboratory equipment.

Fabrication and properties of highly luminescent materials from Tb(OH)3-SiO2 and Tb(OH)3-SiO2:Eu3+ nanotubes

International Nuclear Information System (INIS)

Tran Thu Huong; Tran Kim Anh; Le Quoc Minh

2009-01-01

Luminescent nanomaterials with one-dimensional (1D) structures have attracted much attention due to their unique properties and potential applications in nanophotonics and nanobiophotonics. In this paper, we report a synthesis of terbium - hydroxide - at - silica Tb(OH) 3 -SiO 2 and Tb(OH) 3 -SiO 2 :Eu 3+ nanotubes. Terbium - hydroxide tubes were synthesized by soft template method. The size of the tubes can be controlled precisely and have outer diameters ranging from 80 to 120 nm, wall thickness of about 30 nm, and lengths ranging from 300 to 800 nm. To fabricate core/shell materials, the seed growth method is used. FESEM, X-ray diffraction, Raman spectra of Tb(OH) 3 and Tb(OH) 3 -SiO 2 nanotubes were investigated. The photoluminescence (PL) spectrum of Tb(OH) 3 under 325 nm excitation consists of four main peaks at 488, 542, 582, and 618 nm. Furthermore, a preliminary suggestion for the mechanism of growth of the Tb(OH) 3 nanotubes using the soft - template synthesis technique has been proposed. The PL intensity from Tb(OH) 3 -SiO 2 or Tb(OH) 3 -SiO 2 :Eu 3+ nanotubes is much stronger than that of Tb(OH) 3 .

Simulation of the magnetocaloric effect in Tb nanofilms

Energy Technology Data Exchange (ETDEWEB)

Anselmo, Dory Hélio A. L., E-mail: doryh@dfte.ufrn.br [Departamento de Física Teórica e Experimental (DFTE), Universidade Federal do Rio Grande do Norte (UFRN), Natal-RN (Brazil); Mello, Vamberto D. [Departamento de Física,Universidade do Estado do Rio Grande do Norte (UERN), Mossoró-RN (Brazil); Vasconcelos, Manoel S. [Escola de Ciência e Tecnologia (ECT), Universidade Federal do Rio Grande do Norte (UFRN), Natal-RN (Brazil)

2014-03-31

Rare-earth (RE) metals have different magnetic structures resulting from the competition between the crystal-field and exchange interactions. When a magnetic field is applied it creates a third interaction and the magnetic structures are more complicated. In thin films, it is expected that even the magnetic arrangement itself can be strongly modified. Rare-earth helimagnets such as Terbium (Tb), Holmium (Ho) and Dysprosium (Dy) represent the best candidates to evidence such finite-size effects. This finite-size effect is caused by the reduced number of atoms in the direction perpendicular to the film plane that leads to a decrease of the total magnetic exchange energy. We report this contribution to the investigation of magnetocaloric effect (MCE) of thin Terbium films in the helimagnetic temperature range, from T{sub C} = 219 K to T{sub N} = 231 K, for external fields of the order of 1 kOe. We find that for strong fields, H = 50 kOe, the adiabatic temperature change ΔT near the Néel temperature is around 15 K for any thickness of Tb films. However large thickness effects are found for small values of the magnetic field. For field strength of the order of a few kOe, the thermocaloric efficiency increases significantly for ultrathin (nanomagnetic) films.

Line emissions from sonoluminescence in aqueous solutions of halide salts without noble gases

Energy Technology Data Exchange (ETDEWEB)

Liang, Jinfu, E-mail: liang.shi2007@163.com [The Key Laboratory of Modern Acoustics, Ministry of Education, Institution of Acoustics, Nanjing University, Nanjing 210093 (China); School of Physics and Electronic Science, Guizhou Normal University, Guiyang 550001 (China); Chen, Weizhong, E-mail: wzchen@nju.edu.cn [The Key Laboratory of Modern Acoustics, Ministry of Education, Institution of Acoustics, Nanjing University, Nanjing 210093 (China); Zhou, Chao; Cui, Weicheng; Chen, Zhan [The Key Laboratory of Modern Acoustics, Ministry of Education, Institution of Acoustics, Nanjing University, Nanjing 210093 (China)

2015-02-20

Line emissions of trivalent terbium (Tb{sup 3+}) ion were observed from single-bubble sonoluminescence (SL) in an aqueous solution of terbium chloride (TbCl{sub 3}) that contained no noble gas. In addition, sodium (Na) lines were observed in multi-bubble SL in aqueous solutions of various halide salts that contained no noble gas. These observations show that the halide ions, such as Cl{sup −}, Br{sup −}, and I{sup −}, help for line emissions as the noble gases. The intensity of a line emission depends on both the chemical species produced by cavitation bubbles and the temperature of SL bubble that responds to the driving ultrasound pressure. With the increase of driving pressure, some line emissions attached to the continuous spectrum may become increasingly clear, while other line emissions gradually become indistinct. - Highlights: • Line emissions of Tb(III) ions were observed without the presence of noble gases. • The halide ions help to generate a line emission during sonoluminescence. • The intensity of a line emission mainly depends on the bubble's temperature. • The definition of a line emission is related to the temperature of caviation bubble and the kind of host liquid.

Complexity Theory

Science.gov (United States)

Lee, William H K.

2016-01-01

A complex system consists of many interacting parts, generates new collective behavior through self organization, and adaptively evolves through time. Many theories have been developed to study complex systems, including chaos, fractals, cellular automata, self organization, stochastic processes, turbulence, and genetic algorithms.

Phospholyl-uranium complexes

International Nuclear Information System (INIS)

Gradoz, Philippe

1993-01-01

After having reported a bibliographical study on penta-methylcyclopentadienyl uranium complexes, and a description of the synthesis and radioactivity of uranium (III) and (IV) boron hydrides compounds, this research thesis reports the study of mono and bis-tetramethyl-phospholyl uranium complexes comprising chloride, boron hydride, alkyl and alkoxide ligands. The third part reports the comparison of structures, stabilities and reactions of homologue complexes in penta-methylcyclopentadienyl and tetramethyl-phospholyl series. The last part addresses the synthesis of tris-phospholyl uranium (III) and (IV) complexes. [fr

Complex saddle points and the sign problem in complex Langevin simulation

International Nuclear Information System (INIS)

Hayata, Tomoya; Hidaka, Yoshimasa; Tanizaki, Yuya

2016-01-01

We show that complex Langevin simulation converges to a wrong result within the semiclassical analysis, by relating it to the Lefschetz-thimble path integral, when the path-integral weight has different phases among dominant complex saddle points. Equilibrium solution of the complex Langevin equation forms local distributions around complex saddle points. Its ensemble average approximately becomes a direct sum of the average in each local distribution, where relative phases among them are dropped. We propose that by taking these phases into account through reweighting, we can solve the wrong convergence problem. However, this prescription may lead to a recurrence of the sign problem in the complex Langevin method for quantum many-body systems.

Complex and symplectic geometry

CERN Document Server

Medori, Costantino; Tomassini, Adriano

2017-01-01

This book arises from the INdAM Meeting "Complex and Symplectic Geometry", which was held in Cortona in June 2016. Several leading specialists, including young researchers, in the field of complex and symplectic geometry, present the state of the art of their research on topics such as the cohomology of complex manifolds; analytic techniques in Kähler and non-Kähler geometry; almost-complex and symplectic structures; special structures on complex manifolds; and deformations of complex objects. The work is intended for researchers in these areas.

Preparation of extractive resins for producing terbium-161

International Nuclear Information System (INIS)

De la Cruz B, C. C.; Monroy G, F.

2009-10-01

This paper presents the development of a methodology for extractive resins preparation to base of HDEHP, which allows to separation of Tb from Gd generating an own technology of preparation of these resins. The study included the extractive resins preparation from 6 different supports: kieselguhr Dg, alumina, red volcanic rock, chiluca, quarry and fluorite; two treatment types of of supports and varied concentrations of HDEHP extractant (di(2-etil hexyl) orthophosphoric acid), in order to determine which resin has improved efficiency of Gd and Tb separation, and radionuclide purity of 161 Tb. Resins were prepared to base of kieselguhr to determine the most appropriate silicon deposition process. Two silicon deposition treatments were realized: treatment I , by contact with silicon deposition solution (dimethyldichlorosilane / heptane 1:30) and treatment II by contact with vapors of dimethyldichlorosilane in vacuum. The extractant retention was carried out to different concentrations of HDEHP / acetone: 1:4, 1:8, 1:15, 1:20, 1:30 and 1:40. According to the results, there is not direct relation of HDEHP concentration used in extractive resins preparation to base of kieselguhr over the efficiency of Gd and Tb separation and of radionuclide purity of 161 Tb. The effect of support in the efficiency of Gd and Tb separation was studied to prepare resins with the supports kieselguhr, alumina, quarry, chiluca, volcanic rock and fluorite, using the silicon deposition treatment II for the supports and a concentration of HDEHP / acetone 1:20, for extractant retention. Only resins based on kieselguhr could separate to Gd from Tb quantitatively, the resin at a concentration of HDEHP / Acetone 1:20 was the best results obtained in Gd and Tb separation, achieving a separation efficiency greater than 90% and a radionuclide purity higher than 99%. (Author)

The systems terbium (holmium) nitrate-piperidine nitrate-water

International Nuclear Information System (INIS)

Khisaeva, D.A.; Zhuravlev, E.F.; Semenova, Eh.B.

1982-01-01

Using the method of cross sections at 25 and 50 deg C solubility in the systems Tb(NO 3 ) 2 -C 5 H 10 NHxHNO 3 -H 2 O and Ho(NO 3 ) 3 -C 5 H 10 NHxHNO 3 -H 2 O has been studied. The systems are characterized by chemical interaction of components. Solubility isotherms have crystallization fields of solid phases of the composition Tb(NO 3 ) 3 x3[C 5 H 10 NHxHNO 3 ]x3H 2 O and Ho(NO 3 ) 3 x2[C 5 H 10 NHxHNO 3 ]. The compounds detected are singled out preparatively, their IR spectra are studied, their thermogravimetric analysis is carried out. Investigation results are compared with similar systems formed by nitrates of other representatives of rare earth group

Spin waves in terbium. II. Magnon-phonon interaction

International Nuclear Information System (INIS)

Jensen, J.; Houmann, J.G.

1975-01-01

The selection rules for the linear couplings between magnons and phonons propagating in the c direction of a simple basal-plane hcp ferromagnet are determined by general symmetry considerations. The acoustic-optical magnon-phonon interactions observed in the heavy-rare-earth metals have been explained by Liu as originating from the mixing of the spin states of the conduction electrons due to the spin-orbit coupling. We find that this coupling mechanism introduces interactions which violate the selection rules for a simple ferromagnet. The interactions between the magnons and phonons propagating in the c direction of Tb have been studied experimentally by means of inelastic neutron scatttering. The magnons are coupled to both the acoustic- and optical-transverse phonons. By studying the behavior of the acoustic-optical coupling, we conclude that it is a spin-mixed-induced coupling as proposed by Liu. The coupled magnon--transverse-phonon system for the c direction of Tb is analyzed in detail, and the strengths of the couplings are deduced as a function of wave vector by combining the experimental studies with the theory

Adaptive generalized combination complex synchronization of uncertain real and complex nonlinear systems

Energy Technology Data Exchange (ETDEWEB)

Wang, Shi-bing, E-mail: wang-shibing@dlut.edu.cn, E-mail: wangxy@dlut.edu.cn [School of Computer and Information Engineering, Fuyang Normal University, Fuyang 236041 (China); Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024 (China); Wang, Xing-yuan, E-mail: wang-shibing@dlut.edu.cn, E-mail: wangxy@dlut.edu.cn [Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024 (China); Wang, Xiu-you [School of Computer and Information Engineering, Fuyang Normal University, Fuyang 236041 (China); Zhou, Yu-fei [College of Electrical Engineering and Automation, Anhui University, Hefei 230601 (China)

2016-04-15

With comprehensive consideration of generalized synchronization, combination synchronization and adaptive control, this paper investigates a novel adaptive generalized combination complex synchronization (AGCCS) scheme for different real and complex nonlinear systems with unknown parameters. On the basis of Lyapunov stability theory and adaptive control, an AGCCS controller and parameter update laws are derived to achieve synchronization and parameter identification of two real drive systems and a complex response system, as well as two complex drive systems and a real response system. Two simulation examples, namely, ACGCS for chaotic real Lorenz and Chen systems driving a hyperchaotic complex Lü system, and hyperchaotic complex Lorenz and Chen systems driving a real chaotic Lü system, are presented to verify the feasibility and effectiveness of the proposed scheme.

A new generative complexity science of learning for a complex pedagogy

NARCIS (Netherlands)

Jörg, T.

2007-01-01

Proposal for the SIG Chaos and Complexity Theories at AERA 2007 Title: A New Generative Complexity Science of Learning for a Complex Pedagogy Ton Jörg IVLOS Institute of Education University of Utrecht The Netherlands A.G.D.Jorg@ivlos.uu.nl Introduction My paper focuses on the link between thinking

Quantum complex rotation and uniform semiclassical calculations of complex energy eigenvalues

International Nuclear Information System (INIS)

Connor, J.N.L.; Smith, A.D.

1983-01-01

Quantum and semiclassical calculations of complex energy eigenvalues have been carried out for an exponential potential of the form V 0 r 2 exp(-r) and Lennard-Jones (12,6) potential. A straightforward method, based on the complex coordinate rotation technique, is described for the quantum calculation of complex eigenenergies. For singular potentials, the method involves an inward and outward integration of the radial Schroedinger equation, followed by matching of the logarithmic derivatives of the wave functions at an intermediate point. For regular potentials, the method is simpler, as only an inward integration is required. Attention is drawn to the World War II researches of Hartree and co-workers who anticipated later quantum mechanical work on the complex rotation method. Complex eigenenergies are also calculated from a uniform semiclassical three turning point quantization formula, which allows for the proximity of the outer pair of complex turning points. Limiting cases of this formula, which are valid for very narrow or very broad widths, are also used in the calculations. We obtain good agreement between the semiclassical and quantum results. For the Lennard-Jones (12,6) potential, we compare resonance energies and widths from the complex energy definition of a resonance with those obtained from the time delay definition

Complex Constructivism: A Theoretical Model of Complexity and Cognition

Science.gov (United States)

Doolittle, Peter E.

2014-01-01

Education has long been driven by its metaphors for teaching and learning. These metaphors have influenced both educational research and educational practice. Complexity and constructivism are two theories that provide functional and robust metaphors. Complexity provides a metaphor for the structure of myriad phenomena, while constructivism…

Complexity in phonology: The complex consonants of simple CV ...

African Journals Online (AJOL)

The main objective of this article is to investigate the interplay of simplicity and complexity in the phonological structure of Zezuru. The article argues that Zezuru affricates, prenasalised consonants (NCs) and velarised consonants (Cws) are subsegmentally complex segments which function as simple onsets. Treating them ...

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 ...

Nuclear weapons complex

International Nuclear Information System (INIS)

Rezendes, V.S.

1991-03-01

In this book, GAO characterizes DOE's January 1991 Nuclear Weapons Complex Reconfiguration Study as a starting point for reaching agreement on solutions to many of the complex's safety and environmental problems. Key decisions still need to be made about the size of the complex, where to relocate plutonium operations, what technologies to use for new tritium production, and what to do with excess plutonium. The total cost for reconfiguring and modernizing the complex is still uncertain, and some management issues remain unresolved. Congress faces a difficult task in making test decisions given the conflicting demands for scarce resources in a time of growing budget deficits and war in the Persian Gulf

Complex Networks

CERN Document Server

Evsukoff, Alexandre; González, Marta

2013-01-01

In the last decade we have seen the emergence of a new inter-disciplinary field focusing on the understanding of networks which are dynamic, large, open, and have a structure sometimes called random-biased. The field of Complex Networks is helping us better understand many complex phenomena such as the spread of  deseases, protein interactions, social relationships, to name but a few. Studies in Complex Networks are gaining attention due to some major scientific breakthroughs proposed by network scientists helping us understand and model interactions contained in large datasets. In fact, if we could point to one event leading to the widespread use of complex network analysis is the availability of online databases. Theories of Random Graphs from Erdös and Rényi from the late 1950s led us to believe that most networks had random characteristics. The work on large online datasets told us otherwise. Starting with the work of Barabási and Albert as well as Watts and Strogatz in the late 1990s, we now know th...

The relevance of rare earth elements to nuclear medicine

International Nuclear Information System (INIS)

Cox, P.H.

1998-01-01

Full text: The lanthanides are an interesting series of metallic elements which have almost identical chemical characteristics and which offer a variety of radioisotopes with differing energy spectra suitable for open source therapy. Their inorganic salts tend to form chemically and biological stable colloids which have proved to be useful for intercavity therapies, in particular for synovectomy. Yttrium-90 silicate is a standard product for large joints with a thick synovium whilst for smaller joints Erbium-169, with its shorter tissue penetration, is more widely used for smaller joints to reduce the risk of radiation induced bone necrosis. Recently the development of an inert biodegradable colloid, chitosan, labelled with Holmium 166. for intercavity therapy of cystic brain tumours has been reported. Yttrium-90 has been chelated to peptide and antibody fragments for tumour targeting as a potentially more effective radionuclide than Iodine-131. The search for alternatives to Strontium-89 for the palliative treatment of pain arising from bone metastases has led to the introduction of diphosphonate complexes of Samarium-153, Lutetium-177 and Holmium-166. These complexes are of special interest because the radionuclides can be produced economically in developing countries. Terbium-149, an alpha emitter, has been mentioned as a possible therapeutic radionuclide. Yttrium-90 and Holmium-166 can an both be made available as generator products which is an added potential advantage for developing nuclear medical applications

Power grid complexity

Energy Technology Data Exchange (ETDEWEB)

Mei, Shengwei; Zhang, Xuemin [Tsinghua Univ., Beijing, BJ (China). Dept. of Electrical Engineering; Cao, Ming [Groningen Univ. (Netherlands). Faculty of Mathematics and Natural Sciences

2011-07-01

''Power Grid Complexity'' introduces the complex system theory known as self-organized criticality (SOC) theory and complex network theory, and their applications to power systems. It studies the network characteristics of power systems, such as their small-world properties, structural vulnerability, decomposition and coordination strategies, and simplification and equivalence methods. The book also establishes four blackout models based on SOC theory through which the SOC of power systems is studied at both the macroscopic and microscopic levels. Additionally, applications of complex system theory in power system planning and emergency management platforms are also discussed in depth. This book can serve as a useful reference for engineers and researchers working with power systems. (orig.)

Coxeter-like complexes

Directory of Open Access Journals (Sweden)

Eric Babson

2004-12-01

Full Text Available Motivated by the Coxeter complex associated to a Coxeter system (W,S, we introduce a simplicial regular cell complex Δ(G,S with a G-action associated to any pair (G,S where G is a group and S is a finite set of generators for G which is minimal with respect to inclusion. We examine the topology of Δ(G,S, and in particular the representations of G on its homology groups. We look closely at the case of the symmetric group S n minimally generated by (not necessarily adjacent transpositions, and their type-selected subcomplexes. These include not only the Coxeter complexes of type A, but also the well-studied chessboard complexes.

Technetium complexation by macrocyclic compounds

International Nuclear Information System (INIS)

Li Fan Yu.

1983-01-01

Research in nuclear medicine are directed towards the labelling of biological molecules, however, sup(99m)Tc does not show sufficient affinity for these molecules. The aim of this study was to evaluate the ability of macrocyclic compounds to bind strongly technetium in order to be used as complexation intermediate. The reducing agents used were a stannous complex and sodium dithionite. Cryptates and polyesters are not good complexing agents. They form two complexes: a 2:1 sandwich complex or 3:2 and a 1:1 complex. Cyclams are good complexing agents for technetium their complexations strength was determined by competition with pyrophosphate, gluconate and DTPA. Using the method of ligand exchange, the oxidation state of technetium in the Tc-cyclam complex was IV or V. They are 1:1 cationic complexes, the complex charge is +1. The biodistribution in rats of labelling solutions containing (cyclam 14 ane N 4 ) C 12 H 25 shows a good urinary excretion without intoxication risks [fr

[Tissue-specific nucleoprotein complexes].

Science.gov (United States)

Riadnova, I Iu; Shataeva, L K; Khavinson, V Kh

2000-01-01

A method of isolation of native nucleorprotein complexes from cattle cerebral cortex, thymus, and liver was developed. Compositions of these complexes were studied by means of gel-chromatography and ion-exchange chromatography. These preparations were shown to consist of several fractions of proteins and their complexes differ by molecular mass and electro-chemical properties. Native nucleoprotein complexes revealed high tissue specific activity, which was not species-specific.

Complex analysis and geometry

CERN Document Server

Silva, Alessandro

1993-01-01

The papers in this wide-ranging collection report on the results of investigations from a number of linked disciplines, including complex algebraic geometry, complex analytic geometry of manifolds and spaces, and complex differential geometry.

On Complex Random Variables

Directory of Open Access Journals (Sweden)

Anwer Khurshid

2012-07-01

Full Text Available Normal 0 false false false EN-US X-NONE X-NONE In this paper, it is shown that a complex multivariate random variable  is a complex multivariate normal random variable of dimensionality if and only if all nondegenerate complex linear combinations of  have a complex univariate normal distribution. The characteristic function of  has been derived, and simpler forms of some theorems have been given using this characterization theorem without assuming that the variance-covariance matrix of the vector  is Hermitian positive definite. Marginal distributions of  have been given. In addition, a complex multivariate t-distribution has been defined and the density derived. A characterization of the complex multivariate t-distribution is given. A few possible uses of this distribution have been suggested.

Complex Systems: An Introduction

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 9. Complex Systems: An Introduction - Anthropic Principle, Terrestrial Complexity, Complex Materials. V K Wadhawan. General Article Volume 14 Issue 9 September 2009 pp 894-906 ...

Simplicial complexes of graphs

CERN Document Server

Jonsson, Jakob

2008-01-01

A graph complex is a finite family of graphs closed under deletion of edges. Graph complexes show up naturally in many different areas of mathematics, including commutative algebra, geometry, and knot theory. Identifying each graph with its edge set, one may view a graph complex as a simplicial complex and hence interpret it as a geometric object. This volume examines topological properties of graph complexes, focusing on homotopy type and homology. Many of the proofs are based on Robin Forman's discrete version of Morse theory. As a byproduct, this volume also provides a loosely defined toolbox for attacking problems in topological combinatorics via discrete Morse theory. In terms of simplicity and power, arguably the most efficient tool is Forman's divide and conquer approach via decision trees; it is successfully applied to a large number of graph and digraph complexes.

Actinide cation-cation complexes

International Nuclear Information System (INIS)

Stoyer, N.J.; Seaborg, G.T.

1994-12-01

The +5 oxidation state of U, Np, Pu, and Am is a linear dioxo cation (AnO 2 + ) with a formal charge of +1. These cations form complexes with a variety of other cations, including actinide cations. Other oxidation states of actinides do not form these cation-cation complexes with any cation other than AnO 2 + ; therefore, cation-cation complexes indicate something unique about AnO 2 + cations compared to actinide cations in general. The first cation-cation complex, NpO 2 + ·UO 2 2+ , was reported by Sullivan, Hindman, and Zielen in 1961. Of the four actinides that form AnO 2 + species, the cation-cation complexes of NpO 2 + have been studied most extensively while the other actinides have not. The only PuO 2 + cation-cation complexes that have been studied are with Fe 3+ and Cr 3+ and neither one has had its equilibrium constant measured. Actinides have small molar absorptivities and cation-cation complexes have small equilibrium constants; therefore, to overcome these obstacles a sensitive technique is required. Spectroscopic techniques are used most often to study cation-cation complexes. Laser-Induced Photacoustic Spectroscopy equilibrium constants for the complexes NpO 2 + ·UO 2 2+ , NpO 2 + ·Th 4+ , PuO 2 + ·UO 2 2+ , and PuO 2 + ·Th 4+ at an ionic strength of 6 M using LIPAS are 2.4 ± 0.2, 1.8 ± 0.9, 2.2 ± 1.5, and ∼0.8 M -1

Conducting metal dithiolate complexes

DEFF Research Database (Denmark)

Underhill, A. E.; Ahmad, M. M.; Turner, D. J.

1985-01-01

Further work on the chemical composition of the one-dimensional metallic metal dithiolene complex Li-Pt(mnt) is reported. The electrical conduction and thermopower properties of the nickel and palladium complexes are reported and compared with those of the platinum compound......Further work on the chemical composition of the one-dimensional metallic metal dithiolene complex Li-Pt(mnt) is reported. The electrical conduction and thermopower properties of the nickel and palladium complexes are reported and compared with those of the platinum compound...

Curcumin complexation with cyclodextrins by the autoclave process: Method development and characterization of complex formation.

Science.gov (United States)

Hagbani, Turki Al; Nazzal, Sami

2017-03-30

One approach to enhance curcumin (CUR) aqueous solubility is to use cyclodextrins (CDs) to form inclusion complexes where CUR is encapsulated as a guest molecule within the internal cavity of the water-soluble CD. Several methods have been reported for the complexation of CUR with CDs. Limited information, however, is available on the use of the autoclave process (AU) in complex formation. The aims of this work were therefore to (1) investigate and evaluate the AU cycle as a complex formation method to enhance CUR solubility; (2) compare the efficacy of the AU process with the freeze-drying (FD) and evaporation (EV) processes in complex formation; and (3) confirm CUR stability by characterizing CUR:CD complexes by NMR, Raman spectroscopy, DSC, and XRD. Significant differences were found in the saturation solubility of CUR from its complexes with CD when prepared by the three complexation methods. The AU yielded a complex with expected chemical and physical fingerprints for a CUR:CD inclusion complex that maintained the chemical integrity and stability of CUR and provided the highest solubility of CUR in water. Physical and chemical characterizations of the AU complexes confirmed the encapsulated of CUR inside the CD cavity and the transformation of the crystalline CUR:CD inclusion complex to an amorphous form. It was concluded that the autoclave process with its short processing time could be used as an alternate and efficient methods for drug:CD complexation. Copyright © 2017 Elsevier B.V. All rights reserved.

Complex analysis

CERN Document Server

Freitag, Eberhard

2005-01-01

The guiding principle of this presentation of ``Classical Complex Analysis'' is to proceed as quickly as possible to the central results while using a small number of notions and concepts from other fields. Thus the prerequisites for understanding this book are minimal; only elementary facts of calculus and algebra are required. The first four chapters cover the essential core of complex analysis: - differentiation in C (including elementary facts about conformal mappings) - integration in C (including complex line integrals, Cauchy's Integral Theorem, and the Integral Formulas) - sequences and series of analytic functions, (isolated) singularities, Laurent series, calculus of residues - construction of analytic functions: the gamma function, Weierstrass' Factorization Theorem, Mittag-Leffler Partial Fraction Decomposition, and -as a particular highlight- the Riemann Mapping Theorem, which characterizes the simply connected domains in C. Further topics included are: - the theory of elliptic functions based on...

Complexes and imagination.

Science.gov (United States)

Kast, Verena

2014-11-01

Fantasies as imaginative activities are seen by Jung as expressions of psychic energy. In the various descriptions of active imagination the observation of the inner image and the dialogue with inner figures, if possible, are important. The model of symbol formation, as Jung describes it, can be experienced in doing active imagination. There is a correspondence between Jung's understanding of complexes and our imaginations: complexes develop a fantasy life. Complex episodes are narratives of difficult dysfunctional relationship episodes that have occurred repeatedly and are internalized with episodic memory. This means that the whole complex episode (the image for the child and the image for the aggressor, connected with emotions) is internalized and can get constellated in everyday relationship. Therefore inner dialogues do not necessarily qualify as active imaginations, often they are the expression of complex-episodes, very similar to fruitless soliloquies. If imaginations of this kind are repeated, new symbols and new possibilities of behaviour are not found. On the contrary, old patterns of behaviour and fantasies are perpetuated and become cemented. Imaginations of this kind need an intervention by the analyst. In clinical examples different kinds of imaginations are discussed. © 2014, The Society of Analytical Psychology.

Leading healthcare in complexity.

Science.gov (United States)

Cohn, Jeffrey

2014-12-01

Healthcare institutions and providers are in complexity. Networks of interconnections from relationships and technology create conditions in which interdependencies and non-linear dynamics lead to surprising, unpredictable outcomes. Previous effective approaches to leadership, focusing on top-down bureaucratic methods, are no longer effective. Leading in complexity requires leaders to accept the complexity, create an adaptive space in which innovation and creativity can flourish and then integrate the successful practices that emerge into the formal organizational structure. Several methods for doing adaptive space work will be discussed. Readers will be able to contrast traditional leadership approaches with leading in complexity. They will learn new behaviours that are required of complexity leaders, along with challenges they will face, often from other leaders within the organization.

Analysis and control of complex dynamical systems robust bifurcation, dynamic attractors, and network complexity

CERN Document Server

Imura, Jun-ichi; Ueta, Tetsushi

2015-01-01

This book is the first to report on theoretical breakthroughs on control of complex dynamical systems developed by collaborative researchers in the two fields of dynamical systems theory and control theory. As well, its basic point of view is of three kinds of complexity: bifurcation phenomena subject to model uncertainty, complex behavior including periodic/quasi-periodic orbits as well as chaotic orbits, and network complexity emerging from dynamical interactions between subsystems. Analysis and Control of Complex Dynamical Systems offers a valuable resource for mathematicians, physicists, and biophysicists, as well as for researchers in nonlinear science and control engineering, allowing them to develop a better fundamental understanding of the analysis and control synthesis of such complex systems.

Modified projective synchronization with complex scaling factors of uncertain real chaos and complex chaos

International Nuclear Information System (INIS)

Zhang Fang-Fang; Liu Shu-Tang; Yu Wei-Yong

2013-01-01

To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors (CMPS) of real chaotic systems and complex chaotic systems, where complex scaling factors establish a link between real chaos and complex chaos. Considering all situations of unknown parameters and pseudo-gradient condition, we design adaptive CMPS schemes based on the speed-gradient method for the real drive chaotic system and complex response chaotic system and for the complex drive chaotic system and the real response chaotic system, respectively. The convergence factors and dynamical control strength are added to regulate the convergence speed and increase robustness. Numerical simulations verify the feasibility and effectiveness of the presented schemes. (general)

Selenophene transition metal complexes

Energy Technology Data Exchange (ETDEWEB)

White, Carter James [Iowa State Univ., Ames, IA (United States)

1994-07-27

This research shows that selenophene transition metal complexes have a chemistry that is similar to their thiophene analogs. Selenophene coordination has been demonstrated and confirmed by molecular structure in both the η⁵- and the η¹(Se)-coordination modes. The reaction chemistry of selenophene complexes closely resembles that of the analogous thiophene complexes. One major difference, however, is that selenophene is a better donor ligand than thiophene making the selenophene complexes more stable than the corresponding thiophene complexes. The ⁷⁷Se NMR chemical shift values for selenophene complexes fall within distinct regions primarily depending on the coordination mode of the selenophene ligand. In the final paper, the C-H bond activation of η¹(S)-bound thiophenes, η¹(S)-benzothiophene and η¹(Se)-bound selenophenes has been demonstrated. The deprotonation and rearrangement of the η¹(E)-bound ligand to the carbon bound L-yl complex readily occurs in the presence of base. Reprotonation with a strong acid gives a carbene complex that is unreactive towards nucleophilic attack at the carbene carbon and is stable towards exposure to air. The molecular structure of [Cp(NO)(PPh₃)Re(2-benzothioenylcarbene)]O₃SCF₃ was determined and contains a Re-C bond with substantial double bond character. Methyl substitution for the thienylcarbene or selenylcarbene gives a carbene that rearranges thermally to give back the η¹(E)-bound complex. Based on these model reactions, a new mechanism for the H/D exchange of thiophene over the hydrodesulfurization catalyst has been proposed.

Photocytotoxic lanthanide complexes

Indian Academy of Sciences (India)

Among many applications of lanthanides, gadolinium complexes are used as magnetic resonance imaging (MRI) contrast agents in clinical radiology and luminescent lanthanides for bioanalysis, imaging and sensing. The chemistry of photoactive lanthanide complexes showing biological applications is of recent origin.

Physical Complexity and Cognitive Evolution

Science.gov (United States)

Jedlicka, Peter

Our intuition tells us that there is a general trend in the evolution of nature, a trend towards greater complexity. However, there are several definitions of complexity and hence it is difficult to argue for or against the validity of this intuition. Christoph Adami has recently introduced a novel measure called physical complexity that assigns low complexity to both ordered and random systems and high complexity to those in between. Physical complexity measures the amount of information that an organism stores in its genome about the environment in which it evolves. The theory of physical complexity predicts that evolution increases the amount of `knowledge' an organism accumulates about its niche. It might be fruitful to generalize Adami's concept of complexity to the entire evolution (including the evolution of man). Physical complexity fits nicely into the philosophical framework of cognitive biology which considers biological evolution as a progressing process of accumulation of knowledge (as a gradual increase of epistemic complexity). According to this paradigm, evolution is a cognitive `ratchet' that pushes the organisms unidirectionally towards higher complexity. Dynamic environment continually creates problems to be solved. To survive in the environment means to solve the problem, and the solution is an embodied knowledge. Cognitive biology (as well as the theory of physical complexity) uses the concepts of information and entropy and views the evolution from both the information-theoretical and thermodynamical perspective. Concerning humans as conscious beings, it seems necessary to postulate an emergence of a new kind of knowledge - a self-aware and self-referential knowledge. Appearence of selfreflection in evolution indicates that the human brain reached a new qualitative level in the epistemic complexity.

Effect of terbium substitution on the magnetocaloric properties of Gd3Ga5O12

International Nuclear Information System (INIS)

Reshmi, C.P.; Savitha Pillai, S.; Varma, Manoj Raama; Suresh, K.G.

2011-01-01

The magnetic refrigeration is an environment friendly cooling technology based on magnetocaloric effect. The most crucial ingredient behind a magnetic refrigerator is a magnetic material which possesses large magnetocaloric effect. Certain materials when placed in a magnetic field suddenly get heats up and suddenly cooled down by the application and the removal of magnetic field due to their change in entropy. This is measured either in terms of isothermal entropy change and adiabatic temperature change observed when the applied magnetic field is varied. The refrigerators which operate below 15K have applications in liquefying helium and for the development of space based cooling system for the space crafts. The material of choice in this temperature range is rare earth gallium garnets. Rare earth garnets are complex ceramic oxides having the chemical formula A 3 B 2 C 3 O 12 have attracted attention due to their interesting magnetic properties. The magnetism in R 3 Ga 5 O 12 is due to the exchange interaction between the rare earth spins. In the proposed work we have chosen Gd 3 Ga 5 O 12 as parent material, substituted Tb systematically in the place of Gd. The structural studies were done by using Rietveld analysis of X-Ray diffraction. There is a systematic variation of volume and lattice parameter upon substitution of Tb. The magnetic characterizations were done by a vibrating sample magnetometer. The experimental magnetic moments of the materials were calculated from the M-T curve by using Curie-Weiss fit and are good agreement with the theoretical values. There is a systematic increase of magnetic moments by Tb substitution. The magnetocaloric effect is calculated by using the integrated Maxwell's relation from the magnetization data. At low magnetic fields the Tb substituted compounds show good MCE values than GGG. Tb substitution enhances the magnetocaloric effect at low magnetic fields and the ΔS M values are higher for x = 1 and 3 at 1T. Hence these

Functionalized active-nucleus complex sensor

Science.gov (United States)

Pines, Alexander; Wemmer, David E.; Spence, Megan; Rubin, Seth

2003-11-25

A functionalized active-nucleus complex sensor that selectively associates with one or more target species, and a method for assaying and screening for one or a plurality of target species utilizing one or a plurality of functionalized active-nucleus complexes with at least two of the functionalized active-nucleus complexes having an attraction affinity to different corresponding target species. The functionalized active-nucleus complex has an active-nucleus and a targeting carrier. The method involves functionalizing an active-nucleus, for each functionalized active-nucleus complex, by incorporating the active-nucleus into a macromolucular or molecular complex that is capable of binding one of the target species and then bringing the macromolecular or molecular complexes into contact with the target species and detecting the occurrence of or change in a nuclear magnetic resonance signal from each of the active-nuclei in each of the functionalized active-nucleus complexes.

Complex Neutrosophic Subsemigroups and Ideals

Directory of Open Access Journals (Sweden)

Muhammad Gulistan

2018-01-01

Full Text Available In this article we study the idea of complex neutrosophic subsemigroups. We define the Cartesian product of complex neutrosophic subsemigroups, give some examples and study some of its related results. We also define complex neutrosophic (left, right, interior ideal in semigroup. Furthermore, we introduce the concept of characteristic function of complex neutrosophic sets, direct product of complex neutrosophic sets and study some results prove on its.

Transition Complexity of Incomplete DFAs

Directory of Open Access Journals (Sweden)

Yuan Gao

2010-08-01

Full Text Available In this paper, we consider the transition complexity of regular languages based on the incomplete deterministic finite automata. A number of results on Boolean operations have been obtained. It is shown that the transition complexity results for union and complementation are very different from the state complexity results for the same operations. However, for intersection, the transition complexity result is similar to that of state complexity.

Subsumed complexity: abiogenesis as a by-product of complex energy transduction

Science.gov (United States)

Adam, Z. R.; Zubarev, D.; Aono, M.; Cleaves, H. James

2017-11-01

The origins of life bring into stark relief the inadequacy of our current synthesis of thermodynamic, chemical, physical and information theory to predict the conditions under which complex, living states of organic matter can arise. Origins research has traditionally proceeded under an array of implicit or explicit guiding principles in lieu of a universal formalism for abiogenesis. Within the framework of a new guiding principle for prebiotic chemistry called subsumed complexity, organic compounds are viewed as by-products of energy transduction phenomena at different scales (subatomic, atomic, molecular and polymeric) that retain energy in the form of bonds that inhibit energy from reaching the ground state. There is evidence for an emergent level of complexity that is overlooked in most conceptualizations of abiogenesis that arises from populations of compounds formed from atomic energy input. We posit that different forms of energy input can exhibit different degrees of dissipation complexity within an identical chemical medium. By extension, the maximum capacity for organic chemical complexification across molecular and macromolecular scales subsumes, rather than emerges from, the underlying complexity of energy transduction processes that drive their production and modification. This article is part of the themed issue 'Reconceptualizing the origins of life'.

Spectroscopy of plutonium-organic complexes

International Nuclear Information System (INIS)

Richmann, M.K.; Reed, D.T.

1995-01-01

Information on the spectroscopy of plutonium-organic complexes is needed to help establish the speciation of these complexes under environmentally relevant conditions. Laser photoacoustic spectroscopy (LPAS) and absorption spectrometry were used to characterize the Pu(IV)-citrate and Pu(IV)-nitrilotriacetic acid (NTA) complexes at concentrations of 10 -3 --10 -7 M in aqueous solution. Good agreement was observed between the band shape of the LPAS and absorption spectra for the Pu(IV)-NTA complex. Agreement for the Pu(IV)-citrate complex was not quite as good. In both cases, a linear dependence of the LPAS signal on laser power and total concentration of the complexes was noted. This work is part of an ongoing research effort to study key subsurface interactions of plutonium-organic complexes

Complex Networks IX

CERN Document Server

Coronges, Kate; Gonçalves, Bruno; Sinatra, Roberta; Vespignani, Alessandro; Proceedings of the 9th Conference on Complex Networks; CompleNet 2018

2018-01-01

This book aims to bring together researchers and practitioners working across domains and research disciplines to measure, model, and visualize complex networks. It collects the works presented at the 9th International Conference on Complex Networks (CompleNet) 2018 in Boston, MA in March, 2018. With roots in physical, information and social science, the study of complex networks provides a formal set of mathematical methods, computational tools and theories to describe prescribe and predict dynamics and behaviors of complex systems. Despite their diversity, whether the systems are made up of physical, technological, informational, or social networks, they share many common organizing principles and thus can be studied with similar approaches. This book provides a view of the state-of-the-art in this dynamic field and covers topics such as group decision-making, brain and cellular connectivity, network controllability and resiliency, online activism, recommendation systems, and cyber security.

What is complex in the complex world? Niklas Luhmann and the theory of social systems

Directory of Open Access Journals (Sweden)

Clarissa Eckert Baeta Neves

Full Text Available This paper discusses Niklas Luhmann's understanding of complexity, its function in the theory and the different ways of its use. It starts with the paradigmatic change that occurred in the field of general Science, with the rupture of the Newtonian model. In the 20th century, the paradigm of order, symmetry, regularity, regulation of the intellect to things, collapses.Based on new formulations of Physics, Chemistry, etc., a new universe is built on bases radically opposed to those of modern Science.Chaos, the procedural irreversibility, indeterminism, the observer and the complexity are rehabilitated.This new conceptual context served as substratum to Niklas Luhmann's theoretical reflection.With his Theory of Social Systems, he proposes the reduction of the world's complexity.Social systems have the function of reducing complexity because of their difference in relation to the environment.On the other hand, the reduction of complexity also creates its own complexity. Luhmann defines complexity as the moment when it is not possible anymore for each element to relate at any moment with all the others. Complexity forces the selection, what means contingency and risk. Luhmann expands the concept of complexity when he introduces the figure of the observer and the distinction of complexity as a unit of a multiplicity. He also deals with the limit of relations in connection, the time factor, the self-reference of operations and the representation of complexity in the form of sense. To conclude, the paper discusses the complexity in the system of science, the way it reduces internal and external complexity, in accordance in its own operative basis.

Complexity Leadership: A Theoretical Perspective

Science.gov (United States)

Baltaci, Ali; Balci, Ali

2017-01-01

Complex systems are social networks composed of interactive employees interconnected through collaborative, dynamic ties such as shared goals, perspectives and needs. Complex systems are largely based on "the complex system theory". The complex system theory focuses mainly on finding out and developing strategies and behaviours that…

Organotin complexes with phosphines

International Nuclear Information System (INIS)

Passos, B. de F.T.; Jesus Filho, M.F. de; Filgueiras, C.A.L.; Abras, A.

1988-01-01

A series of organotin complexes was prepared involving phosphines bonded to the organotin moiety. The series include derivatives of SnCl x Ph 4-x (where x varied from zero to four with the phosphines Ph 3 P, (Ph 2 P)CH 2 , (Ph 2 P) 2 (CH 2 ) 2 , cis-(Ph 2 P)CH 2 , and CH 3 C(CH 2 PPh 2 ) 3 . A host of new complexes was obtained, showing different stoichiometries, bonding modes, and coordination numbers around the tin atom. These complexes were characterized by several different chemical and physical methods. The 119 Sn Moessbauer parameters varied differently. Whereas isomer shift values did not great variation for each group of complexs with the same organotin parent (SnCl x Ph 4-x ), reflecting a small change in s charge distribution on the Sn atom upon complexation, quadrupole splitting results varied widely, however, when the parent organotin compound was wholly symmetric (SnCl 4 and SnPPh 4 ), the complexes also tended to show quadrupole splitting values approaching zero. (author)

Nuclear weapons complex

International Nuclear Information System (INIS)

Rezendes, V.S.

1992-04-01

In addition to long-standing safety and environmental problems plaguing the nuclear weapons complex, this paper reports that the Department of Energy (DOE) faces a major new challenge-how to reconfigure the weapons complex to meet the nation's defense needs in the 21st century. Key decisions still need to be made about the size of the complex; where, if necessary, to relocate various operations; what technologies to use for new tritium production; and what to do with excess weapons-grade material. The choices confronting DOE and Congress are difficult given the conflicting demands for limited resources

The Orion complex

International Nuclear Information System (INIS)

Goudis, C.

1982-01-01

This work deals with some of the most typical complexes of interstellar matter and presents a holistic view of the well studied complexes in Orion, built on information derived from various branches of modern astrophysics. A wealth of published data is presented in the form of photographs, contour maps, diagrams and numerous heavily annotated tables. Chapter 1, which is concerned with the large scale view of the Orion region, outlines the morphology of the area and examines in particular the nature of Barnard's Loop and the associated filamentary structure in addition to the origin of the I Orion OB association. Chapter 2 focuses on the Great Orion Nebula (M42 or NGC 1976) and the small H II region to the north (M43 or NGC 1982). Chapter 3 examines the Orion Complex as a whole, i.e. the H II regions M42 and M43, the associated molecular clouds OMC 1 and OMC 2 and their interrelations. Chapter 4 contains a discussion of the empirical models introduced to attempt to explain certain aspects of this very complex region, and chapter 5 investigates the second prominent H II region and molecular cloud complex, NGC 2024 (Orion B, W12). (Auth.)

Algorithmic Relative Complexity

Directory of Open Access Journals (Sweden)

Daniele Cerra

2011-04-01

Full Text Available Information content and compression are tightly related concepts that can be addressed through both classical and algorithmic information theories, on the basis of Shannon entropy and Kolmogorov complexity, respectively. The definition of several entities in Kolmogorov’s framework relies upon ideas from classical information theory, and these two approaches share many common traits. In this work, we expand the relations between these two frameworks by introducing algorithmic cross-complexity and relative complexity, counterparts of the cross-entropy and relative entropy (or Kullback-Leibler divergence found in Shannon’s framework. We define the cross-complexity of an object x with respect to another object y as the amount of computational resources needed to specify x in terms of y, and the complexity of x related to y as the compression power which is lost when adopting such a description for x, compared to the shortest representation of x. Properties of analogous quantities in classical information theory hold for these new concepts. As these notions are incomputable, a suitable approximation based upon data compression is derived to enable the application to real data, yielding a divergence measure applicable to any pair of strings. Example applications are outlined, involving authorship attribution and satellite image classification, as well as a comparison to similar established techniques.

Embracing uncertainty, managing complexity: applying complexity thinking principles to transformation efforts in healthcare systems.

Science.gov (United States)

Khan, Sobia; Vandermorris, Ashley; Shepherd, John; Begun, James W; Lanham, Holly Jordan; Uhl-Bien, Mary; Berta, Whitney

2018-03-21

Complexity thinking is increasingly being embraced in healthcare, which is often described as a complex adaptive system (CAS). Applying CAS to healthcare as an explanatory model for understanding the nature of the system, and to stimulate changes and transformations within the system, is valuable. A seminar series on systems and complexity thinking hosted at the University of Toronto in 2016 offered a number of insights on applications of CAS perspectives to healthcare that we explore here. We synthesized topics from this series into a set of six insights on how complexity thinking fosters a deeper understanding of accepted ideas in healthcare, applications of CAS to actors within the system, and paradoxes in applications of complexity thinking that may require further debate: 1) a complexity lens helps us better understand the nebulous term "context"; 2) concepts of CAS may be applied differently when actors are cognizant of the system in which they operate; 3) actor responses to uncertainty within a CAS is a mechanism for emergent and intentional adaptation; 4) acknowledging complexity supports patient-centred intersectional approaches to patient care; 5) complexity perspectives can support ways that leaders manage change (and transformation) in healthcare; and 6) complexity demands different ways of implementing ideas and assessing the system. To enhance our exploration of key insights, we augmented the knowledge gleaned from the series with key articles on complexity in the literature. Ultimately, complexity thinking acknowledges the "messiness" that we seek to control in healthcare and encourages us to embrace it. This means seeing challenges as opportunities for adaptation, stimulating innovative solutions to ensure positive adaptation, leveraging the social system to enable ideas to emerge and spread across the system, and even more important, acknowledging that these adaptive actions are part of system behaviour just as much as periods of stability are. By

Complexity in practice: understanding primary care as a complex adaptive system

Directory of Open Access Journals (Sweden)

Beverley Ellis

2010-06-01

Conclusions The results are real-world exemplars of the emergent properties of complex adaptive systems. Improving clinical governance in primary care requires both complex social interactions and underpinning informatics. The socio-technical lessons learned from this research should inform future management approaches.

Shapes of interacting RNA complexes

DEFF Research Database (Denmark)

Fu, Benjamin Mingming; Reidys, Christian

2014-01-01

Shapes of interacting RNA complexes are studied using a filtration via their topological genus. A shape of an RNA complex is obtained by (iteratively) collapsing stacks and eliminating hairpin loops.This shape-projection preserves the topological core of the RNA complex and for fixed topological...... genus there are only finitely many such shapes. Our main result is a new bijection that relates the shapes of RNA complexes with shapes of RNA structures. This allows to compute the shape polynomial of RNA complexes via the shape polynomial of RNA structures. We furthermore present a linear time uniform...... sampling algorithm for shapes of RNA complexes of fixed topological genus....

Technetium-aspirin molecule complexes

International Nuclear Information System (INIS)

El-Shahawy, A.S.; Mahfouz, R.M.; Aly, A.A.M.; El-Zohry, M.

1993-01-01

Technetium-aspirin and technetium-aspirin-like molecule complexes were prepared. The structure of N-acetylanthranilic acid (NAA) has been decided through CNDO calculations. The ionization potential and electron affinity of the NAA molecule as well as the charge densities were calculated. The electronic absorption spectra of Tc(V)-Asp and Tc(V)-ATS complexes have two characteristic absorption bands at 450 and 600 nm, but the Tc(V)-NAA spectrum has one characteristic band at 450 nm. As a comparative study, Mo-ATS complex was prepared and its electronic absorption spectrum is comparable with the Tc-ATS complex spectrum. (author)

Tb3O2Cl[SeO3]2 and Tb5O4Cl3[SeO3]2: Oxide Chloride Oxoselenates(IV) of Trivalent Terbium with ''Lone-Pair'' Channel or Layer Structures

International Nuclear Information System (INIS)

Wontcheu, Joseph; Schleid, Thomas

2005-01-01

Orthorhombic Tb 3 O 2 Cl[SeO 3 ] 2 (Pnma; a = 535.16(4), b = 1530.51(9), c = 1081.72(7) pm; Z = 4) is formed by reacting a stoichiometric mixture of Tb 4 O 7 , Tb, TbCl 3 , and SeO 2 in a suitable molar ratio (12: 8: 7: 42) within seven days in an evacuated sealed silica tube at 850 C. The needle-shaped, colourless single crystals (light, water and air stable) exhibit one-dimensional strands [(Tb1) 3/3 (Tb2) 2/1 O 4/2 ] 5+ [O 2 Tb 3 ] 5+ along [100] formed by two parallel chains [OTb 4/2 ] 4+ of trans-edge connected [OTb 4 ] 10+ tetrahedra (d(O-Tb) = 220 - 231 pm) which share an extra edge per chain link. The crystal structure contains two crystallographically different Tb 3+ cations: Tb1 is coordinated as bicapped trigonal prism, while Tb2 resides in square antiprismatic coordination. The Se 4+ coordination is best described as Ψ 1 tetrahedral ([SeO 3 E] 2- ; E: non-binding electron pair). The non-binding ''lone-pair'' electrons of four [SeO 3 ] 2- groups and two Cl - anions form pseudo-hexagonal empty channels along [100] between four cationic double chains. Tb 5 O 4 Cl 3 [SeO 3 ] 2 was prepared likewise as plate-like, colourless single crystals by solid-state reaction of an admixture of Tb 4 O 7 , Tb, TbOCl, TbCl 3 , and SeO 2 (molar ratio: 9: 6: 21: 7: 28) in an evacuated sealed silica tube during seven days at 850 C. This compound crystallizes in the monoclinic system (C2/m; a = 1229.13(9), b = 546.17(4), c = 978.79(7) pm, β = 90.485(6) ; Z = 2) and contains three crystallographically different Tb 3+ cations in seven- and eightfold coordination of O 2- and Cl - anions, respectively. The crystal structure of Tb 5 O 4 Cl 3 [SeO 3 ] 2 is layered and built up of corrugated terbium-oxygen sheets [O 4 Tb 5 ] 7+ formed by edge- and vertex-shared [OTb 4 ] 10+ tetrahedra (d(O-Tb) = 226-232 pm) spreading parallel (001). The structure is strongly related to the ''lone-pair'' channel structures of Tb 2 O[SeO 3 ] 2 and Tb 3 O 2 Cl[SeO 3 ] 2 , where single ([OTb 2 ] 4

The pervasive reach of resource-bounded Kolmogorov complexity in computational complexity theory

Czech Academy of Sciences Publication Activity Database

Allender, E.; Koucký, Michal; Ronneburger, D.; Roy, S.

