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Sample records for iodine adsorption dissociation

  1. Dissociation of molecular iodine in RF discharge for oxygen-iodine laser

    Czech Academy of Sciences Publication Activity Database

    Jirásek, Vít; Schmiedberger, Josef; Čenský, Miroslav; Kodymová, Jarmila

    2012-01-01

    Roč. 66, č. 4 (2012), 1-6 ISSN 1434-6060 R&D Projects: GA ČR GA202/09/0310 Grant - others:European Office for Aerospace R&D(XE) FA8655-09-1-3092 Institutional research plan: CEZ:AV0Z10100523 Keywords : molecular iodine * RF discharge * dissociation * oxygen-iodine laser * COIL Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.513, year: 2012

  2. Combined DFT and XPS investigation of iodine anions adsorption on the sulfur terminated (001) chalcopyrite surface

    Energy Technology Data Exchange (ETDEWEB)

    Li, Kui, E-mail: likui9606@stu.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Zhao, Yaolin, E-mail: zhaoyaolin@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Zhang, Peng, E-mail: zp32@qq.com [Sino Shaanxi Nuclear Industry Group, Xi’an 710100 (China); He, Chaohui, E-mail: hechaohui@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Deng, Jia, E-mail: djkokocase@stu.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Ding, Shujiang, E-mail: dingsj@mail.xjtu.edu.cn [Department of Applied Chemistry, School of Science, Xi’an Jiaotong University, Xi’an 710049 (China); Shi, Weiqun, E-mail: shiwq@ihep.ac.cn [Key Laboratory of Nuclear Radiation and Nuclear Energy Technology and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

    2016-12-30

    Highlights: • Metal surface sites of (001)-S surface of chalcopyrite show significant chemical affinity to iodide and iodate. • The energetically favorable active site is copper for iodide adsorption and iron for iodate adsorption, respectively. • Iodate undergoes a dissociative adsorption on the copper site of chalcopyrite surface. - Abstract: The adsorption of iodine anions (iodide and iodate) on the sulfur terminated (001) chalcopyrite surface has been systematically investigated combining first-principles calculations based on density functional theory (DFT) with X-ray photoelectron spectroscopy (XPS) measurements. Based on the total energy calculations and geometric optimization, the thermodynamically preferred site was copper atom for iodide adsorption and iron atom for iodate adsorption, respectively. In the case of Cu site mode, the iodate underwent a dissociative adsorption, where one I−O bond of iodate ion was broken and the dissociative oxygen atom adsorbed on the adjacent sulphur site. Projected density of states (PDOS) analysis further clarified the interaction mechanism between active sites of chalcopyrite surface and adsorbates. In addition, full-range XPS spectra qualitatively revealed the presence of iodine on chalcopyrite surface. High resolution XPS spectra of the I 3d peaks after adsorption verified the chemical environment of iodine. The binding energies of 618.8 eV and 623.5 eV for I 3d{sub 5/2} peaks unveiled that the adsorption of iodide and iodate ions on copper-iron sulfide minerals was the result of formation of low solubility metal iodides precipitate. Also two I 3d peaks with low intensity around 618 eV and 630 eV might be related to the inorganic reduction of iodate to iodide by reducing S{sup 2−} ion of chalcopyrite.

  3. Adsorption of iodine and cesium onto some cement materials

    Energy Technology Data Exchange (ETDEWEB)

    Mine, Tatsuya [Mitsui Shipbuilding and Engineering Co. Ltd., Tokyo (Japan); Mihara, Morihiro; Ito, Masaru [Power Reactor and Nuclear Fuel Development Corp., Tokai, Ibaraki (Japan). Tokai Works; Kato, Hiroshige [IDC, Tokai, Ibaraki (Japan)

    1997-06-01

    Cement materials, being expected to be used in structural materials in underground disposals of radioactive wastes, may adsorb nuclides resulting in retardation of their migration in environment. In this report adsorption behaviors of cement pastes toward iodine (as anion) and cesium (as cation) were studied. Adsorption of iodine was remarkable for OPC and MHP pastes that are known to have high molar ratio CaO/SiO{sub 2}, partition coefficient being 100 ml/g for initial tracer concentration of 10{sup -5} mol/l. Partition coefficient for cesium for PFA paste was found to be 5 ml/g on average. (S. Ohno)

  4. Ultrahigh iodine adsorption in porous organic frameworks

    KAUST Repository

    Pei, Cuiying

    2014-01-01

    We present two porous organic frameworks (POFs), PAF-1 and JUC-Z2, with ultrahigh iodine capture capacity. The iodine vapor uptake of PAF-1 and JUC-Z2 were 1.86 g g-1 and 1.44 g g-1 respectively at 298 K per 40 Pa, which is extremely high for such low pressure sorption conditions. In addition, PAF-1 and JUC-Z2 could adsorb iodine over water with the selectivity of 5.1 and 6.5 respectively. The isosteric enthalpy at zero surface coverage, calculated by a virial equation with the iodine vapor sorption isotherms at 298 K and 313 K of JUC-Z2, reached -51.1 kJ mol-1, which was much higher than the coverage of PAF-1 (-14.9 kJ mol-1). Raman measurement confirmed the polyiodide to be I5 - in POFs. Furthermore, solvents with different polarities, such as n-hexane, chloroform, and methanol, were chosen to conduct iodine binding measurements on PAF-1 and JUC-Z2. The formation constant Kf for POFs in n-hexane, chloroform and methanol drastically decreased with the increase in polarity, thus illustrating the important role of solvents in iodine binding. © the Partner Organisations 2014.

  5. Adsorption of Acetic Acid, Cadmium ions, Lead ions and Iodine ...

    African Journals Online (AJOL)

    Michael Horsfall

    Adsorption of Acetic Acid, Cadmium ions, Lead ions and Iodine Using Activated. Carbon from Waste Wood and Rice Husks. GOODHEAD, T O; DAGDE, K K. Department of Chemical/Petrochemical Engineering, Rivers State university of Science and Technology. Port Harcourt, Nigeria. ABSTRACT: This paper presents the ...

  6. Protein aggregation and degradation during iodine labeling and its consequences for protein adsorption to biomaterials

    DEFF Research Database (Denmark)

    Holmberg, Maria; Jensen, Karin Bagger Stibius; Ndoni, Sokol

    2007-01-01

    Protein adsorption on modified and unmodified polymer surfaces investigated through radiolabeling experiments showed a tendency for higher than expected albumin and immunoglobulin G (IgG) adsorption. Possible enhanced protein aggregation and degradation caused by the iodine labeling method used...

  7. Heterolytic dissociative adsorption state of dihydrogen favored by interfacial defects

    Science.gov (United States)

    Song, Zhenjun; Hu, Hanshi; Xu, Hu; Li, Yong; Cheng, Peng; Zhao, Bin

    2018-03-01

    The atomic-scale insight into dihydrogen on MgO(001) surface deposited on molybdenum substrate with interfacial defects was investigated in detail by employing density functional methods Here we report novel dissociative adsorption behaviors of single hydrogen molecule on the usually inert oxide surfaces, with consideration of two types of dissociation schemes. The heterolytic dissociation state -Mg(H)-O(H)- of dihydrogen is impossible to obtain on neighboring O-Mg sites of perfect bulk MgO(001) terraces. Unusually, the hydrogen molecule can form heterolytic fragmentation states on metal supported MgO(001) films with very low activation barrier (0.398 eV), and the heterolytic dissociation state is much more favorable than homolytic dissociation state both energetically and kinetically in all cases. Electronic properties and bonding attribution of adsorbates and the oxide-metal hybrid structure are revealed by analyzing density of states, differential charge densities, orbital interaction and electron localization function. The characteristic changes to the property and activity of magnesia (001) can have potential application in catalytic reactions.

  8. Dissociation kinetics of iodine in oxygen-containing electrical discharge plasmas

    International Nuclear Information System (INIS)

    Zakharov, A.I.; Klopovskii, K.S.; Rakhimova, T.V.; Samorodov, V.A.

    1993-01-01

    Studies of the kinetics of gaseous media containing oxygen and iodine molecules have been stimulated to a substantial degree by the search for ways of improving iodine-oxygen lasers and by the need for information on loss processes for atmospheric ozone. Results are presented from an experimental study and numerical simulations of the kinetics of the dissociation of iodine in self-sustained volume discharges in high-pressure O 2 :Ar:I 2 mixtures. It is shown that the well-studied mechanism for dissociation based on excitation of iodine molecules in successive collisions with singlet oxygen and excited iodine atoms is supplanted by a substantially different mechanism involving the creation and loss of 10 radicals when the densities of atomic oxygen and ozone are high enough. It is also shown that iodine fractions as low as ∼10 -3 in the mixture lead to rapid loss of ozone molecules while less than 18% of the discharge energy is expended in the production of singlet oxygen

  9. CO adsorption and dissociation on Pt(111) and Ni(111) surfaces

    DEFF Research Database (Denmark)

    Morikawa, Y.; Mortensen, Jens Jørgen; Hammer, Bjørk

    1997-01-01

    CO adsorption and dissociation processes have been studied using first-principles total energy and force calculations. The adsorption energies, atomic structures and vibrational modes of molecularly chemisorbed states are well reproduced in the present calculations. We have examined several...

  10. Iodine Gas Adsorption in Nanoporous Materials: A Combined Experiment–Modeling Study

    Energy Technology Data Exchange (ETDEWEB)

    Sava Gallis, Dorina F.; Ermanoski, Ivan; Greathouse, Jeffrey A.; Chapman, Karena W.; Nenoff, Tina M.

    2017-02-13

    Here, we present a combined experimental and Grand Canonical Monte Carlo (GCMC) modeling study on the adsorption of iodine in three classes of nanoporous materials: activated charcoals, zeolites, and metal–organic frameworks (MOFs). Iodine adsorption profiles were measured for the first time in situ, with a uniquely designed sorption apparatus. It was determined that pore size and pore environment are responsible for a dynamic adsorption profile, correlated with distinct pressure ranges. At pressures below 0.3 atm, iodine adsorption is governed by a combination of small pores and extra-framework components (e.g., Ag+ ions in the zeolite mordenite). At regimes above 0.3 atm, the amount of iodine gas stored relates with an increase in pore size and specific surface area. GCMC results validate the trends noted experimentally and in addition provide a measure of the strength of the adsorbate–adsorbent interactions in these materials.

  11. Iodine Adsorption by Ag-Aerogel under Prototypical Vessel Off-Gas Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-08-01

    U.S. regulations will require the removal of 129I from the off-gas streams of any used nuclear fuel (UNF) reprocessing plant prior to discharge of the off-gas to the environment. The required plant decontamination factor for iodine will vary based on fuel burnup, cooling time, and other factors but is very likely to be >1000 and could be as high as 8000. Multiple off-gas streams within a UNF reprocessing plant combine prior to environmental release, and each of these streams contains some amount of iodine. To achieve the decontamination factors (DFs) that are likely to be required by regulations, iodine removal from the vessel off-gas will be necessary. The vessel off-gas contains iodine at very dilute concentrations (ppb levels), and will also contain water vapor. Iodine species present are likely to include both elemental and organic iodides. There will also be solvent vapors and volatile radiolysis products. The United States has considered the use of silver-based sorbents for removal of iodine from UNF off-gas streams, but little is known about the behavior of those sorbents at very dilute iodine concentrations. The purpose of this study was to expose silver-functionalized silica aerogel (AgAerogel) to a prototypical vessel off-gas stream containing 40 ppb methyl iodide to obtain information about organic iodine capture by silver-sorbents at very low iodine concentrations. The design of this extended duration testing was such that information about the rate of adsorption, the penetration of the iodine species, and the overall system DF could be obtained. Results show that CH3I penetrates into a AgAerogel sorbent bed to a depth of 3.9 cm under prototypical vessel off-gas conditions. An iodine loading of 22 mg I/g AgAerogel was observed in the first 0.3 cm of the bed. Of the iodine delivered to the system, 48% could not be accounted for, and future efforts will investigate this concern. Direct calculation of the decontamination factor is not

  12. Iodine

    Science.gov (United States)

    ... Consumer Datos en español Health Professional Other Resources Iodine Fact Sheet for Consumers Have a question? Ask ... find out more about iodine? Disclaimer What is iodine and what does it do? Iodine is a ...

  13. X-ray Pump–Probe Investigation of Charge and Dissociation Dynamics in Methyl Iodine Molecule

    Directory of Open Access Journals (Sweden)

    Li Fang

    2017-05-01

    Full Text Available Molecular dynamics is of fundamental interest in natural science research. The capability of investigating molecular dynamics is one of the various motivations for ultrafast optics. We present our investigation of photoionization and nuclear dynamics in methyl iodine (CH3I molecule with an X-ray pump X-ray probe scheme. The pump–probe experiment was realized with a two-mirror X-ray split and delay apparatus. Time-of-flight mass spectra at various pump–probe delay times were recorded to obtain the time profile for the creation of high charge states via sequential ionization and for molecular dissociation. We observed high charge states of atomic iodine up to 29+, and visualized the evolution of creating these high atomic ion charge states, including their population suppression and enhancement as the arrival time of the second X-ray pulse was varied. We also show the evolution of the kinetics of the high charge states upon the timing of their creation during the ionization-dissociation coupled dynamics. We demonstrate the implementation of X-ray pump–probe methodology for investigating X-ray induced molecular dynamics with femtosecond temporal resolution. The results indicate the footprints of ionization that lead to high charge states, probing the long-range potential curves of the high charge states.

  14. Adsorption and revaporisation studies on iodine oxide aerosols deposited on containment surface materials in LWR

    Energy Technology Data Exchange (ETDEWEB)

    Tietze, S.; Foreman, M.R.StJ.; Ekberg, C. [Chalmers Univ. of Technology, Goeteborg (Sweden); Kaerkelae, T.; Auvinen, A.; Tapper, U.; Lamminmaeki, S.; Jokiniemi, J. [VTT Technical Research Centre of Finland, Espoo (Finland)

    2012-12-15

    During a hypothetical severe nuclear accident, the radiation field will be very high in the nuclear reactor containment building. As a result gaseous radiolysis products will be formed. Elemental iodine can react in the gaseous phase with ozone to form solid iodine oxide aerosol particles (iodine oxide). Within the AIAS (Adsorption of Iodine oxide Aerosols on Surfaces) project the interactions of iodine oxide (IOx) aerosols with common containment surface materials were investigated. Common surface materials in Swedish and Finnish LWRs are Teknopox Aqua V A paint films and metal surfaces such as Cu, Zn, Al and SS, as well as Pt and Pd surfaces from hydrogen recombiners. Non-radioactive and {sup 131}I labelled iodine oxide aerosols were produced with the EXSI CONT facility from elemental iodine and ozone at VTT Technical Research Centre of Finland. The iodine oxide deposits were analysed with microscopic and spectroscopic measurement techniques to identify the kind of iodine oxide formed and if a chemical conversion on the different surface materials occurs. The revaporisation behaviour of the deposited iodine oxide aerosol particles from the different surface materials was studied under the influence of heat, humidity and gamma irradiation at Chalmers University of Technology, Sweden. Studies on the effects of humidity were performed using the FOMICAG facility, while heat and irradiation experiments were performed in a thermostated heating block and with a gammacell 22 having a dose rate of 14 kGy/h. The revaporisation losses were measured using a HPGe detector. The revaporisated {sup 131}I species from the surfaces were chemically tested for elemental iodine formation. The parameter dominating the degradation of the produced iodine oxide aerosols was humidity. Cu and Zn surfaces were found to react with iodine from the iodine oxide aerosols to form iodides, while no metal iodides were detected for Al and SS samples. Most of the iodine oxide aerosols are assumed to

  15. Dynamics of production of iodine atoms by dissociation of iodides in a pulsed self-sustained discharge

    International Nuclear Information System (INIS)

    Vagin, Nikolai P; Kochetov, Igor' V; Napartovich, A P; Yuryshev, Nikolai N

    2013-01-01

    Absorption at the laser transition has been used for the first time to assess the evolution of concentration of iodine atoms in a pulsed self-sustained discharge in mixtures of iodides with a buffer gas such as molecular nitrogen and helium. Dynamics of the iodine atom production is studied by the method of absorption spectroscopy. The dissociation of C n F 2n+1 I and CnH 2n+1 I (n = 1, 2) iodides is investigated. The energy required to produce atomic iodine is evaluated. The experimental data obtained for CF 3 I are compared with the results of numerical simulations, their reasonable agreement being demonstrated. (active media)

  16. Organic Iodine Adsorption by AgZ under Prototypical Vessel Off-Gas Conditions

    International Nuclear Information System (INIS)

    Bruffey, Stephanie H.; Jubin, Robert Thomas; Jordan, J. A.

    2016-01-01

    U.S. regulations will require the removal of 129 I from the off-gas streams of any used nuclear fuel (UNF) reprocessing plant prior to discharge of the off-gas to the environment. Multiple off-gas streams within a UNF reprocessing plant combine prior to release, and each of these streams contains some amount of iodine. For an aqueous UNF reprocessing plant, these streams include the dissolver off-gas, the cell off-gas, the vessel off-gas (VOG), the waste off-gas and the shear off-gas. To achieve regulatory compliance, treatment of multiple off-gas streams within the plant must be performed. Preliminary studies have been completed on the adsorption of I 2 onto silver mordenite (AgZ) from prototypical VOG streams. The study reported that AgZ did adsorb I 2 from a prototypical VOG stream, but process upsets resulted in an uneven feed stream concentration. The experiments described in this document both improve the characterization of I 2 adsorption by AgZ from dilute gas streams and further extend it to include characterization of the adsorption of organic iodides (in the form of CH 3 I) onto AgZ under prototypical VOG conditions. The design of this extended duration testing was such that information about the rate of adsorption, the penetration of the iodine species, and the effect of sorbent aging on iodine removal in VOG conditions could be inferred.

  17. Automatic Method for Controlling the Iodine Adsorption Number in Carbon Black Oil Furnaces

    Directory of Open Access Journals (Sweden)

    Zečević, N.

    2008-12-01

    Full Text Available There are numerous of different inlet process factors in carbon black oil furnaces which must be continuously and automatically adjusted, due to stable quality of final product. The most important six inlet process factors in carbon black oil-furnaces are:1. volume flow of process air for combustion2. temperature of process air for combustion3. volume flow of natural gas for insurance the necessary heat for thermal reaction of conversionthe hydrocarbon oil feedstock in oil-furnace carbon black4. mass flow rate of hydrocarbon oil feedstock5. type and quantity of additive for adjustment the structure of oil-furnace carbon black6. quantity and position of the quench water for cooling the reaction of oil-furnace carbon black.The control of oil-furnace carbon black adsorption capacity is made with mass flow rate of hydrocarbon feedstock, which is the most important inlet process factor. Oil-furnace carbon black adsorption capacity in industrial process is determined with laboratory analyze of iodine adsorption number. It is shown continuously and automatically method for controlling iodine adsorption number in carbon black oil-furnaces to get as much as possible efficient control of adsorption capacity. In the proposed method it can be seen the correlation between qualitatively-quantitatively composition of the process tail gasses in the production of oil-furnace carbon black and relationship between air for combustion and hydrocarbon feedstock. It is shown that the ratio between air for combustion and hydrocarbon oil feedstock is depended of adsorption capacity summarized by iodine adsorption number, regarding to BMCI index of hydrocarbon oil feedstock.The mentioned correlation can be seen through the figures from 1. to 4. From the whole composition of the process tail gasses the best correlation for continuously and automatically control of iodine adsorption number is show the volume fraction of methane. The volume fraction of methane in the

  18. Iodine adsorption on ion-exchange resins and activated carbons: batch testing

    International Nuclear Information System (INIS)

    Parker, Kent E.; Golovich, Elizabeth C.; Wellman, Dawn M.

    2014-01-01

    Iodine sorption onto seven resins and six carbon materials was evaluated using water from well 299-W19-36 on the Hanford Site. These materials were tested using a range of solution-to-solid ratios. The test results are as follows. The efficacy of the resin and granular activated carbon materials was less than predicted based on manufacturers' performance data. It is hypothesized that this is due to the differences in speciation previously determined for Hanford groundwater. The sorption of iodine is affected by the iodine species in the source water. Iodine loading on resins using source water ranged from 1.47 to 1.70 µg/g with the corresponding K d values from 189.9 to 227.0 mL/g. The sorption values when the iodine is converted to iodide ranged from 2.75 to 5.90 µg/g with the corresponding K d values from 536.3 to 2979.6 mL/g. It is recommended that methods to convert iodine to iodide be investigated in fiscal year (FY) 2015. The chemicals used to convert iodine to iodate adversely affected the sorption of iodine onto the carbon materials. Using as-received source water, loading and K d values ranged from 1.47 to 1.70 µg/g and 189.8 to 226.3 mL/g respectively. After treatment, loading and K d values could not be calculated because there was little change between the initial and final iodine concentration. It is recommended the cause of the decrease in iodine sorption be investigated in FY15. In direct support of CH2M HILL Plateau Remediation Company, Pacific Northwest National Laboratory has evaluated samples from within the 200W pump and treat bioreactors. As part of this analysis, pictures taken within the bioreactor reveal a precipitate that, based on physical properties and known aqueous chemistry, is hypothesized to be iron pyrite or chalcopyrite, which could affect iodine adsorption. It is recommended these materials be tested at different solution-to-solid ratios in FY15 to determine their effect on iodine sorption.

  19. Iodine adsorption on ion-exchange resins and activated carbons: batch testing

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Kent E.; Golovich, Elizabeth C.; Wellman, Dawn M.

    2014-09-30

    Iodine sorption onto seven resins and six carbon materials was evaluated using water from well 299-W19-36 on the Hanford Site. These materials were tested using a range of solution-to-solid ratios. The test results are as follows. The efficacy of the resin and granular activated carbon materials was less than predicted based on manufacturers’ performance data. It is hypothesized that this is due to the differences in speciation previously determined for Hanford groundwater. The sorption of iodine is affected by the iodine species in the source water. Iodine loading on resins using source water ranged from 1.47 to 1.70 µg/g with the corresponding Kd values from 189.9 to 227.0 mL/g. The sorption values when the iodine is converted to iodide ranged from 2.75 to 5.90 µg/g with the corresponding Kd values from 536.3 to 2979.6 mL/g. It is recommended that methods to convert iodine to iodide be investigated in fiscal year (FY) 2015. The chemicals used to convert iodine to iodate adversely affected the sorption of iodine onto the carbon materials. Using as-received source water, loading and Kd values ranged from 1.47 to 1.70 µg/g and 189.8 to 226.3 mL/g respectively. After treatment, loading and Kd values could not be calculated because there was little change between the initial and final iodine concentration. It is recommended the cause of the decrease in iodine sorption be investigated in FY15. In direct support of CH2M HILL Plateau Remediation Company, Pacific Northwest National Laboratory has evaluated samples from within the 200W pump and treat bioreactors. As part of this analysis, pictures taken within the bioreactor reveal a precipitate that, based on physical properties and known aqueous chemistry, is hypothesized to be iron pyrite or chalcopyrite, which could affect iodine adsorption. It is recommended these materials be tested at different solution-to-solid ratios in FY15 to determine their effect on iodine

  20. X-ray photoelectron and Auger electron spectroscopic study of the adsorption of molecular iodine on uranium metal and uranium dioxide

    International Nuclear Information System (INIS)

    Dillard, J.G.; Moers, H.; Klewe-Nebenius, H.; Kirch, G.; Pfennig, G.; Ache, H.J.

    1984-01-01

    The adsorption of molecular iodine on uranium metal and on uranium dioxide has been investigated at 25 0 C. Clean surfaces were prepared in an ultrahigh vacuum apparatus and were characterized by X-ray photoelectron (XPS) and X-ray and electron-induced Auger electron spectroscopies (AES). Adsorption of I 2 was studied for exposures up to 100 langmuirs (1 langmuir = 10 -6 torr s) on uranium metal and to 75 langmuirs on uranium dioxide. Above about 2-langmuir I 2 exposure on uranium, spectroscopic evidence is obtained to indicate the beginning of UI 3 formation. Saturation coverage for I 2 adsorption on uranium dioxide occurs at approximately 10-15 langmuirs. Analysis of the XPS and AES results as well as studies of spectra as a function of temperature lead to the conclusions that a dissociative chemisorption/reaction process occurs on uranium metal while nondissociative adsorption occurs on uranium dioxide. Variations in the iodine Auger kinetic energy and in the Auger parameter are interpreted in light of extra-atomic relaxation processes. 42 references, 10 figures, 1 table

  1. Adsorption modes of molecular iodine on defected boron nitrides: A DFT study

    Science.gov (United States)

    Arabieh, Masoud; Azar, Yavar Taghipour

    2018-03-01

    The interaction of molecular iodine with pristine and monovacant boron-nitride quantum dots (QDs) have been investigated using density functional theory. It was found that removing one B or N single atom significantly decreased the calculated Eg values at various exchange functional. In B-defected BN system, the localized spin densities canceled each other and overall polarization of system was found to be equal to unity. For N-defected system there was smaller spin densities localized on each closest B atoms. Both B- and N-vacancies caused appearance of new states in gap region. Our calculation revealed that spin density and polarization of defected system are localized on vacancy region and other atoms did not take part in this polarization. The results of electron localization function for N-DBN showed there was high density region at the position of removed nitrogen atom. The calculated adsorption energies implied that there was no significant chemical interaction between iodine molecule and pristine BN sheet. We suggested that when a deficiency was imposed to the BN sheet, the reactivity of the modified system toward iodine molecule significantly could increase. We found strong interaction between iodine and nitrogen atoms of B-DBN system. In the case of I2/N-DBN system the neighbor atoms had no contribution in spin polarization of the system and it seemed that all spin density of system transferred to the iodine molecule after adsorption. Strong correlation between molecular iodine orientation and BN-QDs via their interactions type has been clarified in this work. These findings may provide a deeper insight into halogen molecules interactions with low dimensional defected boron nitrides.

  2. Adsorption and dissociation of dinitrogen on transition metal (Ta, W and Re) doped MgO surface

    KAUST Repository

    Yadav, Manoj Kumar

    2016-06-16

    The adsorption and dissociation of dinitrogen on transition metal (Ta, W and Re) doped MgO(100) surface has been studied employing density functional theory. It is found that all these transition metals (TM) on MgO(100) surface are capable of adsorbing dinitrogen (N2), however there is no dissociative adsorption of N2 on single transition metal dopant. When two TM atoms are doped on MgO(100) surface, dissociative adsorption of dinitrogen occurs in all the three cases. Whether the dissociation is spontaneous or is it associated with activation barrier depends on the orientation of N2 molecule approaching the dopant site.

  3. Iodine

    Science.gov (United States)

    ... in the ocean, where it is concentrated by sea life, especially seaweed. The thyroid gland needs iodine ... most recognized form of deficiency is goiter. Additionally, across the globe iodine deficiency is thought to be ...

  4. Density function theory study of the adsorption and dissociation of carbon monoxide on tungsten nanoparticles.

    Science.gov (United States)

    Weng, Meng-Hsiung; Ju, Shin-Pon; Chen, Hsin-Tsung; Chen, Hui-Lung; Lu, Jian-Ming; Lin, Ken-Huang; Lin, Jenn-Sen; Hsieh, Jin-Yuan; Yang, Hsi-Wen

    2013-02-01

    The adsorption and dissociation properties of carbon monoxide (CO) molecule on tungsten W(n) (n = 10-15) nanoparticles have been investigated by density-functional theory (DFT) calculations. The lowest-energy structures for W(n) (n = 10-15) nanoparticles are found by the basin-hopping method and big-bang method with the modified tight-binding many-body potential. We calculated the corresponding adsorption energies, C-O bond lengths and dissociation barriers for adsorption of CO on nanoparticles. The electronic properties of CO on nanoparticles are studied by the analysis of density of state and charge density. The characteristic of CO on W(n) nanoparticles are also compared with that of W bulk.

  5. Water adsorption and dissociation on the PuO2(1 1 0) surface

    International Nuclear Information System (INIS)

    Jomard, Gérald; Bottin, François; Geneste, Grégory

    2014-01-01

    Adsorption of the H 2 O molecule on the PuO 2 (1 1 0) surface is studied by density-functional calculations. The strong electronic correlations in the PuO 2 compound are treated in the DFT+U (Hubbard) formalism. A dissociated state of water is identified, resulting in the formation of hydroxyl groups and corresponding to a very exothermic process. However, a non-dissociated (molecular) form does exist as a metastable state. The Infra-Red and XPS signature of both forms are identified and compared to experiments. Kinetic Monte Carlo simulations show that adsorbed molecular water might have a long life-time before dissociating at low temperature, due to a small energy barrier between the molecular and dissociated configurations, in agreement with experiments

  6. Size effect on the adsorption and dissociation of CO{sub 2} on Co nanoclusters

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Haiyan; Cao, Dapeng; Fisher, Adrian [International Research Center for Soft Matter, State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Johnston, Roy L. [School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom); Cheng, Daojian, E-mail: chengdj@mail.buct.edu.cn [International Research Center for Soft Matter, State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China)

    2017-02-28

    Highlights: • Co{sub 13}, Co{sub 38} and Co{sub 55} nanoclusters were predicted as the high-symmetry structures. • CO{sub 2} dissociation on the size-selected Co{sub 13}, Co{sub 38} and Co{sub 55} nanoclusters was studied. • Co{sub 55} nanocluster possesses the highest activity relevant to CO{sub 2} dissociation. • A non-monotonous behavior of the dissociation barrier of CO{sub 2} with the size was found. - Abstract: Spin-polarized density functional theory calculations were carried out to study the adsorption and dissociation properties of CO{sub 2} on size-selected Co{sub 13}, Co{sub 38} and Co{sub 55} nanoclusters. Based on genetic algorithm method, Co{sub 13}, Co{sub 38} and Co{sub 55} nanoclusters were predicted as the most stable high-symmetry structures among these Co{sub n} (n = 2–58) nanoclusters from the Gupta potential. For the adsorption of CO{sub 2}, CO and O on size-selected Co{sub 13}, Co{sub 38} and Co{sub 55} nanoclusters, the lowest adsorption strength is found for all the different adsorbates on Co{sub 55} nanocluster. For the dissociation of CO{sub 2} on these size-selected Co nanoclusters, the largest Co{sub 55} nanocluster possesses the greatest catalytic activity for the dissociation of CO{sub 2}, with the smallest reaction barrier of 0.38 eV. Our results reveal a non-monotonous behavior of the catalytic activities of Co nanoclusters on size, which is of fundamental interest for the design of new Co catalysts for the conversion of CO{sub 2}.

  7. The adsorption and dissociation of water molecule on goethite (010) surface: A DFT approach

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Long, E-mail: shuweixia@ouc.edu.cn [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, College of Chemistry and Chemical Engineering (China); Xiu, Fangyuan [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, College of Chemistry and Chemical Engineering (China); Qiu, Meng [Qingdao Institute of Bioenergy and Bioprocess Technology (China); Xia, Shuwei; Yu, Liangmin [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, College of Chemistry and Chemical Engineering (China)

    2017-01-15

    Graphical abstract: The optimized structure of hydrated goethite (010) surface with medium water coverage (water density about 6.7 H{sub 2}O/nm{sup 2}). - Highlights: • Stable adsorption and dissociation structure of H{sub 2}O on goethite (010) surface was investigated by DFT. • Reasonable path for water dissociation was proposed by transitional state analysis. • The mechanism of water adsorption on goethite and binding nature were revealed by PDOS. - Abstract: Using density functional theory (DFT) calculation, we investigate the configuration, stability and electronic properties of fresh cleaved (010) goethite surface (Pnma) and this surface exposed to water monolayer at low, medium and high coverage. Water is predicted to be chemisorbed to the surface, together with the surface reconstruction. The interaction energy of the most stable configuration of both low and medium coverage per water molecule is almost the same (−1.17 eV), while that of high coverage is much lower (less than 1.03 eV). It indicates that highly hydrated surface is less stable. PDOS analysis reveals the adsorption of H{sub 2}O is due to the formation of Fe−O bond, caused by overlapping of Fe's 3d and O's 2p orbitals. Dissociation processes at low and medium water coverage are non-spontaneous; while at high coverage, it can undertake spontaneously both thermodynamically and dynamically. The dissociation paths of all three water coverage are the similar. The proton from one adsorbed water is likely to dissociate to bind to the vicinal surface μ{sub 3}−O as an intermediate product; the proton belonged to μ{sub 3}−O transferred to the neighbor surface μ{sub 2}−O as the dissociative configuration.

  8. The dissociative adsorption of hydrogen: Two-, three-, and four-dimensional quantum simulations

    DEFF Research Database (Denmark)

    Nielsen, Ulrik; Halstead, David; Holloway, Stephen

    1990-01-01

    A quantum wave packet calculation for the activated dissociative adsorption of H2 is presented. Restricting the motion of the molecule to lie within a plane normal to the surface we have treated all four molecular degrees of freedom exactly. We compare results obtained using two-, three-, and four...... and diffraction on an equal footing. By including a rotational degree of freedom, it is seen that strong orientational effects occur near to the transition state and result in an anisotropic selectivity in the dissociation. By examining the state-to-state scattering probabilities, it is possible to use...

  9. Ag{sup II} doped MIL-101 and its adsorption of iodine with high speed in solution

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Ping; Qi, Bingbing; Liu, Ying [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Zhao, Lei [Lianyungang Institute of Nanjing University of Science and Technology, Lianyungang 222006 (China); Jiao, Yan [Jiangsu Engineering Technology Research Center of Environmental Cleaning Materials (CEM), School of Environmental Sciences and Engineering, Nanjing University of Information Science and Technology (China); Zhang, Yi; Jiang, Zheng; Li, Qiang [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Wang, Jinfeng [Nanjing Chemical Industries Co., Ltd., SINOPEC, Nanjing 210048 (China); Chen, Shouwen [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Yang, Yi, E-mail: yyi301@163.com [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2016-05-15

    In order to improve the adsorption speed of iodine from water, MIL-101 with extra-large specific surface area (3054 m{sup 2}/g) was chosen as a base material, and then, Ag was doped into MIL-101 to enhance its adsorption capacity through an incipient-wetness impregnation method. With the characterization of SEM-EDS, TEM, XRD, XPS, TGA, IR, and BET techniques, the resulting Ag was identified to be stay in the framework of MIL-101 stably in the form of Ag{sup II} (generally, Ag{sup II} cation is not stable). However, after the adsorption of I{sup −} anions, Ag{sup II} stay in the cages of MIL-101 in the form of AgI/AgI{sub 3}. It is important to note that, all adsorbents show high adsorption speed of iodine in solution. The equilibrium adsorption time of the adsorbents were acquired by only a few minutes, which can be attributed to its large BET surface area. An interesting note is that, when the doping amount of Ag is less than 9%, the iodine anions adsorption capacity of Ag@MIL-101 is greater than its theoretical adsorption capacity. It shows that both physical adsorption and chemical adsorption are existed in the adsorption process. This study hopefully leads to a new and highly efficient Ag-based adsorbent for iodide adsorb from solutions. - Graphical abstract: Ag{sup II} stay in the framework of MIL-101 stably because of F{sup -}, after the adsorption of I{sup -} anions, Ag{sup I}I /Ag{sup I}I{sub 3} stay in the cages of MIL-101. The equilibrium adsorption time of Ag@MIL-101 were acquired by only a few minutes. - Highlights: • Ag{sup II} was doped into MIL-101 by an incipient-wetness impregnation method. • Both physical adsorption and chemical adsorption are verified in the adsorption process. • Ag@MIL-101 exhibits high adsorption speed and adsorption capacity. • Ag@MIL-101 can be effectively applied to the removal of radioactive iodide anions from water in acidic and neutral medium.

  10. Study of the adsorption of methyl iodide and molecular iodine on clean uranium and uranium dioxide surfaces by means of X-ray photoelectron (XPS) and Auger electron spectroscopy (AES)

    International Nuclear Information System (INIS)

    Dillard, J.G.; Moers, H.; Klewe-Nebenius, H.; Kirch, G.; Pfennig, G.; Ache, H.J.

    1984-03-01

    The adsorption of methyl iodide as well as of molecular iodine on uranium metal and on uranium dioxide has been studied at 25 0 C. Surfaces of the substrates were cleaned and characterized before and after exposure using X-ray photoelectron (XPS) and X-ray and electron induced Auger electron (AES) spectroscopy. Exposures amounted up to 1500 L CH 3 I on uranium metal, 1000 L CH 3 I on UO 2 , 100 L I 2 on uranium metal, and 75 L I 2 on UO 2 (1 L = 1 Langmuir = 10 -6 torr x sec). From the measured binding energies, Auger parameters, and intensity ratios for substrate and adsorbate constituents we deduced that for both CH 3 I and I 2 on uranium metal a uranium iodide, UI 3 , is formed. The adsorption of CH 3 I on U-metal is in addition accompanied by the formation of a carbide-type carbon, UC. Thus, in both cases a dissociative (adsorption/reaction) process is observed. For adsorption of CH 3 I on UO 2 the experimental findings indicate a dissociative process, too, though the species formed could not be identified. In contrast, I 2 adsorption on UO 2 appears to have non-dissociative character. Saturation coverages for CH 3 I were found to be approx.= 2 L on U-metal and approx.= 5 L on UO 2 , for I 2 approx.= 40 L on U-metal and 10-15 L on UO 2 . Variations in the iodine Auger kinetic energy and in the Auger parameter are interpreted in light of extraatomic relaxation processes. (orig.) [de

  11. Adsorption and dissociation of oxygen molecules on Si(111)-(7×7) surface

    International Nuclear Information System (INIS)

    Niu, Chun-Yao; Wang, Jian-Tao

    2013-01-01

    The adsorption and dissociation of O 2 molecules on Si(111)-(7×7) surface have been studied by first-principles calculations. Our results show that all the O 2 molecular species adsorbed on Si(111)-(7×7) surface are unstable and dissociate into atomic species with a small energy barrier about 0.1 eV. The single O 2 molecule adsorption tends to form an ins×2 or a new metastable ins×2* structure on the Si adatom sites and the further coming O 2 molecules adsorb on those structures to produce an ad-ins×3 structure. The ad-ins×3 structure is indeed highly stable and kinetically limited for diving into the subsurface layer to form the ins×3-tri structure by a large barrier of 1.3 eV. Unlike the previous views, we find that all the ad-ins, ins×2, and ad-ins×3 structures show bright images, while the ins×2*, ins×3, and ins×3-tri structures show dark images. The proposed oxidation pathways and simulated scanning tunneling microscope images account well for the experimental results and resolve the long-standing confusion and issue about the adsorption and reaction of O 2 molecules on Si(111) surface

  12. Carbon disulfide (CS{sub 2}) adsorption and dissociation on the Cu(100) surface: A quantum chemical study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wenju, E-mail: wangwenju1982@163.com; Fan, Lili; Wang, Guoping, E-mail: wgp1976@163.com

    2017-08-31

    Highlights: • CS{sub 2}, CS, C and S are strongly chemadsorbed on the Cu(100) surface. • C/S/S, S/CS and CS{sub 2} accord to a decreased adsorption strength on the Cu(100). • The asymmetric model CS{sub 2}(II) is easier to dissociate on the Cu(100) surface. - Abstract: Density functional theory (DFT) is used to examine the adsorption and dissociation of CS{sub 2} on the Cu(100) surface. This study evaluates the adsorption energies and geometries of the species (CS{sub 2}, CS, C and S) adsorption on the Cu(100) surface, as well as that coadsorption of CS and a S atom, and that coadsorption of C atom and two S atoms. The results indicate that the species (CS{sub 2}, CS, C and S) are strongly chemadsorbed on the Cu(100) surface through the C−Cu and/or S−Cu bond with an increased adsorption energy (C/S/S > S/CS > CS{sub 2}). Two pathways for CS{sub 2} dissociation on the Cu(100) surface are constructed, and the energy barrier and reaction energy of each step are calculated. It shows that the dissociated energy barrier of the second C−S bond is 0.25 eV higher than that of the first C−S bond in the pathway 1, but in the pathway 2, the dissociated energy barrier of the second C−S bond is 0.11 eV lower than that of the first C−S bond. Comparing the highest dissociated energy barrier of pathway 1 (0.68 eV) and pathway 2 (0.5 eV), the structure of S/C/S(II) is regarded as a preferable product for the dissociation of CS{sub 2} on the Cu(100) surface.

  13. H2S adsorption and dissociation on NH-decorated graphene: A first principles study

    Science.gov (United States)

    Faye, Omar; Eduok, Ubong; Szpunar, Jerzy; Samoura, Almoustapha; Beye, Aboubaker

    2018-02-01

    The removal of H2S gas poses an emerging environmental concern because of the lack of knowledge of an efficient adsorbent. A detailed theoretical study of H2S adsorption and dissociation on NH-doped graphene (GNH) has been carried out by means of density theory calculations. Our results reveal that the adsorption of H2S molecule on GNH composite is enhanced by the presence of active site such as the NH radicals. These NH radical sites formed NHsbnd H bonds and increase the charge transfer from H2S to GNH. The dissociation of the adsorbed H2S molecule leads the chemisorption of SH radical via H-transfer to GNH, while the formation of GNH2 at a weight percent of 3.76 wt% of NH radical is an endothermic process with an energy of 0.299 eV and 0.358 eV for ortho and para-position respectively. However, at 7.25 wt% NH radical, we observed a complete dissociation of H2S molecule with an energy released of 0.711 eV for the chemisorbed S atom on GN2H4. Moreover, the H-transfer of the second H atom of H2S molecule at 3.76 wt% was energetic unfavorable. The trend of predicted results within this study reveals that NH-doped graphene (GNH) successfully adsorbed and eliminated of H2S molecule; this work unveils definitive theoretical procedures which can be tested and validated experimentally.

  14. Theoretical investigation on the adsorption and dissociation behaviors of TiCl4 on pyrolytic carbon surface

    Science.gov (United States)

    Jin, Na; Yang, Yanqing; Luo, Xian; Liu, Shuai; Li, Pengtao

    2018-01-01

    We present a theoretical investigation of the reaction mechanism of TiCl4 dissociation on pyrolytic carbon surface and discuss the influence of H atom on adsorption and dissociation behaviors of TiCl4 by using density functional theory. The adsorption behaviors of TiClx (x = 4-0) and the interactions between pre-adsorbed H atom and TiClx are studied by calculating adsorption energies Eads and interaction energies HTi, respectively. The pre-adsorbed H atom significantly facilitates the adsorption of TiClx on pyrolytic carbon surface. Specially, TiCl3 adsorption on pyrolytic carbon surface converts from an endothermic process into an exothermic process due to the present of pre-adsorbed H atom. The calculation results of HTi show that the interactions between pre-adsorbed H atom and TiClx are attractive. The dissociation of TiCl4 on pre-adsorbed H pyrolytic carbon surface is an exothermic process, and TiCl4 → TiCl3 is the limited step. The dissociation barriers of each step are less than 1.5 eV except for TiCl → Ti, which does not need to overcome any barriers, that is to say, once TiCl is adsorbed on pre-adsorbed H surface the reaction of TiCl → Ti spontaneously occurs. It thus can be concluded that the dissociation of TiCl4 on pyrolytic carbon surface is a favorable process as long as H2 molecular have decomposed into atomic H and adsorbed on pyrolytic carbon surface, and the intermediate species (TiCl3, TiCl2 and TiCl) play an important role on the titanium CVD deposition. We also study the adsorption behavior of H atom and the dissociation behavior of H2 molecular on pyrolytic carbon surface.

  15. CO adsorption, dissociation and coupling formation mechanisms on Fe2C(001) surface

    Science.gov (United States)

    Yu, Xiaohu; Zhang, Xuemei; Meng, Yan; Zhao, Yaoping; Li, Yuan; Xu, Wei; Liu, Zhong

    2018-03-01

    By means of density functional theory calculations and atomic thermodynamics, we systematically investigated the CO adsorption on the Fe2C(001) surface at different coverage. It has been found that CO prefers to adsorb on the surface iron atom at low coverage (1-8 CO); CO prefers to adsorb at the bridge site of Fe and C atoms at high coverage (9-12 CO). Eight CO molecules binding on the Fe2C(001) surface is favorable thermodynamically as indicated by the stepwise adsorption energy. The phase diagram shows that addition of more CO molecules up to a number of 8 is thermodynamically favorable, and that the incremental energy gained by adding one more CO molecule is almost constant up to 4 CO molecules, decreases up to 8 CO molecules, after which it becomes thermodynamically unfavorable to add more CO molecules. Probability distribution of different singe-CO adsorbed states on the Fe2C(001) surface as function of temperature shows that CO dissociation and coupling are least preferred, indicating that carbide mechanism is not dominant in the iron-based Fischer-Tropsch synthesis reaction. The projected density of states (PDOS) was used to analyze the CO adsorption mechanism.

  16. Water Adsorption and Dissociation on Ceria-Supported Single-Atom Catalysts: A First-Principles DFT+U Investigation.

    Science.gov (United States)

    Han, Zhong-Kang; Gao, Yi

    2016-02-01

    Single-atom catalysts have attracted wide attention owing to their extremely high atom efficiency and activities. In this paper, we applied density functional theory with the inclusion of the on-site Coulomb interaction (DFT+U) to investigate water adsorption and dissociation on clean CeO 2 (111) surfaces and single transition metal atoms (STMAs) adsorbed on the CeO 2 (111) surface. It is found that the most stable water configuration is molecular adsorption on the clean CeO 2 (111) surface and dissociative adsorption on STMA/CeO 2 (111) surfaces, respectively. In addition, our results indicate that the more the electrons that transfer from STMA to the ceria substrate, the stronger the binding energies between the STMA and ceria surfaces. A linear relationship is identified between the water dissociation barriers and the d band centers of STMA, known as the generalized Brønsted-Evans-Polanyi principle. By combining the oxygen spillovers, single-atom dispersion stabilities, and water dissociation barriers, Zn, Cr, and V are identified as potential candidates for the future design of ceria-supported single-atom catalysts for reactions in which the dissociation of water plays an important role, such as the water-gas shift reaction. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. The reaction rate for dissociative adsorption of N-2 on stepped Ru(0001): Six-dimensional quantum calculations

    DEFF Research Database (Denmark)

    van Harrevelt, Rob; Honkala, Johanna Karoliina; Nørskov, Jens Kehlet

    2005-01-01

    Quantum-mechanical calculations of the reaction rate for dissociative adsorption of N-2 on stepped Ru(0001) are presented. Converged six-dimensional quantum calculations for this heavy-atom reaction have been performed using the multiconfiguration time-dependent Hartree method. A potential...

  18. Adsorption and dissociation of O2on MoO2(1[combining macron]11) surfaces: a DFT study.

    Science.gov (United States)

    Zhang, Quan; Zhang, Minhua; Wiltowski, Tomasz

    2017-11-08

    The adsorption and dissociation of O 2 on MoO 2 (1[combining macron]11) surfaces were studied by density functional theory (DFT). The results show that O 2 molecules prefer to be adsorbed on the five-coordinated Mo top sites. Density of states analysis shows strong hybridization of Mo 4d orbitals and O 2p orbitals in the Mo-O bond. Clean MoO 2 slabs and slabs with O 2 adsorption are metallic conductors, whereas the surface with high O atom coverage is reconstructed and becomes a semiconductor. Surface Mo atoms without adsorbed O or O 2 are spin-polarized. The oxygen adsorption shows the ability to reduce the spin of surface Mo atoms. The adsorption energy of the O 2 and O atoms decreases as coverage increases. The transition states of O 2 dissociation were located. The energy barriers for O 2 dissociation on the five-coordinated and four-coordinated Mo top sites are 0.227 eV and 0.281 eV, respectively.

  19. Adsorption and dissociation of H2O on Al(1 1 1) surface by density functional theory calculation

    International Nuclear Information System (INIS)

    Guo, F.Y.; Long, C.G.; Zhang, J.; Zhang, Z.; Liu, C.H.; Yu, K.

    2015-01-01

    Highlights: • O 2 on Al(1 1 1) surface can spontaneously dissociate, but H 2 O can not. • H 2 O, OH and H on top sites are favorable on Al(1 1 1) surface. • O on the hollow (fcc) site is preferred. • O which plays a key role in the dissociate reaction of H 2 O. - Abstract: Using the first-principles calculations method based on the density functional theory, we systematically study the adsorption behavior of a single molecular H 2 O on a clean and a pre-adsorbed O atom Al(1 1 1) surface, and also its corresponding dissociation reactions. The equilibrium configuration on top, bridge, and hollow (fcc and hcp) site were determined by relaxation of the system relaxation. The adsorptions of H 2 O, OH and H on top sites are favorable on the Al(1 1 1) surface, while that of O on the hollow (fcc) site is preferred. The results show that the hydrogen atom dissociating from H 2 O needs a 248.32 kJ/mol of energy on clean Al(1 1 1) surface, while the dissociating energy decreases to 128.53 kJ/mol with the aid of the O absorption. On the other hand, these phenomena indicate that the dehydrogenated reaction energy barrier of the pre-adsorbed O on metal surface is lower than that of on a clean one, because O can promote the dehydrogenation of H 2 O

  20. Adsorption and revaporisation studies of thin iodine oxide and CsI aerosol deposits from containment surface materials in LWRs

    Energy Technology Data Exchange (ETDEWEB)

    Tietze, S.; Foreman, M.; Ekberg, C. [Chalmers Univ. of Technology, Goeteborg (Sweden); Kaerkelae, T.; Auvinen, A.; Tapper, U.; Jokiniemi, J. [VTT Technical Research Centre of Finland, Espoo (Finland)

    2013-07-15

    During a severe nuclear accident released fission and radiolysis products can react with each other to form new species which might contribute to the volatile source term. Iodine will be released from UO2 fuel mainly in form as CsI aerosol particles and elemental iodine. Elemental iodine can react in gaseous phase with ozone to form solid iodine oxide aerosol particles (IOx). Within the AIAS-2 (Adsorption of Iodine Aerosols on Surfaces) project the interactions of IOx and CsI aerosols with common containment surface materials was investigated. Common surface materials in Swedish and Finnish LWRs are Teknopox Aqua V A paint films and metal surfaces such as Cu, Zn, Al and SS. Non-radioactive and {sup 131}I labelled aerosols were produced from a KI solution and ozone with a new facility designed and built at VTT Technical Research Centre of Finland. CsI aerosols were produced from a CsI solution with the same facility. A monolayer of the aerosols was deposited on the surfaces. The deposits were analysed with microscopic and spectroscopic measurement techniques to identify the chemical form of the deposits on the surfaces to identify if a chemical conversion on the different surface materials had occured. The revaporisation behaviour of the deposited aerosol particles from the different surface materials was studied under the influence of heat, humidity and gamma irradiation at Chalmers University of Technology, Sweden. Studies on the effects of humidity were performed using the FOMICAG facility, while heat and irradiation experiments were performed in a thermostated heating block and with a gammacell 22 with a dose rate of 14 kGy/h. The revaporisation losses were measured using a HPGe detector. The decomposition effect of the radiolysis product carbon monoxide was tested on IOx aerosols deposited on a glass fibre filter. Iodine oxide particles were produced at 50 deg. C, 100 deg. C and 120 deg. C and deposited on filter samples in order to study the chemical

  1. In-situ NAP XPS studies of dissociative water adsorption on GaAs(100) surfaces

    Science.gov (United States)

    Ptasinska, Sylwia; Zhang, Xueqiang

    2014-03-01

    In current semiconductor-based technology it is important to design and fabricate new materials in order to achieve specific well-defined properties and functionalities. Before such systems can be applied they first need to be understood, refined and controlled. Therefore, a basic knowledge about molecule/semiconductor surface interfaces is essential. In the present work dissociative water adsorption on the GaAs(100) surface is monitored using X-ray Photoelectron Spectroscopy (XPS) performed in situ under near ambient conditions. Firstly, the crystal surface is exposed to water vapor pressures ranging from UHV to 0.5 kPa. At elevated pressures an increase of oxygenation and hydroxylation of Ga surface atoms has been observed in the Ga2p XPS spectra. Moreover, intense signals obtained from molecularly adsorbed water molecules or water molecules adsorbed via hydrogen bond to surface OH groups have been also observed in the O1s spectra. Finally, the crystal surface is annealed up to 700 K at water vapor pressure of 0.01 kPa, which leads to desorption of physisorbed water molecules and further increase of surface oxidation. The research described herein was supported by the Division of Chemical Sciences, Geosciences and Biosciences, Basic Energy Sciences, Office of Science, United States Department of Energy through grant number DE-FC02-04ER15533.

  2. Dissociation coefficients of protein adsorption to nanoparticles as quantitative metrics for description of the protein corona: A comparison of experimental techniques and methodological relevance

    KAUST Repository

    Hühn, Jonas

    2015-12-31

    Protein adsorption to nanoparticles is described as a chemical reaction in which proteins attach to binding sites on the nanoparticle surface. This process can be described with a dissociation coefficient, which tells how many proteins are adsorbed per nanoparticle in dependence of the protein concentration. Different techniques to experimentally determine dissociation coefficients of protein adsorption to nanoparticles are reviewed. Results of more than 130 experiments in which dissociation coefficients have been determined are compared. Data show that different methods, nanoparticle systems, and proteins can lead to significantly different dissociation coefficients. However, we observed a clear tendency of smaller dissociation coefficients upon less negative towards more positive zeta potentials of the nanoparticles. The zeta potential thus is a key parameter influencing protein adsorption to the surface of nanoparticles. Our analysis highlights the importance of the characterization of the parameters governing protein-nanoparticle interaction for quantitative evaluation and objective literature comparison.

  3. Free energy landscape of dissociative adsorption of methane on ideal and defected graphene from ab initio simulations

    Science.gov (United States)

    Wlazło, M.; Majewski, J. A.

    2018-03-01

    We study the dissociative adsorption of methane at the surface of graphene. Free energy profiles, which include activation energies for different steps of the reaction, are computed from constrained ab initio molecular dynamics. At 300 K, the reaction barriers are much lower than experimental bond dissociation energies of gaseous methane, strongly indicating that the graphene surface acts as a catalyst of methane decomposition. On the other hand, the barriers are still much higher than on the nickel surface. Methane dissociation therefore occurs at a higher rate on nickel than on graphene. This reaction is a prerequisite for graphene growth from a precursor gas. Thus, the growth of the first monolayer should be a fast and efficient process while subsequent layers grow at a diminished rate and in a more controllable manner. Defects may also influence reaction energetics. This is evident from our results, in which simple defects (Stone-Wales defect and nitrogen substitution) lead to different free energy landscapes at both dissociation and adsorption steps of the process.

  4. The investigation of adsorption and dissociation of H2O on Li2O (111) by ab initio theory

    Science.gov (United States)

    Kong, Xianggang; Yu, You; Ma, Shenggui; Gao, Tao; Lu, Tiecheng; Xiao, Chengjian; Chen, Xiaojun; Zhang, Chuanyu

    2017-06-01

    The adsorption and dissociation mechanism of H2O molecule on the Li2O (111) surface have been systematically studied by using the density functional theory calculations. The parallel and vertical configurations of H2O at six different symmetry adsorption sites on the Li2O (111) surface are considered. In our calculations, it is suggested that H2O can dissociate on the perfect Li2O surface, of which the corresponding adsorption energy is 1.118 eV. And the adsorption energy decrease to be 0.241 eV when oxygen atom of H2O bonds to lithium atom of the slab. The final configurations are sensitive to the initial molecular orientation. By Bader charge analysis, the charge transfer from slab to adsorbed H2O/OH can be found due to the downward shift of lowest-unoccupied molecular orbital. We also analyze the vibrational frequencies at the Brillouin Zone centre for H2O molecule adsorbed on the stoichiometric surface. Due to the slightly different structure parameters, the calculated values of the vibrational frequencies of hydroxyl group range from 3824 to 3767 cm-1. Our results agree well with experimental results performed in FT-IR spectrum, which showed that an absorption peak of OH group appeared at 3677 cm-1 at room temperature.

  5. The influence of physical parameters on the adsorption of iodine 131 by activated charcoals

    International Nuclear Information System (INIS)

    Billard, F.; Chevalier, G.; Caron, J.; Van Der Meersch, J.

    1966-01-01

    Following an outline of the means of generating iodine 131 in the gas phase and a brief description of the apparatus used, the authors analyse the experimental results obtained on the trapping of iodine 131 by activated charcoal. The efficiency depends concurrently on the relative humidity and the iodine concentration of the air. While it is independent of this concentration in dry air, it does not exceed 50 in moist air, whatever the bed depth, when the concentration is less than 1 mCi/m 3 , then it increases with the concentrations to reach values close to those obtained in dry air for concentrations of around 1000 Ci/m 3 . At the same time the efficiency of a dust filter with respect to iodine remains very low in dry air whatever the iodine concentration; in moist air this efficiency, which is high at low concentrations, decreases when the latter increases. In addition if a charcoal bed is divided into several beds, separated by an amount corresponding to a passage time of about a second, it is found that the efficiency of the whole is appreciably higher than that of the initial bed. These results appear to establish the existence of at least two forms of iodine, one molecular form and one particulate form probably formed by clusters, the forms equilibrium being functions of the relative concentrations of iodine and water vapour in the air. The third form evidence, a gaseous form compound, remains hypothetical; the experimental curves can be explained either by the molecular and particular forms reversibility or by the increase of clusters size with the relative humidity of the air. (authors) [fr

  6. Improving COIL Efficiency By Iodine Pre-Dissociation Via Corona Discharge In The Transonic Section Of The Secondary Flow

    National Research Council Canada - National Science Library

    Rosenwaks, Zamik; Barmashenko, Boris

    2006-01-01

    .... Experimental measurements of the lasing power and small signal gain with and without the iodine predissociation caused by the corona discharge and determination of the power enhancement factor...

  7. The investigation of adsorption and dissociation of H2O on Li2O (111) by ab initio theory

    International Nuclear Information System (INIS)

    Kong, Xianggang; Yu, You; Ma, Shenggui; Gao, Tao; Lu, Tiecheng; Xiao, Chengjian; Chen, Xiaojun; Zhang, Chuanyu

    2017-01-01

    Highlights: • The adsorption structures of H 2 O on Li 2 O (111) are obtained by calculations. • By Bader charge analysis, the charge translation from slab to adsorbate is found. • The vibrational frequencies of adsorbate are in line with the experimental values. - Abstract: The adsorption and dissociation mechanism of H 2 O molecule on the Li 2 O (111) surface have been systematically studied by using the density functional theory calculations. The parallel and vertical configurations of H 2 O at six different symmetry adsorption sites on the Li 2 O (111) surface are considered. In our calculations, it is suggested that H 2 O can dissociate on the perfect Li 2 O surface, of which the corresponding adsorption energy is 1.118 eV. And the adsorption energy decrease to be 0.241 eV when oxygen atom of H 2 O bonds to lithium atom of the slab. The final configurations are sensitive to the initial molecular orientation. By Bader charge analysis, the charge transfer from slab to adsorbed H 2 O/OH can be found due to the downward shift of lowest-unoccupied molecular orbital. We also analyze the vibrational frequencies at the Brillouin Zone centre for H 2 O molecule adsorbed on the stoichiometric surface. Due to the slightly different structure parameters, the calculated values of the vibrational frequencies of hydroxyl group range from 3824 to 3767 cm −1 . Our results agree well with experimental results performed in FT-IR spectrum, which showed that an absorption peak of OH group appeared at 3677 cm −1 at room temperature.

  8. Impact of Polymer-bound Iodine on Fibronectin Adsorption and Osteoblast Cell Morphology Radiopaque Medical Polymers: Tyrosine-derived Polycarbonate Blends as a Model System

    Science.gov (United States)

    Aamer, Khaled A.; Genson, Kirsten L.; Kohn, Joachim; Becker, Matthew L.

    2012-01-01

    Imaging of polymer implants during surgical implantations is challenging in that most materials lack sufficient X-ray contrast. Synthetic derivatization with iodine serves to increase the scattering contrast but results in distinct physico-chemical properties in the material which influence subsequent protein adsorption and cell morphology behavior. Herein we report the impact of increasing iodine inclusion on the cell morphology (cell area and shape) of MC3T3-E1 osteoblasts on a series of homopolymers and discrete blend thin films of poly(desaminotyrosyl tyrosine ethyl ester carbonate), poly(DTE carbonate) and an iodinated analogue poly(I2-DTE carbonate). Cell morphology is correlated to film chemical composition via measuring Fibronectin (FN) adhesion protein adsorption profile on these films. FN exhibits up to 2 fold greater adsorption affinity for poly(I2-DTE carbonate) than (poly(DTE carbonate)). A correlation was established between cell area, roundness and the measured FN adsorption profile on the blend films up to 75 % by mass poly(I2-DTE carbonate). Data suggest that incorporation of iodine within the polymer backbone has a distinct impact on the way FN proteins adsorb to the surface and within the studied blend systems; the effect is composition dependent. PMID:19645443

  9. 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.

  10. Adsorption and possible dissociation of glucose by the [BN fullerene-B6]- magnetic nanocomposite. In silico studies

    Science.gov (United States)

    Anota, E. Chigo; Villanueva, M. Salazar; Shakerzadeh, E.; Castro, M.

    2018-02-01

    The adsorption, activation and possible dissociation of the glucose molecule on the magnetic [BN fullerene-B6]- system is performed by means of density functional theory calculations. Three models of magnetic nanocomposites were inspected: i) pristine BN fullerene, BN fullerene functionalized with a magnetic B6 cluster which generates two structures: ii) pyramidal (P) and iii) triangular (T). Chemical interactions of glucose appear for all these cases; however, for the BNF:B6(T)—glucose system, the interaction generates an effect of dissociation on glucose, due to the magnetic effects, since it has high spin multiplicity. The latter nanocomposite shows electronic behavior like-conductor and like-semi-conductor for the P and T geometries, respectively. Intrinsic magnetism associated to values of 1.0 magneton bohr (µB) for the pyramidal and 5.0 µB for the triangular structure, high polarity, and low-chemical reactivity are found for these systems. These interesting properties make these functionalized fullerenes a good option for being used as nano-vehicles for drug delivery. These quantum descriptors remain invariant when the [BN]-fullerene and [BNF:B6 (P) or (T)]- nanocomposites are interacting with the glucose molecule. According to the determined adsorption energy, chemisorption regimes occur in both the phases: gas and aqueous medium.

  11. Effect of Spin Multiplicity in O2 Adsorption and Dissociation on Small Bimetallic AuAg Clusters.

    Science.gov (United States)

    García-Cruz, Raúl; Poulain, Enrique; Hernández-Pérez, Isaías; Reyes-Nava, Juan A; González-Torres, Julio C; Rubio-Ponce, A; Olvera-Neria, Oscar

    2017-08-17

    To dispose of atomic oxygen, it is necessary the O 2 activation; however, an energy barrier must be overcome to break the O-O bond. This work presents theoretical calculations of the O 2 adsorption and dissociation on small pure Au n and Ag m and bimetallic Au n Ag m (n + m ≤ 6) clusters using the density functional theory (DFT) and the zeroth-order regular approximation (ZORA) to explicitly include scalar relativistic effects. The most stable Au n Ag m clusters contain a higher concentration of Au with Ag atoms located in the center of the cluster. The O 2 adsorption energy on pure and bimetallic clusters and the ensuing geometries depend on the spin multiplicity of the system. For a doublet multiplicity, O 2 is adsorbed in a bridge configuration, whereas for a triplet only one O-metal bond is formed. The charge transfer from metal toward O 2 occupies the σ* O-O antibonding natural bond orbital, which weakens the oxygen bond. The Au 3 ( 2 A) cluster presents the lowest activation energy to dissociate O 2 , whereas the opposite applies to the AuAg ( 3 A) system. In the O 2 activation, bimetallic clusters are not as active as pure Au n clusters due to the charge donated by Ag atoms being shared between O 2 and Au atoms.

  12. ReaxFF Grand Canonical Monte Carlo simulation of adsorption and dissociation of oxygen on platinum (111)

    Science.gov (United States)

    Valentini, Paolo; Schwartzentruber, Thomas E.; Cozmuta, Ioana

    2011-12-01

    Atomic-level Grand Canonical Monte Carlo (GCMC) simulations equipped with a reactive force field (ReaxFF) are used to study atomic oxygen adsorption on a Pt(111) surface. The off-lattice GCMC calculations presented here rely solely on the interatomic potential and do not necessitate the pre-computation of surface adlayer structures and their interpolation. As such, they provide a predictive description of adsorbate phases. In this study, validation is obtained with experimental evidence (steric heats of adsorption and isotherms) as well as DFT-based state diagrams available in the literature. The ReaxFF computed steric heats of adsorption agree well with experimental data, and this study clearly shows that indirect dissociative adsorption of O2 on Pt(111) is an activated process at non-zero coverages, with an activation energy that monotonically increases with coverage. At a coverage of 0.25 ML, a highly ordered p(2 × 2) adlayer is found, in agreement with several low-energy electron diffraction observations. Isotherms obtained from the GCMC simulations compare qualitatively and quantitatively well with previous DFT-based state diagrams, but are in disagreement with the experimental data sets available. ReaxFF GCMC simulations at very high coverages show that O atoms prefer to bind in fcc hollow sites, at least up to 0.8 ML considered in the present work. At moderate coverages, little to no disorder appears in the Pt lattice. At high coverages, some Pt atoms markedly protrude out of the surface plane. This observation is in qualitative agreement with recent STM images of an oxygen covered Pt surface. The use of the GCMC technique based on a transferable potential is particularly valuable to produce more realistic systems (adsorbent and adsorbate) to be used in subsequent dynamical simulations (Molecular Dynamics) to address recombination reactions (via either Eley-Rideal or Langmuir-Hinshelwood mechanisms) on variously covered surfaces. By using GCMC and Molecular

  13. Oxygen adsorption and dissociation during the oxidation of monolayer Ti2C

    KAUST Repository

    Gan, Liyong

    2013-08-20

    Exfoliated two-dimensional early transition metal carbides and carbonitrides are usually not terminated by metal atoms but saturated by O, OH, and/or F, thus making it difficult to understand the surface structure evolution and the induced electronic modifications. To fill this gap, density functional theory and molecular dynamics simulations are performed to capture the initial stage of the oxidation process of Ti2C, a prototypical example from the recently fabricated class of two-dimensional carbides and carbonitrides. It is shown that the unsaturated Ti 3d orbitals of the pristine Ti2C surface interact strongly with the approaching O2 molecules, resulting in barrierless O2 dissociation. The diffusion of the dissociated O atoms is also found to be very facile. Molecular dynamics simulations suggest that both dissociation and diffusion are enhanced as the O2 coverage increases to 0.25 monolayer. For a coverage of less than 0.11 monolayer, the adsorbates lead to a minor modification of the electronic properties of Ti2C, while the modification is remarkable at 0.25 monolayer. The formed Ti2CO2 after O saturation is an indirect narrow gap semiconductor (0.33 eV) with high intrinsic carrier concentration at room temperature and high thermodynamic stability at intermediate temperature (e.g., 550 °C).

  14. Theoretical Investigation of Hydrogen Adsorption and Dissociation on Iron and Iron Carbide Surfaces Using the ReaxFF Reactive Force Field Method

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Chenyu; van Duin, Adri C.T.; Sorescu, Dan C.

    2012-06-01

    We have developed a ReaxFF reactive force field to describe hydrogen adsorption and dissociation on iron and iron carbide surfaces relevant for simulation of Fischer–Tropsch (FT) synthesis on iron catalysts. This force field enables large system (>>1000 atoms) simulations of hydrogen related reactions with iron. The ReaxFF force field parameters are trained against a substantial amount of structural and energetic data including the equations of state and heats of formation of iron and iron carbide related materials, as well as hydrogen interaction with iron surfaces and different phases of bulk iron. We have validated the accuracy and applicability of ReaxFF force field by carrying out molecular dynamics simulations of hydrogen adsorption, dissociation and recombination on iron and iron carbide surfaces. The barriers and reaction energies for molecular dissociation on these two types of surfaces have been compared and the effect of subsurface carbon on hydrogen interaction with iron surface is evaluated. We found that existence of carbon atoms at subsurface iron sites tends to increase the hydrogen dissociation energy barrier on the surface, and also makes the corresponding hydrogen dissociative state relatively more stable compared to that on bare iron. These properties of iron carbide will affect the dissociation rate of H{sub 2} and will retain more surface hydride species, thus influencing the dynamics of the FT synthesis process.

  15. Computational study of adsorption, diffusion, and dissociation of precursor species on the GaN (0 0 0 1) surface during GaN MOCVD

    Science.gov (United States)

    Won, Yong Sun; Lee, Jinuk; Kim, Changsung Sean; Park, Sung-Soo

    2009-02-01

    The adsorption, diffusion, and dissociation of precursor species, MMGa (monomethylgallium) and NH 3, on the GaN (0 0 0 1) surface have been investigated using the DFT (density functional theory) calculation combined with a GaN (0 0 0 1) surface cluster model. The energetics of NH 3(ad) dissociation on the surface proposed of NH 3(ad) via NH 2(ad) to NH(ad) was facile with small activation barriers. A combined analysis with surface diffusion of adatoms demonstrated Ga(ad) and NH(ad) become primary reactant species for 2D film growth, and N(ad) develops into a nucleation center. Our studies suggest the control of NH 3(ad) dissociation are essential to improve epitaxial film quality as well as Ga-rich condition. In addition, the adsorbability of H(ad)s resulted from NH 3(ad) dissociation were found to influence on the surface chemistry during film growth.

  16. Direct Visualization of 2-Butanol Adsorption and Dissociation on TiO2(110)

    International Nuclear Information System (INIS)

    Zhang, Zhenrong; Bondarchuk, Olexsandr; Kay, Bruce D.; White, J. M.; Dohnalek, Zdenek

    2007-01-01

    Atomically resolved scanning tunneling microscopy (STM) images of identical regions of a TiO2(110) surface were gathered before and after controlled doses of 2-butanol (CH3CH2CH(OH)CH3) at ambient temperature (∼300 K). When dosing is initiated, 2-butanol preferentially adsorbs at bridge-bonded oxygen vacancy (BBOv) sites and dissociates via O-H, not C-O, bond scission to form paired 2-butoxy and hydroxyl species evidenced by two local maxima in STM line profiles. The measured separation is 0.4 nm, slightly larger than the measured separation (0.3 nm) between neighboring bridge-bonded oxygen anions in the surface unit cell of TiO2(110). As the dose increases, but before all the BBOv are occupied, there is direct STM evidence of hydroxyl proton hopping to an adjacent oxygen anion row. This process is facilitated by species bound to 5-coordinate Ti4+ rows, presumably undissociated 2-butanol, that hop slowly compared the STM imaging time scale. The backbones of these mobile species are centered over the Ti4+ rows with preference for lying parallel to these rows. On the other hand, the carbon backbones of the 2-butoxy species that fill BBOv's are centered over the O2- rows and prefer an orientation perpendicular to these rows. As the oxygen vacancy concentration increases from 0.4 to 11% and 2-butanol is dosed the ratio of mobile species to 2-butoxy species decreases for doses that do not fill all the BBOv

  17. Elementary Steps of Syngas Reactions on Mo2C(001): Adsorption Thermochemistry and Bond Dissociation

    Energy Technology Data Exchange (ETDEWEB)

    Medford, Andrew

    2012-02-16

    Density functional theory (DFT) and ab initio thermodynamics are applied in order to investigate the most stable surface and subsurface terminations of Mo{sub 2}C(001) as a function of chemical potential and in the presence of syngas. The Mo-terminated (001) surface is then used as a model surface to evaluate the thermochemistry and energetic barriers for key elementary steps in syngas reactions. Adsorption energy scaling relations and Broensted-Evans-Polanyi relationships are established and used to place Mo{sub 2}C into the context of transition metal surfaces. The results indicate that the surface termination is a complex function of reaction conditions and kinetics. It is predicted that the surface will be covered by either C{sub 2}H{sub 2} or O depending on conditions. Comparisons to transition metals indicate that the Mo-terminated Mo{sub 2}C(001) surface exhibits carbon reactivity similar to transition metals such as Ru and Ir, but is significantly more reactive towards oxygen.

  18. The investigation of adsorption and dissociation of H{sub 2}O on Li{sub 2}O (111) by ab initio theory

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Xianggang [Institute of Atom and Molecular physics, Sichuan University, Chengdu, 610065 (China); Yu, You [College of Optoelectronic Technology, Chengdu University of Information Technology, Chengdu, 610225 (China); Ma, Shenggui [Institute of Atom and Molecular physics, Sichuan University, Chengdu, 610065 (China); Gao, Tao, E-mail: gaotao@scu.edu.cn [Institute of Atom and Molecular physics, Sichuan University, Chengdu, 610065 (China); Lu, Tiecheng [Department of Physics and Key Laboratory for Radiation Physics & Technology of Ministry of Education, Sichuan University, Chengdu, 610065 (China); Xiao, Chengjian; Chen, Xiaojun [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621900 (China); Zhang, Chuanyu [College of Geophysics, Chengdu University of Technology, Chengdu, 610059 (China)

    2017-06-15

    Highlights: • The adsorption structures of H{sub 2}O on Li{sub 2}O (111) are obtained by calculations. • By Bader charge analysis, the charge translation from slab to adsorbate is found. • The vibrational frequencies of adsorbate are in line with the experimental values. - Abstract: The adsorption and dissociation mechanism of H{sub 2}O molecule on the Li{sub 2}O (111) surface have been systematically studied by using the density functional theory calculations. The parallel and vertical configurations of H{sub 2}O at six different symmetry adsorption sites on the Li{sub 2}O (111) surface are considered. In our calculations, it is suggested that H{sub 2}O can dissociate on the perfect Li{sub 2}O surface, of which the corresponding adsorption energy is 1.118 eV. And the adsorption energy decrease to be 0.241 eV when oxygen atom of H{sub 2}O bonds to lithium atom of the slab. The final configurations are sensitive to the initial molecular orientation. By Bader charge analysis, the charge transfer from slab to adsorbed H{sub 2}O/OH can be found due to the downward shift of lowest-unoccupied molecular orbital. We also analyze the vibrational frequencies at the Brillouin Zone centre for H{sub 2}O molecule adsorbed on the stoichiometric surface. Due to the slightly different structure parameters, the calculated values of the vibrational frequencies of hydroxyl group range from 3824 to 3767 cm{sup −1}. Our results agree well with experimental results performed in FT-IR spectrum, which showed that an absorption peak of OH group appeared at 3677 cm{sup −1} at room temperature.

  19. Dissociative adsorption of environment-friendly insulating medium C3F7CN on Cu(111) and Al(111) surface: A theoretical evaluation

    Science.gov (United States)

    Zhang, Xiaoxing; Li, Yi; Chen, Dachang; Xiao, Song; Tian, Shuangshuang; Tang, Ju; Wang, Dibo

    2018-03-01

    SF6 is extensively used in electrical applications because of its excellent insulation and arc extinguishing performance, but its strong greenhouse effect has negative impact on the atmosphere. The excellent performance of C3F7CN in greenhouse effect, insulation ability, safety, and thermal stability has been demonstrated, indicating that this compound can replace SF6 in electrical applications. However, little information is available on the compatibility of C3F7CN with metals, such as copper and aluminum, in devices. Material compatibility between new gas mixtures and materials used in Gas Insulated Switchgear (GIS) should be investigated to determine the long-term behavior of materials. In this paper, dissociative adsorption of C3F7CN on Cu (1 1 1) and Al (1 1 1) surfaces were analyzed based on density functional theory. Adsorption energy, charge transfer, density of states, and electron density difference of interaction between C3F7CN and two metals were analyzed. It was found that the adsorption energy of C3F7CN adsorbed on Cu (1 1 1) and Al (1 1 1) is both below 0.8 eV. This value indicates that the interaction between them is not very strong. In addition, the dissociation reaction path of gas molecules after adsorption requires certain activation energy. Therefore, C3F7CN and copper or aluminum have certain compatibility and the compatibility of C3F7CN with aluminum is better than that of copper. Related results provide a reference for predicting the aging mechanism of equipment and the selection or modification of major materials for equipment.

  20. Synthesis of methanol from CO2hydrogenation promoted by dissociative adsorption of hydrogen on a Ga3Ni5(221) surface.

    Science.gov (United States)

    Tang, Qingli; Shen, Zhemin; Huang, Liang; He, Ting; Adidharma, Hertanto; Russell, Armistead G; Fan, Maohong

    2017-07-19

    Catalytic carbon dioxide (CO 2 ) hydrogenation to liquid fuels including methanol (CH 3 OH) has attracted great attention in recent years. In this work, density functional theory (DFT) calculations have been employed to study the reaction mechanisms of CO 2 hydrogenation to CH 3 OH on Ga 3 Ni 5 (221) surfaces. The results show that all intermediates except for the O atom prefer to adsorb on Ni sites, and dissociative adsorption of hydrogen (H 2 ) on the Ga 3 Ni 5 (221) surface is almost barrierless and highly exothermic, favoring CO 2 hydrogenation. Moreover, the presence of Ga indeed enhances the dissociative adsorption of H 2 , and this is verified by the projected density of states (PDOS) analysis. Importantly, three possible reaction pathways based on formate (HCOO) and hydrocarboxyl (COOH) formations and reverse water gas shift (rWGS) with carbon monoxide (CO) hydrogenation have been discussed. It is found that CO 2 reduction to CH 3 OH in these pathways prefers to occur entirely via the Langmuir-Hinshelwood (L-H) mechanism. COOH generation is the most favorable pathway because the HCOO and rWGS with CO hydrogenation pathways have high energy barriers and the resulting HCOOH intermediate in the HCOO pathway is unstable. In the COOH reaction pathway, CO 2 is firstly hydrogenated to trans-COOH, followed by the formation of COH via three isomers of COHOH, its hydrogenation to trans-HCOH, and then the production of CH 3 OH via a CH 2 OH intermediate.

  1. Theoretical insights into the effect of terrace width and step edge coverage on CO adsorption and dissociation over stepped Ni surfaces.

    Science.gov (United States)

    Yang, Kuiwei; Zhang, Minhua; Yu, Yingzhe

    2017-07-21

    Vicinal surfaces of Ni are model catalysts of general interest and great importance in computational catalysis. Here we report a comprehensive study conducted with density functional theory on Ni[n(111) × (100)] (n = 2, 3 and 4) surfaces to explore the effect of terrace width and step edge coverage on CO adsorption and dissociation, a probe reaction relevant to many industrial processes. The coordination numbers (CN), the generalized coordination numbers and the d band partial density of states (d-PDOS) of Ni are identified as descriptors to faithfully reflect the difference of the step edge region for Ni[n(111) × (100)]. Based on analysis of the energy diagrams for CO activation and dissociation as well as the structural features of the Ni(311), Ni(211) and Ni(533) surfaces, Ni(211) (n = 3) is proposed as a model of adequate representativeness for Ni[n(111) × (100)] (n≥ 3) surface groups in investigating small molecule activation over such stepped structures. Further, a series of Ni(211) surfaces with the step edge coverage ranging from 1/4 to 1 monolayer (ML) were utilized to assess their effect on CO activation. The results show that CO adsorption is not sensitive to the step edge coverage, which could readily approach 1 ML under a CO-rich atmosphere. In contrast, CO dissociation manifests strong coverage dependence when the coverage exceeds 1/2 ML, indicating that significant adsorbate-adsorbate interactions emerge. These results are conducive to theoretical studies of metal-catalyzed surface processes where the defects play a vital role.

  2. D2 dissociative adsorption on and associative desorption from Si(100): Dynamic consequences of an ab initio potential energy surface

    DEFF Research Database (Denmark)

    Luntz, A. C.; Kratzer, Peter

    1996-01-01

    favors the symmetric one. Under the conditions of many experiments, either could dominate. The calculations show quite weak dynamic coupling to the Si lattice for both paths, i.e., weak surface temperature dependences to dissociation and small energy loss to the lattice upon desorption......Dynamical calculations are reported for D-2 dissociative chemisorption on and associative desorption from a Si(100) surface. These calculations use the dynamically relevant effective potential which is based on an ab initio potential energy surface for the ''pre-paired'' species. Three coordinates...

  3. Electric Discharge and Afterglow Kinetics for Laser Mixtures with Carbon Monoxide, Oxygen and Iodine

    National Research Council Canada - National Science Library

    Ionin, Andrey

    2006-01-01

    ... lasers, for producing electrically excited oxygen and for obtaining iodine atoms via iodine dissociation, which can be extremely useful for the development of the electrically assisted oxygen-iodine laser...

  4. Adsorption

    Directory of Open Access Journals (Sweden)

    Sushmita Banerjee

    2017-05-01

    Full Text Available Application of saw dust for the removal of an anionic dye, tartrazine, from aqueous solutions has been investigated. The experiments were carried out in batch mode. Effect of the parameters such as pH, initial dye concentration and temperature on the removal of the dye was studied. Equilibrium was achieved in 70 min. Maximum adsorption of dye was achieved at pH 3. Removal percent was found to be dependent on the initial concentration of dye solution, and maximum removal was found to be 97% at 1 mg/L of tartrazine. The removal increases from 71% to 97% when the initial concentration of dye solution decreases from 15 mg/L to 1 mg/L. The equilibrium adsorption data were analyzed by Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. The (Langmuir adsorption capacity of the adsorbent is found to be 4.71 mg/g at 318 K. Kinetic modeling of the process of removal was carried out and the process of removal was found to follow a pseudo second order model and the value of rate constant for adsorption process was calculated as 2.7 × 10−3 g mg−1 min−1 at 318 K. The thermodynamic parameters such as change in free energy (ΔG°, enthalpy (ΔH° and entropy (ΔS° were determined and the negative values of ΔG° indicated that the process of removal was spontaneous at all values of temperatures. Further, the values of ΔH° indicated the endothermic nature of the process of removal.

  5. Surface species formed by the adsorption and dissociation of water molecules on Ru(0001) surface containing a small coverage of carbon atoms studied by scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Dept of Materials Science and Engineering UCB; Dept of Applied Science and Technology, UCB; Institut de Ciencia de Materials de Barcelona, Barcelona, Spain; Instituto de Ciencia de Materiales de Madrid, Madrid, Spain; Department of Mechanical Engineering, Yale University; Salmeron, Miquel; Shimizu, Tomoko K.; Mugarza, Aitor; Cerda, Jorge I.; Heyde, Markus; Qi, Yabing; Schwarz, Udo D.; Ogletree, D. Frank; Salmeron, Miquel

    2008-04-26

    The adsorption and dissociation of water on a Ru(0001) surface containing a small amount ({le} 3 %) of carbon impurities was studied by scanning tunneling microscopy (STM). Various surface species are formed depending on the temperature. These include molecular H{sub 2}O, H{sub 2}O-C complexes, H, O, OH and CH. Clusters of either pure H{sub 2}O or mixed H{sub 2}O-OH species are also formed. Each of these species produces a characteristic contrast in the STM images and can be identified by experiment and by ab initio total energy calculations coupled with STM image simulations. Manipulation of individual species via excitation of vibrational modes with the tunneling electrons has been used as supporting evidence.

  6. Technetium, Iodine, and Chromium Adsorption/Desorption Kd Values for Vadose Zone Pore Water, ILAW Glass, and Cast Stone Leachates Contacting an IDF Sand Sequence

    Energy Technology Data Exchange (ETDEWEB)

    Last, George V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Snyder, Michelle M.V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stephenson, John R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Leavy, Ian I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Strickland, Christopher E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bacon, Diana H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, Nikolla [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Serne, R. Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-11-01

    Performance and risk assessments of immobilized low-activity waste (ILAW) at the Integrated Disposal Facility (IDF) have shown that risks to groundwater are quite sensitive to adsorption-desorption interactions occurring in the near- and far-field environment. These interactions between the underlying sediments and the contaminants present in the leachates that descend from the buried glass, secondary waste grouts, and potentially Cast Stone low-activity waste packages have been represented in these assessments using the contaminant distribution coefficient (Kd) construct. Some contaminants (99Tc, 129I, and Cr) present in significant quantities in these wastes have low Kd values and tend to drive risk to public health and the environment. Relatively small changes in the Kd value can cause relatively large changes in the retardation factor. Thus, even relatively small uncertainty in the Kd value can result in a relatively large uncertainty in the risk determined through performance assessment modeling. The purpose of this study is to further reduce the uncertainty in Kd values for 99Tc, iodine (iodide and iodate), and Cr (chromate; CrO42-) by conducting systematic adsorption-desorption experiments using actual sand-dominated Hanford formation sediments from beneath the IDF and solutions that closely mimic Hanford vadose zone pore water and leachates from Cast Stone and ILAW glass waste forms. Twenty-four batch and 21 flow-through column experiments were conducted, yielding 261 Kd measurements for these key contaminants, and contributing to our understanding for predicting transport from wastes disposed to the IDF. While the batch Kd methodology is not well-suited for measuring Kd values for non-sorbing species (as noted by the U.S. Environmental Protection Agency), the batch Kd results presented here are not wholly inconsistent with the column Kd results, and could be used for sensitivity purposes. Results from the column experiments are consistent with the best

  7. O{sub 2} adsorption and dissociation on the Pd{sub 13-n}Ni{sub n}@Pt{sub 42} (n = 0, 1, 12, and 13) tri-metallic nanoparticles: A DFT study

    Energy Technology Data Exchange (ETDEWEB)

    Li, Sha; Yang, Yongpeng; Huang, Shiping, E-mail: huangsp@mail.buct.edu.cn

    2017-07-15

    Highlights: • O{sub 2} adsorption and dissociation on Pd{sub 13-n}Ni{sub n}@Pt{sub 42} NPs are performed by DFT. • Adsorption energies of O{sub 2} and O are strongly affected by the coordination number. • Adsorption energy and d-band center displays the opposite change tendency. • Ni{sub 13}@Pt{sub 42} is the most active catalyst among Pd{sub 13-n}Ni{sub n}@Pt{sub 42} (n = 0, 1, 12, and 13) NPs. - Abstract: Density functional theory calculations are performed to investigate O{sub 2} adsorption and dissociation on the icosahedral Pd{sub 13-n}Ni{sub n}@Pt{sub 42} (n = 0, 1, 12, and 13) tri-metallic nanoparticles. The parallel adsorption of O{sub 2} on Pd{sub 13-n}Ni{sub n}@Pt{sub 42} (n = 0, 1, 12, and 13) is stronger than the vertical adsorption. The adsorption of O{sub 2} on the bridge site (B1) is favorable in the Pd{sub 13-n}Ni{sub n}@Pt{sub 42} (n = 0, 1, 12, and 13) nanoparticles, while the adsorption of O atom on the hollow site (H1) is preferred. The adsorption energies of O{sub 2} and O are strongly affected by the coordination number. Low coordination site shows strong adsorption of O{sub 2} and O on the Pd{sub 13-n}Ni{sub n}@Pt{sub 42} (n = 0, 1, 12, and 13) nanoparticles. The adsorption energies of O{sub 2} and O atoms are found to be correlated well with the d-band center of surface Pt. For the Pd{sub 13-n}Ni{sub n}@Pt{sub 42} (n = 0, 1, 12, and13) nanoparticles catalysts, the ORR activity follows the order of Ni{sub 13}@Pt{sub 42} > Pd{sub 13}@Pt{sub 42} > Pd{sub 12}Ni{sub 1}@Pt{sub 42} > Pd{sub 1}Ni{sub 12}@Pt{sub 42}, illustrating that the Ni{sub 13}@Pt{sub 42} is the strongest ORR activity among the Pd{sub 13-n}Ni{sub n}@Pt{sub 42} (n = 0, 1, 12, and13) nanoparticles catalysts. Our results have important significance to understand the mechanism of O{sub 2} dissociation on the Pd{sub 13-n}Ni{sub n}@Pt{sub 42} (n = 0, 1, 12, and 13) tri-metallic nanoparticles.

  8. Radionuclide Basics: Iodine

    Science.gov (United States)

    ... Search Radiation Protection Contact Us Share Radionuclide Basics: Iodine Iodine (chemical symbol I) is a chemical element. ... in the environment Iodine sources Iodine and health Iodine in the Environment All 37 isotopes of iodine ...

  9. Iodine Deficiency

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2009-01-01

    Iodine deficiency has multiple adverse effects in humans, termed iodine deficiency disorders, due to inadequate thyroid hormone production. Globally, it is estimated that 2 billion individuals have an insufficient iodine intake, and South Asia and sub-Saharan Africa are particularly affected.

  10. Analysis of Heat Release from Gain Medium of Chemical Oxygen Iodine Laser

    Science.gov (United States)

    Takeuchi, Noriyuki; Sugimoto, Daichi; Tei, Kazuyoku; Nanri, Kenzo; Fujioka, Tomoo

    2005-02-01

    Heat release into the operating gas of a chemical oxygen iodine laser is analyzed on the basis of stagnation and cavity pressures. The energy of excited oxygen molecules is released as heat in this device through pooling reactions, iodine dissociation, and the interactions of these processes with water vapor. The proposed estimation method is applied to the analysis of subsonic and transonic iodine injection schemes to examine energy loss during iodine dissociation. The results also provide the number n of excited oxygen molecules consumed in each iodine dissociation. The values of n were estimated to be n≥ 10 and n≥ 6 in the subsonic and transonic injection schemes, respectively.

  11. Iodine poisoning

    Science.gov (United States)

    ... medical tests or the treatment of thyroid disease Tincture of iodine Iodine is also used during the ... Seek immediate medical help. DO NOT make a person throw up unless told to do so by Poison Control or a health care professional. Give the person milk, or ...

  12. Dissociative Disorders

    Science.gov (United States)

    ... actions and identity. People with dissociative disorders escape reality in ways that are involuntary and unhealthy and ... conditions. Complications People with dissociative disorders are at increased risk of complications and associated disorders, such as: ...

  13. Iodine Deficiency

    Science.gov (United States)

    ... thyroid problems, such as nodules, hyperthyroidism and autoimmune thyroid disease. Administration of large amounts of iodine through medications ( ... Anaplastic Thyroid Cancer Complementary and Alternative Medicine in Thyroid Disease FNA Biopsy of Thyroid Nodules Goiter Graves’ Disease ...

  14. Micro-Cu4I4-MOF: reversible iodine adsorption and catalytic properties for tandem reaction of Friedel-Crafts alkylation of indoles with acetals.

    Science.gov (United States)

    Zhu, Neng-Xiu; Zhao, Chao-Wei; Wang, Jian-Cheng; Li, Yan-An; Dong, Yu-Bin

    2016-10-20

    We report a convenient approach, the first of its kind, to construct a microscale non-metal@MOF composite catalytic host-guest system for an organic tandem reaction. The reported porous Cu 4 I 4 -MOF is able to reversibly adsorb molecular iodine at room temperature. The obtained I 2 @Cu 4 I 4 -MOF host-guest system can be a highly heterogeneous catalyst to promote the Friedel-Crafts alkylation of indoles with acetals in a one-pot two-step fashion under solvent-free conditions at room temperature.

  15. Iodine in diet

    Science.gov (United States)

    Diet - iodine ... Many months of iodine deficiency in a person's diet may cause goiter or hypothyroidism . Without enough iodine, ... and older children. Getting enough iodine in the diet may prevent a form of physical and intellectual ...

  16. Iodine Satellite

    Science.gov (United States)

    Dankanich, John; Kamhawi, Hani; Szabo, James

    2015-01-01

    This project is a collaborative effort to mature an iodine propulsion system while reducing risk and increasing fidelity of a technology demonstration mission concept. 1 The FY 2014 tasks include investments leveraged throughout NASA, from multiple mission directorates, as a partnership with NASA Glenn Research Center (GRC), a NASA Marshall Space Flight Center (MSFC) Technology Investment Project, and an Air Force partnership. Propulsion technology is often a critical enabling technology for space missions. NASA is investing in technologies to enable high value missions with very small and low-cost spacecraft, even CubeSats. However, these small spacecraft currently lack any appreciable propulsion capability. CubeSats are typically deployed and drift without any ability to transfer to higher value orbits, perform orbit maintenance, or deorbit. However, the iodine Hall system can allow the spacecraft to transfer into a higher value science orbit. The iodine satellite (iSAT) will be able to achieve a (Delta)V of >500 m/s with 1,300 s. The iSAT spacecraft, illustrated in figure 1, is currently a 12U CubeSat. The spacecraft chassis will be constructed from aluminum with a finish to prevent iodine-driven corrosion. The iSAT spacecraft includes full three-axis control using wheels, magnetic torque rods, inertial management unit, and a suite of sensors and optics. The spacecraft will leverage heat generated by spacecraft components and radiators for a passive thermal control system.

  17. Iodine Satellite

    Science.gov (United States)

    Kamhawi, Hani; Dankanich, John; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Iodine Satellite (iSat) spacecraft will be the first CubeSat to demonstrate high change in velocity from a primary propulsion system by using Hall thruster technology and iodine as a propellant. The mission will demonstrate CubeSat maneuverability, including plane change, altitude change and change in its closest approach to Earth to ensure atmospheric reentry in less than 90 days. The mission is planned for launch in fall 2017. Hall thruster technology is a type of electric propulsion. Electric propulsion uses electricity, typically from solar panels, to accelerate the propellant. Electric propulsion can accelerate propellant to 10 times higher velocities than traditional chemical propulsion systems, which significantly increases fuel efficiency. To enable the success of the propulsion subsystem, iSat will also demonstrate power management and thermal control capabilities well beyond the current state-of-the-art for spacecraft of its size. This technology is a viable primary propulsion system that can be used on small satellites ranging from about 22 pounds (10 kilograms) to more than 1,000 pounds (450 kilograms). iSat's fuel efficiency is ten times greater and its propulsion per volume is 100 times greater than current cold-gas systems and three times better than the same system operating on xenon. iSat's iodine propulsion system consists of a 200 watt (W) Hall thruster, a cathode, a tank to store solid iodine, a power processing unit (PPU) and the feed system to supply the iodine. This propulsion system is based on a 200 W Hall thruster developed by Busek Co. Inc., which was previously flown using xenon as the propellant. Several improvements have been made to the original system to include a compact PPU, targeting greater than 80 percent reduction in mass and volume of conventional PPU designs. The cathode technology is planned to enable heaterless cathode conditioning, significantly increasing total system efficiency. The feed system has been designed to

  18. Generalized adsorption isotherms for molecular and dissociative adsorption of a polar molecular species on two polar surface geometries: Perovskite (100) (Pm-3m) and fluorite (111) (Fm-3m)

    Science.gov (United States)

    Danielson, Thomas; Hin, Celine; Savara, Aditya

    2016-08-01

    Lattice based kinetic Monte Carlo simulations have been used to determine a functional form for the second order adsorption isotherms on two commonly investigated crystal surfaces: the (111) fluorite surface and the (100) perovskite surface which has the same geometric symmetry as the NaCl (100) surface. The functional form is generalized to be applicable to all values of the equilibrium constant by a shift along the pressure axis. Functions have been determined for estimating the pressure at which a desired coverage would be achieved and, conversely, for estimating the coverage at a certain pressure. The generalized form has been calculated by investigating the surface adsorbate coverage across a range of thermodynamic equilibrium constants that span the range 10-26 to 1013. The equations have been shown to be general for any value of the adsorption equilibrium constant.

  19. Dissociative Disorders

    Science.gov (United States)

    ... that's frightening or highly unpredictable. The stress of war or natural disasters also can bring on dissociative ... adults who experience other traumatic events, such as war, natural disasters, kidnapping, torture, or extended, traumatic, early- ...

  20. The behavior of gaseous iodine in sand

    International Nuclear Information System (INIS)

    Takahashi, Kanji

    1974-01-01

    Radioactive iodine gas was passed through 10 different sands collected at rivers and hills. The relation between the amount of the loaded gas and the amount of adsorbed gas was determined at room temperature, 50 -- 60 0 C, and 90 -- 100 0 C under humidity of 2 sand. This amount was about 1 -- 3 times as much as that of monomolecular membrane adsorption, 0.2 -- 0.3 μg/cm 2 . The decrease of adsorption amount that accompanies the increase of humidity is attributable to the decrease of effective surface area of sand due to the presence of water. The transport of iodine in sand was studied by passing gaseous iodine through a glass tubing packed with sand. The distribution in the flow direction of iodine indicated that the ease of desorption depends upon the situation of adsorption. Easily desorbed case was named Henry type adsorption. Hardly desorbed case was named absorption type. Discussion is made on experimental results. (Fukutomi, T.)

  1. Gravimetric determination of the iodine number of carbon black

    International Nuclear Information System (INIS)

    Murphy, L.J. Jr.

    1991-01-01

    This paper discusses a gravimetric method for the determination of the iodine adsorption number of carbon black. It comprises determining the concentration of an accurately weighed iodine blank solution by adding a standardized titrant to the iodine solution until a titration endpoint is reached and determining the concentration of the iodine solution by accurately weighing the amount of the standardized titrant necessary to reach the endpoint, accurately weighing an amount of carbon black and adding an appropriate amount of an accurately weighed portion of the iodine solution, equilibrating the carbon black-iodine solution mixture, adding the standardized titrant to an accurately weighed portion of the supernatant from the carbon black-iodine mixture until a titration endpoint is reached and determining the concentration of the supernatant by accurately weighing the amount of the standardized titrant necessary to reach the endpoint, wherein the titration endpoint of the supernatant is obtained using an indicating and a reference electrode, and calculating the iodine adsorption number of the carbon black based on the gravimetrically determined concentration of the titrant, the iodine solution, and the supernatant

  2. Iodine and Pregnancy

    OpenAIRE

    Christina Yarrington; Elizabeth N. Pearce

    2011-01-01

    Iodine is a necessary element for the production of thyroid hormone. We will review the impact of dietary iodine status on thyroid function in pregnancy. We will discuss iodine metabolism, homeostasis, and nutritional recommendations for pregnancy. We will also discuss the possible effects of environmental contaminants on iodine utilization in pregnant women.

  3. An Investigation into the Effects of Mn Promotion on the Activity and Selectivity of Co/SiO2 for Fischer - Tropsch Synthesis: Evidence for Enhanced CO Adsorption and Dissociation

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gregory R.; Werner, Sebastian; Bell, Alexis T. (LBNL); (UCB)

    2016-03-04

    Mn is an effective promoter for improving the activity and selectivity of Co-based Fischer-Tropsch synthesis (FTS) catalysts, but the mechanism by which this promoter functions is poorly understood. The work reported here was aimed at defining the manner in which Mn interacts with Co and determining how these interactions affect the activity and selectivity of Co. Detailed measurements are reported for the kinetics of FTS as a function of Mn/Co ratio, temperature, and reactant partial pressure. These data are described by a single, two-parameter rate expression. Mn promotion was found to increase both the apparent rate constant for CO consumption and the CO adsorption constant. Further evidence for enhanced CO adsorption and dissociation was obtained from measurements of temperature-programmed desorption of CO and CO disproportionation rates, respectively. Our quantitative analysis of elemental maps obtained by STEM-EDS revealed that the promoter accumulates preferentially on the surface of Co nanoparticles at low Mn loadings, resulting in a rapid onset of improvements in the product selectivity as the Mn loading increases. For catalysts prepared with loadings higher than Mn/Co = 0.1, the additional Mn accumulates in the form of nanometer-scale particles of MnO on the support. In situ IR spectra of adsorbed CO show that Mn promotion increases the abundance of adsorbed CO with weakened C-O bonds. Furthermore, it is proposed that the cleavage of the C-O bond is promoted through Lewis acid-base interactions between the Mn2+ cations located at the edges of MnO islands covering the Co nanoparticles and the O atom of CO adsorbates adjacent to the MnO islands. The observed decrease in selectivity to CH4 and the increased selectivity to C5+ products with increasing Mn/Co ratio are attributed to a decrease in the ratio of adsorbed H to CO on the surface of the supported Co nanoparticles.

  4. 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.

  5. Iodine Gas Trapping using Granular Porous Bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jae Hwan; Shin, Jin Myeong; Park, Jang Jin; Park, Geun Il [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Yim, Mansung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-05-15

    {sup 129}I is a radionuclide with a very long half-life of 1.57 Χ 10{sup 7} years and has negative health effects to the human body. Therefore, the emission of {sup 129}I into the air is closely regulated by the Environmental Protection Agency (EPA). Many methods for trapping gaseous {sup 129}I have been developed thus far, including wet scrubbing and adsorption using silver loaded zeolites. Although wet scrubbing can effectively remove iodine, it suffers from corrosion of the vessel due to high concentration of the scrubbing solution. Silver loaded zeolites also show effectiveness in capturing {sup 129}I gas, yet weak thermal stability of physisorbed iodine remains a challenge. We studied a novel and facile method to trap iodine gas using bismuth. Granular bismuth having many pores was synthesized using bismuth nitrate and polyvinyl alcohol as a bismuth precursor and pore forming agent, respectively. Reaction of iodine and our samples resulted in an iodine capturing capacity of more than 2 times that of the commercial grade silver exchanged zeolite (AgX). Granular porous bismuths synthesized using bismuth nitrate and PVA show a promising performance in capturing iodine gas. The use of bismuth in trapping {sup 129}I gas can reduce the process cost as bismuth is cheap. Further study is going on to improve the mechanical property of granular porous bismuths for their easy handling.

  6. Experimental study of silver zeolite for the removal of elemental iodine

    International Nuclear Information System (INIS)

    Zhang Dafang; Qu Delin; Shen Ziwei; Zhang Jianzhou; Li Qingai; Zhao Suyan; Hu Xien; Wang Siqi

    1985-01-01

    Experiments on the removal of elemental iodine in carbon dioxide stream with silver zeolite were made to provide data for controling discharge level of radioiodine in burning tail gas produced in the nuclear fuel reprocessing from high-temperature gas-cooled reactor. This paper describes the experimental procedure, decontamination factor of iodine and the determination method of the adsorptive capacity. Experimental results show that silver zeolite is a satisfactory absorbent for the removal of the elemental iodine

  7. 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.

  8. Iodine deficiency and iodine excess in Jiangsu Province, China

    NARCIS (Netherlands)

    Zhao, J.

    2001-01-01

    Keywords:
    iodine deficiency, iodine excess, endemic goiter, drinking water, iodine intake, thyroid function, thyroid size, iodized salt, iodized oil, IQ, physical development, hearing capacity, epidemiology, meta-analysis, IDD, randomized trial, intervention, USA, Bangladesh,

  9. Zero-valent iron pretreatment for detoxifying iodine in liquid crystal display (LCD) manufacturing wastewater.

    Science.gov (United States)

    Lee, J W; Cha, D K; Oh, Y K; Ko, K B; Song, J S

    2009-05-15

    This study investigated reductive transformation of iodine by zero-valent iron (ZVI), and the subsequent detoxification of iodine-laden wastewater. ZVI completely reduced aqueous iodine to non-toxic iodide. Respirometric bioassay illustrated that the presence of iodine increase the lag phase before the onset of oxygen consumption. The length of lag phase was proportional to increasing iodine dosage. The reduction products of iodine by ZVI did not exhibit any inhibitory effect on the biodegradation. The cumulative biological oxidation associated with iodine toxicity was closely fitted to Gompertz model. When iodine-laden wastewater was continuously fed to a bench-scale activated sludge unit, chemical oxygen demand (COD) removal efficiencies decreased from above 90% to below 80% along with a marked decrease in biomass concentration. On the other hand, the COD removal efficiency and biomass concentration remained constant in the integrated ZVI-activated sludge system. Respirometric bioassay with real iodine-laden LCD manufacturing wastewater demonstrated that ZVI was effective for detoxifying iodine and consequently enhancing biodegradability of wastewater. This result suggested that ZVI pretreatment may be a feasible option for the removal of iodine in LCD processing wastewater, instead of more costly processes such as adsorption and chemical oxidation, which are commonly in the iodine-laden LCD wastewater treatment facility.

  10. Zero-valent iron pretreatment for detoxifying iodine in liquid crystal display (LCD) manufacturing wastewater

    International Nuclear Information System (INIS)

    Lee, J.W.; Cha, D.K.; Oh, Y.K.; Ko, K.B.; Song, J.S.

    2009-01-01

    This study investigated reductive transformation of iodine by zero-valent iron (ZVI), and the subsequent detoxification of iodine-laden wastewater. ZVI completely reduced aqueous iodine to non-toxic iodide. Respirometric bioassay illustrated that the presence of iodine increase the lag phase before the onset of oxygen consumption. The length of lag phase was proportional to increasing iodine dosage. The reduction products of iodine by ZVI did not exhibit any inhibitory effect on the biodegradation. The cumulative biological oxidation associated with iodine toxicity was closely fitted to Gompertz model. When iodine-laden wastewater was continuously fed to a bench-scale activated sludge unit, chemical oxygen demand (COD) removal efficiencies decreased from above 90% to below 80% along with a marked decrease in biomass concentration. On the other hand, the COD removal efficiency and biomass concentration remained constant in the integrated ZVI-activated sludge system. Respirometric bioassay with real iodine-laden LCD manufacturing wastewater demonstrated that ZVI was effective for detoxifying iodine and consequently enhancing biodegradability of wastewater. This result suggested that ZVI pretreatment may be a feasible option for the removal of iodine in LCD processing wastewater, instead of more costly processes such as adsorption and chemical oxidation, which are commonly in the iodine-laden LCD wastewater treatment facility

  11. Adsorption Properties of the Cu(115) Surface

    DEFF Research Database (Denmark)

    Godowski, P. J.; Groso, A.; Hoffmann, S. V.

    2010-01-01

    in context of substrate geometry and compared with the ones of other copper planes. There are no indications of dissociative adsorption of CO, only residual carbon and oxygen were found after adsorbate desorption around 220 K. CO molecules show a strong tendency to "on top" adsorption in sites far from...

  12. Iodine deficiency disorders

    International Nuclear Information System (INIS)

    Ali, S.M.

    1993-01-01

    Iodine deficiency (IDD) is one of the common problem in the diet. Iodine deficiency as prevalence of goiter in population occurs in the mountainous areas. There is consensus that 800 million people are at risk of IDD from living in iodine deficient area and 190 million from goiter. Very high prevalence of IDD in different parts of the world are striking. It has generally observed that in iodine-deficient areas about 50% are affected with goiter, 1-5% from cretinsim and 20% from impaired mental and/or mortor function. (A.B.)

  13. Iodine-paint interactions during a core fusion accident; Les interactions iode-peinture au cours d'un accident de fusion du coeur

    Energy Technology Data Exchange (ETDEWEB)

    Simondi-Teisseire, B. [Institut de Radioprotection et de Surete Nucleaire, Service d' etude et de recherche experimentale sur la chimie, 13 - Cadarache (France); Cantrel, L. [Institut de Radioprotection et de Surete Nucleaire, Laboratoire d' Etudes du corium et du Transfert de Radioelements, 13 - Cadarache (France); Fillet, S. [Institut de Radioprotection et de Surete Nucleaire, Laboratoire d' Experimentation environnement et chimie, 13 - Cadarache (France)

    2011-01-15

    If a core fusion accident should occur, radioactive iodine would be released from the fuel and would reach the reactor containment building, and then react with wall paintings to form organic iodine compounds, i.e. volatile compounds which are difficult to filtrate and therefore would be released in the environment. This article briefly reports investigations of the formation/destruction mechanisms of these volatile iodine compounds, notably through the Epicur program. This program focused on two prevailing phenomena: the radiolytic oxidation of iodine present in sump water, and the production of volatile organic iodides from painted surfaces where iodine adsorption occurs. Iodine behaviour is modelled by using the Astec code

  14. Iodine-deficiency disorders

    NARCIS (Netherlands)

    Zimmermann, M.B.; Jooste, P.L.; Pandav, C.S.

    2008-01-01

    billion individuals worldwide have insufficient iodine intake, with those in south Asia and sub-Saharan Africa particularly affected. Iodine deficiency has many adverse effects on growth and development. These effects are due to inadequate production of thyroid hormone and are termed

  15. The iodine reactivity

    International Nuclear Information System (INIS)

    2003-01-01

    The iodine is an important element because it has long life isotopes (such as iodine 129) and a great mobility in natural media. Iodine presents a complex chemistry because of its volatility and its strong redox reactivity. The S.E.C.R. works to better understand the reactivity of this element in different natural, industrial or biological environments. It plays a part in thermochemical sites as a possible way of hydrogen formation. This seminar gives some aspects relative to the chemical reactivity of iodine, since its thermochemistry in the I/S cycles to produce hydrogen to its reactivity in the natural medium and its potential radiological impact. This document includes 4 presentations transparencies) dealing with: the 129 I cycle rejected in the low radioactive gaseous and liquid effluents of the La Hague reprocessing plant (C. Frechou); a bibliographic review of iodine retention in soils (F. Bazer-Bachi); the hydrogen production and the iodine/sulfur thermochemical cycle (role of iodine in the process); and the direct characterization by electro-spray ionization mass spectroscopy of iodine fixation by fulvic acids (P. Reiller, B. Amekraz, C. Moulin, V. Moulin)

  16. Marine geochemistry of iodine

    International Nuclear Information System (INIS)

    Kennedy, H.; Elderfield, H.

    1985-01-01

    Iodine has long been classified as a biophilic element with analyses showing that iodine is strongly enriched, relative to seawater concentrations in both plankton and particulate matter and that the concentration of iodine found in surface sediments is still further enriched relative to that found in the sedimenting particulate matter. The extent of enrichment of iodine relative to carbon in deep sea surface sediments has been shown to depend on the carbon accumulation rate. Iodine decomposition rates have been calculated and are shown to vary with the sedimentation rate in the same manner as has been shown for organic carbon. Vertical profiles of total dissolved iodine, iodate and iodide in interstitial waters of sediments from the north east Atlantic are characterised by three zones of reaction as identified by changes in the concentration of iodate and iodide. These reaction zones represent (i) iodide production (ii) iodide oxidation and (iii) iodate reduction. Pore water and solid phase iodine profiles from cores containing turbidite units have shown that iodine, released to pore waters as iodide during the oxidation of the organic matter, has been scavenged after diffusing upwards into a less reducing region of the sediment. (author)

  17. Iodine-induced thyroid dysfunction

    Science.gov (United States)

    Leung, Angela M.; Braverman, Lewis E.

    2017-01-01

    Purpose of review To summarize the mechanisms of iodine-induced hypothyroidism and hyperthyroidism, identify the risk factors for thyroid dysfunction following an iodine load, and summarize the major sources of excess iodine exposure. Recent findings Excess iodine is generally well tolerated, but individuals with underlying thyroid disease or other risk factors may be susceptible to iodine-induced thyroid dysfunction following acute or chronic exposure. Sources of increased iodine exposure include the global public health efforts of iodine supplementation, the escalating use of iodinated contrast radiologic studies, amiodarone administration in vulnerable patients, excess seaweed consumption, and various miscellaneous sources. Summary Iodine-induced thyroid dysfunction may be subclinical or overt. Recognition of the association between iodine excess and iodine-induced hypothyroidism or hyperthyroidism is important in the differential diagnosis of patients who present without a known cause of thyroid dysfunction. PMID:22820214

  18. Removal processes of iodine in reprocessing plants

    International Nuclear Information System (INIS)

    Goumondy, J.P.; Miquel, P.; Zellner, E.

    1981-09-01

    The principal parameters governing the behaviour of iodine in nuclear fuel processing plants are studied as are the conclusions to be reached for the design of future installations. This behaviour is essentially tied to the operating conditions of the dissolution and to the processing of the gases. It is preferable to desorb the maximum of iodine in the dissolution gases, low flow rate effluent in which it is known how to trap it efficiently and to limit to the minimum the residual quantity of iodine in the dissolution solution, a quantity which spreading throughout the plant as a whole and distributing in numerous effluents becomes very difficult to trap quantitatively. The existing trapping methods, either by chemical scrubbing processes, which are efficient for elemental iodine (alkaline scrubbing) or the organic iodides (Iodox and Mercurex processes), or by physical methods (adsorption on silver impregnated solid materials) should make it possible to obtain the requisite decontamination factors for the next plants, for normal operating conditions and in accidental situations [fr

  19. Iodine generator for reclaimed water purification

    Science.gov (United States)

    Wynveen, R. A.; Powell, J. D.; Schubert, F. H. (Inventor)

    1977-01-01

    The system disclosed is for controlling the iodine level in a water supply in a spacecraft. It includes an iodine accumulator which stores crystalline iodine, an electrochemical valve to control the input of iodine to the drinking water and an iodine dispenser. A pump dispenses fluid through the iodine dispenser and an iodine sensor to a potable water tank storage. The iodine sensor electronically detects the iodine level in the water, and through electronic means, produces a correction current control. The correction current control operates the electro-chemical iodine valve to release iodine from the iodine accumulator into the iodine dispenser.

  20. Semiquantitative test for iodine vapor above "complexed" iodine solutions.

    Science.gov (United States)

    Loran, M; Kleinmann, K

    1975-04-01

    A test to determine the extent to which free iodine exists in the vapor phase above the surface of "complexed iodine" solutions is described. The procedure is based on the qualitative starch-iodine test. The results can be related to the degree of complexation occurring between the polymer used in the preparation and iodine. Four products were tested: nonylphenoxypoly ethanol-iodine complex; polyvinyl pyrrolidine-iodine complex; popoxamer-iodine complex; and nonylphenoxypoly ethanol and polyvinyl pyrrolidone iodine complex. Free iodine in the vapor phase of the first product was detected in 90 minutes; the time for the other three was five days. For the tincture of iodine control, the time was 30 minutes.

  1. Separation technology for radioactive iodine from off-gas streams of nuclear facilities

    International Nuclear Information System (INIS)

    Fukasawa, Tetsuo; Funabashi, Kiyomi; Kondo, Yoshikazu.

    1994-01-01

    Iodine separation technology using an inorganic adsorption material has been investigated in order to apply the technology to the off-gas treatment systems of nuclear facilities. Iodine removal efficiencies were checked by laboratory experiments using simulated off-gas streams of various conditions and the developed adsorbent, silver impregnated alumina (AgA). Laboratory test results demonstrated effective iodine removal with high decontamination factors (DF's) at relatively high temperatures (≥100degC). Then the removal efficiency were confirmed using actual off-gas streams sampled from the dissolver off-gas treatment system of the Karlsruhe reprocessing plant. The DF's were over 10 3 with the AgA bed depth of 10 cm and showed little change during the adsorption period, which indicated applicability of the iodine removal technology with AgA to nuclear fuel reprocessing plants. Iodine absorption capacity and its release property were also investigated using simulated off-gas streams. The former had a value of ∼0.22 g/g-AgA and this value could well predict the breakthrough property. The adsorbed iodine was judged stable during the storage of AgA saturated with iodine in air at temperatures below 500degC and in water at ∼20degC after changing the adsorbed iodine form from AgIO 3 to AgI. Thus, the separation technology provided effective and stable iodine separation from the off-gas of nuclear facilities. (author)

  2. Is placental iodine content related to dietary iodine intake?

    LENUS (Irish Health Repository)

    Burns, R

    2011-08-01

    Delivery of iodine to the foetus depends not only on maternal dietary iodine intake but also on the presence of a functioning placental transport system. A role for the placenta as an iodine storage organ has been suggested, and this study compares the iodine content of placentas from women giving birth at term in Ireland and Iran, areas with median urinary iodine of 79 and 206 μg\\/l respectively.

  3. Highly Efficient Iodine Capture by Layered Double Hydroxides Intercalated with Polysulfides

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Shulan; Islam, Saiful M.; Shim, Yurina; Gu, Qingyang; Wang, Pengli; Li, Hao; Sun, Genban; Yang, Xiaojing; Kanatzidis, Mercouri G.

    2014-12-23

    We demonstrate strong iodine (I-2) vapor adsorption using Mg/Al layered double hydroxide (MgAl-LDH) nanocomposites intercalated with polysulfide (S-x(2-)) groups (S-x-LDH, x = 2, 4, 6). The as-prepared LDH/polysulfide hybrid materials display highly efficient iodine capture resulting from the reducing property of the intercalated polysulfides. During adsorption, the I-2 molecules are reduced to I-3(-) anions by the intercalated [S-x](2-) groups that simultaneously are oxidized to form S8. In addition to the chemical adsorption, additional molecular I-2 is physically captured by the LDH composites. As a result of these parallel processes, and despite their very low BET surface areas, the iodine capture capacities of S-2-LDH, S-4-LDH, and S-6-LDH are similar to 1.32, 1.52, and 1.43 g/g, respectively, with a maximum adsorption of 152% (wt %). Thermogravimetric and differential thermal analysis (TG-DTA), energy dispersive X-ray spectroscopy (EDS), and temperature-variable powder X-ray diffraction (XRD) measurements show the resulting I-3(-) ions that intercalated into the LDH gallery have high thermal stability (>= 350 degrees C). The excellent iodine adsorption performance combined with the facile preparation points to the S-x-LDH systems as potential superior materials for adsorption of radioactive iodine, a waste product of the nuclear power industry.

  4. Dissociation dynamics of methylal

    Energy Technology Data Exchange (ETDEWEB)

    Beaud, P.; Frey, H.-M.; Gerber, T.; Mischler, B.; Radi, P.P.; Tzannis, A.-P. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    The dissociation of methylal is investigated using mass spectrometry, combined with a pyrolytic radical source and femtosecond pump probe experiments. Based on preliminary results two reaction paths of methylal dissociation are proposed and discussed. (author) 4 fig., 3 refs.

  5. Iodine in meat in Macedonia

    International Nuclear Information System (INIS)

    Bogdanov, Bogdan; Gonev, Mihajlo; Tadzher, Isak

    2000-01-01

    Iodine deficiency in Macedonia still persists in a mild form. In 1999 the iodination of salt rose to 20 m gr iodine in Kg salt. The consumption of salt diminished after the last war from 20-30 gr salt per day to 10-20 gr salt daily. This shows that the problem of the elimination of iodine deficiency is being vigorously tackled. Since 1956 the iodine in salt in Macedonia rose to 10 m gr KI/Kg salt. The content of iodine in the Macedonian diet seems to be important. The amount of iodine in milk, eggs and bread is low as found by the investigation of MANU. The content of iodine in meat is low, compared to British meat is 10 times lower. The average iodine content in Macedonian meat is 95.15 micro gr per Kg, whereas in British meat it is 850-1510 micro gr iodine per k gr meat. (Original)

  6. Controversies in urinary iodine determinations

    OpenAIRE

    Soldin, Offie Porat

    2002-01-01

    Iodine deficiency (ID) is associated with increased prevalence of goiter, increased risk for neurodevelopmental disorders, and is the world’s leading cause of intellectual deficits. Iodine nutritional status of a population is assessed by measurements of urinary iodine concentrations which are also used to define, indicate, survey and monitor iodine deficiency and consequently its treatment. Several methods are available for urinary iodine determination. Discussed here are some of the limitat...

  7. 76 FR 82323 - Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units

    Science.gov (United States)

    2011-12-30

    ... Filtration and Adsorption Units AGENCY: Nuclear Regulatory Commission. ACTION: Draft regulatory guide... for Air Filtration and Adsorption Units of Postaccident Engineered-Safety-Feature Atmosphere Cleanup... testing of air filtration and iodine adsorption units of engineered-safety-feature (ESF) atmosphere...

  8. Production of radioactive iodine

    International Nuclear Information System (INIS)

    Schlyer, David J.

    2002-01-01

    This report discusses and compares various ways of Iodine-123 production using different targets such as 124 Xe, 122 Te, 123 Te, 124 Te and others. Requirements to targets and their design are discussed as well as nuclear reactions that lead to 123 I. Separation of the Iodine radioisotope is briefly presented along with comparison of the pathways in terms of the isotopic purity of target 123 I

  9. Iodine Hall Thruster

    Science.gov (United States)

    Szabo, James

    2015-01-01

    Iodine enables dramatic mass and cost savings for lunar and Mars cargo missions, including Earth escape and near-Earth space maneuvers. The demonstrated throttling ability of iodine is important for a singular thruster that might be called upon to propel a spacecraft from Earth to Mars or Venus. The ability to throttle efficiently is even more important for missions beyond Mars. In the Phase I project, Busek Company, Inc., tested an existing Hall thruster, the BHT-8000, on iodine propellant. The thruster was fed by a high-flow iodine feed system and supported by an existing Busek hollow cathode flowing xenon gas. The Phase I propellant feed system was evolved from a previously demonstrated laboratory feed system. Throttling of the thruster between 2 and 11 kW at 200 to 600 V was demonstrated. Testing showed that the efficiency of iodine fueled BHT-8000 is the same as with xenon, with iodine delivering a slightly higher thrust-to-power (T/P) ratio. In Phase II, a complete iodine-fueled system was developed, including the thruster, hollow cathode, and iodine propellant feed system. The nominal power of the Phase II system is 8 kW; however, it can be deeply throttled as well as clustered to much higher power levels. The technology also can be scaled to greater than 100 kW per thruster to support megawatt-class missions. The target thruster efficiency for the full-scale system is 65 percent at high specific impulse (Isp) (approximately 3,000 s) and 60 percent at high thrust (Isp approximately 2,000 s).

  10. Study of molecular iodine-epoxy paint mass transfer

    Energy Technology Data Exchange (ETDEWEB)

    Belval-Haltier, E. [Inst. de Protection et Surete Nucleaire, IPSN, CEN Cadarache, St. Paul-lez-Durance (France)

    1996-12-01

    The mass transfer phenomena may have a significant influence on the quantity of I{sub 2} which could be released following a severe accident of a nuclear power plant and specially the mass transfer of iodine onto containment surfaces. So, the objective of the present work was to evaluate which phase limited the adsorption process of iodine onto gaseous epoxy paint under a range of conditions which may be relevant to a severe reactor accident. In this aim, a series of experiments was conducted in which the sorption kinetics of molecular iodine, labelled with {sup 131}I, was measured by monitoring continuously the accumulation of this species on the epoxy surface. For each test condition, the initial deposition velocity was determined and the corresponding gas phase mass transfer, kg, was estimated by using the heat transfer analogy for a laminar flow passing over a flat plate. Then, the surface reaction rate, Kr, was deduced from these two values. Experiments performed indicated that iodine adsorption onto epoxy paint is highly dependent on temperature, relative humidity of the carrier gas and moisture content of the painted coupon. In dry air flow conditions, the adsorption of iodine onto paint was found to increase with temperature and to be limited by the surface reaction rate, Kr. The I{sub 2} adsorption rate was found to increase with the humidity of carrier gas and in some studied conditions, the initial deposition velocity appeared to be controlled by gas phase mass transfer rather than surface interaction. The same phenomenon has been observed with an increase of the initial water content of the painted coupon. (author) 6 figs., 1 tab., 8 refs.

  11. Determination of iodine 129 in vegetables using neutron activation analysis

    International Nuclear Information System (INIS)

    Quintana, Eduardo E.; Thyssen, Sandra M.; Bruno, Hector A.

    1999-01-01

    The developed methodology allows the determination of iodine 129 in vegetables, using neutron activation analysis. The chemical treatment removes the interferences present in these matrixes, as well as the bromine 82 originated in the activation process. The experimental method for the determination of iodine 129 by neutron activation analysis involves five steps: 1- digestion by alkaline fusion; 2- pre-irradiation purification of iodine 129 by distillation followed by solvent extraction, and adsorption on activated charcoal by distillation; 3- neutron irradiation; 4- post-irradiation purification of iodine 130 by distillation followed by solvent extraction; 5- gamma spectrometry. A chemical recovery of 95 % is obtained in the distillations, measured using iodine 131 as tracer. The whole process recovery is within 70 % and 85 %. The detection limit is 2 mBq/kg of sample, but several factors affect this value, such as type of vegetable, natural iodine concentration, irradiation time and neutron flux. The methodology developed is applied at environmental surveillance with safeguards proposes, in the detection of undeclared reprocessing of irradiated fuel. (authors)

  12. Controllable dissociations of PH3 molecules on Si(001).

    Science.gov (United States)

    Liu, Qin; Lei, Yanhua; Shao, Xiji; Ming, Fangfei; Xu, Hu; Wang, Kedong; Xiao, Xudong

    2016-04-01

    We demonstrate for the first time to our knowledge that controllable dissociation of PH3 adsorption products PHx (x = 2, 1) can be realized by STM (scanning tunneling microscope) manipulation techniques at room temperature. Five dissociative products and their geometric structures are identified via combining STM experiments and first-principle calculations and simulations. In total we realize nine kinds of controllable dissociations by applying a voltage pulse among the PH3-related structures on Si(001). The dissociation rates of the five most common reactions are measured by the I-t spectrum method as a function of voltage. The suddenly increased dissociation rate at 3.3 V indicates a transition from multivibrational excitation to single-step excitation induced by inelastic tunneling electrons. Our studies prove that selectively breaking the chemical bonds of a single molecule on semiconductor surface by STM manipulation technique is feasible.

  13. Iodination-deiodination

    International Nuclear Information System (INIS)

    Scherberg, N.; Refetoff, S.

    1977-01-01

    Bound iodine is released from radioiodinated nucleotides in polymers exposed to sodium bisulfite. The rate of bisulfite-catalyzed deiodination of pyrimidines can be controlled both by change of temperature or pH and is also dependent on the molecular association of the nucleotide. The rate of release of iodine from iodocytidine in polycytidylate is greater than the rate of elimination from RNA. Experiments testing the influence of base-pairing of the iodopyrimidines in synthetic polynucleotides showed that pairing of the substituted nucleotide protected the iodine bond. The rates of bisulfite-catalyzed deiodination of several radioiodinated RNAs were measured. The action of bisulfite on all single-stranded RNAs tested was multiphasic consisting of a rapid early deiodination reaction supplanted by a slower phase which was followed by reacceleration of release. The release of iodine from double-stranded RNA and DNA-RNA duplexes was retarded in comparison with the release from ribosomal and messenger RNA fractions. The deiodination profiles of single- and double-stranded RNA suggested that in the intermediate stage iodine release is governed by melting of paired zones of low stability. Late release may result from destabilization of the molecule through the addition of bisulfite to the pyrimidine ring or deamination. The effect of several substances expected to complex with polynucleotides was tested. The results show that a change in sensitivity to chemical deiodination may follow the interaction of small amounts of protein with polynucleotides

  14. Influence of iodine on the treatment of spacecraft humidity condensate to produce potable water

    Science.gov (United States)

    Symons, James M.; Muckle, Susan V.

    1990-01-01

    Several compounds in the ersatz humidity condensate do react with iodine to form iodine-substituted organic compounds (TOI), most notably phenol, acetaldehyde, ethanol, and sodium formate. Iodination of the ersatz humidity condensate produced 3.0 to 3.5 mg/L of TOI within 24 hours. The TOI that was produced by the passage of the ersatz humidity condensate through the first iodinated resin (IR) in the adsorption system was removed by the granular activated carbon that followed. TOI detected in the final effluent was formed by the reaction of the non-adsorbable condensate compounds with the final IR in the treatment series. The activated carbon bed series in the adsorption system performed poorly in its removal of TOC. The rapid breakthrough of TOC was not surprising, as the ersatz humidity condensate contained several highly soluble organic compounds, alcohols and organic acids.

  15. Efforts to Consolidate Chalcogels with Adsorbed Iodine

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Brian J.; Pierce, David A.; Chun, Jaehun

    2013-08-28

    This document discusses ongoing work with non-oxide aerogels, called chalcogels, that are under development at the Pacific Northwest National Laboratory as sorbents for gaseous iodine. Work was conducted in fiscal year 2012 to demonstrate the feasibility of converting Sn2S3 chalcogel without iodine into a glass. This current document summarizes the work conducted in fiscal year 2013 to assess the consolidation potential of non-oxide aerogels with adsorbed iodine. The Sn2S3 and Sb13.5Sn5S20 chalcogels were selected for study. The first step in the process for these experiments was to load them with iodine (I2). The I2 uptake was ~68 mass% for Sn2S3 and ~50 mass% for Sb13.5Sn5S20 chalcogels. X-ray diffraction (XRD) of both sets of sorbents showed that metal-iodide complexes were formed during adsorption, i.e., SnI4 for Sn2S3 and SbI3 for Sb13.5Sn5S20. Additionally, metal-sulfide-iodide complexes were formed, i.e., SnSI for Sn2S3 and SbSI for Sb13.5Sn5S20. No XRD evidence for unreacted iodine was found in any of these samples. Once the chalcogels had reached maximum adsorption, the consolidation potential was assessed. Here, the sorbents were heated for consolidation in vacuum-sealed quartz vessels. The Sb13.5Sn5S20 chalcogel was heated both (1) in a glassy carbon crucible within a fused quartz tube and (2) in a single-containment fused quartz tube. The Sn2S3 chalcogel was only heated in a single-containment fused quartz tube. In both cases with the single-containment fused quartz experiments, the material consolidated nicely. However, in both cases, there were small fractions of metal iodides not incorporated into the final product as well as fused quartz particles within the melt due to the sample attacking the quartz wall during the heat treatment. The Sb13.5Sn5S20 did not appear to attack the glassy carbon crucible so, for future experiments, it would be ideal to apply a coating, such as pyrolytic graphite, to the inner walls of the fused quartz vessel to prevent

  16. A theoretical investigation of water adsorption on titanium dioxide surfaces

    Science.gov (United States)

    Fahmi, Adil; Minot, Christian

    1994-03-01

    Water adsorption on various crystallographic faces of TiO 2 (anatase and rutile) are calculated using a periodic Hartree-Fock method. Titanium oxide is an amphoteric compound. Water adsorbs on the acidic site, the titanium atom, and then dissociates to give hydroxyl groups. The adsorption energy is larger on the (110) face of the rutile structure than on other faces and is correlated with its very acidic sites. The OH groups are oriented to maximize hydrogen bonding. Hydrogen bonding is particularly important for molecular adsorption on the (100) face of the rutile structure; in this case, the molecular adsorption becomes competitive with the dissociative one. The thermodynamics of water adsorption strongly favor dissociation when singly-coordinated oxygen atoms are present on the surface as it is in a perfectly truncated anatase surface.

  17. DFT research of methane preliminary dissociation on aluminum catalyst

    Science.gov (United States)

    Zhang, Minhua; Yu, Yingzhe; Zhang, Yongbo

    2013-09-01

    Using the quantum chemistry calculation module based on density functional theory (DFT), the stable adsorption states of Ni4 cluster on the surface of α-Al2O3(0 0 0 1) was investigated firstly, and then the most stable adsorption configuration was selected as the representative model of supported Ni4/α-Al2O3(0 0 0 1) catalyst to investigate the catalytic performance for methane preliminary dissociation. After theoretic calculation, it was found that the methane dissociation products prefer to be adsorbed on edge sites of Ni4 cluster, the adsorption priority sequence (from large to small) for the concerned species was H > O2 > CH3 ≫ CH4 > H2. Comparing with pure Ni4 cluster without support, the chemical adsorption ability of Ni4 cluster to H2 molecule is decreased after supporting on support, which would promote the desorption of product H2, and thus increase the H2 yield. The adsorption energy of O2 molecule on Ni4/α-Al2O3(0 0 0 1) is much higher than that of other molecules such as CH4 or H2 on Ni4 cluster surface. The Osbnd O bond length on the most stable adsorption site is elongated by 0.21 Å, which would promote the activation and dissociation of O2 molecule significantly and thus might facilitate the proceeding of further reaction.

  18. Volatilization of iodine from vegetation

    International Nuclear Information System (INIS)

    Amiro, B.D.; Johnston, F.L.

    1989-01-01

    Gaseous emissions of iodine were measured from bean plant foliage. A gamma-emitting iodine tracer, Na 125 I, was taken up by the plants from a hydroponic growth medium and released to a cuvette atmosphere. The dynamics of the flux were studied using a flow-through gamma detector. The relationship between leaf radioactive tracer activity and growth-medium activity was linear, as was the relationship between the iodine flux and both leaf and growth-medium activity. Iodine flux and leaf conductance to water responded similarly to changes in light levels, suggesting that the stomata may partially control the flux. The flux was inhibited by aeration of the hydroponic growth media, and we postulate that methylation causes the iodine flux. Iodine emissions from living vegetation probably contribute < 0.1% to the stable iodine concentration in the atmosphere above terrestrial areas. However, this pathway may be a direct route for radioactive iodine transport from contaminated soils to the atmosphere. (author)

  19. Highly efficient capture of iodine by Cu/MIL-101

    Science.gov (United States)

    Qi, Bingbing; Liu, Ying; Zheng, Tao; Gao, Qianhong; Yan, Xuewu; Jiao, Yan; Yang, Yi

    2018-02-01

    In order to improve the uptake capacity of MIL-101 for iodine, Cu nanoparticles doped MIL-101 were successfully synthesized through a facile method. The obtained Cu/MIL-101 was characterized by SEM, XRD, EDS, TEM, IR, TGA and BET to examine the chemical and thermal stabilities. The capture experiments for the adsorbents showed that the capture capacity of Cu/MIL-101 for volatile iodine is 342 wt%, which is higher than that of pure MIL-101. An I2 uptake of 342 wt% is the highest value reported among metal-organic frameworks. Furthermore, Cu/MIL-101 has a cycle ratio of 95% after three cycles and exhibits a better cyclicity than pure MIL-101. Meanwhile, Cu/MIL-101 shows an excellent reversible adsorption of iodine in solution.

  20. Mock iodine-125 radiation source

    International Nuclear Information System (INIS)

    Coffey, D.L.

    1976-01-01

    An intimate mixture of americium-241 and iodine-129 provides an energy spectrum that reliably simulates the spectrum of iodine-125 in a well-type detector. As such, it may be used as a long-lived standard to calibrate instruments such as well scintillation spectrometers in which measurements are to be made involving iodine-125

  1. The retention of iodine in stainless steel sample lines

    Energy Technology Data Exchange (ETDEWEB)

    Evans, G.J.; Deir, C. [Univ. of Toronto (Canada); Ball, J.M. [Whiteshell Laboratories, Pinawa (Canada)

    1995-02-01

    Following an accident in a multi-unit CANDU nuclear generating station, decontamination of air vented from containment would play a critical role in minimizing the release of iodine to the environment. The concentration of gas phase iodine in containment air would be measured using the post accident radiation monitoring system, requiring that air samples be passed through a considerable length of tubing to a remote location where the desired measurements could safely be made. A significant loss of iodine, due to adsorption on the sample line surfaces, could greatly distort the measurement. In this study, the retention of I{sub 2}(g) on stainless steel was evaluated in bench scale experiments in order to evaluate, and if possible minimise, the extent of any such line losses. Experiments at the University of Toronto were performed using 6 inch lengths of 1/4 inch stainless steel tubing. Air, containing I-131 labelled I{sub 2}(g), ranging in concentration from 10{sup {minus}10} to 10{sup {minus}6} mol/dm{sup 3} and relative humidity (:RH) from 20 to 90 %, was passed through tubing samples maintained at temperatures ranging from 25 to 90{degrees}C. Adsorption at low gas phase iodine concentrations differed substantially from that at higher concentrations. The rate of deposition was proportional to the gas phase concentration, giving support to the concept of a first order deposition velocity. The surface loading increased with increasing relative humidity, particularly at low RH values, while the deposition rate decreased with increasing temperature. Surface water on the steel may play an important role in the deposition process. The chemisorbed iodine was located primarily in areas of corrosion. Furthermore, water used to wash the steel contained Fe, Mn and iodine in the form of iodide, suggesting that I{sub 2} reacted to form metal iodides. The deposition of I{sub 2} was also found to depend on the initial surface condition.

  2. Deuteron diffractive dissociation

    International Nuclear Information System (INIS)

    Antunes, A.C.B.; Caruso, F.

    1984-01-01

    Deuteron diffractive dissociation is studied in the framework of the Three Components Deck Model. The applicability of this model to light nuclei diffractive dissociation is assumed. The existence of a slope-mass-cos theta correlation is pointed out. The relevant distributions are obtained. (Author) [pt

  3. Stability of Tritium and Iodine Sorbents in TPOG Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Jacob A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-04-01

    US regulations could require the removal of both iodine and tritium from the off-gas stream of a used nuclear fuel (UNF) reprocessing facility. Advanced tritium pretreatment is a pretreatment step that uses high concentrations of NOR2R in a gas stream to volatilize tritium and iodine from UNF prior to traditional dissolution. The gaseous effluent from this process would then require abatement to remove tritium and iodine, but high levels of NOR2R could have a detrimental effect on the ability of various solid sorbents to remove the volatile radionuclides. For tritium and iodine, the sorbents of interest are 3Å molecular sieve (3AMS) for tritium and reduced silver mordenite (AgP0 PZ), silver-functionalized silica-aerogel (AgAerogel), and silver-nitrate-impregnated alumina (AgA) for iodine. Prior research has demonstrated that exposure to high concentrations of NOR2R can reduce the iodine loading capacity of AgP0 PZ by > 90% when exposed for 1 week. Research in Japan has demonstrated that AgA is more robust to NOR2R exposure than AgZ. The testing described here was intended to assess the effects of high concentrations of NOR2R on the iodine capture capacity of AgA and the water adsorption capacity of 3AMS. To determine the effect of extended exposure of the sorbents to NOR2R, both 3AMS and AgA were aged in a 75% NOR2R environment prior to loading. The 3AMS samples were aged for 1, 4, and 5.5 weeks at 40°C. They were then loaded with water in a 10°C dew point stream (corresponding to a water concentration of ~12,000 ppmv) at 40°C. There was no significant change in the water adsorption capacity of the 3AMS upon exposure to 75% NOR2R. The AgA samples were aged for 1, 2, and 4 weeks at 150°C and were loaded with 50 ppmv IR2R at 150°C. The results show that the iodine capture capacity of AgA is reduced by exposure to high concentrations of NOR2R. The iodine capacity reductions were 16%, 36%, and 76% for 1, 2, and 4 week exposures, respectively

  4. Dissociated methanol test results

    Energy Technology Data Exchange (ETDEWEB)

    Finegold, J.G.; McKinnon, J.T.

    1982-04-01

    The design and testing of an automotive fuel system that provides hydrogen-rich gases to an internal combustion engine by catalytically cracking, or dissociating, methanol on board the vehicle is described. The vaporization and dissociation of methanol absorb heat from the engine exhaust and increase the lower heating value of the fuel by approximately 22%. In addition, raising the compression ratio and burning with excess air increase the engine thermal efficiency. Engine dynamometer test results with dissociated methanol demonstrated improvement in brake thermal efficiency compared to gasoline from 30% to 100% depending on engine speed and torque. Lower speeds and torques produce the largest improvements. Maps of exhaust temperature and exhaust heat content are presented. The exhaust temperature is almost always high enough for dissociation to occur, but at lower power outputs, there is only enough exhaust energy for partial dissociation of the methanol.

  5. The electrical conductivity of phospholipid films as an iodine-sensing mechanism.

    Science.gov (United States)

    Jendrasiak, G L; Madison, G E; Smith, R; McIntosh, T J

    1992-01-01

    The d.c. electrical conductivity of dry phospholipid films is increased by some 8-11 orders of magnitude by the adsorption of iodine vapor. The conductivity of these films has been found to increase as a function of iodine 'vapor pressure' and the quantitative relationship between electrical conductivity and the adsorbed iodine has been determined. Films composed of phospholipids with unsaturated hydrocarbon chains are some three orders of magnitude more electrically conductive than are films of phospholipids containing saturated hydrocarbon chains. Optical spectroscopic measurements show the development of absorption bands centered near 294 nm and 365 nm, upon iodine adsorption. These bands are much more intense for unsaturated phospholipids than for saturated ones. X-ray diffraction studies show that exposure to iodine decreases the thickness of phospholipid bilayers containing unsaturated hydrocarbon chains but does not change the thickness of bilayers containing only saturated chains. The electrical response of the lipid films, upon exposure to iodine, suggests their possible use as iodine sensors.

  6. Iodine in soil

    Energy Technology Data Exchange (ETDEWEB)

    Johanson, Karl Johan [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology

    2000-12-01

    A literature study of the migration and the appearance of iodine isotopes in the bio-sphere particularly in soil is presented. Some important papers in the field of iodine appearance in soil and the appearance of {sup 129}I in the surroundings of reprocessing plants are discussed. The most important conclusions are: 1. Iodine binds to organic matter in the soil and also to some oxides of aluminium and iron. 2. If the iodine is not bound to the soil a large fraction of added {sup 129}I is volatilized after a rather short period. 3. The binding and also the volatilisation seems to be due to biological activity in the soil. It may take place within living microorganisms or by external enzymes excreted from microorganisms. 4. Due to variations in the composition of soil there may be a large variation in the distribution of {sup 129}I in the vertical profile of soil - usually most of the {sup 129}I in the upper layer - which also results in large variations in the {sup 129}I uptake to plants.

  7. Iodine in soil

    International Nuclear Information System (INIS)

    Johanson, Karl Johan

    2000-12-01

    A literature study of the migration and the appearance of iodine isotopes in the bio-sphere particularly in soil is presented. Some important papers in the field of iodine appearance in soil and the appearance of 129 I in the surroundings of reprocessing plants are discussed. The most important conclusions are: 1. Iodine binds to organic matter in the soil and also to some oxides of aluminium and iron. 2. If the iodine is not bound to the soil a large fraction of added 129 I is volatilized after a rather short period. 3. The binding and also the volatilisation seems to be due to biological activity in the soil. It may take place within living microorganisms or by external enzymes excreted from microorganisms. 4. Due to variations in the composition of soil there may be a large variation in the distribution of 129 I in the vertical profile of soil - usually most of the 129 I in the upper layer - which also results in large variations in the 129 I uptake to plants

  8. Perchlorate, iodine supplements, iodized salt and breast milk iodine content

    International Nuclear Information System (INIS)

    Kirk, Andrea B.; Kroll, Martina; Dyke, Jason V.; Ohira, Shin-Ichi; Dias, Rukshan A.; Dasgupta, Purnendu K.

    2012-01-01

    This study was undertaken to determine if increasing maternal iodine intake through single dose tablets will decrease breast milk concentrations of the iodine-uptake inhibitor, perchlorate, through competitive inhibition. We also sought to determine if the timing of supplementation influences the fraction of iodine excreted in milk versus urine and to compare the effectiveness of iodized salt as a means of providing iodine to breastfed infants. Thirteen women who did not use supplements, seven of whom used iodized salt and six of whom used non-iodized salt, submitted four milk samples and a 24-h urine collection daily for three days. Women repeated the sampling protocol for three more days during which ∼ 150 μg of iodine were taken in the evening and again for three days with morning supplementation. Samples were analyzed using isotope-dilution inductively-coupled plasma-mass spectrometry for iodine and isotope-dilution ion chromatography-tandem mass spectrometry for perchlorate. No statistically significant differences were observed in milk iodine or perchlorate concentrations during the two treatment periods. Estimated perchlorate intake was above the U.S. National Academy of Sciences suggested reference dose for most infants. Single daily dose iodine supplementation was not effective in decreasing milk perchlorate concentrations. Users of iodized salt had significantly higher iodine levels in milk than non-users. Iodized salt may be a more effective means of iodine supplementation than tablets. - Highlights: ► Estimated infant exposures to perchlorate were, on a μg/kg basis, ∼ 5 × higher than those of mothers. ► Daily supplements are less effective than iodized salt in providing iodine to lactating women. ► Low iodine and high perchlorate in milk may place infants at risk of iodine deficiency.

  9. Perchlorate, iodine supplements, iodized salt and breast milk iodine content

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, Andrea B. [Department of Epidemiology, School of Public Health, University of North Texas Health Sciences Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107 (United States); Kroll, Martina; Dyke, Jason V.; Ohira, Shin-Ichi; Dias, Rukshan A.; Dasgupta, Purnendu K. [Department of Chemistry and Biochemistry, 700 Planetarium Place, University of Texas at Arlington, Arlington, TX 76019 (United States)

    2012-03-15

    This study was undertaken to determine if increasing maternal iodine intake through single dose tablets will decrease breast milk concentrations of the iodine-uptake inhibitor, perchlorate, through competitive inhibition. We also sought to determine if the timing of supplementation influences the fraction of iodine excreted in milk versus urine and to compare the effectiveness of iodized salt as a means of providing iodine to breastfed infants. Thirteen women who did not use supplements, seven of whom used iodized salt and six of whom used non-iodized salt, submitted four milk samples and a 24-h urine collection daily for three days. Women repeated the sampling protocol for three more days during which {approx} 150 {mu}g of iodine were taken in the evening and again for three days with morning supplementation. Samples were analyzed using isotope-dilution inductively-coupled plasma-mass spectrometry for iodine and isotope-dilution ion chromatography-tandem mass spectrometry for perchlorate. No statistically significant differences were observed in milk iodine or perchlorate concentrations during the two treatment periods. Estimated perchlorate intake was above the U.S. National Academy of Sciences suggested reference dose for most infants. Single daily dose iodine supplementation was not effective in decreasing milk perchlorate concentrations. Users of iodized salt had significantly higher iodine levels in milk than non-users. Iodized salt may be a more effective means of iodine supplementation than tablets. - Highlights: Black-Right-Pointing-Pointer Estimated infant exposures to perchlorate were, on a {mu}g/kg basis, {approx} 5 Multiplication-Sign higher than those of mothers. Black-Right-Pointing-Pointer Daily supplements are less effective than iodized salt in providing iodine to lactating women. Black-Right-Pointing-Pointer Low iodine and high perchlorate in milk may place infants at risk of iodine deficiency.

  10. Development of an online method for quantification of maritime molecular iodine and other gaseous iodine containing inorganic compounds

    Science.gov (United States)

    Götz, Sven; Hoffmann, Thorsten

    2014-05-01

    The atmospheric chemistry of iodine is important in multiple ways. The focus lies on the ability to influence the oxidizing capacity of the atmosphere, i.e. by destruction of ozone, and the formation of iodine oxide particles (IOP), i.e. the influence on condensation nuclei (CCN). Using a variation of techniques, like differential optical absorption spectroscopy (DOAS), laser-induced fluorescence (LIF), inductively coupled plasma mass spectrometry (ICP-MS) and atmospheric pressure chemical ionization with tandem mass spectrometry (APCI-MS/MS), the reactive iodine species of atomic iodine (I), molecular iodine (I2), iodine monoxide (IO) and iodine dioxide (OIO) have all been detected in the atmosphere from Antarctica to the equatorial marine boundary layer (MBL). In the past few years there have been active research on IO, especially after revealing significant levels in open ocean measurements, OIO and higher iodine oxides. In addition to atmospheric measurements, significant developments in laboratory kinetics, photochemistry and heterogeneous chemistry of iodine species have been accomplished. [1] Here we introduce an online-method for detecting gaseous molecular iodine and other gaseous iodine-containing inorganic compounds such as HOI, which is a further development of the technique used by Carpenter et al. [2]. The method is based on selective photolytic dissociation of the analytes, followed by oxidization and particle formation of the iodine compounds. The particles are than size-segregated and detected by a scanning mobility particle sizer (SMPS) system. Initial IOP forming is performed in a reaction chamber providing specific wavelengths according to corresponding bond dissociation thresholds. Atmospheric samples can also be pre concentrated by diffusion denuder (with α Cyclodextrin modified and immobilised silica coating) [3-5] and afterwards released by thermodesorption. First attempts of quantification are carried out by external calibration using an

  11. Photodetachment and dissociation dynamics of microsolvated iodide clusters

    Energy Technology Data Exchange (ETDEWEB)

    Piani, G; Becucci, M [European Laboratory for Non-Linear Spectroscopy, Polo Scientifico e Tecnologico Universita di Firenze, via N Carrara 1, 50019 Sesto Fiorentino (Italy); Bowen, M S; Oakman, J; Hu, Q; Continetti, R E [Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0340 (United States)], E-mail: gpiani@lens.unifi.it, E-mail: becucci@lens.unifi.it, E-mail: rcontinetti@ucsd.edu

    2008-11-15

    The properties of anionic clusters I{sup -}X (X=carbon dioxide, water, ammonia, benzene, phenol, aniline and nitrobenzene) and their dissociation dynamics on the neutral potential energy surface following photodetachment (PD) were studied by photoelectron-photofragment coincidence experiments. Different reaction channels were available using 4.82 eV energy photons, leading to production of iodine in the {sup 2}P{sub 3/2} and {sup 2}P{sub 1/2} states and to both stable and dissociating neutral clusters. The partitioning of the available energy strongly favors the electron kinetic energy channel. The kinetic energy release in the fragment channel is rather small and dependent on the potential energy surface on which the process takes place. A multistep dissociative PD process is observed for the iodide-aniline cluster leading to production of zero kinetic energy electrons.

  12. Iodine Status in Pregnant & Breastfeeding Women

    DEFF Research Database (Denmark)

    Andersen, Stine Linding

    Iodine is required for the synthesis of thyroid hormones, which are crucial regulator of early brain development. The source of iodine in the fetus and the breastfed infant is maternal iodine, and adequate iodine intake in pregnant and breastfeeding is of major concern. Severe iodine deficiency can...... cause irreversible brain damage, whereas the consequences of mild to moderate iodine deficiency are less clear. Denmark was previously iodine deficient with regional differences (mild iodine deficiency in East Denmark and moderate iodine deficiency in West Denmark), and also pregnant and breastfeeding...... women suffered from iodine deficiency. A mandatory iodine fortification of household salt and salt used for commercial production of bread was introduced in Denmark in the year 2000. The PhD thesis investigates intake of iodine supplements and urinary iodine status in Danish pregnant and breastfeeding...

  13. Study on iodine-125 production technique

    International Nuclear Information System (INIS)

    Liu Yishu; Han Dongqiao; Lu Changlong; Sun Wenhao; Bao Jianying; Wang Aimin

    1999-11-01

    125 I is produced with natural xenon as target material. The target preparation process is presented. Required xenon is frozen in 100 ml aluminum container by liquid nitrogen and sealed by cold-welding for irradiation in reactor. I - can be adsorbed on Platinum Coated Copper (PCC) in the media of dilute sulfuric acid, pH 3 PCC. In the range of its adsorption capacity, the adsorption efficiency of iodine-125 on PCC is greater than 99.9%. All the radioiodine can be adsorbed on PCC quantifiably and the impurities pass through the column. The elution efficiency of 125 I from PCC column greatly depends on the concentration of eluant NaOH, the amount of adsorbed 125 I - and flow rate as well. The aluminum dissolved from Al container has no apparent effects on both adsorption and elution efficiency. The contents of adsorbent material Cu and Pt is extremely low ( 125 I produced by using PCC chromatographic technique can meet the requirement of RIA kits labelling and other uses

  14. Heterogeneous equilibrium in mplybdenum-iodine system

    International Nuclear Information System (INIS)

    Klinkova, L.A.

    1983-01-01

    Heterogeneous equilibrium in the Mo-J system is studied to reveal regions of existence of molybdenum iodides, is studied. The investigation is performed for atomic ratio I/Mo=0.02-7.5 in the temperature range of 300-1370 K using methods of thermographic, X-ray phase, chemical and optical analyses of phases quenched after isothermal annealing. It is shown that higher molybdenum iodides (Mo1 4 , MoJ 5 , MoJ 6 ) are thermally unstable compounds and exist in the Mo-J system at low temperatures (360-490 K). Above 470 K higher iodides dissociate up to molybdenum triiodide. MoJ 3 under the pressure of iodine vapors is stable up to 970 K. Molybdenum diiodide is the product of triiodide decomposition and forms in the Mo-J system in the 700-1270 K range. At the J/Mo>>3 ratio the product of triiodide decomposition is MoJsub(2.87) which is thermally unstable up to 570 K, while in iodine atmosphere - up to 1170 K

  15. The speciation of iodine in the environment

    International Nuclear Information System (INIS)

    Bulman, R.A.

    1986-01-01

    The speciation of iodine in the environment is discussed under the following topics: (i) sea surface to atmosphere, (ii) chemistry in bulk seawater, (iii) iodine in rocks, (iv) iodine in soils, (v) iodine in plants and (vi) iodine in solidified wastes. (author)

  16. First-Principles Calculations of the Adsorption of Nitromethane and 1,1-Diamino-2,2-dinitroethylene (FOX-7) Molecules on the Al(111) Surface

    National Research Council Canada - National Science Library

    Sorescu, Dan

    2003-01-01

    .... Based on these calculations, we have determined that both dissociative and nondissociative adsorption mechanisms are possible, depending on the molecular orientation and the particular surface sites involved...

  17. Atomic iodine laser

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, G.A.; Gusinow, M.A.; Hays, A.K.; Padrick, T.D.; Palmer, R.E.; Rice, J.K.; Truby, F.K.; Riley, M.E.

    1978-05-01

    The atomic iodine photodissociation laser has been under intensive study for a number of years. The physics associated with this system is now well understood and it is possible to produce a 0.1 nsec (or longer) near-diffraction-limited laser pulse which can be amplified with negligible temporal distortion and little spatial deformation. The output of either a saturated or unsaturated amplifier consists of a high-fidelity near-diffraction-limited, energetic laser pulse. The report is divided into three chapters. Chapter 1 is a survey of the important areas affecting efficient laser operation and summarizes the findings of Chap. 2. Chapter 2 presents detailed discussions and evaluations pertinent to pumps, chemical regeneration, and other elements in the overall laser system. Chapter 3 briefly discusses those areas that require further work and the nature of the work required to complete the full-scale evaluation of the applicability of the iodine photodissociation laser to the inertial confinement program.

  18. The iodine molecule insights into intra- and intermolecular perturbation in diatomic molecules

    CERN Document Server

    Lukashov, Sergey; Pravilov, Anatoly

    2018-01-01

    This book presents experimental and theoretical spectroscopic studies performed over the last 25 years on the iodine molecule’s excited states and their perturbations. It is going to be of interest to researchers who study intra- and intermolecular perturbations in diatomic molecules and more complex systems. The book offers a detailed treatment of the nonadiabatic perturbations of valence, ion pair and Rydberg states induced by intramolecular as well as intermolecular interactions in collisions or in weakly-bound complexes. It also provides an overview of current instrumentation and techniques as well as theoretical approaches describing intra- and intermolecular perturbations. The authors are experts in the use of spectroscopy for the study of intrinsic and collision-induced perturbations in diatomic iodine. They introduced new methods of two- and three-step optical population of the iodine ion-pair states. The iodine molecule has 23 valence states correlating with three dissociation limits, 20 so-called ...

  19. Iodine immobilization in apatites

    International Nuclear Information System (INIS)

    Audubert, F.; Lartigue, J.E.

    2000-01-01

    In the context of a scientific program on long-lived radionuclide conditioning, a matrix for iodine 129 immobilization has been studied. A lead vanado-phosphate apatite was prepared from the melt of lead vanado-phosphate Pb 3 (VO 4 ) 1.6 (PO 4 ) 0.4 and lead iodide PbI 2 in stoichiometric proportions by calcination at 700 deg. C during 3 hours. Natural sintering of this apatite is not possible because the product decomposition occurs at 400 deg. C. Reactive sintering is the solution. The principle depends on the coating of lead iodide with lead vanado-phosphate. Lead vanado-phosphate coating is used as iodo-apatite reactant and as dense covering to confine iodine during synthesis. So the best condition to immobilize iodine during iodo-apatite synthesis is a reactive sintering at 700 deg. C under 25 MPa. We obtained an iodo-apatite surrounded with dense lead vanadate. Leaching behaviour of the matrix synthesized by solid-solid reaction is under progress in order to determine chemical durability, basic mechanisms of the iodo-apatite alteration and kinetic rate law. Iodo-apatite dissolution rates were pH and temperature dependent. We obtained a rate of 2.5 10 -3 g.m -2 .d -1 at 90 deg. C in initially de-ionised water. (authors)

  20. Immobilization of iodine in concrete

    International Nuclear Information System (INIS)

    Clark, W.E.; Thompson, C.T.

    1977-01-01

    A method for immobilizing fission product radioactive iodine recovered from irradiated nuclear fuel comprises combining material comprising water, Portland cement and about 3 to 20 wt percent iodine as Ba(IO 3 ) 2 to provide a fluid mixture and allowing the fluid mixture to harden, said Ba(IO 3 ) 2 comprising said radioactive iodine. An article for solid waste disposal comprises concrete prepared by this method. 10 claims, 2 figures

  1. Iodine neutron capture therapy

    Science.gov (United States)

    Ahmed, Kazi Fariduddin

    A new technique, Iodine Neutron Capture Therapy (INCT) is proposed to treat hyperthyroidism in people. Present thyroid therapies, surgical removal and 131I treatment, result in hypothyroidism and, for 131I, involve protracted treatment times and excessive whole-body radiation doses. The new technique involves using a low energy neutron beam to convert a fraction of the natural iodine stored in the thyroid to radioactive 128I, which has a 24-minute half-life and decays by emitting 2.12-MeV beta particles. The beta particles are absorbed in and damage some thyroid tissue cells and consequently reduce the production and release of thyroid hormones to the blood stream. Treatment times and whole-body radiation doses are thus reduced substantially. This dissertation addresses the first of the several steps needed to obtain medical profession acceptance and regulatory approval to implement this therapy. As with other such programs, initial feasibility is established by performing experiments on suitable small mammals. Laboratory rats were used and their thyroids were exposed to the beta particles coming from small encapsulated amounts of 128I. Masses of 89.0 mg reagent-grade elemental iodine crystals have been activated in the ISU AGN-201 reactor to provide 0.033 mBq of 128I. This activity delivers 0.2 Gy to the thyroid gland of 300-g male rats having fresh thyroid tissue masses of ˜20 mg. Larger iodine masses are used to provide greater doses. The activated iodine is encapsulated to form a thin (0.16 cm 2/mg) patch that is then applied directly to the surgically exposed thyroid of an anesthetized rat. Direct neutron irradiation of a rat's thyroid was not possible due to its small size. Direct in-vivo exposure of the thyroid of the rat to the emitted radiation from 128I is allowed to continue for 2.5 hours (6 half-lives). Pre- and post-exposure blood samples are taken to quantify thyroid hormone levels. The serum T4 concentration is measured by radioimmunoassay at

  2. Effect of carbon dioxide on the rate of iodine vapor absorption by aqueous solution of sodium hydroxide

    International Nuclear Information System (INIS)

    Eguchi, Wataru; Adachi, Motonari; Miyake, Yoshikazu

    1978-01-01

    There is always carbon dioxide in the atmosphere as an impurity. Since this is an acid gas similar to iodine, each absorption rate seems to be affected by the other due to the coexistence of these two. Experiments have been conducted to clarify the absorption rate and absorption mechanism of iodine in the simultaneous absorption of iodine and carbon dioxide. Carbon dioxide coexisting with gas phases as an impurity decreases the absorption rate of iodine in the removal by washing with water of iodine mixed in the air. The first cause of this is that the diffusion coefficient of iodine in gas phase decreases with the carbon dioxide content in the gas phase. The second cause is that coexistent carbon dioxide is an acid gas, dissociates by dissolving into the absorbing solution, increases hydrogen ion concentration together with the formation of negative ions of bicarbonate and carbonate, and reduces hydroxyl ion concentration as a result. It is more important that existence of iodine has a catalytic effect to the rate of basic catalytic hydrolysis of carbon dioxide simultaneously dissolved in water phase, and accelerates this reaction rate. The mechanism of catalytic effect of iodine for the hydrolysis of carbon dioxide can not be clarified in detail only by this experiment, but the simultaneous absorption rate of iodine and carbon dioxide can be explained satisfactorily. (Wakatsuki, Y

  3. Iodine removal from a gas phase

    International Nuclear Information System (INIS)

    Vikis, A. Ch.

    1982-01-01

    Iodine, e.g. radioactive iodine, present as one or more organic iodides, optionally with elemental iodine, in a gas phase (e.g. air) are removed by photochemically decomposing the organic iodides to elemental iodine, reacting the iodine produced, and any initially present with excess ozone, preferably photochemically produced in situ in the gas phase to produce solid iodine oxides, and removing the solid oxides from the gas phase. (author)

  4. Iodine removal from a gas phase

    International Nuclear Information System (INIS)

    Vikis, A.C.

    1984-01-01

    Iodine, e.g. radioactive iodine, present as one or more organic iodides, optionally with elemental iodine, in a gas phase (e.g. air) are removed by photochemically decomposing the organic iodides to elemental iodine, reacting the iodine produced, and any initially present with excess ozone, preferably photochemically produced in situ in the gas phase to produce solid iodine oxides, and removing the solid oxides from the gas phase

  5. 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.

  6. Regeneration of the iodine isotope-exchange efficiency for nuclear-grade activated carbons

    International Nuclear Information System (INIS)

    Deitz, V.R.

    1985-01-01

    The removal of radioactive iodine from air flows passing through impregnated activated carbons depends on a minimum of three distinguishable reactions: (1) adsorption on the carbon networks of the activated carbons, (2) iodine isotope exchange with impregnated iodine-127, and (3) chemical combination with impregnated tertiary amines when present. When a carbon is new, all three mechanisms are at peak performance and it is not possible to distinguish among the three reactions by a single measurement; the retention of methyl iodide-127 is usually equal to the retention of methyl iodide-131. After the carbon is placed in service, the three mechanisms of iodine removal are degraded by the contaminants of the air at different rates; the adsorption process degrades faster than the other two. This behavior will be shown by comparisons of methyl iodide-127 and methyl iodide-131 penetration tests. It was found possible to regenerate the iodine isotope-exchange efficiency by reaction with airborne chemical reducing agents with little or no improvement in methyl iodine-127 retention. Examples will be given of the chemical regeneration of carbons after exhaustion with known contaminants as well as for many carbons removed from nuclear power operations. The depth profile of methyl iodide-131 penetration was determined in 2-inch deep layers before and after chemical treatments

  7. Controlling Solid–Liquid Conversion Reactions for a Highly Reversible Aqueous Zinc–Iodine Battery

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Huilin; Li, Bin; Mei, Donghai; Nie, Zimin; Shao, Yuyan; Li, Guosheng; Li, Xiaohong S.; Han, Kee Sung; Muller, Karl T.; Sprenkle, Vincent L.; Liu, Jun

    2017-10-30

    Aqueous rechargeable batteries are desirable for many energy storage applications due to their low cost and high safety. However, low capacity and short cycle life are the significant obstacles to their practical applications. Here, we demonstrate a highly reversible aqueous zinc-iodine battery using encapsulated iodine in microporous active carbon fibers (ACFs) as cathode materials through the rational control of solid-liquid conversion reactions. The experiments and density function theory (DFT) calculations were employed to investigate the effects of solvents and properties of carbon hosts, e.g. pore size, surface chemistries, on the adsorption of iodine species. The rational manipulation of the competition between the adsorption in carbon and solvation in electrolytes for iodine species is responsible for the high reversibility and cycling stability. The zinc-iodine batteries deliver a high capacity of 180 mAh g-1 at 1C and a stable cycle life over 3000 cycles with ~90% capacity retention as well as negligible self-discharge. We believe the principles for stabilizing the zinc-iodine system could provide new insight into conversion systems such as Li-S systems.

  8. The Status of Iodine Nutrition and Iodine Deficiency Disorders ...

    African Journals Online (AJOL)

    Background: Iodine deficiency disorders are serious public health problems in Ethiopia. The aim of this study was to measure the prevalence and severity of iodine deficiency disorders among school children in Metekel Zone. Methods: A cross-sectional school based descriptive study was conducted between February 2011 ...

  9. Modelling the chemistry of iodine

    International Nuclear Information System (INIS)

    Paquette, J.

    1989-01-01

    We have assembled a kinetic model, based on elementary chemical reactions, that describes the chemical behaviour of iodine in aqueous solution as a function of time and various parameters such as pH, concentration and radiation field. The model is conceptually divided into six section: aqueous iodine chemistry, aqueous organic iodide chemistry, water radiolysis, radiolysis of iodine solutions, radiolysis of organic iodide solutions and mass transfer. The model indicates that, in the absence of a radiation field, the rate of production of volatile iodine species is controlled by the rate of oxidation of the iodide ion. The volatile iodine species are dominated by organic iodides if organic impurities are present. The single most important parameter controlling iodine volatility is the pH of the solution; high pH values tend to minimize iodine volatility. In the presence of a radiation field, the volatility of iodine is controlled by the radiation-induced oxidation of the iodide ion. Again, iodine volatility is dominated by organic iodides if organic impurities are present. High pH values minimize iodine volatility. A sensitivity analysis has been performed on some sections of the model to identify reactions to which the volatility of iodine is most sensitive. In the absence of a radiation field, the volatility is most sensitive, first, to the rate of oxidation of the iodide ion, and, second, to the rate of mass transfer of volatile species between the aqueous and the gaseous phases. This approach should be useful in identifying reactions for which accurate rate constants are required and in decreasing the complexity of the model. 37 refs

  10. Radioactive Iodine and Krypton Control for Nuclear Fuel Reprocessing Facilities

    Directory of Open Access Journals (Sweden)

    Nick R. Soelberg

    2013-01-01

    Full Text Available The removal of volatile radionuclides generated during used nuclear fuel reprocessing in the US is almost certain to be necessary for the licensing of a reprocessing facility in the US. Various control technologies have been developed, tested, or used over the past 50 years for control of volatile radionuclide emissions from used fuel reprocessing plants. The US DOE has sponsored, since 2009, an Off-gas Sigma Team to perform research and development focused on the most pressing volatile radionuclide control and immobilization problems. In this paper, we focus on the control requirements and methodologies for 85Kr and 129I. Numerous candidate technologies have been studied and developed at laboratory and pilot-plant scales in an effort to meet the need for high iodine control efficiency and to advance alternatives to cryogenic separations for krypton control. Several of these show promising results. Iodine decontamination factors as high as 105, iodine loading capacities, and other adsorption parameters including adsorption rates have been demonstrated under some conditions for both silver zeolite (AgZ and Ag-functionalized aerogel. Sorbents, including an engineered form of AgZ and selected metal organic framework materials (MOFs, have been successfully demonstrated to capture Kr and Xe without the need for separations at cryogenic temperatures.

  11. Iodine-Catalyzed Polysaccharide Esterification

    Science.gov (United States)

    A review is provided of the recent reports to use iodine-catalyzed esterification reaction to produce esters from polysaccharides. The process entails reaction of the polysaccharide with an acid anhydride in the presence of a catalytic level of iodine, and in the absence of additional solvents. T...

  12. Mechanism of pulse discharge production of iodine atoms from CF3I molecules for a chemical oxygen-iodine laser

    International Nuclear Information System (INIS)

    Kochetov, I V; Napartovich, A P; Vagin, N P; Yuryshev, N N

    2009-01-01

    The pulsed chemical oxygen-iodine laser (COIL) development is aimed at many new applications. Pulsed electric discharge is most effective in turning COIL operation into the pulse mode by instant production of iodine atoms. A numerical model is developed for simulations of the pulsed COIL initiated by an electric discharge. The model comprises a system of kinetic equations for neutral and charged species, electric circuit equation, gas thermal balance equation and the photon balance equation. Reaction rate coefficients for processes involving electrons are found by solving the electron Boltzmann equation, which is re-calculated in a course of computations when plasma parameters changed. The processes accounted for in the Boltzmann equation include excitation and ionization of atoms and molecules, dissociation of molecules, electron attachment processes, electron-ion recombination, electron-electron collisions, second-kind collisions and stepwise excitation of molecules. The last processes are particularly important because of a high singlet oxygen concentration in gas flow from the singlet oxygen chemical generator. Results of numerical simulations are compared with experimental laser pulse waveforms. It is concluded that there is satisfactory agreement between theory and the experiment. The prevailing mechanism of iodine atom formation from the CF 3 I donor in a very complex kinetic system of the COIL medium under pulse discharge conditions, based on their detailed numerical modelling and by comparing these results both with experimental results of other authors and their own experiments, is established. The dominant iodine atom production mechanism for conditions under study is the electron-impact dissociation of CF 3 I molecules. It was proved that in the conditions of the experiment the secondary chemical reactions with O atoms play an insignificant role.

  13. Dissociative symptoms in kleptomania.

    Science.gov (United States)

    Grant, Jon E

    2004-02-01

    Many patients with kleptomania report an altered state of consciousness during acts of theft. The purpose of this investigation was to clarify a possible link between dissociation and kleptomania, a disabling disorder whose phenomenology remains understudied. 26 adult outpatients who met DSM-IV criteria for kleptoania were administered the Dissociative Experiences Scale and compared to 22 normal controls. The patients with kleptomania had scores that differed significantly from those reported by normal controls. There were no statistically significant differences by sex. Because kleptomania patients seeking treatment with medication may differ from others with kleptomania, further studies are needed.

  14. Van de Graaff Experiments: Mo Redox Chemistry and Iodine Speciation

    Energy Technology Data Exchange (ETDEWEB)

    Youker, A. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Krebs, J. F. [Argonne National Lab. (ANL), Argonne, IL (United States); Hebden, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Quigley, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Stepinski, D. [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, G. F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2012-09-27

    Argonne National Laboratory (Argonne) is assisting Morgridge Institute for Research (MIR) in its efforts to develop SHINE, which is an accelerator-driven process that will use a uranyl-sulfate solution for the production of Mo-99. Mo will be separated from an irradiated uranyl-sulfate solution using a titania sorbent; however, the highly reducing environment may lead to Mo reduction. If Mo is reduced to Mo(IV) or Mo(V), its adsorption and/or recovery will decrease, and an oxidizing agent will be required to ensure that Mo is present as Mo(VI). Another concern for SHINE is related to the speciation of iodine during irradiation, cooling, column loading and stripping, and Mo-99 purification. Both Mo oxidation state and iodine speciation experiments were performed using a Van de Graaff generator as a source of radiation. Initial results indicate that Mo may be reduced during irradiation because low Mo recoveries were obtained for three separate column experiments performed using irradiated solutions. The results were complicated, however, because nearly 60 min passed between the end of irradiation and the initiation of column experiments, and high back pressures were observed for two out of the three experiments. This also made it difficult to determine what variable caused low Mo recovery. Radiation dose and starting iodine species had no effect on overall iodine speciation, and iodide was the predominant species for all tests.

  15. Breastfeeding and maternal and infant iodine nutrition.

    Science.gov (United States)

    Azizi, Fereidoun; Smyth, Peter

    2009-05-01

    The aim of this review is to explore information available regarding iodine secretion in milk, both mothers and infants iodine nutrition during breastfeeding and to make recommendations for appropriate iodine supplementation during lactation. MEDLINE was queried for studies between 1960 and 2007 that included lactation and breastfeeding with iodine and iodine deficiency. Studies were selected if they studied (i) Secretion of iodine in breast milk; (ii) breastfeeding and iodine nutrition; (iii) factors affecting maternal iodine metabolism and (iv) recommendations for iodine supplementation during breastfeeding. Thirty-six articles met the selection criteria. The iodine content of breast milk varies with dietary iodine intake, being lowest in areas of iodine deficiency with high prevalence of goitre. Milk iodine levels are correspondingly higher when programs of iodine prophylaxis such as salt iodization or administration of iodized oil have been introduced. The small iodine pool of the neonatal thyroid turns over very rapidly and is highly sensitive to variations in dietary iodine intake. Expression of the sodium iodide symporter is up-regulated in the lactating mammary gland which results in preferential uptake of iodide. In areas of iodine sufficiency breast milk iodine concentration should be in the range of 100-150 microg/dl. Studies from France, Germany, Belgium, Sweden, Spain, Italy, Denmark, Thailand and Zaire have shown breast milk concentrations of nutrition. The current WHO/ICCIDD/UNICEF recommendation for daily iodine intake (250 microg for lactating mothers) has been selected to ensure that iodine deficiency dose not occur in the postpartum period and that the iodine content of the milk is sufficient for the infant's iodine requirement.

  16. Hydrogen adsorption on bimetallic PdAu(111) surface alloys

    DEFF Research Database (Denmark)

    Takehiro, Naoki; Liu, Ping; Bergbreiter, Andreas

    2014-01-01

    The adsorption of hydrogen on structurally well defined PdAu-Pd(111) monolayer surface alloys was investigated in a combined experimental and theoretical study, aiming at a quantitative understanding of the adsorption and desorption properties of individual PdAu nanostructures. Combining...... the structural information obtained by high resolution scanning tunneling microscopy (STM), in particular on the abundance of specific adsorption ensembles at different Pd surface concentrations, with information on the adsorption properties derived from temperature programmed desorption (TPD) spectroscopy...... and high resolution electron energy loss spectroscopy (HREELS) provides conclusions on the minimum ensemble size for dissociative adsorption of hydrogen and on the adsorption energies on different sites active for adsorption. Density functional theory (DFT) based calculations give detailed insight...

  17. Antineoplastic mechanisms of Iodine in cancers that take up Iodine

    Directory of Open Access Journals (Sweden)

    Carmen Aceves

    2015-12-01

    Full Text Available Purpose: In addition to being a component of thyroid hormone (TH, iodine can be an antioxidant as well as an antiproliferative and differentiation agent that helps to maintain the integrity of several organs with the ability to take up iodine.Methods and Results: Studies from our laboratory shown that in preclinical (cell culture, induced animal cancer and xenographs and clinical studies (mammary cancer protocol, molecular iodine (I2 supplementation exerts suppressive effects on implantation, development, and progression of cancer neoplasias. These effects can be mediated by a variety of mechanisms and pathways, including direct actions, in which the oxidized iodine modulates the immune/tumor response and through iodolipid formation and the activation of peroxisome proliferator-activated receptors type gamma (PPARγ triggering apoptotic and/or differentiation pathways.Conclusion: The absence of side effects and the easy availability and handling of I2 have allowed the establishment of clinical protocols to utilize I2 supplementation as an adjuvant in therapies against cancers that take up iodine.-----------------------------------------Cite this article as:  Aceves C, Anguiano B. Antineoplastic mechanisms of Iodine in cancers that take up Iodine. Int J Cancer Ther Oncol 2015; 3(4:3401.[This abstract was presented at the BIT’s 8th Annual World Cancer Congress, which was held from May 15-17, 2015 in Beijing, China.

  18. Weakly-bound adsorption states and low-temperature adsorption kinetiks of oxygen on tungsten (100) and (110) faces

    International Nuclear Information System (INIS)

    Zhukov, V.V.; Osovskij, V.D.; Ptushnikov, Yu.G.; Sukretnyj, V.G.; Chujkov, B.A.

    1986-01-01

    A molecular beam technique with an effusion source operating at T=200 K is used to study the adsorption interaction of oxygen with W(100) and (110) faces in the range of the simple temperatures from 5 to 340 K. Three weakly-bound adsorption states of oxygen are detected corresponding to adsorption in the second, third and forth monolayer. These states are characterized by adsorption energies of 0.13, 0.08 and 0.07 eV and desorption temperatures of 45, 27 and 25 K, respectively. The kinetics of filling of these states is almost similar for both faces, whereas the adsorption kinetics in the first monolayer is essentially different. A dissociative nature of adsorption at T >or approx. 5 K and a jump migration mechanism of the admolecules in the precursor state to the stationary adsorption sites are suggested

  19. Dissociation and psychosis in dissociative identity disorder and schizophrenia.

    Science.gov (United States)

    Laddis, Andreas; Dell, Paul F

    2012-01-01

    Dissociative symptoms, first-rank symptoms of schizophrenia, and delusions were assessed in 40 schizophrenia patients and 40 dissociative identity disorder (DID) patients with the Multidimensional Inventory of Dissociation (MID). Schizophrenia patients were diagnosed with the Structured Clinical Interview for the DSM-IV Axis I Disorders; DID patients were diagnosed with the Structured Clinical Interview for DSM-IV Dissociative Disorders-Revised. DID patients obtained significantly (a) higher dissociation scores; (b) higher passive-influence scores (first-rank symptoms); and (c) higher scores on scales that measure child voices, angry voices, persecutory voices, voices arguing, and voices commenting. Schizophrenia patients obtained significantly higher delusion scores than did DID patients. What is odd is that the dissociation scores of schizophrenia patients were unrelated to their reports of childhood maltreatment. Multiple regression analyses indicated that 81% of the variance in DID patients' dissociation scores was predicted by the MID's Ego-Alien Experiences Scale, whereas 92% of the variance in schizophrenia patients' dissociation scores was predicted by the MID's Voices Scale. We propose that schizophrenia patients' responses to the MID do not index the same pathology as do the responses of DID patients. We argue that neither phenomenological definitions of dissociation nor the current generation of dissociation instruments (which are uniformly phenomenological in nature) can distinguish between the dissociative phenomena of DID and what we suspect are just the dissociation-like phenomena of schizophrenia.

  20. Iodine content of infant formulas and iodine intake of premature babies: high risk of iodine deficiency.

    Science.gov (United States)

    Ares, S; Quero, J; Durán, S; Presas, M J; Herruzo, R; Morreale de Escobar, G

    1994-11-01

    As part of a study of thyroid function in premature babies, the iodine content of their mothers' breast milk, that of 32 formulas from different brands used in Spain, and that of 127 formulas used in other countries was determined. Breast milk contained more iodine--mean (SEM) 10 (1) microgram/dl--than most of the formulas, especially those for premature babies. Iodine intakes were therefore below the recommended daily amount (RDA) for newborns: babies of 27-30 weeks' gestational age took 3.1 (1.1) micrograms/day at 5 days of age and 29.8 (2.7) micrograms by 2 months of age. This problem is not exclusive to Spanish premature babies as the iodine content of many of the formulas on sale in other countries was also inadequate. It is concluded that preterm infants who are formula fed are at high risk of iodine deficiency.

  1. Dissociative Identity Disorder

    Science.gov (United States)

    Schmidt, Tom

    2007-01-01

    Few psychological disorders in the Diagnostic Statistical Manual have generated as much controversy as Dissociative Identity Disorder (DID). For the past 35 years diagnoses of DID, previously referred to as Multiple Personality Disorder (MPD), have increased exponentially, causing various psychological researchers and clinicians to question the…

  2. Inter-row Adsorption Configuration and Stability of Threonine Adsorbed on the Ge(100) Surfaces

    International Nuclear Information System (INIS)

    Lee, Myungjin; Park, Youngchan; Jeong, Hyuk; Lee, Hangil

    2013-01-01

    The adsorption structures of threonine on the Ge(100) surface were investigated using core-level photoemission spectroscopy (CLPES) in conjunction with density functional theory (DFT) calculations. CLPES measurements were performed to identify the experimentally preferred adsorption structure. The preferred structure indicated the relative reactivities of the carboxyl and hydroxymethyl groups as electron donors to the Ge(100) surface during adsorption. The core-level C 1s, N 1s, and O 1s CLPES spectra indicated that the carboxyl oxygen competed more strongly with the hydroxymethyl oxygen during the adsorption reaction. Three among six possible adsorption structures were identified as energetically favorable using DFT calculation methods that considered the inter- and intra-bonding configurations upon adsorption onto the Ge(100) surface. These structures were O-H dissociated N dative inter bonding, O-H dissociated N dative intra bonding, O-H dissociation bonding. One of the adsorption structures: O-H dissociated N dative inter bonding was predicted to be stable in light of the transition state energies. We thus confirmed that the most favorable adsorption structure is the O-H dissociated N dative-inter bonding structure using CLPES and DFT calculation

  3. Iodine in the environment revisited

    International Nuclear Information System (INIS)

    Christiansen, J.V.; Carlsen, L.

    1989-05-01

    The report gives an overview of the environmental cycle of iodine, especially focusing on the possible reactions being responsible for the retention of iodine in the terrestrial environment. During the last two decades evidence for the presence of iodine in soil as organically bound has been presented. The major part of inorganic iodine in the terrestrial environment will, under physical and chemical conditions normally prevailing, exist as iodide. No evidence for a direct reaction between iodide and organic material has been presented, whereas strong support for the engagement of microbial activity in the formation of organic iodine compounds in soil has been obtained. Incorporation of iodine in humic substances as a result of enzymatic catalysis, involving an enzyme of the perozidase group apperas reasonable. It is concluded that microbiological activity involving extracellular enzymes most probably is responsible for the possible retention of iodine in the terrestrial environment. It is suggested that these reactions in detail should be studied experimentally. (author) 3 tabs., 2 ills., 51 refs

  4. 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

  5. Iodine deficiency and nutrition in Scandinavia

    DEFF Research Database (Denmark)

    Manousou, Sofia; Dahl, Lisbeth; Heinsbaek Thuesen, Betina

    2017-01-01

    Iodine nutrition is a result of geological conditions, iodine fortification and monitoring strategies within a country together with the dietary habits of the population. This review summarizes the basis for the current iodine situation in the Scandinavian countries in order to identify gaps...... strategies have been used in Scandinavia to improve iodine nutrition. The major source of iodine is iodized salt in Sweden and from milk and dairy products in Norway. In Denmark, drinking water, milk, dairy products and iodized salt used in commercial production of bread are the important sources of iodine....... The current iodine status in Scandinavia is not optimal and action is ongoing to increase iodination in Denmark, where there is mild iodine deficiency in the general population. Data from all three countries indicate insufficient iodine nutrition during pregnancy and there is a need for data from children...

  6. Three dimensions of dissociative amnesia.

    Science.gov (United States)

    Dell, Paul F

    2013-01-01

    Principal axis factor analysis with promax rotation extracted 3 factors from the 42 memory and amnesia items of the Multidimensional Inventory of Dissociation (MID) database (N = 2,569): Discovering Dissociated Actions, Lapses of Recent Memory and Skills, and Gaps in Remote Memory. The 3 factors' shared variance ranged from 36% to 64%. Construed as scales, the 3 factor scales had Cronbach's alpha coefficients of .96, .94, and .93, respectively. The scales correlated strongly with mean Dissociative Experiences Scale scores, mean MID scores, and total scores on the Structured Clinical Interview for DSM-IV Dissociative Disorders-Revised (SCID-D-R). What is interesting is that the 3 amnesia factors exhibited a range of correlations with SCID-D-R Amnesia scores (.52, .63, and .70, respectively), suggesting that the SCID-D-R Amnesia score emphasizes gaps in remote memory over amnesias related to dissociative identity disorder. The 3 amnesia factor scales exhibited a clinically meaningful pattern of significant differences among dissociative identity disorder, dissociative disorder not otherwise specified-1, dissociative amnesia, depersonalization disorder, and nonclinical participants. The 3 amnesia factors may have greater clinical utility for frontline clinicians than (a) amnesia as discussed in the context of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, nosology of the dissociative disorders or (b) P. Janet's (1893/1977 ) 4-fold classification of dissociative amnesia. The author recommends systematic study of the phenomenological differences within specific dissociative symptoms and their differential relationship to specific dissociative disorders.

  7. Adsorption of Acetic Acid, Cadmium ions, Lead ions and Iodine ...

    African Journals Online (AJOL)

    This paper presents the performance evaluation of locally prepared activated carbon from rice husk and saw dust. The raw materials were carbonized at different temperatures (600-800oC) using sodium hydroxide (NaOH) as the activating agent. The study includes moisture content determination of the raw materials used ...

  8. Radiochemistry of iodine

    Energy Technology Data Exchange (ETDEWEB)

    Kahn, M.; Kleinberg, J.

    1977-09-01

    The preparation of isotopes of the element, with selected procedures for its determination in or separation from various media is described along with the separating of iodine species from each other. Each part of the introductory section is referenced separately from the remainder of the monograph. For the preparative and analytical sections there is an extensive, indexed bibliography which was developed from the indexes of Volumes 19 to 30 inclusive (1965-1974) of Nuclear Science Abstracts (NSA). From these indexes the NSA abstracts of possible pertinent references were selected for examination and a choice was made of those references which were to be included in the bibliography. The bibliography has both primary and secondary references. Although the monograph does not cover hot atom chemistry, the kinetics of exchange reactions, decay schemes, or physiological applications, papers in these areas were examined as possible sources of useful preparative and analytical procedures. (JRD)

  9. Current iodinated contrast media

    International Nuclear Information System (INIS)

    Stacul, F.

    2001-01-01

    The number of scientific papers on iodinated contrast media is declining. Indeed, comparative trials between high-osmolality and low-osmolality agents largely showed the higher safety and tolerability of the latter, and this is no longer a matter of discussion. Only financial constraints could prevent a total conversion to low-osmolality agents. Research comparing low-osmolality (nonionic monomers, ionic dimer) and iso-osmolality contrast media (nonionic dimers) are still ongoing. Both classes of nonionic compounds proved safer than the ionic dimer. The relative merits of nonionic monomers and nonionic dimers are a matter for debate, and criteria for a selective use of different agents for different procedures could be discussed. (orig.)

  10. Radiochemistry of iodine

    International Nuclear Information System (INIS)

    Kahn, M.; Kleinberg, J.

    1977-09-01

    The preparation of isotopes of the element, with selected procedures for its determination in or separation from various media is described along with the separating of iodine species from each other. Each part of the introductory section is referenced separately from the remainder of the monograph. For the preparative and analytical sections there is an extensive, indexed bibliography which was developed from the indexes of Volumes 19 to 30 inclusive (1965-1974) of Nuclear Science Abstracts (NSA). From these indexes the NSA abstracts of possible pertinent references were selected for examination and a choice was made of those references which were to be included in the bibliography. The bibliography has both primary and secondary references. Although the monograph does not cover hot atom chemistry, the kinetics of exchange reactions, decay schemes, or physiological applications, papers in these areas were examined as possible sources of useful preparative and analytical procedures

  11. Innovative nanoporous carbons with ultrahigh uptakes for capture and reversible storage of CO{sub 2} and volatile iodine

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Hanxue; La, Peiqing [College of Petrochemical Technology, Lanzhou University of Technology, Langongping Road 287, Lanzhou 730050, PR China (China); Yang, Ruixia [State Key Laboratory of Molecular Reaction Dynamics, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Zhu, Zhaoqi; Liang, Weidong; Yang, Baoping [College of Petrochemical Technology, Lanzhou University of Technology, Langongping Road 287, Lanzhou 730050, PR China (China); Li, An, E-mail: lian2010@lut.cn [College of Petrochemical Technology, Lanzhou University of Technology, Langongping Road 287, Lanzhou 730050, PR China (China); Deng, Weiqiao, E-mail: dengwq@dicp.ac.cn [State Key Laboratory of Molecular Reaction Dynamics, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)

    2017-01-05

    Highlights: • Cigarette filter was utilized to prepare highly porous carbons as super absorbents. • The porous carbons exhibit excellent iodine uptake. • The porous carbons show high CO{sub 2} adsorption capacity of 6.0 mmol g{sup −1} at 273 K. - Abstract: Porous carbons as solid-state adsorbents have recently attracted considerable interest in the areas of storage and capture of CO{sub 2} as well as the adsorption of radioactive matters. In this work, cigarette butts, one kind of common wastes referring to the filters, were utilized to prepare highly porous carbons by KOH activation in argon atmosphere. The resulting porous carbon shows a high specific surface area of up to 2751 m{sup 2} g{sup −1} with abundant micropores. The resulting porous carbon exhibits excellent iodine uptake of 262 wt% and high CO{sub 2} adsorption capacity of 6.0 mmol g{sup −1} at ambient pressure and 273 K, which both are among the highest values reported to date. Given these excellent iodine uptake, CO{sub 2} adsorption capacity, ease of preparation as well as good physiochemical stability, the porous carbons derived from cigarette butts show great potential in the reversible adsorption of radioactive iodine and CO{sub 2}.

  12. Iodine laser program: SAIL-1

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The iodine laser is the most highly developed near-infrared gas laser available for large-scale laser development. Its fast-repetition-rate potential and prospects for improvements in efficiency make it a primary laser candidate to meet mid-term laser-fusion requirements. It may have adequate efficiency for commercial laser-fusion applications in a hybrid fission/fusion reactor, for fusion-fuel breeding and for laser-fusion power generation using complex pellets. Research progress is reported on: (1) SAIL-1; (2) iodine laser-code development; (3) collision and radiation coupling for iodine atoms; (4) development of multilevel Block-Maxwell equations; (5) approximations for iodine amplifiers; and (6) studies based on the ISTAR code

  13. Immobilization of iodine in concrete

    Science.gov (United States)

    Clark, Walter E.; Thompson, Clarence T.

    1977-04-12

    A method for immobilizing fission product radioactive iodine recovered from irradiated nuclear fuel comprises combining material comprising water, Portland cement and about 3-20 wt. % iodine as Ba(IO.sub.3).sub.2 to provide a fluid mixture and allowing the fluid mixture to harden, said Ba(IO.sub.3).sub.2 comprising said radioactive iodine. An article for solid waste disposal comprises concrete prepared by this method. BACKGROUND OF THE INVENTION This invention was made in the course of, or under a contract with the Energy Research and Development Administration. It relates in general to reactor waste solidification and more specifically to the immobilization of fission product radioactive iodine recovered from irradiated nuclear fuel for underground storage.

  14. [Iodine excess induced thyroid dysfunction].

    Science.gov (United States)

    Egloff, Michael; Philippe, Jacques

    2016-04-20

    The principle sources of iodine overload, amiodarone and radiologic contrast media, are frequently used in modern medicine. The thyroid gland exerts a protective effect against iodine excess by suppressing iodine internalization into the thyrocyte and iodine organification, the Wolff-Chaikoff effect. Insufficiency of this effect or lack of escape from it leads to hypo- or hyperthyroidism respectively. Amiodarone induced thyrotoxicosis is a complex condition marked by two different pathophysiological mechanisms with different treatments. Thyroid metabolism changes after exposure to radiologic contrast media are frequent, but they rarely need to be treated. High risk individuals need to be identifed in order to delay the exam or to monitor thyroid function or apply prophylactic measures in selected cases.

  15. Thyroidectomy: is Lugol's iodine necessary?

    Science.gov (United States)

    Coyle, P J; Mitchell, J E

    1982-01-01

    In a randomised controlled clinical trial of Lugol's iodine against placebo in 44 patients undergoing thyroidectomy we have failed to show any benefit in terms of reduced bleeding or operative facility after using iodide solution. PMID:7051944

  16. Thyroidectomy: is Lugol's iodine necessary?

    OpenAIRE

    Coyle, P J; Mitchell, J E

    1982-01-01

    In a randomised controlled clinical trial of Lugol's iodine against placebo in 44 patients undergoing thyroidectomy we have failed to show any benefit in terms of reduced bleeding or operative facility after using iodide solution.

  17. Environmental behavior of technetium-99 and iodine-129

    International Nuclear Information System (INIS)

    Garland, T.R.; Schreckhise, R.G.

    1982-01-01

    The environmental behavior of technetium-99 and iodine-129 was once thought to be similar, particularly with respect to their soil solubility and biological interactions. Over the past several years, the comparative behavior of these two anions has been studied with respect to their fate in natural environments (both aquatic and terrestrial). The mechanisms studied include physical, chemical and biological parameters that account for differences in soil behavior, cycling between soil and/or air to vegetation, adsorption and metabolism in plants, and their availability and fate following ingestion by animals

  18. Iodine recovery from brine solutions

    Energy Technology Data Exchange (ETDEWEB)

    Weetall, H.H.; Hertl, W.

    1985-10-15

    Iodine has been produced by the reaction of iodide with hydrogen peroxide in the presence of the catalyst ferrous sulfate. The presence of high concentrations of chloride or bromide in both natural and synthetic brines have no effect on the reaction specificity or kinetics. This approach is potentially a less caustic method for the recovery of iodine from brine as compared to the most commonly used chlorine displacement methods.

  19. Milk Iodine Content in Slovakia

    Directory of Open Access Journals (Sweden)

    I. Paulíková

    2008-01-01

    Full Text Available The aim of this work was to map actual iodine status and its seasonal differences in raw milk of dairy cows, sheep, and goats in various regions of Slovakia. Iodine concentrations were determined in 457 samples of raw milk from dairy cows, 78 samples of sheep, and 16 samples of goat milk collected in various regions of Slovakia from 2002 to 2007. Among all the 457 samples of bovine milk, iodine content below 50 μg l-1 was recorded in 114 samples (24.94%; 294 samples (64.33% ranged between 50 and 200 μg l-1; 19 samples (4.16% from 200 to 500 μg l-1; 17 samples (3.72% between 500 and 1 000 μg l-1, and 13 samples (2.85% showed iodine concentrations over 1 000 μg l-1. regional concentrations showed the highest values in the Western, then Middle and Eastern Slovakia, and the lowest values in Northern Slovakia (p p -1 in 49 sheep (62.8% and in 6 goats below 60 μg l-1 (37.5%, which are indicative of iodine deficiency. When comparing seasonal differences, sheep and goat milk had higher iodine content during the winter feeding period, however, in dairy cows we recorded the opposite ratio. Except for goat milk (p < 0.01 the seasonal differences were not significant.

  20. Iodine excretion in school children in Copenhagen

    DEFF Research Database (Denmark)

    Rasmussen, Lone B; Kirkegaard-Klitbo, Ditte Marie; Laurberg, Peter

    2016-01-01

    objective of this study was to assess iodine excretion in children living in Copenhagen to establish whether a moderate increase in iodine fortification would lead to excess iodine intake in this group. METHODS: Children in first and fifth grade were recruited through schools in Copenhagen. In total, 244......INTRODUCTION: Studies of dietary habits show a high iodine intake in children in Denmark. Iodine excretion in children has not previously been assessed. Iodine excretion in adults is below the recommended threshold, and it is therefore being discussed to increase the fortification level. The main...... according to grade. The UIC was higher in children than in adults from the same area. CONCLUSIONS: The iodine excretion among schoolchildren in Copenhagen, an area with a relatively high iodine content in tap water, was within the recommended range as assessed by the UIC. An increased iodine fortification...

  1. Iodine filters in nuclear power stations

    International Nuclear Information System (INIS)

    Wilhelm, J.G.

    1977-04-01

    On the basis of calculated and recorded release rates of nuclear power plants, the significance of iodine releases in the invironmental impact relative to other nuclides is discussed. The release pathways for iodine in LWR-type reactors and the efficiency of various methods to lower the activity release are given. The airborne species of iodine are discussed with regard to their removal in iodine sorption filters and environmental impact. The technical status of iodine removal by means of iodine sorption filters is studied for normal operation and accident conditions in nuclear power stations on the basis of the data given in the relevant literature for the efficiency of a number of iodine sorption materials. The applicability of concepts for ventilation and containment and their influence on iodine filter systems are discussed. Design, structure, and testing of iodine sorption filters are treated in detail; recommendations for design are given, and failure sources are mentioned. (orig.) [de

  2. Iodine excretion in school children in Copenhagen

    DEFF Research Database (Denmark)

    Rasmussen, Lone B.; Kirkegaard-Klitbo, Ditte Marie; Laurberg, Peter

    2016-01-01

    INTRODUCTION: Studies of dietary habits show a high iodine intake in children in Denmark. Iodine excretion in children has not previously been assessed. Iodine excretion in adults is below the recommended threshold, and it is therefore being discussed to increase the fortification level. The main...... according to grade. The UIC was higher in children than in adults from the same area. CONCLUSIONS: The iodine excretion among schoolchildren in Copenhagen, an area with a relatively high iodine content in tap water, was within the recommended range as assessed by the UIC. An increased iodine fortification...... objective of this study was to assess iodine excretion in children living in Copenhagen to establish whether a moderate increase in iodine fortification would lead to excess iodine intake in this group. METHODS: Children in first and fifth grade were recruited through schools in Copenhagen. In total, 244...

  3. Iodine status in neonates in Denmark

    DEFF Research Database (Denmark)

    Nøhr, S B; Laurberg, Peter; Børlum, K G

    1994-01-01

    Iodine status of 147 neonates born in five different regions of Denmark was evaluated in relation to the iodine content of breast milk and iodine supplementation taken by the mother. Approximately two-thirds of the women had not received iodine supplementation. They had low iodine concentrations...... in breast milk and urinary iodine concentrations of the neonates at day 5 were low. The median values (milk/urine) were 33.6/31.7 micrograms/l (Randers 22/26, Ringkøbing 29/16, Aalborg 36/31. Arhus 54/41 and Copenhagen 55/59 micrograms/l). Higher values were found in the group where tablets containing...... iodine had been taken (milk/urine: 57.0/61.0 micrograms/l). In general, the values are low compared with internationally recommended levels. We suggest that mothers without autoimmune thyroid disease should receive iodine supplementation in the form of vitamin/mineral tablets containing iodine (150...

  4. Organic iodine removal from simulated dissolver off-gas systems utilizing silver-exchanged mordenite

    International Nuclear Information System (INIS)

    Jubin, R.T.

    1981-01-01

    The removal of methyl iodide by adsorption onto silver mordenite was studied using a simulated off-gas from the fuel dissolution step of a nuclear fuel reprocessing plant. The adsorption of methyl iodide on silver mordenite was examined for the effect of NO/sub x/, humidity, iodine concentration, filter temperature, silver loadings and filter pretreatment. The highest iodine loading achieved in these tests was 142 mg CH 3 I per g of substrate on fully exchanged zeolite, approximately the same as elemental iodine loadings. A filter using fully exchanged silver mordenite operating at 200 0 C obtained higher iodine loadings than a similar filter operating at 150 0 C. Pretreatment of the sorbent bed with hydrogen rather than dry air, at a temperature of 200 0 C, also improved the loading. Variations in the methyl iodide concentration had minimal effects on the overall loading. Filters exposed to moist air streams attained higher loadings than those in contact with dry air. Partially exchanged silver mordenite achieved higher silver utilizations than the fully exchanged material. The partially exchanged mordenite also achieved higher loadings at 200 0 C than at 250 0 C. The iodine loaded onto these beds was not stripped at 500 0 C by either 4.5% hydrogen or 100% hydrogen; however, the iodine could be removed by air at 500 0 C, and the bed could be reloaded. A study of the regeneration characteristics of fully exchanged silver mordenite indicates limited adsorbent capacity after complete removal of the iodine with 4.5% hydrogen in the regeneration gas stream at 500 0 C. The loss of adsorbent capacity is much higher for silver mordenite regenerated in a stainless steel filter housing than in a glass filter housing

  5. Control of the amount of free molecular iodine in iodine germicides.

    Science.gov (United States)

    Hickey, J; Panicucci, R; Duan, Y; Dinehart, K; Murphy, J; Kessler, J; Gottardi, W

    1997-12-01

    Horseradish peroxidase has been used to generate iodine compositions that comprised principally free molecular iodine. The concentration of free molecular iodine in these enzyme-based compositions ranged from 44 to 63% of the thiosulphate titratable iodine; this is substantially higher than the corresponding value for the povidone-iodine preparation betadine. The biocidal efficacy of these compositions was proportional to the concentration of free molecular iodine. Iodine compositions with relatively low total iodine concentrations but high levels of free molecular iodine (20-175 ppm) killed Staphylococcus aureus and spores of Bacillus subtilis more rapidly than betadine. The effects of normal saline and these enzyme-based iodine compositions on the rate of epidermal regeneration in superficial swine wounds were comparable. These results suggest that an effective germicide containing a high level of molecular iodine need not be irritating or toxic.

  6. Study of Iodine Prophylaxis Following Nuclear Accidents

    International Nuclear Information System (INIS)

    Sri Widayati; Tedjasari, R. S.; Elfida

    2007-01-01

    Study of iodine prophylaxis following nuclear accidents has been done. Giving stable iodine to a population exposed by I-131 is one of preventive action from internal radiation to the thyroid gland. Stable iodine could be given as Kl tablet in a range of dose of 30 mg/day to 130 mg/day. Improper giving of stable iodine could cause side effect to health, so then some factors should be considered i. e. dose estimation, age, dose of stable iodine to be given, duration of stable iodine prophylaxis and risk of health. (author)

  7. Dissociation of motor maturation.

    Science.gov (United States)

    DiMario, Francis J

    2003-06-01

    We prospectively acquired clinical data regarding the presentation, evaluation, and developmental progress of all patients identified with dissociated motor maturation to define their clinical outcomes. Children (N = 8) referred for evaluation of suspected cerebral palsy because of delayed sitting or walking and identified to have dissociated motor maturation were followed with serial clinical examination. All displayed the characteristic "sitting on air" posture while held in vertical suspension and had otherwise normal developmental assessments. This posture is composed of the hips held in flexion and abduction with the knees extended and feet plantar or dorsiflexed. Three children were initially evaluated at 10 months of age owing to absence of sitting and five other children were evaluated at a mean of 14 months (range 12-19 months) owing to inability to stand. Follow-up evaluations were conducted over a mean of 10.5 months (range 5-34 months). Five children were born prematurely at 34 to 36 weeks gestation. Denver Developmental Screening Test and general and neurologic examinations were normal except to note hypotonia in six children and the "sitting on air" posture in all of the children. Four children have older siblings or parents who "walked late" (after 15 months). On average, the children attained sitting by 8 months (range 7-10 months). One child did not crawl prior to independent walking, two children scooted rather than crawled, and five children crawled at an average of 13.5 months (range 10-16 months). All children cruised by a mean of 18 months (range 16-21.5 months) and attained independent walking by 20.1 months (range 18-25 months). Neuroimaging and serum creatine kinase enzyme testing were normal in two children who were tested. These eight children conform to the syndrome of dissociated motor maturation. The "sitting on air" posture serves as a diagnostic sign and anticipated excellent prognosis, but follow-up is required to ensure a normal

  8. Acidic gases (CO2, NO2 and SO2) capture and dissociation on metal decorated phosphorene

    Science.gov (United States)

    Kuang, Anlong; Kuang, Minquan; Yuan, Hongkuan; Wang, Guangzhao; Chen, Hong; Yang, Xiaolan

    2017-07-01

    Density functional theory is employed to investigate the adsorption and dissociation of several acidic gases (CO2, NO2 and SO2) on metal (Li, Al, Ni and Pt) decorated phosphorene. The results show that light metal (Li, Al) decorated phosphorene exhibits a strong adsorption of acidic gases, i.e., the adsorption energy of CO2 on Li decorated phosphorene is 0.376 eV which is the largest in all adsorption of CO2 on metal decorated phosphorene and Al decorated phosphorene is most effective for capture of NO2 and SO2 due to large adsorption energies of 3.951 and 3.608 eV, respectively. Moreover, Li and Al light metals have stronger economic effectiveness and more friendly environment compared with the transition metals, the strong adsorption ability of acidic gases and low price suggest that Li, Al decorated phosphorene may be useful and promising for collection and filtration of exhaust gases. The reaction energy barriers of acidic gases dissociated process on Pt decorated phosphorene are relatively low and the reaction processes are significantly exothermic, indicating that the dissociation process is favorable.

  9. CO dissociation on magnetic Fen clusters

    KAUST Repository

    Jedidi, Abdesslem

    2014-01-01

    This work theoretically investigates the CO dissociation on Fen nanoparticles, for n in the range of 1-65, focusing on size dependence in the context of the initial step of the Fischer-Tropsch reaction. CO adsorbs molecularly through its C-end on a triangular facet of the nanoparticle. Dissociation becomes easier when the cluster size increases. Then, the C atom is bonded to a square facet that is generated as a result of the adsorption if it does not yet exist in the bare cluster, while the O atom is adsorbed on a triangular facet. In the most stable situation, the two adsorbed atoms remain close together, both having in common one shared first-neighbor iron atom. There is a partial spin quenching of the neighboring Fe atoms, which become more positively charged than the other Fe atoms. The shared surface iron atom resembles a metal-cation from a complex. Despite the small size of the iron cluster considered, fluctuations due to specific configurations do not influence properties for n > 25 and global trends seem significant.

  10. [Dissociative disorders and affective disorders].

    Science.gov (United States)

    Montant, J; Adida, M; Belzeaux, R; Cermolacce, M; Pringuey, D; Da Fonseca, D; Azorin, J-M

    2014-12-01

    The phenomenology of dissociative disorders may be complex and sometimes confusing. We describe here two cases who were initially misdiagnosed. The first case concerned a 61 year-old woman, who was initially diagnosed as an isolated dissociative fugue and was actually suffering from severe major depressive episode. The second case concerned a 55 year-old man, who was suffering from type I bipolar disorder and polyvascular disease, and was initially diagnosed as dissociative fugue in a mooddestabilization context, while it was finally a stroke. Yet dissociative disorders as affective disorder comorbidity are relatively unknown. We made a review on this topic. Dissociative disorders are often studied through psycho-trauma issues. Litterature is rare on affective illness comorbid with dissociative disorders, but highlight the link between bipolar and dissociative disorders. The later comorbidity often refers to an early onset subtype with also comorbid panic and depersonalization-derealization disorder. Besides, unipolar patients suffering from dissociative symptoms have more often cyclothymic affective temperament. Despite the limits of such studies dissociative symptoms-BD association seems to correspond to a clinical reality and further works on this topic may be warranted. Copyright © 2014 L’Encéphale. Published by Elsevier Masson SAS.. All rights reserved.

  11. [Assessment of dietary iodine intake of population in non-high-iodine areas in China].

    Science.gov (United States)

    Song, Xiaoyu; Li, Fengqin; Liu, Zhaoping; He, Yuna; Sui, Haixia; Mao, Weifeng; Liu, Sana; Yan, Weixing; Li, Ning; Chen, Junshi

    2011-03-01

    To assess the potential risk of dietary iodine insufficiency of population in non-high-iodine areas (water iodine China. The dietary iodine intake of 13 age-sex population groups were estimated by combining the data of iodine intake from food, table salt and drinking water. Two conditions were considered: consuming iodized salt or non-iodized salt. The data of food and table salt consumption were derived from the Chinese National Nutrition and Health Survey in 2002. Water consumption was calculated as the recommended water intake. Iodine contents of food, table salt and water were calculated from China Food Composition Table and iodine surveillance data. Under the condition of consuming iodized salt, the average iodine intake of all population groups was higher than the Recommended Nutrient Intake (RNI), while the iodine intakes of individuals above Upper Limits (UL) and below RNI were 5.8% and 13.4% respectively, and the iodine intake of individuals lower than the Estimated Average Requirement (EAR) was 9.4% in adults above 18 years of age (including pregnant and lactating women). If non-iodized salt was consumed, the average iodine intake of most sex-age population groups was higher than RNI, but the iodine intake of 97.6% of individuals would be lower than RNI, while the iodine intake of 97.4% of adults would be lower than EAR. The contribution of iodine from table salt was much higher than that from drinking water and food in the condition of consuming iodized salt, while food was the predominant contributor of dietary iodine in the condition of consuming non-iodized salt. The health risk of iodine deficiency was higher than that of iodine excess in areas where water iodine was China, and the risk of iodine insufficiency was much higher if non-iodized salt was consumed. Iodized salt should be the main sources of dietary iodine intake for population in areas where water iodine was China.

  12. Urinary Iodine Concentrations Indicate Iodine Deficiency in Pregnant Thai Women but Iodine Sufficiency in Their School-Aged Children

    NARCIS (Netherlands)

    Gowachirapant, S.; Winichagoon, P.; Wyss, L.; Tong, B.; Baumgartner, J.; Boonstra, A.; Zimmermann, M.B.

    2009-01-01

    The median urinary iodine concentration (UI) in school-aged children is recommended for assessment of iodine nutrition in populations. If the median UI is adequate in school-aged children, it is usually assumed iodine intakes are also adequate in the remaining population, including pregnant women.

  13. Dissociative State and Competence

    Directory of Open Access Journals (Sweden)

    Yu-Ju Lin

    2007-10-01

    Full Text Available This report presents the results of forensic evaluation of the civil competence of a case of alleged dissociative identity disorder (DID and discusses whether such dissociative states substantially jeopardize civil competence. A 40-year-old woman claimed that she had had many personalities since her college days. From the age of 37 to 40, she shopped excessively, which left her with millions of dollars of debt. She ascribed her shopping to a certain identity state, over which she had no control. (In this article, we use the term identity state to replace personality as an objective description of a mental state. She thus raised the petition of civil incompetence. During the forensic evaluation, it was found that the identity states were relatively stable and mutually aware of each other. The switch into another identity state was sometimes under voluntary control. The subject showed consistency and continuity in behavioral patterns across the different identity states, and no matter which identity state she was in, there was no evidence of impairment in her factual knowledge of social situations and her capacity for managing personal affairs. We hence concluded that she was civilly competent despite the claimed DID. Considering that the existence and diagnosis of DID are still under dispute and a diagnosis of DID alone is not sufficient to interdict a person's civil right, important clinical and forensic issues remain to be answered.

  14. Effect of iodine solutions on polyaniline films

    International Nuclear Information System (INIS)

    Ayad, M.M.; Amer, W.A.; Stejskal, J.

    2009-01-01

    Polyaniline (PANI) emeraldine-base films have been exposed to iodine solutions. The interaction between the films and the iodine solution was studied using the quartz-crystal microbalance (QCM) technique and the UV-visible absorption spectroscopy. The iodine-treated film of emeraldine base was subjected to dedoping process using 0.1 M ammonia solution. The resulting film was exposed again to the previously used iodine solution. Iodine was found to play multiple roles: the ring-iodination of PANI film, the oxidation of PANI to pernigraniline base, and iodine doping to PANI salt. A sensor based on PANI-coated electrode of QCM was developed to monitor the presence of iodine in solution.

  15. Iodinated contrast media nephrotoxicity

    International Nuclear Information System (INIS)

    Meyrier, A.

    1994-01-01

    In the late seventies, iodinated contrast agents (ICA) were considered to be a major cause of acute iatrogenic renal failure. Over the last decade new contrast agents have been synthesized, nonionic and less hyperosmolar. The incidence of acute renal failure due to ICAs, varies from 3.7 to 70% of cases according to the series, with an average figure of 10.2%. The pathophysiology of ICA nephrotoxicity was mainly studied in laboratory animal models. Three main factors are involved in an inducing ICA-mediated decrease in glomerular filtration rate: reduction of the renal plasma flow, a direct cytotoxic effect on renal tubular cells and erythrocyte alteration leading to intra-renal sludge. Excluding dysglobulinemias with urinary excretion of immunoglobulin light chains, which represent a special case of maximum nephrotoxicity, 4 main risk factors of renal toxicity have been identified in nondiabetic subjects: previous renal failure with serum creatinine levels greater than 140 μmol per liter, extracellular dehydration, age over 60 and use of high doses of ICA and/or repeated ICA injections before serum creatinine levels return to baseline. Preventive measures for avoiding ICA nephrotoxicity are threefold: maintain or restore adequate hydration with saline infusion, stop NSAID treatment several days before ICA administration, and allow a 5 day interval before repeating contrast media injections. New, nonionic and moderately hyperosmolar contrast agents appear to be much less nephrotoxic than conventional ICAs in laboratory animals and in high-risk patients. It is advisable to select such contrast media for investigating high-risk patients. This approach was recently substantiated in well designed, randomized clinical studies which included more than 2 000 patients. (author)

  16. Hyperglycemia associated dissociative fugue (organic dissociative disorder) in an elderly.

    Science.gov (United States)

    Ram, Dushad; Ashoka, H G; Gowdappa, Basavnna

    2015-01-01

    Inadequate glycemic control in patients with diabetes is known to be associated with psychiatric disorders such as depression, anxiety disorder, and cognitive impairment. However, dissociative syndrome has not been reported so far. Here we are reporting a case of repeated dissociative fugue associated with hyperglycemia, in an elderly with type II diabetes. Possible neurobiological mechanism has been discussed.

  17. Hyperglycemia associated dissociative fugue (organic dissociative disorder) in an elderly

    OpenAIRE

    Ram, Dushad; Ashoka, H. G; Gowdappa, Basavnna

    2015-01-01

    Inadequate glycemic control in patients with diabetes is known to be associated with psychiatric disorders such as depression, anxiety disorder, and cognitive impairment. However, dissociative syndrome has not been reported so far. Here we are reporting a case of repeated dissociative fugue associated with hyperglycemia, in an elderly with type II diabetes. Possible neurobiological mechanism has been discussed.

  18. Hyperglycemia associated dissociative fugue (organic dissociative disorder in an elderly

    Directory of Open Access Journals (Sweden)

    Dushad Ram

    2015-01-01

    Full Text Available Inadequate glycemic control in patients with diabetes is known to be associated with psychiatric disorders such as depression, anxiety disorder, and cognitive impairment. However, dissociative syndrome has not been reported so far. Here we are reporting a case of repeated dissociative fugue associated with hyperglycemia, in an elderly with type II diabetes. Possible neurobiological mechanism has been discussed.

  19. Formation and behaviour of organic iodine

    International Nuclear Information System (INIS)

    Zilliacus, R.; Koukkar, P.; Karjunen, T.; Sjoevall, H.

    2002-01-01

    The report presents experimental studies on the formation of organic iodine in severe reactor accidents. The analyses were performed to evaluate the amount of alkaline chemical needed for effective pH control of containment water during the accidents. The formation of organic iodine in solutions used in the filtered venting system and the absorption of iodine compounds in the solutions were studied. Experiments for the formation of organic iodine on painted surfaces were also performed. (au)

  20. Mineral resource of the month: iodine

    Science.gov (United States)

    Polyak, Désirée E.

    2009-01-01

    The article focuses on iodine, its benefits and adverse effects, and its production and consumption. It states that iodine is essential to humans for it produces thyroid hormones to nourish thyroid glands but excessive intake could cause goiter, hyperthyroidism or hypothyroidism. U.S. laws require salt iodization to help prevent diseases. Chile and Japan are the world's leading iodine producer while in the U.S. iodine is mined from deep well brines in northern Oklahoma.

  1. Contrast induced hyperthyroidism due to iodine excess

    OpenAIRE

    Mushtaq, Usman; Price, Timothy; Laddipeerla, Narsing; Townsend, Amanda; Broadbridge, Vy

    2009-01-01

    Iodine induced hyperthyroidism is a thyrotoxic condition caused by exposure to excessive iodine. Historically this type of hyperthyroidism has been described in areas of iodine deficiency. With advances in medicine, iodine induced hyperthyroidism has been observed following the use of drugs containing iodine—for example, amiodarone, and contrast agents used in radiological imaging. In elderly patients it is frequently difficult to diagnose and control contrast related hyperthyroidism, as most...

  2. Laser Induced Fluorescence of the Iodine Ion

    Science.gov (United States)

    2014-09-01

    density of iodine (solid at room temperature) is 4.933 g/cc. Iodine also has a relatively high vapor pressure at low temperatures. Vapor pressures of...unknowns with iodine – Vapor pressure requires temperature control – New flow control system design/complexity – Performance and lifetime? – Safety... Iodine is a demonstrated HET propellant – Cheaper than xenon, similar critical properties – 3x higher storage density – Low pressure storage • Issues

  3. Iodine content in bread and salt in Denmark after iodization and the influence on iodine intake

    DEFF Research Database (Denmark)

    Rasmussen, Lone Banke; Ovesen, Lars; Christensen, Tue

    2007-01-01

    Objective To measure the iodine content in bread and household salt in Denmark after mandatory iodine fortification was introduced and to estimate the increase in iodine intake due to the fortification. Design The iodine content in rye breads, wheat breads and salt samples was assessed....... The increase in iodine intake from fortification of bread and the increase in total iodine intake after fortification were estimated. Subjects Iodine intake before and after fortification was estimated based on dietary intake data from 4,124 randomly selected Danish subjects. Main results Approximately 98......% of the rye breads and 90% of the wheat breads were iodized. The median iodine intake from bread increased by 25 ( 13-43) mu g/day and the total median iodine intake increased by 63 (36-104) mu g/day. Conclusions The fortification of bread and salt has resulted in a desirable increase in iodine intake...

  4. Competitive Protein Adsorption of Albumin and Immunoglobulin G from Human Serum onto Polymer Surfaces

    DEFF Research Database (Denmark)

    Holmberg, Maria; Hou, Xiaolin

    2010-01-01

    Competitive protein adsorption from human serum onto unmodified polyethylene terephthalate (PET) surfaces and plasma-polymerized PET surfaces, using the monomer diethylene glycol vinyl ether (DEGVE), has been investigated using radioactive labeling. Albumin and immunoglobulin G (IgG) labeled...... with two different iodine isotopes have been added to human serum solutions of different concentrations, and adsorption has been performed using adsorption times from approximately 5 s to 24 h. DEGVE surfaces showed indications of being nonfouling regarding albumin and IgG adsorption during competitive...... protein adsorption from diluted human serum solutions with relatively low protein concentrations, but the nonfouling character was weakened when less diluted human serum solutions with higher protein concentrations were used. The observed adsorption trend is independent of adsorption time, indicating...

  5. Management modes for iodine-129

    International Nuclear Information System (INIS)

    White, I.F.; Smith, G.M.

    1984-01-01

    This study completes a two-stage programme, supported by the Commission of the European Communities, on management modes for iodine-129. The models for the radiological assessment of iodine-129 management modes have been reviewed and, where necessary, revised, and a generic radiological assessment has been carried out using these models. Cost benefit analysis has been demonstrated for a variety of iodine-129 management modes; for a wide range of assumptions, the costs of abatement of atmospheric discharges would be outweighed by the radiological benefits. The cost benefit analysis thus complements and confirms the preliminary conclusion of the previous study: iodine-129 should be trapped to a large extent from the off-gases of a large reprocessing plant and disposed of by other suitable means, in order to ensure that all exposures from this radionuclide are as low as reasonably achievable. Once the major fraction of the iodine-129 throughput of a reprocessing plant has been trapped from the dissolver off-gases, there are unlikely to be strong radiation protection incentives either for further trapping from the dissolver off-gases or for trapping from the vessel off-gases. In a generic study it is not possible to state an optimum choice of process(es) for abatement of atmospheric discharges of iodine-129. This choice must be determined by assessments in the specific context of a particular reprocessing plant, its site, the waste disposal routes that are actually available, and also in the wider context of the management plans for all radioactive wastes at the plant in question

  6. Computational study of ethanol adsorption and reaction over rutile TiO2 (110) surfaces

    KAUST Repository

    Muir, J. N.

    2012-01-01

    Studies of the modes of adsorption and the associated changes in electronic structures of renewable organic compounds are needed in order to understand the fundamentals behind surface reactions of catalysts for future energies. Using planewave density functional theory (DFT) calculations, the adsorption of ethanol on perfect and O-defected TiO 2 rutile (110) surfaces was examined. On both surfaces the dissociative adsorption mode on five-fold coordinated Ti cations (Ti 4+ 5c) was found to be more favourable than the molecular adsorption mode. On the stoichiometric surface E ads was found to be equal to 0.85 eV for the ethoxide mode and equal to 0.76 eV for the molecular mode. These energies slightly increased when adsorption occurred on the Ti 4+ 5c closest to the O-defected site. However, both considerably increased when adsorption occurred at the removed bridging surface O; interacting with Ti 3+ cations. In this case the dissociative adsorption becomes strongly favoured (E ads = 1.28 eV for molecular adsorption and 2.27 eV for dissociative adsorption). Geometry and electronic structures of adsorbed ethanol were analysed in detail on the stoichiometric surface. Ethanol does not undergo major changes in its structure upon adsorption with its C-O bond rotating nearly freely on the surface. Bonding to surface Ti atoms is a σ type transfer from the O2p of the ethanol-ethoxide species. Both ethanol and ethoxide present potential hole traps on O lone pairs. Charge density and work function analyses also suggest charge transfer from the adsorbate to the surface, in which the dissociative adsorptions show a larger charge transfer than the molecular adsorption mode. This journal is © 2012 the Owner Societies.

  7. Computational study of ethanol adsorption and reaction over rutile TiO2 (110) surfaces.

    Science.gov (United States)

    Muir, J M R; Muir, J N; Choi, Y; Idriss, H

    2012-09-14

    Studies of the modes of adsorption and the associated changes in electronic structures of renewable organic compounds are needed in order to understand the fundamentals behind surface reactions of catalysts for future energies. Using planewave density functional theory (DFT) calculations, the adsorption of ethanol on perfect and O-defected TiO(2) rutile (110) surfaces was examined. On both surfaces the dissociative adsorption mode on five-fold coordinated Ti cations (Ti(4+)(5c)) was found to be more favourable than the molecular adsorption mode. On the stoichiometric surface E(ads) was found to be equal to 0.85 eV for the ethoxide mode and equal to 0.76 eV for the molecular mode. These energies slightly increased when adsorption occurred on the Ti(4+)(5c) closest to the O-defected site. However, both considerably increased when adsorption occurred at the removed bridging surface O; interacting with Ti(3+) cations. In this case the dissociative adsorption becomes strongly favoured (E(ads) = 1.28 eV for molecular adsorption and 2.27 eV for dissociative adsorption). Geometry and electronic structures of adsorbed ethanol were analysed in detail on the stoichiometric surface. Ethanol does not undergo major changes in its structure upon adsorption with its C-O bond rotating nearly freely on the surface. Bonding to surface Ti atoms is a σ type transfer from the O2p of the ethanol-ethoxide species. Both ethanol and ethoxide present potential hole traps on O lone pairs. Charge density and work function analyses also suggest charge transfer from the adsorbate to the surface, in which the dissociative adsorptions show a larger charge transfer than the molecular adsorption mode.

  8. SHORT COMMUNICATION EFFICIENT AND DIRECT IODINATION ...

    African Journals Online (AJOL)

    Preferred Customer

    KEY WORDS: Iodine, Polymer-supported periodic acid, Oxidant, Iodination. INTRODUCTION. Iodobenzene derivatives are valuable compounds in organic synthesis, medicine, and biochemistry [1]. Iodine is an elemental halogen that has less reactive than the other halides in electrophilic substitution reactions, therefore ...

  9. Iodine in Enteral and Parenteral Nutrition

    NARCIS (Netherlands)

    Zimmermann, M.B.; Crill, C.M.

    2010-01-01

    Iodine deficiency (ID) has multiple adverse effects on growth and development due to inadequate thyroid hormone production. Methods for assessment of iodine nutrition in individuals include the urinary iodine concentration (UI), thyroid size and thyroid function tests. The UI measured in several

  10. Industrial system for producing iodine-123

    International Nuclear Information System (INIS)

    Brantley, J.C.

    1985-01-01

    An industrial system to produce iodine-123 required a complex set of steps involving new approaches by the Food and Drug Administration, difficult distribution procedures, and evidence from potential users that either very pure iodine-123 or inexpensive iodine-123 is needed. Industry has shown its willingness to invest in new radionuclides but needs strong evidence as to product potential to justify those investments

  11. Infrared spectroscopic study of radiation-induced adsorption of n-hexane on a beryllium surface

    Science.gov (United States)

    Gadzhieva, N. N.

    2017-07-01

    Radiation-stimulated adsorption on a beryllium surface is studied by IR reflection-absorption spectroscopy. It is found that γ-irradiation at room temperature leads to the appearance of n-hexane adsorption centers on a beryllium surface according to molecular and dissociation mechanisms. The kinetics of n-hexane adsorption in a Be- n-hexane system is studied; activated dissociative chemisorption accompanied by formation of beryllium alkyls and surface hydrides is observed at absorbed doses 15 kGy ≤ Vγ ≤ 35 kGy. A possible mechanism of this process is suggested.

  12. Iodine losses during Winkler titrations

    Science.gov (United States)

    Knapp, George P.; Stalcup, Marvel C.; Stanley, Robert J.

    1991-01-01

    An experiment designed to measure iodine loss during the aliquot version of the Winkler titration for dissolved oxygen in seawater shows that 0.01-0.03 ml l -1 equivalent oxygen is lost at typical oceanic concentrations in the method presently used. A standardization technique, which mimics that employed during the titration of seawater samples, compensates for this iodine loss throughout the oceanic range. This result, contradicting an earlier report by GREEN and CARRITT (1966, Analyst, 91, 207-208), demonstrates that the whole-bottle method of oxygen titration is not to be preferred over the aliquot method.

  13. Trauma and dissociation: treatment perspectives.

    Science.gov (United States)

    Kreidler, M C; Zupancic, M K; Bell, C; Longo, M B

    2000-01-01

    How advanced practice nurses can work with trauma survivors to decrease dissociation as a needed coping mechanism. To review the literature on trauma and dissociation as well as current treatment perspectives. Review of the literature and authors' clinical experience. Advanced practice nurses can use knowledge of selected psychopharmacological medications and Erikson's stages of psychosocial development to plan treatment for posttrauma clients.

  14. Dissociation: a developmental psychoneurobiological perspective ...

    African Journals Online (AJOL)

    Dissociation is a common symptom of a spectrum of severe psychopathologies, from reactive attachment disorder of infants to dissociative identity disorders, psychotic experiences, borderline personality disorders and post-traumatic stress disorders of adults. The incidence of abuse in the childhood histories of adults with ...

  15. AV dissociation, an inevitable response.

    Science.gov (United States)

    Wang, Kyuhyun; Benditt, David G

    2011-07-01

    The independent activation of the atria and ventricles, AV dissociation, is a common phenomenon that occurs during a wide variety of electrophysiologic circumstances. The clinical significance of AV dissociation is often misunderstood. This article examines the basis and clinical implications of AV dissociation. AV dissociation is often an obligatory, secondary phenomenon, and should not be construed as the primary disorder; it may be due to either the AV conduction system being completely blocked (3° AV block) or the P wave and the QRS complex being generated from separate sources (usually, the AV junction or ventricle) but occurring close together during the physiologic refractory period of each other. The latter may happen in junctional or ventricular arrhythmias including escape or accelerated rhythm, tachycardia, or premature beats. The crucial clinical point is not the AV dissociation itself, but that an underlying triggering primary disorder is present and should be identified. ©2011, Wiley Periodicals, Inc.

  16. First application of an online method for quantification of maritime molecular iodine and hypoiodic acid in maritime aerosol during PEGASO cruise

    Science.gov (United States)

    Götz, Sven; Dall'Osto, Manuel; Simó, Rafel; Hoffmann, Thosten

    2015-04-01

    The atmospheric chemistry of iodine is important in multiple ways. The focus lies on the ability to influence the oxidizing capacity of the atmosphere, i.e. by destruction of ozone, and the formation of iodine oxide particles (IOP), i.e. the influence on condensation nuclei (CCN). Using a variation of techniques, like differential optical absorption spectroscopy (DOAS), laser-induced fluorescence (LIF), inductively coupled plasma mass spectrometry (ICP-MS) and atmospheric pressure chemical ionization with tandem mass spectrometry (APCI-MS/MS), the reactive iodine species of atomic iodine (I), molecular iodine (I2), iodine monoxide (IO) and iodine dioxide (OIO) have all been detected in the atmosphere from Antarctica to the equatorial marine boundary layer (MBL). In the past few years there have been active research on IO, especially after revealing significant levels in open ocean measurements, and higher iodine oxides. In addition to atmospheric measurements, significant developments in laboratory kinetics, photochemistry and heterogeneous chemistry of iodine species have been accomplished. [1] Here we introduce the first field application of an online-method for detecting gaseous molecular iodine and HOI, which is a further development of a technique [2] based on selective photolytic dissociation, followed by oxidization and particle formation of iodine compounds. The particles are than size-segregated and detected by a scanning mobility particle sizer (SMPS) system. Initial IOP forming is performed in a reaction chamber providing specific wavelengths according to corresponding bond dissociation thresholds. Additionally offline sampling of iodine and iodine containing interhalogenes with coated diffusion denuders [3] were carried out throughout the cruise to compare both methods after analysis with GC/MS. Furthermore filter samples were taken to perform non-target analysis of organic compounds by UHPLC/ESI(+/-)-HR-MS. Preliminary results of iodine related

  17. Dissociation - a preliminary contextual model

    Directory of Open Access Journals (Sweden)

    C Krüger

    2007-02-01

    Full Text Available Background. The Diagnostic and Statistical Manual of Mental Disorders (DSM system has certain limitations when applied to two South African examples of dissociation, because it is descriptive (non-explanatory and focuses on intrapsychic (non-communal processes. Even the existing Western explanatory models of dissociation fail to accommodate fully the communal aspects of dissociation in our South African context. Objectives and methods. The aim was to explore an expanded perspective on dissociation that does not limit it to an intrapsychic phenomenon, but that accounts for the interrelatedness of individuals within their social context. Auto-ethnography was used. In this article a collective, socially orientated, contextual hermeneutic was applied to two local examples of dissociation. Three existing Western models were expanded along multicontextual, collective lines, for them to be more useful in the pluralistic South African context. Results. This preliminary contextual model of dissociation includes a person’s interpersonal, socio-cultural, and spiritual contexts, in addition to the intrapsychic context. Dissociation is considered to be a normal information-processing tool that maintains balanced, coherent selves-in-society, i.e. individuals connected to each other. In the South African context dissociation appears mostly as a normal phenomenon and seldom as a sign of mental illness. Dissociation is pivotal for the normal construction of individual and communal identities in the face of conflicting sets of information from various contexts. Dissociation may help individuals or communities to survive in a world of conflicting messages, where conflict is often interpersonal/cultural/societal in nature, rather than primarily intrapsychic. Conclusions. This model should be developed and evaluated further. Such evaluation would require suitable new local terminology.

  18. Optimization and scaling of a pulser-sustainer discharge excited oxygen-iodine laser

    Science.gov (United States)

    Bruzzese, J.; Nishihara, M.; Hicks, A.; Lempert, W. R.; Rich, J. W.; Adamovich, I. V.

    2008-05-01

    The paper discusses optimization of gain and output power and scaling of a pulser-sustainer discharge excited oxygen-iodine laser. For this, NO addition to the laser mixture and iodine vapor dissociation in an auxiliary high-voltage, nanosecond pulse duration, repetitively pulsed discharge ("side" discharge) are used. Iodine dissociation fraction generated in the side discharge and measured in the M=3 laser cavity is up to 50%. The experiments showed that additional iodine dissociation generated in the side discharge only moderately increased laser gain, by 10-15%. Parametric gain optimization by varying main discharge pressure, O2 and NO fractions in the flow, I2 flow rate, pulsed discharge frequency, and sustainer discharge power, with the side discharge in operation produced gain up to 0.08 %/cm. Two parameters that critically affect gain are the energy loading per molecule in the discharge and the NO flow rate controlling the O atom concentration in the flow. Operation at the main discharge pressure of 60 torr resulted in significantly higher gain than at 100 torr, 0.080 %/cm vs. 0.043 %/cm, due to high discharge energy loading per molecule at the lower pressure. Laser output power measured at the gain optimized conditions is 1.4 W. Experiments with a scaled-up laser with a large volume pulser-sustainer discharge (10 cm x 10 cm x 2 cm vs. 5 cm x 5 cm x 2 cm) and longer gain path (10 cm vs. 5 cm) demonstrated stable discharge operation at discharge powers up to at least 2.9 kW. Singlet delta yield and gain measurements in the scaled-up laser are underway.

  19. Nighttime atmospheric chemistry of iodine

    Science.gov (United States)

    Saiz-Lopez, Alfonso; Plane, John M. C.; Cuevas, Carlos A.; Mahajan, Anoop S.; Lamarque, Jean-François; Kinnison, Douglas E.

    2017-04-01

    Little attention has so far been paid to the nighttime atmospheric chemistry of iodine species. Atmospheric models predict a buildup of HOI and I2 during the night that leads to a spike of IO at sunrise, which is not observed by measurements. In this work, electronic structure calculations are used to survey possible reactions that HOI and I2 could undergo at night in the lower troposphere, and hence reduce their nighttime accumulation. The new reaction NO3 + HOI → IO + HNO3 is proposed and included in two atmospheric models, along with the known reaction between I2 and NO3, to explore a new nocturnal iodine radical activation mechanism. Our results show that this iodine scheme leads to a considerable reduction of nighttime HOI and I2, which results in the enhancement of more than 25% of nighttime ocean emissions of HOI + I2 and the removal of the anomalous spike of IO at sunrise. That active nighttime iodine could also have a considerable, so far unrecognized, impact on the reduction of the NO3 radical levels in the marine boundary layer (MBL) and hence upon the nocturnal oxidizing capacity of the marine atmosphere. The effect of this is exemplified by the indirect effect on dimethyl sulfide (DMS) oxidation.

  20. Dietary flavonoids and iodine Metabolism

    NARCIS (Netherlands)

    Elst, van der J.P.; Smit, J.W.A.; Romijn, H.A.; Heide, van der D.

    2003-01-01

    Flavonoids have inhibiting effects on the proliferation of cancer cells, including thyroidal ones. In the treatment of thyroid cancer the uptake of iodide is essential. Flavonoids are known to interfere with iodide organification ill vitro, and to cause goiter. The influence of flavonoids on iodine

  1. Method of fixing radioactive iodine

    International Nuclear Information System (INIS)

    Tanuma, Hiroyuki; Yamazaki, Nakamichi; Kubota, Yu; Hoshino, Yoshihiro.

    1986-01-01

    Purpose: To solidify radioactive iodine by adsorbing radioactive iodine to silicate type adsorbents carrying silver thereon, mixing the adsorbents with hydroxides of alkali or alkaline earth metals and subjecting them to hydrothermic reaction. Method: The adsorbents used in this invention are, for example, those silicate type adsorbents carrying silver such as silver-supporting zeolite and silver-supporting moldenite, and the silver supporting amount is suitably from about 30 to 40 % by weight. When radioactive iodine is brought into contact with the adsorbents, it is adsorbed and a portion thereof is present in the instable coupling. Then, at least one of sodium hydroxide, potassium hydroxide and barium hydroxide is mixed in an amount of 1 to 30 % by weight to the adsorbents and maintained under the state of a pressure of higher than 70 kg/cm 2 and a temperature above 150 deg C under the presence of water to conduct hydrothermic reduction, whereby iodine is converted into stable AgI or AgIO 3 and the adsorabents are formed into solidification products. (Takahashi, M.)

  2. Iodine tablets and a nuclear accident

    International Nuclear Information System (INIS)

    Paile, W.

    1992-01-01

    Radioactive iodine is one of the major substances released during severe nuclear accidents. Radioactive iodine is easily gasified, and if present in fallout it can enter the lungs, and thereby the circulatory system, with the inhalation of air. Once in a body, radioactive iodine accumulates in the thyroid and may result in tumours in the thyroid and, in extreme cases, impaired thyroid function. Accumulation of radioactive iodine can be prevented by taking non-radioactive, 'cold' iodine as tablets. Iodine tablets dilute the radioactive iodine that has entered the body. A dose of iodine also paralyses the thyroid temporarily by saturating its iodine-carrying capacity. To be useful iodine tablets should be taken immediately when a radioactive emission has occurred. If the tablets are taken too early or too late, they give little protection. Iodine tablets should not be taken just to be on the safe side, since their use may involve harmful side effects. Dosing instructions should also be followed with care. (orig.)

  3. Electron stimulated desorption study of oxygen adsorption on tungsten

    International Nuclear Information System (INIS)

    Prince, R.H.; Floyd, G.R.

    1978-01-01

    The adsorption of oxygen on a polycrystalline tungsten surface at approximately 800 K has been studied by means of electron stimulated desorption (ESD). Although precision gas dosing was not employed, the initial sticking probability for dissociative adsorption appears to be essentially unity, while the variation with coverage suggests that a high degree of order exists and that precursor state kinetics are significant. A most noticeable and reproducible discontinuity in ESD parameters occurs at a fractional coverage theta approximately 0.8 (exposure approximately 1.4 X 10 15 molecules/cm 2 incident) which is interpreted as an order-disorder transition within a single (β 1 ) chemisorption state, and results in an increase in the ionic desorption cross-section by a factor of approximately 1.26. A discussion of the adsorption kinetics and the disorder transition is given in terms of current models of dissociative adsoption which include the effects of nearest neighbour lateral interactions. (Auth.)

  4. Iodine removing method in organic solvent

    International Nuclear Information System (INIS)

    Suzuki, Takeo; Sakurai, Manabu

    1988-01-01

    Purpose: To effectively remove iodine in an organic solvent to thereby remove iodine in the solvent that can be re-used or put to purning treatment. Method: Organic solvent formed from wastes of nuclear facilities is mixed with basic lead acetate, or silica gel or activated carbon incorporated with such a compound to adsorb iodine in the organic solvent to the basic lead acetate. Then, iodine in the organic solvent is removed by separating to eliminate the basic lead acetate adsorbing iodine from the organic solvent or by passing the organic solvent through a tower or column charged or pre-coated with silica gel or activated carbon incorporated with lead acetate. By using basic lead acetate as the adsorbents, iodine can effective by adsorbed and eliminated. Thus, the possibility of circumstantial release of iodine can be reduced upon reusing or burning treatment of the organic solvent. (Kamimura, M.)

  5. Waved graphene: Unique structure for the adsorption of small molecules

    International Nuclear Information System (INIS)

    Pan, Hui

    2017-01-01

    We propose waved graphenes for the strong adsorption of molecules and investigate their potential applications. We find that the physical adsorption of molecules on waved graphene is greatly enhanced by compression. At optimal compression, the physical adsorption energies of H 2 , N 2 , NO, and CO are increased by 6–9 times, and that for O 2 is more than 2 times. We show that the energy for their chemical adsorption on waved graphene decreases dramatically with the increment of compression. The energy of dissociation of H 2 on flat graphene is 1.63 eV and reduced to 0.06 eV (96% reduction) on waved graphene at a compression of 50%, respectively. The energy for chemical adsorption of O 2 on waved graphenes is extremely reduced from 0.98 eV to −0.57 eV as with compression increasing from 0 to 50%, indicating the transition of endothermic chemical adsorption to exothermic. We further show that the electronic properties of waved graphenes are modified, leading to the change of electrical characters. We see that the waved graphenes may find applications in gas storage, sensor and catalyst because of enhanced physical and chemical adsorption and the induced change of electronic properties. - Highlights: • Adsorption of small molecules on waved graphene is greatly enhanced. • Strong physical adsorption in the trough of waved graphene can be achieved by tuning the curvature. • Chemical adsorption is on the crest of waved graphene. • Exothermic dissociation of H2 and O2 can be realized on waved graphene under high compression. • Wave graphene can be candidates as catalysts and gas storage/sensor.

  6. Iodine deficiency in pregnancy in Denmark. Regional variations and frequency of individual iodine supplementation

    DEFF Research Database (Denmark)

    Nøhr, S B; Laurberg, Peter; Børlum, K G

    1993-01-01

    Iodine requirements are increased during pregnancy and lactation and adequate iodine intake is important for normal brain development of the fetus/newborn child. The aim of the present study was to evaluate the extent to which this increase in iodine requirement is met in pregnant women living...... in various regions of Denmark. One hundred and fifty-two healthy pregnant women admitted to five different Danish departments of obstetrics participated in the study. Iodine status was evaluated by measurement of iodine in spot urine at day five after delivery and by careful history of the intake of iodine...... containing vitamin/mineral tablets. Approximately one third of the women had received tablets containing iodine. In women who had not received iodine supplementation urinary iodine was low with a median value of 39.7 micrograms/g creatinine (Aalborg 28, Randers 33, Ringkøbing 34, Arhus 43 and Copenhagen 62...

  7. Determination of iodine and iodine compounds in marine samples by ICPMS and HPLC-ICPMS

    DEFF Research Database (Denmark)

    Hansen, Maiken Sødergreen; Lewandowski, Daniel Jacob; Rasmussen, Rie Romme

    2014-01-01

    By now it is a well-known fact that iodine is an essential trace element for the growth and development of the human body. Because of iodine deficiency, some countries have added iodate to salt in order to increase the iodine intake. However, some people prefer iodine from more natural sources like...... seaweed and fish, which contain elevated levels of iodine (fish typically 1-10 mg/kg and seaweed up to 8000 mg/kg). These marine food items may contain different iodine species, which may have different bioavailability and toxicity, and hence there is an increased interest in developing analytical methods...... for determining the different iodine species. For determining the total iodine concentration in marine samples five different extraction methods were compared. The most efficient and precise method was then used for determining the total concentration of iodine in seaweed and fish samples using inductively...

  8. Iodine status in neonates in Denmark: regional variations and dependency on maternal iodine supplementation

    DEFF Research Database (Denmark)

    Nøhr, S B; Laurberg, P; Børlum, K G

    1994-01-01

    Iodine status of 147 neonates born in five different regions of Denmark was evaluated in relation to the iodine content of breast milk and iodine supplementation taken by the mother. Approximately two-thirds of the women had not received iodine supplementation. They had low iodine concentrations...... in breast milk and urinary iodine concentrations of the neonates at day 5 were low. The median values (milk/urine) were 33.6/31.7 micrograms/l (Randers 22/26, Ringkøbing 29/16, Aalborg 36/31. Arhus 54/41 and Copenhagen 55/59 micrograms/l). Higher values were found in the group where tablets containing...... iodine had been taken (milk/urine: 57.0/61.0 micrograms/l). In general, the values are low compared with internationally recommended levels. We suggest that mothers without autoimmune thyroid disease should receive iodine supplementation in the form of vitamin/mineral tablets containing iodine (150...

  9. Catalytic water dissociation by greigite Fe3S4 surfaces: density functional theory study

    Science.gov (United States)

    Roldan, A.; de Leeuw, N. H.

    2016-01-01

    The iron sulfide mineral greigite, Fe3S4, has shown promising capability as a hydrogenating catalyst, in particular in the reduction of carbon dioxide to produce small organic molecules under mild conditions. We employed density functional theory calculations to investigate the {001},{011} and {111} surfaces of this iron thiospinel material, as well as the production of hydrogen ad-atoms from the dissociation of water molecules on the surfaces. We systematically analysed the adsorption geometries and the electronic structure of both bare and hydroxylated surfaces. The sulfide surfaces presented a higher flexibility than the isomorphic oxide magnetite, Fe3O4, allowing perpendicular movement of the cations above or below the top atomic sulfur layer. We considered both molecular and dissociative water adsorption processes, and have shown that molecular adsorption is the predominant state on these surfaces from both a thermodynamic and kinetic point of view. We considered a second molecule of water which stabilizes the system mainly by H-bonds, although the dissociation process remains thermodynamically unfavourable. We noted, however, synergistic adsorption effects on the Fe3S4{001} owing to the presence of hydroxyl groups. We concluded that, in contrast to Fe3O4, molecular adsorption of water is clearly preferred on greigite surfaces. PMID:27274698

  10. Development of silver impregnated alumina for iodine separation from off-gas streams

    Energy Technology Data Exchange (ETDEWEB)

    Funabashi, Kiyomi; Fukasawa, Tetsuo; Kikuchi, Makoto [Energy Research Laboratory, Hitachi (Japan)] [and others

    1995-02-01

    An inorganic iodine adsorbent, silver impregnated alumina (AgA), has been developed to separate iodine effectively from off-gas streams of nuclear facilities and to decrease the volume of waste (spent adsorbent). Iodine removal efficiency was improved at relatively high humidity by using alumina carrier with two different pore diameters. Waste volume reduction was achieved by impregnating relatively large amounts of silver into the alumina pores. The developed adsorbent was tested first with simulated off-gas streams under various experimental conditions and finally with actual off-gas streams of the Karlsruhe reprocessing plant. The decontamination factor (DF) was about 100 with the AgA bed depth of 2cm at 70% relative humidity, which was a DF one order higher than that when AgA with one pore size was used. Iodine adsorption capacity was checked by passing excess iodine into the AgA bed. Values were about 0.12 and 0.35 g-I/cm`-AgA bed for 10 and 24wt% silver impregnated AgA, respectively. The results obtained in this study demonstrated the applicability of the developed AgA to the off-gas treatment system of nuclear facilities.

  11. The treatment of iodine and chlorine chemistry in the risk assessment of deep radioactive waste disposal

    International Nuclear Information System (INIS)

    Jones, Michael A.

    1992-01-01

    The predicted contribution from 129 I, 131 I and 36 Cl to the radiological risk from a radioactive waste repository may be enhanced by the assumption of limited retardation in the near field and geosphere. However, migration of these radionuclides may be affected by their chemical speciation and retarded by a range of sorption processes. The chemical behaviour of iodine and chlorine is determined emphasizing i) aqueous speciations, ii) sorption onto inorganic substrates, and iii) the role of organic matter and microbes. Recommendations to enhance the methodology include i) consideration of aqueous speciation of iodine, both metal and organic complexes, ii) mechanistic simulation of iodine sorption by ion exchange and electrostatic/covalent adsorption, iii) simulation of enzymatically enhanced sorption of iodine and chlorine onto organic substrates, iv) enhancement of HMIP K d databases to include iodine and chlorine data for the geosphere and biosphere. A well defined programme of additional data collection, modelling studies and experimental investigations is recommended to achieve these enhancements. (author)

  12. Dissociative symptomatology in cancer patients

    Science.gov (United States)

    Civilotti, Cristina; Castelli, Lorys; Binaschi, Luca; Cussino, Martina; Tesio, Valentina; Di Fini, Giulia; Veglia, Fabio; Torta, Riccardo

    2015-01-01

    Introduction: The utilization of the post-traumatic stress disorder (PTSD) diagnostic spectrum is currently being debated to categorize psychological adjustment in cancer patients. The aims of this study were to: (1) evaluate the presence of cancer-related traumatic dissociative symptomatology in a sample of cancer patients; (2) examine the correlation of cancer-related dissociation and sociodemographic and medical variables, anxiety, depression, and post-traumatic stress symptomatology; (3) investigate the predictors of cancer-related dissociation. Methods: Ninety-two mixed cancer patients (mean age: 58.94, ds = 10.13) recruited from two hospitals in northern Italy were administered a questionnaire on sociodemographic and medical characteristics, the Karnofsky Scale to measure the level of patient activity and medical care requirements, the Hospital Anxiety and Depression Scale (HADS) to evaluate the presence of anxiety and depression, the Impact of Event Scale Revised (IES-R) to assess the severity of intrusion, avoidance, and hypervigilance, and the Peritraumatic Dissociative Experiences Questionnaire (PDEQ) to quantify the traumatic dissociative symptomatology. Results: 31.5% of participants report a PDEQ score above the cutoff. The results indicated that dissociative symptomatology was positively correlated with HADS scores (HADS-Anxiety: r = 0.476, p dissociative symptomatology. The results converged on a three predictor model revealing that IES-R-Intrusion, IES-R-Avoidance, and IES-R-Hyperarousal accounted for 53.9% of the explained variance. Conclusion: These findings allow us to hypothesize a specific psychological reaction which may be ascribed to the traumatic spectrum within the context of cancer, emphasizing the close relationship between the origin of dissociative constituents which, according to the scientific literature, compose the traumatic experience. Our results have implications for understanding dissociative symptomatology in a cancer

  13. Prediction of iodide adsorption on oxides by surface complexation modeling with spectroscopic confirmation.

    Science.gov (United States)

    Nagata, Takahiro; Fukushi, Keisuke; Takahashi, Yoshio

    2009-04-15

    A deficiency in environmental iodine can cause a number of health problems. Understanding how iodine is sequestered by materials is helpful for evaluating and developing methods for minimizing human health effects related to iodine. In addition, (129)I is considered to be strategically important for safety assessment of underground radioactive waste disposal. To assess the long-term stability of disposed radioactive waste, an understanding of (129)I adsorption on geologic materials is essential. Therefore, the adsorption of I(-) on naturally occurring oxides is of environmental concern. The surface charges of hydrous ferric oxide (HFO) in NaI electrolyte solutions were measured by potentiometric acid-base titration. The surface charge data were analyzed by means of an extended triple-layer model (ETLM) for surface complexation modeling to obtain the I(-) adsorption reaction and its equilibrium constant. The adsorption of I(-) was determined to be an outer-sphere process from ETLM analysis, which was consistent with independent X-ray absorption near-edge structure (XANES) observation of I(-) adsorbed on HFO. The adsorption equilibrium constants for I(-) on beta-TiO(2) and gamma-Al(2)O(3) were also evaluated by analyzing the surface charge data of these oxides in NaI solution as reported in the literature. Comparison of these adsorption equilibrium constants for HFO, beta-TiO(2), and gamma-Al(2)O(3) based on site-occupancy standard states permitted prediction of I(-) adsorption equilibrium constants for all oxides by means of the Born solvation theory. The batch adsorption data for I(-) on HFO and amorphous aluminum oxide were reasonably reproduced by ETLM with the predicted equilibrium constants, confirming the validity of the present approach. Using the predicted adsorption equilibrium constants, we calculated distribution coefficient (K(d)) values for I(-) adsorption on common soil minerals as a function of pH and ionic strength.

  14. Multiphoton dissociative ionization of CS+

    Science.gov (United States)

    Rajput, Jyoti; Jochim, Bethany; Zohrabi, M.; Betsch, K. J.; Ablikim, U.; Berry, Ben; Severt, T.; Summers, A. M.; Armstrong, G. S. J.; Esry, B. D.; Carnes, K. D.; Ben-Itzhak, I.

    2015-05-01

    We have studied the dissociative photoionization of a CS+ molecular ion beam in the strong-field regime using process. Two prominent channels were observed: charge-symmetric dissociation, yielding C+ + S+, and charge-asymmetric dissociation, yielding C + S2+. The differences between these two channels with reference to their relative production probability, energetics, and angular distributions is the focus of this work. This work was supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy. BJ is also supported by DOE-SCGF (DE-AC05-06OR23100).

  15. A Spectroscopic Method for Determining Free Iodine in Iodinated Fatty-Acid Esters

    Science.gov (United States)

    Klyubin, V. V.; Klyubina, K. A.; Makovetskaya, K. N.

    2018-01-01

    It is shown that the concentration of free iodine in samples of iodinated fatty-acid esters can be measured using the electronic absorption spectra of their solutions in ethanol. The method proposed is rather simple in use and highly sensitive, allowing detection of presence of less than 10 ppm of free iodine in iodinated compounds. It is shown using the example of Lipiodol that this makes it possible to easily detect small amounts of free iodine in samples containing bound iodine in concentrations down to 40 wt %.

  16. Dissociative absorption: An empirically unique, clinically relevant, dissociative factor.

    Science.gov (United States)

    Soffer-Dudek, Nirit; Lassri, Dana; Soffer-Dudek, Nir; Shahar, Golan

    2015-11-01

    Research of dissociative absorption has raised two questions: (a) Is absorption a unique dissociative factor within a three-factor structure, or a part of one general dissociative factor? Even when three factors are found, the specificity of the absorption factor is questionable. (b) Is absorption implicated in psychopathology? Although commonly viewed as "non-clinical" dissociation, absorption was recently hypothesized to be specifically associated with obsessive-compulsive symptoms. To address these questions, we conducted exploratory and confirmatory factor analyses on 679 undergraduates. Analyses supported the three-factor model, and a "purified" absorption scale was extracted from the original inclusive absorption factor. The purified scale predicted several psychopathology scales. As hypothesized, absorption was a stronger predictor of obsessive-compulsive symptoms than of general psychopathology. In addition, absorption was the only dissociative scale that longitudinally predicted obsessive-compulsive symptoms. We conclude that absorption is a unique and clinically relevant dissociative tendency that is particularly meaningful to obsessive-compulsive symptoms. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Photo-electron spectroscopy using synchrotron radiation of molecular radicals and fragments produced by laser photo-dissociation

    International Nuclear Information System (INIS)

    Nahon, Laurent

    1991-01-01

    This research thesis reports the combined use of a laser and of a synchrotron radiation in order to respectively photo-dissociate a molecule and to photo-ionize fragments which are analysed by photo-electron spectroscopy. This association allows, on the one hand, radical photo-ionization to be studied, and, on the other hand, polyatomic molecule photo-dissociation to be studied. The author studied the photo-excitation and/or photo-ionization in layer 4d (resp. 3d) of atomic iodine (resp. bromine) produced almost complete laser photo-dissociation of I 2 (resp. Br 2 ). He discuses the processes of relaxation of transitions from valence 4d to 5p (resp. 3d to 4p) which occur either by direct self-ionization or by resonant Auger effect, and reports the study of photo-dissociation of s-tetrazine (C 2 N 4 H 2 ) [fr

  18. Geochemical Cycling of Iodine Species in Soils

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q; Moran, J E; Blackwood, V

    2007-08-23

    Iodine is an important element in studies of environmental protection and human health, global-scale hydrologic processes and nuclear nonproliferation. Biogeochemical cycling of iodine in soils is complex, because iodine occurs in multiple oxidation states and as inorganic and organic species that may be hydrophilic, atmophilic, and biophilic. In this study, we applied new analytical techniques to study the content and speciation of stable iodine in representative surface soils, and sorption and transport behavior of iodine species (iodide, iodate, and 4-iodoaniline) in sediments collected at numerous nuclear facilities in the United States, where anthropogenic {sup 129}I from prior nuclear fuel processing activities poses an environmental risk. The surface soil samples were chosen for their geographic locations (e.g., near the ocean or nuclear facilities) and for their differing physico-chemical characteristics (organic matter, texture, etc). Extracted solutions were analyzed by IC and ICP-MS methods to determine iodine concentrations and to examine iodine speciation (iodide, iodate, and organic iodine). In natural soils, iodine is mostly (nearly 90% of total iodine) present as organic species, while inorganic iodine becomes important (up to 50%) only in sediments with low organic matter. Results from laboratory column studies, aimed at examining transport of different iodine species, showed much greater retardation of 4-iodoaniline than iodide or iodate. Careful attention must be given to potential interconversion among species when interpreting the biogeochemical behavior of iodine in the environment. In addition to speciation, input concentration and residence time effects will influence the biogeochemical cycling of anthropogenic 129I deposited on surface soils.

  19. Neural complexity, dissociation, and schizophrenia

    Czech Academy of Sciences Publication Activity Database

    Bob, P.; Šusta, M.; Chládek, Jan; Glaslová, K.; Fedor-Ferybergh, P.

    2007-01-01

    Roč. 13, č. 10 (2007), HY1-5 ISSN 1234-1010 Institutional research plan: CEZ:AV0Z20650511 Keywords : neural complexity * dissociation * schizophrenia Subject RIV: FH - Neurology Impact factor: 1.607, year: 2007

  20. Dissociative Tendencies and Traffic Incidents

    Directory of Open Access Journals (Sweden)

    Valle, Virginia

    2012-01-01

    Full Text Available This paper analyses the relationship between dissociative experiences and road traffic incidents (crashes and traffic tickets in drivers (n=295 from Mar del Plata (Argentina city. A self-report questionnaire was applied to assess traffic crash involvement and sociodemographic variables. Dissociative tendencies were assessed by a modified version of the DES scale. To examine differences in DES scores tests of the difference of means were applied. Drivers who reported to be previously involved in traffic incidents obtained higher puntuations in the dissociative experiences scale than drivers who did not report such events. This result is observed for the total scale and for the three sub-scales (absorption, amnesia and depersonalization. However, differences appeared mainly for minor damage collisions. Further studies are needed to evaluate the role of dissociative tendencies as a risk factor in road traffic safety.

  1. Dissociative symptoms in pathological gambling.

    Science.gov (United States)

    Grant, Jon E; Kim, Suck Won

    2003-01-01

    Dissociation is increasingly being recognized as both a normal process and as a psychophysiological aspect of a number of mental disorders. The purpose of this investigation was to shed light on a possible link between dissociation and pathological gambling, a relatively common disorder whose phenomenology remains understudied. Thirty adult outpatients who met DSM-IV criteria for pathological gambling and had no comorbidity were administered the Dissociative Experiences Scale (DES). The pathological gamblers had DES scores that did not significantly differ from those reported by normal controls (t = -0.620; d.f. = 29; p = 0.540). Pathological gamblers do not appear to experience dissociative symptoms (as reflected on the DES) at a rate significantly different from those found in normal controls. Because pathological gamblers seeking medication treatment, as in this study, may differ from others with pathological gambling, further studies are needed. Copyright 2003 S. Karger AG, Basel

  2. Dissociation Energies of Diatomic Molecules

    International Nuclear Information System (INIS)

    Qun-Chao, Fan; Wei-Guo, Sun

    2008-01-01

    Molecular dissociation energies of 10 electronic states of alkali molecules of KH, 7 LiD, 7 LiH, 6 LiH, NaK, NaLi and NaRb are studied using the highest three accurate vibrational energies of each electronic state, and an improved parameter-free analytical formula which is obtained starting from the LeRoy–Bernstein vibrational energy expression near the dissociation limit. The results show that as long as the highest three vibrational energies are accurate, the current analytical formula will give accurate theoretical dissociation energies D e theory , which are in excellent agreement with the experimental dissociation energies D e expt . (atomic and molecular physics)

  3. Atrioventricular Dissociation after Electroconvulsive Therapy

    Directory of Open Access Journals (Sweden)

    Siegfried William Yu

    2011-01-01

    Full Text Available Electroconvulsive therapy (ECT is increasingly used as a treatment for psychiatric disorders. Cardiac effects are the principal cause of medical complications in these patients. We report a case of atrioventricular (AV dissociation that occurred after ECT that was treated with pacemaker implantation. The mechanisms contributing to the onset of AV dissociation in this patient, and the management and rationale for device therapy, in light of the most recent guidelines, are reviewed.

  4. Thermodynamic properties of dissociated steam

    Science.gov (United States)

    Aminov, R. Z.; Gudym, A. A.

    2017-11-01

    In connection with the development of hydrogen technologies and the generation of dissociated steam as a result of the oxidation of hydrogen in an oxygen environment, it became necessary to determine the calorific parameters of dissociated steam. In the existing tables, the caloric parameters of dissociated steam are presented at a reference temperature of 0 K. By contrast, the authors have developed tables of dissociated steam using a reference temperature of 0°C, within the pressure range 0.01–20.0 MPa and the temperature range 1250–4000 K, along with a system of equations for the industrial calculation of the properties of dissociated steam within the temperature range 1250–2300 K and pressure range 0.01–10.0 MPa, followed by a temperature range of 2200–3600 K. During the dissociation of steam, a mixture of eight components are formed including hydrogen H, oxygen O, radicals OH and HO2, molecules of hydrogen H2, oxygen O2, steam H2O, and hydrogen peroxide H2O2. All existing tables of the properties of dissociated steam are based on a mixture of six components: H2, O2, OH, H, O, and H2O. For evaluate whether this is an oversimplification, the composition of the mixture comprising all eight components was calculated, taking into account additional chemical reactions for the formation of HO2 and H2O2. At a pressure of 0.01 MPa, the maximum mole fraction of HO2 was 2.8·10‑5 at a temperature of 3000 K, and at a pressure of 10 MPa, the maximum mole fraction was 5·10‑5 at a temperature of 4000 K. The mole fraction of H2O2 was much lower. Thus at temperatures up to 3000 K, calculations of the properties of dissociated steam are restricted to six components.

  5. Water aggregation and dissociation on the ZnO(101[combining macron]0) surface.

    Science.gov (United States)

    Kenmoe, Stephane; Biedermann, P Ulrich

    2017-01-04

    A comprehensive search for stable structures in the low coverage regime (0-1 ML) and at 2 ML and 3 ML using DFT revealed several new aggregation states of water on the non-polar ZnO(101[combining macron]0) surface. Ladder-like structures consisting of half-dissociated dimers, arranged side-by-side along the polar axis, constitute the most stable aggregate at low coverages (≤1 ML) with a binding energy exceeding that of the monolayer. At coverages beyond the monolayer - a regime that has hardly been studied previously - a novel type of structure with a continuous honeycomb-like 2D network of hydrogen bonds was discovered, where each surface oxygen atom is coordinated by additional H-bonding water molecules. This flat double-monolayer has a relatively high adsorption energy, every zinc and oxygen atom is 4-fold coordinated and every hydrogen atom is engaged in a hydrogen bond. Hence this honeycomb double monolayer offers no H-bond donor or acceptor sites for further growth of the water film. At 3 ML coverage, the interface restructures forming a contact layer of half-dissociated water dimers and a liquid-like overlayer of water attached by hydrogen bonds. The structures and their adsorption energies are analysed to understand the driving forces for aggregation and dissociation of water on the surface. We apply a decomposition scheme based on a Born-Haber cycle, discussing difficulties that may occur in applying such an analysis to the adsorption of dissociated molecules and point out alternatives to circumvent the bias against severely stretched bonds. Water aggregation on the ZnO surface is favoured by direct water-water interactions including H-bonds and dipole-dipole interactions and surface- or adsorption-mediated interactions including enhanced water-surface interactions and reduced relaxations of the water molecules and surface. While dissociation of isolated adsorbed molecules is unfavourable, partial or even full dissociation is preferred for aggregates

  6. 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.

  7. Iodine in drinking water varies by more than 100-fold in Denmark. Importance for iodine content of infant formulas

    DEFF Research Database (Denmark)

    Pedersen, K M; Laurberg, P; Nøhr, S

    1999-01-01

    The iodine intake level of the population is of major importance for the occurrence of thyroid disorders in an area. The aim of the present study was to evaluate the importance of drinking water iodine content for the known regional differences in iodine intake in Denmark and for the iodine content...... of infant formulas. Iodine in tap water obtained from 55 different locations in Denmark varied from ... the iodine content of tap water with a high initial iodine concentration. A statistically significant correlation was found between tap water iodine content today and the urinary iodine excretion measured in 41 towns in 1967 (r=0.68, P

  8. Dissociative disorders in DSM-5.

    Science.gov (United States)

    Spiegel, David; Lewis-Fernández, Roberto; Lanius, Ruth; Vermetten, Eric; Simeon, Daphne; Friedman, Matthew

    2013-01-01

    The rationale, research literature, and proposed changes to the dissociative disorders and conversion disorder in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) are presented. Dissociative identity disorder will include reference to possession as well as identity fragmentation, to make the disorder more applicable to culturally diverse situations. Dissociative amnesia will include dissociative fugue as a subtype, since fugue is a rare disorder that always involves amnesia but does not always include confused wandering or loss of personality identity. Depersonalization disorder will include derealization as well, since the two often co-occur. A dissociative subtype of posttraumatic stress disorder (PTSD), defined by the presence of depersonalization or derealization in addition to other PTSD symptoms, is being recommended, based upon new epidemiological and neuroimaging evidence linking it to an early life history of adversity and a combination of frontal activation and limbic inhibition. Conversion disorder (functional neurological symptom disorder) will likely remain with the somatic symptom disorders, despite considerable dissociative comorbidity.

  9. Dissociative Experiences and Vividness of Auditory Imagery

    Science.gov (United States)

    Pérez-Fabello, María José; Campos, Alfredo

    2017-01-01

    The relationship between dissociation and auditory imagery were assessed, 2 variables that sometime influence on artistic creativity. A total of 170 fine arts undergraduates (94 women and 76 men) received 2 dissociation questionnaires--the Dissociative Ability Scale (DAS), and the Dissociative Experiences Scale (DES)--and 2 auditory imagery…

  10. Estimation of iodine intake from various urinary iodine measurements in population studies

    DEFF Research Database (Denmark)

    Vejbjerg, P.; Knudsen, N.; Perrild, H.

    2009-01-01

    Background: Iodine intake is often measured by a surrogate measure, namely urine iodine excretion as almost all ingested iodine is excreted in the urine. However, the methods for urine collection and the reporting of the results vary. These methods, and their advantages and disadvantages......, are considered in this article. Summary: There are two main ways in which urine can be collected for iodine measurement. The first is the collection of urine over a period, usually 24 hours. The second is the collection of a spot urinary sample. Urinary iodine values can be expressed as the content...... or concentration and reported without modification or as a function of creatinine in the same sample. The 24-hour urine for iodine measurement is often considered as the “reference standard” for giving a precise estimate of the individual iodine excretion and thereby iodine intake. As 24-hour collections...

  11. Iodine Absorption Cells Purity Testing

    Czech Academy of Sciences Publication Activity Database

    Hrabina, Jan; Zucco, M.; Philippe, Ch.; Pham, Minh Tuan; Holá, Miroslava; Acef, O.; Lazar, Josef; Číp, Ondřej

    2017-01-01

    Roč. 17, č. 1 (2017), s. 1-13, č. článku 17010102. ISSN 1424-8220 R&D Projects: GA ČR GA15-18430S; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : iodine cells * absorption spectroscopy * laser spectroscopy * laser standards * frequency stability Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.677, year: 2016

  12. Delayed development, death and abnormal thyroglobulin in rats maintained on low-iodine diets

    International Nuclear Information System (INIS)

    Van Middlesworth, L.

    1976-01-01

    Rats weaned on Remington Low Iodine Diet (0.006 to 0.009 μgI/g) grew poorly, were very slow to breed, and 83% of their pups died in the neonatal period. A large iodide supplement (100μgI/d) improved growth of the females to almost normal but did not improve growth of males. With the iodide supplement they bred at an earlier age than rats fed the low iodide Remington diet but still 73% of the pups died before weaning. The addition of a vitamin mixture (biotin, vitamin B 12 , E, patothenic acid, riboflavin, thiamine and pyridoxine) to Remington Diet resulted in delayed pregnancies but 86% survival of offspring. A more nutritious low-iodine diet with a 'complete' mineral and vitamin supplement improved growth and survival, and the litters were delivered at the normal time. However, this more complete diet contained more iodine than the Remington diet. During the neonatal period, all the low iodine diets resulted in offspring that were unable to make T 3 as readily as adults fed the same diet. Pups from dams fed the Remington diet had thyroblobulin with lower sedimentation constants (18S and 12S) than was found in normal newborns. This unfolded and dissociated thyroglobulin may be an inadequate source of thyroid hormones, but it may hydrolyse more rapidly than normal 19S thyroglobulin. It is concluded that rats raised on a diet severely deficient in iodine were unable to litter until they were older than normal rats, and the survival of the offspring was poor unless the diet was supplemented with a vitamin mixture. The synthesis of thyroid hormones in low iodine neonatal rats was more severely impaired than in adults. (author)

  13. Iodine chemistry in a reactor regulation

    Energy Technology Data Exchange (ETDEWEB)

    Powers, D.A. [Nuclear Regulatory Commission, Washington, DC (United States). Advisory Committee on Reactor Safeguards

    1996-12-01

    Radioactive iodine has always been an important consideration in the regulation of nuclear power reactors to assure the health and safety of the public. Regulators adopted conservatively bounding predictions of iodine behavior in the earliest days of the development of nuclear power because there was so little known about either accidents or the chemistry of iodine. Today there is a flood of new information and understanding of the chemistry of iodine under reactor accident conditions. This paper offers some thoughts on how the community of scientists engaged in the study of iodine chemistry can present the results of their work so that it is more immediately adopted by the regulator. It is suggested that the scientific community consider the concept of consensus standards so effectively used within the engineering community to define the status of the study of radioactive iodine chemistry for reactor safety. (author) 9 refs.

  14. Discovery and Early Uses of Iodine

    Science.gov (United States)

    Rosenfeld, Louis

    2000-08-01

    The ancient Chinese recognized goiter and the therapeutic effects of burnt sponge and seaweed in reducing its size or causing its disappearance. The modern use of iodine in the prevention of goiter dates from 1830, when it was proposed that goiter is an iodine deficiency disease due to lack of iodine in the water supply. But unfavorable symptoms of iodism were frequent owing to overenthusiastic use and overdose of iodine. Consequently, iodide prophylaxis was discredited and abandoned. The presence of iodine in organic combination as a normal constituent of the thyroid was established in 1896 and the use of iodine in treatment and prevention of goiter was revived. In 1917 the general use of iodized salt in goitrous areas was shown to be effective in preventing simple endemic goiter.

  15. Iodine frequency references for space

    International Nuclear Information System (INIS)

    Schuldt, Thilo; Braxmaier, Claus; Döringshoff, Klaus; Peters, Achim; Oswald, Markus; Johann, Ulrich

    2017-01-01

    Optical frequency references are a key element for the realization of future space missions. They are needed for missions related to tests of fundamental physics, gravitational wave detection, Earth observation and navigation and ranging. In missions such as GRACE follow-on or LISA the optical frequency reference is used as light source for high-sensitivity inter-satellite distance metrology. While cavity-based systems are current baseline e.g. for LISA, frequency stabilization on a hyperfine transition in molecular iodine near 532 nm is a promising alternative. Due to its absolute frequency, iodine standards crucially simplify the initial spacecraft acquisition procedures. Current setups fulfill the GRACE-FO and LISA frequency stability requirements and are realized near Engineering Model level. We present the current status of our developments on Elegant Breadboard (EBB) and Engineering Model (EM) level taking into account specific design criteria for space compatibility such as compactness (size iodine spectroscopy EM: 38 × 18 × 10 cm 3 ) and robustness. Both setups achieved similar frequency stabilities of ∼ 1 · 10 −14 at an integration time of 1 s and below 5 · 10 −15 at integration times between 10 s and 1000 s. Furthermore, we present an even more compact design currently developed for a sounding rocket mission with launch in 2017. (paper)

  16. Iodine frequency references for space

    Science.gov (United States)

    Schuldt, Thilo; Döringshoff, Klaus; Oswald, Markus; Johann, Ulrich; Peters, Achim; Braxmaier, Claus

    2017-05-01

    Optical frequency references are a key element for the realization of future space missions. They are needed for missions related to tests of fundamental physics, gravitational wave detection, Earth observation and navigation and ranging. In missions such as GRACE follow-on or LISA the optical frequency reference is used as light source for high-sensitivity inter-satellite distance metrology. While cavity-based systems are current baseline e.g. for LISA, frequency stabilization on a hyperfine transition in molecular iodine near 532 nm is a promising alternative. Due to its absolute frequency, iodine standards crucially simplify the initial spacecraft acquisition procedures. Current setups fulfill the GRACE-FO and LISA frequency stability requirements and are realized near Engineering Model level. We present the current status of our developments on Elegant Breadboard (EBB) and Engineering Model (EM) level taking into account specific design criteria for space compatibility such as compactness (size iodine spectroscopy EM: 38 × 18 × 10 cm3) and robustness. Both setups achieved similar frequency stabilities of ˜ 1 · 10-14 at an integration time of 1 s and below 5 · 10-15 at integration times between 10 s and 1000 s. Furthermore, we present an even more compact design currently developed for a sounding rocket mission with launch in 2017.

  17. Iodine Absorption Cells Purity Testing

    Directory of Open Access Journals (Sweden)

    Jan Hrabina

    2017-01-01

    Full Text Available This article deals with the evaluation of the chemical purity of iodine-filled absorption cells and the optical frequency references used for the frequency locking of laser standards. We summarize the recent trends and progress in absorption cell technology and we focus on methods for iodine cell purity testing. We compare two independent experimental systems based on the laser-induced fluorescence method, showing an improvement of measurement uncertainty by introducing a compensation system reducing unwanted influences. We show the advantages of this technique, which is relatively simple and does not require extensive hardware equipment. As an alternative to the traditionally used methods we propose an approach of hyperfine transitions’ spectral linewidth measurement. The key characteristic of this method is demonstrated on a set of testing iodine cells. The relationship between laser-induced fluorescence and transition linewidth methods will be presented as well as a summary of the advantages and disadvantages of the proposed technique (in comparison with traditional measurement approaches.

  18. Measurement of thyroid volume, iodine concentration and total iodine content by CT and its clinical significance

    International Nuclear Information System (INIS)

    Nakaji, Shunsuke; Imanishi, Yoshimasa; Okamoto, Kyouko; Shinagawa, Toshihito

    2007-01-01

    Recently, Imanishi et al have developed new CT software for quantitative in vivo measurement of thyroid iodine. Using a CT system with the software, we measured volume, iodine concentration and total iodine content of thyroids in 63 controls and 435 patients with various diffuse thyroid diseases and thyroid nodules. In controls, all of them showed no difference between the sexes. Although the iodine concentration of the thyroid showed no difference among children, adults and seniles, the volume and total iodine content of the thyroid appeared smaller in children and seniles than in adults. In addition, although the volume and iodine concentration of the thyroid had two peaks in distribution, the total iodine content had almost normal distribution. Normal range of volume, iodine concentration and total iodine content in adults were 5.2-15.5 cm 3 , 0.28831-0.85919 mg/cm 3 and 2.35-11.69 mg, respectively. In thyroid nodule, there is no significant difference in volume, iodine concentration and total iodine content between benign and malignant nodules. All nodules with iodine concentration of less than 0.00007 mg/cm 3 were benign. No thyroid was higher in iodine concentration than the normal range although the thyroid was lower in 78.7% of patients with diffuse thyroid diseases. In all thyroids with increasing iodine concentration and total iodine content in medication course, thyroidal symptoms and signs were uncontrollable by the medication. In 43.8% of patients with long-period systemic diseases, the thyroid showed abnormality in any of the three. We concluded that quantitative in vivo measurement of thyroid iodine by CT could assist the diagnosis of thyroid diseases and decision of therapeutic methods. (author)

  19. Local radiolytic effectiveness of Auger electrons of iodine-125 in benzene-iodine solutions

    International Nuclear Information System (INIS)

    Uenak, P.; Uenak, T.

    1987-01-01

    High radiotoxicity of iodine-125 has been mainly attributed to the local radiolytic effects of Auger electrons on biological systems. In the present study, experimental and theoretical results are compared. The agreement between the experimental and theoretical results explains that the energy absorption of iodine aggregates has an important role in the radiolytic effectiveness of Auger electrons and iodine-125 in benzene-iodine solutions. (author) 18 refs.; 3 figs

  20. Molecular environment of iodine in naturally iodinated humic substances: Insight from X-ray absorption spectroscopy

    International Nuclear Information System (INIS)

    Schlegel, Michel L.; Mercier-Bion, Florence; Barre, Nicole; Reiller, Pascal; Moulin, Valerie

    2006-01-01

    The molecular environment of iodine in reference inorganic and organic compounds, and in dry humic and fulvic acids (HAs and FAs) extracted from subsurface and deep aquifers was probed by iodine L-3-edge X-ray absorption spectroscopy. The X-ray absorption near-edge structure (XANES) of iodine spectra from HAs and FAs resembled those of organic references and displayed structural features consistent with iodine forming covalent bonds with organic molecules. Simulation of XANES spectra by linear combination of reference spectra suggested the predominance of iodine forming covalent bonds to aromatic rings (aromatic-bound iodine). Comparison of extended X-ray absorption fine structure (EXAFS) spectra of reference and samples further showed that iodine was surrounded by carbon shells at distances comparable to those for references containing aromatic-bound iodine. Quantitative analysis of EXAFS spectra indicated that iodine was bound to about one carbon at a distance d(I-C) of 2.01(4)-2.04(9) angstrom, which was comparable to the distances observed for aromatic-bound iodine in references (1.99(1)-2.07(6) angstrom), and significantly shorter than that observed for aliphatic-bound iodine (2.15(2)-2.16(2) angstrom). These results are in agreement with previous conclusions from X-ray photoelectron spectroscopy and from electro-spray ionization mass spectrometry. These results collectively suggest that the aromatic-bound iodine is stable in the various aquifers of this study. (authors)

  1. Iodine deficiency in pregnancy and the effects of maternal iodine supplementation on the offspring: a review

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2009-01-01

    The World Health Organization (WHO) recently increased their recommended iodine intake during pregnancy from 200 to 250 µg/d and suggested that a median urinary iodine (UI) concentration of 150-249 µg/L indicates adequate iodine intake in pregnant women. Thyrotropin concentrations in blood collected

  2. Iodine requirements and the risks and benefits of correcting iodine deficiency in populations

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2008-01-01

    Iodine deficiency has multiple adverse effects on growth and development due to inadequate thyroid hormone production that are termed the iodine deficiency disorders (IDD). IDD remains the most common cause of preventable mental impairment worldwide. IDD assessment methods include urinary iodine

  3. Iodine: It's Important in Patients that Require Parenteral Nutrition

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2009-01-01

    Iodine deficiency has multiple adverse effects on growth and development because of inadequate thyroid hormone production. Four methods are generally recommended for assessment of iodine nutrition: urinary iodine concentration, thyroid size, and blood concentrations of thyroid-stimulating hormone

  4. Iodine-129 in thyroids of grazing animals

    International Nuclear Information System (INIS)

    Ballad, R.V.; Holman, D.W.; Hennecke, E.W.; Johnson, J.E.; Manuel, O.K.; Nicholson, L.M.

    1976-01-01

    A combination of neutron activation and mass spectrometry has been used to determine the concentrations of fissiogenic 129 I and stable 127 I in thyroids of grazing animals and in mineral iodine. The 129 I/ 127 I ratios are lowest in mineral iodine and in a given area lower in cow thyroids than in deer thyroids. Near saturation levels of mineral iodine in commercial feeds and salt licks may account for differences in the 129 I levels of cows and deer. Values of the 129 I/ 127 I ratio in deer appear to vary inversely with the iodine concentration of the thyroid. (author)

  5. Hygienic assessment of radioactive iodine isotopes

    International Nuclear Information System (INIS)

    Vasilenko, I.Ya.

    1987-01-01

    Sources of radioactive iodine isotopes and their biological significance depending on the way of intake are discussed. The degree of food contamination by radioactive iodine as well as products, which serve as the source of its intake into the human body, and results of their processing are considered. The danger of radioactive iodine intake by different groups of population as well as thyroid irradiation effects are discussed. Description of activities, directed to the human body protection against radioactive iodine and assessment of these protection measures efficiency is presented

  6. Absorption spectrum of Iodine around 5915 A

    International Nuclear Information System (INIS)

    1990-01-01

    The iodine absorption spectrum around 5915 A is of interest for many authors especially the hyperfine structure of the iodine line. Lodine absorption spectrum was obtained due to the interaction of iodine vapour with dye laser [(R6G) (0.5A) scanning range around 5915 A] which is pumped by(Ar + )laser absorption spectrum. The decrease in the peak of the transmission line around 5915 A shows the signal futher decreased by heating the iodine cell. This analysis has been done using a monochromator

  7. Water Adsorption on TiO2

    DEFF Research Database (Denmark)

    Hammer, Bjørk; Wendt, Stefan; Besenbacher, Flemming

    2010-01-01

    Scanning Tunneling Microscopy (STM) studies and Density Functional Theory (DFT) investigations of the interaction of water with the rutile TiO2 (110) surface are summarized. From high-resolution STM the following reactions have been revealed: water adsorption and diffusion in the Ti troughs, water...... dissociation in bridging oxygen vacancies, assembly of adsorbed water monomers into rapidly diffusing water dimers, and formation of water dimers by reduction of oxygen molecules. The STM results are rationalized based on DFT calculations, revealing the bonding geometries and reaction pathways of the water...

  8. Iodine content in drinking water and other beverages in Denmark

    DEFF Research Database (Denmark)

    Rasmussen, Lone Banke; Larsen, Erik Huusfeldt; Ovesen, L.

    2000-01-01

    Objective: To investigate the variation in iodine content in drinking water in Denmark and to determine the difference in iodine content between organic and non-organic milk. Further, to analyse the iodine content in other beverages. Design and setting: Tap water samples were collected from 41...... geographical (and seasonal) variations in iodine concentrations were found in different beverages supplying an appreciable part of the iodine in the Danish diet. This knowledge is important when calculating the iodine intake from dietary intake studies....

  9. Water adsorption on the stoichiometric and defected Fe(110) surfaces

    Science.gov (United States)

    Ossowski, Tomasz; Da Silva, Juarez L. F.; Kiejna, Adam

    2018-02-01

    The adsorption of water molecules on defect-free (called here as stoichiometric) and defected Fe(110) surfaces has been investigated using density functional theory (DFT) calculations. It is found that on the stoichiometric surface H2O molecules do not dissociate spontaneously and adsorbs flat on top of the surface Fe atom. By studying different orientations of the flat lying molecule in different adsorption sites it is found that some of them are degenerated in energy thus suggesting a possibility of molecule rotation around direction normal to the surface. At the vacancy defected surface the water molecule favors undercoordinated adsorption sites at or next to the vacancy edge - not the ones in the stoichiometric region of the surface. Moreover, similarly to the stoichiometric surface, at defected one some different configurations are degenerated in energy, making possible molecules circling around the vacancy. The influence of the van der Waals interactions on the adsorption properties of the system is also considered and discussed.

  10. FDA regulations regarding iodine addition to foods and labeling of foods containing added iodine12

    Science.gov (United States)

    Trumbo, Paula R

    2016-01-01

    The US Food and Drug Administration (FDA) regulates the addition of iodine to infant formulas, the iodization of salt, and the addition of salt and iodine to foods. The required amount of iodine in infant formulas is based on caloric content, and the label must provide the iodine content per 100 kcal. Cuprous iodide and potassium iodide may be added to table salt as a source of dietary iodine at a maximum amount of 0.01%; if added, the label must indicate that the salt is iodized. Table salt to which iodine has not been added must bear the statement, “This salt does not supply iodide, a necessary nutrient.” If a nutrient is to be appropriately added to a food for the purpose of correcting a dietary insufficiency, there should be sufficient scientific information available to demonstrate a nutritional deficiency and/or identify a public health problem. Furthermore, the population groups that would benefit from the proposed fortification should be identified. If iodine is added to a food, the percent Daily Value of iodine must be listed. There are no FDA regulations governing ingredient standards for dietary supplements. As a result, some dietary supplements include iodine and others do not. If a supplement contains iodine, the Supplement Facts label must list iodine as a nutrient ingredient. If iodine is not listed on the Supplement Facts label, then it has not been added. There are similarities between the FDA, which establishes US food regulations and policies, and the Codex Alimentarius (Codex), which develops international food standards and guidelines under the aegis of the FAO and the WHO. Both the FDA and Codex call for the labeling of table salt to indicate fortification with iodine, voluntary labeling of iodine on foods, and a Daily Value (called a Nutrient Reference Value by Codex) of 150 μg for iodine. PMID:27534626

  11. Serum thyroglobulin and urinary iodine concentration are the most appropriate indicators of iodine status and thyroid function under conditions of increasing iodine supply in schoolchildren in Benin

    NARCIS (Netherlands)

    van den Briel, T.; West, C. E.; Hautvast, J. G.; Vulsma, T.; de Vijlder, J. J.; Ategbo, E. A.

    2001-01-01

    Iodine deficiency control programs have greatly reduced iodine deficiency disorders worldwide. For monitoring changes in iodine status, different indicators may be used. The aim of this study was to evaluate the suitability of indicators of iodine status and thyroid function, thyroglobulin (Tg),

  12. adsorption isotherm a

    African Journals Online (AJOL)

    ADOWIE PERE

    sawmill factory waste: adsorption isotherm and kinetic studies. KELLE, HI. Department of Pure and ... Keywords: Sawdust, crude oil, adsorption kinetics, oil sorption capacity, sorbed oil recoverability, adsorption isotherm. Key methods available for ..... of Basic Dyes from Aqueous Solution. By Sphagnum Moss Peat, Can.

  13. Historical aspects of iodine deficiency control.

    Science.gov (United States)

    Vanderpas, Jean-Baptiste; Moreno-Reyes, Rodrigo

    2017-04-01

    In 1895, iodine was characterized as an essential element of thyroid tissue by Baumann. The efficacy of iodine to prevent goiter was demonstrated by Marine in Northern USA in 1916-1920. Severe endemic goiter and cretinism had been almost entirely eliminated from continental Western Europe and Northern America before the 1930's; however large populations elsewhere and even some places in Western Europe (Sicily) were still affected up to the 2000's. Public health consequences of iodine deficiency are not limited to endemic goiter and cretinism. Iodine deficiency disorders include also increased neonatal death rate and decreased intellectual development, although these consequences are not included in the current estimation of the Global Burden Disease related to iodine deficiency. Severe iodine deficiency as a public health problem is now largely under control worldwide, but can still affect isolated places, in hard-to-reach and/or politically neglected populations. We emphasize the importance of maintaining international cooperation efforts, in order to monitor iodine status where iodine deficiency is now adequately controlled, and identify at-risk population where it is not. The goal should be now global eradication of severe iodine deficiency. Commercial distribution of iodized salt remains the most appropriate strategy. A randomized clinical trial in New Guinea clearly showed in the 1970's that correcting severe iodine deficiency early in pregnancy prevents endemic neurological cretinism. This supports the essential role of thyroid hormones of maternal origin on the normal fetal development, during the first trimester of pregnancy (i.e. when fetal thyroid is still not functional). A randomized clinical trial in Congo (RD) in the 1970's also showed that correcting severe iodine deficiency during pregnancy prevents myxœdematous cretinism, particularly prevalent in affected Congolese areas.

  14. Consuming iodine enriched eggs to solve the iodine deficiency endemic for remote areas in Thailand

    Directory of Open Access Journals (Sweden)

    Teeyapant Punthip

    2010-12-01

    Full Text Available Abstract Background Evidence showed that the occurrence of iodine deficiency endemic areas has been found in every provinces of Thailand. Thus, a new pilot programme for elimination of iodine deficiency endemic areas at the community level was designed in 2008 by integrating the concept of Sufficient Economic life style with the iodine biofortification of nutrients for community consumption. Methods A model of community hen egg farm was selected at an iodine deficiency endemic area in North Eastern part of Thailand. The process for the preparation of high content iodine enriched hen food was demonstrated to the farm owner with technical transfer in order to ensure the sustainability in the long term for the community. The iodine content of the produced iodine enriched hen eggs were determined and the iodine status of volunteers who consumed the iodine enriched hen eggs were monitored by using urine iodine excretion before and after the implement of iodine enrichment in the model farm. Results The content of iodine in eggs from the model farm were 93.57 μg per egg for the weight of 55 - 60 g egg and 97.76 μg for the weight of 60 - 65 g egg. The biological active iodo-organic compounds in eggs were tested by determination of the base-line urine iodine of the volunteer villagers before and after consuming a hard boiled iodine enriched egg per volunteer at breakfast for five days continuous period in 59 volunteers of Ban Kew village, and 65 volunteers of Ban Nong Nok Kean village. The median base-line urine iodine level of the volunteers in these two villages before consuming eggs were 7.00 and 7.04 μg/dL respectively. After consuming iodine enriched eggs, the median urine iodine were raised to the optimal level at 20.76 μg/dL for Ban Kew and 13.95 μg/dL for Ban Nong Nok Kean. Conclusions The strategic programme for iodine enrichment in the food chain with biological iodo-organic compound from animal origins can be an alternative method to

  15. Adsorption Model for Off-Gas Separation

    Energy Technology Data Exchange (ETDEWEB)

    Veronica J. Rutledge

    2011-03-01

    The absence of industrial scale nuclear fuel reprocessing in the U.S. has precluded the necessary driver for developing the advanced simulation capability now prevalent in so many other countries. Thus, it is essential to model complex series of unit operations to simulate, understand, and predict inherent transient behavior and feedback loops. A capability of accurately simulating the dynamic behavior of advanced fuel cycle separation processes will provide substantial cost savings and many technical benefits. The specific fuel cycle separation process discussed in this report is the off-gas treatment system. The off-gas separation consists of a series of scrubbers and adsorption beds to capture constituents of interest. Dynamic models are being developed to simulate each unit operation involved so each unit operation can be used as a stand-alone model and in series with multiple others. Currently, an adsorption model has been developed in gPROMS software. Inputs include gas stream constituents, sorbent, and column properties, equilibrium and kinetic data, and inlet conditions. It models dispersed plug flow in a packed bed under non-isothermal and non-isobaric conditions for a multiple component gas stream. The simulation outputs component concentrations along the column length as a function of time from which the breakthrough data is obtained. It also outputs temperature along the column length as a function of time and pressure drop along the column length. Experimental data will be input into the adsorption model to develop a model specific for iodine adsorption on silver mordenite as well as model(s) specific for krypton and xenon adsorption. The model will be validated with experimental breakthrough curves. Another future off-gas modeling goal is to develop a model for the unit operation absorption. The off-gas models will be made available via the server or web for evaluation by customers.

  16. High coverage water adsorption on the CuO(111) surface

    Science.gov (United States)

    Yu, Xiaohu; Zhang, Xuemei; Wang, Hongtao; Feng, Gang

    2017-12-01

    Water adsorption on the CuO(111) surface at different coverage has been systematically studied by spin-polarized density functional theory calculations (GGA+U) and atomic thermodynamics. Both molecular and dissociative adsorptions are studied. It is found that H2O molecule can chirally adsorb on CuO(111) surface which maybe play an important role in catalysis field. Molecular H2O adsorption is preferred for one H2O molecule, while mixed molecular and dissociative coadsorption is preferred on CuO(111) surface for two, three and four H2O molecules. Molecular and dissociative H2O adsorption can coexist at high temperature by using Boltzmann statistics. The phase diagram shows that only three surface configurations are stable thermodynamically: clean CuO(111) surface, two H2O and four H2O adsorption. The surface uncoordinated copper and oxygen atoms, and hydrogen bonding contribute to the adsorption energies. H2O adsorption mechanism has been analyzed by projected density of states (PDOS).

  17. Environmental sciences: general. 1. Evaluation of Iodine Reactions with Nuclear Aerosols by DRIFT

    International Nuclear Information System (INIS)

    Riggs, C.A.; Tompson, R.V.; Ghosh, T.K.; Loyalka, S.K.

    2001-01-01

    Nuclear source term computations require databases for iodine vapor reactions with cesium compounds. We have explored measurements of iodine vapor [I 2(g) ] reactions with cesium carbonate particles [CsCO 3(s) ] using diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy in the far infrared region for iodine vapor concentrations typical of post-transient conditions in a pressurized water reactor containment. Cesium hydroxide (CsOH) in aerosol form is likely a significant source of radio-cesium released during a reactor transient. As shown in Eq. (1), CsOH (s) particles can combine with iodine gas to form cesium iodide [CsI (s) ] particles. Equations (2) and (3) present a two-step method where the CsOH (s) particles combine with carbon dioxide [CO 2(g) ] found in air to form Cs 2 CO 3(s) particles, which then react with iodine gas to form CsI (s) particles: I 2(g) + 4CsOH (s) ↔ 2CsI (s) 12CsO (s) 12H 2 O (l) , (1) CO 2(g) 12CsOH (s) ↔ Cs 2 CO 3(s) + H 2 O, (2) and Cs 2 CO 3(s) 13I 2(g) ↔ 5CsI (s) + CsIO 3(s) + 3CO 2(g) . (3) We elected to study reactions with Cs 2 CO 3(s) rather than CsOH (s) particles because of significant analytical and handling challenges with the DRIFT attachment presented by the corrosive characteristics of CsOH (s) particles. Physical modifications to the DRIFT attachment, in addition to improved handling practices, need to be evaluated prior to proceeding with the study of CsOH (s) by this method. The reaction of cesium carbonate agglomerates with iodine could occur by surface adsorption and/or absorption. Physical adsorption depends on the surface area and porosity of the solid material. Chemical adsorption depends on the chemical properties of both the gas and the solid material. Beahm et al. previously used classical wet chemical methods to monitor the reaction products after the reaction occurred. The use of DRIFT allows the study of the predicted physical and chemical adsorption occurring on the Cs 2 CO 3(s) surface

  18. Methodology study for fixation of radioactive iodine in polymeric substrate for brachytherapy sources

    International Nuclear Information System (INIS)

    Rodrigues, Bruna T.; Rostelato, Maria Elisa C.M.; Souza, Carla D.; Tiezzi, Rodrigo; Souza, Daiane B. de; Benega, Marcos A.G.; Souza, Anderson S. de; Peleias Junior, Fernando S.; Zeituni, Calos A.; Fernandes, Vagner; Melo, Emerson Ronaldo de; Camargo, Anderson Rogerio de

    2015-01-01

    Cancer is now the second leading cause of death by disease in several countries, including Brazil. Prostate cancer is the most common among men. Brachytherapy is a modality of radiotherapy in which radioactive seeds are placed inside or in contact with the organ to be treated. The most widely used radioisotope in prostate brachytherapy is Iodine-125 which is presented fixated on a silver substrate that is subsequently placed inside a titanium capsule. A large dose of radiation is released only in the targeted tumor protecting healthy surrounding tissues. The technique requires the application of 80 - 120 seeds per patient. The implants of seeds have low impact and non-surgical procedures. Most patients can return to normal life within three days with little or no pain. This work proposes an alternative to the seeds that have already been developed, in order to reduce the cost by obtaining a better efficiency on fixing the radioactive iodine onto the epoxy resin. Methods have been developed to perform the fixation of Iodine-125 onto polymeric substrates. The parameters analyzed were the immersion time, type of static or dynamic reaction, concentration of the adsorption solution, the specific activity of the radioactive source, the need for carrier and chemical form of the radioactive Iodine. These experiments defined the most effective method to fixate the Iodine onto the polymeric material (epoxy resin), the Iodine activity in the polymeric substrate, the activity of the distribution of variation in a plot of polymeric cores and the efficiency of the epoxy resin to seal the seed. (author)

  19. Methodology study for fixation of radioactive iodine in polymeric substrate for brachytherapy sources

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Bruna T.; Rostelato, Maria Elisa C.M.; Souza, Carla D.; Tiezzi, Rodrigo; Souza, Daiane B. de; Benega, Marcos A.G.; Souza, Anderson S. de; Peleias Junior, Fernando S.; Zeituni, Calos A.; Fernandes, Vagner; Melo, Emerson Ronaldo de; Camargo, Anderson Rogerio de, E-mail: bteigarodrigues@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Cancer is now the second leading cause of death by disease in several countries, including Brazil. Prostate cancer is the most common among men. Brachytherapy is a modality of radiotherapy in which radioactive seeds are placed inside or in contact with the organ to be treated. The most widely used radioisotope in prostate brachytherapy is Iodine-125 which is presented fixated on a silver substrate that is subsequently placed inside a titanium capsule. A large dose of radiation is released only in the targeted tumor protecting healthy surrounding tissues. The technique requires the application of 80 - 120 seeds per patient. The implants of seeds have low impact and non-surgical procedures. Most patients can return to normal life within three days with little or no pain. This work proposes an alternative to the seeds that have already been developed, in order to reduce the cost by obtaining a better efficiency on fixing the radioactive iodine onto the epoxy resin. Methods have been developed to perform the fixation of Iodine-125 onto polymeric substrates. The parameters analyzed were the immersion time, type of static or dynamic reaction, concentration of the adsorption solution, the specific activity of the radioactive source, the need for carrier and chemical form of the radioactive Iodine. These experiments defined the most effective method to fixate the Iodine onto the polymeric material (epoxy resin), the Iodine activity in the polymeric substrate, the activity of the distribution of variation in a plot of polymeric cores and the efficiency of the epoxy resin to seal the seed. (author)

  20. Sorption and speciation of iodine in groundwater system: The roles of organic matter and organic-mineral complexes

    Science.gov (United States)

    Li, Junxia; Zhou, Hailing; Wang, Yanxin; Xie, Xianjun; Qian, Kun

    2017-06-01

    Characterizing the properties of main host of iodine in soil/sediment and the geochemical behaviors of iodine species are critical to understand the mechanisms of iodine mobilization in groundwater systems. Four surface soil and six subsurface sediment samples were collected from the iodine-affected area of Datong basin in northern China to conduct batch experiments and to evaluate the effects of NOM and/or organic-mineral complexes on iodide/iodate geochemical behaviors. The results showed that both iodine contents and kf-iodate values had positive correlations with solid TOC contents, implying the potential host of NOM for iodine in soil/sediment samples. The results of chemical removal of easily extracted NOM indicated that the NOM of surface soils is mainly composed of surface embedded organic matter, while sediment NOM mainly occurs in the form of organic-mineral complexes. After the removal of surface sorbed NOM, the decrease in kf-iodate value of treated surface soils indicates that surface sorbed NOM enhances iodate adsorption onto surface soil. By contrast, kf-iodate value increases in several H2O2-treated sediment samples, which was considered to result from exposed rod-like minerals rich in Fe/Al oxyhydroxide/oxides. After chemical removal of organic-mineral complexes, the lowest kf-iodate value for both treated surface soils and sediments suggests the dominant role of organic-mineral complexes on controlling the iodate geochemical behavior. In comparison with iodate, iodide exhibited lower affinities on all (un)treated soil/sediment samples. The understanding of different geochemical behaviors of iodine species helps to explain the occurrence of high iodine groundwater with iodate and iodide as the main species in shallow (oxidizing conditions) and deep (reducing conditions) groundwater.

  1. Sorption and speciation of iodine in groundwater system: The roles of organic matter and organic-mineral complexes.

    Science.gov (United States)

    Li, Junxia; Zhou, Hailing; Wang, Yanxin; Xie, Xianjun; Qian, Kun

    2017-06-01

    Characterizing the properties of main host of iodine in soil/sediment and the geochemical behaviors of iodine species are critical to understand the mechanisms of iodine mobilization in groundwater systems. Four surface soil and six subsurface sediment samples were collected from the iodine-affected area of Datong basin in northern China to conduct batch experiments and to evaluate the effects of NOM and/or organic-mineral complexes on iodide/iodate geochemical behaviors. The results showed that both iodine contents and k f -iodate values had positive correlations with solid TOC contents, implying the potential host of NOM for iodine in soil/sediment samples. The results of chemical removal of easily extracted NOM indicated that the NOM of surface soils is mainly composed of surface embedded organic matter, while sediment NOM mainly occurs in the form of organic-mineral complexes. After the removal of surface sorbed NOM, the decrease in k f -iodate value of treated surface soils indicates that surface sorbed NOM enhances iodate adsorption onto surface soil. By contrast, k f -iodate value increases in several H 2 O 2 -treated sediment samples, which was considered to result from exposed rod-like minerals rich in Fe/Al oxyhydroxide/oxides. After chemical removal of organic-mineral complexes, the lowest k f -iodate value for both treated surface soils and sediments suggests the dominant role of organic-mineral complexes on controlling the iodate geochemical behavior. In comparison with iodate, iodide exhibited lower affinities on all (un)treated soil/sediment samples. The understanding of different geochemical behaviors of iodine species helps to explain the occurrence of high iodine groundwater with iodate and iodide as the main species in shallow (oxidizing conditions) and deep (reducing conditions) groundwater. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Altering iodine metabolism in the calf by feeding iodine-binding agents

    International Nuclear Information System (INIS)

    Miller, J.K.; Swanson, E.W.; Lyke, W.A.; Byrne, W.F.

    1975-01-01

    Effects of feeding cottonseed meal and anion-exchange resin on iodine absorption and excretion by calves were investigated. Each additional amount of resin fed from 0.3 to 3.5 g/kg body weight further increased fecal excretion from single oral iodine-131 and intravenous iodine-125 doses. By feeding 3 to 10 g cottonseed meal/kg body weight, excretion of oral iodine-131 given daily was increased 7 to 94 percent in feces and reduced as much as 35 percent in urine, but plasma iodine-131 was not changed. Introducing 1 g resin/kg body weight daily into the diet increased fecal iodine-131 excretion three to five times that with cottonseed meal alone and reduced both plasma and urinary iodine-131. The same amount of resin fed daily had similar effects on excretion of iodine-131 injected subcutaneously each day. Although iodine depletion by a highly efficient iodine binder (resin) in the gastrointestinal tract is probable, iodine binding by a natural feed constituent (cottonseed meal) was relatively inefficient. (U.S.)

  3. Altering iodine metabolism in the calf by feeding iodine-binding agents

    International Nuclear Information System (INIS)

    Miller, J.K.; