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Sample records for terbium iodides

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-04-15

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

  2. Elastic properties of terbium

    DEFF Research Database (Denmark)

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

    1996-01-01

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

  3. Critical scattering of neutrons from terbium

    DEFF Research Database (Denmark)

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

    1968-01-01

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

  4. Semiconductor composition containing iron, dysprosium, and terbium

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-09-26

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

  5. Magnetocaloric effect of thin Terbium films

    Science.gov (United States)

    Mello, V. D.; Anselmo, D. H. A. L.; Vasconcelos, M. S.; Almeida, N. S.

    2017-12-01

    We report a theoretical study of the magnetocaloric effect of Terbium (Tb) thin films due to finite size and surface effects in the helimagnetic phase, corresponding to a temperature range from TC=219 K to TN=231 K, for external fields of the order of kOe. For a Tb thin film of 6 monolayers submitted to an applied field (ΔH =30 kOe, ΔH =50 kOe and ΔH = 70 kOe) we report a significative change in adiabatic temperature, ΔT / ΔH , near the Néel temperature, of the order ten times higher than that observed for Tb bulk. On the other hand, for small values of the magnetic field, large thickness effects are found. For external field strength around few kOe, we have found that the thermal caloric efficiency increases remarkably for ultrathin films. For an ultrathin film with 6 monolayers, we have found ΔT / ΔH = 43 K/T while for thicker films, with 20 monolayers, ΔT / ΔH = 22 K/T. Our results suggest that thin films of Tb are a promising material for magnetocaloric effect devices for applications at intermediate temperatures.

  6. Femtosecond XUV spectroscopy of gadolinium and terbium

    Energy Technology Data Exchange (ETDEWEB)

    Carley, Robert; Frietsch, Bjoern; Doebrich, Kristian; Teichmann, Martin; Gahl, Cornelius; Noack, Frank [Max-Born-Institute, Berlin (Germany); Schwarzkopf, Olaf; Wernet, Philippe [Helmholtz-Zentrum fuer Materialien und Energie (BESSY II), Berlin (Germany); Weinelt, Martin [Max-Born-Institute, Berlin (Germany); Fachbereich Physik, Freie Universitaet, Berlin (Germany)

    2011-07-01

    We present recent results of time-resolved IR-pump-XUV-probe experiments on the ultrafast demagnetization of thin films of Gadolinium(0001) and Terbium(0001) on Tungsten(110). The experiments are the first to be done using a newly developed high-order harmonics (HHG) XUV beamline at the MBI. The beamline delivers monochromated XUV pulses of approximately 150 fs duration with a photon energy resolution of up to 150 meV. Following excitation by intense femtosecond infrared (IR) pulses, photoemission with 35 eV photons allows us to directly probe the 4f electrons and their interaction with the valence band, both in the bulk and at the surface, to follow the ultrafast magnetization dynamics in the Lanthanide metals. As signatures of ultrafast demagnetization of the metal by the IR pulse, we see for the first time, rapid strong reduction of the exchange splitting in the valence band. This is followed by a slower demagnetization due to the spin-lattice interaction.

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

    Indian Academy of Sciences (India)

    Glasses; terbium ion; oscillator strengths; fluorescence; lifetimes; fibre lasers. 1. Introduction. Today glasses are most favourable engineering materials for abundant applications due to the wide ability of property altering by compositional modifications. The considerable examination of glass science to achieve required ...

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

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 39; Issue 3. Green fluorescence of terbium ions in lithium fluoroborate glasses for fibre lasers and display devices. G R DILLIP C MADHUKAR REDDY M RAJESH SHIVANAND CHAURASIA B DEVA PRASAD RAJU S W JOO. Volume 39 Issue 3 June 2016 pp 711-717 ...

  9. Strontium Iodide Radiation Instrumentation (SIRI)

    Science.gov (United States)

    Mitchell, Lee J.; Phlips, Bernard F.; Woolf, Richard S.; Finne, Theodore T.; Johnson, W. Neil; Jackson, Emily G.

    2017-08-01

    The Strontium Iodide Radiation Instrumentation (SIRI) is designed to space-qualify new gamma-ray detector technology for space-based astrophysical and defense applications. This new technology offers improved energy resolution, lower power consumption and reduced size compared to similar systems. The SIRI instrument consists of a single europiumdoped strontium iodide (SrI2:Eu) scintillation detector. The crystal has an energy resolution of 3% at 662 keV compared to the 6.5% of traditional sodium iodide and was developed for terrestrial-based weapons of mass destruction (WMD) detection. SIRI's objective is to study the internal activation of the SrI2:Eu material and measure the performance of the silicon photomultiplier (SiPM) readouts over a 1-year mission. The combined detector and readout measure the gammaray spectrum over the energy range of 0.04 - 4 MeV. The SIRI mission payoff is a space-qualified compact, highsensitivity gamma-ray spectrometer with improved energy resolution relative to previous sensors. Scientific applications in solar physics and astrophysics include solar flares, Gamma Ray Bursts, novae, supernovae, and the synthesis of the elements. Department of Defense (DoD) and security applications are also possible. Construction of the SIRI instrument has been completed, and it is currently awaiting integration onto the spacecraft. The expected launch date is May 2018 onboard STPSat-5. This work discusses the objectives, design details and the STPSat-5 mission concept of operations of the SIRI spectrometer.

  10. Iodide uptake by negatively charged clay interlayers?

    Science.gov (United States)

    Miller, Andrew; Kruichak, Jessica; Mills, Melissa; Wang, Yifeng

    2015-09-01

    Understanding iodide interactions with clay minerals is critical to quantifying risk associated with nuclear waste disposal. Current thought assumes that iodide does not interact directly with clay minerals due to electrical repulsion between the iodide and the negatively charged clay layers. However, a growing body of work indicates a weak interaction between iodide and clays. The goal of this contribution is to report a conceptual model for iodide interaction with clays by considering clay mineral structures and emergent behaviors of chemical species in confined spaces. To approach the problem, a suite of clay minerals was used with varying degrees of isomorphic substitution, chemical composition, and mineral structure. Iodide uptake experiments were completed with each of these minerals in a range of swamping electrolyte identities (NaCl, NaBr, KCl) and concentrations. Iodide uptake behaviors form distinct trends with cation exchange capacity and mineral structure. These trends change substantially with electrolyte composition and concentration, but do not appear to be affected by solution pH. The experimental results suggest that iodide may directly interact with clays by forming ion-pairs (e.g., NaI(aq)) which may concentrate within the interlayer space as well as the thin areas surrounding the clay particle where water behavior is more structured relative to bulk water. Ion pairing and iodide concentration in these zones is probably driven by the reduced dielectric constant of water in confined space and by the relatively high polarizability of the iodide species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Terahertz Cherenkov radiation from ultrafast magnetization in terbium gallium garnet

    Science.gov (United States)

    Gorelov, S. D.; Mashkovich, E. A.; Tsarev, M. V.; Bakunov, M. I.

    2013-12-01

    We report an experimental observation of terahertz Cherenkov radiation from a moving magnetic moment produced in terbium gallium garnet by a circularly polarized femtosecond laser pulse via the inverse Faraday effect. Contrary to some existing theoretical predictions, the polarity of the observed radiation unambiguously demonstrates the paramagnetic, rather than diamagnetic, nature of the ultrafast inverse Faraday effect. From measurements of the radiation field, the Verdet constant in the subpicosecond regime is ˜3-10 times smaller than its table quasistatic value.

  12. A perchlorate sensitive iodide transporter in frogs.

    Science.gov (United States)

    Carr, Deborah L; Carr, James A; Willis, Ray E; Pressley, Thomas A

    2008-03-01

    Nucleotide sequence comparisons have identified a gene product in the genome database of African clawed frogs (Xenopus laevis) as a probable member of the solute carrier family of membrane transporters. To confirm its identity as a putative iodide transporter, we examined the function of this sequence after heterologous expression in mammalian cells. A green monkey kidney cell line transfected with the Xenopus nucleotide sequence had significantly greater (125)I uptake than sham-transfected control cells. The uptake in carrier-transfected cells was significantly inhibited in the presence of perchlorate, a competitive inhibitor of mammalian Na(+)/iodide symporter. Tissue distributions of the sequence were also consistent with a role in iodide uptake. The mRNA encoding the carrier was found to be expressed in the thyroid gland, stomach, and kidney of tadpoles from X. laevis, as well as the bullfrog Rana catesbeiana. The ovaries of adult X. laevis also were found to express the carrier. Phylogenetic analysis suggested that the putative X. laevis iodide transporter is orthologous to vertebrate Na(+)-dependent iodide symporters. We conclude that the amphibian sequence encodes a protein that is indeed a functional Na(+)/iodide symporter in X. laevis, as well as R. catesbeiana.

  13. Terbium luminescence in alumina xerogel fabricated in porous anodic alumina matrix under various excitation conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gaponenko, N. V., E-mail: nik@nano.bsuir.edu.by [Belarusian State University of Informatics and Radioelectronics (Belarus); Kortov, V. S. [Yeltsin Ural Federal University (Russian Federation); Orekhovskaya, T. I.; Nikolaenko, I. A. [Belarusian State University of Informatics and Radioelectronics (Belarus); Pustovarov, V. A.; Zvonarev, S. V.; Slesarev, A. I. [Yeltsin Ural Federal University (Russian Federation); Prislopski, S. Ya. [National Academy of Sciences of Belarus, Stepanov Institute of Physics (Belarus)

    2011-07-15

    Terbium-doped alumina xerogel layers are synthesized by the sol-gel method in pores of a porous anodic alumina film 1 {mu}m thick with a pore diameter of 150-180 nm; the film is grown on a silicon substrate. The fabricated structures exhibit terbium photoluminescence with bands typical of trivalent terbium terms. Terbium X-ray luminescence with the most intense band at 542 nm is observed for the first time for such a structure. Morphological analysis of the structure by scanning electron microscopy shows the presence of xerogel clusters in pore channels, while the main pore volume remains unfilled and pore mouths remain open. The data obtained confirm the promising applications of fabricated structures for developing matrix converters of X-rays and other ionizing radiations into visible light. The possibilities of increasing luminescence intensity in the matrix converter are discussed.

  14. Optical Properties of Lithium Terbium Fluoride and Implications for Performance in High Power Lasers (Postprint)

    Science.gov (United States)

    2016-02-01

    AFRL-RX-WP-JA-2016-0323 OPTICAL PROPERTIES OF LITHIUM TERBIUM FLUORIDE AND IMPLICATIONS FOR PERFORMANCE IN HIGH POWER LASERS... AMERICA (STINFO COPY) AIR FORCE RESEARCH LABORATORY MATERIALS AND MANUFACTURING DIRECTORATE WRIGHT-PATTERSON AIR FORCE BASE, OH 45433-7750 AIR...OPTICAL PROPERTIES OF LITHIUM TERBIUM FLUORIDE AND IMPLICATIONS FOR PERFORMANCE IN HIGH POWER LASERS (POSTPRINT) 5a. CONTRACT NUMBER IN-HOUSE 5b

  15. Detection of biothiols in cells by a terbium chelate-Hg (II) system

    Science.gov (United States)

    Tan, Hongliang; Chen, Yang

    2012-01-01

    Great efforts have been devoted to the development of sensitive and specific analysis methods for biothiols because of their important roles in biological systems. We present a new detection system for biothiols that is based on the reversible quenching and restoration of fluorescence of terbium chelate caused by Hg2+ and thiol species. In the presence of biothiols, a restoration of fluorescence of terbium chelate after quenching by Hg2+ was observed due to the interaction of Hg2+ with thiol groups, and the restored fluorescence increased with the concentration of biothiols. This method was sensitive and selective for biothiols. The detection limit was 80 nM for glutathione, 100 nM for Hcy, and 400 nM for Cysteine, respectively. The terbium chelate-Hg (II) system was successfully applied to determine the levels of biothiols in cancer cells and urine samples. Further, it was also shown to be comparable to Ellman's assay. Compared to other fluorescence methods, the terbium chelate probe is advantageous because interference from short-lived nonspecific fluorescence can be efficiently eliminated due to the long fluorescence lifetime of terbium chelate, which allows for detection by time-resolved fluorescence. The terbium chelate probe can serve as a diagnostic tool for the detection of abnormal levels of biothiols in disease.

  16. Kinetics of gold dissolution in iodide solutions

    Science.gov (United States)

    Yang, Kang

    Cyanide has been used as a lixiviant for free milling gold ores for a long time. Cyanide solutions are highly toxic and their use poses long term environmental problems. Cyanidation process is efficient for oxide gold ores but it is ineffective for gold ores containing sulfides. Among the noncyanide based lixiviants, iodide has the potential of replacing cyanide due to its ability to leach gold at a wider pH range and higher rate of gold dissolution. The emerging technology of bio-oxidation is an accepted process for pretreatment of sulfide gold ores. The bio-oxidation is conducted at acidic pH which makes direct cyanidation without pH adjustment impractical. On the contrary, iodide leaching of gold from the bio-oxidized ore can be accomplished without any pH adjustment. The present study was undertaken in order to investigate the kinetics of gold dissolution in various iodide-oxidant solutions under conditions similar to those prevailing in a solution containing bio-oxidized ore. The thermodynamic study indicated that gold can be spontaneously dissolved in iodide-hydrogen peroxide, iodide-ferric ion and iodide-persulfate solutions. Dissolution of gold powder was carried out in these solutions and the results showed that the gold dissolution was dependent on solution pH, concentrations of iodide, oxidants and temperature. Gold dissolution was found to increase with decreasing pH and substantial gold dissolution could be achieved at pH ≤ 2. Increasing concentration of oxidant till an optimum oxidant/iodide molar ratio increased gold dissolution and much higher concentration of oxidant would result in a decrease in gold dissolution. With increasing iodide concentration and temperature, gold dissolution increased significantly. The activation energy data which ranged between 9.6 and 13.6 kcal/mole for various oxidants indicated that surface reaction was the rate controlling step. At higher temperatures a change in rate limiting step with passage of time was observed

  17. Cryogenic temperature characteristics of Verdet constant of terbium sesquioxide ceramics

    Science.gov (United States)

    Snetkov, I. L.; Palashov, O. V.

    2016-12-01

    The dependence of the Verdet constant on temperature in the (80-300 K) range for a promising magneto-active material terbium sesquioxide Tb2O3 at the wavelengths of 405-1064 nm is considered. For each of the studied wavelengths, the Verdet constant of the material cooled down to the liquid nitrogen temperature increased by more than a factor of 3.2 as compared to the room temperature value. Similarly to the other paramagnetics, the increase follows the law ∼1/T. Approximations for the temperature dependence of the Verdet constant have been obtained and the value of 1/V·(dV/dT) has been estimated. This information is needed to determine the angle of rotation as well as the variation of the extinction ratio of a Faraday isolator with temperature and extremely important at creation a cryogenic Faraday devices.

  18. Biogenic terbium oxide nanoparticles as the vanguard against osteosarcoma

    Science.gov (United States)

    Iram, Sana; Khan, Salman; Ansary, Abu Ayoobul; Arshad, Mohd; Siddiqui, Sahabjada; Ahmad, Ejaz; Khan, Rizwan H.; Khan, Mohd Sajid

    2016-11-01

    The synthesis of inner transition metal nanoparticles via an ecofriendly route is quite difficult. This study, for the first time, reports synthesis of terbium oxide nanoparticles using fungus, Fusarium oxysporum. The biocompatible terbium oxide nanoparticles (Tb2O3 NPs) were synthesized by incubating Tb4O7 with the biomass of fungus F. oxysporum. Multiple physical characterization techniques, such as UV-visible and photoluminescence spectroscopy, TEM, SAED, and zeta-potential were used to confirm the synthesis, purity, optical and surface characteristics, crystallinity, size, shape, distribution, and stability of the nanoemulsion of Tb2O3 NPs. The Tb2O3 NPs were found to inhibit the propagation of MG-63 and Saos-2 cell-lines (IC50 value of 0.102 μg/mL) and remained non-toxic up to a concentration of 0.373 μg/mL toward primary osteoblasts. Cell viability decreased in a concentration-dependent manner upon exposure to 10 nm Tb2O3 NPs in the concentration range 0.023-0.373 μg/mL. Cell toxicity was evaluated by observing changes in cell morphology, cell viability, oxidative stress parameters, and FACS analysis. Morphological examinations of cells revealed cell shrinkage, nuclear condensation, and formation of apoptotic bodies. The level of ROS within the cells-an indicator of oxidative stress was significantly increased. The induction of apoptosis at concentrations ≤ IC50 was corroborated by 4‧,6-diamidino-2-phenylindole dihydrochloride (DAPI) staining (DNA damage and nuclear fragmentation). Flow-cytometric studies indicated that the response was dose dependent with a threshold effect.

  19. Kinetic Isotope Effects in the Reduction of Methyl Iodide

    DEFF Research Database (Denmark)

    Holm, Torkil

    1999-01-01

    a-Deuterium kinetic isotope effects (KIE's) have been determined for the reaction of methyl iodide with a series of reducing agents. Reagents which transfer hydride ion in an SN2 reaction show small inverse or small normal KIE's. Reagents which transfer an electron to methyl iodide to produce...... methyl radical show large normal KIE's up to 20 % per a-D. Large KIE's were found for the reaction of methyl iodide with sodium, for Pd-catalyzed reaction of methyl iodide with hydrogen, for ET at a platinum cathode, for ET from benzophenone ketyl or from sodium naphthalenide, for iron catalyzed ET from...... a Grignard reagent to methyl iodide, and for reduction of methyl iodide with tributyltin hydride or with gaseous hydrogen iodide. Very small KIE's were found for electron transfer to methyl iodide from magnesium in ether or from sodium in ammonia. The reason may be that these reactions are transport...

  20. 21 CFR 582.5634 - Potassium iodide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium iodide. 582.5634 Section 582.5634 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary...

  1. Inclusion complexation of tetrabutylammonium iodide by cyclodextrins

    Indian Academy of Sciences (India)

    Host-guest inclusion complex of an ionic solid (tetrabutyl ammonium iodide) with α- and β- cyclodextrin has been explored by various physicochemical and spectroscopic methods. Surface tension and conductivity studies indicated 1:1 stoichiometry of the inclusion complexes and ¹H NMR and FT-IR studies substantiated ...

  2. 21 CFR 172.375 - Potassium iodide.

    Science.gov (United States)

    2010-04-01

    ... added to a food as a source of the essential mineral iodine, provided the maximum intake of the food as... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium iodide. 172.375 Section 172.375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  3. Electrosorption of tetraalkylammonium ions on silver iodide

    NARCIS (Netherlands)

    Keizer, de A.

    1981-01-01

    The object of the present investigations was to study the ef fect of the adsorption of charged organic ions on electrically charged, solid-liquid interfaces. To that end, symmetrical quater nary ammonium ions were adsorbed on a silver iodide-electrolyte interface at various

  4. Barium iodide and strontium iodide crystals andd scintillators implementing the same

    Science.gov (United States)

    Payne, Stephen A; Cherepy, Nerine J; Hull, Giulia E; Drobshoff, Alexander D; Burger, Arnold

    2013-11-12

    In one embodiment, a material comprises a crystal comprising strontium iodide providing at least 50,000 photons per MeV. A scintillator radiation detector according to another embodiment includes a scintillator optic comprising europium-doped strontium iodide providing at least 50,000 photons per MeV. A scintillator radiation detector in yet another embodiment includes a scintillator optic comprising SrI.sub.2 and BaI.sub.2, wherein a ratio of SrI.sub.2 to BaI.sub.2 is in a range of between 0:1 A method for manufacturing a crystal suitable for use in a scintillator includes mixing strontium iodide-containing crystals with a source of Eu.sup.2+, heating the mixture above a melting point of the strontium iodide-containing crystals, and cooling the heated mixture near the seed crystal for growing a crystal. Additional materials, systems, and methods are presented.

  5. Electrochemical reaction rates in a dye sentisised solar cell - the iodide/tri-iodide redox system

    DEFF Research Database (Denmark)

    Bay, Lasse; West, Keld; Winter-Jensen, Bjørn

    2006-01-01

    The electrochemical reaction rate of the redox couple iodide / tri-iodide in acetonitrile is characterised by impedance spectroscopy. Different electrode materials relevant for the function of dye-sensitised solar cells (DSSC) are investigated. Preferably, the reaction with the iodide / tri......-iodide couple should be fast at the counter electrode, i.e. this electrode must have a high catalytic activity towards the redox couple, and the same reaction must be slow on the photo electrode. The catalytic activity is investigated for platinum, poly(3,4-ethylenedioxythiophene) (PEDOT), polypyrrole (PPy......), and polyaniline (PANI) - all deposited onto fluorine doped tin oxide (FTO) glass. Both Pt and PEDOT are found to have sufficiently high catalytic activities for practical use as counter electrode in DSSC. The reaction resistance on FTO and anatase confirmed the beneficial effect of a compact anatase layer on top...

  6. Iodide handling disorders (NIS, TPO, TG, IYD).

    Science.gov (United States)

    Targovnik, Héctor M; Citterio, Cintia E; Rivolta, Carina M

    2017-03-01

    Iodide Handling Disorders lead to defects of the biosynthesis of thyroid hormones (thyroid dyshormonogenesis, TD) and thereafter congenital hypothyroidism (CH), the most common endocrine disease characterized by low levels of circulating thyroid hormones. The prevalence of CH is 1 in 2000-3000 live births. Prevention of CH is based on prenatal diagnosis, carrier identification, and genetic counseling. In neonates a complete diagnosis of TD should include clinical examination, biochemical thyroid tests, thyroid ultrasound, radioiodine or technetium scintigraphy and perchlorate discharge test (PDT). Biosynthesis of thyroid hormones requires the presence of iodide, thyroid peroxidase (TPO), a supply of hydrogen peroxide (DUOX system), an iodine acceptor protein, thyroglobulin (TG), and the rescue and recycling of iodide by the action of iodotyrosine deiodinase or iodotyrosine dehalogenase 1 (IYD or DEHAL1). The iodide transport is a two-step process involving transporters located either in the basolateral or apical membranes, sodium iodide symporter (NIS) and pendrin (PDS), respectively. TD has been linked to mutations in the solute carrier family 5, member 5 transporter (SLC5A5, encoding NIS), solute carrier family 26, member 4 transporter (SLC26A4, encoding PDS), TPO, DUOX2, DUOXA2, TG and IYD genes. These mutations produce a heterogeneous spectrum of CH, with an autosomal recessive inheritance. Thereafter, the patients are usually homozygous or compound heterozygous for the gene mutations and the parents, carriers of one mutation. In the last two decades, considerable progress has been made in identifying the genetic and molecular causes of TD. Recent advances in DNA sequencing technology allow the massive screening and facilitate the studies of phenotype variability. In this article we included the most recent data related to disorders caused by mutations in NIS, TPO, TG and IYD. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Autofluorescence-free Live-cell Imaging Using Terbium Nanoparticles.

    Science.gov (United States)

    Cardoso Dos Santos, Marcelina; Goetz, Joan; Bartenlian, Hortense; Wong, Ka-Leung; Charbonniere, Loïc Joanny; Hildebrandt, Niko

    2018-02-20

    Fluorescent nanoparticles (NPs) have become irreplaceable tools for advanced cellular and sub-cellular imaging. While very bright NPs require excitation with UV or visible light, which can create strong autofluorescence of biological components, NIR-excitable NPs without autofluorescence issues exhibit much lower brightness. Here, we show the application of a new type of surface-photosensitized terbium NPs (Tb-NPs) for autofluorescence-free intracellular imaging in live HeLa cells. Combination of exceptionally high brightness, high photostability, and long photoluminecence (PL) lifetimes for highly efficient suppression of the short-lived autofluorescence, allowed for time-gated PL imaging of intracellular vesicles over 72 h without toxicity and at extremely low Tb-NP concentrations down to 12 pM. Detection of highly resolved long-lifetime (ms) PL decay curves from small (~10 µm2) areas within single cells within a few seconds emphasized the unprecedented photophysical properties of Tb-NPs for live-cell imaging that extend well beyond currently available nanometric imaging agents.

  8. Solar Thermochemical Hydrogen Production via Terbium Oxide Based Redox Reactions

    Directory of Open Access Journals (Sweden)

    Rahul Bhosale

    2016-01-01

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

  9. Folate Receptor Targeted Alpha-Therapy Using Terbium-149

    CERN Document Server

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

    2014-01-01

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

  10. Hardness and dielectric characteristics of flux grown terbium aluminate crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, K.K.; Kotru, P.N. [Jammu Univ. (India). Dept. of Physics; Tandon, R.P. [National Physical Laboratory, New Delhi (India); Wanklyn, B.M. [Clarendon Laboratory, University of Oxford, Oxford (United Kingdom)

    1999-01-29

    Results of indentation induced Vickers hardness testing and dielectric studies conducted on flux-grown terbium aluminate crystals are presented. It is shown that the Vickers hardness value (H{sub v}) is independent of indentation time, but depends on the applied load. Applying the concept of Hays and Kendall, the load independent values are estimated for (110) and (001) planes. Differential behaviour in the crack formation of two different planes (110) and (001) is observed, while (001) plane develops Palmqvist cracks in the whole load range of 10-100 g, (110) plane shows a transition from Palmqvist to median cracks at 70 g. The fracture toughness, brittleness index and yield strength are determined for both the planes. The hardness anisotropy is reported. The dielectric constant, dielectric loss and conductivity are shown to be dependent on temperature and frequency of the applied a.c. field. The dielectric constant versus temperature shows a transition peak at 230 C, which remains independent of the frequency of the applied a.c. field in the range 1 kHz-13 MHz. (orig.) 36 refs.

  11. Thallium bromide iodide crystal acoustic anisotropy examination.

    Science.gov (United States)

    Mantsevich, S N

    2017-03-01

    Thallium bromide iodide crystal also known as KRS-5 is the well known material used in far infrared radiation applications for optical windows and lenses fabrication. The main advantage of this material is the transparency in wide band of wavelengths from 0.53 to 50μm. Despite such advantages as transparency and large acousto-optic figure of merit values, KRS-5 is rarely used in acousto-optics. Nevertheless this material seems to be promising for far infrared acousto-optic applications. The acoustic and acousto-optic properties of KRS-5 needed for the full use in optoelectronics are not well understood to date. In this paper the detailed examination of thallium bromide iodide crystal acoustic properties is presented. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. 2-Hydroxymethyl-1,3-dimethylimidazolium iodide

    Directory of Open Access Journals (Sweden)

    Meryem Chelghoum

    2011-08-01

    Full Text Available The crystal packing of the title compound, C6H11N2O+·I−, can be described as intercalated layers lying parallel to (010, with the iodide ions located between the cations. A weak intramolecular C—H...O hydrogen bond occurs within the cation. In the crystal, intermolecular O—H...I hydrogen bonds result in the formation of a three-dimensional network and reinforce the cohesion of the ionic structure.

  13. Electrosorption of tetraalkylammonium ions on silver iodide

    OpenAIRE

    Keizer, de, R.J.W.

    1981-01-01

    The object of the present investigations was to study the ef fect of the adsorption of charged organic ions on electrically charged, solid-liquid interfaces. To that end, symmetrical quater nary ammonium ions were adsorbed on a silver iodide-electrolyte interface at various surface charges. The electrochemistry of this model interface is well developed in comparison with other solid liquid interfaces and it is very suited for fundamental electrosorption studies. Special a...

  14. Thermoluminescence of cerium and terbium -doped calcium pyrophosphate

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-10-15

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

  15. Solvent polarity and oxygen sensitivity, rather than viscosity, determine lifetimes of biaryl-sensitised terbium luminescence.

    Science.gov (United States)

    Walter, Edward R H; Williams, J A Gareth; Parker, David

    2017-12-14

    In a macrocyclic terbium complex incorporating a biaryl sensitiser, the observed variation of emission lifetime is shown to be determined by the solubility of oxygen in the solvent system and the relative energy of the chromophore excited state, rather than any dependence on solvent viscosity.

  16. Mercuric Iodide Anticoincidence Shield for Gamma-Ray Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We utilize a new detector material, polycrystalline mercuric iodide, for background suppression by active anticoincidence shielding in gamma-ray spectrometers. Two...

  17. Mercuric Iodide Anticoincidence Shield for Gamma-Ray Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to utilize a new detector material, polycrystalline mercuric iodide, for background suppression by active anticoincidence shielding in gamma-ray...

  18. Effect of nitrogen and oxygen on radiolysis of iodide solution

    Energy Technology Data Exchange (ETDEWEB)

    Karasawa, H.; Endo, M. [Hitachi Ltd., Power and Industrial System R+D Divisions, Ibaraki (Japan)

    1996-12-01

    The effect of nitrogen and oxygen on radiolysis of iodide solution was examined. Direct decomposition of nitrogen by {gamma}-radiation produced nitric acid to decrease a water pH. This resulted in the iodine formation in the radiolysis of iodide solution. Hydrogen peroxide was produced by the radiolysis of water containing oxygen. This worked a reducing agent to suppress the formation of iodine in the radiolysis of iodide solution. In the analytical model, fourteen iodine species were considered and reaction scheme consisted in 124 reactions. The analytical model could estimate the oxidation state of iodide ions. (author) 4 figs., 4 refs.

  19. Electronic and optical properties of lead iodide

    DEFF Research Database (Denmark)

    Ahuja, R.; Arwin, H.; Ferreira da Silva, A.

    2002-01-01

    The electronic properties and the optical absorption of lead iodide (PbI2) have been investigated experimentally by means of optical absorption and spectroscopic ellipsometry, and theoretically by a full-potential linear muffin-tin-orbital method. PbI2 has been recognized as a very promising...... detector material with a large technological applicability. Its band-gap energy as a function of temperature has also been measured by optical absorption. The temperature dependence has been fitted by two different relations, and a discussion of these fittings is given. ©2002 American Institute of Physics....

  20. Potassium Iodide ("KI"): Instructions to Make Potassium Iodide Solution for Use During a Nuclear Emergency (Liquid Form)

    Science.gov (United States)

    ... Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products ... it Email Print Instructions to Make Potassium Iodide Solution for Use During a Nuclear ...

  1. Phase 2 Methyl Iodide Deep-Bed Adsorption Tests

    Energy Technology Data Exchange (ETDEWEB)

    Soelberg, Nick [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    Nuclear fission produces fission products (FPs) and activation products, including iodine-129, which could evolve into used fuel reprocessing facility off-gas systems, and could require off-gas control to limit air emissions to levels within acceptable emission limits. Research, demonstrations, and some reprocessing plant experience have indicated that diatomic iodine can be captured with efficiencies high enough to meet regulatory requirements. Research on the capture of organic iodides has also been performed, but to a lesser extent. Several questions remain open regarding the capture of iodine bound in organic compounds. Deep-bed methyl iodide adsorption testing has progressed according to a multi-laboratory methyl iodide adsorption test plan. This report summarizes the second phase of methyl iodide adsorption work performed according to this test plan using the deep-bed iodine adsorption test system at the Idaho National Laboratory (INL), performed during the second half of Fiscal Year (FY) 2014. Test results continue to show that methyl iodide adsorption using AgZ can achieve total iodine decontamination factors (DFs, ratios of uncontrolled and controlled total iodine levels) above 1,000, until breakthrough occurred. However, mass transfer zone depths are deeper for methyl iodide adsorption compared to diatomic iodine (I2) adsorption. Methyl iodide DFs for the Ag Aerogel test adsorption efficiencies were less than 1,000, and the methyl iodide mass transfer zone depth exceeded 8 inches. Additional deep-bed testing and analyses are recommended to (a) expand the data base for methyl iodide adsorption under various conditions specified in the methyl iodide test plan, and (b) provide more data for evaluating organic iodide reactions and reaction byproducts for different potential adsorption conditions.

  2. Evaluating iodide recycling inhibition as a novel molecular initiating event for thyroid axis disruption

    Science.gov (United States)

    The enzyme iodotyrosine deiodinase (dehalogenase, IYD) catalyzes iodide recycling and promotes iodide retention in thyroid follicular cells. Loss of function or chemical inhibition of IYD reduces available iodide for thyroid hormone synthesis, which leads to hormone insufficiency...

  3. 21 CFR 520.763 - Dithiazanine iodide oral dosage forms.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dithiazanine iodide oral dosage forms. 520.763... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.763 Dithiazanine iodide oral dosage forms. ...

  4. 21 CFR 520.763b - Dithiazanine iodide powder.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dithiazanine iodide powder. 520.763b Section 520.763b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... of use. (1) Dithiazanine iodide powder is administered to dogs by mixing the proper dosage in the dog...

  5. Coulomb explosion of methyl iodide clusters using giga watt laser ...

    Indian Academy of Sciences (India)

    Administrator

    (9⋅54 eV). This higher ionization potential of water decreases the multiphoton ionization probability of the water molecules/clusters as compared to that of methyl iodide molecules/clusters under identical laser excitation conditions. Further, the water has much lower vapour pressure as compared to that of methyl iodide.

  6. Photoluminescence Enhancement in Formamidinium Lead Iodide Thin Films

    NARCIS (Netherlands)

    Fang, Hong-Hua; Wang, Feng; Adjokatse, Sampson; Zhao, Ni; Loi, Maria Antonietta

    2016-01-01

    Formamidinium lead iodide (FAPbI(3)) has a broader absorption spectrum and better thermal stability than the most famous methylammonium lead iodide, thus exhibiting great potential for photovoltaic applications. In this report, the light-induced photoluminescence (PL) evolution in FAPbI(3) thin

  7. Arginine-responsive terbium luminescent hybrid sensors triggered by two crown ether carboxylic acids

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Lasheng [Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Tang, Ke; Ding, Xiaoping [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Wang, Qianming, E-mail: qmwang@scnu.edu.cn [Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Zhou, Zhan; Xiao, Rui [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China)

    2013-12-01

    Crown ether carboxylic acids constitute main building blocks for the synthesis of terbium containing covalent cross-linked luminescent materials. Both the complexes and the hybrid nanomaterials could exhibit remarkable green emissions in pure water. More importantly, they were found to have a profound effect on the luminescence responses to arginine compared with glutamic acid, histidine, tryptophan, threonine, tyrosine and phenylalanine in aqueous environment. The present study provided the possibility of using a host–guest mechanism as a way of signal transduction based on lanthanide supramolecular hybrid materials. - Highlights: • Crown ether carboxylic acids were found to sensitize terbium ions among a group of ethers. • The complexes and silica hybrid materials were both prepared and characterized. • They could exhibit remarkable green emissions in pure water.

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

    Science.gov (United States)

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

    2014-07-07

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

  9. Ferroelastic Fingerprints in Methylammonium Lead Iodide Perovskite

    KAUST Repository

    Hermes, Ilka M.

    2016-02-12

    Methylammonium lead iodide (MAPbI3) perovskite materials show an outstanding performance in photovoltaic devices. However, certain material properties, especially the possible ferroic behavior, remain unclear. We observed distinct nanoscale periodic domains in the piezoresponse of MAPbI3(Cl) grains. The structure and the orientation of these striped domains indicate ferroelasticity as their origin. By correlating vertical and lateral piezoresponse force microscopy experiments performed at different sample orientations with x-ray diffraction, the preferred domain orientation was suggested to be the a1-a2-phase. The observation of these ferroelastic fingerprints appears to strongly depend on the film texture and thus the preparation route. The formation of the ferroelastic twin domains could be induced by internal strain during the cubic-tetragonal phase transition.

  10. Spectrofluorimetric Determination of Human Serum Albumin Using Terbium-Danofloxacin Probe

    OpenAIRE

    Ramezani, Amir M.; Manzoori, Jamshid L.; Amjadi, Mohammad; Jouyban, Abolghasem

    2012-01-01

    A spectrofluorimetric method is proposed for the determination of human serum albumin (HSA) and bovine serum albumin (BSA) using terbium-danofloxacin (Tb3+-Dano) as a fluorescent probe. These proteins remarkably enhance the fluorescence intensity of the Tb3+-Dano complex at 545 nm, and the enhanced fluorescence intensity of Tb3+-Dano is proportional to the concentration of proteins (HSA and BSA). Optimum conditions for the determination of HSA were investigated and found that the maximum resp...

  11. Flavonoid rutin increases thyroid iodide uptake in rats.

    Directory of Open Access Journals (Sweden)

    Carlos Frederico Lima Gonçalves

    Full Text Available Thyroid iodide uptake through the sodium-iodide symporter (NIS is not only an essential step for thyroid hormones biosynthesis, but also fundamental for the diagnosis and treatment of different thyroid diseases. However, part of patients with thyroid cancer is refractory to radioiodine therapy, due to reduced ability to uptake iodide, which greatly reduces the chances of survival. Therefore, compounds able to increase thyroid iodide uptake are of great interest. It has been shown that some flavonoids are able to increase iodide uptake and NIS expression in vitro, however, data in vivo are lacking. Flavonoids are polyhydroxyphenolic compounds, found in vegetables present in human diet, and have been shown not only to modulate NIS, but also thyroperoxidase (TPO, the key enzyme in thyroid hormones biosynthesis, besides having antiproliferative effect in thyroid cancer cell lines. Therefore, we aimed to evaluate the effect of some flavonoids on thyroid iodide uptake in Wistar rats in vivo. Among the flavonoids tested, rutin was the only one able to increase thyroid iodide uptake, so we decided to evaluate the effect of this flavonoid on some aspects of thyroid hormones synthesis and metabolism. Rutin led to a slight reduction of serum T4 and T3 without changes in serum thyrotropin (TSH, and significantly increased hypothalamic, pituitary and brown adipose tissue type 2 deiodinase and decreased liver type 1 deiodinase activities. Moreover, rutin treatment increased thyroid iodide uptake probably due to the increment of NIS expression, which might be secondary to increased response to TSH, since TSH receptor expression was increased. Thus, rutin might be useful as an adjuvant in radioiodine therapy, since this flavonoid increased thyroid iodide uptake without greatly affecting thyroid function.

  12. Flavonoid rutin increases thyroid iodide uptake in rats.

    Science.gov (United States)

    Gonçalves, Carlos Frederico Lima; Lima Gonçalves, Carlos Frederico; Santos, Maria Carolina de Souza dos; de Souza dos Santos, Maria Carolina; Ginabreda, Maria Gloria; Fortunato, Rodrigo Soares; Soares Fortunato, Rodrigo; Carvalho, Denise Pires de; Pires de Carvalho, Denise; Freitas Ferreira, Andrea Claudia

    2013-01-01

    Thyroid iodide uptake through the sodium-iodide symporter (NIS) is not only an essential step for thyroid hormones biosynthesis, but also fundamental for the diagnosis and treatment of different thyroid diseases. However, part of patients with thyroid cancer is refractory to radioiodine therapy, due to reduced ability to uptake iodide, which greatly reduces the chances of survival. Therefore, compounds able to increase thyroid iodide uptake are of great interest. It has been shown that some flavonoids are able to increase iodide uptake and NIS expression in vitro, however, data in vivo are lacking. Flavonoids are polyhydroxyphenolic compounds, found in vegetables present in human diet, and have been shown not only to modulate NIS, but also thyroperoxidase (TPO), the key enzyme in thyroid hormones biosynthesis, besides having antiproliferative effect in thyroid cancer cell lines. Therefore, we aimed to evaluate the effect of some flavonoids on thyroid iodide uptake in Wistar rats in vivo. Among the flavonoids tested, rutin was the only one able to increase thyroid iodide uptake, so we decided to evaluate the effect of this flavonoid on some aspects of thyroid hormones synthesis and metabolism. Rutin led to a slight reduction of serum T4 and T3 without changes in serum thyrotropin (TSH), and significantly increased hypothalamic, pituitary and brown adipose tissue type 2 deiodinase and decreased liver type 1 deiodinase activities. Moreover, rutin treatment increased thyroid iodide uptake probably due to the increment of NIS expression, which might be secondary to increased response to TSH, since TSH receptor expression was increased. Thus, rutin might be useful as an adjuvant in radioiodine therapy, since this flavonoid increased thyroid iodide uptake without greatly affecting thyroid function.

  13. Genetically Encoded FRET-Sensor Based on Terbium Chelate and Red Fluorescent Protein for Detection of Caspase-3 Activity

    Directory of Open Access Journals (Sweden)

    Alexander S. Goryashchenko

    2015-07-01

    Full Text Available This article describes the genetically encoded caspase-3 FRET-sensor based on the terbium-binding peptide, cleavable linker with caspase-3 recognition site, and red fluorescent protein TagRFP. The engineered construction performs two induction-resonance energy transfer processes: from tryptophan of the terbium-binding peptide to Tb3+ and from sensitized Tb3+ to acceptor—the chromophore of TagRFP. Long-lived terbium-sensitized emission (microseconds, pulse excitation source, and time-resolved detection were utilized to eliminate directly excited TagRFP fluorescence and background cellular autofluorescence, which lasts a fraction of nanosecond, and thus to improve sensitivity of analyses. Furthermore the technique facilitates selective detection of fluorescence, induced by uncleaved acceptor emission. For the first time it was shown that fluorescence resonance energy transfer between sensitized terbium and TagRFP in the engineered construction can be studied via detection of microsecond TagRFP fluorescence intensities. The lifetime and distance distribution between donor and acceptor were calculated using molecular dynamics simulation. Using this data, quantum yield of terbium ions with binding peptide was estimated.

  14. Expression of the human sodium/iodide symporter (hNIS) in xenotransplanted human thyroid carcinoma

    NARCIS (Netherlands)

    Smit, J.W.A.; Schröder - van der Elst, J.P.; Karperien, M.; Que, I.; Romijn, J.A.; Heide, van der D.

    2001-01-01

    The uptake of iodide in thyroid epithelial cells is mediated by the sodium/iodide symporter (NIS). The uptake of iodide is of vital importance for thyroid physiology and is a prerequisite for radioiodine therapy in thyroid cancer. Loss of iodide uptake due to diminished expression of the human NIS

  15. Reaction of N-sulfonyltellurimides with methyl iodide

    Energy Technology Data Exchange (ETDEWEB)

    Naddaka, V.I.; Avanesyan, K.V.; Cherkinskaya, M.L.; Minkin, V.I.

    1987-09-20

    While developing researches into the reactivity of tellurimides, the authors studied the previously unknown reaction of N-sulonyltellurimides with methyl iodide. The authors established that bis(diphenyltellurium) oxide and N-methyl-p-toluenesulfonamide are formed when the tellurimide is boiled in methyl iodide. Such a direction is evidently due to the fact that the telluronium salt produced during the reaction is readily hydrolyzed at the Te-N bond on account of the presence of traces of moisture in the methyl iodide. However, the heating of the tellurimides with an excess of anhydrous methyl iodide in a sealed tube leads to diaryltellurium diiodides and N,N-dimethylsulfonamides. The PMR spectra of solutions of the substances in deuterochloroform were recorded on a Tesla-BS-487 spectrometer at 80 MHz with HMDS as internal standard. The IR spectra were obtained on a Specord 71-IR instrument in Vaseline oil.

  16. Radiative efficiency of lead iodide based perovskite solar cells

    National Research Council Canada - National Science Library

    Tvingstedt, Kristofer; Malinkiewicz, Olga; Baumann, Andreas; Deibel, Carsten; Snaith, Henry J; Dyakonov, Vladimir; Bolink, Henk J

    2014-01-01

    .... We herein determine the important figure of merit of radiative efficiency for Methylammonium Lead Iodide perovskite solar cells and, to put in context, relate it to an organic photovoltaic (OPV) model device...

  17. Improved Stability of Mercuric Iodide Detectors for Anticoincidence Shields Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to utilize guard ring electrode structures and a new film growth technique to create improved polycrystalline mercuric iodide detectors for background...

  18. Fluoride, bromide and iodide in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza, F.P.

    fairly constant ratio to chlorinity. Concentrations of iodide were small (0.01-0.024 mg/l) with higher concentration occurring at the surface and bottom layers. Results suggested the semi-conservative, conservative and non-conservative characters...

  19. Accelerated degradation of methyl iodide by agrochemicals.

    Science.gov (United States)

    Zheng, Wei; Papiernik, Sharon K; Guo, Mingxin; Yates, Scott R

    2003-01-29

    The fumigant methyl iodide (MeI, iodomethane) is considered a promising alternative to methyl bromide (MeBr) for soil-borne pest control in high-cash-value crops. However, the high vapor pressure of MeI results in emissions of a significant proportion of the applied mass into the ambient air, and this may lead to pollution of the environment. Integrating the application of certain agrochemicals with soil fumigation provides a novel approach to reduce excessive fumigant emissions. This study investigated the potential for several agrochemicals that are commonly used in farming operations, including fertilizers and nitrification inhibitors, to transform MeI in aqueous solution. The pseudo-first-order hydrolysis half-life (t(1/2)) of MeI was approximately 108 d, while the transformation of MeI in aqueous solutions containing selected agrochemicals was more rapid, with t(1/2) nitrification inhibitors). The influence of these agrochemicals on the rate of MeI degradation in soil was also determined. Adsorption to soil apparently reduced the availability of some nitrification inhibitors in the soil aqueous phase and lowered the degradation rate in soil. In contrast, addition of the nitrification inhibitors thiourea and allylthiourea to soil significantly accelerated the degradation of MeI, possibly due to soil surface catalysis. The t(1/2) of MeI was 300 h).

  20. Chloride, bromide and iodide scintillators with europium

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2016-09-27

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

  1. Prevention of organic iodide formation in BWR`s

    Energy Technology Data Exchange (ETDEWEB)

    Karjunen, T. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland); Laitinen, T.; Piippo, J.; Sirkiae, P. [VTT Manufacturing Technology (Finland)

    1996-12-01

    During an accident, many different forms of iodine may emerge. Organic iodides, such as methyl iodide and ethyl iodide, are relatively volatile, and thus their appearance leads to increased concentration of gaseous iodine. Since organic iodides are also relatively immune to most accident mitigation measures, such as sprays and filters, they can affect the accident source term significantly even when only a small portion of iodine is in organic form. Formation of organic iodides may not be limited by the amount of organic substances available. Excessive amounts of methane can be produced, for example, during oxidation of boron carbide, which is used in BWR`s as a neutron absorber material. Another important source is cable insulation. In a BWR, a large quantity of cables is placed below the pressure vessel. Thus a large quantity of pyrolyse gases will be produced, should the vessel fail. Organic iodides can be formed as a result of many different reactions, but at least in certain conditions the main reaction takes place between an organic radical produced by radiolysis and elemental iodine. A necessary requirement for prevention of organic iodide production is therefore that the pH in the containment water pools is kept high enough to eliminate formation of elemental iodine. In a typical BWR the suppression pool water is usually unbuffered. As a result, the pH may be dominated by chemicals introduced during an accident. If no system for adding basic chemicals is operable, the main factor affecting pool water pH may be hydrochloric acid released during cable degradation. Should this occur, the conditions could be very favorable for production of elemental iodine and, consequently, formation of organic iodides. Although high pH is necessary for iodine retention, it could have also adverse effects. High pH may, for example, accelerate corrosion of containment materials and alter the characteristics of the solid corrosion products. (author) 6 figs., 1 tab., 13 refs.

  2. Electrochemical reaction rates in a dye-sensitised solar cell - the iodide/tri-iodide redox system

    DEFF Research Database (Denmark)

    Bay, L.; West, K.; Winther-Jensen, B.

    2006-01-01

    The electrochemical reaction rate of the redox couple iodide/tri-iodide in acetonitrile is characterised by impedance spectroscopy. Different electrode materials relevant for the function of dye-sensitised solar cells (DSSC) are investigated. Preferably, the reaction with the iodide....../tri-iodide couple should be fast at the counter electrode, i.e. this electrode must have a high catalytic activity towards the redox couple, and the same reaction must be slow on the photo electrode. The catalytic activity is investigated for platinum, poly(3,4-ethylenedioxythiophene) (PEDOT), polypyrrole (PPy......), and polyaniline (PANI)-all deposited onto fluorine-doped tin oxide (FTO) glass. Both Pt and PEDOT are found to have sufficiently high catalytic activities for practical use as counter electrodes in DSSC. The reaction resistance on FTO and anatase confirmed the beneficial effect of a compact anatase layer on top...

  3. Molecular imaging using sodium iodide symporter (NIS)

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Je Yoel [School of Dentistry, Kyungpook National Univ., Daegu (Korea, Republic of)

    2004-04-01

    Radioiodide uptake in thyroid follicular epithelial cells, mediated by a plasma membrane transporter, sodium iodide symporter (NIS), provides a first step mechanism for thyroid cancer detection by radioiodide injection and effective radioiodide treatment for patients with invasive, recurrent, and/or metastatic thyroid cancers after total thyroidectomy. NIS gene transfer to tumor cells may significantly and specifically enhance internal radioactive accumulation of tumors following radioiodide administration, and result in better tumor control. NIS gene transfers have been successfully performed in a variety of tumor animal models by either plasmid-mediated transfection or virus (adenovirus or retrovirus)-mediated gene delivery. These animal models include nude mice xenografted with human melanoma, glioma, breast cancer of prostate cancer, rats with subcutaneous thyroid tumor implantation, as well as the rat intracranial glioma model. In these animal models, non-invasive imaging of in vivo tumors by gamma camera scintigraphy after radioiodide or technetium injection has been performed successfully, suggesting that the NIS can serve as an imaging reporter gene for gene therapy trials. In addition, the tumor killing effects of I-131, ReO4-188 and At-211 after NIS gene transfer have been demonstrated in in vitro clonogenic assays and in vivo radioiodide therapy studies, suggesting that NIS gene can also serve as a therapeutic requires a more efficient and specific system of gene delivery with better retention of radioiodide in tumor. Results thus far are, however, promising, and suggest that NIS gene transfer followed by radioiodide treatment will allow non-invasive in vivo imaging to assess the outcome of gene therapy and provide a therapeutic strategy for a variety of human diseases.

  4. Formamidinium iodide: crystal structure and phase transitions

    Directory of Open Access Journals (Sweden)

    Andrey A. Petrov

    2017-04-01

    Full Text Available At a temperature of 100 K, CH5N2+·I− (I, crystallizes in the monoclinic space group P21/c. The formamidinium cation adopts a planar symmetrical structure [the r.m.s. deviation is 0.002 Å, and the C—N bond lengths are 1.301 (7 and 1.309 (8 Å]. The iodide anion does not lie within the cation plane, but deviates from it by 0.643 (10 Å. The cation and anion of I form a tight ionic pair by a strong N—H...I hydrogen bond. In the crystal of I, the tight ionic pairs form hydrogen-bonded zigzag-like chains propagating toward [20-1] via strong N—H...I hydrogen bonds. The hydrogen-bonded chains are further packed in stacks along [100]. The thermal behaviour of I was studied by different physicochemical methods (thermogravimetry, differential scanning calorimetry and powder diffraction. Differential scanning calorimetry revealed three narrow endothermic peaks at 346, 387 and 525 K, and one broad endothermic peak at ∼605 K. The first and second peaks are related to solid–solid phase transitions, while the third and fourth peaks are attributed to the melting and decomposition of I. The enthalpies of the phase transitions at 346 and 387 K are estimated as 2.60 and 2.75 kJ mol−1, respectively. The X-ray powder diffraction data collected at different temperatures indicate the existence of I as the monoclinic (100–346 K, orthorhombic (346–387 K and cubic (387–525 K polymorphic modifications.

  5. Iodide kinetics and experimental I-131 therapy in a xenotransplanted human sodium-iodide symporter-transfected human follicular thyroid carcinoma cell line

    NARCIS (Netherlands)

    Smit, J.W.A.; Elst, van der J.P.; Karperien, M.; Que, I.; Stokkel, M.; Heide, van der D.; Romijn, J.A.

    2002-01-01

    Uptake of iodide is a prerequisite for radioiodide therapy in thyroid cancer. However, loss of iodide uptake is frequently observed in metastasized thyroid cancer, which may be explained by diminished expression of the human sodium-iodide symporter (hNIS). We studied whether transfection of hNIS

  6. Iodide kinetics and experimental (131)I therapy in a xenotransplanted human sodium-iodide symporter-transfected human follicular thyroid carcinoma cell line

    NARCIS (Netherlands)

    Smit, Jan W. A.; Schröder-van der Elst, Janny P.; Karperien, Marcel; Que, Ivo; Stokkel, Marcel; van der Heide, Daan; Romijn, Johannes A.

    2002-01-01

    Uptake of iodide is a prerequisite for radioiodide therapy in thyroid cancer. However, loss of iodide uptake is frequently observed in metastasized thyroid cancer, which may be explained by diminished expression of the human sodium-iodide symporter (hNIS). We studied whether transfection of hNIS

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-11-01

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

  8. Graphene quantum dots-terbium ions as novel sensitive and selective time-resolved luminescent probes.

    Science.gov (United States)

    Llorent-Martínez, Eulogio J; Durán, Gema M; Ríos, Ángel; Ruiz-Medina, Antonio

    2018-01-01

    We propose an alternative approach for the development of analytical methods based on terbium-sensitized luminescence (TSL). TSL is based on the complexation between Tb(III) ions and fluorescent organic compounds that have appropriate functional groups to complex with Tb(III). We report the use of graphene quantum dot (GQDs) nanoparticles to improve the sensitivity and selectivity of TSL detection. GQDs can react with terbium ions through the carboxylic groups present in their structure. These Tb(III)-GQD complexes, formed in situ in aqueous solution, can be used as time-resolved luminescent probes. Ascorbic acid was selected as a target analyte to demonstrate the suitability of the proposed method. The selectivity of the TSL method was highly improved for most of the interferences tested. Under the optimum conditions [Tb(III) concentration 5 × 10-4 mol L-1, GQD concentration 4 mg L-1], a minimum 100% increase in selectivity was observed for several vitamins and common cations that may be present in the samples to be analyzed. In addition, the analytical signal showed a 30% enhancement with the use of GQDs compared with the use of merely Tb(III) ions, with a detection limit of 0.12 μg mL-1. The repeatability and intermediate precision were lower than 3% and 5%, respectively. From the results obtained, the implementation of GQDs in TSL can lead to the development of novel time-resolved luminescent probes with high analytical potential. Graphical abstract Quenching of Tb(III)-graphene quantum dot (GQD) luminescence by ascorbic acid (AA). TBL terbium-sensitized luminescence.

  9. Fluorescence study of some terbium-oligopeptide complexes in methanolic solution.

    Science.gov (United States)

    Rabouan, S; Delage, J; Durand, W; Prognon, P; Barthes, D

    2000-04-03

    This study concerned the use of lanthanide chelates to detect glycyl-leucyl-phenylalanine (GLF) and its homologues. Spectroscopic analysis of peptides without or with terbium complexation revealed the formation of (LF)(3)(Tb)(2), (GF)(3)(Tb)(2), (GLF)(3)(Tb)(2) and (FL)(4)Tb, (FG)(4)Tb complexes with high stability constants in methanolic solutions (pK(d)>13). Lanthanide chelate emission displayed a large Stokes shift (>270 nm), which allowed Tb chelates of GLF and its derivatives to be used for detection purposes. However, this preliminary study indicated some important limitations associated with lanthanide chelation, such as high methanolic content.

  10. Electromagnetic properties of terbium gallium garnet at millikelvin temperatures and low photon energy

    Science.gov (United States)

    Kostylev, Nikita; Goryachev, Maxim; Bushev, Pavel; Tobar, Michael E.

    2017-07-01

    Electromagnetic properties of single crystal terbium gallium garnet are characterised from room down to millikelvin temperatures using the whispering gallery mode method. Microwave spectroscopy is performed at low powers equivalent to a few photons in energy and conducted as functions of the magnetic field and temperature. A phase transition is detected close to the temperature of 3.5 K. This is observed for multiple whispering gallery modes causing an abrupt negative frequency shift and a change in transmission due to extra losses in the new phase caused by a change in complex magnetic susceptibility.

  11. Nuclear excitation functions from 40 to 200 MeV proton irradiation of terbium

    Energy Technology Data Exchange (ETDEWEB)

    Engle, Jonathan W., E-mail: jwengle@lanl.gov; Mashnik, Stepan G.; Parker, Lauren A.; Jackman, Kevin R.; Bitteker, Leo J.; Ullmann, John L.; Gulley, Mark S.; Pillai, Chandra; John, Kevin D.; Birnbaum, Eva R.; Nortier, Francois M.

    2016-01-01

    Nuclear formation cross sections are reported for 26 radionuclides, measured with 40–200 MeV proton irradiations of terbium foils. These data provide the basis for the production of medically relevant radionuclides (e.g., {sup 152}Tb, {sup 155}Tb, {sup 155}Eu, and {sup 156}Eu) and {sup 153}Gd, a potential source used in ongoing efforts to characterize stellar nucleosynthesis routes. Computational predictions from the ALICE2011, CEM03.03, Bertini, and INCL + ABLA codes are compared with newly measured data to contribute to the ongoing process of code development, and yields are calculated for selected radionuclides using measured data.

  12. A Simple and Safe Spectrophotometric Method for Iodide Determination

    Directory of Open Access Journals (Sweden)

    Hermin Sulistyarti

    2015-06-01

    Full Text Available In order to practice green chemistry, a simple and safe spectrophotometric method for iodide determination has been successfully developed based on the formation of a blue starch-iodine complex. Iodide was oxidized to form iodine prior to the addition of a starch solution, and the blue starch-iodine complex was directly detected spectrophoto-metrically at a wavelength of 615 nm. The chemical parameters, such as type, reaction time, as well as concentration of oxidizing agents and solution pH were optimized with respect to sensitivity and analysis time. The method showed optimum results under iodate oxidant with a mol ratio of IO3-:I- =1:3, reaction time of 5 minutes, and solution pH of 5. Under these optimum conditions, the method showed linierity measurements from 5-40 mg/L iodide with a correlation (R2 of 0.9889. This technique offers a simple, safe, accurate, and relatively fast method for iodide determination, which is prospective for monitoring iodide samples.

  13. Micelle-enhanced and terbium-sensitized spectrofluorimetric determination of gatifloxacin and its interaction mechanism

    Science.gov (United States)

    Guo, Changchuan; Wang, Lei; Hou, Zhun; Jiang, Wei; Sang, Lihong

    2009-05-01

    A terbium-sensitized spectrofluorimetric method using an anionic surfactant, sodium dodecyl benzene sulfonate (SDBS), was developed for the determination of gatifloxacin (GFLX). A coordination complex system of GFLX-Tb 3+-SDBS was studied. It was found that SDBS significantly enhanced the fluorescence intensity of the complex (about 11-fold). Optimal experimental conditions were determined as follows: excitation and emission wavelengths of 331 and 547 nm, pH 7.0, 2.0 × 10 -4 mol l -1 terbium (III), and 2.0 × 10 -4 mol l -1 SDBS. The enhanced fluorescence intensity of the system (Δ If) showed a good linear relationship with the concentration of GFLX over the range of 5.0 × 10 -10 to 5.0 × 10 -8 mol l -1 with a correlation coefficient of 0.9996. The detection limit (3 σ) was determined as 6.0 × 10 -11 mol l -1. This method has been successfully applied to the determination of GFLX in pharmaceuticals and human urine/serum samples. Compared with most of other methods reported, the rapid and simple procedure proposed in the text offers higher sensitivity, wider linear range, and better stability. The interaction mechanism of the system is also studied by the research of ultraviolet absorption spectra, surface tension, solution polarity and fluorescence polarization.

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

    Science.gov (United States)

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

    2009-01-01

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

  15. Phase 1 Methyl Iodide Deep-Bed Adsorption Tests

    Energy Technology Data Exchange (ETDEWEB)

    Soelberg, Nick [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-08-22

    Nuclear fission results in the production of fission products (FPs) and activation products including iodine-129, which could evolve into used fuel reprocessing facility off-gas systems, and could require off-gas control to limit air emissions to levels within acceptable emission limits. Research, demonstrations, and some reprocessing plant experience have indicated that diatomic iodine can be captured with efficiencies high enough to meet regulatory requirements. Research on the capture of organic iodides has also been performed, but to a lesser extent [Jubin 2012b]. Several questions remain open regarding the capture of iodine bound in organic compounds. Deep-bed methyl iodide adsorption testing has progressed according to a multi-laboratory methyl iodide adsorption test plan. This report summarizes the first phase of methyl iodide adsorption work performed according to this test plan using the deep-bed iodine adsorption test system at the Idaho National Laboratory (INL), performed during Fiscal Year (FY) 2013 and early FY-2014. Testing has been performed to address questions posed in the test plan, and followed the testing outline in the test plan. Tests established detection limits, developed procedures for sample analysis with minimal analytical interferences, and confirmed earlier results that show that the methyl iodide reacts when in contact with the AgZ sorbent, and not significantly in the gas flow upstream of the sorbent. The reaction(s) enable separation of the iodine from the organic moiety, so that the iodine can chemisorb onto the sorbent. The organic moiety can form other compounds, some of which are organic compounds that are detected and can be tentatively identified using GC-FID and GCMS. Test results also show that other gas constituents (NOx and/or H2O) can affect the methyl iodide reactions. With NOx and H2O present in the gas stream, the majority of uncaptured iodine exiting iodine-laden sorbent beds is in the form of I2 or HI, species that

  16. Standard free energy of formation of iron iodide

    Science.gov (United States)

    Khandkar, A.; Tare, V. B.; Wagner, J. B., Jr.

    1983-01-01

    An experiment is reported where silver iodide is used to determine the standard free energy of formation of iron iodide. By using silver iodide as a solid electrolyte, a galvanic cell, Ag/AgI/Fe-FeI2, is formulated. The standard free energy of formation of AgI is known, and hence it is possible to estimate the standard free energy of formation of FeI2 by measuring the open-circuit emf of the above cell as a function of temperature. The free standard energy of formation of FeI2 determined by this method is -38784 + 24.165T cal/mol. It is estimated that the maximum error associated with this method is plus or minus 2500 cal/mol.

  17. Enhanced Olefin Cross Metathesis Reactions: The Copper Iodide Effect

    Science.gov (United States)

    Voigtritter, Karl; Ghorai, Subir

    2011-01-01

    Copper iodide has been shown to be an effective co-catalyst for the olefin cross metathesis reaction. In particular, it has both a catalyst stabilizing effect due to iodide ion, as well as copper(I)-based phosphine-scavenging properties that apply to use of the Grubbs-2 catalyst. A variety of Michael acceptors and olefinic partners can be cross-coupled under mild conditions in refluxing diethyl ether that avoid chlorinated solvents. This effect has also been applied to chemistry in water at room temperature using the new surfactant TPGS-750-M. PMID:21528868

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-03-01

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

  19. Study of potential inhibitors of thyroid iodide uptake by using CHO cells stably expressing the human sodium/iodide symporter (hNIS) protein.

    Science.gov (United States)

    Agretti, P; Dimida, A; De Marco, G; Ferrarini, E; Rodrìguez Gonzàlez, J C; Santini, F; Vitti, P; Pinchera, A; Tonacchera, M

    2011-03-01

    Thyroid gland is highly dependent on dietary intake of iodine for normal function, so it is particularly subjected to "endocrine disruptor" action. The human sodium/iodide symporter (hNIS) is an integral plasma membrane glycoprotein mediating the active transport of iodide into thyroid follicular cells, a crucial step for thyroid hormone biosynthesis. Beyond to perchlorate and thyocianate ions a few other inhibitors of iodide uptake have been described. The aim of this study was to investigate if 10 substances usually used as drugs in clinical practice were able to inhibit NIS-mediated iodide uptake in vitro. A CHO cell line stably expressing hNIS was used to test any inhibition of NIS-mediated iodide uptake exerted by drugs. Perchlorate and thyocianate ions were used as positive controls. None of the analyzed substances was able to significantly inhibit iodide uptake in our system. As we expected, perchlorate and thyocianate ions were able to inhibit iodide uptake in a dose-dependent manner. In conclusion, we carried out an in vitro assay to evaluate the potential inhibitory effect of common drugs on NISmediated iodide uptake by using CHO-hNIS cells. None of the analyzed substances was able to inhibit iodide uptake; only perchlorate and thyocianate were able to inhibit iodide uptake in a dose-dependent manner.

  20. Role of -methyl-8-(alkoxy) quinolinium iodide in suppression of ...

    Indian Academy of Sciences (India)

    There is a great deal of interest in developing small molecule inhibitors of protein misfolding and aggregation due to a growing number of pathologic states known as amyloid disorders. ... -methyl-8-(alkoxy)quinolinium iodide on aggregation behaviour of hen egg white lysozyme (HEWL) at alkaline pH has been studied.

  1. Detection of apoptotic cells using propidium iodide staining

    NARCIS (Netherlands)

    Newbold, Andrea; Martin, Ben P.; Cullinane, Carleen; Bots, Michael

    2014-01-01

    Flow cytometry assays are often used to detect apoptotic cells in in vitro cultures. Depending on the experimental model, these assays can also be useful in evaluating apoptosis in vivo. In this protocol, we describe a propidium iodide (PI) flow cytometry assay to evaluate B-cell lymphomas that have

  2. Silver iodide nanoparticle as an efficient and reusable catalyst for ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 125; Issue 5. Silver iodide nanoparticle as an efficient and reusable catalyst for the one-pot synthesis of benzofurans under aqueous conditions. Javad Safaei-Ghomi Mohammad Ali Ghasemzadeh. Volume 125 Issue 5 September 2013 pp 1003-1008 ...

  3. Confinement Effects in Low-Dimensional Lead Iodide Perovskite Hybrids

    NARCIS (Netherlands)

    Kamminga, Machteld E.; Fang, Honghua; Filip, Marina R.; Giustino, Feliciano; Baas, Jacobus; Blake, Graeme R.; Loi, Maria Antonietta; Palstra, Thomas T. M.

    2016-01-01

    We use a layered solution crystal growth technique to synthesize high-quality single crystals of phenylalkylammonium lead iodide organic/inorganic hybrid compounds. Single-crystal X-ray diffraction reveals low-dimensional structures consisting of inorganic sheets separated by bilayers of the organic

  4. Temperature Dependent Charge Carrier Dynamics in Formamidinium Lead Iodide Perovskite

    NARCIS (Netherlands)

    Gelvez Rueda, M.C.; Renaud, N.; Grozema, F.C.

    2017-01-01

    The fundamental opto-electronic properties of organic-inorganic hybrid perovskites are strongly affected by their structural parameters. These parameters are particularly critical in formamidinium lead iodide (FAPbI3), in which its large structural disorder leads to a non-perovskite

  5. Impact of potassium iodide on thyroidectomy for Graves' disease: Implications for safety and operative difficulty.

    Science.gov (United States)

    Randle, Reese W; Bates, Maria F; Long, Kristin L; Pitt, Susan C; Schneider, David F; Sippel, Rebecca S

    2018-01-01

    Potassium iodide often is prescribed prior to thyroidectomy for Graves' disease, but the effect of potassium iodide on the ease and safety of thyroidectomy for Graves' is largely unknown. We conducted a prospective, cohort study of patients with Graves' disease undergoing thyroidectomy. For the first 8 months, no patients received potassium iodide; for the next 8 months, potassium iodide was added to the preoperative protocol for all patients. Outcomes included operative difficulty (based on the Thyroidectomy Difficulty Scale) and complications. We included a total of 31 patients in the no potassium iodide group and 28 in the potassium iodide group. According to the Thyroidectomy Difficulty Scale, gland vascularity decreased in the potassium iodide group (mean score 2.6 vs 3.3, P = .04), but there were no differences in friability, fibrosis, or size of the thyroid or in overall difficulty of operation (P = not significant for all). Despite similar operative difficulty, patients prescribed potassium iodide were less likely to experience transient hypoparathyroidism (7% vs 26%, P = .018) and transient hoarseness (0% vs 16%, P = .009) compared with the no potassium iodide group. Potassium iodide administration decreases gland vascularity, but does not change the overall difficulty of thyroidectomy. Preoperative use of potassium iodide solution was, however, associated with less transient hypoparathyroidism and transient hoarseness, suggesting that potassium iodide improves the safety of thyroidectomy for Graves' disease. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. FY-2015 Methyl Iodide Deep-Bed Adsorption Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Soelberg, Nicholas Ray [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony Leroy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-30

    Nuclear fission produces fission and activation products, including iodine-129, which could evolve into used fuel reprocessing facility off-gas systems, and could require off-gas control to limit air emissions to levels within acceptable emission limits. Deep-bed methyl iodide adsorption testing has continued in Fiscal Year 2015 according to a multi-laboratory methyl iodide adsorption test plan. Updates to the deep-bed test system have also been performed to enable the inclusion of evaporated HNO3 and increased NO2 concentrations in future tests. This report summarizes the result of those activities. Test results showed that iodine adsorption from gaseous methyl iodide using reduced silver zeolite (AgZ) resulted in initial iodine decontamination factors (DFs, ratios of uncontrolled and controlled total iodine levels) under 1,000 for the conditions of the long-duration test performed this year (45 ppm CH3I, 1,000 ppm each NO and NO2, very low H2O levels [3 ppm] in balance air). The mass transfer zone depth exceeded the cumulative 5-inch depth of 4 bed segments, which is deeper than the 2-4 inch depth estimated for the mass transfer zone for adsorbing I2 using AgZ in prior deep-bed tests. The maximum iodine adsorption capacity for the AgZ under the conditions of this test was 6.2% (6.2 g adsorbed I per 100 g sorbent). The maximum Ag utilization was 51%. Additional deep-bed testing and analyses are recommended to (a) expand the data base for methyl iodide adsorption and (b) provide more data for evaluating organic iodide reactions and reaction byproducts for different potential adsorption conditions.

  7. Thermo-transferred thermoluminescence (TTTl) in potassium-yttrium double fluoride doped with terbium

    Energy Technology Data Exchange (ETDEWEB)

    Gallegos, A.; Rivera, T.; Diaz G, J. A. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Azorin, J. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, San Rafael Atlixco No. 186, Col. Vicentina, 09340 Mexico D. F. (Mexico); Azorin, J. C. [Universidad de Guanajuato, Division de Ciencias e Ingenierias-Campus Leon, Lomas del Bosque No. 103, Col. Lomas del Campestre, 37000 Leon, Guanajuato (Mexico); Licona, R.; Rivas, F.; Hernandez C, G. [Benemerita Universidad Autonoma de Puebla, Facultad de Ciencias Quimicas, 14 Sur y San Claudio, Ciudad Universitaria, Puebla de Zaragoza, Puebla (Mexico); Khaidukov, N. [Institute of General and Inorganic Chemistry, Lenin SK 11 Prospect 31, Moscow 117907 (Russian Federation)

    2011-02-15

    This paper presents results of studying the thermo-transferred thermoluminescence (TTTl) phenomenon in potassium-yttrium double fluoride doped with terbium (K{sub 2}YF{sub 5:}Tb) at different impurity concentrations (0.8%, 0.95% and 0.99%). Previously to study the TTTl phenomenon, structural characterization and chemical composition of the materials were determined. The structural studies were conducted using a scanning electron microscope; meanwhile, chemical composition was analyzed using energy dispersive X-ray spectroscopy. Thermoluminescence kinetics was studied irradiating the samples with {sup 137}Cs gamma rays as well as with {sup 90}Sr/{sup 90}Y beta rays, analyzing the glow curves by the deconvolution method for obtaining the kinetic parameters. (Author)

  8. The influence of pressure on the photoluminescence properties of a terbium-adipate framework

    Science.gov (United States)

    Spencer, Elinor C.; Zhao, Jing; Ross, Nancy L.; Andrews, Michael B.; Surbella, Robert G.; Cahill, Christopher L.

    2013-06-01

    The influence of pressure (over the 0-4.7 GPa range) on the photoluminescence emissions and crystal structure of the known 3D terbium-adipate metal-organic framework material Tb-GWMOF6 has been evaluated by high-pressure single-crystal X-ray diffraction and spectroscopic techniques. The results from this study show that this complex lanthanide framework structure undergoes three phase transitions within the 0-4 GPa pressure range that involve alterations in the number of symmetry independent Tb3+ ion sites within the crystal lattice. These pressure induced modifications to the structure of Tb-GWMOF6 lead to pronounced changes in the profiles of the 5D4→7F5 emission spectra of this complex.

  9. Terbium Radionuclides for Theranostics Applications: A Focus On MEDICIS-PROMED

    Science.gov (United States)

    Cavaier, R. Formento; Haddad, F.; Sounalet, T.; Stora, T.; Zahi, I.

    A new facility, named CERN-MEDICIS, is under construction at CERN to produce radionuclides for medical applications. In parallel, the MEDICIS-PROMED, a Marie Sklodowska-Curie innovative training network of the Horizon 2020 European Commission's program, is being coordinated by CERN to train young scientists on the production and use of innovative radionuclides and develop a network of experts within Europe. One program within MEDICIS-PROMED is to determine the feasibility of producing innovative radioisotopes for theranostics using a commercial middle-sized high-current cyclotron and the mass separation technology developed at CERN-MEDICIS. This will allow the production of high specific activity radioisotopes not achievable with the common post-processing by chemical separation. Radioisotopes of scandium, copper, arsenic and terbium have been identified. Preliminary studies of activation yield and irradiation parameters optimization for the production of Tb-149 will be described.

  10. Dielectric and conducting behavior of gadolinium-terbium fumarate heptahydrate crystals

    Science.gov (United States)

    Shah, M. D.; Want, B.