2011-01-01

Roč. 77, č. 1 (2011), s. 14-40 ISSN 0022-0000 R&D Projects: GA ČR GAP202/10/0854; GA MŠk(CZ) 1M0545; GA AV ČR IAA100190902 Institutional research plan: CEZ:AV0Z10190503 Keywords : Circuit complexity * Distinguishing complexity * FewEXP * Formula size * Kolmogorov complexity Subject RIV: BA - General Mathematics Impact factor: 1.157, year: 2011 http://www.sciencedirect.com/science/article/pii/S0022000010000887

Spectral simplicity of apparent complexity. II. Exact complexities and complexity spectra

Science.gov (United States)

Riechers, Paul M.; Crutchfield, James P.

2018-03-01

The meromorphic functional calculus developed in Part I overcomes the nondiagonalizability of linear operators that arises often in the temporal evolution of complex systems and is generic to the metadynamics of predicting their behavior. Using the resulting spectral decomposition, we derive closed-form expressions for correlation functions, finite-length Shannon entropy-rate approximates, asymptotic entropy rate, excess entropy, transient information, transient and asymptotic state uncertainties, and synchronization information of stochastic processes generated by finite-state hidden Markov models. This introduces analytical tractability to investigating information processing in discrete-event stochastic processes, symbolic dynamics, and chaotic dynamical systems. Comparisons reveal mathematical similarities between complexity measures originally thought to capture distinct informational and computational properties. We also introduce a new kind of spectral analysis via coronal spectrograms and the frequency-dependent spectra of past-future mutual information. We analyze a number of examples to illustrate the methods, emphasizing processes with multivariate dependencies beyond pairwise correlation. This includes spectral decomposition calculations for one representative example in full detail.

Complexity of formation in holography

International Nuclear Information System (INIS)

Chapman, Shira; Marrochio, Hugo; Myers, Robert C.

2017-01-01

It was recently conjectured that the quantum complexity of a holographic boundary state can be computed by evaluating the gravitational action on a bulk region known as the Wheeler-DeWitt patch. We apply this complexity=action duality to evaluate the ‘complexity of formation’ (DOI: 10.1103/PhysRevLett.116.191301; 10.1103/PhysRevD.93.086006), i.e. the additional complexity arising in preparing the entangled thermofield double state with two copies of the boundary CFT compared to preparing the individual vacuum states of the two copies. We find that for boundary dimensions d>2, the difference in the complexities grows linearly with the thermal entropy at high temperatures. For the special case d=2, the complexity of formation is a fixed constant, independent of the temperature. We compare these results to those found using the complexity=volume duality.

Complexity of formation in holography

Energy Technology Data Exchange (ETDEWEB)

Chapman, Shira [Perimeter Institute for Theoretical Physics,Waterloo, ON N2L 2Y5 (Canada); Marrochio, Hugo [Perimeter Institute for Theoretical Physics,Waterloo, ON N2L 2Y5 (Canada); Department of Physics & Astronomy and Guelph-Waterloo Physics Institute,University of Waterloo, Waterloo, ON N2L 3G1 (Canada); Myers, Robert C. [Perimeter Institute for Theoretical Physics,Waterloo, ON N2L 2Y5 (Canada)

2017-01-16

It was recently conjectured that the quantum complexity of a holographic boundary state can be computed by evaluating the gravitational action on a bulk region known as the Wheeler-DeWitt patch. We apply this complexity=action duality to evaluate the ‘complexity of formation’ (DOI: 10.1103/PhysRevLett.116.191301; 10.1103/PhysRevD.93.086006), i.e. the additional complexity arising in preparing the entangled thermofield double state with two copies of the boundary CFT compared to preparing the individual vacuum states of the two copies. We find that for boundary dimensions d>2, the difference in the complexities grows linearly with the thermal entropy at high temperatures. For the special case d=2, the complexity of formation is a fixed constant, independent of the temperature. We compare these results to those found using the complexity=volume duality.

Lanthanide complexes with pivaloylacetone

International Nuclear Information System (INIS)

Eliseeva, S.V.; Chugarov, N.V.; Kuz'mina, N.P.; Martynenko, L.I.; Nichiporuk, R.V.; Ivanov, S.A.

2003-01-01

Complexes Ln(pa) 3 ·2H 2 O (Ln=La, Gd, Lu, Hpa - pivaloylacetone) are synthesized and investigated by the methods of element, IR spectroscopic and thermal analyses. Behaviour of the complexes during heating in vacuum is compared with such one for acetylacetonates and dipivaloylmethanates. Structure of the complexes in solution is studied by 1 H NMR and MALDI-MS [ru

Complexity Control of Fast Motion Estimation in H.264/MPEG-4 AVC with Rate-Distortion-Complexity optimization

DEFF Research Database (Denmark)

Wu, Mo; Forchhammer, Søren; Aghito, Shankar Manuel

2007-01-01

A complexity control algorithm for H.264 advanced video coding is proposed. The algorithm can control the complexity of integer inter motion estimation for a given target complexity. The Rate-Distortion-Complexity performance is improved by a complexity prediction model, simple analysis of the pa...... statistics and a control scheme. The algorithm also works well for scene change condition. Test results for coding interlaced video (720x576 PAL) are reported.......A complexity control algorithm for H.264 advanced video coding is proposed. The algorithm can control the complexity of integer inter motion estimation for a given target complexity. The Rate-Distortion-Complexity performance is improved by a complexity prediction model, simple analysis of the past...

Aryldiazo complexes. Syntheses and reactions of new complexes of osmium and ruthenium

International Nuclear Information System (INIS)

Haymore, B.L.; Ibers, J.A.

1975-01-01

Aryldiazo complexes, [M(CO) 2 (NNPh)(PPh 3 ) 2 ][PF 6 ](M = Os, Ru; Ph = C 6 H 5 ), were prepared by allowing diazonium salts to react with M(CO) 3 (PPh 3 ) 2 . Infrared spectra of the Ru complex suggest the presence of two isomers both in solution and in the solid state. These complexes react with a variety of coordinating anions (X - ), to form MX(CO) 2 (NNPh)(PPh 3 ) 2 . The osmium derivatives have ν(NN) near 1455 cm -1 , which is the lowest value yet reported for a nonbridging aryldiazo ligand. The first aryldiazo--hydrido complexes, MH(CO) 2 (NNPh)(PPh 3 ) 2 and MH(CO)(NNPh)(PPh 3 ) 2 , were prepared by deprotonation of the respective phenyldiazene complexes, MH(CO) 2 (HNNPh)(PPh 3 ) 2 + and MH(CO)(HNNPh)(PPh 3 ) 3 + . The compound OsCl 3 (NNPh)(PPh 3 ) 2 was also prepared. A large number of the foregoing complexes were synthesized with selective 2 H and 15 N labels. Infrared and NMR spectra show MX(CO) 2 (NNPh)(PPh 3 ) 2 and the analogous hydrido complex to be pseudooctahedral with trans phosphine ligands, cis carbonyl ligands, and a doubly bent phenyldiazenido (NNPh - ) ligand. Similarly, MH(CO)(NNPh)(PPh 3 ) 2 possesses a trigonal-bipyramidal geometry with trans phosphine ligands and an equatorial, singly bent phenyldiazoniumato (NNPh + ) ligand. Isotopic substitution of the diazo ligand shows that ν(NN) is often vibrationally coupled with phenyl vibrational modes and that two or three bands sometimes shift upon 15 N substitution. Vibrational coupling was also observed in the higher energy region (1850 to 1900 cm -1 ) in the compound RuCl 3 (NNC 6 D 5 )(PPh 3 ) 2 . The wide range in the values of ν(NN), RuCl 3 (NNPh)(PPh 3 ) 2 (1882 cm -1 ) vs. RuCl(CO) 2 (NNPh)(PPh 3 ) 2 (1462 cm -1 ), indicates that the N--N stretching frequencies are sensitive to the electronic and steric environment of the diazo ligand. The aryldiazo complexes are compared with analogous, isoelectronic nitrosyl complexes of Os and Ru

Visual Short-Term Memory Complexity

DEFF Research Database (Denmark)

Sørensen, Thomas Alrik

of objective complexity, it seems that subjective complexity - which is dependent on the familiarity of the stimulus - plays a more important role than the objective visual complexity of the objects stored. In two studies, we explored how familiarity influences the capacity of VSTM. 1) In children learning...... and Cavanagh (2004) have raised the question that the capacity of VSTM is dependent on visual complexity rather than the number of objects. We hypothesise that VSTM capacity is dependent on both the objective and subjective complexity of visual stimuli. Contrary to Alvarez and Cavanagh, who argue for the role...... for letters and pictures remained similar. Our results indicate that VSTM capacity for familiar items is larger irrespective of visual complexity....

Complexity: Outline of the NWO strategic theme Dynamics of complex systems

NARCIS (Netherlands)

Burgers, G.; Doelman, A.; Frenken, K.; Hogeweg, P.; Hommes, C.; van der Maas, H.; Mulder, B.; Stam, K.; van Steen, M.; Zandee, L.

2008-01-01

Dynamics of complex systems is one of the program 5 themes in the NWO (Netherlands Organisation for Scientific Research) strategy for the years 2007-2011. The ambition of the current proposal is to initiate integrated activities in the field of complex systems within the Netherlands, to provide

Complexity : outline of the NWO strategic theme dynamics of complex systems

NARCIS (Netherlands)

Burgers, G.; Doelman, A.; Frenken, K.; Hogeweg, P.; Hommes, C.; Maas, van der H.; Mulder, B.; Stam, K.; Steen, van M.; Zandee, L.

2008-01-01

Dynamics of complex systems is one of the program 5 themes in the NWO (Netherlands Organisation for Scientific Research) strategy for the years 2007-2011. The ambition of the current proposal is to initiate integrated activities in the field of complex systems within the Netherlands, to provide

Coopetition and Complexity : Exploring a Coopetitive Relationship with Complexity

OpenAIRE

Wennberg, Andreas; Persson, Emil

2011-01-01

Cooperation have in previous research been seen as a negative impact on competition and  vice versa. This thesis is building on a concept called coopetition in which cooperation and  competition is studied simultaneously. Coopetition have been studied in terms of the level of  cooperation and competition. However, we found a possible link between coopetition and  complexity in previous literature. Thus, the purpose of this study is to explore whether  complexity can develop an understanding f...

Complexity and Control: Towards a Rigorous Behavioral Theory of Complex Dynamical Systems

Science.gov (United States)

Ivancevic, Vladimir G.; Reid, Darryn J.

We introduce our motive for writing this book on complexity and control with a popular "complexity myth," which seems to be quite wide spread among chaos and complexity theory fashionistas: quote>Low-dimensional systems usually exhibit complex behaviours (which we know fromMay's studies of the Logisticmap), while high-dimensional systems usually exhibit simple behaviours (which we know from synchronisation studies of the Kuramoto model)...quote> We admit that this naive view on complex (e.g., human) systems versus simple (e.g., physical) systems might seem compelling to various technocratic managers and politicians; indeed, the idea makes for appealing sound-bites. However, it is enough to see both in the equations and computer simulations of pendula of various degree - (i) a single pendulum, (ii) a double pendulum, and (iii) a triple pendulum - that this popular myth is plain nonsense. The only thing that we can learn from it is what every tyrant already knows: by using force as a strong means of control, it is possible to effectively synchronise even hundreds of millions of people, at least for a while.

Group 4 Metalloporphyrin diolato Complexes and Catalytic Application of Metalloporphyrins and Related Transition Metal Complexes

Energy Technology Data Exchange (ETDEWEB)

Du, Guodong [Iowa State Univ., Ames, IA (United States)

2003-01-01

In this work, the first examples of group 4 metalloporphyrin 1,2-diolato complexes were synthesized through a number of strategies. In general, treatment of imido metalloporphyrin complexes, (TTP)M=NR, (M = Ti, Zr, Hf), with vicinal diols led to the formation of a series of diolato complexes. Alternatively, the chelating pinacolate complexes could be prepared by metathesis of (TTP)MCl₂ (M = Ti, Hf) with disodium pinacolate. These complexes were found to undergo C-C cleavage reactions to produce organic carbonyl compounds. For titanium porphyrins, treatment of a titanium(II) alkyne adduct, (TTP)Ti(η²-PhC≡CPh), with aromatic aldehydes or aryl ketones resulted in reductive coupling of the carbonyl groups to produce the corresponding diolato complexes. Aliphatic aldehydes or ketones were not reactive towards (TTP)Ti(η²-PhC≡CPh). However, these carbonyl compounds could be incorporated into a diolato complex on reaction with a reactive precursor, (TTP)Ti[O(Ph)₂C(Ph)₂O] to provide unsymmetrical diolato complexes via cross coupling reactions. In addition, an enediolato complex (TTP)Ti(OCPhCPhO) was obtained from the reaction of (TTP)Ti(η²-PhC≡CPh) with benzoin. Titanium porphyrin diolato complexes were found to be intermediates in the (TTP)Ti=O-catalyzed cleavage reactions of vicinal diols, in which atmospheric oxygen was the oxidant. Furthermore, (TTP)Ti=O was capable of catalyzing the oxidation of benzyl alcohol and α-hydroxy ketones to benzaldehyde and α-diketones, respectively. Other high valent metalloporphyrin complexes also can catalyze the oxidative diol cleavage and the benzyl alcohol oxidation reactions with dioxygen. A comparison of Ti(IV) and Sn(IV) porphyrin chemistry was undertaken. While chelated diolato complexes were invariably obtained for titanium porphyrins on treatment with 1,2-diols, the reaction of vicinal diols with tin porphyrins gave a number of products, including mono

Thinking in complexity the complex dynamics of matter, mind, and mankind

CERN Document Server

Mainzer, Klaus

1994-01-01

The theory of nonlinear complex systems has become a successful and widely used problem-solving approach in the natural sciences - from laser physics, quantum chaos and meteorology to molecular modeling in chemistry and computer simulations of cell growth in biology In recent times it has been recognized that many of the social, ecological and political problems of mankind are also of a global, complex and nonlinear nature And one of the most exciting topics of present scientific and public interest is the idea that even the human mind is governed largely by the nonlinear dynamics of complex systems In this wide-ranging but concise treatment Prof Mainzer discusses, in nontechnical language, the common framework behind these endeavours Special emphasis is given to the evolution of new structures in natural and cultural systems and it is seen clearly how the new integrative approach of complexity theory can give new insights that were not available using traditional reductionistic methods

Clearing the complexity: immune complexes and their treatment in lupus nephritis

Directory of Open Access Journals (Sweden)

Catherine Toong

2011-01-01

Full Text Available Catherine Toong1, Stephen Adelstein1, Tri Giang Phan21Department of Clinical Immunology, Royal Prince Alfred Hospital, Missenden Rd, Camperdown, NSW, Australia; 2Immunology Program, Garvan Institute of Medical Research and St. Vincent’s Clinical School, University of New South Wales, Darlinghurst, NSW, AustraliaAbstract: Systemic lupus erythematosus (SLE is a classic antibody-mediated systemic autoimmune disease characterised by the development of autoantibodies to ubiquitous self-antigens (such as antinuclear antibodies and antidouble-stranded DNA antibodies and widespread deposition of immune complexes in affected tissues. Deposition of immune complexes in the kidney results in glomerular damage and occurs in all forms of lupus nephritis. The development of nephritis carries a poor prognosis and high risk of developing end-stage renal failure despite recent therapeutic advances. Here we review the role of DNA-anti-DNA immune complexes in the pathogenesis of lupus nephritis and possible new treatment strategies aimed at their control.Keywords: immune complex, systemic lupus erythematosus, nephritis, therapy

Enhancing molecular logic through modulation of temporal and spatial constraints with quantum dot-based systems that use fluorescent (Förster) resonance energy transfer

Science.gov (United States)

Claussen, Jonathan C.; Algar, W. Russ; Hildebrandt, Niko; Susumu, Kimihiro; Ancona, Mario G.; Medintz, Igor L.

2013-10-01

Luminescent semiconductor nanocrystals or quantum dots (QDs) contain favorable photonic properties (e.g., resistance to photobleaching, size-tunable PL, and large effective Stokes shifts) that make them well-suited for fluorescence (Förster) resonance energy transfer (FRET) based applications including monitoring proteolytic activity, elucidating the effects of nanoparticles-mediated drug delivery, and analyzing the spatial and temporal dynamics of cellular biochemical processes. Herein, we demonstrate how unique considerations of temporal and spatial constraints can be used in conjunction with QD-FRET systems to open up new avenues of scientific discovery in information processing and molecular logic circuitry. For example, by conjugating both long lifetime luminescent terbium(III) complexes (Tb) and fluorescent dyes (A647) to a single QD, we can create multiple FRET lanes that change temporally as the QD acts as both an acceptor and donor at distinct time intervals. Such temporal FRET modulation creates multi-step FRET cascades that produce a wealth of unique photoluminescence (PL) spectra that are well-suited for the construction of a photonic alphabet and photonic logic circuits. These research advances in bio-based molecular logic open the door to future applications including multiplexed biosensing and drug delivery for disease diagnostics and treatment.

Subgroup complexes

CERN Document Server

Smith, Stephen D

2011-01-01

This book is intended as an overview of a research area that combines geometries for groups (such as Tits buildings and generalizations), topological aspects of simplicial complexes from p-subgroups of a group (in the spirit of Brown, Quillen, and Webb), and combinatorics of partially ordered sets. The material is intended to serve as an advanced graduate-level text and partly as a general reference on the research area. The treatment offers optional tracks for the reader interested in buildings, geometries for sporadic simple groups, and G-equivariant equivalences and homology for subgroup complexes.

Adaptive control for a class of nonlinear complex dynamical systems with uncertain complex parameters and perturbations.

Directory of Open Access Journals (Sweden)

Jian Liu

Full Text Available In this paper, adaptive control is extended from real space to complex space, resulting in a new control scheme for a class of n-dimensional time-dependent strict-feedback complex-variable chaotic (hyperchaotic systems (CVCSs in the presence of uncertain complex parameters and perturbations, which has not been previously reported in the literature. In detail, we have developed a unified framework for designing the adaptive complex scalar controller to ensure this type of CVCSs asymptotically stable and for selecting complex update laws to estimate unknown complex parameters. In particular, combining Lyapunov functions dependent on complex-valued vectors and back-stepping technique, sufficient criteria on stabilization of CVCSs are derived in the sense of Wirtinger calculus in complex space. Finally, numerical simulation is presented to validate our theoretical results.

Adaptive control for a class of nonlinear complex dynamical systems with uncertain complex parameters and perturbations.

Science.gov (United States)

Liu, Jian; Liu, Kexin; Liu, Shutang

2017-01-01

In this paper, adaptive control is extended from real space to complex space, resulting in a new control scheme for a class of n-dimensional time-dependent strict-feedback complex-variable chaotic (hyperchaotic) systems (CVCSs) in the presence of uncertain complex parameters and perturbations, which has not been previously reported in the literature. In detail, we have developed a unified framework for designing the adaptive complex scalar controller to ensure this type of CVCSs asymptotically stable and for selecting complex update laws to estimate unknown complex parameters. In particular, combining Lyapunov functions dependent on complex-valued vectors and back-stepping technique, sufficient criteria on stabilization of CVCSs are derived in the sense of Wirtinger calculus in complex space. Finally, numerical simulation is presented to validate our theoretical results.

Complexity a very short introduction

CERN Document Server

Holland, John H

2014-01-01

The importance of complexity is well-captured by Hawking's comment: "Complexity is the science of the 21st century". From the movement of flocks of birds to the Internet, environmental sustainability, and market regulation, the study and understanding of complex non-linear systems has become highly influential over the last 30 years. In this Very Short Introduction, one of the leading figures in the field, John Holland, introduces the key elements and conceptual framework of complexity. From complex physical systems such as fluid flow and the difficulties of predicting weather, to complex adaptive systems such as the highly diverse and interdependent ecosystems of rainforests, he combines simple, well-known examples - Adam Smith's pin factory, Darwin's comet orchid, and Simon's 'watchmaker' - with an account of the approaches, involving agents and urn models, taken by complexity theory. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost eve...

Quantifying Complexity in Quantum Phase Transitions via Mutual Information Complex Networks.

Science.gov (United States)

Valdez, Marc Andrew; Jaschke, Daniel; Vargas, David L; Carr, Lincoln D

2017-12-01

We quantify the emergent complexity of quantum states near quantum critical points on regular 1D lattices, via complex network measures based on quantum mutual information as the adjacency matrix, in direct analogy to quantifying the complexity of electroencephalogram or functional magnetic resonance imaging measurements of the brain. Using matrix product state methods, we show that network density, clustering, disparity, and Pearson's correlation obtain the critical point for both quantum Ising and Bose-Hubbard models to a high degree of accuracy in finite-size scaling for three classes of quantum phase transitions, Z_{2}, mean field superfluid to Mott insulator, and a Berzinskii-Kosterlitz-Thouless crossover.

Quantifying Complexity in Quantum Phase Transitions via Mutual Information Complex Networks

Science.gov (United States)

Valdez, Marc Andrew; Jaschke, Daniel; Vargas, David L.; Carr, Lincoln D.

2017-12-01

We quantify the emergent complexity of quantum states near quantum critical points on regular 1D lattices, via complex network measures based on quantum mutual information as the adjacency matrix, in direct analogy to quantifying the complexity of electroencephalogram or functional magnetic resonance imaging measurements of the brain. Using matrix product state methods, we show that network density, clustering, disparity, and Pearson's correlation obtain the critical point for both quantum Ising and Bose-Hubbard models to a high degree of accuracy in finite-size scaling for three classes of quantum phase transitions, Z2, mean field superfluid to Mott insulator, and a Berzinskii-Kosterlitz-Thouless crossover.

Innovation in a complex environment

Directory of Open Access Journals (Sweden)

René Pellissier

2012-11-01

Objectives: The study objectives were, firstly, to establish the determinants for complexity and how these can be addressed from a design point of view in order to ensure innovation success and, secondly, to determine how this changes innovation forms and applications. Method: Two approaches were offered to deal with a complex environment – one allowing for complexity for organisational innovation and the other introducing reductionism to minimise complexity. These approaches were examined in a qualitative study involving case studies, open-ended interviews and content analysis between seven developing economy (South African organisations and seven developed economy (US organisations. Results: This study presented a proposed framework for (organisational innovation in a complex environment versus a framework that minimises complexity. The comparative organisational analysis demonstrated the importance of initiating organisational innovation to address internal and external complexity, with the focus being on the leadership actions, their selected operating models and resultant organisational innovations designs, rather than on technological innovations. Conclusion: This study cautioned the preference for technological innovation within organisations and suggested alternative innovation forms (such as organisational and management innovation be used to remain competitive in a complex environment.

COMPLEX PROMOTIONSIN RETAIL

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O. Yusupova

2015-10-01

Full Text Available Complex promotions used by retailers introduce to the consumers several rules that must be satisfied in order to get some benefits and usually refer to multiple products (e.g. “buy two, get one free”. Rules of complex promotions can be quite sophisticated and complicated themselves. Since diversity of complex promotions limited only by marketers’ imagination we can observe broad variety of promotions’ rules and representa¬tions of those rules in retailers’ commercials. Such diversification makes no good for fellow scientist who’s trying to sort all type of promotions into the neatly organized classification. Although we can simple add every single set of rules offered by retailers as a separate form of sales promotion it seems not to be the best way of dealing with such a problem. The better way is to realize that mechanisms underlying that variety of promotions are basically the same, namely changes in demand or quantity demanded. Those two concepts alone provide powerful insight into classification of complex promotions and allow us to comprehend the variety of promotions offered by marketers nowadays.

Nuclear weapons complex

International Nuclear Information System (INIS)

Peach, J.D.

1991-02-01

In this paper, GAO provides its views on DOE's January 1991 Nuclear Weapons Complex Reconfiguration Study. GAO believes that DOE's new reconfiguration study provides a starting point for reaching agreement on solutions to many of the complex's problems. Key decisions still need to be made about the size of the complex, where to relocate plutonium operations, what technologies should be used for new tritium production, and what to do with excess plutonium. The total cost for reconfiguring and modernizing is still uncertain and some management issues remain unresolved. Congress faces a difficult task in making these decisions given the conflicting demands for scare resources in a time of growing budget deficits and war in the Persian Gulf

The SEA complex – the beginning

Directory of Open Access Journals (Sweden)

Dokudovskaya S. S.

2012-07-01

Full Text Available The presence of distinctive internal membrane compartments, dynamically connected via selective transport pathways, is a hallmark of eukaryotic cells. Many of the proteins required for formation and maintenance of these compartments share an evolutionary history. We have recently identified a new conserved protein complex – the SEA complex – that possesses proteins with structural characteristics similar to the membrane coating complexes such as the nuclear pore complex (NPC, the COPII vesicle coating complex and HOPS/CORVET tethering complexes. The SEA complex in yeast is dynamically associated to the vacuole. The data on the function of the SEA complex remain extremely limited. Here we will discuss a possible role of the SEA complex based on the data from genetic assays and a number of functional studies in both yeast and other eukaryotes.

Green fluorescence of terbium ions in lithium fluoroborate glasses ...

Indian Academy of Sciences (India)

tion and solid-state lasers attracted remarkable attention in the last few decades. .... Figure 1. Vis absorption spectrum of 1.0 mol% Tb3+-doped. LBZLFB glass. Figure 2. .... both ions quickly decay non-radiatively to the ground level. The energy ...

Analysis of the fourth spectrum of terbium (Tb IV)

International Nuclear Information System (INIS)

Spector, N.; Sugar, J.

1976-01-01

The low-energy level structure of Tb 3+ has been derived from spectra obtained with a sliding spark light source. The 7 F ground term of the 4f 8 configuration was found as well as all levels of the configurations 4f 7 5d, 6s, and 6p built on the 8 S 7 / 2 core state of 4f 7 . Of the possible 51 lines connecting these levels, 48 were observed. Optimized radial parameters are given for the observed configurations. A value for the ionization energy of 39.37(0.10) eV is derived for Tb 3+

Inelastic scattering of neutrons by spin waves in terbium

DEFF Research Database (Denmark)

Bjerrum Møller, Hans; Houmann, Jens Christian Gylden

1966-01-01

Measurements of spin-wave dispersion relations for magnons propagating in symmetry directions in ferromagnetic Tb; it is first experiment to give detailed information on magnetic excitations in heavy rare earths; Tb was chosen for these measurements because it is one of few rare-earth metals which...... does not have very high thermal-neutron capture cross section, so that inelastic neutron scattering experiments can give satisfactory information on magnon dispersion relations....

Qubit Complexity of Continuous Problems

National Research Council Canada - National Science Library

Papageorgiou, A; Traub, J. F

2005-01-01

.... The authors show how to obtain the classical query complexity for continuous problems. They then establish a simple formula for a lower bound on the qubit complexity in terms of the classical query complexity...

Innovation in a complex environment

Directory of Open Access Journals (Sweden)

René Pellissier

2012-02-01

Full Text Available Background: As our world becomes more global and competitive yet less predictable, the focus seems to be increasingly on looking to innovation activities to remain competitive. Although there is little doubt that a nation’s competitiveness is embedded in its innovativeness, the complex environment should not be ignored. Complexity is not accounted for in balance sheets or reported in reports; it becomes entrenched in every activity in the organisation. Innovation takes many forms and comes in different shapes.Objectives: The study objectives were, firstly, to establish the determinants for complexity and how these can be addressed from a design point of view in order to ensure innovation success and, secondly, to determine how this changes innovation forms and applications.Method: Two approaches were offered to deal with a complex environment – one allowing for complexity for organisational innovation and the other introducing reductionism to minimise complexity. These approaches were examined in a qualitative study involving case studies, open-ended interviews and content analysis between seven developing economy (South African organisations and seven developed economy (US organisations.Results: This study presented a proposed framework for (organisational innovation in a complex environment versus a framework that minimises complexity. The comparative organisational analysis demonstrated the importance of initiating organisational innovation to address internal and external complexity, with the focus being on the leadership actions, their selected operating models and resultant organisational innovations designs, rather than on technological innovations.Conclusion: This study cautioned the preference for technological innovation within organisations and suggested alternative innovation forms (such as organisational and management innovation be used to remain competitive in a complex environment. 

SCAR/WAVE: A complex issue.

Science.gov (United States)

Davidson, Andrew J; Insall, Robert H

2013-11-01

The SCAR/WAVE complex drives the actin polymerisation that underlies protrusion of the front of the cell and thus drives migration. However, it is not understood how the activity of SCAR/WAVE is regulated to generate the infinite range of cellular shape changes observed during cell motility. What are the relative roles of the subunits of the SCAR/WAVE complex? What signaling molecules do they interact with? And how does the complex integrate all this information in order to control the temporal and spatial polymerisation of actin during protrusion formation? Unfortunately, the interdependence of SCAR complex members has made genetic dissection hard. In our recent paper,(1) we describe stabilization of the Dictyostelium SCAR complex by a small fragment of Abi. Here we summarize the main findings and discuss how this approach can help reveal the inner workings of this impenetrable complex.

Complex manifolds

CERN Document Server

Morrow, James

2006-01-01

This book, a revision and organization of lectures given by Kodaira at Stanford University in 1965-66, is an excellent, well-written introduction to the study of abstract complex (analytic) manifolds-a subject that began in the late 1940's and early 1950's. It is largely self-contained, except for some standard results about elliptic partial differential equations, for which complete references are given. -D. C. Spencer, MathSciNet The book under review is the faithful reprint of the original edition of one of the most influential textbooks in modern complex analysis and geometry. The classic

Hypoxia targeting copper complexes

International Nuclear Information System (INIS)

Dearling, J.L.

1998-11-01

The importance and incidence of tumour hypoxia, its measurement and current treatments available, including pharmacological and radiopharmacological methods of targeting hypoxia, are discussed. A variety of in vitro and in vivo methods for imposing hypoxia have been developed and are reviewed. Copper, its chemistry, biochemistry and radiochemistry, the potential for use of copper radionuclides and its use to date in this field is considered with particular reference to the thiosemicarbazones. Their biological activity, metal chelation, in vitro and in vivo studies of their radiocopper complexes and the potential for their use as hypoxia targeting radiopharmaceuticals is described. The reduction of the copper(II) complex to copper(l), its pivotal importance in their biological behaviour, and the potential for manipulation of this to effect hypoxia selectivity are described. An in vitro method for assessing the hypoxia selectivity of radiopharmaceuticals is reported. The rapid deoxygenation and high viability of a mammalian cell culture in this system is discussed and factors which may affect the cellular uptake of a radiopharmaceutical are described. The design, synthesis and complexation with copper and radiocopper of a range of bis(thiosemicarbazones) is reported. Synthesis of these compounds is simple giving high yields of pure products. The characteristics of the radiocopper complexes ( 64 Cu) including lipophilicity and redox activity are reported (reduction potentials in the range -0.314 - -0.590 V). High cellular uptakes of the radiocopper complexes of the ligands, in hypoxic and normoxic EMT6 and CHO320 cells, were observed. Extremes of selectivity are shown ranging from the hypoxia selective 64 Cu(II)ATSM to normoxic cell selective 64 Cu(II)GTS. The selectivities observed are compared with the physico chemical characteristics of the complexes. A good correlation exists between selectivity of the complex and its Cu(II)/Cu(I) reduction potential, with hypoxia

Complex Systems and Dependability

CERN Document Server

Zamojski, Wojciech; Sugier, Jaroslaw

2012-01-01

Typical contemporary complex system is a multifaceted amalgamation of technical, information, organization, software and human (users, administrators and management) resources. Complexity of such a system comes not only from its involved technical and organizational structure but mainly from complexity of information processes that must be implemented in the operational environment (data processing, monitoring, management, etc.). In such case traditional methods of reliability analysis focused mainly on technical level are usually insufficient in performance evaluation and more innovative meth

Complexity Management - A multiple case study analysis on control and reduction of complexity costs

DEFF Research Database (Denmark)

Myrodia, Anna

of products, with features more custom-made to cover individual needs, both regarding characteristics of products and support services. This necessity leads to a considerable increase of the complexity in the company, which affects the product portfolio, production and supply chain, market segments......, IT systems, and business processes. In order to identify and eliminate complexity, several approaches are used, both by researchers and practitioners. The purpose of this thesis is to contribute to the existing knowledge of complexity management theory. This research focuses on the relationship between......Complexity tends to be arguably the biggest challenge of manufacturing companies. The motivation of further studying complexity is a combination between the existing literature and the practical experiences from the industry. Based on the latest trend companies are trying to supply a growing mix...

On dependence of stability of lanthanum complexes with aminopolycarboxylic acids on the complex structure

International Nuclear Information System (INIS)

Poluehktov, N.S.; Meshkova, S.B.; Danilkovich, M.M.; Topilova, Z.M.

1985-01-01

Regularities in changes of stability constants of lanthanum complexes with aminopolycarboxylic acids (APA) versus their structure are studied, The stability of lathanum-APA complexes depends mainly on the number of carboxyl groups in a ligand molecule. At that, the highest stability constant is characteristic of a complex with a ligand, containing 3 nitrogen atoms and 5 carboxyl groups, in the presenoe of which the lanthanum ion coordination sphere gets satupated. The oxyethy group introduction into a ligand molecule also improves the lanthanum complex stability but to a lesser degree than during the introduction of a carboxyl group. The number of nitrogen atoms in a ligand polecule affects insignificantly the complex stability constant value, and the elongation of a chain of CH 2 groups, separating nitrogen atoms, reduces the constant to a -0.6 power

Complex Projective Synchronization in Drive-Response Stochastic Complex Networks by Impulsive Pinning Control

Directory of Open Access Journals (Sweden)

Xuefei Wu

2014-01-01

Full Text Available The complex projective synchronization in drive-response stochastic coupled networks with complex-variable systems is considered. The impulsive pinning control scheme is adopted to achieve complex projective synchronization and several simple and practical sufficient conditions are obtained in a general drive-response network. In addition, the adaptive feedback algorithms are proposed to adjust the control strength. Several numerical simulations are provided to show the effectiveness and feasibility of the proposed methods.

MANAGEMENT OF SPORT COMPLEXES

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Marian STAN

2015-07-01

Full Text Available The actuality of the investigated theme. Nowadays, human evolution, including his intellectual development, proves the fact that especially the creation manpower and the employment was the solution of all life’s ambitions in society. So, the fact is that in reality, man is the most important capital of the society. Also, in an individual’s life, the practice of sport plays a significant role and that’s why the initiation, the launch and the management of sports complexes activity reveal the existence of specific management features that we will identify and explain in the current study. The aim of the research refers to the elaboration of a theoretical base of the management of the sport complexes, to the pointing of the factors that influence the efficient existence and function of a sport complex in our country and to the determination of the responsibilities that have a manager who directs successfully the activity of the sport complexes. The investigation is based on theoretical methods, such as: scientific documentation, analysis, synthesis, comparison and on empirical research methods, like: study of researched literature and observation. The results of the research indicate the fact that the profitability of a sport complex must assure a particular structure to avoid the bankruptcy risk and also, that the administration of the sport complexes activity must keep in view the reliable functions of the contemporaneous management.

COMPLEXITY AND UNIVERSITY

Directory of Open Access Journals (Sweden)

Edna Lemes Martins Pereira

2013-12-01

Full Text Available Economic globalization affects different countries on the globe, has positive effects mainly related to access to communication, which promotes the exchange of ideas, information, products and quality of life. However, extends numerous negative aspects such as marginalization, economic dependencies, political, cultural, scientific, educational accentuate social inequalities and cultural conflicts and territorial. In this article it is a dialogue with authors (Cunha 2009; BARNETT 2005; MORIN 1999, 2006, among others, who understand these changes in society from the contemporary world as conceived as the "Complexity era" or "supercomplexity". To understand and cope with this reality, they propose a paradigm that is able to overcome the fragmentation and reductionism of knowledge and to relate the multiple approaches and visions to meet the complexity of reality. Although this paper presents proposals to the aforementioned authors point to education and the university found in this tangle of interconnected global transformations, given the need to be subject to act in a complex reality that requires critical and self-critical professionals, able to think about their own ability to think, understand and act within this complex context.

Cooperativity of complex salt bridges

OpenAIRE

Gvritishvili, Anzor G.; Gribenko, Alexey V.; Makhatadze, George I.

2008-01-01

The energetic contribution of complex salt bridges, in which one charged residue (anchor residue) forms salt bridges with two or more residues simultaneously, has been suggested to have importance for protein stability. Detailed analysis of the net energetics of complex salt bridge formation using double- and triple-mutant cycle analysis revealed conflicting results. In two cases, it was shown that complex salt bridge formation is cooperative, i.e., the net strength of the complex salt bridge...

Structural, spectroscopic and cytotoxicity studies of TbF{sub 3}@CeF{sub 3} and TbF{sub 3}@CeF{sub 3}@SiO{sub 2} nanocrystals

Energy Technology Data Exchange (ETDEWEB)

Grzyb, Tomasz; Runowski, Marcin [Adam Mickiewicz University, Department of Rare Earths, Faculty of Chemistry (Poland); Dabrowska, Krystyna [Polish Academy of Sciences, Bacteriophage Laboratory, Institute of Immunology and Experimental Therapy (Poland); Giersig, Michael; Lis, Stefan, E-mail: blis@amu.edu.pl [Adam Mickiewicz University, Department of Rare Earths, Faculty of Chemistry (Poland)

2013-10-15

Terbium fluoride nanocrystals, covered by a shell, composed of cerium fluoride were synthesized by a co-precipitation method. Their complex structure was formed spontaneously during the synthesis. The surface of these core/shell nanocrystals was additionally modified by silica. The properties of TbF{sub 3}@CeF{sub 3} and TbF{sub 3}@CeF{sub 3}@SiO{sub 2} nanocrystals, formed in this way, were investigated. Spectroscopic studies showed that the differences between these two groups of products resulted from the presence of the SiO{sub 2} shell. X-ray diffraction patterns confirmed the trigonal crystal structure of TbF{sub 3}@CeF{sub 3} nanocrystals. High resolution transmission electron microscopy in connection with energy-dispersive X-ray spectroscopy showed a complex structure of the formed nanocrystals. Crystallized as small discs, 'the products', with an average diameter around 10 nm, showed an increase in the concentration of Tb{sup 3+} ions from surface to the core of nanocrystals. In addition to photo-physical analyses, cytotoxicity studies were performed on HSkMEC (Human Skin Microvascular Endothelial Cells) and B16F0 mouse melanoma cancer cells. The cytotoxicity of the nanomaterials was neutral for the investigated cells with no toxic or antiproliferative effect in the cell cultures, either for normal or for cancer cells. This fact makes the obtained nanocrystals good candidates for biological applications and further modifications of the SiO{sub 2} shell.Graphical Abstract.

Structural, spectroscopic and cytotoxicity studies of TbF3@CeF3 and TbF3@CeF3@SiO2 nanocrystals

International Nuclear Information System (INIS)

Grzyb, Tomasz; Runowski, Marcin; Dąbrowska, Krystyna; Giersig, Michael; Lis, Stefan

2013-01-01

Terbium fluoride nanocrystals, covered by a shell, composed of cerium fluoride were synthesized by a co-precipitation method. Their complex structure was formed spontaneously during the synthesis. The surface of these core/shell nanocrystals was additionally modified by silica. The properties of TbF 3 @CeF 3 and TbF 3 @CeF 3 @SiO 2 nanocrystals, formed in this way, were investigated. Spectroscopic studies showed that the differences between these two groups of products resulted from the presence of the SiO 2 shell. X-ray diffraction patterns confirmed the trigonal crystal structure of TbF 3 @CeF 3 nanocrystals. High resolution transmission electron microscopy in connection with energy-dispersive X-ray spectroscopy showed a complex structure of the formed nanocrystals. Crystallized as small discs, ‘the products’, with an average diameter around 10 nm, showed an increase in the concentration of Tb 3+ ions from surface to the core of nanocrystals. In addition to photo-physical analyses, cytotoxicity studies were performed on HSkMEC (Human Skin Microvascular Endothelial Cells) and B16F0 mouse melanoma cancer cells. The cytotoxicity of the nanomaterials was neutral for the investigated cells with no toxic or antiproliferative effect in the cell cultures, either for normal or for cancer cells. This fact makes the obtained nanocrystals good candidates for biological applications and further modifications of the SiO 2 shell.Graphical Abstract

Study of complex modes

International Nuclear Information System (INIS)

Pastrnak, J.W.

1986-01-01

This eighteen-month study has been successful in providing the designer and analyst with qualitative guidelines on the occurrence of complex modes in the dynamics of linear structures, and also in developing computer codes for determining quantitatively which vibration modes are complex and to what degree. The presence of complex modes in a test structure has been verified. Finite element analysis of a structure with non-proportional dumping has been performed. A partial differential equation has been formed to eliminate possible modeling errors

Managing complexity insights, concepts, applications

CERN Document Server

Helbing, Dirk

2007-01-01

Each chapter in Managing Complexity focuses on analyzing real-world complex systems and transferring knowledge from the complex-systems sciences to applications in business, industry and society. The interdisciplinary contributions range from markets and production through logistics, traffic control, and critical infrastructures, up to network design, information systems, social conflicts and building consensus. They serve to raise readers' awareness concerning the often counter-intuitive behavior of complex systems and to help them integrate insights gained in complexity research into everyday planning, decision making, strategic optimization, and policy. Intended for a broad readership, the contributions have been kept largely non-technical and address a general, scientifically literate audience involved in corporate, academic, and public institutions.

Complexation of buffer constituents with neutral complexation agents: part II. Practical impact in capillary zone electrophoresis.

Science.gov (United States)

Beneš, Martin; Riesová, Martina; Svobodová, Jana; Tesařová, Eva; Dubský, Pavel; Gaš, Bohuslav

2013-09-17

This article elucidates the practical impact of the complexation of buffer constituents with complexation agents on electrophoretic results, namely, complexation constant determination, system peak development, and proper separation of analytes. Several common buffers, which were selected based on the pH study in Part I of this paper series (Riesová, M.; Svobodová, J.; Tošner, Z.; Beneš, M.; Tesařová, E.; Gaš, B. Anal. Chem., 2013, DOI: 10.1021/ac4013804); e.g., CHES, MES, MOPS, Tricine were used to demonstrate behavior of such complex separation systems. We show that the value of a complexation constant determined in the interacting buffers environment depends not only on the analyte and complexation agent but it is also substantially affected by the type and concentration of buffer constituents. As a result, the complexation parameters determined in the interacting buffers cannot be regarded as thermodynamic ones and may provide misleading information about the strength of complexation of the compound of interest. We also demonstrate that the development of system peaks in interacting buffer systems significantly differs from the behavior known for noncomplexing systems, as the mobility of system peaks depends on the concentration and type of neutral complexation agent. Finally, we show that the use of interacting buffers can totally ruin the results of electrophoretic separation because the buffer properties change as the consequence of the buffer constituents' complexation. As a general conclusion, the interaction of buffer constituents with the complexation agent should always be considered in any method development procedures.

Quantify the complexity of turbulence

Science.gov (United States)

Tao, Xingtian; Wu, Huixuan

2017-11-01

Many researchers have used Reynolds stress, power spectrum and Shannon entropy to characterize a turbulent flow, but few of them have measured the complexity of turbulence. Yet as this study shows, conventional turbulence statistics and Shannon entropy have limits when quantifying the flow complexity. Thus, it is necessary to introduce new complexity measures- such as topology complexity and excess information-to describe turbulence. Our test flow is a classic turbulent cylinder wake at Reynolds number 8100. Along the stream-wise direction, the flow becomes more isotropic and the magnitudes of normal Reynolds stresses decrease monotonically. These seem to indicate the flow dynamics becomes simpler downstream. However, the Shannon entropy keeps increasing along the flow direction and the dynamics seems to be more complex, because the large-scale vortices cascade to small eddies, the flow is less correlated and more unpredictable. In fact, these two contradictory observations partially describe the complexity of a turbulent wake. Our measurements (up to 40 diameters downstream the cylinder) show that the flow's degree-of-complexity actually increases firstly and then becomes a constant (or drops slightly) along the stream-wise direction. University of Kansas General Research Fund.

BRAND program complex

International Nuclear Information System (INIS)

Androsenko, A.A.; Androsenko, P.A.

1983-01-01

A description is given of the structure, input procedure and recording rules of initial data for the BRAND programme complex intended for the Monte Carlo simulation of neutron physics experiments. The BRAND complex ideology is based on non-analogous simulation of the neutron and photon transport process (statistic weights are used, absorption and escape of particles from the considered region is taken into account, shifted readouts from a coordinate part of transition nucleus density are applied, local estimations, etc. are used). The preparation of initial data for three sections is described in detail: general information for Monte Carlo calculation, source definition and data for describing the geometry of the system. The complex is to be processed with the BESM-6 computer, the basic programming lan-- guage is FORTRAN, volume - more than 8000 operators

Identification of a small TAF complex and its role in the assembly of TAF-containing complexes.

Science.gov (United States)

Demény, Màté A; Soutoglou, Evi; Nagy, Zita; Scheer, Elisabeth; Jànoshàzi, Agnes; Richardot, Magalie; Argentini, Manuela; Kessler, Pascal; Tora, Laszlo

2007-03-21

TFIID plays a role in nucleating RNA polymerase II preinitiation complex assembly on protein-coding genes. TFIID is a multisubunit complex comprised of the TATA box binding protein (TBP) and 14 TBP-associated factors (TAFs). Another class of multiprotein transcriptional regulatory complexes having histone acetyl transferase (HAT) activity, and containing TAFs, includes TFTC, STAGA and the PCAF/GCN5 complex. Looking for as yet undiscovered subunits by a proteomic approach, we had identified TAF8 and SPT7L in human TFTC preparations. Subsequently, however, we demonstrated that TAF8 was not a stable component of TFTC, but that it is present in a small TAF complex (SMAT), containing TAF8, TAF10 and SPT7L, that co-purified with TFTC. Thus, TAF8 is a subunit of both TFIID and SMAT. The latter has to be involved in a pathway of complex formation distinct from the other known TAF complexes, since these three histone fold (HF)-containing proteins (TAF8, TAF10 and SPT7L) can never be found together either in TFIID or in STAGA/TFTC HAT complexes. Here we show that TAF8 is absolutely necessary for the integration of TAF10 in a higher order TFIID core complex containing seven TAFs. TAF8 forms a heterodimer with TAF10 through its HF and proline rich domains, and also interacts with SPT7L through its C-terminal region, and the three proteins form a complex in vitro and in vivo. Thus, the TAF8-TAF10 and TAF10-SPT7L HF pairs, and also the SMAT complex, seem to be important regulators of the composition of different TFIID and/or STAGA/TFTC complexes in the nucleus and consequently may play a role in gene regulation.

Complexity science and leadership in healthcare.

Science.gov (United States)

Burns, J P

2001-10-01

The emerging field of complexity science offers an alternative leadership strategy for the chaotic, complex healthcare environment. A survey revealed that healthcare leaders intuitively support principles of complexity science. Leadership that uses complexity principles offers opportunities in the chaotic healthcare environment to focus less on prediction and control and more on fostering relationships and creating conditions in which complex adaptive systems can evolve to produce creative outcomes.

Complex Functions with GeoGebra

Science.gov (United States)

Breda, Ana Maria D'azevedo; Dos Santos, José Manuel Dos Santos

2016-01-01

Complex functions, generally feature some interesting peculiarities, seen as extensions of real functions. The visualization of complex functions properties usually requires the simultaneous visualization of two-dimensional spaces. The multiple Windows of GeoGebra, combined with its ability of algebraic computation with complex numbers, allow the…

Complex DNA structures and structures of DNA complexes

International Nuclear Information System (INIS)

Chazin, W.J.; Carlstroem, G.; Shiow-Meei Chen; Miick, S.; Gomez-Paloma, L.; Smith, J.; Rydzewski, J.

1994-01-01

Complex DNA structures (for example, triplexes, quadruplexes, junctions) and DNA-ligand complexes are more difficult to study by NMR than standard DNA duplexes are because they have high molecular weights, show nonstandard or distorted local conformations, and exhibit large resonance linewidths and severe 1 H spectral overlap. These systems also tend to have limited solubility and may require specialized solution conditions to maintain favorable spectral characteristics, which adds to the spectroscopic difficulties. Furthermore, with more atoms in the system, both assignment and structure calculation become more challenging. In this article, we focus on demonstrating the current status of NMR studies of such systems and the limitations to further progress; we also indicate in what ways isotopic enrichment can be useful

Complex DNA structures and structures of DNA complexes

Energy Technology Data Exchange (ETDEWEB)

Chazin, W.J.; Carlstroem, G.; Shiow-Meei Chen; Miick, S.; Gomez-Paloma, L.; Smith, J.; Rydzewski, J. [Scripps Research Institute, La Jolla, CA (United States)

1994-12-01

Complex DNA structures (for example, triplexes, quadruplexes, junctions) and DNA-ligand complexes are more difficult to study by NMR than standard DNA duplexes are because they have high molecular weights, show nonstandard or distorted local conformations, and exhibit large resonance linewidths and severe {sup 1}H spectral overlap. These systems also tend to have limited solubility and may require specialized solution conditions to maintain favorable spectral characteristics, which adds to the spectroscopic difficulties. Furthermore, with more atoms in the system, both assignment and structure calculation become more challenging. In this article, we focus on demonstrating the current status of NMR studies of such systems and the limitations to further progress; we also indicate in what ways isotopic enrichment can be useful.

Oligocyclopentadienyl transition metal complexes

Energy Technology Data Exchange (ETDEWEB)

de Azevedo, Cristina G.; Vollhardt, K. Peter C.

2002-01-18

Synthesis, characterization, and reactivity studies of oligocyclopentadienyl transition metal complexes, namely those of fulvalene, tercyclopentadienyl, quatercyclopentadienyl, and pentacyclopentadienyl(cyclopentadienyl) are the subject of this account. Thermal-, photo-, and redox chemistries of homo- and heteropolynuclear complexes are described.

Measuring Complexity of SAP Systems

Directory of Open Access Journals (Sweden)

Ilja Holub

2016-10-01

Full Text Available The paper discusses the reasons of complexity rise in ERP system SAP R/3. It proposes a method for measuring complexity of SAP. Based on this method, the computer program in ABAP for measuring complexity of particular SAP implementation is proposed as a tool for keeping ERP complexity under control. The main principle of the measurement method is counting the number of items or relations in the system. The proposed computer program is based on counting of records in organization tables in SAP.

Exotic plant species around Jeongeup Research Complex and RFT industrial complex

International Nuclear Information System (INIS)

Kim, Jin Kyu; Cha, Min Kyoung; Ryu, Tae Ho; Lee, Yun Jong; Kim, Jin Hong

2015-01-01

In Shinjeong-dong of Jeongeup, there are three government-supported research institutes and an RFT industrial complex which is currently being established. Increased human activities can affect flora and fauna as a man-made pressure onto the region. As a baseline study, status of exotic plants was investigated prior to a full operation of the RFT industrial complex. A total of 54 species and 1 variety of naturalized or introduced plants were found in the study area. Among them, three species (Ambrosia artemisifolia var. elatior, Rumex acetocella and Aster pilosus) belong to 'nuisance species', and four species (Phytolacca americana, Iopomoea hederacea, Ereechtites hieracifolia and Rudbeckia laciniata) to ‘monitor species’ designated by the ministry of Environment. Some of naturalized trees and plants were intentionally introduced in this area, while others naturally immigrated. Physalis angulata seems to immigrate in the study area in the form of mixture with animal feeds as its distribution coincided with the transportation route of the animal feeds. Liquidambar styraciflua is amenable to the ecological investigation on the possible expansion of the species to the nearby Naejang National Park as its leave shape and autumn color are very similar to those of maple trees. The number of naturalized plants around the RFT industrial complex will increase with an increase in floating population, in human activities in association with constructions of factories and operations of the complex. The result of this study provides baseline data for assessing the ecological change of the region according to the operation of the RFT industrial complex

Exotic plant species around Jeongeup Research Complex and RFT industrial complex

Energy Technology Data Exchange (ETDEWEB)

Kim, Jin Kyu; Cha, Min Kyoung; Ryu, Tae Ho; Lee, Yun Jong; Kim, Jin Hong [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup(Korea, Republic of)

2015-08-15

In Shinjeong-dong of Jeongeup, there are three government-supported research institutes and an RFT industrial complex which is currently being established. Increased human activities can affect flora and fauna as a man-made pressure onto the region. As a baseline study, status of exotic plants was investigated prior to a full operation of the RFT industrial complex. A total of 54 species and 1 variety of naturalized or introduced plants were found in the study area. Among them, three species (Ambrosia artemisifolia var. elatior, Rumex acetocella and Aster pilosus) belong to 'nuisance species', and four species (Phytolacca americana, Iopomoea hederacea, Ereechtites hieracifolia and Rudbeckia laciniata) to ‘monitor species’ designated by the ministry of Environment. Some of naturalized trees and plants were intentionally introduced in this area, while others naturally immigrated. Physalis angulata seems to immigrate in the study area in the form of mixture with animal feeds as its distribution coincided with the transportation route of the animal feeds. Liquidambar styraciflua is amenable to the ecological investigation on the possible expansion of the species to the nearby Naejang National Park as its leave shape and autumn color are very similar to those of maple trees. The number of naturalized plants around the RFT industrial complex will increase with an increase in floating population, in human activities in association with constructions of factories and operations of the complex. The result of this study provides baseline data for assessing the ecological change of the region according to the operation of the RFT industrial complex.

A Memristor-Based Hyperchaotic Complex Lü System and Its Adaptive Complex Generalized Synchronization

Directory of Open Access Journals (Sweden)

Shibing Wang

2016-02-01

Full Text Available This paper introduces a new memristor-based hyperchaotic complex Lü system (MHCLS and investigates its adaptive complex generalized synchronization (ACGS. Firstly, the complex system is constructed based on a memristor-based hyperchaotic real Lü system, and its properties are analyzed theoretically. Secondly, its dynamical behaviors, including hyperchaos, chaos, transient phenomena, as well as periodic behaviors, are explored numerically by means of bifurcation diagrams, Lyapunov exponents, phase portraits, and time history diagrams. Thirdly, an adaptive controller and a parameter estimator are proposed to realize complex generalized synchronization and parameter identification of two identical MHCLSs with unknown parameters based on Lyapunov stability theory. Finally, the numerical simulation results of ACGS and its applications to secure communication are presented to verify the feasibility and effectiveness of the proposed method.

Complexity of Economical Systems

Directory of Open Access Journals (Sweden)

G. P. Pavlos

2015-01-01

Full Text Available In this study new theoretical concepts are described concerning the interpretation of economical complex dynamics. In addition a summary of an extended algorithm of nonlinear time series analysis is provided which is applied not only in economical time series but also in other physical complex systems (e.g. [22, 24]. In general, Economy is a vast and complicated set of arrangements and actions wherein agents—consumers, firms, banks, investors, government agencies—buy and sell, speculate, trade, oversee, bring products into being, offer services, invest in companies, strategize, explore, forecast, compete, learn, innovate, and adapt. As a result the economic and financial variables such as foreign exchange rates, gross domestic product, interest rates, production, stock market prices and unemployment exhibit large-amplitude and aperiodic fluctuations evident in complex systems. Thus, the Economics can be considered as spatially distributed non-equilibrium complex system, for which new theoretical concepts, such as Tsallis non extensive statistical mechanics and strange dynamics, percolation, nonGaussian, multifractal and multiscale dynamics related to fractional Langevin equations can be used for modeling and understanding of the economical complexity locally or globally.

Complexity and Dynamical Depth

Directory of Open Access Journals (Sweden)

Terrence Deacon

2014-07-01

Full Text Available We argue that a critical difference distinguishing machines from organisms and computers from brains is not complexity in a structural sense, but a difference in dynamical organization that is not well accounted for by current complexity measures. We propose a measure of the complexity of a system that is largely orthogonal to computational, information theoretic, or thermodynamic conceptions of structural complexity. What we call a system’s dynamical depth is a separate dimension of system complexity that measures the degree to which it exhibits discrete levels of nonlinear dynamical organization in which successive levels are distinguished by local entropy reduction and constraint generation. A system with greater dynamical depth than another consists of a greater number of such nested dynamical levels. Thus, a mechanical or linear thermodynamic system has less dynamical depth than an inorganic self-organized system, which has less dynamical depth than a living system. Including an assessment of dynamical depth can provide a more precise and systematic account of the fundamental difference between inorganic systems (low dynamical depth and living systems (high dynamical depth, irrespective of the number of their parts and the causal relations between them.

Synthesis and characterization of magnetic nanoparticles of oxides for dual MnFe2O4 bioseparation, stabilized in fatty acid and the system chitosan - Eu(TTA)3(TPPO)2. Studies on the influence of doping with Gd3+, Tb3+, Ho3+ e Eu3+ in structural and magnetic properties

International Nuclear Information System (INIS)

Kovacs, Thelma Antunes Rodrigues

2014-01-01

This work was synthesized and characterized ferrite magnetic nanoparticles manganese, using the chemical coprecipitation method. By varying the heating time under 98°C (0, 10,20,40,60 3 80 minutes), the molar percentage of doping (1, 3, 5, 7, and 10%), gadolinium, europium, terbium and holmium. Magnetic ferrite nanoparticles and manganese ferrite doped with manganese were synthesized by coprecipitation method starting with chloride solutions of metals (iron (III), manganese (II), europium (III), gadolinium (III), terbium (III) and holmium (III)) and NaOH 5mol.L -1 as precipitating agent. The magnetic nanoparticles were characterized by scanning electron microscopy, infrared spectroscopy, X-ray diffraction, magnetization curves, and thermal analysis. Most of manganese ferrite particles showed superparamagnetic behavior. After the characterization it was found that the samples synthesized manganese ferrite with more than 40 minutes heating time, crystal structure showed the characteristic pattern of the inverted manganese ferrite spinel type. The stabilization of the samples in oleic acid nanoparticles produced with a hydrophobic outer layer and facilitated by coating chitosan biopolymer, since this has a positive charge. Among the doped samples there was no significant change in the magnetic behavior. Several techniques for characterizing these materials have been used such as X-ray diffraction spectrum in the infrared region, magnetization curves and thermal analysis. The resins were tested as magnetic material for the separation of biological materials. In this paper, are used as biological targets separation of bovine serum albumin. (author)

Synthesis and characterization of magnetic nanoparticles of oxides for dual MnFe{sub 2}O{sub 4} bioseparation, stabilized in fatty acid and the system chitosan - Eu(TTA){sub 3}(TPPO){sub 2}. Studies on the influence of doping with Gd{sup 3+}, Tb{sup 3+}, Ho{sup 3+} e Eu{sup 3+} in structural and magnetic properties; Sintese e caracterizacao de nanoparticulas magneticas de oxidos duplos de MnFe{sub 2}O{sub 4} para biosseparacao, estabilizadas em acido graxo e recobertas pelo sistema quitosana - Eu(TTA){sub 3}(TPPO){sub 2}. Estudo da influencia da dopagem com Gd{sup 3+}, Tb{sup 3+}, Ho{sup 3+} e Eu{sup 3+} nas propriedades estruturais e magneticas

Energy Technology Data Exchange (ETDEWEB)

Kovacs, Thelma Antunes Rodrigues

2014-07-01

This work was synthesized and characterized ferrite magnetic nanoparticles manganese, using the chemical coprecipitation method. By varying the heating time under 98°C (0, 10,20,40,60 3 80 minutes), the molar percentage of doping (1, 3, 5, 7, and 10%), gadolinium, europium, terbium and holmium. Magnetic ferrite nanoparticles and manganese ferrite doped with manganese were synthesized by coprecipitation method starting with chloride solutions of metals (iron (III), manganese (II), europium (III), gadolinium (III), terbium (III) and holmium (III)) and NaOH 5mol.L{sup -1} as precipitating agent. The magnetic nanoparticles were characterized by scanning electron microscopy, infrared spectroscopy, X-ray diffraction, magnetization curves, and thermal analysis. Most of manganese ferrite particles showed superparamagnetic behavior. After the characterization it was found that the samples synthesized manganese ferrite with more than 40 minutes heating time, crystal structure showed the characteristic pattern of the inverted manganese ferrite spinel type. The stabilization of the samples in oleic acid nanoparticles produced with a hydrophobic outer layer and facilitated by coating chitosan biopolymer, since this has a positive charge. Among the doped samples there was no significant change in the magnetic behavior. Several techniques for characterizing these materials have been used such as X-ray diffraction spectrum in the infrared region, magnetization curves and thermal analysis. The resins were tested as magnetic material for the separation of biological materials. In this paper, are used as biological targets separation of bovine serum albumin. (author)

Temperature and concentration quenching of Tb3+ emissions in Y4Al2O9 crystals

International Nuclear Information System (INIS)

Boruc, Z.; Fetlinski, B.; Kaczkan, M.; Turczynski, S.; Pawlak, D.; Malinowski, M.

2012-01-01

Highlights: ► Spectroscopic properties of Tb 3+ :Y 4 Al 2 O 9 crystals are studied. ► Concentration and temperature dependencies of fluorescence are investigated. ► The cross-relaxation transfer rates are experimentally determined. ► Strong influence of cross relaxation process on 5 D 3 emission quenching is observed. ► Decays are modelled using Inokuti–Hirayama approach. - Abstract: Spectroscopic properties of trivalent terbium (Tb 3+ ) activated Y 4 Al 2 O 9 (abbreviated YAM) crystals were studied. Concentration and temperature dependent emission spectra and fluorescence dynamics profiles have been investigated in YAM:Tb 3+ in order to understand better processes responsible for quenching of the terbium 5 D 3 and 5 D 4 emissions. Decays were modelled using Inokuti–Hirayama approach to obtain information on the energy transfer mechanism. The cross-relaxation transfer rates were experimentally determined as a function of temperature and Tb 3+ concentration. The investigation revealed strong influence of cross-relaxation process on 5 D 3 emission quenching. The two different processes responsible for the increase of fluorescence quenching with growing temperature were observed, both related to thermal activation energy. For temperatures above 700 K, the temperature dependence of the emission intensity ratio ( 5 D 3 / 5 D 4 ) becomes linear and the decay times are rapidly decreasing monotonously with increasing temperature, what is confirming the potential of Y 4 Al 2 O 9 :Tb 3+ material in high temperature luminescence thermometry.

Automated technological equipment-robot complexes

International Nuclear Information System (INIS)

Zhitomirskii, S.V.; Samorodskikh, B.L.

1984-01-01

This paper surveys the types of automated technological equipment robot complexes. The principal elements of such complexes are described. Complexes are divided into two principal groups: those using simultaneously acting robots, and those using successively acting robots. The great variety of types of robots using successive action is then described

Managing complex child law

DEFF Research Database (Denmark)

Svendsen, Idamarie Leth

2017-01-01

The article reports the findings of a qualitative study of Danish legal regulation of the public initial assessment of children and young persons and municipal practitioners’ decision-making under this regulation. The regulation mirrors new and complex relations between families and society...... in the form of 7 individual vignette interviews with municipal mid-level managers and professional consultants in five Danish municipalities. The study finds that the regulation is more complex than it looks, and that the complexity is handled through simplifying decision-making patterns that can be seen...

Cyclomatic Complexity: theme and variations

Directory of Open Access Journals (Sweden)

Brian Henderson-Sellers

1993-11-01

Full Text Available Focussing on the "McCabe family" of measures for the decision/logic structure of a program, leads to an evaluation of extensions to modularization, nesting and, potentially, to object-oriented program structures. A comparison of rated, operating and essential complexities of programs suggests two new metrics: "inessential complexity" as a measure of unstructuredness and "product complexity" as a potential objective measure of structural complexity. Finally, nesting and abstraction levels are considered, especially as to how metrics from the "McCabe family" might be applied in an object-oriented systems development environment.

The structure of complex Lie groups

CERN Document Server

Lee, Dong Hoon

2001-01-01

Complex Lie groups have often been used as auxiliaries in the study of real Lie groups in areas such as differential geometry and representation theory. To date, however, no book has fully explored and developed their structural aspects.The Structure of Complex Lie Groups addresses this need. Self-contained, it begins with general concepts introduced via an almost complex structure on a real Lie group. It then moves to the theory of representative functions of Lie groups- used as a primary tool in subsequent chapters-and discusses the extension problem of representations that is essential for studying the structure of complex Lie groups. This is followed by a discourse on complex analytic groups that carry the structure of affine algebraic groups compatible with their analytic group structure. The author then uses the results of his earlier discussions to determine the observability of subgroups of complex Lie groups.The differences between complex algebraic groups and complex Lie groups are sometimes subtle ...

Modeling Complex Systems

CERN Document Server

Boccara, Nino

2010-01-01

Modeling Complex Systems, 2nd Edition, explores the process of modeling complex systems, providing examples from such diverse fields as ecology, epidemiology, sociology, seismology, and economics. It illustrates how models of complex systems are built and provides indispensable mathematical tools for studying their dynamics. This vital introductory text is useful for advanced undergraduate students in various scientific disciplines, and serves as an important reference book for graduate students and young researchers. This enhanced second edition includes: . -recent research results and bibliographic references -extra footnotes which provide biographical information on cited scientists who have made significant contributions to the field -new and improved worked-out examples to aid a student’s comprehension of the content -exercises to challenge the reader and complement the material Nino Boccara is also the author of Essentials of Mathematica: With Applications to Mathematics and Physics (Springer, 2007).

Tensor Product of Polygonal Cell Complexes

OpenAIRE

Chien, Yu-Yen

2017-01-01

We introduce the tensor product of polygonal cell complexes, which interacts nicely with the tensor product of link graphs of complexes. We also develop the unique factorization property of polygonal cell complexes with respect to the tensor product, and study the symmetries of tensor products of polygonal cell complexes.

Organization structures for dealing with complexity

NARCIS (Netherlands)

Meijer, B.R.

2006-01-01

"Complexity is in the eye of the beholder" is a well known quote in the research field of complexity. In the world of managers the word complex is often a synonym for difficult, complicated, involving many factors and highly uncertain. A complex business decision requires careful preparation and

Epidemic modeling in complex realities.

Science.gov (United States)

Colizza, Vittoria; Barthélemy, Marc; Barrat, Alain; Vespignani, Alessandro

2007-04-01

In our global world, the increasing complexity of social relations and transport infrastructures are key factors in the spread of epidemics. In recent years, the increasing availability of computer power has enabled both to obtain reliable data allowing one to quantify the complexity of the networks on which epidemics may propagate and to envision computational tools able to tackle the analysis of such propagation phenomena. These advances have put in evidence the limits of homogeneous assumptions and simple spatial diffusion approaches, and stimulated the inclusion of complex features and heterogeneities relevant in the description of epidemic diffusion. In this paper, we review recent progresses that integrate complex systems and networks analysis with epidemic modelling and focus on the impact of the various complex features of real systems on the dynamics of epidemic spreading.

Provability, complexity, grammars

CERN Document Server

Beklemishev, Lev; Vereshchagin, Nikolai

1999-01-01

The book contains English translations of three outstanding dissertations in mathematical logic and complexity theory. L. Beklemishev proves that all provability logics must belong to one of the four previously known classes. The dissertation of M. Pentus proves the Chomsky conjecture about the equivalence of two approaches to formal languages: the Chomsky hierarchy and the Lambek calculus. The dissertation of N. Vereshchagin describes a general framework for criteria of reversability in complexity theory.

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.

Complexity factors and prediction of performance

International Nuclear Information System (INIS)

Braarud, Per Oeyvind

1998-03-01

Understanding of what makes a control room situation difficult to handle is important when studying operator performance, both with respect to prediction as well as improvement of the human performance. A factor analytic approach identified eight factors from operators' answers to an 39 item questionnaire about complexity of the operator's task in the control room. A Complexity Profiling Questionnaire was developed, based on the factor analytic results from the operators' conception of complexity. The validity of the identified complexity factors was studied by prediction of crew performance and prediction of plant performance from ratings of the complexity of scenarios. The scenarios were rated by both process experts and the operators participating in the scenarios, using the Complexity Profiling Questionnaire. The process experts' complexity ratings predicted both crew performance and plant performance, while the operators' rating predicted plant performance only. The results reported are from initial studies of complexity, and imply a promising potential for further studies of the concept. The approach used in the study as well as the reported results are discussed. A chapter about the structure of the conception of complexity, and a chapter about further research conclude the report. (author)

Neurosurgical implications of Carney complex.

Science.gov (United States)

Watson, J C; Stratakis, C A; Bryant-Greenwood, P K; Koch, C A; Kirschner, L S; Nguyen, T; Carney, J A; Oldfield, E H

2000-03-01

The authors present their neurosurgical experience with Carney complex. Carney complex, characterized by spotty skin pigmentation, cardiac myxomas, primary pigmented nodular adrenocortical disease, pituitary tumors, and nerve sheath tumors (NSTs), is a recently described, rare, autosomal-dominant familial syndrome that is relatively unknown to neurosurgeons. Neurosurgery is required to treat pituitary adenomas and a rare NST, the psammomatous melanotic schwannoma (PMS), in patients with Carney complex. Cushing's syndrome, a common component of the complex, is caused by primary pigmented nodular adrenocortical disease and is not secondary to an adrenocorticotropic hormone-secreting pituitary adenoma. The authors reviewed 14 cases of Carney complex, five from the literature and nine from their own experience. Of the 14 pituitary adenomas recognized in association with Carney complex, 12 developed growth hormone (GH) hypersecretion (producing gigantism in two patients and acromegaly in 10), and results of immunohistochemical studies in one of the other two were positive for GH. The association of PMSs with Carney complex was established in 1990. Of the reported tumors, 28% were associated with spinal nerve sheaths. The spinal tumors occurred in adults (mean age 32 years, range 18-49 years) who presented with pain and radiculopathy. These NSTs may be malignant (10%) and, as with the cardiac myxomas, are associated with significant rates of morbidity and mortality. Because of the surgical comorbidity associated with cardiac myxoma and/or Cushing's syndrome, recognition of Carney complex has important implications for perisurgical patient management and family screening. Study of the genetics of Carney complex and of the biological abnormalities associated with the tumors may provide insight into the general pathobiological abnormalities associated with the tumors may provide insight into the general pathobiological features of pituitary adenomas and NSTs.

Is dense codeswitching complex?

NARCIS (Netherlands)

Dorleijn, M.

In this paper the question is raised to what extent dense code switching can be considered complex. Psycholinguistic experiments indicate that code switching involves cognitive costs, both in production and comprehension, a conclusion that could indicate that code switching is indeed complex. In

Ternary complex formation at mineral/solution interfaces

International Nuclear Information System (INIS)

Leckie, J.O.

1995-01-01

Adsorption of trace concentrations of radionuclides and heavy metals from aqueous solution is dependent on pH, absorbent and adsorbate concentration, and speciation of the metal in solution. In particular, complexation of metal ions by organic and inorganic ligands can dramatically alter adsorption behavior compared to ligand-free systems. The presence of complexing ligands can cause the formation of ''metal like'' or ''ligand like'' ternary surface complexes depending on whether adsorption of the ternary complex increases or decreases with increasing pH, respectively. Examples of ternary surface complexes behaving ''metal like'' include uranyl-EDTA surface complexes on goethite, neptunyl-EDTA surface complexes on hematite and neptunyl-humic surface complexes on gibbsite. Examples of ''ligand like'' ternary surface complexes include uranyl-carbonato and neptunyl-carbonato surface complexes on iron oxides. The effects of complex solutions and multimineralic systems are discussed. (authors). 39 refs., 16 figs., 8 tabs

Information geometric methods for complexity

Science.gov (United States)

Felice, Domenico; Cafaro, Carlo; Mancini, Stefano

2018-03-01

Research on the use of information geometry (IG) in modern physics has witnessed significant advances recently. In this review article, we report on the utilization of IG methods to define measures of complexity in both classical and, whenever available, quantum physical settings. A paradigmatic example of a dramatic change in complexity is given by phase transitions (PTs). Hence, we review both global and local aspects of PTs described in terms of the scalar curvature of the parameter manifold and the components of the metric tensor, respectively. We also report on the behavior of geodesic paths on the parameter manifold used to gain insight into the dynamics of PTs. Going further, we survey measures of complexity arising in the geometric framework. In particular, we quantify complexity of networks in terms of the Riemannian volume of the parameter space of a statistical manifold associated with a given network. We are also concerned with complexity measures that account for the interactions of a given number of parts of a system that cannot be described in terms of a smaller number of parts of the system. Finally, we investigate complexity measures of entropic motion on curved statistical manifolds that arise from a probabilistic description of physical systems in the presence of limited information. The Kullback-Leibler divergence, the distance to an exponential family and volumes of curved parameter manifolds, are examples of essential IG notions exploited in our discussion of complexity. We conclude by discussing strengths, limits, and possible future applications of IG methods to the physics of complexity.

European Conference on Complex Systems 2012

CERN Document Server

Kirkilionis, Markus; Nicolis, Gregoire

2013-01-01

The European Conference on Complex Systems, held under the patronage of the Complex Systems Society, is an annual event that has become the leading European conference devoted to complexity science. ECCS'12, its ninth edition, took place in Brussels, during the first week of September 2012. It gathered about 650 scholars representing a wide range of topics relating to complex systems research, with emphasis on interdisciplinary approaches. More specifically, the following tracks were covered:  1. Foundations of Complex Systems 2. Complexity, Information and Computation 3. Prediction, Policy and Planning, Environment 4. Biological Complexity 5. Interacting Populations, Collective Behavior 6. Social Systems, Economics and Finance This book contains a selection of the contributions presented at the conference and its satellite meetings. Its contents reflect the extent, diversity and richness of research areas in the field, both fundamental and applied.  

