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Sample records for ln extraction unusual

  1. Task-specific ionic liquids for An and Ln extraction: unusual speciation and extraction mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Billard, Isabelle; Jobin, Emilie; Ouadi, Ali; Gaillard, Clotilde [IPHC-DRS, Chimie nucleaire, 23 rue du Loess, BP28, 67037 Strasbourg cedex 2 (France)

    2008-07-01

    Extraction mechanisms of uranium by TBP (tributylphosphate) diluted in an ionic liquid BumimTf{sub 2}N (1-butyl-3-methyl-imidazolium bis(tri-fluoro-methyl-sulfonyl)imide) and by Task-Specific Ionic Liquids (TSILs) bearing a phosphoryl group were investigated. Great differences between these mechanisms and the one in the industrial solvent, dodecane, have been put in evidence. While in dodecane, the neutral species, UO{sub 2}(NO{sub 3}){sub 2}(TBP){sub 2}, is the major extracted complex, in BumimTf{sub 2}N and TSILs, at least two species are extracted with more or less similar proportions. Moreover, no uranyl species with two nitrates could be observed in these ionic liquids. Finally, the mechanisms vary from TBP in BumimTf{sub 2}N to TSILs. These results led to a so-to-say new kind of actinide chemistry. (authors)

  2. Observation of unusual topological surface states in half-Heusler compounds LnPtBi (Ln=Lu, Y).

    Science.gov (United States)

    Liu, Z K; Yang, L X; Wu, S-C; Shekhar, C; Jiang, J; Yang, H F; Zhang, Y; Mo, S-K; Hussain, Z; Yan, B; Felser, C; Chen, Y L

    2016-09-27

    Topological quantum materials represent a new class of matter with both exotic physical phenomena and novel application potentials. Many Heusler compounds, which exhibit rich emergent properties such as unusual magnetism, superconductivity and heavy fermion behaviour, have been predicted to host non-trivial topological electronic structures. The coexistence of topological order and other unusual properties makes Heusler materials ideal platform to search for new topological quantum phases (such as quantum anomalous Hall insulator and topological superconductor). By carrying out angle-resolved photoemission spectroscopy and ab initio calculations on rare-earth half-Heusler compounds LnPtBi (Ln=Lu, Y), we directly observe the unusual topological surface states on these materials, establishing them as first members with non-trivial topological electronic structure in this class of materials. Moreover, as LnPtBi compounds are non-centrosymmetric superconductors, our discovery further highlights them as promising candidates of topological superconductors.

  3. Synergistic extraction and separation of Am(III) and Ln(III) with HBMPPT-sulfoxide-HNO3-toluene system

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Some sulfoxides (petroleum sulfoxide -PSO, di-n-octyl sulfoxide -DOSO, etc.) were chosen as synergists to study the synergistic effect on the extraction re action with HBMPPT (4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione) for Am(III), and the synergistic separation for Am(III) and Ln(III). The synergistic extraction ability of PSO is greater than that of DOSO for Am(III). The synergistic complexes may be presented as Am. NO3.(BMPPT)2.HBMPPT.S2 (S indicates PSO or DOSO).

  4. Unusual extraction behaviour of crown ether when intercalated in bentonite

    Energy Technology Data Exchange (ETDEWEB)

    Sivaiah, M.V.; Krishna, R.M.; Murthy, G.S. [Andhra Univ., Nuclear Chemistry Section, Waltair (India); Venkatesan, K.A. [Indira Gandhi Centre for Atomic Research, Fuel Chemistry Div., Kapakkam (India); Sasidhar, P. [Atomic Energy Regulatory Board, Safety Research Institute, Kalpakkam (India)

    2005-04-01

    Di-cyclo-hexano-18-crown-6 (DCH18C6) has been intercalated in bentonite and the product, Ben-Crown, characterized by micro-elemental analysis, TG-DTA analysis, X-ray diffraction and IR spectroscopy. The permanent negative charge present in the bentonite layer has been exploited for more efficient extraction of cesium and strontium by Ben-Crown at nitric acid concentrations ({<=} 1.0 M) that gave only a meagre extraction when either DCH18C6 or bentonite alone were employed. The extraction of cesium and strontium has been investigated as a function of time, temperature, and the concentrations of nitric acid, metal ion and sodium nitrate. An unusual extraction phenomenon was observed at low concentrations of nitric acid ({<=} 1.0 M) in the absence of any organo-philic agents. Rapid extraction of the metal ion was followed by the establishment of an equilibrium, which occurred after 150 min. Distribution coefficients (K{sub d}) of 599 and 1007 ml g{sup -1} were obtained, respectively, for the extraction of cesium and strontium from 0.1 M nitric acid by Ben-Crown; K{sub d} decreased with an increase in the temperature or in the concentrations of nitric acid and sodium nitrate. The extraction data were fitted by the Langmuir adsorption model and the apparent experimental exchange capacity obtained by linear regression analysis was in good agreement with the amount of crown ether (0.22 mmol g{sup -1}) intercalated in bentonite. The enthalpy change ({delta}H{sup 0}) for the extraction of cesium and strontium was found to be exothermic. (authors)

  5. Alpha Radiolysis of Nuclear Solvent Extraction Ligands Used for An(III) and Ln(III) Separations

    Energy Technology Data Exchange (ETDEWEB)

    Mezyk, Stephen P. [California State Univ. (CalState), Long Beach, CA (United States); Mincher, Bruce J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Nilsson, Mikael [Univ. of California, Irvine, CA (United States)

    2016-08-01

    This document is the final report for the Nuclear Energy Universities Program (NEUP) grant 10-910 (DE-AC07-05ID14517) “Alpha Radiolysis of Nuclear Solvent Extraction Ligands used for An(III) and Ln(III) Separations”. The goal of this work was to obtain a quantitative understanding of the impacts of both low Linear Energy Transfer (LET, gamma-rays) and high LET (alpha particles) radiation chemistry occurring in future large-scale separations processes. This quantitative understanding of the major radiation effects on diluents and ligands is essential for optimal process implementation, and could result in significant cost savings in the future.

  6. ''114''-type nitrides LnAl(Si{sub 4-x}Al{sub x})N{sub 7}O{sub δ} with unusual [AlN{sub 6}] octahedral coordination

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Saifang; Ouyang, Xin [School of Materials Science and Technology, China University of Geosciences, Beijing (China); Department of Chemical and Materials Engineering, University of Auckland (New Zealand); Huang, Zhaohui; Fang, Minghao; Liu, Yan-gai [School of Materials Science and Technology, China University of Geosciences, Beijing (China); Cao, Peng; Gao, Wei [Department of Chemical and Materials Engineering, University of Auckland (New Zealand); Zujovic, Zoran; Soehnel, Tilo [School of Chemical Sciences, University of Auckland (New Zealand); Price, Jason R. [Australian Synchrotron, Clayton, VIC (Australia); Avdeev, Maxim [Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Que, Meidan [School of Electronic and Information Engineering, Xi' an Jiaotong University (China); Suzuki, Furitsu; Kido, Tsuyoshi; Kaji, Hironori [Institute for Chemical Research, Kyoto University (Japan)

    2017-03-27

    Aluminum-nitrogen six-fold octahedral coordination, [AlN{sub 6}], is unusual and has only been seen in the high-pressure rocksalt-type aluminum nitride or some complex compounds. Herein we report novel nitrides LnAl(Si{sub 4-x}Al{sub x})N{sub 7}O{sub δ} (Ln=La, Sm), the first inorganic compounds with [AlN{sub 6}] coordination prepared via non-high-pressure synthesis. Structure refinements of neutron powder diffraction and single-crystal X-ray diffraction data show that these compounds crystallize in the hexagonal Swedenborgite structure type with P6{sub 3}mc symmetry where Ln and Al atoms locate in anticuboctahedral and octahedral interstitials, respectively, between the triangular and Kagome layers of [SiN{sub 4}] tetrahedra. Solid-state NMR data of high-purity La-114 powders confirm the unusual [AlN{sub 6}] coordination. These compounds are the first examples of the ''33-114'' sub-type in the ''114'' family. The additional site for over-stoichiometric oxygen in the structure of 114-type compounds was also identified. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Liquid-liquid reductive extraction in molten fluoride salt/liquid aluminium as a core of process for the An/Ln group separation

    Energy Technology Data Exchange (ETDEWEB)

    Conocar, O

    2007-06-15

    This report concerns a pyrochemical process based on liquid-liquid extraction in a molten fluoride/liquid aluminium system as a core process for actinide (An)/lanthanide (Ln) group separation, studied at CEA. The basic and demonstrative experiments have established the feasibility of the An/Ln group separation in the molten fluoride/liquid aluminium system (U, Pu, Np, Am, Cm traces from Nd, Ce, Eu, Sm, Eu, La - An/Ln separation factors over 1000 - An recovery yield over 98 % in one batch). The main experimental efforts must now be targeted on the recovery of actinides from the Al matrix. A thermodynamic and bibliographical survey has been done. It shows that back-extraction in a molten chloride melt could be a promising technique for this purpose.

  8. Magnetic and magnetocaloric properties of an unusual family of carbonate-panelled [Ln(III)(6)Zn(III)(2)] cages.

    Science.gov (United States)

    Sethi, Waqas; Sanz, Sergio; Pedersen, Kasper S; Sørensen, Mikkel A; Nichol, Gary S; Lorusso, Giulia; Evangelisti, Marco; Brechin, Euan K; Piligkos, Stergios

    2015-06-14

    The reaction of the pro-ligand H4L, which combines the complementary phenolic oxime and diethanolamine moieties within the same organic framework, with Zn(NO3)2·6H2O and Ln(NO3)3·6H2O in a basic methanolic solution generates a family of isostructural heterometallic coordination compounds of general formula [Ln6Zn2(CO3)5(OH)(H2L)4(H3L)2(H4L)]NO3·xMeOH [Ln = Gd, x = 30 (), Ln = Dy, x = 32 (), Ln = Sm, x = 31 (), Ln = Eu, x = 29 (), Ln = Tb, x = 30 ()]. The octametallic skeleton of the cage describes a heavily distorted [Gd] octahedron capped on two faces by Zn(II) ions. The metal core is stabilised by a series of μ3- and μ4-CO3(2-) ions, originating from the serendipitous fixation of atmospheric CO2. The magnetic properties of all family members were examined via SQUID magnetometry, with the χMT product and VTVB data of the Gd analogue () being independently fitted by numerical diagonalisation to afford the same best-fit parameter JGd-Gd = -0.004 cm(-1). The MCE of complex was elucidated from specific heat data, with the magnetic entropy change reaching a value of 22.6 J kg(-1) K(-1) at T = 1.7 K, close to the maximum entropy value per mole expected from six Gd(III) spins (SGd = 7/2), 23.7 J kg(-1) K(-1).

  9. Experimental studies and tests on An(III)/Ln(III) separation using the TODGA extractant

    Energy Technology Data Exchange (ETDEWEB)

    Heres, Xavier; Sorel, Christian; Miguirditchian, Manuel; Cames, Beatrice; Hill, Clement; Bisel, Isabelle; Espinoux, Denis; Viallesoubranne, Carole; Baron, Pascal; Lorrain, Brigitte [CEA/DEN/MAR/DRCP, Marcoule, BP17171, 30207 Bagnols/Ceze (France)

    2009-06-15

    Minor actinide recycling by separation and transmutation is worldwide considered as one of the most promising strategies to reduce the inventory of radioactive waste, thus contributing to make nuclear energy more sustainable. One of the different options investigated at the CEA Marcoule and within the ACSEPT project (a European collaborative project partly funded by the 7. EURATOM Framework Program) to separate trivalent minor actinide (Am(III)-Cf(III)) from the fission and activation products contained in PUREX raffinates is the TODGA process, which consists in: 1. Co-extracting trivalent 4f and 5f elements from highly acidic PUREX raffinates by a mixture of TODGA (tetraoctyl-diglycolamide) and TBP (tributyl-phosphate), dissolved in HTP (hydrogenated tetra-propene). 2. Selectively stripping the trivalent minor actinides by a hydrophilic poly-aminocarboxylic acid used as a complexing agent in a buffered aqueous solution, while the trivalent lanthanides are kept in the organic solvent thanks to a sodium nitrate salting-out effect. 3. Stripping the lanthanides in a diluted nitric acid solution. The major difficulty of this TODGA separation process is to tune the pH in a very narrow range of operating conditions in the second step, because of the high sensitivity of the performances of the flow-sheet vs pH. This difficulty was however overcome. This paper describes the development of the TODGA process from experimental studies to hot test implementation in shielded cells of the ATALANTE facility, including (i) the optimization of the extraction system (both the formulation of the organic solvent and those of the aqueous scrubbing and stripping solutions), (ii) the implementation of a cold test in small scale mixer-settlers in the G1 facility (MARCEL loop), using a surrogate feed composed of major fission products, (iii) the validation of some steps of the process, using a surrogate feed, spiked with Am-241 and Eu-152, and similar laboratory contactors (medium activity

  10. Unusual stable isotope ratios in amino acid and carboxylic acid extracts from the Murchison meteorite

    Science.gov (United States)

    Epstein, S.; Krishnamurthy, R. V.; Cronin, J. R.; Pizzarello, S.; Yuen, G. U.

    1987-01-01

    The isotopic composition of hydrogen, nitrogen, and carbon in amino acid and monocarboxylic acid extracts from the Murchison meteorite has been determined. The unusually high D/H and N-15/N-14 ratios in the amino acid fraction are uniquely characteristic of known interstellar organic materials. The delta D value of the monocarboxylic acid fraction is lower but still consistent with an interstellar origin. These results confirm the extraterrestrial origin of both classes of compound and provide the first evidence suggesting a direct relationship between the massive organosynthesis occurring in interstellar clouds and the presence of prebiotic compounds in primitive planetary bodies.

  11. Syntheses, Structure, Magnetism, and Optical Properties of the Ordered Interlanthanide Copper Chalcogenides Ln{sub 2}YbCuQ{sub 5} (Ln = La, Ce, Pr, Nd, Sm; Q = S, Se): Evidence for Unusual Magnetic Ordering in Sm{sub 2}YbCuS{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Geng Bang; Choi, Eun Sang; Guertin, Robert P.; Booth, Corwin H.; Albrecht-Schmitt, Thomas E.

    2010-11-19

    Ln{sub 2}YbCuQ{sub 5} (Ln = La, Ce, Pr, Nd, Sm; Q = S, Se) have been prepared by direct reaction of the elements in Sb{sub 2}Q{sub 3} (Q = S, Se) fluxes at 900 °C. All compounds have been characterized by single-crystal X-ray diffraction methods and they are isotypic. The structure of Ln{sub 2}YbCuQ{sub 5} consists of one-dimensional {sup 1}{sub {infinity}} [YbCuQ{sub 5}]{sup 6-} ribbons extending along the b axis that are connected by larger Ln{sup 3+} ions. Each ribbon is constructed from two single chains of [YbQ{sub 6}] octahedra with one double chain of [CuQ{sub 5}] trigonal bipyramids in the middle. All three chains connect with each other via edge-sharing. There are two crystallographically unique Ln atoms, one octahedral Yb site, and two disordered Cu positions inside of distorted Q{sub 5} trigonal bipyramids. Both Ln atoms are surrounded by eight Q atoms in bicapped trigonal prisms. The magnetic properties of Ln{sub 2}YbCuQ{sub 5} have been characterized using magnetic susceptibility and heat capacity measurements, while their optical properties have been explored using UV-vis-NIR diffuse reflectance spectroscopy. Cesub 2}YbCuSe{sub 5}, La{sub 2}YbCuS{sub 5}, Ce{sub 2}YbCuS{sub 5}, and Pr{sub 2}YbCuS{sub 5} are Curie-Weiss paramagnets. La{sub 2}YbCuSe{sub 5} and Nd{sub 2}YbCuS{sub 5} show evidence for short-range antiferromagnetic ordering at low temperatures. Sm{sub 2}YbCuS{sub 5} shows magnetic ordering at 5.9 K, followed by negative magnetization at low external fields. The band gaps of La{sub 2}YbCuSe{sub 5}, Ce{sub 2}YbCuSe{sub 5}, La{sub 2}YbCuS{sub 5}, Ce{sub 2}YbCuS{sub 5}, Pr{sub 2}YbCuS{sub 5}, Nd{sub 2}YbCuS{sub 5},and Sm{sub 2}YbCuS{sub 5} are 1.15 eV, 1.05 eV, 1.45 eV, 1.37 eV, 1.25 eV, 1.35 eV, and 1.28 eV respectively.

  12. Determination of magnetic anisotropy in the LnTRENSAL complexes (Ln = Tb, Dy, Er) by torque magnetometry.

    Science.gov (United States)

    Perfetti, Mauro; Lucaccini, Eva; Sorace, Lorenzo; Costes, Jean Pierre; Sessoli, Roberta

    2015-04-06

    We report here a study about the magnetic anisotropy of the LnTRENSAL complexes (Ln = Tb, Dy, Er) performed by using cantilever torque magnetometry and electron paramagnetic resonance. For all of the compounds, we extracted a set of crystal-field parameters to obtain the energy-level splitting of the ground-state multiplet.

  13. Unusual N-Alkane Distributions in Extracts from Marine Carbonate Rocks at High Levels of Maturity and Overmaturity

    Institute of Scientific and Technical Information of China (English)

    LI JINGGUI(李景贵); R. PAUL PHILP; CUI MINGZHONG(崔明中)

    2002-01-01

    N-alkanes in extracts from possible carbonate source rocks of the Lower Ordovician Majiagou Formation in the central gas field of the Shanganning Basin and the Upper Sinian Dengying Formation in the Weiyuan gas field of the Sichuan Basin, are characterized by bimodal distributions with the dominant carbon numbers in the range C17-C21 and C25-C29. In most samples, the lower carbon number components are present in greater abundance than the higher carbon number ones. Most samples contain significant concentrations of waxy hydrocarbons ( C22 + )with C21-/C22+ ratios between 0.50 to 3.16, and an average value of 1.34. The n-alkanes in extracts of outcrops and shallow core samples of Upper Proterozoic and Lower Palaeozoic carbonate rocks in the western and southern parts of the North China Basin are of unimodal distributions dominated by n-alkanes maximizing in the C25-C29 range. These extracts have very high concentrations of waxy hydrocarbons with C21 -/C22 + ratios all <1.0, ranging from 0. 14 to 0. 90 and averaging 0.36. AⅡ of the extracts have a marked odd/even predominance in the high molecular weight n-alkane range regardless of whether they are from shallow or deep cores or outcrop samples. Simulation experiments were performed using typical sapropelic-type kerogens from the immature Sinian Lower Xiamalin Formation carbonate-rich shales collected at Jixian,Hebei Province, North China Basin, and the contemporary microplanktonic blue-green algae Spirulina subsala. Results indicate that the unusual distribution of n-alkanes in the extracts of Upper Proterozoic and Lower Palaeozoic carbonate rocks possibly originated from algae in the source rocks at high levels of maturity and overmaturity.

  14. Unusual N—Alkane Distributions in Extracts from Marine Carbonate Rocks at High Levels of Maturity and Overmaturity

    Institute of Scientific and Technical Information of China (English)

    李景贵; R.PAULPHILP; 等

    2002-01-01

    N-alkanes in extracts from possible carbonate source rocks of the Lower Ordovician Majiagou Formation in the central gas field of the Shanganning Basin and the Upper Sinian Dengying Formation in the Weiyuan gas field of the Sichuan Basin,are characterized by bimodal distributions with the dominant carbon numbers in the range C17-C21 and C25-C29.In most sam-ples,the lower carbon number components are present in greater abundance than the higher car-bon number ones.Most samples contain significant concentrations of waxy hydrocarbons(C22+)with C21-/C22+ ratios between 0.50 to 3.16 ,and an average value of 1.34.The n-alkanes in extracts of outcrops and shallow core samples of Upper Proterozoic and Lower Palaeozoic carbon-ate rocks in the western and southern parts of the North China Basin are of unimodal distribu-tions dominated by n-alkanes maximizing in the C25-C29 range.These extracts have very high concentrations of waxy hydrocarbons with C21-/C22+ ratios all<1.0,ranging from 0.14 to 0.90 and averaging 0.36.All of the extracts have a marked odd/even predominance in the high mo-lecular weight n-alkane range regardless of whether they are from shallow or deep cores or out-crop samples.Simulation experiments were performed using typical sapropelic-type kerogens from the immature Sinian Lower Xiamalin Formation carbonate-rich shales collected at Jixian ,Hebei Province,North China Basin ,and the contemporary microplanktonic blue-green algae Spirulina subsala.Results indicate that the unusual distribution of n-alkanes in the extracts of Upper Proterozoic and Lower Palaeozoic carbonate rocks possibly originated from algae in the source rocks at high levels fo maturity and overmaturity.

  15. Unusual treatment of bimaxillary dentoalveolar protrusion via miniscrews and molar extraction.

    Science.gov (United States)

    Al-Fraidi, Ahmad; Afify, Ahmed R

    2012-04-01

    This case report describes the treatment of a Saudi female patient, aged 13 years 8 months at the start of treatment, with a Class I bimaxillary dentoalveolar protrusion and extracted maxillary first molars. Miniscrews were placed bilaterally in the interdental space between both the upper and the lower posterior teeth. The treatment plan consisted of extraction of both lower first permanent molars, distalization of upper and lower premolars using miniscrews followed by en masse retraction of the upper and lower six anterior teeth. The active treatment period was 2 years 8 months. Arch retention was done using upper wrap-around retainer and lower fixed 3-3 retainer. The use of miniscrews helped to resolve the bimaxillary protrusion regardless of extraction pattern used.

  16. Complexation of novel diglycolamide functionalized calix[4]arenes: unusual extraction behaviour, transport, and fluorescence studies

    NARCIS (Netherlands)

    Mohapatra, P.K.; Iqbal, M.; Raut, D.R.; Verboom, Willem; Huskens, Jurriaan

    2012-01-01

    Three diglycolamide functionalized calix[4]arenes (calix[4]-nDGA) were synthesized and evaluated for their extraction behaviour towards lanthanide/actinide ions. Exceptionally high DAm and DPu values indicate these radiotoxic elements can be selectively removed from nuclear waste solutions. Transpor

  17. Unusual Case of Extraction of Maxillary Lateral Incisors and Mandibular Central Incisors

    Directory of Open Access Journals (Sweden)

    Rosa-María Yañez-Vico

    2017-01-01

    Full Text Available Introduction. This article’s purpose is to report a case where maxillary lateral incisors and mandibular central incisors are extracted and a canine substitution was performed as the best therapeutic option in order to obtain symmetry in a malocclusion with an upper lateral incisor with poor prognostic, solve moderate crowding, get enough space for the permanent dentition, and provide stability to the results. Case Report. An 11-year-old boy with straight profile with acute-to-normal nasolabial angle and protruded lips, mixed dentition, lower and upper severe crowding, and a bilateral molar angle Class I. The left maxillary lateral incisor failed endodontic treatment secondary to an intrusive traumatic lesion in the primary and permanent dentition. The treatment of choice was the extraction of both upper lateral incisors and both central lower incisors. The patient finished with molar and canine angle Class I and coincident midlines and was functionally stable; both lateral and protrusive jaw movements were effectively made by the first premolars and central incisors and canines without improper contacts of the rest of the teeth. Overbite of one-third and correct overjet were also achieved, and the esthetic outcome was satisfactory due to the composed material restorations of both the central and lateral incisors, as well as recontouring of the first maxillary premolars.

  18. Unusual seeding mechanism for enhanced performance in solid-phase magnetic extraction of Rare Earth Elements

    Science.gov (United States)

    Polido Legaria, Elizabeth; Rocha, Joao; Tai, Cheuk-Wai; Kessler, Vadim G.; Seisenbaeva, Gulaim A.

    2017-03-01

    Due to the increasing demand of Rare Earth Elements (REE or RE), new and more efficient techniques for their extraction are necessary, suitable for both mining and recycling processes. Current techniques such as solvent extraction or solid adsorbents entail drawbacks such as using big volumes of harmful solvents or limited capacity. Hybrid nanoadsorbents based on SiO2 and highly stable γ-Fe2O3-SiO2 nanoparticles, proved recently to be very attractive for adsorption of REE, yet not being the absolute key to solve the problem. In the present work, we introduce a highly appealing new approach in which the nanoparticles, rather than behaving as adsorbent materials, perform as inducers of crystallization for the REE in the form of hydroxides, allowing their facile and practically total removal from solution. This induced crystallization is achieved by tuning the pH, offering an uptake efficiency more than 20 times higher than previously reported (up to 900 mg RE3+/g vs. 40 mg RE3+/g). The obtained phases were characterized by SEM-EDS, TEM, STEM and EFTEM and 13C and 29Si solid state NMR. Magnetic studies showed that the materials possessed enough magnetic properties to be easily removed by a magnet, opening ways for an efficient and industrially applicable separation technique.

  19. Molecular and supramolecular speciations of solvent extraction systems based on malonamide and/or dialkyl-phosphoric acids for An(III)/Ln(III); Speciations moleculaire et supramoleculaire de systemes d'extraction liquide-liquide a base de malonamide et/ou d'acides dialkylphosphoriques pour la separation An(III)/Ln(III)

    Energy Technology Data Exchange (ETDEWEB)

    Gannaz, B

    2006-06-15

    The solvent extraction system used in the DIAMEX-SANEX process, developed for the actinide(III)/lanthanide(III) separation, is based on the use of mixtures of the malonamide DMDOHEMA and a dialkyl-phosphoric acid (HDEHP or HDHP), in hydrogenated tetra-propylene. The complexity of these systems urges on a novel approach to improve the conventional methods (thermodynamics, solvent extraction) which hardly explain the macroscopic behaviors observed (3. phase, over-stoichiometry). This approach combines studies on both supramolecular (VPO, SANS, SAXS) and molecular (liquid-liquid extraction, ESI-MS, IR, EXAFS) speciations of single extractant systems (DMDOHEMA or HDHP in in n-dodecane) and their mixture. In spite of safety constraints due to the handling of radio-material, they were used in the studies as much as possible, like for SAXS measurements on americium-containing samples, a worldwide first-time. In each of the investigated systems, actinides(III) and lanthanides(III) are extracted to the organic phase in polar cores of reversed micelles, the inner and outer-sphere compositions of which are proposed. Thus, the 4f and 5f cations are extracted by reversed micelles such as [(DMDOHEMA){sub 2}M(NO{sub 3}){sub 3}]{sub inn} (DMDOHEMA){sub x}(HNO{sub 3}){sub z}(H{sub 2}O){sub w}]{sub out} and M(DHP){sub 3}(HDHP){sub y-3}(H{sub 2}O){sub w} with y = 3 to 6, for the single extractant systems. In the case of the two extractants system, the less concentrated one acts like a co-surfactant regarding the mixed aggregate formation [(DMDOHEMA){sub 2}M(NO{sub 3}){sub 3-v}(DHP){sub v}]{sub inn} [(DMDOFIEMA){sub x}(HDHP){sub y}(HNO{sub 3})z(H{sub 2}O){sub w}]{sub out}. (author)

  20. Linking two distinct layered networks of nanosized {Ln18} and {Cu24} wheels through isonicotinate ligands.

    Science.gov (United States)

    Cheng, Jian-Wen; Zhang, Jie; Zheng, Shou-Tian; Yang, Guo-Yu

    2008-01-01

    A new series of heterolanthanide(III)-copper(I) wheel-cluster complexes [Ln6(micro3-O)2](IN)18-[Cu8(micro4-I)2(micro2-I)3].H3O (IN=isonicotinate; Ln=Y 1, Nd 2, Dy 3, Gd 4, Sm 5, Eu 6, Tb 7) were prepared by hydrothermal reaction at low pH. X-ray crystallographic studies reveal that two unusual trinuclear [Ln3(micro3-O)] and tetranuclear [Cu4(micro4-I)] cores are successfully used as secondary building units to make two different nanosized wheels [Ln18(micro3-O)6(CO2)48](6-), {Ln18}, and [Cu24(micro4-I)6(micro2-I)12]6+, {Cu24}, with 12-rings and a diameter of 26.7 and 26.4 A, respectively. The wheels are further assembled into two-dimensional (2D) {Ln18} and {Cu24} networks, the linkages between two distinct layered networks of {Ln18} and {Cu24} wheels by IN pillars along the c axis giving a series of unprecedented three-dimensional (3D) sandwich frameworks. To our knowledge, compounds 1-7 are the first examples containing two different layered networks of nanosized Ln and transition metal (TM) wheels in wheel-cluster chemistry. The IR, UV/Vis, thermogravimetric analysis (TGA), luminescent, and magnetic properties of these complexes were also studied.

  1. Treatment of Class II malocclusion with bialveolar protrusion by means of unusual extractions and anchorage mini-implant

    OpenAIRE

    Jong-Moon Chae

    2012-01-01

    INTRODUCTION: Patients with dental Class II bialveolar protrusion are generally treated by extracting the four first premolars or two first and two second premolars, and retracting the anterior teeth. This case report describes the treatment of an adult patient with bialveolar protrusion, a Class II canine and molar relationship, and lip protrusion. METHODS: In this patient, the maxillary right second molar (1.7) had to be extracted due to extensive caries. To create sufficient space to retra...

  2. An Unusual Complication After the Extraction of a Maxillary Third Molar: Extensive Subcutaneous Emphysema. A Case Report

    Directory of Open Access Journals (Sweden)

    Emrah Soylu

    2016-09-01

    Full Text Available Third molar surgery is one of the most frequently performed procedures in oral and maxillofacial surgery. Various complications including pain, bleeding, infection, edema, hematoma, perforation of the maxillary sinus, and subcutaneous emphysema (SE can occur after third molar surgery. Cervicofacial subcutaneous emphysema (CSE most often occurs after the extraction of third molars, especially when using high-speed air-turbine drills and air syringes, or during dental laser treatment or even after endodontic treatment. This report presents the diagnosis and treatment protocol of a CSE in a 42-year-old healthy male patient that occurred after extraction of a totally erupted upper third molar with just a straight elevator and extraction forceps.

  3. An Unusual Complication After the Extraction of a Maxillary Third Molar: Extensive Subcutaneous Emphysema. A Case Report

    OpenAIRE

    Emrah Soylu

    2016-01-01

    Third molar surgery is one of the most frequently performed procedures in oral and maxillofacial surgery. Various complications including pain, bleeding, infection, edema, hematoma, perforation of the maxillary sinus, and subcutaneous emphysema (SE) can occur after third molar surgery. Cervicofacial subcutaneous emphysema (CSE) most often occurs after the extraction of third molars, especially when using high-speed air-turbine drills and air syringes, or during dental laser treatment or even ...

  4. Treatment of Class II malocclusion with bialveolar protrusion by means of unusual extractions and anchorage mini-implant

    Directory of Open Access Journals (Sweden)

    Jong-Moon Chae

    2012-10-01

    Full Text Available INTRODUCTION: Patients with dental Class II bialveolar protrusion are generally treated by extracting the four first premolars or two first and two second premolars, and retracting the anterior teeth. This case report describes the treatment of an adult patient with bialveolar protrusion, a Class II canine and molar relationship, and lip protrusion. METHODS: In this patient, the maxillary right second molar (1.7 had to be extracted due to extensive caries. To create sufficient space to retract the anterior teeth, the maxillary right posterior teeth were distalized with a maxillary posterior mini-implant (1.2~1.3 mm in diameter, 10 mm long, which was placed into the maxillary tuberosity area and allowed an en masse retraction of the maxillary anterior teeth. RESULTS: Overall, mini-implant can provide anchorage to produce a good facial profile even without additional premolar extraction in cases of dental Class II bialveolar protrusion with the hopeless second molar. CONCLUSION: The total treatment period was 42 months and the results were acceptable for 34 months after debonding.INTRODUÇÃO: os pacientes com Classe II e biprotrusão alveolar são, geralmente, tratados com extração de quatro primeiros pré-molares ou dois primeiros e dois segundos pré-molares, e retração dos dentes anteriores. Este relato de caso descreve o tratamento de um paciente adulto com biprotrusão alveolar, relação de caninos e de molares em Classe II e protrusão labial. MÉTODOS: nesse paciente, o segundo molar superior direito precisou ser extraído devido a cáries extensas. Para criar espaço suficiente para retração dos dentes anteriores, os dentes posterossuperiores direitos foram distalizados com um mini-implante posterossuperior (1,2 ~ 1,3mm de diâmetro, 10mm de comprimento, que foi colocado na área da tuberosidade maxilar e permitiu uma retração em massa dos dentes anteriores. RESULTADOS: em geral, mini-implantes podem fornecer ancoragem para

  5. Computational study of LnGaO3 (Ln = La Gd) perovskites

    Science.gov (United States)

    Senyshyn, A.; Ehrenberg, H.; Vasylechko, L.; Gale, J. D.; Bismayer, U.

    2005-10-01

    Atomistic simulation techniques have been used to study the thermal properties of perovskite-type LnGaO3 (Ln = La-Gd). A set of interatomic potentials describing interatomic interactions in these compounds was developed and tested over a wide temperature range through utilizing free energy minimization. The predicted dielectric constants, thermal expansion coefficients, phonon density of states and its projections, heat capacity and entropy, elastic moduli, Grüneisen parameters, surface energies for main crystallographic directions and Debye temperatures are in good agreement with the limited available experimental data. Perovskite-type LnGaO3 (Ln = La-Gd) compounds have been examined under conditions to which substrate materials are typically subjected. Only a narrow region in the phase diagram of LnGaO3 (Ln = La-Gd) and their solid solutions is recommended for use in substrate applications.

  6. Computational study of LnGaO{sub 3} (Ln = La-Gd) perovskites

    Energy Technology Data Exchange (ETDEWEB)

    Senyshyn, A [Institute for Materials Science, Darmstadt University of Technology, Petersenstrasse 23, D-64287 Darmstadt (Germany); Ehrenberg, H [Institute for Materials Science, Darmstadt University of Technology, Petersenstrasse 23, D-64287 Darmstadt (Germany); Vasylechko, L [Semiconductor Electronics Department, Lviv Polytechnic National University, 12 Bandera Street, 79013 Lviv (Ukraine); Gale, J D [Department of Applied Chemistry, Nanochemistry Research Institute, Curtin University of Technology, PO Box U1987, 6845 Perth, Western (Australia); Bismayer, U [Mineralogisch-Petrographisches Instituet, Universitaet Hamburg, Grindelallee 48, D-20146 Hamburg (Germany)

    2005-10-05

    Atomistic simulation techniques have been used to study the thermal properties of perovskite-type LnGaO{sub 3} (Ln = La-Gd). A set of interatomic potentials describing interatomic interactions in these compounds was developed and tested over a wide temperature range through utilizing free energy minimization. The predicted dielectric constants, thermal expansion coefficients, phonon density of states and its projections, heat capacity and entropy, elastic moduli, Grueneisen parameters, surface energies for main crystallographic directions and Debye temperatures are in good agreement with the limited available experimental data. Perovskite-type LnGaO{sub 3} (Ln = La-Gd) compounds have been examined under conditions to which substrate materials are typically subjected. Only a narrow region in the phase diagram of LnGaO{sub 3} (Ln = La-Gd) and their solid solutions is recommended for use in substrate applications.

  7. Effect of the ion force on the stability constants of the complexes LnCl{sup 2+} and LnCl{sub 2}{sup +} of Europium and Lutetium; Efecto de la fuerza ionica sobre las constantes de estabilidad de los complejos LnCl{sup 2+} y LnCl{sub 2}{sup +} de Europium y Lutetium

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez R, E.; Jimenez R, M.; Solache R, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2004-07-01

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

  8. Preparation of Ln3-xEuxS4 (Ln=Ce,Pr,and Nd) ceramics by pressureless sintering

    Institute of Scientific and Technical Information of China (English)

    YUAN HaiBin; ZHANG JianHui; YU RuiJin; SU Oiang

    2009-01-01

    The preparation of ternary rare earth sulfides of Ln3-xEuxS4(Ln = Ce,Pr,and Nd) ceramics was investigated,and the effect of Eu substitution on Ln3-xEuxS4 ceramics was also studied.Ln3-xEuxS4 powders were synthesized by the sulfurization of their oxide powders using carbon disulfide gas.Ln3-xEuxS4 ceramics were sintered by pressure-less sintering method.All pressureless sintered Ln3-xEuxS4 ceramics crystallized in y-phase.It was found that Eu substitution could improve the density of Ln3-xEuxS4 ceramics.Furthermore,Eu substitution might narrow the optical band gaps of Ln3-xEuxS4 ceramics.

  9. An Unusual Exponential Graph

    Science.gov (United States)

    Syed, M. Qasim; Lovatt, Ian

    2014-01-01

    This paper is an addition to the series of papers on the exponential function begun by Albert Bartlett. In particular, we ask how the graph of the exponential function y = e[superscript -t/t] would appear if y were plotted versus ln t rather than the normal practice of plotting ln y versus t. In answering this question, we find a new way to…

  10. Regionální a strukturální dopady PZI

    OpenAIRE

    Mazánková, Ester

    2007-01-01

    Cílem diplomové práce je zhodnocení regionálních a strukturálních dopadů PZI na Českou republiku. Snahou je zaprvé vysvětlit všeobecná východiska PZI a popsat faktory ovlivňující příliv zahraničního kapitálu do České republiky vůbec a také regionálně. Za druhé zhodnotit příliv zahraničního kapitálu s důrazem na jeho strukturu, a to jak z pohledu teritoriálního, tak z pohledu odvětvového. Na konec je uvedena analýza dopadů PZI v aplikaci na Moravskoslezský region....

  11. Effect of A-TIG Welding Process on the Weld Attributes of Type 304LN and 316LN Stainless Steels

    Science.gov (United States)

    Vasudevan, M.

    2017-03-01

    The specific activated flux has been developed for enhancing the penetration performance of TIG welding process for autogenous welding of type 304LN and 316LN stainless steels through systematic study. Initially single-component fluxes were used to study their effect on depth of penetration and tensile properties. Then multi-component activated flux was developed which was found to produce a significant increase in penetration of 10-12 mm in single-pass TIG welding of type 304LN and 316LN stainless steels. The significant improvement in penetration achieved using the activated flux developed in the present work has been attributed to the constriction of the arc and as well as reversal of Marangoni flow in the molten weld pool. The use of activated flux has been found to overcome the variable weld penetration observed in 316LN stainless steel with welds compared to that of the welds produced by conventional TIG welding on the contrary the transverse strength properties of the 304LN and 316LN stainless steel welds produced by A-TIG welding exceeded the minimum specified strength values of the base metals. Improvement in toughness values were observed in 316LN stainless steel produced by A-TIG welding due to refinement in the weld microstructure in the region close to the weld center. Thus, activated flux developed in the present work has greater potential for use during the TIG welding of structural components made of type 304LN and 316LN stainless steels.

  12. Effect of A-TIG Welding Process on the Weld Attributes of Type 304LN and 316LN Stainless Steels

    Science.gov (United States)

    Vasudevan, M.

    2017-02-01

    The specific activated flux has been developed for enhancing the penetration performance of TIG welding process for autogenous welding of type 304LN and 316LN stainless steels through systematic study. Initially single-component fluxes were used to study their effect on depth of penetration and tensile properties. Then multi-component activated flux was developed which was found to produce a significant increase in penetration of 10-12 mm in single-pass TIG welding of type 304LN and 316LN stainless steels. The significant improvement in penetration achieved using the activated flux developed in the present work has been attributed to the constriction of the arc and as well as reversal of Marangoni flow in the molten weld pool. The use of activated flux has been found to overcome the variable weld penetration observed in 316LN stainless steel with welds compared to that of the welds produced by conventional TIG welding on the contrary the transverse strength properties of the 304LN and 316LN stainless steel welds produced by A-TIG welding exceeded the minimum specified strength values of the base metals. Improvement in toughness values were observed in 316LN stainless steel produced by A-TIG welding due to refinement in the weld microstructure in the region close to the weld center. Thus, activated flux developed in the present work has greater potential for use during the TIG welding of structural components made of type 304LN and 316LN stainless steels.

  13. Synthesis, structure, magnetism, and optical properties of theordered mixed-lanthanide sulfides gamma-LnLn'S3 (Ln=La, Ce; Ln'=Er, Tm,Yb)

    Energy Technology Data Exchange (ETDEWEB)

    Jin, G.B.; Choi, E.S.; Guertin, R.P.; Brooks, J.S.; Bray, T.H.; Booth, C.H.; Albrecht-Schmitt, T.E.

    2006-12-12

    {gamma}-LnLn{prime}S{sub 3} (Ln = La, Ce; Ln{prime} = Er, Tm, Yb) have been prepared as dark red to black single crystals by the reaction of the respective lanthanides with sulfur in a Sb{sub 2}S{sub 3} flux at 1000 C. This isotypic series of compounds adopts a layered structure that consists of the smaller lanthanides (Er, Tm, and Yb) bound by sulfide in six- and seven-coordinate environments that are connected together by the larger lanthanides (La and Ce) in eight- and nine-coordinate environments. The layers can be broken down into three distinct one-dimensional substructures containing three crystallographically unique Ln{prime} centers. The first of these is constructed from one-dimensional chains of edge-sharing [Ln{prime}S{sub 7}] monocapped trigonal prisms that are joined to equivalent chains via edge-sharing to yield ribbons. There are parallel chains of [Ln{prime}S{sub 6}] distorted octahedra that are linked to the first ribbons through corner-sharing. These latter units also share corners with a one-dimensional ribbon composed of parallel chains of [Ln{prime}S{sub 6}] polyhedra that edge-share both in the direction of chain propagation and with adjacent identical chains. Magnetic susceptibility measurements show Curie-Weiss behavior from 2 to 300 K with antiferromagnetic coupling, and no evidence for magnetic ordering. The {theta}{sub p} values range from -0.4 to -37.5 K, and spin-frustration may be indicated for the Yb-containing compounds. All compounds show magnetic moments substantially reduced from those calculated for the free ions. The optical band gaps for {gamma}-LaLn{prime}S{sub 3} (Ln{prime} = Er, Tm, Yb) are approximately 1.6 eV, whereas {gamma}-CeLn{prime}S{sub 3} (Ln{prime} = Er, Tm, Yb) are approximately 1.3 eV.

  14. Electrophilic Ln(III) cations protected by C-F → Ln interactions and their coordination chemistry with weak σ- and π-donors.

    Science.gov (United States)

    Yin, Haolin; Lewis, Andrew J; Carroll, Patrick; Schelter, Eric J

    2013-07-15

    A homoleptic cerium(III) amide complex, Ce(NPh(F)2)3 (1-Ce) (Ph(F) = pentafluorophenyl), in an unusual pseudo-trigonal planar geometry featuring six C-F → Ce interactions was prepared. The C-F → Ln interactions in solution were evident by comparison of the (19)F NMR shifts for the paramagnetic 1-Ce with those of the 4f(0) lanthanum(III) analogue. Coordination of weak σ- and π-donors, including ethers and neutral arene molecules, was achieved by the reversible displacement of the weak C-F → Ce interactions. Computational studies on Ce(NPh(F)2)3 and Ce(NPh(F)2)3(η(6)-C6H3Me3) provide information on the F → Ce interactions and Ce-η(6)-arene bonding.

  15. An anti CuO2-type metal hydride square net structure in Ln2M2As2H(x) (Ln=La or Sm, M=Ti, V, Cr, or Mn).

    Science.gov (United States)

    Mizoguchi, Hiroshi; Park, SangWon; Hiraka, Haruhiro; Ikeda, Kazutaka; Otomo, Toshiya; Hosono, Hideo

    2015-03-02

    Using a high pressure technique and the strong donating nature of H(-), a new series of tetragonal La2Fe2Se2O3-type layered mixed-anion arsenides, Ln2M2As2H(x), was synthesized (Ln=La or Sm, M=Ti, V, Cr, or Mn; x≈3). In these compounds, an unusual M2H square net, which has anti CuO2 square net structures accompanying two As(3-) ions, is sandwiched by (LaH)2 fluorite layers. Notably, strong metal-metal bonding with a distance of 2.80 Å was confirmed in La2Ti2As2H2.3, which has metallic properties. In fact, these compounds are situated near the boundary between salt-like ionic hydrides and transition-metal hydrides with metallic characters.

  16. The formation of the complex manganites LnSr(2)Mn(2)O(7) (Ln = La, Nd, Gd)

    NARCIS (Netherlands)

    Missyul, A. B.; Zvereva, I. A.; Palstra, T. T. M.

    2012-01-01

    The process of formation of the Ruddlesden-Popper phases LnSr(2)Mn(2)O(7) (Ln = La, Nd, Gd) was investigated by means of X-ray diffraction, thermal analysis and microprobe analysis. Two parallel pathways were found for the reaction. The first one includes the formation of the intermediate K2NiF4-typ

  17. A density functional investigation on the electronic and magnetic properties of LnSi (Ln= La-Lu) Diatom

    Indian Academy of Sciences (India)

    Zhao Run-Ning; Chen Rui; Yuan Yan-Hong; Gu Fan; Han Ju-Guang

    2016-03-01

    Bond lengths, vibrational frequencies, electron affinities, magnetic properties, and ionization potentials of the neutral and charged LnSi (Ln=La-Lu) diatom were studied by using the density functional method with relativistic effect being taken into account. Ground state was assigned for each species. The calculated natural populations of LnSi (Ln=La-Lu) exhibit that the charges are transferred mainly from 6s2 to 5d,and most of 4f subshell in LnSi is inert without involving chemical bonding. The calculated highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gaps show that the HOMO-LUMOgaps are increased and exhibit oscillating behavior from LaSi to LuSi.Interestingly, total magnetic properties of LnSi (Ln=La-Lu)diatoms depend on the localized 4f electrons which generate the magnetic moment of LnSi diatoms; additionally, the magnetic moment of EuSi is 11 μB, which is the highest one. Comparisons with the available experimental and theoretical values are made and a good agreement is reached.

  18. Thermoelectric properties of molybdenum oxides LnMo(8)O(14) (Ln = La, Ce, Pr, Nd and Sm)

    DEFF Research Database (Denmark)

    Xu, Jianxiao Jackie; Sonne, Monica; Pryds, Nini

    2010-01-01

    The series LnMo8O14 (Ln = La, Ce, Pr, Nd and Sm) containing bicapped Mo8 clusters was synthesized via solid state reaction at 1673 K. Oxides of this type were reported to be narrow gap semiconductors. Our Seebeck coefficient measurements show that some of these reduced molybdenum oxides exhibit...

  19. The luminescence of doped and undoped BaLn2(MoO4)4 (Ln = La,Gd)

    NARCIS (Netherlands)

    Keller, R.C.A.; Blasse, G.; Lindholm, T.; Leskela, M.

    1988-01-01

    The luminescence of nominally pure BaLn2(MoO4)4 (Ln = La,Gd) is reported. Below 300 K molybdate emission is observed. The following activators were investigated: Eu3+, Tb3+, Pb2+ and Bi3+. The two lanthanide ions show their characteristic emission, the two s2 configuration ions give an emission in w

  20. Molybdate templated assembly of Ln12Mo4-type clusters (Ln = Sm, Eu, Gd) containing a truncated tetrahedron core.

    Science.gov (United States)

    Zheng, Yong; Zhang, Qian-Chong; Long, La-Sheng; Huang, Rong-Bin; Müller, Achim; Schnack, Jürgen; Zheng, Lan-Sun; Zheng, Zhiping

    2013-01-01

    Three heterometallic cluster complexes {Ln(12)Mo(4)} featuring an Ln(12) core of a distorted truncated tetrahedron were synthesized with the assistance of four MoO(4)(2-) anions as ancillary ligands. Magnetic studies of the {Gd(12)Mo(4)} cluster revealed a large magnetocaloric effect due to the presence of the large number of weakly coupled Gd(III) ions.

  1. Magnetic properties of the layered oxypnictides (LnOMnAs (Ln = La, Ce, Pr, Nd

    Directory of Open Access Journals (Sweden)

    Morosawa Y.

    2014-07-01

    Full Text Available We have investigated the rare earth elements dependence on the magnetism to understand the contribution to physical properties of the 4f electrons of (LnOMnAs (Pn = La, Ce, Pr, Nd. (CeOMnAs, (PrOMnAs and (NdOMnAs shows the antiferromagnetic behaviors at low temperature. (CeOMnAs and (NdOMnAs have the magnetic anomalies around 34 K and 24 K, respectively. So, it is speculated that the anomalies depend on the Mn -Mn distance directly

  2. EXTRACT

    DEFF Research Database (Denmark)

    Pafilis, Evangelos; Buttigieg, Pier Luigi; Ferrell, Barbra

    2016-01-01

    The microbial and molecular ecology research communities have made substantial progress on developing standards for annotating samples with environment metadata. However, sample manual annotation is a highly labor intensive process and requires familiarity with the terminologies used. We have the...... and text-mining-assisted curation revealed that EXTRACT speeds up annotation by 15-25% and helps curators to detect terms that would otherwise have been missed.Database URL: https://extract.hcmr.gr/....

  3. A Safe and Brief Way for Preparing Anhydrous LnCl3 (Ln=Sc, Y, La to Lu)

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Anhydrous lanthanide chlorides LnCl3 (Ln=Sc, Y, La to Lu except for Pm), which are difficult to prepare in other ways, were prepared by chemical vapor transport (CVT) process. Rare earth oxide reacted with Al2Cl6 at 300℃ to produce LnCl3, which was then separated from other solids by means of CVT at a temperature gradient from 400 to 180℃. Residual Al2Cl6 (g) was removed by carrier of dry N2 gas at 200℃. The yielding rates were >90%, and the purity of products was >99.5%.

  4. Syntheses and Structures of Alkali Metal Rare Earth Polyphosphates CsLn(PO3)4 (Ln = La, Ce)

    Institute of Scientific and Technical Information of China (English)

    ZHU Jing; CHENG Wen-Dan; ZHANG Hao; WU Dong-Sheng; ZHAO Dan

    2008-01-01

    Alkali metal-rare earth polyphosphates, CsLn(PO3)4 (Ln = La, Ce), were synthesized by the high temperature solution reaction and studied by single-crystal X-ray diffraction technique. They crystallize in the monoclinic space group P21 (Z = 2) and feature infinite PO4 spiral chains linked with neighboring CsO10 and LnO8 polyhedra. In addition, theoretically calculated energy band structure and density of states (DOS) by the density functional theory(DFT) predict that the solid-state compound CsLa(PO3)4 possesses insulative character.

  5. Heat capacity, entropy of Ln2(MoO4)3 (Ln = La, Sm, and Gd), and the high-temperature enthalpy of Ln2(MoO4)3 (Ln = Eu, Dy, and Ho)

    Science.gov (United States)

    Lazarev, V. M.; Suponitskiy, Y. L.; Liashenko, S. E.

    2016-05-01

    The low-temperature heat capacity of Ln2(MoO4)3 (Ln = La, Sm, and Gd) is investigated by means of adiabatic calorimetry within the range of 60-300 K. The temperature dependences of the heat capacity are found and the values of the standard entropy are calculated, based on extrapolations to 0 K. Characteristic temperatures for molybdates are determined from the results of IR spectroscopic studies. The high-temperature enthalpy of Ln2(MoO4)3 (Ln = Eu, Dy, and Ho) is measured via high-temperature microcalorimetry, and the temperature dependence of heat capacity is calculated in the range of 298-1000 K. Since samarium and gadolinium molybdates are of the same structural type as terbium molybdate, we can estimate the anomaly of the heat capacity in the low-temperature region using the data for terbium molybdate and find the entropy of samarium and gadolinium molybdates.

  6. Hydrothermal Synthesis of RbLn2F7 and VUV Spectroscopy of RbLn2F7:Eu3+(Ln=Gd, Y)

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    RbLn2F7 (Ln=Gd, Y, Er, Yb and Lu), crystallized in the hexagonal RbEr2F7 structure type, is synthesized by a hydrothermal method. The excitation spectra of Eu3+-doped RbGd(Y)2F7 suggest that the oxygen content is very low in the samples obtained by hydrothermal synthesis. Only the f-f transitions of Gd3+ ions are observed in the excitation spectrum of RbGd2F7:Eu3+ (0.5mol%), while those of Eu3+ ions do not appear. When the Gd3+ ions are excited, the absorbed energy is transferred efficiently from Gd3+ to Eu3+. The spectra show that the doped Eu3+ ions are located in non-centrosymmetric sites in hexagonal RbLn2F7.

  7. Theoretical aspects of photonic band gap in 1D nano structure of LN: MgLN periodic layer

    Energy Technology Data Exchange (ETDEWEB)

    Sisodia, Namita, E-mail: namitasisodiya@gmail.com [Department of Physics, Holkar Science Collage, Indore-452017 (India)

    2015-06-24

    By using the transfer matrix method, we have analyzed the photonic band gap properties in a periodic layer of LN:MgLN medium. The Width of alternate layers of LN and MgLN is in the range of hundred nanometers. The birefringent and ferroelectric properties of the medium (i.e ordinary, extraordinary refractive indices and electric dipole moment) is given due considerations in the formulation of photonic band gap. Effect of electronic transition dipole moment of the medium on photonic band gap is also taken into account. We find that photonic band gap can be modified by the variation in the ratio of the width of two medium. We explain our findings by obtaining numerical values and the effect on the photonic band gap due to variation in the ratio of alternate medium is shown graphically.

  8. Linear analysis on the stability of lanthanide vapor complexes LnAl3Cli2(Ln = La to Lu)

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The reactions LnCl3 (s) + (3/2)Al2Cl6 (g) = LnAl3Cl12 (g) for Ln = La to Lu were studied by quenching experi-ments in roughly the same temperature and pressure ranges (588-851 K and 0.01-0.22 MPa). Stability constants Kθ oflanthanide complexes LnAl3Cl12 were calculated from the measurements. The values of lg Kθ change linearly with theionpotential (Z+/r) of lanthanide(Ⅲ) from La to Gd and from Tb to Lu, respectively, indicating the Gd break. There exist in-clined W effect between lg Kθ and the total angular momentum L of lanthanide(Ⅲ). And hereby lanthanide elements aredivided into four segments, La-Nd, Pm-Gd, Tb-Ho, and Er-Lu. In each segment, the linearity is maintained.

  9. Decanuclear Ln10 Wheels and Vertex-Shared Spirocyclic Ln5 Cores: Synthesis, Structure, SMM Behavior, and MCE Properties.

    Science.gov (United States)

    Das, Sourav; Dey, Atanu; Kundu, Subrata; Biswas, Sourav; Narayanan, Ramakirushnan Suriya; Titos-Padilla, Silvia; Lorusso, Giulia; Evangelisti, Marco; Colacio, Enrique; Chandrasekhar, Vadapalli

    2015-11-16

    The reaction of a Schiff base ligand (LH3) with lanthanide salts, pivalic acid and triethylamine in 1:1:1:3 and 4:5:8:20 stoichiometric ratios results in the formation of decanuclear Ln10 (Ln = Dy (1), Tb (2), and Gd (3)) and pentanuclear Ln5 complexes (Ln = Gd (4), Tb (5), and Dy (6)), respectively. The formation of Ln10 and Ln5 complexes are fully governed by the stoichiometry of the reagents used. Detailed magnetic studies on these complexes (1-6) have been carried out. Complex 1 shows a SMM behavior with an effective energy barrier for the reversal of the magnetization (Ueff) = 16.12(8) K and relaxation time (τo) = 3.3×10(-5) s under 4000 Oe direct current (dc) field. Complex 6 shows the frequency dependent maxima in the out-of-phase signal under zero dc field, without achieving maxima above 2 K. Complexes 3 and 4 show a large magnetocaloric effect with the following characteristic values: -ΔSm = 26.6 J kg(-1) K(-1) at T = 2.2 K for 3 and -ΔSm = 27.1 J kg(-1) K(-1) at T = 2.4 K for 4, both for an applied field change of 7 T.

  10. Trivalent lanthanide compounds with fluorinated thiolate ligands: Ln-F dative interactions vary with Ln and solvent.

    Science.gov (United States)

    Melman, Jonathan H; Rohde, Christa; Emge, Thomas J; Brennan, John G

    2002-01-14

    The fluorinated tris-thiolate compounds Ln(SC(6)F(5))(3) can be isolated as THF, pyridine, or DME coordination complexes. In THF, the larger Ce forms dimeric [(THF)(3)Ce(SC(6)F(5))(3)](2) (1) with bridging thiolate ligands, while the smaller lanthanides (Ln = Ho (2), Er (3)) form monometallic (THF)(3)Ln(SC(6)F(5))(3) compounds. There is a tendency for fluoride to coordinate to Ln throughout the lanthanide series (Ce-Er). The cerium compound 1 contains a pair of bridging thiolates connecting two eight-coordinate Ce(III) ions. Of the two terminal thiolates, only one exhibits a distinct Ce-F bond. In contrast, the Ho derivative (THF)(3)Ho(SC(6)F(5))(3) is a molecular compound in the solid state, with two monodentate thiolates and one thiolate that again coordinates through both S and F atoms. Incorporation of a stronger Lewis base reduces but does not necessarily eliminate the tendency to form Ln-F bonds. Structural characterization of the eight-coordinate (pyridine)(4)Sm(SC(6)F(5))(3) (4) reveals a single, clearly defined Ln-F interaction, while in (pyridine)(4)Yb(SC(6)F(5))(3) (5) there are no Yb-F bonds. In the structure of (DME)(2)Er(SC(6)F(5))(3) (6) the DME ligands completely displace F from the Er coordination sphere.

  11. Sol-gel preparation and electrical behaviour of Ln: YAG (Ln = Ce, Nd, Ho, Er

    Directory of Open Access Journals (Sweden)

    AIVARAS KAREIVA

    2003-09-01

    Full Text Available A sol-gel method has been developed to prepare pure yttrium aluminum garnet, Y3Al5O12 (YAG, and rare-earth substituted (Ce-Y3Al5O12, Nd-Y3Al5O12, Ho-Y3Al5O12, and Er-Y3Al5O12 samples. The XRD patterns of the polycrystalline powders sintered at 1000ºC showed the formation of monophasic garnet materials. The micro-structural features in the polycristalline samples were studied by scanning electron microscopy. A homogeneous distribution of rare-earth dopants in the YAG lattice was achieved in all of the cases. Electrical conductivity measurements were also performed on the compacts of sol-gel derived Ln-YAG samples. In contrast to the expected dielectric behaviour, the conducting properties of the examined specimens indicate metallic behaviour with the resistivity increasing gradually with increasing temperature.

  12. An Unusual Tachycardia

    OpenAIRE

    Hanon, Sam; Shapiro, Michael; Schweitzer, Paul

    2004-01-01

    The following article presents an unusual case of atrial tachycardia, initially misdiagnosed due to a lack of clear P waves. The diagnosis was eventually confirmed using the atrial electrogram from the patient’s pacemaker.

  13. A phase transfer assisted solvo-thermal strategy for the synthesis of REF₃ and Ln³⁺-doped REF3 nano-/microcrystals.

    Science.gov (United States)

    Zhao, Junmei; Zhu, Menghao; Mu, Linqing; Yang, Zhenzhong; Wang, Li; Gu, Lin; Hu, Yong-Sheng; Dai, Sheng; Liu, Huizhou

    2014-12-15

    Monodisperse orthorhombic-phase rare earth fluorides nano-/microcrystals with a special shape of disk-stacked cylinder have been synthesized via a facile phase transfer assisted solvo-thermal route, where an acid-base-coupled extractant has been employed to transfer hydrofluoric acid into an oil phase as a fluoride source. The synthetic parameters have been optimized and a possible formation mechanism has also been proposed. More importantly, the adopted acid-base-coupled extractant in this route can be recycled. Surveying all of the lanthanides from La to Lu, most of the heavy rare earths, such as Tb, Dy, Ho, Er, Tm and Yb, can form LnF3 nanocrystals with the similar morphologies. Furthermore, Ln(3+)-doped YF3 (Ln=Tb, Yb/Er) nanocrystals have also been synthesized, and their down-conversion and up-conversion (980 nm) luminescent properties were examined. The current approach could be extended to synthesize other metal fluorides nanoparticles.

  14. Serendipitous syntheses of the series Cs 3Ln 7Te 12 (Ln = Sm, Gd, Tb): Compounds with large tunnels

    Science.gov (United States)

    Tougait, Olivier; Noël, Henri; Ibers, James A.

    2001-05-01

    Single crystals of Cs 3Ln 7Te 12 (Ln = Sm, Gd, Tb) have been grown accidentally through the reaction of Ln and Te with a CsCl or Cs 2Te 3 flux at elevated temperatures. The crystal structures have been determined from single crystal X-ray diffraction data. These compounds, which are isostructural with Rb 3Yb 7Se 12, crystallize in space group Pnnm of the orthorhombic system with two molecules in the following cells: Cs 3Sm 7Te 12, a=13.750(6), b=28.332(7), c=4.473(3) Å, T=293 K; Cs 3Gd 7Te 12, a=13.6064(13), b=28.209(3), c=4.4324(4) Å, T=153 K; Cs 3Tb 7Te 12, a=13.5708(16), b=28.116(3), c=4.4147(5) Å, T=153 K.

  15. Magnetic interactions in CuII-LnIII cyclic tetranuclear complexes: is it possible to explain the occurrence of SMM behavior in CuII-TbIII and CuII-DyIII complexes?

    Science.gov (United States)

    Hamamatsu, Takefumi; Yabe, Kazuya; Towatari, Masaaki; Osa, Shutaro; Matsumoto, Naohide; Re, Nazzareno; Pochaba, Andrzej; Mrozinski, Jerzy; Gallani, Jean-Louis; Barla, Alessandro; Imperia, Paolo; Paulsen, Carley; Kappler, Jean-Paul

    2007-05-28

    An extensive series of tetranuclear CuII2LnIII2 complexes [CuIILLnIII(hfac)2]2 (with LnIII being all lanthanide(III) ions except for the radioactive PmIII) has been prepared in order to investigate the nature of the CuII-LnIII magnetic interactions and to try to answer the following question: What makes the CuII2TbIII2 and CuII2DyIII2 complexes single molecule magnets while the other complexes are not? All the complexes within this series possess a similar cyclic tetranuclear structure, in which the CuII and LnIII ions are arrayed alternately via bridges of ligand complex (CuIIL). Regular SQUID magnetometry measurements have been performed on the series. The temperature-dependent magnetic susceptibilities from 2 to 300 K and the field-dependent magnetizations from 0 to 5 T at 2 K have been measured for the CuII2LnIII2 and NiII2LnIII2 complexes, with the NiII2LnIII2 complex containing diamagnetic NiII ions being used as a reference for the evaluation of the CuII-LnIII magnetic interactions. These measurements have revealed that the interactions between CuII and LnIII ions are very weakly antiferromagnetic if Ln=Ce, Nd, Sm, Yb, ferromagnetic if Ln=Gd, Tb, Dy, Ho, Er, Tm, and negligible if Ln=La, Eu, Pr, Lu. With the same goal of better understanding the evolution of the intramolecular magnetic interactions, X-ray magnetic circular dichroism (XMCD) has also been measured on CuII2TbIII2, CuII2DyIII2, and NiII2TbIII2 complexes, either at the L- and M-edges of the metal ions or at the K-edge of the N and O atoms. Last, the CuII2TbIII2 complex exhibiting SMM behavior has received a closer examination of its low temperature magnetic properties down to 0.1 K. These particular measurements have revealed the unusual very slow setting-up of a 3D order below 0.6 K.

  16. Microwave synthesis and photoluminescent properties of Sr2CeO4/Ln3+ (Ln = Er, Ho, Tm)

    Institute of Scientific and Technical Information of China (English)

    KANG Hongge; SONG Huihua; WANG Jiye; Sill Shikao

    2007-01-01

    Sr2CeO4/Ln3+ (Ln = Er, Ho, Tm) phosphors were synthesized with the microwave radiation method for the first time. The luminescent properties of the samples were investi-gated and the up-conversion luminescence of Er3+, Ho3+ and Tm3+ doped Sr2CeO4 phosphors was observed. The spectra indicate that the energy transfer takes place from the triplet excited state ofMLCT (metal-to-ligand charge transfer) state for Sr2CeO4 (sensitizer) to the rare earth ions (activator).

  17. Synthesis, Characterization and Thermal Decomposition of Ln (Me2dtc)3(phen) (Ln=La, Pr, Nd, Sm)

    Institute of Scientific and Technical Information of China (English)

    He Jin; Chen Shanping; Gao Shengli

    2007-01-01

    Four solid complexes of Ln(Me2dtc)3(phen) (Ln=La, Pr, Nd, Sm) were synthesized in anhydrous ethanol by the reaction of lanthanide chloride low hydrate with the mixed ligand of sodium dimethyldithiocarbamate and 1, 10-phenanthroline·H2O (phen·H2O), and characterized by elemental analysis, IR spectroscopy, TG-DTG, and X-ray diffraction analysis. TG-DTG with X-ray powder diffraction showed that these compounds could decompose to lanthanide sulfides at relatively lower temperature, which indicated that the title complexes could be favorable precursors to prepare lanthanide sulfides.

  18. Structural Studies of Layered Cuprates LnLn'CaBa_2Cu_2Ti_3O_14 (LnLn' = NdY, Tb2, TbY, Dy2 and DyY) by Neutron Powder Diffraction

    Science.gov (United States)

    Hu, Z.; Jorgensen, J. D.; Short, S.; Otzschi, K. D.; Poeppelmeier, K. R.; Vander Griend, D.; Kane, M. H.

    1998-03-01

    In this presentation we report the neutron powder diffraction studies on several compounds in a new family of layered cuprates, LnLn'CaBa_2Cu_2Ti_3O_14 (LnLn' = NdY, Tb2, TbY, Dy2 and DyY). All compounds are found to crystallize in space group P 4/mmm. Strong site preferences of B-action (Cu and Ti) are observed in the NdY, Tb2 and TbY systems where Cu atoms strongly prefer 2g (0 0 0.084) sites. Due to the similar neutron scattering length of Nd, Tb, and Y, it is difficult to determine A-cation distributions in the NdY, Tb2 and TbY systems. In the DyY case, however, Dy atoms are found to strongly prefer site the 1 c (0.5 0.5 0) and do not mix with Y atoms on the (0.5 0.5 0.188) sites. The mechanism for these site preferences will be discussed. The oxygen content is found to be slightly different from the theoretical value for all compounds.

  19. Lanthanides extraction processes in molten fluoride media. Application to nuclear spent fuel reprocessing

    OpenAIRE

    Taxil, Pierre; Massot, Laurent; Nourry, Christophe; Gibilaro, Mathieu; Chamelot, Pierre; Cassayre, Laurent

    2009-01-01

    This paper describes four techniques of extraction of lanthanides elements (Ln) from molten salts in the general frame of reprocessing nuclear wastes; One of them is chemical: the precipitation of Ln ions in insoluble compounds (oxides or oxifluorides); the others use electrochemical methodology in molten fluorides for extraction and measurement of the progress of the processes: first electrodeposition of pure Ln metals on an inert cathode material was proved to be incomplete and cause probl...

  20. Influence of lead oxide addition on LnTiTaO6 (Ln = Ce, Pr and Nd) microwave ceramics

    Indian Academy of Sciences (India)

    H Padma Kumar; J K Thomas; Annamma John; Sam Solomon

    2011-02-01

    The effect of PbO addition on the structural, processing and microwave dielectric properties of LnTiTaO6 (Ln = Ce, Pr and Nd) ceramics are reported. Conventional solid state ceramic route was used for the preparation of samples. Phase pure LnTiTaO6 (Ln = Ce, Pr and Nd) ceramics are prepared at a calcination temperature of 1300°C. The samples are sintered at optimized temperatures. Addition of PbO reduces the sintering temperature. The crystal structure of the materials was analysed using X-ray diffraction techniques and the surface morphology of the sintered samples was analysed using scanning electron microscopy. The dielectric constant at microwave frequency range decreases for higher PbO addition for all the samples but the quality factor improves on small PbO addition. The thermal stability of resonant frequency was also improved with PbO addition on all the systems. A number of samples with improved microwave dielectric properties were obtained on all the systems suitable for practical applications.

  1. Crystallographic and spectroscopic characterization of LnFeTeO{sub 6} (Ln = La, Pr, Nd, Sm) materials

    Energy Technology Data Exchange (ETDEWEB)

    Lavat, Araceli E. [Departamento de Ingenieria Quimica, Facultad de Ingenieria, Universidad Nacional del Centro de la Provincia de Buenos Aires, 7400 Olavarria (Argentina); Mercader, Roberto C. [Departamento de Fisica and Instituto IFLP (CONICET), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 1900 La Plata (Argentina); Baran, Enrique J., E-mail: baran@quimica.unlp.edu.a [Centro de Quimica Inorganica (CEQUINOR/CONICET, UNLP), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C. Correo 962, 1900 La Plata (Argentina)

    2010-10-15

    Research highlights: {yields} LnFeTeO{sub 6} (Ln = La, Pr, Nd, Sm) materials belong to a PbSb{sub 2}O{sub 6} superstructure. {yields} IR and Raman spectra are dominated by TeO{sub 6} vibrations. {yields} Te-O bonds are relatively weak.{yields} Fe{sup III}O{sub 6}-polyhedra are scarcely distorted. - Abstract: Four mixed oxides of composition LnFeTeO{sub 6} (with Ln = La, Pr, Nd, Sm), belonging to a superstructure of the PbSb{sub 2}O{sub 6} structural type, have been prepared by solid state reactions and their unit cell parameters determined by X-ray powder diffractometry. The infrared and Raman spectra of these materials were also recorded and briefly discussed, on the basis of a site-symmetry analysis. The {sup 57}Fe-Moessbauer spectra show that the Fe{sup III}O{sub 6} octahedra present in these materials are not greatly distorted.

  2. Microchip Yb:CaLnAlO4 lasers with up to 91% slope efficiency.

    Science.gov (United States)

    Loiko, Pavel; Serres, Josep Maria; Mateos, Xavier; Xu, Xiaodong; Xu, Jun; Jambunathan, Venkatesan; Navratil, Petr; Lucianetti, Antonio; Mocek, Tomas; Zhang, Xuzhao; Griebner, Uwe; Petrov, Valentin; Aguiló, Magdalena; Díaz, Francesc; Major, Arkady

    2017-07-01

    Multi-watt continuous-wave (CW) operation of tetragonal rare-earth calcium aluminate Yb:CaLnAlO4(Ln=Gd,Y)) crystals in plano-plano microchip lasers was demonstrated with an almost quantum-defect-limited slope efficiency. Pumped at 978 nm by an InGaAs laser diode, a 3.4 mm long 8 at. % Yb:CaGdAlO4 laser generated 7.79 W at 1057-1065 nm with a slope efficiency of η=84% (with respect to the absorbed pump power). An even higher η=91% was achieved with a 2.5 mm long 3 at. % Yb:CaYAlO4 laser, from which 5.06 W were extracted at 1048-1056 nm. Both lasers produced linearly polarized output (σ-polarization) with an almost circular diffraction-limited beam (Mx,y2<1.1). The output performance of the developed lasers was modeled, yielding an internal loss coefficient as low as 0.004-0.007  cm(-1). In addition, their spectroscopic properties were revisited.

  3. Crystal growth, structure, and physical properties of Ln(Cu,Al)12 (Ln = Y, Ce, Pr, Sm, and Yb) and Ln(Cu, Ga)12 (Ln = Y, Gd-Er, and Yb).

    Science.gov (United States)

    Drake, Brenton L; Capan, C; Cho, Jung Young; Nambu, Y; Kuga, K; Xiong, Y M; Karki, A B; Nakatsuji, S; Adams, P W; Young, D P; Chan, Julia Y

    2010-02-17

    Single crystals of Ln(Cu,Al)12 and Ln(Cu,Ga)12 compounds (Ln = Y, Ce-Nd, Sm, Gd-Ho, and Yb for Al and Ln = Y, Gd-Er, Yb for Ga) have been grown by flux-growth methods and characterized by means of single-crystal x-ray diffraction, complemented with microprobe analysis, magnetic susceptibility, resistivity and heat capacity measurements. Ln(Cu,Ga)12 and Ln(Cu,Al)12 of the ThMn12 structure type crystallize in the tetragonal I4/mmm space group with lattice parameters a approximately 8.59 Å and c approximately 5.15 Å and a approximately 8.75 Å and c approximately 5.13 Å for Ga and Al containing compounds, respectively. For aluminium containing compounds, magnetic susceptibility data show Curie-Weiss paramagnetism in the Ce and Pr analogues down to 50 K with no magnetic ordering down to 3 K, whereas the Yb analogue shows a temperature-independent Pauli paramagnetism. Sm(Cu,Al)12 orders antiferromagnetically at T(N)approximately 5 K and interestingly exhibits Curie-Weiss behaviour down to 10 K with no Van Vleck contribution to the susceptibility. Specific heat data show that Ce(Cu,Al)12 is a heavy fermion antiferromagnet with T(N) approximately 2 K and with an electronic specific heat coefficient γ0 as large as 390 mJ K2 mol(-1). In addition, this is the first report of Pr(Cu,Al)12 and Sm(Cu,Al)12 showing an enhanced mass (approximately 80 and 120 mJ K(2) mol(-1)). For Ga containing analogues, magnetic susceptibility data also show the expected Curie-Weiss behaviour from Gd to Er, with the Yb analogue being once again a Pauli paramagnet. The antiferromagnetic transition temperatures range over 12.5, 13.5, 6.7, and 3.4 K for Gd, Tb, Dy, and Er. Metallic behaviour is observed down to 3 K for all Ga and Al analogues. A large positive magnetoresistance up to 150% at 9 T is also observed for Dy(Cu,Ga)12. The structure, magnetic, and transport properties of these compounds will be discussed.

  4. Study on optical properties of rare-earth ions in nanocrystalline monoclinic SrAl2O4: Ln (Ln = Ce3+, Pr3+, Tb3+).

    Science.gov (United States)

    Fu, Zuoling; Zhou, Shihong; Zhang, Siyuan

    2005-08-01

    SrAl(2)O(4): Ln (Ln = Ce(3+), Pr(3+), Tb(3+)) nanocrystals have been synthesized by the combustion method. The results of XRD indicated that the resulting SrAl(2)O(4): Ln (Ln = Ce(3+), Pr(3+), Tb(3+)) nanocrystals have a reduced and distorted monoclinic lattice compared with bulk materials. The spectral properties are measured, and it is found that the excitation peaks of 5d energy levels red shift in nanocrystals in contrast to that in bulk crystals. The mechanism of spectra and energy changes is investigated. The order of the degree of red shift for nano SrAl(2)O(4): Ln (Ln = Ce(3+), Pr(3+), Tb(3+)) crystals is Pr(3+) > Ce(3+) > Tb(3+), which is in good agreement with our predicted results.

  5. [Unusual breast scars].

    Science.gov (United States)

    Petit, F; Divaris, M; Guilbert, F

    1999-12-01

    The authors report the case of an unusual form of skin tattoo, discovered on the breasts of a young woman, corresponding to several scars forming a symbolic image, performed deliberately with a burning object. This form of mutilation is called "branding". Imported from England, it is developing in France as a result of fashion, but its followers could one day regret the permanent scars left by this deep burn.

  6. Unusual benign breast lesions

    Energy Technology Data Exchange (ETDEWEB)

    Porter, G.J.R. [Nottingham Breast Institute, City Hospital, Hucknall Rd, Nottingham NG5 1PB (United Kingdom)]. E-mail: gporter@ncht.trent.nhs.uk; Evans, A.J. [Nottingham Breast Institute, City Hospital, Hucknall Rd, Nottingham NG5 1PB (United Kingdom); Lee, A.H.S. [Nottingham Breast Institute, City Hospital, Hucknall Rd, Nottingham NG5 1PB (United Kingdom); Hamilton, L.J. [Nottingham Breast Institute, City Hospital, Hucknall Rd, Nottingham NG5 1PB (United Kingdom); James, J.J. [Nottingham Breast Institute, City Hospital, Hucknall Rd, Nottingham NG5 1PB (United Kingdom)

    2006-07-15

    The purpose of this article is to show examples of the radiological (mammography and/or ultrasound) and pathological appearances of unusual benign breast lesions. The conditions covered are granular cell tumours, fibromatosis, nodular fasciitis, myofibroblastomas, haemangiomas, neurofibromas, and leiomyomas. The article includes the first published description of the ultrasound appearance of a myofibroblastoma. Knowledge of these appearances may help confirm or refute radiological-pathological concordance of percutaneous biopsy results during multidisciplinary assessment of these lesions and aid patient management.

  7. Unusual headache syndromes.

    Science.gov (United States)

    Queiroz, Luiz P

    2013-01-01

    Some headache syndromes have few cases reported in the literature. Their clinical characteristics, pathogenesis, and treatment may have not been completely defined. They may not actually be uncommon but rather under-recognized and/or underreported. A literature review of unusual headache syndromes, searching PubMed and ISI Web of Knowledge, was performed. After deciding which disorders to study, relevant publications in scientific journals, including original articles, reviews, meeting abstracts, and letters or correspondences to the editors were searched. This paper reviewed the clinical characteristics, the pathogenesis, the diagnosis, and the treatment of five interesting and unusual headache syndromes: exploding head syndrome, red ear syndrome, neck-tongue syndrome, nummular headache, and cardiac cephalgia. Recognizing some unusual headaches, either primary or secondary, may be a challenge for many non-headache specialist physicians. It is important to study them because the correct diagnosis may result in specific treatments that may improve the quality of life of these patients, and this can even be life saving. © 2013 American Headache Society.

  8. Photoelectron spectra of the late rare-earth misfit layer compounds (LnS)(1+x)TS2 (Ln=Tb, Dy, Ho; T=Nb, Ta)

    NARCIS (Netherlands)

    Fang, CM; Wiegers, GA; Haas, C

    1997-01-01

    Photoemission spectra (XPS and UPS) are presented for the valence band of misfit layer compounds (LnS)(1+x)TS2 with Ln = Dy, Ho or Tb; T = Nb or Ta. The Nb 4d(x)2 (or Ta 5d(x)2) conduction band is almost filled, which indicates a charge transfer of slightly less than one electron per T from the LnS

  9. Efficient, stable, tunable, and easy to synthesize, handle and recycle luminescent materials: [H2NMe2]3[Ln(III)(2,6-dipicolinolate)3] (Ln = Eu, Tb, or its solid solutions).

    Science.gov (United States)

    Mooibroek, Tiddo Jonathan; Gamez, Patrick; Pevec, Andrej; Kasunic, Marta; Kozlevcar, Bojan; Fu, Wen-Tian; Reedijk, Jan

    2010-07-28

    Three compounds with the general formulae [H(2)N(Me)(2)](3)[Ln(2,6-dpa)(3)] were prepared from cheap and readily available reactants. Microcrystalline compounds could be isolated in high yields (>80%) by a simple filtration, after only one hour reaction time in refluxing DMF. The Eu and Tb compounds have been structurally characterized by single crystal X-ray diffraction. The compounds have unusual high-absorption coefficients (>95%) and quantum efficiencies (approximately 70%). Furthermore, they are thermally stable up to 250 degrees C and appear to be UV and water tolerant. The emission colour of the final compound can be easily fine-tuned, by varying the Eu:Tb ratio during the preparation.

  10. Pyroelectric properties of the monoclinic rare earth nitrates A{sub 2}Ln(NO{sub 3}){sub 5}.4H{sub 2}O (A = NH{sub 4}, Rb; Ln = La, Ce)

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, Matthias; Andersen, Lionel; Becker, Petra; Bohaty Ladislav [Koeln Univ. (Germany). Inst. fuer Kristallographie

    2015-07-01

    The pyroelectric effect of four isomorphic monoclinic (space group Cc), non-ferroelectric rare earth nitrates A{sub 2}Ln(NO{sub 3}){sub 5}.4H{sub 2}O (A = NH{sub 4}, Rb; Ln = La, Ce) was investigated in the temperature range between 100 K and 300 K, using a home-made continuous-flow cryostat for measurements of pyroelectric currents. The symmetry-allowed temperature-dependent change of orientation of the pyroelectric vector p within the mirror plane is unusually large, showing a rotation of p of 148 , 129 , 36 and 40 for (NH{sub 4}){sub 2}La(NO{sub 3}){sub 5}.4H{sub 2}O, (NH{sub 4}){sub 2}Ce(NO{sub 3}){sub 5}.4H{sub 2}O, Rb{sub 2}La(NO{sub 3}){sub 5}.4H{sub 2}O and Rb{sub 2}Ce(NO{sub 3}){sub 5}.4H{sub 2}O, respectively, while changing the temperature from 100 K to 300 K in each case. The pyroelectric coefficients are up to ten times larger than p{sub 3} of tourmaline. In addition, new data of the pyroelectric coefficients of Li{sub 2}SO{sub 4}.H{sub 2}O and BiB{sub 3}O{sub 6} and their temperature dependence are given.

  11. Dynamic Recrystallization and Hot Workability of 316LN Stainless Steel

    Directory of Open Access Journals (Sweden)

    Chaoyang Sun

    2016-07-01

    Full Text Available To identify the optimal deformation parameters for 316LN austenitic stainless steel, it is necessary to study the macroscopic deformation and the microstructural evolution behavior simultaneously in order to ascertain the relationship between the two. Isothermal uniaxial compression tests of 316LN were conducted over the temperature range of 950–1150 °C and for the strain rate range of 0.001–10 s−1 using a Gleeble-1500 thermal-mechanical simulator. The microstructural evolution during deformation processes was investigated by studying the constitutive law and dynamic recrystallization behaviors. Dynamic recrystallization volume fraction was introduced to reveal the power dissipation during the microstructural evolution. Processing maps were developed based on the effects of various temperatures, strain rates, and strains, which suggests that power dissipation efficiency increases gradually with increasing temperature and decreasing stain rate. Optimum regimes for the hot deformation of 316LN stainless steel were revealed on conventional hot processing maps and verified effectively through the examination of the microstructure. In addition, the regimes for defects of the product were also interpreted on the conventional hot processing maps. The developed power dissipation efficiency maps allow optimized processing routes to be selected, thus enabling industry producers to effectively control forming variables to enhance practical production process efficiency.

  12. Structural chemistry and magnetic properties of LnMnFeGe4O12 (Ln = Y, Eu, Lu)

    Science.gov (United States)

    Xu, Diming; Avdeev, Maxim; Battle, Peter D.; Cadogan, J. M.; Lamont, Henry

    2017-10-01

    Polycrystalline samples of LnMnFeGe4O12 (Ln = Y, Eu, Lu) have been prepared using the ceramic method and characterised by a combination of magnetometry, Mössbauer spectroscopy, X-ray diffraction and neutron diffraction. They all adopt the space group P4/nbm with a 9.670, c 4.81 Å and show long-range antiferromagnetic order with transition temperatures 15 ≤ TN/K ≤ 17. The magnetic structure is the same in each case and consists of an A-type ordering of (001) planes; the ordered spins lie in the (001) plane. Comparison with isostructural compounds leads to the conclusion that subtle structural changes play a greater role than the electronic configuration of the cation in determining the magnetic structure.

  13. Observation of upconversion white light and ultrabroad infrared emission in YbAG:Ln3+ (Ln = Nd, Sm, Tb, Er)

    Science.gov (United States)

    Zhu, Yongsheng; Cui, Shaobo; Liu, Mao; Liu, Xuyan; Lu, Cheng; Xu, Xiumei; Xu, Wen

    2015-07-01

    We report on the intense white-light upconversion and ultrabroad infrared (IR) emission for the sol-gel synthesis of Yb3Al5O12 (YbAG):Ln3+ (Ln = Nd, Sm, Tb, Er) following excitation with low-energy near-infrared light (λex = 980 nm). Sufficient cross relaxations and photon avalanches play important roles in the formation of efficient visible and IR broad bands. The brightness of white-light upconversion was 6.2 × 104 cd/m2 at a laser power of 1.47 W, and the IR broad bands (1200-1700 nm) covered all the bands in optical communication media, which indicates that the material might be promising for the development of devices such as white lasers, LEDs, and integrated waveguides.

  14. Quaternary equiatomic compounds LnZnSbO(Ln=La-Nd, Sm) with ZrCuSiAs-type structure

    Energy Technology Data Exchange (ETDEWEB)

    Wollesen, P.; Kaiser, J.W.; Jeitschko, W. [Muenster Univ. (Germany). Anorganisch-Chemisches Inst.

    1997-12-01

    The five compounds LnZnSbO (Ln = La - Nd, Sm) were prepared by annealing cold-pressed pellets of the lanthanoids, zinc oxide, and antimony, or by reacting these components in a NaCl/KCl flux. They crystallize with the tetragonal ZrCuSiAs type structure, which was refined from single-crystal X-ray data of CeZnSbO : P 4/nmm, a = 419.76(4), c = 947.4(1) pm, Z = 2, R = 0.022 for 165 structure factors and 12 variable parameters. Chemical bonding in this and the formally isotypic compound CeZn{sub 1-x}Sb{sub 2} is briefly discussed. (orig.) 36 refs.

  15. Phase Behavior of BaLn2Mn2O7 (Ln=Rare Earth) with a Layered Perovskite Structure

    Institute of Scientific and Technical Information of China (English)

    Naoki Kamegashira; Jian Meng; Takeshi Mikami; Hirohisa Satoh; Noriyoshi Kakuta; Kouji Fujita

    2004-01-01

    Many phases appear in BaLn2Mn2O7 family (Ln=rare earth) belonging to one of the Ruddlesden-Popper type compounds, depending upon the experimental conditions such as heating conditions when prepared and composition. Some of these phases were characterized by powder X-ray diffraction method using Rietveld analysis. These phases have only a little difference in crystal structure which has fundamentally K2NiF4 type structure, although the X-ray diffraction patterns are clearly different: a little deformation or tilting of the oxygen octahedron surrounding a central manganese ion composing the main frame of this structure induce these different diffraction patterns. Phase behavior of these compounds, mainly the detailed relation between various phases in BaTb2Mn2O7, was refined including the data of high temperature X-ray diffractometry.

  16. KCa4(BO33:Ln3+ (Ln = Dy, Eu, Tb phosphors for near UV excited white–light–emitting diodes

    Directory of Open Access Journals (Sweden)

    Allu Amarnath Reddy

    2013-02-01

    Full Text Available A series of doped KCa4(BO33:Ln3+ (Ln: Dy, Eu and Tb compositions were synthesized by solid–state reaction method and their photoluminescent properties were systematically investigated to ascertain their suitability for application in white light emitting diodes. The X–ray diffraction (XRD and nuclear magnetic resonance (MAS–NMR data indicates that Ln3+–ions are successfully occupied the non–centrosymmetric Ca2+ sites, in the orthorhombic crystalline phase of KCa4(BO33 having space group Ama2, without affecting the boron chemical environment. The present phosphor systems could be efficiently excitable at the broad UV wavelength region, from 250 to 350 nm, compatible to the most commonly available UV light–emitting diode (LED chips. Photoluminescence studies revealed optimal near white–light emission for KCa4(BO33 with 5 wt.% Dy3+ doping, while warm white–light (CIE; X = 0.353, Y = 0.369 is obtained at 1wt.% Dy3+ ion concentration. The principle of energy transfer between Eu3+ and Tb3+ also demonstrates the potential white–light from KCa4(BO33:Eu3+,Tb3+ phosphor. Whereas, single Tb3+ and Eu3+–doped systems showed bright green (Tb3+ and red (Eu3+ emissions, respectively. Having structural flexibility along with remarkable chemical/thermal stability and suitable quantum efficiency these phosphors can be promising candidates as white–light–emitter for near UV LEDs.

  17. Strong paramagnetic crystalline LnVO{sub 4} (Ln: Gd, Tb, Dy, Ho, Er) nanoparticles synthesized by a fabricating method

    Energy Technology Data Exchange (ETDEWEB)

    Bulbul, Berna; Beyaz, Seda, E-mail: sedacan@balikesir.edu.tr

    2016-04-15

    Strong paramagnetic lanthanide orthovanadate (LnVO{sub 4}, Ln: Gd, Tb, Dy, Ho, Er) nanoparticles were synthesized under ambient conditions by a novel precipitation method that is economical and fabricating. To the X-ray diffraction patterns, all samples are well-crystallized zircon type orthovanadate and have pure tetragonal phase. Their crystal sizes increased from 12.58 to 15.12 nm with increasing the ionic radii of lanthanide. As confirmed with the surface observation by a transmission electron microscope, it was identified that their two-dimensional projection is an ellipse with the two major axes. It was seen that the sizes of nanoparticles (14.40nm-70.69 nm) were bigger than the crystal sizes because of their polycrystalline structures. Besides, the particle sizes increased with reduction of ionic radii of lanthanide. The magnetic properties obtained from a vibrating sample magnetometer revealed that all nanoparticles are strong paramagnetic at room temperature showing an increase in molar susceptibility up to 4.79 × 10{sup −1} cm{sup 3} mol{sup −1}. Such highly crystalline, small and paramagnetic nanoparticles could be thought to be convenient for biomedical applications. - Highlights: • A general fabricating method for lanthanide orthovanadate nanoparticles is proposed. • The method generates highly small and crystalline nanoparticles. • The reduction in ionic radius of lanthanide (Ln{sup 3+}) causes to increase particle size.

  18. An Unusual Judo Team

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Unusual Li Lingling The deciding match of judo in the 48-kg category at the Eighth National Games was a showdown between the 27-year-old judo legend Li Aiyue from Zhejiang, the world champion, and a 19-year-old from Guangxi Zhuang Autonomous Region named Li Lingling. The fierce competition between the two best judo athletes in China attracted great attention of judo experts and fans. The result? Li Lingling won the championship. Li Lingling grew up in Guilin, a region famous for its beautiful landscape. Although she only began training in judo

  19. Glass Ceramic Waste Forms for Combined CS+LN+TM Fission Products Waste Streams

    Energy Technology Data Exchange (ETDEWEB)

    Crum, Jarrod V.; Turo, Laura A.; Riley, Brian J.; Tang, Ming; Kossoy, Anna; Sickafus, Kurt E.

    2010-09-23

    In this study, glass ceramics were explored as an alternative waste form for glass, the current baseline, to be used for immobilizing alkaline/alkaline earth + lanthanide (CS+LN) or CS+LN+transition metal (TM) fission-product waste streams generated by a uranium extraction (UREX+) aqueous separations type process. Results from past work on a glass waste form for the combined CS+LN waste streams showed that as waste loading increased, large fractions of crystalline phases precipitated upon slow cooling.[1] The crystalline phases had no noticeable impact on the waste form performance by the 7-day product consistency test (PCT). These results point towards the development of a glass ceramic waste form for treating CS+LN or CS+LN+TM combined waste streams. Three main benefits for exploring glass ceramics are: (1) Glass ceramics offer increased solubility of troublesome components in crystalline phases as compared to glass, leading to increased waste loading; (2) The crystalline network formed in the glass ceramic results in higher heat tolerance than glass; and (3) These glass ceramics are designed to be processed by the same melter technology as the current baseline glass waste form. It will only require adding controlled canister cooling for crystallization into a glass ceramic waste form. Highly annealed waste form (essentially crack free) with up to 50X lower surface area than a typical High-Level Waste (HLW) glass canister. Lower surface area translates directly into increased durability. This was the first full year of exploring glass ceramics for the Option 1 and 2 combined waste stream options. This work has shown that dramatic increases in waste loading are achievable by designing a glass ceramic waste form as an alternative to glass. Table S1 shows the upper limits for heat, waste loading (based on solubility), and the decay time needed before treatment can occur for glass and glass ceramic waste forms. The improvements are significant for both combined waste

  20. Solvent Extraction of Some Lanthanides with Trioctylphosphine Oxide in Molten Paraffin Wax

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The extraction behavior of Ln(Ⅲ) (Ln=Nd, Sm, Tb and Yb) with trioctylphosphine oxide (TOPO) in molten paraffin wax has been studied. The effect of pH, TOPO concentration, medium, stirring time and the amount of salts added on the distribution of lanthanides between two phases were investigated. Two different compositions Ln(H2O)s€?(TOPO)2(OH)2NO3 (Ln=Nd and Sm) and Ln(H2O)s€?(TOPO)2(OH)(NO3)2 (Ln=Tb and Yb) were determined by slope analysis method. The equilibrium extraction constant Kex and pH1/2 value were calculated and the thermodynamic parameters were obtained from the dependence of Kex on the temperature.

  1. Characterization and properties of new dielectric ceramics Ba5LnZnNb9O30(Ln=La,Nd and Sm)

    Institute of Scientific and Technical Information of China (English)

    ZHU Wen-feng; HU Chang-zheng; WU Bo-lin; FANG Liang

    2006-01-01

    Three novel dielectric ceramics Ba5LnZnNb9O30 (Ln= La,Nd and Sm) were synthesized and characterized in the BaO-Ln2O3-ZnO-Nb2O5 quaternary system,which formed the filled tungsten-bronze structures. The present ceramics exhibit high dielectric constant (εr) up to 310,low dielectric loss in the level of 10-3 at 1 MHz . Meanwhile,the temperature coefficients of the dielectric constant (τε) of Ba5LnZnNb9O30 varies from -1 390×10-6 to -1 220×10-6/℃ as the radius of Ln3+ increases. The present ceramics are promising candidates for high dielectric constant and low loss dielectric ceramics.

  2. Exploring the effect of the Ln(III)/Ln(II) redox potential on C-F activation and on oxidation of some lanthanoid organoamides.

    Science.gov (United States)

    Deacon, Glen B; Junk, Peter C; Kelly, Rory P; Wang, Jun

    2016-01-28

    The divalent europium complexes, and (L(Me/Et) = p-HC6F4N(CH2)2NMe2/Et2), have been prepared from redox-transmetallation/protolysis (RTP) reactions between Eu metal, Hg(C6F5)2 and L(Me/Et)H in thf. The complexes exhibit close (C)F-Ln interactions and the amide ligands feature tridentate N,N',F chelation. The complexes are thermally robust but on exposure to light they undergo C-F activation. From exposure of to light, the Eu(III) mixed fluoride/oxide cluster, was isolated, but other well-defined C-F activation products have proven elusive due to the stability of Eu(II). Oxidation of [Ln(L(R))2(thf)2] (Ln = Eu, R = Me; Ln = Yb, R = Et) with I2 afforded the heteroleptic iodo complexes, [Ln(L(R))2I(thf)n] (Ln = Eu, n = 1; Ln = Yb, n = 0), and the homoleptic complexes, [Ln(L(R))3]. The formation of the iodo complexes and the heteroleptic complexes appear to occur by different routes. shows interesting structural differences from reported [Ln(L(Et))3] (Ln = La, Ce, Nd) complexes, and highlights an incomplete shift towards N,N' chelation to the much smaller Yb ion. was prepared from a protolysis reaction between [Sm(CH2C6H4-NMe2-o)3] and L(Me)H. Heating a solution of in toluene at 110 °C for three days did not afford any samarium fluoride complex. An RTP reaction with Sm afforded the heteroleptic samarium complex, , in very low yield. From an attempted protolysis reaction between [Sm(DippForm)2(thf)2] and L(Me)H, the mixed ligand samarium fluoride complex, , was isolated. Overall, the instability of Sm(II) precludes control over the C-F activation reactions.

  3. Unusual case of tuberculosis

    Directory of Open Access Journals (Sweden)

    Vatsal Bachkaniwala

    2015-12-01

    Full Text Available Though commonly encountered, extrapulmonary tuberculosis (TB can sometimes present with variable clinical picture intricating the diagnosis. The nonspecific symptoms include pyrexia of unknown origin, hepatosplenomegaly, lymphadenopathy, meningitis, and, rarely, variety of hematological abnormalities, namely, anemia, pancytopenia, and leukemoid reaction. When it presents with bone marrow (BM involvement, prognosis is usually poor. We, hereby, report a case of unusual TB presentation with a 4 month history of fever associated with fatigability, and diarrhea. During the hospital stay and follow up, the patient showed a spectrum of interesting hematological findings, including pancytopenia on peripheral smear, caseating granulomas consistent with TB on bone marrow examination. The patient showed a good clinical as well as hematological response to anti-tuberculosis treatment. This paper highlights the significance of a hematological picture in the final confirmation of TB, which may otherwise be passed off as nutritional or other unrelated causes. [Int J Res Med Sci 2015; 3(12.000: 3921-3923

  4. [Unusual Migraine Manifestations].

    Science.gov (United States)

    Schipper, Sivan; Gantenbein, Andreas R; Sandor, Peter S

    2016-06-01

    Migraine is a complex neurologic disorder by which several systems of the central nervous system (autonomous system, affective, cognitive, sensoric and motoric system) may be affected on different levels. Around a fourth of the patients have migraine aura. The most common aura is the visual aura, followed by sensoric aura. But motoric deficits as well as deficits of higher cortical centers (disorders of thinking, orientation, coherence or concentration) may occur as well. In analogy with a headache calendar, an aura calendar can deliver important help in the diagnostic process of rare migraine manifestations and prevent underdiagnosis of unusual migraine manifestations. Complex migraine manifestations are diagnoses of exlusion, and a broad diagnostic work-up is warranted in order to exclude dangerous neurologic pathologies. There are no specific therapeutic recommendations, as there is a lack of randomized controlled studies.

  5. Unusual ISS Rate Signature

    Science.gov (United States)

    Laible, Michael R.

    2011-01-01

    On November 23, 2011 International Space Station Guidance, Navigation, and Control reported unusual pitch rate disturbance. These disturbances were an order of magnitude greater than nominal rates. The Loads and Dynamics team was asked to review and analyze current accelerometer data to investigate this disturbance. This paper will cover the investigation process under taken by the Loads and Dynamics group. It will detail the accelerometers used and analysis performed. The analysis included performing Frequency Fourier Transform of the data to identify the mode of interest. This frequency data is then reviewed with modal analysis of the ISS system model. Once this analysis is complete and the disturbance quantified, a forcing function was produced to replicate the disturbance. This allows the Loads and Dynamics team to report the load limit values for the 100's of interfaces on the ISS.

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

    Science.gov (United States)

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

    2013-06-03

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

  7. Synthesis and Characterization of Ethylthioethylcyclopentadienyl Organolanthanide Complexes:Cp2Th LnCl (Ln=Gd, Dy), Cp2LnCpTh (Ln=Yb, Sm, Dy, Y) and Cp2ThErCl2·2THF

    Institute of Scientific and Technical Information of China (English)

    ZHU Ming朱铭; ZHANG Li-Bei张丽蓓; CHEN Ying-Hua陈应华; ZHOU Xi-Geng周锡庚; CAI Rui-Fang蔡瑞芳; WENG Lin-Hong翁林红

    2004-01-01

    Six new ethylthioethylcyclopentadienyl-containing organolanthanide complexes Cp2Th LnCl [Ln=Gd (1), Dy (2)]and Cp2LnCpTh [Cp=C5H5, Ln=Yb (3), Sm (4), Dy (5), Y (6)] were synthesized by the reaction of ethylthioethylcyclopentadienyl (CpTh) sodium salt with LnC13 or Cp2LnCl in THF. Complexes 1-6 were characterized by elemental analyses, infrared and mass spectroscopies. The molecular structures of complexes 1-3 were also determined by the X-ray single crystal diffraction. The results show that the side-chain sulfur atom on the ethylthioethylcyclopentadienyl ring can form intramolecular chelating coordination to the central lanthanide ion, improving the stability of organolanthanide complexes and reducing the number of coordinated THF molecules.

  8. Synthesis, structure, magnetic and transport properties of LnFeSb3 (Ln = Pr, Nd, Sm, Gd, and Tb)--tuning of anisotropic long-range magnetic order as a function of Ln.

    Science.gov (United States)

    Phelan, W Adam; Nguyen, Giang V; Karki, Amar B; Young, David P; Chan, Julia Y

    2010-07-28

    Single crystals of LnFeSb(3) (Ln = Pr, Nd, Sm, Gd, and Tb) have been grown from excess Sb flux. The crystal structure consists of (infinity)(2)[FeSb(2)] octahedra separated by layers of Ln atoms and nearly square planar nets of (infinity)(2)[Sb(2)]. These compounds are metallic and display anisotropic magnetic properties. Long-range antiferromagnetic order is observed in the Sm, Gd, and Tb samples when the magnetic field is applied along the crystallographic a-axis. Evidence of magnetic ordering in all the samples is observed for the field applied parallel to the layers. The magnetic properties are well-described by considering only the magnetic interactions between the Ln 4f moments, with no contribution from the Fe sublattice. Herein, we report the crystal growth, structure, magnetization, transport, and chemical stabilities of the title compounds.

  9. Convergence Rate of the L-N Estimator in Poisson-Gamma Models

    Institute of Scientific and Technical Information of China (English)

    Na Xia; Zhong-zhan Zhang; Zhi-liang Ying

    2006-01-01

    We focus on in this paper the convergence rate of the L-N estimators for the fixed effect β in Poisson-Gamma models which are typical hierarchical generalised linear models(HGLMs). Under the proper assumptions on response variables and some smoothing conditions, we obtain the strong consistency and the convergence rate of the L-N estimator based on the combination of L-N and quasi-likelihood.

  10. Probing the magnetic and magnetothermal properties of M(II)-Ln(III) complexes (where M(II) = Ni or Zn; Ln(III) = La or Pr or Gd).

    Science.gov (United States)

    Ahmed, Naushad; Das, Chinmoy; Vaidya, Shefali; Srivastava, Anant Kumar; Langley, Stuart K; Murray, Keith S; Shanmugam, Maheswaran

    2014-12-14

    We establish the coordination potential of the Schiff base ligand (2-methoxy-6-[(E)-2'-hydroxymethyl-phenyliminomethyl]-phenolate (H2L)) via the isolation of various M(II)-Ln(III) complexes (where M(II) = Ni or Zn and Ln(III) = La or Pr or Gd). Single crystals of these five complexes were isolated and their solid state structures were determined by single crystal X-ray diffraction. Structural determination revealed molecular formulae of [NiGd(HL)2(NO3)3] (1), [NiPr(HL)2(NO3)3] (2) and [Ni2La(HL)4(NO3)](NO3)2 (3), [Zn2Gd(HL)4(NO3)](NO3)2 (4), and [Zn2Pr(HL)4(NO3)](NO3)2 (5). Complexes and were found to be neutral heterometallic dinuclear compounds, whereas 3-5 were found to be linear heterometallic trinuclear cationic complexes. Direct current (dc) magnetic susceptibility and magnetization measurements conclusively revealed that complexes 1 and 4 possess a spin ground state of S = 9/2 and 7/2 respectively. Empirically calculated ΔχMT derived from the variable temperature susceptibility data for all complexes undoubtedly indicates that the Ni(II) ion is coupled ferromagnetically with the Gd(III) ion, and antiferromagnetically with the Pr(III) ion in 1 and 2 respectively. The extent of the exchange interaction for was estimated by fitting the magnetic susceptibility data using the parameters (g = 2.028, S = 9/2, J = 1.31 cm(-1) and zJ = +0.007), supporting the phenomenon observed in an empirical approach. Similarly using a HDVV Hamiltonian, the magnetic data of 3 and 4 were fitted, yielding parameters g = 2.177, D = 3.133 cm(-1), J = -0.978 cm(-1), (for 3) and g = 1.985, D = 0.508 cm(-1) (for 4). The maximum change in magnetic entropy (-ΔSm) estimated from the isothermal magnetization data for was found to be 5.7 J kg(-1) K(-1) (ΔB = 7 Tesla) at 7.0 K, which is larger than the -ΔSm value extracted from 4 of 3.5 J kg(-1) K(-1) (ΔB = 7 Tesla) at 15.8 K, revealing the importance of the exchange interaction in increasing the overall ground state of a molecule for

  11. Ab initio prediction of the electronic, magnetic and topological properties of Ln2O3 clusters

    Science.gov (United States)

    Xia, Xiuli; Shao, Yuanzhi

    2017-07-01

    The structural, electronic and magnetic properties of the lanthanide oxide Ln2O3 clusters, where Ln signifies lanthanides from La to Lu, have been calculated using spin-polarized density functional theory with the B3LYP hybrid functional. The intensities of ferromagnetic RKKY interaction are found comparable with that of antiferromagnetic superexchange interaction in Ce2O3 / Pr2O3 / Nd2O3 / Gd2O3 / Tb2O3 / Tm2O3 clusters, while the other Ln2O3 clusters prefer ferromagnetic states to antiferromagnetic states in energy, except nonmagnetic La2O3 and Lu2O3 clusters. The theoretical spin magnetic moments, calculated three-dimensional spin density maps and dipole moments of Ln2O3 clusters suggest that the induced polarizations of oxygen atoms in Sm2O3, Eu2O3 and Yb2O3 clusters remarkably lead to the elongated Ln-O bond lengths in these clusters. The partial density of states of Ln2O3 clusters reveals that Sm3+ /Eu3+ /Yb3+ ions are distinctive from other Ln3+ ions in that their Ln-4f electrons are strongly hybrid with O-2 p electrons. The topological analysis of the electron density was also performed with quantum theory of atoms in molecules, which indicates the ionic Ln-O bonds have partial covalent characteristics.

  12. Single-molecule magnet behavior and magnetocaloric effect in ferromagnetically coupled Ln(III)-Ni(II)-Ni(II)-Ln(III) (Ln(III) = Dy(III) and Gd(III)) linear complexes.

    Science.gov (United States)

    Meseguer, Carlos; Titos-Padilla, Silvia; Hänninen, Mikko M; Navarrete, R; Mota, A J; Evangelisti, Marco; Ruiz, José; Colacio, Enrique

    2014-11-17

    New types of linear tetranuclear Ln(III)-Ni(II)-Ni(II)-Ln(III) (Ln(III) = Dy (1), Gd (2)) complexes have been prepared using the multidentate ligand N,N'-bis(3-methoxysalicylidene)-1,3-diaminobenzene, which has two sets of NO and OO' coordination pockets that are able to selectively accommodate Ni(II) and Ln(III) ions, respectively. The X-ray structure analysis reveals that the Ni(II) ions are bridged by phenylenediimine groups forming a 12-membered metallacycle in the central body of the complex, whereas the Ln(III) ions are located at both sides of the metallacycle and linked to the Ni(II) ions by diphenoxo bridging groups. Phenylenediimine and diphenoxo bridging groups transmit ferromagnetic exchange interactions between the two Ni(II) ions and between the Ni(II) and the Ln(III) ions, respectively. Complex 1 shows slow relaxation of the magnetization at zero field and a thermal energy barrier Ueff = 7.4 K with HDC = 1000 Oe, whereas complex 2 exhibits an S = 9 ground state and significant magnetocaloric effect (-ΔSm = 18.5 J kg(-1) K(-1) at T = 3 K and ΔB = 5 T).

  13. Structures, magnetic and dielectric properties of the ordered double perovskites LnPbNiSbO6 (Ln = La, Pr)

    Science.gov (United States)

    Han, Lin; Bai, Yijia; Liu, Xiaojuan; Yao, Chuangang; Meng, Junling; Liang, Qingshuang; Wu, Xiaojie; Meng, Jian

    2014-09-01

    The crystal structures, magnetic and dielectric properties for the ordered double perovskites LnPbNiSbO6 (Ln = La, Pr) have been investigated. Rietveld refinements of x-ray diffraction data have been indexed for the monoclinic symmetry in space group P21/n (No. 14) and a highly rock-salt ordered arrangement of NiO6 and SbO6 octahedra. The B-site lattices are distorted strongly due to the substitution of rare Earth ions at the A-site. The magnetization measurements show an antiferromagnetic ordering. The effective magnetic moments μ eff are larger than the spin-only values, suggesting that the orbital component for Ni2+ is significant. The maximum values of isothermal magnetization increase due to the lattice distortion of BO6 octahedra, which may weaken the antiferromagnetic interaction via Ni2+-O-Sb5+-O-Ni2+ paths. The dielectric constants for LaPbNiSbO6 present frequency dependence and the tan δ curves exhibit relaxor-like dielectric response. The ɛ‧ decreases with the reduction of the magnetic moments of B-site transition metal ions, which reveals a relationship between the dielectric and magnetic properties.

  14. Solid-state synthesis of monazite-type compounds LnPO{sub 4} (Ln = La to Gd)

    Energy Technology Data Exchange (ETDEWEB)

    Bregiroux, D.; Audubert, F. [CEA Cadarache (DEN/DEC/SPUA/LTEC), 13 - Saint-Paul-lez-Durance (France). Dept. d' Etudes des Combustibles; Bregiroux, D. [Laboratoire Science des Procedes Ceramiques et de Traitements de Surface, UMR CNRS-Universite 6638, 87 - Limoges (France); Charpentier, Th.; Sakellariou, D. [CEA Saclay (DSM/DRECAM/SCM/LSDRM), CEA-CNRS URA 331, 91 - Gif-sur-Yvette (France). Direction des Sciences de la Matiere; Bernache-Assollant, D. [Ecole Nationale Superieure des Mines, CIS, 42 - Saint Etienne (France)

    2007-07-01

    This work is devoted to the synthesis of monazite-type compounds LnPO{sub 4} (with Ln = La, Ce, Pr, Nd, Sm, Eu and Gd) by solid-solid reaction between a lanthanide oxide and a phosphate precursor NH{sub 4}H{sub 2}PO{sub 4}. Starting mixtures and resulting powders were characterized by coupling different techniques, in particular thermal analysis, X-ray diffraction and MAS {sup 31}P NMR. Results are presented according to the valence state of the lanthanide element in its oxide form. The intermediate chemical reactions occurring during the firing of starting reagents are described for the first time in the case of monazite with one or several cations. It has been highlighted that the solid-state route is an efficient way in order to obtain very pure and very well crystallized monazite powder. Optimum synthesis conditions are 1350 C-2h. The synthesis of monazite powders containing several lanthanides appears to be more difficult, because all the lanthanides do not react at the same temperature, leading to the formation of heterogeneous powders. (authors)

  15. Thermodynamic studies on LnCoO{sub 3}(s) (Ln = Dy, Ho) by solid-state electrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Abhay [Product Development Section, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Dash, Smruti [Product Development Section, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)], E-mail: smruti@barc.gov.in; Parida, S.C.; Venugopal, V. [Product Development Section, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2009-01-05

    Ternary oxides, DyCoO{sub 3}(s) and HoCoO{sub 3}(s) have been synthesized by citrate-nitrate gel combustion method and characterized by X-ray powder diffraction method. The standard molar Gibbs energies of formation of DyCoO{sub 3}(s) and HoCoO{sub 3}(s) have been measured using solid oxide galvanic cell technique employing yttria-stabilized zirconia (YSZ) and calcia-stabilized zirconia (CSZ) as solid electrolyte tubes, respectively. The standard molar Gibbs energies of formation of DyCoO{sub 3}(s) and HoCoO{sub 3}(s) were calculated from the measured e.m.f. data and are given as: {delta}{sub f}G{sub m}{sup o}(DyCoO{sub 3},s,T)kJmol{sup -1}({+-}4)=-1211.3+0.2449{sup *}(TK),(1013K{<=}T{>=}1167K), {delta}{sub f}G{sub m}{sup o}(HCoO{sub 3},s,T)kJmol{sup -1}({+-}4)=-1237.8+0.2590{sup *}(TK).(964K{<=}T{>=}1102K), A set of self consistent thermodynamic functions for LnCoO{sub 3}(s) (Ln = La, Nd, Sm, Eu, Gd, Dy, Ho) has been computed from available experimental data in the literature.

  16. 4X6" Rotary Bayonet LN2 Test Fill

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, J.B.; /Fermilab

    1988-08-02

    This engineering note describes a test fill of the 4-inch x 6-inch rotary bayonet test fixture with LN{sub 2}. This test verifies the operation of valves on the fixture, and checks for proper construction/insulation. Further cold testing is imminent (with rotation and moment loading of the bayonet) after proper construction is verified and the test fixture is accepted. While this test fixture is a pressure vessel (4-inch), it does not require special safety treatment because it is under 6-inch in diameter. Flow capacity calculations were done to insure that the relief valve chosen would be capable of handling fire/loss of vacuum conditions. The D-Zero Safety Committee Chairman was notified of this testing.

  17. Ultralarge 3d/4f Coordination Wheels: From Carboxylate/Amino Alcohol-Supported {Fe4Ln2} to {Fe18Ln6} Rings

    Science.gov (United States)

    2017-01-01

    A family of wheel-shaped charge-neutral heterometallic {FeIII4LnIII2}- and {FeIII18MIII6}-type coordination clusters demonstrates the intricate interplay of solvent effects and structure-directing roles of semiflexible bridging ligands. The {Fe4Ln2}-type compounds [Fe4Ln2(O2CCMe3)6(N3)4(Htea)4]·2(EtOH), Ln = Dy (1a), Er (1b), Ho (1c); [Fe4Tb2(O2CCMe3)6(N3)4(Htea)4] (1d); [Fe4Ln2(O2CCMe3)6(N3)4(Htea)4]·2(CH2Cl2), Ln = Dy (2a), Er (2b); [Fe4Ln2(O2CCMe3)4(N3)6(Htea)4]·2(EtOH)·2(CH2Cl2), Ln = Dy (3a), Er (3b) and the {Fe18M6}-type compounds [Fe18M6(O2CCHMe2)12(Htea)18(tea)6(N3)6]·n(solvent), M = Dy (4, 4a), Gd (5), Tb (6), Ho (7), Sm (8), Eu (9), and Y (10) form in ca. 20–40% yields in direct reaction of trinuclear FeIII pivalate or isobutyrate clusters, lanthanide/yttrium nitrates, and bridging triethanolamine (H3tea) and azide ligands in different solvents: EtOH for the smaller {Fe4Ln2} wheels and MeOH/MeCN or MeOH/EtOH for the larger {Fe18M6} wheels. Single-crystal X-ray diffraction analyses revealed that 1–3 consist of planar centrosymmetric hexanuclear clusters built from FeIII and LnIII ions linked by an array of bridging carboxylate, azide, and aminopolyalcoholato-based ligands into a cyclic structure with a cavity, and with distinct sets of crystal solvents (2 EtOH per formula unit in 1a–c, 2 CH2Cl2 in 2, and 2 EtOH and 2 CH2Cl2 in 3). In 4–10, the largest 3d/4f wheels currently known, nearly linear Fe3 fragments are joined via mononuclear Ln/Y units by a set of isobutyrates and amino alcohol ligands into virtually planar rings. The magnetic properties of 1–10 reveal slow magnetization relaxation for {Fe4Tb2} (1d) and slow relaxation for {Fe4Ho2} (1c), {Fe18Dy6} (4), and {Fe18Tb6} (6). PMID:28135085

  18. Effect of inclining strain on the crystal lattice along an extended series of lanthanide hydroxysulfates Ln(OH)SO4 (Ln = Pr-Yb, except Pm).

    Science.gov (United States)

    Zehnder, Ralph A; Wilson, Christopher S; Christy, Hunter T; Harris, Kenneth S; Chauhan, Varun; Schutz, Victor; Sullivan, Matthew; Zeller, Matthias; Fronczek, Frank R; Myers, Jacob A; Dammann, Kyle; Duck, James; Smith, Peter M; Okuma, Antony; Johnson, Kristin; Sovesky, Robert; Stroudt, Cameron; Renn, Robert A

    2011-02-07

    A series of trivalent lanthanide hydroxysulfates, Ln(OH)SO(4), (Ln = Pr through Yb, except radioactive Pm) has been synthesized via hydrothermal methods from Ln(2)(SO(4))(3)·8H(2)O by reaction with aqueous NaOH at 170 °C in Teflon lined Parr steel autoclaves, and were characterized by single crystal X-ray diffraction and FT-IR spectroscopy. Two types of arrangements were found in the solid state. The lighter (Ln = Pr-Nd, Sm-Gd) and heavier lanthanide(III) hydroxysulfates (Tb-Yb) are each isostructural. Both structure types exhibit the monoclinic space group P2(1)/n, but the unit cell content is doubled with two crystallographically distinct LnO(8) polyhedra for the heavier lanthanide compounds. The lighter complexes maintain the coordination number 9, forming a three-dimensional extended lattice. The heavier counterparts exhibit the coordination number 8, and arrange as infinite columns of two crystallographically different LnO(8) polyhedra, while extending along the "c" axis. These columns of LnO(8) polyhedra are surrounded and separated by six columns of sulfate ions, also elongating in the "c" direction. The rigid sulfate entities seem to obstruct the closing in of the lighter LnO(9) polyhedra, and show an inclining degree of torsion into the "ac" layers. The crystal lattice of the lighter 4f complexes can sufficiently withstand the tension buildup, caused by the decreasing Ln(3+) radius, up to Gd(OH)SO(4). The energy profile of this structural arrangement then seems to exceed levels at which this structure type is favorable. The lattice arrangement of the heavier Ln-analogues seems to offer a lower energy profile. This appears to be the preferred arrangement for the heavier lanthanide hydroxysulfates, whose crystal lattice exhibits more flexibility, as the coordination sphere of these analogues is less crowded. The IR absorbance frequencies of the hydroxide ligands correlate as a function of the Ln(3+) ionic radius. This corresponds well with the X-ray single

  19. Ligand-Free Synthesis of Tunable Size Ln:BaGdF5 (Ln = Eu3+ and Nd3+) Nanoparticles: Luminescence, Magnetic Properties, and Biocompatibility

    OpenAIRE

    Becerro, Ana Isabel; González-Mancebo, D.; Cantelar, Eugenio; Cussó, Fernando; Stepien, Grazyna; Fuente, J.M. de la; Ocaña, Manuel

    2016-01-01

    Bifunctional and highly uniform Ln:BaGdF5 (Ln = Eu3+ and Nd3+) nanoparticles have been successfully synthesized using a solvothermal method consisting of the aging at 120 °C of a glycerol solution containing the corresponding Lanthanide acetylacetonates and butylmethylimidazolium tetrafluoroborate. The absence of any surfactant in the synthesis process rendered hydrophilic nanospheres (with tunable diameter from 45 nm 85 nm, depending on the cations concentration of the starting solution) whi...

  20. Fabrication and luminescence properties of one-dimensional CaMoO(4): Ln(3+) (Ln = Eu, Tb, Dy) nanofibers via electrospinning process.

    Science.gov (United States)

    Hou, Zhiyao; Chai, Ruitao; Zhang, Milin; Zhang, Cuimiao; Chong, Peng; Xu, Zhenhe; Li, Guogang; Lin, Jun

    2009-10-20

    One-dimensional CaMoO(4):Ln(3+) (Ln = Eu, Tb, Dy) nanofibers have been prepared by a combination method of sol-gel and electrospinning process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL), and low voltage cathodoluminescence (CL) as well as kinetic decays were used to characterize the resulting samples. SEM and TEM analyses indicate that the obtained precursor fibers have a uniform size, and the as-formed CaMoO(4):Ln(3+) nanofibers consist of nanoparticles. Under ultraviolet excitation, the CaMoO(4) samples exhibit a blue-green emission band with a maximum at 500 nm originating from the MoO(4)(2-) groups. Due to an efficient energy transfer from molybdate groups to dopants, CaMoO(4):Ln(3+) phosphors show their strong characteristic emission under ultraviolet excitation and low-voltage electron beam excitation. The energy transfer process was further studied by the emission spectra and the kinetic decay curves of Ln(3+) upon excitation into the MoO(4)(2-) groups in the CaMoO(4):x mol % Ln(3+) samples (x = 0-5). Furthermore, the emission colors of CaMoO(4):Ln(3+) nanofibers can be tuned from blue-green to green, yellow, and orange-red easily by changing the doping concentrations (x) of Ln(3+) ions, making the materials have potential applications in fluorescent lamps and field emission displays (FEDs).

  1. Complexation of amidocarbamoyl phosphine oxides with Ln{sup +3} (Ln = La, Nd, Pm, Sm and Eu) cation series: structural and thermodynamical features

    Energy Technology Data Exchange (ETDEWEB)

    Hosseinnejad, Tayebeh; Kazemi, Tayebeh [Alzahra Univ., Tehran (Iran, Islamic Republic of). Dept. of Chemistry

    2016-05-01

    In the present study, we have mainly investigated the nature of interactions in Ln{sup 3+} (Ln = La, Nd, Pm, Sm, Eu) complexes with amidocarbamoyl methyl phosphine oxide (CMPO) and amidocarbamoyl propyl phosphine oxide (CPPO) ligands based on density functional theory (DFT) approaches. In the first step, thermodynamical properties for complexation of CMPO and CPPO ligands with Ln{sup 3+} cation series have been determined in the gas phase and with the presence of three solvents: n-hexane, chloroform and toluene, via polarized continuum model (PCM) computations. The trend of metal-ligand interaction strength has been analyzed and compared with the trend of ionic hardness within the series of lanthanide cations and different size of alkyl chain of amidocarbamoyl phosphine oxide ligand. The calculated thermochemical results in the gas and solution phases reveals that there is a consistency between increasing trend in the hardness of Ln{sup 3+} cation series and also electron-donating property of alkyl chain with increasing in thermodynamical stability of [Ln-CMPO]{sup 3+} and [Ln-CPPO]{sup 3+} complex series. We have also demonstrated that in the complexation reaction of all complex series, using n-hexane as solvent is more favorable thermodynamically than chloroform and toluene. It should be stated that this issue has been observed in many experiments. Finally, analysis of calculated deformation energies and also the variation in bond order of some selected key bonds in CMPO and CPPO ligands and their corresponded Ln{sup 3+} complexes series show a similar trend with increasing in the hardness of Ln{sup 3+} cation series and electron-donating of alkyl chain of amidocarbamoyl phosphine oxide ligand.

  2. COMPARISION OF THE COLOR PROPERTIES OF COMPOUNDS Ln2Ce2O7 AND Ln2CeZrO7

    Directory of Open Access Journals (Sweden)

    B. Hablovicova

    2015-09-01

    Full Text Available Pyrochlore type pigments Ln2Ce2O7 and Ln2CeZrO7 (Ln = Nd, Sm, Gd, Dy, Er, Yb and Y prepared by solid-state reaction were investigated. Effect of rare earths and zirconium ions and calcination temperature (1400, 1500 and 1600oC for Ln2Ce2O7 and 1400, 1450 and 1500 C for Ln2CeZrO7 on their color properties in organic matrix and ceramic glazes, particle size distribution and phase composition were evaluated. The most interesting shades achieve compounds with the highest calcination temperature. Their colors depend on used rare earth ions (shades change from green, cross yellow to pink in organic mass and from green, cross yellow-green to orange in ceramic glazes, while compounds without zirconium have better color properties. Pigments Ln2Ce2O7 calcined at 1600 C are single-phase (except Yb2Ce2O7.

  3. Vibrational spectra and structural considerations of compounds NaLnTiO4

    NARCIS (Netherlands)

    Blasse, G.; Heuvel, G.P.M. van den

    1974-01-01

    The Raman and infrared spectra of compounds NaLnTiO4 (Ln = lanthanide, including yttrium) are reported and discussed. Their most striking feature is a strong band in both spectra at about 900 cm−1. This band is ascribed to a vibration localized in the Ti---O bond directed towards the Na---O layers.

  4. Structural anomalies associated with the electronic and spin transitions in LnCoO(3)

    NARCIS (Netherlands)

    Knizek, K; Jirak, Z; Hejtmanek, J; Veverka, M; Marysko, M; Maris, G; Palstra, TTM; Knížek, K.; Maryško, M.

    2005-01-01

    A powder X-ray diffraction study, combined with magnetic susceptibility and electric transport measurements, was performed on a series of LnCoO(3) perovskites (Ln = Y, Dy, Gd, Sm, Nd, Pr and La) over a temperature range 100-1000 K. A non-standard temperature dependence of the observed thermal expans

  5. Salen-based [Zn2Ln3] complexes with fluorescence and single-molecule-magnet properties.

    Science.gov (United States)

    Burrow, Carolyn E; Burchell, Tara J; Lin, Po-Heng; Habib, Fatemah; Wernsdorfer, Wolfgang; Clérac, Rodolphe; Murugesu, Muralee

    2009-09-07

    A family of four isostructural complexes with a V-shaped pentanuclear [Zn(2)Ln(3)] core of general formula [Zn(2)Ln(3)(m-salen)(3)(N(3))(5)(OH)(2)] [Ln(III) = Tb(III) (1), Eu(III) (2), Ho(III) (3), Dy(III) (4); m-salen = N,N'-ethylenebis(3-methoxysalicylideneamine)] were isolated and structurally characterized. The fluorescence and magnetic measurements of the four compounds were investigated. Complex 1 exhibits strong fluorescence properties, while single-molecule-magnet behavior is seen in complex 4.

  6. Syntheses and Structures of the New Quaternary Rubidium Selenides Rb Ln2CuSe 4 ( Ln=Sm, Gd, Dy), Rb 1.5Ln2Cu 2.5Se 5 ( Ln=Gd, Dy), and RbSm 2Ag 3Se 5

    Science.gov (United States)

    Huang, Fu Qiang; Ibers, James A.

    2000-05-01

    Six quaternary rubidium selenides RbLn2CuSe4 (Ln=Sm, Gd, Dy), Rb1.5Ln2Cu2.5Se5 (Ln=Gd, Dy), and RbSm2Ag3Se5 have been synthesized at 1073 K with the use of a reactive flux of Rb2Se3. At 153 K all compounds contain four formula units in orthorhombic unit cells. The isostructural compounds RbLn2CuSe4 crystallize in space group Cmcm; the isostructural compounds Rb1.5Ln2Cu2.5Se5 crystallize in space group Pnnm; RbSm2Ag3Se5 crystallizes in space group Cmcm. The cells of RbLn2CuSe4 are (Ln, a, b, c (Å)): Sm, 4.1834(9), 14.308(3), 14.439(3); Gd, 4.1568(8), 14.227(3), 14.409(3); Dy, 4.1237(10), 14.083(4), 14.291(3), and the corresponding R1 indices for the refined structures are 0.023, 0.029, and 0.039. The cells of Rb1.5Ln2Cu2.5Se5 are: Gd, 16.243(3), 16.449(3), 4.0980(7); Dy, 16.120(3), 16.292(3), 4.0610(8), and the R1 indices are 0.036 and 0.043. The cell of RbSm2Ag3Se5 is 4.3223(6), 15.229(2), 17.420(3) Å and the R1 index is 0.025. All six are closely related three-dimensional tunnel structures. Their anionic frameworks are built from LnSe6 octahedra and MSe4 (M=Cu, Ag) tetrahedra. RbLn2CuSe4 contains infinite 1∞[CuSe3] chains of vertex-sharing tetrahedra; Rb1.5Ln2Cu2.5Se5 also contains infinite chains of tetrahedra; and the tunnel in RbSm2Ag3Se5 holds one Rb+ cation in a 10-membered ring consisting of six Ag-Se bonds and four Sm-Se bonds. Rb1.5Dy2Cu2.5Se5, which is paramagnetic, obeys the Curie-Weiss law and has an effective magnetic moment of 10.63(4) μB.

  7. An unusual cause for halitosis.

    Science.gov (United States)

    Bathgate, Gabriella; Ali, Haythem; Aboul Enein, Mohamed; Poynter, Liam

    2016-04-19

    This report describes an unusual cause for halitosis and an unusual treatment for the underlying problem. Halitosis is a symptom which can result from a diverse range of underlying pathologies, most frequently those affecting the oral cavity or respiratory tract. Uncommonly, it arises due to pathology within the upper gastrointestinal tract. The case of a patient presenting with severe persistent halitosis attributable to mesh erosion occurring 8 years after redo laparoscopic hiatus hernia repair is described. Full external healing of the erosion tract was observed such that no symptomatic oesophageal perforation resulted. Mesh erosion is typically managed with surgical intervention. In this case, the infected mesh was successfully removed endoscopically.

  8. PNBE-supported metallopolymer-type optical materials through grafting of Zn-Ln (Ln = Nd, Yb or Er) benzimidazole complex monomers with efficient NIR luminescence

    Science.gov (United States)

    Liu, Lin; Li, Hongyan; Feng, Weixu; Fu, Guorui; Lü, Xingqiang; Wong, Wai-Kwok; Jones, Richard A.

    2017-02-01

    Through the ring-opening metathesis polymerization (ROMP) of norbornene (NBE) with each of obtained allyl-containing complex monomers [Zn(L)2(Py)Ln(NO3)3] (Ln = La, 1; Nd, 2; Yb, 3; Er, 4 or Gd, 5; HL = 4-allyl-2-(1H-benzo[d]imidazol-2-yl)-6-methoxyphenol; Py = pyridine), a series of metallopolymers Poly(NBE-co-[Zn(L)2Ln(Py)(NO3)3)]) were obtained, respectively. Especially for Poly(NBE-co-2) and Poly(NBE-co-3), covalently-bonded grafting endows significantly improved physical properties including efficient NIR luminescence (ΦNdL = 0.63% and ΦYbL = 1.43%) in solid state.

  9. Performance analysis of a hybrid fingerprint extracted from optical coherence tomography fingertip scans

    CSIR Research Space (South Africa)

    Darlow, Luke N

    2016-06-01

    Full Text Available International Conference on Biometrics (ICB), 13-16 June 2016, Halmstad, Sweden Performance analysis of a hybrid fingerprint extracted from optical coherence tomography fingertip scans Darlow LN Connan J Singh A ABSTRACT: The Hybrid fingerprint is a...

  10. Synthesis, structure, and magnetism of a family of heterometallic {Cu2Ln7} and {Cu4Ln12} (Ln = Gd, Tb, and Dy) complexes: the Gd analogues exhibiting a large magnetocaloric effect.

    Science.gov (United States)

    Langley, Stuart K; Moubaraki, Boujemaa; Tomasi, Corrado; Evangelisti, Marco; Brechin, Euan K; Murray, Keith S

    2014-12-15

    The syntheses, structures, and magnetic properties of two heterometallic Cu(II)-Ln(III) (Ln(III) = Gd, Tb, and Dy) families, utilizing triethanolamine and carboxylate ligands, are reported. The first structural motif displays a nonanuclear {Cu(II)2Ln(III)7} metallic core, while the second reveals a hexadecanuclear {Cu(II)4Ln(III)12} core. The differing nuclearities of the two families stem from the choice of carboxylic acid used in the synthesis. Magnetic studies show that the most impressive features are displayed by the {Cu(II)2Gd(III)7} and {Cu(II)4Gd(III)12} complexes, which display a large magnetocaloric effect, with entropy changes -ΔSm = 34.6 and 33.0 J kg(-1) K(-1) at T = 2.7 and 2.9 K, respectively, for a 9 T applied field change. It is also found that the {Cu(II)4Dy(III)12} complex displays single-molecule magnet behavior, with an anisotropy barrier to magnetization reversal of 10.1 K.

  11. The A-Type Ln4N2S3 Series: New Nitride Sulfides of the Light Lanthanoids (Ln = Ce–Nd

    Directory of Open Access Journals (Sweden)

    Falk Lissner

    2016-12-01

    Full Text Available The reaction of lanthanoid metal powders (Ln with sulfur and cesium azide (CsN3 as a nitrogen source in the presence of lanthanoid tribromides (LnBr3 yields lanthanoid nitride sulfides with the composition Ln4N2S3 (Ln = Ce–Nd when appropriate molar ratios of the starting material are used. Additional cesium bromide (CsBr as a flux secures quantitative conversion (7 days at 900 °C in evacuated silica tubes as well as the formation of black single crystals. All compounds crystallize isotypically with the orthorhombic crystal structure of La4N2S3 (Pnnm, Z = 2 and their structures were determined from single-crystal X-ray diffraction data (Ce4N2S3: a = 644.31(4, b = 1554.13(9, c = 404.20(3 pm; Pr4N2S3: a = 641.23(4, b = 1542.37(9, c = 400.18(3 pm; Nd4N2S3: a = 635.19(4, b = 1536.98(9, c = 397.85(3 pm. Compared to La4N2S3 the a-axes do not fulfill the expectation of the lanthanide contraction. The main feature of the crystal structure comprises N3−-centered (Ln3+4 tetrahedra arranging as pairs [N2Ln6]12+ of edge-shared [NLn4]9+ units, which are further connected via four vertices to form double chains ∞ 1{([NLn4/2]26+}. Bundled along [001] like a hexagonal rod packing, they are held together by two crystallographically different S2− anions. Two compounds of a second modification (B-type La4N2S3 and Pr4N2S3 will also be presented and discussed for comparison.

  12. Research of Testing Technology About LN82530 Serial Communication Controler%LN82530串行通讯控制器测试技术研究

    Institute of Scientific and Technical Information of China (English)

    于祥苓; 冯蕊; 唐琳

    2004-01-01

    LN82530串行通讯控制器(SCC)是一种双通道、多重协议数据通讯外围接口电路.此电路包括复杂的内部功能,可当作串行-并行,并行-串行转换器/控制器.本文对LN82530内部各功能块的测试作了详细的研究,并对其直流测试中存在的某些问题的解决作了简要的介绍.

  13. Predictable self-assembled [2×2] Ln(III)4 square grids (Ln = Dy,Tb)-SMM behaviour in a new lanthanide cluster motif.

    Science.gov (United States)

    Anwar, Muhammad Usman; Thompson, Laurence Kenneth; Dawe, Louise Nicole; Habib, Fatemah; Murugesu, Muralee

    2012-05-14

    The ditopic carbohydrazone ligand (L1) produces the square, self-assembled [2×2] grids [Dy(4)(L1)(4)(OH)(4)]Cl(2) (1) and [Ln(4)(L1)(4)(μ(4)-O)(μ(2)-1,1-N(3))(4)] (Ln = Dy (2), Tb (3)), with 2 exhibiting SMM behaviour. Two relaxation processes occur with U(eff) = 51 K, 91 K in the absence of an external field, and one with U(eff) = 270 K in the presence of a 1600 Oe optimum field.

  14. Synthesis and conductivities of the garnet-related Li ion conductors, Li5Ln3Sb2O12 (Ln= La, Pr, Nd, Sm, Eu)

    OpenAIRE

    Percival, Julia; Kendrick, Emma; Slater, Peter

    2008-01-01

    In this paper the synthesis and conductivities of the garnet-related Li ion conductors, Li5Ln3Sb2O12 (Ln=La, Pr, Nd, Sm, Eu), are reported. These phases show high Li ion conductivity, similar to previously reported for the related Li5La3M2O12 (M=Nb, Ta) materials. Neutron diffraction structural studies are also reported for Li5La3Sb2O12 indicating a cubic unit cell, space group Ia-3d, with Li located in two partially occupied sites.

  15. Low-Temperature Transformations of Protonic Forms of Layered Complex Oxides HLnTiO4 and H2Ln2Ti3O10 (Ln = La, Nd

    Directory of Open Access Journals (Sweden)

    L. D. Abdulaeva

    2013-01-01

    Full Text Available In the present work protonic forms of layered n=1,3 Ruddlesden-Popper oxides HLnTiO4 and H2Ln2Ti3O10 (Ln = La, Nd were used as the starting point for soft chemistry synthesis of two series of perovskite-like compounds by acid leaching and exfoliation, promoted by vanadyl sulfate. The last route leads to the nanostructured VO2+ containing samples. Characterization by SEM, powder XRD, and TGA has been performed for the determination of the structure and composition of synthesized oxides.

  16. Plummer Vinson syndrome: unusual features.

    Science.gov (United States)

    Makharia, Govind K; Nandi, Bhaskar; Garg, Pramod K; Tandon, Rakesh K

    2002-01-01

    Plummer Vinson syndrome is a constellation of postcricoid esophageal webs, iron deficiency anemia, dysphagia and koilonychia. We describe some unusual manifestations in three patients with this syndrome; these were clubbing instead of koilonychia, tortuous esophagus in addition to presence of esophageal webs, and celiac disease.

  17. Pachyonychia congenita with unusual features.

    Science.gov (United States)

    Balasubramanian, S; Kaarthigeyan, K; Ramnath, B

    2009-10-01

    Pachyonychia congenita is a rare hereditary disorder characterized by gross thickening of all finger and toenails. We report an infant who had clinical features consistent with pachyonychia congenita type II, with unusual features of microcephaly, seizures, electroencephalogram abnormalities, failure to thrive, and heterochromia iridis.

  18. Unusual sutural bones at pterion

    Directory of Open Access Journals (Sweden)

    Nayak SB

    2008-08-01

    Full Text Available The existence of Wormian (sutural bones in the skull is well known. We found three unusual Wormian bones at the right pterion in an adult Indian skull. The variation noted was unilateral. This type of variation has not been reported yet.

  19. Pemphigus vegetans: An unusual presentation

    Directory of Open Access Journals (Sweden)

    Ashish Dhamija

    2012-01-01

    Full Text Available Pemphigus vegetans is a rare variant of pemphigus vulgaris that is characterized by vegetating lesions primarily in the flexures. We report a 45-year-old male patient with an unusual presentation of the disease. A careful analysis of the clinical and laboratory findings enabled us to reach a diagnosis and successfully treat the patient.

  20. Traditionally used medicinal plants against uncomplicated urinary tract infections: Are unusual, flavan-4-ol- and derhamnosylmaysin derivatives responsible for the antiadhesive activity of extracts obtained from stigmata of Zea mays L. against uropathogenic E. coli and Benzethonium chloride as frequent contaminant faking potential antibacterial activities?

    Science.gov (United States)

    Rafsanjany, Nasli; Sendker, Jandirk; Lechtenberg, Matthias; Petereit, Frank; Scharf, Birte; Hensel, Andreas

    2015-09-01

    The dried stigmata from Zea mays L. are used traditionally for the treatment of uncomplicated urinary tract infections. A recent screening has indicated that hydroalcoholic extract of the herbal material inhibits the adhesion of uropathogenic Escherichia coli (UPEC) to T24 bladder cells. For verification of these data EtOH-water (1:1) extracts from 4 different batches of Maydis stigmata were investigated. Within an in vitro adhesion assay (UPEC strain 2980 and human T24 bladder cells) a dose-dependent antiadhesive activity against UPEC was verified (IC50 1040μg/mL). Bioassay guided fractionation of M. stigmata, batch S1, by EtOH-water extraction, followed by chromatography on Sephadex LH20 revealed two active fractions (I and XI). Further purification of fraction I and structure elucidation of the isolated compound revealed the presence of significant amounts of the biocide benzethonium chloride as contaminant. Benzethonium chloride was also identified in subsequent investigations in 2 different batches of M. stigmata. The presence of such nondeclared and illegal contaminants in the herbal raw material market has to be discussed intensively. From benzethonium-free raw material (batch S2) as well as from batch S1 fraction XI was further fractionated by MPLC and preparative HPLC, leading to a still complex subfraction XIG, which was analyzed by UHPLC/+ESI-QTOF-MS analysis. Advanced data processing and species-metabolite relationship database revealed the tentatively existence of the unusual C-glycosidic flavones derhamnosylmaysin (6), 3'-deoxyrhamnosylmaysin (4), 3'-O-methylderhamnosylmaysin (3), apiferol (2) and alternanthin (8) which might be related to the antiadhesive activity of this subfraction against UPEC.

  1. Mechanical Properties and Defective Effects of 316LN Stainless Steel by First-Principles Simulations

    Institute of Scientific and Technical Information of China (English)

    X.Q. Li; J.J. Zhao; J.C. Xu; X. Liu

    2011-01-01

    In current International Thermonuclear Experimental Reactor (ITER) design, the 316LN austenitic stainless steel (316LN SS) is used for first-wall/blanket structures. Thus, it is necessary to study the fundamental mechanical properties and irradiation effect of 316LN SS. A random solid solution model of Fe-Cr-Ni-Mn- Mo-Si alloy is used for describing 310LN S$. Using first-principles approaches, the elastic constants and ideal strength of the alloy were calculated. Such alloy exhibits good ductile behavior according to the theoretical values of Cauchy pressure and ratio of bulk modulus and shear modulus. Within the 256-atom supercell, inclusion of single vacancy defect further enhances the ductility of the alloy, and the existence of interstitial (Fe, H, He) atoms enhances the Young's modulus.

  2. Design and validation of the high performance and low noise CQU-DTU-LN1 airfoils

    DEFF Research Database (Denmark)

    Cheng, Jiangtao; Zhu, Wei Jun; Fischer, Andreas

    2014-01-01

    with the blade element momentum theory, the viscous-inviscid XFOIL code and an airfoil self-noise prediction model, an optimization algorithm has been developed for designing the high performance and low noise CQU-DTU-LN1 series of airfoils with targets of maximum power coefficient and low noise emission......This paper presents the design and validation of the high performance and low noise Chong Qing University and Technical University of Denmark LN1 (CQU-DTU-LN1) series of airfoils for wind turbine applications. The new design method uses target characteristics of wind turbine airfoils in the design...... emission between the CQU-DTU-LN118 airfoil and the National Advisory Committee for Aeronautics (NACA) 64618 airfoil, which is used in modern wind turbine blades, are carried out. Copyright © 2013 John Wiley & Sons, Ltd....

  3. Structurally characterized luminescent lanthanide zinc carboxylate precursors for Ln-Zn-O nanomaterials.

    Science.gov (United States)

    Boyle, Timothy J; Raymond, Rebecca; Boye, Daniel M; Ottley, Leigh Anna M; Lu, Ping

    2010-09-14

    A novel family of lanthanide zinc carboxylate compounds was synthesized, characterized (structural determination and luminescent behavior), and investigated for utility as single-source precursors to Ln-Zn-O nanoparticles. Carboxylic acids [H-ORc = H-OPc (H-O(2)CCH(CH(3))(2), H-OBc (H-O(2)CC(CH(3))(3), H-ONc (H-O(2)CCH(2)C(CH(3))(3))] were individually reacted with diethyl zinc (ZnEt(2)) to yield a set of previously unidentified zinc carboxylates: (i) [Zn(mu-ORc)(3)Zn(mu-ORc)](n) [ORc = OPc (1), ONc (2)], (ii) [(py)Zn](2)(mu-ORc)(4) [ORc = OBc (3), ONc (4), and py = pyridine], or (iii) Zn(ORc)(2)(solv)(2) [ORc/solv = OPc/py (5), O(c)Nc/H(2)O (6) (O(c)Rc = chelating)]. Introduction of lanthanide cation [Ln[N(SiMe(3))(2)](3), ZnEt(2), and HOBc in py] yielded the mixed cationic species structurally characterized as: (i) (O(c)Bc)Ln[(mu-OBc)(3)Zn(py)](2) [Ln = Pr (7), Nd (8), Sm (9)] or (ii) (py)(2)Zn(mu-OBc)(3)Ln(O(c)Bc)(2)(py) [Ln = Tb (10), Dy (11), Er (12), Y (13), Yb (14)]. Exploration of alternative starting materials [Ln(NO(3))(3).nH(2)O, Zn(O(2)CCH(3))(2), HOBc in py] led to the isolation of (NO(3)(c))Ln[(mu-OBc)(3)Zn(py)](2) [Ln = La (15), Ce (16), Pr (17), Nd (18), Sm (19), Eu (20), Gd (21), Tb (22) Dy (23), and Er (24); NO(3)(c) = chelating]. The UV-vis spectra of 7-24 revealed standard absorption spectra for the Ln cations. Representative compounds were used to generate nanoparticles from an established 1,4-butanediol-based solution precipitation route. The nanoproducts isolated adopted either a mixed zincite/lanthanum oxide (18n or 22n) or pure zincite (8n or 10n) phase dependent on NO(3) or OBc moiety. Fluorescence was not observed for any of these nanomaterials possibly due to phase separation, low crystallinity, surface traps, and/or quenching based on elevated Ln cation content.

  4. The Voltage Boost Enabled by Luminescence Extraction in Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Ganapati, Vidya; Steiner, Myles A.; Yablonovitch, Eli

    2016-11-21

    A new physical principle has emerged to produce record voltages and efficiencies in photovoltaic cells, 'luminescence extraction.' This is exemplified by the mantra 'a good solar cell should also be a good LED.' Luminescence extraction is the escape of internal photons out of the front surface of a solar cell. Basic thermodynamics says that the voltage boost should be related to concentration ratio, C, of a resource by ..delta..V=(kT/q)ln{C}. In light trapping, (i.e. when the solar cell is textured and has a perfect back mirror) the concentration ratio of photons C={4n2}, so one would expect a voltage boost of ..delta..V=kT ln{4n2} over a solar cell with no texture and zero back reflectivity, where n is the refractive index. Nevertheless, there has been ambiguity over the voltage benefit to be expected from perfect luminescence extraction. Do we gain an open circuit voltage boost of ..delta..V=(kT/q)ln{n2}, ..delta..V=(kT/q)ln{2n2}, or ..delta..V=(kT/q)ln{4n2}? What is responsible for this voltage ambiguity ..delta..V=(kT/q)ln{4}=36mVolts? We show that different results come about, depending on whether the photovoltaic cell is optically thin or thick to its internal luminescence. In realistic intermediate cases of optical thickness the voltage boost falls in between; ln{n2}q..delta..V/kT)<;ln{4n2}.

  5. Phase relationships and materials design in the Ln-Si-Al-O-N system

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Subsolidus phase relationships in the system Ln2O3-Si3N4-AlN-Al2O3, where Ln represents Nd, Sm and Dy, were summarized, with emphasis on the region involving α-sialon, β-sialon and AlN-polytypoid phases. This information is further used in designing the compatible matrix phases of sialon materials with desirable properties. Examples were provided to illustrate the advantage of such a basic approach to materials design.

  6. SYNTHESES AND STRUCTURES OF AGLNS2 (LN=SM-YB) COMPOUNDS

    NARCIS (Netherlands)

    VANDERLEE, A; VANDEBELT, R; WIEGERS, GA

    1992-01-01

    The ternary compounds AgLnS2 (Ln = Sm-Yb) have been synthesized and characterized. It has been found, in accordance with a previous study, that all compounds, except AgYbS2, are monoclinic with a almost-equal-to b almost-equal-to 7.7 angstrom, c almost-equal-to 12 angstrom and 90-degrees

  7. Heterotrimetallic coordination polymers: {Cu(II)Ln(III)Fe(III)} chains and {Ni(II)Ln(III)Fe(III)} layers: synthesis, crystal structures, and magnetic properties.