    2015-07-01

    Gadolinium-terbium fumarate heptahydrate crystals were grown in silica gel by using single gel diffusion technique. The crystals were characterized by different physico-chemical techniques of characterization. Powder X-ray diffraction results showed that the grown material is purely crystalline in nature. Elemental analyses suggested the chemical formula of the compound to be Gd Tb (C4H2O4)3ṡ7H2O. Energy dispersive X-ray analysis confirmed the presence of Gd and Tb in the title compound. The dielectric and conductivity studies of the grown compound were carried as function of frequency of applied field and the temperature. The grown material showed a dielectric anomaly which was correlated with its thermal behavior. The ac conductivity of the material showed Jonscher's power law behavior: σ(ω)=σo+Aωs, with a temperature-dependent power exponent s(<1). The conductivity was found to be a function of temperature and frequency.

  11. Highly sensitive detection of dipicolinic acid with a water-dispersible terbium-metal organic framework.

    Science.gov (United States)

    Bhardwaj, Neha; Bhardwaj, Sanjeev; Mehta, Jyotsana; Kim, Ki-Hyun; Deep, Akash

    2016-12-15

    The sensitive detection of dipicolinic acid (DPA) is strongly associated with the sensing of bacterial organisms in food and many types of environmental samples. To date, the demand for a sensitive detection method for bacterial toxicity has increased remarkably. Herein, we investigated the DPA detection potential of a water-dispersible terbium-metal organic framework (Tb-MOF) based on the fluorescence quenching mechanism. The Tb-MOF showed a highly sensitive ability to detect DPA at a limit of detection of 0.04nM (linear range of detection: 1nM to 5µM) and also offered enhanced selectivity from other commonly associated organic molecules. The present study provides a basis for the application of Tb-MOF for direct, convenient, highly sensitive, and specific detection of DPA in the actual samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. A New Bis(phthalocyaninato) Terbium Single-Ion Magnet with an Overall Excellent Magnetic Performance.

    Science.gov (United States)

    Chen, Yuxiang; Ma, Fang; Chen, Xiaoxiang; Dong, Bowei; Wang, Kang; Jiang, Shangda; Wang, Chiming; Chen, Xin; Qi, Dongdong; Sun, Haoling; Wang, Bingwu; Gao, Song; Jiang, Jianzhuang

    2017-11-20

    Bulky and strong electron-donating dibutylamino groups were incorporated onto the peripheral positions of one of the two phthalocyanine ligands in the bis(phthalocyaninato) terbium complex, resulting in the isolation of heteroleptic double-decker (Pc)Tb{Pc[N(C4H9)2]8} {Pc = phthalocyaninate; Pc[N(C4H9)2]8 = 2,3,9,10,16,17,23,24-octakis(dibutylamino)phthalocyaninate} with the nature of an unsymmetrical molecular structure, a square-antiprismatic coordination geometry, an intensified coordination field strength, and the presence of organic radical-f interaction. As a total result of all these factors, this sandwich-type tetrapyrrole lanthanide single-ion magnet (SIM) exhibits an overall enhanced magnetic performance including a high blocking temperature (TB) of 30 K and large effective spin-reversal energy barrier of Ueff = 939 K, rendering it the best sandwich-type tetrapyrrole lanthanide SIM reported thus far.

  13. Ultralarge magneto-optic rotations and rotary dispersion in terbium gallium garnet single crystal.

    Science.gov (United States)

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

    2015-06-10

    We report systematically acquired data on the Verdet constant of terbium gallium garnet for wavelengths ranging from visible to near-infrared (405-830 nm) regime. Our experimental method of Stokes polarimetry is based on the Fourier decomposition of the received light intensity and allows unambiguous determination of both the Faraday rotation and the ellipticity of the emergent light. Temperature-dependent investigations in the range of 8-300 K extend earlier reports and verify the Verdet's constant direct dependence on the magnetization, whose first-order approximation is simply a manifestation of the Curie's law. Further, a least-squares fitting of the experimental data correlates well with theoretical predictions. At a wavelength of 405 nm and temperature of 8 K, the rotation is approximately 500°.

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

    Energy Technology Data Exchange (ETDEWEB)

    El-Yazbi, Amira F.; Loppnow, Glen R., E-mail: glen.loppnow@ualberta.ca

    2013-07-05

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

  15. Fine- and hyperfine structure investigations of even configuration system of atomic terbium

    Science.gov (United States)

    Stefanska, D.; Elantkowska, M.; Ruczkowski, J.; Furmann, B.

    2017-03-01

    In this work a parametric study of the fine structure (fs) and the hyperfine structure (hfs) for the even-parity configurations of atomic terbium (Tb I) is presented, based in considerable part on the new experimental results. Measurements on 134 spectral lines were performed by laser induced fluorescence (LIF) in a hollow cathode discharge lamp; on this basis, the hyperfine structure constants A and B were determined for 52 even-parity levels belonging to the configurations 4f85d6s2, 4f85d26s or 4f96s6p; in all the cases those levels were involved in the transitions investigated as the lower levels. For 40 levels the hfs was examined for the first time, and for the remaining 12 levels the new measurements supplement our earlier results. As a by-product, also preliminary values of the hfs constants for 84 odd-parity levels were determined (the investigations of the odd-parity levels system in the terbium atom are still in progress). This huge amount of new experimental data, supplemented by our earlier published results, were considered for the fine and hyperfine structure analysis. A multi-configuration fit of 7 configurations was performed, taking into account second-order of perturbation theory, including the effects of closed shell-open shell excitations. Predicted values of the level energies, as well as of magnetic dipole and electric quadrupole hyperfine structure constants A and B, are quoted in cases when no experimental values are available. By combining our experimental data with our own semi-empirical procedure it was possible to identify correctly the lower and upper level of the line 544.1440 nm measured by Childs with the use of the atomic-beam laser-rf double-resonance technique (Childs, J Opt Soc Am B 9;1992:191-6).

  16. Structural and optical characterization of terbium doped ZnGa2O4 thin films deposited by RF magnetron sputtering

    Science.gov (United States)

    Somasundaram, K.; Girija, K. G.; Sudarsan, V.; Selvin, P. Christopher; Vatsa, R. K.

    2016-05-01

    Tb3+ doped ZnGa2O4 nanophosphor (21 nm) has been synthesized via low temperature polyol route and subsequently thin films of the same were deposited on glass and ITO substrates by RF magnetron sputtering. The films were characterized by X-ray Diffraction and luminescence measurements. The XRD pattern showed that Tb3+ doped ZnGa2O4 nanophosphor has a cubic spinel phase. Luminescence behavior of the nanophosphor and as deposited sputtered film was investigated. The PL emission spectra of nanophosphor gave a broad ZnGa2O4 host emission band along with a strong terbium emission and the thin films showed only broad host emission band and there was no terbium ion emission.

  17. Iodide kinetics and experimental (131)I therapy in a xenotransplanted human sodium-iodide symporter-transfected human follicular thyroid carcinoma cell line.

    Science.gov (United States)

    Smit, Jan W A; Schröder-van der Elst, Janny P; Karperien, Marcel; Que, Ivo; Stokkel, Marcel; van der Heide, Daan; Romijn, Johannes A

    2002-03-01

    Uptake of iodide is a prerequisite for radioiodide therapy in thyroid cancer. However, loss of iodide uptake is frequently observed in metastasized thyroid cancer, which may be explained by diminished expression of the human sodium-iodide symporter (hNIS). We studied whether transfection of hNIS into the hNIS-deficient follicular thyroid carcinoma cell line FTC133 restores the in vivo iodide accumulation in xenografted tumors and their susceptibility to radioiodide therapy. In addition, the effects of low-iodide diets and thyroid ablation on iodide kinetics were investigated. Tumors were established in nude mice injected with the hNIS-transfected cell line FTC133-NIS30 and the empty vector transfected cell line FTC133-V4 as a control. Tumors derived from FTC133-NIS30 in mice on a normal diet revealed a high peak iodide accumulation (17.4% of administered activity, measured with an external probe) as compared with FTC133-V4 (4.6%). Half-life in FTC133-NIS30 tumors was 3.8 h. In mice kept on a low-iodide diet, peak activity in FTC133-NIS30 tumors was diminished (8.1%), whereas thyroid iodide accumulation was increased. In thyroid-ablated mice kept on a low-iodide diet, half-life of radioiodide was increased considerably (26.3 h), leading to a much higher area under the time-radioactivity curve than in FTC133-NIS30 tumors in mice on a normal diet without thyroid ablation. Experimental radioiodide therapy with 2 mCi (74 MBq) in thyroid-ablated nude mice, kept on a low-iodide diet, postponed tumor development (4 wk after therapy, one of seven animals revealed tumor vs. five of six animals without therapy). However, 9 wk after therapy, tumors had developed in four of the seven animals. The calculated tumor dose was 32.2 Gy. We conclude that hNIS transfection into a hNIS-defective thyroid carcinoma cell line restores the in vivo iodide accumulation. The unfavorable iodide kinetic characteristics (short half-life) can be partially improved by conventional conditioning with

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

    Science.gov (United States)

    Lotfi, Ali; Manzoori, Jamshid L

    2016-11-01

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

  19. Neutron Diffraction and Electrical Transport Studies on Magnetic Transition in Terbium at High Pressures and Low Temperatures

    Science.gov (United States)

    Thomas, Sarah; Montgomery, Jeffrey; Tsoi, Georgiy; Vohra, Yogesh; Weir, Samuel; Tulk, Christopher; Moreira Dos Santos, Antonio

    2013-06-01

    Neutron diffraction and electrical transport measurements have been carried out on the heavy rare earth metal terbium at high pressures and low temperatures in order to elucidate its transition from a helical antiferromagnetic to a ferromagnetic ordered phase as a function of pressure. The electrical resistance measurements using designer diamonds show a change in slope as the temperature is lowered through the ferromagnetic Curie temperature. The temperature of the ferromagnetic transition decreases at a rate of -16.7 K/GPa till 3.6 GPa, where terbium undergoes a structural transition from hexagonal close packed (hcp) to an α-Sm phase. Above this pressure, the electrical resistance measurements no longer exhibit a change in slope. In order to confirm the change in magnetic phase suggested by the electrical resistance measurements, neutron diffraction measurements were conducted at the SNAP beamline at the Oak Ridge National Laboratory. Measurements were made at pressures to 5.3 GPa and temperatures as low as 90 K. An abrupt increase in peak intensity in the neutron diffraction spectra signaled the onset of magnetic order below the Curie temperature. A magnetic phase diagram of rare earth metal terbium will be presented to 5.3 GPa and 90 K based on these studies.

  20. Iodide and albumin kinetics in normal canine wrists and knees

    Energy Technology Data Exchange (ETDEWEB)

    Simkin, P.A.; Benedict, R.S. (Univ. of Washington, Seattle (USA))

    1990-01-01

    The clearance rates of free iodide and of radioiodinated serum albumin were measured in the knee and wrist joints of 9 normal adult dogs. Iodide clearance from the knee was 3 times greater than that from the wrist. In contrast, radioiodinated serum albumin clearance from the knee was only slightly greater than that from the wrist. Interpreted as respective indices of effective synovial plasma flow and lymphatic drainage, these values indicate that the filtration fraction is normally greater in microvessels of the wrist than in those of the knee. These findings complement the results of companion studies of Starling forces that indicate a higher pressure microvascular bed in the wrist than in the knee.

  1. FY-2016 Methyl Iodide Higher NOx Adsorption Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Soelberg, Nicholas Ray [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony Leroy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    Deep-bed methyl iodide adsorption testing has continued in Fiscal Year 2016 under the Department of Energy (DOE) Fuel Cycle Technology (FCT) Program Offgas Sigma Team to further research and advance the technical maturity of solid sorbents for capturing iodine-129 in off-gas streams during used nuclear fuel reprocessing. Adsorption testing with higher levels of NO (approximately 3,300 ppm) and NO2 (up to about 10,000 ppm) indicate that high efficiency iodine capture by silver aerogel remains possible. Maximum iodine decontamination factors (DFs, or the ratio of iodine flowrate in the sorbent bed inlet gas compared to the iodine flowrate in the outlet gas) exceeded 3,000 until bed breakthrough rapidly decreased the DF levels to as low as about 2, when the adsorption capability was near depletion. After breakthrough, nearly all of the uncaptured iodine that remains in the bed outlet gas stream is no longer in the form of the original methyl iodide. The methyl iodide molecules are cleaved in the sorbent bed, even after iodine adsorption is no longer efficient, so that uncaptured iodine is in the form of iodine species soluble in caustic scrubber solutions, and detected and reported here as diatomic I2. The mass transfer zone depths were estimated at 8 inches, somewhat deeper than the 2-5 inch range estimated for both silver aerogels and silver zeolites in prior deep-bed tests, which had lower NOx levels. The maximum iodine adsorption capacity and silver utilization for these higher NOx tests, at about 5-15% of the original sorbent mass, and about 12-35% of the total silver, respectively, were lower than for trends from prior silver aerogel and silver zeolite tests with lower NOx levels. Additional deep-bed testing and analyses are recommended to expand the database for organic iodide adsorption and increase the technical maturity if iodine adsorption processes.

  2. Absence of ferroelectricity in methylammonium lead iodide perovskite

    Directory of Open Access Journals (Sweden)

    Mohammad Sajedi Alvar

    2017-09-01

    Full Text Available Ferroelectricity has been proposed as one of the potential origins of the observed hysteresis in photocurrent-voltage characteristics of perovskite based solar cells. Measurement of ferroelectric properties on perovskite solar cells is hindered by the presence of (inorganic charge transport layers. Here we fabricate metal-perovskite-metal capacitors and unambiguously show that methylammonium lead iodide is not ferroelectric at room temperature. We propose that the hysteresis originates from the movement of positive ions rather than ferroelectric switching.

  3. Automatic titrimetric determination of iodide in some pharmaceutical contrasting preparations.

    Science.gov (United States)

    Abramović, B; Horváth, K; Gaál, F

    1993-06-01

    Automatic titrimetric methods with catalytic, spectrophotometric and potentiometric monitoring of the course of titration were applied for determination of iodide content in iopanoic acid, 2-(3-amino-2,4,6-tri-iodobenzyl)butyric acid, as well as in the mixture of sodium amidotrizoate (sodium 3,5-diacetamido-2,4,6-tri-iodobenzoate), and meglumine amidotrizoate (N-methylglucamine salt of 3,5-diacetamido-2,4,6-tri-iodobenzoic acid), in some pharmaceutical contrasting preparations. After combustion of the sample in an oxygen atmosphere and absorption of products in hydrazine sulphate solution, the iodide present was titrated with a standard solution of silver nitrate. In catalytic titrations, the system persulphate-sulphanilic acid (acetate buffer pH 4.35) in the presence of 2,2'-bipyridine as an activator served as the indicator reaction. The results obtained were compared with those of the official methods. Amounts of iodide of about 1.2 mg per aliquot of analyte were determined with a standard deviation less than 1.9%.

  4. Laccase-catalyzed oxidation of iodide and formation of organically bound iodine in soils.

    Science.gov (United States)

    Seki, Miharu; Oikawa, Jun-ichi; Taguchi, Taro; Ohnuki, Toshihiko; Muramatsu, Yasuyuki; Sakamoto, Kazunori; Amachi, Seigo

    2013-01-02

    Laccase oxidizes iodide to molecular iodine or hypoiodous acid, both of which are easily incorporated into natural soil organic matter. In this study, iodide sorption and laccase activity in 2 types of Japanese soil were determined under various experimental conditions to evaluate possible involvement of this enzyme in the sorption of iodide. Batch sorption experiment using radioactive iodide tracer ((125)I(-)) revealed that the sorption was significantly inhibited by autoclaving (121 °C, 40 min), heat treatment (80 and 100 °C, 10 min), γ-irradiation (30 kGy), N(2) gas flushing, and addition of reducing agents and general laccase inhibitors (KCN and NaN(3)). Interestingly, very similar tendency of inhibition was observed in soil laccase activity, which was determined using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) as a substrate. The partition coefficient (K(d): mL g(-1)) for iodide and specific activity of laccase in soils (Unit g(-1)) showed significant positive correlation in both soil samples. Addition of a bacterial laccase with an iodide-oxidizing activity to the soils strongly enhanced the sorption of iodide. Furthermore, the enzyme addition partially restored iodide sorption capacity of the autoclaved soil samples. These results suggest that microbial laccase is involved in iodide sorption on soils through the oxidation of iodide.

  5. Study of Silver Nanoparticles Sensitized Fluorescence and Second-Order Scattering of Terbium(III-Pefloxacin Mesylate Complex and Determination of Pefloxacin Mesylate

    Directory of Open Access Journals (Sweden)

    Aiyun Li

    2014-01-01

    Full Text Available α-Keto acid of pefloxacin mesylate (PFLX can form the complex with Terbium(III. The intramolecular energy from PFLX to Terbium(III ion takes place when excited, and thus Terbium(III excited state is formed and then emits the characteristic fluorescence of Terbium(III, locating at 490, 545, 580, and 620 nm. The second-order scattering (SOS peak at 545 nm also appears for the complex with the exciting wavelength of 273 nm. When the silver nanoparticles are added to the system, the luminescence intensity at 545 nm greatly increased. So, with the adding of nanoparticles to the Terbium(III-PFLX complex, not only is the intramolecular energy promoted but also the SOS intensity is enhanced. The experimental results show that it is the silver nanoparticles with certain size and certain concentration which can greatly enhance the fluorescence-SOS intensity, and the relative intensity at 545 nm is proportional to the amount of PFLX. Based on this phenomenon, a novel method for the determination of PFLX has been developed and applied to the determination of PFLX in capsule and serum samples.

  6. Influence of crystalline structure on the luminescence properties of terbium orthotantalates

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Kisla P.F. [Departamento de Química, Universidade Federal de Ouro Preto, Campus Morro do Cruzeiro, ICEB II, Ouro Preto 35400-000, Minas Gerais (Brazil); Carmo, Alexandre P. [Instituto Federal Fluminense, Campus Cabo Frio, RJ 28909-971 (Brazil); Bell, Maria J.V. [Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora 36036-330, MG (Brazil); Dias, Anderson, E-mail: anderson_dias@iceb.ufop.br [Departamento de Química, Universidade Federal de Ouro Preto, Campus Morro do Cruzeiro, ICEB II, Ouro Preto 35400-000, Minas Gerais (Brazil)

    2013-06-15

    Terbium orthotantalate powders were produced with M-fergusonite type (I2/a) and M′-fergusonite type (P2/a) structures. The samples were studied by X-ray diffraction, Raman scattering, and photoluminescence measurements (emission and decay curves). The results showed that crystalline materials were obtained with all the 18 Raman-active modes predicted by group theory calculations. Also, it was observed through photoluminescence decay curves that the Tb{sup 3+} ions occupies only one-symmetry site in both crystallographic arrangements. Photoluminescence emission curves exhibited some variation in spectral shape, peak position, and relative intensity as a consequence of their different crystalline arrangements. The dominated emission of Tb{sup 3+} ({sup 5}D{sub 4}→{sup 7}F{sub 5}) is centered with a maximum intensity at 549.2 nm (M-type) and 543.0 nm (M′-type). Fluorescence lifetimes for M-TbTaO{sub 4} and M′-TbTaO{sub 4} were determined as 33.4 μs and 1.25 ms, respectively. M′-type materials seems to be the most suitable for luminescent devices and could be a potential green luminescent material due to the strongest emission if compared with the M-fergusonite type. -- Highlights: ► Terbium orthotantalates were prepared in two different crystalline structures: I2/a and P2/a. ► XRD and Raman scattering showed that the different space groups obtained were exhibited all the 18 Raman-active modes. ► PL decay curves that the Tb{sup 3+} ions occupies only one-symmetry site in both crystallographic arrangements. ► Dominated emission of Tb{sup 3+} ({sup 5}D{sub 4}→{sup 7}F{sub 5}) is centered with a maximum intensity at 549 nm (M-type) and 543 nm (M′-type). ► Fluorescence lifetimes for M-TbTaO{sub 4} and M′-TbTaO{sub 4} were determined as 33.4 μs and 1.25 ms, respectively.

  7. Electrodeposition as an alternate method for preparation of environmental samples for iodide by AMS

    Energy Technology Data Exchange (ETDEWEB)

    Adamic, M.L., E-mail: Mary.Adamic@inl.gov [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83402 (United States); Lister, T.E.; Dufek, E.J.; Jenson, D.D.; Olson, J.E. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83402 (United States); Vockenhuber, C. [Laboratory of Ion Beam Physics, ETH Zurich, Otto-Stern-Weg 5, 8093 Zurich (Switzerland); Watrous, M.G. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83402 (United States)

    2015-10-15

    This paper presents an evaluation of an alternate method for preparing environmental samples for {sup 129}I analysis by accelerator mass spectrometry (AMS) at Idaho National Laboratory. The optimal sample preparation method is characterized by ease of preparation, capability of processing very small quantities of iodide, and ease of loading into a cathode. Electrodeposition of iodide on a silver wire was evaluated using these criteria. This study indicates that the electrochemically-formed silver iodide deposits produce ion currents similar to those from precipitated silver iodide for the same sample mass. Precipitated silver iodide samples are usually mixed with niobium or silver powder prior to loading in a cathode. Using electrodeposition, the silver is already mixed with the sample and can simply be picked up with tweezers, placed in the sample die, and pressed into a cathode. The major advantage of this method is that the silver wire/electrodeposited silver iodide is much easier to load into a cathode.

  8. Laser control and temperature switching of luminescence intensity in photostable transparent film based on terbium(III) β-diketonate complex

    Science.gov (United States)

    Lapaev, Dmitry V.; Nikiforov, Victor G.; Safiullin, Georgy M.; Lobkov, Vladimir S.; Salikhov, Kev M.; Knyazev, Andrey A.; Galyametdinov, Yury G.

    2014-11-01

    The study of the terbium(III) and gadolinium(III) β-diketonate complexes by photoluminescence spectroscopy reveals considerable changes of the photophysical properties of the complexes under the UV laser irradiation. The measurements show the enhancement of the luminescence intensities in the vitrified transparent film of the terbium(III) complex as well as the gadolinium(III) complex under the 337 nm laser irradiation at room temperature. The irradiated film of the terbium(III) complex restores the initial photophysical properties after heating close to the melting temperature (∼353 K) and cooling. We observe no change of the luminescent properties of the irradiated film for months. These features can be used for the design of new lanthanide-based photostable systems with laser control of the luminescence intensity.

  9. 6 Iodo-delta-lactone reproduces many but not all the effects of iodide.

    Science.gov (United States)

    Thomasz, Lisa; Oglio, Romina; Dagrosa, María A; Krawiec, León; Pisarev, Mario A; Juvenal, Guillermo J

    2010-07-29

    Iodide has direct effects on thyroid function. Several iodinated lipids are biosynthesized by the thyroid and they were postulated as intermediaries in the action of iodide. Among them 6 iodo-delta-lactone (IL-delta) has been identified and proposed to play a role in thyroid autoregulation. The aim of this study was to compare the effect of iodide and IL-delta on several thyroid parameters. Thyroid bovine follicles were incubated with the different compounds during three days. KI and IL-delta inhibited iodide uptake, total protein and Tg synthesis but only KI had an effect on NIS and Tg mRNAs levels. Both compounds inhibited Na+/K+ ATPase and deoxy-glucose uptake. As PAX 8, FOXE 1 and TITF1 are involved in the regulation of thyroid specific genes their mRNA levels were measured. While iodide inhibited the expression of the first two, the expression of TITF1 was stimulated by iodide and IL-delta had no effect on these parameters. These findings indicate that IL-delta reproduces some but not all the effects of excess iodide. These observations apply for higher micromolar concentrations of iodide while no such effects could be demonstrated at nanomolar iodide concentrations. 2010 Elsevier Ireland Ltd. All rights reserved.

  10. Methyl Iodide Exposure Presenting as Severe Chemical Burn Injury with Neurological Complications and Prolonged Respiratory Insufficiency.

    Science.gov (United States)

    Held, Manuel; Medved, Fabian; Rothenberger, Jens; Rahmanian-Schwarz, Afshin; Schaller, Hans-Eberhard

    Methyl iodide (iodomethane) is a monohalomethane that is mainly used as an intermediate in the manufacturing of different pharmaceuticals and pesticides. Until now, only 13 cases of methyl iodide poisoning have been described in the literature. The authors present the first case of severe chemical burn injury due to methyl iodide exposure in a 36-year-old Caucasian man who suffered superficial to partial-thickness burn injuries over 75% of his BSA and developed neurological malfunctions and prolonged respiratory insufficiency. Human poisoning with methyl iodide is very rare. In addition to the already described neurological symptoms and respiratory insufficiency, severe chemical burn injury can cause a life-threatening medical emergency.

  11. Development of functionalized terbium fluorescent nanoparticles for antibody labeling and time-resolved fluoroimmunoassay application.

    Science.gov (United States)

    Ye, Zhiqiang; Tan, Mingqian; Wang, Guilan; Yuan, Jingli

    2005-01-15

    Silica-based functionalized terbium fluorescent nanoparticles were prepared, characterized and developed as a fluorescence probe for antibody labeling and time-resolved fluoroimmunoassay. The nanoparticles were prepared in a water-in-oil (W/O) microemulsion containing a strongly fluorescent Tb(3+) chelate, N,N,N(1),N(1)-[2,6-bis(3'-aminomethyl-1'-pyrazolyl)phenylpyridine] tetrakis(acetate)-Tb(3+) (BPTA-Tb(3+)), Triton X-100, octanol, and cyclohexane by controlling copolymerization of tetraethyl orthosilicate (TEOS) and 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethoxysilane (AEPS) with ammonia water. The characterizations by transmission electron microscopy and fluorometric methods show that the nanoparticles are spherical and uniform in size, 45 +/- 3nm in diameter, strongly fluorescent with fluorescence quantum yield of 10% and a long fluorescence lifetime of 2.0ms. The amino groups directly introduced to the nanoparticle's surface by using AEPS in the preparation made the surface modification and bioconjugation of the nanoparticles easier. The nanoparticle-labeled anti-human alpha-fetoprotein antibody was prepared and used for time-resolved fluoroimmunoassay of alpha-fetoprotein (AFP) in human serum samples. The assay response is linear from 0.10ngml(-1) to about 100ngml(-1) with the detection limit of 0.10ngml(-1). The coefficient variations (CVs) of the method are less than 9.0%, and the recoveries are in the range of 84-98% for human serum sample measurements.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-05-15

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

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

    Directory of Open Access Journals (Sweden)

    Salma M.Z. Al-Kindy

    2014-12-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-04-15

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

  15. A Nanoscale Multiresponsive Luminescent Sensor Based on a Terbium(III) Metal-Organic Framework.

    Science.gov (United States)

    Dang, Song; Wang, Ting; Yi, Feiyan; Liu, Qinghui; Yang, Weiting; Sun, Zhong-Ming

    2015-08-01

    A nanoscale terbium-containing metal-organic framework (nTbL), with a layer-like structure and [H2 NMe2 ](+) cations located in the framework channels, was synthesized under hydrothermal conditions. The structure of the as-prepared sample was systematically confirmed by powder XRD and elemental analysis; the morphology was characterized by field-emission SEM and TEM. The photoluminescence studies revealed that rod-like nTbL exhibited bright-green emission, corresponding to (5)D4 →(7)FJ (J=6-3) transitions of the Tb(3+) ion under excitation. Further sensing measurements revealed that as-prepared nTbL could be utilized as a multiresponsive luminescent sensor, which showed significant and exclusive detection ability for Fe(3+) ions and phenylmethanol. These results highlight the practical applications of lanthanide-containing metal-organic frameworks as fluorescent probes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Terbium-Doped VO2 Thin Films: Reduced Phase Transition Temperature and Largely Enhanced Luminous Transmittance.

    Science.gov (United States)

    Wang, Ning; Duchamp, Martial; Dunin-Borkowski, Rafal E; Liu, Shiyu; Zeng, XianTing; Cao, Xun; Long, Yi

    2016-01-26

    Vanadium dioxide (VO2) is a well-known thermochromic material with large IR modulating ability, promising for energy-saving smart windows. The main drawbacks of VO2 are its high phase transition temperature (τ(c) = 68°C), low luminous transmission (T(lum)), and weak solar modulating ability (ΔT(sol)). In this paper, the terbium cation (Tb(3+)) doping was first reported to reduce τ(c) and increase T(lum) of VO2 thin films. Compared with pristine VO2, 2 at. % doping level gives both enhanced T(lum) and ΔT(sol) from 45.8% to 54.0% and 7.7% to 8.3%, respectively. The T(lum) increases with continuous Tb(3+) doping and reaches 79.4% at 6 at. % doping level, representing ∼73.4% relative increment compared with pure VO2. This has surpassed the best reported doped VO2 thin films. The enhanced thermochromic properties is meaningful for smart window applications of VO2 materials.

  17. Luminescent investigations of terbium(III) biosorption as a surrogate for heavy metals and radionuclides.

    Science.gov (United States)

    Achyuthan, Komandoor E; Arango, Dulce C; Carles, Elizabeth L; Cutler, Christopher E; Meyer, Lauren A; Brozik, Susan M

    2009-07-01

    We describe a metal transport system for investigating the interfacial interactions between the anionic surface charge of a gram-negative bacterium (Escherichia coli) and a trivalent cationic metal, Tb3+. We believe this is the first description of the uptake kinetics, sub- and intracellular distribution, and temporal fate of Tb3+ ion in E. coli. We used the luminescence of the terbium-dipicolinic acid chelate to study metal ion transport. The bacteria had a high tolerance for the metal (IC(50) = 4 mM Tb3+). Metal ion transport was passive and metabolism independent. The uptake kinetics rapidly reached a maximum within 15 min, followed by a stasis for 60 min, and declining thereafter between 120 and 240 min, resulting in a biphasic curve. During this period, greater than one-third of the metal ion was sequestered within the cell. Our choice of a safe Biosafety Level I E. coli bacteria and the relatively non-toxic Tb3+ metal represents a model system for luminescent investigations of biosorption, for studying bacterial-water interfacial chemistry and for the bioremediation of heavy metals and radionuclides.

  18. 1-(Ferrocen-1-ylmethyl-3-methylimidazol-3-ium iodide

    Directory of Open Access Journals (Sweden)

    Vincent O. Nyamori

    2012-12-01

    Full Text Available The structure of the title compound, [Fe(C5H5(C10H12N2]I, consists of a 1-(ferrocen-1-ylmethyl-3-methylimidazolium cation which is counter-balanced by an iodide anion. The cyclopentadienyl (Cp rings of the ferrocene unit have a slightly staggered conformation skewed from an ideal eclipsed conformation by an angle of 3.5 (6°. The interplanar angle between the Cp and the imidazole ring is 67.94 (2°.

  19. Nuclear detonation, thyroid cancer and potassium iodide prophylaxis

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2011-01-01

    Full Text Available The recent nuclear disaster at Japan has raised global concerns about effects of radioactive leakage in the environment, associated hazards, and how they can be prevented. In this article, we have tried to explain about the guidelines laid down by World Health Organization for a potassium iodide prophylaxis following a nuclear disaster, and its mechanism of action in preventing thyroid cancer. Data was collected mainly from the studies carried out during the Chernobyl disaster of Russia in 1986 and the hazardous effects especially on the thyroid gland were studied. It was seen that radioactive iodine leakage from the nuclear plants mainly affected the thyroid gland, and especially children were at a higher risk at developing the cancers. Potassium Iodide prophylaxis can be administered in order to prevent an increase in the incidence of thyroid cancers in the population of an area affected by a nuclear disaster. However, one has to be cautious while giving it, as using it without indication has its own risks.

  20. Numerical modelling of methyl iodide in the eastern tropical Atlantic

    Directory of Open Access Journals (Sweden)

    I. Stemmler

    2013-06-01

    Full Text Available Methyl iodide (CH3I is a volatile organic halogen compound that contributes significantly to the transport of iodine from the ocean to the atmosphere, where it plays an important role in tropospheric chemistry. CH3I is naturally produced and occurs in the global ocean. The processes involved in the formation of CH3I, however, are not fully understood. In fact, there is an ongoing debate whether production by phytoplankton or photochemical degradation of organic matter is the main source term. Here, both the biological and photochemical production mechanisms are considered in a biogeochemical module that is coupled to a one-dimensional water column model for the eastern tropical Atlantic. The model is able to reproduce observed subsurface maxima of CH3I concentrations. But, the dominating source process cannot be clearly identified as subsurface maxima can occur due to both direct biological and photochemical production. However, good agreement between the observed and simulated difference between surface and subsurface methyl iodide concentrations is achieved only when direct biological production is taken into account. Production rates for the biological CH3I source that were derived from published laboratory studies are shown to be inappropriate for explaining CH3I concentrations in the eastern tropical Atlantic.

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

    Science.gov (United States)

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

    2017-11-01

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

  2. Thyroid hormones and iodide in the near-term pregnant rat

    NARCIS (Netherlands)

    Versloot, P.

    1998-01-01

    Thyroid hormones, thyroxine (T4) and 3,5,3'-triiodothyronine (T3), are produced by the thyroid gland. To synthesize thyroid hormones the thyroid needs iodide. The uptake of iodide as well as the production and secretion of T4 and T3 by the thyroid gland is regulated by thyrotropin (TSH),

  3. Oxygen-hydrogen fuel cell with an iodine-iodide cathode - A concept

    Science.gov (United States)

    Javet, P.

    1970-01-01

    Fuel cell uses a porous cathode through which is fed a solution of iodine in aqueous iodide solution, the anode is a hydrogen electrode. No activation polarization appears on the cathode because of the high exchange-current density of the iodine-iodide electrode.

  4. Effects of radiation and temperature on iodide sorption by surfactant-modified bentonite.

    Science.gov (United States)

    Choung, Sungwook; Kim, Minkyung; Yang, Jung-Seok; Kim, Min-Gyu; Um, Wooyong

    2014-08-19

    Bentonite, which is used as an engineered barrier in geological repositories, is ineffective for sorbing anionic radionuclides because of its negatively charged surface. This study modified raw bentonite using a cationic surfactant (i.e., hexadecyltrimethylammonium [HDTMA]-Br) to improve its sorption capability for radioactive iodide. The effects of temperature and radiation on the iodide sorption of surfactant-modified bentonite (SMB) were also evaluated under alkaline pH condition similar to that found in repository environments. Different amounts of surfactant, equivalent to the 50, 100, and 200% cation-exchange capacity of the bentonite, were used to produce the HDTMA-SMB for iodide sorption. The sorption reaction of the SMB with iodide reached equilibrium rapidly within 10 min regardless of temperature and radiation conditions. The rate of iodide sorption increased as the amount of the added surfactant was increased and nonlinear sorption behavior was exhibited. However, high temperature and γ-irradiation ((60)Co) resulted in significantly (∼2-10 times) lower iodide Kd values for the SMB. The results of FTIR, NMR, and XANES spectroscopy analysis suggested that the decrease in iodide sorption may be caused by weakened physical electrostatic force between the HDTMA and iodide, and by the surfactant becoming detached from the SMB during the heating and irradiation processes.

  5. Spectrofluorimetric determination of human serum albumin using terbium-danofloxacin probe.

    Science.gov (United States)

    Ramezani, Amir M; Manzoori, Jamshid L; Amjadi, Mohammad; Jouyban, Abolghasem

    2012-01-01

    A spectrofluorimetric method is proposed for the determination of human serum albumin (HSA) and bovine serum albumin (BSA) using terbium-danofloxacin (Tb(3+)-Dano) as a fluorescent probe. These proteins remarkably enhance the fluorescence intensity of the Tb(3+)-Dano complex at 545 nm, and the enhanced fluorescence intensity of Tb(3+)-Dano is proportional to the concentration of proteins (HSA and BSA). Optimum conditions for the determination of HSA were investigated and found that the maximum response was observed at: pH = 7.8, [Tb(3+)] = 8.5 × 10(-5) mol L(-1), [Dano] = 1.5 × 10(-4) mol L(-1). The calibration graphs for standard solutions of BSA, HSA, and plasma samples of HSA were linear in the range of 0.2 × 10(-6) - 1.3 × 10(-6) mol L(-1), 0.2 × 10(-6) - 1.4 × 10(-6) mol L(-1), and 0.2 × 10(-6) - 1 × 10(-6) mol L(-1), respectively. The detection limits (S/N = 3) for BSA, HSA, and plasma sample of HSA were 8.7 × 10(-8) mol L(-1), 6.2 × 10(-8) mol L(-1), and 8.1 × 10(-8) mol L(-1), respectively. The applicability of the method was checked using a number of real biological plasma samples and was compared with the UV spectrometric reference method. The results was showed that the method could be regarded as a simple, practical, and sensitive alternative method for determination of albumin in biological samples.

  6. Spectrofluorimetric Determination of Human Serum Albumin Using Terbium-Danofloxacin Probe

    Directory of Open Access Journals (Sweden)

    Amir M. Ramezani

    2012-01-01

    Full Text Available A spectrofluorimetric method is proposed for the determination of human serum albumin (HSA and bovine serum albumin (BSA using terbium-danofloxacin (Tb3+-Dano as a fluorescent probe. These proteins remarkably enhance the fluorescence intensity of the Tb3+-Dano complex at 545 nm, and the enhanced fluorescence intensity of Tb3+-Dano is proportional to the concentration of proteins (HSA and BSA. Optimum conditions for the determination of HSA were investigated and found that the maximum response was observed at: pH=7.8, [Tb3+] =8.5×10−5 mol L−1, [Dano] =1.5×10−4 mol L−1. The calibration graphs for standard solutions of BSA, HSA, and plasma samples of HSA were linear in the range of 0.2×10−6−1.3×10−6 mol L−1, 0.2×10−6−1.4×10−6 mol L−1, and 0.2×10−6−1×10−6 mol L−1, respectively. The detection limits (S/N = 3 for BSA, HSA, and plasma sample of HSA were 8.7×10−8 mol L−1, 6.2×10−8 mol L−1, and 8.1×10−8 mol L−1, respectively. The applicability of the method was checked using a number of real biological plasma samples and was compared with the UV spectrometric reference method. The results was showed that the method could be regarded as a simple, practical, and sensitive alternative method for determination of albumin in biological samples.

  7. Determination of flavonoids in pharmaceutical preparations using Terbium sensitized fluorescence method

    Directory of Open Access Journals (Sweden)

    M Shaghaghi

    2009-12-01

    Full Text Available "nBackground and the Purpose of the Study: The aim of this study was development and validation of a simple, rapid and sensitive spectrofluorimetric method for determination of total flavonoids in two topical formulations of Calendula officinalis, Ziziphus Spina-christi and an oral drop of Hypiran perforatum L. The proposed method is based on the formation of terbium (Tb3+ "n-flavonoids (quercetin as a reference standard complex at pH 7.0, which has fluorescence intensely with maximum emission at 545 nm when excited at 310 nm. "nMethod "n: For ointments masses of topical formulations were weighed and added to ethanol-aqueous buffer (pH 10.0 and the resulting mixtures were shaken and then two phases were separated by centrifugation. Aqueous phases were filtered and then diluted with water. For Hypiran drops an appropriate portion was diluted with ethanol and then aliquots of sample or standard solutions were determined according to the experimental procedure. "nResults "n: Under the optimum conditions, total concentrations of flavonoids (as quercetin equivalent in three tested formulations were found to be 0.204 mg/g (for Dermatin cream, 0.476 mg/g (for Calendula ointment and 13.50 μg/ml (for Hypiran drops. Analytical recoveries from samples spiked with different amounts of quercetin were 96.1-104.0 % with RSD % of less than 3.5. Conclusion : The proposed method which requires a simple dissolution step without any matrix interferences provided high sensitivity and selectivity and was easily applied to determine total flavonoids in real samples of three investigated formulations with excellent reproducibility.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-03-15

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

  9. Linking loss of sodium-iodide symporter expression to DNA damage

    Energy Technology Data Exchange (ETDEWEB)

    Lyckesvärd, Madeleine Nordén [Sahlgrenska Cancer Center, University of Gothenburg, Göteborg (Sweden); Department of Medical Chemistry and Cell Biology, University of Gothenburg, Göteborg (Sweden); Kapoor, Nirmal [Department of Medical Chemistry and Cell Biology, University of Gothenburg, Göteborg (Sweden); Ingeson-Carlsson, Camilla; Carlsson, Therese [Sahlgrenska Cancer Center, University of Gothenburg, Göteborg (Sweden); Department of Medical Chemistry and Cell Biology, University of Gothenburg, Göteborg (Sweden); Karlsson, Jan-Olof [Department of Medical Chemistry and Cell Biology, University of Gothenburg, Göteborg (Sweden); Postgård, Per; Himmelman, Jakob; Forssell-Aronsson, Eva [Department of Radiation Physics, University of Gothenburg, Göteborg (Sweden); Hammarsten, Ola [Department of Clinical Chemistry, University of Gothenburg, Göteborg (Sweden); Nilsson, Mikael, E-mail: mikael.nilsson@gu.se [Sahlgrenska Cancer Center, University of Gothenburg, Göteborg (Sweden); Department of Medical Chemistry and Cell Biology, University of Gothenburg, Göteborg (Sweden)

    2016-05-15

    Radiotherapy of thyroid cancer with I-131 is abrogated by inherent loss of radioiodine uptake due to loss of sodium iodide symporter (NIS) expression in poorly differentiated tumor cells. It is also known that ionizing radiation per se down-regulates NIS (the stunning effect), but the mechanism is unknown. Here we investigated whether loss of NIS-mediated iodide transport may be elicited by DNA damage. Calicheamicin, a fungal toxin that specifically cleaves double-stranded DNA, induced a full scale DNA damage response mediated by the ataxia-telangiectasia mutated (ATM) kinase in quiescent normal thyrocytes. At sublethal concentrations (<1 nM) calicheamicin blocked NIS mRNA expression and transepithelial iodide transport as stimulated by thyrotropin; loss of function occurred at a much faster rate than after I-131 irradiation. KU-55933, a selective ATM kinase inhibitor, partly rescued NIS expression and iodide transport in DNA-damaged cells. Prolonged ATM inhibition in healthy cells also repressed NIS-mediated iodide transport. ATM-dependent loss of iodide transport was counteracted by IGF-1. Together, these findings indicate that NIS, the major iodide transporter of the thyroid gland, is susceptible to DNA damage involving ATM-mediated mechanisms. This uncovers novel means of poor radioiodine uptake in thyroid cells subjected to extrinsic or intrinsic genotoxic stress. - Highlights: • DNA damage inhibits polarized iodide transport in normal thyroid cells. • Down-regulation of NIS expression is mediated by activation of the ATM kinase. • Long-term ATM inhibition also represses NIS-mediated iodide transport. • IGF-1 rescues NIS expression and iodide transport in DNA-damaged cells.

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

    NARCIS (Netherlands)

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

    2007-01-01

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

  11. Zinc sulfide and terbium-doped zinc sulfide films grown by traveling wave reactor atomic layer epitaxy

    CERN Document Server

    Yun, S J; Nam, K S

    1998-01-01

    Zinc sulfide (ZnS) and terbium-doped ZnS (ZnS:Tb) thin films were grown by traveling wave reactor atomic layer epitaxy (ALE). In the present work, ZnCl sub 2 , H sub 2 S, and tris (2,2,6,6-tetramethyl-3,5-heptandionato) terbium (Tb(tmhd) sub 3) were used as the precursors. The dependence of crystallinity and Cl content of ZnS films was investigated on the growth temperature. ZnS and ZnS:Tb films grown at temperatures ranging from 400 to 500 .deg. C showed a hexagonal-2H crystalline structure. The crystallinity of ZnS film was greatly enhanced as the temperature increased. At growth temperatures higher than 450.deg.C, the films showed preferred orientation with mainly (002) diffraction peak. The Cl content decreased from approximately 9 to 1 at.% with the increase in growth temperature from 400 to 500 .deg. C. The segregation of Cl near the surface region and the incorporation of O from Tb(tmhd) sub 3 during ALE process were also observed using Auger electron spectroscopy. The ALE-grown ZnS and ZnS:Tb films re...

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

    Science.gov (United States)

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

    2017-10-01

    Many scientific lasers and increasingly industrial laser systems operate in power regime, require high-performance optical isolators to prevent disruptive light feedback into the laser cavity. The optically active Faraday material is the key optical element inside the isolator. SYNOPTICS has been supplying the laser market with Terbium Gallium Garnet (TGG - Tb3Ga5O12) for many years. It is the most commonly used material for the 650-1100nm range and the key advantages for TGG include its cubic crystal structure for alignment free processing, little to no intrinsic birefringence, and ease of manufacture. However, for high-power laser applications TGG is limited by its absorption at 1064nm and its thermo-optic coefficient, dn/dT. Specifically, thermal lensing and depolarization effects become a limiting factor at high laser powers. While TGG absorption has improved significantly over the past few years, there is an intrinsic limit. Now, SYNOPTICS is commercializing the enhanced new crystal Potassium Terbium Fluoride KTF (KTb3F10) that exhibits much smaller nonlinear refractive index and thermo-optic coefficients, and still exhibits a Verdet constant near that of TGG. This cubic crystal has relatively low absorption and thermo-optic coefficients. It is now fully characterized and available for select production orders. At OPTIFAB in October 2017 we present recent results comparing the performance of KTF to TGG in optical isolators and show SYNOPTICS advances in large volume crystal growth and the production ramp up.

  13. Preparation and photoluminescence enhancement in terbium(III ternary complexes with β-diketone and monodentate auxiliary ligands

    Directory of Open Access Journals (Sweden)

    Devender Singh

    2016-12-01

    Full Text Available A series of new solid ternary complexes of terbium(III ion based on β-diketone ligand acetylacetone (acac and monodentate auxiliary ligands (aqua/urea/triphenylphosphineoxide/pyridine-N-oxide had been prepared. The structural characterizations of synthesized ternary compounds were studied by means of elemental analysis, infrared (IR, and proton nuclear magnetic resonance (NMR spectral techniques. The optical characteristics were investigated with absorption as well as photoluminescence spectroscopy. Thermal behavior of compounds was examined by TGA/DTA analysis and all metal complexes were found to have good thermal stability. The luminescence decay time of complexes were also calculated by monitoring at emission wavelength corresponding to 5D4 → 7F5 transition. A comparative inspection of the luminescent behavior of prepared ternary compounds was performed in order to determine the function of auxiliary ligands in the enhancement of luminescence intensity produced by central terbium(III ion. The color coordinates values suggested that compounds showed bright green emission in visible region in electromagnetic spectrum. Complexes producing green light could play a significant role in the fabrication of efficient light conversion molecular devices for display purposes and lightning systems.

  14. Methodology for assaying iodide conductance in proteoliposomes: specific induction by thyroid membrane protein.

    Science.gov (United States)

    Golstein, P E; Sener, A; Beauwens, R

    1995-12-01

    A sensitive assay is developed to assess the existence of an iodide channel in a fraction of solubilized membrane proteins. This step is critical when considering various procedures for purification of this channel. Sodium cholate is used as a detergent as it does not denature the iodide channel. A simple and rapid method involving gel-filtration chromatography is used simultaneously to remove the detergent and to adjust the buffer composition, before protein insertion into liposomes. The presence of an iodide channel is investigated by measuring the iodide conductance of these proteoliposomes at 4 degrees C. An outward iodide gradient is set up across the proteoliposomal membrane by anion-exchange chromatography, allowing uptake of radiolabelled iodide. This uptake is conductive as it is abolished by valinomycin in the presence of potassium. It is specifically mediated by a thyroid plasma-membrane protein inserted into liposomes, as its denaturation before insertion totally abolished uptake. It was observed only within a well-defined fraction of thyroid membrane proteins collected by size-exclusion chromatography (molecular mass between 100 and 200 kDa). Furthermore, it was not observed with other membrane proteins such as ileal brush-border-membrane proteins or bacteriorhodopsin. Like many anion channels, this conductance was also inhibited by N-phenylanthranilic acid. Optimization of the assay is described, validating the measurement of conductive iodide uptake at 30 s by proteoliposomes reconstituted in a ratio of 10 micrograms of protein to 90 micrograms of lipid, with an outward iodide gradient (KI 15 mM inside and 1 microM outside). This assay provides a test of the biological activity of the iodide channel at each step of the purification; it can be applied to any anionic channel.

  15. Synthesis and luminescent study of Ce{sup 3+}-doped terbium-yttrium aluminum garnet

    Energy Technology Data Exchange (ETDEWEB)

    Dotsenko, V.P., E-mail: ssclab@ukr.net [A.V. Bogatsky Physico-Chemical Institute, National Academy of Sciences of Ukraine, Lustdorfskaya doroga 86, 65080 Odessa (Ukraine); Berezovskaya, I.V.; Zubar, E.V.; Efryushina, N.P. [A.V. Bogatsky Physico-Chemical Institute, National Academy of Sciences of Ukraine, Lustdorfskaya doroga 86, 65080 Odessa (Ukraine); Poletaev, N.I.; Doroshenko, Yu.A. [Institute of Combustion and Advanced Technologies, Mechnikov Odessa National University, Dvoryanskaya 2, 65082 Odessa (Ukraine); Stryganyuk, G.B. [Ivan Franko National University of Lviv, Kirilo i Mefodii 8, 79005 Lviv (Ukraine); HASYLAB at DESY, Notkestrasse 85, 22607 Hamburg (Germany); Voloshinovskii, A.S. [Ivan Franko National University of Lviv, Kirilo i Mefodii 8, 79005 Lviv (Ukraine)

    2013-02-15

    Highlights: Black-Right-Pointing-Pointer Ce{sup 3+}-doped garnets (TYAG) were prepared using nanostructured reagents. Black-Right-Pointing-Pointer The Ce{sup 3+} ions cause a very efficient yellow emission of the samples. Black-Right-Pointing-Pointer The reasons for the long wavelength position of this emission are discussed. Black-Right-Pointing-Pointer Contribution from Al atoms to the conduction band of TYAG is quite essential. - Abstract: Terbium-yttrium aluminum garnets (TYAG) doped with Ce{sup 3+} ions have been prepared by solid state reactions between nanostructured oxides of aluminum and rare earths. The luminescent properties of Ce{sup 3+} ions in (Tb{sub 0.8}Y{sub 0.2}){sub 3(1-x)}Ce{sub 3x}Al{sub 5}O{sub 12} (x = 0.03) have been studied upon excitation in the 2-20 eV region. The substitution of Tb{sup 3+} for Y{sup 3+} in the garnet structure results in broadening the emission band and shifting its maximum towards the longer wavelengths. It was found that in addition to the 4f{sup n} {yields} 4f{sup n-1}5d excitation bands of Ce{sup 3+} and Tb{sup 3+} ions, the excitation spectra for the Ce{sup 3+} emission contain broad bands at 6.73 and {approx}9.5 eV. These bands are attributed to the Ce{sup 3+}-bound exciton formation and O 2p {yields} Al 3s, 3p transitions, respectively. In contrast to the predictions based on the results of electronic structure calculations on Y{sub 3}Al{sub 5}O{sub 12} and Tb{sub 4}Al{sub 2}O{sub 9}, the threshold of interband transitions in TYAG is at high energies ( Greater-Than-Or-Slanted-Equal-To 7.3 eV), and contributions from Al{sub tetr} and Al{sub oct} atoms to the conduction-band density of states are evaluated as quite essential.

  16. Structural variations in terbium(III) complexes with 1,3-adamantanedicarboxylate and diverse co-ligands

    Energy Technology Data Exchange (ETDEWEB)

    Thuéry, Pierre, E-mail: pierre.thuery@cea.fr

    2015-07-15

    Terbium nitrate was reacted with 1,3-adamantanedicarboxylic acid (LH{sub 2}) under solvo-hydrothermal conditions with either N,N-dimethylformamide (DMF) or N,N-dimethylacetamide (DMA) as organic solvents. Hydrolysation of the latter co-solvents resulted in the formation of formate or acetate ions, which are present as co-ligands in the 1D coordination polymer [Tb(L)(HCOO)(H{sub 2}O){sub 2}] (1) and the 2D assembly [Tb(L)(CH{sub 3}COO)(H{sub 2}O)] (2). The increase in dimensionality in the latter arises from the higher connectivity provided by acetate versus formate, the L{sup 2−} ligand being bis-chelating in both cases. The complex [Tb{sub 2}(L){sub 3}(H{sub 2}O){sub 5}][Tb{sub 2}(L){sub 3}(H{sub 2}O){sub 4}]·3H{sub 2}O (3), another 1D species, crystallizes alongside crystals of 2. Further addition of cucurbit[6]uril (CB6), with DMF as co-solvent, gave the two complexes [Tb{sub 2}(L){sub 2}(CB6)(H{sub 2}O){sub 6}](NO{sub 3}){sub 2}·6H{sub 2}O (4) and [H{sub 2}NMe{sub 2}]{sub 2}[Tb(L)(HCOO){sub 2}]{sub 2}·CB6·3H{sub 2}O (5). Complex 4 crystallizes as a 3D framework in which Tb(L){sup +} chains are connected by tetradentate CB6 molecules, while 5 unites a carboxylate-bridged anionic 2D planar assembly and layers of CB6 molecules with counter-cations held at both portals. - Graphical abstract: One- to three-dimensional assemblies are formed in terbium(III) complexes with 1,3-adamantanedicarboxylate obtained under solvo-hydrothermal conditions, these species including formate or acetate co-ligands formed in situ, or additional cucurbit[6]uril molecules. - Highlights: • We report structures of terbium(III) complexes with 1,3-adamantanedicarboxylate. • Solvents able to generate co-ligands or counter-ions in situ have been used. • A 3D species including additional cucurbituril molecules is decribed. • One species displays an alternation of metal–organic and organic sheets.

  17. An organic redox electrolyte to rival triiodide/iodide in dye-sensitized solar cells.

    Science.gov (United States)

    Wang, Mingkui; Chamberland, Nathalie; Breau, Livain; Moser, Jacques-E; Humphry-Baker, Robin; Marsan, Benoît; Zakeeruddin, Shaik M; Grätzel, Michael

    2010-05-01

    Dye-sensitized solar cells (DSCs) have achieved impressive conversion efficiencies for solar energy of over 11% with an electrolyte that contains triiodide/iodide as a redox couple. Although triiodide/iodide redox couples work efficiently in DSCs, they suffer from two major disadvantages: electrolytes that contain triiodide/iodide corrode electrical contacts made of silver (which reduces the options for the scale up of DSCs to module size) and triiodide partially absorbs visible light. Here, we present a new disulfide/thiolate redox couple that has negligible absorption in the visible spectral range, a very attractive feature for flexible DSCs that use transparent conductors as current collectors. Using this novel, iodide-free redox electrolyte in conjunction with a sensitized heterojunction, we achieved an unprecedented efficiency of 6.4% under standard illumination test conditions. This novel redox couple offers a viable pathway to develop efficient DSCs with attractive properties for scale up and practical applications.

  18. Application of Mercuric Iodide Detectors to the Monitoring and Evaluation of Stored Special Nuclear Materials

    National Research Council Canada - National Science Library

    van den Berg, L; Proctor, A. E; Pohl, K. R

    2001-01-01

    Mercuric iodide is a very promising material for the monitoring of stored nuclear materials that can be characterized by the energies and relative intensities of the gamma ray spectra that the materials produce...

  19. Slow hot carrier cooling in cesium lead iodide perovskites

    Science.gov (United States)

    Shen, Qing; Ripolles, Teresa S.; Even, Jacky; Ogomi, Yuhei; Nishinaka, Koji; Izuishi, Takuya; Nakazawa, Naoki; Zhang, Yaohong; Ding, Chao; Liu, Feng; Toyoda, Taro; Yoshino, Kenji; Minemoto, Takashi; Katayama, Kenji; Hayase, Shuzi

    2017-10-01

    Lead halide perovskites are attracting a great deal of interest for optoelectronic applications such as solar cells, LEDs, and lasers because of their unique properties. In solar cells, heat dissipation by hot carriers results in a major energy loss channel responsible for the Shockley-Queisser efficiency limit. Hot carrier solar cells offer the possibility to overcome this limit and achieve energy conversion efficiency as high as 66% by extracting hot carriers. Therefore, fundamental studies on hot carrier relaxation dynamics in lead halide perovskites are important. Here, we elucidated the hot carrier cooling dynamics in all-inorganic cesium lead iodide (CsPbI3) perovskite using transient absorption spectroscopy. We observe that the hot carrier cooling rate in CsPbI3 decreases as the fluence of the pump light increases and the cooling is as slow as a few 10 ps when the photoexcited carrier density is 7 × 1018 cm-3, which is attributed to phonon bottleneck for high photoexcited carrier densities. Our findings suggest that CsPbI3 has a potential for hot carrier solar cell applications.

  20. Polycrystalline Mercuric Iodide Films on CMOS Readout Arrays

    Science.gov (United States)

    Hartsough, Neal E.; Iwanczyk, Jan S.; Nygard, Einar; Malakhov, Nail; Barber, William C.; Gandhi, Thulasidharan

    2009-08-01

    We have created high-resolution x-ray imaging devices using polycrystalline mercuric iodide (HgI2) films grown directly onto CMOS readout chips using a thermal vapor transport process. Images from prototype 400 times 400 pixel HgI2-coated CMOS readout chips are presented, where the pixel grid is 30 mum times 30 mum. The devices exhibited sensitivity of 6.2 muC/Rcm2 with corresponding dark current of 2.7 nA/cm2, and a 80 mum FWHM planar image response to a 50 mum slit aperture. X-ray CT images demonstrate a point spread function sufficient to obtain a 50 mum spatial resolution in reconstructed CT images at a substantially reduced dose compared to phosphor-coated readouts. The use of CMOS technology allows for small pixels (30 mum), fast readout speeds (8 fps for a 3200 times 3200 pixel array), and future design flexibility due to the use of well-developed fabrication processes.

  1. A simple sperm nuclear vacuole assay with propidium iodide.

    Science.gov (United States)

    Zhu, W-J; Li, J

    2015-09-01

    Our aim was to develop a new simple sperm nuclear vacuole assay (SNVA) with propidium iodide (PI) to determine the status of nuclear vacuole (NV) of individual spermatozoa. After PI staining, sperm nuclei were classified into the 14 categories according to both nuclear morphology and the status of NV. The incidence was 57.8% (range 28-84%) in fertile controls (n = 40), and 85.1% (range 67-99%) in men with varicocele (n = 40). In the fertile group, normal nuclear-shaped spermatozoa without NV or with one small NV located in the ante-nuclear region were significantly more in comparison with the varicocele group. In the varicocele group, abnormal nuclear-shaped spermatozoa with one large NV and with multiple NVs located in the ante-nuclear region were most frequent findings. Besides, spermatozoa with NVs in both ante- and post-nuclear regions in the varicocele group were significantly more than those in the fertile group. In both fertile and varicocele groups, normal or abnormal nuclear-shaped spermatozoa with one or more vacuoles only located in the post-nuclear region occurred sparingly. The SNVA provides a useful additional approach to identify the status of NV in human spermatozoa for diagnostic purposes. A good sperm sample would have more spermatozoa without NV or with one small NV located in the ante-nuclear region. © 2014 Blackwell Verlag GmbH.

  2. Persistent photovoltage in methylammonium lead iodide perovskite solar cells

    Directory of Open Access Journals (Sweden)

    A. Baumann

    2014-08-01

    Full Text Available We herein perform open circuit voltage decay (OCVD measurements on methylammonium lead iodide (CH3NH3PbI3 perovskite solar cells to increase the understanding of the charge carrier recombination dynamics in this emerging technology. Optically pulsed OCVD measurements are conducted on CH3NH3PbI3 solar cells and compared to results from another type of thin-film photovoltaics, namely, the two reference polymer–fullerene bulk heterojunction solar cell devices based on P3HT:PC60BM and PTB7:PC70BM blends. We observe two very different time domains of the voltage transient in the perovskite solar cell with a first drop on a short time scale that is similar to the decay in the studied organic solar cells. However, 65%–70% of the maximum photovoltage persists on much longer timescales in the perovskite solar cell than in the organic devices. In addition, we find that the recombination dynamics in all time regimes are dependent on the starting illumination intensity, which is also not observed in the organic devices. We then discuss the potential origins of these unique behaviors.

  3. Chloride, bromide and iodide scintillators with europium doping

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2014-08-26

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

  4. Persistent photovoltage in methylammonium lead iodide perovskite solar cells

    Science.gov (United States)

    Baumann, A.; Tvingstedt, K.; Heiber, M. C.; Väth, S.; Momblona, C.; Bolink, H. J.; Dyakonov, V.

    2014-08-01

    We herein perform open circuit voltage decay (OCVD) measurements on methylammonium lead iodide (CH3NH3PbI3) perovskite solar cells to increase the understanding of the charge carrier recombination dynamics in this emerging technology. Optically pulsed OCVD measurements are conducted on CH3NH3PbI3 solar cells and compared to results from another type of thin-film photovoltaics, namely, the two reference polymer-fullerene bulk heterojunction solar cell devices based on P3HT:PC60BM and PTB7:PC70BM blends. We observe two very different time domains of the voltage transient in the perovskite solar cell with a first drop on a short time scale that is similar to the decay in the studied organic solar cells. However, 65%-70% of the maximum photovoltage persists on much longer timescales in the perovskite solar cell than in the organic devices. In addition, we find that the recombination dynamics in all time regimes are dependent on the starting illumination intensity, which is also not observed in the organic devices. We then discuss the potential origins of these unique behaviors.

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

    Science.gov (United States)

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

    2013-10-21

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

  6. Development of Optical Isolators for Visible Light Using Terbium Aluminum Garnet (Tb3Al5O12) Single Crystals

    Science.gov (United States)

    Geho, Mikio; Takagi, Takashi; Chiku, Shinichiro; Fujii, Takashi

    2005-07-01

    We have recently reported the successful growth of incongruently melting terbium aluminum garnet (Tb3Al5O12; TAG) single crystals by the hybrid laser FZ (floating zone) method. Optical property evaluations confirmed a high transmittance and a larger Verdet constant than conventional Tb3Ga5O12 (TGG) crystals and/or Faraday glasses. In this study, we attempted to design, fabricate, and evaluate optical isolators in visible light through near-infrared (NIR) regions using TAG crystals. A finite element method (FEM) simulation of possible models led us to the preferable one based on a radially magnetized magnet. To realize this, we employed a pseudo-radially magnetized magnet. The target wavelengths of the prototype device were 408, 808, and 1064 nm. The typical extinction ratio was more than 30 dB and the insertion loss was less than 0.3 dB for AR-coated devices.

  7. Permeation of iodide from iodine-enriched yeast through porcine intestine.

    Science.gov (United States)

    Ryszka, Florian; Dolińska, Barbara; Zieliński, Michał; Chyra, Dagmara; Dobrzański, Zbigniew

    2013-01-01

    Iodine deficiency is a common phenomenon, threatening the whole global human population. Recommended daily intake of iodine is 150 μg for adults and 250 μg for pregnant and breastfeeding women. About 50% of human population can be at risk of moderate iodine deficiency. Due to this fact, increased iodine supplementation is recommended, through intake of iodized mineral water and salt iodization. The aim of this study was to investigate permeation and absorption of iodide from iodine bioplex (experimental group) in comparison with potassium iodide (controls). Permeation and absorption processes were investigated in vitro using a porcine intestine. The experimental model was based on a standard Franz diffusion cell (FD-Cell). The iodine bioplex was produced using Saccharomyces cerevisiae yeast and whey powder: iodine content - 388 μg/g, total protein - 28.5%, total fat - 0.9%., glutamic acid - 41.2%, asparaginic acid - 29.4%, lysine - 24.8%; purchased from: F.Z.N.P. Biochefa, Sosnowiec, Poland. Potassium iodide was used as controls, at 388 μg iodine concentration, which was the same as in iodine-enriched yeast bioplex. A statistically significant increase in iodide permeation was observed for iodine-enriched yeast bioplex in comparison with controls - potassium iodide. After 5h the total amount of permeated iodide from iodine-enriched yeast bioplex was 85%, which is ~ 2-fold higher than controls - 37%. Iodide absorption was by contrast statistically significantly higher in controls - 7.3%, in comparison with 4.5% in experimental group with iodine-enriched yeast bioplex. Presented results show that iodide permeation process dominates over absorption in case of iodine-enriched yeast bioplex.

  8. Methodology for assaying iodide conductance in proteoliposomes: specific induction by thyroid membrane protein.

    OpenAIRE

    Golstein, P E; SENER, A.; Beauwens, R.

    1995-01-01

    A sensitive assay is developed to assess the existence of an iodide channel in a fraction of solubilized membrane proteins. This step is critical when considering various procedures for purification of this channel. Sodium cholate is used as a detergent as it does not denature the iodide channel. A simple and rapid method involving gel-filtration chromatography is used simultaneously to remove the detergent and to adjust the buffer composition, before protein insertion into liposomes. The pre...

  9. A Selective Iodide Ion Sensor Electrode Based on Functionalized ZnO Nanotubes

    Directory of Open Access Journals (Sweden)

    Magnus Willander

    2013-02-01

    Full Text Available In this research work, ZnO nanotubes were fabricated on a gold coated glass substrate through chemical etching by the aqueous chemical growth method. For the first time a nanostructure-based iodide ion selective electrode was developed. The ZnO nanotubes were functionalized with miconazole ion exchanger and the electromotive force (EMF was measured by the potentiometric method. The iodide ion sensor exhibited a linear response over a wide range of concentrations (1 × 10−6 to 1 × 10−1 M and excellent sensitivity of –62 ± 1 mV/decade. The detection limit of the proposed sensor was found to be 5 × 10−7 M. The effects of pH, temperature, additive, plasticizer and stabilizer on the potential response of iodide ion selective electrode were also studied. The proposed iodide ion sensor demonstrated a fast response time of less than 5 s and high selectivity against common organic and the inorganic anions. All the obtained results revealed that the iodide ion sensor based on functionalized ZnO nanotubes may be used for the detection of iodide ion in environmental water samples, pharmaceutical products and other real samples.

  10. A selective iodide ion sensor electrode based on functionalized ZnO nanotubes.

    Science.gov (United States)

    Ibupoto, Zafar Hussain; Khun, Kimleang; Willander, Magnus

    2013-02-04

    In this research work, ZnO nanotubes were fabricated on a gold coated glass substrate through chemical etching by the aqueous chemical growth method. For the first time a nanostructure-based iodide ion selective electrode was developed. The ZnO nanotubes were functionalized with miconazole ion exchanger and the electromotive force (EMF) was measured by the potentiometric method. The iodide ion sensor exhibited a linear response over a wide range of concentrations (1 × 10-6 to 1 × 10-1 M) and excellent sensitivity of -62 ± 1 mV/decade. The detection limit of the proposed sensor was found to be 5 × 10-7 M. The effects of pH, temperature, additive, plasticizer and stabilizer on the potential response of iodide ion selective electrode were also studied. The proposed iodide ion sensor demonstrated a fast response time of less than 5 s and high selectivity against common organic and the inorganic anions. All the obtained results revealed that the iodide ion sensor based on functionalized ZnO nanotubes may be used for the detection of iodide ion in environmental water samples, pharmaceutical products and other real samples.

  11. Modelling iodide – iodate speciation in atmospheric aerosol: Contributions of inorganic and organic iodine chemistry

    Directory of Open Access Journals (Sweden)

    S. Pechtl

    2007-01-01

    Full Text Available The speciation of iodine in atmospheric aerosol is currently poorly understood. Models predict negligible iodide concentrations but accumulation of iodate in aerosol, both of which is not confirmed by recent measurements. We present an updated aqueous phase iodine chemistry scheme for use in atmospheric chemistry models and discuss sensitivity studies with the marine boundary layer model MISTRA. These studies show that iodate can be reduced in acidic aerosol by inorganic reactions, i.e., iodate does not necessarily accumulate in particles. Furthermore, the transformation of particulate iodide to volatile iodine species likely has been overestimated in previous model studies due to negligence of collision-induced upper limits for the reaction rates. However, inorganic reaction cycles still do not seem to be sufficient to reproduce the observed range of iodide – iodate speciation in atmospheric aerosol. Therefore, we also investigate the effects of the recently suggested reaction of HOI with dissolved organic matter to produce iodide. If this reaction is fast enough to compete with the inorganic mechanism, it would not only directly lead to enhanced iodide concentrations but, indirectly via speed-up of the inorganic iodate reduction cycles, also to a decrease in iodate concentrations. Hence, according to our model studies, organic iodine chemistry, combined with inorganic reaction cycles, is able to reproduce observations. The presented chemistry cycles are highly dependent on pH and thus offer an explanation for the large observed variability of the iodide – iodate speciation in atmospheric aerosol.

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

    Science.gov (United States)

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

    2016-12-15

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

  13. A glucose bio-battery prototype based on a GDH/poly(methylene blue) bioanode and a graphite cathode with an iodide/tri-iodide redox couple.

    Science.gov (United States)

    Wang, Jen-Yuan; Nien, Po-Chin; Chen, Chien-Hsiao; Chen, Lin-Chi; Ho, Kuo-Chuan

    2012-07-01

    A glucose bio-battery prototype independent of oxygen is proposed based on a glucose dehydrogenase (GDH) bioanode and a graphite cathode with an iodide/tri-iodide redox couple. At the bioanode, a NADH electrocatalyst, poly(methylene blue) (PMB), which can be easily grown on the electrode (screen-printed carbon paste electrode, SPCE) by electrodeposition, is harnessed and engineered. We find that carboxylated multi-walled carbon nanotubes (MWCNTs) are capable of significantly increasing the deposition amount of PMB and thus enhancing the PMB's electrocatalysis of NADH oxidation and the glucose bio-battery's performance. The choice of the iodide/tri-iodide redox couple eliminates the dependence of oxygen for this bio-battery, thus enabling the bio-battery with a constant current-output feature similar to that of the solar cells. The present glucose bio-battery prototype can attain a maximum power density of 2.4 μW/cm(2) at 25 °C. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  14. Comparison of antimicrobial activity of sodium hypochlorite 2.5%, iodide potassium iodide 2%, and chlorhexidine 2% on the enterococcus faecalis after root canal filling

    Directory of Open Access Journals (Sweden)

    Fatemeh Mokhtari

    2015-12-01

    Full Text Available Background and Aims: Bacteria and their products have a major role in pulp and periapical diseases. The purpose of this study was to compare the antimicrobial activity of sodium hypochlorite, iodide potassium iodide and chlorhexidine on the enterococcus faecalis after root canal filling. Materials and Methods: In this experimental study, 95 single canal human teeth were collected. Then after washing and cleaning and filing, the sterilization done using an autoclave. The teeth were smeared with enterococcus faecalis except five which selected as controls and then divided them into 3 groups which A randomly represented the irrigation by sodium hypochlorite, iodide potassium iodide (IKI and chlorhexidine solution were done. The teeth were filled with gutta-percha and then incubated in a incubator for 90 days at a temperature of 37° C. The specimens were analyzed for Colony Count. Data were analyzed using Kruskal-Wallis test and Chi-Square. Results: According to the results of this study, the correlation between the 3 groups of cultured teeth were not significant (P=0.812.The specimens which were washed by IKI had the most positive amount of cultures (23.3% and the specimens which washed by chlorhexidine had the lowest (16.7%. Conclusion: The results of this study showed that after the use of different wash solutions, no statistically significant difference exist in their antimicrobial activity after root canal therapy.

  15. THERAPY OF GRAVES’ DISEASE WITH SODIUM IODIDE-131

    Directory of Open Access Journals (Sweden)

    I Wayan Hartadi Noor

    2013-11-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Graves’ disease is the most common form of thyrotoxicosis, with a peak incidence in the 20-40 year of age group. Females are involved about five times more commonly than male. The easiest sign to recognize patients with Graves’ disease is the present of Graves’ ophthalmopathy. The diagnosis of Graves’ disease may sometimes base only on a physical examination and a medical history. Diffuse thyroid enlargement and sign of thyrotoxicosis, mainly ophthalmopathy and to lesser extent dermopathy, usually adequate for diagnosis. TSH test combined with FT4 test is usually the first laboratory test performs in these patients. The patients suffered Graves’ disease can be treated with antithyroid drug therapy or undergo subtotal Thyroidectomy. Another therapy is by using sodium iodide-131, where this therapy has advantages including easy administration, effectiveness, low expense, and absence of pain. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  16. Investigation of the luminescent properties of terbium-anthranilate complexes and application to the determination of anthranilic acid derivatives in aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Arnaud, N.; Georges, J

    2003-01-10

    The luminescent properties of terbium complexes with furosemide (FR), flufenamic (FF) acid, tolfenamic (TF) acid and mefenamic (MF) acid have been investigated in aqueous solutions. For all four compounds, complexation occurs when the carboxylic acid of the aminobenzoic group is dissociated and is greatly favoured in the presence of trioctylphosphine oxide as co-ligand and Triton X-100 as surfactant. Under optimum conditions, luminescence of the lanthanide ion is efficiently sensitised and the lifetime of the {sup 5}D{sub 4} resonance level of terbium in the complex is ranging between 1 and 1.9 ms, against 0.4 ms for the aqua ion. The sensitivity of the method for the determination of anthranilic acid derivatives is improved by one to two orders of magnitude with respect to that achieved using native fluorescence or terbium-sensitised luminescence in methanol. The limits of detection are 2x10{sup -10}, 5x10{sup -10} and 2x10{sup -9} mol l{sup -1} for flufenamic acid, furosemide and tolfenamic acid, and mefenamic acid, respectively, with within-run RSD values of less than 1%. The method has been applied to the determination of flufenamic acid in spiked calf sera with and without sample pretreatment. Depending on the method and the analyte concentration, the recovery was ranging between 83 and 113% and the lowest concentration attainable in serum samples was close to 1x10{sup -7} mol l{sup -1}.

  17. Carbamazepine (Tegretol) inhibits in vivo iodide uptake and hormone synthesis in rat thyroid glands

    Energy Technology Data Exchange (ETDEWEB)

    Villa, S.M.; Alexander, N.M.

    1987-01-01

    Decreased serum concentrations of T3 and T4 occur in patients treated with the anticonvulsant drug carbamazepine (CBZ), but with rare exception, these patients remain euthyroid. The mechanism that accounts for diminished hormone levels is unknown, and our objective was to study the direct effect of CBZ on iodide uptake and hormone synthesis in thyroid glands of CBZ-treated and pair-fed control rats. Chronic ingestion (per os) of CBZ in male rats reduced the four hour thyroid 131I-iodide uptake by approximately 60%. This inhibition occurred after the animals had received sufficient CBZ to attain plasma CBZ concentrations of 0.8 microgram/ml. Continued treatment with CBZ ranging from 560 to 800 mg/kg/day for 14 days did not result in further inhibition of iodide uptake even though the plasma CBZ concentrations had increased 6-20 fold. No inhibition of iodide uptake was apparent when the animals initially received CBZ ranging from 40 to 152 mg/kg body weight for 22 days when there were no detectable levels of plasma CBZ. Overall growth rates of CBZ-treated rats were slightly (6-10%) less than the pair-fed control animals. Plasma T4 concentrations were reduced by 18% (p less than 0.05) in the CBZ-fed animals, while T3 concentrations were diminished by 53% (p less than 0.01). CBZ appeared to alter thyroidal iodide transport because the thyroid:plasma iodide ratios were decreased by 26% in the drug-treated rats. The distribution of radioiodine in thyroidal iodoamino acids was essentially the same in both groups of rats but the absolute quantities of radioiodine were more than 2.5 times greater in the control rats. CBZ failed to inhibit peroxidase-catalyzed iodide and guaiacol oxidation in vitro.

  18. Influence of iodide and iodolactones on thyroid apoptosis. Evidence that apoptosis induced by iodide is mediated by iodolactones in intact porcine thyroid follicles.

    Science.gov (United States)

    Langer, R; Burzler, C; Bechtner, G; Gärtner, R

    2003-09-01

    Iodine induced thyroid involution is caused by apoptosis rather than necrosis. This effect of iodide on apoptosis of thyroid epithelial cells may be not a direct one but mediated by iodinated derivatives i.e. of polyunsaturated fatty acids, especially of iodolactones, which have previously shown to inhibit thyroid cell proliferation. We studied the influence on apoptosis of iodide (2 microM and 20 microM) and iodolactone (0.05 microM and 0.5 microM), with and without TSH (1 mU/ml), using a well characterized ex vivo- culture system of intact porcine thyroid follicles in three-dimensional culture. Apoptosis and necrosis was evaluated by electron-microscopy. Stimulation with 2 and 20 microM iodide rapidly induced a rate of apoptosis (4 - 6 %) comparable to about 40-fold lower doses of delta-iodolactone (0.05 microM and 0.5 microM). Addition of TSH (1 mU/ml) caused a slight but not significant further increase of the incidence of apoptotic cells. The rate of necrotic thyroid epithelial cells (1 - 2 %) was similar in all experiments. As delta-iodolactone in very low concentrations--comparable to iodide in higher concentrations--not only inhibits growth but also induces apoptosis, it has to be supposed that the effect of iodide is mediated by this iodinated compound. However, further experiments are necessary to confirm this hypothesis. In addition it could be demonstrated, that apoptosis is a very rapid and limited process in intact follicles. This also may explain, why iodine supplementation even in high doses does not lead to thyroid atrophy but only normalisation of thyroid size. These results confirm that apoptosis is an important regulated and limited mechanism in goiter involution.

  19. Processes of adsorption/desorption of iodides and cadmium cations onto/from Ag(111

    Directory of Open Access Journals (Sweden)

    VLADIMIR D. JOVIĆ

    2011-02-01

    Full Text Available In this work, the adsorption/desorption processes of iodides and cadmium cations in the presence of iodides onto/from Ag(111 were investigated. It was shown that both processes were complex, characterized by several peaks on the cyclic voltammograms (CVs. By PeakFit analysis of the recorded CVs and subsequent fitting of the obtained peaks by the Frumkin adsorption isotherm, the interaction parameter (f and the Gibbs energy of adsorption (DGads for each adsorbed phase were determined. In the case of iodide adsorption, four peaks were characterized by negative values of f, indicating attractive lateral interaction between the adsorbed anions, while two of them possessed value of f < –4, indicating phase transition processes. The adsorption/desorption processes of cadmium cations (underpotential deposition – UPD of cadmium in the presence of iodide anions was characterized by two main peaks, each of them being composed of two or three peaks with negative values of f. By the analysis of charge vs. potential dependences obtained either from the CVs or current transients on potentiostatic pulses, it was concluded that adsorbed iodides did not undergo desorption during the process of Cd UPD, but became replaced by Cd ad-atoms and remained adsorbed on top of a Cd layer and/or in between Cd the ad-atoms.

  20. Capture of organic iodides from nuclear waste by metal-organic framework-based molecular traps.

    Science.gov (United States)

    Li, Baiyan; Dong, Xinglong; Wang, Hao; Ma, Dingxuan; Tan, Kui; Jensen, Stephanie; Deibert, Benjamin J; Butler, Joseph; Cure, Jeremy; Shi, Zhan; Thonhauser, Timo; Chabal, Yves J; Han, Yu; Li, Jing

    2017-09-07

    Effective capture of radioactive organic iodides from nuclear waste remains a significant challenge due to the drawbacks of current adsorbents such as low uptake capacity, high cost, and non-recyclability. We report here a general approach to overcome this challenge by creating radioactive organic iodide molecular traps through functionalization of metal-organic framework materials with tertiary amine-binding sites. The molecular trap exhibits a high CH 3 I saturation uptake capacity of 71 wt% at 150 °C, which is more than 340% higher than the industrial adsorbent Ag 0 @MOR under identical conditions. These functionalized metal-organic frameworks also serve as good adsorbents at low temperatures. Furthermore, the resulting adsorbent can be recycled multiple times without loss of capacity, making recyclability a reality. In combination with its chemical and thermal stability, high capture efficiency and low cost, the adsorbent demonstrates promise for industrial radioactive organic iodides capture from nuclear waste. The capture mechanism was investigated by experimental and theoretical methods.Capturing radioactive organic iodides from nuclear waste is important for safe nuclear energy usage, but remains a significant challenge. Here, Li and co-workers fabricate a stable metal-organic framework functionalized with tertiary amine groups that exhibits high capacities for radioactive organic iodides uptake.

  1. Trapping radiodine, in the form of methyl iodide, on nuclear carbon

    Energy Technology Data Exchange (ETDEWEB)

    Nacapricha, D. [Mahidol Univ., Bangkok (Thailand); Taylor, C. [John Moores Univ., Liverpool (United Kingdom)

    1996-12-31

    Studies have been performed on potassium-iodide-impregnated charcoals of the type used in the nuclear industry for trapping radioiodine released during nuclear fission. The effects of various parameters on the trapping efficiency of methyl iodide have been investigated. A variation in particle size within a bulk charcoal caused poor precision in K value measurements because of differences in surface area, pore volume, and bed density, leading to differences in the deposition of the impregnant. Precision is improved by sieving the charcoal to a narrower size because smaller particles have a higher porosity. This finding is supported by surface area and pore measurements. Two methods of impregnation are compared by measuring K values and the deposition of potassium iodide. Charcoal impregnated by rotary evaporation exhibits both higher K values and higher potassium iodide contents than sprayed charcoal. Two designs of spraying drum are compared: a drum with helical vanes allows more efficient deposition and more uniform distribution of impregnant than a drum with axial vanes. A decrease in the K value with increasing humidity correlates with the available surface area. A similar correlation exists between water content and available pore volume. Aging of potassium-iodide-impregnated charcoal, caused by the formation of oxygen complexes on the surface, is associated with significant falls in K value. K values of charcoals also can be restored to at least their original values by heat treatment in the absence of air. 12 refs., 6 figs., 1 tab.

  2. A Combined Experimental and Molecular Dynamics Study of Iodide-Based Ionic Liquid and Water Mixtures.

    Science.gov (United States)

    Nickerson, Stella D; Nofen, Elizabeth M; Chen, Haobo; Ngan, Miranda; Shindel, Benjamin; Yu, Hongyu; Dai, Lenore L

    2015-07-16

    Iodide-based ionic liquids have been widely employed as iodide sources in electrolytes for applications utilizing the triiodide/iodide redox couple. While adding a low-viscosity solvent such as water to ionic liquids can greatly enhance their usefulness, mixtures of highly viscous iodide-containing ILs with water have never been studied. This paper investigates, for the first time, mixtures of water and the ionic liquid 1-butyl-3-methylimidazolium iodide ([BMIM][I]) through a combined experimental and molecular dynamics study. The density, melting point, viscosity, and conductivity of these mixtures were measured by experiment. The composition region below 50% water by mole was found to differ dramatically from the region above 50% water, with trends in density and melting point differing before and after that point. Water was found to have a profound effect on viscosity and conductivity of the IL, and the effect of hydrogen bonding was discussed. Molecular dynamics simulations representing the same mixture compositions were performed. Molecular ordering was observed, as were changes in this ordering corresponding to water content. Molecular ordering was related to the experimentally measured mixture properties, providing a possible explanation for the two distinct composition regions identified by experiment.

  3. Capture of organic iodides from nuclear waste by metal-organic framework-based molecular traps

    KAUST Repository

    Li, Baiyan

    2017-09-01

    Effective capture of radioactive organic iodides from nuclear waste remains a significant challenge due to the drawbacks of current adsorbents such as low uptake capacity, high cost, and non-recyclability. We report here a general approach to overcome this challenge by creating radioactive organic iodide molecular traps through functionalization of metal-organic framework materials with tertiary amine-binding sites. The molecular trap exhibits a high CH3I saturation uptake capacity of 71 wt% at 150 °C, which is more than 340% higher than the industrial adsorbent Ag0@MOR under identical conditions. These functionalized metal-organic frameworks also serve as good adsorbents at low temperatures. Furthermore, the resulting adsorbent can be recycled multiple times without loss of capacity, making recyclability a reality. In combination with its chemical and thermal stability, high capture efficiency and low cost, the adsorbent demonstrates promise for industrial radioactive organic iodides capture from nuclear waste. The capture mechanism was investigated by experimental and theoretical methods.Capturing radioactive organic iodides from nuclear waste is important for safe nuclear energy usage, but remains a significant challenge. Here, Li and co-workers fabricate a stable metal-organic framework functionalized with tertiary amine groups that exhibits high capacities for radioactive organic iodides uptake.

  4. Silver (I-coordinated bis(trimethoxysilylpropylamine Polycondensate for Adsorptive Removal of Iodide from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Zhang Huifang

    2016-01-01

    Full Text Available Silver-coordinated bis(trimethoxysilylpropylamine polycondensate (TSPA-AgNO3 was prepared and used to adsorb iodide ions in aqueous solutions. Batch adsorption studies were performed to investigate the effects of pH, temperature and coexisting NaCl on adsorption behavior. The results show that TSPA-AgNO3 is easy to prepare and remarkably efficient in adsorbing iodide in water, especially in acidic solutions. Furthermore, increased temperature accelerated the adsorption, while coexisting NaCl inhibited the adsorption. TSPA-AgNO3 also proved to be chemically stable in simulated environmental situations, which reveals a promising potential for applying this method to the disposal of radioactive iodide in environment water.

  5. Polymer electrolytes from PEO and novel quaternary ammonium iodides for dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Kang, J.; Li, W.; Wang, X.; Lin, Y.; Xiao, X.; Fang, S. [Chinese Academy of Sciences, Beijing (China). Institute of Chemistry

    2003-07-15

    Polymer electrolytes were prepared by blending high molecular weight poly(ethylene oxide) (PEO) and a series of novel quaternary ammonium iodides, the polysiloxanes with oligo (oxyethylene) side chains and quaternary ammonium groups. X-ray diffraction (XRD) measurements ensured relatively low crystallinity when the quaternary ammonium iodides were incorporated into the PEO host. The ionic conductivity of these complexes was improved with the addition of plasticizers. The improvement in the ionic conductivity was determined by the polarity, viscosity and amounts of plasticizers. A plasticized electrolyte containing the novel quaternary ammonium iodide was successfully used in fabricating a quasi-solid-state dye-sensitized solar cell for first time. The fill factor and energy conversion efficiency of the cell were calculated to be 0.68 and 1.39%, respectively. (author)

  6. Simultaneous detection of iodine and iodide on boron doped diamond electrodes.

    Science.gov (United States)

    Fierro, Stéphane; Comninellis, Christos; Einaga, Yasuaki

    2013-01-15

    Individual and simultaneous electrochemical detection of iodide and iodine has been performed via cyclic voltammetry on boron doped diamond (BDD) electrodes in a 1M NaClO(4) (pH 8) solution, representative of typical environmental water conditions. It is feasible to compute accurate calibration curve for both compounds using cyclic voltammetry measurements by determining the peak current intensities as a function of the concentration. A lower detection limit of about 20 μM was obtained for iodide and 10 μM for iodine. Based on the comparison between the peak current intensities reported during the oxidation of KI, it is probable that iodide (I(-)) is first oxidized in a single step to yield iodine (I(2)). The latter is further oxidized to obtain IO(3)(-). This technique, however, did not allow for a reasonably accurate detection of iodate (IO(3)(-)) on a BDD electrode. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Efficient photoreductive decomposition of N-nitrosodimethylamine by UV/iodide process

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Zhuyu; Zhang, Chaojie, E-mail: myrazh@tongji.edu.cn; Zhao, Xiaoyun; Chen, Jing; Zhou, Qi

    2017-05-05

    Highlights: • N-nitrosodimethylamine (NDMA) was effectively decomposed by UV/iodide process. • NDMA was completely converted to nontoxic end products by UV/iodide process. • The photoreductive process was mainly attributed to the attack of hydrated electrons on the photoexcited NDMA. • The elimination of toxic intermediates was greatly enhanced as pH increased, but its effect on NDMA removal was negligible. - Abstract: N-nitrosodimethylamine (NDMA) has aroused extensive concern as a disinfection byproduct due to its high toxicity and elevated concentration levels in water sources. This study investigates the photoreductive decomposition of NDMA by UV/iodide process. The results showed that this process is an effective strategy for the treatment of NDMA with 99.2% NDMA removed within 10 min. The depletion of NDMA by UV/iodide process obeyed pseudo-first-order kinetics with a rate constant (k{sub 1}) of 0.60 ± 0.03 min{sup −1}. Hydrated electrons (e{sub aq}{sup −}) generated by the UV irradiation of iodide were proven to play a critical role. Dimethylamine (DMA) and nitrite (NO{sub 2}{sup −}) were formed as the main intermediate products, which completely converted to formate (HCOO{sup −}), ammonium (NH{sub 4}{sup +}) and nitrogen (N{sub 2}). Therefore, not only the high efficiencies in NDMA destruction, but the elimination of toxic intermediates make UV/iodide process advantageous. A photoreduction mechanism was proposed: NDMA initially absorbed photons to a photoexcited state, and underwent a cleavage of N−NO bond under the attack of e{sub aq}{sup −}. The solution pH had little impact on NDMA removal. However, alkaline conditions were more favorable for the elimination of DMA and NO{sub 2}{sup −}, thus effectively reducing the secondary pollution.

  8. Chlorine-free pyrotechnics: copper(I) iodide as a "green" blue-light emitter.

    Science.gov (United States)

    Klapötke, Thomas M; Rusan, Magdalena; Sabatini, Jesse J

    2014-09-01

    The generation of blue-light-emitting pyrotechnic formulations without the use of chlorine-containing compounds is reported. Suitable blue-light emission has been achieved through the generation of molecular emitting copper(I) iodide. The most optimal copper(I) iodide based blue-light-emitting formulation was found to have performances exceeding those of chlorine-containing compositions, and was found to be insensitive to various ignition stimuli. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. [The genetic action of ammonium molybdate and cadmium chloride and iodide].

    Science.gov (United States)

    Chopikashvili, L V; Bobyleva, L A; Shapiro, A N

    1991-01-01

    Ammonium molybdate cadmium iodide and cadmium chloride have been studied in test for their genotoxic effect on induction of DNA-cellular bonding, extrasynthesis of DNA in spermatozoa of mice as well as in test to estimate a fertility criterion of Drosophila males. Ammonium molybdate, cadmium iodide and cadmium chloride are stated to be able to induce injuries of native DNA in test on induction of DNA-cellular bonding and DNA-sex cells of mice and Drosophila melanogaster in dominant-lethal test and in experiments on estimation of a fertility coefficient of Drosophila males, respectively.

  10. Samarium(II) iodide-mediated intramolecular conjugate additions of alpha,beta-unsaturated lactones.

    Science.gov (United States)

    Molander, Gary A; St Jean, David J

    2002-05-31

    Samarium(II) iodide, in the presence of catalytic amounts of nickel(II) iodide, has been used to promote intramolecular conjugate additions of alkyl halides onto alpha,beta-unsaturated lactones. This process has been shown to be applicable to a number of alpha,beta-unsaturated lactones, including tetrasubstituted olefins, and has been demonstrated to be quite general for the formation of saturated bicyclic and tricyclic lactones. The method presented herein provides a mild, efficient process to form structurally complex lactones from simple precursors.

  11. Tris(1,2-dimethoxyethane-κ2O,O′iodidocalcium iodide

    Directory of Open Access Journals (Sweden)

    Siou-Wei Ou

    2012-02-01

    Full Text Available In the title complex, [CaI(C4H10O23]I, the CaII atom is seven-coordinated by six O atoms from three 1,2-dimethoxyethane (DME ligands and one iodide anion in a distorted pentagonal–bipyramidal geometry. The I atom and one of the O atoms from a DME ligand lie in the axial positions while the other O atoms lie in the basal plane. The other iodide anion is outside the complex cation.

  12. Studying Equilibrium in the Chemical Reaction between Ferric and Iodide Ions in Solution Using a Simple and Inexpensive Approach

    Science.gov (United States)

    Nikolaychuk, Pavel Anatolyevich; Kuvaeva, Alyona Olegovna

    2016-01-01

    A laboratory experiment on the study of the chemical equilibrium based on the reaction between ferric and iodide ions in solution with the formation of ferrous ions, free iodine, and triiodide ions is developed. The total concentration of iodide and triiodide ions in the reaction mixture during the reaction is determined by the argentometric…

  13. The BLI-3/TSP-15/DOXA-1 dual oxidase complex is required for iodide toxicity in Caenorhabditis elegans.

    Science.gov (United States)

    Xu, Zhaofa; Luo, Jintao; Li, Yu; Ma, Long

    2014-12-04

    Iodine is an essential trace element for life. Iodide deficiency can lead to defective biosynthesis of thyroid hormones and is a major cause of hypothyroidism and mental retardation. Excess iodide intake, however, has been linked to different thyroidal diseases. How excess iodide causes harmful effects is not well understood. Here, we found that the nematode Caenorhabditis elegans exhibits developmental arrest and other pleiotropic defects when exposed to excess iodide. To identify the responsible genes, we performed a forward genetic screen and isolated 12 mutants that can survive in excess iodide. These mutants define at least four genes, two of which we identified as bli-3 and tsp-15. bli-3 encodes the C. elegans ortholog of the mammalian dual oxidase DUOX1 and tsp-15 encodes the tetraspanin protein TSP-15, which was previously shown to interact with BLI-3. The C. elegans dual oxidase maturation factor DOXA-1 is also required for the arresting effect of excess iodide. Finally, we detected a dramatically increased biogenesis of reactive oxygen species in animals treated with excess iodide, and this effect can be partially suppressed by bli-3 and tsp-15 mutations. We propose that the BLI-3/TSP-15/DOXA-1 dual oxidase complex is required for the toxic pleiotropic effects of excess iodide. Copyright © 2015 Xu et al.

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-12-15

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

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

    Directory of Open Access Journals (Sweden)

    Niko Hildebrandt

    2011-10-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-12-16

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

  18. Optical properties and electrical transport of thin films of terbium(III bis(phthalocyanine on cobalt

    Directory of Open Access Journals (Sweden)

    Peter Robaschik

    2014-11-01

    Full Text Available The optical and electrical properties of terbium(III bis(phthalocyanine (TbPc2 films on cobalt substrates were studied using variable angle spectroscopic ellipsometry (VASE and current sensing atomic force microscopy (cs-AFM. Thin films of TbPc2 with a thickness between 18 nm and 87 nm were prepared by organic molecular beam deposition onto a cobalt layer grown by electron beam evaporation. The molecular orientation of the molecules on the metallic film was estimated from the analysis of the spectroscopic ellipsometry data. A detailed analysis of the AFM topography shows that the TbPc2 films consist of islands which increase in size with the thickness of the organic film. Furthermore, the cs-AFM technique allows local variations of the organic film topography to be correlated with electrical transport properties. Local current mapping as well as local I–V spectroscopy shows that despite the granular structure of the films, the electrical transport is uniform through the organic films on the microscale. The AFM-based electrical measurements allow the local charge carrier mobility of the TbPc2 thin films to be quantified with nanoscale resolution.

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

    Science.gov (United States)

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

    2015-09-21

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

  20. Micelle enhanced and terbium sensitized spectrofluorimetric determination of danofloxacin in milk using molecularly imprinted solid phase extraction

    Science.gov (United States)

    Kaur, Kuldeep; Saini, Shivender Singh; Malik, Ashok Kumar; Singh, Baldev

    2012-10-01

    An efficient molecularly imprinted solid phase extraction (MISPE)-spectrofluorimetric method was developed to sensitively determine danofloxacin (DAN) in milk samples. Solid phase extraction procedure using MISPE cartridges was first performed on milk samples and then spectrofluorimetric determination was done at 546 nm using an excitation wavelength of 285 nm in presence of terbium and sodium dodecyl benzene sulfonate (SDBS). It was found that SDBS significantly enhanced the fluorescence intensity of the DAN-Tb3+ complex. Various factors affecting the fluorescence intensity of DAN-Tb3+-SDBS system were studied and conditions were optimized. The enhanced fluorescence intensity of the system (ΔF) showed a good linear relationship with the concentration of DAN over the range of 8.4 × 10-9-3.4 × 10-7 mol L-1 with a correlation coefficient of 0.9996. The detection limit was determined as 2.0 × 10-9 mol L-1 and the limit of quantification was determined as 6.5 × 10-9 mol L-1. The MISPE-spectrofluorimetric procedure was successfully applied to the determination of DAN in milk samples. The method is simple, rapid, sensitive and allows interference free determination of DAN in complex fluorescent matrices like milk. The method can be used to determine whether the DAN residues in milk exceed MRLs or not.

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

    Energy Technology Data Exchange (ETDEWEB)

    Paganini, Paula P.; Felinto, Maria Claudia F.C.; Kodaira, Claudia A., E-mail: paulapaganini@usp.b, E-mail: mfelinto@ipen.b, E-mail: claudiakodaira@yahoo.co [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Brito, Hermi F., E-mail: hefbrito@iq.usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Quimica. Lab. de Elementos do Bloco f; Nunes, Luiz Antonio O., E-mail: luizant@ifsc.usp.b [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Inst. de Fisica. Dept. de Fisica e Informatica

    2009-07-01

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

  2. Analysis of iodide and iodate in Lake Mead, Nevada using a headspace derivatization gas chromatography-mass spectrometry.

    Science.gov (United States)

    Dorman, James W; Steinberg, Spencer M

    2010-02-01

    We report here a derivatization headspace method for the analysis of inorganic iodine in water. Samples from Lake Mead, the Las Vegas Wash, and from Las Vegas tap water were examined. Lake Mead and the Las Vegas Wash contained a mixture of both iodide and iodate. The average concentration of total inorganic iodine (TII) for Lake Mead was approximately 90 nM with an iodide-to-iodate ratio of approximately 1. The TII concentration (approximately 160 nM) and the ratio of iodide to iodate were higher for the Las Vegas Wash (approximately 2). The TII concentration for tap water was close to that of Lake Mead (approximately 90 nM); however, tap water contained no detectable iodide as a result of ozonation and chlorine treatment which converts all of the iodide to iodate.

  3. Electrical double layer on silver iodide and overcharging in the presence of hydrolyzable cations

    NARCIS (Netherlands)

    Lyklema, J.; Golub, T.P.

    2007-01-01

    Previous studies on the surface charge and electrokinetic charge on silver iodide as a function of the pAg in the presence of some monovalent and trivalent cations as the counterions were extended to include the influence of pH. The main reason for this study was to investigate the possible

  4. Calibration and Performance Testing of Sodium Iodide, NaI (Tl ...

    African Journals Online (AJOL)

    The performance testing of a newly acquired sodium iodide detector (NaI), (Tl)) at Ghana Atomic Energy Commission (GAEC) was investigated by carrying out energy and efficiency calibration on the detector, as well as validation of its calibration. The energy and efficiency calibrations were performed using mixed ...

  5. The Reaction between Iron(II) Iodide and Potassium Dichromate(VI) in Acidified Aqueous Solution

    Science.gov (United States)

    Talbot, Christopher

    2013-01-01

    This "Science note" teaching lesson explores the possible reaction between the ions in a reaction mixture consisting of iron(II) iodide and potassium dichromate(VI) in acidified aqueous solution. The electrode potentials will be used to deduce any spontaneous reactions under standard thermodynamic conditions (298 K, 1 bar (approximately…

  6. Vapour-Deposited Cesium Lead Iodide Perovskites : Microsecond Charge Carrier Lifetimes and Enhanced Photovoltaic Performance

    NARCIS (Netherlands)

    Hutter, E.M.; Sutton, Rebecca J.; Chandrashekar, Sanjana; Abdi-Jalebi, Mojtaba; Stranks, Samuel D.; Snaith, Henry J.; Savenije, T.J.

    2017-01-01

    Metal halide perovskites such as methylammonium lead iodide (MAPbI3) are highly promising materials for photovoltaics. However, the relationship between the organic nature of the cation and the optoelectronic quality remains debated. In this work, we investigate the optoelectronic properties of

  7. Distribution of bromine in mixed iodide-bromide organolead perovskites and its impact on photovoltaic performance

    NARCIS (Netherlands)

    Zhou, Yang; Wang, Feng; Fang, Hong-Hua; Loi, Maria Antonietta; Xie, Fang-Yan; Zhao, Ni; Wong, Ching-Ping

    2016-01-01

    Mixed iodide-bromide (I-Br) organolead perovskites are of great interest for both single junction and tandem solar cells since the optical bandgap of the materials can be tuned by varying the bromine to iodine ratio. Yet, it remains unclear how bromine incorporation modifies the properties of the

  8. Regioselective conversion of primary alcohols into iodides in unprotected methyl furanosides and pyranosides

    DEFF Research Database (Denmark)

    Skaanderup, Philip Robert; Poulsen, Carina Storm; Hyldtoft, Lene

    2002-01-01

    Two methods are described for the regioselective displacement of the primary hydroxy group in methyl glycosides with iodide. The first method is a modification of a literature procedure employing triphenylphosphine and iodine, where purification has been carried out on a reverse phase column...

  9. Relaxation of the silver/silver iodide electrode in aqueous solution

    NARCIS (Netherlands)

    Peverelli, K.J.

    1979-01-01

    The aim of this study is to detect and characterize relaxation processes on silver/silver iodide electrodes in aqueous electrolyte solution. The information obtained is to be used for an estimation of the consequences of similar processes on colloidal AgI

  10. Photoexcitation dynamics in solution-processed formamidinium lead iodide perovskite thin films for solar cell applications

    NARCIS (Netherlands)

    Fang, Hong-Hua; Wang, Feng; Adjokatse, Sampson; Zhao, Ni; Even, Jacky; Loi, Maria Antonietta

    Formamidinium lead iodide (FAPbI(3)) is a newly developed hybrid perovskite that potentially can be used in high-efficiency solution-processed solar cells. Here, the temperature-dependent dynamic optical properties of three types of FAPbI(3) perovskite films (fabricated using three different

  11. Effect of Excess Iodide Intake on Salivary Glands in a Swiss Albino Mice Model

    Directory of Open Access Journals (Sweden)

    Gloria Romina Ross

    2017-01-01

    Full Text Available Iodine is an important micronutrient required for nutrition. Excess iodine has adverse effects on thyroid, but there is not enough information regarding its effect on salivary glands. In addition to food and iodized salt, skin disinfectants and maternal nutritional supplements contain iodide, so its intake could be excessive during pregnancy, lactation, and infancy. The aim of this work was to evaluate the effect of excess iodide ingestion on salivary glands during mating, gestation, lactation, and postweaning period in mouse. During assay, mice were allocated into groups: control and treatment groups (received distilled water with NaI 1 mg/mL. Water intake, glandular weight, and histology were analyzed. Treatment groups showed an increase in glandular weight and a significantly (p < 0.05 higher water intake than control groups. Lymphocyte infiltration was observed in animals of treatment groups, while there was no infiltration in glandular sections of control groups. Results demonstrated that a negative relationship could exist between iodide excess and salivary glands. This work is novel evidence that high levels of iodide intake could induce mononuclear infiltration in salivary glands. These results should be considered, especially in pregnant/lactating women, to whom a higher iodine intake is usually recommended.

  12. Electrokinetic properties and conductance relaxation of polystyrene and silver iodide plugs

    NARCIS (Netherlands)

    Hoven, van den J.J.

    1984-01-01

    This thesis describes an experimental study on the electrokinetic and electrical properties of concentrated polystyrene and silver iodide dispersions. The purpose of the study is to obtain information on the structure of the electrical double layer at the solid-liquid interface. Special

  13. Iodide Residues in Milk Vary between Iodine-Based Teat Disinfectants

    NARCIS (Netherlands)

    French, Elizabeth A; Mukai, Motoko; Zurakowski, Michael; Rauch, Bradley; Gioia, Gloria; Hillebrandt, Joseph R; Henderson, Mark; Schukken, Ynte H; Hemling, Thomas C

    Majority of iodine found in dairy milk comes from the diet and teat disinfection products used during milking process. The objective of this study was to evaluate the effects of 4 iodine-based teat dips on milk iodide concentrations varying in iodine level (0.25% vs. 0.5%, w/w), normal low viscosity

  14. Growth and properties of lead iodide thin films by spin coating

    Indian Academy of Sciences (India)

    solar cell [5], one of the highest solution-processed solar cells reported so far. Lead iodide exists in hexagonal crystalline structure having an intrinsic bandgap of .... According to spin coating theory [12], during spinning due to the centrifugal force most of the PbI2 solution is ejected from the substrate leaving a thin liquid film ...

  15. Real-Time Observation of Organic Cation Reorientation in Methylammonium Lead Iodide Perovskites

    NARCIS (Netherlands)

    Bakulin, Artem A.; Selig, Oleg; Bakker, Huib J.; Rezus, Yves L. A.; Mueller, Christian; Glaser, Tobias; Lovrincic, Robert; Sun, Zhenhua; Chen, Zhuoying; Walsh, Aron; Frost, Jarvist M.; Jansen, Thomas L. C.

    2015-01-01

    The introduction of a mobile and polarized organic moiety as a cation in 3D lead-iodide perovskites brings fascinating optoelectronic properties to these materials. The extent and the time scales of the orientational mobility of the organic cation and the molecular mechanism behind its motion remain

  16. The sodium iodide symporter (NIS) and potential regulators in normal, benign and malignant human breast tissue.

    LENUS (Irish Health Repository)

    Ryan, James

    2011-01-01

    The presence, relevance and regulation of the Sodium Iodide Symporter (NIS) in human mammary tissue remains poorly understood. This study aimed to quantify relative expression of NIS and putative regulators in human breast tissue, with relationships observed further investigated in vitro.

  17. A portable multi-syringe flow system for spectrofluorimetric determination of iodide in seawater.

    Science.gov (United States)

    Frizzarin, Rejane M; Aguado, Enrique; Portugal, Lindomar A; Moreno, Daniel; Estela, José M; Rocha, Fábio R P; Cerdà, Victor

    2015-11-01

    A miniaturized analyzer encompassing a poly(methyl methacrylate) chip with integrated spectrofluorimetric detection and solutions propelling by a multi-syringe module is proposed. Iodide was determined through its catalytic effect on the reaction between Ce(IV) and As(III). Matrix isopotential synchronous fluorescence was explored to set the excitation and emission wavelengths. A two-level full factorial design allowed to evaluate the significance of variables (Ce(IV), As(III) and H2SO4 concentrations) and their interaction effects in the experimental domain. A Doehlert Matrix was applied to identify the critical values. The optimized procedure showed a linear response from 1 to 100 μg L(-1) (S=53.7+2.61C, in which S is the net fluorescence and C is iodide concentration in μg L(-1)). Detection limit, coefficient of variation (n=6) and sampling rate were estimated at 0.3 μg L(-1), 0.8% and 20 h(-1), respectively. Recoveries within 90-117% were estimated for iodide spiked to seawater samples. The proposed procedure stands out because of the portability, robustness, and simplicity for in-field analysis of iodide in seawater. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Extension of HPM Pulse Duration by Cesium Iodide Cathodes in Crossed Field Devices

    National Research Council Canada - National Science Library

    Benford, James

    1998-01-01

    .... The introduction of cathodes made from Cesium Iodide-coated (CsI) carbon fiber has shown plasma speeds reduced by factors of a few from uncoated carbon fiber, but previous work was at low diode fields of a few 10's of kV/cm...

  19. Experimental study on iodine chemistry (EXSI) - Containment experiments with methyl iodide

    Energy Technology Data Exchange (ETDEWEB)

    Holm, J.; Ekberg, C. (Chalmers Univ. of Technology, Goeteborg (Sweden)); Kaerkelae, T.; Auvinen, A. (VTT, Espoo (Finland)); Glaenneskog, H. (Vattenfall Power Consultant, Goeteborg (Sweden))

    2011-05-15

    An experimental study on radiolytic decomposition of methyl iodide was conducted in co-operation between VTT and Chalmers University of Technology as a part of the NKS-R programs. In year 2008 the NROI project, a Nordic collaboration studying iodine chemistry in the containment, was started. During year 2008 (NROI-1) the radiolytic oxidation of elemental iodine was investigated and during 2009 (NROI-2), the radiolytic oxidation of organic iodine was studied. This project (NROI-3) is a continuation of the investigation of the oxidation of organic iodine. The project has been divided into two parts. 1. The aims of the first part were to investigate the effect of ozone and UV-radiation, in dry and humid conditions, on methyl iodide. 2. The second project was about gamma radiation (approx20 kGy/h) and methyl iodide in dry and humid conditions. 1. Experimental results showed that the methyl iodide concentration in the facility was reduced with increasing temperature and increasing UV-radiation intensity. Similar behaviour occurred when ozone was present in the system. Formed organic gas species during the decomposition of methyl iodide was mainly formaldehyde and methanol. The particle formation was instant and extensive when methyl iodide was exposed to ozone and/or radiation at all temperatures. The size of the formed primary particles was about 10 nm and the size of secondary particles was between 50-200 nm. From the SEM-EDX analyses of the particles, the conclusion was drawn that these were some kind of iodine oxides (I{sub xO{sub y}). However, the correct speciation of the formed particles was difficult to obtain because the particles melted and fused together under the electron beam. 2. The results from this sub-project are more inconsistent and hard to interpret. The particle formation was significant lesser than corresponding experiments when ozone/UV-radiation was used instead of gamma radiation. The transport of gaseous methyl iodide through the facility was

  20. Terbium-doped gadolinium oxysulfide (Gd2O2S:Tb) scintillation-based polymer optical fibre sensor for real time monitoring of radiation dose in oncology

    Science.gov (United States)

    Lewis, E.; O'Keeffe, S.; Grattan, M.; Hounsell, A.; McCarthy, D.; Woulfe, P.; Cronin, J.; Mihai, L.; Sporea, D.; Santhanam, A.; Agazaryan, N.

    2014-05-01

    A PMMA based plastic optical fibre sensor for use in real time radiotherapy dosimetry is presented. The optical fibre tip is coated with a scintillation material, terbium-doped gadolinium oxysulfide (Gd2O2S:Tb), which fluoresces when exposed to ionising radiation (X-Ray). The emitted visible light signal penetrates the sensor optical fibre and propagates along the transmitting fibre at the end of which it is remotely monitored using a fluorescence spectrometer. The results demonstrate good repeatability, with a maximum percentage error of 0.5% and the response is independent of dose rate.

  1. Iodine from bacterial iodide oxidization by Roseovarius spp. inhibits the growth of other bacteria.

    Science.gov (United States)

    Zhao, Dan; Lim, Choon-Ping; Miyanaga, Kazuhiko; Tanji, Yasunori

    2013-03-01

    Microbial activities in brine, seawater, or estuarine mud are involved in iodine cycle. To investigate the effects of the microbiologically induced iodine on other bacteria in the environment, a total of 13 bacteria that potentially participated in the iodide-oxidizing process were isolated from water or biofilm at a location containing 131 μg ml(-1) iodide. Three distinct strains were further identified as Roseovarius spp. based on 16 S rRNA gene sequences after being distinguished by restriction fragment length polymorphism analysis. Morphological characteristics of these three Roseovarius spp. varied considerably across and within strains. Iodine production increased with Roseovarius spp. growth when cultured in Marine Broth with 200 μg ml(-1) iodide (I(-)). When 10(6) CFU/ml Escherichia coli, Pseudomonas aeruginosa, and Bacillus pumilus were exposed to various concentrations of molecular iodine (I(2)), the minimum inhibitory concentrations (MICs) were 0.5, 1.0, and 1.0 μg ml(-1), respectively. However, fivefold increases in the MICs for Roseovarius spp. were obtained. In co-cultured Roseovarius sp. IOB-7 and E. coli in Marine Broth containing iodide (I(-)), the molecular iodine concentration was estimated to be 0.76 μg ml(-1) after 24 h and less than 50 % of E. coli was viable compared to that co-cultured without iodide. The growth inhibition of E. coli was also observed in co-cultures with the two other Roseovarius spp. strains when the molecular iodine concentration was assumed to be 0.52 μg ml(-1).

  2. Synergistic Effect of Azadirachta Indica Extract and Iodide Ions on the Corrosion Inhibition of Aluminium in Acid Media

    Energy Technology Data Exchange (ETDEWEB)

    Arab, S. T.; Al- Turkustani, A. M.; Al- Dhahiri, R. H. [King Abd El- Aziz University, Jeddah (Saudi Arabia)

    2008-06-15

    The synergistic action caused by iodide ions on the corrosion inhibition of aluminium (Al) in 0.5 M HCl in the presence of Azadirachta Indica (AZI) plant extract has been investigated using potintiodynamic polarization and impedance techniques. It is found that AZI extract inhibits the corrosion of aluminium in 0.5 M HCl. The inhibition efficiency increases with the increase in AZI extract concentration, until 24% v/v of AZI extract, then Inh.% is decreased with father increase in AZI extract concentration. The adsorption of this extract in the studied concentration is found to obey Frewendlish adsorption isotherm. The addition of iodide ions enhances the inhibition efficiency to a considerable extent. The increase in Inh.% values in presence of fixed concentration of iodide ions indicates that AZI extract forms an insoluble complex at lower AZI extract concentrations by undergoing a joint adsorption. But at higher concentrations of AZI extract, competitive adsorption is found between iodide ions and the formed complex leading to less Inh.%. The Inh.% decreased in presence of iodide ions with AZI extract than in presence of AZI extract alone at all studied iodide concentrations. The synergism parameter S {sub θ} is defined and calculated from surface coverage values. This parameter in the case of AZI extract is found to be more than unity, indicating that the enhanced inhibition efficiency caused by the addition of iodide ions.

  3. Contrasting the surface ocean distribution of bromoform and methyl iodide; implications for boundary layer physics, chemistry and climate

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, C J, E-mail: carl.j.palmer@gmail.co [Department of Oceanography, University of Cape Town, 7701 (South Africa)

    2010-08-15

    Bromoform and methyl iodide are both methane-like hydrocarbons with a halogen atom replacing one or more of the hydrogen atoms. Both of these compounds occur naturally in the environment as a result of their production from seaweed and kelp. They are of interest to climate science as a result of their catalytic destruction of boundary layer ozone (a potent greenhouse gas) and, specifically for methyl iodide, the proposed role in the formation of new cloud condensation nuclei with implications for climate. In this paper, the currently available data on the distribution of bromoform and methyl iodide are analysed and contrasted to show that the concentrations of bromoform and methyl iodide do not correlate, that, in contrast to bromoform, the parameterization of sea surface methyl iodide concentrations demands only the sea surface temperature, and that the pelagic distribution of methyl iodide appears to follow the solar zenith angle. These three observations together suggest that, while the pelagic source of bromoform is mostly biogenic, the source of methyl iodide is photochemical. This has implications for the understanding of planetary boundary layer chemistry and potential organohalogen mediated feedbacks to climate.

  4. Determination of iodide, iodate and organo-iodine in waters with a new total organic iodine measurement approach.

    Science.gov (United States)

    Gong, Tingting; Zhang, Xiangru

    2013-11-01

    The dissolved iodine species that dominate aquatic systems are iodide, iodate and organo-iodine. These species may undergo transformation to one another and thus affect the formation of iodinated disinfection byproducts during disinfection of drinking waters or wastewater effluents. In this study, a fast, sensitive and accurate method for determining these iodine species in waters was developed by derivatizing iodide and iodate to organic iodine and measuring organic iodine with a total organic iodine (TOI) measurement approach. Within this method, organo-iodine was determined directly by TOI measurement; iodide was oxidized by monochloramine to hypoiodous acid and then hypoiodous acid reacted with phenol to form organic iodine, which was determined by TOI measurement; iodate was reduced by ascorbic acid to iodide and then determined as iodide. The quantitation limit of organo-iodine or sum of organo-iodine and iodide or sum of organo-iodine, iodide and iodate was 5 μg/L as I for a 40 mL water sample (or 2.5 μg/L as I for an 80 mL water sample, or 1.25 μg/L as I for a 160 mL water sample). This method was successfully applied to the determination of iodide, iodate and organo-iodine in a variety of water samples, including tap water, seawater, urine and wastewater. The recoveries of iodide, iodate and organo-iodine were 91-109%, 90-108% and 91-108%, respectively. The concentrations and distributions of iodine species in different water samples were obtained and compared. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Simultaneous reductive dissolution of iron oxide and oxidation of iodide in ice.

    Science.gov (United States)

    Kim, Kitae; Choi, Wonyong

    2015-04-01

    Iron is an important trace element controlling the metabolism and growth of all kinds of living species. Especially, the bio-availability of iron has been regarded as the limiting factor for primary productivity in HNLC (High Nutrients Low Chlorophyll) regions including Southern ocean. The dissolution of iron oxide provides enhanced the bio-availability of iron for phytoplankton growth. The halogen chemistry in polar regions is related to various important environmental processes such as Antarctic Ozone Depletion Event(ODE), mercury depletion, oxidative processes in atmosphere, and the formation of CCN (Cloud Condensation Nuclei). In this study, we investigated the reductive dissolution of iron oxide particles to produce Fe(II)aq and simultaneous oxidation of I- (iodide) to I3- (tri-iodide) in ice phase under UV irradiation or dark condition. The reductive generation of Fe(II)aq from iron oxides and oxidation of iodide to I3- were negligible in water but significantly accelerated in frozen solution both in the presence and absence of light. The enhanced reductive generation of Fe(II)aq and oxidative formation of I3- in ice were observed regardless of the various types of iron oxides [hematite (α-Fe2O3) maghemite (γ- Fe2O3), goethite (α-FeOOH), lepidocrocite (γ-FeOOH) and, magnetite (Fe3O4)]. We explained that the enhanced redox production of Fe(II)aq and I3- in ice is contributed to the freeze concentration of iodides, protons, and dissolved oxygen in the unfrozen solution. When the concentration of both iodides and protons were raised by 10-fold each, the formation of Fe(II)aq in water under UV irradiation was approached to those in ice. The outdoor experiments were carried out under ambient solar radiation in winter season of mid-latitude (Pohang, Korea: 36°N latitude) and also confirmed that the production of Fe(II)aq via reductive dissolution of iron oxide and I3- generation via I- oxidation were enhanced in frozen solution. These results suggest that iron

  6. Experimental study on iodine chemistry (EXSI) - Containment experiments with methyl iodide

    Energy Technology Data Exchange (ETDEWEB)

    Holm, J.; Glaenneskog, H.; Ekberg, C. (Chalmers Univ. of Technology (Sweden)); Kaerkelae, T.; Auvinen, A. (VTT Technical Research Centre of Finland (Finland))

    2010-05-15

    An experimental study on radiolytic decomposition of methyl iodide was conducted in co-operation between VTT and Chalmers University of Technology as a part of the NKS-R programs. The behaviour of iodine during a severe accident has been studied in several experimental programs, ranging from the large-scale PHEBUS FP tests and intermediate-scale ThAI tests to numerous separate effect studies. In year 2008 the NROI project, a Nordic collaboration studying iodine chemistry in the containment was started. During 2009, oxidation of iodine, especially organic iodine, was studied within the NROI project. The chemistry of organic iodine in the gas phase is still one of the greatest remaining uncertainties concerning iodine behaviour during a severe accident. During the first year of the NROI project the oxidation of elemental iodine, I2, with ozone and UV-light was investigated. In this study organic iodide, in this case methyl iodide, was investigated in similar conditions as in the NROI-1 project. The experimental facility applied in this study is based on the sampling system built at VTT for the ISTP project CHIP conducted by IRSN. The experimental facility and the measuring technology are sophisticated and unique in the area of nuclear research as well as in the field of aerosol science. Experimental results showed that the methyl iodide concentration in the facility was reduced with increasing temperature and increasing UVC intensity. Similar behaviour occurred when ozone was present in the system. Formed organic gas species during the decomposition of methyl iodide was mainly formaldehyde and methanol. Instant and extensive particle formation occurred when methyl iodide was transported through a UVC radiation field and/or when ozone was present. The size of the formed primary particles was about 10 nm and the size of secondary particles was between 50-150 nm. From the SEM-EDX analyses of the particles, the conclusion was drawn that these were some kind of iodine

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

    Science.gov (United States)

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

    2010-06-07

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

  8. Picomolar Traces of Americium(III) Introduce Drastic Changes in the Structural Chemistry of Terbium(III): A Break in the "Gadolinium Break".

    Science.gov (United States)

    Welch, Jan M; Müller, Danny; Knoll, Christian; Wilkovitsch, Martin; Giester, Gerald; Ofner, Johannes; Lendl, Bernhard; Weinberger, Peter; Steinhauser, Georg

    2017-10-16

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

  9. Efficacy of propidium iodide and FUN-1 stains for assessing viability in basidiospores of Rhizopogon roseolus.

    Science.gov (United States)

    Fernández-Miranda, Elena; Majada, Juan; Casares, Abelardo

    2017-01-01

    The use of spores in applications of ectomycorrhizal fungi requires information regarding spore viability and germination, especially in genera such as Rhizopogon with high rates of spore dormancy. The authors developed a protocol to assess spore viability of Rhizopogon roseolus using four vital stains to quantify spore viability and germination and to optimize storage procedures. They showed that propidium iodide is an excellent stain for quantifying nonviable spores. Observing red fluorescent intravacuolar structures following staining with 2-chloro-4-(2,3-dihydro-3-methyl-(benzo-1,3-thiazol-2-yl)-methylidene)-1-phenylquinolinium iodide (FUN-1) can help identify viable spores that are activated. At 6 mo and 1 y, the spores kept in a water suspension survived better than those left within intact, dry gasterocarps. Our work highlights the importance of temperature, nutrients, and vitamins for maturation and germination of spores of R. roseolus during 1 y of storage.

  10. The pseudosymmetric structure of bis(pentane-1,5-diaminium iodide tris(triiodide

    Directory of Open Access Journals (Sweden)

    Guido J. Reiss

    2012-05-01

    Full Text Available The asymmetric unit of the title compound, [H3N(CH25NH3]2I[I3]3 or 2C5H16N22+·3I3−·I−, consists of two crystallographically independent pentane-1,5-diaminium dications and two triiodide anions in general positions besides two additional triiodide and two iodide anions located on twofold axes. The compound crystallizes in the centrosymmetric monoclinic space group P2/n. The structure refinement was handicapped by the pseudosymmetry (pseudo-centering of the structure and by twinning. The crystal structure is composed of two alternate layers, which differ in their arrangement of the pentane-1,5-diaminium dications and the iodide/triiodide anions and which are connected via weak to medium–strong N—H...I hydrogen bonds, constructing a complex hydrogen-bonded network.

  11. The pseudosymmetric structure of bis-(pentane-1,5-diaminium) iodide tris-(triiodide).

    Science.gov (United States)

    van Megen, Martin; Reiss, Guido J

    2012-05-01

    The asymmetric unit of the title compound, [H(3)N(CH(2))(5)NH(3)](2)I[I(3)](3) or 2C(5)H(16)N(2) (2+)·3I(3) (-)·I(-), consists of two crystallographically independent pentane-1,5-diaminium dications and two triiodide anions in general positions besides two additional triiodide and two iodide anions located on twofold axes. The compound crystallizes in the centrosymmetric monoclinic space group P2/n. The structure refinement was handicapped by the pseudosymmetry (pseudo-centering) of the structure and by twinning. The crystal structure is composed of two alternate layers, which differ in their arrangement of the pentane-1,5-diaminium dications and the iodide/triiodide anions and which are connected via weak to medium-strong N-H⋯I hydrogen bonds, constructing a complex hydrogen-bonded network.

  12. Gap energy studied by optical transmittance in lead iodide monocrystals grown by Bridgman's Method

    Directory of Open Access Journals (Sweden)

    Veissid N.

    1999-01-01

    Full Text Available The bandgap energy as a function of temperature has been determined for lead iodide. The monocrystal was obtained in a vacuum sealed quartz ampoule inside a vertical furnace by Bridgman's method. The optical transmittance measurement enables to evaluate the values of Eg. By a fitting procedure of Eg as a function of temperature is possible to extract the parameters that govern its behavior. The variation of Eg with temperature was determined as: Eg(T = Eg(0 - aT2/(a + T, with: Eg(0 = (2.435 ± 0.008 eV, a = (8.7 ± 1.3 x 10-4 eV/K and a = (192 ± 90 K. The bandgap energy of lead iodide at room temperature was found to be 2.277 ± 0.007 eV.

  13. Induction of iodide uptake in transformed thyrocytes: a compound screening in cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Froehlich, Eleonore [University of Tuebingen, Department of Endocrinology, Metabolism, Nephrology and Clinical Chemistry, Internal Medicine, Tuebingen (Germany); Brossart, Peter [University of Tuebingen, Department of Haematology, Oncology, Immunology and Rheumatology, Internal Medicine, Tuebingen (Germany); Wahl, Richard [University of Tuebingen, Department of Endocrinology, Metabolism, Nephrology and Clinical Chemistry, Internal Medicine, Tuebingen (Germany); Department IV, Internal Medicine, Tuebingen (Germany)

    2009-05-15

    Retinoic acid presently is the most advanced agent able to improve the efficacy of radioiodine therapy in differentiated thyroid carcinoma. In order to identify compounds with higher efficacy a panel of pharmacologically well-characterized compounds with antitumour action in solid cancer cell lines was screened. The effects of the compounds on iodide uptake, cell number, proliferation and apoptosis were evaluated. In general, compounds were more effective in cell lines derived from more aggressive tumours. The effectiveness in terms of number of responsive cell lines and maximal increase in iodide uptake achieved decreased in the order: APHA > valproic acid {approx} sirolimus {approx} arsenic trioxide > retinoic acid {approx} lovastatin > apicidine {approx} azacytidine {approx} retinol {approx} rosiglitazone {approx} bortezomib. We hypothesize that testing of cells from primary tumours or metastases in patients may be a way to identify compounds with optimum therapeutic efficacy for individualized treatment. (orig.)

  14. Synthesis, spectral, and anti-microbial studies of thioiminium iodides and amine hydrochlorides.

    Science.gov (United States)

    Britto, Sebastian; Renaud, Philippe; Nallu, Maruthai

    2014-01-01

    To avoid the undesired deprotonation during the addition of organolithium and organomagnesium reagents to ketones, the thioiminium salts, easily prepared from lactams and amides are converted into 2,2-disubstituted and 2-monosubstituted amines by reaction with simple nucleophiles such as organocerium and organocopper reagents. The reaction of thioiminium iodides with organocerium reagents derived by transmetalation of corresponding lithium reagents with anhydrous cerium(III) chloride has been investigated. These thioiminium iodides act as good electrophiles and accept alkylceriums towards bisaddition. The newly synthesized amines have been characterized by 1H and 13C NMR, IR and mass spectra. The amines have been converted into their hydrochlorides and characterized by COSY. These hydrochlorides have been subjected to antimicrobial screening with clinically isolated microorganisms, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi and Candida albicans. The hydrochlorides show quite good activity against these bacteria and fungus. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. DEVELOPMENT OF A SCREENING APPROACH TO DETECT THYROID DISRUPTING CHEMICALS THAT INHIBIT THE HUMAN SODIUM IODIDE SYMPORTER (NIS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data pertaining to a NIS-expressing cell line, hNIS-HEK293T-EPA, and its screening capabilities for determining inhibitors of NIS-mediated iodide uptake. This...

  16. Cooperative effect of silver in copper-catalyzed trifluoromethylation of aryl iodides using Me3SiCF3

    KAUST Repository

    Weng, Zhiqiang

    2011-06-13

    An effective model of cooperative effect of silver for the coppercatalyzed trifluoromethylation of activated and unactivated aryl iodides to trifluoromethylated arenes using Me3SiCF3 was achieved with a broad substrate scope. © 2011 American Chemical Society.

  17. Kinetic-Spectrophotometric Determination of Iodide Based on its Inhibitory Effect on the Decolorization Reaction of Methyl Orange

    Directory of Open Access Journals (Sweden)

    Reyhaneh Rahnama Kozani

    2009-01-01

    Full Text Available A simple, sensitive, rapid and reliable method has been developed for spectrophotometric determination of iodide based on its inhibition effect on the redox reaction between bromate and hydrochloric acid. The decolorization of methyl orange by the reaction products was used to monitor the reaction spectrophotometrically at 525 nm. The variables affecting the rate of the reaction were investigated. Under the optimum conditions, the limit of detection is 1.5 × 10-7 mol L-1 and calibration range is 2.0 × 10-6–1.3 × 10-4 mol L-1 of iodide. The linearity range of the calibration graph is depends on bromate concentration. The relative standard deviation of ten-replication determination of 8.2 × 10-5 mol L-1 iodide was 1.4%. The proposed method was applied to the determination of iodide in natural water samples with satisfactory results.

  18. Studies on the Mechanisms of Methyl Iodide Adsorption and Iodine Retention on Silver-Mordenite

    Energy Technology Data Exchange (ETDEWEB)

    Nenoff, Tina Maria [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Soelberg, Nick [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    Silver-containing mordenite (MOR) is a longstanding benchmark for radioiodine capture, reacting with molecular iodine (I2) to form AgI. However the mechanisms for organoiodine capture are not well understood. Here we investigate the capture of methyl iodide from complex mixed gas streams by combining chemical analysis of the effluent gas stream with in depth characterization of the recovered sorbent.

  19. Methyl Iodide Oxidative Addition to Rhodium(I) Complexes: a DFT ...

    African Journals Online (AJOL)

    NJD

    Isomerization via an acyl intermediate leads to a second octahedral alkyl product with the PPh3 group and the iodide above ... erties of the different ligands to determine the relative rates of the two most important steps of the ...... V.G. Zakrzewski, S. Dapprich, A.D. Daniels, M.C. Strain, O. Farkas,. D.K. Malick, A.D. Rabuck, ...

  20. Samarium(II) iodide-mediated reductive annulations of ketones bearing a distal vinyl epoxide moiety

    Energy Technology Data Exchange (ETDEWEB)

    Molander, G.A.; Shakya, S.R. [Univ. of Colorado, Boulder, CO (United States)

    1996-08-23

    It was found that samarium (II) iodide promotes the intramolecular coupling of ketones with distal epoxy olefins while in the presence of hexamethylphosphoramide (HPMA). A number of epoxide compounds (1 a-k) fragment to form carbocycles with allylic alcohol side chains with high diastereoselectivity (2 a-k). Substituting tetramethylguanidine for HPMA reduces the diastereoselectivity. Adding Pd(0) as a catalyst reverses the diastereoselective sense. 40 refs., 1 tab.

  1. Palladium(II)-catalyzed regioselective arylation of naphthylamides with aryl iodides utilizing a quinolinamide bidentate system.

    Science.gov (United States)

    Huang, Lehao; Li, Qian; Wang, Chen; Qi, Chenze

    2013-04-05

    A palladium(II)-catalyzed quinolinamide-directed 8-arylation of 1-naphthylamides with aryl iodides is reported. The bidentate directing group (quinolinamide) proved to be crucial for a highly regioselective transformation. In addition, the amide directing group can be easily hydrolyzed under basic conditions to offer a range of 8-aryl-1-naphthylamine derivatives. The theoretical calculations suggest that the C-H arylation reaction proceeds through a sequential C-H activation/oxidative addition pathway.

  2. ' FLUORIDE (STFZ) AND Bl'§RYi_.§?.ll't/I IODIDE (Belg) THIN

    African Journals Online (AJOL)

    ohm-cm)“. ', film thickness 0.013 to 0. ()74pm and band gap 2.65 to 2. 75 j; 0. 05eV. For berylium iodide films the absorbance ranges from 0.204 to 0.302, transmittance 0.499 to 0.625, refractive index 2.41 to. 2.61, electrical conductivity 0.62 to 0.

  3. Nitro-Grela-type complexes containing iodides - robust and selective catalysts for olefin metathesis under challenging conditions.

    Science.gov (United States)

    Tracz, Andrzej; Matczak, Mateusz; Urbaniak, Katarzyna; Skowerski, Krzysztof

    2015-01-01

    Iodide-containing nitro-Grela-type catalysts have been synthesized and applied to ring closing metathesis (RCM) and cross metathesis (CM) reactions. These new catalysts have exhibited improved efficiency in the transformation of sterically, non-demanding alkenes. Additional steric hindrance in the vicinity of ruthenium related to the presence of iodides ensures enhanced catalyst stability. The benefits are most apparent under challenging conditions, such as very low reaction concentrations, protic solvents or with the occurrence of impurities.

  4. Nitro-Grela-type complexes containing iodides – robust and selective catalysts for olefin metathesis under challenging conditions

    Directory of Open Access Journals (Sweden)

    Andrzej Tracz

    2015-10-01

    Full Text Available Iodide-containing nitro-Grela-type catalysts have been synthesized and applied to ring closing metathesis (RCM and cross metathesis (CM reactions. These new catalysts have exhibited improved efficiency in the transformation of sterically, non-demanding alkenes. Additional steric hindrance in the vicinity of ruthenium related to the presence of iodides ensures enhanced catalyst stability. The benefits are most apparent under challenging conditions, such as very low reaction concentrations, protic solvents or with the occurrence of impurities.

  5. Gas-phase pesticide measurement using iodide ionization time-of-flight mass spectrometry

    Science.gov (United States)

    Murschell, Trey; Fulgham, S. Ryan; Farmer, Delphine K.

    2017-06-01

    Volatilization and subsequent processing in the atmosphere are an important environmental pathway for the transport and chemical fate of pesticides. However, these processes remain a particularly poorly understood component of pesticide lifecycles due to analytical challenges in measuring pesticides in the atmosphere. Most pesticide measurements require long (hours to days) sampling times coupled with offline analysis, inhibiting observation of meteorologically driven events or investigation of rapid oxidation chemistry. Here, we present chemical ionization time-of-flight mass spectrometry with iodide reagent ions as a fast and sensitive measurement of four current-use pesticides. These semi-volatile pesticides were calibrated with injections of solutions onto a filter and subsequently volatilized to generate gas-phase analytes. Trifluralin and atrazine are detected as iodide-molecule adducts, while permethrin and metolachlor are detected as adducts between iodide and fragments of the parent analyte molecule. Limits of detection (1 s) are 0.37, 0.67, 0.56, and 1.1 µg m-3 for gas-phase trifluralin, metolachlor, atrazine, and permethrin, respectively. The sensitivities of trifluralin and metolachlor depend on relative humidity, changing as much as 70 and 59, respectively, as relative humidity of the sample air varies from 0 to 80 %. This measurement approach is thus appropriate for laboratory experiments and potentially near-source field measurements.

  6. Toxic impact of bromide and iodide on drinking water disinfected with chlorine or chloramines.

    Science.gov (United States)

    Yang, Yang; Komaki, Yukako; Kimura, Susana Y; Hu, Hong-Ying; Wagner, Elizabeth D; Mariñas, Benito J; Plewa, Michael J

    2014-10-21

    Disinfectants inactivate pathogens in source water; however, they also react with organic matter and bromide/iodide to form disinfection byproducts (DBPs). Although only a few DBP classes have been systematically analyzed for toxicity, iodinated and brominated DBPs tend to be the most toxic. The objectives of this research were (1) to determine if monochloramine (NH2Cl) disinfection generated drinking water with less toxicity than water disinfected with free chlorine (HOCl) and (2) to determine the impact of added bromide and iodide in conjunction with HOCl or NH2Cl disinfection on mammalian cell cytotoxicity and genomic DNA damage induction. Water disinfected with chlorine was less cytotoxic but more genotoxic than water disinfected with chloramine. For both disinfectants, the addition of Br(-) and I(-) increased cytotoxicity and genotoxicity with a greater response observed with NH2Cl disinfection. Both cytotoxicity and genotoxicity were highly correlated with TOBr and TOI. However, toxicity was weakly and inversely correlated with TOCl. Thus, the forcing agents for cytotoxicity and genotoxicity were the generation of brominated and iodinated DBPs rather than the formation of chlorinated DBPs. Disinfection practices need careful consideration especially when using source waters containing elevated bromide and iodide.

  7. Grotthuss Transport of Iodide in EMIM/I3 Ionic Crystal.

    Science.gov (United States)

    McDaniel, Jesse Gatten; Yethiraj, Arun

    2017-12-01

    Highly ionic environments can mediate unusual chemical reactions that would otherwise be considered impossible based on chemical intuition. For example, the formation of a chemical bond between two iodide anions to form a divalent polyiodide anion is seemingly prohibited due to Coulombic repulsion. Using ab initio molecular dynamics simulations, we show that in the 1-ethyl-3-methylimidazolium (EMIM)/I3 ionic crystal, the reactive formation of divalent and even trivalent polyiodide anions occurs with extremely small energetic barriers, due to the electrostatic field of the ionic lattice. A practical consequence of this anomalous reactivity is that iodide anions are efficiently transported within the crystal through a "Grotthuss-exchange" mechanism involving bond-breaking and forming events. We characterize two distinct transport pathways, involving both I2- 4 and I3- 7 intermediates, with fast transport of iodide resulting from the release of an I- anion on the opposite side of the intermediate species from the initial bond formation. The ordered cation arrangement in the crystal provides the necessary electrostatic screening for close approach of anions, suggesting a new counter-intuitive approach to obtain high ionic conductivity. This new design principle could be used to develop better solid-state electrolytes for batteries, fuel cells and super-capacitors.

  8. A reversible fluorescent logic gate for sensing mercury and iodide ions based on a molecular beacon.

    Science.gov (United States)

    Wu, Xu; Chen, Jiao; Zhao, Julia Xiaojun

    2013-09-21

    A simple, rapid, and reversible fluorescent DNA INHIBIT logic gate has been developed for sensing mercury (Hg(2+)) and iodide (I(-)) ions based on a molecular beacon (MB). In this logic gate, a mercury ion was introduced as the first input into the MB logic gate system to assist in the hybridization of the MB with an assistant DNA probe through the thymine-Hg(2+)-thymine interaction, which eventually restored the fluorescence of MB as the output. With this signal-on process, mercury ions can be detected with a limit of detection as low as 7.9 nM. Furthermore, when iodide ions were added to the Hg(2+)/MB system as the second input, the fluorescence intensity decreased because Hg(2+) in the thymine-Hg(2+)-thymine complex was grabbed by I(-) due to a stronger binding force. Iodide ions can be detected with a limit of detection of 42 nM. Meanwhile, we studied the feasibility and basic performance of the DNA INHIBIT logic gate, optimized the logic gate conditions, and investigated its sensitivity and selectivity. The results showed that the MB based logic gate is highly selective and sensitive for the detection of Hg(2+) and I(-) over other interfering cations and anions.

  9. Ab initio calculation of transport properties between PbSe quantum dots facets with iodide ligands

    Science.gov (United States)

    Wang, B.; Patterson, R.; Chen, W.; Zhang, Z.; Yang, J.; Huang, S.; Shrestha, S.; Conibeer, G.

    2018-01-01

    The transport properties between Lead Selenide (PbSe) quantum dots decorated with iodide ligands has been studied using density functional theory (DFT). Quantum conductance at each selected energy levels has been calculated along with total density of states and projected density of states. The DFT calculation is carried on using a grid-based planar augmented wave (GPAW) code incorporated with the linear combination of atomic orbital (LCAO) mode and Perdew Burke Ernzerhof (PBE) exchange-correlation functional. Three iodide ligand attached low index facets including (001), (011), (111) are investigated in this work. P-orbital of iodide ligand majorly contributes to density of state (DOS) at near top valence band resulting a significant quantum conductance, whereas DOS of Pb p-orbital shows minor influence. Various values of quantum conductance observed along different planes are possibly reasoned from a combined effect electrical field over topmost surface and total distance between adjacent facets. Ligands attached to (001) and (011) planes possess similar bond length whereas it is significantly shortened in (111) plane, whereas transport between (011) has an overall low value due to newly formed electric field. On the other hand, (111) plane with a net surface dipole perpendicular to surface layers leading to stronger electron coupling suggests an apparent increase of transport probability. Apart from previously mentioned, the maximum transport energy levels located several eVs (1 2 eVs) from the edge of valence band top.

  10. A Role for Iodide and Thyroglobulin in Modulating the Function of Human Immune Cells

    Directory of Open Access Journals (Sweden)

    Mahmood Y. Bilal

    2017-11-01

    Full Text Available Iodine is an essential element required for the function of all organ systems. Although the importance of iodine in thyroid hormone synthesis and reproduction is well known, its direct effects on the immune system are elusive. Human leukocytes expressed mRNA of iodide transporters (NIS and PENDRIN and thyroid-related proteins [thyroglobulin (TG and thyroid peroxidase (TPO]. The mRNA levels of PENDRIN and TPO were increased whereas TG transcripts were decreased post leukocyte activation. Flow cytometric analysis revealed that both PENDRIN and NIS were expressed on the surface of leukocyte subsets with the highest expression occurring on monocytes and granulocytes. Treatment of leukocytes with sodium iodide (NaI resulted in significant changes in immunity-related transcriptome with an emphasis on increased chemokine expression as probed with targeted RNASeq. Similarly, treatment of leukocytes with NaI or Lugol’s iodine induced increased protein production of both pro- and anti-inflammatory cytokines. These alterations were not attributed to iodide-induced de novo thyroid hormone synthesis. However, upon incubation with thyroid-derived TG, primary human leukocytes but not Jurkat T cells released thyroxine and triiodothyronine indicating that immune cells could potentially influence thyroid hormone balance. Overall, our studies reveal the novel network between human immune cells and thyroid-related molecules and highlight the importance of iodine in regulating the function of human immune cells.

  11. Iodide, bromide, and ammonium in hydraulic fracturing and oil and gas wastewaters: environmental implications.

    Science.gov (United States)

    Harkness, Jennifer S; Dwyer, Gary S; Warner, Nathaniel R; Parker, Kimberly M; Mitch, William A; Vengosh, Avner

    2015-02-03

    The expansion of unconventional shale gas and hydraulic fracturing has increased the volume of the oil and gas wastewater (OGW) generated in the U.S. Here we demonstrate that OGW from Marcellus and Fayetteville hydraulic fracturing flowback fluids and Appalachian conventional produced waters is characterized by high chloride, bromide, iodide (up to 56 mg/L), and ammonium (up to 420 mg/L). Br/Cl ratios were consistent for all Appalachian brines, which reflect an origin from a common parent brine, while the I/Cl and NH4/Cl ratios varied among brines from different geological formations, reflecting geogenic processes. There were no differences in halides and ammonium concentrations between OGW originating from hydraulic fracturing and conventional oil and gas operations. Analysis of discharged effluents from three brine treatment sites in Pennsylvania and a spill site in West Virginia show elevated levels of halides (iodide up to 28 mg/L) and ammonium (12 to 106 mg/L) that mimic the composition of OGW and mix conservatively in downstream surface waters. Bromide, iodide, and ammonium in surface waters can impact stream ecosystems and promote the formation of toxic brominated-, iodinated-, and nitrogen disinfection byproducts during chlorination at downstream drinking water treatment plants. Our findings indicate that discharge and accidental spills of OGW to waterways pose risks to both human health and the environment.

  12. The chlorination transformation characteristics of benzophenone-4 in the presence of iodide ions.

    Science.gov (United States)

    Yang, Fan; Wei, Dongbin; Xiao, Ming; Sun, Xuefeng; Guo, Qiaorong; Liu, Yi; Du, Yuguo

    2017-08-01

    Benzophenone-type UV filters are a group of compounds widely used to protect human skin from damage of UV irradiation. Benzophenone-4 (BP-4) was targeted to explore its transformation behaviors during chlorination disinfection treatment in the presence of iodide ions. With the help of ultra performance liquid phase chromatograph and high-resolution quadrupole time-of-flight mass spectrometer, totally fifteen halogenated products were identified, and five out of them were iodinated products. The transformation mechanisms of BP-4 involved electrophilic substitution generating mono- or di-halogenated products, which would be oxidized into esters and further hydrolyzed into phenolic derivatives. The desulfonation and decarboxylation were observed in chlorination system either. Obeying the transformation pathways, five iodinated products formed. The pH conditions of chlorination system determined the reaction types of transformation and corresponding species of products. The more important was that, the acute toxicity had significant increase after chlorination treatment on BP-4, especially in the presence of iodide ions. When the chlorination treatment was performed on ambient water spiked with BP-4 and iodide ions, iodinated by-products could be detected. Copyright © 2017. Published by Elsevier B.V.

  13. Simple and rapid determination of iodide in table salt by stripping potentiometry at a carbon-paste electrode.

    Science.gov (United States)

    Svancara, Ivan; Ogorevc, Bozidar; Nović, Milko; Vytras, Karel

    2002-04-01

    A simple and rapid procedure, utilising constant-current stripping analysis (CCSA) at a carbon-paste electrode containing tricresyl phosphate as a pasting liquid (TCP-CPE), has been developed for the determination of iodide in table salt. Because of a synergistic accumulation mechanism based on ion-pairing and extraction of iodide in combination with electrolytic pretreatment of the TCP-CPE, the method is selective for iodide and enables direct determination of iodide in samples of table salt containing anti-caking agents such as K(4)[Fe(CN)(6)] (food additive "E 536") or MgO. The iodide content (calculated as KI) can be determined in a concentration range of 2 to 100 mg kg(-1) salt, with a detection limit (S/N=3) of 1 mg kg(-1), and a recovery from 90 to 115%. The proposed method has been used to determine iodide in several types of artificially iodised table salt and in one sample of natural sea salt. The results obtained agreed well with those obtained by use of three independent reference methods (titration, spectrophotometry, and ICP-MS) used to validate the CCSA method, indicating that the developed method is applicable as a routine procedure for rapid testing in salt production process control and in the analysis of marketed table salts.

  14. Identification of delta-iodolactone in iodide treated human goiter and its inhibitory effect on proliferation of human thyroid follicles.

    Science.gov (United States)

    Dugrillon, A; Uedelhoven, W M; Pisarev, M A; Bechtner, G; Gärtner, R

    1994-10-01

    There is evidence that iodoarachidonates are mediators of iodide in thyroid autoregulation, however, their occurrence in vivo has not yet been demonstrated. We therefore tried to identify delta-iodolactone (5-Hydroxy-6-iodo-8,11,14-eicosatrienoic delta-lactone, IL-delta) in thyroid tissue from a patient with Graves' disease treated with high doses of iodide. Lipids were extracted from thyroid tissue, purified by reversed phase chromatography and analyzed by gas chromatography--tandem mass spectrometry (GC-MSMS). The retention time in gas chromatography and fragmentation pattern in tandem mass spectrometry were determined with biochemically synthesized non-deuterated and deuterated IL-delta. According to retention time (13.44 min) and specific fragments (m/z 303, m/z 259) the occurrence of IL-delta could be demonstrated in the extract of iodide treated goiter. In vitro, potassium iodide (40 microM) as well as IL-delta (1.0 microM) significantly inhibited the proliferation of human thyroid follicular cells induced by phorbol ester TPA (12-O-tetradecanoylphorbol 13-acetate). These results demonstrate for the first time that Il-delta is present in iodide treated human thyroid. As cell proliferation is under negative control of IL-delta, a crucial role in thyroid involution following iodide treatment may be possible.

  15. Reduction of stimulated sodium iodide symporter expression by estrogen receptor ligands in breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Su-Jin; Jang, DooRye; Jeong, Hwan-Jeong; Lim, Seok Tae; Sohn, Myung-Hee [Department of Nuclear Medicine, Cyclotron Research Center, Research Institute of Clinical Medicine, Chonbuk National University Medical School, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Katzenellenbogen, John A., E-mail: jkatzene@illinois.ed [Department of Chemistry, University of Illinois, Urbana, IL 61801 (United States); Kim, Dong Wook, E-mail: kimdw@chonbuk.ac.k [Department of Nuclear Medicine, Cyclotron Research Center, Research Institute of Clinical Medicine, Chonbuk National University Medical School, Jeonju, Jeonbuk 561-756 (Korea, Republic of)

    2011-02-15

    Purpose: The sodium iodide symporter (NIS) mediates active iodide uptake in lactating breast tissue, and when its levels are enhanced by all-trans retinoic acid (atRA), NIS has been proposed as a target for the imaging and radiotherapy of breast cancer. Importantly, the estrogen receptor {alpha} (ER{alpha}) is an important regulator of atRA induced NIS gene expression in breast cancer cells. In this study, we investigated the effect of an ER agonist (17{beta}-estradiol, E{sub 2}) or antagonist [trans-hydroxytamoxifen (TOT) or raloxifene (RAL)] treatment on the regulation of NIS gene expression and iodide uptake in an ER{alpha}-positive breast cancer (MCF-7) model. Methods: NIS functional activity was measured in vitro by {sup 125}I uptake assay after incubation with E{sub 2} (from 10{sup -15} to 10{sup -5} M), TOT (from 5x10{sup -8} to 5x10{sup -6} M), or RAL (from 5x10{sup -8} to 5x10{sup -6} M) in the presence or absence of atRA (10{sup -7} M). Under the same conditions, NIS mRNA expression was examined by reverse transcriptase polymerase chain reaction. Athymic mice with MCF-7 xenograft tumors were treated with atRA alone or atRA together with E{sub 2} to evaluate the change of {sup 125}I uptake in tumor tissues in vivo. Results: In the iodide uptake study in cells, E{sub 2}, TOT, or RAL treatment alone did not stimulate {sup 125}I uptake. However, when iodide uptake was stimulated by atRA, cotreatment with E{sub 2}, TOT or RAL decreased {sup 125}I uptake in a concentration-dependent manner. The hormone effects on NIS mRNA expression levels in MCF-7 cells were similar. The results of the in vivo biodistribution study showed that {sup 125}I uptake was reduced 50% in tumor tissues of mice treated with atRA/E{sub 2} as compared to tumors treated only with atRA. Conclusion: Our results suggest that combination treatment of atRA and ER ligands could limit the functional activity of the NIS gene induced by atRA, thereby compromising its use as a target for diagnosis

  16. Crystal structures of two mononuclear complexes of terbium(III) nitrate with the tripodal alcohol 1,1,1-tris-(hy-droxy-meth-yl)propane.

    Science.gov (United States)

    Gregório, Thaiane; Giese, Siddhartha O K; Nunes, Giovana G; Soares, Jaísa F; Hughes, David L

    2017-02-01

    Two new mononuclear cationic complexes in which the TbIII ion is bis-chelated by the tripodal alcohol 1,1,1-tris-(hy-droxy-meth-yl)propane (H3LEt, C6H14O3) were prepared from Tb(NO3)3·5H2O and had their crystal and mol-ecular structures solved by single-crystal X-ray diffraction analysis after data collection at 100 K. Both products were isolated in reasonable yields from the same reaction mixture by using different crystallization conditions. The higher-symmetry complex dinitratobis[1,1,1-tris-(hy-droxy-meth-yl)propane]-terbium(III) nitrate di-meth-oxy-ethane hemisolvate, [Tb(NO3)2(H3LEt)2]NO3·0.5C4H10O2, 1, in which the lanthanide ion is 10-coordinate and adopts an s-bicapped square-anti-prismatic coordination geometry, contains two bidentate nitrate ions bound to the metal atom; another nitrate ion functions as a counter-ion and a half-mol-ecule of di-meth-oxy-ethane (completed by a crystallographic twofold rotation axis) is also present. In product aqua-nitratobis[1,1,1-tris-(hy-droxy-meth-yl)propane]-terbium(III) dinitrate, [Tb(NO3)(H3LEt)2(H2O)](NO3)2, 2, one bidentate nitrate ion and one water mol-ecule are bound to the nine-coordinate terbium(III) centre, while two free nitrate ions contribute to charge balance outside the tricapped trigonal-prismatic coordination polyhedron. No free water mol-ecule was found in either of the crystal structures and, only in the case of 1, di-meth-oxy-ethane acts as a crystallizing solvent. In both mol-ecular structures, the two tripodal ligands are bent to one side of the coordination sphere, leaving room for the anionic and water ligands. In complex 2, the methyl group of one of the H3LEt ligands is disordered over two alternative orientations. Strong hydrogen bonds, both intra- and inter-molecular, are found in the crystal structures due to the number of different donor and acceptor groups present.

  17. AC-93253 iodide, a novel Src inhibitor, suppresses NSCLC progression by modulating multiple Src-related signaling pathways

    Directory of Open Access Journals (Sweden)

    Yi-Hua Lai

    2017-11-01

    Full Text Available Abstract Background The tyrosine kinase Src is involved in the progression of many cancers. Moreover, inhibiting Src activity has been shown to obstruct several signaling pathways regulated by the EGFR. Thus, Src is a valuable target molecule in drug development. The purpose of this study was to identify compounds that directly or indirectly modulate Src to suppress lung cancer cell growth and motility and to investigate the molecular mechanisms underlying the effects of these compounds. Methods Human non-small cell lung cancer (NSCLC cell lines (PC9, PC9/gef, A549, and H1975 with different EGFR statuses were tested by cytotoxicity and proliferation assays after AC-93253 iodide treatment. Src and Src-related protein expression in AC-93253 iodide-treated PC9, PC9/gef, and A549 cells were assessed by western blotting. The effects of AC-93253 iodide on cancer cell colony formation, invasion, and migration were assessed in PC9 and PC9/gef cells. The synergistic effects of gefitinib and AC-93253 iodide were evaluated by combination index (CI-isobologram analysis in gefitinib-resistant cell lines. The efficacy of AC-93253 iodide in vivo was determined using nude mice treated with either the compound or the vehicle. Results Among the compounds, AC-93253 iodide exhibited the most potent dose-independent inhibitory effects on the activity of Src as well as on that of the Src-related proteins EGFR, STAT3, and FAK. Furthermore, AC-93253 iodide significantly suppressed cancer cell proliferation, colony formation, invasion, and migration in vitro and tumor growth in vivo. AC-93253 iodide sensitized tumor cells to gefitinib treatment regardless of whether the cells were gefitinib-sensitive (PC9 or resistant (H1975 and PC9/gef, indicating that it may exert synergistic effects when used in combination with established therapeutic agents. Our findings also suggested that the inhibitory effects of AC-93253 iodide on lung cancer progression may be attributable to

  18. Aqueous photochemical reactions of chloride, bromide, and iodide ions in a diode-array spectrophotometer. Autoinhibition in the photolysis of iodide ions.

    Science.gov (United States)

    Kalmár, József; Dóka, Éva; Lente, Gábor; Fábián, István

    2014-03-28

    The aqueous photoreactions of three halide ions (chloride, bromide and iodide) were studied using a diode array spectrophotometer to drive and detect the process at the same time. The concentration and pH dependences of the halogen formation rates were studied in detail. The experimental data were interpreted by improving earlier models where the cage complex of a halogen atom and an electron has a central role. The triiodide ion was shown to exert a strong inhibiting effect on the reaction sequence leading to its own formation. An assumed chemical reaction between the triiodide ion and the cage complex interpreted the strong autoinhibition effect. It is shown that there is a real danger of unwanted interference from the photoreactions of halide ions when halide salts are used as supporting electrolytes in spectrophotometric experiments using a relatively high intensity UV light source.

  19. The response behavior of PPy-DB18C6 electrode to terbium(III in acetonitrile and its thermodynamic application

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Arbab Zavar

    2016-11-01

    Full Text Available Polypyrrole modified electrode prepared by electropolymerization of pyrrole in the presence of a complexing ligand, dibenzo-18-crown-6(DB18C6, was prepared and investigated as a Tb3+-selective electrode in acetonitrile. The potentiometric response of the electrode was linear within the Tb3+ concentration range 1 × 10−5–1 × 10−2 M with a Nernstian slope of 20.9 mVdecade−1 in AN. The electrode was applied to study the complexation of the terbium(III ion in acetonitrile with such other basic aprotic solvent molecules (D as dimethyl sulfoxide, N,N-dimethyl formamide, propylene carbonate and pyridine. The successive complex formation constant (βi and Gibbs energies of transfer (ΔGtr of Tb3+ in AN in relation to such D were obtained.

  20. Luminescence and Magnetic Properties of Two Three-Dimensional Terbium and Dysprosium MOFs Based on Azobenzene-4,4′-Dicarboxylic Linker

    Directory of Open Access Journals (Sweden)

    Belén Fernández

    2016-02-01

    Full Text Available We report the in situ formation of two novel metal-organic frameworks based on terbium and dysprosium ions using azobenzene-4,4′-dicarboxylic acid (H2abd as ligand, synthesized by soft hydrothermal routes. Both materials show isostructural three-dimensional networks with channels along a axis and display intense photoluminescence properties in the solid state at room temperature. Textural properties of the metal-organic frameworks (MOFs have been fully characterized although no appreciable porosity was obtained. Magnetic properties of these materials were studied, highlighting the dysprosium material displays slightly frequency-dependent out of phase signals when measured under zero external field and under an applied field of 1000 Oe.

  1. Towards a biochemical and structural characterisation of the sodium-iodide sym-porter (Nis)

    Energy Technology Data Exchange (ETDEWEB)

    Darrouzet, E.; Marcellin, D.; Huc, S.; Quemeneur, E. [CEA Centre de Marcoule (SBTN), 30 - Bagnols-sur-Ceze (France); Pourcher, T. [Nice Univ., TIRO CEA, Sophia Antipolis, 06 - Nice (France)

    2006-07-01

    Iodide is essential for thyroid hormone biosynthesis in mammals, and therefore for the control of cell metabolism and the development of the central nervous system in the foetus and newborns, but is relatively scarce element in the environment. To ensure its accumulation, the thyroid gland has evolved a remarkably efficient system, the sodium-iodide sym-porter (NIS), that was first characterized at the molecular level 10 years ago (1). NIS is an intrinsic protein mainly located in the basolateral membrane of thyroid follicular cells where it actively transports iodide ions using the sodium gradient as a driving force (2,3). In addition, this transporter has been found in lactating mammary gland, stomach, and salivary glands, and its mRNA was detected in brain, ovaries, testis. To date, the physiological role of NIS in these organs is not yet identified (3,4).The capacity of NIS to mediate the accumulation of radioactive iodide has been exploited for many years in the diagnosis of thyroid cancer as well as for the detection and radiotherapy of derived metastases. Moreover, the presence of NIS in some breast tumours and the possibility to express it by targeted gene therapy in tumour cells where it is not naturally present could also widen its medical application (4-7). In case of accidental contamination, NIS would also be responsible for accumulation of radioisotopes in the thyroid and for their transfer to the milk and the newborn, eventually causing thyroid cancers. This has motivated our research program in the perspective of designing novel specific therapeutics. During the last decade, the gene encoding the thyroid NIS has been identified and sequenced in various species including rat, mouse and human (1, 8). It was also demonstrated that the protein expression and activity are highly regulated both at the transcriptional and post-translational levels (3). A preliminary topological mode could be drawn from the protein sequence. It proposes a general

  2. [The analysis for silver iodide fine particles of TLC/FTIR matrix].

    Science.gov (United States)

    Zhu, Qing; Su, Xiao; Wu, Hai-Jun; Zhai, Yan-Jun; Xia, Jin-Ming; Buhebate; Xu, Yi-Zhuang; Wu, Jin-Guang

    2012-07-01

    In situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase has strong absorption in FTIR spectrum and thus brings about severe interference in the detection of samples. To solve the problem, the authors propose to use AgI fine particles as stationary phase of TLC plate. The reasons are as follows: Silver iodide fine particles have no absorbance in an IR region between 4 000 and 800 cm(-1), therefore, the interference caused by IR absorption of stationary phase can be removed. Moreover, silver iodide is stable and insolvable in water and organic solvents and thus it will not be destroyed by mobile phase or react with samples during the TLC separation. To improve TLC separation efficiency and quality of FTIR spectra during the TLC/FTIR analysis, the size of AgI particles should be below 500 nm. We used orthogonal design approach to optimize the experimental condition to AgI particles so that the average size of AgI particles is around 100 nm. No absorption of impurity or adsorbed water were observed in FTIR spectrum of the AgI particles the authors used "settlement volatilization method" to prepare TLC plate without using polymeric adhesive that may bring about significant interference in FTIR analysis. Preliminary TLC experiments proved that the TLC plate using AgI fine particles as stationary phase can separate mixtures of rhodamine B and bromophenol blue successfully. Applications of silver iodide fine particles as stationary phase have bright perspective in the development of in-situ TLC/FTIR analysis techniques.

  3. Titrimetric and spectrophotometric assay of diethylcarbamazine citrate in formulations using iodate and iodide mixture as reagents

    Directory of Open Access Journals (Sweden)

    Nagaraju Swamy

    2015-03-01

    Full Text Available One titrimetric and two spectrophotometric methods are proposed for the determination of diethylcarbamazine citrate (DEC in bulk drug and in formulations using potassium iodate and potassium iodide as reagent. The methods employ the well-known analytical reaction between iodate and iodide in the presence of acid. In titrimetry (method A, the drug was treated with a measured excess of thiosulfate in the presence of unmeasured excess of iodate-iodide mixture and after a standing time of 10 min, the surplus thiosulfate was determined by back titration with iodine towards starch end point. Titrimetric assay is based on a 1:3 reaction stoichiometry between DEC and iodine and the method is applicable over 2.0-10.0 mg range. The liberated iodine is measured spectrophotometrically at 370 nm (method B or the iodine-starch complex measured at 570 nm (method C. In both methods, the absorbance is found to be linearly dependent on the concentration of iodine, which in turn is related to DEC concentration. The calibration curves are linear over 2.5-50 and 2.5-30 µg mL-1 DEC for method B and method C, respectively. The calculated molar absorptivity and Sandell sensitivity values were 6.48×103 L mol-1 cm-1 and 0.0604 µg cm-2, respectively, for method B, and their respective values for method C are 9.96×103 L mol-1 cm-1 and 0.0393 µg cm-2. The intra-day and inter-day accuracy and precision studies were carried out according to the ICH guidelines. The methods were successfully applied to the analysis of DEC formulations.

  4. Halogen-Bond-Promoted Photoactivation of Perfluoroalkyl Iodides: A Photochemical Protocol for Perfluoroalkylation Reactions.

    Science.gov (United States)

    Wang, Yaxin; Wang, Junhua; Li, Guo-Xing; He, Gang; Chen, Gong

    2017-03-17

    A new protocol for photochemical perfluoroalkylation reactions using perfluoroalkyl iodide, amine additive, and THF solvent is reported. This protocol does not require a photoredox catalyst and proceeds at ambient temperature with irradiation from a compact fluorescent lamp, low-intensity UV lamp, or sunlight. This protocol can be applied to the synthesis of perfluoroalkyl-substituted phenanthridines as well as effect the iodo-perfluoroalkylation of alkenes/alkynes and the C-H perfluoroalkylation of electron-rich arenes and heteroarenes. This C-H perfluoroalkylation reaction offers a unique method for site-selective labeling of oligopeptides at the tryptophan residue.

  5. Atypical cutaneous sporotrichosis in an immunocompetent adult: Response to potassium iodide

    Directory of Open Access Journals (Sweden)

    Nikita Gandhi

    2016-01-01

    Full Text Available Cutaneous sporotrichosis, also known as “Rose Gardener's disease,” caused by dimorphic fungus Sporothrix schenkii, is usually characterized by indolent nodular or nodulo-ulcerative lesions arranged in a linear pattern. We report bizarre nonlinear presentation of Sporotrichosis, in an immunocompetent adult occurring after a visit to Amazon rain forest, speculating infection with more virulent species of Sporothrix. The diagnosis was reached with the help of periodic acid-Schiff positive yeast cells and cigar shaped bodies seen in skin biopsy along with the therapeutic response to potassium iodide.

  6. Characteristics of the iodide/triiodide redox mediator in dye-sensitized solar cells.

    Science.gov (United States)

    Boschloo, Gerrit; Hagfeldt, Anders

    2009-11-17

    Dye-sensitized solar cells (DSCs) have gained widespread interest because of their potential for low-cost solar energy conversion. Currently, the certified record efficiency of these solar cells is 11.1%, and measurements of their durability and stability suggest lifetimes exceeding 10 years under operational conditions. The DSC is a photoelectrochemical system: a monolayer of sensitizing dye is adsorbed onto a mesoporous TiO(2) electrode, and the electrode is sandwiched together with a counter electrode. An electrolyte containing a redox couple fills the gap between the electrodes. The redox couple is a key component of the DSC. The reduced part of the couple regenerates the photo-oxidized dye. The formed oxidized species diffuses to the counter electrode, where it is reduced. The photovoltage of the device depends on the redox couple because it sets the electrochemical potential at the counter electrode. The redox couple also affects the electrochemical potential of the TiO(2) electrode through the recombination kinetics between electrons in TiO(2) and oxidized redox species. This Account focuses on the special properties of the iodide/triiodide (I(-)/I(3)(-)) redox couple in dye-sensitized solar cells. It has been the preferred redox couple since the beginning of DSC development and still yields the most stable and efficient DSCs. Overall, the iodide/triiodide couple has good solubility, does not absorb too much light, has a suitable redox potential, and provides rapid dye regeneration. But what distinguishes I(-)/I(3)(-) from most redox mediators is the very slow recombination kinetics between electrons in TiO(2) and the oxidized part of the redox couple, triiodide. Certain dyes adsorbed at TiO(2) catalyze this recombination reaction, presumably by binding iodine or triiodide. The standard potential of the iodide/triiodide redox couple is 0.35 V (versus the normal hydrogen electrode, NHE), and the oxidation potential of the standard DSC-sensitizer (Ru(dcbpy)(2

  7. Towards Renewable Iodide Sources for Electrolytes in Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Iryna Sagaidak

    2016-03-01

    Full Text Available A novel family of iodide salts and ionic liquids based on different carbohydrate core units is herein described for application in dye-sensitized solar cell (DSC. The influence of the molecular skeleton and the cationic structure on the electrolyte properties, device performance and on interfacial charge transfer has been investigated. In combination with the C106 polypyridyl ruthenium sensitizer, power conversion efficiencies lying between 5.0% and 7.3% under standard Air Mass (A.M. 1.5G conditions were obtained in association with a low volatile methoxypropionitrile (MPN-based electrolyte.

  8. Hydrothermal synthesis and solid-state structures of polynuclear technetium iodide compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kerlin, William M.; Poineau, Frederic; Forster, Paul M.; Czerwinski, Kenneth R.; Sattelberger, Alfred P.

    2015-01-01

    Two new technetium iodide compounds, Tc-2(O2CCH3)(4)I and K[Tc-8(mu-I)(8)I-4] I, were synthesized in an autoclave from the reaction of KTcO4 in glacial acetic acid with hydroiodic acid and/or alkali metal iodide salts at 210 degrees C under 60-70 atm hydrogen pressure. The structures of Tc-2(O2CCH3)(4)I and K[Tc-8(mu-I)(8)I-4] I were solved by single-crystal X-ray diffraction. The compound Tc-2(O2CCH3)(4)I crystallizes in the monoclinic space group C2/m with a = 7.1194(6) angstrom, b = 14.5851(13) angstrom, c = 7.1586(6) angstrom, and beta = 110.9540(10)degrees. The structure of Tc-2(O2CCH3)(4)I consists of infinite chains of Tc-2(O2CCH3)(4)(+) units linked by bridging iodides, an arrangement similar to the one found in Tc-2(O2CCH3)(4)X (X = Cl, Br). The TcATc separation in Tc-2 (O2CCH3)(4)I (i.e., 2.1146(4) angstrom) is consistent with the presence of a TcATc bond of order 3.5. Magnetic susceptibility measurements reveal Tc-2(O2CCH3)(4)I to be paramagnetic (mu(eff) = 1.84 B.M.) and support the electronic configuration sigma(2)pi(2)delta(2)delta*(1) for the Tc-2(5+) unit in the compound. The compound K[Tc-8(mu-I)(8)I-4]I crystallizes in the monoclinic space group P2(1)/n with a = 8.0018(5) angstrom, b = 14.5125(10) angstrom, c = 13.1948(9) angstrom, and beta = 102.3090(10) degrees, and is the first octanuclear technetium iodide cluster to be reported. The Tc-Tc separations in the [Tc-8(mu-I)(8)I-4] cluster (i.e., 2.164(3) angstrom, 2.5308(8) angstrom and 2.72(3) angstrom suggest the presence of Tc equivalent to Tc triple bonds, Tc=Tc double bonds and Tc-Tc single bonds.

  9. Effects of Aromatic Ammoniums on Methyl Ammonium Lead Iodide Hybrid Perovskite Materials

    Directory of Open Access Journals (Sweden)

    Jianli Yang

    2017-01-01

    Full Text Available The introduction of bulky ammoniums into methyl ammonium lead iodide hybrid perovskites (MAPbI3 has emerged as a promising strategy to improve the properties of these materials. In the present work, we studied the effects of several aromatic ammoniums onto the structural, electronic, and optical properties of MAPbI3. Although powder XRD data suggest that the bulky cations are not involved in the bulk phase of the MAPbI3, a surprisingly large effect of the bulky cations onto the photoluminescence properties was observed.

  10. Crystal Growth and Dissolution of Methylammonium Lead Iodide Perovskite in Sequential Deposition: Correlation between Morphology Evolution and Photovoltaic Performance.

    Science.gov (United States)

    Hsieh, Tsung-Yu; Huang, Chi-Kai; Su, Tzu-Sen; Hong, Cheng-You; Wei, Tzu-Chien

    2017-03-15

    Crystal morphology and structure are important for improving the organic-inorganic lead halide perovskite semiconductor property in optoelectronic, electronic, and photovoltaic devices. In particular, crystal growth and dissolution are two major phenomena in determining the morphology of methylammonium lead iodide perovskite in the sequential deposition method for fabricating a perovskite solar cell. In this report, the effect of immersion time in the second step, i.e., methlyammonium iodide immersion in the morphological, structural, optical, and photovoltaic evolution, is extensively investigated. Supported by experimental evidence, a five-staged, time-dependent evolution of the morphology of methylammonium lead iodide perovskite crystals is established and is well connected to the photovoltaic performance. This result is beneficial for engineering optimal time for methylammonium iodide immersion and converging the solar cell performance in the sequential deposition route. Meanwhile, our result suggests that large, well-faceted methylammonium lead iodide perovskite single crystal may be incubated by solution process. This offers a low cost route for synthesizing perovskite single crystal.

  11. Development of a screening approach to detect thyroid disrupting chemicals that inhibit the human sodium iodide symporter (NIS).

    Science.gov (United States)

    Hallinger, Daniel R; Murr, Ashley S; Buckalew, Angela R; Simmons, Steven O; Stoker, Tammy E; Laws, Susan C

    2017-04-01

    The U.S. EPA's Endocrine Disruptor Screening Program aims to use high-throughput assays and computational toxicology models to screen and prioritize chemicals that may disrupt the thyroid signaling pathway. Thyroid hormone biosynthesis requires active iodide uptake mediated by the sodium/iodide symporter (NIS). Monovalent anions, such as the environmental contaminant perchlorate, are competitive inhibitors of NIS, yet limited information exists for more structurally diverse chemicals. A novel cell line expressing human NIS, hNIS-HEK293T-EPA, was used in a radioactive iodide uptake (RAIU) assay to identify inhibitors of NIS-mediated iodide uptake. The RAIU assay was optimized and performance evaluated with 12 reference chemicals comprising known NIS inhibitors and inactive compounds. An additional 39 chemicals including environmental contaminants were evaluated, with 28 inhibiting RAIU over 20% of that observed for solvent controls. Cell viability assays were performed to assess any confounding effects of cytotoxicity. RAIU and cytotoxic responses were used to calculate selectivity scores to group chemicals based on their potential to affect NIS. RAIU IC50 values were also determined for chemicals that displayed concentration-dependent inhibition of RAIU (≥50%) without cytotoxicity. Strong assay performance and highly reproducible results support the utilization of this approach to screen large chemical libraries for inhibitors of NIS-mediated iodide uptake. Published by Elsevier Ltd.

  12. Elucidating the effect of the lead iodide complexation degree behind the morphology and performance of perovskite solar cells.

    Science.gov (United States)

    Mastria, R; Colella, S; Qualtieri, A; Listorti, A; Gigli, G; Rizzo, A

    2017-03-17

    The inclusion of iodide additives in hybrid perovskite precursor solutions has been successfully exploited to improve the solar cell efficiency but their impact on perovskite formation, morphology and photovoltaic performance is still not clear. Here an extensive analysis of the effect of iodide additives in the solution-phase and during the perovskite film formation, as well as their effect on device performance is provided. The results demonstrate that in the solution-phase the additives promote the formation of lead poly-iodide species resulting in the disaggregation of the inorganic lead iodide framework and in the formation of smaller nuclei inducing the growth of uniform and smooth perovskite films. Most importantly, the complexation capability of different iodide additives does not only directly affect film morphology but also influences the density of defect states by varying the stoichiometry of precursors. These findings demonstrate that the fine control of the interactions of the chemical species in the solution-phase is essential for the precise control of the morphology at the nanoscale and the growth of the perovskite films with a reduced density of defect states. Therefore, the in-depth understanding of all the processes involved in the solution-phase is the first step for the development of a facile and reproducible approach for the fabrication of hybrid perovskite solar cells with enhanced photovoltaic performance.

  13. Luminescent europium and terbium complexes of dipyridoquinoxaline and dipyridophenazine ligands as photosensitizing antennae: structures and biological perspectives.

    Science.gov (United States)

    Dasari, Srikanth; Patra, Ashis K

    2015-12-14

    The europium(III) and terbium(III) complexes, namely [Eu(dpq)(DMF)2(NO3)3] (1), [Eu(dppz)2(NO3)3] (2), [Tb(dpq)(DMF)2Cl3] (3), and [Tb(dppz)(DMF)2Cl3] (4), where dipyrido[3,2-d:2',3'-f]quinoxaline (dpq in 1 and 3), dipyrido[3,2-a:2',3'-c]phenazine (dppz in 2 and 4) and N,N'-dimethylformamide (DMF) have been isolated, characterized from their physicochemical data, luminescence studies and their interaction with DNA, serum albumin protein and photo-induced DNA cleavage activity are studied. The X-ray crystal structures of complexes 1-4 show discrete mononuclear Ln(3+)-based structures. The Eu(3+) in [Eu(dpq)(DMF)2(NO3)3] (1) and [Eu(dppz)2(NO3)3] (2) as [Eu(dppz)2(NO3)3]·dppz (2a) adopts a ten-coordinated bicapped dodecahedron structure with a bidentate N,N-donor dpq ligand, two DMF and three NO3(-) anions in 1 and two bidentate N,N-donor dppz ligands and three NO3(-) anions in 2. Complexes 3 and 4 show a seven-coordinated mono-capped octahedron structure where Tb(3+) contains bidentate dpq/dppz ligands, two DMF and three Cl(-) anions. The complexes are highly luminescent in nature indicating efficient photo-excited energy transfer from the dpq/dppz antenna to Ln(3+) to generate long-lived emissive excited states for characteristic f → f transitions. The time-resolved luminescence spectra of complexes 1-4 show typical narrow emission bands attributed to the (5)D0 → (7)F(J) and (5)D4 → (7)F(J) f-f transitions of Eu(3+) and Tb(3+) ions respectively. The number of inner-sphere water molecules (q) was determined from luminescence lifetime measurements in H2O and D2O confirming ligand-exchange reactions with water in solution. The complexes display significant binding propensity to the CT-DNA giving binding constant values in the range of 1.0 × 10(4)-6.1 × 10(4) M(-1) in the order 2, 4 (dppz) > 1, 3 (dpq). DNA binding data suggest DNA groove binding with the partial intercalation nature of the complexes. All the complexes also show binding propensity (K(BSA)

  14. Colorimetric Solid Phase Extraction for the Measurement of Total I (Iodine, Iodide, and Triiodide) in Spacecraft Drinking Water

    Science.gov (United States)

    Lipert, Robert J.; Porter, Marc D.; Siperko, Lorraine M.; Gazda, Daniel B.; Rutz, Jeff A.; Schultz, John R.; Carrizales, Stephanie M.; McCoy, J. Torin

    2009-01-01

    An experimental drinking water monitoring kit for the measurement of iodine and silver(I) was recently delivered to the International Space Station (ISS). The kit is based on Colorimetric Solid Phase Extraction (CSPE) technology, which measures the change in diffuse reflectance of indicator disks following exposure to a water sample. To satisfy additional spacecraft water monitoring requirements, CSPE has now been extended to encompass the measurement of total I (iodine, iodide, and triiodide) through the introduction of an oxidizing agent, which converts iodide and triiodide to iodine, for measurement using the same indicator disks currently being tested on ISS. These disks detect iodine, but are insensitive to iodide and triiodide. We report here the operational considerations, design, and ground-based performance of the CSPE method for total I. The results demonstrate that CSPE technology is poised to meet NASA's total I monitoring requirements.

  15. Potentiation of antimicrobial photodynamic inactivation mediated by a cationic fullerene by added iodide: in vitro and in vivo studies.

    Science.gov (United States)

    Zhang, Yunsong; Dai, Tianhong; Wang, Min; Vecchio, Daniela; Chiang, Long Y; Hamblin, Michael R

    2015-03-01

    Antimicrobial photodynamic inactivation with fullerenes bearing cationic charges may overcome resistant microbes. We synthesized C60-fullerene (LC16) bearing decaquaternary chain and deca-tertiary-amino groups that facilitates electron-transfer reactions via the photoexcited fullerene. Addition of the harmless salt, potassium iodide (10 mM) potentiated the ultraviolet A (UVA) or white light-mediated killing of Gram-negative bacteria Acinetobacter baumannii, Gram-positive methicillin-resistant Staphylococcus aureus and fungal yeast Candida albicans by 1-2+ logs. Mouse model infected with bioluminescent Acinetobacter baumannii gave increased loss of bioluminescence when iodide (10 mM) was combined with LC16 and UVA/white light. The mechanism may involve photoinduced electron reduction of (1)(C60>)* or (3)(C60>)* by iodide producing I· or I2 followed by subsequent intermolecular electron-transfer events of (C60>)-· to produce reactive radicals.

  16. The effect of potassium iodide on the production of acid phosphatase by Sporothrix schenckii

    Directory of Open Access Journals (Sweden)

    P. S. Grover

    2003-06-01

    Full Text Available The present study was undertaken to find out the in vitro effect of potassium iodide (KI on the production of acid phosphatase by fully characterized strain of S.schenckii isolated from a patient of Cutaneous Sporotrichosis. The enzyme acid phosphatase was estimated during the 3 phases of growth of S.schenckii, without and with three concentrations of KI incorporated in the culture medium. In the control and in the test proper, with various concentrations of KI, no adverse effect of KI was observed on the production of acid phosphatase in early and mid log phase of fungal growth. Whereas in the exponential phase in test proper, there was a statistical significant decrease in the enzyme production with 0.8% and 3.2% of KI. The low activity at 0.8% and 3.2% KI indicates that KI has inhibitory effect on the growth of S.schenckii and has led to decrease in the activity of the enzyme. (Med J Indones 2003; 12: 65-8 Keywords: S.schenckii, acid phosphatase, potassium iodide

  17. A study of the homogeneity and deviations from stoichiometry in mercuric iodide

    Energy Technology Data Exchange (ETDEWEB)

    Burger, A.; Morgan, S.; He, C.; Silberman, E.; van den Berg, L.; Ortale, C.; Franks, L.; Schieber, M.

    1989-01-01

    We have been able to determine the deviations from stoichiometry of mercuric iodide (HgI/sub 2/) by using Differential Scanning Calorimetry (DSC). Mercury excess or iodine deficiency in mercuric iodide can be evaluated from the eutectic melting of HgI/sub 2/-- Hg/sub 2/I/sub 2/ at 235/degree/C which appears as an additional peak in DSC thermograms. I/sub 2/ excess can be found from the existence of the I/sub 2/--HgI/sub 2/ eutectic melting at 103/degree/C. An additional DSC peak appears in some samples around 112/degree/C that could be explained by the presence of iodine inclusions. Using Resonance Fluorescence Spectroscopy (RFS) we have been able to determine the presence of free I/sub 2/ that is released by samples during the heating at 120/degree/C (crystal growth temperature) thus giving additional support to the above DSC results. 19 refs., 6 figs., 2 tabs.

  18. Photocatalytic hydrogen generation from hydriodic acid using methylammonium lead iodide in dynamic equilibrium with aqueous solution

    Science.gov (United States)

    Park, Sunghak; Chang, Woo Je; Lee, Chan Woo; Park, Sangbaek; Ahn, Hyo-Yong; Nam, Ki Tae

    2017-01-01

    The solar-driven splitting of hydrohalic acids (HX) is an important and fast growing research direction for H2 production. In addition to the hydrogen, the resulting chemicals (X2/X3-) can be used to propagate a continuous process in a closed cycle and are themselves useful products. Here we present a strategy for photocatalytic hydrogen iodide (HI) splitting using methylammonium lead iodide (MAPbI3) in an effort to develop a cost-effective and easily scalable process. Considering that MAPbI3 is a water-soluble ionic compound, we exploit the dynamic equilibrium of the dissolution and precipitation of MAPbI3 in saturated aqueous solutions. The I- and H+ concentrations of the aqueous solution are determined to be the critical parameters for the stabilization of the tetragonal MAPbI3 phase. Stable and efficient H2 production under visible light irradiation was demonstrated. The solar HI splitting efficiency of MAPbI3 was 0.81% when using Pt as a cocatalyst.

  19. Non-triiodide based autoinhibition by iodide ion in the trithionate-iodine reaction.

    Science.gov (United States)

    Cseko, György; Horváth, Attila K

    2010-06-17

    The trithionate-iodine reaction has been studied spectrophotometrically in a slightly acidic medium at 25.0 +/- 0.1 degrees C in acetate/acetic acid buffer monitoring the absorbance at 468 nm at the isosbestic point of the iodine-triiodide ion system in the absence and presence of initially added iodide ion at I = 0.5 M ionic strength adjusted by sodium perchlorate. The stoichiometry of the reaction was found to be S(3)O(6)(2-) + 4I(2) + 6H(2)O --> 3SO(4)(2-) + 8I(-) + 12H(+). It is also shown that the consumption of iodine is inhibited by iodide ion, but it cannot be simply explained via the fast equilibrium formation of triiodide ion. A five-step kinetic model with four fitted and fixed kinetic parameters is proposed and discussed in detail, on the basis of which all the most important characteristics of the measured kinetic curves are adequately explained.

  20. Solution- and solid-phase oligosaccharide synthesis using glucosyl iodides: a comparative study.

    Science.gov (United States)

    Lam, Son N; Gervay-Hague, Jacquelyn

    2002-11-19

    Glycosyl iodide donors have been used in both solid- and solution-phase syntheses yielding alpha-(1 --> 6)-linked glucosyl oligomers in highly efficient protocols. While the solid-phase strategy offers advantages in terms of ease of purification, it requires a total of 7.5 equiv of donor and approximately 12 h to complete the incorporation of one monosaccharide unit. In contrast, solution-phase methods require only 2.5 equiv of donor and 2-3 h reaction time per glycosylation. Moreover, since the reactions are virtually quantitative (> 90%) column chromatography of the material is facile. The overall advantages of solution-phase oligosaccharide synthesis were further illustrated in the convergent synthesis of a hexamer (methoxycarbonylmethyl 6-O-acetyl-2,3,4-tri-O-benzyl-alpha-D-glucopyranosyl-(1 --> 6)-tetrakis-(2,3,4-tri-O-benzyl-alpha-D-glucopyranosyl-(1 --> 6))-2,3,4-tri-O-benzyl-1-thio-alpha-D-glucopyranoside) that was constructed from dimer donor iodides in a two-plus-two and a two-plus-four fashion. Copyright 2002 Elsevier Science Ltd.

  1. Functionalized metal organic frameworks for effective capture of radioactive organic iodides

    KAUST Repository

    Li, Baiyan

    2017-06-27

    Highly efficient capture of radioactive organic iodides (ROIs) from off-gas mixtures remains a substantial challenge for nuclear waste treatment. Current materials utilized for ROI sequestration suffer from low capacity, high cost (e.g. use of noble metals), and poor recyclability. Recently, we have developed a new strategy to tackle this challenge by functionalizing MOF materials with tertiary amines to create molecular traps for the effective capture and removal of ROIs (e.g. radioactive methyl iodide) from nuclear wastes. To further enhance the uptake capacity and performance of CH3I capture by ROI molecular traps, herein, we carry out a systematic study to investigate the effect of different amine molecules on ROI capture. The results demonstrate a record-high CH3I saturation uptake capacity of 80% for MIL-101-Cr-DMEDA at 150 °C, which is 5.3 times that of Ag0@MOR (15 wt%), a leading adsorbent material for capturing ROIs during nuclear fuel reprocessing. Furthermore, the CH3I decontamination factors (DFs) for MIL-101-Cr-DMEDA are as high as 5000 under simulated reprocessing conditions, largely exceeding that of facility regulatory requirements (DF = 3000). In addition, MIL-101-Cr-DMEDA can be recycled without loss of capacity, illustrating yet another advantage compared to known industrial adsorbents, which are typically of a

  2. Flow cytometric determination of basophils in whole blood with n-propyl Astra Blue iodide.

    Science.gov (United States)

    Malin, M J; Hwang, D R; Ben-David, D

    1986-07-01

    Within the past year, it has become apparent, in connection with its use on automatic flow cytometers, that the quality of commercially available Alcian Blue has significantly declined. A homologous series of alkylated (C1-C7) Astra Blue quaternary ammonium halides was prepared, characterized, and evaluated for the detection of basophils in whole blood. On the Technicon H6000 flow cytometer, the resolution of the basophil cluster from the main population of unstained white blood cells was found to depend on the chain length of the quaternizing alkyl group. Optimal basophil resolution was observed for the n-propyl derivative. Correlation of the new method vs Alcian Blue as the reference on the H6000 was expressed as follows: %Baso (Astra Blue) = 0.89% Baso (Alcian Blue) + 0.12% for 180 fresh whole blood samples. Within-run precision at a basophil differential count of 0.73% was characterized by SD = 0.11, identical to that obtained for Alcian Blue. Aqueous solutions of n-propyl Astra Blue iodide, in contrast to Alcian Blue, are thermally stable. Heating the reagent for 1 h at 100 degrees C did not alter solubility or cytochemical behavior. In contrast, parallel treatment of Alcian Blue yielded insoluble material by hydrolysis of the isothiouronium groups. The reagent for basophil detection comprises n-propyl Astra Blue iodide, lanthanum chloride, sodium chloride, Tween 20, and cetylpyridinium chloride. The Astra Blue derivatives were characterized by uv-vis, ir, percentage halide, paper chromatography, and 13C NMR.

  3. Safe disposal of radioactive iodide ions from solutions by Ag2O grafted sodium niobate nanofibers.

    Science.gov (United States)

    Mu, Wanjun; Li, Xingliang; Liu, Guoping; Yu, Qianhong; Xie, Xiang; Wei, Hongyuan; Jian, Yuan

    2016-01-14

    Radioactive iodine isotopes are released into the environment by the nuclear industry and medical research institutions using radioactive materials, and have negative effects on organisms living within the ecosystem. Thus, safe disposal of radioactive iodine is necessary and crucial. For this reason, the uptake of iodide ions was investigated in Ag2O nanocrystal grafted sodium niobate nanofibers, which were prepared by forming a well-matched phase coherent interface between them. The resulting composite was applied as an efficient adsorbent for I(-) anions by forming an AgI precipitate, which also remained firmly attached to the substrates. Due to their one-dimensional morphology, the new adsorbents can be easily dispersed in liquids and readily separated after purification. This significantly enhances the adsorption efficiency and reduces the separation costs. The change in structure from the pristine sodium niobate to Ag2O anchored sodium niobate and to the used adsorbent was examined by using various characterization techniques. The effects of Ag(+) concentration, pH, equilibration time, ionic strength and competing ions on the iodide ion removal ability of the composite were studied. The Ag2O nanocrystal grafted sodium niobate adsorbent showed a high adsorption capacity and excellent selectivity for I(-) anions in basic solutions. Our results are useful for the further development of improved adsorbents for removing I(-) anions from basic wastewater.

  4. Chitosan finishing nonwoven textiles loaded with silver and iodide for antibacterial wound dressing applications.

    Science.gov (United States)

    Aubert-Viard, François; Martin, Adeline; Chai, Feng; Neut, Christel; Tabary, Nicolas; Martel, Bernard; Blanchemain, Nicolas

    2015-03-02

    Polyethylene terephtalate (PET) and Polypropylene (PP) textiles are widely used in biomedical application such as wound dressings and implants. The aim of this work was to develop an antibacterial chitosan (CHT) coating activated by silver or by iodine. Chitosan was immobilized onto PET and PP supports using citric acid (CTR) as a crosslinking agent through a pad-dry-cure textile finishing process. Interestingly, depending on the CHT/CTR molar ratio, two different systems were obtained: rich in cationic ammonium groups when the CTR concentration was 1%w/v, and rich in anionic carboxylate groups when the CTR concentration was 10%w/v. As a consequence, such samples could be selectively loaded with iodine and silver nitrate, respectively.Both types of coatings were analyzed using SEM and FTIR, their sorption capacities were evaluated toward iodide/iodate anions (I(-)/IO3(-)) and the silver cations (Ag(+)) were evaluated using elemental analysis. Finally, in vitro evaluations were carried out to evaluate the cytocompatibility on the epithelial cell line. The silver loaded textile reported a stronger antibacterial effect against E.coli (5 log10 reduction) than toward S. aureus (3 log10) while the antibacterial effect of the iodide loaded textiles was limited to 1 log10 to 2 log10 on both strains.

  5. Gas-phase pesticide measurement using iodide ionization time-of-flight mass spectrometry

    Directory of Open Access Journals (Sweden)

    T. Murschell

    2017-06-01

    Full Text Available Volatilization and subsequent processing in the atmosphere are an important environmental pathway for the transport and chemical fate of pesticides. However, these processes remain a particularly poorly understood component of pesticide lifecycles due to analytical challenges in measuring pesticides in the atmosphere. Most pesticide measurements require long (hours to days sampling times coupled with offline analysis, inhibiting observation of meteorologically driven events or investigation of rapid oxidation chemistry. Here, we present chemical ionization time-of-flight mass spectrometry with iodide reagent ions as a fast and sensitive measurement of four current-use pesticides. These semi-volatile pesticides were calibrated with injections of solutions onto a filter and subsequently volatilized to generate gas-phase analytes. Trifluralin and atrazine are detected as iodide–molecule adducts, while permethrin and metolachlor are detected as adducts between iodide and fragments of the parent analyte molecule. Limits of detection (1 s are 0.37, 0.67, 0.56, and 1.1 µg m−3 for gas-phase trifluralin, metolachlor, atrazine, and permethrin, respectively. The sensitivities of trifluralin and metolachlor depend on relative humidity, changing as much as 70 and 59, respectively, as relative humidity of the sample air varies from 0 to 80 %. This measurement approach is thus appropriate for laboratory experiments and potentially near-source field measurements.

  6. (E)-1-Methyl-4-[2-(2-naphth-yl)vin-yl]pyridinium iodide.

    Science.gov (United States)

    Fun, Hoong-Kun; Chanawanno, Kullapa; Chantrapromma, Suchada

    2009-05-29

    In the title compound, C(18)H(16)N(+)·I(-), the cation is disordered over two orientations related by a 180° rotation about its long axis with occupancies of 0.554 (7) and 0.446 (7). Both disorder components exist in an E configuration. The dihedral angle between the pyridinium ring and the naphthalene ring system is 4.7 (6)° in the major disorder component and 1.6 (8)° in the minor component. In the crystal structure, centrosymmetrically related cations are stacked along the a axis, with significant π-π inter-actions between the pyridinium ring and the naphthalene ring system [centroid-centroid distance = 3.442 (9) Å]. The iodide ions are located between adjacent columns of cations. The cations are linked to the iodide ions by C-H⋯I inter-actions. Weak C-H⋯π inter-actions involving the methyl group are also observed.

  7. First-Principles Identification of Iodine Exchange Mechanism in Iodide Ionic Liquid.

    Science.gov (United States)

    Thapa, Ranjit; Park, Noejung

    2012-10-18

    We investigated the microscopic mechanism of ion transport in iodide ionic liquid, using first-principles calculations. We show that the desorption barrier of polyiodides (I3(-) or I5(-)) from the cation is in a similar energy range as or higher than the barrier for the bond dissociation and ensued desorption of neutral iodine (I2). This suggests that, instead of the physical diffusion of such a negatively charged multiatomic species, the exchange of neutral iodine (I2) between the polyiodides can be an easier channel for the movement of polyiodide. For the transport of the monoiodide anion (I(-)), we suggest the contribution of the Grotthuss-type ion exchange through the intermediately formed even-member anion (I2n(-)), in addition to drift and diffusion. As a result, we suggest that, instead of the commonly cited diffusion of the triiodide/iodide (I3(-)/I(-)) redox couple, the exchange of neutral iodine (I2) and the Grotthuss-type transport (I(-)) constitute the dominant ion transport mechanism.

  8. Observation of crystallization and characterizations on thiourea cadmium iodide: A semi-organic optical material

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Preeti; Hasmuddin, Mohd. [Crystal Growth and XRD Lab, Department of Physics, Jamia Millia Islamia, New Delhi 110025 (India); Abdullah, M.M. [Crystal Growth and XRD Lab, Department of Physics, Jamia Millia Islamia, New Delhi 110025 (India); Promising Centre for Sensors and Electronic Devices (PCSED), Department of Physics, Faculty of Sciences and Arts, Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia); Shkir, Mohd. [Crystal Growth and XRD Lab, Department of Physics, Jamia Millia Islamia, New Delhi 110025 (India) and Department of Physics, ARSD College, University of Delhi, New Delhi 110021 (India); Wahab, M.A., E-mail: aries.pre84@gmail.com [Crystal Growth and XRD Lab, Department of Physics, Jamia Millia Islamia, New Delhi 110025 (India)

    2013-10-15

    Graphical abstract: - Highlights: • Thiourea cadmium iodide (TCI) was grown by slow evaporation solution technique. • Morphology and growth rate of the grown compound are determined with the help of inverted microscope. • Optical band gap has been determined. • Microstructure analysis has been reported. • Electrical study has been reported and discussed. - Abstract: In this work, the single crystals of thiourea cadmium iodide were grown by slow evaporation solution technique in two different ratios 2:1 and 1:1. During the formation of their single crystals the morphological features and its live growth process were recorded with the help of inverted microscope. Structural studies of the grown crystals have been carried out by powder X-ray diffraction to confirm the crystal system and vibrational modes by Raman spectroscopy. The optical energy band gaps were investigated through UV–vis spectroscopy study. The surface morphology of the grown single crystals was analyzed by using Scanning Electron Microscope and thermal analysis was carried out by using thermogravimetric analysis. The electrical properties were also studied as a function of frequency and the obtained results are discussed.

  9. Analysis of perchlorate, thiocyanate, nitrate and iodide in human amniotic fluid using ion chromatography and electrospray tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Blount, Benjamin C. [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States)]. E-mail: bblount@cdc.gov; Valentin-Blasini, Liza [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States)

    2006-05-10

    Because of health concerns surrounding in utero exposure to perchlorate, we developed a sensitive and selective method for quantifying iodide, as well as perchlorate and other sodium-iodide symporter (NIS) inhibitors in human amniotic fluid using ion chromatography coupled with electrospray ionization tandem mass spectrometry. Iodide and NIS inhibitors were quantified using a stable isotope-labeled internal standards (Cl{sup 18}O{sub 4} {sup -}, S{sup 13}CN{sup -} and {sup 15}NO{sub 3} {sup -} with excellent assay accuracy of 100%, 98%, 99%, 95% for perchlorate, thiocyanate, nitrate and iodide, respectively, in triplicate analysis of spiked amniotic fluid sample). Excellent analytical precision (<5.2% RSD for all analytes) was found when amniotic fluid quality control pools were repetitively analyzed for iodide and NIS-inhibitors. Selective chromatography and tandem mass spectrometry reduced the need for sample cleanup, resulting in a rugged and rapid method capable of routinely analyzing 75 samples/day. Analytical response was linear across the physiologically relevant concentration range for the analytes. Analysis of a set of 48 amniotic fluid samples identified the range and median levels for perchlorate (0.057-0.71, 0.18 {mu}g/L), thiocyanate (<10-5860, 89 {mu}g/L), nitrate (650-8900, 1620 {mu}g/L) and iodide (1.7-170, 8.1 {mu}g/L). This selective, sensitive, and rapid method will help assess exposure of the developing fetus to low levels of NIS-inhibitors and their potential to inhibit thyroid function.

  10. Analysis of heterogeneous water vapor uptake by metal iodide cluster ions via differential mobility analysis-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Oberreit, Derek [Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Fluid Measurement Technologies, Inc., Saint Paul, Minnesota 55110 (United States); Rawat, Vivek K.; Larriba-Andaluz, Carlos; Ouyang, Hui; McMurry, Peter H.; Hogan, Christopher J., E-mail: hogan108@umn.edu [Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2015-09-14

    The sorption of vapor molecules onto pre-existing nanometer sized clusters is of importance in understanding particle formation and growth in gas phase environments and devising gas phase separation schemes. Here, we apply a differential mobility analyzer-mass spectrometer based approach to observe directly the sorption of vapor molecules onto iodide cluster ions of the form (MI){sub x}M{sup +} (x = 1-13, M = Na, K, Rb, or Cs) in air at 300 K and with water saturation ratios in the 0.01-0.64 range. The extent of vapor sorption is quantified in measurements by the shift in collision cross section (CCS) for each ion. We find that CCS measurements are sensitive enough to detect the transient binding of several vapor molecules to clusters, which shift CCSs by only several percent. At the same time, for the highest saturation ratios examined, we observed CCS shifts of up to 45%. For x < 4, cesium, rubidium, and potassium iodide cluster ions are found to uptake water to a similar extent, while sodium iodide clusters uptake less water. For x ≥ 4, sodium iodide cluster ions uptake proportionally more water vapor than rubidium and potassium iodide cluster ions, while cesium iodide ions exhibit less uptake. Measured CCS shifts are compared to predictions based upon a Kelvin-Thomson-Raoult (KTR) model as well as a Langmuir adsorption model. We find that the Langmuir adsorption model can be fit well to measurements. Meanwhile, KTR predictions deviate from measurements, which suggests that the earliest stages of vapor uptake by nanometer scale species are not well described by the KTR model.

  11. Spin Waves in Terbium

    DEFF Research Database (Denmark)

    Jensen, J.; Houmann, Jens Christian Gylden

    1975-01-01

    The selection rules for the linear couplings between magnons and phonons propagating in the c direction of a simple basal-plane hcp ferromagnet are determined by general symmetry considerations. The acoustic-optical magnon-phonon interactions observed in the heavy-rare-earth metals have been expl...... by Liu. The coupled magnon—transverse-phonon system for the c direction of Tb is analyzed in detail, and the strengths of the couplings are deduced as a function of wave vector by combining the experimental studies with the theory....

  12. Spin Waves in Terbium

    DEFF Research Database (Denmark)

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

    1975-01-01

    The energies of spin waves propagating in the c direction of Tb have been studied by inelastic neutron scattering, as a function of a magnetic field applied along the easy and hard directions in the basal plane, and as a function of temperature. From a general spin Hamiltonian, consistent...... with the symmetry, we deduce the dispersion relation for the spin waves in a basal-plane ferromagnet. This phenomenological spin-wave theory accounts for the observed behavior of the magnon energies in Tb. The two q⃗-dependent Bogoliubov components of the magnon energies are derived from the experimental results...

  13. Inner Sphere and Outer Sphere Electron Transfer to Methyl Iodide. Deuterium and 13C Kinetic Isotope Effects

    DEFF Research Database (Denmark)

    Holm, Torkil; Crossland, Ingolf

    1996-01-01

    Deuterium and 13C kinetic isotope effects (KIEs) have been determined for the conversion of methyl iodide into methyl radical via inner sphere ET (electron transfer) and via outer sphere ET. The alfa-deuterium KIE was found to be very high for in...

  14. High-performance rechargeable lithium-iodine batteries using triiodide/iodide redox couples in an aqueous cathode.

    Science.gov (United States)

    Zhao, Yu; Wang, Lina; Byon, Hye Ryung

    2013-01-01

    Development of promising battery systems is being intensified to fulfil the needs of long-driving-ranged electric vehicles. The successful candidates for new generation batteries should have higher energy densities than those of currently used batteries and reasonable rechargeability. Here we report that aqueous lithium-iodine batteries based on the triiodide/iodide redox reaction show a high battery performance. By using iodine transformed to triiodide in an aqueous iodide, an aqueous cathode involving the triiodide/iodide redox reaction in a stable potential window avoiding water electrolysis is demonstrated for lithium-iodine batteries. The high solubility of triiodide/iodide redox couples results in an energy density of ~ 0.33 kWh kg(-1), approximately twice that of lithium-ion batteries. The reversible redox reaction without the formation of resistive solid products promotes rechargeability, demonstrating 100 cycles with negligible capacity fading. A low cost, non-flammable and heavy-metal-free aqueous cathode can contribute to the feasibility of scale-up of lithium-iodine batteries for practical energy storage.

  15. The Impact of Iodide-Mediated Ozone Deposition and Halogen Chemistry on Surface Ozone Concentrations Across the Continental United States

    Science.gov (United States)

    The air quality of many large coastal areas in the United States is affected by the confluence of polluted urban and relatively clean marine airmasses, each with distinct atmospheric chemistry. In this context, the role of iodide-mediated ozone (O3) deposition over seawater and m...

  16. The lactoperoxidase system : the influence of iodide and the chemical and antimicrobial stability over the period of about 18 months

    NARCIS (Netherlands)

    Bosch, EH; Van Doorne, H; De Vries, S

    The lactoperoxidase (LP) system is a natural antimicrobial system, the use of which has been suggested as a preservative in foods and pharmaceuticals. The effect of adding iodide to the LP system, the chemical stability and the change in antimicrobial effectiveness during storage was studied.

  17. Polymer adsorption and its effect on the Stability of hydrophobic colloids. III. Kinetics of th Flocculation of silver iodide sols

    NARCIS (Netherlands)

    Fleer, G.J.; Lyklema, J.

    1976-01-01

    In a previous study on the flocculation of silver iodide sols by polyvinyl alcohol (PVA) it was demonstrated that the extent of flocculation depends critically on the way in which sol particles and polymer are mixed. Optimal flocculation was shown to occur if a two-portion method of mixing is

  18. Perfluoroalkylation of Aryl-N,N-dimethyl Hydrazones Using Hypervalent Iodine(III) Reagents or Perfluoroalkyl Iodides.

    Science.gov (United States)

    Janhsen, Benjamin; Studer, Armido

    2017-11-17

    Radical trifluoromethylation of aryl N,N-dimethyl hydrazones using TBAI as an initiator and Togni's reagent as a trifluoromethyl radical source is described. Cascades proceed via electron-catalysis; this approach is generally more applicable to hydrazone perfluoroalkylation using perfluoroalkyl iodides as the radical precursors in combination with a base under visible-light initiation.

  19. 10 CFR 35.392 - Training for the oral administration of sodium iodide I-131 requiring a written directive in...

    Science.gov (United States)

    2010-01-01

    ... classroom and laboratory training, applicable to the medical use of sodium iodide I-131 for procedures...) Chemistry of byproduct material for medical use; and (v) Radiation biology; and (2) Has work experience... millicuries). 35.392 Section 35.392 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL...

  20. Congenital Hypothyroidism Caused by a PAX8 Gene Mutation Manifested as Sodium/Iodide Symporter Gene Defect

    Directory of Open Access Journals (Sweden)

    Wakako Jo

    2010-01-01

    Full Text Available Loss-of-function mutations of the PAX8 gene are considered to mainly cause congenital hypothyroidism (CH due to thyroid hypoplasia. However, some patients with PAX8 mutation have demonstrated a normal-sized thyroid gland. Here we report a CH patient caused by a PAX8 mutation, which manifested as iodide transport defect (ITD. Hypothyroidism was detected by neonatal screening and L-thyroxine replacement was started immediately. Although 123I scintigraphy at 5 years of age showed that the thyroid gland was in the normal position and of small size, his iodide trapping was low. The ratio of the saliva/plasma radioactive iodide was low. He did not have goiter; however laboratory findings suggested that he had partial ITD. Gene analyses showed that the sodium/iodide symporter (NIS gene was normal; instead, a mutation in the PAX8 gene causing R31H substitution was identified. The present report demonstrates that individuals with defective PAX8 can have partial ITD, and thus genetic analysis is useful for differential diagnosis.

  1. Evaluation of iodide deficiency in the lactating rat and pup using a biologically based dose response (BBDR) Model***

    Science.gov (United States)

    A biologically-based dose response (BBDR) model for the hypothalamic-pituitary thyroid (HPT) axis in the lactating rat and nursing pup was developed to describe the perturbations caused by iodide deficiency on the 1-IPT axis. Model calibrations, carried out by adjusting key model...

  2. Evaluation of iodide deficiency in the lactating rat and pup using a biologically based dose-response model

    Science.gov (United States)

    A biologically-based dose response (BBDR) model for the hypothalamic-pituitary thyroid (BPT) axis in the lactating rat and nursing pup was developed to describe the perturbations caused by iodide deficiency on the HPT axis. Model calibrations, carried out by adjusting key model p...

  3. Pd-Catalyzed Conversion of Aryl Iodides to Sulfonyl Fluorides Using SO2 Surrogate DABSO and Selectfluor.

    Science.gov (United States)

    Tribby, Ariana L; Rodríguez, Ismeraí; Shariffudin, Shamira; Ball, Nicholas D

    2017-02-17

    A one-pot Pd-catalyzed conversion of aryl iodide to aryl sulfonyl fluorides using DABSO and Selectfluor has been developed generating aryl sulfonyl fluorides in good to excellent yields. The reaction results in the generation of electronically and sterically diverse sulfonyl fluorides. Additionally, sulfonyl fluorides can be converted to aryl sulfonamides and sulfonic esters using Cs2CO3 under mild conditions.

  4. Preparation of glycosyl thiourea derivatives from glycosyl azides using sulfamic acid and sodium iodide in one-pot.

    Science.gov (United States)

    Gucchait, Arin; Jana, Manas; Jana, Kuladip; Misra, Anup Kumar

    2016-11-03

    Novel one-pot reaction conditions have been developed for the preparation of glycosyl thiourea derivatives directly from glycosyl azides mediated by a combination of sulfamic acid and sodium iodide. The reaction conditions were clean, non-toxic and the products were isolated in good to excellent yield. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-06-01

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

  6. Efficient organic solar cells using copper(I) iodide (CuI) hole transport layers

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Ying [Key Laboratory of Luminescence and Optical Information, Ministry of Education, Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing 100044 (China); Department of Physics and Centre for Plastic Electronics, Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom); Yaacobi-Gross, Nir; Perumal, Ajay K.; Faber, Hendrik A.; Bradley, Donal D. C.; Anthopoulos, Thomas D., E-mail: zhqhe@bjtu.edu.cn, E-mail: t.anthopoulos@imperial.ac.uk [Department of Physics and Centre for Plastic Electronics, Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom); Vourlias, George; Patsalas, Panos A. [Department of Physics, Laboratory of Applied Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki (Greece); He, Zhiqun, E-mail: zhqhe@bjtu.edu.cn, E-mail: t.anthopoulos@imperial.ac.uk [Key Laboratory of Luminescence and Optical Information, Ministry of Education, Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing 100044 (China)

    2015-06-15

    We report the fabrication of high power conversion efficiency (PCE) polymer/fullerene bulk heterojunction (BHJ) photovoltaic cells using solution-processed Copper (I) Iodide (CuI) as hole transport layer (HTL). Our devices exhibit a PCE value of ∼5.5% which is equivalent to that obtained for control devices based on the commonly used conductive polymer poly(3,4-ethylenedioxythiophene): polystyrenesulfonate as HTL. Inverted cells with PCE >3% were also demonstrated using solution-processed metal oxide electron transport layers, with a CuI HTL evaporated on top of the BHJ. The high optical transparency and suitable energetics of CuI make it attractive for application in a range of inexpensive large-area optoelectronic devices.

  7. Diphenyleneiodonium, an inhibitor of NOXes and DUOXes, is also an iodide-specific transporter

    Directory of Open Access Journals (Sweden)

    C. Massart

    2014-01-01

    Full Text Available NADPH oxidases (NOXes and dual oxidases (DUOXes generate O2.− and H2O2. Diphenyleneiodonium (DPI inhibits the activity of these enzymes and is often used as a specific inhibitor. It is shown here that DPI, at concentrations similar to those which inhibit the generation of O2 derivatives, activated the efflux of radioiodide but not of its analog 99mTcO4− nor of the K+ cation mimic 86Rb+ in thyroid cells, in the PCCl3 rat thyroid cell line and in COS cell lines expressing the iodide transporter NIS. Effects obtained with DPI, especially in thyroid cells, should therefore be interpreted with caution.

  8. Electron and hole drift mobility measurements on methylammonium lead iodide perovskite solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Maynard, Brian; Long, Qi; Schiff, Eric A. [Department of Physics, Syracuse University, Syracuse, New York 13244 (United States); Yang, Mengjin; Zhu, Kai [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Kottokkaran, Ranjith; Abbas, Hisham; Dalal, Vikram L. [Iowa State University, Ames, Iowa 50011 (United States)

    2016-04-25

    We report nanosecond domain time-of-flight measurements of electron and hole photocarriers in methylammonium lead iodide perovskite solar cells. The mobilities ranged from 0.06 to 1.4 cm{sup 2}/Vs at room temperature, but there is little systematic difference between the two carriers. We also find that the drift mobilities are dispersive (time-dependent). The dispersion parameters are in the range of 0.4–0.7, and they imply that terahertz domain mobilities will be much larger than nanosecond domain mobilities. The temperature-dependences of the dispersion parameters are consistent with confinement of electron and hole transport to fractal-like spatial networks within nanoseconds of their photogeneration.

  9. Efficient organic solar cells using copper(I) iodide (CuI) hole transport layers

    Science.gov (United States)

    Peng, Ying; Yaacobi-Gross, Nir; Perumal, Ajay K.; Faber, Hendrik A.; Vourlias, George; Patsalas, Panos A.; Bradley, Donal D. C.; He, Zhiqun; Anthopoulos, Thomas D.

    2015-06-01

    We report the fabrication of high power conversion efficiency (PCE) polymer/fullerene bulk heterojunction (BHJ) photovoltaic cells using solution-processed Copper (I) Iodide (CuI) as hole transport layer (HTL). Our devices exhibit a PCE value of ˜5.5% which is equivalent to that obtained for control devices based on the commonly used conductive polymer poly(3,4-ethylenedioxythiophene): polystyrenesulfonate as HTL. Inverted cells with PCE >3% were also demonstrated using solution-processed metal oxide electron transport layers, with a CuI HTL evaporated on top of the BHJ. The high optical transparency and suitable energetics of CuI make it attractive for application in a range of inexpensive large-area optoelectronic devices.

  10. Lead iodide films as X-ray sensors tested in the mammography energy region

    Energy Technology Data Exchange (ETDEWEB)

    Condeles, J.F. [Departamento de Fisica e Matematica, Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, SP (Brazil)]. E-mail: fernando_condeles@pg.ffclrp.usp.br; Ghilardi Netto, T. [Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto, Universidade de Sao Paulo, Av. Bandeirantes 3900, 14048-900 Ribeirao Preto, SP (Brazil); Mulato, M. [Departamento de Fisica e Matematica, Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, SP (Brazil)

    2007-07-11

    We present an alternative method for the deposition of thin films of lead iodide (PbI{sub 2}), which is a promising semiconductor candidate for applications in medical digital radiography. The spray pyrolysis technique enables the fabrication of thick films with a deposition rate of about 3.3 As{sup -1}. We investigate the influence of the main deposition parameters on the final properties of the films. They were substrate temperature from 150 up to 270 {sup o}C and nozzle-spray distance to substrate from 13.0 to 16.5 cm. The films were mainly investigated using X-ray diffraction (XRD), Atomic Force Microscopy (AFM), and Photoluminescence (PL) spectroscopy. Also, electrical characterizations were made in the dark as a function of temperature, and with the samples submitted to X-ray exposures in the energy range of mammography diagnosis.

  11. Highly Nuclear-Spin-Polarized Deuterium Atoms from the UV Photodissociation of Deuterium Iodide

    Science.gov (United States)

    Sofikitis, Dimitris; Glodic, Pavle; Koumarianou, Greta; Jiang, Hongyan; Bougas, Lykourgos; Samartzis, Peter C.; Andreev, Alexander; Rakitzis, T. Peter

    2017-06-01

    We report a novel highly spin-polarized deuterium (SPD) source, via the photodissociation of deuterium iodide at 270 nm. I (P2 3 /2) photofragments are ionized with m -state selectivity, and their velocity distribution measured via velocity-map slice imaging, from which the D polarization is determined. The process produces ˜100 % electronically polarized D at the time of dissociation, which is then converted to ˜60 % nuclear D polarization after ˜1.6 ns . These production times for SPD allow collision-limited densities of ˜1 018 cm-3 and at production rates of ˜1 021 s-1 which are 1 06 and 1 04 times higher than conventional (Stern-Gerlach separation) methods, respectively. We discuss the production of SPD beams, and combining high-density SPD with laser fusion, to investigate polarized D-T, D -He 3 , and D-D fusion.

  12. Characteristics of organic light emitting diodes with copper iodide as injection layer

    Energy Technology Data Exchange (ETDEWEB)

    Stakhira, P., E-mail: stakhira@polynet.lviv.u [Lviv Polytechnic National University, S. Bandera, 12, Lviv, 79013 (Ukraine); Cherpak, V.; Volynyuk, D.; Ivastchyshyn, F. [Lviv Polytechnic National University, S. Bandera, 12, Lviv, 79013 (Ukraine); Hotra, Z. [Lviv Polytechnic National University, S. Bandera, 12, Lviv, 79013 (Ukraine); Rzeszow University of Technology, W. Pola 2, Rzeszow, 35-959 (Poland); Tataryn, V. [Lviv Polytechnic National University, S. Bandera, 12, Lviv, 79013 (Ukraine); Luka, G. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland)

    2010-09-30

    We have studied the use of a thin copper iodide (CuI) film as an efficient injection layer of holes from indium tin oxide (ITO) anode in a light-emitting diode structure based on tris-8-hydroxyquinoline aluminium (Alq3). The results of impedance analysis of two types of diode structures, ITO/CuI/Alq3/poly(ethylene glycol) dimethyl ether/Al and ITO/Alq3/poly(ethylene glycol) dimethyl ether/Al, are presented. Comparative analysis of their current density-voltage, luminance-voltage and impedance characteristics shows that presence of CuI layer facilitates injection of holes from ITO anode into the light-emitting layer Alq3 and increases electroluminescence efficiency of the organic light emitting diodes.

  13. Luminescent Properties of Cerium Doped Potassium Iodide Single Crystals in Response to γ-irradiation.

    Science.gov (United States)

    Bangaru, S; Saradha, K; Muralidharan, G

    2015-05-01

    Potassium iodide doped with cerium ions were prepared by Bridgemann Stockbarger technique and investigated by optical absorption, Photoluminescence(PL), Thermoluminescence(TL), Photostimulated Luminescence(PSL) and TL emission. The optical absorption measurement indicates that F and V centers are formed in the crystals during the γ-ray irradiation process. Optical absorption and Photoluminescence studies confirm the presence of cerium ions in the trivalent state. Spectral distribution under the Thermoluminescence Emission(TLE) and Optically Stimulated Luminescence(OSL) support the idea that the defect annihilation process to be due to thermal release of F-electron in KI:Ce(3+) crystals. Both Ce(3+) and Ce(2+) emissions were observed in the Thermoluminescence emission of the crystals. Thermoluminescence(TL) has been identified to be due to thermal release of electron produced during colouration process.

  14. Characterization of Resolution and Efficiency of Sodium Iodide Detectors for Reaction Studies

    Science.gov (United States)

    Waddell, Deion; Carls, Alex; Thompson, Paul; Hertz-Kintish, Daniel; G. R. A. N. D. D. A. D Collaboration

    2015-10-01

    The study of nuclear physics with radioactive ion beams requires the understanding of detectors to be used for measuring all types of radiation. Several thallium-activated sodium iodide (NaI(Tl)) detectors were characterized with gamma-ray sources to better understand their properties so they may be utilized for future experiments. A detailed understanding of the resolution and efficiency of the detectors as a function of distance from the sources to the detector, allow us to optimize the detector placement in an experimental setup. Details of the procedure and results will be presented. Work supported in part by the U.S. Department of Energy and the National Science Foundation. Gamma Ray Analysis of NaI Detectors by Daniel Alex and Deion.

  15. Palladium-Catalyzed Reactions of Arylindium Reagents Prepared Directly from Aryl Iodides and Indium Metal

    Science.gov (United States)

    Papoian, Vardan

    2008-01-01

    Treatment of aryl iodides with indium metal in the presence of lithium chloride leads to the formation of an organoindium reagent capable of participating in cross-coupling reactions under transition-metal catalysis. Combination with aryl halides in the presence of 5 mol% Cl2Pd(dppf) furnishes biaryl compounds in good yields; similarly, reaction with acyl halides or allylic acetates/carbonates in the presence of 5–10 mol % palladium catalyst leads to arylketones and allylic substitution products, respectively, in moderate yields. The reactions are tolerant of the presence of protic solvents, and ~85% of the indium metal employed can be recovered by reduction of the residual indium salts with zinc(0). PMID:18722408

  16. Molten phosphonium iodides as electrolytes in dye-sensitized nanocrystalline solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, Rosa E.; Sanchez, Eduardo M. [Laboratorio de Investigacion del Vidrio, Facultad de Ciencias Quimicas, Universidad Autonoma de Nuevo Leon, Pedro de Alba S/N, Cd. Universitaria, San Nicolas de los Garza, N.L. (Mexico)

    2006-09-22

    We have synthesized new room temperature ionic liquids and test them as new potential electrolytes for dye-sensitized nanocrystalline solar cells (DNSCs) of Gratzel type based on asymmetric tetraalkylphosphonium iodides. A systematic study on the conductivity behavior of BH{sub 3}PI, iBH{sub 3}PI, OH{sub 3}PI and iBO{sub 3}PI molten salts and the effect of the addition of low concentrations of iodine with and without 3-methoxypropionitrile is presented. Solar cells using iBH{sub 3}PI-based electrolyte reached an overall light-to-electricity efficiency of 5.7% under moderate light intensity (27000lx) conditions and those results are compared to similar systems using alternative ionic liquids as electrolytes. (author)

  17. Rain on Methylammonium Lead Iodide Based Perovskites: Possible Environmental Effects of Perovskite Solar Cells.

    Science.gov (United States)

    Hailegnaw, Bekele; Kirmayer, Saar; Edri, Eran; Hodes, Gary; Cahen, David

    2015-05-07

    The great promise of hybrid organic-inorganic lead halide perovskite (HOIP)-based solar cells is being challenged by its Pb content and its sensitivity to water. Here, the impact of rain on methylammonium lead iodide perovskite films was investigated by exposing such films to water of varying pH values, simulating exposure of the films to rain. The amount of Pb loss was determined using both gravimetric and inductively coupled plasma mass spectrometry measurements. Using our results, the extent of Pb loss to the environment, in the case of catastrophic module failure, was evaluated. Although very dependent on module siting, even total destruction of a large solar electrical power generating plant, based on HOIPs, while obviously highly undesirable, is estimated to be far from catastrophic for the environment.

  18. Temperature-Dependent Polarization in Field-Effect Transport and Photovoltaic Measurements of Methylammonium Lead Iodide.

    Science.gov (United States)

    Labram, John G; Fabini, Douglas H; Perry, Erin E; Lehner, Anna J; Wang, Hengbin; Glaudell, Anne M; Wu, Guang; Evans, Hayden; Buck, David; Cotta, Robert; Echegoyen, Luis; Wudl, Fred; Seshadri, Ram; Chabinyc, Michael L

    2015-09-17

    While recent improvements in the reported peak power conversion efficiency (PCE) of hybrid organic-inorganic perovskite solar cells have been truly astonishing, there are many fundamental questions about the electronic behavior of these materials. Here we have studied a set of electronic devices employing methylammonium lead iodide ((MA)PbI3) as the active material and conducted a series of temperature-dependent measurements. Field-effect transistor, capacitor, and photovoltaic cell measurements all reveal behavior consistent with substantial and strongly temperature-dependent polarization susceptibility in (MA)PbI3 at temporal and spatial scales that significantly impact functional behavior. The relative PCE of (MA)PbI3 photovoltaic cells is observed to reduce drastically with decreasing temperature, suggesting that such polarization effects could be a prerequisite for high-performance device operation.

  19. Tuning the band gap in hybrid tin iodide perovskite semiconductors using structural templating.

    Science.gov (United States)

    Knutson, Jeremy L; Martin, James D; Mitzi, David B

    2005-06-27

    Structural distortions within the extensive family of organic/inorganic hybrid tin iodide perovskite semiconductors are correlated with their experimental exciton energies and calculated band gaps. The extent of the in- and out-of-plane angular distortion of the SnI4(2-) perovskite sheets is largely determined by the relative charge density and steric requirements of the organic cations. Variation of the in-plane Sn-I-Sn bond angle was demonstrated to have the greatest impact on the tuning of the band gap, and the equatorial Sn-I bond distances have a significant secondary influence. Extended Hückel tight-binding band calculations are employed to decipher the crystal orbital origins of the structural effects that fine-tune the band structure. The calculations suggest that it may be possible to tune the band gap by as much as 1 eV using the templating influence of the organic cation.

  20. High-pressure-induced phase transitions in the ferroelectric bis-thiourea pyridinium iodide inclusion compound

    Energy Technology Data Exchange (ETDEWEB)

    Bilski, P; Bobrowicz-Sarga, L; Czarnecki, P; Maluszynska, H; Wasicki, J [Institute of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland); Natkaniec, I [Frank Laboratory of Neutrons Physics, JINR, 141980 Dubna (Russian Federation)

    2008-12-03

    The effect of temperature and pressure on physical properties of the ferroelectric bis-thiourea pyridinium iodide inclusion compound has been studied by dielectric spectroscopy, neutron spectroscopy, neutron powder diffractometry, single crystal x-ray diffraction and nuclear magnetic resonance (NMR). At ambient pressure two structural phase transitions have been revealed: at T{sub 1} = 161 K between phases I and II and at T{sub 2} = 141 K between phases II and III. Phase III with increasing pressure splits into two phases, IIIa and IIIb. The temperatures of the phase transitions T{sub I-II}, T{sub II-IIIa} and T{sub IIIa-IIIb} increase with increasing pressure. The p-T phase diagram constructed for this compound shows two triple points of coordinates 150 K, 100 MPa and 115 K, 100 MPa.

  1. The Inhibition Effect of Potassium Iodide on the Corrosion of Pure Iron in Sulphuric Acid

    Directory of Open Access Journals (Sweden)

    Tarik Attar

    2014-01-01

    Full Text Available The use of inorganic inhibitors as an alternative to organic compounds is based on the possibility of degradation of organic compounds with time and temperature. The inhibition effect of potassium iodide on the corrosion of pure iron in 0.5 M H2SO4 has been studied by weight loss. It has been observed from the results that the inhibition efficiency (IE% of KI increases from 82.17% to 97.51% with the increase in inhibitor concentration from 1·10−4 to 2·10−3 M. The apparent activation energy (Ea and the equilibrium constant of adsorption (Kads were calculated. The adsorption of the inhibitor on the pure iron surface is in agreement with Langmuir adsorption isotherm.

  2. Quasi-gel-state ionic liquid electrolyte with alkyl-pyrazolium iodide for dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ishimaru, Noriyo; Kubo, Wataru; Kitamura, Takayuki [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Yanagida, Shozo [Center for Advanced Science and Innovation, Osaka University, Yamadaoka 2-1, Suita, Osaka 565-0871 (Japan); Tsukahara, Yasunori [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Maitani, Masato M. [Department of Applied Chemistry, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguroku, Tokyo 152-8552 (Japan); Wada, Yuji, E-mail: yuji-w@apc.titech.ac.jp [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Department of Applied Chemistry, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguroku, Tokyo 152-8552 (Japan)

    2011-08-15

    Highlights: > The dye sensitized solar cells (DSSC) using quasi-gel-state ionic liquid electrolyte. > We synthesized 1-alkyl-2-methylpyrazolium iodides (PyI) for the electrolytes of DSSC. > The viscosity of PyI were higher than that of the imidazolium iodide electrolytes (ImI). > DSSC using the PyI exhibited the high Jsc and efficiency than that using ImI. > In PyI, the rapid diffusion of charge carriers, Grotthus-like model, was predominant. - Abstract: A series of non-volatile viscous ionic liquid, 1-alkyl-2-methylpyrazolium iodides (RPyI: R = C{sub 3}-C{sub 7}), were synthesized for the electrolyte of dye-sensitized solar cells (DSSC). Most of RPyI revealed extremely viscous quasi-gel-state electrolytes potentially preventing leakage and evaporation of electrolytes of the solar cells. A DSSC using the electrolyte composed of 1-hexyl-2-methylpyrazolium iodide (C{sub 6}PyI) with iodine exhibiting higher conversion efficiency of 3.8% (under 1 Sun) for 10% larger short-circuit photocurrent, J{sub SC}, than that with a conventional ionic liquid, 1-hexyl-3-methyllimidazolium iodide (C{sub 6}ImI) with iodine, in spite of less favorable viscosity (2013 mPa s (C{sub 6}PyI/I{sub 2}) vs. 1439 mPa s (C{sub 6}ImI/I{sub 2})) for the physical diffusion of charge carriers in the electrolyte. Furthermore, the quasi-gel-state electrolytes composed of a series of RPyI ionic liquids surprisingly exhibiting comparable J{sub SC} to that with much less viscous C{sub 6}ImI/I{sub 2}. We discuss the results of quasi-gel-state RPyI ionic liquid electrolyte for DSSC based on the Grotthus-like electron exchange mechanism of iodide redox species in the highly viscous RPyI ionic liquid evaluated qualitatively by Raman spectroscopic observation of poly-iodide species.

  3. The Role of Connectivity on Electronic Properties of Lead Iodide Perovskite-Derived Compounds

    Science.gov (United States)

    2017-01-01

    We use a layered solution crystal growth method to synthesize high-quality single crystals of two different benzylammonium lead iodide perovskite-like organic/inorganic hybrids. The well-known (C6H5CH2NH3)2PbI4 phase is obtained in the form of bright orange platelets, with a structure comprised of single ⟨100⟩-terminated sheets of corner-sharing PbI6 octahedra separated by bilayers of the organic cations. The presence of water during synthesis leads to formation of a novel minority phase that crystallizes in the form of nearly transparent, light yellow bar-shaped crystals. This phase adopts the monoclinic space group P21/n and incorporates water molecules, with structural formula (C6H5CH2NH3)4Pb5I14·2H2O. The crystal structure consists of ribbons of edge-sharing PbI6 octahedra separated by the organic cations. Density functional theory calculations including spin–orbit coupling show that these edge-sharing PbI6 octahedra cause the band gap to increase with respect to corner-sharing PbI6 octahedra in (C6H5CH2NH3)2PbI4. To gain systematic insight, we model the effect of the connectivity of PbI6 octahedra on the band gap in idealized lead iodide perovskite-derived compounds. We find that increasing the connectivity from corner-, via edge-, to face-sharing causes a significant increase in the band gap. This provides a new mechanism to tailor the optical properties in organic/inorganic hybrid compounds. PMID:28677956

  4. Imaging and targeted therapy of pancreatic ductal adenocarcinoma using the theranostic sodium iodide symporter (NIS) gene.

    Science.gov (United States)

    Schmohl, Kathrin A; Gupta, Aayush; Grünwald, Geoffrey K; Trajkovic-Arsic, Marija; Klutz, Kathrin; Braren, Rickmer; Schwaiger, Markus; Nelson, Peter J; Ogris, Manfred; Wagner, Ernst; Siveke, Jens T; Spitzweg, Christine

    2017-05-16

    The theranostic sodium iodide symporter (NIS) gene allows detailed molecular imaging of transgene expression and application of therapeutic radionuclides. As a crucial step towards clinical application, we investigated tumor specificity and transfection efficiency of epidermal growth factor receptor (EGFR)-targeted polyplexes as systemic NIS gene delivery vehicles in an advanced genetically engineered mouse model of pancreatic ductal adenocarcinoma (PDAC) that closely reflects human disease. PDAC was induced in mice by pancreas-specific activation of constitutively active KrasG12D and deletion of Trp53. We used tumor-targeted polyplexes (LPEI-PEG-GE11/NIS) based on linear polyethylenimine, shielded by polyethylene glycol and coupled with the EGFR-specific peptide ligand GE11, to target a NIS-expressing plasmid to high EGFR-expressing PDAC. In vitro iodide uptake studies in cell explants from murine EGFR-positive and EGFR-ablated PDAC lesions demonstrated high transfection efficiency and EGFR-specificity of LPEI-PEG-GE11/NIS. In vivo 123I gamma camera imaging and three-dimensional high-resolution 124I PET showed significant tumor-specific accumulation of radioiodide after systemic LPEI-PEG-GE11/NIS injection. Administration of 131I in LPEI-PEG-GE11/NIS-treated mice resulted in significantly reduced tumor growth compared to controls as determined by magnetic resonance imaging, though survival was not significantly prolonged. This study opens the exciting prospect of NIS-mediated radionuclide imaging and therapy of PDAC after systemic non-viral NIS gene delivery.

  5. Delayed cognitive and psychiatric symptoms following methyl iodide and manganese poisoning: Potential for misdiagnosis.

    Science.gov (United States)

    Mackenzie Ross, Sarah

    2016-01-01

    This paper describes two patients who were exposed to toxic substances in the workplace, but for whom diagnosis proved difficult, particularly in case 2. Case 1 was exposed to methyl iodide and case 2 to manganese. Poisoning was characterised by delayed onset of symptoms following exposure and symptom progression after cessation of exposure. The clinical consequences of exposure to these substances include cerebellar and Parkinsonian symptoms followed by the development of cognitive impairment and the late appearance of psychiatric disturbances. Both cases were evaluated by physicians with little training in toxicology. Apart from abnormal liver function in case 1 and decreased power, coordination and proprioception in case 2, results of most routine medical investigations were normal. Both cases were referred for MRI brain scan and neuropsychological assessment. Abnormalities were noted on MRI but reported as being absent initially in case 1and of unknown significance in case 2. There was evidence of cognitive impairment in both and personality change in case 1 of sufficient severity to prevent both cases from returning to work and to impact on family life. There is no antidote to methyl iodide or manganese poisoning. Successful treatment requires early diagnosis and cessation of exposure, but neurotoxic syndromes are difficult to diagnose when a time lag exists between exposure and symptom onset and there is no biomarker of exposure. These syndromes may initially be confused with other neurodegenerative conditions, infectious processes, and psychiatric disorders. Clinician's lack of familiarity with the potential toxicity of environmental and industrial chemicals can lead to misdiagnosis and mismanagement, and this lack of recognition can lead to continued exposure. These cases highlight the importance of taking a detailed occupational history in patients who present with atypical neurological symptoms. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Diffusional analysis of the adsorption of methyl iodide on silver exchanged mordenite

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T. [Oak Ridge National Lab., TN (United States); Counce, R.M. [Univ. of Tennessee, Knoxville, TN (United States)

    1997-08-01

    The removal of organic iodides from off-gas streams is an important step in controlling the release of radioactive iodine to the environment during the treatment of radioactive wastes or the processing of some irradiated materials. Nine-well accepted mass transfer models were evaluated for their ability to adequately explain the observed CH{sub 3}I uptake behavior onto the Ag{degrees}Z. Linear and multidimensional regression techniques were used to estimate the diffusion constants and other model parameters, which then permitted the selection of an appropriate mass transfer model. Although a number of studies have been conducted to evaluate the loading of both elemental and methyl iodide on silver-exchanged mordenite, these studies focused primarily on the macro scale (deep bed) while evaluating the material under a broad range of process conditions and contaminants for total bed loading at the time of breakthrough. A few studies evaluated equilibrium or maximum loading. Thus, to date, only bulk loading data exist for the adsorption of CH{sub 3}I onto Ag{degrees}Z. Hence this is believed to be the first study to quantify the controlling mass transfer mechanisms of this process, It can be concluded from the analysis of the experimental data obtained by the {open_quotes}single-pellet{close_quotes} type experiments and for the process conditions used in this study that the overall mass transfer rate associated with the adsorption of CH{sub 3}I onto Ag{degrees}Z is affected by both micropore and macropore diffusion. The macropore diffusion rate was significantly faster than the micropore diffusion, resulting in a two-step adsorption behavior which was adequately modeled by a bimodal pore distribution model. The micropore diffusivity was determined to be on the order of 2 x 10{sup -14} cm{sup 2}/s. The system was also shown to be isothermal under all conditions of this study. 21 refs., 6 figs., 8 tabs.

  7. Subcellular distribution of the sodium iodide symporter in benign and malignant thyroid tissues.

    Science.gov (United States)

    Kollecker, Inga; von Wasielewski, Reinhard; Langner, Cord; Müller, Jörg Andreas; Spitzweg, Christine; Kreipe, Hans; Brabant, Georg

    2012-05-01

    Membranous expression of the sodium iodide symporter (NIS) is a prerequisite for iodide uptake in thyrocytes. Previous studies reported heterogeneous results on the relative frequency of staining in various pathological conditions of the thyroid. The present study aimed at determining membranous staining by using confocal laser microscopy in benign and malignant thyroid diseases, complemented in a subgroup of patients with recurrent or metastatic disease with functional findings of radioiodine uptake (RIU). There were 380 malignant thyroid tumors (145 papillary, 51 follicular, 87 Hurthle cell, and 97 undifferentiated thyroid carcinomas [UTC]), 115 benign adenomas, 62 diffuse goiters, 89 inflammatory conditions (Graves', Hashimoto, Thyroiditis deQuervain, and lymphocytic thyroiditis), and 179 normal tissues (NT, fetal, and adult). These were subjected to NIS (two different antibodies) and thyroglobulin (TG) staining and evaluated by confocal microscopy. In a subgroup of 50 samples from patients with recurrent or metastatic disease, NIS staining was correlated with the RIU. As compared with NT, Graves' patients had significantly higher positive NIS membrane staining (>97% vs. 69%) whereas patients with Hashimoto, lymphocytic thyroiditis but also benign adenomas scored lower than NT (56.7% and 55.8% vs. 69%). Depending on their differentiation NIS staining was significantly lower in thyroid carcinomas in parallel with TG staining with only 1/97 UTCs being positive. RIU was more frequently detectable than NIS staining. Confocal staining strictly evaluating only membranous expression of NIS has not used on a large scale before this study. We confirm the loss of membranous NIS in benign but more prominently in malignant thyroid tumors. NIS staining of diagnostic tissues cannot be used to predict RIU.

  8. Silver nanoplates-based colorimetric iodide recognition and sensing using sodium thiosulfate as a sensitizer

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Xinyan; Chen, Shu, E-mail: chenshumail@gmail.com; Tang, Jian; Xiong, Yuan; Long, Yunfei, E-mail: l_yunfei927@163.com

    2014-05-01

    Highlights: • A new colorimetric iodide detection strategy based on triangular Ag nanoplate. • Sodium thiosulfate performed as a sensitizer. • Formation of insoluble AgI on the surface of Ag nanoplate. • This method has the advantages of good selectivity and high sensitivity. Abstract: A colorimetric method for the recognition and sensing of iodide ions (I⁻) has been developed by utilizing the reactions between triangular silver nanoplates (TAg-NPs) and I⁻ in the presence of sodium thiosulfate (Na₂S₂O₃). Specifically, I⁻ together with Na₂S₂O₃ can induce protection of TAg-NPs owing to the formation of insoluble AgI, as confirmed by the high-resolution transmission electron microscopy (HRTEM). In the absence of Na₂S₂O₃, the etching reactions on TAg-NPs were observed not only by I⁻ but also other halides ions. The Na₂S₂O₃ plays as a sensitizer in this system, which improved the selectivity and sensitivity. The desired colorimetric detection can be achieved by measuring the change of the absorption peak wavelength corresponding to localized surface plasmon resonance (LSPR) with UV–vis spectrophotometer or recognized by naked eye observation. The results show that the shift of the maximum absorption wavelength (Δλ) of the TAg-NPs/Na₂S₂O₃/I⁻ mixture was proportional to the concentration of I⁻ in the range 1.0 × 10⁻⁹–1.0 × 10⁻⁶ mol L⁻¹. Moreover, no other ions besides I⁻ can induce an eye discernible color change as low as 1.0 × 10⁻⁷ mol L⁻¹. Finally, this method was successfully applied for I⁻ determination in kelp samples.

  9. Spatial distribution of perchlorate, iodide and thiocyanate in the aquatic environment of Tianjin, China: environmental source analysis.

    Science.gov (United States)

    Qin, Xiaolei; Zhang, Tao; Gan, Zhiwei; Sun, Hongwen

    2014-09-01

    Although China is the largest producer of fireworks (perchlorate-containing products) in the world, the pathways through which perchlorate enters the environment have not been characterized completely in this country. In this study, perchlorate, iodide and thiocyanate were measured in 101 water samples, including waste water, surface water, sea water and paired samples of rain water and surface runoff collected in Tianjin, China. The concentrations of the target anions were generally on the order of rain>surface water≈waste water treatment plant (WWTP) influent>WWTP effluent. High concentrations of perchlorate, iodide and thiocyanate were detected in rain samples, ranging from 0.35 to 27.3 (median: 4.05), 0.51 to 8.33 (2.92), and 1.31 to 107 (5.62) ngmL(-)(1), respectively. Furthermore, the concentrations of the target anions in rain samples were significantly (r=0.596-0.750, p<0.01) positively correlated with the concentrations obtained in the paired surface runoff samples. The anions tested showed a clear spatial distribution, and higher concentrations were observed in the upper reaches of rivers, sea waters near the coast, and rain-surface runoff pairs sampled in urban areas. Our results revealed that precipitation may act as an important source of perchlorate, iodide and thiocyanate in surface water. Moreover, iodide concentrations in the Haihe River and Dagu Drainage Canal showed a good correlation with an ideal marker (acesulfame) of domestic waste water, indicating that input from domestic waste water was an important source of iodide in the surface waters of Tianjin. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Dialkylmethyl-2-(N,N-diisobutyl)acetamidoammonium iodide as a ruthenium selective ligand from nitric acid medium

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Shikha [Bio-Organic Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India); Ghosh, Sunil K., E-mail: ghsunil@barc.gov.in [Bio-Organic Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India); Sharma, Joti N., E-mail: jnsharma@barc.gov.in [Process Development Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2015-09-15

    Highlights: • A new class of quart-ammonium based ligands have been designed and synthesized. • Ligand showed high extractability and selectivity for Ru in nitric acid medium. • Results are better compared to other extractants reported so far. • The iodide ion played key role in extraction process. • The composition of the extracted complex was found to be L[Ru(NO)(NO{sub 3}){sub 3}I]. - Abstract: A new class of quaternary ammonium iodide based ligands with 2-(N,N-diisobutyl)acetamide as an alkyl appendage have been designed, synthesized and tested for their ability to extract ruthenium selectively from nitric acid medium. The 2-(N,N-diisobutyl)acetamido ammonium iodide with two propyl and a methyl substituents showed best results for the recovery of ruthenium. The optimized concentration of the solvent was found to be 0.2 M in 30% isodecyl alcohol/n-dodecane. The stoichiometry of the complex was ascertained by slope analysis method and was found to be 1:1 with respect to ligand L{sup +}I{sup −} and Ru(NO)(NO{sub 3}){sub 3}. Ruthenium formed an adduct of structure LRu(NO)(NO{sub 3}){sub 3}I in the extraction medium. Iodide ion played an important role in the formation of the stable and extractable complex of ruthenium. No extraction was observed when iodide was replaced by nitrate anion in the ligand. The ligand also showed good selectivity for ruthenium in the presence of other metal ions commonly found in nitric acid solutions of nuclear waste.

  11. Comparison of expressed human and mouse sodium/iodide sym-porters reveals differences in transport properties and subcellular localization

    Energy Technology Data Exchange (ETDEWEB)

    Dayem, M.; Basquin, C.; Navarro, V.; Carrier, P.; Marsault, R.; Lindenthal, S.; Pourcher, T. [Univ Nice Sophia Antipolis, Sch Med, CEA, DSV, iBEB, SBTN, TIRO, F-06107 Nice (France); Chang, P. [CNRS, UPMC Biol Dev, UMR 7009, F-06230 Villefranche Sur Mer (France); Huc, S.; Darrouzet, E. [CEA Valrho, DSV, iBEB, SBTN, F-30207 Bagnols Sur Ceze (France)

    2008-07-01

    The active transport of iodide from the blood stream into thyroid follicular cells is mediated by the Na{sup +}/I{sup -} sym-porter (NIS). We studied mouse NIS (mNIS) and found that it catalyzes iodide transport into transfected cells more efficiently than human NIS (hNIS). To further characterize this difference,we compared {sup 125}I, uptake in the transiently transfected human embryonic kidney (HEK) 293 cells. We found that the Vmax for mNIS was four times higher than that for hNIS, and that the iodide transport constant (Km) was 2-5-fold lower for hNIS than mNIS. We also performed immuno-cyto-localization studies and observed that the subcellular distribution of the two ortho-logs differed. While the mouse protein was predominantly found at the plasma membrane, its human ortho-log was intracellular in {approx} 40% of the expressing cells. Using cell surface protein-labeling assays, we found that the plasma membrane localization frequency of the mouse protein was only 2-5-fold higher than that of the human protein, and therefore cannot alone account for,x values. We reasoned that the difference in the obtained Vmax the observed difference could also be caused by a higher turnover number for iodide transport in the mouse protein. We then expressed and analyzed chimeric proteins. The data obtained with these constructs suggest that the iodide recognition site could be located in the region extending from the N-terminus to transmembrane domain 8, and that the region between transmembrane domain 5 and the C-terminus could play a role in the subcellular localization of the protein. (authors)

  12. An integrated logic system for time-resolved fluorescent "turn-on" detection of cysteine and histidine base on terbium (III) coordination polymer-copper (II) ensemble.

    Science.gov (United States)

    Xue, Shi-Fan; Lu, Ling-Fei; Wang, Qi-Xian; Zhang, Shengqiang; Zhang, Min; Shi, Guoyue

    2016-09-01

    Cysteine (Cys) and histidine (His) both play indispensable roles in many important biological activities. An enhanced Cys level can result in Alzheimer's and cardiovascular diseases. Likewise, His plays a significant role in the growth and repair of tissues as well as in controlling the transmission of metal elements in biological bases. Therefore, it is meaningful to detect Cys and His simultaneously. In this work, a novel terbium (III) coordination polymer-Cu (II) ensemble (Tb(3+)/GMP-Cu(2+)) was proposed. Guanosine monophosphate (GMP) can self-assemble with Tb(3+) to form a supramolecular Tb(3+) coordination polymer (Tb(3+)/GMP), which can be suited as a time-resolved probe. The fluorescence of Tb(3+)/GMP would be quenched upon the addition of Cu(2+), and then the fluorescence of the as-prepared Tb(3+)/GMP-Cu(2+) ensemble would be restored again in the presence of Cys or His. By incorporating N-Ethylmaleimide and Ni(2+) as masking agents, Tb(3+)/GMP-Cu(2+) was further exploited as an integrated logic system and a specific time-resolved fluorescent "turn-on" assay for simultaneously sensing His and Cys was designed. Meanwhile it can also be used in plasma samples, showing great potential to meet the need of practical application. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Synthesis and photoluminescence properties of cerium-doped terbium-yttrium aluminum garnet phosphor for white light-emitting diodes applications

    Science.gov (United States)

    Wang, Jun; Han, Tao; Lang, Tianchun; Tu, Mingjing; Peng, Lingling

    2015-11-01

    Cerium-doped terbium-yttrium aluminum garnet phosphors were synthesized using the solid-state reaction method. The crystalline phase, morphology, and photoluminescence properties were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), and fluorescence spectrophotometer, respectively. The XRD results indicate that with an increase of the amount of x (Tb3+), all of the samples have a pure garnet crystal structure without secondary phases. The SEM images reveal that the samples are composed of sphere-like crystallites, which exhibit different degrees of agglomeration. The luminescent properties of Ce ions in )Al5O12∶Ce0.1 have been studied, and it was found that the emission band shifted toward a longer wavelength. The redshift is attributed to the lowering of the 5d energy level centroid of Ce, which can be explained by the nephelauxetic effect and compression effect. These phosphors were coated on blue light-emitting diode (LED) chips to fabricate white light-emitting diodes (WLEDs), and their color-rendering indices, color temperatures, and luminous efficiencies were measured. As a consequence of the addition of Tb, the blue LED pumped )Al5O12∶Ce0.1 phosphors WLEDs showed good optical properties.

  14. Study on the fluorescent enhancement effect in terbium-gadolinium-protein-sodium dodecyl benzene sulfonate system and its application on sensitive detection of protein at nanogram level.

    Science.gov (United States)

    Sun, Changxia; Yang, Jinghe; Wu, Xia; Liu, Shufang; Su, Benyu

    2004-08-01

    The co-luminescence effect in a terbium-gadolinium-protein-sodium dodecyl benzene sulfonate (SDBS) system is reported here. Based on it, the sensitive quantitative analysis of protein at nanogram levels is established. The co-luminescence mechanism is studied using fluorescence, resonance light scattering (RLS), absorption spectroscopy and NMR measurement. It is considered that protein could be unfolded by SDBS, then a efficacious intramolecular fluorescent energy transfer occurs from unfolded protein to rare earth ions through SDBS acting as a "transfer bridge" to enhance the emission fluorescence of Tb3+ in this ternary complex of Tb-SDBS-BSA, where energy transfer from protein to SDBS by aromatic ring stacking is the most important step. Cooperating with the intramolecular energy transfer above is the intermolecular energy transfer between the simultaneous existing complexes of both Tb3+ and Gd3+. The fluorescence quantum yield is increased by an energy-insulating sheath, which is considered to be another reason for the resulting enhancement of the fluorescence. Förster theory is used to calculate the distribution of enhancing factors and has led to a greater understanding of the mechanisms of energy transfer.

  15. [Studies on luminescence properties of seven ternary complexes of terbium with 1,10-phenanthroline and benzoic acid and its derivatives].

    Science.gov (United States)

    Gao, Zhi-hua; Wang, Shu-ping; Liu, Cui-ge; Ma, Rui-xia; Wang, Rui-fen

    2006-04-01

    Seven ternary complexes of Tb(III) were synthesized with benzoic acid (BA), o-, m-, p-methylbenzoic acid (o-MBA, m-MBA, p-MBA), and o-, m-, p-methoxybenzoic acid (o-MOBA, m-MOBA, p-MOBA) as the first ligand, and 1,10-phenanthroline (phen) as the second ligand. The content of C, H and N were measured by using a Flash-EA model 1112 elemental analyzer. Excitation and luminescence spectra of the title solid complexes were recorded by using a Hitachi F-4500 fluorescence spectrophotometer at room temperature. The effects of different varieties and different positions of replacing benzoic acid as the first ligand on fluorescence properties of the ternary complexes of terbium were discussed. The results indicated that the intensity of 5D4-->7F6 (489 nm) and 5D4-->7F5 (545 nm) of substituting benzoic acid complexes was stronger than benzoic acid. Three ternary complexes of Tb(III) with o-, m-, p-methylbenzoic acid showed emission intensity in the consecution: Tb(o-MBA)3 phenMOBA)3phen x H2O>Tb(m-MOBA)3phen x H2O>Tb(p-MOBA)3 phen.

  16. Antibacterial properties of copper iodide-doped glass ionomer-based materials and effect of copper iodide nanoparticles on collagen degradation.

    Science.gov (United States)

    Renné, Walter G; Lindner, Amanda; Mennito, Anthony S; Agee, Kelli A; Pashley, David H; Willett, Daniel; Sentelle, David; Defee, Michael; Schmidt, Michael; Sabatini, Camila

    2017-01-01

    This study investigated the antibacterial properties and micro-hardness of polyacrylic acid (PAA)-coated copper iodide (CuI) nanoparticles incorporated into glass ionomer-based materials, and the effect of PAA-CuI on collagen degradation. PAA-CuI nanoparticles were incorporated into glass ionomer (GI), Ionofil Molar AC, and resin-modified glass ionomer (RMGI), Vitrebond, at 0.263 wt%. The antibacterial properties against Streptococcus mutans (n = 6/group) and surface micro-hardness (n = 5/group) were evaluated. Twenty dentin beams were completely demineralized in 10 wt% phosphoric acid and equally divided in two groups (n = 10/group) for incubation in simulated body fluid (SBF) or SBF containing 1 mg/ml PAA-CuI. The amount of dry mass loss and hydroxyproline (HYP) released were quantified. Kruskal-Wallis, Student's t test, two-way ANOVA, and Mann-Whitney were used to analyze the antibacterial, micro-hardness, dry mass, and HYP release data, respectively (p glass ionomer matrix yielded significant reduction (99.999 %) in the concentration of bacteria relative to the control groups. While micro-hardness values of PAA-CuI-doped GI were no different from its control, PAA-CuI-doped RMGI demonstrated significantly higher values than its control. A significant decrease in dry mass weight was shown only for the control beams (10.53 %, p = 0.04). Significantly less HYP was released from beams incubated in PAA-CuI relative to the control beams (p glass ionomer-based materials as they greatly enhance their antibacterial properties and reduce collagen degradation without an adverse effect on their mechanical properties. The use of copper-doped glass ionomer-based materials under composite restorations may contribute to an increased longevity of adhesive restorations, because of their enhanced antibacterial properties and reduced collagen degradation.

  17. Influence of Cations on the Fluorescence Quenching of an Ionic, Sterically Congested Pyrenyl Moiety by Iodide in Water.

    Science.gov (United States)

    Bertocchi, Michael J; Lupicki, Adam; Bajpai, Alankriti; Moorthy, Jarugu N; Weiss, Richard G

    2017-10-12

    Quenching of the excited singlet states of a water-soluble, sterically congested tetraarylpyrene, 1,3,6,8-tetrakis(2,6-dimethyl-4-(α-carboxy)methoxyphenyl)pyrene (Py4C), by a series of iodide salts has been investigated by steady-state and time-resolved fluorescence measurements. Access to the pyrenyl group of Py4C is restricted sterically as a result of the four flanking (2,6-dimethylphenoxy)acetic acid groups and the energy costs associated with their rotation. Deprotonation of the carboxylic acid groups of Py4C permits examination of ion-ion electrostatic interactions on the rates of quenching by iodide salts in which different steric and electrostatic factors are introduced by varying the cationic portions. At the same concentrations and with the same cations, chloride anions are ineffective quenchers. The quenching rate constants of Py4C by iodide are found to correlate linearly with the ionic radii of the cations and their enthalpies of hydration. These correlations are discussed in terms of the Hofmeister series. Furthermore, the results indicate that the cations that flank Py4C decrease the quenching efficiency of iodide through polarization and shielding effects (i.e., lowering the effective charge), which isolate to varying degrees the π-system. The effects of the different cations on quenching the fluorescence of a simpler and sterically unencumbered pyrenyl derivative, 1-pyrenylbutyric acid (PyBu), by iodide are much smaller. Overall, the results with Py4C indicate that the fluorescence quenching efficiency by iodide is influenced by direct interactions with the cations associated with the carboxylate groups of Py4C and not the solvation of water molecules. This observation is germane to a topic of current debate: Are the effects of the cations more closely related to bulk water properties or to direct ion-ion interactions? The conclusions obtained from these studies are applicable clearly to a wide variety of other systems in which ion pairing

  18. Global sea-to-air flux climatology for bromoform, dibromomethane and methyl iodide

    Directory of Open Access Journals (Sweden)

    F. Ziska

    2013-09-01

    Full Text Available Volatile halogenated organic compounds containing bromine and iodine, which are naturally produced in the ocean, are involved in ozone depletion in both the troposphere and stratosphere. Three prominent compounds transporting large amounts of marine halogens into the atmosphere are bromoform (CHBr3, dibromomethane (CH2Br2 and methyl iodide (CH3I. The input of marine halogens to the stratosphere has been estimated from observations and modelling studies using low-resolution oceanic emission scenarios derived from top-down approaches. In order to improve emission inventory estimates, we calculate data-based high resolution global sea-to-air flux estimates of these compounds from surface observations within the HalOcAt (Halocarbons in the Ocean and Atmosphere database (https://halocat.geomar.de/. Global maps of marine and atmospheric surface concentrations are derived from the data which are divided into coastal, shelf and open ocean regions. Considering physical and biogeochemical characteristics of ocean and atmosphere, the open ocean water and atmosphere data are classified into 21 regions. The available data are interpolated onto a 1°×1° grid while missing grid values are interpolated with latitudinal and longitudinal dependent regression techniques reflecting the compounds' distributions. With the generated surface concentration climatologies for the ocean and atmosphere, global sea-to-air concentration gradients and sea-to-air fluxes are calculated. Based on these calculations we estimate a total global flux of 1.5/2.5 Gmol Br yr−1 for CHBr3, 0.78/0.98 Gmol Br yr−1 for CH2Br2 and 1.24/1.45 Gmol Br yr−1 for CH3I (robust fit/ordinary least squares regression techniques. Contrary to recent studies, negative fluxes occur in each sea-to-air flux climatology, mainly in the Arctic and Antarctic regions. "Hot spots" for global polybromomethane emissions are located in the equatorial region, whereas methyl iodide emissions are enhanced in the

  19. Investigations regarding the wet decontamination of fluorescent lamp waste using iodine in potassium iodide solutions

    Energy Technology Data Exchange (ETDEWEB)

    Tunsu, Cristian, E-mail: tunsu@chalmers.se; Ekberg, Christian; Foreman, Mark; Retegan, Teodora

    2015-02-15

    Highlights: • A wet-based decontamination process for fluorescent lamp waste is proposed. • Mercury can be leached using iodine in potassium iodide solution. • The efficiency of the process increases with an increase in leachant concentration. • Selective leaching of mercury from rare earth elements is achieved. • Mercury is furthered recovered using ion exchange, reduction or solvent extraction. - Abstract: With the rising popularity of fluorescent lighting, simple and efficient methods for the decontamination of discarded lamps are needed. Due to their mercury content end-of-life fluorescent lamps are classified as hazardous waste, requiring special treatment for disposal. A simple wet-based decontamination process is required, especially for streams where thermal desorption, a commonly used but energy demanding method, cannot be applied. In this study the potential of a wet-based process using iodine in potassium iodide solution was studied for the recovery of mercury from fluorescent lamp waste. The influence of the leaching agent’s concentration and solid/liquid ratio on the decontamination efficiency was investigated. The leaching behaviour of mercury was studied over time, as well as its recovery from the obtained leachates by means of anion exchange, reduction, and solvent extraction. Dissolution of more than 90% of the contained mercury was achieved using 0.025/0.05 M I{sub 2}/KI solution at 21 °C for two hours. The efficiency of the process increased with an increase in leachant concentration. 97.3 ± 0.6% of the mercury contained was dissolved at 21 °C, in two hours, using a 0.25/0.5 M I{sub 2}/KI solution and a solid to liquid ratio of 10% w/v. Iodine and mercury can be efficiently removed from the leachates using Dowex 1X8 anion exchange resin or reducing agents such as sodium hydrosulphite, allowing the disposal of the obtained solution as non-hazardous industrial wastewater. The extractant CyMe{sub 4}BTBP showed good removal of mercury

  20. Iodide and triiodide anion complexes involving anion-π interactions with a tetrazine-based receptor.

    Science.gov (United States)

    Savastano, Matteo; Bazzicalupi, Carla; García, Celeste; Gellini, Cristina; López de la Torre, María Dolores; Mariani, Palma; Pichierri, Fabio; Bianchi, Antonio; Melguizo, Manuel

    2017-04-05

    Protonated forms of the tetrazine ligand L2 (3,6-bis(morpholin-4-ylethyl)-1,2,4,5-tetrazine) interact with iodide in aqueous solution forming relatively stable complexes (ΔG° = -11.6(4) kJ mol(-1) for HL2(+) + I(-) = (HL2)I and ΔG° = -13.4(2) kJ mol(-1) for H2L2(2+) + I(-) = [(H2L2)I](+)). When solutions of [(H2L2)I](+) are left in contact with air, crystals of the oxidation product (H2L2)2(I3)3I·4H2O are formed. Unfortunately, the low solubility of I3(-) complexes prevents the determination of their stability constants. The crystal structures of H2L2I2·H2O (1), H2L2(I3)2·2H2O (2) and (H2L2)2(I3)3I·4H2O (3) were determined by means of X-ray diffraction analyses. In all crystal structures, it was found that the interaction between I(-) and I3(-) with H2L2(2+) is dominated by anion interactions with the π electron density of the receptor. Only in the case of 1, the iodide anions involved in close anion-π interactions with the ligand tetrazine ring form an additional H-bond with the protonated morpholine nitrogen of an adjacent ligand molecule. Conversely, in crystals of 2 and 3 there are alternate segregated planes which contain only protonated ligands hydrogen-bonded to cocrystallized water molecules or I3(-) and I(-) forming infinite two-dimensional networks established through short interhalogen contacts, making these crystalline products good candidates to behave as solid conductors. In the solid complexes, the triiodide anion displays both end-on and side-on interaction modes with the tetrazine ring, in agreement with density functional theory calculations indicating a preference for the alignment of the I3(-) molecular axis with the molecular axis of the ligand. Further information about geometries and structures of triiodide anions in 2 and 3 was acquired by the analysis of their Raman spectra.

  1. Assessment of methods for methyl iodide emission reduction and pest control using a simulation model

    Science.gov (United States)

    Luo, Lifang; Ashworth, Daniel J.; Šimunek, Jirka; Xuan, Richeng; Yates, Scott R.

    2013-02-01

    The increasing registration of the fumigant methyl iodide within the USA has led to more concerns about its toxicity to workers and bystanders. Emission mitigation strategies are needed to protect the public and environmental health while providing effective pest control. The effectiveness of various methods on emissions reduction and pest control was assessed using a process-based mathematical model in this study. Firstly, comparisons between the simulated and laboratory measured emission fluxes and cumulative emissions were made for methyl iodide (MeI) under four emission reduction treatments: 1) control, 2) using soil with high organic matter content (HOM), 3) being covered by virtually impermeable film (VIF), and 4) irrigating soil surface following fumigation (Irrigation). Then the model was extended to simulate a broader range of emission reduction strategies for MeI, including 5) being covered by high density polyethylene (HDPE), 6) increasing injection depth from 30 cm to 46 cm (Deep), 7) HDPE + Deep, 8) adding a reagent at soil surface (Reagent), 9) Reagent + Irrigation, and 10) Reagent + HDPE. Furthermore, the survivability of three types of soil-borne pests (citrus nematodes [Tylenchulus semipenetrans], barnyard seeds [Echinochloa crus-galli], fungi [Fusarium oxysporum]) was also estimated for each scenario. Overall, the trend of the measured emission fluxes as well as total emission were reasonably reproduced by the model for treatments 1 through 4. Based on the numerical simulation, the ranking of effectiveness in total emission reduction was VIF (82.4%) > Reagent + HDPE (73.2%) > Reagent + Irrigation (43.0%) > Reagent (23.5%) > Deep + HDPE (19.3%) > HOM (17.6%) > Deep (13.0%) > Irrigation (11.9%) > HDPE (5.8%). The order for pest control efficacy suggests, VIF had the highest pest control efficacy, followed by Deep + HDPE, Irrigation, Reagent + Irrigation, HDPE, Deep, Reagent + HDPE, Reagent, and HOM. Therefore, VIF is the optimal method disregarding

  2. Incorporation of bactericidal poly-acrylic acid modified copper iodide particles into adhesive resins.

    Science.gov (United States)

    Sabatini, Camila; Mennito, Anthony S; Wolf, Bethany J; Pashley, David H; Renné, Walter G

    2015-05-01

    This study aimed to investigate incorporation of polyacrylic acid (PAA) coated copper iodide (CuI) nanoparticles into dental adhesives, and to evaluate for the first time, their antibacterial properties, bond strength and cytotoxicity. PAA-CuI nanoparticles were synthesized and incorporated into commercially available adhesives Optibond XTR (1.0mg/ml) and XP Bond (0.5 and 1.0mg/ml). The antibacterial properties of experimental and control specimens were evaluated (n=8), after ageing for 18h or 1 year, against Streptococcus mutans (1×10(8)cells/ml). Bond strength to human dentine of the control and experimental adhesives was evaluated by shear bond strength (n=10). For cytotoxicity evaluation, HGF cells were cultured with gingival fibroblast media and exposed to control and experimental adhesive blends (n=3). An MTT cell viability assay was used to assess cell metabolic function. A one-way analysis of variance followed by Tukey's test was used for data analysis. Significantly greater antibacterial properties were demonstrated for PAA-CuI containing adhesives after ageing for 18h or 1 year relative to all control groups. A reduction in Streptococcus mutans viable cell count of 99.99%, 99.99% and 79.65% was shown for XP Bond - 0.5mg/ml, XP Bond - 1.0mg/ml and Optibond XTR - 1.0mg/ml PAA-CuI after ageing for 18h, and 99.99% for both XP Bond - 0.5mg/ml and XP Bond - 1.0mg/ml PAA-CuI after ageing for 1 year. No significant variations in shear bond strength or cytotoxicity were detected between the experimental resins and their corresponding controls. PAA-CuI nanoparticles are an effective additive to adhesive blends as it renders them antibacterial without adversely affecting their bond strength or cytotoxicity. The incorporation of PAA-coated copper iodide particles into adhesive resins renders the adhesive antibacterial to S. mutans for at least 1 year in vitro. This may prevent or delay bacterial invasion and the consequent development of caries lesions if the

  3. Modulation of Sodium/Iodide Symporter Expression in the Salivary Gland

    Science.gov (United States)

    La Perle, Krista M.D.; Kim, Dong Chul; Hall, Nathan C.; Bobbey, Adam; Shen, Daniel H.; Nagy, Rebecca S.; Wakely, Paul E.; Lehman, Amy; Jarjoura, David

    2013-01-01

    Background Physiologic iodide-uptake, mediated by the sodium/iodide symporter (NIS), in the salivary gland confers its susceptibility to radioactive iodine–induced damage following 131I treatment of thyroid cancer. Subsequent quality of life for thyroid cancer survivors can be decreased due to recurrent sialoadenitis and persistent xerostomia. NIS expression at the three principal salivary duct components in various pathological conditions was examined to better our understanding of NIS modulation in the salivary gland. Methods NIS expression was evaluated by immunohistochemistry in human salivary gland tissue microarrays constructed of normal, inflamed, and neoplastic salivary tissue cores. Cumulative 123I radioactivity reflecting the combination of NIS activity with clearance of saliva secretion in submandibular and parotid salivary glands was evaluated by single-photon emission computed tomography/computed tomography imaging 24 hours after 123I administration in 50 thyroid cancer patients. Results NIS is highly expressed in the basolateral membranes of the majority of striated ducts, yet weakly expressed in few intercalated and excretory duct cells. The ratio of 123I accumulation between parotid and submandibular glands is 2.38±0.19. However, the corresponding ratio of 123I accumulation normalized by volume of interest is 1.19±0.06. The percentage of NIS-positive striated duct cells in submandibular salivary glands was statistically greater than in parotid salivary glands, suggesting a higher clearance rate of saliva secretion in submandibular salivary glands. NIS expression in striated ducts was heterogeneously decreased or absent in sialoadenitis. Most ductal salivary gland tumors did not express NIS. However, Warthin's tumors of striated duct origin exhibited consistent and intense NIS staining, corresponding with radioactive iodine uptake. Conclusions NIS expression is tightly modulated during the transition of intercalated to striated ducts and striated

  4. The effect of temperature on radiolysis of iodide ion diluted aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Gorbovitskaya, T.; Tiliks, J. [Latvia Univ., Lab. of Radiation Chemistry, Riga (Latvia)

    1996-12-01

    To investigate the radiolysis of iodine containing aqueous solutions a flow type facility (ITF) has a possibility to irradiate aqueous solutions in the steel vessel with {sup 60}Co {gamma}-rays and continuously (on line) to analyze the products of radiolysis both in liquid and in gaseous phases. By means of ITF the formation of I{sub ox} (I{sub 2} + I{sub 3}{sup -} + HOI), IO{sub 3}{sup -}, H{sub 2}O{sub 2} was studied in 10{sup -5} - 10{sup -3} mol/dm{sup 3} CsI aqueous solutions by their radiolysis at dose rate 4.5 kGv/h for six hours in region of temperatures from 313 to 404 K. Some experiments in glass ampoules were also performed. The steady-state concentrations of I{sub ox} and IO{sub 3}{sup -} decreased with increasing temperature as linear function of inverted temperature. The effect decreased with decreasing concentration of iodide ion. As the result, at high temperatures (T{>=}380 K) the steady-state concentration of I{sub ox} does not depend essentially on the iodide ion initial concentration. Molecular iodine (I{sub 2}) released from the solution was the main radiolysis product in gaseous phase. Its steady-state concentration increased with increasing temperature because of iodine solubility in the water and decreased at the same time because the radiolytic iodine concentrations decreased. Therefore the most volatility of irradiated 10{sup -3} and 10{sup -4}M CsI solutions was observed at the temperature about 350 K. The volatility of 10{sup -5}M solutions gradually decreased with increasing temperature. The experimental data were explained on the base of the hypothesis that the reaction between I{sub 2} and radiolytic H{sub 2}O{sub 2} was the limit one determining the temperature dependence of I{sub ox} and IO{sub 3}{sup -}steady-state concentrations. Its activation energy was estimated to be 27,5 kcal.mol{sup -1}. The temperature dependence for reaction (IO{sup -} + H{sub 2}O{sub 2}) was also estimated. (author) 8 figs., 1 tab., 17 refs.

  5. The pseudosymmetric structure of bis­(pentane-1,5-diaminium) iodide tris­(triiodide)

    Science.gov (United States)

    van Megen, Martin; Reiss, Guido J.

    2012-01-01

    The asymmetric unit of the title compound, [H3N(CH2)5NH3]2I[I3]3 or 2C5H16N2 2+·3I3 −·I−, consists of two crystallographically independent pentane-1,5-diaminium dications and two triiodide anions in general positions besides two additional triiodide and two iodide anions located on twofold axes. The compound crystallizes in the centrosymmetric monoclinic space group P2/n. The structure refinement was handicapped by the pseudosymmetry (pseudo-centering) of the structure and by twinning. The crystal structure is composed of two alternate layers, which differ in their arrangement of the pentane-1,5-diaminium dications and the iodide/triiodide anions and which are connected via weak to medium–strong N—H⋯I hydrogen bonds, constructing a complex hydrogen-bonded network. PMID:22590232

  6. High Photon-to-Current Conversion in Solar Cells Based on Light-Absorbing Silver Bismuth Iodide.

    Science.gov (United States)

    Zhu, Huimin; Pan, Mingao; Johansson, Malin B; Johansson, Erik M J

    2017-06-22

    Here, a lead-free silver bismuth iodide (AgI/BiI 3 ) with a crystal structure with space group R3‾ m is investigated for use in solar cells. Devices based on the silver bismuth iodide deposited from solution on top of TiO 2 and the conducting polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) as a hole-transport layer are prepared and the photovoltaic performance is very promising with a power conversion efficiency over 2 %, which is higher than the performance of previously reported bismuth-halide materials for solar cells. Photocurrent generation is observed between 350 and 700 nm, and the maximum external quantum efficiency is around 45 %. The results are compared to solar cells based on the previously reported material AgBi 2 I 7 , and we observe a clearly higher performance for the devices with the new silver and bismuth iodides composition and different crystal structure. The X-ray diffraction spectrum of the most efficient silver bismuth iodide material shows a hexagonal crystal structure with space group R3‾ m, and from the light absorption spectrum we obtain an indirect band gap energy of 1.62 eV and a direct band gap energy of 1.85 eV. This report shows the possibility for finding new structures of metal-halides efficient in solar cells and points out new directions for further exploration of lead-free metal-halide solar cells. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  7. Dual-expressing adenoviral vectors encoding the sodium iodide symporter for use in noninvasive radiological imaging of therapeutic gene transfer

    Energy Technology Data Exchange (ETDEWEB)

    Niu Gang [Free Radical and Radiation Biology Program, The University of Iowa, Iowa City, IA 52242 (United States); Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242 (United States); Anderson, Richard D. [ViraQuest Inc., North Liberty, IA 52317 (United States); Madsen, Mark T. [Department of Radiology, University of Iowa, Iowa City, IA 52242 (United States); Carver College of Medicine and Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA 52242 (United States); Graham, Michael M. [Department of Radiology, University of Iowa, Iowa City, IA 52242 (United States); Carver College of Medicine and Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA 52242 (United States); Oberley, Larry W. [Free Radical and Radiation Biology Program, University of Iowa, Iowa City, IA 52242 (United States); Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242 (United States); Carver College of Medicine and Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA 52242 (United States); Domann, Frederick E. [Free Radical and Radiation Biology Program, University of Iowa, Iowa City, IA 52242 (United States) and Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242 (United States) and Carver College of Medicine and Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA 52242 (United States)]. E-mail: frederick-domann@uiowa.edu

    2006-04-15

    Introduction: Noninvasive analysis of therapeutic transgene expression is important for the development of clinical translational gene therapy strategies against cancer. To image p53 and MnSOD gene transfer noninvasively, we used radiologically detectable dual-expressing adenoviral vectors with the human sodium iodide symporter (hNIS) as the reporter gene. Methods: Dual-expressing adenoviral vectors were constructed with hNIS cloned into E3 region and therapeutic genes, either MnSOD or p53, recombined into the E1 region. Steady-state mRNA levels of hNIS were evaluated by real-time polymerase chain reaction. hNIS function was determined by iodide uptake assay and MnSOD, and p53 protein levels were assessed by Western blots. Results: {sup 125}I{sup -} accumulation resulting from hNIS expression in both Ad-p53-hNIS- and Ad-MnSOD-hNIS-infected MDA-MB-435 cells could be visualized clearly on phosphorimaging autoradiograph. Iodide accumulation increased with increasing adenovirus titer, and there was a linear correlation between iodide uptake and dose. p53 and MnSOD protein levels increased as a function of adenovirus titer, and there was a direct positive correlation between p53 and MnSOD expression and hNIS function. P53 and MnSOD overexpression inhibited cell growth in the dual-expressing adenoviral vector-infected cells. Conclusions: Radiological detection of hNIS derived from dual-expressing adenoviral vectors is a highly effective method to monitor therapeutic gene transfer and expression in a noninvasive manner.

  8. 2-Oxo-2,3-dihydro-1H-imidazo[1,2-a]pyridinium iodide

    Directory of Open Access Journals (Sweden)

    Yong Nie

    2010-03-01

    Full Text Available In the title compound, C7H7N2O+·I−, the carbonyl C and O atoms of the cation and the iodide ion are situated on mirror planes. The mean plane of the imidazo[1,2-d]pyridinium cation is perpendicular to the mirror plane as a consequence of the disorder of the cation over two opposite orientations of equal occupancy. In the crystal, N—H...I interactions are present.

  9. Broad-Spectrum Antimicrobial Effects of Photocatalysis Using Titanium Dioxide Nanoparticles Are Strongly Potentiated by Addition of Potassium Iodide.

    Science.gov (United States)

    Huang, Ying-Ying; Choi, Hwanjun; Kushida, Yu; Bhayana, Brijesh; Wang, Yuguang; Hamblin, Michael R

    2016-09-01

    Photocatalysis describes the excitation of titanium dioxide nanoparticles (a wide-band gap semiconductor) by UVA light to produce reactive oxygen species (ROS) that can destroy many organic molecules. This photocatalysis process is used for environmental remediation, while antimicrobial photocatalysis can kill many classes of microorganisms and can be used to sterilize water and surfaces and possibly to treat infections. Here we show that addition of the nontoxic inorganic salt potassium iodide to TiO2 (P25) excited by UVA potentiated the killing of Gram-positive bacteria, Gram-negative bacteria, and fungi by up to 6 logs. The microbial killing depended on the concentration of TiO2, the fluence of UVA light, and the concentration of KI (the best effect was at 100 mM). There was formation of long-lived antimicrobial species (probably hypoiodite and iodine) in the reaction mixture (detected by adding bacteria after light), but short-lived antibacterial reactive species (bacteria present during light) produced more killing. Fluorescent probes for ROS (hydroxyl radical and singlet oxygen) were quenched by iodide. Tri-iodide (which has a peak at 350 nm and a blue product with starch) was produced by TiO2-UVA-KI but was much reduced when methicillin-resistant Staphylococcus aureus (MRSA) cells were also present. The model tyrosine substrate N-acetyl tyrosine ethyl ester was iodinated in a light dose-dependent manner. We conclude that UVA-excited TiO2 in the presence of iodide produces reactive iodine intermediates during illumination that kill microbial cells and long-lived oxidized iodine products that kill after light has ended. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  10. FEASIBILITY STUDY FOR POTASSIUM IODIDE (KI) DISTRIBUTION IN NEW YORK CITY.

    Energy Technology Data Exchange (ETDEWEB)

    MOSS, STEVEN

    2005-04-29

    The New York City Department of Health and Mental Hygiene (DOHMH), Bureau of Environmental Science and Engineering, Office of Radiological Health (ORH) [as the primary local technical consultant in the event of a radiological or nuclear incident within the boundaries of New York City] requested the assistance of Brookhaven National Laboratory (BNL) with the development of a Feasibility Study for Potassium Iodide (KI) distribution in the unlikely event of a significant release of radioactive iodine in or near New York City. Brookhaven National Laboratory had previously provided support for New York City with the development of the radiological/nuclear portions of its All Hazards Emergency Response Plans. The work is funded by Medical and Health Research Association (MHRA) of New York City, Inc., under a work grant by the Federal Centers for Disease Control (CDC) for Public Health Preparedness and Response for Bioterrorism. This report is part of the result of that effort. The conclusions of this report are that: (1) There is no credible radiological scenario that would prompt the need for large segments of the general population of New York City to take KI as a result of a projected plume exposure to radioiodine reaching even the lowest threshold of 5 rem to the thyroid; and (2) KI should be stockpiled in amounts and locations sufficient for use by first responders/emergency responders in response to any localized release of radioiodine.

  11. The effect of tanespimycin (17-AAG) on radioiodine accumulation in sodium iodide symporter expressing cells

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Kyoung Hyun; Youn, Hyewon; Song, Myung Geun; Lee, Dong Soo; Chung, June Key [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2012-12-15

    The heat shock protein 90 inhibitor, tanespimycin, is an anticancer agent known to increase iodine accumulation in normal and cancerous thyroid cells. Iodine accumulation is regulated by membrane proteins such as sodium iodide sym porter (NIS) and pendrin (PDS), and thus we attempted to characterize the effects of tanespimycin on those genes. Cells were incubated with tanespimycin in order to evaluate {sup 125}I accumulation and efflux ability. Radioiodine uptake and efflux were measured by a gamma counter and normalized by protein amount. RT PCR were performed to measure the level of gene expression. After tanespimycin treatment, {sup 125}uptake was in creased by {approx}2.5 fold in FRTL 5, hNIS ARO. and hNIS MDA MB 231 cells, but no changes were detected in the hNIS HeLa cells. Tanespimycin significantly reduced the radioiodine efflux rate only in the FRTL 5 cell. in the FRTL 5 and hNIS ARO cells, PDS mRNA levels were markedly reduced; the only other observed alteration in the levels of NIS mRNA after tanespimtycin treatment was an observed increase in the h hNIS ARO cells. These results indicate that cellular responses against tanespimycin treatment differed between the normal rat thyroid cells and human cancer cells, and the reduction in the {sup 125I} efflux rate by tanespimycin in the normal rat thyroid cells might be attributable to reduced PDS gene expression.

  12. The kinetics of iodide oxidation by the manganese oxide mineral birnessite

    Science.gov (United States)

    Fox, P.M.; Davis, J.A.; Luther, G. W.

    2009-01-01

    The kinetics of iodide (I-) and molecular iodine (I2) oxidation by the manganese oxide mineral birnessite (??-MnO2) was investigated over the pH range 4.5-6.25. I- oxidation to iodate (IO3-) proceeded as a two-step reaction through an I2 intermediate. The rate of the reaction varied with both pH and birnessite concentration, with faster oxidation occurring at lower pH and higher birnessite concentration. The disappearance of I- from solution was first order with respect to I- concentration, pH, and birnessite concentration, such that -d[I-]/dt = k[I-][H+][MnO2], where k, the third order rate constant, is equal to 1.08 ?? 0.06 ?? 107 M-2 h-1. The data are consistent with the formation of an inner sphere I- surface complex as the first step of the reaction, and the adsorption of I- exhibited significant pH dependence. Both I2, and to a lesser extent, IO3- sorbed to birnessite. The results indicate that iodine transport in mildly acidic groundwater systems may not be conservative. Because of the higher adsorption of the oxidized I species I2 and IO3-, as well as the biophilic nature of I2, redox transformations of iodine must be taken into account when predicting I transport in aquifers and watersheds.

  13. Crystal structure of 4-{2-[4-(dimethylaminophenyl]diazen-1-yl}-1-methylpyridinium iodide

    Directory of Open Access Journals (Sweden)

    Katherine Chulvi

    2015-12-01

    Full Text Available The molecular geometry of the ionic title compound, C14H17N4+·I− or DAZOP+·I−, is essentially featureless. Regarding the crystal structure, in addition to the obvious cation–anion Coulombic interactions, the packing is mostly directed by non-covalent interactions involving both ring systems, as well as the iodide anion. It consists of cationic molecules aligned along [101] and disposed in an antiparallel fashion while linked into π-bonded dimeric entities by a stacking contact involving symmetry-related phenyl rings, with a centroid–centroid distance of 3.468 (3 Å and a slippage of 0.951 Å. The dimers are, in addition, sustained by a number of C—H...I and I...π (I...centroid = 3.876 Å interactions involving the anion. Finally, interdimeric contacts are of the C—H...I and C—H...π types.

  14. Aluminium effects on thyroid gland function: iodide uptake, hormone biosynthesis and secretion.

    Science.gov (United States)

    Orihuela, Daniel

    2011-11-01

    The effects of aluminium (Al) on thyroid function were evaluated in adult Wistar rats intraperitoneally (i.p) injected with 7 mg Al (as lactate)/kg body weight (b.w) per day during a six week period. The time-course kinetics of Na(125)I (3 μCi per 100 g b.w, i.p) was analysed by measuring gamma-radioactivity of thyroid, serum, serum protein precipitate and bile, at times ranging from 2 to 96 h post-dosing. In Al-treated group the (125)I(-) thyroid uptake at 24 h (15,840 ± 570 vs. 18,030 ± 630 dpm/mg, Pthyroid tissue were increased in Al-treated rats. The serum concentrations of total thyroxine (T4, 3.78 ± 0.14 vs. 4.68 ± 0.12 μg/dL, Pthyroid iodide uptake and hormones secretion by a mechanism involving the induction of an oxidative stress state, however, these changes could be managed by the hypothalamus-pituitary-thyroid endocrine axis. We can conclude that in adult rats the Al would not act as a thyroid disruptor. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Efficient methylammonium lead iodide perovskite solar cells with active layers from 300 to 900 nm

    Energy Technology Data Exchange (ETDEWEB)

    Momblona, C.; Malinkiewicz, O.; Soriano, A.; Gil-Escrig, L.; Bandiello, E.; Scheepers, M.; Bolink, H. J., E-mail: henk.bolink@uv.es [Instituto de Ciencia Molecular, Universidad de Valencia, C/Catedrático J. Beltrán 2, 46980 Paterna, Valencia (Spain); Roldán-Carmona, C. [Instituto de Ciencia Molecular, Universidad de Valencia, C/Catedrático J. Beltrán 2, 46980 Paterna, Valencia (Spain); Department of Physical Chemistry and Applied Thermodynamics, University of Córdoba, Campus Rabanales, Ed. C3, 14014, Córdoba (Spain); Edri, E. [Department of Materials and Interfaces, Weizmann Institute of Science, Herzl St. 34, Rehovot 76100 (Israel)

    2014-08-01

    Efficient methylammonium lead iodide perovskite-based solar cells have been prepared in which the perovskite layer is sandwiched in between two organic charge transporting layers that block holes and electrons, respectively. This configuration leads to stable and reproducible devices that do not suffer from strong hysteresis effects and when optimized lead to efficiencies close to 15%. The perovskite layer is formed by using a dual-source thermal evaporation method, whereas the organic layers are processed from solution. The dual-source thermal evaporation method leads to smooth films and allows for high precision thickness variations. Devices were prepared with perovskite layer thicknesses ranging from 160 to 900 nm. The short-circuit current observed for these devices increased with increasing perovskite layer thickness. The main parameter that decreases with increasing perovskite layer thickness is the fill factor and as a result optimum device performance is obtained for perovskite layer thickness around 300 nm. However, here we demonstrate that with a slightly oxidized electron blocking layer the fill factor for the solar cells with a perovskite layer thickness of 900 nm increases to the same values as for the devices with thin perovskite layers. As a result the power conversion efficiencies for the cells with 300 and 900 nm are very similar, 12.7% and 12%, respectively.

  16. Low band gap polymeric solar cells using solution-processable copper iodide as hole transporting layer

    Science.gov (United States)

    Chaudhary, Neeraj; Kesari, J. P.; Chaudhary, Rajiv; Patra, Asit

    2016-08-01

    In the present work, we have shown the performance of solution-processable copper iodide (CuI) as an alternative hole transporting layer (HTL) for polymeric solar cells. Optical spectra of the CuI thin film reveal highly transparent and practically no absorption in the range vis-NIR region (450-1110 nm). X-ray diffraction (XRD) patterns of CuI exhibits as a p-type semiconductor as well as crystalline nature. The photovoltaic devices were fabricated using PCDTBT and PTB7 as donor materials blended with PC71BM as an acceptor material. The power conversion efficiencies (PCEs) based on CuI as an HTL have been achieved to up to 3.04% and 4.48% for PCDTBT and PTB7 based donor materials respectively with a configuration based on ITO/CuI(40 nm)/active layer (60 nm)/Al (120 nm). This study clearly indicated that the devices made with CuI as an HTL showed superior performance than the device fabricated from PEDOT:PSS layer as an HTL. Morphological characterization of the HTL using scanning electron microscopy (SEM) and atomic force microscope (AFM) were carried for better understanding.

  17. Disappearance of the Superionic Phase Transition in Sub-5 nm Silver Iodide Nanoparticles.

    Science.gov (United States)

    Yamamoto, Takayuki; Kobayashi, Hirokazu; Kumara, Loku Singgappulige Rosantha; Sakata, Osami; Nitta, Kiyofumi; Uruga, Tomoya; Kitagawa, Hiroshi

    2017-09-13

    Bulk silver iodide (AgI) is known to show a phase transition from the poorly conducting β/γ-phases into the superionic conducting α-phase at 147 °C. Its transition temperature decreases with decreasing the size of AgI, and the α-phase exists stably at 37 °C in AgI nanoparticles with a diameter of 6.3 nm. In this Letter, we investigated the atomic configuration, the phase transition behavior, and the ionic conductivity of AgI nanoparticles with a diameter of 3.0 nm. The combination of pair distribution function (PDF) analysis and reverse Monte Carlo (RMC) modeling based on high-energy X-ray diffraction (XRD) revealed for the first time that they formed the β/γ-phases with atomic disorder. The results of extended X-ray absorption fine structure (EXAFS) analysis, differential scanning calorimetry (DSC), and AC impedance spectroscopy demonstrated that they did not exhibit the superionic phase transition and their ionic conductivity was lower than that of crystalline AgI. The disappearance of the superionic phase transition and low ionic conductivity in the very small AgI nanoparticles originates from their small size and disordered structure.

  18. Whispering gallery mode lasing from hexagonal shaped layered lead iodide crystals.

    Science.gov (United States)

    Liu, Xinfeng; Ha, Son Tung; Zhang, Qing; de la Mata, Maria; Magen, César; Arbiol, Jordi; Sum, Tze Chien; Xiong, Qihua

    2015-01-27

    We report on the synthesis and optical gain properties of regularly shaped lead iodide (PbI2) platelets with thickness ranging from 10-500 nm synthesized by chemical vapor deposition methods. The as-prepared single crystalline platelets exhibit a near band edge emission of ∼ 500 nm. Whispering gallery mode (WGM) lasing from individual hexagonal shaped PbI2 platelets is demonstrated in the temperature-range of 77-210 K, where the lasing modes are supported by platelets as thin as 45 nm. The finite-difference time-domain simulation and the edge-length dependent threshold confirm the planar WGM lasing mechanism in such hexagonal shaped PbI2 platelet. Through a comprehensive study of power-dependent photoluminescence (PL) and time-resolved PL spectroscopy, we ascribe the WGM lasing to be biexcitonic in nature. Moreover, for different thicknesses of platelet, the lowest lasing threshold occurs in platelets of ∼ 120 nm, which attributes to the formation of a good Fabry-Pérot resonance cavity in the vertical direction between the top and bottom platelet surfaces that enhances the reflection. Our present study demonstrates the feasibility of planar light sources based on layered semiconductor materials and that their thickness-dependent threshold characteristic is beneficial for the optimization of layered material based optoelectronic devices.

  19. FUV quantum efficiency degradation of cesium iodide photocathodes caused by exposure to thermal atomic oxygen

    Science.gov (United States)

    McPhate, Jason; Anne, Joshi; Bacinski, John; Banks, Bruce; Cates, Carey; Christensen, Paul; Cruden, Brett; Dunham, Larry; Graham, Eric; Hughes, David; Kimble, Randy; Lupie, Olivia; Niedner, Malcolm; Osterman, Steven; Penton, Steven; Proffitt, Charles; Pugel, Diane; Siegmund, Oswald; Wheeler, Thomas

    2011-09-01

    The color dependence of the measured decline of the on-orbit sensitivity of the FUV channel of the HST Cosmic Origins Spectrograph (HST-COS) indicated the principal loss mechanism to be degradation of the cesium iodide (CsI) photocathode of the open-faced FUV detector. A possible cause of this degradation is contamination by atomic oxygen (AO), prompting an investigation of the interaction of AO with CsI. To address this question, opaque CsI photocathodes were deposited on stainless steel substrates employing the same deposition techniques and parameters used for the photocathodes of the HST-COS FUV detector. The as-deposited FUV quantum efficiency of these photocathodes was measured in the 117-174 nm range. Several of the photocathodes were exposed to varying levels of thermalized, atomic oxygen (AO) fluence (produced via an RF plasma). The post AO exposure QE's were measured and the degradation of sensitivity versus wavelength and AO fluence are presented.

  20. Highly spin-polarized deuterium atoms from the UV dissociation of Deuterium Iodide

    CERN Document Server

    Sofikitis, D; Koumarianou, G; Jiang, H; Bougas, L; Samartzis, P C; Andreev, A; Rakitzis, T P

    2016-01-01

    Hyperpolarisation of deuterium (D) and tritium (T) nuclear spins increases the D-T fusion reaction rate by ~50%, thus lowering the breakeven limit for the achievement of self-sustained fusion, and controls the emission direction of the reaction products for improved reactor efficiency. However, the important D-D polarization-dependent fusion reaction has not yet been measured, due to the low density of conventional polarized deuterium beams of ~10$^{12}$ cm$^{-3}$, limited by collisions on the ms-timescale of production. Here we demonstrate that hyperpolarised D atoms are produced by the 270 nm photodissociation of deuterium iodide (DI), yielding ~60% nuclear D polarization after ~1.6 ns, ~10$^6$ times faster than conventional methods, allowing collision-limited densities of ~10$^{18}$ cm$^{-3}$. Such ultrahigh densities of polarized D atoms open the way for the study of high-signal polarized D-D reactions. We discuss the possibility of the production of high-density pulsed polarized beams, and of polarized D...

  1. Mercuric iodide room-temperature array detectors for gamma-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Patt, B. [Xsirius, Inc, Camarillo, CA (United States)

    1994-11-15

    Significant progress has been made recently in the development of mercuric iodide detector arrays for gamma-ray imaging, making real the possibility of constructing high-performance small, light-weight, portable gamma-ray imaging systems. New techniques have been applied in detector fabrication and then low noise electronics which have produced pixel arrays with high-energy resolution, high spatial resolution, high gamma stopping efficiency. Measurements of the energy resolution capability have been made on a 19-element protypical array. Pixel energy resolutions of 2.98% fwhm and 3.88% fwhm were obtained at 59 keV (241-Am) and 140-keV (99m-Tc), respectively. The pixel spectra for a 14-element section of the data is shown together with the composition of the overlapped individual pixel spectra. These techniques are now being applied to fabricate much larger arrays with thousands of pixels. Extension of these principles to imaging scenarios involving gamma-ray energies up to several hundred keV is also possible. This would enable imaging of the 208 keV and 375-414 keV 239-Pu and 240-Pu structures, as well as the 186 keV line of 235-U.

  2. Potassium Iodide-Functionalized Polyaniline Nanothin Film Chemiresistor for Ultrasensitive Ozone Gas Sensing

    Directory of Open Access Journals (Sweden)

    Sira Srinives

    2017-02-01

    Full Text Available Polyaniline (PANI nanostructures have been widely studied for their sensitivity to atmospheric pollutants at ambient conditions. We recently showed an effective way to electropolymerize a PANI nanothin film on prefabricated microelectrodes, and demonstrated its remarkable sensing performance to be comparable to that of a one-dimensional nanostructure, such as PANI nanowires. In this work, we report further progress in the application of the PANI nanothin film chemiresistive sensor for the detection of ozone (O3 by modifying the film with potassium iodide (KI. The KI-PANI sensor exhibited an excellent sensitivity to O3 (8–180 ppb O3 concentration rage with a limit of detection of 230 ppt O3, and exquisite selectivity against active chemicals such as nitrogen dioxide (NO2 and sulfur dioxide (SO2. The sensing mechanism of the sensor relied on iodometric chemistry of KI and O3, producing triiodide ( I 3 − that partially doped and increased electrical conductivity of the PANI film. The sensitivity and selectivity of the KI-functionalized PANI film demonstrates the potential use for KI-PANI-based O3 sensing devices in environmental monitoring and occupational safety.

  3. Optical Analysis of Ag-NPs Containing Methyl Ammonium Lead Tri-Iodide Thin Films

    Directory of Open Access Journals (Sweden)

    Cliff Orori Mosiori

    2017-09-01

    Full Text Available Methyl ammonium lead tri-iodide hybrid thin films were grown using solution technique. They were doped with silver nano-particles at different concentrations at concentrations of 0.05, 0.06, 0.07, 0.08, and 0.09 mM. Their reflectance and transmittance were recorded in the wavelength range 300–900 using UV-Vis double - beam spectrophotometer. Using these measurements, other optical parameters were simulated using scout software. The effect of silver nanoparticles was investigated. Results revealed that the thin films had highest transmittance of about 79 % as their band gap varied from 1.921–1.832 eV. Electrical conductivity varied from 1.4–1.6×105 S cm–1 while optical conductivity varied in the range of 0.3–0.6×1010 sec-1. They had a significantly low refractive index, suitable for optical applications within the range of 1.6–1.8. The extinction coefficient varied in the range as 1.0–1.7×10-5 while the absorption coefficient varied varies in the range of 2.1-4.2 cm- 1. It was concluded that the thin films were suitable for photonic device applications.

  4. Photoluminescence Blinking of Single-Crystal Methylammonium Lead Iodide Perovskite Nanorods Induced by Surface Traps

    Science.gov (United States)

    2016-01-01

    Photoluminescence (PL) of organometal halide perovskite materials reflects the charge dynamics inside of the material and thus contains important information for understanding the electro-optical properties of the material. Interpretation of PL blinking of methylammonium lead iodide (MAPbI3) nanostructures observed on polycrystalline samples remains puzzling owing to their intrinsic disordered nature. Here, we report a novel method for the synthesis of high-quality single-crystal MAPbI3 nanorods and demonstrate a single-crystal study on MAPbI3 PL blinking. At low excitation power densities, two-state blinking was found on individual nanorods with dimensions of several hundred nanometers. A super-resolution localization study on the blinking of individual nanorods showed that single crystals of several hundred nanometers emit and blink as a whole, without showing changes in the localization center over the crystal. Moreover, both the blinking ON and OFF times showed power-law distributions, indicating trapping–detrapping processes. This is further supported by the PL decay times of the individual nanorods, which were found to correlate with the ON/OFF states. Furthermore, a strong environmental dependence of the nanorod PL blinking was revealed by comparing the measurements in vacuum, nitrogen, and air, implying that traps locate close to crystal surfaces. We explain our observations by proposing surface charge traps that are likely related to under-coordinated lead ions and methylammonium vacancies to result in the PL blinking observed here. PMID:27617323

  5. Phonon-Electron Scattering Limits Free Charge Mobility in Methylammonium Lead Iodide Perovskites.

    Science.gov (United States)

    Karakus, Melike; Jensen, Søren A; D'Angelo, Francesco; Turchinovich, Dmitry; Bonn, Mischa; Cánovas, Enrique

    2015-12-17

    The nature of the photoconductivity in solution-processed films of methylammonium lead iodide perovskite is investigated by determining the variation of the photoconductive response with temperature. Ultrabroadband terahertz (THz) photoconductivity spectra in the 0.3-10 THz range can be reproduced well by a simple Drude-like response at room temperature, where free charge carrier motion is characterized by an average scattering time. The scattering time determined from Drude fits in the 0.3-2THz region increases from ∼4 fs at 300 K (tetragonal phase; mobility of ∼27 cm(2) V(-1) s(-1)) to almost ∼25 fs at 77 K (orthorhombic phase, mobility of ∼150 cm(2) V(-1) s(-1)). For the tetragonal phase (temperature range 150 < T < 300 K) the scattering time shows a ∼T(-3/2) dependence, approaching the theoretical limit for pure acoustic phonon (deformation potential) scattering. Hence, electron-phonon, rather than impurity scattering, sets the upper limit on free charge transport for this perovskite.

  6. Analysis of TPO gene in Turkish children with iodide organification defect: identification of a novel mutation.

    Science.gov (United States)

    Turkkahraman, Doga; Alper, Ozgul M; Pehlivanoglu, Suray; Aydin, Funda; Yildiz, Akin; Luleci, Guven; Akcurin, Sema; Bircan, Iffet

    2010-02-01

    The objective was to determine molecular genetic analysis of the TPO gene in Turkish children with iodide organification defect (IOD). Patients with a diagnosis of primary hypothyroidism were evaluated. Subjects having a definite diagnosis of autoimmune thyroiditis, thyroid gland dysplasia and, or iodine deficiency were excluded. A total of 10 patients from nine unrelated Turkish families, with an unknown etiology of hypothyroidism, and with a presumptive diagnosis of IOD were included in the study. A perchlorate discharge test (PDT) was performed to all subjects, and sequence analysis of TPO gene was applied in patients with a positive PDT. Five out of 10 patients have a total IOD, while the five remaining patients have a partial IOD according to PDT results. In two sisters, one has a partial and the other one has a total IOD a novel homozygous nonsense p.Q315X mutation was found in exon 8. Additionally, a previously known homozygous missense p.R314W mutation was detected in the same exon in another patient with a total IOD. No TPO gene mutation was detected in any of the seven remaining patients. Two different TPO gene mutations were found to be responsible for IOD in two unrelated Turkish families from the same ethnic background. More subjects should be screened for detecting the prevalence and spectrum profile of TPO mutations in our population that might be helpful for understanding the pathophysiology of congenital hypothyroidism.

  7. Characterization of highly crystalline lead iodide nanosheets prepared by room-temperature solution processing

    Science.gov (United States)

    Frisenda, Riccardo; Island, Joshua O.; Lado, Jose L.; Giovanelli, Emerson; Gant, Patricia; Nagler, Philipp; Bange, Sebastian; Lupton, John M.; Schüller, Christian; Molina-Mendoza, Aday J.; Aballe, Lucia; Foerster, Michael; Korn, Tobias; Niño, Miguel Angel; Perez de Lara, David; Pérez, Emilio M.; Fernandéz-Rossier, Joaquín; Castellanos-Gomez, Andres

    2017-11-01

    Two-dimensional (2D) semiconducting materials are particularly appealing for many applications. Although theory predicts a large number of 2D materials, experimentally only a few of these materials have been identified and characterized comprehensively in the ultrathin limit. Lead iodide, which belongs to the transition metal halides family and has a direct bandgap in the visible spectrum, has been known for a long time and has been well characterized in its bulk form. Nevertheless, studies of this material in the nanometer thickness regime are rather scarce. In this article we demonstrate an easy way to synthesize ultrathin, highly crystalline flakes of PbI2 by precipitation from a solution in water. We thoroughly characterize the produced thin flakes with different techniques ranging from optical and Raman spectroscopy to temperature-dependent photoluminescence and electron microscopy. We compare the results to ab initio calculations of the band structure of the material. Finally, we fabricate photodetectors based on PbI2 and study their optoelectronic properties.

  8. Fluctuations and Anharmonicity in Lead Iodide Perovskites from Molecular Dynamics Supercell Simulationss

    KAUST Repository

    Carignano, Marcelo Andrés

    2017-09-05

    We present a systematic study based on first principles molecular dynamics simulations of lead iodide perovskites with three different cations, including methylammonium (MA), formamidinium (FA) and cesium. Using the high temperature perovskite structure as a reference, we investigate the instabilities that develop as the material is cooled down to 370 K. All three perovskites display anharmonicity in the motion of the iodine atoms, with the stronger effect observed for the MAPbI$_3$ and CsPbI$_3$. At high temperature, this behavior can be traced back to the reduced effective size of the Cs$^+$ and MA$^+$ cations. MAPbI$_3$ undergoes a spontaneous phase transition within our simulation model driven by the dipolar interaction between neighboring MA cations as the temperature is decreased from 450 K. The reverse transformation from tetragonal to cubic is also monitored through the large distribution of the octahedral tilting angles accompanied by an increase in the anharmonicity of the iodine atoms motion. Both MA and FA hybrid perovskites show a strong coupling between the molecular orientations and the local lattice deformations, suggesting mixed order-disorder/displacive characters of the high temperature phase transitions.

  9. Thickness dependence of structural and optical properties of cadmium iodide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Yahia, I.S. [Department of Physics, Faculty of Science, King Khalid University, P.O. Box 9004, Abha (Saudi Arabia); Centre of Nanotechnology, King AbdulAziz University, Jeddah (Saudi Arabia); Shapaan, M. [Department of Physics, Faculty of Science, Al-Azahar University, Cairo (Egypt); Ismail, Yasser A.M.; Aboraia, A.M. [Department of Physics, Faculty of Science, Al-Azahar University, Assiut 71542 (Egypt); Shaaban, E.R., E-mail: esamramadan2008@yahoo.com [Department of Physics, Faculty of Science, Al-Azahar University, Assiut 71542 (Egypt)

    2015-07-05

    Highlights: • Different thicknesses of CdI{sub 2} films were prepared. • Both crystallite size and microstrain of the films has been determined. • The room temperature reflectance and transmittance data are analyzed. • The refractive index and energy gap are determined. - Abstract: Structural and optical properties as a function of film thickness have been studied for the thermally evaporated cadmium iodide (CdI{sub 2}) films. According to XRD structure, the thickness of investigated films extends from 272 to 696 nm, showing hexagonal structure and good c-axis alignment normal to glass substrate plane. Both of crystallite size and lattice strain have been determined in terms of Voight method of the main peak. The optical constants, refractive index (n), and extinction coefficient (k) have been determined using envelope method. The optical absorption data indicates an allowed direct inter – band transition near the absorption edge with an optical energy gap that decreases continuously from 3.572 to 3.767 eV. Both of optical constants and energy gap show thickness dependence that can be explained in terms of structure parameters, crystallite size, and lattice strain.

  10. Radio-iodide uptake by modified poly (glycidyl methacrylate) as anion exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Othman, Sameh H. [Atomic Energy Authority, Cairo (Egypt). Nuclear Research Center; Atomic Energy Authority, Cairo (Egypt). Second Research Reactor; Elbarbary, Ahmed M. [Atomic Energy Authority, Cairo (Egypt). Radiation Research of Polymer Chemistry Dept.; Rashad, Ghada; Fasih, T.W. [Atomic Energy Authority, Cairo (Egypt). Hot Laboratories Center

    2017-03-01

    Poly(glycidyl methacrylate) (PGMA) microspheres were prepared by radiation induced polymerization of glycidyl methacrylate (GMA) monomer. The factors affecting the degree of polymerization and yield (%) of PGMA such as type of solvent, monomer concentration, and irradiation dose were investigated. It was found that the PGMA yield (%) increases with increasing monomer concentration up to 50% and absorbed dose of 5 kGy. The resulting PGMA containing the epoxy group was chemically modified by hydroxyl amine to act as anion-exchange resin for uptake of {sup 131}I{sup -} ions. The modified PGMA (MPGMA) was characterized by Fourier transform infrared (FT-IR) spectrophotometer, thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM). I-131 is produced from the fission of U-235 with low-enrichment uranium (LEU) targets in the Egyptian Second Research Reactor (ETRR-2). Separation of iodide from the radioactive solution by batchwise and column techniques was employed to determine the adsorption capacity of the MPGMA. Quality control of {sup 131}I product solution and radiochemical purity was examined by using the ascending paper chromatography method. The uptake behavior of MPGMA towards {sup 131}I{sup -} ions were studied at different experimental conditions and achieved by X-ray fluorescence (XRF). The synthesized MPGMA showed good results as anion-exchange and an effective adsorbent for uptaking {sup 131}I{sup -} ions.

  11. Experimental and analytical study on cesium iodide behavior in piping in wave experiment

    Energy Technology Data Exchange (ETDEWEB)

    Hidaka, A.; Igarashi, M.; Hashimoto, K.; Sugimoto, J. [Japan Atomic Energy Research Inst., Dep. of Reactor Safety Research, Tokai-mura (Japan); Yoshino, T. [Toshiba Advanced System Corp., Isago Kawasaki-ku (Japan)

    1996-12-01

    The WAVE (Wide range Aerosol model VErification) experiments have been performed at JAERI to investigate cesium iodide (CsI) deposition onto an inner surface of piping wall under typical severe accident conditions. The test facility consists of a dish containing CsI powder, electrical heaters and a straight pipe of 1.5 m in length with diameter of 0.042m. Nitrogen gas and superheated steam were injected into the pipe to carry the vaporized CsI and to simulate the thermohydraulic condition for the PWR hot-leg inlet. Analyses of the experiments have been conducted with a three-dimensional thermohydraulic code, SPRAC and the radionuclide behavior analysis codes, ART and VICTORIA. A clear difference was found in the deposition behavior between nitrogen and steam conditions as carrier gases. For nitrogen gas, the analyses well reproduced the experimental results by closely coupling the CsI behavior and the detailed thermohydraulic analyses. For steam carrier gas, on the contrary, the experimental results could not be well reproduced without the use of larger aerosol size. Since the observed enhancement of aerosol size in superheated steam cannot be explained by existing models, it is necessary to further investigate this mechanisms by experiment and analysis. (author) 34 figs., 23 refs.

  12. Comparative mammalian cell cytotoxicity of wastewater with elevated bromide and iodide after chlorination, chloramination, or ozonation.

    Science.gov (United States)

    Dong, Shengkun; Nguyen, Thanh H; Plewa, Michael J

    2017-08-01

    Recycling wastewater is becoming more common as communities around the world try to better control their water resources against an increased frequency of either prolonged droughts or intense flooding. For communities in coastal areas, wastewaters may contain elevated levels of bromide (Br-) and iodide (I-) from seawater intrusion or high mineral content of source waters. Disinfection of such wastewater is mandatory to prevent the spread of pathogens, however little is known about the toxicity of wastewater after disinfection in the presence of Br- and I-. In this study we compared the induction of chronic cytotoxicity in mammalian cells in samples of municipal secondary wastewater effluent amended with elevated levels of Br-/I- after disinfection by chlorine, chloramines or ozone to identify which disinfection process generated wastewater with the lowest level of adverse biological response. Chlorination increased mammalian cell cytotoxicity by 5 times as compared to non-disinfected controls. Chloramination produced disinfected wastewater that expressed 6.3 times more cytotoxicity than the non-disinfected controls and was 1.3 times more cytotoxic than the chlorinated samples. Ozonation produced wastewater with cytotoxicity comparable to the non-disinfected controls and was at least 4 times less cytotoxic than the chlorine disinfected wastewaters. These results indicate that compared to chlorination and chloramination, ozonation of wastewater with high Br-/I- levels yielded the lowest mammalian cell cytotoxicity, suggesting its potential as a more favorable method to disinfect wastewater with minimizing the biological toxicity in mind. Copyright © 2017. Published by Elsevier B.V.

  13. Dipole Alignment at the Carbon Nanotube and Methyl Ammonium Lead Iodide Perovskite Interface

    Energy Technology Data Exchange (ETDEWEB)

    Przepioski, Joshua [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-28

    This work correlates resonant peaks from first principles calculation on ammonia (NH3) Nitrogen 1s x-ray absorption spectroscopy (XAS) within the methyl ammonium lead iodide perovskite (CH3NH3PbI3), and proposes a curve to determine the alignment of the methyl ammonium dipole if there exists angular dependence. The Nitrogen 1s XAS was performed at varying incident angles on the perovskite with and without a carbon nanotube (CNT) interface produced from an ultrasonic spray deposition. We investigated the peak contribution from PbI2 and the poly(9,9-dioctylfluorene- 2,7-diyl) with bipyridine (PFO-BPy) wrapped around the CNT, and used normalization techniques to better identify the dipole alignment. There was angular dependence on samples containing the CNT interface suggesting an existing dipole alignment, but there was no angular dependence on the perovskite samples alone; however, more normalization techniques and experimental work must be performed in order to ensure its validity and to better describe its alignment, and possible controlling factors.

  14. Growth and characterization of bis thiourea cadmium iodide: A semiorganic single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Caroline, M. Lydia [Department of Physics, Bharath University, Selaiyur, Chennai 600073 (India)], E-mail: lydiacaroline2006@yahoo.co.in; Vasudevan, S. [Department of Physics, Easwari Engineering College, Ramapuram, Chennai 600089 (India)], E-mail: profsvasu@hotmail.com

    2009-02-15

    Single crystals of bis thiourea cadmium iodide[CdI{sub 2}(CH{sub 4}N{sub 2}S){sub 2}], abbreviated as BTCI, a semiorganic material has been successfully grown by both slow evaporation and slow cooling methods. Crystal of dimensions up to 3.3 x 1.0 x 1.5 cm{sup 3} is reported. Single crystal X-ray diffraction analysis has been carried out to confirm monoclinic system and etching studies for their perfection. The morphology of the grown crystal was also identified by single crystal X-ray diffraction analysis. The powder X-ray diffractogram of the crystal has been recorded and the various planes of reflection are identified. The presence of functional groups and the coordination of metal ions to thiourea were confirmed by FTIR analysis. Transmission spectra reveals that the crystal has low UV cutoff of 324 nm and has a good transmittance in the entire visible region enabling its use in optical applications. The thermal behaviour of the crystal has been investigated using thermogravimetric analysis (TGA) and differential thermal analysis (DTA), which indicates that the material does not decompose before melting. Studies of dielectric properties (dielectric constant and dielectric loss) both as function of frequencies (100 Hz to 5 MHz) for varying temperatures in the range 308-348 K suggests good candidate for electro optic modulators.

  15. Acid-catalysed chlorine transfer from N-chloramines to iodide ion: experimental evidence for a predicted change in mechanism.

    Science.gov (United States)

    Calvo, Paula; Crugeiras, Juan; Ríos, Ana

    2010-09-21

    Rate constants for acid catalysis of the reactions of N-chlorodimethylamine (1), N-chloro-2,2,2-trifluoroethylamine (2) and N,N-dichlorotaurine (3) with iodide ion were determined in H(2)O at 25 degrees C and I = 0.5 (NaClO(4)). The failure to detect significant catalysis by general acids of chlorine transfer from 1 to the nucleophile, together with the observed inverse solvent deuterium isotope effect on the hydronium ion-catalysed reaction (k(H)/k(D) = 0.37), indicates that this process occurs by protonation of 1 in a fast equilibrium step, followed by rate determining chlorine transfer to iodide ion. The appearance of general acid catalysis for the reactions of 2 and 3 shows that increasing the leaving group ability leads to a change to a concerted mechanism, which is suggested to be enforced by the absence of a significant lifetime of the protonated chloramine intermediate in the presence of iodide ion.

  16. EPR investigation of zinc/iodine exchange between propargyl iodides and diethylzinc: detection of propargyl radical by spin trapping.

    Science.gov (United States)

    Maury, Julien; Jammi, Suribabu; Vibert, François; Marque, Sylvain R A; Siri, Didier; Feray, Laurence; Bertrand, Michèle

    2012-10-19

    The production of propargyl radicals in the reaction of dialkylzincs with propargyl iodides in nondegassed medium was investigated by EPR using tri-tert-butylnitrosobenzene (TTBNB) as a spin trap. The radical mechanism and the nature of the observed species were confirmed by the trapping of propargyl radicals generated by an alternative pathway: i.e., upon irradiation of propargyl iodides in the presence of hexa-n-butyldistannane. In dialkylzinc-mediated experiments a high concentration of adduct was instantaneously observed, whereas no spontaneous production of spin adduct was detected in a blank experiment performed with the propargylic iodide and TTBNB in the absence of diethylzinc. Under irradiation in the presence of distannane, two different species were observed at the very beginning of the irradiation; the nitroxide resulting from the trapping of propargyl radical at the propargyl carbon remained the only species detected after irradiating for several minutes. The absence of adducts resulting from the trapping of allenyl canonical forms was supported by DFT calculations and by the preparation of an authentic sample.

  17. On the Mechanism of the Iodide-Triiodide Exchange Reaction in a Solid-State Ionic Liquid.

    Science.gov (United States)

    Grossi, Joás; Kohanoff, Jorge J; English, Niall J; Bringa, Eduardo M; Del Pópolo, Mario G

    2017-07-06

    Efficient charge transport has been observed in iodide-based room-temperature ionic liquids when doped with iodine. To investigate preferred pathways for the iodide (I-)-to-triiodide (I3-) exchange reaction and to clarify the origin of this high ionic conductivity, we have conducted electronic structure calculations in the crystal state of 1-butyl-3-methylimidazolium iodide ([BMIM][I]). Energy barriers for the different stages of the iodine-swapping process, including the reorientation of the I-···I3- moiety, were determined from minimum energy paths as a function of a reaction coordinate. Hirshfeld charges and structural parameters, such as bond lengths and angles, were monitored during the reaction. Several bond-exchange events were observed with energy barriers ranging from 0.17 to 0.48 eV and coinciding with the formation of a twisted I-···I3- complex. Striking similarities were observed in the mechanics and energetics of this charge-transfer process in relation to solid-state superionic conductors.

  18. Comparison of two novel in-syringe dispersive liquid-liquid microextraction techniques for the determination of iodide in water samples using spectrophotometry.

    Science.gov (United States)

    Kaykhaii, Massoud; Sargazi, Mona

    2014-01-01

    Two new, rapid methodologies have been developed and applied successfully for the determination of trace levels of iodide in real water samples. Both techniques are based on a combination of in-syringe dispersive liquid-liquid microextraction (IS-DLLME) and micro-volume UV-Vis spectrophotometry. In the first technique, iodide is oxidized with nitrous acid to the colorless anion of ICl2(-) at high concentration of hydrochloric acid. Rhodamine B is added and by means of one step IS-DLLME, the ion-pair formed was extracted into toluene and measured spectrophotometrically. Acetone is used as dispersive solvent. The second method is based on the IS-DLLME microextraction of iodide as iodide/1, 10-phenanthroline-iron((II)) chelate cation ion-pair (colored) into nitrobenzene. Methanol was selected as dispersive solvent. Optimal conditions for iodide extraction were determined for both approaches. Methods are compared in terms of analytical parameters such as precision, accuracy, speed and limit of detection. Both methods were successfully applied to determining iodide in tap and river water samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Self-diffusion coefficients of the trivalent f-element ion series in dilute and moderately dilute aqueous solutions: A comparative study between europium, gadolinium, terbium and berkelium

    Science.gov (United States)

    Rafik, Besbes; Noureddine, Ouerfelli; Abderabbou, Abdelmanef; Habib, Latrous

    2010-03-01

    We have continued the studies on the trivalent ions of the 4f and 5f elements. In this paper, we compare the transport properties (self-diffusion coefficient) of the trivalent aquo ions over two ranges of concentrations (0 — 2×10-3M) and (2×10-3 — 1.5M). Self-diffusion coefficients, D, of the trivalent f-element aquo ion series have been determined in aqueous background electrolytes of Gd(NO3)3 and Nd(ClO4)3, at pH=2.5 (HNO3, HClO4) and at 25°C using the open-end capillary method (O.E.C.M.). This method measures the transportation time of ions across a fixed distance. In this paper, we complete a measurement of self-diffusion coefficient for terbium. We optimized the pH to avoid hydrolysis, ion-pairing and complexation of the trivalent 4f and 5f ions. The variation of D versus √C is not linear for dilute solutions (0 — 2×10-3M) and quasi-linear in moderate concentrations (C<=1.5 M). Similar behavior was observed for Tb, as compared with those for Bk, Eu and Gd. We complete the comparison variation of D/D° versus √C for all studied 4f and 5f elements from concentration 0 to 1.5M and we obtained the same variation with √C for all studied elements. All 4f and 5f elements studied follow the Nernst-Hartley expression.

  20. Terbium-based time-gated Förster resonance energy transfer imaging for evaluating protein-protein interactions on cell membranes.

    Science.gov (United States)

    Lindén, Stina; Singh, Manish Kumar; Wegner, K David; Regairaz, Marie; Dautry, François; Treussart, François; Hildebrandt, Niko

    2015-03-21

    Fluorescence imaging of cells and subcellular compartments is an essential tool to investigate biological processes and to evaluate the development and progression of diseases. In particular, protein-protein interactions can be monitored by Förster resonance energy transfer (FRET) between two proximal fluorophores that are attached to specific recognition biomolecules such as antibodies. We investigated the membrane expression of E- and N-cadherins in three different cell lines used as model systems to study epithelial to mesenchymal transition (EMT) and a possible detection of circulating tumour cells (CTCs). EMT is a key process in cancer metastasis, during which epithelial markers (such as E-cadherin) are down-regulated in the primary tumour whereas mesenchymal markers (such as N-cadherin) are up-regulated, leading to enhanced cell motility, intravasation, and appearance of CTCs. Various FRET donor-acceptor pairs and protein recognition strategies were utilized, in which Lumi4-Tb terbium complexes (Tb) and different organic dyes were conjugated to several distinct E- and N-cadherin-specific antibodies. Pulsed excitation of Tb at low repetition rates (100 Hz) and time-gated (TG) imaging of both the Tb-donor and the dye-acceptor photoluminescence (PL) allowed efficient detection of the EMT markers as well as FRET in the case of sufficient donor-acceptor proximity. Efficient FRET was observed only between two E-cadherin-specific antibodies and further experiments indicated that these antibodies recognized the same E-cadherin molecule, suggesting a limited accessibility of cadherins when they are clustered at adherens junctions. The investigated Tb-to-dye FRET systems provided reduced photobleaching compared to the AlexaFluor 488-568 donor-acceptor pair. Our results demonstrate the applicability and advantages of Tb-based TG FRET for efficient and stable imaging of antibody-antibody interactions on different cell lines. They also reveal the limitations of

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

    Directory of Open Access Journals (Sweden)

    Angélique eLEVOYE

    2015-11-01

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

  2. Crystal structure of an eight-coordinate terbium(III ion chelated by N,N′-bis(2-hydroxybenzyl-N,N′-bis(pyridin-2-ylmethylethylenediamine (bbpen2− and nitrate

    Directory of Open Access Journals (Sweden)

    Thaiane Gregório

    2015-01-01

    Full Text Available The reaction of terbium(III nitrate pentahydrate in acetonitrile with N,N′-bis(2-hydroxybenzyl-N,N′-bis(pyridin-2-ylmethylethylenediamine (H2bbpen, previously deprotonated with triethylamine, produced the mononuclear compound [N,N′-bis(2-oxidobenzyl-κO-N,N′-bis(pyridin-2-ylmethyl-κNethylenediamine-κ2N,N′](nitrato-κ2O,O′terbium(III, [Tb(C28H28N4O2(NO3]. The molecule lies on a twofold rotation axis and the TbIII ion is eight-coordinate with a slightly distorted dodecahedral coordination geometry. In the symmetry-unique part of the molecule, the pyridine and benzene rings are both essentially planar and form a dihedral angle of 61.42 (7°. In the molecular structure, the N4O4 coordination environment is defined by the hexadentate bbpen ligand and the bidentate nitrate anion. In the crystal, a weak C—H...O hydrogen bond links molecules into a two-dimensional network parallel to (001.

  3. Expression of thyrotropin receptor, thyroglobulin, sodium-iodide symporter, and thyroperoxidase by fibrocytes depends on AIRE.

    Science.gov (United States)

    Fernando, Roshini; Lu, Ying; Atkins, Stephen J; Mester, Tunde; Branham, Kari; Smith, Terry J

    2014-07-01

    CD34(+) fibrocytes, bone marrow-derived progenitor cells, infiltrate orbital connective tissue in thyroid-associated ophthalmopathy, a manifestation of Graves' disease. In the orbit, they become CD34(+) fibroblasts and coexist with native CD34(-) fibroblasts. Fibrocytes have been shown to express TSH receptor and thyroglobulin. The objective of the study was to determine whether a broader repertoire of thyroid protein expression can be detected in fibrocytes and whether a common factor is responsible. Fibrocytes and fibroblasts were collected and analyzed from healthy individuals and those with Graves' disease in an academic clinical practice. Real-time PCR, Western blot analysis, gene promoter analysis, cell transfections, and flow cytometric cell sorting were performed. We detect two additional thyroid proteins expressed by fibrocytes, namely sodium-iodide symporter and thyroperoxidase. The autoimmune regulator (AIRE) protein appears necessary for this expression. AIRE expression in fibrocytes results from an active AIRE gene promoter and stable AIRE mRNA. Knocking down AIRE with a targeting small interfering RNA reduces the expression of these thyroid proteins in fibrocytes as well as the transcription factors paired box-8 and thyroid transcription factor-1. When compared with an unaffected first-degree relative, levels of these proteins are substantially reduced in fibrocytes from an individual with an inactivating AIRE mutation. Levels of AIRE and the thyroid proteins are lower in orbital fibroblasts from patients with thyroid-associated ophthalmopathy than in fibrocytes. However, when mixed fibroblast populations are sorted into pure CD34(+) and CD34(-) subsets, the levels of these proteins are dramatically increased selectively in CD34(+) fibroblasts. Fibrocytes express four proteins, the aggregate expression of which was previously thought to be restricted to thyroid epithelium. These proteins represent the necessary molecular biosynthetic machinery

  4. Biocompatibility and bond degradation of poly-acrylic acid coated copper iodide-adhesives.

    Science.gov (United States)

    ALGhanem, Adi; Fernandes, Gabriela; Visser, Michelle; Dziak, Rosemary; Renné, Walter G; Sabatini, Camila

    2017-09-01

    To investigate the effect of poly-acrylic acid (PAA) copper iodide (CuI) adhesives on bond degradation, tensile strength, and biocompatibility. PAA-CuI particles were incorporated into Optibond XTR, Optibond Solo and XP Bond in 0.1 and 0.5mg/ml. Clearfil SE Protect, an MDPB-containing adhesive, was used as control. The adhesives were applied to human dentin, polymerized and restored with composite in 2mm-increments. Resin-dentin beams (0.9±0.1mm2) were evaluated for micro-tensile bond strength after 24h, 6 months and 1year. Hourglass specimens (10×2×1mm) were evaluated for ultimate tensile strength (UTS). Cell metabolic function of human gingival fibroblast cells exposed to adhesive discs (8×1mm) was assessed with MTT assay. Copper release from adhesive discs (5×1mm) was evaluated with UV-vis spectrophotometer after immersion in 0.9% NaCl for 1, 3, 5, 7, 10, 14, 21 and 30 days. SEM, EDX and XRF were conducted for microstructure characterization. XTR and Solo did not show degradation when modified with PAA-CuI regardless of the concentration. The UTS for adhesives containing PAA-CuI remained unaltered relative to the controls. The percent viable cells were reduced for Solo 0.5mg/ml and XP 0.1 or 0.5mg/ml PAA-CuI. XP demonstrated the highest ion release. For all groups, the highest release was observed at days 1 and 14. PAA-CuI particles prevented the bond degradation of XTR and Solo after 1year without an effect on the UTS for any adhesive. Cell viability was affected for some adhesives. A similar pattern of copper release was demonstrated for all adhesives. Copyright © 2017. Published by Elsevier Ltd.

  5. Nitrosyl Iodide, Ino: Millimeter-Wave Spectroscopy Guided by AB Initio Quantum Chemical Computation

    Science.gov (United States)

    Bailleux, Stephane; Duflot, Denis; Aiba, Shohei; Ozeki, Hiroyuki

    2015-06-01

    In the series of the nitrosyl halides, XNO (where X = {F, Cl, Br, I}), the millimeter-wave spectrum of INO remains so far unknown. We report our investigation on the first high-resolution rotational spectroscopy of nitrosyl iodide, INO. One of the motivation for this work comes from the growing need in developing a more complete understanding of atmospheric chemistry, especially halogen and nitrogen oxides chemistry that adversely impacts ozone levels. In the family of the nitrogen oxyhalides such as nitrosyl (XNO), nitryl (XNO), nitrite (XONO), and nitrate (XON0_2) halides, those with X = {F, Cl, Br} have been well studied, both theoretically and experimentally. However, relatively little is known about the iodine-containing analogues, although they also are of potential importance in tropospheric chemistry. In 1991, the Fourier-transform IR spectroscopic detection of INO, INO_2 and IONO_2 in the gas phase has been reported The INO molecule was generated by in situ mixing continuously I_2 and NO in a 50-cm long reaction glass tube whose outlet was connected to the absorption cell using a teflon tube. At the time of writing this abstract, 68 μ_a-type transitions (K_a = 0-10), all weak, have been successfully assigned. The hyperfine structures due to both I and N nuclei will also be presented. S.B. and D.D. acknowledge support from the Laboratoire d'Excellence CaPPA (Chemical and Physical Properties of the Atmosphere) through contract ANR-10-LABX-005 of the Programme d'Investissement d'Avenir. I. Barnes, K. H. Becker and J. Starcke, J. Phys. Chem. 1991, 95, 9736-9740.

  6. Parametric studies of radiolytic oxidation of iodide solutions with and without paint: comparison with code calculations

    Energy Technology Data Exchange (ETDEWEB)

    Poletiko, C.; Hueber, C. [Inst. de Protection et de Surete Nucleaire, C.E. Cadarache, St. Paul-lez-Durance (France); Fabre, B. [CISI, C.E. Cadarache, St. Paul-lez-Durance (France)

    1996-12-01

    In case of severe nuclear accident, radioactive material may be released into the environment. Among the fission products involved, are the very volatile iodine isotopes. However, the chemical forms are not well known due to the presence of different species in the containment with which iodine may rapidly react to form aerosols, molecular iodine, hydroiodic acid and iodo-organics. Tentative explanations of different mechanisms were performed through benchscale tests. A series of tests has been performed at AEA Harwell (GB) to study parameters such as pH, dose rate, concentration, gas flow rate, temperature in relation to molecular iodine production, under dynamic conditions. Another set of tests has been performed in AECL Whiteshell (CA) to study the behaviour of painted coupons, standing in gas phase or liquid phase or both, with iodine compounds under radiation. The purpose of our paper is to synthesize the data and compare the results to the IODE code calculation. Some parameters of the code were studied to fit the experimental result the best. A law, concerning the reverse reaction of iodide radiolytic oxidation, has been proposed versus: pH, concentrations and gas flow-rate. This law does not apply for dose rate variations. For the study of painted coupons, it has been pointed out that molecular iodine tends to be adsorbed or chemically absorbed on the surface in gas phase, but the mechanism should be more sophisticated in the aqueous phase. The iodo-organics present in liquid phase tend to be partly or totally destroyed by oxidation under radiation (depending upon the dose delivered). These points are discussed. (author) 18 figs., 3 tabs., 15 refs.

  7. Iodide and iodate effects on the growth and fruit quality of strawberry.

    Science.gov (United States)

    Li, Rui; Liu, Hui-Ping; Hong, Chun-Lai; Dai, Zi-Xi; Liu, Jia-Wei; Zhou, Jun; Hu, Chun-Qing; Weng, Huan-Xin

    2017-01-01

    Iodine deficiency is an environmental health problem affecting one-third of the global population. An iodine biofortification hydroponic experiment was conducted to explore the iodide and iodate uptake characteristics of strawberry plants, to measure the dosage effects of iodine on plant growth and to evaluate the influence of I - or IO 3 - application on fruit quality. After biofortification, the iodine contents of the fresh strawberry fruits were 600-4000 µg kg -1 , covering the WHO dietary iodine allowance of 150 µg · day -1 for adults. The iodine uptake of the strawberry plants increased with increasing I - or IO 3 - concentration of the culture solution. At the same iodine concentration, the iodate uptakes of various plant organs under I - treatments were apparently more than those under IO 3 - treatments. Low-level exogenous iodine (I - ≤ 0.25 mg L -1 or IO 3 - ≤ 0.50 mg L -1 ) not only promoted plant growth and increased biomass per plant, but also improved fruit quality by enhancing the vitamin C and soluble sugar contents of the strawberry fruits. Nevertheless, excessive exogenous iodine inhibited plant growth and reduced biomass per plant. IO 3 - uptake apparently increased the total acidity and nitrate content of the fruits, reducing the quality of the strawberry fruits. Conversely, I - uptake obviously decreased the total acidity and nitrate content of the strawberry fruits, improving the fruit quality. The strawberry can be used as a target crop for iodine biofortification. Furthermore, applying an appropriate dose of KI can improve the fruit quality of the strawberry plants. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  8. Investigations regarding the wet decontamination of fluorescent lamp waste using iodine in potassium iodide solutions.

    Science.gov (United States)

    Tunsu, Cristian; Ekberg, Christian; Foreman, Mark; Retegan, Teodora

    2015-02-01

    With the rising popularity of fluorescent lighting, simple and efficient methods for the decontamination of discarded lamps are needed. Due to their mercury content end-of-life fluorescent lamps are classified as hazardous waste, requiring special treatment for disposal. A simple wet-based decontamination process is required, especially for streams where thermal desorption, a commonly used but energy demanding method, cannot be applied. In this study the potential of a wet-based process using iodine in potassium iodide solution was studied for the recovery of mercury from fluorescent lamp waste. The influence of the leaching agent's concentration and solid/liquid ratio on the decontamination efficiency was investigated. The leaching behaviour of mercury was studied over time, as well as its recovery from the obtained leachates by means of anion exchange, reduction, and solvent extraction. Dissolution of more than 90% of the contained mercury was achieved using 0.025/0.05 M I2/KI solution at 21 °C for two hours. The efficiency of the process increased with an increase in leachant concentration. 97.3 ± 0.6% of the mercury contained was dissolved at 21 °C, in two hours, using a 0.25/0.5M I2/KI solution and a solid to liquid ratio of 10% w/v. Iodine and mercury can be efficiently removed from the leachates using Dowex 1X8 anion exchange resin or reducing agents such as sodium hydrosulphite, allowing the disposal of the obtained solution as non-hazardous industrial wastewater. The extractant CyMe4BTBP showed good removal of mercury, with an extraction efficiency of 97.5 ± 0.7% being achieved in a single stage. Better removal of mercury was achieved in a single stage using the extractants Cyanex 302 and Cyanex 923 in kerosene, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Dimethyl phenyl piperazine iodide (DMPP) induces glioma regression by inhibiting angiogenesis

    Energy Technology Data Exchange (ETDEWEB)

    He, Yan-qing; Li, Yan; Wang, Xiao-yu [Key Laboratory for Regenerative Medicine of the Ministry of Education, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632 (China); He, Xiao-dong [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510006 (China); Jun, Li [Guangdong Provincial Key Laboratory of Bioengineering Medicine, National Engineering Research Centre of Genetic Medicine, College of Life Science and Technology, Jinan University, Guangzhou 510632 (China); Chuai, Manli [Division of Cell and Developmental Biology, University of Dundee, Dundee, DD1 5EH (United Kingdom); Lee, Kenneth Ka Ho [Key Laboratory for Regenerative Medicine of the Ministry of Education, School of Biomedical Sciences, Chinese University of Hong Kong, Shatin (Hong Kong); Wang, Ju [Guangdong Provincial Key Laboratory of Bioengineering Medicine, National Engineering Research Centre of Genetic Medicine, College of Life Science and Technology, Jinan University, Guangzhou 510632 (China); Wang, Li-jing, E-mail: wanglijing62@163.com [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510006 (China); Yang, Xuesong, E-mail: yang_xuesong@126.com [Key Laboratory for Regenerative Medicine of the Ministry of Education, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632 (China)

    2014-01-15

    1,1-Dimethyl-4-phenyl piperazine iodide (DMPP) is a synthetic nicotinic acetylcholine receptor (nAChR) agonist that could reduce airway inflammation. In this study, we demonstrated that DMPP could dramatically inhibit glioma size maintained on the chick embryonic chorioallantoic membrane (CAM). We first performed MTT and BrdU incorporation experiments on U87 glioma cells in vitro to understand the mechanism involved. We established that DMPP did not significantly affect U87 cell proliferation and survival. We speculated that DMPP directly caused the tumor to regress by affecting the vasculature in and around the implanted tumor on our chick CAM model. Hence, we conducted detailed analysis of DMPP's inhibitory effects on angiogenesis. Three vasculogenesis and angiogenesis in vivo models were used in the study which included (1) early chick blood islands formation, (2) chick yolk-sac membrane (YSW) and (3) CAM models. The results revealed that DMPP directly suppressed all developmental stages involved in vasculogenesis and angiogenesis – possibly by acting through Ang-1 and HIF-2α signaling. In sum, our results show that DMPP could induce glioma regression grown on CAM by inhibiting vasculogenesis and angiogenesis. - Highlights: ●We demonstrated that DMPP inhibited the growth of glioma cells on chick CAM. ●DMPP did not significantly affect the proliferation and survival of U87 cells. ●We revealed that DMPP suppressed vasculogenesis and angiogenesis in chick embryo. ●Angiogenesis in chick CAM was inhibited by DMPP via most probably Ang-1 and HIF-2α. ●DMPP could be potentially developed as an anti-tumor drug in the future.

  10. Bimetallic AgCu/Cu2O hybrid for the synergetic adsorption of iodide from solution.

    Science.gov (United States)

    Mao, Ping; Liu, Ying; Liu, Xiaodong; Wang, Yuechan; Liang, Jie; Zhou, Qihang; Dai, Yuexuan; Jiao, Yan; Chen, Shouwen; Yang, Yi

    2017-08-01

    To further improve the capacity of Cu 2 O to absorb I - anions from solution, and to understand the difference between the adsorption mechanisms of Ag/Cu 2 O and Cu/Cu 2 O adsorbents, bimetallic AgCu was doped into Cu 2 O through a facile solvothermal route. Samples were characterized and employed to adsorb I - anions under different experimental conditions. The results show that the Cu content can be tuned by adding different volumes of Ag sols. After doping bimetallic AgCu, the adsorption capacity of the samples can be increased from 0.02 mmol g -1 to 0.52 mmol g -1 . Moreover, the optimal adsorption is reached within only 240 min. Meanwhile, the difference between the adsorption mechanisms of Ag/Cu 2 O and Cu/Cu 2 O adsorbents was verified, and the cooperative adsorption mechanism of the AgCu/Cu 2 O hybrid was proposed and verified. In addition, the AgCu/Cu 2 O hybrid showed excellent selectivity, e.g., its adsorption efficiencies are 85.1%, 81.9%, 85.9% and 85.7% in the presence of the Cl - , CO 3 2- , SO 4 2- and NO 3 - competitive anions, respectively. Furthermore, the AgCu/Cu 2 O hybrid can worked well in other harsh environments (e.g., acidic, alkaline and seawater environments). Therefore, this study is expected to promote the development of Cu 2 O into a highly efficient adsorbent for the removal of iodide from solution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Mercury separation from concentrated potassium iodide/iodine leachate using Self-Assembled Mesoporous Mercaptan Support (SAMMS) technology

    Energy Technology Data Exchange (ETDEWEB)

    Mattigod, S.V.; Feng, X.; Fryxell, G.E. [and others

    1997-10-01

    A study was conducted to demonstrate the effectiveness of a novel adsorber, the Self-Assembled Mesoporous Mercaptan Support (SAMMS) material to remove mercury (Hg) from potassium iodide/iodine (KI/I{sub 2}) waste streams. This study included investigations of the SAMMS material`s binding kinetics, loading capacity, and selectivity for Hg adsorption from surrogate and actual KI/I{sub 2} waste solutions. The kinetics data showed that binding of Hg by the adsorber material occurs very rapidly, with 82% to 95% adsorption occurring within the first 5 min. No significant differences in the rate of adsorption were noted between pH values of 5 and 9 and at Hg concentrations of {approximately}100 mg/1. Within the same range of pH values, an approximate four-fold increase in initial Hg concentration resulted in a two-fold increase in the rate of adsorption. In all cases studied, equilibrium adsorption occured within 4 h. The loading capacity experiments in KI/I{sub 2} surrogate solutions indicated Hg adsorption densities between 26 to 270 mg/g. The loading density increased with increasing solid: solution ratio and decreasing iodide concentrations. Values of distribution coefficients (1.3x10{sup 5} to >2.6x10{sup 8} ml/g) indicated that material adsorbs Hg with very high specificity from KI/I{sub 2} surrogate solutions. Reduction studies showed that compared to metallic iron (Fe), sodium dithionite can very rapidly reduce iodine as the triiodide species into the iodide form. Adsorption studies conducted with actual KI/I{sub 2} leachates confirmed the highly specific Hg adsorption properties (K{sub d}>6x10{sup 7} to>1x10{sup 8} ml//g) of the adsorber material. Following treatment, the Hg concentrations in actual leachates were below instrumental detection limits (i.e., < 0.00005 mg/l), indicating that the KI solutions can be recycled.

  12. Potassium iodide (KI) to block the thyroid from exposure to I-131: current questions and answers to be discussed

    Energy Technology Data Exchange (ETDEWEB)

    Reiners, Christoph; Schneider, Rita [Hospital of the University of Wuerzburg, Department of Nuclear Medicine, German WHO-REMPAN Collaboration Center, Wuerzburg (Germany)

    2013-05-15

    Thyroid cancer in children and adolescents has to be considered as the most severe health consequence of a nuclear reactor emergency with release of radioiodine into the atmosphere. High doses of potassium iodide are effective to block radioiodine thyroid uptake and to prevent development of thyroid cancer years later. However, there are controversies concerning thyroid cancer risk induced by radioiodine exposure in adults. Further, the interaction of nutritional supply of potassium iodide and radioiodine uptake as well as the interaction of radioiodine with certain drugs has not been addressed properly in existing guidelines and recommendations. How to proceed in case of repeated release of radioiodine is an open, very important question which came up again recently during the Fukushima accident. Lastly, the side effects of iodine thyroid blocking and alternatives of this procedure have not been addressed systematically up to now in guidelines and recommendations. These questions can be answered as follows: in adults, the risk to develop thyroid cancer is negligible. In countries, where nutritional iodine deficiency is still an issue, the risk to develop thyroid cancer after a nuclear reactor emergency has to be considered higher because the thyroid takes up more radioiodine as in the replete condition. Similarly, in patients suffering from thyrotoxicosis, hypothyroidism or endemic goitre not being adequately treated radioiodine uptake is higher than in healthy people. In case of repeated or continued radioiodine release, more than one dose of potassium iodide may be necessary and be taken up to 1 week. Repeated iodine thyroid blocking obviously is not harmful. Side effects of iodine thyroid blocking should not be overestimated; there is little evidence for adverse effects in adults. Newborns and babies, however, may be more sensitive to side effects. In the rare case of iodine hypersensitivity, potassium perchlorate may be applied as an alternative to iodine for

  13. Iodide Selective Electrodes Based on Bis(2-mercaptobenzothiazolato Mercury(II and Bis(4-chlorothiophenolato Mercury(II Carriers

    Directory of Open Access Journals (Sweden)

    Morteza M. Zohory

    2003-12-01

    Full Text Available New iodide-selective electrodes based on bis(2-mercaptobenzothiazolato mercury(II [Hg(MBT2] and bis(4-chlorothiophenolato mercury(II [Hg(CTP2] carriers are described. The electrodes were prepared by incorporating the ionophores into plasticized PVC membranes, which were directly coated on the surface of graphite disk electrodes. The electrodes displayed high selectivity for iodide with respect to a number of inorganic and organic anions. The influence of the membrane composition and pH, and the effect of lipophilic cationic and anionic additives on the response properties of the electrodes were investigated. The electrodes exhibited near-Nernstian slopes of -57.6 ± 0.8 and -58.4 ± 1.4 mV/decade of iodide concentration over the range 1 × 10-6 – 1 × 10-1 M, with detection limits of ~4 × 10-7 and 6 × 10-7 M for the electrodes based on [Hg(MBT2] and [Hg(CTP2], respectively. They have relatively fast response times (≤ 10 s, satisfactory reproducibility, and life times of at least two months. The potentiometric responses of the electrodes are independent of pH of the test solution over the range 3.5 – 11.5.

  14. Two dimensional simulation of hydrogen iodide decomposition reaction using fluent code for hydrogen production using nuclear technology

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Jung Sik [The Institute of Machinery and Electronic Technology, Mokpo National Maritime University, Mokpo (Korea, Republic of); Shin, Young Joon; Lee, Ki Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Choi, Jae Hyuk [Division of Marine Engineering System, Korea Maritime and Ocean University, Busan (Korea, Republic of)

    2015-06-15

    The operating characteristics of hydrogen iodide (HI) decomposition for hydrogen production were investigated using the commercial computational fluid dynamics code, and various factors, such as hydrogen production, heat of reaction, and temperature distribution, were studied to compare device performance with that expected for device development. Hydrogen production increased with an increase of the surface-to-volume (STV) ratio. With an increase of hydrogen production, the reaction heat increased. The internal pressure and velocity of the HI decomposer were estimated through pressure drop and reducing velocity from the preheating zone. The mass of H2O was independent of the STV ratio, whereas that of HI decreased with increasing STV ratio.

  15. An IMPLICATION logic gate based on citrate-capped gold nanoparticles with thiocyanate and iodide as inputs.

    Science.gov (United States)

    Deng, Hao-Hua; Li, Guang-Wen; Lin, Xin-Hua; Liu, Ai-Lin; Chen, Wei; Xia, Xing-Hua

    2013-11-07

    Herein we developed an IMPLICATION logic gate based on citrate-capped AuNPs by employing thiocyanate (SCN(-)) and iodide (I(-)) as inputs, and devised a colorimetric sensor for the determination of I(-) with good selectivity and sensitivity. To the best of our knowledge, this is the first example in which two species of anions serve as inputs to obtain visually observed Boolean outputs. Under the optimum conditions, 0.8 μM I(-) could induce a significant color change and be recognized by the naked eye. The detection limit is 50 nM by using UV-vis spectroscopy.

  16. Three-dimensional imaging of carbonyl sulfide and ethyl iodide photodissociation using the pixel imaging mass spectrometry camera.

    Science.gov (United States)

    Amini, K; Blake, S; Brouard, M; Burt, M B; Halford, E; Lauer, A; Slater, C S; Lee, J W L; Vallance, C

    2015-10-01

    The Pixel Imaging Mass Spectrometry (PImMS) camera is used in proof-of-principle three-dimensional imaging experiments on the photodissociation of carbonyl sulfide and ethyl iodide at wavelengths around 230 nm and 245 nm, respectively. Coupling the PImMS camera with DC-sliced velocity-map imaging allows the complete three-dimensional Newton sphere of photofragment ions to be recorded on each laser pump-probe cycle with a timing precision of 12.5 ns, yielding velocity resolutions along the time-of-flight axis of around 6%-9% in the applications presented.

  17. The effects of barium sufate and iodide compound on the characteristics of dental acrylic resins

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Keun; Lee, Keon Il; Jung, Sung Woo [Dept. of Oral Radiology, College of Dentistry, Wonkwang University, Iksan(Korea, Republic of)

    1996-08-15

    Aspiratin or swallowing foreign bodies is a common occurrence. If they are wholly or partly radiopaque, their localization in and progress through the gastrointestinal tract can be more effective. Of the dental origin foreign materials swallowed, the most common things are fragments of anterior maxillary partial denture. But the radiopacity of denture base resins is not sufficient to determine the location of the objects. The purpose of this study was to develop a radiopaque dental acrylic resin, which has clinically detectable radiopacity with minimal change of mechanical properties and color. the radiopacity, color change (CIE E) and microhardness of acrylic resins were determined after mixing barium sulfate or iolide compound. Thermocycling course was conducted to deter mine the change of characteristic of resins after using for a long time I the mouth. Five or ten percent of barium sulfa te to total weight of cured material was mixed with heat curing dental acrylic resin or chemically curing orthodontic re sin. In the case of iodide compound, the mixing ratio was two or three percent. After mixing the high radiopaque material s, resin was cured to 20X20X2 mm plate, polished with 600 sand paper and finally polished with Microcloth (Buehler). T he specimens were thermocycled in 5 and 55 degree distilled water for 2,000 times, and the measurement of radiopacity, color and Vickers hardness was repeated every 500 times thermocycling. The radiopacity of specimens on the X-ray films was measured with densitometer (X-rite). The color change was determined with differential colorimeter (Model TC-6FX, Tokyo Denshoku), and the Vickers hardness number was measured with microhardness tester (Mitsuzawa). The following results were obtained : 1. All the three variables, the kinds of acrylic resins, the mixing or the kinds radiopaque materials and thermocycling , had combined effect on the radiopacity of the dental acrylic resins (p<0.01). 2. The two variables, the mixing or

  18. Potassium iodide for thyroid blockade in a reactor accident: administrative policies that govern its use.

    Science.gov (United States)

    Becker, D V; Zanzonico, P

    1997-04-01

    A marked increase in thyroid cancer among young children who were in the vicinity of the Chernobyl nuclear power plant at the time of the 1986 accident strongly suggests a possible causal relationship to the large amounts of radioactive iodine isotopes in the resulting fallout. Although remaining indoors, restricting consumption of locally produced milk and foodstuffs, and evacuation are important strategies in a major breach-of-containment accident, stable potassium iodide (KI) prophylaxis given shortly before or immediately after exposure can reduce greatly the thyroidal accumulation of radioiodines and the resulting radiation dose. Concerns about possible side effects of large-scale, medically unsupervised KI consumption largely have been allayed in light of the favorable experience in Poland following the Chernobyl accident; 16 million persons received single administrations of KI with only rare occurrence of side effects and with a probable 40% reduction in projected thyroid radiation dose. Despite the universal acceptance of KI as an effective thyroid protective agent, supplies of KI in the US are not available for public distribution in the event of a reactor accident largely because government agencies have argued that stockpiling and distribution of KI to other than emergency workers cannot be recommended in light of difficult distribution logistics, problematic administrative issue, and a calculated low cost-effectiveness. However, KI in tablet form is expensive and has a long shelf life, and many countries have largely stockpiles and distribution programs. The World Health Organization recognizes the benefits of stable KI and urges its general availability. At present there are 110 operating nuclear power plants in the US and more than 300 in the rest of the world. These reactors product 17% of the world's electricity and in some countries up to 60-70% of the total electrical energy. Almost all US nuclear power plants have multistage containment

  19. Lead iodide perovskite sensitized all-solid-state submicron thin film mesoscopic solar cell with efficiency exceeding 9%.

    KAUST Repository

    Kim, Hui-Seon

    2012-08-21

    We report on solid-state mesoscopic heterojunction solar cells employing nanoparticles (NPs) of methyl ammonium lead iodide (CH(3)NH(3))PbI(3) as light harvesters. The perovskite NPs were produced by reaction of methylammonium iodide with PbI(2) and deposited onto a submicron-thick mesoscopic TiO(2) film, whose pores were infiltrated with the hole-conductor spiro-MeOTAD. Illumination with standard AM-1.5 sunlight generated large photocurrents (J(SC)) exceeding 17 mA/cm(2), an open circuit photovoltage (V(OC)) of 0.888 V and a fill factor (FF) of 0.62 yielding a power conversion efficiency (PCE) of 9.7%, the highest reported to date for such cells. Femto second laser studies combined with photo-induced absorption measurements showed charge separation to proceed via hole injection from the excited (CH(3)NH(3))PbI(3) NPs into the spiro-MeOTAD followed by electron transfer to the mesoscopic TiO(2) film. The use of a solid hole conductor dramatically improved the device stability compared to (CH(3)NH(3))PbI(3) -sensitized liquid junction cells.

  20. Parameters influencing the deposition of methylammonium lead halide iodide in hole conductor free perovskite-based solar cells

    Directory of Open Access Journals (Sweden)

    Bat-El Cohen

    2014-08-01

    Full Text Available Perovskite is a promising light harvester for use in photovoltaic solar cells. In recent years, the power conversion efficiency of perovskite solar cells has been dramatically increased, making them a competitive source of renewable energy. An important parameter when designing high efficiency perovskite-based solar cells is the perovskite deposition, which must be performed to create complete coverage and optimal film thickness. This paper describes an in-depth study on two-step deposition, separating the perovskite deposition into two precursors. The effects of spin velocity, annealing temperature, dipping time, and methylammonium iodide concentration on the photovoltaic performance are studied. Observations include that current density is affected by changing the spin velocity, while the fill factor changes mainly due to the dipping time and methylammonium iodide concentration. Interestingly, the open circuit voltage is almost unaffected by these parameters. Hole conductor free perovskite solar cells are used in this work, in order to minimize other possible effects. This study provides better understanding and control over the perovskite deposition through highly efficient, low-cost perovskite-based solar cells.

  1. P(MMA-EMA Random Copolymer Electrolytes Incorporating Sodium Iodide for Potential Application in a Dye-Sensitized Solar Cell

    Directory of Open Access Journals (Sweden)

    Nurul Akmaliah Dzulkurnain

    2015-02-01

    Full Text Available Polymer electrolytes based on 90 wt% of methyl methacrylate and 10 wt% of ethyl methacrylate (90MMA-co-10EMA incorporating different weight ratios of sodium iodide were prepared using the solution casting method. The complexation between salt and copolymer host has been investigated using Fourier transform infrared spectroscopy. The ionic conductivity and thermal stability of the electrolytes were measured using impedance spectroscopy and differential scanning calorimetry, respectively. Scanning electron microscopy was used to study the morphology of the polymer electrolytes. The ionic conductivity and glass transition temperature increased up to 20 wt% of sodium iodide (5.19 × 10−6 S·cm−1 and decreased with the further addition of salt concentration, because of the crosslinked effect. The morphology behavior of the highest conducting sample also showed smaller pores compared to the other concentration. The total ionic transference number proved that this system was mainly due to ions, and the electrochemical stability window was up to 2.5 V, which is suitable for a dye-sensitized solar cell application. This sample was then tested in a dye-sensitized solar cell and exhibited an efficiency of 0.62%.

  2. Chlorine Dioxide-Iodide-Methyl Acetoacetate Oscillation Reaction Investigated by UV-Vis and Online FTIR Spectrophotometric Method

    Directory of Open Access Journals (Sweden)

    Laishun Shi

    2012-01-01

    Full Text Available In order to study the chemical oscillatory behavior and mechanism of a new chlorine dioxide-iodide ion-methyl acetoacetate reaction system, a series of experiments were done by using UV-Vis and online FTIR spectrophotometric method. The initial concentrations of methyl acetoacetate, chlorine dioxide, potassium iodide, and sulfuric acid and the pH value have great influence on the oscillation observed at wavelength of 289 nm. There is a preoscillatory or induction period, and the amplitude and the number of oscillations are associated with the initial concentration of reactants. The equations for the triiodide ion reaction rate changing with reaction time and the initial concentrations in the oscillation stage were obtained. Oscillation reaction can be accelerated by increasing temperature. The apparent activation energies in terms of the induction period and the oscillation period were 26.02 KJ/mol and 17.65 KJ/mol, respectively. The intermediates were detected by the online FTIR analysis. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism was proposed for the oscillation reaction.

  3. Methylammonium Iodide Effect on the Supersaturation and Interfacial Energy of the Crystallization of Methylammonium Lead Triiodide Single Crystals.

    Science.gov (United States)

    Li, Bichen; Isikgor, Furkan; Coskun, Hikmet; Ouyang, Jianyong

    2017-10-26

    It is very important to study the crystallization of hybrid organic-inorganic perovskites because their thin films are usually prepared from solution. But the investigation on the growth of perovskite films is limited by their polycrystallinity. In this work, methylammonium lead triiodide single crystals grown from solutions with different methylammonium iodide (MAI):lead iodide (PbI2) ratios were investigated. We observed a V-shaped dependence of the crystallization onset temperature on the MAI:PbI2 ratio. This is attributed to the MAI effects on the supersaturation of precursors and the interfacial energy of the crystal growth. At low MAI:PbI2 ratio (<1.7), more MAI leads to the supersaturation of the precursors at lower temperature. At high MAI:PbI2 ratio, the crystal growing plans change from (100)-plane dominated to (001)-plane dominated. The latter have higher interfacial energy than the former, leading to higher crystallization onset temperature. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. UV-assisted photocatalytic synthesis of highly dispersed Ag nanoparticles supported on DNA decorated graphene for quantitative iodide analysis.

    Science.gov (United States)

    Kong, Fen-Ying; Li, Wei-Wei; Wang, Jing-Yi; Wang, Wei

    2015-07-15

    Herein, we report, for the first time, the synthesis of reduced graphene oxide-DNA-Ag (RGO-DNA-Ag) nanohybrids by ultraviolet (UV) irradiation of aqueous solutions of GO and Ag ions in the presence of DNA. The morphology and microstructure characterizations of the resultant nanohybrids reveal that the proposed method leads to the simultaneous reduction of GO and Ag ions together with efficient dispersion of Ag nanoparticles on the surface of RGO sheets. This simple and fast synthesis route is carried out at ambient conditions without using any additional chemical reducing agents, which has the potential to provide new avenues for the green fabrication of various RGO-based nanomaterials. Additionally, the RGO-DNA-Ag nanohybrids can be utilized as a novel sensing interfacial for direct determination of iodide by simple differential pulse voltammetry (DPV), without requiring any preceding preconcentration of the analyte. Based on the RGO-DNA-Ag nanohybrids modified electrode, a wide linear range of 1μM-1mM and a low detection limit of 0.2μM were obtained. This sensitive and direct method of analysis can be applied successfully to the determination of iodide in real samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Rapid Selective Circumneutral Degradation of Phenolic Pollutants Using Peroxymonosulfate-Iodide Metal-Free Oxidation: Role of Iodine Atoms.

    Science.gov (United States)

    Feng, Yong; Lee, Po-Heng; Wu, Deli; Shih, Kaimin

    2017-02-21

    The development of environmentally friendly, oxidation-selective advanced oxidation processes (AOPs) for water decontamination is important for resource recovery, carbon dioxide abatement, and cost savings. In this study, we developed an innovative AOP using a combination of peroxymonosulfate (PMS) and iodide ions (I(-)) for the selective removal of phenolic pollutants from aqueous solutions. The results showed that nearly 100% degradation of phenol, bisphenol A, and hydroquinone was achieved after reaction for 4 min in the presence of 65 μM PMS and 50 μM I(-). PMS-I(-) oxidation had a wide effective pH range, with the best performance achieved under circumneutral conditions. The ratio between [PMS] and [I(-)] influenced the degradation, and the optimal ratio was approximately 1.00 for the degradation of the phenols. Neither sulfate nor hydroxyl radicals were found to be the active species in PMS-I(-) oxidation. Instead, we found evidence that iodide atoms were the dominant oxidants. In addition, both Cl(-) and Br(-) also promoted the degradation of phenol in PMS solution. The results of this work may promote the application of reactive halogen species in water treatment.

  6. Potassium Iodide Potentiates Antimicrobial Photodynamic Inactivation Mediated by Rose Bengal in In Vitro and In Vivo Studies.

    Science.gov (United States)

    Wen, Xiang; Zhang, Xiaoshen; Szewczyk, Grzegorz; El-Hussein, Ahmed; Huang, Ying-Ying; Sarna, Tadeusz; Hamblin, Michael R

    2017-07-01

    Rose bengal (RB) is a halogenated xanthene dye that has been used to mediate antimicrobial photodynamic inactivation for several years. While RB is highly active against Gram-positive bacteria, it is largely inactive in killing Gram-negative bacteria. We have discovered that addition of the nontoxic salt potassium iodide (100 mM) potentiates green light (540-nm)-mediated killing by up to 6 extra logs with the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, the Gram-positive bacterium methicillin-resistant Staphylococcus aureus, and the fungal yeast Candida albicans The mechanism is proposed to be singlet oxygen addition to iodide anion to form peroxyiodide, which decomposes into radicals and, finally, forms hydrogen peroxide and molecular iodine. The effects of these different bactericidal species can be teased apart by comparing the levels of killing achieved in three different scenarios: (i) cells, RB, and KI are mixed together and then illuminated with green light; (ii) cells and RB are centrifuged, and then KI is added and the mixture is illuminated with green light; and (iii) RB and KI are illuminated with green light, and then cells are added after illumination with the light. We also showed that KI could potentiate RB photodynamic therapy in a mouse model of skin abrasions infected with bioluminescent P. aeruginosa. Copyright © 2017 American Society for Microbiology.

  7. Preliminary design and cost of a 1-megawatt solar-pumped iodide laser space-to-space transmission station

    Science.gov (United States)

    Deyoung, R. J.; Walker, G. H.; Williams, M. D.; Schuster, G. L.; Conway, E. J.

    1987-01-01

    A preliminary conceptual design of a space-based solar pumped iodide laser emitting 1 megawatt of laser power for space-to-space power transmission is described. A near parabolic solar collector focuses sunlight onto the t-C4F9I (perfluoro-t butyl iodide) lasant within a transverse flow optical cavity. Using waste heat, a thermal system was designed to supply compressor and auxiliary power. System components were designed with weight and cost estimates assigned. Although cost is very approximate, the cost comparison of individual system components leads to valuable insights for future research. In particular, it was found that laser efficiency was not a dominant cost or weight factor, the dominant factor being the laser cavity and laser transmission optics. The manufacturing cost was approx. two thirds of the total cost with transportation to orbit the remainder. The flowing nonrenewable lasant comprised 20% of the total life cycle cost of the system and thus was not a major cost factor. The station mass was 92,000 kg without lasant, requiring approx. four shuttle flights to low Earth orbit where an orbital transfer vehicle will transport it to the final altitude of 6378 km.

  8. Lead Iodide Perovskite Sensitized All-Solid-State Submicron Thin Film Mesoscopic Solar Cell with Efficiency Exceeding 9%

    Science.gov (United States)

    Kim, Hui-Seon; Lee, Chang-Ryul; Im, Jeong-Hyeok; Lee, Ki-Beom; Moehl, Thomas; Marchioro, Arianna; Moon, Soo-Jin; Humphry-Baker, Robin; Yum, Jun-Ho; Moser, Jacques E.; Grätzel, Michael; Park, Nam-Gyu

    2012-01-01

    We report on solid-state mesoscopic heterojunction solar cells employing nanoparticles (NPs) of methyl ammonium lead iodide (CH3NH3)PbI3 as light harvesters. The perovskite NPs were produced by reaction of methylammonium iodide with PbI2 and deposited onto a submicron-thick mesoscopic TiO2 film, whose pores were infiltrated with the hole-conductor spiro-MeOTAD. Illumination with standard AM-1.5 sunlight generated large photocurrents (JSC) exceeding 17 mA/cm2, an open circuit photovoltage (VOC) of 0.888 V and a fill factor (FF) of 0.62 yielding a power conversion efficiency (PCE) of 9.7%, the highest reported to date for such cells. Femto second laser studies combined with photo-induced absorption measurements showed charge separation to proceed via hole injection from the excited (CH3NH3)PbI3 NPs into the spiro-MeOTAD followed by electron transfer to the mesoscopic TiO2 film. The use of a solid hole conductor dramatically improved the device stability compared to (CH3NH3)PbI3 -sensitized liquid junction cells. PMID:22912919

  9. Propylthiouracil, Perchlorate, and Thyroid-Stimulating Hormone Modulate High Concentrations of Iodide Instigated Mitochondrial Superoxide Production in the Thyroids of Metallothionein I/II Knockout Mice

    Directory of Open Access Journals (Sweden)

    Qi Duan

    2016-03-01

    Full Text Available BackgroundIncreased oxidative stress has been suggested as one of the underlying mechanisms in iodide excess-induced thyroid disease. Metallothioneins (MTs are regarded as scavengers of reactive oxygen species (ROS in oxidative stress. Our aim is to investigate the effects of propylthiouracil (PTU, a thyroid peroxidase inhibitor, perchlorate (KClO4, a competitive inhibitor of iodide transport, and thyroid stimulating hormone (TSH on mitochondrial superoxide production instigated by high concentrations of iodide in the thyroids of MT-I/II knockout (MT-I/II KO mice.MethodsEight-week-old 129S7/SvEvBrd-Mt1tm1Bri Mt2tm1Bri/J (MT-I/II KO mice and background-matched wild type (WT mice were used.ResultsBy using a mitochondrial superoxide indicator (MitoSOX Red, lactate dehydrogenase (LDH release, and methyl thiazolyl tetrazolium (MTT assay, we demonstrated that the decreased relative viability and increased LDH release and mitochondrial superoxide production induced by potassium iodide (100 µM can be relieved by 300 µM PTU, 30 µM KClO4, or 10 U/L TSH in the thyroid cell suspensions of both MT-I/II KO and WT mice (P<0.05. Compared to the WT mice, a significant decrease in the relative viability along with a significant increase in LDH release and mitochondrial superoxide production were detected in MT-I/II KO mice(P<0.05.ConclusionWe concluded that PTU, KClO4, or TSH relieved the mitochondrial oxidative stress induced by high concentrations of iodide in the thyroids of both MT-I/II KO and WT mice. MT-I/II showed antioxidant effects against high concentrations of iodide-induced mitochondrial superoxide production in the thyroid.

  10. Occurrence of perchlorate and thiocyanate in human serum from e-waste recycling and reference sites in Vietnam: association with thyroid hormone and iodide levels.

    Science.gov (United States)

    Eguchi, Akifumi; Kunisue, Tatsuya; Wu, Qian; Trang, Pham Thi Kim; Viet, Pham Hung; Kannan, Kurunthachalam; Tanabe, Shinsuke

    2014-07-01

    Perchlorate (ClO4 (-)) and thiocyanate (SCN(-)) interfere with iodide (I(-)) uptake by the sodium/iodide symporter, and thereby these anions may affect the production of thyroid hormones (THs) in the thyroid gland. Although human exposure to perchlorate and thiocyanate has been studied in the United States and Europe, few investigations have been performed in Asian countries. In this study, we determined concentrations of perchlorate, thiocyanate, and iodide in 131 serum samples collected from 2 locations in Northern Vietnam, Bui Dau (BD; electrical and electronic waste [e-waste] recycling site) and Doung Quang (DQ; rural site) and examined the association between serum levels of these anions with levels of THs. The median concentrations of perchlorate, thiocyanate, and iodide detected in the serum of Vietnamese subjects were 0.104, 2020, and 3.11 ng mL(-1), respectively. Perchlorate levels were significantly greater in serum of the BD population (median 0.116 ng mL(-1)) than those in the DQ population (median 0.086 ng mL(-1)), which indicated greater exposure from e-waste recycling operations by the former. Serum concentrations of thiocyanate were not significantly different between the BD and DQ populations, but increased levels of this anion were observed among smokers. Iodide was a significant positive predictor of serum levels of FT3 and TT3 and a significant negative predictor of thyroid-stimulating hormone in males. When the association between serum levels of perchlorate or thiocyanate and THs was assessed using a stepwise multiple linear regression model, no significant correlations were found. In addition to greater concentrations of perchlorate detected in the e-waste recycling population, however, given that lower concentrations of iodide were observed in the serum of Vietnamese females, detailed risk assessments on TH homeostasis for females inhabiting e-waste recycling sites, especially for pregnant women and their neonates, are required.

  11. Selective Sensing of Fe(3+) and Al(3+) Ions and Detection of 2,4,6-Trinitrophenol by a Water-Stable Terbium-Based Metal-Organic Framework.

    Science.gov (United States)

    Cao, Li-Hui; Shi, Fang; Zhang, Wen-Min; Zang, Shuang-Quan; Mak, Thomas C W

    2015-10-26

    A water-stable luminescent terbium-based metal-organic framework (MOF), {[Tb(L1 )1.5 (H2 O)]⋅3 H2 O}n (Tb-MOF), with rod-shaped secondary building units (SBUs) and honeycomb-type tubular channels has been synthesized and structurally characterized by single-crystal X-ray diffraction. The high green emission intensity and the microporous nature of the Tb-MOF indicate that it can potentially be used as a luminescent sensor. In this work, we show that Tb-MOF can selectively sense Fe(3+) and Al(3+) ions from mixed metal ions in water through different detection mechanisms. In addition, it also exhibits high sensitivity for 2,4,6-trinitrophenol (TNP) in the presence of other nitro aromatic compounds in aqueous solution by luminescence quenching experiments. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. The biogeochemical effect of seaweeds upon close-to natural concentrations of dissolved iodate and iodide in seawater Preliminary study with Laminaria digitata and Fucus serratus

    Science.gov (United States)

    Truesdale, Victor W.

    2008-06-01

    Toward assessing the biogeochemical significance of seaweeds in relation to dissolved iodine in seawater, the effect of whole seaweeds ( Laminaria digitata and Fucus serratus) upon iodide and iodate, at essentially natural concentrations, has been studied. The weeds were carefully removed from the sub-littoral zone of the Menai Straits and exposed to iodide and iodate at their natural temperature (6 °C), but under continuous illumination. Laminaria digitata was found to decrease the concentration of iodate with an exponential rate constant of 0.008-0.24 h -1. This is a newly discovered process which, if substantiated, will require an entirely new mechanism. Generally, apparent iodide concentration increased except in a run with seawater augmented with iodide, where it first decreased. The rate constant for loss of iodide was 0.014-0.16 h -1. Meanwhile, F. serratus was found not to decrease iodate concentrations, as did L. digitata. Indeed, after ˜30 h iodate concentrations increased, suggesting that the weed may take in iodide before oxidising and releasing it. If substantiated, this finding may offer a way into one of the most elusive of processes within the iodine cycle - iodide oxidation. With both seaweeds sustained long-term increases of apparent iodide concentration are most easily explained as a secretion by the weeds of organic matter which is capable of reducing the Ce(IV) reagent used in determination of total iodine. Modelling of the catalytic method used is provided to support this contention. The possibility of developing this to measure the strain that seaweeds endure in this kind of biogeochemical flux experiment is discussed. A Chemical Oxygen Demand type of approach is applied using Ce(IV) as oxidant. The results of the iodine experiments are contrasted with the several investigations of 131I interaction with seaweeds, which have routinely used discs of weed cut from the frond. It is argued that experiments conducted with stable iodine may

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-10-16

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

  14. Tandem oxidation/rearrangement of beta-ketoesters to tartronic esters with molecular oxygen catalyzed by calcium iodide under visible light irradiation with fluorescent lamp.

    Science.gov (United States)

    Kanai, Naohiko; Nakayama, Hiroki; Tada, Norihiro; Itoh, Akichika

    2010-05-07

    It was found that beta-ketoesters were directly transformed to the corresponding alpha-hydroxymalonic esters, tartronic esters, with molecular oxygen catalyzed by calcium iodide under visible light irradiation from fluorescent lamp. This reaction includes tandem oxidation/rearrangement and has received much attention from the viewpoint of reduction of energy consumption, labor, and solvents.

  15. Radioiodide imaging and radiovirotherapy of multiple myeloma using VSV(Delta51)-NIS, an attenuated vesicular stomatitis virus encoding the sodium iodide symporter gene.

    Science.gov (United States)

    Goel, Apollina; Carlson, Stephanie K; Classic, Kelly L; Greiner, Suzanne; Naik, Shruthi; Power, Anthony T; Bell, John C; Russell, Stephen J

    2007-10-01

    Multiple myeloma is a radiosensitive malignancy that is currently incurable. Here, we generated a novel recombinant vesicular stomatitis virus [VSV(Delta51)-NIS] that has a deletion of methionine 51 in the matrix protein and expresses the human sodium iodide symporter (NIS) gene. VSV(Delta51)-NIS showed specific oncolytic activity against myeloma cell lines and primary myeloma cells and was able to replicate to high titers in myeloma cells in vitro. Iodide uptake assays showed accumulation of radioactive iodide in VSV(Delta51)-NIS-infected myeloma cells that was specific to the function of the NIS transgene. In bg/nd/xid mice with established subcutaneous myeloma tumors, administration of VSV(Delta51)-NIS resulted in high intratumoral virus replication and tumor regression. VSV-associated neurotoxicity was not observed. Intratumoral spread of the infection was monitored noninvasively by serial gamma camera imaging of (123)I-iodide biodistribution. Dosimetry calculations based on these images pointed to the feasibility of combination radiovirotherapy with VSV(Delta51)-NIS plus (131)I. Immunocompetent mice with syngeneic 5TGM1 myeloma tumors (either subcutaneous or orthotopic) showed significant enhancements of tumor regression and survival when VSV(Delta51)-NIS was combined with (131)I. These results show that VSV(Delta51)-NIS is a safe oncolytic agent with significant therapeutic potential in multiple myeloma.

  16. Use of dimethyl carbonate as a solvent greatly enhances the biaryl coupling of aryl iodides and organoboron reagents without adding any transition metal catalysts.

    Science.gov (United States)

    Inamoto, Kiyofumi; Hasegawa, Chisa; Hiroya, Kou; Kondo, Yoshinori; Osako, Takao; Uozumi, Yasuhiro; Doi, Takayuki

    2012-03-18

    The coupling reaction of aryl iodides with arylboronic acids to give biaryl compounds can be efficiently performed without adding a transition metal catalyst. The key to success is the use of dimethyl carbonate as a solvent. This finding provides a new strategy for constructing a biaryl linkage.

  17. Oxidation of iodide and iodine on birnessite (delta-MnO2) in the pH range 4-8.

    Science.gov (United States)

    Allard, Sébastien; von Gunten, Urs; Sahli, Elisabeth; Nicolau, Rudy; Gallard, Hervé

    2009-08-01

    The oxidation of iodide by synthetic birnessite (delta-MnO(2)) was studied in perchlorate media in the pH range 4-8. Iodine (I(2)) was detected as an oxidation product that was subsequently further oxidized to iodate (IO(3)(-)). The third order rate constants, second order on iodide and first order on manganese oxide, determined by extraction of iodine in benzene decreased with increasing pH (6.3-7.5) from 1790 to 3.1M(-2) s(-1). Both iodine and iodate were found to adsorb significantly on birnessite with an adsorption capacity of 12.7 microM/g for iodate at pH 5.7. The rate of iodine oxidation by birnessite decreased with increasing ionic strength, which resulted in a lower rate of iodate formation. The production of iodine in iodide-containing waters in contact with manganese oxides may result in the formation of undesired iodinated organic compounds (taste and odor, toxicity) in natural and technical systems. The probability of the formation of such compounds is highest in the pH range 5-7.5. For pH iodine is quickly oxidized to iodate, a non-toxic and stable sink for iodine. At pH >7.5, iodide is not oxidized to a significant extent.

  18. The Effect of Temperature and Ionic Strength on the Oxidation of Iodide by Iron(III): A Clock Reaction Kinetic Study

    Science.gov (United States)

    Bauer, Jurica; Tomisic, Vladislav; Vrkljan, Petar B. A.

    2012-01-01

    A laboratory exercise has recently been reported in which the students use the initial rates method based on the clock reaction approach to deduce the rate law and propose a reaction mechanism for the oxidation of iodide by iron(III) ions. The same approach is used in the exercise proposed herein; the students determine the dependence of the…

  19. Sequential injection spectrophotometric determination of trace amounts of iodide by its catalytic effect on the 4,4'-methylenebis(N,N-dimethylaniline)-chloramine-T reaction.

    Science.gov (United States)

    Tesfaldet, Zeriet O; van Staden, Jacobus F; Stefan, Raluca I

    2004-12-15

    A simple and sensitive sequential injection spectrophotometric procedure is proposed for the determination of trace amounts of iodide in pharmaceutical preparations. The method is based on the catalytic effect of iodide on the (tetra base) 4,4'-methylenebis(N,N-dimethylaniline)-chloramine-T reaction in acidic solution. The method involves a sequential aspiration of 255mul sample/standard followed by 170mul tetra base and then 128mul chloramine-T solutions into a carrier stream to be stacked inside a holding coil and flow reversed through a reaction coil towards a detector. The resulting colored compound is measured at 600nm using an UV/Vis-spectrophotometer. All the parameters that affect the reaction were evaluated and the calibration curve is linear over a range of 0.1-6.0mugl(-1) of iodide concentration with detection limit of 0.05mugl(-1). A sample throughput of 80 samples per hour and relative standard deviation of less than 2.0% was achieved. The method is successfully applied for the determination of iodide in three different samples (tablets).

  20. 1-Heptyl-1,3,6,8-tetraazatricyclo[4.3.1.13,8]undecan-1-ium iodide

    Directory of Open Access Journals (Sweden)

    Karla Fejfarová

    2011-10-01

    Full Text Available The title compound C14H29N4+·I− salt, was obtained by the reaction of cage adamanzane-type aminal 1,3,6,8-tetraazatricyclo[4.3.1.13,8]undecane with heptyl iodide. In the cation, the bond lengths and angles are within normal ranges, except for one N—C(ring bond distance of 1.542 (3 Å, which is unexpectedly long compared with related compounds. In the crystal, ions are linked through C—H...I hydrogen bonds. The crystal studied was a non-merohedral twin with a minor twin domain of 6.56 (5%.

  1. Two-dimensional simulation of hydrogen iodide decomposition reaction using fluent code for hydrogen production using nuclear technology

    Directory of Open Access Journals (Sweden)

    Jung-Sik Choi

    2015-06-01

    Full Text Available The operating characteristics of hydrogen iodide (HI decomposition for hydrogen production were investigated using the commercial computational fluid dynamics code, and various factors, such as hydrogen production, heat of reaction, and temperature distribution, were studied to compare device performance with that expected for device development. Hydrogen production increased with an increase of the surface-to-volume (STV ratio. With an increase of hydrogen production, the reaction heat increased. The internal pressure and velocity of the HI decomposer were estimated through pressure drop and reducing velocity from the preheating zone. The mass of H2O was independent of the STV ratio, whereas that of HI decreased with increasing STV ratio.

  2. The antimicrobial effect of apical box versus apical cone preparation using iodine potassium iodide as root canal dressing

    DEFF Research Database (Denmark)

    Markvart, Merete; Dahlén, Gunnar; Reit, Claes-Erik

    2013-01-01

    Abstract Purpose. The purpose was to study the reduction of intra-canal microflora in premolars with apical periodontitis instrumented with either apical box or apical cone preparation and to provide measurements of intervention effects to allow proper power calculation in future clinical trials......OCl (12 ml). Lastly, the canals were filled with 17% EDTA (2 × 30 s) and 5% iodine potassium iodide (IKI) for 10 min. The canals were sampled for micro-organisms on four occasions: before instrumentation, after instrumentation, after application of IKI dressing and at the beginning of the second...... in 88% of the teeth. Growth was classified as none in 35% of the teeth after instrumentation and in 50% after the application of IKI. Irrespective of the time of sampling, no significant difference in microbial growth reduction was observed between the two types of apical preparation. Based on the 1...

  3. Substrate effects on photoluminescence and low temperature phase transition of methylammonium lead iodide hybrid perovskite thin films

    Science.gov (United States)

    Shojaee, S. A.; Harriman, T. A.; Han, G. S.; Lee, J.-K.; Lucca, D. A.

    2017-07-01

    We examine the effects of substrates on the low temperature photoluminescence (PL) spectra and phase transition in methylammonium lead iodide hybrid perovskite (CH3NH3PbI3) thin films. Structural characterization at room temperature with X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy indicated that while the chemical structure of films deposited on glass and quartz was similar, the glass substrate induced strain in the perovskite films and suppressed the grain growth. The luminescence response and phase transition of the perovskite thin films were studied by PL spectroscopy. The induced strain was found to affect both the room temperature and low temperature PL spectra of the hybrid perovskite films. In addition, it was found that the effects of the glass substrate inhibited a tetragonal to orthorhombic phase transition such that it occurred at lower temperatures.

  4. Polarization and Dielectric Study of Methylammonium Lead Iodide Thin Film to Reveal its Nonferroelectric Nature under Solar Cell Operating Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Hoque, Md Nadim Ferdous; Yang, Mengjin; Li, Zhen; Islam, Nazifah; Pan, Xuan; Zhu, Kai; Fan, Zhaoyang

    2016-07-08

    Researchers have debated whether methylammonium lead iodide (MAPbI3), with a perovskite crystal structure, is ferroelectric and therefore contributes to the current--voltage hysteresis commonly observed in hybrid perovskite solar cells (PSCs). We thoroughly investigated temperature-dependent polarization, dielectric, and impedance spectroscopies, and we found no evidence of ferroelectric effect in a MAPbI3 thin film at normal operating conditions. Therefore, the effect does not contribute to the hysteresis in PSCs, whereas the large component of ionic migration observed may play a critical role. Our temperature-based polarization and dielectric studies find that MAPbI3 exhibits different electrical behaviors below and above ca. 45 degrees C, suggesting a phase transition around this temperature. In particular, we report the activation energies of ionic migration for the two phases and temperature-dependent permittivity of MAPbI3. This study contributes to the understanding of the material properties and device performance of hybrid perovskites.

  5. Evidence of tellurium iodide compounds in a power-ramped irradiated UO{sub 2} fuel rod

    Energy Technology Data Exchange (ETDEWEB)

    Desgranges, L., E-mail: lionel.desgranges@cea.fr [CEA/DEN/DEC CE Cadarache, 13108 Saint-Paul-lez-Durance (France); Riglet-Martial, Ch.; Aubrun, I.; Pasquet, B.; Roure, I.; Lamontagne, J.; Blay, T. [CEA/DEN/DEC CE Cadarache, 13108 Saint-Paul-lez-Durance (France)

    2013-06-15

    The existence of tellurium iodide compounds was evidenced in power-ramped UO{sub 2} irradiated fuel by means of post-test SIMS analysis that showed both volatile fission product releases from the pellet centre and precipitates composed of these volatile fission products on the fuel periphery. Thermodynamic calculations confirmed the stability of TeI{sub x} gaseous phases in equilibrium with irradiated UO{sub 2}. Both the experimental and theoretical results offer a strong incentive to consider TeI{sub x} compounds for stress corrosion cracking (SCC) of the cladding during a power ramp instead of CsI since TeI{sub x} compounds are more corrosive to Zircaloy cladding than CsI.

  6. A carrier transport model in the high-resistance state of lead-methylamine iodide-based resistive memory devices

    Directory of Open Access Journals (Sweden)

    Yongwoo Kwon

    2017-08-01

    Full Text Available Methylamine lead iodide (CH3NH3PbI3, which has recently been in the spotlight as a solar cell material, has also recently shown promise for use as an active material in resistive memory cells with ultralow operation voltages, good transparencies, and flexibilities. The material’s defects, which govern its properties, differ vastly depending on the fabrication process. However, the defect chemistry is not yet entirely understood. We have therefore established a macroscopic transport model with defect-related model parameters, such as trap density, trap energy level, and Fermi level, in order to estimate these parameters for fabricated samples based on their electrical data. Our model will serve as an efficient way to analyze the properties of the active material.

  7. High Momentum Particle Identification Detector The Study of Cesium Iodide Quantum Efficiency Dependency on Substrate Material, Temperature and Quartz Window

    CERN Document Server

    Wisna, Gde Bimananda M

    2014-01-01

    The Cesium Iodide (CsI) is used as a material for detecting Cherenkov radiation produced by high momentum particle in High Momentum Particle Identification Detector (HMPID) at ALICE Experiment at CERN. This work provides investigation and analysis of The Quantum Efficiency (QE) result of CsI which is deposited on five samples substrates such as copper passivated red, copper passivated yellow, aluminium, copper coated with nickel and copper coated with nickel then coated with gold. The measurement of five samples is held under temperature $60^{0}$ C and $25^{0}$ C (room temperature) and also with optical quartz window which can be adjusted to limit the wavelength range which reach the CsI. The result shows there are dependency of substrate, temperature due to enhancement effect and also quartz windows usage on QE of CsI. The results of five samples is then compared and analyzed.

  8. Femtosecond real-time probing of reactions MMXVII: The predissociation of sodium iodide in the A 0+ state

    Science.gov (United States)

    Rasskazov, Gennady; Nairat, Muath; Magoulas, Ilias; Lozovoy, Vadim V.; Piecuch, Piotr; Dantus, Marcos

    2017-09-01

    We revisit the femtosecond transition-state spectroscopy of sodium iodide taking advantage of modern lasers and pulse-shaping to better map the low-lying electronic states, some forming predissociative wells through curve crossings. We also carry out high-level ab initio multi-reference configuration interaction calculations including spin-orbit coupling terms and using large correlation-consistent basis sets to arrive at accurate ground- and excited-state potential energy curves of NaI. Density matrix calculations employing vibrational wave functions determined from the ab initio X 0+ and A 0+ potentials are used to simulate time dependent wave packet dynamics of NaI pumped to the A 0+ state.

  9. Benchmark Gamma Spectroscopy Measurements of Uranium Hexafluoride in Aluminmum Pipe with a Sodium Iodide Detector

    Energy Technology Data Exchange (ETDEWEB)

    March-Leuba, Jose A [ORNL; Uckan, Taner [ORNL; Gunning, John E [ORNL; Brukiewa, Patrick D [ORNL; Upadhyaya, Belle R [ORNL; Revis, Stephen M [ORNL

    2010-01-01

    monitor (FM) and an enrichment monitor (EM). Development of the FM is primarily the responsibility of Oak Ridge National Laboratory, and development of the EM is primarily the responsibility of Los Alamos National Laboratory. The FM will measure {sup 235}U mass flow rate by combining information from measuring the UF{sub 6} volumetric flow rate and the {sup 235}U density. The UF{sub 6} flow rate will be measured using characteristics of the process pumps used in product and tail UF{sub 6} header process lines of many GCEPs, and the {sup 235}U density will be measured using commercially available sodium iodide (NaI) gamma ray scintillation detectors. This report describes the calibration of the portion of the FM that measures the {sup 235}U density. Research has been performed to define a methodology and collect data necessary to perform this calibration without the need for plant declarations. The {sup 235}U density detector is a commercially available system (GammaRad made by Amptek, www.amptek.com) that contains the NaI crystal, photomultiplier tube, signal conditioning electronics, and a multichannel analyzer (MCA). Measurements were made with the detector system installed near four {sup 235}U sources. Two of the sources were made of solid uranium, and the other two were in the form of UF{sub 6} gas in aluminum piping. One of the UF{sub 6} gas sources was located at ORNL and the other at LANL. The ORNL source consisted of two pipe sections (schedule 40 aluminum pipe of 4-inch and 8-inch outside diameter) with 5.36% {sup 235}U enrichment, and the LANL source was a 4-inch schedule 40 aluminum pipe with 3.3% {sup 235}U enrichment. The configurations of the detector on these test sources, as well as on long straight pipe configurations expected to exist at GCEPs, were modeled using the computer code MCNP. The results of the MCNP calculations were used to define geometric correction factors between the test source and the GCEP application. Using these geometric correction

  10. Tumor suppressor protein p53 exerts negative transcriptional regulation on human sodium iodide symporter gene expression in breast cancer.

    Science.gov (United States)

    Kelkar, Madhura G; Thakur, Bhushan; Derle, Abhishek; Chatterjee, Sushmita; Ray, Pritha; De, Abhijit

    2017-08-01

    Aberrant expression of human sodium iodide symporter (NIS) in breast cancer (BC) is well documented but the transcription factors (TF) regulating its aberrant expression is poorly known. We identify the presence of three p53 binding sites on the human NIS promoter sequence by conducting genome-wide TF analysis, and further investigate their regulatory role. The differences in transcription and translation were measured by real-time PCR, luciferase reporter assay, site-directed mutagenesis, in vivo optical imaging, and chromatin immunoprecipitation. The relation of NIS and p53 in clinical samples was judged by TCGA data analysis and immunohistochemistry. Overexpression of wild-type p53 as a transgene or pharmacological activation by doxorubicin drug treatment shows significant suppression of NIS transcription in multiple BC cell types which also results in lowered NIS protein content and cellular iodide intake. NIS repression by activated p53 is further confirmed by non-invasive bioluminescence imaging in live cell and orthotropic tumor model. Abrogation of p53-binding sites by directional mutagenesis confirms reversal of transcriptional activity in wild-type p53-positive BC cells. We also observe direct binding of p53 to these sites on the human NIS promoter. Importantly, TCGA data analysis of NIS and p53 co-expression registers an inverse relationship between the two candidates. Our data for the first time highlight the role of p53 as a negative regulator of functional NIS expression in BC, where the latter is a potential targeted radioiodine therapy candidate. Thus, the study provides an important insight into prospective clinical application of this approach that may significantly impact the patient with mutant versus wild-type p53 profile.

  11. Potentiation by potassium iodide reveals that the anionic porphyrin TPPS4 is a surprisingly effective photosensitizer for antimicrobial photodynamic inactivation.

    Science.gov (United States)

    Huang, Liyi; El-Hussein, Ahmed; Xuan, Weijun; Hamblin, Michael R

    2018-01-01

    We recently reported that addition of the non-toxic salt, potassium iodide can potentiate antimicrobial photodynamic inactivation of a broad-spectrum of microorganisms, producing many extra logs of killing. If the photosensitizer (PS) can bind to the microbial cells, then delivering light in the presence of KI produces short-lived reactive iodine species, while if the cells are added after light the killing is caused by molecular iodine produced as a result of singlet oxygen-mediated oxidation of iodide. In an attempt to show the importance of PS-bacterial binding, we compared two charged porphyrins, TPPS4 (thought to be anionic and not able to bind to Gram-negative bacteria) and TMPyP4 (considered cationic and well able to bind to bacteria). As expected TPPS4+light did not kill Gram-negative Escherichia coli, but surprisingly when 100mM KI was added, it was highly effective (eradication at 200nM+10J/cm 2 of 415nm light). TPPS4 was more effective than TMPyP4 in eradicating the Gram-positive bacteria, methicillin-resistant Staphylococcus aureus and the fungal yeast Candida albicans (regardless of KI). TPPS4 was also highly active against E. coli after a centrifugation step when KI was added, suggesting that the supposedly anionic porphyrin bound to bacteria and Candida. This was confirmed by uptake experiments. We compared the phthalocyanine tetrasulfonate derivative (ClAlPCS4), which did not bind to bacteria or allow KI-mediated killing of E. coli after a spin, suggesting it was truly anionic. We conclude that TPPS4 behaves as if it has some cationic character in the presence of bacteria, which may be related to its delivery from suppliers in the form of a dihydrochloride salt. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Leaching of Au, Ag, and Pd from waste printed circuit boards of mobile phone by iodide lixiviant after supercritical water pre-treatment.

    Science.gov (United States)

    Xiu, Fu-Rong; Qi, Yingying; Zhang, Fu-Shen

    2015-07-01

    Precious metals are the most attractive resources in waste printed circuit boards (PCBs) of mobile phones. In this work, an alternative process for recovering Au, Ag, and Pd from waste PCBs of mobile phones by supercritical water oxidation (SCWO) pre-treatment combined with iodine-iodide leaching process was developed. In the process, the waste PCBs of mobile phones were pre-treated in supercritical water, then a diluted hydrochloric acid leaching (HL) process was used to recovery the Cu, whose leaching efficiency was approximately 100%, finally the resulting residue was subjected to the iodine-iodide leaching process for recovering the Au, Ag, and Pd. Experimental results indicated that SCWO pre-treatment temperature, time, and pressure had significant influence on the Au, Ag, and Pd leaching from (SCWO+HL)-treated waste PCBs. The optimal SCWO pre-treatment conditions were 420°C and 60min for Au and Pd, and 410°C and 30min for Ag. The optimum dissolution parameters for Au, Pd, and Ag in (SCWO+HL)-treated PCBs with iodine-iodide system were leaching time of 120min (90min for Ag), iodine/iodide mole ratio of 1:5 (1:6 for Ag), solid-to-liquid ratio (S/L) of 1:10g/mL (1:8g/mL for Ag), and pH of 9, respectively. It is believed that the process developed in this study is environment friendly for the recovery of Au, Ag, and Pd from waste PCBs of mobile phones by SCWO pre-treatment combined with iodine-iodide leaching process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Sodium terbium(III polyphosphate

    Directory of Open Access Journals (Sweden)

    Abdelghani Oudahmane

    2010-04-01

    Full Text Available Single crystals of the title compound, NaTb(PO34, were obtained by solid-state reaction. This compound belongs to type II of long-chain polyphosphates with the general formula AIBIII(PO34. It is isotypic with the NaNd(PO34 and NaEr(PO34 homologues. The crystal structure is built up of infinite crenelated chains of corner-sharing PO4 tetrahedra with a repeating unit of four tetrahedra. These chains, extending parallel to [100], are linked by isolated TbO8 square antiprisms, forming a three-dimensional framework. The Na+ ions are located in channels running along [010] and are surrounded by six oxygen atoms in a distorted octahedral environment within a cut-off distance <2.9 Å.

  14. Chemical conversion of cisplatin and carboplatin with histidine in a model protein crystallized under sodium iodide conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tanley, Simon W. M.; Helliwell, John R., E-mail: john.helliwell@manchester.ac.uk [University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom)

    2014-08-29

    Crystals of HEWL with cisplatin and HEWL with carboplatin grown in sodium iodide conditions both show a partial chemical transformation of cisplatin or carboplatin to a transiodoplatin (PtI{sub 2}X{sub 2}) form. The binding is only at the N{sup δ} atom of His15. A further Pt species (PtI{sub 3}X) is also seen, in both cases bound in a crevice between symmetry-related protein molecules. Cisplatin and carboplatin are platinum anticancer agents that are used to treat a variety of cancers. Previous X-ray crystallographic studies of carboplatin binding to histidine in hen egg-white lysozyme (HEWL) showed a partial chemical conversion of carboplatin to cisplatin owing to the high sodium chloride concentration used in the crystallization conditions. Also, the co-crystallization of HEWL with carboplatin in sodium bromide conditions resulted in the partial conversion of carboplatin to the transbromoplatin form, with a portion of the cyclobutanedicarboxylate (CBDC) moiety still present. The results of the co-crystallization of HEWL with cisplatin or carboplatin in sodium iodide conditions are now reported in order to determine whether the cisplatin and carboplatin converted to the iodo form, and whether this took place in a similar way to the partial conversion of carboplatin to cisplatin in NaCl conditions or to transbromoplatin in NaBr conditions as seen previously. It is reported here that a partial chemical transformation has taken place to a transplatin form for both ligands. The NaI-grown crystals belonged to the monoclinic space group P2{sub 1} with two molecules in the asymmetric unit. The chemically transformed cisplatin and carboplatin bind to both His15 residues, i.e. in each asymmetric unit. The binding is only at the N{sup δ} atom of His15. A third platinum species is also seen in both conditions bound in a crevice between symmetry-related molecules. Here, the platinum is bound to three I atoms identified based on their anomalous difference electron densities

  15. Release of iodine in the atmospheric oxidation of alkyl iodides and the fates of iodinated alkoxy radicals

    Science.gov (United States)

    Cotter, E. S. N.; Booth, N. J.; Canosa-Mas, C. E.; Wayne, R. P.

    This paper describes a study of the products of the Cl-atom-initiated oxidation of three alkyl iodides, RI=CH 3I, C 2H 5I, and 2-C 3H 7I, carried out in synthetic air at atmospheric pressure and at room temperature. Fourier-transform infrared spectroscopy was used to follow the decay of reactants and subsequent formation of products. The primary step proceeds via two channels, one of which yields HCl and an iodinated alkyl radical, and the other I atoms and an alkyl chloride. Quantitative analysis of the product yields, together with an assessment of the formation of HCl in secondary processes, allowed the fractional branching into the two channels to be calculated. The channel yielding HCl from RI constitutes a fraction 0.59, 0.93, and 0.68 for R=CH 3, C 2H 5, and 2-C 3H 7. The iodinated alkyl radical forms first a peroxy, and then an alkoxy, radical in the presence of air. The final products CH 2O, CH 3CHO, and CH 3COCH 3 were observed as expected for the decomposition of these radicals with RI=CH 3I, C 2H 5I, and 2-C 3H 7I, and the fractions of the alkoxy radicals fragmenting to the carbonyl compounds were 0.88, 0.57, and 0.86, respectively. Atomic iodine is formed concomitantly with the carbonyl species, so that these fractions also indicate the yield of I atoms in the secondary process. Alternative reaction pathways for the iodinated alkoxy radicals, in particular reaction with O 2, are evaluated and discussed. The yields of I atoms in the primary and secondary steps, taken in combination with kinetic data, make it possible to estimate the contribution of the Cl-initiated oxidation of the alkyl halides to I-atom production in the atmosphere (and, making certain assumptions, the analogous contribution from OH-initiated oxidation). Radical-initiated processes might augment the photolytic yield of I atoms from simple alkyl iodides: the maximum enhancements lie between 5% (CH 3I) and more than 30% (2-C 3H 7I).

  16. Synthesis, spectral characterization and in vitro antibacterial evaluation and Petra/Osiris/Molinspiration analyses of new Palladium(II iodide complexes with thioamides

    Directory of Open Access Journals (Sweden)

    Shafqat Nadeem

    2016-09-01

    Full Text Available The paper emphasizes on the synthesis of Palladium(II iodide complexes containing based ligands. The new compounds of general formulae [Pd(L4]I2 where L = Thiourea (Tu, Methylthiourea (Metu, Dimethylthiourea (Dmtu, Tetramethylthiourea (Tmtu, Imidazolidine-2-thione (Imt, Mercaptopyridine (Mpy, Mercaptopyrimidine (Mpm, and Thionicotinamide (Tna were prepared simply by reacting K2[PdCl4] with the corresponding thioamides in 1:2 M ratio and then with 2 equivalents Potassium iodide. The complexes were characterized by elemental analysis and spectroscopic techniques (IR, 1H and13C NMR. All the synthesized complexes were screened for antibacterial activity and some of compounds have shown good activities against both gram positive and gram negative bacteria. POM analyses reveal that the compounds are only slightly toxic and present a potential for antibacterial activity. Moreover, they have 16–23% drug score which is an important parameter for the compound possessing the drug properties.

  17. The Effect of Lithium Iodide to the Properties of Carboxymethyl κ-Carrageenan/Carboxymethyl Cellulose Polymer Electrolyte and Dye-Sensitized Solar Cell Performance

    OpenAIRE

    Siti Rudhziah Che Balian; Azizan Ahmad; Nor Sabirin Mohamed

    2016-01-01

    This study was undertaken to investigate the solid biopolymer electrolytes based on a carboxymethyl κ-carrageenan/carboxymethyl cellulose blend complexed with lithium iodide of various weight ratios. The complexation of the doping salt with the polymer blend was confirmed by Fourier transform infrared spectroscopy. Ionic conductivity of the film was determined by impedance spectroscopy in the frequency range of 10 Hz to 4 MHz and in the temperature range of 303–338 K. The ionic conductivity i...

  18. Effect of iodide on Fas, Fas-ligand and Bcl-w mRNA expression in thyroid of NOD mice pretreated with methimazole

    Directory of Open Access Journals (Sweden)

    L.H.B. Boechat

    2002-03-01

    Full Text Available Nonobese diabetic (NOD mice and a derived strain, NOD.H.2h4, have been used as a model for experimental spontaneous thyroiditis and thyroiditis induced by iodide excess after a goiter-inducing period. Some authors have proposed that iodide, given after methimazole or propylthiouracil, is capable of inducing apoptosis in thyroid cells and that anti-thyroid drugs can modulate the expression of apoptosis components such as Fas and its ligand (Fas-L. Here we evaluated the effect of potassium iodide (20 µg/animal for 4 days, ip given to NOD mice at the 10th week of life after exposure to methimazole (1 mg/ml in drinking water from the 4th to the 10th week of life. Fas, Fas-L and Bcl-w expression were analyzed semiquantitatively by RT-PCR immediately after potassium iodide administration (group MI44D or at week 32 (MI32S. Control groups were added at 10 (C10 and 32 weeks (C32, as well as a group that received only methimazole (CM10. An increase in the expression of Fas-L and Bcl-w (P<0.01, ANOVA was observed in animals of group MI44D, while Fas was expressed at higher levels (P = 0.02 in group C32 (72.89 ± 47.09 arbitrary units when compared to group C10 (10.8 ± 8.55 arbitrary units. Thus, the analysis of Fas-L and Bcl-w expression in the MI44D group and Fas in group C32 allowed us to detect two different patterns of expression of these apoptosis components in thyroid tissue of NOD mice.

  19. 3-Methyl-4,5,6,7,8,9-hexahydrocycloocta[d][1,2,3]selenadiazol]-3-ium iodide triiodide (3/2/1

    Directory of Open Access Journals (Sweden)

    Dieter Schollmeyer

    2016-12-01

    Full Text Available The title compound, 3C9H15N2Se+·I3−·2I−, was prepared by methylation of the selenadiazole with methyl iodide. The asymmetric unit is composed of three independent selenadiazolium ions arranged in layers and connected via I3−·(I−2 anion layers. The distances between the iodine and selenium atoms are significantly shorter than the nitrogen-to-iodine distances.

  20. A Simple and efficient protocol for the synthesis of 1,4-dihydro pyridines (Hantzsch pyridines catalyzed by Germanium (IV iodide

    Directory of Open Access Journals (Sweden)

    Chandramouleswararao Jillepalli

    2014-12-01

    Full Text Available A simple and efficient protocol has been developed for the synthesis of Hantzsch pyridines. In the reported synthesis, a variety of aldehydes undergo smooth condensation reaction with ethyl acetoacetate and ammonium acetate in presence of Germanium (IV iodide in acetonitrile. This method is applicable to a variety of substrates to afford the corresponding 1,4-dihydropyridines in one-pot reaction in excellent yields.

  1. Water to atmosphere fluxes of {sup 131}I in relation with alkyl-iodide compounds from the Seine Estuary (France)

    Energy Technology Data Exchange (ETDEWEB)

    Connan, Olivier [Laboratoire de Radioecologie de Cherbourg-Octeville, Institut de Radioprotection et de Surete nucleaire (IRSN), Service d' Etudes et du Comportement des Radionucleides dans l' Environnement (SECRE), rue Max Pol Fouchet, 50130 Cherbourg-Octeville (France)], E-mail: olivier.connan@irsn.fr; Tessier, Emmanuel [Laboratoire de Chimie Analytique et Bio-Inorganique et Environnement, UMR CNRS universite de Pau et des Pays de l' Adour, Helioparc Pau Pyrenees, 2 Avenue Pierre Angot, 64053 Pau Cedex 9 (France); Maro, Denis [Laboratoire de Radioecologie de Cherbourg-Octeville, Institut de Radioprotection et de Surete nucleaire (IRSN), Service d' Etudes et du Comportement des Radionucleides dans l' Environnement (SECRE), rue Max Pol Fouchet, 50130 Cherbourg-Octeville (France); Amouroux, David [Laboratoire de Chimie Analytique et Bio-Inorganique et Environnement, UMR CNRS universite de Pau et des Pays de l' Adour, Helioparc Pau Pyrenees, 2 Avenue Pierre Angot, 64053 Pau Cedex 9 (France); Hebert, Didier; Rozet, Marianne; Voiseux, Claire; Solier, Luc [Laboratoire de Radioecologie de Cherbourg-Octeville, Institut de Radioprotection et de Surete nucleaire (IRSN), Service d' Etudes et du Comportement des Radionucleides dans l' Environnement (SECRE), rue Max Pol Fouchet, 50130 Cherbourg-Octeville (France)

    2008-07-15

    This study presents an original work on measurements of stable and radioactive iodinated species in the Seine estuary (France), with estimates fluxes of volatile gaseous species from water to the atmosphere. Various iodinated compounds were identified in water and air in particular {sup 131}I in water, what is unusual. Concentrations and behaviour of iodinated elements in the Seine estuary seem similar to what has been observed in other European estuaries. MeI (Methyl Iodide) and Total Volatile Iodine (TVI) fluxes from water to air vary between 392 and 13949 pmol m{sup -2} d{sup -1} and between 1279 and 16484 pmol m{sup -2} d{sup -1}, respectively. Water to air flux of TVI for the Seine river was estimated in the range 4-46 kg y{sup -1}. Measurements of {sup 131}I in water varying between 0.4 and 11.9 Bq m{sup -3}. Fluxes of {sup 131}I from water to atmosphere are in the range 2.4 x 10{sup 5}-1.3 x 10{sup 7} Bq y{sup -1}, close to an annual discharge of {sup 131}I by a nuclear reactor.

  2. Ionic conductivity, infrared and Raman spectroscopic studies of 1-methyl-3-propylimidazolium iodide ionic liquid with added iodine

    Energy Technology Data Exchange (ETDEWEB)

    Jerman, I.; Jovanovski, V.; Surca Vuk, A.; Hocevar, S.B.; Gaberscek, M. [National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia); Jesih, A. [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Orel, B. [National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia)], E-mail: boris.orel@ki.si

    2008-01-01

    Polyiodides (I{sub x}{sup -}, x = 3 and 5) and 2I{sup -}...I{sub 2} adducts were established from the Raman spectra study of 1-methyl-3-propylimidazolium iodide (MPIm{sup +}I{sub x}{sup -}; 1 {<=} x {<=} 5) ionic liquids containing various amounts of iodine (0 mol {<=} I{sub 2} {<=} 2 mol). The existence of I{sub 3}{sup -} and 2I{sup -}...I{sub 2} was established for 1 {<=} x {<=} 2.5, symmetric I{sub 3}{sup -} ions for x = 3, while linear and discrete I{sub 5}{sup -} was substantiated for 3 {<=} x {<=} 5. The presence of polyiodide species in MPIm{sup +}I{sub x}{sup -} (1 {<=} x {<=} 5) was correlated with an enhanced ionic conductivity, attributed to the established relay-type Grotthus mechanism. Two-step conductivity increase was also reflected in decrease of the hydrogen bond interactions between the C-H ring groups and polyiodides. While in the concentration range 1 {<=} x {<=} 3 (triiodides and tetraiodides) IR bands changed only slightly in intensity, in the concentration range x > 3 the C-H stretching bands (3040-3170 cm{sup -1}) split and the new band at 1585 cm{sup -1} appeared in the IR spectra beside the already existing Im{sup +} ring stretching mode at 1566 cm{sup -1}.

  3. Ionic and Optical Properties of Methylammonium Lead Iodide Perovskite across the Tetragonal-Cubic Structural Phase Transition.

    Science.gov (United States)

    Hoque, Md Nadim Ferdous; Islam, Nazifah; Li, Zhen; Ren, Guofeng; Zhu, Kai; Fan, Zhaoyang

    2016-09-22

    Practical hybrid perovskite solar cells (PSCs) must endure temperatures above the tetragonal-cubic structural phase transition of methylammonium lead iodide (MAPbI3 ). However, the ionic and optical properties of MAPbI3 in such a temperature range, and particularly, dramatic changes in these properties resulting from a structural phase transition, are not well studied. Herein, we report a striking contrast at approximately 45 °C in the ionic/electrical properties of MAPbI3 owing to a change of the ion activation energy from 0.7 to 0.5 eV, whereas the optical properties exhibit no particular transition except for the steady increase of the bandgap with temperature. These observations can be explained by the "continuous" nature of perovskite phase transition. We speculate that the critical temperature at which the ionic/electrical properties change, although related to crystal symmetry variation, is not necessarily the same temperature as when tetragonal-cubic structural phase transition occurs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Experimental Study of Closed System in the Chlorine Dioxide-Iodide-Sulfuric Acid Reaction by UV-Vis Spectrophotometric Method

    Directory of Open Access Journals (Sweden)

    Na Li

    2011-01-01

    Full Text Available The mole ratio r(r=[I−]0/[ClO2]0 has great influence on ClO2-I−-H2SO4 closed reaction system. By changing the initiate concentration of potassium iodide, the curve of absorbance along with the reaction time was obtained at 350 nm and 297 nm for triiodide ion, and 460 nm for iodine. The changing point of the absorbance curve's shape locates at r=6.00. For the reaction of ClO2-I− in the absence of H2SO4, the curve of absorbance along with the reaction time can be obtained at 350 nm for triiodide ion, 460 nm for iodine. The mole ratio r is equal to 1.00 is the changing point of the curve's shape no matter at which wavelength to determine the reaction. For the reaction of ClO2-I−-H+ in different pH buffer solution, the curve of absorbance along with the reaction time was recorded at 460 nm for iodine. When r is greater than 1.00, the transition point of the curve's shape locates at pH 2.0, which is also the point of producing chlorite or chloride for chlorine dioxide at different pH. When r is less than 1.00, the transition point locates at pH 7.0.

  5. Mechanical Origin of the Structural Phase Transition in Methylammonium Lead Iodide CH3NH3PbI3.

    Science.gov (United States)

    Ong, Khuong P; Goh, Teck Wee; Xu, Qiang; Huan, Alfred

    2015-02-19

    The methylammonium lead iodide perovskite (MAPbI3) is presently a desirable material for photovoltaic application. Its structure is orthorhombic at low temperature and tetragonal at room temperature. Most theoretical works have focused on either tetragonal or orthorhombic phase alone leaving a gap in the understanding of the structural phase transition in between. In this work, by ab initio calculations, we elucidate the origin of structural phase transition between these two phases. We show that there exists a critical ratio of out-of-plane to in-plane lattice constants, c/a ∼ 1.45, where at low c/a the orthorhombic Pnma phase is stable while the tetragonal I4/mcm phase is stable at high c/a. Varying the c/a ratio leads to a change of PbI6 octahedral tilting with the rotation of CH3NH3(+) cations about the NH3 component in and out of the Oxy plane. The origin of this rotation is identified. We propose that under epitaxial conditions a gradual change in structural phase of the MAPbI3 perovskite may exist and understanding its electronic properties will be beneficial toward the solar cell community.

  6. New electrochemiluminescence catalyst: Cu2O semiconductor crystal and the enhanced activity of octahedra synthesized by iodide ions coordination

    Science.gov (United States)

    Zhang, Ling; Qi, Liming; Gao, Wenyue; Niu, Wenxin; Luque, Rafael; Xu, Guobao

    2017-11-01

    Cuprous oxide (Cu2O) crystals are usually used as the photocatalysts of water splittings and carbon monoxide oxidations. Herein, we report the new catalytic properties of Cu2O to the electrochemilumenescence (ECL) reactions of luminol and oxygen. Adjusting the shape of Cu2O microcrystals from cube to octahedra also facilities the improved electrocatalytic acticity, where octahedral Cu2O microcrystals possess higher ECL signal by 25% at  ‑0.6 V (versus Ag/AgCl) at pH 7.4. The octahedral Cu2O microcrystals are synthesized by the coordination of iodide ions to the surface, which alters the crystals shapes from cubes to octahedra. Size-distribution of octahedra is improved with this mehod compared to the previous studies with only hydroxide ions as the coordinates. The catalytic activity of octahedral Cu2O crystals is expected to be compared with the noble metal nanomaterials and constructed the high-efficiency and low-cost ECL biosensors.

  7. Ionic and Optical Properties of Methylammonium Lead Iodide Perovskite across the Tetragonal-Cubic Structural Phase Transition

    Energy Technology Data Exchange (ETDEWEB)

    Hoque, Md Nadim Ferdous [Department of Electrical and Computer Engineering and Nano Tech Center, Texas Tech University, Lubbock Texas 79409 USA; Islam, Nazifah [Department of Electrical and Computer Engineering and Nano Tech Center, Texas Tech University, Lubbock Texas 79409 USA; Li, Zhen [Chemistry and Nanoscience Center, National Renewable Energy Laboratory, Golden Colorado 80401 USA; Ren, Guofeng [Department of Electrical and Computer Engineering and Nano Tech Center, Texas Tech University, Lubbock Texas 79409 USA; Zhu, Kai [Chemistry and Nanoscience Center, National Renewable Energy Laboratory, Golden Colorado 80401 USA; Fan, Zhaoyang [Department of Electrical and Computer Engineering and Nano Tech Center, Texas Tech University, Lubbock Texas 79409 USA

    2016-09-01

    Practical hybrid perovskite solar cells (PSCs) must endure temperatures above the tetragonal-cubic structural phase transition of methylammonium lead iodide (MAPbI3). However, the ionic and optical properties of MAPbI3 in such a temperature range, and particularly, dramatic changes in these properties resulting from a structural phase transition, are not well studied. Herein, we report a striking contrast at approximately 45 degrees C in the ionic/electrical properties of MAPbl3 owing to a change of the ion activation energy from 0.7 to 0.5 eV, whereas the optical properties exhibit no particular transition except for the steady increase of the bandgap with temperature. These observations can be explained by the 'continuous' nature of perovskite phase transition. We speculate that the critical temperature at which the ionic/electrical properties change, although related to crystal symmetry variation, is not necessarily the same temperature as when tetragonal-cubic structural phase transition occurs.

  8. The Synergistic Effect of Iodide and Sodium Nitrite on the Corrosion Inhibition of Mild Steel in Bicarbonate–Chloride Solution

    Science.gov (United States)

    Eyu, Gaius Debi; Will, Geoffrey; Dekkers, Willem; MacLeod, Jennifer

    2016-01-01

    The effect of potassium iodide (KI) and sodium nitrite (NaNO2 inhibitor on the corrosion inhibition of mild steel in chloride bicarbonate solution has been studied using electrochemical techniques. Potentiodynamic polarisation data suggest that, when used in combination, KI and NaNO2 function together to inhibit reactions at both the anode and the cathode, but predominantly anodic. KI/NO2− concentration ratios varied from 2:1 to 2:5; inhibition efficiency was optimized for a ratio of 1:1. The surface morphology and corrosion products were analysed using scanning electron microscopy (SEM) and X-ray diffractometry (XRD). The latter shows that the addition of I− to NO2 facilitates the formation of a passivating oxide (γ-Fe2O3) as compared to NO2− alone, decreasing the rate of metal dissolution observed in electrochemical testing. The synergistic effect of KI/NO2− inhibition was enhanced under the dynamic conditions associated with testing in a rotating disc electrode. PMID:28773991

  9. Red mercuric iodide crystals obtained by isothermal solution evaporation: Characterization for mammographic X-ray imaging detectors

    Energy Technology Data Exchange (ETDEWEB)

    Caldeira, A.M.F.; Ugucioni, J.C.; Mulato, M.

    2014-02-11

    Millimeter-sized mercury iodide crystals were obtained by the isothermal evaporation technique using dimethylformamide (DMF), diethyl-ether/DMF mixture and THF. Different concentrations (18 mM and 400 mM) and solution temperature (25–80 °C) were used to obtain varied evaporation rates (0.1×10{sup −4}–5000×10{sup −4} ml/h). Different crystal sizes and shapes were obtained by changing solvents, mixture and initial solution volume. According to X-ray diffraction the samples are monocrystalline. The top surface was investigated by SEM. Optical band-gaps above 2 eV were obtained from photoacoustic spectroscopy. Photoluminescence spectra indicated band-to-band electronic transitions, and the presence of sub-band gap states. Excitons, structural defects and the presence of impurities are discussed and correlated to the electrical measurements. Crystals obtained using pure DMF as solvent showed better general properties, including under the exposure to mammographic X-ray energy range that led to sensibility of about 25 μC/Rcm{sup 2}.

  10. Detailed kinetic modeling and sensitivity analysis of hydrogen iodide decomposition in sulfur-iodine cycle for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yanwei; Zhou, Junhu; Wang, Zhihua; Cen, Kefa [State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027 (China)

    2008-01-15

    A new detailed kinetic modeling was developed for homogeneous decomposition of hydrogen iodide (HI) in the sulfur-iodine cycle. Results show the HI decomposition reaction is sensitive to temperature, and the response time of reaction reduces from 1 s to 10 ms as temperature increases from 500 to 800 {sup circle} C. The decomposition is also improved as pressure increased. Kinetic calculations are also compared with the experimental data, and all trends of the experiment can be reproduced by the model. Sensitivity analysis shows that the reactions of HI with HI, H and I play a major role in the hydrogen production process and the hydrogen consumption occurs primarily by reaction of H with I{sub 2} and reaction of I with H{sub 2} to form HI. As temperature increases, different reactions play a dominant role in HI decomposition process. Based on the detailed kinetic modeling and sensitivity analysis results, the HI decomposition reaction path diagram was constructed in this paper. (author)

  11. 1-{2-[4-(4-Nitrophenylpiperazin-1-yl]ethyl}-4-aza-1-azoniabicyclo[2.2.2]octane iodide

    Directory of Open Access Journals (Sweden)

    Anssi Peuronen

    2012-07-01

    Full Text Available The title compound, C18H28N5O2+·I−, was observed as a main product in an intended 1:1 reaction between 4-iodonitrobenzene and 1,4-diazabicyclo[2.2.2]octane (DABCO. In the reaction, DABCO undergoes a ring opening to yield a quaternary salt of DABCO and 1-ethyl-4-(4-nitrophenylpiperazine with an iodide anion. The crystal structure determination was carried out as no crystal structure had been previously reported in the investigations describing the corresponding reaction with 4-chloronitrobenze. Indeed, the crystal structure of the title compound confirms the molecular composition proposed earlier for the analogous chloride salt. The cation conformation is similar to the previously reported dinitro analogue 1-{2-[4-(2,4-dinitrophenylpiperazin-1-yl]ethyl}-4-aza-1-azoniabicyclo[2.2.2]octane chloride [Clegg et al. (2004. Acta Cryst. E60, o291–o293]. The crystal packing is dominated by cation...I− interactions in addition to weak intermolecular C—H...O2N and C—H...N interactions between the cations.

  12. Exceptionally High Payload of the IR780 Iodide on Folic Acid-Functionalized Graphene Quantum Dots for Targeted Photothermal Therapy.

    Science.gov (United States)

    Li, Shuhua; Zhou, Shixin; Li, Yunchao; Li, Xiaohong; Zhu, Jia; Fan, Louzhen; Yang, Shihe

    2017-07-12

    The IR780 iodide (IR780) is recognized as an effective theranostic agent for simultaneous near-infrared fluorescence imaging and photothermal therapy (PTT). However, the rigid chloro-cyclohexenyl ring makes IR780 insoluble in almost all pharmaceutically acceptable solvents, which inevitably limits its clinical application. We report folic acid (FA)-functionalized graphene quantum dots (GQDs-FA) containing a large and intact sp2 domain with carboxyl groups around the edge. Such GQDs-FA possess exceptionally high loading capacity for IR780 via strong π-π stacking interactions, and the water solubility of IR780 is improved by over 2400-fold after loading onto GQDs-FA (IR780/GQDs-FA). IR780/GQDs-FA with an improved photostability, an enhanced tumor-targeting ability, and a high photothermal conversion efficiency of 87.9% were capable of producing sufficient hyperthermia to effectively kill cancer cells and completely eradicate tumors upon 808 nm laser irradiation. The present IR780/GQDs-FA may open up great opportunities for the effective PTT to treat cancer.

  13. Growth and characterization of pure and potassium iodide-doped zinc tris-thiourea sulphate (ZTS) single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, C. [Department of Physics, Arignar Anna College, Aralvoymoli 629301, Tamil Nadu (India)], E-mail: ckrishnan_phy@yahoo.co.in; Selvarajan, P. [Department of Physics, Aditanar College of Arts and Science, Tiruchendur 628216, Tamil Nadu (India); Freeda, T.H.; Mahadevan, C.K. [Physics Research Centre, S.T. Hindu College, Nagercoil 629003, Tamil Nadu (India)

    2009-02-28

    Single crystals of pure and potassium iodide (KI)-doped zinc tris-thiourea sulphate (ZTS) were grown from aqueous solutions by the slow evaporation method. The grown crystals were transparent. The lattice parameters of the grown crystals were determined by the single-crystal X-ray diffraction technique. The grown crystals were also characterized by recording the powder X-ray diffraction pattern and by identifying the diffracting planes. The FT-IR spectrum was recorded in the range 400-4500 cm{sup -1}. Second harmonic generation (SHG) was confirmed by the Kurtz powder method. The thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) studies reveal that the materials have good thermal stability. Atomic absorption studies confirm the presence of dopant in ZTS crystals. The electrical measurements were made in the frequency range 10{sup 2}-10{sup 6} Hz and in the temperature range 40-130 deg. C along a-, b- and c-directions of the grown crystals. The present study shows that the electrical parameters viz. dc conductivity, dielectric constant, dielectric loss factor and ac conductivity increase with increase in temperature. Activation energy values were also determined for the ac conduction process in grown crystals. The dc conductivity, dielectric constant, dielectric loss factor and ac conductivity of KI-doped ZTS crystal were found to be more than those of pure ZTS crystals.

  14. Comments on "Synthesis aspects, structural, spectroscopic, antimicrobial and room temperature ferromagnetism of zinc iodide complex with Schiff based ligand" by K. Shakila and S. Kalainathan, Spectrochim. Acta 135 A (2015) 1059-1065.

    Science.gov (United States)

    Srinivasan, Bikshandarkoil R; Nadkarni, V S

    2016-06-15

    Shakila and Kalainathan report on the synthetic and structural aspects of a zinc iodide complex with Schiff based ligand, which exhibits room temperature ferromagnetism. In this comment, many points of criticism, concerning the characterization of this so called zinc iodide complex of Schiff based ligand are highlighted to prove that the title paper is completely erroneous. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Conversion of Aryl Iodides into Aryliodine(III Dichlorides by an Oxidative Halogenation Strategy Using 30% Aqueous Hydrogen Peroxide in Fluorinated Alcohol

    Directory of Open Access Journals (Sweden)

    Ajda Podgoršek

    2010-04-01

    Full Text Available Oxidative chlorination with HCl/H2O2 in 1,1,1-trifluoroethanol was used to transform aryl iodides into aryliodine(III dihalides. In this instance 1,1,1-trifluoroethanol is not only the reaction medium, but is also an activator of hydrogen peroxide for the oxidation of hydrochloric acid to molecular chlorine. Aryliodine(III dichlorides were formed in 72–91% isolated yields in the reaction of aryl iodides with 30% aqueous hydrogen peroxide and hydrochloric acid at ambient temperature. A study of the effect that substituents on the aromatic ring have on the formation and stability of aryliodine(III dichlorides shows that the transformation is easier to achieve in the presence of the electron-donating groups (i.e. methoxy, but in this case the products rapidly decompose under the reported reaction conditions to form chlorinated arenes. The results suggest that oxidation of hydrogen chloride with hydrogen peroxide is the initial reaction step, while direct oxidation of aryl iodide with hydrogen peroxide is less likely to occur.

  16. The Effect of Lithium Iodide to the Properties of Carboxymethyl κ-Carrageenan/Carboxymethyl Cellulose Polymer Electrolyte and Dye-Sensitized Solar Cell Performance

    Directory of Open Access Journals (Sweden)

    Siti Rudhziah Che Balian

    2016-05-01

    Full Text Available This study was undertaken to investigate the solid biopolymer electrolytes based on a carboxymethyl κ-carrageenan/carboxymethyl cellulose blend complexed with lithium iodide of various weight ratios. The complexation of the doping salt with the polymer blend was confirmed by Fourier transform infrared spectroscopy. Ionic conductivity of the film was determined by impedance spectroscopy in the frequency range of 10 Hz to 4 MHz and in the temperature range of 303–338 K. The ionic conductivity increased with the increase in lithium iodide concentration as well as temperature. The membrane comprising 30 wt % of lithium iodide was found to give the highest conductivity of 3.89 × 10−3 S·cm−1 at room temperature. The increase in conductivity was associated with the increase in the number as well as the mobility of the charge carries. The conductivity increase with temperature followed the Vogel–Tamman–Fulcher model. The fabricated dye-sensitive solar cell, FTO/TiO2-dye/CMKC/CMCE-LiI (30 wt % +I2/Pt exhibited the highest conversion efficiency of 0.11% at a light intensity of 100 mW·cm−2. This indicated that the biopolymer blend electrolyte system has potential for use in dye-sensitized solar cells.

  17. Sulfide iodides (MSI) of the heavier lanthanoids (M = Gd - Lu). Crystal structures and magnetic properties; Sulfidiodide (MSI) der schweren Lanthanoide (M = Gd - Lu). Kristallstrukturen und magnetische Eigenschaften

    Energy Technology Data Exchange (ETDEWEB)

    Blaschkowski, Bjoern; Schleid, Thomas [Institut fuer Anorganische Chemie, Universitaet Stuttgart (Germany); Rosner, Helge; Schnelle, Walter [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Dresden (Germany)

    2013-02-15

    From reactions of equimolar quantities of the heavier lanthanoids (M = Gd - Lu) with the elements sulfur and iodine in fused silica ampoules (900 C, 10 d) phase-pure samples of the lanthanoid sulfide iodides MSI (M = Gd - Lu) could be prepared. Besides the already structurally determined sulfide iodides MSI with M = Gd and Dy, all samples could be characterized by means of X-ray powder diffraction and their magnetic behavior was examined. In addition a single-crystal structure refinement for HoSI was carried out (orthorhombic, Pmmn; a = 415.09(4) pm, b = 531.34(5) pm, c = 920.53(9) pm), which confirmed the isotypy of the later lanthanoid sulfide iodides with the structure of FeOCl. On the basis of the X-ray powder diffraction experiments all prepared compounds could be indexed in a primitive orthorhombic unit cell. An analysis of the determined lattice parameters and cell volumes resulted in the typical lanthanoid contraction for compounds within the row of the 4f elements. The magnetochemical studies led to the expected effective magnetic moments for trivalent lanthanoid cations without showing any magnetic ordering phenomenon. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Evaluation of Lentiviral-Mediated Expression of Sodium Iodide Symporter in Anaplastic Thyroid Cancer and the Efficacy of In Vivo Imaging and Therapy

    Directory of Open Access Journals (Sweden)

    Chien-Chih Ke

    2011-01-01

    Full Text Available Anaplastic thyroid carcinoma (ATC is one of the most deadly cancers. With intensive multimodalities of treatment, the survival remains low. ATC is not sensitive to 131I therapy due to loss of sodium iodide symporter (NIS gene expression. We have previously generated a stable human NIS-expressing ATC cell line, ARO, and the ability of iodide accumulation was restored. To make NIS-mediated gene therapy more applicable, this study aimed to establish a lentiviral system for transferring hNIS gene to cells and to evaluate the efficacy of in vitro and in vivo radioiodide accumulation for imaging and therapy. Lentivirus containing hNIS cDNA were produced to transduce ARO cells which do not concentrate iodide. Gene expression, cell function, radioiodide imaging and treatment were evaluated in vitro and in vivo. Results showed that the transduced cells were restored to express hNIS and accumulated higher amount of radioiodide than parental cells. Therapeutic dose of 131I effectively inhibited the tumor growth derived from transduced cells as compared to saline-treated mice. Our results suggest that the lentiviral system efficiently transferred and expressed hNIS gene in ATC cells. The transduced cells showed a promising result of tumor imaging and therapy.

  19. Highly efficient solid-state dye-sensitized solar cells based on hexylimidazolium iodide ionic polymer electrolyte prepared by in situ low-temperature polymerization

    Science.gov (United States)

    Wang, Guiqiang; Yan, Chao; Zhang, Juan; Hou, Shuo; Zhang, Wei

    2017-03-01

    Solid-state dye-sensitized solar cells (DSCs) are fabricated using a novel ionic polymer electrolyte containing hexylimidazolium iodide (HII) ionic polymer prepared by in situ polymerization of N,N‧-bis(imidazolyl) hexane and 1,6-diiodohexane without an initiator at low temperature (40 °C). The as-prepared HII ionic polymer has a similar structure to alkylimidazolium iodide ionic liquid, and the imidazolium cations are contained in the polymer main chain; so, it can act simultaneously as the redox mediator in the electrolyte. By incorporating an appropriate amount of 1,3-dimethylimidazolium iodide (DMII) in HII ionic polymer (DMII/HII ionic polymer = 0.7:1, weight ratio), the conductivity of the ionic polymer electrolyte is greatly improved due to the formation of Grotthuss bond exchange. In addition, in situ synthesis of ionic polymer electrolyte guarantees a good pore-filling of the electrolyte in the TiO2 photoanode. As a result, the solid-state DSC based on the ionic polymer electrolyte containing HII ionic polymer and DMII without iodine achieves a conversion efficiency of 6.55% under the illumination of 100 mW cm-2 (AM 1.5), which also exhibits a good at-rest stability at room temperature.

  20. Effects of iodine and thyroid hormones in inducing and treating Hashimoto's thyroiditis; Effekte von Iodid und Schilddruesenhormonen bei der Induktion und Therapie einer Thyreoiditis Hashimoto

    Energy Technology Data Exchange (ETDEWEB)

    Rink, T.; Schroth, H.J.; Holle, L.H.; Garth, H. [Stadtkrankenhaus Hanau (Germany). Abt. fuer Nuklearmedizin

    1999-07-01

    Aim: The effect of an iodine prophylaxis on the induction of Hashimoto's thyroiditis as well as the influence of various therapeutic approaches on the course of antithyroglobulin (TgAb) and antiperoxidase (TPOAb) antibodies in manifest diseases are evaluated. Method: A collective of 375 euthyroid subjects without relevant goiter received daily doses of 200 micrograms iodide, weekly doses of 1.53 milligrams iodide, or no medication. A second group of 377 patients suffering from Hashimoto's thyroiditis was treated with a non-suppressive hormone medication, a suppressive hormone administration, a combination of a non-suppressive hormone therapy with low dose iodide (50-150 micrograms/day), mere iodide in doses of 200 micrograms/day, or received no therapy. The mean observation period in these two groups was 860 and 848 days, respectively. Results: There was no significant increase of the antibody levels in the subgroup with 200 micrograms iodide/day and in the non-treated subjects of the first collective. However, the group that received 1.53 milligrams iodide/week presented a distinct increase of the TgAb as well as the TPOAb, and the incidence of Hashimoto's thyroiditis was 4-fold higher than in the two other subgroups. The patients of the second collective revealed a sinificant decrease of the TgAb in the subgroups treated with up to 200 micrograms iodide/day, while the reduction of the TPOAb depended on the thyrotropin level and was most significant in the suppressed group (p<0.0001). Conclusion: To lower the incidence of autoimmune thyroid diseases in predisposed subjects, a daily iodine supplementation seems to be superior to high-dose weekly administrations. A hormone therapy combined with a daily, low-dose iodine medication is able to reduce the TgAb and the TPOAb levels even in patients with Hashimoto's thyroidits. (orig.) [German] Ziel: Untersucht wurden der Einfluss einer Iodprophylaxe auf die Inzidenz einer Autoimmunthyreoiditis bzw

  1. Feasibility study of a lead(II) iodide-based dosimeter for quality assurance in therapeutic radiology

    Science.gov (United States)

    Heo, Y. J.; Kim, K. T.; Oh, K. M.; Lee, Y. K.; Ahn, K. J.; Cho, H. L.; Kim, J. Y.; Min, B. I.; Mun, C. W.; Park, S. K.

    2017-09-01

    The most widely used form of radiotherapy to treat tumors uses a linear accelerator, and the apparatus requires regular quality assurance (QA). QA for a linear accelerator demands accuracy throughout, from mock treatment and treatment planning, up to treatment itself. Therefore, verifying a radiation dose is essential to ensure that the radiation is being applied as planned. In current clinical practice, ionization chambers and diodes are used for QA. However, using conventional gaseous ionization chambers presents drawbacks such as complex analytical procedures, difficult measurement procedures, and slow response time. In this study, we discuss the potential of a lead(II) iodide (PbI2)-based radiation dosimeter for radiotherapy QA. PbI2 is a semiconductor material suited to measurements of X-rays and gamma rays, because of its excellent response properties to radiation signals. Our results show that the PbI2-based dosimeter offers outstanding linearity and reproducibility, as well as dose-independent characteristics. In addition, percentage depth dose (PDD) measurements indicate that the error at a fixed reference depth Dmax was 0.3%, very similar to the measurement results obtained using ionization chambers. Based on these results, we confirm that the PbI2-based dosimeter has all the properties required for radiotherapy: stable dose detection, dose linearity, and rapid response time. Based on the evidence of this experimental verification, we believe that the PbI2-based dosimeter could be used commercially in various fields for precise measurements of radiation doses in the human body and for measuring the dose required for stereotactic radiosurgery or localized radiosurgery.

  2. Treatment of medulloblastoma using an oncolytic measles virus encoding the thyroidal sodium iodide symporter shows enhanced efficacy with radioiodine

    Directory of Open Access Journals (Sweden)

    Hutzen Brian

    2012-11-01

    Full Text Available Abstract Background Medulloblastoma is the most common malignant brain tumor of childhood. Although the clinical outcome for medulloblastoma patients has improved significantly, children afflicted with the disease frequently suffer from debilitating side effects related to the aggressive nature of currently available therapy. Alternative means for treating medulloblastoma are desperately needed. We have previously shown that oncolytic measles virus (MV can selectively target and destroy medulloblastoma tumor cells in localized and disseminated models of the disease. MV-NIS, an oncolytic measles virus that encodes the human thyroidal sodium iodide symporter (NIS, has the potential to deliver targeted radiotherapy to the tumor site and promote a localized bystander effect above and beyond that achieved by MV alone. Methods We evaluated the efficacy of MV-NIS against medulloblastoma cells in vitro and examined their ability to incorporate radioiodine at various timepoints, finding peak uptake at 48 hours post infection. The effects of MV-NIS were also evaluated in mouse xenograft models of localized and disseminated medulloblastoma. Athymic nude mice were injected with D283med-Luc medulloblastoma cells in the caudate putamen (localized disease or right lateral ventricle (disseminated disease and subsequently treated with MV-NIS. Subsets of these mice were given a dose of 131I at 24, 48 or 72 hours later. Results MV-NIS treatment, both by itself and in combination with 131I, elicited tumor stabilization and regression in the treated mice and significantly extended their survival times. Mice given 131I were found to concentrate radioiodine at the site of their tumor implantations. In addition, mice with localized tumors that were given 131I either 24 or 48 hours after MV-NIS treatment exhibited a significant survival advantage over mice given MV-NIS alone. Conclusions These data suggest MV-NIS plus radioiodine may be a potentially useful therapy for

  3. In situ investigation of the formation and metastability of formamidinium lead tri-iodide perovskite solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Jeffery A.; Wozny, Sarah; Holesinger, Terry G.; Aoki, Toshihiro; Patel, Maulik K.; Yang, Mengjin; Berry, Joseph J.; Al-Jassim, Mowafak; Zhou, Weilie; Zhu, Kai

    2016-01-01

    Organic-inorganic perovskites have emerged as an important class of next generation solar cells due to their remarkably low cost, band gap, and sub-900 nm absorption onset. Here, we show a series of in situ observations inside electron microscopes and X-ray diffractometers under device-relevant synthesis conditions focused on revealing the crystallization process of the formamidinium lead-triiodide perovskite at the optimum temperature of 175 degrees C. Direct in situ observations of the structure and chemistry over relevant spatial, temporal, and temperature scales enabled identification of key perovskite formation and degradation mechanisms related to grain evolution and interface chemistry. The lead composition was observed to fluctuate at grain boundaries, indicating a mobile lead-containing species, a process found to be partially reversible at a key temperature of 175 degrees C. Using low energy electron microscopy and valence electron energy loss spectroscopy, lead is found to be bonded in the grain interior with iodine in a tetrahedral configuration. At the grain boundaries, the binding energy associated with lead is consequently shifted by nearly 2 eV and a doublet peak is resolved due presumably to a greater degree of hybridization and the potential for several different bonding configurations. At the grain boundaries there is adsorption of hydrogen and OH- ions as a result of residual water vapor trapped as a non-crystalline material during formation. Insights into the relevant formation and decomposition reactions of formamidinium lead iodide at low to high temperatures, observed metastabilities, and relationship with the photovoltaic performance were obtained and used to optimize device processing resulting in conversion efficiencies of up to 17.09% within the stability period of the devices.

  4. Cyclic AMP-response element modulator inhibits the promoter activity of the sodium iodide symporter gene in thyroid cancer cells.

    Science.gov (United States)

    Passon, Nadia; Puppin, Cinzia; Lavarone, Elisa; Bregant, Elisa; Franzoni, Alessandra; Hershman, Jerome M; Fenton, Mike S; D'Agostino, Maria; Durante, Cosimo; Russo, Diego; Filetti, Sebastiano; Damante, Giuseppe

    2012-05-01

    Comprehension of the regulatory mechanism involved in the sodium iodide symporter (NIS) expression is of great relevance for thyroid cancer. In fact, restoration of NIS expression would be a strategy to treat undifferentiated thyroid cancer. Previous in vitro findings suggest that the cyclic AMP-response element (CRE) modulator (CREM) is involved in control of NIS expression. In this work, we examined the expression of CREM in a series of thyroid cancer tissues and its action on NIS promoter in human thyroid cancer cells. Expression of mRNA levels for CREM, PAX8 and NIS was measured by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) in 6 normal thyroid tissues, 22 papillary, 12 follicular and 4 anaplastic thyroid cancers. The effect of CREM on transcriptional activity of the NIS promoter was investigated by transient transfection of human thyroid cell lines. Compared to normal tissues, NIS and PAX8 mRNA levels were significantly reduced in all types of thyroid cancer. As expected, the maximal decrease was detected in anaplastic thyroid cancer. Conversely, CREM mRNA levels were increased in all types of thyroid cancer, reaching statistical significance for follicular and anaplastic thyroid carcinoma (p=0.0157 and 0.0045, respectively). Transfection experiments showed an inhibitory effect of CREM on NIS promoter activity in various thyroid cancer cell lines. These data demonstrate that CREM expression is increased in thyroid cancer tissue and may play a role in the downregulation of NIS expression in thyroid cancer acting at the transcriptional level.

  5. Effect of Rubidium Incorporation on the Structural, Electrical, and Photovoltaic Properties of Methylammonium Lead Iodide-Based Perovskite Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ik Jae [Department of Materials; Seo, Seongrok [Department of Energy; Park, Min Ah [Department of Materials; Lee, Sangwook [School of Materials Science and Engineering, Kyungpook National University, Daegu 41566, South Korea; Kim, Dong Hoe [Chemistry and Nanoscience Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States; Zhu, Kai [Chemistry and Nanoscience Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States; Shin, Hyunjung [Department of Energy; Kim, Jin Young [Department of Materials

    2017-11-17

    We report the electrical properties of rubidium-incorporated methylammonium lead iodide ((RbxMA1-x)PbI3) films and the photovoltaic performance of (RbxMA1-x)PbI3 film-based p-i-n-type perovskite solar cells (PSCs). The incorporation of a small amount of Rb+ (x = 0.05) increases both the open circuit voltage (Voc) and the short circuit photocurrent density (Jsc) of the PSCs, leading to an improved power conversion efficiency (PCE). However, a high fraction of Rb+ incorporation (x = 0.1 and 0.2) decreases the Jsc and thus the PCE, which is attributed to the phase segregation of the single tetragonal perovskite phase to a MA-rich tetragonal perovskite phase and a RbPbI3 orthorhombic phase at high Rb fractions. Conductive atomic force microscopic and admittance spectroscopic analyses reveal that the single-phase (Rb0.05MA0.95)PbI3 film has a high electrical conductivity because of a reduced deep-level trap density. We also found that Rb substitution enhances the diode characteristics of the PSC, as evidenced by the reduced reverse saturation current (J0). The optimized (RbxMA1-x)PbI3 PSCs exhibited a PCE of 18.8% with negligible hysteresis in the photocurrent-voltage curve. The results from this work enhance the understanding of the effect of Rb incorporation into organic-inorganic hybrid halide perovskites and enable the exploration of Rb-incorporated mixed perovskites for various applications, such as solar cells, photodetectors, and light-emitting diodes.

  6. Highly efficient organic solar Cells based on a robust room-temperature solution-processed copper iodide hole transporter

    KAUST Repository

    Zhao, Kui

    2015-07-30

    Achieving high performance and reliable organic solar cells hinges on the development of stable and energetically suitable hole transporting buffer layers in tune with the electrode and photoactive materials of the solar cell stack. Here we have identified solution-processed copper(I) iodide (CuI) thin films with low-temperature processing conditions as an effective hole–transporting layer (HTL) for a wide range of polymer:fullerene bulk heterojunction (BHJ) systems. The solar cells using CuI HTL show higher power conversion efficiency (PCE) in standard device structure for polymer blends, up to PCE of 8.8%, as compared with poly(3,4-ethylenedioxy-thiophene):poly(styrenesulfonate) (PEDOT:PSS) HTL, for a broad range of polymer:fullerene systems. The CuI layer properties and solar cell device behavior are shown to be remarkably robust and insensitive to a wide range of processing conditions of the HTL, including processing solvent, annealing temperature (room temperature up to 200 °C), and film thickness. CuI is also shown to improve the overall lifetime of solar cells in the standard architecture as compared to PEDOT:PSS. We further demonstrate promising solar cell performance when using CuI as top HTL in an inverted device architecture. The observation of uncommon properties, such as photoconductivity of CuI and templating effects on the BHJ layer formation, are also discussed. This study points to CuI as being a good candidate to replace PEDOT:PSS in solution-processed solar cells thanks to the facile implementation and demonstrated robustness of CuI thin films.

  7. Predictive role of nontumoral sodium iodide symporter activity and preoperative thyroid characteristics in remission process of thyroid cancer patients.

    Science.gov (United States)

    Yildirim-Poyraz, Nilufer; Yazgan, Aylin; Ozdemir, Elif; Gozalan, Aysegul; Keskin, Mutlay; Ersoy, Reyhan; Turkolmez, Seyda; Cakir, Bekir

    2014-08-01

    The target of radioiodine ablation therapy (RIAT) after complete tumor removal is the nontumoral remnant tissue. We aimed to evaluate sodium iodide symporter (NIS) expression in nontumoral thyroid tissue in differentiated thyroid cancer (DTC) patients who have complete but delayed structural response (DSR) to RIAT after surgery. Preoperative thyroid characteristics such as volume and nontumoral histology were also investigated for both DSR and its control group as potential predictors of insufficient NIS activity in this study. Total of 600 patients with postoperative remnant thyroid tissue and who were in remission after RIAT spontaneously, were included in the study. Patients with positive diagnostic whole body scan (DxWBS) with thyroid bed uptake and stimulated serum Tg level thyroid characteristics. When compared with the control group, the density and intensity of NIS expression as well as the intensity of RAI uptake were significantly lower in DSR group (p = 0.001). There were also significant differences between groups regarding preoperative thyroid characteristics; i.e. preoperative thyroid volumes were significantly higher and the presence of concurrent benign thyroid disease was significantly more common in DSR group (p = 0.035, p = 0.001). Hashimoto thyroiditis was 8.59 times higher (95% CI; 2.31-31.96) and multinodular goiter was 7.50 times higher (95% CI; 1.88-29.91) among DSR group when compared with the control group. Our findings suggest that insufficient NIS activity in nontumoral thyroid tissue associates with DSR in DTC patients who have postoperative remnant tissue. Preoperative thyroid characteristics such as volume and concomitant benign thyroid disease may have an important role in predicting the complete response time to RIAT in these patients.

  8. Chemical behavior of radioiodine in soils, (1). Studies on the sorption and desorption of iodide on sandy soils

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Shigeo; Kamada, Hiroshi (National Inst. of Radiological Sciences, Nakaminato, Ibaraki (Japan). Nakaminato Lab. Branch Office)

    1983-12-01

    Iodine-129 will be accumulated in the environment owing to its long half-life. In order to estimate its impact on man, it is necessary to obtain the information about its accumulation and movement in the environment over the long period. In this paper, the sorption and desorption of iodide (I/sup -/) on sandy soils were examined by using column and batch experiments. The results obtained were as follows: 1) Every breakthrough curves of I/sup -/ showed plateau, before the ratio of concentration (C/C/sub 0/) were reached 1.0. The ratio C/C/sub 0/ on plateau in the effluent was affected by the kind of soil and NaI concentration in the inflow solution. 2) Iodine once sorbed on soil would be scarcely removed with 5.0 x 10/sup -4/ mol/l CaCl/sub 2/ solution. 3) Chemical form of iodine in the effluent was identified, showing that, more than 90% was recovered as I/sup -/. 4) In batch experiment, the equilibrium period on the sorption of I/sup -/ by anion exchange resin and soil was examined. The equilibrum period on the sorption by anion exchange resin was within 3 hr, but the period by soil was more than 15 days. This means that the sorption phenomenon of I/sup -/ to soil is not always based on an ion exchange reaction on the surface of soil particle. 5) A new theory should be examined for evaluating the movement of I/sup -/ in a soil.

  9. Determination of major sodium iodide symporter (NIS) inhibitors in drinking waters using ion chromatography with conductivity detector.

    Science.gov (United States)

    Cengiz, Mehmet Fatih; Bilgin, Ayse Kevser

    2016-02-20

    Goiter is an important health problem all over the world and iodine deficiency is its most common cause. Perchlorate, thiocyanate and nitrate (called as major NIS inhibitors) are known to competitively inhibit iodide uptake by the thyroid gland and thus, human exposure to major NIS inhibitors is a public health concern. In this study, an ion chromatographic method for the determination of most common NIS inhibitor ions in drinking waters was developed and validated. This is the first study where an analytical method is used for the determination of major NIS inhibitors in drinking water by an ion chromatography system in a single run. Chromatographic separations were achieved with an anion-exchange column and separated ions were identified by a conductivity detector. The method was found to be selective, linear, precise accurate and true for all of interested ions. The limits of the detections (LOD) were estimated at 0.003, 0.004 and 0.025mgL(-1) for perchlorate, thiocyanate and nitrate, respectively. Possible interference ions in drinking waters were examined for the best separation of NIS inhibitors. The excellent method validation data and proficiency test result (Z-score for nitrate: -0.1) of the FAPAS(®) suggested that the developed method could be applied for determination of NIS inhibitor residues in drinking waters. To evaluate the usefulness of the method, 75 drinking water samples from Antalya/Turkey were analyzed for NIS inhibitors. Perchlorate concentrations in the samples ranged from not detected (less than LOD) to 0.07±0.02mgL(-1) and the range of nitrate concentrations were found to be 3.60±0.01mgL(-1) and 47.42±0.40mgL(-1). No thiocyanate residues were detected in tested drinking water samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Exploration of strategies for implementation of screen-printed mercuric iodide converters in direct detection AMFPIs for digital breast tomosynthesis

    Science.gov (United States)

    Antonuk, Larry E.; El-Mohri, Youcef; Zhao, Qihua; Jiang, Hao

    2017-03-01

    Digital breast tomosynthesis (DBT) has become an increasingly important tool in the diagnosis of breast disease. For those DBT imaging systems based on active matrix, flat-panel imager (AMFPI) arrays, the incident radiation is detected directly or indirectly by means of an a-Se or CsI:Tl x-ray converter, respectively. While all AMFPI DBT devices provide clinically useful volumetric information, their performance is limited by the relatively modest average signal generated per interacting X ray by present converters compared to the electronic additive noise of the system. To address this constraint, we are pursuing the development of a screen-printed form of mercuric iodide (SP HgI2) which has demonstrated considerably higher sensitivities (i.e., larger average signal per interacting X ray) than those of conventional a-Se and CsI:Tl converters, as well as impressive DQE and MTF performance under mammographic irradiation conditions. A converter offering such enhanced sensitivity would greatly improve signal-to-noise performance and facilitate quantum-limited imaging down to significantly lower exposures than present AMFPI DBT systems. However, before this novel converter material can be implemented practically, challenges associated with SP HgI2 must be addressed. Most significantly, high levels of charge trapping (which lead to image lag as well as fall-off in DQE at higher exposures) need to be reduced - while improving the uniformity in pixel-to-pixel signal response as well as maintaining low dark current and otherwise favorable DQE performance. In this paper, a pair of novel strategies for overcoming the challenge of charge trapping in SP HgI2 converters are described, and initial results from empirical and calculational studies of these strategies are reported.

  11. A europium- and terbium-coated magnetic nanocomposite as sorbent in dispersive solid phase extraction coupled with ultra-high performance liquid chromatography for antibiotic determination in meat samples.

    Science.gov (United States)

    Castillo-García, M L; Aguilar-Caballos, M P; Gómez-Hens, A

    2015-12-18

    A new magnetic dispersive solid-phase extraction approach based on Eu- and Tb-coated magnetic nanocomposites, combined with ultra-high performance liquid chromatography with fluorometric detection, is reported for the extraction and simultaneous determination of veterinary antibiotics. The method is aimed at monitoring of potential residues of three tetracyclines, namely oxytetracycline, tetracycline, chlortetracycline and three acidic quinolones, such as oxolinic acid, nalidixic acid and flumequine, chosen as model analytes, in animal muscle samples. The nanocomposites were obtained by synthesizing magnetic nanoparticles by a co-precipitation method and their coating with terbium and europium ions. The limits of detection obtained using standard solutions were: 1.0, 1.5, 3.8, 0.25, 0.7 and 1.2ngmL(-1), which corresponds to 3.3, 5.0, 12.7, 0.8, 2.3 and 4.0μgkg(-1) for oxytetracycline, tetracycline, chlortetracycline, oxolinic acid, nalidixic acid and flumequine, respectively, in meat samples. The precision values, obtained in the presence of the sample matrix, were in the ranges 0.12-2.0% and 2.6-15.4% for retention times and areas, respectively. The selectivity of the method was checked by assaying different veterinary drugs, finding that most of them did not interfere at the same concentration levels as that of analytes. A recovery study was performed in the presence of chicken and pork muscle samples, which provided values in the range of 61.5-102.6%. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Sequence-defined cMET/HGFR-targeted Polymers as Gene Delivery Vehicles for the Theranostic Sodium Iodide Symporter (NIS) Gene.

    Science.gov (United States)

    Urnauer, Sarah; Morys, Stephan; Krhac Levacic, Ana; Müller, Andrea M; Schug, Christina; Schmohl, Kathrin A; Schwenk, Nathalie; Zach, Christian; Carlsen, Janette; Bartenstein, Peter; Wagner, Ernst; Spitzweg, Christine

    2016-08-01

    The sodium iodide symporter (NIS) as well-characterized theranostic gene represents an outstanding tool to target different cancer types allowing noninvasive imaging of functional NIS expression and therapeutic radioiodide application. Based on its overexpression on the surface of most cancer types, the cMET/hepatocyte growth factor receptor serves as ideal target for tumor-selective gene delivery. Sequence-defined polymers as nonviral gene delivery vehicles comprising polyethylene glycol (PEG) and cationic (oligoethanoamino) amide cores coupled with a cMET-binding peptide (cMBP2) were complexed with NIS-DNA and tested for receptor-specificity, transduction efficiency, and therapeutic efficacy in hepatocellular cancer cells HuH7. In vitro iodide uptake studies demonstrated high transduction efficiency and cMET-specificity of NIS-encoding polyplexes (cMBP2-PEG-Stp/NIS) compared to polyplexes without targeting ligand (Ala-PEG-Stp/NIS) and without coding DNA (cMBP2-PEG-Stp/Antisense-NIS). Tumor recruitment and vector biodistribution were investigated in vivo in a subcutaneous xenograft mouse model showing high tumor-selective iodide accumulation in cMBP2-PEG-Stp/NIS-treated mice (6.6 ± 1.6% ID/g (123)I, biological half-life 3 hours) by (123)I-scintigraphy. Therapy studies with three cycles of polyplexes and (131)I application resulted in significant delay in tumor growth and prolonged survival. These data demonstrate the enormous potential of cMET-targeted sequence-defined polymers combined with the unique theranostic function of NIS allowing for optimized transfection efficiency while eliminating toxicity.

  13. {sup 99m}Tc-pertechnetate uptake in hepatoma cells due to tissue-specific human sodium iodide symporter gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Chen Libo [Department of Nuclear Medicine, Shanghai Sixth People' s Hospital, Shanghai Jiao Tong University, 200233 Shanghai (China); Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Center (DKFZ) and Heidelberg University, 69120 Heidelberg (Germany); Altman, Annette [Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Center (DKFZ) and Heidelberg University, 69120 Heidelberg (Germany); Mier, Walter [Department of Nuclear Medicine, University of Heidelberg, 69120 Heidelberg (Germany); Lu Hankui [Department of Nuclear Medicine, Shanghai Sixth People' s Hospital, Shanghai Jiao Tong University, 200233 Shanghai (China); Zhu Ruisen [Department of Nuclear Medicine, Shanghai Sixth People' s Hospital, Shanghai Jiao Tong University, 200233 Shanghai (China); Haberkorn, Uwe [Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Center (DKFZ) and Heidelberg University, 69120 Heidelberg (Germany) and Department of Nuclear Medicine, University of Heidelberg, 69120 Heidelberg (Germany)]. E-mail: uwe_haberkorn@med.uni-heidelberg.de

    2006-05-15

    The sodium iodide symporter (NIS) gene could be used as an ideal reporter gene as well as a promising therapeutic gene. {sup 99m}Tc-pertechnetate has proven to be more advantageous than {sup 131}I-iodide with respect to image quality, procedure and radiation dose in examination of thyroid uptake and scintigraphy. Herein, we investigated the feasibility of monitoring human sodium iodide symporter (hNIS) gene expression with {sup 99m}Tc-pertechnetate in hepatoma cells (MH3924A) following tissue-specific expression. Methods: MH3924A cells were stably transfected with the recombinant retroviral vector, in which hNIS cDNA was driven by murine albumin enhancer/promoter (mAlb) and coupled to hygromycin resistance gene using an internal ribosomal entry site. Functional NIS expression in hepatoma cells was confirmed by an {sup 125}I{sup -} uptake assay. The dynamic uptake and efflux of {sup 99m}Tc-pertechnetate was determined both in vitro and in vivo. Results: The {sup 99m}Tc-pertechnetate was up to 254-fold higher in stably transfected MH3924A cells than in wild-type cells. However, the in vitro efflux of {sup 99m}Tc-pertechnetate out of recombinant cells was rapid with a half-life of less than 2 min. Further, the in vivo studies yielded clear images and quantitative data of mAlbhNIS-infected tumor xenografts using {sup 99m}Tc-pertechnetate and {gamma} camera. Conclusion: The current study demonstrates enhanced {sup 99m}Tc-pertechnetate uptake in hepatoma cells in vitro and in vivo following tissue-specific gene transfer using a recombinant retrovirus with the albumin enhancer/promoter and the hNIS gene. It is feasible to monitor hNIS gene expression noninvasively and quantitatively using conventional {gamma} camera and {sup 99m}Tc-pertechnetate.

  14. Total iodine quantification in fluids and tissues from iodine- or iodide-supplemented rats by ion chromatography following microwave-assisted digestion.

    Science.gov (United States)

    Delgado, Guadalupe; Muñoz-Torres, Carolina; Orozco-Esquivel, Teresa; Anguiano, Brenda; Aceves, Carmen

    2015-03-01

    Iodine is a crucial component of thyroid hormones, and several reports have shown that iodine per se is implicated in the physiopathology of other organs. Innovative ion chromatography detection following a four-step temperature ramp microwave digestion in 25-50 mM nitric acid was developed to measure total iodine in biological fluids and tissue samples from female Sprague-Dawley rats supplemented with 0.05% molecular iodine (I2) or 0.05% potassium iodide (I(-)) in drinking water. The reported method allows the measurement of total iodine with a limit of quantification of 13.7 μg L(-1), recoveries of 96.3-100.3%, and intra- and inter-assay variations, of 3.5% and 7.4% respectively. Analysis of biological fluids showed that after 48 hours, iodine-supplemented animals exhibited significantly higher levels of total iodine in both serum and urine compared with those supplemented with iodide. The half-life of iodine in serum and urine measured over the first 48 h showed similar patterns for both the I2 (7.89 and 7.76 hours) and I(-) (8.27 and 8.90 hours) supplements. Differential uptake patterns were observed in tissues after 6 days of supplements, with I(-) preferentially retained by thyroid, lactating mammary gland, and milk, and a slightly but significantly higher capture of I2 in pituitary, ovary, and virgin mammary gland. We developed a rapid, selective, and accurate digestion method to process fluid and tissue samples that permits reproducible measurements of total iodine by ion chromatography; iodine or iodide supplement show a similar serum and urine half-life, but organ-specific uptake depends on the chemical form of the iodine supplement.

  15. Determination of silver, antimony, bismuth, copper, cadmium and indium in ores, concentrates and related materials by atomic-absorption spectrophotometry after methyl isobutyl ketone extraction as iodides.

    Science.gov (United States)

    Donaldson, E M; Wang, M

    1986-03-01

    Methods for determining ~ 0.2 mug g or more of silver and cadmium, ~ 0.5 mug g or more of copper and ~ 5 mug g or more of antimony, bismuth and indium in ores, concentrates and related materials are described. After sample decomposition and recovery of antimony and bismuth retained by lead and calcium sulphates, by co-precipitation with hydrous ferric oxide at pH 6.20 +/- 0.05, iron(III) is reduced to iron(II) with ascorbic acid, and antimony, bismuth, copper, cadmium and indium are separated from the remaining matrix elements by a single methyl isobutyl ketone extraction of their iodides from ~2M sulphuric acid-0.1M potassium iodide. The extract is washed with a sulphuric acid-potassium iodide solution of the same composition to remove residual iron and co-extracted zinc, and the extracted elements are stripped from the extract with 20% v v nitric acid-20% v v hydrogen peroxide. Alternatively, after the removal of lead sulphate by filtration, silver, copper, cadmium and indium can be extracted under the same conditions and stripped with 40% v v nitric acid-25% v v hydrochloric acid. The strip solutions are treated with sulphuric and perchloric acids and ultimately evaporated to dry ness. The individual elements are determined in a 24% v v hydrochloric acid medium containing 1000 mug of potassium per ml by atomic-absorption spectrophotometry with an air-acetylene flame. Tin, arsenic and molybdenum are not co-extracted under the conditions above. Results obtained for silver, antimony, bismuth and indium in some Canadian certified reference materials by these methods are compared with those obtained earlier by previously published methods.

  16. Radiochemotherapy of hepatocarcinoma via lentivirus-mediated transfer of human sodium iodide symporter gene and herpes simplex virus thymidine kinase gene

    Energy Technology Data Exchange (ETDEWEB)

    Chen Libo, E-mail: libochen888@hotmail.com [Department of Nuclear Medicine, Shanghai Sixth People' s Hospital, Shanghai Jiao Tong University, Shanghai 200233 (China); Guo Guoying [Xinyuan Institute of Medicine and Biotechnology, School of Life Sciences, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Liu Tianjing; Guo Lihe [Division of Biochemistry and Cell Biology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Zhu Ruisen [Department of Nuclear Medicine, Shanghai Sixth People' s Hospital, Shanghai Jiao Tong University, Shanghai 200233 (China)

    2011-07-15

    Herpes simplex virus thymidine kinase (HSV-TK) gene/ganciclovir (GCV) system has been widely used as a traditional gene therapy modality, and the sodium/iodide symporter gene (NIS) has been found to be a novel therapeutic gene. Since the therapeutic effects of radioiodine therapy or prodrug chemotherapy on cancers following NIS or HSV-TK gene transfer need to be enhanced, this study was designed to investigate the feasibility of radiochemotherapy for hepatocarcinoma via coexpression of NIS gene and HSV-TK gene. Methods: HepG2 cells were stably transfected with NIS, TK and GFP gene via recombinant lentiviral vector and named HepG2/NTG. Gene expression was examined by reverse transcriptase polymerase chain reaction, fluorescence imaging and iodide uptake. The therapeutic effects were assessed by MTT assay and clonogenic assay. Results: HepG2/NTG cells concentrated {sup 125}I{sup -} up to 76-fold higher than the wild-type cells within 20 min, and the efflux happened with a T{sub 1/2eff} of less than 10 min. The iodide uptake in HepG2/NTG cells was specifically inhibited by sodium perchlorate. Dose-dependent toxicity to HepG2/NTG cells by either GCV or {sup 131}I was revealed by clonogenic assay and MTT assay, respectively. The survival rate of HepG2/NTG cells decreased to 49.7%{+-}2.5%, 43.4%{+-}2.8% and 8.6%{+-}1.2% after exposure to {sup 131}I, GCV and combined therapy, respectively. Conclusion: We demonstrate that radiochemotherapy of hepatocarcinoma via lentiviral-mediated coexpression of NIS gene and HSV-TK gene leads to stronger killing effect than single treatment, and in vivo studies are needed to verify these findings.

  17. Photoinduced triplet-state electron transfer of platinum porphyrin: a one-step direct method for sensing iodide with an unprecedented detection limit

    KAUST Repository

    Masih, Dilshad

    2015-02-05

    Here, we report for the first time a one-step direct method for sensing halides in aqueous solution using phosphorescence quenching of platinum-cationic porphyrin. This method offers an easy, rapid, environmentally friendly, ultra-sensitive (with a previously unattained detection limit of 1 × 10−12 M) and economical method for the determination of iodide. To fully understand the reaction mechanism responsible for the phosphorescence quenching process, we have employed cutting-edge time-resolved laser spectroscopy with broadband capabilities.

  18. Regio- and stereoselective C-2 and C-3 cleavage of 2-(1-aminoalkyl)aziridines with alcohols, carboxylic acids, and sodium iodide.

    Science.gov (United States)

    Concellón, José M; Riego, Estela; Suárez, José Ramón

    2003-11-28

    Ring opening of nonactivated aziridines 1 using several nucleophiles, such as alcohols, carboxylic acids, and sodium iodide, is described. Depending on the nucleophile used, aziridines 1 are cleaved at C-3 or C-2 with total regio- and stereoselectivity, affording chiral 2-alkoxy-1,3-diamines 2 with alcohols, or O-acylated-1-hydroxy-2,3-diamines 6 with carboxylic acids in moderate or high yield. In the case of the aziridines derived from phenylalanine, treatment with NaI afford trans-4-phenylbut-3-en-1,2-diamines 9, generating the alkene with total diastereoselectivity. Mechanisms have been proposed to explain these reactions.

  19. 8a-Methyl-5,6,8,8a,9,10-hexahydro-10,12a-epoxyisoindolo[1,2-a]isoquinolinium iodide

    Directory of Open Access Journals (Sweden)

    Flavien A. A. Toze

    2010-06-01

    Full Text Available The title compound, C17H18NO+·I−, is an adduct resulting from an intramolecular Diels–Alder reaction of methallyl chloride with 3,4-dihydro-1-furylisoquinoline. The cation comprises a fused pentacyclic system containing three five-membered rings (dihydropyrrole, dihydrofuran and tetrahydrofuran and two six-membered rings (tetrahydropyridine and benzene. The five-membered rings have the usual envelope conformations, and the central six-membered tetrahydropyridine ring adopts the unsymmetrical half-boat conformation. In the crystal, cations and iodide anions are bound by weak intermolecular hydrogen-bonding interactions into a three-dimensional framework.

  20. The new C-C bond formation in the reaction of o-amidophenolate indium(III) complex with alkyl iodides.

    Science.gov (United States)

    Piskunov, Alexandr V; Meshcheryakova, Irina N; Fukin, Georgy K; Shavyrin, Andrei S; Cherkasov, Vladimir K; Abakumov, Gleb A

    2013-08-07

    The reaction of bis(4,6-di-tert-butyl-N-(2,6-di-iso-propylphenyl)-o-amidophenolato)indium(III) anion with alkyl iodides is reported. This process includes oxidative addition of two RI (R = Me, Et) molecules to the non-transition metal complex and results in an alkyl transfer to ring carbon atoms with the formation of two new C-C bonds. The interaction proceeds at mild conditions and gives new indium(III) derivatives containing iminocyclohexa-1,4-dienolate type ligands.

  1. Variable temperature and high-pressure crystal chemistry of perovskite formamidinium lead iodide: a single crystal X-ray diffraction and computational study.

    Science.gov (United States)

    Sun, Shijing; Deng, Zeyu; Wu, Yue; Wei, Fengxia; Halis Isikgor, Furkan; Brivio, Federico; Gaultois, Michael W; Ouyang, Jianyong; Bristowe, Paul D; Cheetham, Anthony K; Kieslich, Gregor

    2017-07-04

    We investigate the variable temperature (100-450 K) and high-pressure (p = ambient - 0.74 GPa) crystal chemistry of the black perovskite formamidinium lead iodide, [(NH2)2CH]PbI3, using single crystal X-ray diffraction. In both cases we find a phase transition to a tetragonal phase. Our experimental results are combined with first principles calculations, providing information about the electronic properties of [(NH2)2CH]PbI3 as well as the most probable orientation of the [(NH2)2CH](+) cations.

  2. Imaging characteristics, tissue distribution, and spread of a novel oncolytic vaccinia virus carrying the human sodium iodide symporter.

    Directory of Open Access Journals (Sweden)

    Dana Haddad

    Full Text Available INTRODUCTION: Oncolytic viruses show promise for treating cancer. However, to assess therapy and potential toxicity, a noninvasive imaging modality is needed. This study aims to determine the in vivo biodistribution, and imaging and timing characteristics of a vaccinia virus, GLV-1h153, encoding the human sodium iodide symporter (hNIS. METHODS: GLV-1h153 was modified from GLV-1h68 to encode the hNIS gene. Timing of cellular uptake of radioiodide (131I in human pancreatic carcinoma cells PANC-1 was assessed using radiouptake assays. Viral biodistribution was determined in nude mice bearing PANC-1 xenografts, and infection in tumors confirmed histologically and optically via Green Fluorescent Protein (GFP and bioluminescence. Timing characteristics of enhanced radiouptake in xenografts were assessed via (124I-positron emission tomography (PET. Detection of systemic administration of virus was investigated with both (124I-PET and 99m-technecium gamma-scintigraphy. RESULTS: GLV-1h153 successfully facilitated time-dependent intracellular uptake of (131I in PANC-1 cells with a maximum uptake at 24 hours postinfection (P<0.05. In vivo, biodistribution profiles revealed persistence of virus in tumors 5 weeks postinjection at 10(9 plaque-forming unit (PFU/gm tissue, with the virus mainly cleared from all other major organs. Tumor infection by GLV-1h153 was confirmed via optical imaging and histology. GLV-1h153 facilitated imaging virus replication in tumors via PET even at 8 hours post radiotracer injection, with a mean %ID/gm of 3.82 ± 0.46 (P<0.05 2 days after intratumoral administration of virus, confirmed via tissue radiouptake assays. One week post systemic administration, GLV-1h153-infected tumors were detected via (124I-PET and 99m-technecium-scintigraphy. CONCLUSION: GLV-1h153 is a promising oncolytic agent against pancreatic cancer with a promising biosafety profile. GLV-1h153 facilitated time-dependent hNIS-specific radiouptake in pancreatic

  3. Dismantling the "Red Wall" of Colloidal Perovskites: Highly Luminescent Formamidinium and Formamidinium-Cesium Lead Iodide Nanocrystals.

    Science.gov (United States)

    Protesescu, Loredana; Yakunin, Sergii; Kumar, Sudhir; Bär, Janine; Bertolotti, Federica; Masciocchi, Norberto; Guagliardi, Antonietta; Grotevent, Matthias; Shorubalko, Ivan; Bodnarchuk, Maryna I; Shih, Chih-Jen; Kovalenko, Maksym V

    2017-03-28

    Colloidal nanocrystals (NCs) of APbX 3 -type lead halide perovskites [A = Cs + , CH 3 NH 3 + (methylammonium or MA + ) or CH(NH 2 ) 2 + (formamidinium or FA + ); X = Cl - , Br - , I - ] have recently emerged as highly versatile photonic sources for applications ranging from simple photoluminescence down-conversion (e.g., for display backlighting) to light-emitting diodes. From the perspective of spectral coverage, a formidable challenge facing the use of these materials is how to obtain stable emissions in the red and infrared spectral regions covered by the iodide-based compositions. So far, red-emissive CsPbI 3 NCs have been shown to suffer from a delayed phase transformation into a nonluminescent, wide-band-gap 1D polymorph, and MAPbI 3 exhibits very limited chemical durability. In this work, we report a facile colloidal synthesis method for obtaining FAPbI 3 and FA-doped CsPbI 3 NCs that are uniform in size (10-15 nm) and nearly cubic in shape and exhibit drastically higher robustness than their MA- or Cs-only cousins with similar sizes and morphologies. Detailed structural analysis indicated that the FAPbI 3 NCs had a cubic crystal structure, while the FA 0.1 Cs 0.9 PbI 3 NCs had a 3D orthorhombic structure that was isostructural to the structure of CsPbBr 3 NCs. Bright photoluminescence (PL) with high quantum yield (QY > 70%) spanning red (690 nm, FA 0.1 Cs 0.9 PbI 3 NCs) and near-infrared (near-IR, ca. 780 nm, FAPbI 3 NCs) regions was sustained for several months or more in both the colloidal state and in films. The peak PL wavelengths can be fine-tuned by using postsynthetic cation- and anion-exchange reactions. Amplified spontaneous emissions with low thresholds of 28 and 7.5 μJ cm -2 were obtained from the films deposited from FA 0.1 Cs 0.9 PbI 3 and FAPbI 3 NCs, respectively. Furthermore, light-emitting diodes with a high external quantum efficiency of 2.3% were obtained by using FAPbI 3 NCs.

  4. The feasibility of using a baculovirus vector to deliver the sodium-iodide symporter gene as a reporter

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Xiang; Li Biao; Wang Jun; Yin Hongyan [Department of Nuclear Medicine, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025 (China); Zhang Yifan [Department of Nuclear Medicine, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025 (China)], E-mail: zhangyifan1992@yahoo.com.cn

    2010-04-15

    Purpose: To evaluate the efficiency of baculovirus vectors in transducing FTC-133 cells and to examine the feasibility of using baculovirus vectors for the delivery of the sodium-iodide symporter (NIS) gene as a reporter through co-transduction to monitor the expression of the target gene. Method: Two recombinant baculoviruses were constructed to express NIS and green fluorescent protein (GFP) respectively. FTC-133, 8050C, SW1116, A549 cells, were infected with Bac-GFP. The infection efficiency of Bac-GFP and the intensity of fluorescence, in either the presence or absence of sodium butyrate, were monitored by flow cytometry. The iodine uptake by FTC-133 cells infected with Bac-NIS was measured using a {gamma} counter. FTC-133 cells were infected with a mixture of equal amounts of Bac-NIS and Bac-GFP at different setting of multiplicity of infection (MOI). The changes of GFP fluorescence intensity and iodine uptake were monitored 24 h after infection in the coinfected cells. Results: We have successfully constructed recombinant baculoviruses carrying NIS and GFP under the control of the cytomegalovirus IE-1 promoter. We found that transduced efficiency of baculovirus in 8505C, SW1116, A549 cells are low in absence of sodium butyrate. Yet Bac-GFP infects FTC-133 cells at a high efficiency, 77.67%, 85.57% and 93.23% with MOI of 100, 200 and 400, respectively. The fluorescence intensity of the Bac-GFP infected tumor cells correlated positively with the MOI of the virus. Sodium butyrate induction increased both the infection efficiency and the fluorescence intensity, but increase of infection efficiency was insignificant in FTC-133 cells. Reporter gene (GFP) expression in FTC-133 is stable within 7 days after infection. The radioactivity incorporated by the tumor cells infected with Bac-NIS correlated positively with the MOI of Bac-NIS as well. In tumor cells co-infected with Bac-NIS and Bac-GFP, the amount of radioactivity incorporated significantly correlated with

  5. Baculovirus vector-mediated transfer of sodium iodide symporter and plasminogen kringle 5 genes for tumor radioiodide therapy.

    Directory of Open Access Journals (Sweden)

    Min Zhang

    Full Text Available BACKGROUND: Both tumor cells and their supporting endothelial cells should be considered for targeted cell killing when designing cancer treatments. Here we investigated the feasibility of combining radioiodide and antiangiogenic therapies after baculovirus-mediated transfer of genes encoding the sodium iodide symporter (NIS and plasminogen kringle 5 (K5. METHODS: A recombinant baculovirus containing the NIS gene under control of the human telomerase reverse transcriptase (hTERT promoter and the K5 gene driven by the early growth response 1 (Egr1 promoter was developed. Dual-luciferase reporter assay was performed to confirm the activation of hTERT transcription. NIS and K5 gene expression were identified by Western blot and Real-Time PCR. Functional NIS activity in baculovirus-infected Hela cells was confirmed by the uptake of 125I and cytotoxicity of 131I. The apoptotic effect of 131I-induced K5 on baculovirus-infected human umbilical vein endothelial cells (HUVECs was analyzed by a flow cytometry-based assay. In vivo, NIS reporter gene imaging and therapeutic experiments with 131I were performed. Finally, the microvessel density (MVD in tumors after treatment was determined by CD31 immunostaining. RESULTS: The activation of hTERT transcription was specifically up-regulated in tumor cells. NIS gene expression markedly increased in baculovirus-infected HeLa cells, but not in MRC5 cells. The Hela cells showed a significant increase of 125I uptake, which was inhibited by NaClO4, and a notably decreased cell survival rate by 131I treatment. Expression of the K5 gene induced by 131I was elevated in a dose- and time-dependent manner and resulted in the apoptosis of HUVECs. Furthermore, 131I SPECT imaging clearly showed cervical tumor xenografts infected with recombinant baculovirus. Following therapy, tumor growth was significantly retarded. CD31 immunostaining confirmed a significant decrease of MVD. CONCLUSION: The recombinant baculovirus supports

  6. Potassium Iodide (KI)

    Science.gov (United States)

    ... FAQs Emergency Preparedness and You Coping with a Disaster or Traumatic Event Information on Specific Types of Emergencies Information for Specific Groups Resources for Emergency Health Professionals Training & Education Social Media What’s New Preparation & Planning More on Preparedness What ...

  7. Palladium-catalyzed one-pot three- or four-component coupling of aryl iodides, alkynes, and amines through C-N bond cleavage: efficient synthesis of indole derivatives.

    Science.gov (United States)

    Hao, Wei; Geng, Weizhi; Zhang, Wen-Xiong; Xi, Zhenfeng

    2014-02-24

    An efficient synthesis of N-substituted indole derivatives was realized by combining the Pd-catalyzed one-pot multicomponent coupling approach with cleavage of the C(sp(3))-N bonds. Three or four components of aryl iodides, alkynes, and amines were involved in this coupling process. The cyclopentadiene-phosphine ligand showed high efficiency. A variety of aryl iodides, including cyclic and acyclic tertiary amino aryl iodides, and substituted 1-bromo-2-iodobenzene derivatives could be used. Both symmetric and unsymmetric alkynes substituted with alkyl, aryl, or trimethylsilyl groups could be applied. Cyclic secondary amines such as piperidine, morpholine, 4-methylpiperidine, 1-methylpiperazine, 2-methylpiperidine, and acyclic amines including secondary and primary amines all showed good reactivity. Further application of the resulting indole derivatives was demonstrated by the synthesis of benzosilolo[2,3-b]indole. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Unraveling the Charge Extraction Mechanism of Perovskite Solar Cells Fabricated with Two-Step Spin Coating: Interfacial Energetics between Methylammonium Lead Iodide and C60.

    Science.gov (United States)

    Shin, Dongguen; Kang, Donghee; Jeong, Junkyeong; Park, Soohyung; Kim, Minju; Lee, Hyunbok; Yi, Yeonjin

    2017-11-02

    In organolead halide perovskite solar cells (PSCs), interfacial properties between the perovskite and charge transport layers are the critical factors governing charge extraction efficiency. In this study, the effect of interfacial energetics between two-step spin-coated methylammonium lead iodide (MAPbI 3 ) with different methylammonium iodide (MAI) concentrations and C 60 on the charge extraction efficiency is investigated. The electronic structures of perovskite films are significantly varied by the MAI concentrations due to the changes in the residual precursor and MA + defect content. As compared to the optimum PSCs with 25 mg mL -1 MAI, PSCs with other MAI concentrations show significantly lower power conversion efficiencies and severe hysteresis. The energy level alignment at the C 60 /MAPbI 3 interface determined by ultraviolet and inverse photoelectron spectroscopy measurements reveals the origin of distinct differences in device performances. The conduction band offset at the C 60 /MAPbI 3 interface plays a crucial role in efficient charge extraction in PSCs.

  9. Research paper effects of 13-HPODE on expression of genes involved in thyroid hormone synthesis, iodide uptake and formation of hydrogen peroxide in porcine thyrocytes.

    Science.gov (United States)

    Luci, Sebastian; Bettzieche, Anja; Brandsch, Corinna; Eder, Klaus

    2006-11-01

    It has been shown that dietary oxidized fats influence thyroid function in rats and pigs. Mechanism underlying this phenomenon are unknown. This study was performed to investigate whether 13-hydroperoxy-9,11 -octadecadienic acid (13-HPODE), a primary oxidation product of linoleic acid, affects expression of gene involved in thyroid hormone synthesis and formation of hydrogen peroxide in primary porcine thyrocytes. Thyrocytes were treated with 13-HPODE in concentrations between 20 and 100 microM. Cells treated with vehicle alone ("control cells") or with equivalent concentrations of linoleic acid were considered as controls. Treatment of cells with 13-HPODE did not affect cell viability but increased the activities of the antioxidant enzymes superoxide dismutase and glutathione peroxidase (p < 0.05) compared to control cells or cells treated with linoleic acid. Relative mRNA concentrations of genes involved in thyroid hormone synthesis like sodium iodide symporter, thyrotropin receptor, and thyroid peroxidase, as well as iodide uptake, did not differ between cells treated with 13-HPODE and control cells or cells treated with linoleic acid. Treatment of cells with 13-HPODE, however, reduced the relative mRNA concentrations of dual oxidase-2 and the formation of hydrogen peroxide compared to control cells or cells treated with linoleic acid (p < 0.05). Because the production of hydrogen peroxide is rate-limiting for the synthesis of thyroid hormones, it is suggested that 13-HPODE could have an impact on the formation of thyroid hormones in the thyroid gland.

  10. Carbazole Dye-Sensitized Solar Cells Studied from Femtoseconds to Seconds-Effect of Additives in Cobalt- and Iodide-Based Electrolytes.

    Science.gov (United States)

    Sobuś, Jan; Kubicki, Jacek; Burdziński, Gotard; Ziółek, Marcin

    2015-09-21

    Comprehensive studies of all charge-separation processes in efficient carbazole dye-sensitized solar cells are correlated with their photovoltaic parameters. An important role of partial, fast electron recombination from the semiconductor nanoparticles to the oxidized dye is revealed; this takes place on the picosecond and sub-nanosecond timescales. The charge-transfer dynamics in cobalt tris(bipyridyl) based electrolytes and iodide-based electrolyte is observed to depend on potential-determining additives in a similar way. Upon addition of 0.5 M 4-tert-butylpiridine to both types of electrolytes, the stability of the cells is greatly improved; the cell photovoltage increases by 150-200 mV, the electron injection rate decreases about five times (from 5 to 1 ps(-1) ), and fast recombination slows down about two to three times. Dye regeneration proceeds at a rate of about 1 μs(-1) in all electrolytes. Electron recombination from titania to cobalt electrolytes is much faster than that to iodide ones. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Construction of new iodide ion-selective electrodes based on new ionophores: comparison of the effect of structures and additives on electrode response.

    Science.gov (United States)

    Shokrollahi, Ardeshir; Ghaedi, Mehrorang; Kianfar, Ali Hossain; Montazerozohori, Morteza; Najibzadeh, Marziyeh

    2009-01-01

    New iodide ion-selective electrodes based on bis(2-methyl-3-phenyl-propenylidene)1,2-propanediamine)mercury(II) bromide [Hg(BMPPMB)Br2], bis (5-bromo salicylaldehyde) ethylenediimine vanadyl(IV) [VO(5-Br Salen)], and bis(5-bromo salicylaldehyde) ethylenediimine uranyl(VI) [UO2(5-Br Salen)] carriers are described. The electrodes exhibited Nernstian slopes of -58.3 +/- 1.0, -58.5 +/- 1.4, and -59.0 +/- 1.2 mV/decade for Hg(BMPPMB)Br2, VO(5-Br Salen), and UO2(5-Br Salen) iodide ion concentration in the range of 1.0 x 10(-6)-0.1 M, with detection limits of about 0.6, 0.5, and 0.3 microM, respectively. The potentiometric responses of the electrodes were independent of pH over the range 1.7-10.6, 2.2-11.3, and 2.1-11.1, with satisfactory reproducibility. The electrodes had response times of < or =5 s and could be used for at least 84, 80, and 100 days for Hg(BMPPMB)Br2, VO(5-Br Salen), and UO2(5-Br Salen), respectively, without any considerable divergence in their potential responses.

  12. Semiconducting tin and lead iodide perovskites with organic cations: phase transitions, high mobilities, and near-infrared photoluminescent properties.

    Science.gov (United States)

    Stoumpos, Constantinos C; Malliakas, Christos D; Kanatzidis, Mercouri G

    2013-08-05

    A broad organic-inorganic series of hybrid metal iodide perovskites with the general formulation AMI3, where A is the methylammonium (CH3NH3(+)) or formamidinium (HC(NH2)2(+)) cation and M is Sn (1 and 2) or Pb (3 and 4) are reported. The compounds have been prepared through a variety of synthetic approaches, and the nature of the resulting materials is discussed in terms of their thermal stability and optical and electronic properties. We find that the chemical and physical properties of these materials strongly depend on the preparation method. Single crystal X-ray diffraction analysis of 1-4 classifies the compounds in the perovskite structural family. Structural phase transitions were observed and investigated by temperature-dependent single crystal X-ray diffraction in the 100-400 K range. The charge transport properties of the materials are discussed in conjunction with diffuse reflectance studies in the mid-IR region that display characteristic absorption features. Temperature-dependent studies show a strong dependence of the resistivity as a function of the crystal structure. Optical absorption measurements indicate that 1-4 behave as direct-gap semiconductors with energy band gaps distributed in the range of 1.25-1.75 eV. The compounds exhibit an intense near-IR photoluminescence (PL) emission in the 700-1000 nm range (1.1-1.7 eV) at room temperature. We show that solid solutions between the Sn and Pb compounds are readily accessible throughout the composition range. The optical properties such as energy band gap, emission intensity, and wavelength can be readily controlled as we show for the isostructural series of solid solutions CH3NH3Sn(1-x)Pb(x)I3 (5). The charge transport type in these materials was characterized by Seebeck coefficient and Hall-effect measurements. The compounds behave as p- or n-type semiconductors depending on the preparation method. The samples with the lowest carrier concentration are prepared from solution and are n-type; p

  13. Synthesis of the diphenylacetylene-based, tetra-amine ligand 12,-bis(3,5-bis[(dimethylamino)metyl)acetylene by palladium-catalysed cross-coupling : Isolation and crystal structure of the catalyst trans-(3,5-bis[(dimethylamino)methyl]-phenyl)bis(triphenylphosphine palladium(II) iodide

    NARCIS (Netherlands)

    Koten, G. van; Spee, M.P.R.; Ader, B.A.; Steenwinkel, P.; Kooijman, H.; Spek, A.L.

    2000-01-01

    Reaction of 3, 5-bis[(dimethylamino)methyl]phenyl iodide with 3,5-bis[(dimethylamino)methyl]phenylacetylene in diethylamine in the presence of bis(triphenylphosphine)palladium(II) dichloride (3.6 mol%) and copper(I) iodide (3.0 mol%) gave 1,2-(bis(3,5-bis[(dimethylamino)methyl]phenyl)acetylene (1)

  14. Feasibility of dual reporter gene in rat myoblast cell line using human sodium iodide symporter (hNIS) and enhanced green fluorescent protein (EGFP) gene

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Jin; Lee, You La; Ahn, Sohn Joo; Choi, Chang Ik; Lee, Sang Woo; Ahn, Byeong Cheol; Lee, Jae Tae [School of Medicine, Kyungpook National University, Daegu (Korea, Republic of)

    2007-07-01

    To develop a non-invasive combined imaging method of gamma camera and optical imaging to assess rat myoblast cell line, H9c2, we constructed retrovirus containing hNIS and EGFP gene, and transfected to rat myoblast cell and monitored hNIS and EGFP expression. Rat myoblast cell line, H9C2, was transfected with hNIS and EGFP gene using retrovirus (H9C2-NG). The expression of hNIS and EGFP gene was determined by RT-PCR and fluorescence microscopy, respectively. The uptake and efflux of I-125 were measured in the transfected and wild type cell lines. Each cell line was injected to 4 flank sites (H9c2: 1X107 or 2X107, H9C2-NG: 1X107 or 2X107) in nude mouse. Scintigraphic image was performed at 3h, 1 day after H9C2 and H9C2-NG cell inoculation. We performed gamma camera and animal PET imaging to evaluate NIS expression. Also, GFP image obtained using optical imaging system. The expression of hNIS and EGFP gene was confirmed by RT-PCR. In iodide uptake, H9C2-NG cells accumulated 274.52.2 pmol/ mg protein at 30 min. But wild type cell line did not uptake iodide. In fluorescent microscopy, H9C2-NG cells were highly fluorescent than that of H9C2 cells. In iodide efflux study, 50% of radioactivity flowed out during the first 10min. Scintigraphy showed increased uptake of Tc-99m in H9c2-NG than in H9C2 for 1 day. Also, H9C2-NG cells showed high signal-to-background fluorescent spots in animal body. In this study, NIS and EGFP reporter gene were successfully transfected by a retrovirus in myoblast cell line, and the transfected cell can be easily visualized in vivo. These results suggest that NIS and EGFP gene has an excellent feasibility as a reporter gene, and it can be used to monitor cell trafficking for monitoring.

  15. Determination of high mitochondrial membrane potential in spermatozoa loaded with the mitochondrial probe 5,5',6,6'tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyanine iodide (JC-1) using flow cytometry.

    Science.gov (United States)

    A flow cytometric method was developed to identify viable, energized sperm cells with high mitochondrial inner transmembrane potential (''m), > 80-100 mV using the mitochondrial probe 5, 5', 6, 6'-tetrachloro-1, 1', 3, 3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) and the impermeant nuclear ...

  16. The heat capacity and density of solutions of barium and tetrabutylammonium iodides in N-methylpyrrolidone at 298.15 K

    Science.gov (United States)

    Novikov, A. N.; Lenina, O. F.; Vasilev, V. A.

    2009-03-01

    The heat capacity and density of solutions of barium and tetrabutylammonium iodides in N-methylpyrrolidone (MP) were studied at 298.15 K by calorimetry and densimetry. The standard partial molar heat capacities and volumes ( overline {C_{p^2 }^ circ } and overline {V_2^ circ } ) of the electrolytes in MP were calculated. The standard heat capacities overline {C_{pi}^ circ } and volumes overline {V_i^ circ } of the Ba2+ and (C4H9)4N+ ions in solution in MP at 298.15 K were determined. With the tetrabutylammonium ion, these values were in agreement with those calculated on the basis of the tetraphenylarsonium-tetraphenyl borate and tetraphenylphosphonium-tetraphenyl borate assumptions. The results are discussed in relation to the special features of solvation in solutions of the salts studied.

  17. Development of a kinetic model and calculation of radiation dose estimates for sodium iodide-{sup 131}I in athyroid individuals

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, M.

    1997-07-01

    The treatment for some thyroid carcinomas involves surgically removing the thyroid gland and administering the radiopharmaceutical Sodium iodide-{sup 131}I (NaI). A diagnostic dose of NaI is given to the patient to determine if remnant tissue from the gland remains or larger doses are administered in order to treat the malignant tissue. Past research regarding NaI uptake and retention in euthyroid individuals (normal functioning thyroid) reveal that radioiodine concentrates mainly in the thyroid tissue and the remaining material is excreted from the body. The majority of radioiodine in athyroid (without thyroid) individuals is also eliminated from the body; however, there has been recent evidence of a long-term retention phase for individuals with no radioiodine concentrating tissue. The general purpose of this study was to develop a kinetic model and estimate the absorbed dose to athyroid individuals regarding the distribution and retention of NaI.

  18. Modeling the effect of charge density in the active layers of reverse osmosis and nanofiltration membranes on the rejection of arsenic(III) and potassium iodide.

    Science.gov (United States)

    Coronell, Orlando; Mi, Baoxia; Mariñas, Benito J; Cahill, David G

    2013-01-02

    We used an extended solution-diffusion model that incorporates Donnan electrostatic exclusion of ions and unhindered advection due to imperfections, and measurements of charge density in the polyamide active layers of reverse osmosis (RO) and nanofiltration (NF) membranes, to predict the rejection of a strong electrolyte (i.e., potassium iodide) and a weak acid (i.e., arsenious acid) as a function of the pH of the feed aqueous solution. Predictions of solute rejection were in agreement with experimental data indicating that (i) the extended solution-diffusion model taking into account Donnan exclusion and unhindered advection due to imperfections satisfactorily describes the effect of pH on solute rejection by RO/NF membranes and (ii) measurement of charge density in active layers provides a valuable characterization of RO/NF membranes. Our results and analysis also indicate that independent ions, and not ion pairs, dominate the permeation of salts.

  19. Evidence that an iodolactone mediates the inhibitory effect of iodide on thyroid cell proliferation but not on adenosine 3',5'-monophosphate formation.

    Science.gov (United States)

    Dugrillon, A; Bechtner, G; Uedelhoven, W M; Weber, P C; Gärtner, R

    1990-07-01

    Iodolactone (6-iodo-8,11,14-eicosatrienoic-delta-lactone), an iodinated derivative of arachidonic acid, was found to be synthesized in rat thyroid slices; however, the physiological role of this compound is still unknown. We tried to detect iodolactone in isolated porcine thyroid follicles and investigated the effects of in vitro synthesized iodolactone on epidermal growth factor-induced thyroid cell proliferation and TSH-induced cAMP formation. In vitro synthesis of iodolactone was performed with lactoperoxidase-catalyzed iodination of arachidonic acid in the presence of trace amounts of [125I]- and [3H]arachidonic acid. After purification by silica gel chromatography, HPLC of the reaction products revealed one main peak containing trace amounts of both [125I]- and [3H]arachidonic acid. With gas chromatography-mass spectrometry (GC-MS) a molecular mass of 391 m/z, corresponding to the derivatization product of iodolactone, was found. An ethanol-chloroform extract of isolated thyroid follicles preincubated with KI (10 microM) and arachidonic acid (1 microM) revealed peaks in HPLC and GC comparable with those of in vitro synthesized iodolactone. This indicates the ability of thyroid follicles to form iodolactone. Iodolactone (0.1-1.0 microM) dose-dependently inhibited epidermal growth factor-induced thyroid cell growth. This growth-inhibiting effect of iodolactone was 50-fold more pronounced than the inhibitory effect of KI (4 X 10(-5) microM) on thyroid cell proliferation. In contrast to the effect of iodide, the inhibitory effect of iodolactone on thyroid cell growth could not be abolished by methimazole (1 mM). Basal as well as TSH (0.5 U/liter)-induced cAMP formation were not changed by iodolactone. These experiments suggest a physiological role of iodolactone as a mediator of the known inhibitory effect of iodide on thyroid growth.

  20. Mesenchymal stem cell-mediated, tumor stroma-targeted radioiodine therapy of metastatic colon cancer using the sodium iodide symporter as theranostic gene.

    Science.gov (United States)

    Knoop, Kerstin; Schwenk, Nathalie; Schmohl, Kathrin; Müller, Andrea; Zach, Christian; Cyran, Clemens; Carlsen, Janette; Böning, Guido; Bartenstein, Peter; Göke, Burkhard; Wagner, Ernst; Nelson, Peter J; Spitzweg, Christine

    2015-04-01

    The tumor-homing property of mesenchymal stem cells (MSCs) allows targeted delivery of therapeutic genes into the tumor microenvironment. The application of sodium iodide symporter (NIS) as a theranostic gene allows noninvasive imaging of MSC biodistribution and transgene expression before therapeutic radioiodine application. We have previously shown that linking therapeutic transgene expression to induction of the chemokine CCL5/RANTES allows a more focused expression within primary tumors, as the adoptively transferred MSC develop carcinoma-associated fibroblast-like characteristics. Although RANTES/CCL5-NIS targeting has shown efficacy in the treatment of primary tumors, it was not clear if it would also be effective in controlling the growth of metastatic disease. To expand the potential range of tumor targets, we investigated the biodistribution and tumor recruitment of MSCs transfected with NIS under control of the RANTES/CCL5 promoter (RANTES-NIS-MSC) in a colon cancer liver metastasis mouse model established by intrasplenic injection of the human colon cancer cell line LS174t. RANTES-NIS-MSCs were injected intravenously, followed by (123)I scintigraphy, (124)I PET imaging, and (131)I therapy. Results show robust MSC recruitment with RANTES/CCL5-promoter activation within the stroma of liver metastases as evidenced by tumor-selective iodide accumulation, immunohistochemistry, and real-time polymerase chain reaction. Therapeutic application of (131)I in RANTES-NIS-MSC-treated mice resulted in a significant delay in tumor growth and improved overall survival. This novel gene therapy approach opens the prospect of NIS-mediated radionuclide therapy of metastatic cancer after MSC-mediated gene delivery. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  1. Sensitivity and Specificity of Dual-Isotope 99mTc-Tetrofosmin and 123I Sodium Iodide Single Photon Emission Computed Tomography (SPECT) in Hyperparathyroidism.

    Science.gov (United States)

    Sommerauer, Michael; Graf, Carmen; Schäfer, Niklaus; Huber, Gerhard; Schneider, Paul; Wüthrich, Rudolf; Schmid, Christoph; Steinert, Hans

    2015-01-01

    Despite recommendations for 99mTc-tetrofosmin dual tracer imaging for hyperparathyroidism in current guidelines, no report was published on dual-isotope 99mTc-tetrofosmin and 123I sodium iodide single-photon-emission-computed-tomography (SPECT). We evaluated diagnostic accuracy and the impact of preoperative SPECT on the surgical procedures and disease outcomes. Analysis of 70 consecutive patients with primary hyperparathyroidism and 20 consecutive patients with tertiary hyperparathyroidism. Imaging findings were correlated with surgical results. Concomitant thyroid disease, pre- and postoperative laboratory measurements, histopathological results, type and duration of surgery were assessed. In primary hyperparathyroidism, SPECT had a sensitivity of 80% and a positive predictive value of 93% in patient-based analysis. Specificity was 99% in lesion-based analysis. Patients with positive SPECT elicit higher levels of parathyroid hormone and higher weight of resected parathyroids than SPECT-negative patients. Duration of parathyroid surgery was on average, approximately 40 minutes shorter in SPECT-positive than in SPECT-negative patients (89 ± 46 vs. 129 ± 41 minutes, p = 0.006); 86% of SPECT-positive and 50% of SPECT-negative patients had minimal invasive surgery (p = 0.021). SPECT had lower sensitivity (60%) in patients with tertiary hyperparathyroidism; however, 90% of these patients had multiple lesions and all of these patients had bilateral lesions. Dual-isotope SPECT with 99mTc-tetrofosmin and 123I sodium iodide has a high diagnostic value in patients with primary hyperparathyroidism and allows for saving of operation time. Higher levels of parathyroid hormone and higher glandular weight facilitated detection of parathyroid lesion. Diagnostic accuracy of preoperative imaging was lower in patients with tertiary hyperparathyroidism.

  2. Electrochemical Study of Iodide in the Presence of Phenol and o-Cresol: Application to the Catalytic Determination of Phenol and o-Cresol

    Directory of Open Access Journals (Sweden)

    Davood Nematollahi

    2004-11-01

    Full Text Available Abstract: The electrochemical oxidation of iodide in the presence of phenol and o-cresol was investigated at a glassy carbon electrode in buffered media by cyclic voltammetry, linear sweep voltammetry and controlled–potential coulometry. The experimental results indicate that the phenol and o-cresol convert to their derivatives after participating in a halogenation coupled reaction (quasi-catalytic reaction following the oxidation of iodide to iodine. The concentrations of phenol and o-cresol have been determined in aqueous solutions according to the linear dependence of quasi-catalytic peak currents with the concentration. The calibration graphs show two linear sections of 0.0 to 1.0×10-4 M and 2.0×10-4 to 1.0 ×10-3 M for phenol and 4.2×10-5 to 1.0×10-4 M and 2.0×10-4 to 1.0×10-3 M for o-cresol. The theoretical detection limits and the relative standard deviations for ten measurements of phenol and o-cresol are 1.125×10-5 M, 1.06% and 4.201×10-5 M, 1.44%, respectively.

  3. Potassium doped methylammonium lead iodide (MAPbI3) thin films as a potential absorber for perovskite solar cells; structural, morphological, electronic and optoelectric properties

    Science.gov (United States)

    Muzammal uz Zaman, Muhammad; Imran, Muhammad; Saleem, Abida; Kamboh, Afzal Hussain; Arshad, Muhammad; Khan, Nawazish Ali; Akhter, Parvez

    2017-10-01

    In this article, we have demonstrated the doping of K in the light absorbing CH3NH3PbI3 perovskite i.e. (M = CH3, A = NH3; x = 0-1). One of the major merits of methylammonium lead iodide (CH3NH3PbI3) perovskites is that they act as efficient absorbing material of light in photovoltaic cell imparting long carrier lifetime and optimum band gap. The structural, morphological, electronic and optoelectric properties of potassium (K) doped light absorber methylammonium lead iodide (CH3NH3PbI3) perovskites are reported here i.e. Kx(MA)1-xPbI3 (M = CH3, A =NH3; x = 0-1). The thin films of perovskites (x = 0-1) were deposited by spin coating on cleaned FTO substrates and characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), current-voltage (IV), X-ray photoelectron spectroscopy (XPS) and Diffused reflectance spectroscopy (DRS) analysis. The organic constituents i.e. MA = CH3NH3, in perovskites solar cells induce instability even at the room temperature. To overcome such instabilities we have replaced the organic constituents by K because both of them have electropositive nature. Potassium successfully replaces the CH3NH3. Initially, this compound grows in a tetragonal crystal structure, however, beyond 30% doping of potassium orthorhombic distortions are induced in the parent tetragonal unit cell. Such phase transformation is microscopically visible in the electron micrographs of doped samples; cubic grains for MAPbI3 begin to transform into strip like structures in K-doped samples. The resistance of the samples is decreased for partial K-doping, which we suggested to be arising due to the electropositive nature of K. It is observed that the binding energy difference between Pb4f and I3d core levels are very similar in all the investigated systems and show formal oxidation states. Also, the partially doped samples showed increased absorption and bandgaps around 1.5 eV which is an optimum value for solar absorption.

  4. Spectroscopic analysis of lithium terbium tetrafluoride

    DEFF Research Database (Denmark)

    Christensen, H.P.

    1978-01-01

    . The rare-earth site in LiTbF4 possesses S4 symmetry, which allows six crystal-field parameters. ζ and the six Bim were varied to obtain the best agreement with the experimentally observed levels. Keeping F2=434 cm-1 fixed, a fit with a standard deviation of 12 cm-1 was obtained at 10 K with the following...... were calculated by diagonalizing an effective spin-orbit and crystal-field Hamiltonian in an LS basis. H=Σλi(L→·S→)i+ΣαiΣBimOim, where the parameters λi are functions of the spin-orbit parameter ζ and the Slater parameter F2. The Oim and αi are Racah operators and reduced matrix elements, respectively...

  5. Inelastic critical scattering of neutrons from terbium

    DEFF Research Database (Denmark)

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

    1967-01-01

    We have measured the inelasticity of the critical neutron scattering in Tb above the Néel temperature. The results show that dynamical slowing down of fluctuations does occur at a second order phase transition.......We have measured the inelasticity of the critical neutron scattering in Tb above the Néel temperature. The results show that dynamical slowing down of fluctuations does occur at a second order phase transition....

  6. SAD phasing of a structure based on cocrystallized iodides using an in-house Cu Kalpha X-ray source: effects of data redundancy and completeness on structure solution.

    Science.gov (United States)

    Yogavel, Manickam; Gill, Jasmita; Mishra, Prakash Chandra; Sharma, Amit

    2007-08-01

    Superoxide dismutase (SOD) from Potentilla atrosanguinea (Wall. ex. Lehm.) was crystallized using 20% PEG 3350 and 0.2 M ammonium iodide and diffraction data were collected to 2.36 A resolution using an in-house Cu Kalpha X-ray source. Analyses show that data with a redundancy of 3.2 were sufficient to determine the structure by the SAD technique using the iodine anomalous signal. This redundancy is lower than that in previous cases in which protein structures were determined using iodines for phasing and in-house copper X-ray sources. Cocrystallization of proteins with halide salts such as ammonium iodide in combination with copper-anode X-ray radiation can therefore serve as a powerful and easy avenue for structure solution.

  7. Iodidimonas muriae gen. nov., sp. nov., an aerobic iodide-oxidizing bacterium isolated from brine of a natural gas and iodine recovery facility, and proposals of Iodidimonadaceae fam. nov., Iodidimonadales ord. nov., Emcibacteraceae fam. nov. and Emcibacterales ord. nov.

    Science.gov (United States)

    Iino, Takao; Ohkuma, Moriya; Kamagata, Yoichi; Amachi, Seigo

    2016-12-01

    A chemo-organotrophic iodide (I-)-oxidizing bacterial strain, C-3T, isolated from natural gas brine of an iodine recovery facility in Kujukuri, Chiba, Japan, was characterized for representation of a novel species in the class Alphaproteobacteria. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the nearest neighbours of strain C-3T were members of the genera Eilatimonas, Kordiimonas, Rhodothalassium and Temperatibacter with 88-91 % sequence similarity. Cells of strain C-3T were aerobic, Gram-staining-negative, non-sporulating and rod-shaped (1.3-3.6 µm in length). Strain C-3T grew optimally at 30 °C, pH 7.5 and with 3 % NaCl (w/v). Iodide oxidation to form molecular iodine (I2) was a unique trait for strain C-3T, whereas the strain did not utilize iodide as a sole electron donor for chemolithoautotrophic growth. The major isoprenoid quinone was Q-10. The major cellular fatty acids were C18 : 1ω7c and C16 : 1ω5c. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and unidentified aminolipids. The G+C content of the genomic DNA was 58.5 mol%. Iodide oxidation and the major cellular fatty acids composition distinguished strain C-3T from phylogenetically related bacteria. On the basis of the phenotypic features and the phylogenetic position, a novel genus and species are proposed for strain C-3T (=JCM 17843T=LMG 28660T), to be named Iodidimonas muriae gen. nov., sp. nov. We also propose to place the distinct sublineages of the genera Iodidimonasgen. nov. and Emcibacter in the orders Iodidimonadales ord. nov. and Emcibacterales ord. nov., respectively, because these genera are located far apart from the order Kordiimonadales and form the distinct lineage in the class Alphaproteobacteria.

  8. Replacement of a photomultiplier tube in a 2-inch thallium-doped sodium iodide gamma spectrometer with silicon photomultipliers and a light guide

    Directory of Open Access Journals (Sweden)

    Chankyu Kim

    2015-06-01

    Full Text Available The thallium-doped sodium iodide [NaI(Tl] scintillation detector is preferred as a gamma spectrometer in many fields because of its general advantages. A silicon photomultiplier (SiPM has recently been developed and its application area has been expanded as an alternative to photomultiplier tubes (PMTs. It has merits such as a low operating voltage, compact size, cheap production cost, and magnetic resonance compatibility. In this study, an array of SiPMs is used to develop an NaI(Tl gamma spectrometer. To maintain detection efficiency, a commercial NaI(Tl 2′ × 2′ scintillator is used, and a light guide is used for the transport and collection of generated photons from the scintillator to the SiPMs without loss. The test light guides were fabricated with polymethyl methacrylate and reflective materials. The gamma spectrometer systems were set up and included light guides. Through a series of measurements, the characteristics of the light guides and the proposed gamma spectrometer were evaluated. Simulation of the light collection was accomplished using the DETECT 97 code (A. Levin, E. Hoskinson, and C. Moison, University of Michigan, USA to analyze the measurement results. The system, which included SiPMs and the light guide, achieved 14.11% full width at half maximum energy resolution at 662 keV.

  9. Effects of lithium iodide doping on devolatilization characteristics of brown coals; Yoka lithium no tenka ga kattan no kanetsu henka katei ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Muraoka, J.; Kumagai, H.; Hayashi, J.; Chiba, T. [Hokkaido University, Sapporo (Japan)

    1996-10-28

    In order to discuss effects of lithium iodide (LiI) doping on condensation structure of brown coals during heating, spectral changes were measured by using an in-situ FT-IR. It was found that the LiI doping accelerates weight reduction due to heating, and the doping effect is affected by coal structure. Both of Loy Yang (LY) coal and its LiI doped coal (DLY) had absorption intensity of the FT-IR spectra decreased with rising temperature, and the absorption center belonging to an OH group shows different shifts between the LY and DLY coals. This indicates that the LiI doping has affected the change in hydrogen bonding patterns associated with heating. Both of South Banko (SB) and LY coals had the absorption spectral intensity in the OH group decreased as the weight reduction (conversion) rate increased. Reduction in the OH groups associated with heating is caused by volatilization and condensation reaction in light-gravity fraction. However, in the case of equal conversion rate, the LiI doped coal shows higher spectral intensity than the original coal, with the LiI doping suppressing reduction in the OH groups. It appears that the doping suppresses the condensation reaction between the OH groups. 2 refs., 6 figs., 1 tab.

  10. Low-bandgap mixed tin–lead iodide perovskite absorbers with long carrier lifetimes for all-perovskite tandem solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Dewei; Yu, Yue; Wang, Changlei; Liao, Weiqiang; Shrestha, Niraj; Grice, Corey R.; Cimaroli, Alexander J.; Guan, Lei; Ellingson, Randy J.; Zhu, Kai; Zhao, Xingzhong; Xiong, Ren-Gen; Yan, Yanfa

    2017-03-01

    Tandem solar cells using only metal-halide perovskite sub-cells are an attractive choice for next-generation solar cells. However, the progress in developing efficient all-perovskite tandem solar cells has been hindered by the lack of high-performance low-bandgap perovskite solar cells. Here, we report efficient mixed tin-lead iodide low-bandgap (~1.25 eV) perovskite solar cells with open-circuit voltages up to 0.85 V and over 70% external quantum efficiencies in the infrared wavelength range of 700-900 nm, delivering a short-circuit current density of over 29 mA cm-2 and demonstrating suitability for bottom-cell applications in all-perovskite tandem solar cells. Our low-bandgap perovskite solar cells achieve a maximum power conversion efficiency of 17.6% and a certified efficiency of 17.01% with a negligible current-voltage hysteresis. When mechanically stacked with a ~1.58 eV bandgap perovskite top cell, our best all-perovskite 4-terminal tandem solar cell shows a steady-state efficiency of 21.0%.

  11. High-Porosity Carbon Processed from Mixtures of Furfuryl Resin-Poly(ethylene glycol-Benzenesulfonyl Chloride and Its Application for Catalyzing Tri-iodide Reduction

    Directory of Open Access Journals (Sweden)

    Xu Shunjian

    2017-01-01

    Full Text Available High-porosity carbon (HPC was first prepared from a novel mixture system of furfuryl resin as carbon-yielding precursor, poly(ethylene glycol with low molecular weight as pore-forming agent and benzenesulfonyl chloride (BSC as cured catalyst, and then employed as catalyst for counter electrode in dye-sensitized solar cells (DSCs. The pore structures of HPC are tailored by changing BSC amount from 2% to 14%. Especially, when BSC amount ascends from 4% to 8%, the apparent porosity of HPC rises from 59.58% to 68.02% and the median pore size from 0.429 to 3.164 μm, except that some globular carbons initially occur on the carbon skeleton. Since the HPC derived from 4% BSC has high porosity and the most quantity of small-sized pores to enlarge its surface area allowing for the most catalytic active sites for tri-iodide reduction, the resulted counter electrode exhibits the best catalytic activity and the highest efficiency for use in DSCs.

  12. Unprecedented transformation of [I(-)·I3(-)] to [I4(2-)] polyiodides in the solid state: structures, phase transitions and characterization of dipyrazolium iodide triiodide.

    Science.gov (United States)

    Węcławik, M; Szklarz, P; Medycki, W; Janicki, R; Piecha-Bisiorek, A; Zieliński, P; Jakubas, R

    2015-11-14

    Dipyrazolium iodide triiodide, [C3N2H5(+)]2[I(-)·I3(-)], has been synthesized and studied by means of X-ray diffraction, differential scanning calorimetry, dielectric measurements, and UV-Vis spectroscopy. Two reversible, solid-solid phase transitions (Imma (I) ↔ (II) ↔Pbam (III)) at 254 K and 182/188 K respectively have been revealed. The anionic network experiences spectacular changes associated with a huge rebuilding of the inorganic network from [I(-)·I3(-)] to [I4(2-)]. The low frequency dielectric relaxation process occurs in phase II with the activation energy of ca. 34 kJ mol(-1). The molecular motion of the pyrazolium cations in [C3N2H5(+)]2[I(-)·I3(-)] has been studied by means of proton magnetic resonance studies ((1)H NMR). The ferroelastic properties of all phases have been confirmed by polarizing microscopy observations. The molecular mechanism of the phase transitions in the compound is proposed.

  13. Mitochondrial Respiratory Chain Inhibitors Involved in ROS Production Induced by Acute High Concentrations of Iodide and the Effects of SOD as a Protective Factor

    Directory of Open Access Journals (Sweden)

    Lingyan Wang

    2015-01-01

    Full Text Available A major source of reactive oxygen species (ROS generation is the mitochondria. By using flow cytometry of the mitochondrial fluorescent probe, MitoSOX Red, western blot of mitochondrial ROS scavenger Peroxiredoxin (Prx 3 and fluorescence immunostaining, ELISA of cleaved caspases 3 and 9, and TUNEL staining, we demonstrated that exposure to 100 μM KI for 2 hours significantly increased mitochondrial superoxide production and Prx 3 protein expression with increased expressions of cleaved caspases 3 and 9. Besides, we indicated that superoxide dismutase (SOD at 1000 unit/mL attenuated the increase in mitochondrial superoxide production, Prx 3 protein expression, and lactate dehydrogenase (LDH release and improved the relative cell viability at 100 μM KI exposure. However, SOD inhibitor diethyldithiocarbamic acid (DETC (2 mM, Rotenone (0.5 μM, a mitochondrial complex I inhibitor, and Antimycin A (10 μM, a complex III inhibitor, caused an increase in mitochondrial superoxide production, Prx 3 protein expression, and LDH release and decreased the relative cell viability. We conclude that the inhibitors of mitochondrial respiratory chain complex I or III may be involved in oxidative stress caused by elevated concentrations of iodide, and SOD demonstrates its protective effect on the Fischer rat thyroid cell line (FRTL cells.

  14. Cellulose Fibers Constructed Convenient Recyclable 3D Graphene-Formicary-like δ-Bi2O3 Aerogels for the Selective Capture of Iodide.

    Science.gov (United States)

    Xiong, Ye; Dang, Baokang; Wang, Chao; Wang, Hanwei; Zhang, Shouwei; Sun, Qingfeng; Xu, Xijin

    2017-06-21

    Radioiodine is highly radioactive and acutely toxic, which can be a serious health threat, and requires effective control. To fully utilize an adsorbent and reduce the overall production cost, successive recycling applications become necessary. Here, 3D formicary-like δ-Bi2O3 (FL-δ-Bi2O3) aerogel adsorbents were synthesized using a one-pot hydrothermal method. In this hybrid structure, abundant flowerlike δ-Bi2O3 (MR-δ-Bi2O3) microspheres were inlaid into the interconnected ant nest channel, forming a 3D hierarchical structure, which is applied as an efficient adsorbent with easy recovery for radioiodine removal. Notably, the FL-δ-Bi2O3 aerogel adsorbent exhibited a very high uptake capacity of 2.04 mmol/g by forming an insoluble Bi4I2O5 phase. Moreover, the FL-δ-Bi2O3 worked in a wide pH range of 4-10 and displayed fast uptake kinetics and excellent selectivity due to the 3D porous interconnected network and larger specific surface area. Importantly, the recycling process is easy, using only tweezers to directly move the 3D aerogel adsorbents from one reaction system to another. Therefore, the FL-δ-Bi2O3 aerogel may be a promising practical adsorbent for the selective capture of radioactive iodide.

  15. Separation of antimony(III) with iodide and dithizone by sorption on polyurethane foam from sulphuric acid medium for its spectrophotometric determination in glasses.

    Science.gov (United States)

    Raychaudhuri, A; Roy, S K

    1994-02-01

    A method for quantitative separation of antimony(III) by sorption on polyether based polyurethane foam and its spectrophotometric determination has been described. The method involves formation of a pink-red complex of antimony(III) with iodide (0.045M) and dithizone (2.3 x 10(-5)M) in 0.25-0.75M H(2)SO(4) medium, sorption of the complex on polyurethane foam (within 45 min) at room temperature followed by its elution with acidified acetone (acetone containing 0.008% H(2)SO(4)) and spectrophotometric measurement at 507.2 nm ( = 2.56 x 10(4) l mol cm). The method obeys Beer's law from 0.1 to 6.0 mug antimony(III). Tolerance limits of other ions are Co (100 mug), Ni (100 mug), Fe (10 mug), Cu (0.5 mug), Sn (20 mug), Zn (100 mug), As (100 mug), Mn (200 mug), Pb (50 mug), Ti (100 mug), V (50 mug), etc. Interference by iron and copper have been eliminated by treating with KOH prior to the extraction of antimony. The method has been standardized with glass samples spiked with known amounts of antimony and applied to the determination of antimony in various glasses.

  16. Ginkgo biloba extract alters the binding of the sodium [{sup 123}I] iodide (Na{sup 123}I) on blood constituents

    Energy Technology Data Exchange (ETDEWEB)

    Aleixo, Luiz Claudio Martins [Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, 28 de Setembro, 87, 20551-030, Rio de Janeiro, RJ (Brazil); Comissao Nacional de Energia Nuclear, Instituto de Engenharia Nuclear, Cidade Universitaria, Ilha do Fundao, Via Cinco s/n, 21945-450 Rio de Janeiro (Brazil); Moreno, Silvana Ramos Farias, E-mail: srfmoreno@hotmail.com [Departamento de Patologia, Universidade Federal Fluminense, 24030-210, Niteroi, RJ (Brazil); Programa de Pos-Graduacao em Ciencias Medicas, Universidade Federal Fluminense, 24030-210, Niteroi, RJ (Brazil); Freitas, Rosimeire de Souza [Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, 28 de Setembro, 87, 20551-030, Rio de Janeiro, RJ (Brazil); Thomaz, Helio [Comissao Nacional de Energia Nuclear, Instituto de Engenharia Nuclear, Cidade Universitaria, Ilha do Fundao, Via Cinco s/n, 21945-450 Rio de Janeiro (Brazil); Santos-Filho, Sebastiao David [Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, 28 de Setembro, 87, 20551-030, Rio de Janeiro, RJ (Brazil)

    2012-01-15

    We evaluated the in vitro effect of an aqueous extract of Ginkgo biloba (EGb) on the distribution in blood cells (BC) and plasma (P) and on the binding of Na{sup 123}I to the blood constituents using precipitation with trichloroacetic acid. The radioactivity percentages insoluble (SF) and insoluble fraction (IF) of blood constituents were determined. The EGb interfered (p<0.05) on the distribution of Na{sup 123}I in the P (from 69.64 to 86.13) and BC (from 30.36 to 13.87) and altered the fixation of the Na{sup 123}I in IF-P and in IF-BC. - Highlights: Black-Right-Pointing-Pointer Interaction between the Ginkgo biloba and blood constituents radiolabeled. Black-Right-Pointing-Pointer Modification of the binding of sodium iodide (Na{sup 123}I) to the blood constituents. Black-Right-Pointing-Pointer This alteration should have influence in a diagnosis of nuclear medicine.

  17. Particles Size and Conductivity Study of P-Type Copper (I) Iodide (CuI) Thin Film for Solid State Dye-Sensitized Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Zainun, A R; Mamat, M H; Noor, U M; Rusop, M, E-mail: ayib_rosdi@hotmail.com [Solar Cell Laboratory, Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia)

    2011-02-15

    Copper Iodide based dye-sensitized solar cells (DSSC) has been reported either deliver small photocurrents or highly unstable. In this research, by added in a small amount of Tetra-methyl-ethylene-diamine (TMED) into CuI sol-gel (CuI in acetonitrile), performance of electrical properties and optical properties of CuI based DSSC have been studied. Particles size and conductivity of CuI solution were measured when addition of TMED to the sol at 0.05M concentrations. Spin-coating technique has been explored to prepare nano-crystalline CuI films at room temperature. The film was examined for their surface morphology, optical and electrical properties by field emission scanning electron microscope (FESEM), ultraviolet visible spectroscopy (UV-Vis), Photoluminescence (PL) and current-voltage (I-V) measurement respectively. The results were then compared with CuI sol-gel which prepared by dissolving CuI powder with acetonitrile only. It showed some improvement to the CuI-based DSSC by incorporation of a small quantity of TMED in the solution of precursor.

  18. Preparation of Polyfunctional Organozinc Halides by an InX3 - and LiCl-Catalyzed Zinc Insertion to Aryl and Heteroaryl Iodides and Bromides.

    Science.gov (United States)

    Benischke, Andreas D; Le Corre, Grégoire; Knochel, Paul

    2017-01-18

    A catalytic system consisting of InCl3 (3 mol %) and LiCl (30 mol %) allows a convenient preparation of polyfunctional arylzinc halides via the insertion of zinc powder to various aryl iodides in THF at 50 °C in up to 95 % yield. The use of a THF/DMPU (1:1) mixture shortens the reaction rates and allows the preparation of keto-substituted arylzinc reagents. In the presence of In(acac)3 (3 mol %) and LiCl (150 mol %), the zinc insertion to various aryl and heteroaryl bromides proceeds smoothly (50 °C, 2-18 h). Alkyl bromides are also converted to the corresponding zinc reagents in the presence of In(acac)3 (10 mol %) and LiCl (150 mol %) in 70-80 % yield. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. 1-Butyl-3-methylimidazolium hexafluorophosphate ionic liquid as a new solvent for the determination of lead(II) and cadmium(II) by anodic stripping voltammetry after extraction of the iodide complexes.

    Science.gov (United States)

    Kamio, Akihiro; Nagaosa, Yukio

    2008-10-01

    The use of 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM x PF(6)) as a solvent for the anodic stripping analysis of Pb(II) and Cd(II) after extraction of the iodide complexes has been investigated. This method is based on the extraction of the metal iodide complexes into BMIM x PF(6), followed by differential-pulse anodic stripping voltammetry with an in-situ plated bismuth film electrode onto an edge-plane type of pyrolytic graphite substrate. When tetra-n-propylammonium iodide at a concentration of 0.20 mol L(-1) was used as an extractant and a supporting electrolyte, the reduced lead and cadmium produced well-defined anodic peaks at -414 and -736 mV vs. Ag/AgCl, respectively. The peak currents for Pb(II) and Cd(II) were directly proportional to the initial metal concentration in the ranges of 0.01-0.50 microg mL(-1) and 0.05-1.0 microg mL(-1) under the optimized conditions. A detection limit (S/N = 3) of 0.001 microg mL(-1) Pb(II) was obtained with a volume ratio (V(aq)/V(BMIM x PF(6))) of 2.0 at 300 s deposition time. The relative standard deviation was 3.2% on replicate runs (n = 10) for the determinations of 0.20 microg mL(-1) Pb(II).

  20. delta-Iodolactones decrease epidermal growth factor-induced proliferation and inositol-1,4,5-trisphosphate generation in porcine thyroid follicles--a possible mechanism of growth inhibition by iodide.

    Science.gov (United States)

    Dugrillon, A; Gärtner, R

    1995-06-01

    delta-Iodolactone (6-iodo-8,11,14-eicosatrienoic delta-lactone, delta-IL), an iodinated derivative of arachidonic acid, has been shown to be synthesized in thyroid tissue and to inhibit thyroid cell proliferation. It is discussed as a potential mediator of the autoregulatory pathway of iodide in cyclic adenosine-3',5'-monophosphate (cAMP)- and thyrotropin (TSH)-independent growth. We therefore further localized the action of iodide and of delta-IL in isolated porcine thyroid follicles. Epidermal growth factor (EGF) and 12-O-tetradecanoylphorbol-13-acetate (TPA) dose dependently stimulated thyroid cell proliferation, which could be inhibited by staurosporin (0.1-10 nmol/l). Iodide (2.5-40 mumol/l) as well as delta-IL (0.5-2 mumol/l) also dose dependently inhibited EGF- and TPA-induced proliferation. As the calcium ionophor A23187 (100 pmol/l) completely abolished the inhibitory effects of iodide and of delta-IL, this may indicate a mechanism of delta-IL at or proximal to the calcium-dependent activation of protein kinase C. The growth inhibitory effect was restricted to delta-iodolactones when delta-IL was compared to 6-iodo-8,11,14,17-eicosatetraenoic delta-lactone and 5-iodo-7,10,13,16,19-docosapentaenoic gamma-lactone. It could not be prevented with propylthiouracil and therefore deiodination and a different iodide action is unlikely. Inositol-1,4,5-trisphosphate (IP3) and cAMP were measured in extracts from isolated porcine thyroid follicles stimulated with EGF (10 ng/ml) or TSH (1.0 U/l) revealing comparable kinetics in IP3 generation, while cAMP formation was only stimulated by TSH. delta-Iodolactone (2 mumol/l) only decreased EGF-induced IP3 formation, whereas TSH-induced IP3 and cAMP formation was unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)