Influence of Hydrophobicity on Polyelectrolyte Complexation

Energy Technology Data Exchange (ETDEWEB)

Sadman, Kazi [Department; amp, Engineering, Northwestern University, Evanston, Illinois 60208, United States; Wang, Qifeng [Department; amp, Engineering, Northwestern University, Evanston, Illinois 60208, United States; Chen, Yaoyao [Department; amp, Engineering, Northwestern University, Evanston, Illinois 60208, United States; Keshavarz, Bavand [Department; Jiang, Zhang [X-ray; Shull, Kenneth R. [Department; amp, Engineering, Northwestern University, Evanston, Illinois 60208, United States

2017-11-16

Polyelectrolyte complexes are a fascinating class of soft materials that can span the full spectrum of mechanical properties from low viscosity fluids to glassy solids. This spectrum can be accessed by modulating the extent of electrostatic association in these complexes. However, to realize the full potential of polyelectrolyte complexes as functional materials their molecular level details need to be clearly correlated with their mechanical response. The present work demonstrates that by making simple amendments to the chain architecture it is possible to affect the salt responsiveness of polyelectrolyte complexes in a systematic manner. This is achieved by quaternizing poly(4-vinylpyridine) (QVP) with methyl, ethyl and propyl substituents– thereby increasing the hydrophobicity with increasing side chain length– and complexing them with a common anionic polyelectrolyte, poly(styrene sulfonate). The mechanical 1 ACS Paragon Plus Environment behavior of these complexes is compared to the more hydrophilic system of poly(styrene sulfonate) and poly(diallyldimethylammonium) by quantifying the swelling behavior in response to salt stimuli. More hydrophobic complexes are found to be more resistant to doping by salt, yet the mechanical properties of the complex remain contingent on the overall swelling ratio of the complex itself, following near universal swelling-modulus master curves that are quantified in this work. The rheological behavior of QVP complex coacervates are found to be approximately the same, only requiring higher salt concentrations to overcome strong hydrophobic interactions, demonstrating that hydrophobicity can be used as an important parameter for tuning the stability of polyelectrolyte complexes in general, while still preserving the ability to be processed “saloplastically”.

Complexity leadership: a healthcare imperative.

Science.gov (United States)

Weberg, Dan

2012-01-01

The healthcare system is plagued with increasing cost and poor quality outcomes. A major contributing factor for these issues is that outdated leadership practices, such as leader-centricity, linear thinking, and poor readiness for innovation, are being used in healthcare organizations. Complexity leadership theory provides a new framework with which healthcare leaders may practice leadership. Complexity leadership theory conceptualizes leadership as a continual process that stems from collaboration, complex systems thinking, and innovation mindsets. Compared to transactional and transformational leadership concepts, complexity leadership practices hold promise to improve cost and quality in health care. © 2012 Wiley Periodicals, Inc.

Size matters: nanoparticles in cancer therapy

International Nuclear Information System (INIS)

Khullar, Bhavya; Iqbal, Sarah

2016-01-01

Scientists at the CSIR-National Chemical Laboratory, Pune, in collaboration with universities in Lucknow and Aligarh, synthesized terbium oxide (Tb_2O_3) nanoparticles by putting a naturally occurring fungus into action. Commercially available Tb_4O_7 is reduced to Tb_2O_3 by incubating it with a suspension of Fusarium oxysporum in controlled conditions of pH and temperature. The aqueous crystals of Tb_2O_3, isolated from the fungal suspension, were stable and did not form aggregates or clumps. Hence, they could be isolated as crystals with long-term stability

Neutron activation analysis of the rare earth elements in Nasu hot springs

International Nuclear Information System (INIS)

Ikeda, Nagao; Takahashi, Naruto.

1978-01-01

Eleven rare earth elements (lanthanum, cerium, neodymium, samarium, europium, gadolinium, terbium, holmium, thulium, ytterbium and lutetium) in hot spring waters and sinter deposits in the Nasu area were determined by the neutron activation method. The rare earth elements in hot spring water were preconcentrated in ferric hydroxide precipitate and neutron-irradiated. The rare earth elements were chemically separated into lighter and heavier groups and the activity of each group was measured with a Ge(Li) detector. Distribution of the rare earth elements between the hot spring water and the sinter deposit was also discussed. (auth.)

Time-resolved fluoroimmunoassay of phytoviruses by monoclonal antibodies. Vremenno-razreshennyj fluoroimmunoanaliz fitovirusos pri pomoshchi monoklonal'nykh antitel

Energy Technology Data Exchange (ETDEWEB)

Saarma, M Yu; Yarvekyul' g, L V; Andreeva, E G; Siniyarv, R K

1989-01-01

Monoclonal antibodies (MAbs) to potato viruses were labelled with lanthanides and used for time-resolved fluoroimmunoassay (TRFIA) of these viruses. TRFIA of potato leafroll virus (PLRV) had the sensitivity less than 1 ng/ml and was therefore approx 10 times more sensitive than ELISA. Possibility of simultaneous quantitative detection of several viruses by different MAbs labelled with europium, samarium and terbium provides TRFIA of fundamental advantage. Data on simultaneous sensitive detection of two viruses - PLRV and PVX (0,5 ng/ml of both) and three viruses - PLRV, PVX and PVM are given.

COMPLEX TRAINING: A BRIEF REVIEW

Directory of Open Access Journals (Sweden)

William P. Ebben

2002-06-01

Full Text Available The effectiveness of plyometric training is well supported by research. Complex training has gained popularity as a training strategy combining weight training and plyometric training. Anecdotal reports recommend training in this fashion in order to improve muscular power and athletic performance. Recently, several studies have examined complex training. Despite the fact that questions remain about the potential effectiveness and implementation of this type of training, results of recent studies are useful in guiding practitioners in the development and implementation of complex training programs. In some cases, research suggests that complex training has an acute ergogenic effect on upper body power and the results of acute and chronic complex training include improved jumping performance. Improved performance may require three to four minutes rest between the weight training and plyometrics sets and the use of heavy weight training loads

European Conference on Complex Systems

CERN Document Server

Pellegrini, Francesco; Caldarelli, Guido; Merelli, Emanuela

2016-01-01

This work contains a stringent selection of extended contributions presented at the meeting of 2014 and its satellite meetings, reflecting scope, diversity and richness of research areas in the field, both fundamental and applied. The ECCS meeting, held under the patronage of the Complex Systems Society, is an annual event that has become the leading European conference devoted to complexity science. It offers cutting edge research and unique opportunities to study novel scientific approaches in a multitude of application areas. ECCS'14, its eleventh occurrence, took place in Lucca, Italy. It gathered some 650 scholars representing a wide range of topics relating to complex systems research, with emphasis on interdisciplinary approaches. The editors are among the best specialists in the area. The book is of great interest to scientists, researchers and graduate students in complexity, complex systems and networks.

The Seis Lagos Carbonatite Complex

International Nuclear Information System (INIS)

Issler, R.S.; Silva, G.G. da.

1980-01-01

The Seis Lagos Carbonatite Complex located about 840 Km from Manaus, on the northwestern part of the Estado do Amazonas, Brazil is described. Geological reconnaissance mapping by Radam Project/DNPM, of the southwestern portion of the Guianes Craton, determined three circular features arranged in a north-south trend and outcroping as thick lateritic radioactive hills surrounded by gneisses and mignatites of the peneplained Guianense Complex. Results of core drilling samples analysis of the Seis Lagos Carbonatite Complex are compared with some igneous rocks and limestones of the world on the basis of abundance of their minor and trace elements. Log-log variation diagram of strontium and barium in carbonatite and limestone, exemplifield by South Africa and Angola carbonatites, are compared with the Seis Lagos Carbonatite Complex. The Seis Lagos Carbonatite Complex belongs to the siderite-soevite type. (E.G.) [pt

Complex/Symplectic Mirrors

Energy Technology Data Exchange (ETDEWEB)

Chuang, Wu-yen; Kachru, Shamit; /Stanford U., ITP /SLAC; Tomasiello, Alessandro; /Stanford U., ITP

2005-10-28

We construct a class of symplectic non-Kaehler and complex non-Kaehler string theory vacua, extending and providing evidence for an earlier suggestion by Polchinski and Strominger. The class admits a mirror pairing by construction. Comparing hints from a variety of sources, including ten-dimensional supergravity and KK reduction on SU(3)-structure manifolds, suggests a picture in which string theory extends Reid's fantasy to connect classes of both complex non-Kaehler and symplectic non-Kaehler manifolds.

Disentangling Complexity from Randomness and Chaos

Directory of Open Access Journals (Sweden)

Lena C. Zuchowski

2012-02-01

Full Text Available This study aims to disentangle complexity from randomness and chaos, and to present a definition of complexity that emphasizes its epistemically distinct qualities. I will review existing attempts at defining complexity and argue that these suffer from two major faults: a tendency to neglect the underlying dynamics and to focus exclusively on the phenomenology of complex systems; and linguistic imprecisions in describing these phenomenologies. I will argue that the tendency to discuss phenomenology removed from the underlying dynamics is the main root of the difficulties in distinguishing complex from chaotic or random systems. In my own definition, I will explicitly try to avoid these pitfalls. The theoretical contemplations in this paper will be tested on a sample of five models: the random Kac ring, the chaotic CA30, the regular CA90, the complex CA110 and the complex Bak-Sneppen model. Although these modelling studies are restricted in scope and can only be seen as preliminary, they still constitute on of the first attempts to investigate complex systems comparatively.

Extending Life Concepts to Complex Systems

Directory of Open Access Journals (Sweden)

Jean Le Fur

2013-01-01

Full Text Available There is still no consensus definition of complex systems. This article explores, as a heuristic approach, the possibility of using notions associated with life as transversal concepts for defining complex systems. This approach is developed within a general classification of systems, with complex systems considered as a general ‘living things’ category and living organisms as a specialised class within this category. Concepts associated with life are first explored in the context of complex systems: birth, death and lifetime, adaptation, ontogeny and growth, reproduction. Thereafter, a refutation approach is used to test the proposed classification against a set of diverse systems, including a reference case, edge cases and immaterial complex systems. The summary of this analysis is then used to generate a definition of complex systems, based on the proposal, and within the background of cybernetics, complex adaptive systems and biology. Using notions such as ‘birth’ or ‘lifespan’ as transversal concepts may be of heuristic value for the generic characterization of complex systems, opening up new lines of research for improving their definition.

Complexation of buffer constituents with neutral complexation agents: part I. Impact on common buffer properties.

Science.gov (United States)

Riesová, Martina; Svobodová, Jana; Tošner, Zdeněk; Beneš, Martin; Tesařová, Eva; Gaš, Bohuslav

2013-09-17

The complexation of buffer constituents with the complexation agent present in the solution can very significantly influence the buffer properties, such as pH, ionic strength, or conductivity. These parameters are often crucial for selection of the separation conditions in capillary electrophoresis or high-pressure liquid chromatography (HPLC) and can significantly affect results of separation, particularly for capillary electrophoresis as shown in Part II of this paper series (Beneš, M.; Riesová, M.; Svobodová, J.; Tesařová, E.; Dubský, P.; Gaš, B. Anal. Chem. 2013, DOI: 10.1021/ac401381d). In this paper, the impact of complexation of buffer constituents with a neutral complexation agent is demonstrated theoretically as well as experimentally for the model buffer system composed of benzoic acid/LiOH or common buffers (e.g., CHES/LiOH, TAPS/LiOH, Tricine/LiOH, MOPS/LiOH, MES/LiOH, and acetic acid/LiOH). Cyclodextrins as common chiral selectors were used as model complexation agents. We were not only able to demonstrate substantial changes of pH but also to predict the general complexation characteristics of selected compounds. Because of the zwitterion character of the common buffer constituents, their charged forms complex stronger with cyclodextrins than the neutral ones do. This was fully proven by NMR measurements. Additionally complexation constants of both forms of selected compounds were determined by NMR and affinity capillary electrophoresis with a very good agreement of obtained values. These data were advantageously used for the theoretical descriptions of variations in pH, depending on the composition and concentration of the buffer. Theoretical predictions were shown to be a useful tool for deriving some general rules and laws for complexing systems.

Alanine water complexes.

Science.gov (United States)

Vaquero, Vanesa; Sanz, M Eugenia; Peña, Isabel; Mata, Santiago; Cabezas, Carlos; López, Juan C; Alonso, José L

2014-04-10

Two complexes of alanine with water, alanine-(H2O)n (n = 1,2), have been generated by laser ablation of the amino acid in a supersonic jet containing water vapor and characterized using Fourier transform microwave spectroscopy. In the observed complexes, water molecules bind to the carboxylic group of alanine acting as both proton donors and acceptors. In alanine-H2O, the water molecule establishes two intermolecular hydrogen bonds forming a six-membered cycle, while in alanine-(H2O)2 the two water molecules establish three hydrogen bonds forming an eight-membered ring. In both complexes, the amino acid moiety is in its neutral form and shows the conformation observed to be the most stable for the bare molecule. The microsolvation study of alanine-(H2O)n (n = 1,2) can be taken as a first step toward understanding bulk properties at a microscopic level.

Solution chemistry of lanthanide complexes

International Nuclear Information System (INIS)

Brittain, H.G.

1979-01-01

Intermolecular energy transfer from Tb 3+ to Eu 3+ , luminescence intensity measurements, potentiometric titrations, differential absorption spectroscopy, and spectroscopic titrations were all used to study the binding of lanthanide ions by serine and threonine. At low pH (3.0 to 6.0) the complexes are mononuclear and ligand is only weakly bound. In the pH interval of 6.0 to 8.5 stronger interaction takes place between the ligand and the metal (with possible coordination of the undissociated hydroxyl group), and self-association of complexes becomes important. Above pH 8.5, base hydrolysis of the complexes leads to highly associated species in solution and shortly above this pH an insoluble precipitate is formed. It was found that energy could be transferred from Tb 3+ to Eu 3+ more efficiently among complexes prepared from racemic ligands than in complexes made from resolved ligand, but this stereoselectivity was only observed at pH values greater than 6.5 and in solutions having a 1:10 ratio of metal-to-ligand. No stereoselectivity was found in solutions having 1:5 ratios, and this observation was explained by the existence of 1:2 metal-ligand complexes existing in solutions having the higher ratio of metal-to-ligand (only 1:1 complexes are then found at lower ratios of metal-to-ligand). (author)

Real and complex analysis

CERN Document Server

Apelian, Christopher; Taft, Earl; Nashed, Zuhair

2009-01-01

The Spaces R, Rk, and CThe Real Numbers RThe Real Spaces RkThe Complex Numbers CPoint-Set Topology Bounded SetsClassification of Points Open and Closed SetsNested Intervals and the Bolzano-Weierstrass Theorem Compactness and Connectedness Limits and Convergence Definitions and First Properties Convergence Results for SequencesTopological Results for Sequences Properties of Infinite SeriesManipulations of Series in RFunctions: Definitions and Limits DefinitionsFunctions as MappingsSome Elementary Complex FunctionsLimits of FunctionsFunctions: Continuity and Convergence Continuity Uniform Continuity Sequences and Series of FunctionsThe DerivativeThe Derivative for f: D1 → RThe Derivative for f: Dk → RThe Derivative for f: Dk → RpThe Derivative for f: D → CThe Inverse and Implicit Function TheoremsReal IntegrationThe Integral of f: [a, b] → RProperties of the Riemann Integral Further Development of Integration TheoryVector-Valued and Line IntegralsComplex IntegrationIntroduction to Complex Integrals Fu...

Unifying Complexity and Information

Science.gov (United States)

Ke, Da-Guan

2013-04-01

Complex systems, arising in many contexts in the computer, life, social, and physical sciences, have not shared a generally-accepted complexity measure playing a fundamental role as the Shannon entropy H in statistical mechanics. Superficially-conflicting criteria of complexity measurement, i.e. complexity-randomness (C-R) relations, have given rise to a special measure intrinsically adaptable to more than one criterion. However, deep causes of the conflict and the adaptability are not much clear. Here I trace the root of each representative or adaptable measure to its particular universal data-generating or -regenerating model (UDGM or UDRM). A representative measure for deterministic dynamical systems is found as a counterpart of the H for random process, clearly redefining the boundary of different criteria. And a specific UDRM achieving the intrinsic adaptability enables a general information measure that ultimately solves all major disputes. This work encourages a single framework coving deterministic systems, statistical mechanics and real-world living organisms.

Workspace Program for Complex-Number Arithmetic

Science.gov (United States)

Patrick, M. C.; Howell, Leonard W., Jr.

1986-01-01

COMPLEX is workspace program designed to empower APL with complexnumber capabilities. Complex-variable methods provide analytical tools invaluable for applications in mathematics, science, and engineering. COMPLEX written in APL.

Is a "Complex" Task Really Complex? Validating the Assumption of Cognitive Task Complexity

Science.gov (United States)

Sasayama, Shoko

2016-01-01

In research on task-based learning and teaching, it has traditionally been assumed that differing degrees of cognitive task complexity can be inferred through task design and/or observations of differing qualities in linguistic production elicited by second language (L2) communication tasks. Without validating this assumption, however, it is…

Linearization Method and Linear Complexity

Science.gov (United States)

Tanaka, Hidema

We focus on the relationship between the linearization method and linear complexity and show that the linearization method is another effective technique for calculating linear complexity. We analyze its effectiveness by comparing with the logic circuit method. We compare the relevant conditions and necessary computational cost with those of the Berlekamp-Massey algorithm and the Games-Chan algorithm. The significant property of a linearization method is that it needs no output sequence from a pseudo-random number generator (PRNG) because it calculates linear complexity using the algebraic expression of its algorithm. When a PRNG has n [bit] stages (registers or internal states), the necessary computational cost is smaller than O(2n). On the other hand, the Berlekamp-Massey algorithm needs O(N2) where N(≅2n) denotes period. Since existing methods calculate using the output sequence, an initial value of PRNG influences a resultant value of linear complexity. Therefore, a linear complexity is generally given as an estimate value. On the other hand, a linearization method calculates from an algorithm of PRNG, it can determine the lower bound of linear complexity.

Complex conductivity of soils

NARCIS (Netherlands)

Revil, A.; Coperey, A.; Shao, Z.; Florsch, N.; Fabricus, I.L.; Deng, Y.; Delsman, J.R.; Pauw, P.S.; Karaoulis, M.; Louw, P.G.B. de; Baaren, E.S. van; Dabekaussen, W.; Menkovic, A.; Gunnink, J.L.

2017-01-01

The complex conductivity of soils remains poorly known despite the growing importance of this method in hydrogeophysics. In order to fill this gap of knowledge, we investigate the complex conductivity of 71 soils samples (including four peat samples) and one clean sand in the frequency range 0.1 Hz

Complexity Metrics for Workflow Nets

DEFF Research Database (Denmark)

Lassen, Kristian Bisgaard; van der Aalst, Wil M.P.

2009-01-01

analysts have difficulties grasping the dynamics implied by a process model. Recent empirical studies show that people make numerous errors when modeling complex business processes, e.g., about 20 percent of the EPCs in the SAP reference model have design flaws resulting in potential deadlocks, livelocks......, etc. It seems obvious that the complexity of the model contributes to design errors and a lack of understanding. It is not easy to measure complexity, however. This paper presents three complexity metrics that have been implemented in the process analysis tool ProM. The metrics are defined...... for a subclass of Petri nets named Workflow nets, but the results can easily be applied to other languages. To demonstrate the applicability of these metrics, we have applied our approach and tool to 262 relatively complex Protos models made in the context of various student projects. This allows us to validate...

Complex quantum groups

International Nuclear Information System (INIS)

Drabant, B.; Schlieker, M.

1993-01-01

The complex quantum groups are constructed. They are q-deformations of the real Lie groups which are obtained as the complex groups corresponding to the Lie algebras of type A n-1 , B n , C n . Following the ideas of Faddeev, Reshetikhin and Takhtajan Hopf algebras of regular functionals U R for these complexified quantum groups are constructed. One has thus in particular found a construction scheme for the q-Lorentz algebra to be identified as U(sl q (2,C). (orig.)

Complexity Intelligence and Cultural Coaching:

Directory of Open Access Journals (Sweden)

Jan Inglis

2005-06-01

Full Text Available In this article, we present the term complexity intelligence as a useful moniker to describe the reasoning ability, emotional capacity and social cognition necessary to meet the challenges of our prevailing life conditions. We suggest that, as a society and as individuals, we develop complexity intelligence as we navigate the gap between our current capacities and the capacities needed to respond to the next stage of complex challenges in our lives. We further suggest that it is possible to stimulate and support the emergence of complexity intelligence in a society, but we need a new form of social change agent - a cultural coach, to midwife its emergence.

Complex manifolds in relativity

International Nuclear Information System (INIS)

Flaherty, E.J. Jr.

1975-01-01

Complex manifold theory is applied to the study of certain problems in general relativity. The first half of the work is devoted to the mathematical theory of complex manifold. Then a brief review of general relativity is given. It is shown that any spacetime admits locally an almost Hermitian structure, suitably modified to be compatible with the indefinite metric of spacetime. This structure is integrable if and only if the spacetime admits two geodesic and shearfree null congruences, thus in particular if the spacetime is type D vacuum or electrified. The structure is ''half-integrable'' in a suitable sense if and only if the spacetime admits one geodesic and shearfree null congruence, thus in particular for all algebraically special vacuum spacetimes. Conditions for the modified Hermitian spacetime to be Kahlerian are presented. The most general metric for such a modified Kahlerian spacetime is found. It is shown that the type D vacuum and electrified spacetimes are conformally related to modified Kahlerian spacetimes by a generally complex conformal factor. These latter are shown to possess a very rich structure, including the existence of Killing tensors and Killing vectors. A new ''explanation'' of Newman's complex coordinate transformations is given. It is felt to be superior to previous ''explanations'' on several counts. For example, a physical interpretation in terms of a symmetry group is given. The existence of new complex coordinate transformations is established: Nt is shown that any type D vacuum spacetime is obtainable from either Schwarzschild spacetime or ''C'' spacetime by a complex coordinate transformation. Finally, some related topics are discussed and areas for future work are outlined. (Diss. Abstr. Int., B)

Leadership and transitions: maintaining the science in complexity and complex systems.

Science.gov (United States)

Sturmberg, Joachim P; Martin, Carmel M

2012-02-01

It is the 'moral compass', however subtle, that underpins leadership. Leadership, meaning showing the way, demands as much conviction as gentile diplomacy in the discourse with supporters and detractors. In particular, leadership defends the goal by safeguarding its principles from its detractors. The authors writing in the Forum on Complexity in Medicine and Healthcare since its inception are leaders in an intellectual transition to complex systems thinking in medicine and health. © 2012 Blackwell Publishing Ltd.

Assessing Complexity in Learning Outcomes--A Comparison between the SOLO Taxonomy and the Model of Hierarchical Complexity

Science.gov (United States)

Stålne, Kristian; Kjellström, Sofia; Utriainen, Jukka

2016-01-01

An important aspect of higher education is to educate students who can manage complex relationships and solve complex problems. Teachers need to be able to evaluate course content with regard to complexity, as well as evaluate students' ability to assimilate complex content and express it in the form of a learning outcome. One model for evaluating…

Managing and engineering in complex situations

CERN Document Server

Sousa-Poza, Andres

2013-01-01

With so many terms available to define the same thing, it would seem nearly irresponsible to introduce yet another term (complex situation) to describe a phenomenological state of such as a system. However, a complex situation infers both a broader meaning and imposes a different perspective. Complex in this context is dependent on understanding and reality rather than observer and knowledge.   Situation imposes a gestalt that cannot be characterized within a singular perspective that relegates paradox to a superior/subordinate hierarchy. This also infers that complex situation has no monotonic definition or each definition is by default incomplete. Therefore the perennial derivations for systems such as complex systems, system of systems, federation of systems is no longer a sufficient descriptor for complex situation.  Ergo system and its genealogy lack the constitution to define complex situations. The books' intent is to explore this pathology through a series of papers written by authors that work in ...

Complexation of carboxylate on smectite surfaces.

Science.gov (United States)

Liu, Xiandong; Lu, Xiancai; Zhang, Yingchun; Zhang, Chi; Wang, Rucheng

2017-07-19

We report a first principles molecular dynamics (FPMD) study of carboxylate complexation on clay surfaces. By taking acetate as a model carboxylate, we investigate its inner-sphere complexes adsorbed on clay edges (including (010) and (110) surfaces) and in interlayer space. Simulations show that acetate forms stable monodentate complexes on edge surfaces and a bidentate complex with Ca 2+ in the interlayer region. The free energy calculations indicate that the complexation on edge surfaces is slightly more stable than in interlayer space. By integrating pK a s and desorption free energies of Al coordinated water calculated previously (X. Liu, X. Lu, E. J. Meijer, R. Wang and H. Zhou, Geochim. Cosmochim. Acta, 2012, 81, 56-68; X. Liu, J. Cheng, M. Sprik, X. Lu and R. Wang, Geochim. Cosmochim. Acta, 2014, 140, 410-417), the pH dependence of acetate complexation has been revealed. It shows that acetate forms inner-sphere complexes on (110) in a very limited mildly acidic pH range while it can complex on (010) in the whole common pH range. The results presented in this study form a physical basis for understanding the geochemical processes involving clay-organics interactions.

An index of floodplain surface complexity

Science.gov (United States)

Scown, Murray W.; Thoms, Martin C.; DeJager, Nathan R.

2016-01-01

Floodplain surface topography is an important component of floodplain ecosystems. It is the primary physical template upon which ecosystem processes are acted out, and complexity in this template can contribute to the high biodiversity and productivity of floodplain ecosystems. There has been a limited appreciation of floodplain surface complexity because of the traditional focus on temporal variability in floodplains as well as limitations to quantifying spatial complexity. An index of floodplain surface complexity (FSC) is developed in this paper and applied to eight floodplains from different geographic settings. The index is based on two key indicators of complexity, variability in surface geometry (VSG) and the spatial organisation of surface conditions (SPO), and was determined at three sampling scales. FSC, VSG, and SPO varied between the eight floodplains and these differences depended upon sampling scale. Relationships between these measures of spatial complexity and seven geomorphological and hydrological drivers were investigated. There was a significant decline in all complexity measures with increasing floodplain width, which was explained by either a power, logarithmic, or exponential function. There was an initial rapid decline in surface complexity as floodplain width increased from 1.5 to 5 km, followed by little change in floodplains wider than 10 km. VSG also increased significantly with increasing sediment yield. No significant relationships were determined between any of the four hydrological variables and floodplain surface complexity.

Moessbauer study of iron-sugar complexes

International Nuclear Information System (INIS)

Tonkovic, M.; Music, S.; Hadzija, O.; Nagy-Czako, I.; Vertes, A.

1982-01-01

Ferric-fructose complex has been prepared using FeCl 3 and Fe(NO 3 ) 3 solutions. Molecular weight determination and Moessbauer spectroscopic measurements proved that the ferric-fructose complex is polymeric in solid state and also in aqueous solution. The synthesis of a new iron-sorbose complex has been performed. Its Moessbauer spectra indicate a structure similar to that of the iron-fructose complex. (author)

A study on the identification of cognitive complexity factors related to the complexity of procedural steps

Energy Technology Data Exchange (ETDEWEB)

Park, Jin Kyun; Jeong, Kwang Sup; Jung, Won Dea [KAERI, Taejon (Korea, Republic of)

2004-07-01

In complex systems, it is well recognized that the provision of understandable procedures that allow operators to clarify 'what needs to be done' and 'how to do it' is one of the requisites to confirm their safety. In this regard, the step complexity (SC) measure that can quantify the complexity of procedural steps in emergency operating procedures (EOPs) of a nuclear power plant (NPP) was suggested. However, the necessity of additional complexity factors that can consider a cognitive aspect in evaluating the complexity of procedural steps is evinced from the comparisons between SC scores and operators' performance data. To this end, the comparisons between operators' performance data with their behavior in conducting prescribed activities of procedural steps are conducted in this study. As a result, two kinds of complexity factors (the abstraction level of knowledge and the level of engineering decision) that could affect operators' cognitive burden are identified. Although a well-designed experiment is indispensable in confirming the appropriateness of cognitive complexity factors, it is strongly believed that the change of an operator's performance can be more authentically explained if they are taken into consideration.

A study on the identification of cognitive complexity factors related to the complexity of procedural steps

International Nuclear Information System (INIS)

Park, Jin Kyun; Jeong, Kwang Sup; Jung, Won Dea

2004-01-01

In complex systems, it is well recognized that the provision of understandable procedures that allow operators to clarify 'what needs to be done' and 'how to do it' is one of the requisites to confirm their safety. In this regard, the step complexity (SC) measure that can quantify the complexity of procedural steps in emergency operating procedures (EOPs) of a nuclear power plant (NPP) was suggested. However, the necessity of additional complexity factors that can consider a cognitive aspect in evaluating the complexity of procedural steps is evinced from the comparisons between SC scores and operators' performance data. To this end, the comparisons between operators' performance data with their behavior in conducting prescribed activities of procedural steps are conducted in this study. As a result, two kinds of complexity factors (the abstraction level of knowledge and the level of engineering decision) that could affect operators' cognitive burden are identified. Although a well-designed experiment is indispensable in confirming the appropriateness of cognitive complexity factors, it is strongly believed that the change of an operator's performance can be more authentically explained if they are taken into consideration

Three perspectives on complexity: entropy, compression, subsymmetry

Science.gov (United States)

Nagaraj, Nithin; Balasubramanian, Karthi

2017-12-01

There is no single universally accepted definition of `Complexity'. There are several perspectives on complexity and what constitutes complex behaviour or complex systems, as opposed to regular, predictable behaviour and simple systems. In this paper, we explore the following perspectives on complexity: effort-to-describe (Shannon entropy H, Lempel-Ziv complexity LZ), effort-to-compress (ETC complexity) and degree-of-order (Subsymmetry or SubSym). While Shannon entropy and LZ are very popular and widely used, ETC is relatively a new complexity measure. In this paper, we also propose a novel normalized complexity measure SubSym based on the existing idea of counting the number of subsymmetries or palindromes within a sequence. We compare the performance of these complexity measures on the following tasks: (A) characterizing complexity of short binary sequences of lengths 4 to 16, (B) distinguishing periodic and chaotic time series from 1D logistic map and 2D Hénon map, (C) analyzing the complexity of stochastic time series generated from 2-state Markov chains, and (D) distinguishing between tonic and irregular spiking patterns generated from the `Adaptive exponential integrate-and-fire' neuron model. Our study reveals that each perspective has its own advantages and uniqueness while also having an overlap with each other.

Softball Complex

Science.gov (United States)

Ellis, Jim

1977-01-01

The Parks and Recreation Department of Montgomery, Alabama, has developed a five-field softball complex as part of a growing community park with facilities for camping, golf, aquatics, tennis, and picnicking. (MJB)

Complex centers of polynomial differential equations

Directory of Open Access Journals (Sweden)

Mohamad Ali M. Alwash

2007-07-01

Full Text Available We present some results on the existence and nonexistence of centers for polynomial first order ordinary differential equations with complex coefficients. In particular, we show that binomial differential equations without linear terms do not have complex centers. Classes of polynomial differential equations, with more than two terms, are presented that do not have complex centers. We also study the relation between complex centers and the Pugh problem. An algorithm is described to solve the Pugh problem for equations without complex centers. The method of proof involves phase plane analysis of the polar equations and a local study of periodic solutions.

Method of complex scaling

International Nuclear Information System (INIS)

Braendas, E.

1986-01-01

The method of complex scaling is taken to include bound states, resonances, remaining scattering background and interference. Particular points of the general complex coordinate formulation are presented. It is shown that care must be exercised to avoid paradoxical situations resulting from inadequate definitions of operator domains. A new resonance localization theorem is presented

Visual Complexity: A Review

Science.gov (United States)

Donderi, Don C.

2006-01-01

The idea of visual complexity, the history of its measurement, and its implications for behavior are reviewed, starting with structuralism and Gestalt psychology at the beginning of the 20th century and ending with visual complexity theory, perceptual learning theory, and neural circuit theory at the beginning of the 21st. Evidence is drawn from…

Simple, complex and hyper-complex understanding - enhanced sensitivity in observation of information

DEFF Research Database (Denmark)

Bering Keiding, Tina

for construction and analysis of empirical information. A quick overview on empirical research drawing on Luhmann reveals a diverse complex of analytical strategies and empirical methods. Despite differences between strategies and methods they have in common that understanding of uttered information is crucial...... in their production of empirically founded knowledge. However research generally seems to pay more attention to production of uttered information than to selection of understanding. The aim of this contribution is to sketch out a suggestion to how selection of understanding can be systematized in order to produce...... enhanced transparency in selection of understanding as well as enhanced sensitivity and definition in dept. The contribution suggest that we distinguish between three types of understanding; simple, complex and hyper-complex understanding. Simple understanding is the simultaneous selection of understanding...

Complex Polynomial Vector Fields

DEFF Research Database (Denmark)

Dias, Kealey

vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... of parameter spaces into structurally stable domains, and a description of the bifurcations. For this reason, the talk will focus on these questions for complex polynomial vector fields.......The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...

Encyclopedia of Complexity and Systems Science

CERN Document Server

Meyers, Robert A

2009-01-01

Encyclopedia of Complexity and Systems Science provides an authoritative single source for understanding and applying the concepts of complexity theory together with the tools and measures for analyzing complex systems in all fields of science and engineering. The science and tools of complexity and systems science include theories of self-organization, complex systems, synergetics, dynamical systems, turbulence, catastrophes, instabilities, nonlinearity, stochastic processes, chaos, neural networks, cellular automata, adaptive systems, and genetic algorithms. Examples of near-term problems and major unknowns that can be approached through complexity and systems science include: The structure, history and future of the universe; the biological basis of consciousness; the integration of genomics, proteomics and bioinformatics as systems biology; human longevity limits; the limits of computing; sustainability of life on earth; predictability, dynamics and extent of earthquakes, hurricanes, tsunamis, and other n...

Epidemic processes in complex networks

OpenAIRE

Pastor Satorras, Romualdo; Castellano, Claudio; Van Mieghem, Piet; Vespignani, Alessandro

2015-01-01

In recent years the research community has accumulated overwhelming evidence for the emergence of complex and heterogeneous connectivity patterns in a wide range of biological and sociotechnical systems. The complex properties of real-world networks have a profound impact on the behavior of equilibrium and nonequilibrium phenomena occurring in various systems, and the study of epidemic spreading is central to our understanding of the unfolding of dynamical processes in complex networks. The t...

Bell Inequalities for Complex Networks

Science.gov (United States)

2015-10-26

AFRL-AFOSR-VA-TR-2015-0355 YIP Bell Inequalities for Complex Networks Greg Ver Steeg UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES Final Report 10/26...performance report PI: Greg Ver Steeg Young Investigator Award Grant Title: Bell Inequalities for Complex Networks Grant #: FA9550-12-1-0417 Reporting...October 20, 2015 Final Report for “Bell Inequalities for Complex Networks” Greg Ver Steeg Abstract This effort studied new methods to understand the effect

Resilience and Complexity

DEFF Research Database (Denmark)

Dahlberg, Rasmus

2015-01-01

This paper explores two key concepts: resilience and complexity. The first is understood as an emergent property of the latter, and their inter-relatedness is discussed using a three tier approach. First, by exploring the discourse of each concept, next, by analyzing underlying relationships and...... robust. Robustness is a property of simple or complicated systems characterized by predictable behavior, enabling the system to bounce back to its normal state following a perturbation. Resilience, however, is an emergent property of complex adaptive systems. It is suggested that this distinction...

Relating Complexity and Error Rates of Ontology Concepts. More Complex NCIt Concepts Have More Errors.

Science.gov (United States)

Min, Hua; Zheng, Ling; Perl, Yehoshua; Halper, Michael; De Coronado, Sherri; Ochs, Christopher

2017-05-18

Ontologies are knowledge structures that lend support to many health-information systems. A study is carried out to assess the quality of ontological concepts based on a measure of their complexity. The results show a relation between complexity of concepts and error rates of concepts. A measure of lateral complexity defined as the number of exhibited role types is used to distinguish between more complex and simpler concepts. Using a framework called an area taxonomy, a kind of abstraction network that summarizes the structural organization of an ontology, concepts are divided into two groups along these lines. Various concepts from each group are then subjected to a two-phase QA analysis to uncover and verify errors and inconsistencies in their modeling. A hierarchy of the National Cancer Institute thesaurus (NCIt) is used as our test-bed. A hypothesis pertaining to the expected error rates of the complex and simple concepts is tested. Our study was done on the NCIt's Biological Process hierarchy. Various errors, including missing roles, incorrect role targets, and incorrectly assigned roles, were discovered and verified in the two phases of our QA analysis. The overall findings confirmed our hypothesis by showing a statistically significant difference between the amounts of errors exhibited by more laterally complex concepts vis-à-vis simpler concepts. QA is an essential part of any ontology's maintenance regimen. In this paper, we reported on the results of a QA study targeting two groups of ontology concepts distinguished by their level of complexity, defined in terms of the number of exhibited role types. The study was carried out on a major component of an important ontology, the NCIt. The findings suggest that more complex concepts tend to have a higher error rate than simpler concepts. These findings can be utilized to guide ongoing efforts in ontology QA.

I. Redox chemistry of bimetallic fulvalene complexes II. Oligocyclopentadienyl complexes

Energy Technology Data Exchange (ETDEWEB)

Brown, David Stephen [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; Lawrence Berkeley Lab., CA (United States). Chemical Sciences Div.

1993-11-01

The electrochemistry of the heterobimetallic complexes (fulvalene)WFe(CO)₅ (30) and (fulvalene)WRu(CO)₅ (31) has been investigated. Compound 30 is reduced in two one-electron processes, and this behavior was exploited synthetically to prepare a tetranuclear dimer by selective metal reduction. Complex 31 displayed a distinction between the metals upon reoxidation of the dianion, allowing the formation of a dimer by selective metal anion oxidation. The redox behavior of 30 led to an investigation of the use of electrocatalysis to effect metal-specific ligand substitution. It was found that reduction of 30 with a catalytic amount of CpFe(C₆Me₆) (97) in the presence of excess P(OMe)₃ or PMe₅ led to the formation of the zwitterions (fulvalene)[W(CO)₃^-][Fe(CO)PR₃⁺] (107, R = P(OMe)₃; 108, R = PMe₃). Compound 31 also displayed unique behavior with different reducing agents, as the monosubstituted zwitterion (fulvalene)[W(CO)₃^-][Ru(CO)₂(PMe₃⁺] was obtained when 97 was used while the disubstituted complex (fulvalene) [W(CO)₃^-] [Ru(CO)(PMe₃)₂⁺] was produced when Cp*Fe(C₆Me₆) was the catalyst. Potential synthetic routes to quatercyclopentadienyl complexes were also explored. Various attempts to couple heterobimetallic fulvalene compounds proved to be unsuccessful. 138 refs.

Lecithin Complex

African Journals Online (AJOL)

1Department of Food Science and Engineering, Xinyang College of Agriculture and ... Results: The UV and IR spectra of the complex showed an additive effect of polydatin-lecithin, in which .... Monochromatic Cu Ka radiation (wavelength =.

Complexity in Picture Books

Science.gov (United States)

Sierschynski, Jarek; Louie, Belinda; Pughe, Bronwyn

2015-01-01

One of the key requirements of Common Core State Standards (CCSS) in English Language Arts is that students are able to read and access complex texts across all grade levels. The CCSS authors emphasize both the limitations and lack of accuracy in the current CCSS model of text complexity, calling for the development of new frameworks. In response…

Maximizing information exchange between complex networks

International Nuclear Information System (INIS)

West, Bruce J.; Geneston, Elvis L.; Grigolini, Paolo

2008-01-01

Science is not merely the smooth progressive interaction of hypothesis, experiment and theory, although it sometimes has that form. More realistically the scientific study of any given complex phenomenon generates a number of explanations, from a variety of perspectives, that eventually requires synthesis to achieve a deep level of insight and understanding. One such synthesis has created the field of out-of-equilibrium statistical physics as applied to the understanding of complex dynamic networks. Over the past forty years the concept of complexity has undergone a metamorphosis. Complexity was originally seen as a consequence of memory in individual particle trajectories, in full agreement with a Hamiltonian picture of microscopic dynamics and, in principle, macroscopic dynamics could be derived from the microscopic Hamiltonian picture. The main difficulty in deriving macroscopic dynamics from microscopic dynamics is the need to take into account the actions of a very large number of components. The existence of events such as abrupt jumps, considered by the conventional continuous time random walk approach to describing complexity was never perceived as conflicting with the Hamiltonian view. Herein we review many of the reasons why this traditional Hamiltonian view of complexity is unsatisfactory. We show that as a result of technological advances, which make the observation of single elementary events possible, the definition of complexity has shifted from the conventional memory concept towards the action of non-Poisson renewal events. We show that the observation of crucial processes, such as the intermittent fluorescence of blinking quantum dots as well as the brain's response to music, as monitored by a set of electrodes attached to the scalp, has forced investigators to go beyond the traditional concept of complexity and to establish closer contact with the nascent field of complex networks. Complex networks form one of the most challenging areas of modern

Maximizing information exchange between complex networks

Science.gov (United States)

West, Bruce J.; Geneston, Elvis L.; Grigolini, Paolo

2008-10-01

Science is not merely the smooth progressive interaction of hypothesis, experiment and theory, although it sometimes has that form. More realistically the scientific study of any given complex phenomenon generates a number of explanations, from a variety of perspectives, that eventually requires synthesis to achieve a deep level of insight and understanding. One such synthesis has created the field of out-of-equilibrium statistical physics as applied to the understanding of complex dynamic networks. Over the past forty years the concept of complexity has undergone a metamorphosis. Complexity was originally seen as a consequence of memory in individual particle trajectories, in full agreement with a Hamiltonian picture of microscopic dynamics and, in principle, macroscopic dynamics could be derived from the microscopic Hamiltonian picture. The main difficulty in deriving macroscopic dynamics from microscopic dynamics is the need to take into account the actions of a very large number of components. The existence of events such as abrupt jumps, considered by the conventional continuous time random walk approach to describing complexity was never perceived as conflicting with the Hamiltonian view. Herein we review many of the reasons why this traditional Hamiltonian view of complexity is unsatisfactory. We show that as a result of technological advances, which make the observation of single elementary events possible, the definition of complexity has shifted from the conventional memory concept towards the action of non-Poisson renewal events. We show that the observation of crucial processes, such as the intermittent fluorescence of blinking quantum dots as well as the brain’s response to music, as monitored by a set of electrodes attached to the scalp, has forced investigators to go beyond the traditional concept of complexity and to establish closer contact with the nascent field of complex networks. Complex networks form one of the most challenging areas of

Maximizing information exchange between complex networks

Energy Technology Data Exchange (ETDEWEB)

West, Bruce J. [Mathematical and Information Science, Army Research Office, Research Triangle Park, NC 27708 (United States); Physics Department, Duke University, Durham, NC 27709 (United States)], E-mail: bwest@nc.rr.com; Geneston, Elvis L. [Center for Nonlinear Science, University of North Texas, P.O. Box 311427, Denton, TX 76203-1427 (United States); Physics Department, La Sierra University, 4500 Riverwalk Parkway, Riverside, CA 92515 (United States); Grigolini, Paolo [Center for Nonlinear Science, University of North Texas, P.O. Box 311427, Denton, TX 76203-1427 (United States); Istituto di Processi Chimico Fisici del CNR, Area della Ricerca di Pisa, Via G. Moruzzi, 56124, Pisa (Italy); Dipartimento di Fisica ' E. Fermi' Universita' di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy)

2008-10-15

Science is not merely the smooth progressive interaction of hypothesis, experiment and theory, although it sometimes has that form. More realistically the scientific study of any given complex phenomenon generates a number of explanations, from a variety of perspectives, that eventually requires synthesis to achieve a deep level of insight and understanding. One such synthesis has created the field of out-of-equilibrium statistical physics as applied to the understanding of complex dynamic networks. Over the past forty years the concept of complexity has undergone a metamorphosis. Complexity was originally seen as a consequence of memory in individual particle trajectories, in full agreement with a Hamiltonian picture of microscopic dynamics and, in principle, macroscopic dynamics could be derived from the microscopic Hamiltonian picture. The main difficulty in deriving macroscopic dynamics from microscopic dynamics is the need to take into account the actions of a very large number of components. The existence of events such as abrupt jumps, considered by the conventional continuous time random walk approach to describing complexity was never perceived as conflicting with the Hamiltonian view. Herein we review many of the reasons why this traditional Hamiltonian view of complexity is unsatisfactory. We show that as a result of technological advances, which make the observation of single elementary events possible, the definition of complexity has shifted from the conventional memory concept towards the action of non-Poisson renewal events. We show that the observation of crucial processes, such as the intermittent fluorescence of blinking quantum dots as well as the brain's response to music, as monitored by a set of electrodes attached to the scalp, has forced investigators to go beyond the traditional concept of complexity and to establish closer contact with the nascent field of complex networks. Complex networks form one of the most challenging areas of

COULCC: A continued-fraction algorithm for Coulomb functions of complex order with complex arguments

International Nuclear Information System (INIS)

Thompson, I.J.; Barnett, A.R.

1985-01-01

The routine COULCC calculates both the oscillating and the exponentially varying Coulomb wave functions, and their radial derivations, for complex eta(Sommerfeld parameter), complex energies and complex angular momenta. The functions for uncharged scattering (spherical Bessels) and cylindrical Bessel functions are special cases which are more easily solved. Two linearly independent solutions are found, in general, to the differential equation f''(x)+g(x)f(x)=0, where g(x) has x 0 , x -1 and x -2 terms, with coefficients 1, -2eta and -lambda(lambda+1), respectively. (orig.)

Cumulative complexity: a functional, patient-centered model of patient complexity can improve research and practice.

Science.gov (United States)

Shippee, Nathan D; Shah, Nilay D; May, Carl R; Mair, Frances S; Montori, Victor M

2012-10-01

To design a functional, patient-centered model of patient complexity with practical applicability to analytic design and clinical practice. Existing literature on patient complexity has mainly identified its components descriptively and in isolation, lacking clarity as to their combined functions in disrupting care or to how complexity changes over time. The authors developed a cumulative complexity model, which integrates existing literature and emphasizes how clinical and social factors accumulate and interact to complicate patient care. A narrative literature review is used to explicate the model. The model emphasizes a core, patient-level mechanism whereby complicating factors impact care and outcomes: the balance between patient workload of demands and patient capacity to address demands. Workload encompasses the demands on the patient's time and energy, including demands of treatment, self-care, and life in general. Capacity concerns ability to handle work (e.g., functional morbidity, financial/social resources, literacy). Workload-capacity imbalances comprise the mechanism driving patient complexity. Treatment and illness burdens serve as feedback loops, linking negative outcomes to further imbalances, such that complexity may accumulate over time. With its components largely supported by existing literature, the model has implications for analytic design, clinical epidemiology, and clinical practice. Copyright © 2012 Elsevier Inc. All rights reserved.

Reduction of Subjective and Objective System Complexity

Science.gov (United States)

Watson, Michael D.

2015-01-01

Occam's razor is often used in science to define the minimum criteria to establish a physical or philosophical idea or relationship. Albert Einstein is attributed the saying "everything should be made as simple as possible, but not simpler". These heuristic ideas are based on a belief that there is a minimum state or set of states for a given system or phenomena. In looking at system complexity, these heuristics point us to an idea that complexity can be reduced to a minimum. How then, do we approach a reduction in complexity? Complexity has been described as a subjective concept and an objective measure of a system. Subjective complexity is based on human cognitive comprehension of the functions and inter relationships of a system. Subjective complexity is defined by the ability to fully comprehend the system. Simplifying complexity, in a subjective sense, is thus gaining a deeper understanding of the system. As Apple's Jonathon Ive has stated," It's not just minimalism or the absence of clutter. It involves digging through the depth of complexity. To be truly simple, you have to go really deep". Simplicity is not the absence of complexity but a deeper understanding of complexity. Subjective complexity, based on this human comprehension, cannot then be discerned from the sociological concept of ignorance. The inability to comprehend a system can be either a lack of knowledge, an inability to understand the intricacies of a system, or both. Reduction in this sense is based purely on a cognitive ability to understand the system and no system then may be truly complex. From this view, education and experience seem to be the keys to reduction or eliminating complexity. Objective complexity, is the measure of the systems functions and interrelationships which exist independent of human comprehension. Jonathon Ive's statement does not say that complexity is removed, only that the complexity is understood. From this standpoint, reduction of complexity can be approached

Increasing complexity with quantum physics.

Science.gov (United States)

Anders, Janet; Wiesner, Karoline

2011-09-01

We argue that complex systems science and the rules of quantum physics are intricately related. We discuss a range of quantum phenomena, such as cryptography, computation and quantum phases, and the rules responsible for their complexity. We identify correlations as a central concept connecting quantum information and complex systems science. We present two examples for the power of correlations: using quantum resources to simulate the correlations of a stochastic process and to implement a classically impossible computational task.

Rhodium complexes as therapeutic agents.

Science.gov (United States)

Ma, Dik-Lung; Wang, Modi; Mao, Zhifeng; Yang, Chao; Ng, Chan-Tat; Leung, Chung-Hang

2016-02-21

The landscape of inorganic medicinal chemistry has been dominated by the investigation of platinum, and to a lesser extent ruthenium, complexes over the past few decades. Recently, complexes based on other metal centers such as rhodium have attracted attention due to their tunable chemical and biological properties as well as distinct mechanisms of action. This perspective highlights recent examples of rhodium complexes that show diverse biological activities against various targets, including enzymes and protein-protein interactions.

Stability constants of scandium complexes, 1

International Nuclear Information System (INIS)

Itoh, Hisako; Itoh, Naomi; Suzuki, Yasuo

1984-01-01

The stability constants of scandium complexes with some carboxylate ligands were determined potentiometrically at 25.0 and 40.0 0 C and at an ionic strength of 0.10 with potassium nitrate as supporting electrolyte. The constants of the scandium complexes were appreciably greater than those of the corresponding lanthanoid complexes, as expected. The changes in free energy, enthalpy, and entropy for the formation of the scandium complexes were calculated from the stability constants at two temperatures. (author)

Increase of Organization in Complex Systems

OpenAIRE

Georgiev, Georgi Yordanov; Daly, Michael; Gombos, Erin; Vinod, Amrit; Hoonjan, Gajinder

2013-01-01

Measures of complexity and entropy have not converged to a single quantitative description of levels of organization of complex systems. The need for such a measure is increasingly necessary in all disciplines studying complex systems. To address this problem, starting from the most fundamental principle in Physics, here a new measure for quantity of organization and rate of self-organization in complex systems based on the principle of least (stationary) action is applied to a model system -...

Early days in complex dynamics a history of complex dynamics in one variable during 1906-1942

CERN Document Server

Alexander, Daniel S; Rosa, Alessandro

2011-01-01

The theory of complex dynamics, whose roots lie in 19th-century studies of the iteration of complex function conducted by Kœnigs, Schröder, and others, flourished remarkably during the first half of the 20th century, when many of the central ideas and techniques of the subject developed. This book by Alexander, Iavernaro, and Rosa paints a robust picture of the field of complex dynamics between 1906 and 1942 through detailed discussions of the work of Fatou, Julia, Siegel, and several others. A recurrent theme of the authors' treatment is the center problem in complex dynamics. They present its complete history during this period and, in so doing, bring out analogies between complex dynamics and the study of differential equations, in particular, the problem of stability in Hamiltonian systems. Among these analogies are the use of iteration and problems involving small divisors which the authors examine in the work of Poincaré and others, linking them to complex dynamics, principally via the work of Samuel...

Complexity in White Noise Analysis

Science.gov (United States)

Hida, Takeyuki

We restrict our attention to random complex systems and discuss degree their degree of complexity based on a white noise. The white noise is realized as the time derivative of a Brownian motion B(t), and denoted by Ḃ(t). The collection {Ḃ(t)}, is a system of idealized elementary variables and at the same time the system is a stochastic representation of the time t, in other words it is time-oriented. Having expressed the given evolutional random phenomena in question in terms of the Ḃ(t), we introduce the notion of spectral multiplicity, which describes how much the phenomena are complex. The multiplicity is the number of cyclic subspaces that are spanned by the given random phenomena. Each cyclic subspace has further structure. Typical property is multiple Markov property, although this property appears only particular cases. As a related property, in fact as a characteristic of a complex system, one can speak of the time reversibility and irreversibility of certain random phenomena in terms of the white noise. We expect an irreversible random complex system may be decomposed into reversible systems.

On synchronisation of a class of complex chaotic systems with complex unknown parameters via integral sliding mode control

Science.gov (United States)

Tirandaz, Hamed; Karami-Mollaee, Ali

2018-06-01

Chaotic systems demonstrate complex behaviour in their state variables and their parameters, which generate some challenges and consequences. This paper presents a new synchronisation scheme based on integral sliding mode control (ISMC) method on a class of complex chaotic systems with complex unknown parameters. Synchronisation between corresponding states of a class of complex chaotic systems and also convergence of the errors of the system parameters to zero point are studied. The designed feedback control vector and complex unknown parameter vector are analytically achieved based on the Lyapunov stability theory. Moreover, the effectiveness of the proposed methodology is verified by synchronisation of the Chen complex system and the Lorenz complex systems as the leader and the follower chaotic systems, respectively. In conclusion, some numerical simulations related to the synchronisation methodology is given to illustrate the effectiveness of the theoretical discussions.

Complexity, Modeling, and Natural Resource Management

Directory of Open Access Journals (Sweden)

Paul Cilliers

2013-09-01

Full Text Available This paper contends that natural resource management (NRM issues are, by their very nature, complex and that both scientists and managers in this broad field will benefit from a theoretical understanding of complex systems. It starts off by presenting the core features of a view of complexity that not only deals with the limits to our understanding, but also points toward a responsible and motivating position. Everything we do involves explicit or implicit modeling, and as we can never have comprehensive access to any complex system, we need to be aware both of what we leave out as we model and of the implications of the choice of our modeling framework. One vantage point is never sufficient, as complexity necessarily implies that multiple (independent conceptualizations are needed to engage the system adequately. We use two South African cases as examples of complex systems - restricting the case narratives mainly to the biophysical domain associated with NRM issues - that make the point that even the behavior of the biophysical subsystems themselves are already complex. From the insights into complex systems discussed in the first part of the paper and the lessons emerging from the way these cases have been dealt with in reality, we extract five interrelated generic principles for practicing science and management in complex NRM environments. These principles are then further elucidated using four further South African case studies - organized as two contrasting pairs - and now focusing on the more difficult organizational and social side, comparing the human organizational endeavors in managing such systems.

Mapping on complex neutrosophic soft expert sets

Science.gov (United States)

Al-Quran, Ashraf; Hassan, Nasruddin

2018-04-01

We introduce the mapping on complex neutrosophic soft expert sets. Further, we investigated the basic operations and other related properties of complex neutrosophic soft expert image and complex neutrosophic soft expert inverse image of complex neutrosophic soft expert sets.

Electrolytic conductivity of synthetic organomineral complexes

Directory of Open Access Journals (Sweden)

Ksiezopolska Alicja

2005-01-01

Full Text Available The mechanism of the formation of organomineral complexes in soils is very complex and still little known. Examination of the complexes in unaltered form, as isolated from the soil, is very difficult due to the dispersing effect of all extraction agents which break the complexes up, destroying their natural properties. It is much easier to perform most of the tests on preparations of organomineral complexes obtained under laboratory conditions. This paper is concerned with model research on the formation of synthetic complexes of humic acids with minerals: Na-montmorillonite, mica, kaolinite at various pH values (3-7 and in the presence of aluminum ions. The aim of the research was to develop an optimum reaction of suspension for the synthesis of organomineral complexes, to study the role of aluminum ions, and to attempt to determine the degree of their complexity on the basis of the electrolytic conductivity (EC. An important influence of the suspension pH value on the value of EC was observed. The greatest correlation was found in the organomineral preparations with kaolinite and with aluminum (r = 0.93***. Generally, it can be stated that the degree of reaction of humic acids with minerals depended most of all on the type of mineral, on the pH value, and on the presence of aluminum.

Analysis of nanoparticle biomolecule complexes.

Science.gov (United States)

Gunnarsson, Stefán B; Bernfur, Katja; Mikkelsen, Anders; Cedervall, Tommy

2018-03-01

Nanoparticles exposed to biological fluids adsorb biomolecules on their surface forming a biomolecular corona. This corona determines, on a molecular level, the interactions and impact the newly formed complex has on cells and organisms. The corona formation as well as the physiological and toxicological relevance are commonly investigated. However, an acknowledged but rarely addressed problem in many fields of nanobiotechnology is aggregation and broadened size distribution of nanoparticles following their interactions with the molecules of biological fluids. In blood serum, TiO 2 nanoparticles form complexes with a size distribution from 30 nm to more than 500 nm. In this study we have separated these complexes, with good resolution, using preparative centrifugation in a sucrose gradient. Two main apparent size populations were obtained, a fast sedimenting population of complexes that formed a pellet in the preparative centrifugation tube, and a slow sedimenting complex population still suspended in the gradient after centrifugation. Concentration and surface area dependent differences are found in the biomolecular corona between the slow and fast sedimenting fractions. There are more immunoglobulins, lipid binding proteins, and lipid-rich complexes at higher serum concentrations. Sedimentation rate and the biomolecular corona are important factors for evaluating any experiment including nanoparticle exposure. Our results show that traditional description of nanoparticles in biological fluids is an oversimplification and that more thorough characterisations are needed.

The multitalented Mediator complex.

Science.gov (United States)

Carlsten, Jonas O P; Zhu, Xuefeng; Gustafsson, Claes M

2013-11-01

The Mediator complex is needed for regulated transcription of RNA polymerase II (Pol II)-dependent genes. Initially, Mediator was only seen as a protein bridge that conveyed regulatory information from enhancers to the promoter. Later studies have added many other functions to the Mediator repertoire. Indeed, recent findings show that Mediator influences nearly all stages of transcription and coordinates these events with concomitant changes in chromatin organization. We review the multitude of activities associated with Mediator and discuss how this complex coordinates transcription with other cellular events. We also discuss the inherent difficulties associated with in vivo characterization of a coactivator complex that can indirectly affect diverse cellular processes via changes in gene transcription. Copyright © 2013 Elsevier Ltd. All rights reserved.

Convergence of Batch Split-Complex Backpropagation Algorithm for Complex-Valued Neural Networks

Directory of Open Access Journals (Sweden)

Huisheng Zhang

2009-01-01

Full Text Available The batch split-complex backpropagation (BSCBP algorithm for training complex-valued neural networks is considered. For constant learning rate, it is proved that the error function of BSCBP algorithm is monotone during the training iteration process, and the gradient of the error function tends to zero. By adding a moderate condition, the weights sequence itself is also proved to be convergent. A numerical example is given to support the theoretical analysis.

The sleeping brain as a complex system.

Science.gov (United States)

Olbrich, Eckehard; Achermann, Peter; Wennekers, Thomas

2011-10-13

'Complexity science' is a rapidly developing research direction with applications in a multitude of fields that study complex systems consisting of a number of nonlinear elements with interesting dynamics and mutual interactions. This Theme Issue 'The complexity of sleep' aims at fostering the application of complexity science to sleep research, because the brain in its different sleep stages adopts different global states that express distinct activity patterns in large and complex networks of neural circuits. This introduction discusses the contributions collected in the present Theme Issue. We highlight the potential and challenges of a complex systems approach to develop an understanding of the brain in general and the sleeping brain in particular. Basically, we focus on two topics: the complex networks approach to understand the changes in the functional connectivity of the brain during sleep, and the complex dynamics of sleep, including sleep regulation. We hope that this Theme Issue will stimulate and intensify the interdisciplinary communication to advance our understanding of the complex dynamics of the brain that underlies sleep and consciousness.

Complexity-aware high efficiency video coding

CERN Document Server

Correa, Guilherme; Agostini, Luciano; Cruz, Luis A da Silva

2016-01-01

This book discusses computational complexity of High Efficiency Video Coding (HEVC) encoders with coverage extending from the analysis of HEVC compression efficiency and computational complexity to the reduction and scaling of its encoding complexity. After an introduction to the topic and a review of the state-of-the-art research in the field, the authors provide a detailed analysis of the HEVC encoding tools compression efficiency and computational complexity.  Readers will benefit from a set of algorithms for scaling the computational complexity of HEVC encoders, all of which take advantage from the flexibility of the frame partitioning structures allowed by the standard.  The authors also provide a set of early termination methods based on data mining and machine learning techniques, which are able to reduce the computational complexity required to find the best frame partitioning structures. The applicability of the proposed methods is finally exemplified with an encoding time control system that emplo...

8th Conference on Complex Networks

CERN Document Server

Menezes, Ronaldo; Sinatra, Roberta; Zlatic, Vinko

2017-01-01

This book collects the works presented at the 8th International Conference on Complex Networks (CompleNet) 2017 in Dubrovnik, Croatia, on March 21-24, 2017. CompleNet aims at bringing together researchers and practitioners working in areas related to complex networks. The past two decades has witnessed an exponential increase in the number of publications within this field. From biological systems to computer science, from economic to social systems, complex networks are becoming pervasive in many fields of science. It is this interdisciplinary nature of complex networks that CompleNet aims at addressing. The last decades have seen the emergence of complex networks as the language with which a wide range of complex phenomena in fields as diverse as physics, computer science, and medicine (to name a few) can be properly described and understood. This book provides a view of the state-of-the-art in this dynamic field and covers topics such as network controllability, social structure, online behavior, recommend...

Anti-synchronization between different chaotic complex systems

International Nuclear Information System (INIS)

Liu Ping; Liu Shutang

2011-01-01

Many studies on the anti-synchronization of nonlinear real dynamic systems have been carried out, whereas the anti-synchronization of chaotic complex systems has not been studied extensively. In this work, the anti-synchronization between a new chaotic complex system and a complex Lorenz system and that between a new chaotic complex system and a complex Lue system were separately investigated by active control and nonlinear control methods, and explicit expressions were derived for the controllers that are used to achieve the anti-synchronization of chaotic complex systems. These expressions were tested numerically and excellent agreement was found. Concerning the new chaotic complex system, we discuss its dynamical properties including dissipation, chaotic behavior, fixed points, and their stability and invariance.

Complexity measures of music

Science.gov (United States)

Pease, April; Mahmoodi, Korosh; West, Bruce J.

2018-03-01

We present a technique to search for the presence of crucial events in music, based on the analysis of the music volume. Earlier work on this issue was based on the assumption that crucial events correspond to the change of music notes, with the interesting result that the complexity index of the crucial events is mu ~ 2, which is the same inverse power-law index of the dynamics of the brain. The search technique analyzes music volume and confirms the results of the earlier work, thereby contributing to the explanation as to why the brain is sensitive to music, through the phenomenon of complexity matching. Complexity matching has recently been interpreted as the transfer of multifractality from one complex network to another. For this reason we also examine the mulifractality of music, with the observation that the multifractal spectrum of a computer performance is significantly narrower than the multifractal spectrum of a human performance of the same musical score. We conjecture that although crucial events are demonstrably important for information transmission, they alone are not suficient to define musicality, which is more adequately measured by the multifractality spectrum.

The kinesin–tubulin complex: considerations in structural and functional complexity

Directory of Open Access Journals (Sweden)

Olmsted ZT

2015-02-01

Full Text Available Zachary T Olmsted, Andrew G Colliver, Janet L Paluh State University of New York Polytechnic Institute, Colleges of Nanoscale Science and Engineering, College of Nanoscale Science, Nanobioscience Constellation, Albany, NY, USA Abstract: The ability of cells to respond to external cues by appropriately manipulating their internal environment requires a dynamic microtubule cytoskeleton that is facilitated by associated kinesin motor interactions. The evolutionary adaptations of kinesins and tubulins when merged generate a highly adaptable communication and infrastructure cellular network that is important to understanding specialized cell functions, human disease, and disease therapies. Here, we review the state of the field in the complex relationship of kinesin–tubulin interactions. We propose 12 mechanistic specializations of kinesins. In one category, referred to as sortability, we describe how kinesin interactions with tubulin isoforms, isotypes, or posttranslationally modified tubulins contribute to diverse cellular roles. Fourteen kinesin families have previously been described. Here, we illustrate the great depth of functional complexity that is possible in members within a single kinesin family by mechanistic specialization through discussion of the well-studied Kinesin-14 family. This includes new roles of Kinesin-14 in regulating supramolecular structures such as the microtubule-organizing center γ-tubulin ring complex of centrosomes. We next explore the value of an improved mechanistic understanding of kinesin–tubulin interactions in regard to human development, disease mechanisms, and improving treatments that target kinesin–tubulin complexes. The ability to combine the current kinesin nomenclature along with a more precisely defined kinesin and tubulin molecular toolbox is needed to support more detailed exploration of kinesin–tubulin interaction mechanisms including functional uniqueness, redundancy, or adaptations to new

Complex function theory

CERN Document Server

Sarason, Donald

2007-01-01

Complex Function Theory is a concise and rigorous introduction to the theory of functions of a complex variable. Written in a classical style, it is in the spirit of the books by Ahlfors and by Saks and Zygmund. Being designed for a one-semester course, it is much shorter than many of the standard texts. Sarason covers the basic material through Cauchy's theorem and applications, plus the Riemann mapping theorem. It is suitable for either an introductory graduate course or an undergraduate course for students with adequate preparation. The first edition was published with the title Notes on Co

Superspace de Rham complex and relative cohomology

Energy Technology Data Exchange (ETDEWEB)

III, William D. Linch; Randall, Stephen [Center for String and Particle Theory,Department of Physics, University of Maryland at College Park,College Park, MD 20742-4111 (United States)

2015-09-28

We investigate the super-de Rham complex of five-dimensional superforms with N=1 supersymmetry. By introducing a free supercommutative algebra of auxiliary variables, we show that this complex is equivalent to the Chevalley-Eilenberg complex of the translation supergroup with values in superfields. Each cocycle of this complex is defined by a Lorentz- and iso-spin-irreducible superfield subject to a set of constraints. Restricting to constant coefficients results in a subcomplex in which components of the cocycles are coboundaries while the constraints on the defining superfields span the cohomology. This reduces the computation of all of the superspace Bianchi identities to a single linear algebra problem the solution of which implies new features not present in the standard four-dimensional, N=1 complex. These include splitting/joining in the complex and the existence of cocycles that do not correspond to irreducible supermultiplets of closed differential forms. Interpreting the five-dimensional de Rham complex as arising from dimensional reduction from the six-dimensional complex, we find a second five-dimensional complex associated to the relative de Rham complex of the embedding of the latter in the former. This gives rise to a second source of closed differential forms previously attributed to the phenomenon called “Weyl triviality”.

Critical Fluctuations in Spatial Complex Networks

Science.gov (United States)

Bradde, Serena; Caccioli, Fabio; Dall'Asta, Luca; Bianconi, Ginestra

2010-05-01

An anomalous mean-field solution is known to capture the nontrivial phase diagram of the Ising model in annealed complex networks. Nevertheless, the critical fluctuations in random complex networks remain mean field. Here we show that a breakdown of this scenario can be obtained when complex networks are embedded in geometrical spaces. Through the analysis of the Ising model on annealed spatial networks, we reveal, in particular, the spectral properties of networks responsible for critical fluctuations and we generalize the Ginsburg criterion to complex topologies.

Reliability of large and complex systems

CERN Document Server

Kolowrocki, Krzysztof

2014-01-01

Reliability of Large and Complex Systems, previously titled Reliability of Large Systems, is an innovative guide to the current state and reliability of large and complex systems. In addition to revised and updated content on the complexity and safety of large and complex mechanisms, this new edition looks at the reliability of nanosystems, a key research topic in nanotechnology science. The author discusses the importance of safety investigation of critical infrastructures that have aged or have been exposed to varying operational conditions. This reference provides an asympt

Holographic complexity for time-dependent backgrounds

Energy Technology Data Exchange (ETDEWEB)

Momeni, Davood, E-mail: davoodmomeni78@gmail.com [Eurasian International Center for Theoretical Physics and Department of General Theoretical Physics, Eurasian National University, Astana 010008 (Kazakhstan); Faizal, Mir, E-mail: mirfaizalmir@googlemail.com [Irving K. Barber School of Arts and Sciences, University of British Columbia, Okanagan, 3333 University Way, Kelowna, British Columbia V1V 1V7 (Canada); Department of Physics and Astronomy, University of Lethbridge, Lethbridge, Alberta, T1K 3M4 (Canada); Bahamonde, Sebastian, E-mail: sebastian.beltran.14@ucl.ac.uk [Department of Mathematics, University College London, Gower Street, London, WC1E 6BT (United Kingdom); Myrzakulov, Ratbay [Eurasian International Center for Theoretical Physics and Department of General Theoretical Physics, Eurasian National University, Astana 010008 (Kazakhstan)

2016-11-10

In this paper, we will analyze the holographic complexity for time-dependent asymptotically AdS geometries. We will first use a covariant zero mean curvature slicing of the time-dependent bulk geometries, and then use this co-dimension one spacelike slice of the bulk spacetime to define a co-dimension two minimal surface. The time-dependent holographic complexity will be defined using the volume enclosed by this minimal surface. This time-dependent holographic complexity will reduce to the usual holographic complexity for static geometries. We will analyze the time-dependence as a perturbation of the asymptotically AdS geometries. Thus, we will obtain time-dependent asymptotically AdS geometries, and we will calculate the holographic complexity for such time-dependent geometries.

The complexity paradigm in management reconceptualizing

Directory of Open Access Journals (Sweden)

Petrović Slavica P.

2005-01-01

Full Text Available Chaos and complexity theory is a special, functionalist systems approach to dealing with complex, dynamic, nonlinear systems. Through treating organizations as complex, with their environments coevolving, nonlinear systems, complexity theory is aimed at creative research of their erratic nature. When an organization is in a state of bounded instability, at the edge of chaos, order and disorder are intertwined, its behavior is irregular and unpredictable but has some pattern. According to the complexity paradigm organizations have to strive to avoid the equilibrium states of stability and instability. They have instead to strive to remain in a state of bounded instability, at the edge of chaos, where they are able to display their full potential for creativity and innovation.

Amphotericin B Lipid Complex Injection

Science.gov (United States)

Amphotericin B lipid complex injection is used to treat serious, possibly life-threatening fungal infections in people who did ... respond or are unable to tolerate conventional amphotericin B therapy. Amphotericin B lipid complex injection is in ...

Implicit computational complexity and compilers

DEFF Research Database (Denmark)

Rubiano, Thomas

Complexity theory helps us predict and control resources, usually time and space, consumed by programs. Static analysis on specific syntactic criterion allows us to categorize some programs. A common approach is to observe the program’s data’s behavior. For instance, the detection of non...... evolution and a lot of research came from this theory. Until now, these implicit complexity theories were essentially applied on more or less toy languages. This thesis applies implicit computational complexity methods into “real life” programs by manipulating intermediate representation languages...

Conversation, coupling and complexity

DEFF Research Database (Denmark)

Fusaroli, Riccardo; Abney, Drew; Bahrami, Bahador

We investigate the linguistic co-construction of interpersonal synergies. By applying a measure of coupling between complex systems to an experimentally elicited corpus of joint decision dialogues, we show that interlocutors’ linguistic behavior displays increasing signature of multi-scale coupling......, known as complexity matching, over the course of interaction. Furthermore, we show that stronger coupling corresponds with more effective interaction, as measured by collective task performance....

On the interconnection of stable protein complexes: inter-complex hubs and their conservation in Saccharomyces cerevisiae and Homo sapiens networks.

Science.gov (United States)

Guerra, Concettina

2015-01-01

Protein complexes are key molecular entities that perform a variety of essential cellular functions. The connectivity of proteins within a complex has been widely investigated with both experimental and computational techniques. We developed a computational approach to identify and characterise proteins that play a role in interconnecting complexes. We computed a measure of inter-complex centrality, the crossroad index, based on disjoint paths connecting proteins in distinct complexes and identified inter-complex hubs as proteins with a high value of the crossroad index. We applied the approach to a set of stable complexes in Saccharomyces cerevisiae and in Homo sapiens. Just as done for hubs, we evaluated the topological and biological properties of inter-complex hubs addressing the following questions. Do inter-complex hubs tend to be evolutionary conserved? What is the relation between crossroad index and essentiality? We found a good correlation between inter-complex hubs and both evolutionary conservation and essentiality.

Flow assurance : complex phase behavior and complex work requires confidence and vigilance

Energy Technology Data Exchange (ETDEWEB)

Brown, L.D. [ConocoPhillips, Major Projects, Advanced Integrated Simulation, Houston, TX (United States)

2008-07-01

Petroleum exploration and development projects and operations increasingly rely on flow assurance definition. Flow assurance is an integrating discipline as it follows the fluid from the reservoir to the market. Flow assurance works across complex technical and non-technical interfaces, including the reservoir, well completions, operation processes, project management, physical/organic chemistry, fluid mechanics, chemical engineering, mechanical engineering and corrosion. The phase behaviour in real fluids also has complex interfaces. The understanding and management of flow assurance of complex phase behaviour must be well communicated in order to enable proper selection, execution, and operation of development concepts designed to manage successful production within the fluid's phase behaviour. Simulation tools facilitate the translation of science into engineering. Academic, industrial, and field research is the core of these tools. The author cautioned that vigilance is required to assist and identify the right time to move innovation into the core tools.

Social complexity parallels vocal complexity: a comparison of three nonhuman primate species

Directory of Open Access Journals (Sweden)

Hélène eBOUCHET

2013-07-01

Full Text Available Social factors play a key role in the structuring of vocal repertoires at the individual level, notably in nonhuman primates. Some authors suggested that, at the species level too, social life may have driven the evolution of communicative complexity, but this has rarely been empirically tested. Here, we use a comparative approach to address this issue. We investigated vocal variability, at both the call type and the repertoire levels, in three forest-dwelling species of Cercopithecinae presenting striking differences in their social systems, in terms of social organization as well as social structure. We collected female call recordings from twelve De Brazza’s monkeys (Cercopithecus neglectus, six Campbell’s monkeys (Cercopithecus campbelli and seven red-capped mangabeys (Cercocebus torquatus housed in similar conditions. First, we noted that the level of acoustic variability and individual distinctiveness found in several call types was related to their importance in social functioning. Contact calls, essential to intra-group cohesion, were the most individually distinctive regardless of the species, while threat calls were more structurally variable in mangabeys, the most ‘despotic’ of our three species. Second, we found a parallel between the degree of complexity of the species’ social structure and the size, diversity, and usage of its vocal repertoire. Mangabeys (most complex social structure called twice as often as guenons and displayed the largest and most complex repertoire. De Brazza’s monkeys (simplest social structure displayed the smallest and simplest repertoire. Campbell’s monkeys displayed an intermediate pattern. Providing evidence of higher levels of vocal variability in species presenting a more complex social system, our results are in line with the theory of a social-vocal coevolution of communicative abilities, opening new perspectives for comparative research on the evolution of communication systems in

Generation of a haptoglobin-hemoglobin complex-specific Fab antibody blocking the binding of the complex to CD163

DEFF Research Database (Denmark)

Horn, Ivo R; Nielsen, Marianne Jensby; Madsen, Mette

2003-01-01

During intravascular hemolysis hemoglobin (Hb) binds to haptoglobin (Hp) leading to endocytosis of the complex by the macrophage receptor, CD163. In the present study, we used a phage-display Fab antibody strategy to explore if the complex formation between Hp and Hb leads to exposure of antigenic...... epitopes specific for the complex. By Hp-Hb-affinity screening of a phage-Fab library, we isolated a phage clone against the ligand complex. Surface plasmon resonance analyses of the Fab part expressed as a recombinant protein revealed a high affinity binding (KD = 3.9 nm) to Hp-Hb, whereas no binding...... was measured for non-complexed Hp or Hb. The Fab antibody completely inhibited the binding of 125I-labeled Hp-Hb complexes to CD163 and blocked their uptake in CD163-transfected cells. In conclusion, we have raised a receptor-blocking antibody specifically recognizing the Hp-Hb complex. In addition to provide...