    Science.gov (United States)

    Alexandru, Maria-Gabriela; Visinescu, Diana; Andruh, Marius; Marino, Nadia; Armentano, Donatella; Cano, Joan; Lloret, Francesc; Julve, Miguel

    2015-03-27

    The use of the [Fe(III) (AA)(CN)4](-) complex anion as metalloligand towards the preformed [Cu(II) (valpn)Ln(III)](3+) or [Ni(II) (valpn)Ln(III) ](3+) heterometallic complex cations (AA=2,2'-bipyridine (bipy) and 1,10-phenathroline (phen); H2 valpn=1,3-propanediyl-bis(2-iminomethylene-6-methoxyphenol)) allowed the preparation of two families of heterotrimetallic complexes: three isostructural 1D coordination polymers of general formula {[Cu(II) (valpn)Ln(III) (H2O)3 (μ-NC)2 Fe(III) (phen)(CN)2 {(μ-NC)Fe(III) (phen)(CN)3}]NO3 ⋅7 H2O}n (Ln=Gd (1), Tb (2), and Dy (3)) and the trinuclear complex [Cu(II) (valpn)La(III) (OH2 )3 (O2 NO)(μ-NC)Fe(III) (phen)(CN)3 ]⋅NO3 ⋅H2O⋅CH3 CN (4) were obtained with the [Cu(II) (valpn)Ln(III)](3+) assembling unit, whereas three isostructural heterotrimetallic 2D networks, {[Ni(II) (valpn)Ln(III) (ONO2 )2 (H2 O)(μ-NC)3 Fe(III) (bipy)(CN)]⋅2 H2 O⋅2 CH3 CN}n (Ln=Gd (5), Tb (6), and Dy (7)) resulted with the related [Ni(II) (valpn)Ln(III) ](3+) precursor. The crystal structure of compound 4 consists of discrete heterotrimetallic complex cations, [Cu(II) (valpn)La(III) (OH2)3 (O2 NO)(μ-NC)Fe(III) (phen)(CN)3 ](+), nitrate counterions, and non-coordinate water and acetonitrile molecules. The heteroleptic {Fe(III) (bipy)(CN)4} moiety in 5-7 acts as a tris-monodentate ligand towards three {Ni(II) (valpn)Ln(III)} binuclear nodes leading to heterotrimetallic 2D networks. The ferromagnetic interaction through the diphenoxo bridge in the Cu(II)-Ln(III) (1-3) and Ni(II)-Ln(III) (5-7) units, as well as through the single cyanide bridge between the Fe(III) and either Ni(II) (5-7) or Cu(II) (4) account for the overall ferromagnetic behavior observed in 1-7. DFT-type calculations were performed to substantiate the magnetic interactions in 1, 4, and 5. Interestingly, compound 6 exhibits slow relaxation of the magnetization with maxima of the out-of-phase ac signals below 4.0 K in the lack of a dc field, the values of the pre

  8. Syntheses, characterization, and luminescence of two lanthanide complexes [Ln2(acetate)6(H2O)4]·4H2O (Ln=Tb(1), Sm(2))

    Institute of Scientific and Technical Information of China (English)

    YU Qiongyan; ZHOU Xiuxia; LIU Maosheng; CHEN Jianqiao; ZHOU Zhengyuan; YIN Xia; CAI Yuepeng

    2008-01-01

    Two dinuclear compounds [Ln2(acetate)6(H2O)4]·4H2O (Ln=Tb(1), Sm(2)) were obtained by the hydrothermal reaction of Ln2O3 with malonic acid at 150 ℃. Both compounds were characterized by elemental analyses, infrared spectra, and single crystal X-ray diffraction. The results showed that complexes 1 and 2 were isomorphous and crystallize in triclinic space group P(-1). The coordination geometry around Ln(III) ions in the complexes 1 and 2 was a distorted tricapped trigonal prism with a nine coordination. In the crystal, the molecular organization was further stabilized by well-defined weak hydrogen bonding interactions between the neutral dinuclear molecular units that led to the formation of a three-dimensional network. The fluorescence properties of the two complexes 1 and 2 in organic solvents were also studied. The results show that the ligand acetate favored energy transfer to the emitting energy level of Tb(III) in complex 1. Some factors that influence the fluorescent intensity were also discussed in the article.

  9. Analýza modálních vlastností vertikálního synchronního generátoru

    OpenAIRE

    Kornherr, Milan

    2012-01-01

    Diplomová práce se zabývá analýzou modálních vlastností synchronního vertikálního generátoru. Cílem práce je určení vlivu jednotlivých částí generátoru na modální vlastnosti. Analyzována je kostra generátoru, rotor a celý generátor. Další část práce se zabývá analýzou různých variant uložení generátoru a také konstrukčních úprav, které vedou ke zlepšení modálních vlastností. Výpočtové modelování bylo provedeno v programu ANSYS. This Master´s thesis deals with the analysis of modal characte...

  10. Rapid microwave-assisted sol-gel preparation of Pd-substituted LnFeO3 (Ln = Y, La): phase formation and catalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Misch, Lauren M.; Birkel, Alexander; Figg, C. Adrian; Fors, Brett P.; Hawker, Craig J.; Stucky, Galen D.; Seshadri, Ram [UCSB

    2014-02-13

    We present a rapid microwave-assisted sol–gel approach to Pd-substituted LnFeO3 (Ln = Y, La) for applications in C–C coupling reactions. These materials could be prepared in household microwave ovens in less than 15 minutes of reaction time with the final materials displaying well-defined structure and morphology. Phase evolution was studied using time-dependent microwave heatings and then compared with the results obtained from thermogravimetric analyses. Materials were confirmed to be phase pure by laboratory and synchrotron X-ray diffraction. Substituted Pd is ionic as shown by the binding energy shift from X-ray photoelectron spectroscopy. The short heating periods required for phase purity allow these materials less time for sintering as compared to conventional solid state preparation methods, making relatively high surface areas achievable. These materials have been successfully used as catalyst precursor materials for C–C coupling reactions in which the active species is Pd0. Pd-substituted LnFeO3 (Ln = Y, La) provides Pd0 in solution which can be complexed by the ligand SPhos, allowing for aryl chloride coupling.

  11. Synthesis and photophysical properties of Ir~Ⅲ-Ln~Ⅲ(Ln=Nd,Yb,Er) bimetallic complexes containing bipyrimidines as bridging ligands

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Bipyrimidines have been chosen as(NN)(NN) bridging ligands for connecting metal centers.IrⅢ-LnⅢ(Ln = Nd,Yb,Er) bimetallic complexes [Ir(dfppy)2(μ-bpm)Ln(TTA)3]Cl were synthesized by using Ir(dfppy)2(bpm)Cl as the ligand coordinating to lanthanide complexes Ln(TTA)3·2H2O.The stability constants between Ir(dfppy)2(bpm)Cl and lanthanide ions were measured by fluorescence titration.The obvious quenching of visible emission from IrⅢ complex in the IrⅢ-LnⅢ(Ln = Nd,Yb,Er) bimetallic complexes indicates that energy transfer occurred from IrⅢ center to lanthanides.NIR emissions from NdⅢ,YbⅢ,and ErⅢ were obtained under the excitation of visible light by selective excitation of the IrⅢ-based chromophore.It was proven that Ir(dfppy)2(bpm)Cl as the ligand could effectively sensitize NIR emission from NdⅢ,YbⅢ,and ErⅢ.

  12. Infrared and Raman spectra of tris(dipivaloylmethanato) lanthanides, Ln(thd)3 (Ln = La, Nd, Eu, Gd, Tb, Ho, Er, Tm, Yb, Lu)

    Science.gov (United States)

    Belova, Natalya V.; Sliznev, Valery V.; Christen, Dines

    2017-03-01

    The infrared and Raman vibrational spectra of the series of solid tris(dipivaloylmethanato) lanthanides, Ln(thd)3 (Ln = La, Nd, Eu, Gd, Tb, Ho, Er, Tm, Yb, Lu), have been recorded at room temperature over wide ranges (4000-50 cm-1 and 3500-80 cm-1, respectively). The experimental spectra obtained in the present study were successfully assigned based on the quantum chemical calculations (DFT/PBE0) performed for the monomer Ln(thd)3 molecules. The experimental vibrational spectra for all complexes studied are rather similar as are the theoretical simulations. The data analysis shows that the main contributions to vibrational modes arise from the vibrations of the ligand possessing practically the same geometry for all complexes. According to the calculation results the structure of the coordination polyhedron is increasingly distorted in the series from La(thd)3 to Lu(thd)3. Although the contributions of the polyhedron vibrations in vibrational modes are not predominant, there is rise in the frequencies associated with vibrations of the coordination polyhedron LnO6 in this series. This increase has been explained by the concept of lanthanide contraction.

  13. Covalently-bonded grafting of [Ln3(Benzimidazole)4]-arrayed (Ln = Tb, Nd, Yb or Er) complex monomers into PNBE (poly(norbornene)) with highly luminous color-purity green-light or efficient NIR luminescence

    Science.gov (United States)

    Liu, Lin; Fu, Guorui; Feng, Heini; Guan, Jiaqing; Li, Fengping; Lü, Xingqiang; Wong, Wai-Kwok; Jones, Richard A.

    2017-07-01

    Within series of Ln3-grafted polymers Poly({[Ln3(L)4(NO3)6]·(NO3)·(H3O)2}-co-NBE) (Ln = La, 1; Ln = Eu, 2; Ln = Tb, 3; Ln = Nd, 4; Ln = Yb, 5; Ln = Er, 6 or Ln = Gd, 7) obtained from ring-opening metathesis polymerization (ROMP) of norbornene (NBE) with each of allyl-functionalized complex monomers {[Ln3(L)4(NO3)6]·(NO3)·(H3O)2} (HL = 4-allyl-2-(1H-benzo[d]imidazol-2-yl)-6-methoxyphenol), PNBE-assisted effective energy transfer renders Poly(3-co-NBE) Tb3+-centered highly luminous color-purity green-light with an attractive quantum yield of 87% and efficient near-infrared (NIR) luminescence (ΦNdL = 0.61%; ΦYbL = 1.47% and ΦErL = 0.03%) for Nd3+-, Yb3+- or Er3+-grafted polymers.

  14. Syntheses and Structures of the Quaternary Copper Tellurides K 3Ln4Cu 5Te 10 ( Ln=Sm, Gd, Er), Rb 3Ln4Cu 5Te 10 ( Ln=Nd, Gd), and Cs 3Gd 4Cu 5Te 10

    Science.gov (United States)

    Huang, Fu Qiang; Ibers, James A.

    2001-09-01

    Six quaternary alkali-metal rare-earth copper tellurides K3Ln4Cu5Te10 (Ln=Sm, Gd, Er), Rb3Ln4Cu5Te10 (Ln=Nd, Gd), and Cs3Gd4Cu5Te10 have been synthesized at 1123 K with the use of reactive fluxes of alkali-metal halides ACl (A=K, Rb, Cs). All crystallographic data were collected at 153 K. These compounds crystallize in space group Pnnm of the orthorhombic system with two formula units in cells of dimensions (A3Ln4, a, b, c (Å)): K3Sm4, 16.590(2), 17.877(2), 4.3516(5); K3Gd4, 16.552(4), 17.767(4), 4.3294(9); K3Er4, 16.460(4), 17.550(4), 4.2926(9); Rb3Nd4, 17.356(1), 17.820(1), 4.3811(3); Rb3Gd4, 17.201(2), 17.586(2), 4.3429(6); Cs3Gd4, 17.512(1), 17.764(1), 4.3697(3). The corresponding R1 indices for the refined structures are 0.0346, 0.0315, 0.0212, 0.0268, 0.0289, and 0.0411. The three K3Ln4Cu5Te10 structures belong to one structure type and the Rb3Ln4Cu5Te10 (Ln=Nd, Gd) and Cs3Gd4Cu5Te10 structures belong to another one, the difference being the location of one of the three unique Cu atoms. Both structure types are three-dimensional tunnel structures that contain similar Ln/Te fragments built from LnTe6 octahedra and CuTe4 tetrahedra. The CuTe4 tetrahedra form 1∞[CuTe5-3] and 1∞[CuTe3-2] chains. The alkali-metal atoms, which are in the tunnels, are coordinated to seven or eight Te atoms.

  15. Influence of Tuned Linker Functionality on Modulation of Magnetic Properties and Relaxation Dynamics in a Family of Six Isotypic Ln2 (Ln = Dy and Gd) Complexes.

    Science.gov (United States)

    Mukherjee, Soumya; Lu, Jingjing; Velmurugan, Gunasekaran; Singh, Shweta; Rajaraman, Gopalan; Tang, Jinkui; Ghosh, Sujit K

    2016-11-07

    A coordination complex family comprising of six new dinuclear symmetric lanthanide complexes, namely, [Ln2(Lx)2(L')2(CH3OH)2]·yG (H2Lx: three related yet distinct Schiff-base linkers; x = 1-3, according to the nomenclature of the Schiff-base linker employed herein. HL': 2,6-dimethoxyphenol. yG refers to crystallographically assigned guest solvent species in the respective complexes; y = number of solvent molecules; Ln(III) = Dy/Gd) were isolated employing a mixed-ligand strategy stemming out of a strategic variation of the functionalities introduced among the constituent Schiff-base linkers. The purposeful introduction of three diverse auxiliary groups with delicate differences in their electrostatic natures affects the local anisotropy and magnetic coupling of Ln(III) ion-environment in the ensuing Ln2 dinuclear complexes, consequentially resulting into distinctly dynamical magnetic behaviors among the investigated new-fangled family of isotypic Ln2 complexes. Among the entire family, subtle alterations in the chemical moieties render two of the Dy2 analogues to behave as single molecule magnets, while the other Dy2 congener merely exhibits slow relaxation of the magnetization. The current observation marks one of the rare paradigms, wherein magnetic behavior modulation was achieved by virtue of the omnipresent influence of subtly tuned linker functionalities among the constituent motifs of the lanthanide nanomagnets. To rationalize the observed difference in the magnetic coupling, density functional theory and ab initio calculations (CASSCF/RASSI-SO/POLY_ANISO) were performed on all six complexes. Subtle difference in the bond angles leads to difference in the J values observed for Gd2 complexes, while difference in the tunnel splitting associated with the structural alterations lead to variation in the magnetization blockade in the Dy2 complexes.

  16. Pillared metal(IV) phosphate-phosphonate extraction of actinides

    Energy Technology Data Exchange (ETDEWEB)

    Burns, J.D.; Clearfield, A. [Texas A and M Univ., College Station, TX (United States). Dept. of Chemistry; Borkowski, M.; Reed, D.T. [Los Alamos National Laboratory, Carlsbad, NM (United States). Earth and Environmental Sciences Div.

    2012-07-01

    Four pillared metal(IV) phosphate-phosphonate ion exchange materials were synthesized and characterized. Studies were conducted to determine their affinity for the lanthanides (Ln's) and actinides (An's). It was determined that by simply manipulating the metal source (Zr or Sn) and the phosphate source (H{sub 3}PO{sub 4} or Na{sub 3}PO{sub 4}) large differences were seen in the extraction of the Ln and An species. K{sub d} values higher than 4 x 10{sup 5} were observed for the AnO{sub 2}{sup 2+} species in nitric acid at pH 2. These basic uptake experiments are important, as the data they provide may indicate the possibility of a separation of Ln's from An's or even more notably americium from curium and Ln's. (orig.)

  17. Phase transformations during HLnTiO4 (Ln=La, Nd) thermolysis and photocatalytic activity of obtained compounds

    Science.gov (United States)

    Silyukov, Oleg I.; Abdulaeva, Liliia D.; Burovikhina, Alena A.; Rodionov, Ivan A.; Zvereva, Irina A.

    2015-03-01

    Layered HLnTiO4 (Ln=La, Nd) compounds belonging to Ruddlesden-Popper phases were found to form partially hydrated compounds Ln2Ti2O7·xH2O during thermal dehydration as well as defect oxides Ln2□Ti2O7 as final products. Further heating of metastable defect Ln2□Ti2O7 substances leads to the formation of pyrochlore-type oxides Ln2Ti2O7 (p), with subsequent transformation under higher temperatures to stable layered 110-type perovskites Ln2Ti2O7. The occurring structure transformations lead to an increase of photocatalytic activity in the order of HLnTiO4<Ln2Ti2O7·yH2O<Ln2□Ti2O7<Ln2Ti2O7 (p)<Ln2Ti2O7 in the reaction of hydrogen evolution from aqueous isopropanol solution.

  18. An unusual bifid first metacarpal

    Directory of Open Access Journals (Sweden)

    Kumar Suresh

    2010-01-01

    Full Text Available Bifid first metacarpal is a common congenital anomaly. Here, we report an unusual case of bifid first metacarpal in a 13-year-old girl who presented with swan neck deformity of left thumb, a bony prominence on ulnar aspect of left thumb in the first web space and a bifid first metacarpal lacking its own epiphysis. The patient underwent surgery, resulting in complete functional recovery as well as cosmetic improvement of the left thumb.

  19. Unusual presentation of Lynch Syndrome

    Directory of Open Access Journals (Sweden)

    Yu Veronica PCC

    2009-06-01

    Full Text Available Abstract Lynch Syndrome/HNPCC is a syndrome of cancer predisposition linked to inherited mutations of genes participating in post-replicative DNA mismatch repair (MMR. The spectrum of cancer associated with Lynch Syndrome includes tumours of the colorectum, endometrium, ovary, upper gastrointestinal tract and the urothelium although other cancers are rarely described. We describe a family of Lynch Syndrome with an hMLH1 mutation, that harbours an unusual tumour spectrum and its diagnostic and management challenges.

  20. Aggressive Angiomyxoma: an Unusual Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Geng, Jun Zu; Cao, Bo Feng; Wang, Li Ping [The Image Center of Yantai Yuhuangding Hospital, Yantai (China)

    2012-01-15

    Aggressive angiomyxoma is an uncommon mesenchymal myxoid tumor that is characterized by slow growth and frequent local recurrence. It is currently regarded as a nonmetastasizing tumor. We describe a case of recurrent aggressive angiomyxoma with invasion into the veins including the inferior vena cava and the right atrium and with pulmonary metastases. Our case, together with those unusual cases documented in previous reports, may lead to a reappraisal of the nature of aggressive angiomyxoma.

  1. Unusual coloration in scarabaeid beetles

    Energy Technology Data Exchange (ETDEWEB)

    Brink, D J [Department of Physics, University of Pretoria, Pretoria 0002 (South Africa); Berg, N G van der [Department of Physics, University of Pretoria, Pretoria 0002 (South Africa); Prinsloo, L C [Department of Physics, University of Pretoria, Pretoria 0002 (South Africa); Hodgkinson, I J [Department of Physics, University of Otago, Dunedin (New Zealand)

    2007-04-07

    In this paper we investigate the reflection of circularly polarized light from the exocuticle of the scarabaeid beetle Gymnopleurus virens. Reflection spectra are deeply modulated, exhibiting a number of relatively narrow well-defined peaks, which differ from previously studied specimens. By comparing model calculations and electron microscopy work with the recorded spectra, we can propose the presence of specific structural defects responsible for the unusual spectra.

  2. Unusual coloration in scarabaeid beetles

    Science.gov (United States)

    Brink, D. J.; van der Berg, N. G.; Prinsloo, L. C.; Hodgkinson, I. J.

    2007-04-01

    In this paper we investigate the reflection of circularly polarized light from the exocuticle of the scarabaeid beetle Gymnopleurus virens. Reflection spectra are deeply modulated, exhibiting a number of relatively narrow well-defined peaks, which differ from previously studied specimens. By comparing model calculations and electron microscopy work with the recorded spectra, we can propose the presence of specific structural defects responsible for the unusual spectra.

  3. Unusual presentation of gallbladder perforation

    OpenAIRE

    Jayasinghe, G.; Adam, J.; Abdul-Aal, Y.

    2016-01-01

    Introduction: Gall bladder perforation is associated with high mortality rates and therefore must be recognised and managed promptly. We present an unusual presentation of spontaneous gall bladder perforation. Case presentation: An elderly lady with multiple medical co-morbidities was admitted with sepsis following a fall. Initial assessment lead to a diagnosis of pneumonia, however a rapidly expanding right flank mass was incidentally noted during routine nursing care. Imaging studies wer...

  4. Unusual presentation of cutaneous leiomyoma

    Directory of Open Access Journals (Sweden)

    Sapnashree Bhaskar

    2014-01-01

    Full Text Available Herein, we report a case of leiomyoma cutis because of its rarity and unusual presentation. The case presented with a solitary leiomyoma lesion which was painless. However, the adjacent normal appearing area was tender. A biopsy of the lesion as well as of a portion of the adjacent normal appearing area was taken, which confirmed the diagnosis of cutaneous leiomyoma. This may suggest the dormant nature of the disease which has not yet become apparent.

  5. Unusual Presentation of Cutaneous Leiomyoma

    Science.gov (United States)

    Bhaskar, Sapnashree; Jaiswal, Ashok K; Madhu, SM; Santosh, KV

    2014-01-01

    Herein, we report a case of leiomyoma cutis because of its rarity and unusual presentation. The case presented with a solitary leiomyoma lesion which was painless. However, the adjacent normal appearing area was tender. A biopsy of the lesion as well as of a portion of the adjacent normal appearing area was taken, which confirmed the diagnosis of cutaneous leiomyoma. This may suggest the dormant nature of the disease which has not yet become apparent. PMID:25484434

  6. Unusual variant of Cantrell's pentalogy?

    OpenAIRE

    Kumar, Basant; Sharma, S.B.; Kandpal, Deepak K.; Agrawal, L. D.

    2008-01-01

    A 12-hour-old male infant presented with prolapsed abdominal content through a defect on left side of chest wall with respiratory distress. A thorough clinical examination suggested absence of ectopia cordis, abdominal wall defect, and any bony anomaly. The child expired after 6 hours of admission because of respiratory distress and electrolyte imbalance. Is congenital defect of chest wall associated with diaphragmatic hernia without ectopia cordis and omphalocele, an unusual variant of Cantr...

  7. Structures and magnetic properties of double perovskites A sub 2 LnMO sub 6 and 6H-perovskites Ba sub 3 LnRu sub 2 O sub 9 (A=Sr, Ba; Ln=Y, lanthanides; M=Nb, Ta, Ru)

    CERN Document Server

    Hinatsu, Y

    2003-01-01

    This account describes the synthesis, crystal structures and magnetic properties of double perovskites A sub 2 LnMO sub 6 and 6H-perovskites Ba sub 3 LnRu sub 2 O sub 9 (A=Sr, Ba; Ln=Y, lanthanides; M=Nb, Ta, Ru). The double perovskites A sub 2 LnMO sub 6 have two kinds of cations, Ln and M, in the B site of the perovskite ABO sub 3. These cations adopt the alternative ordered arrangement. Measurements of the magnetic susceptibility, specific heat, and powder neutron diffraction showed that all of the A sub 2 LnRuO sub 6 compounds exhibited an antiferromagnetic transition at low temperatures and a complex temperature dependence of the magnetic susceptibility below their transition temperatures. In these compounds, the magnetic interaction between the Ln (4f electrons) and Ru (4d electrons) ions via the Ln-O-Ru pathway contributes greatly to their magnetic cooperative phenomena. The structural and magnetic studies for the 6H-perovskites Ba sub 3 LnRu sub 2 O sub 9 show that the Ln cations occupy the corner-sha...

  8. Influence of the crystal structure on the stability of Ln{sup 2+} in strontium borates

    Energy Technology Data Exchange (ETDEWEB)

    Dotsenko, V.P. [Physico-Chemical Institute, Ukrainian Academy of Sciences, 86 Lustdorfskaya str., 65080 Odesa (Ukraine)], E-mail: ssclab@ukr.net; Berezovskaya, I.V.; Efryushina, N.P. [Physico-Chemical Institute, Ukrainian Academy of Sciences, 86 Lustdorfskaya str., 65080 Odesa (Ukraine); Voloshinovskii, A.S.; Stryganyuk, G.B. [Ivan Franko National University of Lviv, 8 Kyryla i Mefodiya str., 29005 Lviv (Ukraine)

    2007-04-15

    The results of luminescence measurements on Ln (Eu, Yb) doped alkaline earth (M=Ca,Sr) borates M{sub 3}(BO{sub 3}){sub 2}, MB{sub 2}O{sub 4}, M{sub 2}B{sub 5}O{sub 9}X(X=Cl,Br), MB{sub 6}O{sub 10}, MB{sub 4}O{sub 7} after high-temperature annealing in various atmospheres are reported and discussed. The stability of Ln{sup 2+}(Ln=Eu,Yb) is found to increase in the sequence Sr{sub 3}(BO{sub 3}){sub 2}Ln{sup 3+}. A simple criterion is proposed to predict the stability of Ln{sup 2+} in alkaline earth borates.

  9. Vliv sociálních sítí na komunikaci a kulturu

    OpenAIRE

    Havlíček, Lukáš

    2015-01-01

    Má bakalářská práce je zaměřena na problematiku sociálních sítí a jejich vliv na dnešní společnost. Zabývá se jejich historií od prvotních pokusů až po nejnovější globální sociání sítě. Poté práce vysvětluje základní myšlenku vedoucí k vytvoření sociálních sítí i jejich charakteristické znaky. Dále nastiňuje problémy související se snadnou dostupností a nadměrným využíváním sociálních sítí, které následně ovlivňuje lidskou společnost. Práce se věnuje vlivu sociálních sítí na jazyk, mezilidsko...

  10. Fabrication of Ln-MOFs with color-tunable photoluminescence and sensing for small molecules

    Science.gov (United States)

    Wang, Shengyan; Shan, Liang; Fan, Yong; Jia, Jia; Xu, Jianing; Wang, Li

    2017-01-01

    Three isomorphic lanthanide metal-organic frameworks (Ln-MOFs) [LnL(H2O)2]·2H2O (Ln=Tb for 1, Eu for 2, Gd for 3) have been constructed from flexible organic ligand 4-(2-carboxyphenoxy)benzene-1,3-dioic acid (H3L). They exhibit two-dimensional (2D) layered structure with the rhombus windows along the b axis. This network can be described as a shubnikov plane net with Schäfli symbol of (43)2(46.66.83). Solid state luminescent studies indicate that 1 and 2 show the characteristic red, and green emissions of the corresponding Ln3+ ions, respectively, while 3 exhibits blue emission arising from the organic ligand. Then by adjusting the relative amounts of different luminescent components into the well-defined host framework, a series of new co-doped Ln-MOF, Tb1-xEuxL (4) (x refers to the molar ratios of Eu3+ and Tb3+), with tunable luminescence have been fabricated. The luminescent color of 4 can be tuned from green to red due to the energy transfer from the Tb3+ to Eu3+ ions by changing the doping concentration of the Eu3+ ions. In addition, 2 exhibits good stability in different solvents and excellent fluorescence sensing for small molecules, especially for CH3CN and nitrobenzene.

  11. Consideration of sub-cooled LN2 circulation system for HTS power machines

    Science.gov (United States)

    Yoshida, Shigeru; Hirai, Hirokazu; Nara, N.; Nagasaka, T.; Hirokawa, M.; Okamoto, H.; Hayashi, H.; Shiohara, Y.

    2012-06-01

    We consider a sub-cooled liquid nitrogen (LN) circulation system for HTS power equipment. The planned circulation system consists of a sub-cool heat exchanger (subcooler) and a circulation pump. The sub-cooler will be connected to a neon turbo- Brayton cycle refrigerator with a cooling power of 2 kW at 65 K. Sub-cooled LN will be delivered into the sub-cooler by the pump and cooled within it. Sub-cooled LN is adequate fluid for cooling HTS power equipment, because its dielectric strength is high and it supports a large critical current. However, a possibility of LN solidification in the sub-cooler is a considerable issue. The refrigerator will produce cold neon gas of about 60 K, which is lower than the nitrogen freezing temperature of 63 K. Therefore, we designed two-stage heat exchangers which are based on a plate-fin type and a tube-intube type. Process simulations of those heat exchangers indicate that sub-cooled LN is not frozen in either sub-cooler. The plate-fin type sub-cooler is consequently adopted for its reliability and compactness. Furthermore, we found that a cooling system with a Brayton refrigerator has the same total cooling efficiency as a cooling system with a Stirling refrigerator.

  12. Pillared-layer cluster organic frameworks constructed from nanoscale Ln10 and Cu16 clusters.

    Science.gov (United States)

    Fang, Wei-Hui; Yang, Guo-Yu

    2014-06-02

    Two pillared-layer cluster organic frameworks, [Ln5(μ3-OH)4(μ-H2O)Cu8I8L11]·H2O (L = 4-pyridin-4-yl-benzoate; Ln = Dy(1), Eu(2)), have been made by employing lanthanide oxide and copper(I) halide as the source of lanthanide and transitional metal under hydrothermal condition. Compared to the pillared-layer frameworks constructed from heterometallic layers and organic pillars, these two compounds are derived from lanthanide cluster organic layers and copper(I) halide cluster motifs. Thus, there are two distinct types of inorganic metal connectors in the structure, one is hydroxo lanthanide [Ln10(μ3-OH)8](22+) (Ln10) cluster, and the other is copper(I) halide [Cu16I16] (Cu16) cluster. The rational assembly of these two inorganic connectors and organic linear linkers leads to the formation of the two complexes here. To the best of our knowledge, they appear to be the first 3D frameworks constructed from decanuclear hydroxo lanthanide clusters. From the topological point of view, these compounds represent an intriguing example of a binodal (8,14)-connected net considering the Ln10 and Cu16 connectors as the nodes, revealing that they are typical high dimensional frameworks with high connected net based on high nuclearity nodes. Furthermore, elemental analysis, IR, TGA, PXRD, and UV-vis properties are also studied.

  13. Crystal chemistry of the orthorhombic Ln{sub 2}TiO{sub 5} compounds with Ln=La, Pr, Nd, Sm, Gd, Tb and Dy

    Energy Technology Data Exchange (ETDEWEB)

    Aughterson, Robert D., E-mail: roa@ansto.gov.au [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Lucas Heights 2234, NSW (Australia); Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney 2006, NSW (Australia); Lumpkin, Gregory R., E-mail: grl@ansto.gov.au [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Lucas Heights 2234, NSW (Australia); Thorogood, Gordon J., E-mail: gjt@ansto.gov.au [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Lucas Heights 2234, NSW (Australia); Zhang, Zhaoming [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Lucas Heights 2234, NSW (Australia); Gault, Baptiste, E-mail: baptiste.gault@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Cairney, Julie M., E-mail: julie.cairney@sydney.edu.au [Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney 2006, NSW (Australia)

    2015-07-15

    The crystal structures of seven samples of orthorhombic (Pnma) Ln{sub 2}TiO{sub 5} compounds with Ln=La, Pr, Nd, Sm, Gd, Tb and Dy were refined by Rietveld analysis of synchrotron X-ray powder diffraction (S-XRD) data. With increasing size of the lanthanide cation, the lattice parameters increase systematically: c by only ~1.5% whereas both a and b by ~6% from Dy{sub 2}TiO{sub 5} to La{sub 2}TiO{sub 5}. The mean Ti–O bond length only increases by ~1% with increasing radius of the Ln cation from Gd to La, primarily due to expansion of the pair of Ti–O{sub 3} bonds to opposite corners of the Ti–O{sub 5} square based pyramid polyhedra. For Dy{sub 2}TiO{sub 5} and Tb{sub 2}TiO{sub 5}, a significant variation in Ti–O{sub 1} and Ti–O{sub 4} bond lengths results in an increased deformation of the Ti–O{sub 5} base. The particular configuration consists of large rhombic shaped tunnels and smaller triangular tunnels along the b axis, which have implications for defect formation and migration caused by radiation damage or the ionic conductivity. - Graphical abstract: Figure: The crystallographic study of a systematic series of compounds with nominal stoichiometry Ln{sub 2}TiO{sub 5} (with Ln representing La, Pr, Nd, Sm, Gd, Tb and Dy) and orthorhombic, Pnma, symmetry shows changes in cell parameters which fit a linear trend. However, bond lengths are shown to deviate from trend with compounds containing the smaller, heavier lanthanides. - Highlights: • First fabrication and crystallographic refinement of compound Pr{sub 2}TiO{sub 5}. • First systematic study of the crystallography, using S-XRD, for Ln{sub 2}TiO{sub 5} series. • Cation to anion bonding trends and valence states are investigated. • The densities and band-gaps of the series are experimentally determined.

  14. Multifunctionality in bimetallic Ln(III)[W(V)(CN)8]3- (Ln = Gd, Nd) coordination helices: optical activity, luminescence, and magnetic coupling.

    Science.gov (United States)

    Chorazy, Szymon; Nakabayashi, Koji; Arczynski, Mirosław; Pełka, Robert; Ohkoshi, Shin-ichi; Sieklucka, Barbara

    2014-06-02

    Two chiral luminescent derivatives of pyridine bis(oxazoline) (Pybox), (SS/RR)-iPr-Pybox (2,6-bis[4-isopropyl-2-oxazolin-2-yl]pyridine) and (SRSR/RSRS)-Ind-Pybox (2,6-bis[8H-indeno[1,2-d]oxazolin-2-yl]pyridine), have been combined with lanthanide ions (Gd(3+), Nd(3+)) and octacyanotungstate(V) metalloligand to afford a remarkable series of eight bimetallic CN(-)-bridged coordination chains: {[Ln(III)(SS/RR-iPr-Pybox)(dmf)4]3[W(V)(CN)8]3}n ⋅dmf⋅4 H2O (Ln = Gd, 1-SS and 1-RR; Ln = Nd, 2-SS and 2-RR) and {[Ln(III)(SRSR/RSRS-Ind-Pybox)(dmf)4][W(V)(CN)8]}n⋅5 MeCN⋅4 MeOH (Ln = Gd, 3-SRSR and 3-RSRS; Ln = Nd, 4-SRSR and 4-RSRS). These materials display enantiopure structural helicity, which results in strong optical activity in the range 200-450 nm, as confirmed by natural circular dichroism (NCD) spectra and the corresponding UV/Vis absorption spectra. Under irradiation with UV light, the Gd(III)-W(V) chains show dominant ligand-based red phosphorescence, with λmax ≈660 nm for 1-(SS/RR) and 680 nm for 3-(SRSR/RSRS). The Nd(III)-W(V) chains, 2-(SS/RR) and 4-(SRSR/RSRS), exhibit near-infrared luminescence with sharp lines at 986, 1066, and 1340 nm derived from intra-f (4)F3/2 → (4)I9/2,11/2,13/2 transitions of the Nd(III) centers. This emission is realized through efficient ligand-to-metal energy transfer from the Pybox derivative to the lanthanide ion. Due to the presence of paramagnetic lanthanide(III) and [W(V)(CN)8](3-) moieties connected by cyanide bridges, 1-(SS/RR) and 3-(SRSR/RSRS) are ferrimagnetic spin chains originating from antiferromagnetic coupling between Gd(III) (SGd = 7/2) and W(V) (SW = 1/2) centers with J1-(SS) = -0.96(1) cm(-1), J1-(RR) =-0.95(1) cm(-1), J3-(SRSR) = -0.91(1) cm(-1), and J3-(RSRS) =-0.94(1) cm(-1). 2-(SS/RR) and 4-(SRSR/RSRS) display ferromagnetic coupling within their Nd(III)-NC-W(V) linkages.

  15. Syntheses and Characterizations of Cu-Ln Heterobinuclear Complexes with Schiff Base from 3-Formylsalicylic Acid and Ethylene Diamine

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Seven heterobinuclear complexes of Cu-Ln with N,N'-bis(3-carboxylsali cylidene) ethylenediamine(ES) were synthesized and characterized by elemental analysis, molar conductivity, thermogravimetry, IR and electronic spectra. The room tempeature magnetic moments show that there are basically no spin exchange interactions between the ions of Cu2+ and Ln3+ in the CuLnESCl·nH2O compounds.

  16. Solid-Liquid Extraction of Some Lanthanide Complexes with 1-Nitroso-2-Naphthol

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The extraction behavior of Sm(III), Eu(III) ,Er(III) and Yb(III) with 1- nitroso -2- naphthol (HA) in paraffin has been studied. The composition of extracted complexes has been determined to be LnA3 by slope analysis method. The effect of temperature on extraction system is also investigated and thermodynamic parameters are obtained.

  17. 活跃在高考中的函数f(x)=(ln x)/x

    Institute of Scientific and Technical Information of China (English)

    梅磊

    2016-01-01

    函数f(x)=ln x/x自1983年以来,已经多次出现在高考试卷中.本文就函数f(x)=ln x/x的图像和性质,及其与一组高考题的关系进行探讨,以供参考.1.函数f(x)=ln x/x的图像和性质性质1函数f(x)=ln x/x在区间(0,e)上为增函数,

  18. Two nanosized 3d-4f clusters featuring four Ln6 octahedra encapsulating a Zn4 tetrahedron.

    Science.gov (United States)

    Zheng, Xiu-Ying; Wang, Shi-Qiang; Tang, Wen; Zhuang, Gui-Lin; Kong, Xiang-Jian; Ren, Yan-Ping; Long, La-Sheng; Zheng, Lan-Sun

    2015-07-01

    Two high-nuclearity 3d-4f clusters Ln24Zn4 (Ln = Gd and Sm) featuring four Ln6 octahedra encapsulating a Zn4 tetrahedron were obtained through the self-assembly of Zn(OAc)2 and Ln(ClO4)3. Quantum Monte Carlo (QMC) simulations show the antiferromagnetic coupling between Gd(3+) ions. Studies of the magnetocaloric effect (MCE) show that the Gd24Zn4 cluster exhibits the entropy change (-ΔSm) of 31.4 J kg(-1) K(-1).

  19. Unusual osteopathy in a newborn

    Energy Technology Data Exchange (ETDEWEB)

    Jequier, S.; Nogrady, M.B.; Wesenberg, R.L.

    1983-06-01

    A newborn baby presented with hyaline membrane disease, interstitial pneumonia, jaundice, hepatosplenomegaly, and unusual bone manifestations with lytic and sclerotic bone lesions and virtually absent periosteal reaction. He subsequently developed intracranial calcifications and mental retardation. The pneumonia and hepatosplenomegaly resolved. At the time of the delivery, a sibling was suffering from a severe undetermined viral infection. The clinical evolution of the disease and the radiologic findings led us to believe that this patient has a prenatal viral infection. The laboratory tests and the histologic picture of the bone biopsy supported the diagnosis.

  20. Behaviour of LaAlO3+LnTiTaO6 (Ln= Ce, Pr or Nd) dielectric ceramic mixtures

    Indian Academy of Sciences (India)

    Sam Solomon

    2012-10-01

    The 0.1LaAlO3+0.9LnTiTaO6 (Ln= Ce, Pr or Nd) ceramics are prepared through solid state ceramic route. The structure of the materials is studied using X-ray diffraction analysis. The microstructure is analysed using scanning electron microscopy. The dielectric properties in the radio as well as in the microwave frequencies are measured and discussed. The photoluminescence of a representative sample is also analysed. The dielectric constant (r) and temperature coefficient of resonant frequency (f) are tailored without appreciable change in the quality factor. The measured values of r and f are compared with the corresponding predicted values. These mixtures can be made useful in optical and microwave communication.

  1. Facile fabrication and upconversion luminescence enhancement of LaF3:Yb3+/Ln3+@SiO2 (Ln = Er, Tm) nanostructures decorated with Ag nanoparticles.

    Science.gov (United States)

    He, Enjie; Zheng, Hairong; Dong, Jun; Gao, Wei; Han, Qingyan; Li, Junna; Hui, Le; Lu, Ying; Tian, Huani

    2014-01-31

    A novel hybrid nanostructure, that is a Ag nanoparticle decorated LaF(3):Yb(3+)/Ln(3+)@SiO(2) nanosphere (Ln=Er, Tm), was constructed by a facile strategy, and characterized by XRD, TEM, FTIR, XPS and UV-vis-NIR absorption. Obvious spectral broadening and red-shift on the surface plasmon resonance were obtained by adjusting the size and configuration of Ag nanoparticles. Effective upconversion luminescence enhancements for Er(3+) and Tm(3+) containing samples were obtained. It is suggested that the luminescence enhancement results from both the excitation and emission processes, and the configuration of the studied hybrid nanostructure is an efficient system to enhance the luminescence emission of rare earth doped nanomaterials. It is believed that the enhancement from the hybrid nanostructure will find great potential in the development of photovoltaic solar cells.

  2. Solution-combustion synthesis of Bi1–LnO1.5 (Ln = Y and La–Yb) oxide ion conductors

    Indian Academy of Sciences (India)

    Manjunath B Bellakki; A S Prakash; C Shivakumara; M S Hegde; A K Shukla

    2006-08-01

    Cubic fluorite related Bi1–LnO1.5 (Ln = Y and La–Yb) phases are synthesized by solutioncombustion method using glycine as the fuel. The cubic fluorite phase is stabilized with 25 mole% of rare earth cations. The lattice parameter of cubic phase increases linearly with size of the lanthanide ion. The synthesized powders are nano-metric in size and exhibit excellent compactability and reach 98% densification even on short period of sintering. The oxides with relatively larger cations Nd, Sm, Eu, Pr and Gd with 25 mole% composition transform to rhombohedral structure while others retain cubic upon sintering. All the phases show high oxide–ion conductivity and the values obtained are in good agreement with the reported values.

  3. High Dielectric Constant and Low-loss Dielectric Ceramics of Sr5LnTi3Ta7O30 (Ln= La, Nd, Sm and Y)

    Institute of Scientific and Technical Information of China (English)

    TU Wenmao; CHEN Pu; PENG Xiyang; LIU Ting

    2008-01-01

    Polycrystalline Sr5LnTi3Ta7O30 (Ln=La, Nd, Sm and Y) ceramics were prepared as single-phase materials through conventional solid-state ceramics method. The structure was characterized by X-ray diffraction method and scanning electron microscopy (SEM). The dielectric properties were measured from room temperature to 400 ℃. All compounds are paraelectric phases adopting the filled tetragonal tungsten bronze (TB) structure at room temperature. At 1 MHz their dielectric constant (e) varied from 109 to 139,dielectric loss changed from 0.003 3 to 0.005 8, and the temperature coefficients of the dielectric constant (τε)moved from -710 to -880×10-6 ℃-1.

  4. Nanostructured LnBaCo2O6− (Ln = Sm, Gd with layered structure for intermediate temperature solid oxide fuel cell cathodes

    Directory of Open Access Journals (Sweden)

    Augusto E. Mejía Gómez

    2017-04-01

    Full Text Available In this work, we present the combination of two characteristics that are beneficial for solid oxide fuel cell (SOFC cathodic performance in one material. We developed and evaluated for the first time nanostructured layered perovskites of formulae LnBaCo2O6-d with Ln = Sm and Gd (SBCO and GBCO, respectively as SOFC cathodes, finding promising electrochemical properties in the intermediate temperature range. We obtained those nanostructures by using porous templates to confine the chemical reagents in regions of 200-800 nm. The performance of nanostructured SBCO and GBCO cathodes was analyzed by electrochemical impedance spectroscopy technique under different operating conditions using Gd2O3-doped CeO2 as electrolyte. We found that SBCO cathodes displayed lower area-specific resistance than GBCO ones, because bulk diffusion of oxide ions is enhanced in the former. We also found that cathodes synthesized using smaller template pores exhibited better performance.

  5. Synthesis and characterization of LnAg(WO{sub 4})(MoO{sub 4})

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Martinez, F. [Universidad Politecnica de Madrid, E.U.I.T. Industrial, Ronda de Valencia 3, 28012 Madrid (Spain)], E-mail: francisco.fernandezm@upm.es; Colon, C.; Montero, J.L.; Atanes, E. [Universidad Politecnica de Madrid, E.U.I.T. Industrial, Ronda de Valencia 3, 28012 Madrid (Spain); Rivero, C. [Universidad Politecnica de Madrid, E.T.S.I. Telecomunicaciones, Avda. Complutense s/n, Ciudad Universitaria, 28040 Madrid (Spain)

    2008-02-28

    Polycrystalline LnAg(WO{sub 4})(MoO{sub 4}) powders, with Ln = La to Lu and Y, have been obtained by ceramic method. Rietveld refinement for all compounds reveals that they present tetragonal symmetry, space group I4{sub 1}/a (No. 88), where the Ln{sup 3+}/Ag{sup +} ions are located in the 4a atomic positions, since the W/Mo are randomly distributed into 4b crystal sites. In these compounds, a and b lattice parameters take values between those corresponding to tungstate and molybdate compounds. A progressive decrease in the lattice parameters is observed in going from La to Lu derivatives as a consequence of the well-known lanthanide contraction.

  6. Effect of Ln3+ on Inhibition of Tobacco RuBPcase

    Institute of Scientific and Technical Information of China (English)

    陈为钧; 陶冶; 胡天斗; 赵贵文

    2002-01-01

    The tobacco RuBPcase was purified by the method of (NH4)2SO4 precipitation and Sephadex G-200 column chromatography. The effects of Ln3+ on inhibition of RuBPcase activity were studied. The results show that the vmax (maximum velocity) of RuBPcase does not change, but its km (Michaelis constant) increases with a ki (inhibitor constant) when increasing the concentration of Ln3+ in enzymatic reaction. It indicates that the inhibitory action of Ln3+ on tobacco RuBPcase is a model of competitive inhibition with Mg2+. The ki of La3+, Ce3+ and Gd3+ is 26.3, 34.3 and 200 μmol*L-1, respectively. Their inhibitory action on the RuBPcase is in the order of La3+>Ce3+Gd3+.

  7. Investigation about thermophysical properties of Ln{sub 2}Ce{sub 2}O{sub 7} (Ln = Sm, Er and Yb) oxides for thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Hongsong, Zhang, E-mail: zhs761128@163.com [Department of Mechanical Engineering, Henan Institute of Engineering, Zhengzhou 450007 (China); Jianguo, Lv [City College, Kunming University of Science and Technology, Kunming 650050 (China); Gang, Li; Zheng, Zhang; Xinli, Wang [Department of Mechanical Engineering, Henan Institute of Engineering, Zhengzhou 450007 (China)

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ► We successfully prepared three types of new rare earth cerium oxides. ► We measured their thermophysical properties. ► These new ceramics can be explored as candidate ceramics for thermal barrier coatings. -- Abstract: Three kinds of rare earth cerium oxides – Ln{sub 2}Ce{sub 2}O{sub 7} (Ln = Sm, Er and Yb) were prepared by solid state reaction method. Their phase compositions, microstructures and thermophysical properties were investigated. Results of X-ray diffraction reveal that pure Ln{sub 2}Ce{sub 2}O{sub 7} (Ln = Sm, Er and Yb) oxides with fluorite structure are successfully synthesized in the current research. Scanning electrical microscopy results show that their microstructures are dense and no other un-reacted oxides or inter-phases exist in the interfaces between grains. Their thermal expansion coefficients are higher than those of YSZ, while their thermal conductivities are lower than those of YSZ. The decreasing ionic radius from Sm{sup 3+} to Yb{sup 3+} results in the descending thermal expansion coefficients from Sm{sub 2}Ce{sub 2}O{sub 7} to Yb{sub 2}Ce{sub 2}O{sub 7}. The effective phonon scattering by atomic weight difference contributes to the decreasing thermal conductivities from Sm{sub 2}Ce{sub 2}O{sub 7} to Yb{sub 2}Ce{sub 2}O{sub 7}. These results imply that synthesized rare earth cerium oxides have potentials to be used as novel candidate materials for thermal barrier coatings in the future.

  8. Crystal growth, transport, and the structural and magnetic properties of Ln(4)FeGa(12) with Ln = Y, Tb, Dy, Ho, and Er.

    Science.gov (United States)

    Drake, Brenton L; Grandjean, Fernande; Kangas, Michael J; Okudzeto, Edem K; Karki, Amar B; Sougrati, Moulay T; Young, David P; Long, Gary J; Chan, Julia Y

    2010-01-18

    Ln(4)FeGa(12), where Ln is Y, Tb, Dy, Ho, and Er, prepared by flux growth, crystallize with the cubic Y(4)PdGa(12) structure with the Im3m space group and with a = 8.5650(4), 8.5610(4), 8.5350(3), 8.5080(3), and 8.4760(3) A, respectively. The crystal structure consists of an iron-gallium octahedra and face-sharing rare-earth cuboctahedra of the Au(3)Cu type. Er(4)Fe(0.67)Ga(12) is iron-deficient, leading to a distortion of the octahedral and cuboctahedral environments due to the splitting of the Ga2 site into Ga2 and Ga3 sites. Further, interstitial octahedral sites that are unoccupied in Ln(4)FeGa(12) (Ln = Y, Tb, Dy, and Ho) are partially occupied by Fe2. Y(4)FeGa(12) exhibits weak itinerant ferromagnetism below 36 K. In contrast, Tb(4)FeGa(12), Dy(4)FeGa(12), Ho(4)FeGa(12), and Er(4)Fe(0.67)Ga(12) order antiferromagnetically with maxima in the molar magnetic susceptibilities at 26, 18.5, 9, and 6 K. All of the compounds exhibit metallic electric resistivity, and their iron-57 Mossbauer spectra, obtained between 4.2 and 295 K, exhibit a single-line absorption with a 4.2 K isomer shift of ca. 0.50 mm/s, a shift that is characteristic of iron in an iron-gallium intermetallic compound. A small but significant broadening in the spectral absorption line width is observed for Y(4)FeGa(12) below 40 K and results from the small hyperfine field arising from its spin-polarized itinerant electrons.

  9. The formation of the complex manganites LnSr{sub 2}Mn{sub 2}O{sub 7} (Ln = La, Nd, Gd)

    Energy Technology Data Exchange (ETDEWEB)

    Missyul, A.B., E-mail: lab2193@gmail.com [Department of Chemistry, Saint-Petersburg State University, Universitetsky pr., 26, 198504 St.-Petersburg (Russian Federation); Zvereva, I.A. [Department of Chemistry, Saint-Petersburg State University, Universitetsky pr., 26, 198504 St.-Petersburg (Russian Federation); Palstra, T.T.M. [Solid State Chemistry Laboratory, Zernike Institute for Advanced Materials, University of Groningen, 9747AG Groningen (Netherlands)

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ► Formation of the LnSr{sub 2}Mn{sub 2}O{sub 7} phases proceeds according to two different pathways. ► Cationic composition of the obtained phase depends on the formation pathway. ► Step-by-step synthesis allows obtaining single-phase material. ► Structure and magnetic properties of the single-phase NdSr{sub 2}Mn{sub 2}O{sub 7} were investigated. -- Abstract: The process of formation of the Ruddlesden–Popper phases LnSr{sub 2}Mn{sub 2}O{sub 7} (Ln = La, Nd, Gd) was investigated by means of X-ray diffraction, thermal analysis and microprobe analysis. Two parallel pathways were found for the reaction. The first one includes the formation of the intermediate K{sub 2}NiF{sub 4}-type compound by interaction of Sr{sub 7}Mn{sub 4}O{sub 15} and perovskite-type solid solution (Ln,Sr)MnO{sub 3}, while in the second one the K{sub 2}NiF{sub 4}-type intermediate is formed during the reaction of the same perovskite-type solid solution with the corresponding rare earth oxide. This result gives an explanation for the formation of two phases with slightly different cationic compositions. The kinetics of the reaction was investigated for both mechanisms resulting in determination of their relative contribution to the final composition. Pure NdSr{sub 2}Mn{sub 2}O{sub 7} was obtained using a step-by-step process according to the first mechanism, and the magnetic properties of this phase were investigated.

  10. Investigation of the structural properties of an extended series of lanthanide bis-hydroxychlorides Ln(OH)(2)Cl (Ln = Nd-Lu, except Pm and Sm).

    Science.gov (United States)

    Zehnder, Ralph A; Clark, David L; Scott, Brian L; Donohoe, Robert J; Palmer, Phillip D; Runde, Wolfgang H; Hobart, David E

    2010-06-07

    The trivalent lanthanide bis-hydroxychloride compounds, Ln(OH)(2)Cl, (Ln = Nd through Lu, with the exception of Pm and Sm) have been prepared by hydrothermal synthesis starting with LnCl(3).nH(2)O. These compounds were synthesized at temperatures not exceeding the melting point of the Teflon liners in the Parr autoclaves ( approximately 220 degrees C). The compounds obtained were characterized by single crystal X-ray diffraction analysis, diffuse reflectance, FT-IR, and FT-Raman spectroscopies. Most of the lanthanide(III) bis-hydroxychlorides are isostructural and generally crystallize in the monoclinic space group P2(1)/m. The bis-hydroxychlorides of the heavier lanthanide(III) atoms with smaller ionic radii also crystallize in the orthorhombic crystal system. Apparently hydrogen bonds between the OH groups and the Cl atoms connect the layers in the "c" direction. These H-bonds seem to be the driving force for the angle beta of the monoclinic complexes to decrease with decreasing ionic radius of the Ln(III) ion and also for tying the layers together more strongly. As a result of this behavior, the structure of the heavier 4f analogues significantly resembles that of their orthorhombic counterparts. The heavier lanthanide bis-hydroxychlorides preferentially crystallize in the orthorhombic modification. The IR absorbance and Raman frequencies of the hydroxide ligands correlate as a function of the central lanthanide(III) ionic radius. This observation is corroborated by X-ray diffraction (XRD) structural data. These compounds are quite insoluble in near-neutral and basic aqueous solutions, but soluble in acidic solutions. It is expected that the analogue actinide bis-hydroxychlorides exhibit similar behavior and that this may have important implications in the immobilization and safe disposal of nuclear waste.

  11. Syntheses and crystal structures of the bromide-derivatized lanthanoid(III) ortho-oxomolybdates(VI) LnBr[MoO{sub 4}] (Ln = Pr, Nd, Sm, Gd-Lu)

    Energy Technology Data Exchange (ETDEWEB)

    Schustereit, Tanja; Henning, Harald; Schleid, Thomas; Hartenbach, Ingo [Stuttgart Univ. (Germany). Inst. for Inorganic Chemistry

    2013-05-15

    The lanthanoid(III) bromide ortho-oxomolybdates(VI) LnBr[MoO{sub 4}] (Ln = Pr, Nd, Sm, Gd-Lu) crystallize triclinically in the space group P anti 1 (a = 686-689, b = 713-741, c = 1066-1121 pm, {alpha} = 103-106, {beta} = 107-108, {gamma} = 92-95 ) with Z = 4. The crystal structure contains two crystallographically distinguishable Ln{sup 3+} cations, each one with a coordination number of seven plus one. (Ln1){sup 3+} is surrounded by three bromide and four plus one oxide anions, while for (Ln2{sup )3+} just one bromide and six plus one oxide anions belong to the coordination sphere. Considering the smallest lanthanoids, however, the distances to the farthest anions increase so much that their contribution to the coordination spheres becomes negligible in both cases. The polyhedra around (Ln1){sup 3+} are connected to each other via common edges, which consist of two crystallographically identical Br{sup -} anions (Br1). Furthermore, the common structure of the LnBr[MoO{sub 4}] series contains two crystallographically different, discrete [MoO{sub 4}]{sup 2-} ortho-oxomolybdate(VI) tetrahedra. Two plus one oxygen atoms of each [(Mo1)O{sub 4}]{sup 2-} unit are used to interconnect the polyhedra around (Ln1){sup 3+} and (Ln2){sup 3+} together with one Br{sup -} anion (Br2). The connection between two polyhedra around (Ln2){sup 3+} is generated exclusively by two plus one oxygen atoms of two [(Mo2)O{sub 4}]{sup 2-} anions. The complete structural arrangement can be considered as a bundle of primitively packed {sub {infinity}}{sup 1}{l_brace}LnBr[MoO{sub 4}]{r_brace} chains with two alternating motifs of linkage, which are running parallel along [012]. (orig.)

  12. Crystal chemistry of the orthorhombic Ln2TiO5 compounds with Ln=La, Pr, Nd, Sm, Gd, Tb and Dy

    Science.gov (United States)

    Aughterson, Robert D.; Lumpkin, Gregory R.; Thorogood, Gordon J.; Zhang, Zhaoming; Gault, Baptiste; Cairney, Julie M.

    2015-07-01

    The crystal structures of seven samples of orthorhombic (Pnma) Ln2TiO5 compounds with Ln=La, Pr, Nd, Sm, Gd, Tb and Dy were refined by Rietveld analysis of synchrotron X-ray powder diffraction (S-XRD) data. With increasing size of the lanthanide cation, the lattice parameters increase systematically: c by only ~1.5% whereas both a and b by ~6% from Dy2TiO5 to La2TiO5. The mean Ti-O bond length only increases by ~1% with increasing radius of the Ln cation from Gd to La, primarily due to expansion of the pair of Ti-O3 bonds to opposite corners of the Ti-O5 square based pyramid polyhedra. For Dy2TiO5 and Tb2TiO5, a significant variation in Ti-O1 and Ti-O4 bond lengths results in an increased deformation of the Ti-O5 base. The particular configuration consists of large rhombic shaped tunnels and smaller triangular tunnels along the b axis, which have implications for defect formation and migration caused by radiation damage or the ionic conductivity.

  13. Catalytic combustion of soot particulates over rare-earth substituted Ln2Sn2O7 pyrochlores (Ln=La, Nd and Sm).

    Science.gov (United States)

    Wang, Zhongpeng; Zhu, Hongjian; Ai, Lijie; Liu, Xuhui; Lv, Min; Wang, Liguo; Ma, Zhenmin; Zhang, Zhaoliang

    2016-09-15

    Catalytic combustion is one of the most promising methods for diesel soot removal. Ln2Sn2O7 pyrochlores substituted with different rare-earth (RE) elements (Ln=La, Nd and Sm) were prepared through co-precipitation method for catalytic combustion of soot particulates. The structural, textural and redox properties, together with the oxygen vacancy of the catalysts were investigated systematically. Their catalytic activities were evaluated by both temperature-programmed oxidation and isothermal reaction techniques. With the increasing in RE ionic radius (r), the SnO bond strength in Ln2Sn2O7 pyrochlores evaluated from the stretching IR band was decreased, resulting in the improved reducibility and enhanced oxygen vacancies of catalysts. The increase of oxygen vacancy concentration was further confirmed by photoluminescence (PL) investigations wherein upon excitation with UV radiation, the pyrochlores nanoparticles exhibited strong and sharp transition at 408nm attributed to oxygen vacancies. Catalytic combustion and isothermal reactions revealed that the ignition activity (ignition temperature, T5) and the intrinsic activity (turnover frequency, TOF) were shown to depend correlatedly on redox properties and oxygen vacancy concentrations, both of which were influenced by the substitution of different RE elements. Among the pyrochlore oxides, the as-synthesized La2Sn2O7 sample displayed relatively the highest ignition activity and the largest intrinsic activity with TOF of 2.33×10(-3)s(-1).

  14. A two-step model for Langerhans cell migration to skin-draining LN

    OpenAIRE

    2008-01-01

    Although the role of Langerhans cells (LC) in skin immune responses is still a matter of debate, it is known that LC require the chemokine receptor CCR7 for migrating to skin-draining LN. A report in the current issue of the European Journal of Immunology unfolds some of the intricacies of LC migration, showing that LC need CXCR4, but not CCR7, for their migration from the epidermis to the dermis. Thus, LC migration to skin-draining LN occurs in two distinct phases: a first step from the epid...

  15. Infrared detector Dewars - Increased LN2 hold time and vacuum jacket life spans

    Science.gov (United States)

    Jennings, D. E.; Boyd, W. J.; Blass, W. E.

    1976-01-01

    IR detector Dewars commonly suffer from shorter than desired LN2 hold times and insulation jacket vacuum corruption over relatively short time periods. In an attempt to solve this problem for a 9144 detector Dewar, small 1 liter/s appendage ion pumps were selected for continuous pumping of the vacuum jackets. This procedure extended LN2 hold times from 20 to 60 h and virtually eliminated vacuum jacket corruption. Thus the detector systems are usable continuously over periods of 6 months or more.

  16. Validation of the CQU-DTU-LN1 series of airfoils

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Zhu, Wei Jun; Fischer, Andreas

    2014-01-01

    The CQU-DTU-LN1 series of airfoils were designed with an objective of high lift and low noise emission. In the design process, the aerodynamic performance is obtained using XFOIL while noise emission is obtained with the BPM model. In this paper we present some validations of the designed CQU......, the designed Cl and Cl/Cd agrees well with the experiment and are in general higher than those of the NACA airfoil. For the acoustic features, the noise emission of the LN118 airfoil is compared with the acoustic measurements and that of the NACA airfoil. Comparisons show that the BPM model can predict...

  17. Truncated Moments of Nonsinglet Parton Distributions in the double logarithmic $ln^2x$ approximation

    CERN Document Server

    Kotlorz, D

    2004-01-01

    The method of truncated Mellin moments in a solving QCD evolution equations of the nonsinglet structure functions $F_2^{NS}(x,Q^2)$ and $g_1^{NS}(x,Q^2)$ is presented. All calculations are performed within double logarithmic $ln^2x$ approximation. An equation for truncated moments which incorporates $ln^2x$ effects is formulated and solved for the unintegrated structure function $f^{NS}(x,Q^2)$. The contribution to the Bjorken sum rule coming from the region of very small $x$ is quantified. Further possible improvement of this approach is also discussed.

  18. Cutaneous sporotrichosis: Unusual clinical presentations

    Directory of Open Access Journals (Sweden)

    Mahajan Vikram

    2010-01-01

    Full Text Available Three unusual clinical forms of sporotrichosis described in this paper will be a primer for the clinicians for an early diagnosis and treatment, especially in its unusual presentations. Case 1, a 52-year-old man, developed sporotrichosis over pre-existing facial nodulo-ulcerative basal cell carcinoma of seven-year duration, due to its contamination perhaps from topical herbal pastes and lymphocutaneous sporotrichosis over right hand/forearm from facial lesion/herbal paste. Case 2, a 25-year-old woman, presented with disseminated systemic-cutaneous, osteoarticular and possibly pleural (effusion sporotrichosis. There was no laboratory evidence of tuberculosis and treatment with anti-tuberculosis drugs (ATT did not benefit. Both these cases were diagnosed by histopathology/culture of S. schenckii from tissue specimens. Case 3, a 20-year-old girl, had multiple intensely pruritic, nodular lesions over/around left knee of two-year duration. She was diagnosed clinically as a case of prurigo nodularis and histologically as cutaneous tuberculosis, albeit, other laboratory investigations and treatment with ATT did not support the diagnosis. All the three patients responded well to saturated solution of potassium iodide (SSKI therapy. A high clinical suspicion is important in early diagnosis and treatment to prevent chronicity and morbidity in these patients. SSKI is fairly safe and effective when itraconazole is not affordable/ available.

  19. Unusual Metastasis from Carcinoma Cervix.

    Science.gov (United States)

    Bhandari, Virendra; Kausar, Mehlam; Naik, Ayush; Batra, Manika

    2016-10-01

    Although the incidence of cancer cervix has reduced in India during the last two decades, still most of the patients presenting in tertiary care centers are in advanced stages. At this center, we see 6% of cancer cervix cases every year, and most of these cases are in stage III and IVa. All these patients have squamous cell carcinoma and were treated with a combination of external and intracavitary radiotherapy along with concurrent cisplatin given once weekly. Eighty-nine point nine % patients had achieved a complete response. Local recurrence was seen in 17.9% at a median duration of 10.5 months, and 8.17% developed distant metastasis involving lung, liver, bone, and supraclavicular lymph nodes. Three patients developed metastasis at unusual sites involving breast, paraspinal muscles, and duodenum which are very rarely involved. These patients were treated with chemotherapy using carboplatin and Paclitaxel combination but succumbed within 8-10 months of development of metastasis. The cause of involvement of these unusual sites is not clear, but it may be hematological spread, and we want to share these reports such that these sites are seen during follow-up of patients of cancer cervix.

  20. Unusual lesions of the mediastinum

    Directory of Open Access Journals (Sweden)

    Fatima Shamsuddin

    2015-01-01

    Full Text Available Objectives: To study unusual lesions in the mediastinum, which do not originate from the thymus, lymph nodes, neural tissues or germ cells, and tissues that normally engender pathologic lesions in the mediastinum. Materials and Methods: Of the 65 cases seen, 12 unusual lesion were encountered in a 5½ year period from 2006 to 2011. Results: Two cases of nodular colloid goiter and one each of the mediastinal cyst, undifferentiated carcinoma, and Langerhans cell histiocytosis (LCH affected the anterosuperior mediastinum. In the middle mediastinum, one case each of the mesothelioma, malignant gastrointestinal stromal tumor (GIST, squamous cell carcinoma (SCC, solitary fibrous tumor (SFT, and pleomorphic sarcoma (PS was seen. One case of meningeal melanocytoma (Mme and primary pleural liposarcoma (PL involved the posterior mediastinum. Persistent disease was seen in LCH after 2 years. Of all the cases with malignant lesions, only the patient with SCC was alive after 1 year. Conclusion: The cases of primary and SCC, LCH, melanocytoma, liposarcoma and PS, and GIST are unexpected and very rarely have paradigms in the mediastinum. Radiologic impression and knowledge of the compartment where these lesions arose from hardly assisted in arriving at a definitive opinion as the lesions were not typical of this location. A high index of suspicion and the immunohistochemical profile facilitated the final diagnosis.

  1. Structures and magnetic properties of rare earth double perovskites containing antimony or bismuth Ba{sub 2}LnMO{sub 6} (Ln=rare earths; M=Sb, Bi)

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, Shumpei, E-mail: m-nis-s-o@ec.hokudai.ac.jp; Hinatsu, Yukio

    2015-07-15

    A series of double perovskite-type oxides Ba{sub 2}LnMO{sub 6} (Ln=lanthanides; M=Sb, Bi) were synthesized and their structures were studied. The Ln and M are structurally ordered in the rock-salt type at the B-site of the perovskite ABO{sub 3}. For Ba{sub 2}PrBiO{sub 6} and Ba{sub 2}TbBiO{sub 6}, it has been found that the disordering between Ln ion and Bi ion occurs at the B-site of the double perovskite and both the Pr (Tb) and Bi exist in two oxidation state in the same compound from the analysis of the X-ray diffraction and magnetic susceptibility data. Magnetic susceptibility measurements show that all these compounds are paramagnetic and have no magnetic ordering down to 1.8 K. - Graphical abstract: Tolerance factor for Ba{sub 2}LnMO{sub 6} (M=Sb, Bi) plotted against the ionic radius of Ln{sup 3+}. We have found that there is a clear relation between crystal structures and tolerance factors. - Highlights: • The Ln and M ions are structurally ordered in the rock-salt type at the B-site. • The disordering between Pr (Tb) ion and Bi ion occurs at the B-site. • Ba{sub 2}LnMO{sub 6} (M=Sb, Bi) have no magnetic ordering down to 1.8 K.

  2. Ln3Pb3(IO3)13(mu3-O) (Ln = La-Nd): new types of second-order nonlinear optical materials containing two types of lone pair cations.

    Science.gov (United States)

    Hu, Ting; Qin, Li; Kong, Fang; Zhou, Yong; Mao, Jiang-Gao

    2009-03-02

    Hydrothermal reactions of lanthanide oxide, lead chloride, I(2)O(5), and H(2)O at 200 degrees C led to four novel quaternary compounds, namely, Ln(3)Pb(3)(IO(3))(13)(mu(3)-O) (Ln = La-Nd). They are isostructural, and their structures feature a complicated 3D network composed of LaO(9) and PbO(6) polyhedra interconnected by asymmetric IO(3) groups. Ln(3)Pb(3)(IO(3))(13)(mu(3)-O) (Ln = La, Pr, Nd) display moderate second harmonic generation efficiencies of about 2.0, 1.0, and 0.8 times the value of KH(2)PO(4), respectively. These compounds are thermally stable up to 520 degrees C. Luminescence measurements indicate that Ln(3)Pb(3)(IO(3))(13)(mu(3)-O) (Ln = Ce, Pr, Nd) exhibit strong emission bands in the visible or near IR region. Magnetic studies indicate that there exist significant antiferromagnetic interactions between magnetic centers in Ln(3)Pb(3)(IO(3))(13)(mu(3)-O) (Ln = Pr, Nd).

  3. Crystal structure and properties of complexes [Ln(Gly)4Im·(ClO4)4]n (Ln:Nd, Sm) constructed from eight-coordination containing square antiprism

    Science.gov (United States)

    Pan, Lu; Gao, Xiao-han; Lv, Xue-chuan; Tan, Zhi-cheng; Cao, Hui

    2016-08-01

    Two eight-coordination containing square antiprism polyhedra, [Ln(Gly)4Im·(ClO4)4]n (Ln:Nd, Sm) were synthesized through the self-assembly of Ln3+ (Ln:Nd, Sm) ions, glycine and imidazole in aqueous solution and characterized by X-ray single crystal diffraction. Both of the complexes crystallized in the C2/c space group. In the cluster, each Ln3+ ions was eight-coordination by eight oxygen atoms of the glycine. The coordination sphere of each Ln3+ ions could be described as a distorted square antiprism. Two central Ln3+ ions were connected by four bridging carboxyl groups from four glycine molecules. The Ln-O bond distances were related to the coordination geometries of the ligands. The complexes had two special solid-solid phase transitions at 224 K and 248 K, which were interpreted as a freezing-in phenomenon of the reorientational motion of perchlorate ions ClO4- and the orientational order/disorder process of ClO4- ions. The decomposition mechanism of the complexes was deduced to be three stages from 300 to 700 K. The fluorescent excitation and emission spectra showed that the complexes had strong fluorescent property.

  4. Unusual florid skeletal manifestations of primary hyperparathyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Ashebu, Samuel D.; Dahniya, Mohamed H.; Muhtaseb, Sayeed A.; Aduh, Prosper [Department of Radiology, Al-Adan Hospital (Kuwait)

    2002-12-01

    We report a case of primary hyperparathyroidism (PHPT) with advanced and unusual skeletal manifestations - a rare occurrence in developed countries nowadays. The literature is briefly reviewed. (orig.)

  5. Syntheses, Structure, Magnetism, and Optical Properties of the Interlanthanide Sulfides delta-Ln2-xLuxS3 (Ln = Ce, Pr, Nd)

    Energy Technology Data Exchange (ETDEWEB)

    Booth, Corwin H; Jin, Geng Bang; Choi, Eun Sang; Guertin, Robert P.; Brooks, James S.; Bray, Travis H.; Booth, Corwin H.; Albrecht-Schmitt, Thomas E.

    2008-01-11

    {delta}-Ln{sub 2-x}LuxS{sub 3} (Ln = Ce, Pr, Nd; x = 0.67-0.71) compounds have been synthesized through the reaction of elemental rare earth metals and S using Sb{sub 2}S{sub 3} flux at 1000 C. These compounds are isotypic with CeTmS{sub 3}, which has a complex three-dimensional structure. It includes four larger Ln{sup 3+} sites in eight- and nine-coordinate environments, two disordered seven-coordinate Ln{sup 3+}/Lu{sup 3+} positions, and two six-coordinate Lu{sup 3+} ions. The structure is constructed from one-dimensional chains of LnSn (n = 6-9) polyhedra that extend along the b axis. These polyhedra share faces or edges with two neighbors within the chains, while in the [ac] plane they share edges and corners with other chains. Least square refinements gave rise to the formulas of {delta}-Ce{sub 1.30}Lu{sub 0.70}S{sub 3}, {delta}-Pr{sub 1.29}Lu{sub 0.71}S{sub 3} and {delta}-Nd{sub 1.33}Lu{sub 0.67}S{sub 3}, which are consistent with the EDX analysis and magnetic susceptibility data. {delta}-Ln{sub 2-x}LuxS{sub 3} (Ln = Ce, Pr, Nd; x = 0.67-0.71) show no evidence of magnetic ordering down to 5 K. Optical properties measurements show that the band gaps for {delta}-Ce{sub 1.30}Lu{sub 0.70}S{sub 3}, {delta}-Pr{sub 1.29}Lu{sub 0.71}S{sub 3}, and {delta}-Nd{sub 1.33}Lu{sub 0.67}S{sub 3} are 1.25 eV, 1.38 eV, and 1.50 eV, respectively. Crystallographic data: {delta}-Ce{sub 1.30}Lu{sub 0.70}S{sub 3}, monoclinic, space group P2{sub 1}/m, a = 11.0186(7), b = 3.9796(3), c = 21.6562(15) {angstrom}, {beta} = 101.6860(10), V = 929.93(11), Z = 8; {delta}-Pr{sub 1.29}Lu{sub 0.71}S{sub 3}, monoclinic, space group P2{sub 1}/m, a = 10.9623(10), b = 3.9497(4), c = 21.5165(19) {angstrom}, {beta} = 101.579(2), V = 912.66(15), Z = 8; {delta}-Nd{sub 1.33}Lu{sub 0.67}S{sub 3}, monoclinic, space group P2{sub 1}/m, a = 10.9553(7), b = 3.9419(3), c = 21.4920(15) {angstrom}, {beta} = 101.5080(10), V = 909.47(11), Z = 8.

  6. Dissociation of diglycolamide complexes of Ln3+ (Ln = La-Lu) and An3+ (An = Pu, Am, Cm): redox chemistry of 4f and 5f elements in the gas phase parallels solution behavior.

    Science.gov (United States)

    Gong, Yu; Tian, Guoxin; Rao, Linfeng; Gibson, John K

    2014-11-17

    Tripositive lanthanide and actinide ions, Ln(3+) (Ln = La-Lu) and An(3+) (An = Pu, Am, Cm), were transferred from solution to gas by electrospray ionization as Ln(L)3(3+) and An(L)3(3+) complexes, where L = tetramethyl-3-oxa-glutaramide (TMOGA). The fragmentation chemistry of the complexes was examined by collision-induced and electron transfer dissociation (CID and ETD). Protonated TMOGA, HL(+), and Ln(L)(L-H)(2+) are the major products upon CID of La(L)3(3+), Ce(L)3(3+), and Pr(L)3(3+), while Ln(L)2(3+) is increasingly pronounced beyond Pr. A C-Oether bond cleavage product appears upon CID of all Ln(L)3(3+); only for Eu(L)3(3+) is the divalent complex, Eu(L)2(2+), dominant. The CID patterns of Pu(L)3(3+), Am(L)3(3+), and Cm(L)3(3+) are similar to those of the Ln(L)3(3+) for the late Ln. A striking exception is the appearance of Pu(IV) products upon CID of Pu(L)3(3+), in accord with the relatively low Pu(IV)/Pu(III) reduction potential in solution. Minor divalent Ln(L)2(2+) and An(L)2(2+) were produced for all Ln and An; with the exception of Eu(L)2(2+) these complexes form adducts with O2, presumably producing superoxides in which the trivalent oxidation state is recovered. ETD of Ln(L)3(3+) and An(L)3(3+) reveals behavior which parallels that of the Ln(3+) and An(3+) ions in solution. A C-Oether bond cleavage product, in which the trivalent oxidation state is preserved, appeared for all complexes; charge reduction products, Ln(L)2(2+) and Ln(L)3(2+), appear only for Sm, Eu, and Yb, which have stable divalent oxidation states. Both CID and ETD reveal chemistry that reflects the condensed-phase redox behavior of the 4f and 5f elements.

  7. Phase transformations during HLnTiO{sub 4} (Ln=La, Nd) thermolysis and photocatalytic activity of obtained compounds

    Energy Technology Data Exchange (ETDEWEB)

    Silyukov, Oleg I., E-mail: olegsilyukov@yandex.ru; Abdulaeva, Liliia D.; Burovikhina, Alena A.; Rodionov, Ivan A.; Zvereva, Irina A.

    2015-03-15

    Layered HLnTiO{sub 4} (Ln=La, Nd) compounds belonging to Ruddlesden–Popper phases were found to form partially hydrated compounds Ln{sub 2}Ti{sub 2}O{sub 7}·xH{sub 2}O during thermal dehydration as well as defect oxides Ln{sub 2}□Ti{sub 2}O{sub 7} as final products. Further heating of metastable defect Ln{sub 2}□Ti{sub 2}O{sub 7} substances leads to the formation of pyrochlore-type oxides Ln{sub 2}Ti{sub 2}O{sub 7} {sub (p)}, with subsequent transformation under higher temperatures to stable layered 110-type perovskites Ln{sub 2}Ti{sub 2}O{sub 7}. The occurring structure transformations lead to an increase of photocatalytic activity in the order of HLnTiO{sub 4}<Ln{sub 2}Ti{sub 2}O{sub 7}·yH{sub 2}O<Ln{sub 2}□Ti{sub 2}O{sub 7}<Ln{sub 2}Ti{sub 2}O{sub 7} {sub (p)}<Ln{sub 2}Ti{sub 2}O{sub 7} in the reaction of hydrogen evolution from aqueous isopropanol solution. - Graphical abstract: Layered HLnTiO{sub 4} (Ln=La, Nd) compounds form partially hydrated Ln{sub 2}Ti{sub 2}O{sub 7}·xH{sub 2}O compounds during thermal dehydration, further heating results to the formation to defect oxides Ln{sub 2}□Ti{sub 2}O{sub 7}, pyrochlor-type oxides Ln{sub 2}Ti{sub 2}O{sub 7} {sub (p)}, with subsequent transformation to layered 110-type perovskites Ln{sub 2}Ti{sub 2}O{sub 7}. Structure transformations lead to an increase of photocatalytic activity in the order of HLnTiO{sub 4}<Ln{sub 2}Ti{sub 2}O{sub 7}·yH{sub 2}O<Ln{sub 2}□Ti{sub 2}O{sub 7}<Ln{sub 2}Ti{sub 2}O{sub 7} {sub (p)}<Ln{sub 2}Ti{sub 2}O{sub 7}. - Highlights: • We studied dehydration and further thermolysis of HLnTiO{sub 4} (Ln=La, Nd) compounds. • XRD, STA and solid state IR studies were carried out. • A new series of metastable Ln{sub 2}Ti{sub 2}O{sub 7}·yH{sub 2}O compounds was obtained. • We examined the photocatalytic activity of all obtained compounds. The hydrogen evolution rate increased in the course of the structure changes during thermolysis.

  8. Unusual clinical manifestations of leptospirosis

    Directory of Open Access Journals (Sweden)

    Bal A

    2005-01-01

    Full Text Available Leptospirosis has protean clinical manifestations. The classical presentation of the disease is an acute biphasic febrile illness with or without jaundice. Unusual clinical manifestations may result from involvement of pulmonary, cardiovascular, neural, gastrointestinal, ocular and other systems. Immunological phenomena secondary to antigenic mimicry may also be an important component of many clinical features and may be responsible for reactive arthritis. Leptospirosis in early pregnancy may lead to fetal loss. There are a few reports of leptospirosis in HIV- infected individuals but no generalisation can be made due to paucity of data. It is important to bear in mind that leptospiral illness may be a significant component in cases of dual infections or in simultaneous infections with more than two pathogens.

  9. Unusual Cause of Knee Locking

    Directory of Open Access Journals (Sweden)

    Gazi Huri

    2013-01-01

    Full Text Available We report a case of partial intrasubstance tear of popliteus tendon as an unusual cause of pseudolocking of the knee. A 13-year-old semiprofessional soccer player applied to our clinic with a locked right knee in spite of the therapy applied (cold pack, NSAID, and immobilization in another institution 20 days after the injury. Significant extension loss was observed in his right knee with 30∘–90∘ ROM. Magnetic resonance imaging (MRI and arthroscopy confirmed the intrasubstance tear of popliteus tendon and synovitis. The ruptured part of the tendon was debrided, and the inflammatory tissue around the tendon, which may lead to pseudolocking, was gently removed with a shaver in order to regain the normal ROM. The patient was discharged with full ROM and weight bearing first day after the surgery. To our knowledge, this is the first case demonstrating intrasubstance tear of popliteus tendon causing pseudolocking of the knee.

  10. Vaginal haemangioendothelioma: an unusual tumour.

    LENUS (Irish Health Repository)

    Mohan, H

    2012-02-01

    Vaginal tumours are uncommon and this is a particularly rare case of a vaginal haemangioendothelioma in a 38-year-old woman. Initial presentation consisted of symptoms similar to uterovaginal prolapse with "something coming down". Examination under anaesthesia demonstrated a necrotic anterior vaginal wall tumour. Histology of the lesion revealed a haemangioendothelioma which had some features of haemangiopericytoma. While the natural history of vaginal haemangioendothelioma is uncertain, as a group, they have a propensity for local recurrence. To our knowledge this is the third reported case of a vaginal haemangioendothelioma. Management of this tumour is challenging given the paucity of literature on this tumour. There is a need to add rare tumours to our "knowledge bank" to guide management of these unusual tumours.

  11. Unusual tumours of the lung.

    Science.gov (United States)

    Wright, E S; Pike, E; Couves, C M

    1983-09-01

    Unusual lung tumors are not simply pathological curiosities. They demonstrate features of major significance in diagnosis, treatment, and prognosis. Six of these tumours are discussed: (1) Carcinosarcoma is rarely found in the lung. The histogenis of the lesion is unclear and the prognosis is poor. (2) Only three cases of pleomorphic adenoma have previously been described. Differentiation from other "mixed tumours" of the lung is essential. (3) A rare case of bronchial adenoma producing ectopic ACTH is described. Early recognition of these polypeptide hormone-secreting tumours is stressed. (4) Oat cell carcinoma with the myasthenic (Eaton-Lambert) syndrome shows the clinical features which should permit early tumour diagnosis. The hazards of muscle relaxants must be recognized. (5) Prostatic carcinoma with endobronchial metastases is is discussed. The importance of localization of the primary tumour is emphasized. (6) An example of double primary carcinoma is presented. The rarity of this finding may be related to the poor prognosis of patients with bronchogenesis carcinoma.

  12. Unusual presentation of metastatic adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Mudan Satvinder

    2007-10-01

    Full Text Available Abstract Background The most common tumours of the adrenal gland are adenoma, pheochromocytoma, adrenocortical carcinoma, and metastases. Although the imaging features of these tumours are established, the imaging characteristics of uncommon adrenal masses are less well known. In patients with extradrenal tumour, incidental discovery of an adrenal mass necessitates excluding the possibility of metastatic malignancy. Case presentation A 52 year-old female was diagnosed with oesophageal adenocarcinoma and treated with oesophagectomy and adjuvant chemotherapy. Sixteen months later on staging CT scan a 2 × 2 cm adrenal mass was detected, which increased in size over a period of time to 3 × 3 cm in size. Adrenalectomy was performed and histological examination revealed metastatic adenocarcinoma within an adrenal adenoma. Conclusion The present case highlights the unusual behaviour of an oesophageal adenocarcinoma causing metastasis to an adrenocortical adenoma.

  13. Anion dependent self-assembly of 56-metal Cd-Ln nanoclusters with enhanced near-infrared luminescence properties

    Science.gov (United States)

    Yang, Xiaoping; Schipper, Desmond; Zhang, Lijie; Yang, Keqin; Huang, Shaoming; Jiang, Jijun; Su, Chengyong; Jones, Richard A.

    2014-08-01

    Two series of Cd-Ln clusters: nano-drum [Ln8Cd24L12(OAc)48] and nano-double-drum [Ln12Cd44L20Cl30(OAc)54] (Ln = Nd and Yb) were prepared using a flexible Schiff base ligand bearing two aryl-Br groups. Chloride (Cl-) ions, together with the interactions of Br with other electronegative atoms, play a key role in the formation of the nano-double-drums. The structures were studied by TEM and photophysical properties were determined.Two series of Cd-Ln clusters: nano-drum [Ln8Cd24L12(OAc)48] and nano-double-drum [Ln12Cd44L20Cl30(OAc)54] (Ln = Nd and Yb) were prepared using a flexible Schiff base ligand bearing two aryl-Br groups. Chloride (Cl-) ions, together with the interactions of Br with other electronegative atoms, play a key role in the formation of the nano-double-drums. The structures were studied by TEM and photophysical properties were determined. Electronic supplementary information (ESI) available: Full experimental and characterization details for 1-4. CCDC 972369-972372. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4nr03075c

  14. Positive Integer Solutions of the Diophantine Equation $x^2 - L_n xy + (-1)^n y^2 = ± 5^r$

    Indian Academy of Sciences (India)

    Refik Keskin; Zafer Şiar

    2014-08-01

    In this paper, we consider the equation $x^2-L_n xy+(-1)^n y^2=± 5^r$ and determine the values of for which the equation has positive integer solutions and . Moreover, we give all positive integer solutions of the equation $x^2-L_n xy+(-1)^n y^2=± 5^r$ when the equation has positive integer solutions.

  15. Transitory and steady analysis of grounding structures using the LN-FDTD method

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Rodrigo Melo e Silva de; Souza Sobrinho, Carlos Leonidas da S. [Federal University of Para (UFPA), Belem, PA (Brazil). Electrical and Computer Engineering Dept.], Emails: rodrigo@lane.ufpa.br, leonidas@ufpa.br

    2007-07-01

    This work presents an overview of the LN-FDTD method (FDTD in local and non orthogonal coordinate system) to solve Maxwell's Equations. This method has been used to simulate curved grounding structures. Results are obtained by employing the presented methodology and they are compared to reference equations available in literature. (author)

  16. Orthopositronium lifetime. Analytic results in O ({alpha}) and O ({alpha}{sup 3} ln {alpha})

    Energy Technology Data Exchange (ETDEWEB)

    Kniehl, B.A.; Kotikov, A.V.; Veretin, O.L. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2008-06-15

    We present the O({alpha}) and O({alpha}{sup 3}ln {alpha}) corrections to the total decay width of orthopositronium in closed analytic form, in terms of basic transcendental numbers, which can be evaluated numerically to arbitrary precision. (orig.)

  17. Microstructure Evolution of Multi-Heat Forging and Numerical Simulation for 316LN Steel

    Directory of Open Access Journals (Sweden)

    Duan Xing-Wang

    2014-02-01

    Full Text Available Microstructure evolution has been studied by multi-heat forging experiments and numerical simulation in order to determine the reasonable forging technology of 316 LN steel. The microstructure evolution models were obtained by hot compressive tests and heat treatment tests of 316 LN steels. The one-heat and three-heat upsetting experiments were carried on. Meanwhile, the corresponding numerical simulations were performed. The results show that, the grain uniformity of three-heat upsetting is much better that of one-heat upsetting. The average grain size of three-heat upsetting is smaller than that of one-heat upsetting. So, the forging technology of multi-heat and little deformation should be adopted for 316 LN steel forging. By comparing experimental average grain sizes with simulated average grain sizes for three-heat upsetting, it is found that the simulated values are in agreement with experimental values, which shows that the numerical simulation can be employed to predict the forging microstructure evolution of 316 LN steel.

  18. Ball Indentation Studies on the Effect of Nitrogen on the Tensile Properties of 316LN SS

    Science.gov (United States)

    Mathew, M. D.; Ganesh Kumar, J.; Ganesan, V.; Laha, K.

    2015-12-01

    Type 316L(N) stainless steel (SS) containing 0.02-0.03 wt% carbon and 0.06-0.08 wt% nitrogen is used as the major structural material for the components of fast reactors. Research is underway to improve the high-temperature mechanical properties of 316LN SS by increasing the nitrogen content in the steel above the level of 0.08 wt%. In this investigation, ball indentation (BI) technique was used to evaluate the effect of nitrogen content on the tensile properties of 316LN SS. BI tests were conducted on four different heats of 316LN SS containing 0.07, 0.11, 0.14 and 0.22 wt% nitrogen in the temperature range 300-923 K. The tensile properties such as yield strength and ultimate tensile strength increased with increase in nitrogen content at all the investigated temperatures. These results were consistent with the corresponding uniaxial tensile test results. These studies showed that BI technique can be used to optimize the chemical composition during alloy development by evaluating tensile properties with minimum volume of material.

  19. Nanomaterial size distribution analysis via liquid nebulization coupled with ion mobility spectrometry (LN-IMS).

    Science.gov (United States)

    Jeon, Seongho; Oberreit, Derek R; Van Schooneveld, Gary; Hogan, Christopher J

    2016-02-21

    We apply liquid nebulization (LN) in series with ion mobility spectrometry (IMS, using a differential mobility analyzer coupled to a condensation particle counter) to measure the size distribution functions (the number concentration per unit log diameter) of gold nanospheres in the 5-30 nm range, 70 nm × 11.7 nm gold nanorods, and albumin proteins originally in aqueous suspensions. In prior studies, IMS measurements have only been carried out for colloidal nanoparticles in this size range using electrosprays for aerosolization, as traditional nebulizers produce supermicrometer droplets which leave residue particles from non-volatile species. Residue particles mask the size distribution of the particles of interest. Uniquely, the LN employed in this study uses both online dilution (with dilution factors of up to 10(4)) with ultra-high purity water and a ball-impactor to remove droplets larger than 500 nm in diameter. This combination enables hydrosol-to-aerosol conversion preserving the size and morphology of particles, and also enables higher non-volatile residue tolerance than electrospray based aerosolization. Through LN-IMS measurements we show that the size distribution functions of narrowly distributed but similarly sized particles can be distinguished from one another, which is not possible with Nanoparticle Tracking Analysis in the sub-30 nm size range. Through comparison to electron microscopy measurements, we find that the size distribution functions inferred via LN-IMS measurements correspond to the particle sizes coated by surfactants, i.e. as they persist in colloidal suspensions. Finally, we show that the gas phase particle concentrations inferred from IMS size distribution functions are functions of only of the liquid phase particle concentration, and are independent of particle size, shape, and chemical composition. Therefore LN-IMS enables characterization of the size, yield, and polydispersity of sub-30 nm particles.

  20. Unusual Fears in Children with Autism

    Science.gov (United States)

    Mayes, Susan Dickerson; Calhoun, Susan L.; Aggarwal, Richa; Baker, Courtney; Mathapati, Santosh; Molitoris, Sarah; Mayes, Rebecca D.

    2013-01-01

    Unusual fears have long been recognized as common in autism, but little research exists. In our sample of 1033 children with autism, unusual fears were reported by parents of 421 (41%) of the children, representing 92 different fears. Many additional children had common childhood fears (e.g., dogs, bugs, and the dark). More than half of children…

  1. Unusual manifestations of secondary urothelial carcinoma

    Directory of Open Access Journals (Sweden)

    Chaohui Lisa Zhao

    2016-03-01

    Full Text Available High-grade papillary urothelial carcinoma regularly invades the bladder wall, adjacent prostate, seminal vesicles, ureters, vagina, rectum, retroperitoneum, and regional lymph nodes. In advanced stages, it may disseminate to the liver, lungs, and bone marrow. On rare occasions, unusual metastatic foci like skin have been reported. The incidence of urothelial carcinoma has increased with associated rise in variants of urothelial carcinoma and unusual metastatic foci. It is imperative that urologists and pathologists are aware of the unusual variants and unusual metastatic locations to expedite the diagnostic process. Hereby we report an unusual case of secondary involvement of spinal nerve by conventional urothelial carcinoma. Also a second case of rhabdoid variant of urothelial carcinoma showing synchronous involvement of bladder and subcutaneous tissue of upper extremity is presented.

  2. Synthesis and Characterization of [(C5H4SiMe2tBu)2Ln((-SnBu)]2 (Ln = Y, Er)1

    Institute of Scientific and Technical Information of China (English)

    LI Yan-Rong; ZHANG Zheng-Xing; CHEN Zhen-Xia; LIU Rui-Ting; ZHOU Xi-Geng

    2008-01-01

    (C5H4SiMe2tBu)2LnnBu reacted with 1 equiv. of elemental sulfur in toluene at ambient temperature to yield the corresponding lanthanocene thiolates [(C5H4SiMe2tBu)2Ln(m-SnBu)]2 (Ln = Y (1), Er (2)). Complexes 1 and 2 have been characterized by elemental analysis, IR, mass spectros- copy and X-ray single-crystal diffraction analysis. Both complexes are of monoclinic with space group P21/c, formula C52H94S2Si4Y2 1 (C52H94S2Si4Er2 2) Mr = 1073.57 (1230.27), a = 8.495(2) (8.41(2)), b = 26.913(8) (26.67(7)), c = 13.756(4) (13.68(4)) (A), α = 90(90), β = 101.184(5) (101.57(4)), γ = 90 (90)°, V = 3085.1(15) (3007(14))(A)3, Dc = 1.156 (1.359) g·cm-3, Z = 2 (2), F(000) = 1144 (1260), μ = 2.046 (2.951) cm-1, R = 0.0687 (0.0749) and wR = 0.1306 (0.1507) for observed reflections with I > 2σ(I). X-ray structures of 1 and 2 definitively prove that only one sulfur atom is inserted into the Ln-C(nBu) bond, forming a thiolate ligand.

  3. Electrochemical and spectroscopic investigation of Ln3+ (Ln = Sm, Eu, and Yb) solvation in bis(trifluoromethylsulfonyl)imide-based ionic liquids and coordination by N,N,N',N'-tetraoctyl-3-oxa-pentane diamide (TODGA) and chloride.

    Science.gov (United States)

    Pan, Yunfeng; Hussey, Charles L

    2013-03-18

    The electrochemistry and electronic absorption spectroscopy of samarium, europium, and ytterbium were investigated in the 1-(1-butyl)trimethylammonium bis(trifluoromethylsulfonyl)imide (BuMe3NTf2N) and 1-butyl-3-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (BuMePyroTf2N) ionic liquids and in these solvents containing the neutral tridentate ligand N,N,N',N'-tetraoctyl-3-oxo-pentane diamide (TODGA) and the anionic hard ligand chloride. Lanthanide ions were introduced into the ionic liquids by controlled potential oxidation of the respective metals to yield solutions containing Eu(2+), Sm(3+), and Yb(3+), and it was possible to cycle between Eu(2+) and Eu(3+) as well as Yb(3+) and Yb(2+) using controlled potential electrolysis. Electronic absorption spectroscopy suggested that the Ln(3+) species are weakly solvated by Tf2N(-) anions as [Ln(Tf2N)x]((x-3)-) in the neat ILs. The quasireversible Ln(3+/2+) couples of all three elements were readily accessible in these ILs, but Sm(2+) was only stable on the voltammetric time scale. Addition of TODGA to [Ln(Tf2N)x]((x-3)-) solutions produces 3:1 complexes with Eu(3+) and Sm(3+) but only a 2:1 complex with the smaller Yb(3+) ion. Depending on the temperature, addition of Cl(-) to solutions of [Ln(Tf2N)x]((x-3)-) induces precipitation of LnCl3(s) when the mole ratio mCl(-)/mLn(3+) ≈ 3. However, when mCl(-)/mLn(3+) > 3, these precipitates redissolve to form the octahedral chloride complexes, [LnCl6](3-).

  4. Hydrothermal synthesis, structure, and optical properties of two nanosized Ln26 @CO3 (Ln=Dy and Tb) cluster-based lanthanide-transition-metal-organic frameworks (Ln MOFs).

    Science.gov (United States)

    Zhang, Yu; Huang, Lian; Miao, Hao; Wan, Hong Xiang; Mei, Hua; Liu, Ying; Xu, Yan

    2015-02-16

    Two Ln26 @CO3 (Ln=Dy and Tb) cluster-based lanthanide-transition-metal-organic frameworks (Ln MOFs) formulated as [Dy26 Cu3 (Nic)24 (CH3 COO)8 (CO3 )11 (OH)26 (H2 O)14 ]Cl ⋅3 H2 O (1; HNic=nicotinic acid) and [Tb26 NaAg3 (Nic)27 (CH3 COO)6 (CO3 )11 (OH)26 Cl(H2 O)15 ]⋅7.5 H2 O (2) have been successfully synthesized by hydrothermal methods and characterized by IR, thermogravimetric analysis (TGA), elemental analysis, and single X-ray diffraction. Compound 1 crystallizes in the monoclinic space group Cc with a=35.775(12) Å, b=33.346(11) Å, c=24.424(8) Å, β=93.993(5)°, V=29065(16) Å(3) , whereas 2 crystallizes in the triclinic space group P$\\bar 1$ with a=20.4929(19) Å, b=24.671(2) Å, c=29.727(3) Å, α=81.9990(10)°, β=88.0830(10)°, γ=89.9940(10)°, V=14875(2) Å(3) . Structural analysis indicates the framework of 1 is a 3D perovskite-like structure constructed out of CO3 @Dy26 building units and Cu(+) centers by means of nicotinic acid ligand bridging. In 2, however, nanosized CO3 @Tb26 units and [Ag3 Cl](2+) centers are connected by Nic(-) bridges to give rise to a 2D structure. It is worth mentioning that this kind of 4d-4f cluster-based MOF is quite rare as most of the reported analogous compounds are 3d-4f ones. Additionally, the solid-state emission spectra of pure compound 2 at room temperature suggest an efficient energy transfer from the ligand Nic(-) to Tb(3+) ions, which we called the "antenna effect". Compound 2 shows a good two-photon absorption (TPA) with a TPA coefficient of 0.06947 cm GM(-1) (1 GM=10(-50)  cm(4)  s photon(-1) ), which indicates that compound 2 might be a good choice for third-order nonlinear optical materials.

  5. Crystal Structure and Luminescence of the Orthoborate Ln1-xBO3:Eux(Ln=Y,Gd)%稀土正硼酸盐Ln{1-xBO3:Eux(Ln=Y,Gd)的结构与发光特性

    Institute of Scientific and Technical Information of China (English)

    张巍巍; 谢平波; 张慰萍; 尹民; 荆隆; 吕少哲; 楼立人; 夏上达

    2001-01-01

    LnBO3:Eu(Ln=Y,Gd)orthoborates were prepared by solid state reaction and sol-gel technique. Nephelauxetic effect was observed in the 7F0?5D0 transition of Eu3+ in a pseudo-vaterite type YBO3 when the excitation spectra were carried out at different temperatures. According to the luminescence of YBO3:Eu at low temperatures and the effect of different temperatures on the luminescence, the site symmetries of Ln3+ in YBO3 were revised to be a D3 and a similar C3. Different luminescent intensities and quenching concentrations were found for the sol-gel samples and corresponding solid-state-synthesized ones. The effect of defects or dislocations was taken into account to explain these phenomena. The luminescence of annealed samples and the Raman spectra of them suggested the presence of Eu3+ clusters in the sol-gel crystalline YBO3:Eu.%用溶胶-凝胶法和高温固相反应分别制备了纳米量级和常规尺度的稀土正硼酸盐荧光粉LnBO3:Eu(Ln=Y,Gd),测量了它们的激发光谱并首次观察到了YBO3:Eu中Eu3+的7F05D0跃迁的Nephelauxetic效应. 根据低温下的激发光谱,发射光谱以及变温条件对发光光谱的影响, YBO3中Ln3+所占据的两种格位的对称性被修正为C3?和D3. 在不同方法制备的样品中观察到了不同的发光强度和猝灭浓度. 缺陷?的影响是产生这种不同的原因. 退火样品的发光和拉曼散射谱的变化反映出掺杂的杂质Eu3+的团聚化是可能的缺陷来源.

  6. Synthesis of rare earth metal-organic frameworks (Ln-MOFs) and their properties of adsorption desulfurization

    Institute of Scientific and Technical Information of China (English)

    刘想; 王景艳; 李庆远; 蒋赛; 张天浩; 季生福

    2014-01-01

    The rare earth metal-organic frameworks (Ln-MOFs) materials, Ln(BTC)(H2O)·(DMF), were synthesized using the rare earth metal (Ln=Sm, Eu, Tb, Y) and 1,3,5-trimesic acid (BTC) as a metal ion center and ligand, respectively. X-ray diffraction (XRD) and infrared spectroscopy (FT-IR) were employed to characterize the Ln-MOFs structural features. The property of adsorption desul-furization of Ln-MOFs materials was evaluated with thiophene/n-octane as model oil. The results showed that Ln-MOFs with rare earth metals Sm, Eu, Tb and Y had perfect crystalline and good adsorption desulfurization ability. Y(BTC)(H2O)·(DMF) material had a comparatively better activity for the adsorption desulfurization with desulfurization rate up to 80.7%and the sulfur adsorption ca-pacity was found 30.7 mgS/g(Y-MOFs). The Ln-MOFs materials had excellent reusability.

  7. Optical characterization and the energy level scheme for NaYP{sub 2}O{sub 7}:Ln{sup 3+} (Ln=Ce, Sm, Eu, Tb, Yb)

    Energy Technology Data Exchange (ETDEWEB)

    Novais, S.M.V., E-mail: suellenvaleriano@yahoo.com.br [Laboratory of Advanced Ceramic Materials, Physics Department, Federal University of Sergipe, 49.100-000, São Cristóvão, SE (Brazil); Dobrowolska, A.; Bos, A.J.J.; Dorenbos, P. [Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands); Macedo, Z.S. [Laboratory of Advanced Ceramic Materials, Physics Department, Federal University of Sergipe, 49.100-000, São Cristóvão, SE (Brazil)

    2014-04-15

    Vacuum ultra-violet spectroscopy at low temperature was performed with undoped and Ln{sup 3+}-doped NaYP{sub 2}O{sub 7} (Ln=Ce, Sm, Eu, Tb and Yb). The emission observed from the NaYP{sub 2}O{sub 7} host was attributed to self-trapped exciton (STE) recombination. Dopant ions were well incorporated and responsible for characteristic luminescent emission in the doped samples. From excitation curves, 4f–5d transitions were identified for Ce{sup 3+}, Sm{sup 3+} and Tb{sup 3+} and charge transfer processes were noticed for Eu{sup 3+}, Sm{sup 3+} and Yb{sup 3+}. The experimental data obtained was used to determine the positions of the energy levels of divalent and trivalent lanthanides relative to the valence and conduction band of this compound. The experimentally derived levels are in good agreement with model predictions. The results are valuable to provide a better understanding on the performance of NaYP{sub 2}O{sub 7} and related diphosphates as luminescent materials. -- Highlights: • NaYP{sub 2}O{sub 7} polycrystalline samples were produced via the sol–gel method. • VUV excitation and emission spectra were successfully studied. • Luminescent properties were discussed. • The experimentally derived energy levels are in good agreement with model predictions.

  8. Preparation and characterization of new mixed sandwiched layered compounds Ln/sub 32/Nb/sub 28/S/sub 88/ (Ln = La, Ce)

    Energy Technology Data Exchange (ETDEWEB)

    Meerschaut, A.; Rabu, P.; Rouxel, J.

    1989-01-01

    New ternary Ln/sub 32/Nb/sub 28/S/sub 88/ (Ln = La, Ce) compounds have been obtained. They crystallize in the orthorhombic space group (Ccca) with a = 23.031(9) /angstrom/, b = 23.216(6) /angstrom/, c = 5.806(2) /angstrom/, and a = 22.877(9) /angstrom/, b = 23.127(13) /angstrom/, c = 5.775(2) /angstrom/ for La/sub 32/Nb/sub 28/S/sub 88/ and Ce/sub 32/Nb/sub 28/S/sub 88/, respectively. The structure of La/sub 32/Nb/sub 28/S/sub 88/ (Z = 1) has been refined until R = 0.155 for 639 reflections with I />=/ 4sigmaI and 56 variables. The structure may be described as a mixed sandwiched layered type where /absolute value/NbS/sub 2/ and /absolute value/LaS slabs alternate. These new compounds may be classified as misfit layer compounds.

  9. Structure of trihydrated rare-earth acid diphosphates LnHP 2O 7·3H 2O ( Ln=La, Er)

    Science.gov (United States)

    Ben Moussa, S.; Ventemillas, S.; Cabeza, A.; Gutierrez-Puebla, E.; Sanz, J.

    2004-06-01

    In trihydrated lanthanum acid-diphosphates LnHP 2O 7·3H 2O, prepared from acid LnCl 3 and Na 4P 2O 7 solutions (pH=1), two crystal forms were obtained. Layered structures of two representative members of this family have been determined by single-crystal X-ray diffraction (XRD) technique. In the case of orthorhombic LaHP 2O 7·3H 2O (type I), lanthanum cations are ninefold coordinated and diphosphate groups adopt a staggered (alternated) configuration. In the case of triclinic ErHP 2O 7·3H 2O (type II), erbium cations are eightfold coordinated and diphosphate groups adopt an eclipsed configuration. In agreement with Infrared (IR) spectroscopic data, a bended configuration for diphosphate groups has been deduced. In both structures, one-dimensional chains of edge-sharing rare-earth polyhedra are linked together by diphosphate groups to form the phosphate layers. In both diphosphates, PO 4 and HPO 4 environments have been identified by 31P MAS-NMR technique. In the two compounds, OH groups of HPO 4 tetrahedra point out of diphosphate planes interacting with adjacent layers. In La-diphosphate, the interaction between HPO 4 groups and water molecules of adjacent layers is favored; however, in Er-diphosphate, the interaction between phosphate acid groups of contiguous layers is produced. Based on structural information deduced, differences detected in IR and NMR spectra of two disphosphates are discussed.

  10. Combinative energy,oxygen deficiency and superconductivity in LnBa2Cu3O7-x (Ln=Nd,Er,Sm)

    Institute of Scientific and Technical Information of China (English)

    王淑霞; 刘文利; 韩圣浩; 张酣

    2003-01-01

    The correlation among the combinative energy, superconductivity, oxygen content, the position of holes in different planes, and the position of holes in the Cu(2)-O plane in LnBa2Cu3O7-x (Ln= Nd, Er, and Sm) has been investigated on the basis of a block model. The results indicate that the combinative energy decreases with increasing Tc in all of these compounds. And also, the combinative energies are obviously different with holes at different positions in the Cu(2)-O plane when the oxygen deficiency is low. However, this difference becomes less with increasing the oxygen deficiency.The effect of the holes in different positions on the combinative energy supplies some clue to the understanding of an unresolved problem, i.e. whether the distribution of carriers in the CuO2 plane is uniform or inhomogeneous. The results not only show that the structural characters, the combinative energy between two structural blocks and the superconductivity are closely interrelated in this class of compounds, but also reveal some differences among these systems. The relationship between the combinative energy and the Tc value in NdBa2Cu3O7-x shows some features different from the systems containing Er or Sm.

  11. Synthesis and structure of Ln sub 2 Ta sub 3 Se sub 2 O sub 8 (Ln = La, Ce, Pr, Nd)

    Energy Technology Data Exchange (ETDEWEB)

    Brennan, T.; Aleandri, L.; Ibers, J. (Northwestern Univ., Evanston, IL (USA))

    1991-04-01

    A series of compounds Ln{sub 2}Ta{sub 3}Se{sub 2}O{sub 8}(Ln = La, Ce, Pr, Nd) has been prepared and characterized. Pr{sub 2}Ta{sub 3}Se{sub 2}O{sub 8} is orthorhombic, space group D{sub 2h}{sup 12}{minus}Pnnm, with unit cell constants a = 9.882(3), b = 11.774(3), c = 7.601(2) {angstrom}, T = 111 K, Z = 4. The structure has been solved and refined from single crystal x-ray diffraction data. The structure, including the oxygen content and positions, has been confirmed from neutron diffraction powder data. The asymmetric unit contains two independent Pr atoms, two independent Ta atoms, two independent Se atoms, five independent O atoms. The Pr atoms are in tricapped-trigonal prismatic sites enclosed by seven O and two Se atoms. One Ta atom is in a distorted octahedral site surrounded by six O atoms, and the other Ta atom is also in a distorted octahedral environment but has two trans O and four Se atoms in its coordination sphere.

  12. Single-Molecule Magnetism, Enhanced Magnetocaloric Effect, and Toroidal Magnetic Moments in a Family of Ln4 Squares.

    Science.gov (United States)

    Das, Chinmoy; Vaidya, Shefali; Gupta, Tulika; Frost, Jamie M; Righi, Mattia; Brechin, Euan K; Affronte, Marco; Rajaraman, Gopalan; Shanmugam, Maheswaran

    2015-10-26

    Three cationic [Ln4 ] squares (Ln=lanthanide) were isolated as single crystals and their structures solved as [Dy4 (μ4 -OH)(HL)(H2 L)3 (H2 O)4 ]Cl2 ⋅(CH3 OH)4 ⋅(H2 O)8 (1), [Tb4 (μ4 -OH)(HL)(H2 L)3 (MeOH)4 ]Cl2 ⋅(CH3 OH)4 ⋅(H2 O)4 (2) and [Gd4 (μ4 -OH)(HL)(H2 L)3 (H2 O)2 (MeOH)2 ]Br2 ⋅(CH3 OH)4 ⋅(H2 O)3 (3). The structures are described as hydroxo-centered squares of lanthanide ions, with each edge of the square bridged by a doubly deprotonated H2 L(2-) ligand. Alternating current magnetic susceptibility measurements show frequency-dependent out-of-phase signals with two different thermally assisted relaxation processes for 1, whereas no maxima in χM " appears above 2.0 K for complex 2. For 1, the estimated effective energy barrier for these two relaxation processes is 29 and 100 K. Detailed ab initio studies reveal that complex 1 possesses a toroidal magnetic moment. The ab initio calculated anisotropies of the metal ions in complex 1 were employed to simulate the magnetic susceptibility by using the Lines model (POLY_ANISO) and this procedure yields J1 =+0.01 and J2 =-0.01 cm(-1) for 1 as the two distinct exchange interactions between the Dy(III) ions. Similar parameters are also obtained for complex 1 (and 2) from specific heat measurements. A very weak antiferromagnetic super-exchange interaction (J1 =-0.043 cm(-1) and g=1.99) is observed between the metal centers in 3. The magnetocaloric effect (MCE) was estimated by using field-dependent magnetization and temperature-dependent heat-capacity measurements. An excellent agreement is found for the -ΔSm values extracted from these two measurements for all three complexes. As expected, 3 shows the largest -ΔSm variation (23 J Kg(-1)  K(-1) ) among the three complexes. The negligible magnetic anisotropy of Gd indeed ensures near degeneracy in the (2S+1) ground state microstates, and the weak super-exchange interaction facilitates dense population of low-lying excited states, all of

  13. Syntheses, Structure, Magnetism, and Optical Properties of the Partial Ordered Quaternary Interlanthanide Sulfides PrLnYb2S6 (Ln = Tb, Dy)

    Energy Technology Data Exchange (ETDEWEB)

    Booth, Corwin H; Jin, Geng Bang; Choi, Eun Sang; Guertin, Robert P.; Brooks, James S.; Bray, Travis H.; Booth, Corwin H.; Albrecht-Schmitt, Thomas E.

    2008-01-11

    Dark red single crystals of PrLnYb{sub 2}S{sub 6} (Ln = Pr/Yb, Tb, Dy) have been synthesized through the reaction of elemental rare earth metals and S using a Sb{sub 2}S{sub 3} flux at 1000 C. These isotypic compounds adopt the F-Ln{sub 2}S3 three-dimensional open channel structure type. Eight-coordinate Pr{sup 3+} ions sit in the channels, which are constructed from three different edge-shared double chains running down the b axis, which contain Yb(1)S{sub 6} octahedra, Yb(2)S{sub 6}, octahedra and LnS{sub 7} monocapped trigonal prisms, respectively. Each double chain connects to four other neighbors by sharing vertices and edges. Considerable disordering in Ln positions was observed in single X-ray diffraction experiments only in the case of Pr/Yb. Least square refinements gave rise to the formulas of Pr{sub 1.34}Yb{sub 2.66}S{sub 6}, of PrTbYb{sub 2}S{sub 6}, and PrDyYb{sub 2}S{sub 6}, which are confirmed by the elemental analysis and magnetic susceptibility measurements. Pr1.34Yb2.66S{sub 6}, PrTbYb{sub 2}S{sub 6} and PrDyYb{sub 2}S{sub 6} are paramagnetic down to 2 K without any indications of long range magnetic ordering. The optical transitions for Pr{sub 1.34}Yb{sub 2.66}S{sub 6}, PrTbYb{sub 2}S{sub 6}, and PrDyYb{sub 2}S{sub 6} are at approximately 1.6 eV. Crystallographic data: Pr{sub 1.34}Yb{sub 2.66}S{sub 6}, monoclinic, space group P2{sub 1}/m, a = 10.960(2), b = 3.9501(8), c = 11.220(2) {angstrom}, {beta} = 108.545(3), V = 460.54(16), Z = 2; PrTbYb{sub 2}S{sub 6}, monoclinic, space group P2{sub 1}/m, a = 10.9496(10), b = 3.9429(4), c = 11.2206(10) {angstrom}, {beta} = 108.525(2), V = 459.33(7), Z = 2; PrDyYb{sub 2}S{sub 6}, monoclinic, space group P2{sub 1}/m, a = 10.9384(10), b = 3.9398(4), c = 11.2037(10) {angstrom}, {beta} = 108.612(2), V = 457.57(7), Z = 2.

  14. Rare-earth metal methylidene complexes with Ln3(μ3-CH2)(μ3-Me)(μ2-Me)3 core structure.

    Science.gov (United States)

    Schädle, Dorothea; Meermann-Zimmermann, Melanie; Maichle-Mössmer, Cäcilia; Schädle, Christoph; Törnroos, Karl W; Anwander, Reiner

    2015-11-07

    Trinuclear rare-earth metal methylidene complexes with a Ln3(μ3-CH2)(μ3-Me)(μ2-Me)3 structural motif were synthesized by applying three protocols. Polymeric [LuMe3]n (1-Lu) reacts with the sterically demanding amine H[NSiMe3(Ar)] (Ar = C6H3iPr2-2,6) in tetrahydrofuran via methane elimination to afford isolable monomeric [NSiMe3(Ar)]LuMe2(thf)2 (4-Lu). The formation of trinuclear rare-earth metal tetramethyl methylidene complexes [NSiMe3(Ar)]3Ln3(μ3-CH2)(μ3-Me)(μ2-Me)3(thf)3 (7-Ln; Ln = Y, Ho, Lu) via reaction of [LnMe3]n (1-Ln; Ln = Y, Ho, Lu) with H[NSiMe3(Ar)] is proposed to occur via an "intermediate" species of the type [NSiMe3(Ar)]LnMe2(thf)x and subsequent C-H bond activation. Applying Lappert's concept of Lewis base-induced methylaluminate cleavage, compounds [NSiMe3(Ar)]Ln(AlMe4)2 (5-Ln; Ln = Y, La, Nd, Ho) were converted into methylidene complexes 7-Ln (Ln = Y, Nd, Ho) in the presence of tetrahydrofuran. Similarly, tetramethylgallate complex [NSiMe3(Ar)]Y(GaMe4)2 (6-Y) could be employed as a synthesis precursor for 7-Y. The molecular composition of complexes 4-Ln, 5-Ln, 6-Y and 7-Ln was confirmed by elemental analyses, FTIR spectroscopy, (1)H and (13)C NMR spectroscopy (except for holmium derivatives) and single-crystal X-ray diffraction. The Tebbe-like reactivity of methylidene complex 7-Nd with 9-fluorenone was assessed affording oxo complex [NSiMe3(Ar)]3Nd3(μ3-O)(μ2-Me)4(thf)3 (8-Nd). The synthesis of 5-Ln yielded [NSiMe3(Ar)]2Ln(AlMe4) (9-Ln; Ln = La, Nd) as minor side-products, which could be obtained in moderate yields when homoleptic Ln(AlMe4)3 were treated with two equivalents of K[NSiMe3(Ar)].

  15. Infected complex odontoma: an unusual presentation.

    Science.gov (United States)

    Agrawal, Bhavana; Gharote, Harshkant; Nair, Preeti; Shrivastav, Saurabh

    2012-08-24

    Odontomas represent a hamartomatous malformation. They are usually asymptomatic and are diagnosed on routine radiological examination .The eruption and infection of odontoma are uncommon. Till now, only 20 cases of erupted odontoma are reported in the literature. We report an unusual case of infected complex odontoma with eruption of odontoma in the oral cavity and perforation of the cheeks with a tooth impacted upon which makes the presentation unusual that has not been reported earlier. The dentist should be familiar with common and unusual appearance of odontoma for proper diagnosis and management.

  16. Unusual C,O-Fused Glycosylapigenins from Serjania marginata Leaves.

    Science.gov (United States)

    Heredia-Vieira, Silvia C; Simonet, Ana M; Vilegas, Wagner; Macías, Francisco A

    2015-01-23

    A phytochemical study of a Serjania marginata leaf extract with antiulcer activity afforded 15 compounds, including the new 3-O-α-l-arabinopyranosyl(1→3)-α-l-rhamnopyranosyl(1→2)[β-d-glucopyranosyl(1→4)]-α-l-arabinopyranosyloleanolic acid (1) and 7,5″-anhydroapigenin 8-C-α-(2,6-dideoxy-5-hydroxy-ribo-hexopyranosyl)-4'-O-β-d-glucopyranoside (4). The structures of the new compounds were determined by spectroscopic analysis, including 1D and 2D NMR techniques, mass spectrometry, and chemical methods. Compound 4 is a C-hexopyranosylapigenin with an unusual cyclic ether linkage between C-5″ and C-7 of apigenin. The isolated proanthocyanidins have high antioxidant activities, and these compounds are probably responsible for the gastroprotective effect of the extract.

  17. Magnetocaloric effect of a series of remarkably isostructural intermetallic [Ni(II)3Ln(III)] cubane aggregates.

    Science.gov (United States)

    Wang, Pei; Shannigrahi, Santiranjan; Yakovlev, Nikolai L; Hor, T S Andy

    2014-01-07

    A new series of remarkably isostructural 3d-4f compounds, [Ni3Ln(hmp)4(OAc)5]·H2O·CH2Cl2 (Ln = Gd (1), Tb (2), Dy (3), Ho (4), Y (5)) were synthesized based on a simple one-pot self-assembly method. Magnetic measurements demonstrated the ferromagnetic property of the [Ni3Ln] cores and the heterometallic influence on the magnetocaloric properties. This study suggested that robust and discrete intermetallic cubanes can be an alternative to other magnetically active materials such as high-nuclearity aggregates or clusters whose structures are not generally controlled by common synthetic methodological designs.

  18. Catalysis of the rare earth containing mixed oxides Ln2CuO4 in phenol hydroxylation

    Institute of Scientific and Technical Information of China (English)

    刘持标; 赵震; 叶兴凯; 吴越

    1997-01-01

    Mixed oxides Ln2CuO4±λ(Ln=La,Pr,Nd,Sm,Gd) with K2NiF4 structure were prepared Their crystal structures were studied with XRD and IR spectra.Meanwhile,the average valence of Cu ions and non stoichiometric oxygen (λ) were determined through chemical analyses.Catalysis of the above-mentioned mixed oxides in the phenol hydroxylation was investigated.Results show that the catalysis of these mixed oxides has close relation with their structures and composition.Substitution of A site atom in Ln2CuO4λ has a great influence on then eatalysis in the phenol hydroxylation.

  19. Octanuclear [Ni(II)₄Ln(III)₄] complexes. Synthesis, crystal structures and magnetocaloric properties.

    Science.gov (United States)

    Pasatoiu, Traian D; Ghirri, Alberto; Madalan, Augustin M; Affronte, Marco; Andruh, Marius

    2014-06-28

    Two original heterooctanuclear [Ni(II)4Ln(III)4] complexes (Ln(III) = Sm(III), Gd(III)) have been obtained starting from the [Ni(II)(valpn)(H2O)2] mononuclear precursor [H2valpn = 1,3-propanediylbis(2-iminomethylene-6-methoxy-phenol)] and the corresponding lanthanide nitrates, in the presence of azide anions, through slow capture of atmospheric CO2. Three weak and competitive exchange interactions, J(GdGd), J(GdNi), J(NiNi), make the ground state of this magnetic system degenerate at cryogenic temperature and zero field. This, along with the high spin of Gd(III), lead to a significant magnetocaloric effect spread in the temperature range 1 to 20 K (ΔSm[0-7 T, 3.5 K] = 19 J kg(-1) K(-1)).

  20. Martensitic transformation during fatigue testing of an AISI 301LN steel

    OpenAIRE

    Mateo García, Antonio Manuel; Fargas Ribas, Gemma

    2012-01-01

    The plastic deformation accumulated during fatigue testing can induce the transformation of austenite to martensite in metastable austenitic stainless steels. To analyze this issue, a metastable austenitic stainless steel grade AISI 301 LN was studied in two different conditions, i.e. annealed and cold rolled. In the first case, the steel was fully austenitic, whereas cold rolled material had almost 30% of martensite. High cycle fatigue tests at a stress ratio of 0.8 were carried out on flat ...

  1. Analytic Amplitudes for Hadronic Forward Scattering and the Heisenberg ln**2 Behaviour of Total Cross Sections

    CERN Document Server

    Nicolescu, B

    2004-01-01

    The ln**2 behaviour of total cross sections, first obtained by Heisenberg 50 years ago, receives now increased interest both on phenomenological and theoretical levels. We present a modification of the Heisenberg's model in connection with the presence of glueballs and we show that it leads to a realistic description of all existing hadron total cross-section data, in agreement with the COMPETE analysis.

  2. Study of LnBaCo{sub 2}O{sub 6-d}elta (Ln = Pr, Nd, Sm and Gd) double perovskites as new cathode material for IT-SOFC

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, E; Mueller, M; Mogni, L; Caneiro, A, E-mail: mogni@cab.cnea.gov.a [Centro Atomico Bariloche-CNEA, Instituto Balseiro. Av. Bustillo 9500, S. C. de Bariloche 8400 (Argentina)

    2009-05-01

    Oxides with double perovskites structures of general composition LnBaCo{sub 2}O{sub 6-d}elta (Ln = Pr, Nd, Sm and Gd) were synthesized by solid state reaction with the purpose to evaluate new materials to be used as cathodes in intermediate temperature solid oxide fuel cell (IT-SOFC). A preliminary study about electrochemical properties was performed by impedance spectroscopy between 500 and 800 deg. C under atmosphere of pure O{sub 2}. Symmetrical cells were obtained by spray deposition of LnBaCo{sub 2}O{sub 6-d}elta (Ln = Pr, Nd, Sm and Gd) at both sides of a dense ceramic electrolyte. The impedance spectroscopy measurements as a function of temperatures show a hysteresis loop which could be associated to a tetragonal/orthorhombic phase transition. The existence of this transition was corroborated by high temperature X-Ray diffraction and Differential Scanning Calorimetry measurements.

  3. Equipping an FPGA-Based Mars Rover With an LN-200 IMU

    Science.gov (United States)

    Zola, Nicholas J.

    2005-01-01

    The Mars Exploration Rovers (MER) currently navigating the surface of Mars are outfitted with an advanced stereovision correlation algorithm which allows them to "see" three-dimensionally and autonomously avoid obstac'les in their path. A bottleneck of this system is that it is computationally intense and requires 3 minutes of processing for every correlated image and path choice. Taking advantage of the optimization and reprogrammability of FPGAs, the Mobility Avionics lab has reduced this process to under a second. The lab is demonstrating the advancement with a prototype rover, complete with an LN-200 inertial measurement unit (IMU), which is a flight spare from MER. The LN-200 is a space-grade, six degrees-of-freedom IMU using three fiber-optic gyroscopes and three silicon accelerometers and no moving parts. It has particular power-sequencing needs and communicates with a specialized serial protocol (SDLC over RS-422), requiring specific hardware and software for proper functionality and interfacing with an FPGA. The process of incorporating the LN-200 into the system is described herein.

  4. Low-x contribution to the Bjorken sum rule within double logarithmic $ln^2x$ approximation

    CERN Document Server

    Kotlorz, D; Kotlorz, Dorota; Kotlorz, Andrzej

    2004-01-01

    The small-$x$ contributions to the Bjorken sum rule within double logarithmic $ln^2x$ approximation for different input parametrisations $g_1^{NS}(x,Q_0^2)$ are presented. Analytical solutions of the evolution equations for full and truncated moments of the unintegrated structure function $f^{NS}(x,Q^2)$ are used. Theoretical predictions for $\\int_{0}^{0.003} g_1^{NS}(x,Q^2=10) dx$ are compared with the SMC small-$x$ data. Rough estimation of the slope $\\lambda$, controlling the small-$x$ behaviour of $g_1^{NS}\\sim x^{-\\lambda}$ from the SMC data is performed. Double logarithmic terms $\\sim (\\alpha_s ln^2x)^n$ become leading when $x\\to 0$ and imply the singular behaviour of $g_1^{NS}\\sim x^{-0.4}$. This seems to be confirmed by recent experimental SMC and HERMES data. Advantages of the unified $ln^2x$+LO DGLAP approach and the crucial role of the running coupling $\\alpha_s=\\alpha_s(Q^2/z)$ at low-$x$ are also discussed.

  5. An unusual case of lingual tonsillar hypertrophy.

    Science.gov (United States)

    Hope, Nicholas; Patricia Smith, Caroline; Moran, Michael; Primrose, William

    2016-05-01

    Lingual tonsillar hypertrophy is an unusual presentation of voice change. If managed incorrectly this group of patients has the potential to deteriorate significantly causing airway obstruction and potentially death.

  6. An unusual presentation of tuberculosis in pregnancy

    Institute of Scientific and Technical Information of China (English)

    GAO Xue-lian; Rajat Gyaneshwar

    2007-01-01

    @@ Tuberculosis (TB) is a systemic infection caused by Mycobacterium tuberculosis. Extrapulmonary TB accounts for 10% to 27% of all the patients with TB.1 Here we report an unusual case of extrapulmonary TB in a pregnant woman.

  7. Unusual foreign bodies of upper gastrointestinal tract.

    Science.gov (United States)

    Nijhawan, S; Rai, R R; Agarwal, S; Vijayvergiya, R

    1995-01-01

    We report management of unusual foreign bodies of upper gastrointestinal tract, namely beer bottle cap, raisins and pistachu, mango peel, betelnut and plum seed at a university hospital in Northern India.

  8. An unusual cause of gastrointestinal bleed

    Directory of Open Access Journals (Sweden)

    C K Adarsh

    2014-01-01

    Full Text Available Gastrointestinal (GI bleed often brings the patient to the emergency medical service with great anxiety. Known common causes of GI bleed include ulcers, varices, Mallory-Weiss among others. All causes of GI bleed should be considered however unusual during the evaluation. Aortoenteric fistula (AEF is one of the unusual causes of GI bleed, which has to be considered especially in patients with a history of abdominal surgery in general and aortic surgery in particular.

  9. Synthesis and Structures of Two Lanthanide Complexes Containing a Mixed Ligand System: [Ln(Phen){sub 2}(L){sub 3}(HL)]·H{sub 2}O [Ln = La, Ce; Phen = Phenanthroline; HL = Salicylic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Iravani, Effat [UNiv. of Applied Science and Technology, Tehran (Iran, Islamic Republic of); Nami, Navabeh; Nabizadeh, Fatemeh; Bayani, Elham [Islamic Azad Univ., Mazandaran (Iran, Islamic Republic of); Neumueller, Bernhard [Philipps-Universitat Marburg, Marburg (Germany)

    2013-11-15

    The reaction of LnCl{sub 3}·7H{sub 2}O [Ln = La (1), Ce (2)] with salicylic acid (HL) and 1,10-phenanthroline (Phen) at 20 .deg. C in H{sub 2}O/ethanol gave after work-up and recrystallization two novel lanthanide complexes with general formula [Ln(Phen){sub 2}(L){sub 3}(HL)]·H{sub 2}O. Compounds 1 and 2 were characterized by IR and UV-Vis spectroscopy, TGA, CHN as well as by X-ray analysis. According to these results, compounds 1 and 2 are isostructural and contain Ln{sup 3+} ions with coordination number nine. Complexes 1 and 2 consist of two Phen, one neutral HL and three L anions (two L anions act as monodentate ligands and the third one is chelating to Ln{sup 3+}). Thermal decomposition led to primary loss of the Phen molecules. Then HL molecules and finally L moieties left the material to give Ln{sub 2}O{sub 3}.

  10. Synthesis and photoluminescence studies of Ba(Gd,Ln)B9O16:Eu3+(Ln=La,Y) phosphors for n-UV LED lighting and display devices

    Institute of Scientific and Technical Information of China (English)

    V.V. Rangari; S.J. Dhoble

    2015-01-01

    BaGdB9O16:Eu3+ and Ba(Gd,Ln)B9O16:Eu3+(Ln=La, Y) phosphors were synthesized by solid state diffusion method. The X-ray diffraction, scanning electron microscopy (SEM) and photoluminescence properties were investigated. The as-synthesized BaGdB9O16:Eu3+and Ba(Gd,Ln)B9O16:Eu3+(Ln=La, Y) phosphors showed strong red emission under ultraviolet light excitation. By partially substituting Gd3+by La3+and Y3+ions in the host BaGdB9O16:Eu3+materials, the maximum emission intensity was observed for the optimum composition of BaGd0.91La0.8B9O16Eu0.01 phosphor. The experimental results indicated that the Eu doped BaGdB9O16 and Ba(Gd,Ln)B9O16 (Ln=La, Y) phosphors were promising red phosphors, which might find po-tential applications in near-UV excited LED lighting as well as display devices. Comparison of as-synthesized phosphors with standard phosphor used in CFL (compact fluorescent lamp) was also done. Energy transfer mechanism of Gd3+to Eu3+was also discussed in this paper.

  11. Interesting bone scans - unusual findings

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, M.; Wadhwa, S.S.; Mansberg, R.; Fernandes, V.B. [Wollongong Hospital, Wollongong, NSW (Australia)

    1997-12-01

    fibrous dysplasia. Three cases with interesting and unusual bone scan findings assisted in further management and treatment of patients

  12. Structural and IR-spectroscopic characterization of some new Sr{sub 2}LnSbO{sub 6} perovskites

    Energy Technology Data Exchange (ETDEWEB)

    Lavat, Araceli E. [Departamento de Ingenieria Quimica, Facultad de Ingenieria, Universidad Nacional del Centro de la Provincia de Buenos Aires, 7400 Olavarria (Argentina); Baran, Enrique J. [Centro de Quimica Inorganica (CEQUINOR/CONICET, UNLP), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C. Correo 962, 1900 La Plata (Argentina)], E-mail: baran@quimica.unlp.edu.ar

    2008-07-28

    A series of ternary perovskite-type oxides of composition Sr{sub 2}LnSbO{sub 6} (with Ln = La, Nd, Sm, Gd, Dy, Er, Yb and Y), have been prepared and their unit cell parameters determined by X-ray powder diffractometry. The infrared spectra of these materials were also recorded and briefly discussed on the basis of their structural peculiarities and by comparison with those of related oxides.

  13. Energy Equality and Uniqueness of Weak Solutions to MHD Equations in L∞(O,T;Ln(Ω))

    Institute of Scientific and Technical Information of China (English)

    Yan YONG; Quan Sen JIU

    2009-01-01

    In this paper, we study the energy equality and the uniqueness of weak solutions to the MHD equations in the critical space L∞(O,T; Ln(Ω)). We prove that if the velocity u belongs to the critical space L∞(O,T; Ln(Ω)), the energy equality holds. On the basis of the energy equality, we further prove that the weak solution to the MHD equations is unique.

  14. A facile single-step procedure for the synthesis of luminescent Ln{sup 3+}:YVO{sub 4} (Ln = Eu or Er + Yb)-silica nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Ocana, Manuel, E-mail: mjurado@icmse.csic.es [Instituto de Ciencia de Materiales de Sevilla, CSIC-US, Americo Vespucio 49, 41092 Isla de la Cartuja, Sevilla (Spain); Cantelar, Eugenio; Cusso, Fernando [Depto. Fisica de Materiales, C-IV, Universidad Autonoma de Madrid (Spain)

    2011-01-01

    A simple and single-step method for the production of Ln-doped YVO{sub 4} nanocrystals and their simultaneous encapsulation in a silica network based on the pyrolysis of liquid aerosols at 800 deg. C is reported. The procedure is illustrated for Yb,Er:YVO{sub 4}-silica nanocomposites consisting of spherical particles, which present up-converted green luminescence after IR excitation whose efficiency increased on annealing up to 1000 deg. C due to the release of impurities (adsorbed water, and residual anions). XPS spectroscopy and TEM observations revealed that the surface of the composite particles was enriched in silica, which would facilitate their functionalisation required to use them in biological applications. The procedure can also be used to prepare other rare earth doped systems as illustrated for the case of Eu-doped YVO{sub 4}/silica having down-converted red luminescence.

  15. Two New Octadecanuclear Copper(II)-Lanthanide(III) Clusters Encapsulating μ9-NO -3 Anions. Synthesis, Structures, and Magnetic Properties of [Cu 12Ln6( μ3-OH) 24(C 5H 5NCH 2CO 2) 12(H 2O) 18( μ9-NO 3)](PF 6) 10(NO 3) 7·12H 2O ( LnIII=Sm III or Gd III)

    Science.gov (United States)

    Yang, Yang-Yi; Chen, Xiao-Ming; Ng, Seik Weng

    2001-11-01

    Two new octadecanuclear clusters [Cu12Ln6(μ3-OH)24(C5H5NCH2CO2)12(H2O)18(μ9-NO3)](PF6)10(NO3)7·12H2O [LnIII=SmIII (1) or GdIII (2)] have been synthesized and characterized by X-ray diffraction. They are isomorphous and crystallize in the triclinic space group Poverline1 with Z=1. The cell dimensions of 1 are a=17.366(1), b=17.790(1), and c=19.002(1) Å, α=117.279(1), β=91.763(1), and γ=111.585(1)°. In the cluster, 6 SmIII atoms are positioned at the vertices of an octahedron, while 12 CuII atoms are at the midpoints of the edges of the octahedron. The CuII-SmIII metal framework is interconnected by the 24 similar μ3-OH- groups, each bridging one SmIII and two CuII atoms. The octahedral cage encapsulates an unusual μ9-NO-3 anion with each oxygen atom coordinated to three CuII atoms. The 12 carboxylate ligands act as μ2-carboxylate-O,O‧ bridges, each linking a SmIII and a CuII atom. The PF-6 counteranion plays an important role in crystallization of the two complexes.

  16. Synthesis and crystal structure determination of some polymetallic oxalates of U{sup IV}, Na, Ln{sup III} (Ln = Ce and Nd)

    Energy Technology Data Exchange (ETDEWEB)

    Chapelet-Arab, B.; Grandjean, S.; Nowogrocki, G.; Abraham, F

    2004-07-01

    In the course of investigations of oxalic coprecipitation of uranium(IV) and cerium (III) an oxalate containing also sodium ions was isolated. Its structure was determined by single crystal X-ray diffraction and led to the formula (U{sub 1}Ce{sub 1})Na{sub 3}(C{sub 2}O{sub 4}){sub 5} 10.4H{sub 2}O. Astonishingly, the two heavy metallic ions occupy the same crystallographic site, the alkaline ion assuring the charge neutrality. This behaviour has also been evidenced on two oxalates of uranium(IV) and neodymium(III) exhibiting various ratio U(IV)/Nd(III). Though (U{sub 1.44}Nd{sub 0.56})Na{sub 2.4}(C{sub 2}O{sub 4}){sub 5} 10H{sub 2}O and (U{sub 1}Ce{sub 1})Na{sub 3}(C{sub 2}O{sub 4}){sub 5} 10.4H{sub 2}O present different ratio U(IV)/Ln(III), their crystallographic structures are similar. In these three-dimensional structural arrangements, uranium(IV) and lanthanide(III) are surrounded by five bidentate oxalate units and water molecules lie in the middle of (U,Ln){sub 3}(C{sub 2}O{sub 4}){sub 6} honeycomb hexagonal six-membered rings. Although the synthesis conditions are close, (U{sub 1}Nd{sub 1})Na(C{sub 2}O{sub 4}){sub 4} 8H{sub 2}O is built from an unlike coordination polyhedra which is constituted of four bidentate oxalate ligands and one water molecule.

  17. Host-sensitized luminescence properties in CaNb2O6:Ln(3+) (Ln(3+) = Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+)) phosphors with abundant colors.

    Science.gov (United States)

    Li, Kai; Liu, Xiaoming; Zhang, Yang; Li, Xuejiao; Lian, Hongzhou; Lin, Jun

    2015-01-05

    A series of Ln(3+) (Ln(3+) = Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+)) ion doped CaNb2O6 (CNO) phosphors have been prepared via the conventional high-temperature solid-state reaction route. The X-ray diffraction (XRD) and structure refinement, diffuse reflection, photoluminescence (PL), and fluorescent decay curves were used to characterize the as-prepared samples. Under UV radiation, the CNO host present a broad emission band from about 355 to 605 nm centered around 460 nm originating from the NbO6 octahedral groups, which has spectral overlaps with the excitation of f-f transitions of Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+) in CNO:Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+) samples. They show both host emission and respective emission lines derived from the characteristic f-f transitions of activators, which present different emission colors owing to the energy transfer from the NbO6 group in the host to Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+) with increasing activator concentrations. The decreases of decay lifetimes of host emissions in CNO:Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+) demonstrate the energy transfer from the hosts to Eu(3+)/Tb(3+)/Dy(3+)/Sm(3+). The energy transfer mechanisms in CNO:Eu(3+)/Tb(3+)/Dy(3+) phosphors have been determined to be a resonant type via dipole-dipole mechanisms. For CNO:Sm(3+), the metal-metal charge transfer transition (MMCT) might contribute to the different variations of decay lifetimes and emission intensity from CNO:Eu(3+)/Tb(3+)/Dy(3+) samples. The best quantum efficiency is 71.2% for CNO:0.01/0.02Dy(3+). The PL properties of as-prepared materials indicate the promising application in UV-pumped white-emitting lighting diodes field.

  18. Synthesis and photocatalytic property of layered perovskite tantalates, RbLnTa{sub 2}O{sub 7} (Ln = La, Pr, Nd, and Sm)

    Energy Technology Data Exchange (ETDEWEB)

    Machida, Masato; Yabunaka, Junichi; Kijima, Tsuyoshi

    2000-03-01

    The first example of an active layered tantalate photocatalyst containing partly filled lanthanide 4f shell is reported. A single phase of layered perovskite tantalates, RbLnTa{sub 2}O{sub 7}, could be obtained with Ln = La, Pr, Nd, and Sm; the ionic radii of these trivalent cations are required to be larger than 0.126 nm for constructing a perovskite slab. Under UV irradiation from a high-pressure Hg lamp, these layered tantalates demonstrated the photocatalytic activity for water splitting into stoichiometric H{sub 2}/O{sub 2} mixtures even without loading metal catalysts. The rates of H{sub 2} and O{sub 2} evolutions were found to be strongly dependent on the lanthanoids, increasing in the sequence of La {approx} Pr << Sm < Nd. The maximum rate of H{sub 2} evolution observed over RbNdTa{sub 2}O{sub 7} reached 47.0 {micro}mol/h. The absorption spectrum of RbNdTa{sub 2}O{sub 7} consists of the internal 4f transitions in the visible region and a broad band overlapping the band-gap transition in the UV region. The latter band indicates that a possible excitation process including the partly filled 4f shell plays a key role in photocatalytic reactions. Loading 0.5 wt % Ni onto RbNdTa{sub 2}O{sub 7} by simple impregnation significantly improved H{sub 2} evolution (117.2 {micro}mol/h).

  19. Effect of Lactobacillus buchneri LN4637 and Lactobacillus buchneri LN40177 on the aerobic stability, fermentation products, and microbial populations of corn silage under farm conditions.

    Science.gov (United States)

    Tabacco, E; Piano, S; Revello-Chion, A; Borreani, G

    2011-11-01

    This study determined the efficacy of the use of 2 commercial inoculants containing Lactobacillus buchneri alone or in combination with homofermentative lactic acid bacteria in improving aerobic stability of corn silage stored in commercial farm silos in northern Italy. In the first survey, samples were collected from 10 farms that did not inoculate their silages and from 10 farms that applied a Pioneer 11A44 inoculant (L. buchneri strain LN4637; Pioneer Hi-Bred International, Des Moines, IA). In the second survey, corn silage samples were collected from 11 farms that did not inoculate their silages and from 11 farms that applied a Pioneer 11CFT inoculant (L. buchneri strain LN40177; Pioneer Hi-Bred International). Inoculants were applied directly through self-propelled forage harvesters, at the recommended rate of 1 g/t of fresh forage, to achieve a final application rate of 1.0 × 10(5) cfu/g of L. buchneri. One corn bunker silo, which had been open for at least 10 d, was examined in detail on each farm. The silages inoculated with L. buchneri had lower concentrations of lactic acid, a lower lactic-to-acetic acid ratio, a lower yeast count, and higher aerobic stability compared with the untreated silages. Unexpectedly, concentrations of acetic acid and 1,2-propanediol, 2 hallmarks of L. buchneri activity, did not differ between treatments and were only numerically higher in the inoculated silages compared with untreated ones, in both surveys. Aerobic stability, on average, was 107 and 121 h in the inoculated silages and 64 and 74 h in the untreated silages, for surveys 1 and 2, respectively, and decreased exponentially as the yeast count in the silage at the time of sampling increased, regardless of treatment. Inoculation with L. buchneri proved to be effective in reducing the yeast count to corn silages in farm bunker silos. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. Hydrothermal synthesis, structure, and optical properties of two nanosized Ln{sub 26} rate at CO{sub 3} (Ln=Dy and Tb) cluster-based lanthanide-transition-metal-organic frameworks (Ln MOFs)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu; Huang, Lian; Miao, Hao; Wan, Hong Xiang; Mei, Hua; Liu, Ying [State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University (China); Xu, Yan [State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University (China); State Key Laboratory of Coordination Chemistry, Nanjing Tech University (China)

    2015-02-16

    Two Ln{sub 26} rate at CO{sub 3} (Ln=Dy and Tb) cluster-based lanthanide-transition-metal-organic frameworks (Ln MOFs) formulated as [Dy{sub 26}Cu{sub 3}(Nic){sub 24}(CH{sub 3}COO){sub 8}(CO{sub 3}){sub 11}(OH){sub 26}(H{sub 2}O){sub 14}]Cl . 3 H{sub 2}O (1; HNic=nicotinic acid) and [Tb{sub 26}NaAg{sub 3}(Nic){sub 27}(CH{sub 3}COO){sub 6}(CO{sub 3}){sub 11}(OH){sub 26}Cl(H{sub 2}O){sub 15}] . 7.5 H{sub 2}O (2) have been successfully synthesized by hydrothermal methods and characterized by IR, thermogravimetric analysis (TGA), elemental analysis, and single X-ray diffraction. Compound 1 crystallizes in the monoclinic space group Cc with a=35.775(12) Aa, b=33.346(11) Aa, c=24.424(8) Aa, β=93.993(5) , V=29065(16) Aa{sup 3}, whereas 2 crystallizes in the triclinic space group P anti 1 with a=20.4929(19) Aa, b=24.671(2) Aa, c=29.727(3) Aa, α=81.9990(10) , β=88.0830(10) , γ=89.9940(10) , V=14875(2) Aa{sup 3}. Structural analysis indicates the framework of 1 is a 3D perovskite-like structure constructed out of CO{sub 3} rate at Dy{sub 26} building units and Cu{sup +} centers by means of nicotinic acid ligand bridging. In 2, however, nanosized CO{sub 3} rate at Tb{sub 26} units and [Ag{sub 3}Cl]{sup 2+} centers are connected by Nic{sup -} bridges to give rise to a 2D structure. It is worth mentioning that this kind of 4d-4f cluster-based MOF is quite rare as most of the reported analogous compounds are 3d-4f ones. Additionally, the solid-state emission spectra of pure compound 2 at room temperature suggest an efficient energy transfer from the ligand Nic{sup -} to Tb{sup 3+} ions, which we called the ''antenna effect''. Compound 2 shows a good two-photon absorption (TPA) with a TPA coefficient of 0.06947 cm GM{sup -1} (1 GM = 10{sup -50} cm{sup 4} s photon{sup -1}), which indicates that compound 2 might be a good choice for third-order nonlinear optical materials. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Disrupted Stars in Unusual Galaxies

    Science.gov (United States)

    Kohler, Susanna

    2016-03-01

    Tidal disruption events (TDEs) occur when a star passes a little too close to a supermassive black hole at the center of a galaxy. Tidal forces from the black hole cause the passing star to be torn apart, resulting in a brief flare of radiation as the stars material accretes onto the black hole. A recent study asks the following question: do TDEs occur most frequently in an unusual type of galaxy?A Trend in DisruptionsSo far, we have data from eight candidate TDEs that peaked in optical and ultraviolet wavelengths. The spectra from these observations have shown an intriguing trend: many of these TDEs host galaxies exhibit weak line emission (indicating little or no current star-formation activity), and yet they show strong Balmer absorption lines (indicating star formation activity occurred within the last Gyr). These quiescent, Balmer-strong galaxies likely underwent a period of intense star formation that recently ended.To determine if TDEs are overrepresented in such galaxies, a team of scientists led by Decker French (Steward Observatory, University of Arizona) has quantified the fraction of galaxies in the Sloan Digital Sky Survey (SDSS) that exhibit similar properties to those of TDE hosts.Quantifying OverrepresentationSpectral characteristics of SDSS galaxies (gray) and TDE candidate host galaxies (colored points): line emission vs. Balmer absorption. The lower right-hand box identifies thequiescent, Balmer-strong galaxies which contain most TDE events, yet are uncommon among the galaxy sample as a whole. Click for a better look! [French et al. 2016]French and collaborators compare the optical spectra of the TDE host galaxies to those of nearly 600,000 SDSS galaxies, using two different cutoffs for the Balmer absorption the indicator of past star formation. Their strictest cut, filtering for very high Balmer absorption, selected only 0.2% of the SDSS galaxies, yet 38% of the TDEs are hosted in such galaxies. Using a more relaxed cutoff selects 2.3% of

  2. Unexplained Brightening of Unusual Star

    Science.gov (United States)

    1997-01-01

    Recent observations with the Hubble Space Telescope (HST) have documented an unexpected and rapid, seven-fold brightening of an unusual double star at the centre of the impressive 47 Tucanae globular cluster in the southern sky. This is the first HST observation of such a rare phenomenon. The astronomers [1] who are involved in this observational program find that this event cannot be explained by any of the common processes known to occur in such stars. The cores of globular clusters Globular clusters are like huge swarms of stars, containing about one million suns, which move around in their common gravitational field. Most galaxies contain globular clusters; around 150 are known within the confines of our Galaxy, the Milky Way. Globular clusters change with time. In particular, at some stage in the life of a globular cluster, its central region will contract whereby the stars there move closer to each other. This phenomenon is referred to as core collapse [2]. Observations with the Hubble Space Telescope (HST) have revealed enormous central densities of the order of 30,000 stars per cubic light-year in clusters with fully collapsed cores; this is to be compared with the stellar density in the solar neighborhood of only 0.003 stars per cubic light-year [3]. Binary stars in globular clusters Binary (i.e., double) stars play an important role in the evolution of globular clusters: they can delay, halt, or even reverse the process of core collapse. In this dense stellar environment, close encounters between passing stars and binaries are relatively frequent. Such events may leave the binary stars more tightly bound, and at the same time speed up the motion of the stars involved, thereby counteracting the contraction of the core. The same close stellar encounters may also produce a diverse progeny of exotic objects. The centers of globular clusters contain blue stragglers (stars that ``look'' younger than they really are), millisecond pulsars (rapidly rotating, very

  3. Facile patterning of luminescent GdVO{sub 4}:Ln (Ln = Eu{sup 3+}, Dy{sup 3+}, Sm{sup 3+}) thin films by microcontact printing process

    Energy Technology Data Exchange (ETDEWEB)

    Wang Dong; Yang Piaoping; Cheng Ziyong, E-mail: zycheng@ciac.jl.cn; Wang Wenxin; Ma Pingan; Zhai Xuefeng; Lin Jun, E-mail: jlin@ciac.jl.cn [Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, State Key Laboratory of Rare Earth Resource Utilization (China)

    2012-01-15

    Ordered arrays of luminescent GdVO{sub 4}:Ln (Ln = Eu{sup 3+}, Dy{sup 3+}, Sm{sup 3+}) films with dot patterns have been successfully fabricated via microcontact printing method. The soft-lithography process utilizes a PDMS elastomeric mold as the stamp combined with a Pechini-type sol-gel process to produce luminescent patterns on quartz plates, in which a GdVO{sub 4}:Ln (Ln = Eu{sup 3+}, Dy{sup 3+}, Sm{sup 3+}) precursor solution was employed as ink. The ordered luminescent GdVO{sub 4}:Ln patterns were revealed by optical microscopy and their microstructure, consisting of nanometer-scale particles, as demonstrated by scanning electronic microscopy observations. In addition, photoluminescence and cathodoluminescence were carried out to characterize the patterned GdVO{sub 4}:Ln (Ln = Eu{sup 3+}, Dy{sup 3+}, Sm{sup 3+}) samples. Upon UV-light or electron-beam irradiation, the rare earth ions Eu{sup 3+}, Dy{sup 3+}, and Sm{sup 3+} in the crystalline GdVO{sub 4} host show their characteristic transitions dominated by {sup 5}D{sub 0}-{sup 7}F{sub 2}, {sup 4}F{sub 9/2}-{sup 6}H{sub 13/2} ,and {sup 4}G{sub 5/2}-{sup 6}H{sub 7/2}, respectively. These results make the combining soft lithography with a Pechini-type sol-gel route have potential applications as rare-earth luminescent pixels for next-generation field-emission display devices.

  4. Genus specific unusual carotenoids in purple bacteria, Phaeospirillum and Roseospira: structures and biosyntheses.

    Science.gov (United States)

    Takaichi, Shinichi; Maoka, Takashi; Sasikala, Ch; Ramana, Ch V; Shimada, Keizo

    2011-07-01

    Phototrophic bacteria necessarily contain carotenoids for photosynthesis, and a few phototrophic purple bacteria accumulate unusual carotenoids. The carotenoids in the genera Phaeospirillum and Roseospira were identified using spectroscopic methods. All species of the genus Phaeospirillum contained characteristic polar carotenoids in addition to lycopene and hydroxylycopene (rhodopin); hydroxylycopene glucoside, dihydroxylycopene, and its mono- and/or diglucosides. From the structures of these carotenoids, their accumulation was suggested to be due to absence of CrtD (acyclic carotenoid C-3,4 desaturase) and to possession of glucosyltransferase. Species of the genus Roseospira have been reported to have unusual absorption spectra in acetone extract, and they were found to accumulate 3,4-didehydrorhodopin as a major carotenoid. This may be due to low activity of CrtF (acyclic 1-hydroxycarotenoid methyltransferase). The study concludes in identifying genus specific unusual carotenoids, which is probably due to characteristic nature of some carotenogenesis enzymes.

  5. Crystal Structure of Rare Earth Acrylates[Ln2(CH2 CHCOO)6·3H2O]·3H2O(Ln=Ce,Nd)%两种丙烯酸盐[Ln2(CH2CHCOO)6·3H2O]·3H2O(Ln=Ce;Nd)的单晶结构

    Institute of Scientific and Technical Information of China (English)

    钱玉英; 褚晓东; 姚有为

    2011-01-01

    Crystal strudures of [Ln2 (CH2CHCOO)6·3H2O](Ln = Ce,Nd) were characterized by using X - ray single crystal analysis. The title compounds are iso - structural: monoclime system, apace group P21/c with a= 1.02099 (13)nm,b = 1.52294(19) nm,c = 2.0325(3) nm,β= 100.838 (2)°, V = 3.1039 (7) nm3 for [ Ce2 ( CH2CHCOO) 6·3H2O] ;α=1.01978(8) nm, b=1.50979 (12) nm, c=2.02712 (16) nm,β=100.881 (1)°, V = 3.0650 (4) nm3 for [ND2 (CH2CHCOO)6·3H2O]. There are two independent Ln ions in the asymmetric unit, which are located in nona - coor-dinated and deca - coordinated environments respectively. The two Ln ions are bridged togetber by two μ2 - oxygen atoms of two independent acrylates, resulting in left - handed and right - handed helical chains. Hydrogen network are built up from helical chains and water molecules located between two neighbor chains. giying rise to three - dimensional stack.%采用X射线单晶衍射法,解析了[Ln2(CH:CHCOO)6·3H2O]·3H2O(Ln=Ce;Nd)的结构.结果表明标题化合物属同构:属单斜晶系(空间群P2(1)/c);[Ce2(CH2CHCOO)6·3H2O]·3H2O晶胞参数α=1.02099(13)nm,b=1.52294(19)nm,c=2.0325(3)nin,/3=100.838(2)°,V=3.1039(7)nm3;[Nd2(CH2CHCOO)6·3H2O]·3H2O晶胞参数α=1.01978(8)nm,6=1.50979(12)nm,c=2.02712(16)nm,β=100.881(1)°,V=3.0650(4)nm3.化合物不对称结构单元中含有两个独立的稀土中心离子,分别处九、十配位环境中.两个稀土离子由两个独立的丙烯酸μ2-氧桥联形成左手和右手螺旋链.螺旋链通过链间的水分子形成氢键网络,堆垛成三维结构.

  6. Simultaneous observation of low temperature 4f-4f and 3d-3d emission spectra in a series of Cr(III)(ox)Ln(III) assembly

    CERN Document Server

    Subhan, M A; Suzuki, T; Choi, J H; Kaizaki, S

    2003-01-01

    We report here the low temperature emission spectra in the heterometal dinuclear 3d-4f assembled molecular system [(acac) sub 2 Cr sup I sup I sup I (mu-ox)Ln sup I sup I sup I (HBpz sub 3) sub 2] (Cr(ox)Ln:acac sup - =acetylacetonate, ox sup 2 sup - =oxalate, HBpz sub 3 sup - =hydrotris(pyrazol-1-yl)borate; Ln=La, Nd, Ho, Er , Tm and Yb) in comparison with those of Na[Cr(acac) sub 2 (ox)] and [(HBpz sub 3) sub 2 Ln(mu-ox)Ln(HBpz sub 3) sub 2](Ln=Nd and Er). From 10 to 150 K the Cr(ox)Ln complexes show a broad emission band around 800 nm from the sup 2 E state of Cr(III) moiety. At room temperature no sup 2 E- sup 4 A sub 2 emission was observed in the Cr(ox)Ln except for the La and Lu complexes. On warming from 10 to 300 K rapid quenching of the sup 2 E- sup 4 A sub 2 emission of Cr(III) is suggested to result from the energy transfer from Cr to Ln in the Cr(ox)Ln. The excitation spectra and the life-time were also measured with monitoring the 4f-4f emission peaks of the Cr(ox)Yb complex.

  7. Agreement between a smart-phone pulse sensor application and ECG for determining lnRMSSD.

    Science.gov (United States)

    Esco, Michael R; Flatt, Andrew A; Nakamura, Fabio Y

    2016-06-27

    The purpose of this study was to determine the agreement between a smartphone pulse finger sensor (SPFS) and electrocardiography (ECG) for determining ultra-short-term heart rate variability (HRV) in three different positions. Thirty college-aged men (n = 15) and women (n = 15) volunteered to participate in this study. Sixty second heart rate measures were simultaneously taken with the SPFS and ECG in supine, seated and standing positions. lnRMSSD was calculated from the SPFS and ECG. The lnRMSSD values were 81.5 ± 11.7 via ECG and 81.6 ± 11.3 via SPFS (p = 0.63, Cohen's d = 0.01) in the supine position, 76.5 ± 8.2 via ECG and 77.5 ± 8.2 via SPFS (p = 0.007, Cohen's d = 0.11) in the seated position, and 66.5 ± 9.2 via ECG and 67.8 ± 9.1 via SPFS (p < 0.001, Cohen's d = 0.15) in the standing positions. The SPFS showed a possibly strong correlation to the ECG in all three positions (r values from 0.98 to 0.99). In addition, the limits of agreement (CE ± 1.98 SD) were -0.13 ± 2.83 for the supine values, -0.94± 3.47 for the seated values, and -1.37 ± 3.56 for the standing values. The results of the study suggest good agreement between the SPFS and ECG for measuring lnRMSSD in supine, seated, and standing positions. Though significant differences were noted between the two methods in the seated and standing positions, the effect sizes were trivial.

  8. Unusual raptor nests around the world

    Science.gov (United States)

    Ellis, D.H.; Craig, T.; Craig, E.; Postupalsky, S.; LaRue, C.T.; Nelson, R.W.; Anderson, D.W.; Henny, C.J.; Watson, J.; Millsap, B.A.; Dawson, J.W.; Cole, K.L.; Martin, E.M.; Margalida, A.; Kung, P.

    2009-01-01

    From surveys in many countries, we report raptors using unusual nesting materials (e.g., paper money, rags, metal, antlers, and large bones) and unusual nesting situations. For example, we documented nests of Steppe Eagles Aquila nipalensis and Upland Buzzards Buteo hemilasius on the ground beside well-traveled roads, Saker Falcon Falco cherrug eyries in attics and a cistern, and Osprey Pandion haliaetus nests on the masts of boats and on a suspended automobile. Other records include a Golden Eagle A. chrysaetos nest 7.0 m in height, believed to be the tallest nest ever described, and, for the same species, we report nesting in rudimentary nests. Some nest sites are within a few meters of known predators or competitors. These unusual observations may be important in revealing the plasticity of a species' behavioral repertoire. ?? 2009 The Raptor Research Foundation, Inc.

  9. HTS SQUID application for measuring the magnetic properties of AISI type 316L(N) steel

    Energy Technology Data Exchange (ETDEWEB)

    Park, D.G. E-mail: dgpark@nanum.kaeri.re.kr; Kim, D.W.; Hong, J.H.; Timofeev, V.P.; Kim, C.G

    2000-06-02

    A portable RF HTS SQUID-based susceptometer was used for small-size magnetized sample testing in weak DC (up to 200 A/m) and AC (up to 4 A/m) magnetic fields. The system resolution for the magnetic moment is of the order of 1.6x10{sup -10} A m{sup 2}. The measured DC susceptibility of a tested sample of Gd{sub 88}La{sub 12} agrees well with the value obtained by using a commercial liquid helium susceptometer. The measured volume susceptibility of AISI type 316L(N) steel increases after fatigue due to the microcrack induced by cyclic stress.

  10. Ln{sub 12}-containing 60-tungstogermanates. Synthesis, structure, luminescence, and magnetic studies

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Kai-Yao; Lin, Zhengguo; Roemer, Isabella; Kortz, Ulrich [Jacobs University, Department of Life Sciences and Chemistry, Bremen (Germany); Bassil, Bassem S. [Jacobs University, Department of Life Sciences and Chemistry, Bremen (Germany); Department of Chemistry, Faculty of Sciences, University of Balamand, Tripoli (Lebanon); Vanhaecht, Stef; Parac-Vogt, Tatjana N. [Department of Chemistry, KU Leuven (Belgium); Saenz de Pipaon, Cristina [Institute of Chemical Research of Catalonia (ICIQ), Tarragona (Spain); Galan-Mascaros, Jose Ramon [Institute of Chemical Research of Catalonia (ICIQ), Tarragona (Spain); Catalan Institution for Research and Advanced Studies (ICREA), Barcelona (Spain); Fan, Linyuan; Cao, Jie [Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic, Conversion Materials, School of Chemistry, Beijing Institute of Technology (China)

    2015-12-07

    A new class of hexameric Ln{sub 12}-containing 60-tungstogermanates, [Na(H{sub 2}O){sub 6} is contained in Eu{sub 12}(OH){sub 12}(H{sub 2}O){sub 18}Ge{sub 2}(GeW{sub 10}O{sub 38}){sub 6}]{sup 39-} (Eu{sub 12}), [Na(H{sub 2}O){sub 6} is contained in Gd{sub 12}(OH){sub 6}(H{sub 2}O){sub 24}Ge(GeW{sub 10}O{sub 38}){sub 6}]{sup 37-} (Gd{sub 12}), and [(H{sub 2}O){sub 6} is contained in Dy{sub 12}(H{sub 2}O){sub 24}(GeW{sub 10}O{sub 38}){sub 6}]{sup 36-} (Dy{sub 12}), comprising six di-Ln-embedded {β(4,11)-GeW_1_0} subunits was prepared by reaction of [α-GeW{sub 9}O{sub 34}]{sup 10-} with Ln{sup III} ions in weakly acidic (pH 5) aqueous medium. Depending on the size of the Ln{sup III} ion, the assemblies feature selective capture of two (for Eu{sub 12}), one (for Gd{sub 12}), or zero (for Dy{sub 12}) extra Ge{sup IV} ions. The selective encapsulation of a cationic sodium hexaaqua complex [Na(H{sub 2}O){sub 6}]{sup +} was observed for Eu{sub 12} and Gd{sub 12}, whereas Dy{sub 12} incorporates a neutral, distorted-octahedral (H{sub 2}O){sub 6} cluster. The three compounds were characterized by single-crystal XRD, ESI-MS, photoluminescence, and magnetic studies. Dy{sub 12} was shown to be a single-molecule magnet. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Primer caso de hemoglobina Köln (codon98 GTG>ATG en Costa Rica

    Directory of Open Access Journals (Sweden)

    Walter Cartín

    2010-03-01

    Full Text Available La exposición a ciertos medicamentos puede provocar anemia hemolítica con presencia de cuerpos de Heinz en sangre periférica. Esta anemia puede presentarse por sobredosis de medicamentos, tanto en individuos sanos como en personas con deficiencias enzimáticas como la glucosa-6-fosfato deshidrogenasa, o en presencia de hemoglobinas inestables. Este reporte muestra un caso de anemia hemolítica con cuerpos de Heinz, debido a la presencia de una hemoglobina inestable, cuyos estudios moleculares y HPLC confirmaron el primer caso descrito de hemoglobina Köln (Val98Met en Costa Rica.

  12. SPECTROSCOPIC PROPERTIES OF THE Ln-Ge COMPLEXES WITH DIETHYLENETRIAMINEPENTAACETIC ACID

    Directory of Open Access Journals (Sweden)

    Sergiy Smola

    2007-06-01

    Full Text Available Four new heteronuclear lanthanide complexes with general formula [Ge(OH(μ-HDTPALnGe(OH (μ-DTPA] (Ln = Sm – Dy were synthesized and subsequently characterized by different physico- chemical methods. The structures of new compounds have been proposed. In considered complexes the 4f-luminescence of three-charged ions of samarium, europium, terbium and dysprosium is realized at UV-excitation. It is noteworthy that it is the first observation of 4f-luminescence in water solutions of heteronuclear f-p-complexes. The comparison of luminescent characteristics of hetero- and homonuclear landthanide complexes is described and discussed as well.

  13. Ultrasound and Microwave Coassisted Synthesis and Luminescent Properties of (Ln = La, Gd; Phosphors

    Directory of Open Access Journals (Sweden)

    Jing Hu

    2013-01-01

    Full Text Available In order to control reaction temperature and reduce processing time, a new method of ultrasound irradiation with microwave heating was used to synthesize (Ln = La, Gd; phosphors at only 80°C in 30 minutes. Their crystal structures and morphologies which have been verified by X-ray diffraction (XRD and scanning electron microscopy (SEM exhibited gradual changes due to the insertion of lanthanide ions (La or Gd in calcium molybdates. Codoping of lanthanum ions ( would enhance the emission intensities that were supported by fluorescent spectrophotometry (FL.

  14. Crystal chemistry and electrical conductivity of Ln{sub 2}Eu{sub 2}O{sub 3}F{sub 6} (Ln: Nd, La)

    Energy Technology Data Exchange (ETDEWEB)

    Takashima, Masayuki [Cooperative Research Center, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507 (Japan)]. E-mail: takashima@matse.fukui-u.ac.jp; Yonezawa, Susumu [Department of Materials Science and Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507 (Japan)]. E-mail: yonezawa@matse.fukui-u.ac.jp; Kim, Jeo-ho [Department of Materials Science and Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507 (Japan)

    2006-02-09

    Binary rare-earth metal oxide fluorides Ln{sub 2}Eu{sub 2}O{sub 3}F{sub 6} were synthesized by the solid-state reaction between 1mol Ln{sub 2}O{sub 3} (Ln: La, Nd) and 2mol EuF{sub 3} at 1000-1200{sup o}C in a highly dry atmosphere. Nd{sub 2}Eu{sub 2}O{sub 3}F{sub 6} exhibits the oxide ion conductivity of 2.0Sm{sup -1} at 500{sup o}C under P{sub O{sub 2}}=0.4Pa, and the transport numbers {tau}O{sup 2-} was 0.9 at a temperature ranging from 500 to 700{sup o}C. X-ray diffraction Rietveld analysis revealed Nd{sub 2}Eu{sub 2}O{sub 3}F{sub 6} was the monoclinic lattice with the crystal parameters a{sub 0}=0.396nm, b{sub 0}=1.13nm, c{sub 0}=0.562nm, b=134.8{sup o}, Z=1. The structures of Nd{sub 2.1}Eu{sub 1.9}O{sub 3}F{sub 6} and La{sub 2}Eu{sub 2}O{sub 3}F{sub 6} were also analyzed as the monoclinic structure (a{sub 0}=0.397nm, b{sub 0}=1.13nm, c{sub 0}=0.561nm, {beta}=135.0{sup o}, Z=1 for Nd{sub 2.1}Eu{sub 1.9}O{sub 3}F{sub 6} and a{sub 0}=0.404nm, b{sub 0}=1.14nm, c{sub 0}=0.574nm, {beta}=135.3{sup o}, Z=1 for La{sub 2}Eu{sub 2}O{sub 3}F{sub 6}). The ionic arrangement was suggested to be not a little disordered in the crystal lattice of Nd{sub 2.1}Eu{sub 1.9}O{sub 3}F{sub 6} and La{sub 2}Eu{sub 2}O{sub 3}F{sub 6} in contrast to that in the Nd{sub 2}Eu{sub 2}O{sub 3}F{sub 6}. The disorder of anionic arrangement in Nd{sub 2.1}Eu{sub 1.9}O{sub 3}F{sub 6} and La{sub 2}Eu{sub 2}O{sub 3}F{sub 6} lattice was assumed to result in the lower oxide ion conductivity Nd{sub 2.1}Eu{sub 1.9}O{sub 3}F{sub 6} ({sigma}=1.0Sm{sup -1}, {tau}O{sup 2-}=0.9) and La{sub 2}Eu{sub 2}O{sub 3}F{sub 6} ({sigma}=0.8Sm{sup -1}, {tau}O{sup 2-}=0.7)

  15. Type II lepra reaction: an unusual presentation.

    Science.gov (United States)

    Chauhan, S; D'Cruz, S; Mohan, H; Singh, R; Ram, J; Sachdev, A

    2006-01-27

    Ulcers with maculo-papular rash are an unusual presenting feature of leprosy. They occur as result of neuropathy, type-2 lepra reaction or Lucio's phenomenon. The hall mark of type-2 reaction is erythema nodosum. Very rarely it manifests as ulcerative skin lesions. We describe one such unusual case of a young male who presented with multiple ulcers and maculo-papular rash over the legs, chest and abdomen. In addition to this, he had fever, heart murmur, pulmonary infiltrates, neuropathy, and deranged liver function. A clinical differential diagnosis of infective endocarditis and systemic nectrozing vasculitis was made. Skin biopsy showed dense inflammation with lepra bacilli consistent with type-2 lepra reaction.

  16. An Unusual Bone Loss Around Implants

    Directory of Open Access Journals (Sweden)

    Amirreza Rokn

    2013-01-01

    Full Text Available AbstractPre-implant disease is an inflammatory process, which can affect the surrounding tissues of a functional Osseointegrated implant that is usually as a result of a disequilibrium between the micro-flora and the body defense system.This case reports a 57 years old male with unusual bone loss around dental implants.This was an unusual case of peri-implantitis which occurred only in the implants on one side of the mouth although they all were unloaded implants.

  17. Structural Study of a Doubly Ordered Perovskite Family NaLnCoWO6 (Ln = Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb): Hybrid Improper Ferroelectricity in Nine New Members.

    Science.gov (United States)

    Zuo, Peng; Colin, Claire V; Klein, Holger; Bordet, Pierre; Suard, Emmanuelle; Elkaim, Erik; Darie, Céline

    2017-07-17

    The compounds of the doubly ordered perovskite family NaLnCoWO6 (Ln = Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, and Yb) were synthesized by solid-state reaction, nine of which (Ln = Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, and Yb) are new phases prepared under high-temperature and high-pressure conditions. Their structural properties were investigated at room temperature by synchrotron X-ray powder diffraction and neutron powder diffraction. All of them crystallize in monoclinic structures, especially the nine new compounds have the polar space group P21 symmetry, as confirmed by second harmonic generation measurements. The P21 polar structures were decomposed and refined in terms of symmetry modes, demonstrating that the polar mode is induced by two nonpolar modes in a manner of Hybrid Improper Ferroelectricity. The amplitudes of these three major modes all increase with decreasing the Ln cation size. The spontaneous ferroelectric polarization is estimated from the neutron diffraction data of three samples (Ln = Y, Tb, and Ho) and can be as large as ∼20 μC/cm(2).

  18. Family of defect-dicubane Ni4Ln2 (Ln = Gd, Tb, Dy, Ho) and Ni4Y2 complexes: rare Tb(III) and Ho(III) examples showing SMM behavior.

    Science.gov (United States)

    Zhao, Lang; Wu, Jianfeng; Ke, Hongshan; Tang, Jinkui

    2014-04-07

    Reactions of Ln(III) perchlorate (Ln = Gd, Tb, Dy, and Ho), NiCl2·6H2O, and a polydentate Schiff base resulted in the assembly of novel isostructural hexanuclear Ni4Ln2 complexes [Ln = Gd (1), Tb (2), Dy (3), Ho (4)] with an unprecedented 3d-4f metal topology consisting of two defect-dicubane units. The corresponding Ni4Y2 (5) complex containing diamagnetic Y(III) atoms was also isolated to assist the magnetic studies. Interestingly, complexes 2 and 3 exhibit SMM characteristics and 4 shows slow relaxation of the magnetization. The absence of frequency-dependent in-phase and out-of-phase signals for the Ni-Y species suggests that the Ln ions' contribution to the slow relaxation must be effectual as previously observed in other Ni-Dy samples. However, the observation of χ″ signals with zero dc field for the Ni-Tb and Ni-Ho derivatives is notable. Indeed, this is the first time that such a behavior is observed in the Ni-Tb and Ni-Ho complexes.

  19. Dopant-induced modification of active site structure and surface bonding mode for high-performance nanocatalysts: CO oxidation on capping-free (110)-oriented CeO2:Ln (Ln = La-Lu) nanowires.

    Science.gov (United States)

    Ke, Jun; Xiao, Jia-Wen; Zhu, Wei; Liu, Haichao; Si, Rui; Zhang, Ya-Wen; Yan, Chun-Hua

    2013-10-09

    Active center engineering at atomic level is a grand challenge for catalyst design and optimization in many industrial catalytic processes. Exploring new strategies to delicately tailor the structures of active centers and bonding modes of surface reactive intermediates for nanocatalysts is crucial to high-efficiency nanocatalysis that bridges heterogeneous and homogeneous catalysis. Here we demonstrate a robust approach to tune the CO oxidation activity over CeO2 nanowires (NWs) through the modulation of the local structure and surface state around Ln(Ce)' defect centers by doping other lanthanides (Ln), based on the continuous variation of the ionic radius of lanthanide dopants caused by the lanthanide contraction. Homogeneously doped (110)-oriented CeO2:Ln NWs with no residual capping agents were synthesized by controlling the redox chemistry of Ce(III)/Ce(IV) in a mild hydrothermal process. The CO oxidation reactivity over CeO2:Ln NWs was dependent on the Ln dopants, and the reactivity reached the maximum in turnover rates over Nd-doped samples. On the basis of the results obtained from combined experimentations and density functional theory simulations, the decisive factors of the modulation effect along the lanthanide dopant series were deduced as surface oxygen release capability and the bonding configuration of the surface adsorbed species (i.e., carbonates and bicarbonates) formed during catalytic process, which resulted in the existence of an optimal doping effect from the lanthanide with moderate ionic radius.

  20. A series of noncentrosymmetric antimony sulfides Ln{sub 8}Sb{sub 2}S{sub 15} (Ln = La, Pr, Nd) - syntheses, crystal and electronic structures, and NLO properties

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hua-Jun [Laboratory of Applied Research on the Characteristic Resources in the North of Guizhou Province, School of Chemistry and Chemical Engineering, Zunyi Normal College, Guizhou (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou (China); Zhou, Liu-Jiang [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou (China)

    2015-02-15

    A series of noncentrosymmetric sulfides Ln{sub 8}Sb{sub 2}S{sub 15} (Ln = La, Pr, Nd) were prepared from stoichiometric mixtures of the elements at 1223 K in an evacuated silica tube. The compounds Ln{sub 8}Sb{sub 2}S{sub 15} with Ln = La and Nd are isostructural to Pr{sub 8}Sb{sub 2}S{sub 15} and crystallize in the tetragonal noncentrosymmetric space group I4{sub 1}cd. Their structure contains discrete [SbS{sub 3}]{sup 3-} trigonal pyramids separated by Ln{sup 3+} cations and S{sup 2-} anions. La{sub 8}Sb{sub 2}S{sub 15} shows second harmonic generation with intensities 1.2 times that of the commercially used IR NLO (nonlinear optics) material AgGaS{sub 2} (at 2.05 μm laser). It exhibits excellent thermal stability up to 663 C. Studies with UV/Vis-NIR diffuse reflectance spectroscopy show that La{sub 8}Sb{sub 2}S{sub 15} has an optical gap of around 2.3 eV, and a DFT study indicates a direct band gap with an electronic transfer excitation of S 3p electrons to a La 5d orbital. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. LN206井P110油管的腐蚀原因%Corrosion Reason of P110 Tubing Used in LN206 Well

    Institute of Scientific and Technical Information of China (English)

    毛学强; 谢俊峰; 宋文文; 周怀光; 赵密锋; 陈洪

    2013-01-01

    Severe corrosion occurred at thread joint between submersible pump and spill valve of P110 in LN206 well tubing after 43 days service.The reason of the corrosion failure was studied by metallographic examination,chemical composition analysis,and electrochemical test.The results indicated that to the tubing material,no abnormal phase was found according to micro-morphology observation chemical composition met the requirement of API Spec 5CT.The surface damage was observed on the thread,so the corrosive medium go into the crevice at the damage area.The electrochemical test results show that the potential difference between oil well tubing and spill valve is approximately 110 mV.It is concluded that the corrosion was mainly caused by crevice corrosion,galvanic corrosion,and the high concentration of Cl-accelerated the corrosion process.It is suggested to avoid thread damage during joining the oil well tubing and spill valve.It is necessary thread grease to fully fill the crevice between oil well tubing and spill valve avoid the direct contact of dissimilar metals with significant potential difference.%LN206井中P110油管与潜油泵出口处连接泄油阀的丝扣仅使用了43 d就发生严重腐蚀,对其进行了金相、化学分析和腐蚀电位测试.结果表明,油管的金相组织无异常,化学成分符合API Spec 5CT要求;且油管与泄油阀连接的丝扣有损伤现象,存在一定的缝隙,高浓度的Cl促进了腐蚀;油管的铬含量与泄油阀的相差较大,油管与泄油阀间的电位相差约110mV,电偶腐蚀加速丝扣处腐蚀.建议上扣时避免油管与泄油阀两者连接的丝扣发生损伤,并在丝扣上涂抹质量好的螺纹脂将两者丝扣间的缝隙填满,避免电位相差较大的异种材质直接连接.

  2. Unusual Threshold Anomaly in the 6Li+208Pb System

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chun-Lei; JIA Hui-Ming; WU Zhen-Dong; XU Xin-Xing; BAI Chun-Lin; ZHANG Huan-Qiao; LIN Cheng-Jian; RUAN Ming; LIU Zu-Hua; YANG Feng; WU Xiu-Kun; ZHOU Ping; AN Guang-Peng

    2006-01-01

    @@ The angular distributions of elastic scattering for the 6Li +208Pb system have been measured at several energies around the Coulomb barrier. The parameters of optical potential are extracted by means of a phenomenological optical model analysis. It is found that the real and imaginal potentials show a pronounced energy dependence.The behaviour of the potential at the nearly especially sub-barrier energies in the 6Li+208Pb system is quite different from the results of some previous reports observed in other systems, such as 19 F +208 Pb and 16 O+208 Pb.This unusual threshold phenomenon indicates that breakup channel is strongly coupled with the elastic channel and has obvious effects on optical potential.

  3. Unusual cases of foreign bodies in air passage in children.

    Science.gov (United States)

    Hathiram, B T; Grewal, D S; Pathan, S K; Chandrakiran, C; Gaikwad, N; Joshi, V; Bhargava, P

    1999-08-01

    Tracheobronchial foreign bodies when not treated promptly continue to be a source of morbidity and mortality specially in the paediatric population. Chevaliar Jackson, through meticulous analysis of mechanical problems related to foreign bodies in the air and food passages and their solution, created a science of rehearsed and tested instrumental techniques for their extraction (Jackson and Jackson, 1936). They developed instruments to achieve remarkable results with an almost unbelievably low morbidity and mortality.Aspiration of foreign bodies is seen more commonly in the paediatric age group and nearly 94% of them occur in infants and children (Holinger and Holinger, 1978). According to Jackson, nearly 90% of these foreign body accidents are due to carelessness, and are therefore avoidable. We present two unusual cases of inorganic foreign bodies in the air passages in children with special reference to the problems encountered in their diagnosis and management.

  4. Multilobed mesiodens: a supernumerary tooth with unusual morphology.

    Science.gov (United States)

    Dave, Bhavna; Patel, Jalark; Swadas, Milan; Mallikarjuna, Rachappa

    2013-02-06

    An 8-year-old boy came with a chief complaint of an abnormally shaped tooth situated in upper front teeth region. On examination a supernumerary tooth with multiple lobes was present palatally to the maxillary right permanent central incisor. The morphology of the tooth crown was found to be unusual due to the presence of five lobes in the crown portion. Because of the supernumerary tooth, the permanent right central incisor was displaced labially. Radiographic examination showed a completely formed supernumerary tooth with dilacerated root. On the basis of clinical and radiographic examination, the supernumerary tooth was diagnosed as multilobed mesiodens. Since patient expressed dissatisfaction with the presence of supernumerary tooth, it was decided to extract this mesiodens followed by orthodontic treatment for alignment of labially placed maxillary right permanent central incisor.

  5. Laurus nobilis leaf extract mediated green synthesis of ZnO nanoparticles: Characterization and biomedical applications.

    Science.gov (United States)

    Vijayakumar, Sekar; Vaseeharan, Baskaralingam; Malaikozhundan, Balasubramanian; Shobiya, Malaikkarasu

    2016-12-01

    The present study reports the green synthesis of zinc oxide nanoparticles using the aqueous leaf extract of Laurus nobilis (Ln-ZnO NPs) by co-precipitation method. The synthesized Ln-ZnO NPs were characterized by UV-Vis spectroscopy, FTIR, XRD, TEM, SEM and EDX. Ln-ZnO NPs were crystalline in nature, flower like and have hexagonal wurtzite structure with a mean particle size of 47.27nm. The antibacterial activity of Ln-ZnO NPs was greater against Gram positive (Staphylococcus aureus) bacteria than Gram negative (Pseudomonas aeruginosa) bacteria. The zone of inhibition against S. aureus was 11.4, 12.6 and 14.2mm at 25, 50 and 75μgmL(-1). The zone of inhibition against P. aeruginosa was 9.8, 10.2 and 11.3mm at 25, 50 and 75μgmL(-1). The light and confocal laser scanning microscopic images evidenced that Ln-ZnO NPs effectively inhibited the biofilm growth of S. aureus and P. aeruginosa at 75μgmL(-1). The cytotoxicity studies revealed that Ln-ZnO NPs showed no effect on normal murine RAW264.7 macrophage cells. On the other hand, Ln-ZnO NPs were effective in inhibiting the viability of human A549 lung cancer cells at higher concentrations of 80μgmL(-1). The morphological changes in the Ln-ZnO NPs treated A549 lung cancer cells were observed under phase contrast microscope.

  6. Synergistic Extraction of Lanthanides by 1-Nitroso-2-Naphthol and Trioctylphosphine Oxide in Paraffin Wax

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The paraffin wax was used as a diluent for 1-nitroso-2-naphthol(HA) and trioctylphosphine oxide(TOPO) in the extraction of lanthanides at 70℃. The composition of the extracted species was given as LnA3(TOPO)2 by means of the slope analysis. The variation of the synergistic extraction equilibrium constant(Ksex) was investigated at 60~80℃, and the thermodynamic data were calculated. The dependence of separation factors on temperature was also studied.

  7. Kontinuální měření kvality páry

    OpenAIRE

    Rageh, Akram

    2014-01-01

    Diplomová práce se zabývá měřením, analýzou a následným nalezením vhodných fyzikálních parametrů pro analýzu kvality syté sterilizační páry. Tato práce si klade za cíl určit, kritické parametry systému vyvíječe páry pro provoz dle norem ČSN. Dílčí částí projektu je popis fyzikální sterilizace, syté páry, metod a senzorů pro kontrolu sterilizační páry. The diploma thesis deals with the measurement, analysis, and then finding the appropriate physical parameters for analyzing the quality of s...

  8. Kramers non-magnetic superconductivity in LnNiAsO superconductors.

    Science.gov (United States)

    Li, Yuke; Luo, Yongkang; Li, Lin; Chen, Bin; Xu, Xiaofeng; Dai, Jianhui; Yang, Xiaojun; Zhang, Li; Cao, Guanghan; Xu, Zhu-an

    2014-10-22

    We investigated a series of nickel-based oxyarsenides LnNiAsO (Ln=La, Ce, Pr, Nd, Sm) compounds. CeNiAsO undergoes two successive anti-ferromagnetic transitions at TN1=9.3 K and TN2=7.3 K; SmNiAsO becomes an anti-ferromagnet below TN≃3.5 K; NdNiAsO keeps paramagnetic down to 2 K but orders anti-ferromagnetically below TN≃1.3 K. Superconductivity was observed only in Kramers non-magnetic LaNiAsO and PrNiAsO with Tc=2.7 K and 0.93 K, respectively. The superconductivity of PrNiAsO is further studied by upper critical field and specific heat measurements, which reveal that PrNiAsO is a weakly coupled Kramers non-magnetic superconductor. Our work confirms that the nickel-based oxyarsenide superconductors are substantially different in mechanism to iron-based ones, and are likely to be described by the conventional superconductivity theory.

  9. Highly-efficient multi-watt Yb:CaLnAlO4 microchip lasers

    Science.gov (United States)

    Loiko, Pavel; Serres, Josep Maria; Mateos, Xavier; Xu, Xiaodong; Xu, Jun; Yumashev, Konstantin; Griebner, Uwe; Petrov, Valentin; Aguiló, Magdalena; Díaz, Francesc; Major, Arkady

    2017-02-01

    Tetragonal rare-earth calcium aluminates, CaLnAlO4 where Ln = Gd or Y (CALGO and CALYO, respectively), are attractive laser crystal hosts due to their locally disordered structure and high thermal conductivity. In the present work, we report on highly-efficient power-scalable microchip lasers based on 8 at.% Yb:CALGO and 3 at.% Yb:CALYO crystals grown by the Czochralski method. Pumped by an InGaAs laser diode at 978 nm, the 6 mm-long Yb:CALGO microchip laser generated 7.79 W at 1057-1065 nm with a slope efficiency of η = 84% (with respect to the absorbed pump power) and an optical-to-optical efficiency of ηopt = 49%. The 3 mm-long Yb:CALYO microchip laser generated 5.06 W at 1048-1056 nm corresponding to η = 91% and ηopt = 32%. Both lasers produced linearly polarized output (σ- polarization) with an almost circular beam profile and beam quality factors M2 x,y <1.1. The output performance of the developed lasers was modeled yielding a loss coefficient as low as 0.004-0.007 cm-1. The results indicate that the Yb3+- doped calcium aluminates are very promising candidates for high-peak-power passively Q-switched microchip lasers.

  10. Damage structure of austenitic stainless steel 316LN irradiated at low temperature in HFIR

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, N.; Robertson, J.P.; Grossbeck, M.L.; Rowcliffe, A.F. [Oak Ridge National Lab., TN (United States); Wakai, E. [Japan Atomic Energy Research Inst. (Japan)

    1998-03-01

    TEM disk specimens of austenitic stainless steel 316LN irradiated to damage levels of about 3 dpa at irradiation temperatures of either about 90 C or 250 C have been investigated by using transmission electron microscopy. The irradiation at 90 C and 250 C induced a dislocation loop density of 3.5 {times} 10{sup 22} m{sup {minus}3} and 6.5 {times} 10{sup 22} m{sup {minus}3}, a black dot density of 2.2 {times} 10{sup 23} m{sup {minus}3} and 1.6 {times} 10{sup 23} m{sup {minus}3}, respectively, in the steels, and a high density (<1 {times} 10{sup 22} m{sup {minus}3}) of precipitates in matrix. Cavities could be observed in the specimens after the irradiation. It is suggested that the dislocation loops, the black dots, and the precipitates cause irradiation hardening, an increase in the yield strength and a decrease in the uniform elongation, in the 316LN steel irradiated at low temperature.

  11. ln-Timişoara Molecular Activity Combined Models toward Interspecies Toxicity Assessment

    Science.gov (United States)

    Chicu, Sergiu A.; Putz, Mihai V.

    2009-01-01

    Aiming to provide a unified picture of computed activity – quantitative structure activity relationships, the so called Köln (ESIP-ElementSpecificInfluenceParameter) model for activity and Timisoara (Spectral-SAR) formulation of QSAR were pooled in order to assess the toxicity modeling and inter-toxicity correlation maps for aquatic organisms against paradigmatic organic compounds. The Köln ESIP model for estimation of a compound toxicity is based on the experimental measurement expressing the direct action of chemicals on the organism Hydractinia echinata so that the structural influence parameters are reflected by the metamorphosis degree itself. As such, the calculation of the structural parameters is absolutely necessary for correct evaluation and interpretation of the evolution of M(easured) and the C(computed) values. On the other hand, the Timişoara Spectral-SAR analysis offers correlation models and paths for H.e. species as well as for four other different organisms with which the toxicity may be inter-changed by means of the same mechanism of action induced by certain common chemicals. PMID:20057956

  12. The Uncommon Channel-Based Ln-MOFs for Highly Selective Fe(3+) Detection and Superior Rhodamine B Adsorption.

    Science.gov (United States)

    Xing, Shanghua; Bing, Qiming; Song, Lifei; Li, Guanghua; Liu, Jingyao; Shi, Zhan; Feng, Shouhua; Xu, Ruren

    2016-11-02

    Two new isostructural 3D lanthanide-organic frameworks [H2 N(Me)2 ] [Ln3 (OH)(bpt)3 (H2 O)3 ] (DMF)2 ⋅(H2 O)4 (1-Ln; Ln=Sm and Eu) with a 1D channel (25 Å) have been successfully assembled from the rare trinuclear [Ln3 (OH)(COO)9 ] clusters and biphenyl-3,4',5-tricarboxylic acid (H3 bpt) and exhibit high stability towards water in the pH range 3-10. MOF 1-Eu is a promising luminescent probe for sensing Fe(3+) in aqueous solution and is also selective towards rhodamine B (RhB) with a superior adsorption capacity of 735 mg g(-1) , which is the highest among the reported Ln-MOFs for RhB removal so far. Periodic DFT calculations further confirmed the selective adsorption of rhodamine B over other dyes. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Thermal decomposition of heavy rare-earth butanoates, Ln(C3H7CO2)3 (Ln = Er, Tm, Yb and Lu) in argon

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude; Yue, Zhao; Tang, Xiao

    2016-01-01

    The thermal behaviour of Ln(C3H7CO2)3 (Ln = Er, Tm, Yb or Lu) was studied in argon from room temperature by means of thermogravimetry and differential thermal analysis up to 1400 °C, by infrared spectroscopy, hot-stage optical microscopy and X-ray diffraction. Melting prior to decomposition...... was observed in all four compounds, but its course depends on the rare-earth element. Decomposition to sesquioxides proceeds via the formation of dioxymonocarbonates (Ln2O2CO3) and release of 4-heptanone (C3H7COC3H7) as well as carbon dioxide (CO2) without evidence for an intermediate oxobutanoate stage...

  14. Unicentric Castleman disease at an unusual site

    Directory of Open Access Journals (Sweden)

    Sunita Bamanikar

    2014-01-01

    Full Text Available We report a rare case of unicentric Castleman disease (UCD in a 56-year-old lady, presenting as a soft-tissue mass in an unusual site - mid-dorsal aspect of the arm. She was otherwise asymptomatic. Excision biopsy confirmed the diagnosis. The probable etiological factors, clinical and morphological types, and histological diagnosis are discussed.

  15. Heartworm disease in dogs: unusual clinical cases.

    Science.gov (United States)

    Venco, L; Kramer, L; Genchi, Claudio

    2005-10-24

    Two unusual cases of heartworm infection are described, including one of spontaneous rupture of cardiac chambers, most likely due to the progressive increase in pressure within the right ventricle caused by Dirofilaria immitis infection. Another case report describes persistent left cranial vena cava, which interfered with the surgical removal of heartworm via the left jugular vein.

  16. Unusual cause of pyopericardium with tamponade

    OpenAIRE

    Gowrinath K; Phani Krishna B; Raghavendra C; Sai Ravi Shankar A

    2015-01-01

    Acute pyopericardium due to tuberculosis is uncommon even in high prevalence countries. We report an unusual case of acute pyopericardium with cardiac tamponade complicating tuberculosis pneumonia of lingula in an adult. Prompt catheter drainage of pyopericardium under echocardiographic guidance and six month course of anti-tuberculosis treatment resulted in complete recovery without any sequelae during the follow-up period of ten months.

  17. Unusual cause of neonatal intestinal obstruction | Zikavska ...

    African Journals Online (AJOL)

    Unusual cause of neonatal intestinal obstruction. ... In some cases, diagnosis can be made prenatally but in others manifestation occurs after birth. The aim of this article is to ... Stenosis may result from extrinsic or intrinsic factors. It arises from ...

  18. Meckel's cave tuberculoma with unusual infratemporal extension.

    Science.gov (United States)

    Kesavadas, Chandrasekharan; Somasundaram, S; Rao, Ravi M; Radhakrishnan, V V

    2007-07-01

    The authors describe a rare case of intracranial tuberculoma of the Meckel's cave and cavernous sinus with extension into the infratemporal fossa causing widening of the foramen ovale and adjacent bone destruction. The rarity of the lesion and the unusual extension of the lesion are presented with a brief review of literature.

  19. Unusual presentations of Comamonas kerstersii infection

    Directory of Open Access Journals (Sweden)

    M. Almuzara

    2017-09-01

    Full Text Available The association of Comamonas kerstersii with peritonitis resulting from the presence of perforated appendix has previously been described by our research team. In the present study, we describe the isolation of this microorganism from two forms of unusual presentations of C. kerstersii infection not previously described in the literature: localized intra-abdominal infection (psoas abscess and pelvic peritonitis.

  20. Unusual causes of intrahepatic cholestatic liver disease

    Institute of Scientific and Technical Information of China (English)

    Elias E Mazokopakis; John A Papadakis; Diamantis P Kofteridis

    2007-01-01

    We report five cases with unusual causes of intrahepatic cholestasis,including consumption of Teucrium polium (family Lamiaceae) in the form of tea,Stauffer's syndrome,treatment with tamoxifen citrate for breast cancer,infection with Coxiella Burnetii (acute Q fever),and infection with Brucella melitensis (acute brucellosis).

  1. Granuloma faciale: An unusual diascopic finding

    Directory of Open Access Journals (Sweden)

    Shilpashree P Ravikiran

    2016-01-01

    Full Text Available Granuloma faciale (GF is a benign, chronic inflammatory disorder, characterized by reddish brown plaques with prominent follicular orificesand telangeictasia, usually occurring over the face. The condition often presents a problem in differential diagnosis. Herein we describe a case of GF with an unusual diascopic finding of an apple jelly appearance on diascopy.

  2. An Unusual Case Report of Erupted Odontoma

    Directory of Open Access Journals (Sweden)

    Dhaval Mehta

    2013-01-01

    Full Text Available Odontomas are the most common of the odontogenic tumors of the jaws, which are benign, slow growing, and nonaggressive. They are usually asymptomatic and found in routine dental radiographic examination. Odontomas are usually associated with tooth eruption disturbances. Eruption of odontoma in oral cavity is rare entity. Here we report a case of an unusual erupted compound odontoma.

  3. [Focal epithelial hyperplasia. An unusual clinical aspect].

    Science.gov (United States)

    Bodokh, I; Lacour, J P; Rainero, C; Orth, G; Perrin, C; Hoffman, P; Santini, J; Ortonne, J P

    1993-01-01

    We report a case of focal epithelial hyperplasia in a child born in France of Algerian parents. The clinical appearance was unusual in that certain lesions were verrucous and pediculate. A virological study revealed the presence of papillomavirus 32, one of the two types of HPV specifically associated with this entity.

  4. An unusual cause of suicidal ideations

    Science.gov (United States)

    Landau, Daniel; Stockton, Shannon

    2015-01-01

    While the differential for suicidal ideations is broad, it is known that pathologic brain issues are a cause. Here, a case is presented of a gentleman who had an unusual growth into his frontal lobe leading to the suicidal ideations. The fact that he is chronically immunosuppressed likely led to this unique situation. PMID:26421161

  5. Host composition dependent tunable multicolor emission in the single-phase Ba2(Ln1-zTbz)(BO3)2Cl:Eu phosphors

    NARCIS (Netherlands)

    Xia, Z.; Zhuang, J.; Meijerink, A.; Jing, X.

    2013-01-01

    A new strategy based on the host composition design has been adopted to obtain efficient color-tunable emission from Ba2Ln0.97−zTbz(BO3)2Cl:0.03Eu (Ln = Y, Gd and Lu, z = 0–0.97) phosphors. This study reveals that the single-phase Ba2Ln1−zTbz(BO3)2Cl compounds can be applied to use allowed Eu2+ abso

  6. Enhancement of superconductivity near the pressure-induced semiconductor-metal transition in the BiS₂-based superconductors LnO₀.₅F₀.₅BiS₂ (Ln = La, Ce, Pr, Nd).

    Science.gov (United States)

    Wolowiec, C T; White, B D; Jeon, I; Yazici, D; Huang, K; Maple, M B

    2013-10-23

    Measurements of electrical resistivity were performed between 3 and 300 K at various pressures up to 2.8 GPa on the BiS2-based superconductors LnO0.5F0.5BiS2 (Ln=Pr, Nd). At lower pressures, PrO0.5F0.5BiS2 and NdO0.5F0.5BiS2 exhibit superconductivity with critical temperatures Tc of 3.5 and 3.9 K, respectively. As pressure is increased, both compounds undergo a transition at a pressure Pt from a low Tc superconducting phase to a high Tc superconducting phase in which Tc reaches maximum values of 7.6 and 6.4 K for PrO0.5F0.5BiS2 and NdO0.5F0.5BiS2, respectively. The pressure-induced transition is characterized by a rapid increase in Tc within a small range in pressure of ∼0.3 GPa for both compounds. In the normal state of PrO0.5F0.5BiS2, the transition pressure Pt correlates with the pressure where the suppression of semiconducting behaviour saturates. In the normal state of NdO0.5F0.5BiS2, Pt is coincident with a semiconductor-metal transition. This behaviour is similar to the results recently reported for the LnO0.5F0.5BiS2 (Ln=La, Ce) compounds. We observe that Pt and the size of the jump in Tc between the two superconducting phases both scale with the lanthanide element in LnO0.5F0.5BiS2 (Ln=La, Ce, Pr, Nd).

  7. A new family of [Cu(II)Ln(III)M(V)] heterotrimetallic complexes (Ln = La, Gd, Tb; M = Mo, W): model systems to probe exchange interactions and single-molecule magnet properties.

    Science.gov (United States)

    Visinescu, Diana; Alexandru, Maria-Gabriela; Madalan, Augustin M; Jeon, Ie-Rang; Mathonière, Corine; Clérac, Rodolphe; Andruh, Marius

    2016-05-01

    Four isostructural trinuclear 3d-4f-4(5)d heterotrimetallic complexes, with the general formula [L(2)CuLn(H2O)5(μ-NC)M(CN)7], were obtained from the association of binuclear 3d-4f complexes and {M(V)(CN)8}(3-) metalloligands (M = Mo, Ln = La ; M = W, Ln = La ; M = Mo, Ln = Gd ; M = Mo; Ln = Tb , where H2L(2) = 1,2-ethanediylbis(2-iminomethylene-6-methoxy-phenol)). The metalloligand coordinates through a single-cyanido group at the apical position of the copper(ii) ion belonging to the {Cu(II)Ln(III)} binuclear complex. The analysis of the magnetic data for the La(iii) derivatives (compounds and ), in the 1.85-300 K temperature range, shows a weak ferromagnetic exchange interaction between Cu(II) and Mo(V)/W(V) ions across the cyanido bridge (JCuM/kB = 3.6(6) K; g = 2.23(5) for and JCuM/kB = 3.8(6) K, g = 2.21(5) for , with H = -2JCuMSCu·SM). These results were used to simulate the magnetic properties of compound , using the isotropic spin Hamiltonian H = -2JCuMoSCu·SMo - 2JCuGdSCu·SGd. The resulting magnetic interaction between Cu(II) and Gd(III) ions via the phenoxo-bridge was found to be weakly ferromagnetic (JCuGd/kB = +4.5(2) K with JCuMo/kB = +3.6(2) K, gGd = gCu = 2.00 and gMo = 1.98). The dc magnetic properties for compound also show a predominant ferromagnetic interaction, while the ac magnetic measurements indicate the presence of the slow relaxation of the magnetization below 3.5 K.

  8. Low-Temperature Sintering and Microwave Dielectric Properties of Bi0.9Ln0.05Li0.05V0.9Mo0.1O4 (Ln = Sm, Nd and La) Ceramics

    Science.gov (United States)

    Wang, Zixing; Yuan, Changlai; Yang, Tao; Feng, Qin; Liu, Fei; Chen, Jinman; Zhou, Changrong; Chen, Guohua

    2016-08-01

    Microwave dielectric ceramics of Bi0.9Ln0.05Li0.05V0.9Mo0.1O4 (Ln = Sm, Nd and La) with a low firing temperature were prepared via conventional solid-state reaction. The phases and microstructures of the ceramics were characterized by x-ray diffraction and scanning electron microscopy. The temperature coefficients of resonant frequency in the three compositions increased as sintering temperature increased. It is worth noting that a phase transition of the Bi0.9Ln0.05Li0.05V0.9Mo0.1O4 (Ln = Sm, Nd and La) ceramics from a monoclinic to a tetragonal scheelite structure was found with an increase in sintering temperature. The densification temperatures of all compositions were below 700°C. Excellent microwave dielectric properties were obtained for the Bi0.9Nd0.05Li0.05V0.9Mo0.1O4 ceramic sintered at 650°C, with a dielectric constant of ~72.2, a quality factor of ~6467 GHz and a temperature coefficient of resonant frequency of ~2.6 ppm/°C. The Bi0.9Ln0.05Li0.05V0.9Mo0.1O4 (Ln = Sm, Nd and La) ceramics are chemically compatible with both Ag and Cu powders at their sintering temperatures, and are thus a promising candidate for use in LTCC technology applications.

  9. Synthesis and characterization of K{sub 2}Ln{sub 2/3}Ta{sub 2}O{sub 7}·nH{sub 2}O (Ln= La, Pr, Nd), layered tantalates photo catalysts for water splitting

    Energy Technology Data Exchange (ETDEWEB)

    Valencia S, H.; Tavizon, G. [UNAM, Instituto de Quimica, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Pfeiffer, H. [UNAM, Instituto de Investigaciones en Materiales, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Acosta, D. [UNAM, Instituto de Fisica, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Negron M, A., E-mail: hvalencia@utp.edu.co [UNAM, Instituto de Ciencias Nucleares, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico)

    2015-07-01

    Three compounds of the K{sub 2}Ln{sub 2/3}Ta{sub 2}O{sub 7} (Ln = La, Nd, Pr) cation-deficient Ruddlesden-Popper series were prepared by the Pechini (polymeric complex) method. The crystal structures of the hydrated form of these compounds were determined by Rietveld analysis of the X-ray power diffraction data and High Resolution Transmission Electron Microscopy (HRTEM). The samples were also analyzed to determine specific area (Bet), degree of hydration (Thermogravimetric analysis), and photo catalytic activity for hydrogen evolution from water and aqueous methanol solution. (Author)

  10. Solvochemical synthesis and crystal structure of the fluoride-derivatized early lanthanoid(III) ortho-oxidomolybdates(VI) LnF[MoO{sub 4}] (Ln = Ce-Nd)

    Energy Technology Data Exchange (ETDEWEB)

    Schustereit, Tanja; Schleid, Thomas; Hartenbach, Ingo [Institute for Inorganic Chemistry, University of Stuttgart (Germany)

    2014-10-15

    The development of a new solvochemical synthesis route resulted in single crystals of lanthanoid(III) fluoride oxidomolybdates(VI) with the formula LnF[MoO{sub 4}] for the early lanthanoids (Ln = Ce-Nd); to date, these compounds could not be obtained by solid-state reactions. The preparation strategy comprises the dropwise combination of an alkaline aqueous solution containing molybdenum trioxide, sodium hydroxide and sodium fluoride with an acidic aqueous solution of the lanthanoid(III) nitrate. After the purification of the obtained gel, the noncrystalline product has to be dried at 120 C and converted into a crystalline phase by a final thermal treatment for 24 h at 850 C in evacuated silica ampoules. The crystal structure of the lanthanoid(III) fluoride oxidomolybdates(VI) with formula LnF[MoO{sub 4}] (Ln = Ce-Nd) is not isotypic to those for the smaller rare-earth metals. The title compounds crystallize monoclinically in the space group P2{sub 1}/n (a = 703-694, b = 660-653, c = 939-933 pm and β ∼ 106 ) with four formula units per unit cell. The structure contains crystallographically unique Ln{sup 3+} cations, which are surrounded by two F{sup -} and six O{sup 2-} anions to form distorted bicapped trigonal prisms (CN = 8). These polyhedra are fused together by two common edges (e) consisting of two oxide anions to form {sub ∞}{sup 1}{[LnFO"e_4_/_2O"t_2_/_1]"6"-} strands, which are finally condensed through shared fluoride vertices (v) to build up a three-dimensional {sub ∞}{sup 3}{[LnF"v_2_/_2O"e_4_/_2O"t_2_/_1]"6"-} network that still contains terminal (t) oxygen atoms. The Mo{sup 6+} cations reside in the tetrahedral voids of the aforementioned arrangement. This is the fundamental difference compared to the structures of the representatives with the smaller lanthanoids, in which the Mo{sup 6+} cations interconnect anionic {sub ∞}{sup 2}{[LnF"e_2_/_2O"e_4_/_2O"t_2_/_1]"6"-} layers to achieve their tetrahedral oxygen coordination spheres. Vibrational

  11. Site-selective fluorescence spectroscopy investigations of LnPO{sub 4} xenotime ceramics for radioactive waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, A.; Peters, L. [RWTH Aachen Univ. (Germany). Inst. of Crystallography; Holthausen, J.; Neumeier, S. [Forschungszentrum Juelich (Germany); Huittinen, Nina [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes; Loesch, Henry

    2017-06-01

    Europium incorporation in different LnPO{sub 4} (Ln=Tb, Lu and Gd{sub 1-x}Lu{sub x}) phases crystallizing in the xenotime structure was investigated with site-selective TRLFS, PXRD and Rietveld analyses. Based on recorded emission spectra and diffraction patterns, the formation of three different crystal systems (xenotime, anhydrite, and monazite) could be identified. Aging of the ceramic samples and a second sintering step led to an accumulation of europium in the grain boundaries and on the surface.

  12. Bauer-7-en-3{beta}-yl acetate: a major constituent of unusual samples of Brazilian propolis

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Erica Weinstein [Secretaria da Agricultura e Abastecimento, Pindamonhangaba, SP (Brazil). Agencia Paulista de Tecnologia dos Agronegocios; Message, Dejair [Vicosa Univ., MG (Brazil). Inst. de Biociencias. Dept. de Biologia Animal; Negri, Giuseppina; Salatino, Antonio [Sao Paulo Univ., SP (Brazil). Dept. de Botanica

    2006-03-15

    The pentacyclic triterpenoid bauer-7-en-3{beta}-yl acetate was obtained from thloroform extract of an unusual sample of propolis from southeast Brazil with the yield of 7%. The compound was identified by comparison of IR, MS and NMR analysis with published data. (author)

  13. Influence of Heat Treatment on Mercury Cavitation Resistance of Surface Hardened 316LN Stainless Steel

    Energy Technology Data Exchange (ETDEWEB)

    Pawel, Steven J [ORNL; Hsu, Julia [Massachusetts Institute of Technology (MIT)

    2010-11-01

    The cavitation-erosion resistance of carburized 316LN stainless steel was significantly degraded but not destroyed by heat treatment in the temperature range 500-800 C. The heat treatments caused rejection of some carbon from the carburized layer into an amorphous film that formed on each specimen surface. Further, the heat treatments encouraged carbide precipitation and reduced hardness within the carburized layer, but the overall change did not reduce surface hardness fully to the level of untreated material. Heat treatments as short as 10 min at 650 C substantially reduced cavitation-erosion resistance in mercury, while heat treatments at 500 and 800 C were found to be somewhat less detrimental. Overall, the results suggest that modest thermal excursions perhaps the result of a weld made at some distance to the carburized material or a brief stress relief treatment will not render the hardened layer completely ineffective but should be avoided to the greatest extent possible.

  14. Martensitic Transformation during Fatigue Testing of an AISI 301LN Stainless Steel

    Science.gov (United States)

    Mateo, A.; Fargas, G.; Zapata, A.

    2012-02-01

    The plastic deformation accumulated during fatigue testing can induce the transformation of austenite to martensite in metastable austenitic stainless steels. To analyze this issue, a metastable austenitic stainless steel grade AISI 301 LN was studied in two different conditions, i.e. annealed and cold rolled. In the first case, the steel was fully austenitic, whereas cold rolled material had almost 30% of martensite. High cycle fatigue tests at a stress ratio of 0.8 were carried out on flat specimens from both steel conditions. Several characterization techniques, including optical microscopy, X-ray diffraction (XRD) and electron back scattered diffraction (EBSD), were used to detect and quantify the martensite induced by the cyclic deformation.

  15. Corrosion fatigue behaviour of 317LN austenitic stainless steel in phosphoric acid

    Energy Technology Data Exchange (ETDEWEB)

    Onoro, J. [Ingenieria y Ciencia de los Materiales, ETSI Industriales, Universidad Politecnica de Madrid, c/Jose Gutierrez Abascal, 2, 28006 Madrid (Spain)], E-mail: javier.onoro@upm.es

    2009-10-15

    The corrosion fatigue crack-growth behaviour of AISI 317LN stainless steel was evaluated in air and in 85% phosphoric acid at 20 deg. C. Austenitic stainless steels with high molybdenum content have high corrosion resistance and good mechanical properties. However, this increase in the molybdenum content and other elements such as nitrogen can also modify the microstructure. This leads to a modification of its mechanical properties. The corrosion fatigue crack-growth rate was higher in phosphoric acid immersion than in air. Austenitic stainless steels with a fully austenitic microstructure were more ductile, tough, and behave better against corrosion fatigue. The higher resistance to corrosion fatigue was directly associated to its higher resistance to corrosion.

  16. Study of ln s Physics in $\\bar{p}p$ Interactions at the Split Field Magnet

    CERN Multimedia

    2002-01-01

    This experiment uses the Split Field Magnet detector to investigate the low p^t, ``ln~s'', type of interactions that dominate the @*p cross-section. Systematic comparisons will be made to pp interactions. \\\\ \\\\ Specific areas to be studied include elastic scattering in the regions 0.05 $<$ !t! $<$ 0.8 GeV|2 and 0.8 $<$ !t! $<$ 4.0 GeV|2, and the use of a minimum bias trigger to study topological cross-sections, inclusive spectra, and two-body correlations. Some specialized triggers, run simultaneously with the high t elastic scattering trigger, are being studied. Examples are a trigger requiring Cerenkov identification in a limited region of phase space, and a trigger to select diffractively produced events.

  17. Theory of truth degrees of propositions in the logic system L*n

    Institute of Scientific and Technical Information of China (English)

    LI Jun; WANG Guojun

    2006-01-01

    By means of infinite product of uniformly distributed probability spaces of cardinal n the concept of truth degrees of propositions in the n-valued generalized Lukasiewicz propositional logic system L*n is introduced in the present paper. It is proved that the set consisting of truth degrees of all formulas is dense in [0,1], and a general expression of truth degrees of formulas as well as a deduction rule of truth degrees is then obtained. Moreover, similarity degrees among formulas are proposed and a pseudo-metric is defined therefrom on the set of formulas, and hence a possible framework suitable for developing approximate reasoning theory in n-valued generalized Lukasiewicz propositional logic is established.

  18. Unusual Presentation of Primary Sclerosing Cholangitis

    Directory of Open Access Journals (Sweden)

    BC Pineau

    1997-01-01

    Full Text Available A 23-year-old man presenting with acute pancreatitis and autoimmune hemolytic anemia was diagnosed with primary sclerosing cholangitis (PSC without evidence of ulcerative colitis. This constellation of rare associations constitutes a unique mode of presentation of PSC. Within two years he also developed ankylosing spondylitis with sacroiliitis. Disordered immune regulation as a major factor in the mechanism of injury in PSC is supported by its increased association with other immunologically mediated disorders, most notably ulcerative colitis. Autoimmune hemolytic anemia, however, has been reported to be associated with PSC on only two occasions, and ankylosing spondylitis in the absence of ulcerative colitis is also unusual. In addition, the presentation of PSC with acute pancreatitis has rarely been described. This patient presented with several unusual features of PSC.

  19. An unusual foreign body of esophagus

    Directory of Open Access Journals (Sweden)

    Surinder K Singhal

    2010-07-01

    Full Text Available We report a rare case of an unusually long foreign body (Datun impacted in the esophagus of a 56 year-old gentleman. He was literate, without any psychiatric illness and had been using “Neem” (Azadirachta indica stick for cleaning his teeth for the past twenty years. Neem sticks are used for brushing teeth, perhaps one of the earliest and very effective dental care. On closer questioning he revealed his habit of passing the Neem stick into his throat with the aim of cleaning it too while cleaning his teeth. He presented to our emergency early in the morning with this strange long foreign body impacted in his esophagus which was removed successfully using a Jackson’s adult rigid oesophagoscope. We believe this to be the first case of such an unusually long foreign body to be reported in the literature.

  20. Rare and unusual presentation of periorbital xanthelasma

    Directory of Open Access Journals (Sweden)

    Manpreet Juneja

    2016-07-01

    Full Text Available This report presents a sixty year old female with unusual appearance of bilateral xanthelasma palpebrarum of periorbital region. These lesions were approximately 7 cm × 3 cm in dimensions. Patient’s main complaints were aesthetic appearance and hindrance in downward gaze. Considering the size of the lesions surgical excision was planned and the raw area covered with full thickness skin grafts from supra clavicular region. The aesthetic and functional outcome was good. The aim of this case report is to put forward an unusual presentation of xanthelasma, at the same time to keep in mind the surgical excision with full thickness skin grafting as an excellent treatment modality for periorbital xanthelasma palpebrarum especially in large lesions where other modalities have their own limitations.

  1. Thermomechanical and Isothermal Fatigue Behavior of 316LN Stainless Steel with Varying Nitrogen Content

    Science.gov (United States)

    Prasad Reddy, G. V.; Nagesha, A.; Sandhya, R.; Sankaran, S.; Mathew, M. D.; Bhanu Sankara Rao, K.

    2015-02-01

    Thermomechanical (TMF) and isothermal (IF) fatigue behavior of 316LN stainless steel alloyed with 0.07, 0.14, and 0.22 wt pct nitrogen is presented in this manuscript. In the TMF tests with temperature cycling in the range of 573 K to 873 K (300 °C to 600 °C), life decreased with increasing nitrogen content for both in-phase (IP) and out-of-phase (OP) cycling, with a peak at 0.07 wt pct N. In contrast, 0.14 wt pct N yielded maximum life under IF cycling carried out at 873 K (600 °C). Cyclic lives are seen to follow the sequence, IP-TMF < IF < OP-TMF cycling, and it remained same irrespective of the nitrogen content in 316LN SS. Lives under IP-TMF are lower than those in OP cycling by a factor of 2 to 2.5, in spite of the higher cyclic stress response in OP cycling. At all the nitrogen contents in the present study, nitrogen and dynamic strain aging induced slip localization in the form of planar slip bands both in IP and OP-TMF, in comparison to IF deformation wherein complete planar slip mode of deformation is evidenced only at 0.22 wt pct N. In TMF studies, increasing nitrogen content promoted strong slip localization ( i.e., increase in slip band density with a decrease in interband spacing) in combination with high tensile cyclic stresses that marred the beneficial effect of nitrogen content on TMF life.

  2. Correlation between slow magnetic relaxation and the coordination structures of a family of linear trinuclear Zn(II)-Ln(III)-Zn(II) complexes (Ln = Tb, Dy, Ho, Er, Tm and Yb).

    Science.gov (United States)

    Maeda, Moe; Hino, Shiori; Yamashita, Kei; Kataoka, Yumiko; Nakano, Motohiro; Yamamura, Tomoo; Kajiwara, Takashi

    2012-11-28

    Six linear trinuclear [Ln{Zn(L)(AcO)}(2)]BPh(4) complexes (H(2)L denotes the Schiff-base ligand formed by a condensation reaction between ethylenediamine and two equivalents of o-vanillin), including Ln = Tb (1), Dy (2), Ho (3), Er (4), Tm (5) and Yb (6) were synthesized and were confirmed to be isostructural via X-ray crystallographic analyses. The Ln(III) ion in each complex is deca-coordinated by four equatorial oxygen donors from the methoxo groups of the Schiff-base ligands, two oxygen donors from the acetate anions and four axial oxygen donors from the phenoxo groups of the Schiff-base ligands. AC susceptibility measurements, with an oscillating frequency of 10 to 10,000 Hz, revealed that 1, 2, 4 and 6 show slow magnetic relaxation under a 1000 Oe DC bias field, which occurs via a single process, as confirmed by the semi-circular Cole-Cole plots. These complexes are considered to be field-induced single-molecule magnets under these conditions. The presence or absence of the slow magnetic relaxation process is discussed by correlating the characteristic magnetic anisotropy of each Ln(III) ion with the ligand field anisotropy.

  3. Development of electrolyte-supported intermediate-temperature single-chamber solid oxide fuel cells using Ln 0.7Sr 0.3Fe 0.8Co 0.2O 3- δ (Ln = Pr, La, Gd) cathodes

    Science.gov (United States)

    Ruiz de Larramendi, I.; Lamas, D. G.; Cabezas, M. D.; Ruiz de Larramendi, J. I.; Walsöe de Reca, N. E.; Rojo, T.

    Iron-cobalt-based perovskite oxides with general formula Ln 0.7Sr 0.3Fe 0.8Co 0.2O 3- δ (where Ln = La, Pr and Gd) have been investigated for their application as intermediate-temperature cathodes in solid oxide fuel cells (SOFCs). Powdered samples of these materials were synthesized by a novel gel combustion process and then characterized by X-ray powder diffraction (XPD) and scanning electron microscopy (SEM). XPD patterns were satisfactorily indexed with an orthorhombic GdFeO 3-type structure and, for all samples, a mean particle size of less than 1 μm was estimated from the SEM data. Experimental single-chamber SOFCs using with these materials as cathodes and NiO-SDC (samaria-doped ceria) and SDC as anode and electrolyte, respectively, were evaluated at 600 °C in a methane/oxygen mixtures. Peak power densities of 65.4, 48.7 and 46.2 mW cm -2 were obtained for Ag|Ln 0.7Sr 0.3Fe 0.8Co 0.2O 3- δ|SDC|NiO-SDC|Pt cells with Ln = Pr, La and Gd, respectively. The relatively high power density obtained for the Pr compound shows that it could be an interesting material for cathode of single-chamber SOFCs.

  4. Solid state reaction synthesis and optical spectroscopy of ferroelectric (Gd{sub 1-x}Ln{sub x}){sub 2}(MoO{sub 4}){sub 3}; with Ln = Yb or Tm

    Energy Technology Data Exchange (ETDEWEB)

    Lin Zhoubin; Han Xiumei [Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Cientificas, c/Sor Juana Ines de la Cruz 3, 28049 Madrid (Spain); Zaldo, Carlos, E-mail: cezaldo@icmm.csic.e [Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Cientificas, c/Sor Juana Ines de la Cruz 3, 28049 Madrid (Spain)

    2010-03-04

    A solid state synthesis route was used to prepare (Gd{sub 1-x}Ln{sub x}){sub 2}(MoO{sub 4}){sub 3}, Ln = Yb or Tm, compounds with ferroelectric Pba2 crystal structure. It has been observed that this phase is the only one crystallized during 1123 K annealing for x {<=} 0.12 for Yb and x {<=} 0.3 for Tm. Above these concentration limits the simultaneous formation of trihydrated Ln{sub 2}(MoO{sub 4}){sub 3}, Ln = Yb or Tm, is observed. Up to these concentrations Yb and Tm incorporations do not degrade the SHG efficiency. The position of Yb{sup 3+} and Tm{sup 3+} energy levels involved in laser emission processes were determined by 5 K spectroscopy. The 300 K pumping and emission spectral distributions and excited level lifetime have been determined with the purpose of future applications as self-activated periodically poled ferroelectric laser and non-linear media.

  5. Synthesis, structure and ionic conductivity in scheelite type Li0.5Ce0.5−LnMoO4 ( = 0 and 0.25, Ln = Pr, Sm)

    Indian Academy of Sciences (India)

    Dipankar Saha; Giridhar Madras; Aninda J Bhattacharyya; Tayur N Guru Row

    2011-01-01

    Scheelite type solid electrolytes, Li0.5Ce0.5−LnMoO4 ( = 0 and 0.25, Ln = Pr, Sm) have been synthesized using a solid state method. Their structure and ionic conductivity () were obtained by single crystal X-ray diffraction and ac-impedance spectroscopy, respectively. X-ray diffraction studies reveal a space group of 41/ for Li0.5Ce0.5−LnMoO4 ( = 0 and 0.25, Ln = Pr, Sm) scheelite compounds. The unsubstituted Li0.5Ce0.5MoO4 showed lithium ion conductivity ∼ 10−5-10−3 −1cm-1 in the temperature range of 300-700°C ( = 2.5 × 10−3 −1cm-1 at 700°C). The substituted compounds show lower conductivity compared to the unsubstituted compound, with the magnitude of ionic conductivity being two (in the high temperature regime) to one order (in the low temperature regime) lower than the unsubstituted compound. Since these scheelite type structures show significant conductivity, the series of compounds could serve in high temperature lithium battery operations.

  6. Metathesis synthesis, characterization, spectral and photoactivity studies of Ln2/3MoO4 (Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er and Y)

    Institute of Scientific and Technical Information of China (English)

    Radha Velchuri; Suresh Palla; G. Ravi; Naveen Kumar Veldurthi; J.R. Reddy; M. Vithal

    2015-01-01

    Rare earth ortho-oxomolybdates of composition Ln2/3MoO4 (Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er and Y) were prepared by metathesis reaction. All these materials were characterized by powder X-ray diffraction, Fourier transform-infrared spectroscopy (FT-IR) and UV-Vis diffuse reflectance spectra. The Rietveld analysis of all the samples was carried out to obtain the unit cell pa-rameters and reliability factors. All the materials were crystallized in tetragonal lattice withI41/a space group. The infrared spectra of all the samples were characterized by bands due to MoO42– units. The bandgap energies of all the samples were obtained from UV-Vis DRS spectra. The luminescence spectra of Ln2/3MoO4 (Ln=Pr, Eu and Dy) showed characteristic transitions of the rare earth ions. The visible light photocatalytic activity of all the samples was studied against degradation of methylene blue.

  7. Defect Scheelite-Type Lanthanoid(III Ortho-Oxomolybdates(VI Ln0.667[MoO4] (Ln = Ce, Pr, Nd, and Sm and Their Relationship to Zircon and the NaTl-Type Structure

    Directory of Open Access Journals (Sweden)

    Ingo Hartenbach

    2011-12-01

    Full Text Available The rare-earth metal(III ortho-oxomolybdates with the formula Ln0.667[MoO4] (Ln = Ce, Pr, Nd, and Sm and defect scheelite-type structure crystallize in the tetragonal space group I41/a (a = 533–525, c = 1183–1158 pm with four formula units per unit cell. The Ln3+ cations at Wyckoff position 4b exhibit a coordination sphere of eight oxygen atoms in the shape of a trigonal dodecahedron. The same site symmetry (.. is observed for the tetrahedral oxomolybdate(VI entities [MoO4]2–, since their central Mo6+ cation is situated at the 4a position. Due to this equal site multiplicity, the lanthanoid(III cations have to be statistically under-occupied to maintain electroneutrality, thus a defect scheelite structure emerges. The partial structure of both the Ln3+ cations and the [MoO4]2– anions (if shrunk to their centers of gravity can be best described as distorted diamond-like arrangements. Therefore, these two interpenetrating partial structures exhibit a similar setup as found in the zircon-type as well as in the NaTl-type structure.

  8. Structural, dielectric and magnetic properties of Ba{sub 3}SrLn{sub 2}Fe{sub 2}Nb{sub 8}O{sub 30} (Ln = La, Nd, Sm) filled tungsten bronze ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wang [Laboratory of Dielectric Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027 (China); Yang, Wen Zhi [Laboratory of Dielectric Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027 (China); Ningbo Branch of China Academy of Ordnance Science, Ningbo, 315103 (China); Liu, Xiao Qiang [Laboratory of Dielectric Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027 (China); Chen, Xiang Ming, E-mail: xmchen59@zju.edu.cn [Laboratory of Dielectric Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027 (China)

    2016-08-05

    Structural, dielectric and magnetic properties have been investigated for Ba{sub 3}SrLn{sub 2}Fe{sub 2}Nb{sub 8}O{sub 30} (Ln = La, Nd, Sm) ceramics. The single phase tetragonal filled tungsten bronze structure in space group P4/mbm is obtained for Ba{sub 3}SrLa{sub 2}Fe{sub 2}Nb{sub 8}O{sub 30}, while such tungsten bronze major phase is determined together with minor amount of secondary phases in Ba{sub 3}SrNd{sub 2}Fe{sub 2}Nb{sub 8}O{sub 30} and Ba{sub 3}SrSm{sub 2}Fe{sub 2}Nb{sub 8}O{sub 30}. The saturated magnetic hysteresis loops with enhanced M{sub r} are obtained in the present ceramics at room temperature comparing to the Ba{sub 4}Ln{sub 2}Fe{sub 2}Nb{sub 8}O{sub 30} (Ln = La, Nd, Sm) ceramics. Meanwhile, the typical relaxor behaviors are determined: a broad dielectric peak with strong frequency dispersion and the peak temperature following well with the Vogel–Fulcher relationship. - Highlights: • The tetragonal filled tungsten bronze structure in space group P4/mbm is obtained. • The typical relaxor behaviors are determined. • The magnetic hysteresis loops with enhanced Mr are obtained at room temperature.

  9. Physicochemical properties of rare earth doped ceria Ce0.9Ln0.1O1.95 (Ln = Nd, Sm, Gd) as an electrolyte material for IT-SOFC/SOEC

    Science.gov (United States)

    Chaubey, Nityanand; Wani, B. N.; Bharadwaj, S. R.; Chattopadhyaya, M. C.

    2013-06-01

    Nanosized crystallites of rare earth doped ceria Ce0.9Ln0.1O1.95 (Ln = Nd, Sm, Gd) a promising electrolyte material for Intermediate Temperature - Solid Oxide Fuel Cells/electrolysis cells have been synthesized by standard ceramic route. Detection of impurities in the samples was done by FTIR spectroscopy. X-ray diffraction studies were used for the determination of phase purity, crystal structure and average crystallite size of the samples. Kinetics involved in phase formation has been discussed. Raman study showed a major band around 465 cm-1 in all the samples, which is attributed to the cubic fluorite structure of ceria. It was also found that for samples Ce0.9Ln0.1O1.95 (Ln = Nd, Sm, Gd) the frequency of F2g shifts to lower value. Electrochemical impedance spectroscopy has been used to measure the ionic conductivity of the samples at elevated temperatures. The Gd doped sample showed the highest grain boundary and total conductivity in comparison to Sm and Nd doped sample. Bulk thermal expansion behavior, sintered densities and micro structural features of the samples have also been studied.

  10. Rethinking Sensitized Luminescence in Lanthanide Coordination Polymers and MOFs: Band Sensitization and Water Enhanced Eu Luminescence in [Ln(C15H9O5)3(H2O)3]n (Ln = Eu, Tb).

    Science.gov (United States)

    Einkauf, Jeffrey D; Kelley, Tanya T; Chan, Benny C; de Lill, Daniel T

    2016-08-15

    A coordination polymer [Ln(C15H9O9)3(H2O)3]n (1-Ln = Eu(III), Tb(III)) assembled from benzophenonedicarboxylate was synthesized and characterized. The organic component is shown to sensitize lanthanide-based emission in both compounds, with quantum yields of 36% (Eu) and 6% (Tb). Luminescence of lanthanide coordination polymers is currently described from a molecular approach. This methodology fails to explain the luminescence of this system. It was found that the band structure of the organic component rather than the molecular triplet state was able to explain the observed luminescence. Deuterated (Ln(C15H9O9)3(D2O)3) and dehydrated (Ln(C15H9O9)3) analogues were also studied. When bound H2O was replaced by D2O, lifetime and emission increased as expected. Upon dehydration, lifetimes increased again, but emission of 1-Eu unexpectedly decreased. This reduction is reasoned through an unprecedented enhancement effect of the compound's luminescence by the OH/OD oscillators in the organic-to-Eu(III) energy transfer process.

  11. Unusual Presentation of Multibacillary Nodular Leprosy

    Science.gov (United States)

    Raut, Shweta; Kanade, Swapna; Nataraj, Gita; Mehta, Preeti

    2017-01-01

    Despite India achieving the goal of elimination of leprosy as a public health problem, leprosy is still being transmitted in India. However, due to decreased clinical suspicion of leprosy and atypical case presentations, such cases may be not be diagnosed. We present a case report of an unusual presentation of multibacillary leprosy which presented as nodular lesions. This case report indicates that atypical presentations of leprosy may be missed out by primary care physicians. PMID:28042219

  12. Unusual Gingival Enlargement: A Rare Case Report

    Directory of Open Access Journals (Sweden)

    Ashutosh Dixit

    2014-01-01

    Full Text Available This is an atypical case report of a 20-year-old male patient who suffered from unusual unilateral, gingival enlargement together with rapidly progressive alveolar bone loss. The enlarged gingiva completely covered his left posterior teeth in both arches. The patient was diagnosed with gingival fibromatosis and aggressive periodontitis based on the clinical, histological, and radiographic findings. The gingival enlargement was treated by conventional gingivectomy under local anaesthesia. The postoperative result was uneventful.

  13. Large Penile Mass With Unusual Benign Histopathology

    Directory of Open Access Journals (Sweden)

    Nate Johnson

    2015-09-01

    Full Text Available Pseudoepitheliomatous hyperplasia is an extremely rare condition presenting as a lesion on the glans penis in older men. Physical exam without biopsy cannot differentiate malignant from nonmalignant growth. We report a case of large penile mass in an elderly male with a history of lichen sclerosis, highly suspicious for malignancy. Subsequent surgical removal and biopsy demonstrated pseudoepitheliomatous hyperplasia, an unusual benign histopathologic diagnosis with unclear prognosis. We review the literature and discuss options for treatment and surveillance.

  14. Unusual variant of Cantrell′s pentalogy?

    Directory of Open Access Journals (Sweden)

    Kumar Basant

    2008-01-01

    Full Text Available A 12-hour-old male infant presented with prolapsed abdominal content through a defect on left side of chest wall with respiratory distress. A thorough clinical examination suggested absence of ectopia cordis, abdominal wall defect, and any bony anomaly. The child expired after 6 hours of admission because of respiratory distress and electrolyte imbalance. Is congenital defect of chest wall associated with diaphragmatic hernia without ectopia cordis and omphalocele, an unusual variant of Cantrell′s pentalogy?

  15. Giant intraparenchymal neurocysticercosis: Unusual MRI findings

    Directory of Open Access Journals (Sweden)

    Agarwal Prachi

    2004-04-01

    Full Text Available We report a case of surgically proven giant neurocysticercosis (NCC. MR imaging revealed an unusually large solitary parenchymal cystic lesion showing signal intensity similar to CSF on all pulse sequences, with internal septations and a small nodule in the anterior aspect of this lesion compatible with this diagnosis. Identification of a scolex in a cystic lesion with CSF intensity plays a key role in the diagnosis of NCC. The presence of internal septations is an atypical feature.

  16. Unusual imaging characteristics of complicated hydatid disease

    Energy Technology Data Exchange (ETDEWEB)

    Turgut, Ahmet Tuncay [Department of Radiology, Ankara Training and Research Hospital, Ankara (Turkey)]. E-mail: ahmettuncayturgut@yahoo.com; Altin, Levent [Department of Radiology, Numune Training and Research Hospital, Ankara (Turkey); Topcu, Salih [Department of Thoracic Surgery, Faculty of Medicine, Kocaeli University, Izmit (Turkey); Kilicoglu, Buelent [Department of 4th General Surgery, Ankara Training and Research Hospital, Ankara (Turkey); Altinok, Tamer [Department of Thoracic Surgery, Meram Faculty of Medicine, Selcuk University, Konya (Turkey); Kaptanoglu, Erkan [Department of Neurosurgery, Numune Training and Research Hospital, Ankara (Turkey); Karademir, Alp [Department of Radiology, Numune Training and Research Hospital, Ankara (Turkey); Kosar, Ugur [Department of Radiology, Ankara Training and Research Hospital, Ankara (Turkey)

    2007-07-15

    Hydatid disease, a worldwide zoonosis, is caused by the larval stage of the Echinococcus tapeworm. Although the liver and the lungs are the most frequently involved organs in the body, hydatid cysts of other organs are unusual. Radiologically, they usually demonstrate typical imaging findings, but unusual imaging characteristics of complicated cyst of hydatid disease, associated with high morbidity and mortality, are rarely described in the literature. The purpose of this study is to review the general features of hydatidosis and to discuss atypical imaging characteristics of the complicated hydatid disease in the human, with an emphasis on structure and rupture of the cystic lesion as well as ultrasonography (USG), computed tomography (CT), and magnetic resonance imaging (MRI) features of the disease. In our study, the available literature and images of the cases with complicated hydatidosis involving liver, lung, brain, spine and orbit were reviewed retrospectively. In hydatid disease, there are many potential local and systemic complications due to secondary involvement in almost any anatomic location in humans. Radiologically, in addition to the presence of atypical findings such as perifocal edema, non-homogenous contrast enhancement, multiplicity or septations and calcification, various unusual manifestations due to rupture or infection of the cyst have been observed in our cases with complicated hydatid disease. To prevent subsequent acute catastrophic results and the development of recurrences in various organs, it should be kept in mind that complicated hydatid cysts can cause unusual USG, CT, and MRI findings, in addition to typical ones, in endemic areas. Therefore, familiarity with atypical radiological appearances of complicated hydatid disease may be valuable in making a correct diagnosis and treatment.

  17. An Unusual Cause of Rectal Stenosis

    Directory of Open Access Journals (Sweden)

    Maja Gruber

    2016-08-01

    Full Text Available Solitary rectal ulcer syndrome (SRUS is a benign disease that is often misdiagnosed. It is characterized by a combination of symptoms, endoscopic findings and histology. Patients present with constipation, rectal bleeding, mucous discharge, pain and a sensation of incomplete defecation. There are many different manifestations of this disease, with or without rectal prolapse. We report an unusual presentation of SRUS as a circular stenosis in a middle-aged male.

  18. Probable Unusual Transmission of Zika Virus

    Centers for Disease Control (CDC) Podcasts

    2011-05-23

    This podcast discusses a study about the probable unusual transmission of Zika Virus Infection from a scientist to his wife, published in the May 2011 issue of Emerging Infectious Diseases. Dr. Brian Foy, Associate Professor at Colorado State University, shares details of this event.  Created: 5/23/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 5/25/2011.

  19. Triple Teeth: Report of an Unusual Case

    OpenAIRE

    Prashant Babaji; M. A. Prasanth; Gowda, Ajith R.; Soumya Ajith; Henston D'Souza; Ashok, K. P.

    2012-01-01

    Fusion or synodontia is a union of two or more than two developing teeth. Commonly fusion occurs between teeth of the same dentition, mixed dentition, or between normal and supernumerary teeth. Fused primary teeth present with several clinical problems like caries, periodontal problem, arch asymmetry, delayed eruption, ectopic eruption of succedaneous teeth, aesthetic, and other complications. This paper presents a rare and unusual case of triple teeth in mandibular primary dentition.

  20. Triple Teeth: Report of an Unusual Case

    Directory of Open Access Journals (Sweden)

    Prashant Babaji

    2012-01-01

    Full Text Available Fusion or synodontia is a union of two or more than two developing teeth. Commonly fusion occurs between teeth of the same dentition, mixed dentition, or between normal and supernumerary teeth. Fused primary teeth present with several clinical problems like caries, periodontal problem, arch asymmetry, delayed eruption, ectopic eruption of succedaneous teeth, aesthetic, and other complications. This paper presents a rare and unusual case of triple teeth in mandibular primary dentition.

  1. Unusual presentation of NOMA: a case report.

    Science.gov (United States)

    Fasola, A O; Obiechina, A E; Arotiba, J T

    2003-12-01

    A case of noma with involvement of other parts of the body from extension and spread of cancrum lesion in the oral cavity and primary herpetic stomatitis in a two-year-old male patient is reported. The possible routes of infection to other parts of the body are discussed. It is expected that this case report will stimulate the awareness of health practitioners to this unusual presentation of cancrum oris.

  2. An unusual presentation of a glomus tumour.

    LENUS (Irish Health Repository)

    Nugent, N

    2011-02-01

    Glomus tumours are benign, soft tissue tumours, usually of fingertips. Classically they present with severe pain, temperature sensitivity and localised tenderness. The diagnosis is often delayed due to sometimes non-specific symptoms and rarity of the disorder. While usually a clinical diagnosis, imaging may be necessary for diagnosis and localisation. We present a case of glomus tumour of the fingertip with an unusual history.

  3. An unusual intramolecular trans-amidation.

    Science.gov (United States)

    Rivera, Heriberto; Dhar, Sachin; La Clair, James J; Tsai, Shiou-Chuan; Burkart, Michael D

    2016-06-23

    Polyketide biosynthesis engages a series of well-timed biosynthetic operations to generate elaborate natural products from simple building blocks. Mimicry of these processes has offered practical means for total synthesis and provided a foundation for reaction discovery. We now report an unusual intramolecular trans-amidation reaction discovered while preparing stabilized probes for the study of actinorhodin biosynthesis. This rapid cyclization event offers insight into the natural cyclization process inherent to the biosynthesis of type II polyketide antibiotics.

  4. An unusual cause of anemia and encephalopathy

    OpenAIRE

    Sanjeev Kumar Sharma; Dharma Choudhary; Anil Handoo; Gaurav Dhamija; Gaurav Kharya; Vipin Khandelwal; Mayank Dhamija; Sweta Kothari

    2015-01-01

    The authors present here an interesting case of recent onset anemia that was associated with an encephalopathy of the unusual cause.Although severe anemia can theoretically result in anemic hypoxia and can then lead to hypoxic encephalopathy, it is not a primary cause of encephalopathy. More frequently anemia can contribute together with other multiple causes of encephalopathy, such as infections, metabolic abnormalities, trauma, hepatic dysfunction, hypertension, toxins.

  5. Unusual variant of Cantrell′s pentalogy?

    OpenAIRE

    Kumar Basant; Sharma S.; Kandpal Deepak; Agrawal L

    2008-01-01

    A 12-hour-old male infant presented with prolapsed abdominal content through a defect on left side of chest wall with respiratory distress. A thorough clinical examination suggested absence of ectopia cordis, abdominal wall defect, and any bony anomaly. The child expired after 6 hours of admission because of respiratory distress and electrolyte imbalance. Is congenital defect of chest wall associated with diaphragmatic hernia without ectopia cordis and omphalocele, an unusual variant of Cantr...

  6. Unusual MRI findings in grey matter heteropia

    Energy Technology Data Exchange (ETDEWEB)

    Soto Ares, G.; Hamon-Kerautret, M.; Leclerc, X.; Pruvo, J.P. [Service de Neuroradiologie, Hopital Roger Salengro, CHRU, Lille (France); Houlette, C. [Service de Radiologie, CHRU, Rouen (France); Godefroy, O. [Service de Neurologie B, CHRU, Lille (France)

    1998-02-01

    We report unusual MRI patterns in patients with grey matter heterotopia. Standard T1- and T2-weighted spin-echo and inversion-recovery sequences were used in 22 patients presenting with seizures or developmental delay. The images were reviewed for signal change surrounding white matter and for atypical size, morphology or topography. We found 10 cases of subependymal heterotopias 11 of focal subcortical heterotopia and of diffuse subcortical heterotopia. On clinical or MRI grounds, 8 cases were considered unusual: 2 of the subependymal type, 2 of focal subcortical heterotopia with white matter abnormalities, 2 of focal subcortical heterotopia with no clinicoradiological correlation 1 of extensive hemispheric subcortical heterotopia and 1 of diffuse subcortical heterotopia confined to the frontal lobe. The classical classification of heterotopia enables easy radiological diagnosis even in cases with unusual patterns. In some cases, heterogeneity and high signal in surrounding white matter can be found. Cortical dysplasia is the most frequent associated malformation. (orig.) With 7 figs., 2 tabs., 10 refs.

  7. Nano-to millisecond lifetime luminescence properties in Ln{sub 2}(WO{sub 4}){sub 3} (Ln = La, Ho, Tm and Eu) microcrystalline powders with different crystal structures

    Energy Technology Data Exchange (ETDEWEB)

    Lahoz, F. [Departamento de Física, Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez, S/N, 38206 La Laguna, Tenerife (Spain); Sabalisck, N.P., E-mail: nanprado@ull.edu.es [Departamento de Física, Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez, S/N, 38206 La Laguna, Tenerife (Spain); Cerdeiras, E.; Mestres, L. [Grup de Química de l' Estat Sòlid, Departament de Química Inorgànica, Universitat de Barcelona, 08028 Barcelona (Spain)

    2015-11-15

    Ln{sub 2}(WO{sub 4}){sub 3} crystals (Ln = La, Ho, Tm, Eu) have been synthesized using the conventional solid-state ceramic technique. X-ray diffraction was employed to identify the crystal structure of the compounds. Depending on the ionic radii of RE{sup 3+}, two different structures are found, α-Eu{sub 2}(WO{sub 4}){sub 3} (modulated scheelite-type) or γ-Sc{sub 2}(WO{sub 4}){sub 3} (phase with negative thermal expansion coefficient). The optical characterization is based on absorption, photoluminescence, excitation and kinetic decay studies. Under UV excitation at the (WO{sub 4}){sup 2−} absorption band, two different behaviors are recorded. La{sub 2}(WO{sub 4}){sub 3} compounds show a broad visible emission band with a nanosecond range decay rate, and no energy transfer (ET) from the (WO{sub 4}){sup 2−} moiety to the lanthanide ion is observed. However, evidences of ET are observed for Ln = Tm, Ho and Eu. In particular, the (WO{sub 4}){sup 2−} → Eu{sup 3+} ET is so high that the fluorescence of the (WO{sub 4}){sup 2−} moiety is almost completely quenched. Consequently, upon UV excitation Eu{sub 2}(WO{sub 4}){sub 3} provides an intense visible emission with a 120 μs day lifetime. Although (WO{sub 4}){sup 2−} → Ln{sup 3+} ET also occurs for Ln = Ho and Tm, the relatively small energy gap between energy levels of these ions avoids any detectable luminescence, which is quenched by multiphonon processes. Moreover, the effect of a structural phase transition in Ho{sub 2}(WO{sub 4}){sub 3} crystals on their luminescence properties is analyzed. The broad range of PL response of Ln{sub 2}(WO{sub 4}){sub 3} under UV excitation both in the spectral position of the emission bands (from UV to visible) as well as in the decay range (from ns to hundreds of μs) shows the tunability of wolframates for scintillator applications. - Highlights: • .A wide range of PL properties were observed in Ln{sub 2}(WO{sub 4}){sub 3} compounds depending on Ln. • The PL

  8. Perovskite-Like Polar Lanthanide Formate Frameworks of [NH2NH3][Ln(HCOO)4] (Ln = Tb-Lu and Y): Synthesis, Structures, Magnetism, and Anisotropic Thermal Expansion.

    Science.gov (United States)

    Zhao, Tian-Meng; Chen, Sa; Shang, Ran; Wang, Bing-Wu; Wang, Zhe-Ming; Gao, Song

    2016-10-17

    A series of isostructural hydrazinium lanthanide (Ln) formate framework compounds of [NH2NH3][Ln(HCOO)4] for Ln(3+) ions from Tb(3+) to Lu(3+) and Y(3+) have been successfully prepared by utilizing NH2NH3(+). The compounds crystallize in orthorhombic polar space group Pca21, with cell parameters at 180 K of a = 18.2526(7)-18.1048(5) Å, b = 6.5815(2)-6.5261(2) Å, c = 7.6362(3)-7.5044(2) Å, and V = 917.33(6)-886.67(4) Å(3), showing the effect of lanthanide contraction. The compounds possess polar perovskite-like structures incorporating the hydrazinium cations in the cavities of the NaCl-like framework, in which the Ln(3+) ions in a bicapped trigonal prism are connected by anti-anti and syn-anti formate groups. The N-H···Oformate hydrogen-bonding interactions are between the hydrazinium cations and the anionic framework. One anti-anti formate group is frustrated by the competitive N-H···Oformate hydrogen-bonding interactions. It thus twists or flips upon warming, resulting in large anisotropic thermal expansion and negative thermal expansion below 180 K. A comparison with the transition metal and magnesium analogues revealed that the structural compactness, tighter binding of the hydrazinium cation by the framework, and symmetrically better match between the framework and ammonium cation for Ln compounds could inhibit the occurrence of phase transition in the series. The IR spectroscopic, thermal, and magnetic properties are investigated.

  9. High-pressure investigations of lanthanoid oxoarsenates. I. Single crystals of scheelite-type Ln[AsO{sub 4}] phases with Ln = La-Nd from monazite-type precursors

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, Sebastian J.; Ledderboge, Florian; Schleid, Thomas [Stuttgart Univ. (Germany). Inst. fuer Anorganische Chemie; Heymann, Gunter; Huppertz, Hubert [Innsbruck Univ. (Austria). Inst. fuer Allgemeine, Anorganische und Theoretische Chemie

    2016-08-01

    Transparent single crystals of the scheelite-type Ln[AsO{sub 4}] phases with Ln = La-Nd are obtained by the pressure-induced monazite-to-scheelite type phase transition in a Walker-type module under high-pressure and high-temperature conditions of 11 GPa at 1100-1300 C. Coinciding with this transition, there is an increase in density and a reduction in molar volume of about 4.5 % for the scheelite-type phases (tetragonal, I4{sub 1}/a) for La[AsO{sub 4}] (a = 516.92(4), c = 1186.1(9) pm), Ce[AsO{sub 4}] (a = 514.60(1), c = 1175.44(2) pm), Pr[AsO{sub 4}] (a = 512.63(4), c = 1168.25(9) pm), and Nd[AsO{sub 4}] (a = 510.46(4), c = 1160.32(11) pm) as compared to the well-known monazite-type phases (monoclinic, P2{sub 1}/n). Surprisingly enough, the scheelite-type oxoarsenates(V) exhibit a lower coordination number for the Ln{sup 3+} cations (CN = 8 versus CN = 8 + 1), whereas the isolated tetrahedral [AsO{sub 4}]{sup 3-} anions (d(As-O) = 168.9-169.3 pm for the scheelites as compared to d(As-O) = 167.1-169.9 pm for the monazites) remain almost unchanged. So the densification must occur because of the loss of two edge-connections of the involved [LnO{sub 8+1}]{sup 15-} polyhedra with the [AsO{sub 4}]{sup 3-} tetrahedra in the monazite- resulting in exclusively vertex connected [LnO{sub 8}]{sup 13-} and [AsO{sub 4}]{sup 3-} units in the scheelite-type structure.

  10. Four-shell polyoxometalates featuring high-nuclearity Ln{sub 26} clusters. Structural transformations of nanoclusters into frameworks triggered by transition-metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhong; Li, Xin-Xiong; Yang, Tao; Cai, Zhen-Wen; Zheng, Shou-Tian [State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fujian (China)

    2017-03-01

    A series of polyoxometalates (POMs) that incorporate the highest-nuclearity Ln clusters that have been observed in such structures to date (Ln{sub 26}, Ln=La and Ce) are described, which exhibit giant multishell configurations (Ln is contained in W{sub 6} is contained in Ln{sub 26} is contained in W{sub 100}). Their structures are remarkably different from known giant POMs that feature multiple Ln ions. In particular, the incorporated Ln-O clusters with a nuclearity of 26 are significantly larger than known high-nuclearity (≤10) Ln-O clusters in POM chemistry. Furthermore, they also contain the largest number of La and Ce centers for any POM reported to date and represent a new kind of rare giant POMs with more than 100 W atoms. Interestingly, the La{sub 26}-containing POM can undergo a single-crystal to single-crystal structural transformation in the presence of various transition-metal ions, such as Cu{sup 2+}, Co{sup 2+}, and Ni{sup 2+}, from an inorganic molecular nanocluster into an inorganic-organic hybrid extended framework that is built from POM building blocks with even higher-nuclearity La{sub 28} clusters bridged by transition-metal complexes. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Boiling phenomenon due to quasi-steadily and rapidly increasing heat inputs in LN 2 and LHe I

    Science.gov (United States)

    Sakurai, A.; Shiotsu, M.; Hata, K.

    Dynamic boiling processes, including the transition from a single-phase non-boiling regime to film boiling caused by exponentially increasing heat inputs, Q 0e t/τ for a wide range of periods and pressures on horizontal wires in LN 2 and LHe I were investigated. The main problem is that there are no active cavities on the wire surfaces for initial boiling in the liquids. The heat transfer processes due to increasing heat inputs with increasing rates ranging from quasi-steady to rapidly increasing ones in LN 2 were classified into three types for the pressures. The dynamic boiling processes in LHe I due to rapidly increasing heat inputs at the pressures tested here correspond to Type 3 processes including semi-direct transitions in LN 2 at pressures higher than about 1 MPa. The lower limit temperatures of boiling initiation on the wire surfaces for initial boiling in liquids at pressures due to quasi-steadily increasing heat inputs are clearly lower than the homogeneous spontaneous nucleation temperatures corresponding to these pressures. Liquid superheat close to the solid surface in LHe I was evaluated from the value of the wire surface temperature, taking off the temperature drop due to Kapitza resistance. The initial boiling temperatures due to quasi-steady heat inputs at pressures in saturated LN 2 and LHe I agreed with the values derived from the theoretical model based on the heterogeneous spontaneous nucleation in flooded cavities on the solid surface.

  12. Effect of simvastatin on expression of IL17, HMGB1 and TLR4 in LN kidney tissues of rats

    Institute of Scientific and Technical Information of China (English)

    Ying Qin; Ya-Ting Sun; Lin-Xia Xia; Ying-Jie Zhang; Xue-Jun Yang

    2014-01-01

    Objective:To observe the intervention influence and effect of simvastatin on the expression of interleukin17(LI17), high mobility group protein1(HMGB1) andTLR4 path inLupus nephritis (LN) rats.Methods:A total of28BSXSB male mice withLN(16 weeks) were randomly divided into observation group and the comparison group, observation group was given6 mg•kg-1•d-1 simvastatin in0.1%PBS lavage for4 weeks, the comparison group was not given any treatment. Blood urea nitrogen(BUN) level and urine trace albumin(Scr) level of two groups were determined. The expression ofIL17,HMGB1 andTLR4 protein was detected using immune histochemical method, and the kidney histological damage was observed.Results:BNU,LI17,HMGB1,TLR4 protein andHMGB1 mRNA in observation group was significantly lower than that in control group (P0.05).Histological observation showed glomerular lesions integral of observation group was obviously lower than that of control group.Conclusions:Simvastatin can reduce the expression ofIL17,HMGB1 and TLR4 protein inLN mice, thereby can inhibit the autoimmune response as a potential treatment function ofLN.

  13. Design Guidelines for Collaboration and Participation with Examples from the LN4LD (Learning Network for Learning Design)

    NARCIS (Netherlands)

    Burgos, Daniel; Hummel, Hans; Tattersall, Colin; Brouns, Francis; Koper, Rob

    2007-01-01

    Burgos, D., Hummel, H. G. K., Tattersall, C., Brouns, F., & Koper, R. (2009). Design Guidelines for Collaboration and Participation with Examples from the LN4LD (Learning Network for Learning Design). In L. Lockyer, S. Bennett, S. Agostinho & B. Harper (Eds.), Handbook of Research on Learning Design

  14. Synthesis and catalytic activity of Ln(III) complexes with an unsymmetrical Schiff base including multi()C = N-groups

    Institute of Scientific and Technical Information of China (English)

    姚克敏; 李宁; 沈联芳

    2003-01-01

    A synthetic method for a new unsymmetrical Schiff base and its Ln (III) complexes including multi C == N- groups is reported. The complexes are characterized by elemental analysis, IR spectra, 1H and 13C NMR, especially 2D-COSY1H, 1H NMR spectra. The general formula of the obtained complexes is [Ln3(TBLY)(NO3)3]@nH2O (Ln = La, n = 3; Ln = Nd, n = 5; Ln = Gd, Dy, Yb, Y, n = 7), whereTBLY = tetraglycol aldehyde-2,4-dihydroxy benzaldehyde bis-lysine Schiff base. In addition, the evidence for existence of C == CH-NH- group is supported bythe AM1 method. The complexes obtained may be used as a catalyst. Conversion rate of 80% with the viscosity-average molecular weight 220000 for the polymerization of methyl methacrylate (MMA) without addition of any cocatalyst has been obtained.

  15. A crystal chemical study on the superconductivity and compressibility of LnFePnO (Pn = P, As) superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Li, Huaiyong, E-mail: huaiyong.lee@gmail.com [School of Materials Science and Engineering, Liaocheng University, Liaocheng 252000 (China); Wu, Zhijian; Zhou, Shihong [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zhang, Siyuan, E-mail: syzhang@ciac.jl.cn [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Pu, Xipeng; Yao, Shujuan; Wang, Xiaoqing; Yin, Jie [School of Materials Science and Engineering, Liaocheng University, Liaocheng 252000 (China)

    2015-05-25

    Graphical abstract: The covalency fraction increases in an order of Ln–O < Ln–Pn < Fe–Pn, which favors the electron transfer from LnO layer to FePn layer, At the same time, the Ln–O bonds have a higher lattice energy density as well as bulk modulus than the Fe–Pn bonds in the compounds. As a result, either doping F{sup −} ions or increase the external pressure leads to an increase in the covalency fraction gradient. This also favors the electron transfer. - Highlights: • Bonding characters of Ln–O, Ln–Pn and Fe–Pn bonds were calculated. • Lattice energy density and bulk modulus of Ln–O bonds are higher than those of Fe–Pn. • Doping F{sup −} ions or increase the external pressure leads to an increase in the covalency gradient. - Abstract: The discovery of superconductivity transition in LnFePnO (Pn = P, As) compounds is of great importance in exploring new superconductors as well as understanding the mechanism. In this paper, the bonding characters in LnFePnO compounds and their relationship to the superconductivity at ambient pressure and under external pressure have been studied. The results show that the covalency of the chemical bonds is in an increased order of Ln–O < Ln–Pn < Fe–Pn, and this order favors the electron transfer from LnO layers to FePn layers. It is also calculated that the LnO layers are less compressible than the FePn layers. Applying an external pressure to the compounds, or doping F{sup −} in O{sup 2−} site will increase the covalency gradient among the layers, and thus lead to a higher superconductivity transition temperature.

  16. A family of acetato-diphenoxo triply bridged dimetallic Zn(II)Ln(III) complexes: SMM behavior and luminescent properties.

    Science.gov (United States)

    Oyarzabal, Itziar; Artetxe, Beñat; Rodríguez-Diéguez, Antonio; García, JoséÁngel; Seco, José Manuel; Colacio, Enrique

    2016-06-21

    Eleven dimetallic Zn(II)-Ln(III) complexes of the general formula [Zn(µ-L)(µ-OAc)Ln(NO3)2]·CH3CN (Ln(III) = Pr (1), Nd (2), Sm (3), Eu (4), Gd (5), Tb (6), Dy (7), Ho (8), Er (9), Tm (10), Yb (11)) have been prepared in a one-pot reaction from the compartmental ligand N,N'-dimethyl-N,N'-bis(2-hydroxy-3-formyl-5-bromo-benzyl)ethylenediamine (H2L). In all these complexes, the Zn(II) ions occupy the internal N2O2 site whereas the Ln(III) ions show preference for the O4 external site. Both metallic ions are bridged by an acetate bridge, giving rise to triple mixed diphenoxido/acetate bridged Zn(II)Ln(III) compounds. The Nd, Dy, Er and Yb complexes exhibit field induced single-ion magnet (SIM) behaviour, with Ueff values ranging from 14.12 to 41.55 K. The Er complex shows two relaxation processes, but only the second relaxation process with an energy barrier of 21.0 K has been characterized. The chromophoric L(2-) ligand is able to act as an "antenna" group, sensitizing the near-infrared (NIR) Nd(III) and Yb(III)-based luminescence in complexes 2 and 11 and therefore, both compounds can be considered as magneto-luminescent materials. In addition, the Sm(III), Eu(III) and Tb(III) derivatives exhibit characteristic emissions in the visible region.

  17. Sulfate Exchange of the Nitrate-Type Layered Hydroxide Nanosheets of Ln2(OH)5NO3· nH2O for Better Dispersed and Multi-color Luminescent Ln2O3 Nanophosphors (Ln = Y0.98RE0.02, RE = Pr, Sm, Eu, Tb, Dy, Ho, Er, and Tm)

    Science.gov (United States)

    Wu, Xiaoli; Liu, Weigang; Li, Ji-Guang; Zhu, Qi; Li, Xiaodong; Sun, Xudong

    2016-07-01

    Through restricting thickness growth by performing coprecipitation at the freezing temperature of ~4 °C, solid-solution nanosheets (up to 5-nm thick) of the Ln2(OH)5NO3· nH2O layered hydroxide (Ln = Y0.98RE0.02; RE = Pr, Sm, Eu, Tb, Dy, Ho, Er, and Tm, respectively) were directly synthesized without performing conventional exfoliation. In situ exchange of the interlayer NO3 - with SO4 2- produced a sulfate derivative [Ln2(OH)5(SO4)0.5· nH2O] of the same layered structure and two-dimensional crystallite morphology but substantially contracted d 002 basal spacing (from ~0.886 to 0.841 nm). The sulfate derivative was systematically compared against its nitrate parent in terms of crystal structure and phase/morphology evolution upon heating. It is shown that the interlayer SO4 2-, owing to its bonding with the hydroxide main layer, significantly raises the decomposition temperature from ~600 to 1000 °C to yield remarkably better dispersed oxide nanopowders via a monoclinic Ln2O2SO4 intermediate. The resultant (Y0.98RE0.02)2O3 nanophosphors were studied for their photoluminescence to show that the emission color, depending on RE3+, spans a wide range in the Commission Internationale de l'Eclairage (CIE) chromaticity diagram, from blue to deep red via green, yellow, orange, and orange red.

  18. Reaction of (CP(2)asterisk-lnH)(2) (ln=Y, La) and CP(2)asterisk-Y(2-C(6)H(4)CH(2)NMe(2)) with esters and amides and molecular-structure of [CP(2)asterisk-Y(mu- ocme=chc(oet)o)](2)

    NARCIS (Netherlands)

    Deelman, B.J; Wierda, F.; Meetsma, A.; Teuben, J.H

    1995-01-01

    The activation of esters and amides by (Cp(2)*LnH)(2) [Ln = Y (1a), Ln = La (1b), Cp*=C(5)Me] and Cp(2)*Y(2-C(6)H(4)CH(2)NMe(2)) (2) is described. Compounds 1a and 1b react with ethyl acetate to form Cp(2)*YOEt (3a) and Cp(2)*LaOEt (30). With 1a and ethyl benzoate a 1:1 mixture of 3a and

  19. Production of unusual fatty acids in rapeseed

    Directory of Open Access Journals (Sweden)

    Roscoe Thomas

    2002-01-01

    Full Text Available Vegetable-derived oils are of interest for industrial applications partly because of the chemical similarity of plant oils to mineral oils but also because of the economic need to reduce overproduction of seed oils for nutritional use. Complex oils can be produced in seeds as a low cost agricultural product based on renewable solar energy that requires less refining and is biodegradable and thus produces less adverse effects on the environment. In addition, biotechnologies have accelerated selection programmes and increased the genetic diversity available for the development of new varieties of oilseeds with specific fatty acid compositions. In the developing oilseed, energy and carbon are stored as lipid under the form of triacylglycerol, that is, a glycerol molecule to which three fatty acids are esterified. Fatty acids comprise a linear chain of carbon atoms, the first of which carries an organic acid group. The chain length and the presence of double bonds determine the properties of the fatty acid which in turn determine the physical and chemical properties of the oil of storage lipids and hence their economic value. In addition to the common C16- and C18-saturated and unsaturated fatty acids of membrane lipids, the seed storage lipids of many plant species contain unusual fatty acids (UFAs which can vary in chain length, in the degree of unsaturation, possess double bonds in unusual positions, or can contain additional functional groups such as hydroxy, epoxy, cyclic and acetylenic groups [1]. These unusual fatty acids are of value as industrial feedstocks and their uses include the production of fuels and lubricants, soap and detergents, paints and varnishes, adhesives and plastics (Figure 1.

  20. Red emitting phosphors of Eu{sup 3+} doped Na{sub 2}Ln{sub 2}Ti{sub 3}O{sub 10} (Ln = Gd, Y) for white light emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Niumiao [National Key Laboratory of Photoelectric Technology and Functional Materials Culture Base in Shaanxi Province, National Photoelectric Technology and Functional Materials & Application of Science and Technology International Cooperation Base, Institute of Photonics & Photon-Technology, Northwest University, Xi’an 710069 (China); Guo, Chongfeng, E-mail: guocf@nwu.edu.cn [National Key Laboratory of Photoelectric Technology and Functional Materials Culture Base in Shaanxi Province, National Photoelectric Technology and Functional Materials & Application of Science and Technology International Cooperation Base, Institute of Photonics & Photon-Technology, Northwest University, Xi’an 710069 (China); Yin, Luqiao; Zhang, Jianhua [Key Laboratory of Advanced Display and System Applications (Shanghai University), Ministry of Education, Shanghai 200072 (China); Wu, Mingmei, E-mail: ceswmm@mail.sysu.edu.cn [School of Chemistry and Chemical Engineering, Sun Yat-Sen University, No. 135, Xingang Xi Road, Guangzhou 510275 (China)

    2015-06-25

    Highlights: • Layered red phosphors Na{sub 2}Ln{sub 2}Ti{sub 3}O{sub 10} (Ln = Gd, Y):Eu{sup 3+} were prepared. • The synthesis parameters of phosphors were optimized. • PL and thermal stability of the samples were investigated. • LED devices were also fabricated including the present red phosphor. - Abstract: A series of Eu{sup 3+} doped Na{sub 2}Ln{sub 2}Ti{sub 3}O{sub 10} (Ln = Gd, Y) red-emitting phosphors for application in ultraviolet based light emitting diodes (LEDs) were successfully synthesized by a modified sol–gel method. Their structure and luminescent properties were characterized by powder X-ray diffraction (XRD), photoluminescence excitation (PLE) and emission (PL) spectra and absorption spectra, according to these results the optimal compositions and synthesis parameters were determined. In addition, the thermal stabilities of the phosphors were investigated according to the temperature-dependent PL spectra. The red and white-LEDs (W-LEDs) comprising the Na{sub 2}Ln{sub 2}Ti{sub 3}O{sub 10}:Eu{sup 3+} (Ln = Gd, Y) red emitting phosphors were fabricated with a near-ultraviolet (n-UV) chip. In comparison with Na{sub 2}Y{sub 1.4}Eu{sub 0.6}Ti{sub 3}O{sub 10}, the Na{sub 2}Gd{sub 0.6}Eu{sub 1.4}Ti{sub 3}O{sub 10} phosphor offers higher brightness, quantum efficiency, and excellent thermal stability. W-LEDs comprising Na{sub 2}Gd{sub 0.6}Eu{sub 1.4}Ti{sub 3}O{sub 10} showed bright white emission with a color rendering index (Ra) of 82, a color temperature of 2151 K, and Commission Internationale de I’Eclairage (CIE) color coordinates of (0.34, 0.37). The phosphor Na{sub 2}Gd{sub 0.6}Eu{sub 1.4}Ti{sub 3}O{sub 10} is more suitable candidate for application in LEDs.

  1. Synthesis, luminescence and photometric characteristics of Ca{sub 0.5}La(MoO{sub 4}){sub 2}:Ln{sup 3+} (Ln = Eu, Tb, Dy) phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, Rajagopalan [Department of Physics, B. S. Abdur Rahman University, Vandalur, Chennai 600048, Tamil Nadu (India); Thirumalai, Jagannathan, E-mail: jthirumalai@bsauniv.ac.in [Department of Physics, B. S. Abdur Rahman University, Vandalur, Chennai 600048, Tamil Nadu (India); Mahalingam, Venkatakrishnan [Department of Physics, B. S. Abdur Rahman University, Vandalur, Chennai 600048, Tamil Nadu (India); Mantha, Srinivas [Department of ECE, SASTRA University, Tirumalaisamudram, Thanjavur 613401 (India); Lavanya, Manthramoorthy [Department of Physics, B. S. Abdur Rahman University, Vandalur, Chennai 600048, Tamil Nadu (India)

    2015-07-15

    Ca{sub 0.5}La(MoO{sub 4}){sub 2}:Ln{sup 3+} phosphors, where Ln = 4, 8, 12, 16, and 20 mol% of Eu, Tb, or Dy, were successfully synthesized by a conventional solid-state reaction method at 900 °C for 3 h. The Ca{sub 0.5}La(MoO{sub 4}){sub 2}:Ln{sup 3+} phosphors exhibit a scheelite tetragonal crystal structure belonging to the I4{sub 1}/a space group. The strong absorption bands seen in Fourier transform infrared (FTIR) spectra confirm that F{sub 2}(ν{sub 3}) modes of vibration are IR active. The photoluminescence(PL) spectra reveal that, under optical excitation, the as-synthesized phosphors show high intensity narrow emission bands in the red (615 nm), and green (545 nm), and yellow (570 nm) regions for samples doped with Eu{sup 3+}, Tb{sup 3+}, and Dy{sup 3+} ions, respectively. The critical concentrations of Eu{sup 3+}, Tb{sup 3+}, and Dy{sup 3+} as dopants in Ca{sub 0.5}La(MoO{sub 4}){sub 2} were found to be 16, 12 and 12 mol%, respectively. Thereafter, concentration quenching effect occurred in the solid solutions. The fluorescence decay times for the major transitions of {sup 5}D{sub 0} → {sup 7}F{sub 2}, {sup 5}D{sub 4} → {sup 7}F{sub 5}, and {sup 4}F{sub 9/2} → {sup 6}H{sub 13/2} were estimated for different doping concentrations of Eu{sup 3+}, Tb{sup 3+}, and Dy{sup 3+} in Ca{sub 0.5}La(MoO{sub 4}){sub 2}, respectively. To determine the color purity and emission quality of the phosphor, photometric parameters such as color chromaticity coordinates, color correlated temperature (CCT), color rendering index (CRI), and luminous efficacy of radiation (LER) were estimated using the spectral energy distribution functions of the Ca{sub 0.5}La(MoO{sub 4}){sub 2}:Ln{sup 3+} phosphors. - Graphical abstract: Display Omitted - Highlights: • Single crystalline ceramic phosphor Ca{sub 0.5}La(MoO{sub 4}){sub 2}:Ln{sup 3+} were successfully synthesized. • The phosphor exhibits scheelite tetragonal crystal structure with space group I41/a. • Luminescence

  2. An unusual cause of obstructive jaundice

    Science.gov (United States)

    Abbara, Aula; Al-Hadithy, Huda; Khan, Shahid; Shorvon, Philip

    2009-01-01

    An 80-year-old Caucasian woman presented with a 3-week history of painless jaundice, pruritis, dark urine and weight loss. Blood analysis demonstrated an obstructive jaundice pattern. A CT scan demonstrated a gas-filled duodenal diverticulum arising from the second part of the duodenum. Once food material was cleared from the diverticulum endoscopically, there was clinical and biochemical improvement. This case demonstrates an unusual cause of obstructive jaundice that has seldom been reported in the literature; once impacted food material was removed from the diverticulum, there was radiological improvement of the patient’s condition. PMID:21686538

  3. Basidiobolus: An unusual cause of lung abscess

    Directory of Open Access Journals (Sweden)

    Chetambath Ravindran

    2010-01-01

    Full Text Available Non-resolving pneumonia leading to lung abscess is always a challenge to the treating physician especially in a diabetic patient. Atypical radiological features of lung abscess should raise the suspicion of unusual organisms. This is a case report of a 42 year old diabetic male presented with features suggestive of lung abscess and multiple target organ damage. Subsequent work up revealed that the etiological agent is a rare fungus - Basidiobolus. To the best of our knowledge this is the first case of Basidiobolus lung abscess reported from India.

  4. An unusual case of idiopathic gingival fibromatosis

    Directory of Open Access Journals (Sweden)

    Vikender S Yadav

    2013-01-01

    Full Text Available Idiopathic gingival fibromatosisis, a condition of undetermined cause can develop as an isolated disorder, but mostly it is associated with some syndrome. It usually begins at the time of eruption of permanent teeth but can develop with the eruption of deciduous dentition and rarely present at birth. This case report describes an unusual case of non-syndromic generalized idiopathic gingival fibromatosis in a 15-year-old male present since birth. Surgical treatment in the form of ledge and wedge procedure with internal bevel gingivectomy was performed. No recurrence of enlargement was seen after 2 years of follow-up.

  5. Odontoameloblastoma: A rare case with unusual presentation

    Directory of Open Access Journals (Sweden)

    Supreet Jain

    2016-01-01

    Full Text Available The odontoameloblastoma (OA, also known as ameloblastic odontoma, is a very rare odontogenic tumor that is similar to ameloblastoma in its locally aggressive behavior. OA includes odontogenic ectomesenchyme in addition to odontogenic epithelium that resembles an ameloblastoma both in structure and in behavior. Its clinical presentation, however, often mimics the more innocuous odontoma, and hence, the recognition of its aggressive nature is commonly only ascertained after its histopathologic diagnosis following enucleation. This paper presents a rare case of OA with unusual clinical and radiological features.

  6. Unusual imaging appearance of unicystic ameloblastoma

    Directory of Open Access Journals (Sweden)

    Lakshmi Kavitha Nadendla

    2012-01-01

    Full Text Available Unicystic ameloblastoma (UA refers to those cystic lesions that show clinical, radiographic, or gross features of a mandibular cyst, but on histologic examination show a typical ameloblastous epithelium lining part of the cystic cavity, with or without luminal and/or mural tumor growth. It accounts for 5-15% of all intraosseous ameloblastomas. We report a case of UA in a 35-year-old female with an unusual large multilocular (tennis racket appearance on the right body of mandible and illustrate the importance and complexity of differential diagnosis with a brief review of recent literature.

  7. An Unusual Case of Gastrointestinal Bleeding

    Directory of Open Access Journals (Sweden)

    Kristin N. Fiorino

    2011-01-01

    Full Text Available A 10-year-old boy presented with a 3-day history of worsening abdominal pain, fever, emesis and melena. Abdominal ultrasound revealed a right upper quadrant mass that was confirmed by computed tomography angiogram (CTA, which showed an 8 cm well-defined retroperitoneal vascular mass. 123Iodine metaiodobenzylguanidine (123MIBG scan indicated uptake only in the abdominal mass. Subsequent biopsy revealed a paraganglioma that was treated with chemotherapy. This case represents an unusual presentation of a paraganglioma associated with gastrointestinal (GI bleeding and highlights the utility of CTA and 123MIBG in evaluation and treatment.

  8. An unusual cause of hypertension in pregnancy.

    Science.gov (United States)

    Vriend, Joris W J; van Montfrans, Gert A; van der Post, Joris A M; Lam, Jan; Mulder, Barbara J M

    2004-01-01

    Aortic coarctation is an unusual cause of hypertension in pregnancy. We report the case of a 34-year-old woman with severe hypertension after surgical repair of aortic coarctation in childhood. An MRI showed a residual stenosis of the aortic arch and a small aneurysm. Pregnant postcoarctectomy patients are at an increased risk for developing hypertension during pregnancy due to residual aortic gradients and abnormal vascular reactivity of the precoarctation vessels. Women after repair of aortic coarctation should be closely monitored for blood pressure during pregnancy.

  9. Hypertrophic lupus vulgaris: an unusual presentation.

    Science.gov (United States)

    Jain, Vijay K; Aggarwal, Kamal; Jain, Sarika; Singh, Sunita

    2009-07-01

    Lupus vulgaris is the most common form of cutaneous tuberculosis occurring in previously sensitized individuals with a high degree of tuberculin sensitivity. Various forms including plaque, ulcerative, hypertrophic, vegetative, papular, and nodular forms have been described. A 30-year-old male patient presented with a very large hypertrophic lupus vulgaris lesion over left side of chest since 22 years. Histopathological examination showed granulomatous infiltration without caseation necrosis. The Mantoux reaction was strongly positive. Hypertrophic lupus vulgaris of such a giant size and that too at an unusual site is extremely rare and hence is being reported.

  10. An Unusual Case of Rapidly Progressive Hyperbilirubinemia

    Directory of Open Access Journals (Sweden)

    Kimberly M. Thornton

    2013-01-01

    Full Text Available We present an unusual case of hyperbilirubinemia with rapid early progression leading to bilirubin encephalopathy in a term neonate. Despite early recognition and intervention, the total serum bilirubin reached a maximum level of 39 mg/dL at 32 hours of life. Prior to an emergent exchange transfusion, the patient’s diagnostic evaluation was significant for Coombs-negative microangiopathic hemolytic anemia and thrombocytopenia. Further testing revealed a deficiency of ADAMTS13 protein, or von Willebrand factor-cleaving protease, a finding diagnostic of congenital thrombotic thrombocytopenic purpura, or Upshaw-Schulman syndrome. This rare disease is often misdiagnosed, especially in the newborn period.

  11. Unusual course of the median nerve

    Directory of Open Access Journals (Sweden)

    Vashishtha K

    2010-12-01

    Full Text Available One extremely unusual observation has been reported in this case report. During dissection of left hand of an adult human cadaver we found median nerve passing through the substance of flexor retinaculum. Median nerve coursed through the entire extent of flexor retinaculum in a fascial canal. No other structure was found along with nerve in the fascial canal. After emerging from the flexor retinaculum median nerve took its usual course in the hand. To the best of our knowledge this kind of variant median nerve course has not been described in published literature.

  12. Unusual duodenal perforation following endoscopic retrograde cholangiopancreatography

    Directory of Open Access Journals (Sweden)

    Martin Kobborg

    2011-02-01

    Full Text Available Perforation is a known but rare complication to Endoscopic retrograde cholangiopancreatography (ERCP with endoscopic sphincterotomy (ES. Most of the perforations are located in the periampullary area due to ES. This report presents an unusual perforation in the third part of the duodenum following ES. The patient an eigthy-sixt-year-old man underwent ERCP with ES. The patient had Magnetic Resonance Cholangio-pancreatography (MRCP and Computerized Tomography (CT verified cholelithiasis and intra- and extrahepatic cholestasis. The perforation was not found under the ERCP procedure but was clinically revealed when the patient developed pneumoscrotum after the procedure. A CT-scan with oral contrast later confirmed the duodenal perforation.

  13. Sporotrichosis in an unusual location - Case report*

    Science.gov (United States)

    Reis, Brisa Dondoni; Cobucci, Fernanda Oliveira; Zacaron, Luciana Helena; D'Acri, Antonio Macedo; Lima, Ricardo Barbosa; Martins, Carlos José

    2015-01-01

    Sporotrichosis is the most common subcutaneous mycosis. It is caused by the dimorphic fungus Sporothrix schenckii, and the infection is usually acquired by traumatic inoculation. We describe a case of sporotrichosis in an uncommon location with an unusual mode of transmission. A 49-year-old female patient who lived in an urban area of Rio de Janeiro presented with involvement of the left ear. No history of contact with soil, plants or animals was elicited. The suspected source of infection was a pair of handmade wooden earrings. The delay in the diagnosis and treatment resulted in higher morbidity, unsightly scarring and loss of ear lobe. PMID:26312682

  14. An Unusual Course of Metastatic Gastroesophageal Cancer

    Directory of Open Access Journals (Sweden)

    William H. Smith

    2015-01-01

    Full Text Available We are reporting on a case of a 41-year-old woman who presented with metastatic gastroesophageal junction cancer and who achieved prolonged survival with a multimodal treatment approach. After initially experiencing robust response to chemotherapy, she was treated for distant recurrence with palliative radiation to the gastrohepatic and supraclavicular lymph nodes and subsequently, given her unusual near-complete response, with reirradiation to the abdomen with curative intent for residual disease. The case presented is unique due to the patient’s atypical treatment course, including technically difficult reirradiation to the abdomen, and the resulting prolonged survival despite metastatic presentation.

  15. An Unusual Case of Hydatid Cyst

    Directory of Open Access Journals (Sweden)

    SA Mirhoseini

    2005-03-01

    Full Text Available Hydatidosis is a parasitic disease in all over the world which is caused by a Cestode (tape worm. Liver, lung, and brain are the most Common involved organs and involvement of muscles and bones is unusual. We report a 32years old man who had low back and radicular leg pain. He had a paravertebral mass with involvement of Spinal column. This patient was operated with differential diagnosis of tumor or hydatid cyst. The final diagnosis was hydatidosis of paravertebral muscles and vertebral column. Keywords: hydatidosis, p aravertebral muscle hydatid cyst, spinal column hydatid cyst

  16. Pleural effusion: An unusual cause and association

    Directory of Open Access Journals (Sweden)

    Alam K Navaz

    2013-01-01

    Full Text Available Filaria has a wide spectrum of presentation. We hereby present a case of Filarial pleural effusion that is a rarity in itself. Filarial lung involvement is usually in the form of tropical pulmonary eosinophilia with pulmonary infiltrates and peripheral eosinophilia, unlike our case where isolated pleural effusion of Filarial etiology was detected. Microfilaria has been isolated from Pleural fluid in very few cases, and ours was one such. Of late, there have been many incidental detections of Filarial parasites from varied anatomical sites in association with malignancy. Even in our case, we had one such unusual association.

  17. Amyloidoma, an Unusual Cause of Fracture

    Directory of Open Access Journals (Sweden)

    Frank Verhoeven

    2014-01-01

    Full Text Available We report a case of a spontaneous hip fracture in a context of dysglobulinemia. The bone histologic examination found amyloidoma. Amyloidoma is an overload pathology and an unusual cause of fracture. In most of the cases, it is associated with myeloma and the difference between bone invasion of myeloma and amyloidoma in an osteolytic radiographic picture is not easy but is of importance because prognosis and treatment may be totally different. Thus, in the context of dysglobulinemia, one must keep in mind that spontaneous bone fracture may be due to amyloidoma with another prognosis.

  18. An unusual presentation of primary sclerosing cholangitis

    Institute of Scientific and Technical Information of China (English)

    Franklin Whitney Goldwire; William E Norris; Jonathan M Koff; Zachary D Goodman; Milton T Smith

    2008-01-01

    This case report describes the unusual presentation of a patient who had findings which were initially suggestive of a type IV choledochal cyst.Her liver biopsy demonstrated biliary cirrhosis.She was treated with endoscopic retrograde cholangiopancreatography and biliary stent exchanges over one year.Her cholangiogram one year later demonstrated resolution of the biliary cystic dilation which led to her initial diagnosis,with beading and stricturing of the hepatic ducts consistent with primary sclerosing cholangitis.Liver-associated enzymes and physical findings also improved.A liver biopsy one year later demonstrated a marked improvement in hepatic fibrosis with no evidence of cirrhosis.

  19. Heptanuclear lanthanide [Ln7] clusters: from blue-emitting solution-stable complexes to hybrid clusters.

    Science.gov (United States)

    Canaj, Angelos B; Tsikalas, George K; Philippidis, Aggelos; Spyros, Apostolos; Milios, Constantinos J

    2014-09-07

    The use of LH3 (2-(β-naphthalideneamino)-2-hydroxymethyl-1-propanol) and aibH (2-amino-isobutyric acid) in 4f chemistry has led to the isolation of eight new isostructural lanthanide complexes. More specifically, the reaction of the corresponding lanthanide nitrate salt with LH3 and aibH in MeOH, under solvothermal conditions in the presence of NEt3, led to the isolation and characterization of seven complexes with the general formulae [Ln(III)7(OH)2(L')9(aib)]·4MeOH (Ln = Gd, ·4MeOH; Tb, ·4MeOH; Dy, ·4MeOH; Ho, ·4MeOH; Er, ·4MeOH; Tm, ·4MeOH; Yb, ·4MeOH L' = the dianion of the Schiff base between naphthalene aldehyde and 2-amino-isobutyric acid). Furthermore, the isostructural Y(III) analogue, cluster [Y(III)7(OH)2(L')9(aib)]·4MeOH (·4MeOH), was synthesized in a similar manner to . The structure of all eight clusters describes a distorted [M(III)6] octahedron which encapsulates a seventh M(III) ion in an off-centre fashion. Dc magnetic susceptibility studies in the 5-300 K range for complexes reveal the presence of dominant antiferromagnetic exchange interactions within the metallic clusters as evidenced by the negative Weiss constant, θ, while ac magnetic susceptibility measurements show temperature and frequency dependent out-of-phase signals for the [Dy(III)7] analogue (·4MeOH), suggesting potential single molecule magnetism character. Furthermore, for complex , simulation of its dc magnetic susceptibility data yielded very weak antiferromagnetic interactions within the metallic centres. Solid-state emission studies for all clusters display ligand-based emission, while extended 1D and 2D NMR studies for ·4MeOH reveal that the species retain their structural integrity in solution. In addition, TGA measurements for , and revealed excellent thermal stability up to 340 °C for the clusters.

  20. Series of isostructural planar lanthanide complexes [Ln(III)4(mu3-OH)2(mdeaH)2(piv)8] with single molecule magnet behavior for the Dy4 analogue.

    Science.gov (United States)

    Abbas, Ghulam; Lan, Yanhua; Kostakis, George E; Wernsdorfer, Wolfgang; Anson, Christopher E; Powell, Annie K

    2010-09-06

    A series of five isostructural tetranuclear lanthanide complexes of formula [Ln(4)(mu(3)-OH)(2)(mdeaH)(2)(piv)(8)], (mdeaH(2) = N-methyldiethanolamine; piv = pivalate; Ln = Tb (1), Dy (2), Ho (3), Er (4), and Tm (5)) have been synthesized and characterized. These clusters have a planar "butterfly" Ln(4) core. Magnetically, the Ln(III) ions are weakly coupled in all cases; the Dy(4) compound 2 shows Single Molecule Magnet (SMM) behavior.

  1. Lanthanides electrolytic extraction from molten fluoride by alloy formation; Extraction electrochimique des lanthanides des milieux de fluorures fondus par formation d'alliages

    Energy Technology Data Exchange (ETDEWEB)

    Nourry, Ch

    2007-10-15

    This work consisted in studying the electrochemical behaviour of some dissolved lanthanides (Gd, Nd, Sm) in LiF-CaF{sub 2} media on inert and reactive cathodes in the 800-920 C temperature range and then to estimate their possible extraction from the melt by reduction on a reactive electrode (Ni, Cu or Ni/Cu). Using electrochemical methods and SEM micrographs, reduction mechanisms and thermodynamic parameters such as standard potential and activity coefficient were determined for the different species in the melt. The Gibbs energies and the reduction mechanisms were determined for LnNi and LnCu compounds. Finally, extractions have been performed on reactive electrodes with very good extraction rate ({>=} 99.7%). (author)

  2. A case of gallstone ileus with an unusual impaction site and spontaneous evacuation

    Directory of Open Access Journals (Sweden)

    Anagnostopoulos G

    2004-01-01

    Full Text Available Gallstone ileus is an unusual cause of colonic obstruction. The formation of a fistula between the gall bladder and the bowel wall may allow a gallstone to enter the intestinal tract. Plain abdominal films, abdominal ultrasound and abdominal computed tomography aid in the diagnosis. Although surgery is the treatment of choice in cases of colonic gallstone ileus, colonoscopic removal of the impacted stone should be attempted. We describe the case of an 85-year-old man who presented with symptoms and signs of large bowel obstruction. Diagnostic evaluation revealed a large gallstone impacted in the sigmoid colon, which is a rather unusual impaction site. Despite our efforts we could not extract the stone endoscopically, mainly due to its large size. Yet, despite its large size, the stone was spontaneously evacuated a few hours later.

  3. Foreign body esophagus in a neonate: Unusual age and unusual presentation

    Directory of Open Access Journals (Sweden)

    Ranju Singh

    2012-01-01

    Full Text Available Foreign body ingestion in neonatal period is an uncommon occurrence, despite foreign ingestion being common among pediatric age group. We report a rare case of foreign body esophagus in a 12-day-old female neonate causing obstructive symptoms after a homicidal attempt. The unusual age and circumstances involving the ingestion of the foreign body prompted us to report this case.

  4. Physicochemical Properties of Near-Linear Lanthanide(II) Bis(silylamide) Complexes (Ln = Sm, Eu, Tm, Yb).

    Science.gov (United States)

    Goodwin, Conrad A P; Chilton, Nicholas F; Vettese, Gianni F; Moreno Pineda, Eufemio; Crowe, Iain F; Ziller, Joseph W; Winpenny, Richard E P; Evans, William J; Mills, David P

    2016-10-17

    Following our report of the first near-linear lanthanide (Ln) complex, [Sm(N(††))2] (1), herein we present the synthesis of [Ln(N(††))2] [N(††) = {N(Si(i)Pr3)2}; Ln = Eu (2), Tm (3), Yb (4)], thus achieving approximate uniaxial geometries for a series of "traditional" Ln(II) ions. Experimental evidence, together with calculations performed on a model of 4, indicates that dispersion forces are important for stabilization of the near-linear geometries of 1-4. The isolation of 3 under a dinitrogen atmosphere is noteworthy, given that "[Tm(N″)(μ-N″)]2" (N″ = {N(SiMe3)2}) has not previously been structurally authenticated and reacts rapidly with N2(g) to give [{Tm(N″)2}2(μ-η(2):η(2)-N2)]. Complexes 1-4 have been characterized as appropriate by single-crystal X-ray diffraction, magnetic measurements, electrochemistry, multinuclear NMR, electron paramagnetic resonance (EPR), and electronic spectroscopy, along with computational methods for 3 and 4. The remarkable geometries of monomeric 1-4 lead to interesting physical properties, which complement and contrast with comparatively well understood dimeric [Ln(N″)(μ-N″)]2 complexes. EPR spectroscopy of 3 shows that the near-linear geometry stabilizes mJ states with oblate spheroid electron density distributions, validating our previous suggestions. Cyclic voltammetry experiments carried out on 1-4 did not yield Ln(II) reduction potentials, so a reactivity study of 1 was performed with selected substrates in order to benchmark the Sm(III) → Sm(II) couple. The separate reactions of 1 with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), azobenzene, and benzophenone gave crystals of [Sm(N(††))2(TEMPO)] (5), [Sm(N(††))2(N2Ph2)] (6), and [Sm(N(††)){μ-OPhC(C6H5)CPh2O-κO,O'}]2 (7), respectively. The isolation of 5-7 shows that the Sm(II) center in 1 is still accessible despite having two bulky N(††) moieties and that the N-donor atoms are able to deviate further from linearity or ligand

  5. An Unusual Case of Acute Epiglottic Abscess

    Directory of Open Access Journals (Sweden)

    Tanthry Deepalakshmi

    2014-01-01

      Incision and drainage was performed under general anaesthesia after haematological investigations. Patient was extubated the next day, and was discharged after two days, also oral antibiotics, and analgesics were prescribed. Patient was reviewed after 2 weeks, and indirect laryngoscopy revealed a normal epiglottis.Although pharyngitis is the most common cause of sore throat in adults, acute epiglottitis must be considered in differential diagnosis when there is unrelenting throat pain, and minimal objective signs of pharyngitis. Epiglottic abscess formation is more common in adults than children. They most commonly occur as a complication of acute pharyngitis or with abscess of lingual tonsil .The abscess most frequently comes to a point on or near the lingual surface of the epiglottis. Streptococcus was isolated more frequently. Other organisms reported were Haemophilus influenzae, E.coli, Pseudomonas, Micro- coccus catarrhalis, Pneumococci. In our case, there were no preceding symptoms of acute pharyngitis. Risk factors include adult age at onset, diabetes mellitus, trauma, presence of a foreign body, and immune- compromised state. This case is unusual because of the absence of above risk factors. Incision and drainage under general anaesthesia is the treatment of choice. To the author’s knowledge, very few cases of acute epiglottic abscesses have been reported in the literature. This case is unusual because there are no preceding symptoms of pharyngitis or tonsillitis, and no association of risk factors like diabetes mellitus, trauma, foreign body or immunocompromised state.

  6. Extensive Air Showers with unusual structure

    Directory of Open Access Journals (Sweden)

    Beznosko Dmitriy

    2017-01-01

    Full Text Available A total of 23500 Extensive Air Showers (EAS with energies above ∼ 1016 eV have been detected during the ∼3500 hours of the Horizon-T (HT detectors system operations before Aug. 2016. Among these EAS, more than a thousand had an unusual spatial and temporary structure that showed pulses with several maxima (modals or modes from several detection points of the HT at the same time. These modes are separated in time from each other starting from tens to thousands of ns. These EAS have been called multi-modal. Analysis shows that the multi-modal EAS that have been detected by Horizon-T have the following properties: 1. Multi-modal EAS have energy above ∼1017 eV. 2. Pulses with several modes are located at large distances from the EAS axis. An overview of the collected data will be provided. General comments about the unusual structure of the multi-modal EAS will be presented.

  7. Unusual case of thiamine responsive megaloblastic anemia.

    Science.gov (United States)

    Tinsa, Faten; Ben Amor, Saadia; Kaabachi, Naziha; Ben Lasouad, Mehdi; Boussetta, Khadija; Bousnina, Souad

    2009-02-01

    Thiamine-responsive megaloblastic anemia syndrome is a rare autosomal recessive disorder defined by the occurrence of megaloblastic anemia, diabetes mellitus, and neurosensoriel deafness, responding in varying degrees to thiamine treatment. Report an unusual case of this rare disorder We report the case of a four-year-old boy who presented unusual features of thiamine-responsive megaloblastic anemia. In addition to the typical triad of the syndrome, he presented leuconeutropenia, hepatosplenomegalia, cardiac abnormalities including absent P waves, mitral and tricuspid insufficiency, retinitis pigmentosa, nystagmus, developmental delay and a brain Magnetic resonance imaging ischemic lesion. Lactate levels in serum and the lactate/pyruvate ratio were increased. The mitochondrial mutation m.3243A > G located in MTTL1 gene encoding for transfer RNA leucine (tRNALeu(UUR)) was not found. Treatment with thiamine resulted in normalisation of the haemoglobin level, white cell count, and glucose and lactate levels. On three years follow up, the patient did not need insulinotherapy. These data sign the crucial role that thiamine plays for many cells and tissues and its importance in the activity of the respiratory chain.

  8. Unusual Dermoid Cyst in Oral Cavity

    Directory of Open Access Journals (Sweden)

    Evanice Menezes Marçal Vieira

    2014-01-01

    Full Text Available Dermoid cysts in oral cavity are unusual lesions. Their etiology is not yet clear and can be associated with trapped cells as a result of the inclusion error resulting in the development into the ectoderm, mesoderm, and endoderm tissues. The aim of this case report is to evidence the presence of a dermoid cyst in the floor of mouth surgically removed. In the present case, the lesion showed soft consistency, floating, regular borders, smooth surface, and the same color as the adjacent mucosa, asymptomatic and measuring 4.5 × 5.5 cm in its greatest diameter. The initial diagnostic was ranula in consequence of the similarity with clinical characteristics and localization. After surgical removal lesion, a fibrotic capsule was identified with a friable material with intensive yellow color. The microscopic exam showed cystic lesion with cavity lined by squamous stratified epithelium hyperorthokeratinized. Cutaneous attachments, such as sebaceous glands and hair follicles, were present in connective adjacent tissue. Surgical intervention is elective in these situations. All dentists must have a thorough knowledge of this unusual lesion.

  9. Unusual Dermoid Cyst in Oral Cavity

    Science.gov (United States)

    Vieira, Evanice Menezes Marçal; Volpato, Luis Evaristo Ricci; Porto, Alessandra Nogueira; Carvalhosa, Artur Aburad; Botelho, Gilberto de Almeida; Bandeca, Matheus Coelho

    2014-01-01

    Dermoid cysts in oral cavity are unusual lesions. Their etiology is not yet clear and can be associated with trapped cells as a result of the inclusion error resulting in the development into the ectoderm, mesoderm, and endoderm tissues. The aim of this case report is to evidence the presence of a dermoid cyst in the floor of mouth surgically removed. In the present case, the lesion showed soft consistency, floating, regular borders, smooth surface, and the same color as the adjacent mucosa, asymptomatic and measuring 4.5 × 5.5 cm in its greatest diameter. The initial diagnostic was ranula in consequence of the similarity with clinical characteristics and localization. After surgical removal lesion, a fibrotic capsule was identified with a friable material with intensive yellow color. The microscopic exam showed cystic lesion with cavity lined by squamous stratified epithelium hyperorthokeratinized. Cutaneous attachments, such as sebaceous glands and hair follicles, were present in connective adjacent tissue. Surgical intervention is elective in these situations. All dentists must have a thorough knowledge of this unusual lesion. PMID:24818032

  10. Z phase stability in AISI 316LN + Nb austenitic steels during creep at 650 C

    Energy Technology Data Exchange (ETDEWEB)

    Vodarek, Vlastimil [Technical Univ. Ostrava (Czech Republic)

    2010-07-01

    The creep resistance of austenitic CrNi(Mo) steels strongly depends on microstructural stability during creep exposure. Nitrogen additions to CrNi(Mo) austenitic steels can significantly improve the creep strength. One of the most successful methods of improving the long-term creep resistance of austenitic steels is based on increasing the extent of precipitation strengthening during creep exposure. The role of precipitates in the achievements of good creep properties has been extensively studied for a long time. Although many minor phases are now well documented there are still contractions and missing thermodynamic data about some minor phases. This contribution deals with results of microstructural studies on the minor phase evolution in wrought AISI 316LN niobium stabilised steels during long-term creep exposure at 650 C. Microstructural investigations were carried out on specimens taken from both heads and gauge lengths of ruptured test-pieces by means of optical metallography, transmission and scanning electron microscopy. The attention has been paid to evaluation of thermodynamic and dimensional stability of Z phase and other nitrogen bearing minor phases. Only two nitrogen-bearing minor phases formed in the casts investigated: Z phase and M{sub 6}X. The dimensional stability of Z phase particles was very high. (orig.)

  11. Optimization of hybrid laser - TIG welding of 316LN steel using response surface methodology (RSM)

    Science.gov (United States)

    Ragavendran, M.; Chandrasekhar, N.; Ravikumar, R.; Saxena, Rajesh; Vasudevan, M.; Bhaduri, A. K.

    2017-07-01

    In the present study, the hybrid laser - TIG welding parameters for welding of 316LN austenitic stainless steel have been investigated by combining a pulsed laser beam with a TIG welding heat source at the weld pool. Laser power, pulse frequency, pulse duration, TIG current were presumed as the welding process parameters whereas weld bead width, weld cross-sectional area and depth of penetration (DOP) were considered as the process responses. Central composite design was used to complete the design matrix and welding experiments were conducted based on the design matrix. Weld bead measurements were then carried out to generate the dataset. Multiple regression models correlating the process parameters with the responses have been developed. The accuracy of the models were found to be good. Then, the desirability approach optimization technique was employed for determining the optimum process parameters to obtain the desired weld bead profile. Validation experiments were then carried out from the determined optimum process parameters. There was good agreement between the predicted and measured values.

  12. Z phase stability in AISI 316LN + Nb austenitic steels during creep at 650 C

    Energy Technology Data Exchange (ETDEWEB)

    Vodarek, Vlastimil [Technical Univ. Ostrava (Czech Republic)

    2010-07-01

    The creep resistance of austenitic CrNi(Mo) steels strongly depends on microstructural stability during creep exposure. Nitrogen additions to CrNi(Mo) austenitic steels can significantly improve the creep strength. One of the most successful methods of improving the long-term creep resistance of austenitic steels is based on increasing the extent of precipitation strengthening during creep exposure. The role of precipitates in the achievements of good creep properties has been extensively studied for a long time. Although many minor phases are now well documented there are still contractions and missing thermodynamic data about some minor phases. This contribution deals with results of microstructural studies on the minor phase evolution in wrought AISI 316LN niobium stabilised steels during long-term creep exposure at 650 C. Microstructural investigations were carried out on specimens taken from both heads and gauge lengths of ruptured test-pieces by means of optical metallography, transmission and scanning electron microscopy. The attention has been paid to evaluation of thermodynamic and dimensional stability of Z phase and other nitrogen bearing minor phases. Only two nitrogen-bearing minor phases formed in the casts investigated: Z phase and M{sub 6}X. The dimensional stability of Z phase particles was very high. (orig.)

  13. Effects of Different Forging Processes on Microstructure Evolution for 316LN Austenitic Stainless Steel

    Science.gov (United States)

    Sui, Dashan; Zhu, Lingling; Wang, Tao; Zhang, Peipei; Cui, Zhenshan

    2017-07-01

    Forging experiments were designed and carried out on a 3150 kN hydraulic press to investigate the effects of different processes on the microstructure evolution for 316LN steel. The forging processes included single-pass (upsetting) and multipass (stretching) deformations, and the experimental results indicated that the average grain size varied with forging processes. Moreover, the size had distinct differences at different positions in the workpiece. Meanwhile, numerical simulations were implemented to study the influence of temperature, strain, and strain rate on microstructure evolution. The results of experiments and simulations comprehensively demonstrated that dynamic, static, and meta-dynamic recrystallization could coexist in the hot forging process and that the recrystallization process could easily occur under the conditions of higher temperature, larger strain, and higher strain rate. Moreover, the temperature had more significant influence on both recrystallization and grain growth. A higher temperature could not only promote the recrystallization but also speed up the grain growth. Therefore, a lower temperature is beneficial to obtain refinement grains on the premise that the recrystallization can occur completely.

  14. Pairing in the BCS and LN approximations using continuum single particle level density

    Science.gov (United States)

    Id Betan, R. M.; Repetto, C. E.

    2017-04-01

    Understanding the properties of drip line nuclei requires to take into account the correlations with the continuum spectrum of energy of the system. This paper has the purpose to show that the continuum single particle level density is a convenient way to consider the pairing correlation in the continuum. Isospin mean-field and isospin pairing strength are used to find the Bardeen-Cooper-Schrieffer (BCS) and Lipkin-Nogami (LN) approximate solutions of the pairing Hamiltonian. Several physical properties of the whole chain of the Tin isotope, as gap parameter, Fermi level, binding energy, and one- and two-neutron separation energies, were calculated and compared with other methods and with experimental data when they exist. It is shown that the use of the continuum single particle level density is an economical way to include explicitly the correlations with the continuum spectrum of energy in large scale mass calculation. It is also shown that the computed properties are in good agreement with experimental data and with more sophisticated treatment of the pairing interaction.

  15. Enhanced mechanical properties of type AISI301LN austenitic stainless steel through advanced thermo mechanical process

    Energy Technology Data Exchange (ETDEWEB)

    Huang Junxia, E-mail: huangjunxia@baosteel.com [Shanghai Baosteel Research Institute, Shanghai 200431 (China); Ye Xiaoning; Gu Jiaqing; Chen Xu [Shanghai Baosteel Research Institute, Shanghai 200431 (China); Xu Zhou [School of Material Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer 69% of strain induced martensite were obtained after 80% thickness reduction at 0 Degree-Sign C. Black-Right-Pointing-Pointer The best annealing regime was determined for diffusional controlled reversion. Black-Right-Pointing-Pointer The effect of grain size on mechanical properties conforms with the H-P relationship. - Abstract: The effect of annealing temperature and time on the grain size of reversed austenite and mechanical properties was studied based on AISI301LN austenitic stainless steel in this paper. Cold rolling at 0 Degree-Sign C was employed to obtain the strain-induced martensite, followed by annealing treatment at the temperature range of 650-900 Degree-Sign C for 1-20 min. The relationship between the volume fraction of strain-induced martensite and cold reduction was analyzed by Ferritescope MP30 and X-ray diffraction. The grain growth of reversed austenite was observed by FEG-SEM and the mechanical properties were determined by tensile tests and Vickers hardness tests. Austenite grain sizes under 3 {mu}m can be obtained after annealing in the range of 700-900 Degree-Sign C for 1-20 min. The finest austenite grain size was produced after annealing at 700 Degree-Sign C for 20 min, which had a good combination of yield strength ( Almost-Equal-To 830 MPa), tensile strength ( Almost-Equal-To 953 MPa) and elongation ( Almost-Equal-To 36%).

  16. Pairing in the BCS and LN approximations using continuum single particle level density

    Energy Technology Data Exchange (ETDEWEB)

    Id Betan, R.M., E-mail: idbetan@ifir-conicet.gov.ar [Instituto de Física Rosario (CONICET-UNR), Bv. 27 de Febrero 210 bis, S2000EZP Rosario (Argentina); Facultad de Ciencias Exactas, Ingeniería y Agrimensura (UNR), Av. Pellegrini 250, S2000BTP Rosario (Argentina); Instituto de Estudios Nucleares y Radiaciones Ionizantes (UNR), Riobamba y Berutti, S2000EKA Rosario (Argentina); Repetto, C.E. [Instituto de Física Rosario (CONICET-UNR), Bv. 27 de Febrero 210 bis, S2000EZP Rosario (Argentina); Facultad de Ciencias Exactas, Ingeniería y Agrimensura (UNR), Av. Pellegrini 250, S2000BTP Rosario (Argentina)

    2017-04-15

    Understanding the properties of drip line nuclei requires to take into account the correlations with the continuum spectrum of energy of the system. This paper has the purpose to show that the continuum single particle level density is a convenient way to consider the pairing correlation in the continuum. Isospin mean-field and isospin pairing strength are used to find the Bardeen–Cooper–Schrieffer (BCS) and Lipkin–Nogami (LN) approximate solutions of the pairing Hamiltonian. Several physical properties of the whole chain of the Tin isotope, as gap parameter, Fermi level, binding energy, and one- and two-neutron separation energies, were calculated and compared with other methods and with experimental data when they exist. It is shown that the use of the continuum single particle level density is an economical way to include explicitly the correlations with the continuum spectrum of energy in large scale mass calculation. It is also shown that the computed properties are in good agreement with experimental data and with more sophisticated treatment of the pairing interaction.

  17. Corrosion Fatigue Behavior of 316LN SS in Acidified Sodium Chloride Solution at Applied Potential

    Science.gov (United States)

    Poonguzhali, A.; Pujar, M. G.; Mallika, C.; Mudali, U. Kamachi

    2015-05-01

    The influence of acidified 1 M NaCl solution by addition of 2 ml/L of HCl on the cyclic plastic deformation of AISI Type 316LN SS containing 0.07 wt.% and 0.22 wt.% N was investigated as a function of the applied potentials. The corrosion fatigue (CF) behavior of stainless steel (SS) was explained vis-a-vis the dislocation behavior, the propensity to form microcracks, and the evolution of the current transients based on the studies carried out at both room-temperature and boiling conditions. CF experiments were conducted using round tensile specimens at a stress ratio of 0.5 and a frequency of 0.1 Hz. Two different kinds of damage mechanisms were observed (I) the damage mechanism in the stable-passive state was correlated with the localization of the anodic dissolution due to a depassivation-repassivation process, whereas (II) the cyclic stress induced pitting corrosion in the metastable pitting state, which resulted in formation of microcracks. The study of the microcracking process and its evolution is a key to the physical mechanism by which the fatigue life of stainless steels would be affected in an aqueous corrosive solution under the applied potential.

  18. Flux of Nitrogen-13 from L-(N-13)Glutamate in isolated myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Keen, R.E.; Barrio, J.R.; Krivokapich, J.; Phelps, M.E.

    1985-05-01

    Specific activity of nitrogen-13 containing metabolites in tissue and effluent was determined following an intra-arterial bolus of non-carrier added L-(N-13)glutamate (N-13 GLU) given to isolated rabbit septa under different metabolic states which include pyruvate (2 mM), transaminase inhibition (aminooxy-acetate, AOA, 2 mM), or pyruvate with AOA superimposed on the insulin and glucose perfused septa. Six minutes after the N-13 GLU bolus administration relative tissue specific activities of glutamine, alanine, aspartate, and glutamate were approximately 3:38:52:100, respectively, in the control and pyruvate perfused septa. The lower alanine specific activity when compared with control tissue indicated that alanine output was from a pool separate from GPT alanine pools. Higher glutamate specific activity suggested that its output is from a pool(s) different than the larger intra-cellular glutamate pool(s). All interventions with AOA blocked N-13 flux through transminases altering tissue and effluent relative specific activities with increase in % N-13 and specific activities for glutamine, glutamate, ammonia, and protein concomittant with disappearance of labeled aspartate and alanine. These results indicate that N-13 distribution in myocardium after N-13 GLU administration is mainly controlled by glutamate interaction with reversible transaminases. The differences in reactant (N-13 GLU) and product specific activities are a consequence of channeling between different cytosolic and mitochondrial glutamate microcompartments.

  19. Hydrothermal synthesis of 4ZnO·B2O3·H2O:Ln(3+) (Ln=Eu, Tb) phosphors: Morphology-tunable and luminescence properties.

    Science.gov (United States)

    Cao, Shiwei; Jiao, Yang; Han, Weifang; Ge, Chunhua; Song, Bo; Wang, Jie; Zhang, Xiangdong

    2017-09-18

    4ZnO·B2O3·H2O:Ln(3+) (Ln=Eu, Tb) phosphors with different morphologies have been successfully synthesized via one-step hydrothermal method through regulating the molar amount of Eu(3+) and Tb(3+). Comprehensive scanning electron microscopy (SEM), X-ray diffraction (XRD) Fourier transform infrared spectrum (FT-IR) and inductively coupled plasma atomic emission spectrometer (ICP-AES) characterizations all confirm that obtained products are 4ZnO·B2O3·H2O:Ln(3+) (Ln=Eu, Tb). The experimental results displayed that the morphology and photoluminescence of compounds is regularly changed with increased the molar amount of rare earth ions. For the Eu(3+)-doped, Tb(3+)-doped and Eu(3+)/Tb(3+) co-doped 4ZnO·B2O3·H2O phosphors of morphologies, the rod-like structures gradually changed to flower-like structures, fine wire-like structure and hybrid structure, respectively. To their photoluminescence, the Eu(3+) shows a red emission (615nm); the Tb(3+) shows a green emission (545nm); for the Eu(3+)/Tb(3+) co-doped 4ZnO·B2O3·H2O phosphors, a combination of blue (5d-4f of Eu(2+)), green ((5)D4-(7)F5 of Tb(3+)) and red ((5)D0-(7)F2 of Eu(3+)) emissions emerges to achieve white emission. In addition, the energy transfer among Eu(3+), Eu(2+) and Tb(3+) ions was also discussed. Copyright © 2017. Published by Elsevier B.V.

  20. Synthesis, Structure, and Physical Properties of Ln(Cu,Al,Ga)13-x (Ln = La-Pr, and Eu) and Eu(Cu,Al)13-x

    Energy Technology Data Exchange (ETDEWEB)

    Phelan, W Adam; Kangas, Michael J; McCandless, Gregory T; Drake, Brenton L; Haldolaarachchige, Neel; Zhao, Liang L; Wang, Jiakui K; Wang, Xiaoping P; Young, David P; Morosan, Emilia; Hoffmann, Christina; Chan, Julia Y [LSU; (Rice); (ORNL)

    2012-09-10

    Ln(Cu,Al,Ga)13–x (Ln = La–Pr, and Eu; x ~ 0.2) were synthesized by a combined Al/Ga flux. Single crystal X-ray and neutron diffraction experiments revealed that these compounds crystallize in the NaZn13 structure-type (space group Fm3⁻c) with lattice parameters of a ~ 12 Å, V ~ 1600 Å, and Z ~ 8. Our final neutron models led us to conclude that Cu is occupationally disordered on the 8b Wyckoff site while Cu, Al, and Ga are substitutionally disordered on the 96i Wyckoff site of this well-known structure-type. The magnetic susceptibility data show that Ce(Cu,Al,Ga)13–x and Pr(Cu,Al,Ga)13–x exhibit paramagnetic behavior down to the lowest temperatures measured while Eu(Cu,Al,Ga)13–x displays ferromagnetic behavior below 6 K. Eu(Cu,Al)13–x was prepared via arc-melting and orders ferromagnetically below 8 K. The magnetocaloric properties of Eu(Cu,Al,Ga)13–x and Eu(Cu,Al)13–x were measured and compared. Additionally, an enhanced value of the Sommerfeld coefficient (γ = 356 mJ/mol-K2) was determined for Pr(Cu,Al,Ga)13–x. Herein, we present the synthesis, structural refinement details, and physical properties of Ln(Cu,Al,Ga)13–x (Ln = La–Pr, and Eu) and Eu(Cu,Al)13–x.

  1. Water Exchange on [Ln(DO3A)(H2O)2] and [Ln(DTTA-Me)(H2O)2](-) Studied by Variable Temperature, Pressure, and Magnetic Field NMR.

    Science.gov (United States)

    Karimi, Shima; Helm, Lothar

    2016-05-02

    Water exchange kinetics of [Ln(L)(H2O)2](x) complexes (Ln = Pr, Nd, Dy, Tm, and Yb; L = DO3A and DTTA-Me) were studied by (17)O NMR spectroscopy as a function of temperature, pressure, and frequency and by (1)H nuclear magnetic relaxation dispersion. Water exchange rate constants of both complexes show a maximum at dysprosium. Water exchange on negatively charged complexes of the acyclic DTTA-Me ligand is much faster than on the neutral complexes of the macrocyclic DO3A. Small activation volumes |ΔV(⧧)| studied. In the case of [Ln(DTTA-Me)(H2O)2](-), a change in mechanism is detected from a dissociative mechanism (D, ΔV(⧧) = 7 cm(3) mol(-1)) for complexes with larger ions (Pr to Gd) to an interchange mechanism (Id, I; ΔV(⧧) = +1.8 and +0.4 cm(3) mol(-1)) for complexes with smaller ions (Dy and Tm).

  2. Lanthanide triangles sandwiched by tetranuclear copper complexes afford a family of hendecanuclear heterometallic complexes [Ln(III)3Cu(II)8] (Ln = La-Lu): synthesis and magnetostructural studies.

    Science.gov (United States)

    Iasco, Olga; Novitchi, Ghenadie; Jeanneau, Erwann; Luneau, Dominique

    2013-08-05

    Reaction in ethanol of 3-hydroxymethylen-5-methylsalicylaldoxime (H3L) with CuCl2·2H2O and LnCl3·xH2O [Ln = La (1), Ce (2), Pr (3), Nd (4), Eu (5), Gd (6), Tb (7), Dy (8), Er (9), Yb (10), Lu (11), Ho (12)] allowed the synthesis of a family of hendecanuclear heterometallic copper(II)-lanthanide(III) clusters with general formula [Ln(III)3Cu(II)8(HL)6(μ4-O)2Cl6(H2O)8]Cl3 (1-12). According to the single-crystal X-ray diffraction investigation, the complexes are isomorphous and crystallize in the trigonal R32 group. The hendecanuclear cluster is formed by two tetrahedral μ4-oxo {Cu4} clusters assembled by three lanthanide ions sandwiched in between. Along the family, the separation between the {Cu4} moieties increases linearly from Lu to La in good correlation with ionic radius of the lanthanide ions. A comparative analysis of the magnetic data for the lanthanum (1) and lutetium (11) compounds shows the presence of ferromagnetic and antiferromagnetic interactions within the μ4-oxo {Cu4} moieties. For the gadolinium (6) and terbium (7) compounds, the magnetic interactions between the lanthanide and the copper ions are found to be ferromagnetic. The dysprosium (8) compound exhibits single-molecule magnet behavior.

  3. Twinned CsLn{sub 2}F{sub 7} compounds (Ln=Nd, Gd, Tb, Er, Yb). The role of a highly symmetrical cation lattice with an arrangement analogous to the Laves phase MgZn{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Friese, Karen [Forschungszentrum Juelich GmbH, Juelich (Germany). Juelich Centre for Neutron Science-2; Khaidukov, Nicholas [Kurnakov Institute of General and Inorganic Chemistry, Moscow (Russian Federation); Grzechnik, Andrzej [RWTH Aachen Univ. (Germany). Inst. for Crystallography

    2016-07-01

    The occurrence of twinning can often be related to higher symmetrical structures. Fluorides are frequently twinned due to their close relation to high symmetry structures like fluoride, tysonite or pyrochlores. The series of compounds CsLn{sub 2}F{sub 7} is no exception. We refined the structures of the twinned compounds with Ln=Nd, Gd, Tb, Er, Yb in space group P112{sub 1}/b. An analysis of the pseudosymmetry of the resulting structures shows a highly symmetrical cation partial structure with a cation distribution similar to the one in the hexagonal Laves phase MgZn{sub 2}. Several other compounds ALn{sub 2}F{sub 7}, which have been described in the literature, show a similar cation array. The diversity of different space groups which have been reported for ALn{sub 2}F{sub 7} compounds can be better understood using group-subgroup relationships assuming the hypothetical structure of the cation array with space group P6{sub 3}/mmc as aristotype. Furthermore, the twinning is easily understood on the basis of the lost symmetry operations in the symmetry reduction from point group 6/mmm, e.g. to 2/m in the case of the CsLn{sub 2}F{sub 7} compounds.

  4. Semi-supervised Adapted HMMs for Unusual Event Detection

    OpenAIRE

    Zhang, Dong; Gatica-Perez, Daniel; Bengio, Samy

    2004-01-01

    We address the problem of temporal unusual event detection. Unusual events are characterized by a number of features (rarity, unexpectedness, and relevance) that limit the application of traditional supervised model-based approaches. We propose a semi-supervised adapted Hidden Markov Model (HMM) framework, in which usual event models are first learned from a large amount of (commonly available) training data, while unusual event models are learned by Bayesian adaptation in an unsupervised man...

  5. Semi-supervised Adapted HMMs for Unusual Event Detection

    OpenAIRE

    Zhang, Dong; Gatica-Perez, Daniel; Bengio, Samy; McCowan, Iain A.

    2005-01-01

    We address the problem of temporal unusual event detection. Unusual events are characterized by a number of features (rarity, unexpectedness, and relevance) that limit the application of traditional supervised model-based approaches. We propose a semi-supervised adapted Hidden Markov Model (HMM) framework, in which usual event models are first learned from a large amount of (commonly available) training data, while unusual event models are learned by Bayesian adaptation in an unsupervised man...

  6. Imaging Unusual Pregnancy Implantations: Rare Ectopic Pregnancies and More.

    Science.gov (United States)

    Dibble, Elizabeth H; Lourenco, Ana P

    2016-12-01

    The purpose of this article is to review key clinical issues and imaging features of unusual pregnancy implantations. Examples from different imaging modalities are provided to increase interpreting physicians' familiarity with the appearance and potential complications of unusual ectopic, cesarean scar, heterotopic, and rudimentary horn pregnancies. Abnormal pregnancy implantations are life-threatening. Interpreting physicians' familiarity with the appearance of unusual pregnancy implantations is critical for early identification and initiation of appropriate therapy.

  7. The structures and luminescence properties of lanthanide (Ln = Sm, Eu and Tb) metal-organic coordination polymers based on 5-(2-hydroxyethoxy)isophthalate ligand

    Science.gov (United States)

    Wang, Peng; Zhang, Yu-Jie; Qin, Jie; Chen, Yong; Zhao, Ying

    2015-03-01

    Three unreported isomorphous Ln-containing metal-organic coordination polymeric complexes {LnL(HL)ṡ(H2O)2}n (Ln = Sm (1), Eu (2) and Tb (3), CCDC 971815-971817) were synthesized based on 5-(2-hydroxyethoxy) isophthalic acid (H2L) under hydrothermal conditions. The obtained coordination polymers were characterized by IR, elemental analysis, thermal analysis and X-ray diffraction In solid state, these polymers featured 3-D supramolecular structures constructed by 2-D sheets through H-bonds. Investigation of photoluminescence properties of H2L and 1-3 showed all of them exhibited intense fluorescent emissions in the solid state at room temperature.

  8. A rare case of unusual gingival enlargement post radiotherapy

    Directory of Open Access Journals (Sweden)

    Vishal Singh

    2011-01-01

    Full Text Available Oral changes following radiotherapy are not uncommon. Oral mucositis, alteration in salivary gland function, radiation caries, and gingival changes have all been reported following radiotherapy and chemotherapy. The gingival changes seen after radiotherapy may be unusual and often cause diagnostic dilemma. Metastasis to the gingiva has also to be ruled out in these cases. A 30-year-old female patient presented with enlargement of the gingiva of 6 months′ duration and lower lip swelling of 7 months′ duration. She was a known case of carcinoma of nasopharynx and had received radiotherapy and chemotherapy. Based on the history, the clinical appearance of the gingiva, and the other oral changes we considered both post-radiotherapy gingival enlargement and secondary metastasis to gingiva as possibilities. An incisional biopsy was performed (internal bevel gingivectomy. The histopathological report did not reveal any metastatic changes. Thus, we diagnosed post-radiotherapy gingival enlargement. For the multiple carious teeth, extraction and root canal treatment was carried out as necessary. The patient was referred to the department of Oral and Maxillofacial Surgery for management of swelling of the lips, which was diagnosed as lymphedema of the lip. Gingival enlargement is rare post radiotherapy. Such nonplaque-associated gingival enlargement in a patient who has undergone radiotherapy should be subjected to biopsy and histopathological examination to distinguish between secondary metastasis and post-radiation changes.

  9. 40 CFR 190.11 - Variances for unusual operations.

    Science.gov (United States)

    2010-07-01

    ... PROTECTION PROGRAMS ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR NUCLEAR POWER OPERATIONS Environmental Standards for the Uranium Fuel Cycle § 190.11 Variances for unusual operations. The standards specified...

  10. La islamofobia como recurso político: el caso pro-Köln (PRO-NRW

    Directory of Open Access Journals (Sweden)

    Guerrero Enterría, Arturo

    2008-12-01

    Full Text Available This article seeks to analyse, from the case study of the Pro-Köln party, how Islamophobia is used as a resource by some parties on the extreme right in Europe to obtain political returns and electoral support. Using an analysis of the genesis of the party and its electoral program as a starting point, the study dismantles theargument that this party’s main objective is to fight against the Islamisation of Europe, and shows that this is only one means to articulate an ultra-rightist political discourse and that its attempt to stop the construction of the mosque in Köln is only window-dressing to conquer the votes of the citizenry.

  11. Nitrogen segregation and blister formation of 316LN austenitic steel during electron beam welding tests for ITER gravity supports

    Science.gov (United States)

    Lee, P. Y.; Hou, B. L.; Wu, J. H.; Yang, D.; Zhang, G. R.; Zhang, C. P.

    2009-04-01

    316LN has been widely applied in the design of ITER components, such as shield blanket and gravity supports, due to its excellent corrosion resistance and high strength. The behavior of nitrogen in this steel during welding is important for the mechanical properties of the components. In this study, a focused 150 kv high voltage electron beam with 300 mA beam current has been used to weld 316LN steel under vacuum condition. The microstructure and composition of the welding area were observed and analyzed. The influence of welding on the shock resistance and tensile strength at both room temperature and low temperature were examined. It was found that the mechanical properties are strongly related to the defects formed in the welding process.

  12. Synthesis and photoluminescent properties of doped ternary Eu_(1-x)Ln_x(NPPD)_3·DPQ complexes

    Institute of Scientific and Technical Information of China (English)

    李月琴; 李烨; 徐慧华; 陶弦; 张冬梅; 沈应中

    2010-01-01

    Rare earth (RE) ternary complexes of Eu0.5Ln0.5(NPPD)3·(DPQ) (HNPPD=1-(naphthalen-2-yl)-3-phenylpropane-1,3-dione; DPQ= dipyridobenzoquinone) and Eu1-xLax(NPPD)3·(DPQ) (Ln3+=La3+, Gd3+, Sm3+, Pr3+; x=0.0, 0.1, 0.3, 0.5, 0.7, 0.9) were synthesized by the reaction of RECl3·6H2O with HNPPD and DPQ in stoichiometry. The complexes were characterized with IR, elemental analysis, TGA-DSC and wide-angle X-ray diffraction. The UV-Vis absorption spectra and fluorescence properties of the complexes were also investiga...

  13. Synthesis and Characterization of Quaternary Complexes Ln ( CH2 ClCO0 ) 2 ( NO3 ) ( phen)

    Institute of Scientific and Technical Information of China (English)

    咸春颖; 赵曙辉; 朱龙观; 谢学鹏

    2001-01-01

    Many trinary lanthanide complexes have been studied. However, few mixed anion complexes with bidentate heterocyclic amines were synthesized. We synthesized mixed anion complexes Ln ( CHi CICO0 )2 (NO3) (phen) which was determined by elemental analyses. The IR spectra analyses indicate that NO3 ,CH2 C1CO0- and phen are coordinated with Ln. The molar conductances of the complexes at 10-3 mol. L-1 were founded to be between 32.4 and 35.8 S. cma@mol- 1 , suggesting the nonelectrolytes in N Dimethylformamide. And we determined the fluorescent spectra Eu(CH2C1COO)2(NO3) ( phen ) and ESR spectra of Gd( CH2 ClC00 )2 ( NOs ) ( phen ) .

  14. Aqueous Binary Lanthanide(III) Nitrate Ln(NO3)3 Electrolytes Revisited: Extended Pitzer and Bromley Treatments

    Energy Technology Data Exchange (ETDEWEB)

    Chatterjee, Sayandev; Campbell, Emily L.; Neiner, Doinita; Pence, Natasha; Robinson, Troy; Levitskaia, Tatiana G.

    2015-09-11

    To date, only limited thermodynamic models describing activity coefficients of the aqueous solutions of lanthanide ions are available. This work expands the existing experimental osmotic coefficient data obtained by classical isopiestic technique for the aqueous binary trivalent lanthanide nitrate Ln(NO3)3 solutions using a combination of water activity and vapor pressure osmometry measurements. The combined osmotic coefficient database for each aqueous lanthanide nitrate at 25°C, consisting of literature available data as well as data obtained in this work, was used to test the validity of Pitzer and Bromley thermodynamic models for the accurate prediction of mean molal activity coefficients of the Ln(NO3)3 solutions in wide concentration ranges. The new and improved Pitzer and Bromley parameters were calculated. It was established that the Ln(NO3)3 activity coefficients in the solutions with ionic strength up to 12 mol kg-1 can be estimated by both Pitzer and single-parameter Bromley models, even though the latter provides for more accurate prediction, particularly in the lower ionic strength regime (up to 6 mol kg-1). On the other hand for the concentrated solutions, the extended three-parameter Bromley model can be employed to predict the Ln(NO3)3 activity coefficients with remarkable accuracy. The accuracy of the extended Bromley model in predicting the activity coefficients was greater than ~95% and ~90% for all solutions with the ionic strength up to 12 mol kg-1 and and 20 mol kg-1, respectively. This is the first time that the activity coefficients for concentrated lanthanide solutions have been predicted with such a remarkable accuracy.

  15. Design Guidelines for Collaboration and Participation with Examples from the LN4LD (Learning Network for Learning Design)

    OpenAIRE

    2007-01-01

    Burgos, D., Hummel, H. G. K., Tattersall, C., Brouns, F., & Koper, R. (2009). Design Guidelines for Collaboration and Participation with Examples from the LN4LD (Learning Network for Learning Design). In L. Lockyer, S. Bennett, S. Agostinho & B. Harper (Eds.), Handbook of Research on Learning Design and Learning Objects: Issues, Applications and Technologies (Vol. 1, pp 373-389). Hershey, New York: Information Science Reference, IGI Global.

  16. Orthopositronium lifetime at O({alpha}) and O({alpha}{sup 3} ln {alpha}) in closed form

    Energy Technology Data Exchange (ETDEWEB)

    Kniehl, B.A.; Kotikov, A.V.; Veretin, O.L. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2009-09-15

    Recently, the O({alpha}) and O({alpha}{sup 3} ln{alpha}) radiative corrections to the orthopositronium lifetime have been presented in closed analytical form, in terms of basic irrational numbers that can be evaluated numerically to arbitrary precision [Phys. Rev. Lett. 101, 193401 (2008)]. Here, we present the details of this calculation and reveal the nature of these new constants. We also list explicit transformation formulas for generalized polylogarithms of weight four, which may be useful for other applications. (orig.)

  17. Post-Synthetic Shaping of Porosity and Crystal Structure of Ln-Bipy-MOFs by Thermal Treatment

    Directory of Open Access Journals (Sweden)

    Philipp R. Matthes

    2015-07-01

    Full Text Available The reaction of anhydrous lanthanide chlorides together with 4,4′-bipyridine yields the MOFs 2∞[Ln2Cl6(bipy3]·2bipy, with Ln = Pr − Yb, bipy = 4,4′-bipyridine, and 3∞[La2Cl6(bipy5]·4bipy. Post-synthetic thermal treatment in combination with different vacuum conditions was successfully used to shape the porosity of the MOFs. In addition to the MOFs microporosity, a tuneable mesoporosity can be implemented depending on the treatment conditions as a surface morphological modification. Furthermore, thermal treatment without vacuum results in several identifiable crystalline high-temperature phases. Instead of collapse of the frameworks upon heating, further aggregation under release of bipy is observed. 3∞[LaCl3(bipy] and 2∞[Ln3Cl9(bipy3], with Ln = La, Pr, Sm, and 1∞[Ho2Cl6(bipy2] were identified and characterized, which can also exhibit luminescence. Besides being released upon heating, the linker 4,4′-bipyridine can undergo activation of C-C bonding in ortho-position leading to the in-situ formation of 4,4′:2′,2′′:4′′,4′′′-quaterpyridine (qtpy. qtpy can thereby function as linker itself, as shown for the formation of the network 2∞[Gd2Cl6(qtpy2(bipy2]·bipy. Altogether, the manuscript elaborates the influence of thermal treatment beyond the usual activation procedures reported for MOFs.

  18. 2-D and 3-D phosphotungstate-based TM-Ln heterometallic derivatives constructed from dimeric [Ln({alpha}-PW{sub 11}O{sub 39}){sub 2}]{sup 11-} fragments and copper-organic complex linkers

    Energy Technology Data Exchange (ETDEWEB)

    Shang, Sensen [Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004 (China); Zhao, Junwei, E-mail: zhaojunwei@henu.edu.cn [Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004 (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Chen, Lijuan [Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004 (China); Basic Experiment Teaching Center, Henan University, Kaifeng, Henan 475004 (China); Li, Yuye; Zhang, Jingli; Li, Yanzhou [Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004 (China); Niu, Jingyang, E-mail: jyniu@henu.edu.cn [Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004 (China)

    2012-12-15

    Three organic-inorganic hybrid TM-Ln heterometallic phosphotungstates [Cu(dap){sub 2}(H{sub 2}O)][Cu(dap){sub 2}]{sub 3.5}[La({alpha}-HPW{sub 11}O{sub 39}){sub 2}]{center_dot}6H{sub 2}O (1) [Cu(dap){sub 2}(H{sub 2}O)]{sub 0.5}[Cu(dap){sub 2}]{sub 4}[Nd({alpha}-HPW{sub 11}O{sub 39}){sub 2}]{center_dot}4H{sub 2}O (2) and [Cu(dap){sub 2}(H{sub 2}O)]{sub 2}[Cu(dap){sub 2}]{sub 3.5}[Eu({alpha}-PW{sub 11}O{sub 39}){sub 2}]{center_dot}6H{sub 2}O (3) (dap=1,2-diaminopropane) have been hydrothermally synthesized and structurally characterized by elemental analyses, IR spectra, optical diffuse reflectance spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analyses and single-crystal X-ray diffraction. Their common features are that 1-3 all consist of asymmetric sandwich-type subunits [Ln({alpha}-PW{sub 11}O{sub 39}){sub 2}]{sup 11-} and [Cu(dap){sub 2}]{sup 2+} bridges. Both 1 and 2 display the 2-D (4,4)-topological sheets whereas 3 exhibits the 3-D 5-connected (4{sup 6}{center_dot}6{sup 4}) topological framework. The magnetic properties of 2 and 3 and the luminescence performance of 3 have been measured. - Graphical Abstract: Three TM-Ln heterometallic phosphotungstates 1-3 have been synthesized and characterized by elemental analyses, IR spectra, optical diffuse reflectance spectra, X-ray diffraction, thermogravimetric analyses magnetic susceptibility and luminescent properties. Highlights: Black-Right-Pointing-Pointer Cu{sup II}-Ln{sup III} heterometallic polyoxometalates. Black-Right-Pointing-Pointer 2-D and 3-D organic-inorganic hybrid phosphotungstates. Black-Right-Pointing-Pointer 2-D and 3-D structures consisting of Cu{sup II}-Ln{sup III} heterometals.

  19. Fundamentální analýza numerických dat pro automatický trading

    OpenAIRE

    Huf, Petr

    2016-01-01

    Tato práce se zabývá využitím fundamentální analýzy v automatickém obchodování. Technická analýza využívá k predikci ceny hlavně její historické hodnoty a indikátory z této ceny odvozené. Fundamentální analýza naopak využívá informace z různých zdrojů k predikci cenového signálu, přičemž v této práci byly zkoumány pouze kvantitativní zdroje dat. Konkrétně se jedná o počasí, Forex, Google Trends, WikiTrends, historické ceny různých futures a souhrnná fundamentální data (porodnost, migrace, \\do...

  20. Zpracování digitálních signálů z interferometru

    OpenAIRE

    2011-01-01

    Bakalářská práce se zabývá zpracováním digitálního signálu formátu S/PDIF z interferometru Polytec OFV-5000, pomocí měřicí aplikace vytvořené ve vývojovém prostředí LabVIEW. V této práci je popsána teorie laserového měření vibrací a kódování digitálního signálu S/PDIF. Dále je představen systém pro měření vibrací Polytec a systém pro sběr dat National Instruments. Následuje popis vytvořené měřicí aplikace, rozdělen na tři části: dekódování signálu S/PDIF, sběr a zobrazení digitálních dat a sb...

  1. Photoluminescence properties of lanthanide-organic frameworks (LnOFs) with thiophene-2,5-dicarboxylate and acetate

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jing; Wei, Qing; Xie, Gang; Chen, Sanping [Key Lab. of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest Univ., Xi' an, Shaanxi (China); Zhang, Sheng [Key Lab. of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest Univ., Xi' an, Shaanxi (China); College of Chemistry and Chemical Engineering, Baoji Univ. of Arts and Science, Baoji, Shaanxi (China)

    2017-07-17

    S-heterocyclic dicarboxylic acid, thiophene-2,5-dicarboxylic acid (H{sub 2}TDC), was employed to construct a series of lanthanide-organic frameworks (LnOFs) with coligand acetate, formulated as [Ln(TDC)(OAc)(H{sub 2}O)]{sub n} [Ln = Eu (1), Tb (2), Gd (3), Dy (4), Sm (5)] under hydrothermal conditions. Structure analysis reveals that 1-5 have dinuclear 3D metal organic frameworks (MOFs), in which TDC{sup 2-} and OAc{sup -} display (κ{sup 1}-κ{sup 1})-(κ{sup 1}-κ{sup 1})-μ{sub 4} and (κ{sup 2}-κ{sup 1})-μ{sub 2} coordination fashions, respectively. The dehydrated products of all compounds show high thermal stability above 410 C. As for 1, 2, 4, and 5, the photoluminescence analyses exhibit characteristic luminescence emission bands of the corresponding lanthanide ions in the visible region. In particular, compound 2 displays bright green luminescence in the solid state with {sup 5}D{sub 4} lifetime of 0.510 ms and relative high overall quantum yield of 16 %, based on an ideal energy gap between the lowest triplet state energy level of H{sub 2}TDC ligand and the {sup 5}D{sub 4} state energy level of Tb{sup 3+}. The energy transfer mechanisms in compounds 1 and 2 were also discussed. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. A Conceptual Framework for the Electronic Performance Support Systems within IBM Lotus Notes 6 (LN6 Example

    Directory of Open Access Journals (Sweden)

    Servet BAYRAM

    2005-10-01

    Full Text Available A Conceptual Framework for the Electronic PerformanceSupport Systems within IBM Lotus Notes 6 (LN6 Example Assoc. Prof. Dr. Servet BAYRAM Computer Education & Instructional Technologies Marmara University, TURKEYsbayram@marmara.edu.tr ABSTRACT The concept of Electronic Performance Support Systems (EPSS is containing multimedia or computer based instruction components that improves human performance by providing process simplification, performance information and decision support system. EPSS has become a hot topic for organizational development, human resources, performance technology, training, and educational development professionals. A conceptual framework of EPSS is constructed under five interrelated and interdependent domains for educational implications. The domains of the framework are online collaboration, cost-effectiveness, motivation, service management, and performance empowering. IBM Lotus Notes 6 (LN6 is used as an example application tool to illustrate the power of this framework. The framework describes a set of relevant events based upon deductive analyses for improving our understanding of the EPSS and its implications on education and training. The article is also pointed out that there are some similarities between the EPSS’ and the LN6’s specific features within this conceptual framework. It can provide some guidelines and benefits to researchers, educators, and designers as well.

  3. Synthesis and crystal and molecular structure of three heterometallic polymeric compounds (Ln{sub 2}[LnGe{sub 6}(μ-Oedph){sub 6}(μ-O){sub 3}(μ-OH){sub 3}(H{sub 2}O){sub 4}] · xH{sub 2}O){sub n} [Ln = Nd, x ∼ 26 (I); Er, x ∼ 24 (II); Tm, x ∼ 20 (III); H{sub 4}Oedph = 1-hydroxyethylidenediphosphonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Sergienko, V. S., E-mail: sergienko@igic.ras.ru [Russian Academy of Sciences, Kurnakov Institute of General and Inorganic Chemistry (Russian Federation); Martsinko, E. E. [Mechnikov Odessa National University (Ukraine); Ilyukhin, A. B. [Russian Academy of Sciences, Kurnakov Institute of General and Inorganic Chemistry (Russian Federation); Seifullina, I. I. [Mechnikov Odessa National University (Ukraine)

    2015-03-15

    The synthesis and X-ray diffraction study of three heterometallic compounds of general formula (Ln{sub 2}[LnGe{sub 6}(μ-Oedph){sub 6}(μ-O){sub 3}(μ-OH){sub 3}(H{sub 2}O){sub 4}] · xH{sub 2}O){sub n} [Ln = Nd, x ∼ 26 (I); Er, x ∼ 24 (II); Tm, x ∼20 (III); H{sub 4}Oedph = 1-hydroxyethylidenediphosphonic acid] are performed. The basis element of structures I–III is a hexanuclear complex anion [Ge(μ-Oedph)(μ-O){sub 0.5}(μ-OH){sub 0.5}]{sub 6}{sup 9−}, in which bridging hydroxo and oxo ligands are statistically disordered with equally probability. Hexameric units are connected by Ln1(H{sub 2}O){sub 4} fragments into a framework whose channels are completely populated by disordered lanthanide atoms and water molecules.

  4. An unusual case of clear cell meningioma

    Directory of Open Access Journals (Sweden)

    Deb Prabal

    2009-01-01

    Full Text Available Clear-cell meningioma (CCM is an uncommon, aggressive variant of meningioma, usually affecting younger females and having predilection for infratentorial locations. We present a rare case of recurrent supratentorial CCM in a 58-year-old male. Ten years back, he had an intra-axial tumor in the left occipital lobe, which was managed by surgical excision and radiotherapy. Currently, the patient presented with sudden severe headache along with speech and vision disturbances. Neuroimaging revealed an extra-axial parietooccipital tumor, with intratumoural bleed. Histopathology of both tumors showed features of CCM, immunopositive for epithelial membrane antigen (EMA and vimentin. This case illustrates multiple unusual features of a rare variant of meningioma in the form of affection of an adult age group, supratentorial location, recurrence, and intratumoral bleed. It also highlights the importance of incorporating immunohistochemistry in the diagnostic workup, to exclude CCM mimics, each having distinctive biological behavior, and prognostic outcome, and warranting different therapeutic protocols.

  5. Unusually Stable Helical Coil Allotrope of Phosphorus.

    Science.gov (United States)

    Liu, Dan; Guan, Jie; Jiang, Jingwei; Tománek, David

    2016-12-14

    We have identified an unusually stable helical coil allotrope of phosphorus. Our ab initio density functional theory calculations indicate that the uncoiled, isolated straight one-dimensional chain is equally stable as a monolayer of black phosphorus dubbed phosphorene. The coiling tendency and the attraction between adjacent coil segments add an extra stabilization energy of ∼12 meV/atom to the coil allotrope, similar in value to the ∼16 meV/atom interlayer attraction in bulk black phosphorus. Thus, the helical coil structure is essentially as stable as black phosphorus, the most stable phosphorus allotrope known to date. With an optimum radius of 2.4 nm, the helical coil of phosphorus may fit well and even form inside wide carbon nanotubes.

  6. Unusual Cases of Epidermoid cyst: Case Series

    Directory of Open Access Journals (Sweden)

    Lalita Yadav

    2013-09-01

    Full Text Available In the oro-facial region cystic lesions of different etiologies are encountered owing to the presence of the teeth in the jaw bones. A bewildering variety of developmental, odontogenic and non-odontogenic cysts are seen. Epidermoid cyst is a rare developmental cyst of the oro-facial region which results from entrapped epidermal elements without adnexal appendages. Dermoid and epidermoid cysts occur in oro-facial region with an incidence of 6.9-7% and represents less than 0.01% of all oral cavity cysts. Here we report two cases of epidermoid cysts occurring at unusual locations involving upper left maxillary region lateral to the nose and pinna of the ear.

  7. An unusual case of total ophthalmoplegia

    Directory of Open Access Journals (Sweden)

    Chowdhury Ravindra

    2009-01-01

    Full Text Available An eight-year-old male child presented with drooping of the left eyelid with a history of penetrating injury of hard palate by an iron spoon seven days ago, which had already been removed by the neurosurgeon as the computed tomography scan revealed a spoon in the left posterior ethmoid and sphenoid bone penetrating into the middle cranial fossa. On examination, visual acuity was 20/20 in each eye and left eye showed total ophthalmoplegia. Oral cavity revealed a hole in the left lateral part of the hard palate. We managed the case with tapering dose of systemic prednisolone. The total ophthalmoplegia was markedly improved in one month. Cases of foreign bodies in the orbit with intracranial extension are not unusual, but the path this foreign body traveled through the hard palate without affecting the optic nerve, internal carotid artery or cavernous sinus makes an interesting variation.

  8. Unusual presentation in Axenfeld-Rieger syndrome

    Directory of Open Access Journals (Sweden)

    Rajul S Parikh

    2011-01-01

    Full Text Available We report an unusual presentation of a case of Axenfeld-Rieger (A-R syndrome. A 14-year-old male presented with gradual dimness of vision for 1 year and redness of left eye for 3 days. The patient had megalocornea with Haab′s striae in the right eye and posterior embryotoxon in both the eyes. In the left eye, there was a white cord-like structure traversing the anterior chamber with adhesions to iris tissue along its course. On two antiglaucoma medications, his intraocular pressure (IOP was 22 mm Hg in the right eye and 18 mm Hg in the left eye. Gonioscopy revealed a cord-like structure originating at the level of Schwalbe′s line. He underwent right eye trabeculectomy with mitomycin-C. This case highlights a rare presentation of a strange cord-like structure, a rare presentation of A-R syndrome.

  9. Unusual ganglioglioma with extensive calcification and ossification

    Directory of Open Access Journals (Sweden)

    Vikas Shashikant Kavishwar

    2016-01-01

    Full Text Available Ganglioglioma is a slow-growing relatively low-grade mixed glioneuronal tumor with most cases corresponding to the WHO Grade I category. It frequently presents with seizures. The temporal lobe is the most common location followed by frontal, parietal, and occipital lobes. These generally behave in a benign fashion and have a favorable prognosis. We describe a case of a 24-year-old male presenting with convulsions and a calcified parieto-occipital mass. This mass removed from the parietal lobe showed neoplastic glial and dysplastic neuronal tissue amidst extensive areas of calcification and foci of ossification. On immunohistochemistry, the glial component expressed glial fibrillary acidic protein whereas the dysplastic neuronal component expressed synaptophysin and CD34. Epithelial membrane antigen was negative and Ki-67 showed a low proliferative index. After the surgery, the patient is free of neurological symptoms. Widespread calcification and ossification are very unusual in ganglioglioma, which prompted us to report this case.

  10. An unusual case of palmoplantar keratoderma.

    Science.gov (United States)

    Devos, S A; Delescluse, J

    2003-01-01

    A 55-year-old woman with palmoplantar keratoderma presented an associated hyperhidrosis with distinct odour and maceration. She had had the lesions for about 20 years and this seemed to be an isolated case in her family. This case appeared very unusual because there were no signs of acanthokeratolysis in the biopsies. Two months of treatment with acitretin (Neotigason; 25 mg daily), produced a spectacular result: clearance of all the lesions on both hands and a strong diminution of the lesions on the soles. The Unna-Thost variant of palmoplantar keratoderma usually appears in the first few months of life, and it rarely appears in the third decade. The condition is inherited as an autosomal dominant with high penetrance and expressivity. Our subject appeared to be an exception to these two facts.

  11. Radiography of Unusual foreign body in Ruminants

    Directory of Open Access Journals (Sweden)

    Semieka

    Full Text Available The present study was carried out on 10 animals (6 buffaloes, 3 cattle and one camel.The animals were admitted to the Veterinary Teaching Hospital, Assiut University affected by unusual size, type, and location of foreign bodies. Diagnosis and description of the foreign bodies were depend mainly on radiographic examination. Most of the foreign bodies recorded in this study were of metallic origin (needles and nails.These foreign bodies reached to the animals by several routes (ingestion, during surgery and lodged at various areas of animal tissues (throat, Oesophagus, thoracic cavity, reticulum, udder cistern, stifle region. Surgery was performed in most cases for removal of the foreign bodies. [Veterinary World 2010; 3(10.000: 473-475

  12. An unusual case of bilateral granulomatous mastitis.

    Science.gov (United States)

    Pistolese, C A; Di Trapano, R; Girardi, V; Costanzo, E; Di Poce, I; Simonetti, G

    2013-01-01

    Idiopathic granulomatous mastitis (IGM) is an uncommon benign disorder of the breast. At clinical examination, IGM is characterized by an inflammatory process of the breast, usually unilateral. Possible clinical findings are palpable mass with erythematous skin, pain, sterile abscesses, fistula and nipple retraction. Mammography and ultrasound findings are not specific for IGM. Magnetic resonance imaging (MRI) is a useful tool for the differential diagnosis; it is also necessary to delineate the exact extension of the disease and to plan the correct treatment. Final diagnosis is histological. We described an unusual case of IGM with bilateral involvement in a patient with history of pacemaker implantation and IGM typical clinical symptoms. Mammography, ultrasound, and MRI examinations were performed to identify the inflammatory disorder and to plan the correct therapy. Imaging features were correlated with final histological diagnosis of IGM.

  13. An Unusual Case of Bilateral Granulomatous Mastitis

    Directory of Open Access Journals (Sweden)

    C. A. Pistolese

    2013-01-01

    Full Text Available Idiopathic granulomatous mastitis (IGM is an uncommon benign disorder of the breast. At clinical examination, IGM is characterized by an inflammatory process of the breast, usually unilateral. Possible clinical findings are palpable mass with erythematous skin, pain, sterile abscesses, fistula and nipple retraction. Mammography and ultrasound findings are not specific for IGM. Magnetic resonance imaging (MRI is a useful tool for the differential diagnosis; it is also necessary to delineate the exact extension of the disease and to plan the correct treatment. Final diagnosis is histological. We described an unusual case of IGM with bilateral involvement in a patient with history of pacemaker implantation and IGM typical clinical symptoms. Mammography, ultrasound, and MRI examinations were performed to identify the inflammatory disorder and to plan the correct therapy. Imaging features were correlated with final histological diagnosis of IGM.

  14. An unusual case of pancreatic fistula.

    Science.gov (United States)

    Johnston, M J; Prew, C L; Fraser, I

    2013-03-21

    We report an unusual case of a pancreatic fistula communicating with an appendicectomy wound. This occurred following an episode of acute haemorrhagic pancreatitis. The patient was initially admitted with signs and symptoms indicating appendicitis and went to theatre for an open appendicectomy. However, this did not resolve his symptoms and a laparotomy was performed the next day revealing haemorrhagic pancreatitis. He endured a stormy post-operative course, the cause of which was found to be an external pancreatic fistula with discharge of amylase-rich fluid from the Lanz incision. A trial of conservative management failed despite multiple percutaneous drainage procedures and treatment with broad-spectrum antibiotics. After a second opinion was sought, it was decided to fit a roux loop anastomosis between the head of the pancreas and the duodenum to divert the fistulous fluid. This procedure was a success and the patient remains well 2 years later.

  15. Osteomyelitis with proliferative periostitis: an unusual case.

    Science.gov (United States)

    Tong, Antonio C K; Ng, Irene O L; Yeung, K M Au

    2006-11-01

    Chronic osteomyelitis with subperiosteal new bone formation results from periosteal reaction to chronic inflammatory/infectious stimulation. In the maxillofacial region, it has traditionally been termed Garrè's osteomyelitis with proliferative periostitis and more recently periostitis ossificans. The term Garrè's osteomyelitis has been regarded as a misnomer by many authors in the recent literature. The term chronic osteomyelitis with proliferative periostitis, although cumbersome, is considered to be the most accurate description of the pathology. It usually affects the mandible of young patients secondary to dental infection. Management involves removal of the source of infection and antibiotic treatment. We present an unusual case of chronic osteomyelitis with proliferative periostitis affecting the mandible of a 12-year-old patient. The source of infection was related to the developing lower left third molar, which had apparently no communication with the oral cavity.

  16. Unusual Presentation of Cutaneous Leishmaniasis: Ocular Leishmaniasis

    Directory of Open Access Journals (Sweden)

    Masoud Doroodgar

    2017-01-01

    Full Text Available The leishmaniases are parasitic diseases that are transmitted to humans by infected female sandflies. Cutaneous leishmaniasis (CL is one of 3 main forms of the disease. CL is the most common form of the disease and is endemic in many urban and rural parts of Iran and usually caused by two species of Leishmania: L. major and L. tropica. We report a case of unusual leishmaniasis with 25 lesions on exposed parts of the body and right eyelid involvement (ocular leishmaniasis. The patient was a 75-year-old male farmer referred to health care center in Aran va Bidgol city. The disease was diagnosed by direct smear, culture, and PCR from the lesions. PCR was positive for Leishmania major.

  17. An unusual clinical presentation of gingival melanoacanthoma

    Directory of Open Access Journals (Sweden)

    S. P. K. Kennedy Babu

    2013-01-01

    Full Text Available Gingival melanoacanthoma is a rare, benign pigmented lesion characterized clinically by sudden onset and rapid growth of a macular brown black lesion and histologically by acanthosis of superficial epithelium and proliferation of dendritic melanocytes. This article reports a previously undescribed case of pigmented unilateral diffuse gingival enlargement, which on histopathological examination proved to be melanoacanthoma. Intraoral examination revealed pigmented unilateral diffuse gingival enlargement in relation to second and third quadrants buccally, palatally/lingually. Based on these clinical findings, gingivectomy was performed and the excised tissue was sent for biopsy. Microscopic examination revealed acanthotic and parakeratotic surface epithelium with dendritic melanocytes distributed in basal and suprabasal layers of the epithelium. 1 year follow-up recall revealed no recurrence of lesion at the surgical sites. Our patient exhibits an unusual clinical presentation of melanoacanthoma of gingiva. Pigmented gingival overgrowth of recent origin and without any etiologic factors warrants histopathologic examination.

  18. Unusual early-onset Huntingtons disease.

    Science.gov (United States)

    Vargas, Antonio P; Carod-Artal, Francisco J; Bomfim, Denise; Vázquez-Cabrera, Carolina; Dantas-Barbosa, Carmela

    2003-06-01

    Huntington's disease is an autosomal dominant progressive neurodegenerative disorder characterized by involuntary movements, cognitive decline, and behavioral disorders leading to functional disability. In contrast to patients with adult onset, in which chorea is the major motor abnormality, children often present with spasticity, rigidity, and significant intellectual decline associated with a more rapidly progressive course. An unusual early-onset Huntington's disease case of an 11-year-old boy with severe hypokinetic/rigid syndrome appearing at the age of 2.5 years is presented. Clinical diagnosis was confirmed by polymerase chain reaction study of the expanded IT-15 allele with a compatible size of 102 cytosine-adenosine-guanosine repeats L-Dopa mildly ameliorated rigidity, bradykinesia, and dystonia. We conclude that Huntington's disease should be included in the differential diagnoses of regressive syndromes of early childhood.

  19. An Unusual Presentation of Biliary Ascariasis

    Directory of Open Access Journals (Sweden)

    Arsad Bashir Khan, Sanjay Kumar Bhasin, Rajesh Kumar Bhagat, R. K. Chrungoo

    2007-01-01

    Full Text Available Ascariasis is one of the most common disease in human being worldwide. Ascariasis is 2nd to gall stone asa cause of biliary symptoms. The invasion of biliary tract by round worms during early post operativeperiod is an infrequent but serious complication. We present 42 years old man operated for cholelithiasiswith Choledocholthiasis on whom choledochotomy and T -Tube insertion was done. On 5th postoperativeday Ascaris extruded peri-T-Tube and immediate T - Tube cholangiogram done that showed multiplefilling defects in Common Bile Duct (CBD. Patient was managed with saline irrigation of CBD viaT-Tube and anti-heliminthic was given. In view of its rarity and unusual presentation the case is beingreported.

  20. Peritoneal amyloidosis: unusual localization of gastrointestinal amyloidosis.

    Science.gov (United States)

    Karoui, Sami; Haddad, Wafa; Serghini, Meriem; Ghorbel, Imed Ben; Chebbi, Faouzi; Azzouz, Heifa; Haouet, Slim; Houmen, Habib; Safta, Zoubeir Ben; Boubaker, Jalel; Filali, Azza

    2011-08-01

    Amyloidosis is a rare disease that results from the extracellular deposition of amorphous fibrillar protein. It is usually observed in a systemic form. Gastrointestinal involvement is frequent but peritoneal localization is unusual. A 43-year-old male was investigated for nephritic colic. Morphologic explorations revealed small intestine agglomerans in the periumbilical region, infiltration of peritoneal fat and multiple coelio-mesenteric lymph nodes. There were no clinical or biological abnormalities and endoscopic examinations were normal. The patient then underwent an exploratory laparoscopy. Macroscopically false membranes were seen throughout the peritoneum and small bowel without ascites. Anatomopathologic examination diagnosed peritoneal amyloidosis. After several investigations a diagnosis of a primary peritoneal amyloidosis was confirmed. The patient was treated with melphalan and prednisone with a favorable outcome. Our case illustrates a particular presentation of peritoneal amyloidosis. Despite improved imaging methods, peritoneal biopsy remains essential for diagnosis.

  1. Supernumerary teeth: Report of four unusual cases

    Directory of Open Access Journals (Sweden)

    Arun Kumar

    2012-01-01

    Full Text Available Supernumerary tooth denotes duplication of tooth in the normal series. It is a developmental anomaly and has been argued to arise from multiple etiologies. These teeth may remain embedded in the alveolar bone or can erupt into the oral cavity. The supernumerary tooth might cause esthetic and/or functional problems, especially if it is situated in the maxillary anterior region. Complications reported were delayed or prevented eruption of succedaneous teeth, displacement or rotation, crowding of the affected region, abnormal diastema, dilacerations, cystic formation, and sometime eruption into the nasal cavity. In this case report, four unusual cases of supernumerary teeth that resulted in varying degrees of disturbances in permanent dentition are presented. Conservative surgical intervention and light orthodontic forces were used to bring the teeth into normal position with minimal disturbance to the surrounding oral structures.

  2. An unusual complication of unsafe abortion

    Directory of Open Access Journals (Sweden)

    Sunita Gupta

    2011-01-01

    Full Text Available Unsafe abortion is a significant medical and social problem worldwide. In developing countries, most of the unsafe abortions are performed by untrained personnel leading to high mortality and morbidity. Case Report: A 30 year-old female, gravida 7, para 6 underwent uterine evacuation for heavy bleeding per vaginum following intake of abortifacient to abort a 14 weeks gestation. The procedure was performed at a rural setup and her bowel was pulled out of the introitus through the perforated wound, an unusual complication of unsafe abortion. Illiteracy, unawareness about health services, and easy accessibility to untrained abortion providers lead to very high mortality and morbidity in India. There is unmet need to bring awareness among the people about the safe and effective methods of contraception and abortion services to avoid such complications.

  3. Unusual intraosseous transmigration of impacted tooth

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Santosh; Urala, Arun Srinivas; Kamath, Abhay Taranath; Jayaswal, Priyanka; Valiathan, Ashima [Manipal College of Dental Sciences, Manipal (India)

    2012-03-15

    Transmigration of an impacted tooth through the symphyseal suture is a rare and special developmental anomaly of unknown etiology that is unique to the mandibular canine. Maxillary canine transmigration is even rarer. Transmigrated canines are particularly significant due to the aesthetic and functional importance. A maxillary lateral incisor crossing the mid-palatal suture has never been reported in the literature. The aim of this report is to present the first case of simultaneous transmigration of a lateral incisor and canine in the maxilla. The paper also reports four unusual cases of unilateral canine transmigration in the maxilla and mandible and successful eruption of one of the transmigrated mandibular canines following orthodontic traction. Etiology of transmigration and its clinical considerations are also discussed.

  4. Unusual Presentation of Cutaneous Leishmaniasis: Ocular Leishmaniasis

    Science.gov (United States)

    Doroodgar, Masoud; Doroodgar, Moein

    2017-01-01

    The leishmaniases are parasitic diseases that are transmitted to humans by infected female sandflies. Cutaneous leishmaniasis (CL) is one of 3 main forms of the disease. CL is the most common form of the disease and is endemic in many urban and rural parts of Iran and usually caused by two species of Leishmania: L. major and L. tropica. We report a case of unusual leishmaniasis with 25 lesions on exposed parts of the body and right eyelid involvement (ocular leishmaniasis). The patient was a 75-year-old male farmer referred to health care center in Aran va Bidgol city. The disease was diagnosed by direct smear, culture, and PCR from the lesions. PCR was positive for Leishmania major. PMID:28210511

  5. New and unusual scaffolds in medicinal chemistry.

    Science.gov (United States)

    Marson, Charles M

    2011-11-01

    Contemporary medicinal chemistry faces diverse challenges from several directions, including the need for both potency and specificity of any therapeutic agent; the increasingly demanding requirements of low toxicity shown across all patients treated; and the need for novelty in intellectual property, given the extensive use of benzenoid and heteroaromatic ring systems in numerous patents. Increasingly, such challenges are being met by a shift to new and/or unusual ring systems (scaffolds) that lie outside the field of (hetero)aromatic systems. This critical review surveys a necessarily limited selection of currently atypical scaffolds, chiefly drawn from the literature of the last three years, that have found application in medicinal chemistry, some being present in agents with therapeutic potential while others are found in agents already in clinical use (163 references).

  6. Supernumerary teeth: Report of four unusual cases.

    Science.gov (United States)

    Kumar, Arun; Namdev, Ritu; Bakshi, Lokesh; Dutta, Samir

    2012-04-01

    Supernumerary tooth denotes duplication of tooth in the normal series. It is a developmental anomaly and has been argued to arise from multiple etiologies. These teeth may remain embedded in the alveolar bone or can erupt into the oral cavity. The supernumerary tooth might cause esthetic and/or functional problems, especially if it is situated in the maxillary anterior region. Complications reported were delayed or prevented eruption of succedaneous teeth, displacement or rotation, crowding of the affected region, abnormal diastema, dilacerations, cystic formation, and sometime eruption into the nasal cavity. In this case report, four unusual cases of supernumerary teeth that resulted in varying degrees of disturbances in permanent dentition are presented. Conservative surgical intervention and light orthodontic forces were used to bring the teeth into normal position with minimal disturbance to the surrounding oral structures.

  7. Unusual presentation of twisted ovarian cyst

    Directory of Open Access Journals (Sweden)

    Vineet V Mishra

    2016-01-01

    Full Text Available Ovarian torsion (also termed as adnexal torsion refers to partial or complete rotation of the ovary and a portion of fallopian tube along its supplying vascular pedicle. It occurs commonly in reproductive age group; more on the right side (60% and often presents with acute lower abdominal pain lasting for few hours and up to 24 h, accounting for 2.7% of acute gynecological conditions. It is one of the devastating conditions, hampering blood supply of ovary which may lead to total necrosis of ovarian tissue and complications, if not diagnosed and managed in time. Hence, we present a case on a twisted ovarian cyst in postmenopausal woman with unusual symptomatology leading to delayed diagnosis and loss of an ovary.

  8. Unusual signs in quantum field theory

    Science.gov (United States)

    O'Connell, Donal

    Quantum field theory is by now a mature field. Nevertheless, certain physical phenomena remain difficult to understand. This occurs in some cases because well-established quantum field theories are strongly coupled and therefore difficult to solve; in other cases, our current understanding of quantum field theory seems to be inadequate. In this thesis, we will discuss various modifications of quantum field theory which can help to alleviate certain of these problems, either in their own right or as a component of a greater computational scheme. The modified theories we will consider all include unusual signs in some aspect of the theory. We will also discuss limitations on what we might expect to see in experiments, imposed by sign constraints in the customary formulation of quantum field theory.

  9. Anubhoothi: a psychopathology of unusual sexual experience

    Directory of Open Access Journals (Sweden)

    G Ragesh

    2016-07-01

    Full Text Available The case history and management of a 26 years old adult is reported who presented with an unusual symptom of sexual experience, in the background of symptoms of depression and anxiety; had been given multiple diagnoses at multiple points of time and treated with multiple medications. On establishment of rapport, he revealed details of his unusual experiences, which had been unexplored. When he was about 11 years and ten months, he sat next to a lady; he could perceive a particular experience for the first time in his life. And next time with another lady too he perceived a particular type of smell (“madaka gandha” meaning an intoxicating smell along with the other feelings. He began to have these feelings whenever he was in the vicinity of a female except his mother and sister. The smell reminded him of roses vaguely and was at least ten to 20 times more pleasurable than an orgasm that he got with masturbation. These feelings were more pleasurable than he could ever imagine and happened always with the presence of a female in the vicinity. This was never associated with periods of unresponsiveness or any other history suggestive of seizures. He titled the experience as “anubhoothi”. These experiences occurred on a regular basis for a period of ten months following which there was abrupt cessation of the same, without any intervention. Later he developed all symptoms. A coordinated management plan spearheaded by the multi-disciplinary treatment team could bring down his symptoms as well as make him functional. This case indicates that it is essential to explore abnormalities of experiences to understand the psychopathology and plan management.

  10. Cognitive bias and unusual experiences in childhood.

    Science.gov (United States)

    Hassanali, Nedah; Ruffell, Tamatha; Browning, Sophie; Bracegirdle, Karen; Ames, Catherine; Corrigall, Richard; Laurens, Kristin R; Hirsch, Colette; Kuipers, Elizabeth; Maddox, Lucy; Jolley, Suzanne

    2015-08-01

    Cognitive therapy is recommended for children with psychotic-like, or unusual, experiences associated with distress or impairment (UEDs; UK National Institute for Health and Care Excellence, 2013 [1]). Accurate models of the psychological underpinnings of childhood UEDs are required to effectively target therapies. Cognitive biases, such as the jumping to conclusions data-gathering bias (JTC), are implicated in the development and maintenance of psychosis in adults. In this study, we aimed to establish the suitability for children of a task developed to assess JTC in adults. Eighty-six participants (aged 5-14 years) were recruited from Child and Adolescent Mental Health Service (CAMHS) and community (school) settings, and completed the probabilistic reasoning ('Beads') task, alongside measures of intellectual functioning, general psychopathology, and UEDs. Self-reported reasoning strategy was coded as 'probabilistic' or 'other'. Younger children (5-10 years) were more likely than older children (11-14 years) to JTC (OR = 2.7, 95 % CI = 1.1-6.5, p = 0.03); and to use non-probabilistic reasoning strategies (OR = 9.4, 95 % CI = 1.7-48.8, p = 0.008). Both UED presence (OR = 5.1, 95 % CI = 1.2-21.9, p = 0.03) and lower IQ (OR = 0.9, 95 % CI = 0.9-1.0, p = 0.02) were significantly and independently associated with JTC, irrespective of age and task comprehension. Findings replicate research in adults, indicating that the 'Beads' task can be reliably employed in children to assess cognitive biases. Psychological treatments for children with distressing unusual experiences might usefully incorporate reasoning interventions.

  11. Separation of Lanthanoids by SiO{sub 2}-P Adsorbent Impregnated with Extractants - 13103

    Energy Technology Data Exchange (ETDEWEB)

    Yamanishi, Kei; Mimura, Hitoshi; Usuda, Shigekazu [Department of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Aramaki-Aza-Aoba 6-6-01-2, Aoba-ku, Sendai-shi, Miyagi-ken, 980-8579 (Japan); Sasaki, Yuji; Morita, Yasuji [Research Group for Aqueous Separation Chemistry, Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki-ken, 319-1195 (Japan)

    2013-07-01

    The adsorption and separation properties of lanthanoids (Ln) were investigated for the mutual separation of trivalent minor actinoids (MA) by using different adsorbents of hydrophobic extractant/SiO{sub 2}-P in solutions of hydrophilic extractant/HNO{sub 3}. The synergistic effect by use of the hydrophobic and hydrophilic extractants was evaluated by batch and column experiments. The results of batch experiments showed the synergistic effect which lowered the K{sub d} values of Ln. In column experiments, effective mutual separation between Nd and Sm was demonstrated. These results suggest that the mutual separation between Am and Cm is possible because the K{sub d} values of Am and Cm are probably similar to those of Nd and Sm. (authors)

  12. Structure of Ln[sub 2](PO[sub 3]H)[sub 3]. H[sub 2]O (Ln=Pr, Nd). Structure de Ln[sub 2](PO[sub 3]H)[sub 3]. H[sub 2]O (Ln=Pr, Nd)

    Energy Technology Data Exchange (ETDEWEB)

    Foulon, J.D.; Durand, J.; Cot, L. (Lab. de Physicochimie des Materiaux, Ecole Nationale Superieure de Chimie, 34 - Montpellier (France)); Tijani, N.; Rafiq, M. (Lab. de Chimie Minerale Appliquee, Faculte des Sciences, Fes (Morocco))

    1993-01-15

    Dipraseodymium triphosphite monohydrate, Pr[sub 2](PO[sub 3]H)[sub 3].H[sub 2]O, M[sub r]=539.8, monoclinic, P2[sub 1]/n, a=9.620(2), b=8.005(1), c=13.119(2) A, [beta]=108.98(1)deg, V=955.4(3) A[sup 3], Z=4, D[sub m]=3.72(1), D[sub x]=3.754 Mg m[sup -3], [lambda](Mo K[alpha])=0.71073 A, [mu]=10.68 mm[sup -1], F(000)=992, T=293 K, R=0.025 for 1947 independent reflections. Dineodymium triphosphite monohydrate, Nd[sub 2](PO[sub 3]H)[sub 3].H[sub 2]O, M[sub r]=546.4, monoclinic, P2[sub 1]/n, a=9.581(2), b=7.980(2), c=13.056(3) A, [beta]=108.95(1)deg, V=944.2(4) A[sup 3], Z=4, D[sub m]=3.81(1), D[sub x]=3.845 Mg m[sup -3], [lambda](Mo K[alpha])=0.71073 A, [mu]=11.51 mm[sup -1], F(000)=1000, T=293 K, R=0.0305 for 1992 independent reflections. The structure contains three independent phosphite anions. Both Ln[sup 3+] are eight-coordinated: One by eight O atoms of six different phosphite anions, but the other by only seven O atoms of six different phosphite anions and one water O atom. (orig.).

  13. Metabolic fate of L-(N-13) glutamate in normal isolated myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Keen, R.E.; Krivokapich, J.; Barrio, J.R.; Douglas, A.; Wittmer, S.; Shine, K.; Phelps, M.E.

    1984-01-01

    In the present work nitrogen flux of an amino acid in myocardium is followed via arterial bolus injection of non-carrier added L-(N-13)glutamate (N-13 GLU) into the isolated rabbit septa. Incorporation of nitrogen-13 into (N-13)aspartate (N-13 ASP)(16%) and (N-13)alanine (N-13 ALA)(14%) predominates over (N-13)glutamine (N-13 GLN) (3.2%) as determined by reversed phase HPLC in normal septa 6 min after bolus injection. No N-13 ammonia or N-13 urea is detected. Introduction of the transaminase inhibitor aminooxyacetate (AOA, 2 nM) into perfusate completely blocked transaminase reaction and increased N-13 GLN (7.3%) and free N-13 ammonia (4.0%), probably resulting from glutamate dehydrogenase reaction. Inclusion of 2mM pyruvate in the perfusate resulted in 3 fold increase in N-13 ALA (44%), slight increase in N-13 GLN (5.0%) and significant decrease in N-13 ASP. Addition of 2mM AOA in the presence of pyruvate blocked production of N-13 ASP and N-13 ALA, and increased N-13 GLN slightly (6.0%). All studies had similar residual fractions (50%) except AOA treated septa (23%) indicating decreased metabolic trapping of the N-13 label. In conclusion, nitrogen-13 distribution in tissue is primarily governed by glutamate interaction with transaminases. Although the Michaelis constants of glutamate for GOT (Km = 4 nM, pig heart), GPT (Km = 8.1 mM, beef heart) and glutamine synthetase (Km = 2.5 mM, ovine brain) are similar, the transaminases play a predominant role because of their great abundance in myocardial tissue.

  14. Correlation between aggregation and extracting properties in solvent extraction systems: extraction of actinides (III) and lanthanides (III) by a malonamide in non acidic media

    Energy Technology Data Exchange (ETDEWEB)

    Meridiano, Y.; Berthon, L.; Lagrave, S.; Crozes, X.; Sorel, C.; Testard, F.; Zemb, T. [CEA Marcoule, DEN/DRCP/SCPS/LCSE, 30207Bagnols sur Ceze (France)

    2008-07-01

    The organic phases of the DIAMEX (Diamide Extraction) process, allowing the co-extraction of actinides(III) and lanthanides(III) from high level radioactive wastes using a malonamide extractant molecule (DMDOHEMA) diluted in alkanes, are investigated. The aim of this study is to establish a link between different structures/organizations of diamide extractants and their extracting properties towards An(III) and Ln(III) cations. It is demonstrated that diamide, which are amphiphilic molecules, are organized in different structures (monomers, reverse micelles, lamellar phases..). This study deals with the effect of the composition of the extracting system on the extracting and aggregation properties of the DMDOHEMA solutions. The effects of the extractant (DMDOHEMA diluted in n-heptane) and metal concentrations (for a given extractant concentration) from a LiNO{sub 3} aqueous phase are investigated at two scales: at the supra-molecular scale by characterizing the aggregation by vapor-pressure osmometry (VPO) and small angle neutron and X-ray scattering (SANS and SAXS) experiments, and at the molecular scale by quantifying the extracted solutes (metal nitrate and water) and by determining the stoichiometries of the extracted complexes by electro-spray mass spectrometry (ESI-MS). The extraction equilibria can then be modeled by two approaches: a classical approach in solvent extraction based on mass action laws to determine extraction equilibria and their associated thermodynamic constants, and a physical chemical approach which consists in considering the extracted ions as adsorbed on a specific available surface of the extractant molecule. Thus, the extraction equilibrium can be considered as a sum of Langmuir isotherms corresponding to the different states of aggregation. The resulting constants are representative of both extraction efficiency and organic phase structure. (authors)

  15. Crystal structure and dielectric properties of Ca(0.85)Nd(0.1)TiO(3) - LnAlO(3) ceramics.

    Science.gov (United States)

    Eung, S; Dong, H; Yang, Jun-Mo; Hyung, S; Nur, I; Ohsato, Hitoshi

    2008-05-01

    The microwave dielectric properties of Ca(0.85)Nd(0.1)TiO(3) - LnAlO(3) (Ln = Sm, Gd, Dy, Er) ceramics are investigated in this paper. The structural characteristics of the specimens were evaluated by Rietveld refinement of Xray diffraction (XRD) patterns and high-resolution transmission electron microscopy (HRTEM). Solid solution limits were dependent on the ionic radius of Ln(3+) ions. With the decrease of the ionic radius of the Ln(3+) ions, the thermal stability of the resonant frequency decreases. This can be attributed to the increased level of oxygen octahedral distortion caused by the increase in the B-site bond valence in the ABO(3) perovskite structure. The dielectric constant (K) and the quality factor (Qf) of the specimens were dependent on the polarizability and grain size, respectively.

  16. The effect of lanthanides on color properties of the (Bi2O30.7(Ln2O30.3 compounds

    Directory of Open Access Journals (Sweden)

    Šulcová P.

    2008-01-01

    Full Text Available (Bi2O30.7(Ln2O30,3 solid solutions were synthesized as new inorganic yellow and orange pigments and their color properties have been investigated as possible ecological materials. The pigments were prepared by the solid state reaction of mixed oxides (Bi2O30.7(Ln2O30.3 of various rare earth cations (Ln = Eu, Gd, Tm, Yb and Lu. All the synthesized pigment samples were found to have color coordinates, low a* and high b* and exhibit the color from pale light yellow to orange. Reflectance spectra of the samples show high reflectance percentage in the 600 - 700 nm range. Characterization of the (Bi2O30.7(Ln2O30,3 solid solutions suggests that they have a potential to be alternative yellow colorants for paints, inks, plastics, and ceramics.

  17. Genetic and proteomic characterization of rpoB mutations and their effect on nematicidal activity in Photorhabdus luminescens LN2.

    Directory of Open Access Journals (Sweden)

    Xuehong Qiu

    Full Text Available Rifampin resistant (Rif(R mutants of the insect pathogenic bacterium Photorhabdus luminescens LN2 from entomopathogenic nematode Heterorhabditis indica LN2 were genetically and proteomically characterized. The Rif(R mutants showed typical phase one characters of Photorhabdus bacteria, and insecticidal activity against Galleria mellonella larvae, but surprisingly influenced their nematicidal activity against axenic infective juveniles (IJs of H. bacteriophora H06, an incompatible nematode host. 13 out of 34 Rif(R mutants lost their nematicidal activity against H06 IJs but supported the reproduction of H06 nematodes. 7 nematicidal-producing and 7 non-nematicidal-producing Rif(R mutants were respectively selected for rpoB sequence analysis. rpoB mutations were found in all 14 Rif(R mutants. The rpoB (P564L mutation was found in all 7 mutants which produced nematicidal activity against H06 nematodes, but not in the mutants which supported H06 nematode production. Allelic exchange assays confirmed that the Rif-resistance and the impact on nematicidal activity of LN2 bacteria were conferred by rpoB mutation(s. The non-nematicidal-producing Rif(R mutant was unable to colonize in the intestines of H06 IJs, but able to colonize in the intestines of its indigenous LN2 IJs. Proteomic analysis revealed different protein expression between wild-type strain and Rif(R mutants, or between nematicidal-producing and non nematicidal-producing mutants. At least 7 putative proteins including DsbA, HlpA, RhlE, RplC, NamB (a protein from T3SS, and 2 hypothetical proteins (similar to unknown protein YgdH and YggE of Escherichia coli respectively were probably involved in the nematicidal activity of LN2 bacteria against H06 nematodes. This hypothesis was further confirmed by creating insertion-deletion mutants of three selected corresponding genes (the downregulated rhlE and namB, and upregulated dsbA. These results indicate that the rpoB mutations greatly influence the

  18. A new continuous two-step molecular precursor route to rare-earth oxysulfides Ln{sub 2}O{sub 2}S

    Energy Technology Data Exchange (ETDEWEB)

    De Crom, N. [Institute of Condensed Matter and Nanosciences/MOST, Universite Catholique de Louvain, Place Louis Pasteur, 1, L4.01.03, B-1348 Louvain-la-Neuve (Belgium); Devillers, M., E-mail: michel.devillers@uclouvain.be [Institute of Condensed Matter and Nanosciences/MOST, Universite Catholique de Louvain, Place Louis Pasteur, 1, L4.01.03, B-1348 Louvain-la-Neuve (Belgium)

    2012-07-15

    A continuous two-step molecular precursor pathway is designed for the preparation of rare-earth oxysulfides Ln{sub 2}O{sub 2}S (Ln=Y, La, Pr, Nd, Sm-Lu). This new route involves a first oxidation step leading to the rare-earth oxysulfate Ln{sub 2}O{sub 2}SO{sub 4} which is subsequently reduced to the rare-earth oxysulfide Ln{sub 2}O{sub 2}S by switching to a H{sub 2}-Ar atmosphere. The whole process occurs at a temperature significantly lower than usual solid state synthesis (T{<=}650 Degree-Sign C) and avoids the use of dangerous sulfur-based gases, providing a convenient route to the synthesis of the entire series of Ln{sub 2}O{sub 2}S. The molecular precursors consist in heteroleptic dithiocarbamate complexes [Ln(Et{sub 2}dtc){sub 3}(phen)] and [Ln(Et{sub 2}dtc){sub 3}(bipy)] (Et{sub 2}dtc=N,N-diethyldithiocarbamate; phen=1,10-phenanthroline; bipy=2,2 Prime -bipyridine) and were synthesized by a new high yield and high purity synthesis route. The nature of the molecular precursor determines the minimum synthesis temperature and influences therefore the purity of the final Ln{sub 2}O{sub 2}S crystalline phase. - Graphical abstract: A continuous two-step molecular precursor pathway was designed for the preparation of rare-earth oxysulfides Ln{sub 2}O{sub 2}S (Ln=Y, La, Pr, Nd, Sm-Lu), starting from heteroleptic dithiocarbamate complexes. The influence of the nature of the molecular precursor on the minimum synthesis temperature and on the purity of the final Ln{sub 2}O{sub 2}S crystalline phase is discussed. Highlights: Black-Right-Pointing-Pointer A new high yield and high purity synthesis route of rare earth dithiocarbamates is described. Black-Right-Pointing-Pointer These compounds are used as precursors in a continuous process leading to rare-earth oxysulfides. Black-Right-Pointing-Pointer The oxysulfides are obtained under much more moderate conditions than previously described.

  19. Unusual tumour ablations: report of difficult and interesting cases

    Science.gov (United States)

    Mauri, Giovanni; Nicosia, Luca; Varano, Gianluca Maria; Shyn, Paul; Sartori, Sergio; Tombesi, Paola; Di Vece, Francesca; Orsi, Franco; Solbiati, Luigi

    2017-01-01

    Image-guided ablations are nowadays applied in the treatment of a wide group of diseases and in different organs and regions, and every day interventional radiologists have to face more difficult and unusual cases of tumour ablation. In the present case review, we report four difficult and unusual cases, reporting some tips and tricks for a successful image-guided treatment. PMID:28487751

  20. Oat cell carcinoma of the esophagus: Unusual radiological appearances

    Energy Technology Data Exchange (ETDEWEB)

    Bedi, D.G.; Shaw, M.T.

    1986-08-01

    Primary oat cell carcinoma of the esophagus is a very rare tumour. The radiographic appearance of the three cases described in this paper are unusual because they resemble benign lesions such as leiomyoma, fibrous polyp and candidiasis. It would be interesting to investigate whether such an unusual appearance is common for this neoplasm.

  1. [Castleman's disease with abdominal localization. Report of an unusual case].

    Science.gov (United States)

    Russo, R; Vertemati, G; Carzaniga, P L; Ballerini, A; Rossi, G; Zuccoli, E

    1995-10-01

    Castleman's disease is an unusual condition characterized by uncontrolled growth of lymphoid tissue. The first case was recorded by Castleman in 1956. In this paper a case of the above-mentioned disease is reported with regard to its unusual clinica-histologic aspect (localized form of plasmacellular type) and surgical therapeutic strategies.

  2. Imaging findings of unusual intra- and extrahepatic portosystemic collaterals

    Energy Technology Data Exchange (ETDEWEB)

    Ito, K. [Department of Radiology, Yamaguchi University School of Medicine, Yamaguchi (Japan)], E-mail: itokatsu@med.kawasaki-m.ac.jp; Fujita, T.; Shimizu, A.; Sasaki, K.; Tanabe, M.; Matsunaga, N. [Department of Radiology, Yamaguchi University School of Medicine, Yamaguchi (Japan)

    2009-02-15

    We describe unusual portosystemic shunts demonstrated using computed tomography (CT) and magnetic resonance imaging (MRI), including gallbladder varices, aberrant left gastric vein to left portal vein collaterals, intrahepatic and transhepatic portosystemic venous shunt, and mesenteric varices. Familiarity with the CT and MRI features of unusual portosystemic shunts will help in making the correct diagnosis for affected patients.

  3. Unusual anatomical detection of a third molar in the infratemporal fossa.

    Science.gov (United States)

    Corega, C; Vaida, L; Festila, D; Bertossi, D

    2013-01-01

    Third molar presence in the infratemporal fossa is a rare event and it has been reported previously only two times in the literature, except for the cases which arise from complications occurring during the extraction of the impacted upper third molar. Due to the presence of important vessel bundles and nerves in this area, third molar removal requires a correct surgical management in order to avoid many possible serious side effects. We report an unusual case of upper third molar detected in the infratemporal fossa, which has been thoroughly investigated radiologically and removed through a safe surgical approach.

  4. ln vitro propagation of Hylocereus purpusii Britton & Rose, a mexican species in danger of extinction

    OpenAIRE

    Manuel de Feria; Daniel Rojas; Maité Chávez; Mireya Reyna; Elisa Quiala; Juan Solís; Florentina Zurita

    2012-01-01

    The purpose ofthis workwasto evalúate different conditions and culture parametersforthein vitro establishment and multiplicaron of Hylocereus purpusii. Seeds were used as plant material and a workflowwas developed as an alternative forthe propagation and recovery ofthis species in danger of extinction. ln the establishment phase, the best result was obtained in the treatment with 1% NaOCI for 15 minutes achieving a 90% of germinated seeds and a final 77.7% of in vitro established plants. ln t...

  5. Robust real-time unusual event detection using multiple fixed-location monitors.

    Science.gov (United States)

    Adam, Amit; Rivlin, Ehud; Shimshoni, Ilan; Reinitz, Daviv

    2008-03-01

    We present a novel algorithm for detection of certain types of unusual events. The algorithm is based on multiple local monitors which collect low-level statistics. Each local monitor produces an alert if its current measurement is unusual, and these alerts are integrated to a final decision regarding the existence of an unusual event. Our algorithm satisfies a set of requirements that are critical for successful deployment of any large-scale surveillance system. In particular it requires a minimal setup (taking only a few minutes) and is fully automatic afterwards. Since it is not based on objects' tracks, it is robust and works well in crowded scenes where tracking-based algorithms are likely to fail. The algorithm is effective as soon as sufficient low-level observations representing the routine activity have been collected, which usually happens after a few minutes. Our algorithm runs in realtime. It was tested on a variety of real-life crowded scenes. A ground-truth was extracted for these scenes, with respect to which detection and false-alarm rates are reported.

  6. Tooth extraction

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007630.htm Tooth extraction To use the sharing features on this page, please enable JavaScript. A tooth extraction is a procedure to remove a tooth from ...

  7. Ln{sub 1-x}Sr{sub x}MnO{sub 3} (Ln=Pr, Nd, Sm and Gd) as the cathode material for solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Sakaki, Y.; Takeda, Y.; Kato, A.; Imanishi, N.; Yamamoto, O. [Department of Chemistry, Faculty of Engineering, Mie University, Tsu 514-8507 (Japan); Hattori, M.; Iio, M.; Esaki, Y. [Electric Power R and D Center, Chubu Electric Power Company, Nagoya 459-8522 (Japan)

    1999-02-15

    The perovskite type manganite systems, Ln{sub 1-x}Sr{sub x}MnO{sub 3} (Ln=La, Pr, Nd, Sm, and Gd; 0{<=}x{<=}0.5) were studied as the electrode materials for solid oxide fuel cells (SOFC) from the view point of applications to the co-firing process of the electrolyte and electrode at a higher temperature. The reactivity tests with yttria-stabilized zirconia (YSZ) showed that the formation of the pyrochlore Ln{sub 2}Zr{sub 2}O{sub 7} was suppressed for the perovskites having smaller lanthanoids than La, especially for the Pr{sub 1-x}Sr{sub x}MnO{sub 3} and Nd{sub 1-x}Sr{sub x}MnO{sub 3} systems. No reaction product appeared between the Ln{sub 1-x}Sr{sub x}MnO{sub 3} perovskite and YSZ even at a high annealing temperature of 1400C when the lanthanoid elements were Pr, Nd and Sm and the Sr content was around 30% (x=0.3). The adjustment of the thermal expansion rate of Ln{sub 1-x}Sr{sub x}MnO{sub 3} to YSZ needed more Sr substitution with an increase of the atomic number of lanthanoids. The Sr contents, x, showing comparable values with 8m/o YSZ were around x=0.1-0.2 in La{sub 1-x}Sr{sub x}MnO{sub 3}, 0.3 in Pr{sub 1-x}Sr{sub x}MnO{sub 3} and Nd{sub 1-x}Sr{sub x}MnO{sub 3} and more than 0.4 in Sm{sub 1-x}Sr{sub x}MnO{sub 3} and Gd{sub 1-x}Sr{sub x}MnO{sub 3}. The electrical conductivity, which may strongly relate with the polarization of electrode reaction, showed about 200 S/cm at 1000C for all Ln{sub 0.7}Sr{sub 0.3}MnO{sub 3} systems. The polarization measurements as an air electrode showed no significant dependence on the kind of lanthanoid elements. From the viewpoint of the electrode activity, high electrical conductivity, low reactivity and good compatibility with YSZ, Pr{sub 0.7}Sr{sub 0.3}MnO{sub 3} and Nd{sub 0.7}Sr{sub 0.3}MnO{sub 3} are considered to be the most suitable electrode materials for the co-firing process

  8. Synthesis and catalytic activity of Ln(III) complexes with an unsymmetrical Schiff base including multigroups

    Institute of Scientific and Technical Information of China (English)

    YAO; Kemin; (

    2003-01-01

    [1]Elder, R. C., Tridentate and unsymmetrical tetradentate Schiff base ligands from salicylaldehydes and dimeric nickel(II) complexes, Aust. J. Chem., 1978, 31:35-45.[2]Atkins, R., Brewer, G., Kokot, G. et al., Copper(II) and nickel(II) complexesof unsymmetrical tetradentate Schiff base ligand, Inorg. Chem., 1985, 24: 127-134.[3]Meng Qingjin, Wang Ruixue, Bu Xiuren et al., New Ni (II) complexes with mixedtrimeric double Schiff ligands, Chemical Journal of Chinese Universities (in Chinese), 1990, 10: 1126-1130.[4]Yao Kemin, Zhou Wen, Lu Gui et al., Synthesis, mechanism and NMR spectra of lanthanide complexes with a novel unsymmetrical Schiff base, Science in China, Series B, 1999, 42(2): 164-169.[5]Yao Kemin, Li Ning, Huang Qiaohong et al., Synthesis and catalytic activity of novel heteronuclear Ln(III)-Cu(II) complexes with noncyclic polyether-amino acid Schiff base, Science in China, Series B, 1999, 42 (1) : 54-81.[6]Li Ning, Yao Kemin, Lou Kaiyan, Synthesis of La(III), Y(III) complexes with polyglycol aldehyde-amino acid Schiff base and their high resolution solid state 13C NMR spectra, Science in China, Series B, 1999, 42(6): 599-604.[7]Lam Berf, J. B., Shurvell, H. F., Verbet, L. et al., Organic Structural Analysis, New York: Macmillan Publishing Co. Inc., 1975, 234-250.[8]Yao Kemin, Cai Lezhen, Shen Liangfang et al., Synthesis and characterization of lanthanide perchlorates with noncyclic polyethylene glycols and their 13C-NMRspectra, Polyhedron, 1992,11(7): 2245-2251.[9]Dewar, M. J. S., Zoebisch, E. G., Healy, E. F., AM1: A new general purpose quantum mechanical molecular model, J. Amer. Chem. Soc., 1985, 107: 3902-3909.[10]Feifer, P., Avnjr, D., Chemistry in noninteger dimensions between two and three, I. Fractal theory of heterogeneous surfaces, J. Chem. Phys., 1983, 79(7): 3558-3565.[11]Yang Haifeng, Wang Hui, Duan Jinxia et al., Ab initio research of organic ligand Schiff base 4-[(2-hydroxyphenyl) imine]-2

  9. Carbonato-bridged Ni(II)2Ln(III)2 (Ln(III) = Gd(III), Tb(III), Dy(III)) complexes generated by atmospheric CO2 fixation and their single-molecule-magnet behavior: [(μ4-CO3)2{Ni(II)(3-MeOsaltn)(MeOH or H2O)Ln(III)(NO3)}2]·solvent [3-MeOsaltn = N,N'-bis(3-methoxy-2-oxybenzylidene)-1,3-propanediaminato].

    Science.gov (United States)

    Sakamoto, Soichiro; Fujinami, Takeshi; Nishi, Koshiro; Matsumoto, Naohide; Mochida, Naotaka; Ishida, Takayuki; Sunatsuki, Yukinari; Re, Nazzareno

    2013-06-17

    Atmospheric CO2 fixation of [Ni(II)(3-MeOsaltn)(H2O)2]·2.5H2O [3-MeOsaltn = N,N'-bis(3-methoxy-2-oxybenzylidene)-1,3-propanediaminato], Ln(III)(NO3)3·6H2O, and triethylamine occurred in methanol/acetone, giving a first series of carbonato-bridged Ni(II)2Ln(III)2 complexes [(μ4-CO3)2{Ni(II)(3-MeOsaltn)(MeOH)Ln(III)(NO3)}2] (1Gd, 1Tb, and 1Dy). When the reaction was carried out in acetonitrile/water, it gave a second series of complexes [(μ4-CO3)2{Ni(II)(3-MeOsaltn)(H2O)Ln(III)(NO3)}2]·2CH3CN·2H2O (2Gd, 2Tb, and 2Dy). For both series, each Ni(II)2Ln(III)2 structure can be described as two di-μ-phenoxo-bridged Ni(II)Ln(III) binuclear units bridged by two carbonato CO3(2-) units to form a carbonato-bridged (μ4-CO3)2{Ni(II)2Ln(III)2} structure. The high-spin Ni(II) ion has octahedral coordination geometry, and the Ln(III) ion is coordinated by O9 donor atoms from Ni(II)(3-MeOsaltn), bidentate NO3(-), and one and two oxygen atoms of two CO3(2-) ions. The NO3(-) ion for the first series roughly lie on Ln-O(methoxy) bonds and are tilted toward the outside, while for the second series, the two oxygen atoms roughly lie on one of the Ln-O(phenoxy) bonds due to the intramolecular hydrogen bond. The temperature-dependent magnetic susceptibilities indicated a ferromagnetic interaction between the Ni(II) and Ln(III) ions (Ln(III) = Gd(III), Tb(III), Dy(III)) for all of the complexes, with a distinctly different magnetic behavior between the two series in the lowest-temperature region due to the Ln(III)-Ln(III) magnetic interaction and/or different magnetic anisotropies of the Tb(III) or Dy(III) ion. Alternating-current susceptibility measurements under the 0 and 1000 Oe direct-current (dc) bias fields showed no magnetic relaxation for the Ni(II)2Gd(III)2 complexes but exhibited an out-of-phase signal for Ni(II)2Tb(III)2 and Ni(II)2Dy(III)2, indicative of slow relaxation of magnetization. The energy barriers, Δ/kB, for the spin flipping were estimated from the Arrhenius

  10. Effect of solvent on luminescence properties of re-dispersible LaF3∶Ln3+ (Ln3+=Eu3+,Dy3+,Sm3+ and Tb3+) nanoparticles

    Institute of Scientific and Technical Information of China (English)

    Ganngam Phaomei; W.Rameshwor Singh

    2013-01-01

    LaF3∶Ln3+ (Eu3+,Dy3+,Sm3+ and Tb3+) nanoparticles were prepared in different solvents such as water,EG (ethylene glycol),DMSO (dimethyl sulfoxide) and their mixed solvents at a relatively low temperature of 150 ℃ by simple chemical route.All the prepared samples showed hexagonal phase and exhibited spherical morphology.The highest luminescence intensity was observed for the samples prepared in EG than the samples prepared in other solvents.However,the sample prepared in water showed anomalously higher luminescence intensity than that of the sample prepared in DMSO.

  11. AN UNUSUALLY LONG MECKEL’S DIVERTICULUM

    Directory of Open Access Journals (Sweden)

    Sunil Kumar

    2013-05-01

    Full Text Available ABSTRACT: Meckel’s diverticulum is the most common congenita l abnormality of the gastrointestinal tract. It is the common differenti al diagnosis thought of in cases of lower abdomen pain especially in Appendicitis. When present, Meck el’s diverticulum is around 2-5cm and its lifetime risk of complications is approximately 4-6 %. Though an entity called ‘Giant Meckel’s diverticulum’ is described in some studies, there a re controversies about length or the width of the diverticulum to be considered for calling it a ‘gia nt’. Usually Meckel’s diverticulum is directed towards umbilicus or anterior abdominal wall due to its embryological origin. There are various ways of presentation of Meckel’s diverticulum and p re-operative diagnosis is difficult except when suspected in cases of bleeding, or when ectopic muc osa is present. Intra-operatively diagnosed Meckel’s diverticulum is treated mainly by resectio n, though the controversies arise for the treatment of co-incidentally found diverticula. We present a case of unusually long Meckel’s diverticulum with its tip attached to root of mesen tery and causing strangulation of ileal loops underneath it.

  12. Extraordinary photons with unusual angular momentum

    Institute of Scientific and Technical Information of China (English)

    YAO ZhiXin; ZHONG JianWei; MAO BangNing; PAN BaiLiang

    2009-01-01

    A series of novel state-vector functions (SVFs), which is the general solution of the Schrodinger equation for a photon, are constructed. Each set of these functions consists of a triplet of eigen-SVFs: The triplet can be broken down into a pair of nonzero/-order functions and a single zero-order function. The photons, described with a triplet of eigen-SVFs, possess all the quantum characteristics of a photon: In addition to common attributes like energy E=hω, and momentum Pz= hk; they also exhibit different angular momenta (AM) Lz+=Ih, Lz-= Ih, and Lz0=0, where I≥1. In other words, in addition to usual eigenvalues Lz±=±h, there are unusual nonzero/-order eigenvalues Lz±=±Ih and a zero-order eigenvalue Lz0 =0 for AM of a photon. By a series of SVFs, the pattern from nonzero /-order and zero-order Laguerre-Gaussian modes of a laser beam is explained well from a quantum mechanical point of view.

  13. How unusual was autumn 2006 in Europe?

    CERN Document Server

    Van Oldenborgh, G J

    2007-01-01

    The temperatures in large parts of Europe have been record high during the meteorological autumn of 2006. Compared to 1961-1990, the 2m temperature was more than three degrees Celsius above normal from the North side of the Alps to southern Norway. This made it by far the warmest autumn on record in the United Kingdom, Belgium, the Netherlands, Denmark, Germany and Switzerland, with the records in Central England going back to 1659, in the Netherlands to 1706 and in Denmark to 1768. Assuming that the mean of the temperature distribution changes proportional to the global mean temperature, but the shape remains the same includes to first order the effects of global warming. Even under this assumption the autumn temperatures were very unusual, with estimates of the return time of 200 to 2000 years in this region. The lower bound of the 95% confidence interval is more than 100 to 300 years. Climate models that simulate the current atmospheric circulation well underestimate the observed mean rise in autumn temper...

  14. Unusual tomographic findings of complicated necrotizing pancreatitis

    Directory of Open Access Journals (Sweden)

    Rosa Maria Silveira Sigrist

    2013-12-01

    Full Text Available Acute pancreatitis (AP is a potential life-threatening disease, which originates from inflammatory involvement of the pancreas and surrounding tissues. Serious complications eventuate and treatment is difficult. AP is classified in both interstitial edematous pancreatitis, which occurs in 70-80% of patients, and necrotizing pancreatitis, which occurs in 20-30% of patients. Diagnosis is based on the presence of two of the following criteria: abdominal pain, increased serum determination of amylase and/or lipase more than three times the reference value, and characteristic tomographic findings. Among the latter, there is the pancreatic and surrounding tissue damage as well as that related to distant organ involvement. This case report shows the fatal case of a male patient with a history of heavy alcoholic abuse admitted with the diagnosis of necrotizing pancreatitis. The authors call attention to the unusual tomographic findings; namely, a huge duodenal hematoma and a large hemoperitoneum, ischemic involvement of the spleen and kidneys, as well as pancreatic and peripancreatic necrosis.

  15. Controlled Unusual Stiffness of Mechanical Metamaterials.

    Science.gov (United States)

    Lee, Wooju; Kang, Da-Young; Song, Jihwan; Moon, Jun Hyuk; Kim, Dongchoul

    2016-02-03

    Mechanical metamaterials that are engineered with sub-unit structures present unusual mechanical properties depending on the loading direction. Although they show promise, their practical utility has so far been somewhat limited because, to the best of our knowledge, no study about the potential of mechanical metamaterials made from sophisticatedly tailored sub-unit structures has been made. Here, we present a mechanical metamaterial whose mechanical properties can be systematically designed without changing its chemical composition or weight. We study the mechanical properties of triply periodic bicontinuous structures whose detailed sub-unit structure can be precisely fabricated using various sub-micron fabrication methods. Simulation results show that the effective wave velocity of the structures along with different directions can be designed to introduce the anisotropy of stiffness by changing a volume fraction and aspect ratio. The ratio of Young's modulus to shear modulus can be increased by up to at least 100, which is a 3500% increase over that of isotropic material (2.8, acrylonitrile butadiene styrene). Furthermore, Poisson's ratio of the constituent material changes the ratio while Young's modulus does not influence it. This study presents the promising potential of mechanical metamaterials for versatile industrial and biomedical applications.

  16. Pyomyositis of Obturator Muscles: Unusual Late Presentation

    Directory of Open Access Journals (Sweden)

    Prasad Channappa Soraganvi

    2013-04-01

    Full Text Available Introduction: Pyomyositis of obturator muscles is rare condition. Late presentation with deformities of hip misleads the clinician. Late presentation (6 weeks of this condition has not been reported earlier. This report highlights this unusual presentation of Pyomyositis of the obturator muscles. Case Report: We are reporting a 14year old female patient presented with limp and pain in hip since 6 weeks. Her hip radiographs were unremarkable. Patient was admitted and MRI done. MRI findings were consistent with obturator pyomyositis. Diagnosis of pyomyositis confirmed by MRI and we performed percutaneous aspiration and drained about 25ml of purulent material mixed with blood. The culture grew Staphylococcus aureus. Patient received intravenous antibiotic for 1week and oral antibiotic for 2weeks. Patient was immobilized in fixed skin traction in Thomas splint for 5days, later gentle mobilization was started. Her condition improved dramatically after aspiration. A follow up MRI done at 3 weeks following aspiration revealed a significant reduction in intramuscular collection of obturator internus and obturator externus. Three weeks following aspiration patient was relieved of the pain and was able to walk normally. At 6 months follow up visit patient was asymptomatic. Conclusion: Late presentation of obturator pyomyositis is rare. We emphasise on careful examination and need for early imaging for diagnosis. Percutaneous drainage results in successful treatment. Keywords: Pyomyositis, septic arthritis, infection, obturator muscle.

  17. Some unusual electronic patterns on graphite surface

    Indian Academy of Sciences (India)

    Shyam K Choudhury; Anjan K Gupta

    2008-02-01

    We report on the observation of some unusual electronic patterns on a graphite surface using scanning tunneling spectroscopy (STM). We attribute these patterns to different types of strain near the surface. One such pattern seen on a particular layer comprises of two-dimensional spatially varying super-lattice and one-dimensional fringes. This pattern is present in a finite region of a layer on the surface confined between two carbon fibers. We attribute this spatially varying super-lattice structure to the shear strain generated in the top layer due to the restraining fibers. We have also developed a model with the Moirµe rotation hypothesis that gives us a better insight into such large-scale spatially varying patterns. We have been able to model the above-observed pattern. We also report another pattern near a defect, which we attribute to the change in density of states due to the physical buckling of the top graphite layer. Part of this buckled layer is found to be buried under another layer and this region shows a reversed contrast and thus supporting our idea of buckling. We also performed tunneling spectroscopy measurements on various regions of these patterns which show significant variations in the density of states.

  18. Unusual Cause of Seizure: Pott Puffy Tumor.

    Science.gov (United States)

    Sade, Recep; Polat, Gokhan; Kantarci, Mecit

    2016-09-01

    Seizures is a comparatively common neurologic unwellness in children that has significant implications for development, parents, and society. The etiologic categories of seizures involve idiopathic, symptomatic, and cryptogenic. Pott puff tumor is a rare cause of seizures. The authors present a rare cause of the seizures.A 12-year-old boy presented with seizures. On physical examination there was swelling on his glabella. Laboratory testing indicated leukocytosis and increased C-reactive protein, and microbiological testing showed the presence of pathogenic streptococcus sp. Brain magnetic resonance imaging was performed. T1-weighted image with gadolinium enhancement revealed frontal bone defects and subcutaneous abscess and left frontal swelling. On the diffusion-weighted imaging, the abscess has relatively homogeneous increased signal intensity b1000. The apparent diffusion coefficient map reveals low intensity. Intracranial spread also showed contrast-enhanced image (). Magnetic resonance imaging typically reveals an intracranial abscess.Pott puffy tumor is an unusual clinical existence characterized by osteomyelitis of the frontal bone. The very common symptoms are headache, swelling fever, and nasal discharge. Frontal sinus infection may induce osteomyelitis, subperiosteal, and epidural abscess.

  19. Short report of an unusual ballistic trauma

    Science.gov (United States)

    Inchingolo, Francesco; Tatullo, Marco; Marrelli, Massimo; Inchingolo, Alessio D.; Pinto, Giorgia; Inchingolo, Angelo M.; Dipalma, Gianna

    2011-01-01

    INTRODUCTION Portable firearms have a relevant medico-legal interest, being a major cause of injury. Bullet entry wounds generally have a particular appearance, including contusion, skin introflection, and simple or excoriated ecchymosis. The skin wound is typically a hole with frayed margins, whose diameter is smaller than that of the bullet. PRESENTATION OF CASE We report the case of a 19-year-old man with ballistic trauma. Examination of the patient's lesions indicated that the bullet had entered from the left mandibular parasymphysis, creating a small hole without the typical bullet wipe and blackening. Subsequently, the bullet seemed to have fractured the left chin region immediately below the lower alveolar process, and it finally stopped in the submandibular area in the suprahyoid region of the neck. DISCUSSION This case is peculiar because the distinctive features of a firearm injury were absent; the lack of bleeding and edema made the case difficult to interpret without additional diagnostic investigations. CONCLUSION Ballistic trauma can manifest in different ways; therefore, internal trauma should be suspected even in the absence of clear external signs. This case report shows how an unusual bullet entry hole can mask quite serious injuries. PMID:22096751

  20. More Unusual Light Curves from Kepler

    Science.gov (United States)

    Kohler, Susanna

    2017-03-01

    Twenty-three new objects have been added to the growing collection of stars observed to have unusual dips in their light curves. A recent study examines these stars and the potential causes of their strange behavior.An Influx of DataThe primary Kepler mission provided light curves for over 100,000 stars, and its continuation K2 is observing another 20,000 stars every three months. As we enter an era where these enormous photometric data sets become commonplace Gaia will obtain photometry for millions of stars, and LSST billions its crucial that we understand the different categories of variability observed in these stars.The authors find three different types of light curves among their 23 unusual stars. Scallop-shell curves (top) show many undulations; persistent flux-dip class curves (middle) have discrete triangularly shaped flux dips; transient, narrow dip class curves (bottom) have only one dip that is variable in depth. The authors speculate a common cause for the scallop-shell and persistent flux-dip stars, and a different cause for the transient flux-dip stars. [Stauffer et al. 2017]After filtering out the stars with planets, those in binary systems, those with circumstellar disks, and those with starspots, a number of oddities remain: a menagerie of stars with periodic variability that cant be accounted for in these categories. Some of these stars are now famous (for instance, Boyajians star); some are lesser known. But by continuing to build up this sample of stars with unusual light curves, we have a better chance of understanding the sources of variability.Building the MenagerieTo this end, a team of scientists led by John Stauffer (Spitzer Science Center at Caltech) has recently hunted for more additions to this sample in the K2 data set. In particular, they searched through the light curves from stars in the Oph and Upper Scorpius star-forming region a data set that makes up the largest collection of high-quality light curves for low-mass, pre

  1. Unusual MRI Findings in a Polio Survivor

    Directory of Open Access Journals (Sweden)

    Masaaki Sakamoto

    2016-01-01

    Full Text Available A 63-year-old male consulted our institution due to worsening of right hip pain for approximately one month. The patient had no apparent functional disorders besides rigidity of the right ankle secondary to childhood poliomyelitis. Plain radiographs demonstrated narrowing of the right hip joint space. Magnetic resonance imaging (MRI showed unusual findings in the right gluteus medius muscle, suspecting a malignant musculoskeletal tumor. Further examinations clarified acute inflammation caused by Staphylococcus aureus with no atypia. After treatment, serum inflammatory markers normalized and MRI showed homogeneous fat signal intensity in the muscle, which was consistent with poliomyelitis. Total hip arthroplasty was performed due to progression of osteoarthritis. Intraoperative findings showed flaccidity of the gluteus medius muscle, and histological examination of the specimen also was compatible with poliomyelitis. Postoperatively there was no hip instability and the patient has been able to resume his previous physical activity. To our knowledge, this is the first report regarding polio survivors combined with septic arthritis, and sole MRI examination was unable to lead to the diagnosis. The current patient demonstrates the possibility that the involved muscles in poliomyelitis exist even in asymptomatic regions, which will be helpful for accurate diagnosis and life guidance in polio survivors.

  2. SPIRITS: Uncovering Unusual Infrared Transients with Spitzer

    Science.gov (United States)

    Kasliwal, Mansi M.; Bally, John; Masci, Frank; Cody, Ann Marie; Bond, Howard E.; Jencson, Jacob E.; Tinyanont, Samaporn; Cao, Yi; Contreras, Carlos; Dykhoff, Devin A.; Amodeo, Samuel; Armus, Lee; Boyer, Martha; Cantiello, Matteo; Carlon, Robert L.; Cass, Alexander C.; Cook, David; Corgan, David T.; Faella, Joseph; Fox, Ori D.; Green, Wayne; Gehrz, R. D.; Helou, George; Hsiao, Eric; Johansson, Joel; Khan, Rubab M.; Lau, Ryan M.; Langer, Norbert; Levesque, Emily; Milne, Peter; Mohamed, Shazrene; Morrell, Nidia; Monson, Andy; Moore, Anna; Ofek, Eran O.; O' Sullivan, Donal; Parthasarathy, Mudumba; Perez, Andres; Perley, Daniel A.; Phillips, Mark; Prince, Thomas A.; Shenoy, Dinesh; Smith, Nathan; Surace, Jason; Van Dyk, Schuyler D.; Whitelock, Patricia A.; Williams, Robert

    2017-04-01

    We present an ongoing, five-year systematic search for extragalactic infrared transients, dubbed SPIRITS—SPitzer InfraRed Intensive Transients Survey. In the first year, using Spitzer/IRAC, we searched 190 nearby galaxies with cadence baselines of one month and six months. We discovered over 1958 variables and 43 transients. Here, we describe the survey design and highlight 14 unusual infrared transients with no optical counterparts to deep limits, which we refer to as SPRITEs (eSPecially Red Intermediate-luminosity Transient Events). SPRITEs are in the infrared luminosity gap between novae and supernovae, with [4.5] absolute magnitudes between -11 and -14 (Vega-mag) and [3.6]-[4.5] colors between 0.3 mag and 1.6 mag. The photometric evolution of SPRITEs is diverse, ranging from 7 mag yr-1. SPRITEs occur in star-forming galaxies. We present an in-depth study of one of them, SPIRITS 14ajc in Messier 83, which shows shock-excited molecular hydrogen emission. This shock may have been triggered by the dynamic decay of a non-hierarchical system of massive stars that led to either the formation of a binary or a protostellar merger.

  3. Extraordinary photons with unusual angular momentum

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A series of novel state-vector functions (SVFs), which is the general solution of the Schrdinger equa- tion for a photon, are constructed. Each set of these functions consists of a triplet of eigen-SVFs: The triplet can be broken down into a pair of nonzero l-order functions and a single zero-order function. The photons, described with a triplet of eigen-SVFs, possess all the quantum characteristics of a photon: In addition to common attributes like energy E = hω, and momentum pz = hκ, they also exhibit different angular momenta (AM) Lz+ = lh, Lz- = lh, and Lz0 = 0, where l≥1. In other words, in addition to usual ei- genvalues Lz±= ±h, there are unusual nonzero l-order eigenvalues Lz±= ±lh and a zero-order eigenvalue Lz0 = 0 for AM of a photon. By a series of SVFs, the pattern from nonzero l-order and zero-order La- guerre-Gaussian modes of a laser beam is explained well from a quantum mechanical point of view.

  4. External Otitis: An Unusual Presentation in Neonates

    Directory of Open Access Journals (Sweden)

    Peymaneh Alizadeh Taheri

    2016-01-01

    Full Text Available Acute otitis externa (AOE is an infection of the external auditory canal, the auricle, and the outer surface of the tympanic membrane. Although AOE is one of the most common otologic conditions encountered in pediatric population, it is known to primarily affect children older than 2 years. We report a case of AOE caused by Staphylococcus aureus in a 23-day-old neonate. A 23-day-old female infant presented to our neonatology clinic with irritability and discharge from the right ear. There were yellow otorrhea, mild erythema, and edema of right external ear canal. There was no sign of otitis media on otoscopy. The results of laboratory tests were insignificant. The discharge culture grew colonies of methicillin-sensitive Staphylococcus aureus. After 48 hours of treatment with intravenous cloxacillin, significant improvement was observed. The present case highlights an unusual presentation of staphylococcal infection in a neonate. This is the first case of methicillin-sensitive Staphylococcus aureus otitis externa in an immunocompetent newborn.

  5. Steric effects of polymethylene chain of 4-acylbis(pyrazolones) on the solvent extraction of trivalent lanthanoids: synergistic effect with mono and bifunctional neutral organophosphorus extractants

    Energy Technology Data Exchange (ETDEWEB)

    Pavithran, Rani [Ion-specific Separation Science and Technology Group, Regional Research Laboratory (CSIR), Thiruvananthapuram 695 019 (India); Reddy, M.L.P. [Ion-specific Separation Science and Technology Group, Regional Research Laboratory (CSIR), Thiruvananthapuram 695 019 (India)]. E-mail: mlpreddy@yahoo.co.uk

    2005-04-22

    Various 4-acylbis(pyrazolones), namely 4-adipoylbis(1-phenyl-3-methyl-5-pyrazolone) (H{sub 2}AdBP = 1), 4-suberoylbis(1-phenyl-3-methyl-5-pyrazolone) (H{sub 2}SuBP = 2), 4-sebacoylbis(1-phenyl-3-methyl-5-pyrazolone) (H{sub 2}SbBP = 3), 4-dodecandioylbis(1-phenyl-3-methyl-5-pyrazolone) (H{sub 2}DdBP = 4) have been synthesized and examined their solvent extraction behavior towards trivalent lanthanoids (Nd{sup 3+}, Eu{sup 3+} and Tm{sup 3+}). The extraction of Ln{sup 3+} ions was found to increase monotonically with increasing atomic number of these metal ions. 1-4 reagents showed an initial increase in the extraction efficiency of Ln{sup 3+} ion with increasing polymethylene chain length, -(CH{sub 2}){sub n}-, from n = 4 to 8 and thereafter a decreasing trend, for n = 10. The equilibrium constants (K{sub ex}) of the extracted complexes have been deduced by nonlinear regression analysis with the aid of suitable chemically based model developed by taking into account chemical mass action principles. The K{sub ex} values were correlated with the polymethylene chain length, by measuring the distance between the carbonyl oxygen atoms connected to the polymethylene chain with the help of semi-empirical PM3 molecular modelling calculations. The synergistic effect on the addition of various neutral organophosphorus extractants to the metal-chelate system has also been investigated. Not only enhanced extraction efficiency, but also improved selectivity has been observed among these Ln{sup 3+} ions. The equilibrium constants of the synergistically extracted complexes have been correlated with the donor ability of the phosphoryl oxygen of the neutral organophosphorus extractants in terms of their {sup 31}P NMR chemical shifts and their basicity values (K{sub H} = nitric acid uptake constant)

  6. Inovační paradox a regionální inovační strategie

    Directory of Open Access Journals (Sweden)

    Skokan Karel

    2010-12-01

    Full Text Available Konkurenceschopnost firem, regionů i států je určována úrovní produktivity, s jakou využívají alokované zdroje, přitom jedním z hlavních faktorů zvyšování produktivity a konkurenceschopnosti jsou inovace. Současný pohled na inovace je založen na systémovém přístupu, podle kterého firmy neinovují izolovaně, ale v interakci s dalšími účastníky inovačních procesů. Teorie systémů inovací se stala jedním z hlavních východisek k porozumění znalostní společnosti, ale také nerovnoměrností ekonomického rozvoje v zaostalých regionech, které se dají vysvětlit pomocí tzv. inovačního paradoxu. Podle něj se zejména na regionální úrovni projevuje nesoulad mezi nabídkou a poptávkou po finančních zdrojích a nabízených a poskytovaných službách při tvorbě a využívání znalostí na podporu inovací. Příčinou je nízká regionální kapacita tyto znalosti, fondy i služby využívat. Řešením se zdají být regionální inovační strategie, s jejichž podporou začala EU již v 90. letech. Cíl předkládaného článku je dvojí. V teoretické části objasňuje principy systémů inovací a inovačního paradoxu, jehož řešením je rozpracování regionálních inovačních strategií. Ve druhé části analyzuje a shrnuje přístup k regionálním inovačním strategiím v EU a v Česku v posledním desetiletí. Vyvozuje, že formální dokumenty inovačních strategií nemusí být nezbytnou podmínkou rozvoje systémů inovací.

  7. Co(II)4, Co(II)7, and a Series of Co(II)2Ln(III) (Ln(III) = Nd(III), Sm(III), Gd(III), Tb(III), Dy(III)) Coordination Clusters: Search for Single Molecule Magnets.

    Science.gov (United States)

    Modak, Ritwik; Sikdar, Yeasin; Thuijs, Annaliese E; Christou, George; Goswami, Sanchita

    2016-10-03

    We report herein the syntheses and investigation of the magnetic properties of a Co(II)4 compound, a series of trinuclear Co(II)2Ln(III) (Ln(III) = Nd(III), Sm(III), Gd(III), Tb(III), Dy(III)) complexes, and a Co(II)7 complex. The homometallic Co(II)4 core was obtained from the reaction of Ln(NO3)3·xH2O/Co(NO3)2·6H2O/H2vab/Et3N in a 0.5:0.5:1:2 ratio in methanol. Variation in synthetic conditions was necessary to get the desired Co(II)-Ln(III) complexes. The Co(II)-Ln(III) assembly was synthesized from Ln(NO3)3·xH2O/Co(OAc)2·4H2O/H2vab/NaOMe in a 0.4:0.5:1:1 ratio in methanol. The isostructural Co(II)2Ln(III) complexes have a core structure with the general formula [Co2Ln(Hvab)4(NO3)](NO3)2·MeOH·H2O, (where H2vab = 2-[(2-hydroxymethyl-phenylimino)-methyl]-6-methoxy-phenol) with simultaneous crystallization of Co(II)7 complex in each reaction. The magnetic investigation of these complexes reveals that both homometallic complexes and four Co(II)-Ln(III) complexes (except Co(II)-Nd(III)) display behavior characteristic of single molecule magnets.

  8. Evaluation of DC electric field distribution of PPLP specimen based on the measurement of electrical conductivity in LN2

    Science.gov (United States)

    Hwang, Jae-Sang; Seong, Jae-Kyu; Shin, Woo-Ju; Lee, Jong-Geon; Cho, Jeon-Wook; Ryoo, Hee-Suk; Lee, Bang-Wook

    2013-11-01

    High temperature superconducting (HTS) cable has been paid much attention due to its high efficiency and high current transportation capability, and it is also regarded as eco-friendly power cable for the next generation. Especially for DC HTS cable, it has more sustainable and stable properties compared to AC HTS cable due to the absence of AC loss in DC HTS cable. Recently, DC HTS cable has been investigated competitively all over the world, and one of the key components of DC HTS cable to be developed is a cable joint box considering HVDC environment. In order to achieve the optimum insulation design of the joint box, analysis of DC electric field distribution of the joint box is a fundamental process to develop DC HTS cable. Generally, AC electric field distribution depends on relative permittivity of dielectric materials but in case of DC, electrical conductivity of dielectric material is a dominant factor which determines electric field distribution. In this study, in order to evaluate DC electric field characteristics of the joint box for DC HTS cable, polypropylene laminated paper (PPLP) specimen has been prepared and its DC electric field distribution was analyzed based on the measurement of electrical conductivity of PPLP in liquid nitrogen (LN2). Electrical conductivity of PPLP in LN2 has not been reported yet but it should be measured for DC electric field analysis. The experimental works for measuring electrical conductivity of PPLP in LN2 were presented in this paper. Based on the experimental works, DC electric field distribution of PPLP specimen was fully analyzed considering the steady state and the transient state of DC. Consequently, it was possible to determine the electric field distribution characteristics considering different DC applying stages including DC switching on, DC switching off and polarity reversal conditions.

  9. Synthesis and novel luminescence properties of one-dimension BaMoO{sub 4}:Ln{sup 3+} nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuping; Li, Mingxia; Pan, Kai; Wang, Guofeng, E-mail: wanggf_w@163.com

    2015-12-15

    Highlights: • String BaMoO{sub 4}:Ln{sup 3+} nanobeans were prepared by a hydrothermal method. • The Decay dynamics were performed to study the photoluminescence of the BaMoO{sub 4}:Eu{sup 3+} nanobeans. • For BaMoO{sub 4}:Er{sup 3+}/Eu{sup 3+}, the {sup 2}P{sub 3/2} → {sup 4}I{sub 11/2} and {sup 2}H{sub 11/2}/{sup 4}S{sub 3/2} → {sup 4}I{sub 15/2} transitions were observed. - Abstract: String BaMoO{sub 4}:Ln{sup 3+} (Ln = Eu, Tb, Er, and Gd) nanobeans were prepared by a hydrothermal method. The samples were characterized by transmission electron microscope, scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscope, and Raman spectrometer. Under direct excitation in the charge transfer absorption band, concentration quenching phenomenon occurs and decay dynamics were performed to study the photoluminescence of the string BaMoO{sub 4}:Eu{sup 3+} nanobeans. In the emission spectra of BaMoO{sub 4}:Er{sup 3+}/Eu{sup 3+} under 274 nm excitation, the {sup 2}P{sub 3/2} → {sup 4}I{sub 11/2}, {sup 2}H{sub 11/2} → {sup 4}I{sub 15/2}, and {sup 4}S{sub 3/2} → {sup 4}I{sub 15/2} transitions from Er{sup 3+} ions were observed for the first time. In addition, the photoluminescence properties of BaMoO{sub 4}:Tb{sup 3+}/Eu{sup 3+} and BaMoO{sub 4}:Gd{sup 3+}/Eu{sup 3+} were also investigated.

  10. Amoeboma- An Interesting Case Report With an Unusual Presentation

    Directory of Open Access Journals (Sweden)

    Vijayshankar S

    2010-10-01

    Full Text Available Amebiasis is an infectious disease caused by Entamoeba Histolytica is more common in devolping countries, with various clinical manifestations and sequalae. Amoeboma , is an unusual sequelae which manifests as a tumor like mass within the colon. We present an unusual case of 5 year old child with signs of acute abdomen. A mass was found on expoloratory laparotomy attached to the small intestine. Histopathological examination of the mass revealed numerous amoebic trophozoites and the diagnosis of amoeboma was made. Our case is unusual because amoebomas presenting as an extraluminal mass attached to small intestine is extremely uncommon.

  11. The Investigation on Welding Processes for SUS316LN Tubes Used in Superconducting Magnetic System of EAST

    Institute of Scientific and Technical Information of China (English)

    Wu Jiefeng; Chen Siyue; Weng Peide; Gao Daming

    2005-01-01

    The force flow cooled superconducting cable-in-conduit conductor (CICC) is used in both of EAST toroidal field (TF) and poloidal field (PF) coils. The conductor consists of multi-stage NbTi superconducting cable and 1.5 mm thick square jacket. The cable is pulled through in a thin wall circular jacket and then compacted to square cross-section conductor. The jacket material is SUS316LN austenitic stainless steel seamless tubes (about 10 m each), which is assembled by butt-welding up to 600 m. The results of the welding procedure investigation and quality assurance procedures carrying out are described in this paper.

  12. Reaction of (CP(2)asterisk-lnH)(2) (ln=Y, La) and CP(2)asterisk-Y(2-C(6)H(4)CH(2)NMe(2)) with esters and amides and molecular-structure of [CP(2)asterisk-Y(mu- ocme=chc(oet)o)](2)

    NARCIS (Netherlands)

    Deelman, B.J; Wierda, F.; Meetsma, A.; Teuben, J.H

    1995-01-01

    The activation of esters and amides by (Cp(2)*LnH)(2) [Ln = Y (1a), Ln = La (1b), Cp*=C(5)Me] and Cp(2)*Y(2-C(6)H(4)CH(2)NMe(2)) (2) is described. Compounds 1a and 1b react with ethyl acetate to form Cp(2)*YOEt (3a) and Cp(2)*LaOEt (30). With 1a and ethyl benzoate a 1:1 mixture of 3a and Cp(2)*YOCH(

  13. Préparation et caractérisation d'oxynitrures Ln2W(O, N) 6- x à structure fluorine déficitaire

    Science.gov (United States)

    Marchand, R.; Antoine, P.; Laurent, Y.

    1993-11-01

    L'action de l'ammoniac sur les tungstates de lanthanides Ln2 WO 6 à 800°C permet de préparer une nouvelle famille d'oxynitrures à structure fluorine déficitaire, de formule Ln2W(O, N) 6- x ( Ln = Nd → Yb, Y). Leur composition générale de type A4X6.6 est intermédiaire entre la stoechiométrie de la fluorine CaF 2( A4X8) et celle de la bixbyite Mn 2O 3( A4X6) qui en dérive. La maille cristalline est cubique avec un paramètre, fonction de la taille du lanthanide, compris entre 5,16 et 5,39 Å. L'étude cristallochimique démontre que les atomes de lanthanide et de tungstène occupent une même position cristallographique. New oxynitrides corresponding to the general formulation Ln2 W(O,N) 6- x ( Ln = Nd → Yb, Y) have been prepared by reaction at 800°C between ammonia and Ln2 WO 6 tungstates, and characterized as defect fluorite type compounds. Their general composition A4X6.6 is intermediate between the Ca F 2( A4X8) fluorite and Mn 2O 3( A4X6) bixbyite stoichiometries. The parameter of the cubic unit cell, comprised between 5.16 and 5.39 Å, depends on the size of the lanthanide. Ln and W atoms occupy a same crystallographic position.

  14. Partnew - New solvent extraction processes for minor actinides - final report; Partnew - Nouveaux procedes d'extraction par solvant pour les actinides mineurs - rapport final

    Energy Technology Data Exchange (ETDEWEB)

    Madic, C.; Testard, F.; Hudson, M.J.; Liljenzin, J.O.; Christiansen, B.; Ferrando, M.; Facchini, A.; Geist, A.; Modolo, G.; Gonzalez-Espartero, A.; Mendoza, J. de

    2004-07-01

    The objectives of the European project PARTNEW were to define solvent extraction processes for the partitioning of the minor actinides, Am and Cm, from the aqueous high active raffinate or high active concentrate issuing the reprocessing of nuclear spent fuels by the PUREX process. Eleven laboratories participated to the research: 1/ CEA-DEN (Marcoule), 2/ CEA-DSM (Saclay), 3/ UREAD (U.K.), 4/ CTU (Sweden), 5/ ITU (Germany), 6/ ENEA (Italy), 7/ PoliMi (Italy), 8/ FZK-INE (Germany), 9/ FZJ-ISR (Germany), 10/ CIEMAT (Spain) and 11/ UAM (Spain). The research was organised into eight work packages (WP): Basic and applied DIAMEX studies, using diamide extractants for the co-extraction of actinides(III) (An(III)) and lanthanides(III) (Ln(III)) nitrates (WP1 and WP2), Basic and applied SANEX studies based on the use of polydentate N-ligands for the An(III)/Ln(III) separation (WP3 and WP4), Basic and applied SANEX studies based on the use of synergistic mixtures made of bis-(chloro-phenyl)-di-thio-phosphinic acid + neutral O-bearing ligand, (WP5 and WP6), Basic SANEX studies for the An(III)/Ln(III) separation, based on the use of new S-bearing ligands, Basic and applied studies for the Am(III)/Cm(III) separation. The work done in the fundamental and applied domains was very fruitful. Several processes have been successfully tested with genuine high active raffinates and concentrate. (authors)

  15. Synthesis and Crystal Structure of [Cp2Ln(OC(SEt)NPh )]2

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chun-Mei; LIU Rui-Ting; ZHOU Xi-Geng

    2006-01-01

    Treatment of Cp3Y with EtSH, followed by reaction with an equivalent of PhNCO, yielded the dinuclear complex [Cp2Y(μ-η1:η3-OC(SEt)NPh )]2. The structure was characterized by elemental analysis, IR, MS and single-crystal X-ray diffraction analysis. The title compound crysta- llizes in triclinic, space group P(1-) with a = 8.643(3), b = 10.752(4), c = 11.161(4)(A), α= 117.840(5), β= 94.086(5),γ= 101.008(5)°, V = 884.8(6)(A)3, Z = 1, Mr = 798.66 (C38H40N2O2S2Y2), λ(MoKα) = 0.710730(A),μ= 3.417 mm-1, Dc = 1.499 g/cm3, F(000) = 408, the final R = 0.0453 and wR = 0.1007 for 3067 unique reflections (Rint = 0.0317) with 2357 observed ones (I >2σ(I)). X-ray analysis reveals an unusual bonding mode of the OC(SEt)NPh ligand and the OCN fragment acts as a both bridging and side-on chelating ligand. Each yttrium atom is coordinated by two η5-cyclopentadienyl groups, one chelating η3-OC(SEt)NPh ligand and one bridging O atom from another η3-OC(SEt)NPh ligand.

  16. Building an Unusual White-Dwarf Duo

    Science.gov (United States)

    Kohler, Susanna

    2016-09-01

    A new study has examined how the puzzling wide binary system HS 2220+2146 which consists of two white dwarfs orbiting each other might have formed. This system may be an example of a new evolutionary pathway for wide white-dwarf binaries.Evolution of a BinaryMore than 100 stellar systems have been discovered consisting of two white dwarfs in a wide orbit around each other. How do these binaries form? In the traditional picture, the system begins as a binary consisting of two main-sequence stars. Due to the large separation between the stars, the stars evolve independently, each passing through the main-sequence and giant branches and ending their lives as white dwarfs.An illustration of a hierarchical triple star system, in which two stars orbit each other, and a third star orbits the pair. [NASA/JPL-Caltech]Because more massive stars evolve more quickly, the most massive of the two stars in a binary pair should be the first to evolve into a white dwarf. Consequently, when we observe a double-white-dwarf binary, its usually a safe bet that the more massive of the two white dwarfs will also be the older and cooler of the pair, since it should have formed first.But in the case of the double-white-dwarf binary HS 2220+2146, the opposite is true: the more massive of the two white dwarfs appears to be the younger and hotter of the pair. If it wasnt created in the traditional way, then how did this system form?Two From Three?Led by Jeff Andrews (Foundation for Research and Technology-Hellas, Greece and Columbia University), a team of scientists recently examined this system more carefully, analyzing its spectra to confirm our understanding of the white dwarfs temperatures and masses.Based on their observations, Andrews and collaborators determined that there are no hidden additional companions that could have caused the unusual evolution of this system. Instead, the team proposed that this unusual binary might be an example of an evolutionary channel that involves three

  17. Unusually severe case of dermatosis neglecta.

    Science.gov (United States)

    Turrentine, Jake E; Blalock, Travis W; Davis, Loretta S

    2012-01-01

    An 18-year-old black woman with cerebral palsy was admitted for evaluation of an intrathecal baclofen pump site infection. The dermatology service was consulted for treatment suggestions of a presumed diagnosis of chronic tinea capitis. Three courses of oral griseofulvin during the past 2 years failed to resolve the patient's chronic scalp dermatosis. Scalp lesions first began about 2 years earlier after hospitalization for placement of an intrathecal baclofen pump. The patient was unable to care for her scalp due to her cerebral palsy, and her mother interpreted the scalp condition as infectious. No routine shampoo care, scalp care, or topical treatment was performed for more than 1 1/2 years. The mother felt that touching the patient's scalp might cause pain and noted that the majority of her time was spent concentrating on more critical medical issues. Physical examination revealed coalescing hyperkeratotic plaques extending dorsally from the anterior hairline to the occipital scalp with small flecks of keratinous debris throughout the remaining hair (Figure 1). The plate-like plaques were devoid of hair, except at a few fissures where a few tufts of hair emerged. No cervical lymph nodes were appreciated on palpation. Treatment was initiated with compresses consisting of large warm water-soaked towels 4 times daily. Three times a day, a nursing staff applied 5% salicylic acid in olive oil to the scalp under a shower cap for approximately 1 hour. Over the following 2 days, a significant reduction in keratinous debris was appreciated. Within 2 weeks, the bulk of the plaques had been removed (Figure 2). At 6-week follow-up, the underlying scalp showed areas of fibrosis and possible scarring with a few emerging tufts of hair. On the basis of history and response to treatment with salicylic acid and routine scalp care, the patient was diagnosed with an unusually severe case of dermatosis neglecta.

  18. How unusual was autumn 2006 in Europe?

    Directory of Open Access Journals (Sweden)

    G. J. van Oldenborgh

    2007-06-01

    Full Text Available The temperatures in large parts of Europe have been record high during the meteorological autumn of 2006. Compared to the 1961–1990 normals it was more than three degrees Celsius warmer from the North side of the Alps to southern Norway. This made it by far the warmest autumn on record in the United Kingdom, Belgium, the Netherlands, Denmark, Germany and Switzerland, with the records in Central England going back to 1659, in the Netherlands to 1706 and in Denmark to 1768. Also in most of Austria, southern Sweden, southern Norway and parts of Ireland the autumn was the warmest on record.

    Under the obviously false assumption that the climate does not change, the observed temperatures for 2006 would occur with a probability of less than once every 10 000 years in a large part of Europe, given the distribution defined by the temperatures in the autumn 1901–2005. However, even taking global warming linearly into account the event was still very unusual, with return times of 200 years or more in most of this region using the most conservative extrapolation.

    Global warming and a southerly circulation were found to give the largest contributions to the anomalous temperature, with minor contributions of more sunshine and SST anomalies in the North Sea. Climate models that simulate the current circulation well do not simulate an increasing probability of warm events in autumn under global warming, implying that it either was a very rare coincidence or some non-linear physics is missing from these models.

  19. Electronic phase separation in the rare-earth manganates (La sub 1 sub - sub x Ln sub x) sub 0 sub . sub 7 Ca sub 0 sub . sub 3 MnO sub 3 (Ln = Nd, Gd and Y)

    CERN Document Server

    Sudheendra, L

    2003-01-01

    Electron transport and magnetic properties of three series of manganates of the formula (La sub 1 sub - sub x Ln sub x) sub 0 sub . sub 7 Ca sub 0 sub . sub 3 MnO sub 3 with Ln = Nd, Gd and Y, wherein only the average A-site cation radius (r sub A ) and associated disorder vary, without affecting the Mn sup 4 sup + /Mn sup 3 sup + ratio, have been investigated in an effort to understand the nature of phase separation. All three series of manganates show saturation magnetization characteristic of ferromagnetism, with the ferromagnetic T sub c decreasing with increasing x up to a critical value of x, x sub c (x sub c = 0.6, 0.3, 0.2 respectively for Nd, Gd, Y). For x > x sub c , the magnetic moments are considerably smaller, showing a small increase around T sub M , the value of T sub M decreasing slightly with increase in x or decrease in (r sub A ). The ferromagnetic compositions (x x sub c are insulating. The magnetic and electrical resistivity behaviour of these manganates is consistent with the occurrence...

  20. Primer caso de hemoglobina Köln (codon98 GTG>ATG en Costa Rica First case of hemoglobin Köln (codon98 GTG>ATG in Costa Rica

    Directory of Open Access Journals (Sweden)

    Walter Cartín

    2010-03-01

    Full Text Available La exposición a ciertos medicamentos puede provocar anemia hemolítica con presencia de cuerpos de Heinz en sangre periférica. Esta anemia puede presentarse por sobredosis de medicamentos, tanto en individuos sanos como en personas con deficiencias enzimáticas como la glucosa-6-fosfato deshidrogenasa, o en presencia de hemoglobinas inestables. Este reporte muestra un caso de anemia hemolítica con cuerpos de Heinz, debido a la presencia de una hemoglobina inestable, cuyos estudios moleculares y HPLC confirmaron el primer caso descrito de hemoglobina Köln (Val98Met en Costa Rica.Exposure to certain drugs may result in hemolytic anemia with the appearance of Heinz-bodies in red blood cells. This type of hemolytic anemia may occur by simple drug overdosage in absence of any known abnormality, such as in normal persons or in patients with erithroid enzyme defects (e.g. G6PD deficiency or unstable hemoglobins.¹ The present report shows a Heinz-body hemolytic anemia because of an abnormal hemoglobin. High pressure liquid chromatography (HPLC and molecular analysis confirmed the first case of Hemoglobin Köln in Costa Rica.

  1. Hydrothermal synthesis and structural characterization of a family of lanthanide tartrates: [Ln 2(C 4H 4O 6) 3(H 2O) 3]·1.5H 2O (Ln = La, Ce, Pr, Nd, Sm)

    Science.gov (United States)

    Athar, Muhammad; Li, Guanghua; Shi, Zhan; Chen, Yan; Feng, Shouhua

    2008-12-01

    Coordination polymers containing lanthanides with tartaric acid [Ln 2(C 4H 4O 6) 3(H 2O) 3]·1.5H 2O (Ln = La, Ce, Pr, Nd, Sm and C 4H 4O 6 = D(-) or L(+) tartrate anion) have been synthesized using hydrothermal techniques and characterized by single crystal X-ray diffraction. The compounds are all isotypic with a monoclinic crystal system in the P2 1/ n space group. The asymmetric units of coordination polymers contain two metal centers having different coordination environments. One metal is bonded to four tartrate groups having three D and one L isomers (or three L and one D isomers), whereas the other metal is bonded to five tartrate groups having two D and three L isomers (or two L and three D isomers). Each trivalent metal center is coordinated to nine oxygen atoms that originate from carboxylate and hydroxyl groups of the tartrate anions and water molecules. These new polymers have three-dimensional structures containing open channels that are occupied by non-coordinating water molecules. Thermogravimetric and differential thermal analyses and adsorption of nitrogen have also been studied for these compounds.

  2. Photoluminescent properties of Eu{sup 3+}, Tb{sup 3+} activated M{sub 3}Ln(PO{sub 4}){sub 3} (M = Sr, Ca; Ln = Y, La, Gd) phosphors derived from hybrid precursors

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Xiuzhen [Department of Chemistry, Tongji University, Shanghai 200092 (China); Xu, Shuai [Department of Chemistry, Tongji University, Shanghai 200092 (China); Yan, Bing [Department of Chemistry, Tongji University, Shanghai 200092 (China)]. E-mail: byan@tongji.edu.cn

    2007-02-21

    Ternary orthophosphates M{sub 3}Ln(PO{sub 4}){sub 3} doped with Eu{sup 3+}, Tb{sup 3+} were prepared via an in situ chemical co-precipitation technology, and the assembly process of hybrid precursors were as follows: using rare-earth coordination polymers with salicylic acid as precursors and composing with the polyvinyl alcohol (PVA) as dispersing media. Their microstructure and micromorphology have been analyzed by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The emission spectra exhibited strong luminescence of {sup 5}D{sub 0} {sup {yields}} {sup 7}F{sub 2} at 609 nm, indicating that the Eu{sup 3+} located in a noncentrosymmetric position in Eu-doped M{sub 3}Ln (PO{sub 4}){sub 3} matrix. Besides this, the values of red to orange emission intensities for Eu{sup 3+} in Sr{sub 3}Gd (PO{sub 4}){sub 3} strongly depend on the doping concentration.

  3. Chemical and structural changes in Ln{sub 2}NiO{sub 4+δ} (Ln=La, Pr or Nd) lanthanide nickelates as a function of oxygen partial pressure at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Flura, Aurélien; Dru, Sophie; Nicollet, Clément; Vibhu, Vaibhav; Fourcade, Sébastien; Lebraud, Eric; Rougier, Aline; Bassat, Jean-Marc; Grenier, Jean-Claude, E-mail: grenier@icmcb-bordeaux.cnrs.fr

    2015-08-15

    The chemical stability of lanthanide nickelates Ln{sub 2}NiO{sub 4+δ} (Ln=La, Pr or Nd) has been studied in the temperature range 25–1300 °C, either in air or at low pO{sub 2} (down to 10{sup −4} atm). Thermal gravimetry analysis (TGA) measurements coupled with X-ray diffraction (XRD) characterization have shown that all compounds retain their K{sub 2}NiF{sub 4}-type structure in these conditions, while remaining over-stoichiometric in oxygen up to 1000 °C. Only Nd{sub 2}NiO{sub 4+δ} starts to decompose into Nd{sub 2}O{sub 3} and NiO above 1000 °C, at pO{sub 2}=10{sup −4} atm. In addition, a careful analysis of the lanthanide nickelates structural features has been performed by in situ XRD, as a function of temperature and pO{sub 2}. For all compounds, a structural transition has been always observed in the temperature range 200–400 °C, in air or at pO{sub 2}=10{sup −4} atm. In addition, their cell volume did not vary upon the variation of the oxygen partial pressure. Therefore, these materials do not exhibit a chemical expansion in these conditions, which is beneficial for a fuel cell application as cathode layers. Additional dilatometry measurements have revealed that a temperature as high as 950 °C for Pr{sub 2}NiO{sub 4+δ} or 1100 °C for La{sub 2}NiO{sub 4+δ} and Nd{sub 2}NiO{sub 4+δ} has to be reached in order to begin the sintering of the material particles, which is of primary importance to obtain an efficient electronic/ionic conduction in the corresponding designed cathode layers. Besides, excellent matching was found between the thermal expansion coefficients of lanthanide nickelates and SOFC electrolytes such as 8wt% yttria stabilized zirconia (8YSZ) or Ce{sub 0.8}Gd{sub 0.2}O{sub 2−δ} (GDC), at least from 400 °C up to 1400 °C in air or up to 1200 °C at pO{sub 2}=10{sup −4} atm. - Graphical abstract: This study reports the good chemical stability of oxygen overstoichiometric Ln2NiO4+δ(Ln = La, Pr or Nd) at high temperatures

  4. What Do Classrooms in Unusually Successful Schools Look Like?

    Science.gov (United States)

    Willis, Charles L.

    Briefly described are classrooms in eight unusually successful elementary schools differing in size, grade levels, racial mix, community size and location, and percentage of low income parents. Most were well equipped, had computers and typewriters, and displayed students' work. (RH)

  5. Diagnostic considerations concerning a case of an unusual gingivitis

    NARCIS (Netherlands)

    van der Haring, I.S.; Witjes, M.J.H.

    2006-01-01

    A young woman presented a severe gingivitis that wouldn't respond to antibiotics prescribed by her general practitioner. Thorough clinical examination showed atypical gingival inflammation. In such unusual cases a careful anamnesis is essential in determining appropriate continued diagnostic

  6. Recurrent seizures: An unusual manifestation of vitamin B12 deficiency

    Directory of Open Access Journals (Sweden)

    Kumar S

    2004-01-01

    Full Text Available The present report highlights an unusual presentation of vitamin B12 deficiency— recurrent seizures in a 26-year-old man. His symptoms responded to parenteral vitamin B12 therapy. The relevant literature is reviewed.

  7. Northern Gulf of Mexico Marine Mammal Unusual Mortality Event Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Tissues and samples collected from marine mammals during investigation of the Northern Gulf of Mexico Marine Mammal Unusual Mortality Event are tracked within this...

  8. Pediatric sciatic neuropathies due to unusual vascular causes

    NARCIS (Netherlands)

    Srinivasan, Jayashri; Escolar, Diane; Ryan, Monique; Darras, Basil; Jones, H. Royden

    2008-01-01

    Four cases of pediatric sciatic neuropathies due to unusual vascular mechanisms are reported. Pediatric sciatic neuropathies were seen after umbilical artery catheterization, embolization of arteriovenous malformation, meningococcemia, and hypereosinophilic vasculitis. Electrophysiologic studies dem

  9. Unusual occurrence of congenital hypothyroidism in a set of same ...

    African Journals Online (AJOL)

    Unusual occurrence of congenital hypothyroidism in a set of same sex triplets: challenges of ... Genetic and intrauterine factors have been implicated in its aetiology. ... On testing for thyroid hormones the patients were found to be hypothyroid.

  10. Enterobius vermicularis in the kidney: an unusual location.

    Science.gov (United States)

    Cateau, Estelle; Yacoub, Mokrane; Tavilien, Christian; Becq-Giraudon, Bertrand; Rodier, Marie-Hélène

    2010-07-01

    A woman was admitted to hospital with abdominal pain. A large kidney stone was recovered and a nephrectomy was performed. Histology revealed the unusual presence of multiple Enterobius vermicularis ova. However, no other parasitic element was recovered on further investigations.

  11. Pediatric sciatic neuropathies due to unusual vascular causes

    NARCIS (Netherlands)

    Srinivasan, Jayashri; Escolar, Diane; Ryan, Monique; Darras, Basil; Jones, H. Royden

    Four cases of pediatric sciatic neuropathies due to unusual vascular mechanisms are reported. Pediatric sciatic neuropathies were seen after umbilical artery catheterization, embolization of arteriovenous malformation, meningococcemia, and hypereosinophilic vasculitis. Electrophysiologic studies

  12. An unusual pressure sore of the nasal bridge.

    Science.gov (United States)

    Sleilati, Fadi H; Stephan, Henri A; Nasr, Marwan W; Riachy, Moussa A

    2008-07-01

    We report an unusual pressure sore of the nasal bridge caused by a non-invasive ventilation mask. Conservative treatment was unsuccessful, and the defect had to be repaired, with a good postoperative result.

  13. An ovary as unusual contents of an incarcerated umbilical hernia.

    Science.gov (United States)

    Ahmed, U; Ahmed, R; Kamat, S; Elkholy, K

    2014-09-01

    We present the unusual case of a woman presenting with an incarcerated umbilical hernia. Intraoperatively, the contents of the hernia were found to be an ovary. We outline the clinical presentation of our patient, investigations and management as well as a discussion on unusual contents of umbilical hernias. To our knowledge, this is the first case of a non-malignant ovary incarcerated in an umbilical hernia.

  14. Pancreatic tumor of mesenchymal origin--an unusual surgical finding.

    Science.gov (United States)

    Peskova, M; Fried, M

    1994-04-01

    Recently, a patient with an unusual pancreatic tumor of smooth muscle origin, presented at the First Surgical Clinic, Charles University Hospital, Prague. Leiomyosarcoma, a malignant smooth muscle tumor, may arise almost anywhere in the body. Pancreatic localization is very unusual. A number of authors have surveyed the literature on pancreatic tumors of mesenchymal origin. As many as fifty cases have been reported in autopsy studies since 1882. Only six operated cases of pancreatic sarcomas were found in surgical series.

  15. Towards Generic Detection of Unusual Events in Video Surveillance

    OpenAIRE

    Ivanov, Ivan; Dufaux, Frederic; Ha, Thien M.; Ebrahimi, Touradj

    2009-01-01

    In this paper, we consider the challenging problem of unusual event detection in video surveillance systems. The proposed approach makes a step toward generic and automatic detection of unusual events in terms of velocity and acceleration. At first, the moving objects in the scene are detected and tracked. A better representation of moving objects trajectories is then achieved by means of appropriate pre-processing techniques. A supervised Support Vector Machine method is then used to train t...

  16. No Laughing Matter: Gelastic Migraine and Other Unusual Headache Syndromes.

    Science.gov (United States)

    Mathew, Paul G; Robertson, Carrie E

    2016-05-01

    Primary and secondary headache disorders have established diagnostic criteria in the International Classification of Headache Disorders IIIb, as well as classic findings, which although not part of the formal criteria are often suggestive of a particular diagnosis. At times, headache disorders can involve unusual symptoms that lack an identifiable secondary cause. This review will discuss some of these unusual symptoms, including headache associated auditory and olfactory symptoms, as well as two case reports involving gelastic migraine and migrainous thoracalgia.

  17. Low Cycle Fatigue Behavior of 316LN Stainless Steel Alloyed with Varying Nitrogen Content. Part I: Cyclic Deformation Behavior

    Science.gov (United States)

    Prasad Reddy, G. V.; Sandhya, R.; Sankaran, S.; Mathew, M. D.

    2014-10-01

    In this study, the influence of cyclic strain amplitude on the evolution of cyclic stress-strain response and the associated cyclic deformation mechanisms in 316LN stainless steel with varying nitrogen content (0.07 to 0.22 wt pct) is reported in the temperature range 773 K to 873 K (500 °C to 600 °C). Two mechanisms, namely dynamic strain aging and secondary cyclic hardening, are found to strongly influence the cyclic stress response. Deformation substructures associated with both the mechanisms showed planar mode of deformation. These mechanisms are observed to be operative over certain combinations of temperature and strain amplitude. For strain amplitudes >0.6 pct, wavy or mixed mode of deformation is noticed to suppress both the mechanisms. Cyclic stress-strain curves revealed both single and dual-slope behavior depending on the test temperature. Increase in nitrogen content is found to increase the tendency toward planar mode of deformation, while increase in strain amplitude leads to transition from planar slip bands to dislocation cell/wall structure formation, irrespective of the nitrogen content in 316LN stainless steel.

  18. Návrh odstředivého čerpadla metodami diferenciální geometrie

    OpenAIRE

    Sloupenský, Zdeněk

    2011-01-01

    Disertační práce se zabývá novým přístupem návrhu oběžného kola, lopatky a spirály odstředivého čerpadla. Matematický model proudění v meridiálním řezu oběžného kola i spirály se opírá o nástroje diferenciální geometrie aplikované na Bézieroy plochy. Tato již dříve představená teorie je v této práci hlouběji rozpracována a závěry jsou využity při návrhu součástí odstředivého čerpadla, které přicházejí do styku s kapalinou. Hlavním výstupem práce je matematický model a na jeho základě vytvořen...

  19. Analytic amplitudes for hadronic forward scattering and the Heisenberg ln{sup 2} s behaviour of total cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Nicolescu, Basarab [LPNHE, Unite de Recherche des Universites Paris 6 et Paris 7, associee au CNRS, Theory Group, Universite Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris Cedex 05 (France)

    2004-07-01

    We consider several classes of analytic parametrizations of hadronic scattering amplitudes (the COMPETE analysis), and compare their predictions to all available forward data (pp, {pi}p, Kp, {gamma}p, {gamma}{gamma}, {sigma}p). Although these parametrizations are very close for {radical}s {>=} 9 GeV, it turns out that they differ markedly at low energy, where a universal Pomeron term {approx} ln{sup 2} s enables one to extend the fit down to {radical}s = 4 GeV. We present predictions on the total cross sections and on the ratio of the real part to the imaginary part of the elastic amplitude ({rho} parameter) for present and future pp colliders, and on total cross sections for {gamma}p {yields} hadrons at cosmic-ray energies and for it{gamma}{gamma} {yields} hadrons up to {radical}s = 1 TeV. The ln{sup 2} s behaviour of total cross sections, first obtained by Heisenberg 50 years ago, receives now increased interest both on phenomenological and theoretical levels. We present a modification of the Heisenberg's model in connection with the presence of glueballs and we show that it leads to a realistic description of all existing hadron total cross-sections data, in agreement with the COMPETE analysis.

  20. Synthesis of Multicolor Core/Shell NaLuF₄:Yb(3+)/Ln(3+)@CaF₂ Upconversion Nanocrystals.

    Science.gov (United States)

    Li, Hui; Hao, Shuwei; Yang, Chunhui; Chen, Guanying

    2017-02-07

    The ability to synthesize high-quality hierarchical core/shell nanocrystals from an efficient host lattice is important to realize efficacious photon upconversion for applications ranging from bioimaging to solar cells. Here, we describe a strategy to fabricate multicolor core @ shell α-NaLuF₄:Yb(3+)/Ln(3+)@CaF₂ (Ln = Er, Ho, Tm) upconversion nanocrystals (UCNCs) based on the newly established host lattice of sodium lutetium fluoride (NaLuF₄). We exploited the liquid-solid-solution method to synthesize the NaLuF₄ core of pure cubic phase and the thermal decomposition approach to expitaxially grow the calcium fluoride (CaF₂) shell onto the core UCNCs, yielding cubic core/shell nanocrystals with a size of 15.6 ± 1.2 nm (the core ~9 ± 0.9 nm, the shell ~3.3 ± 0.3 nm). We showed that those core/shell UCNCs could emit activator-defined multicolor emissions up to about 772 times more efficient than the core nanocrystals due to effective suppression of surface-related quenching effects. Our results provide a new paradigm on heterogeneous core/shell structure for enhanced multicolor upconversion photoluminescence from colloidal nanocrystals.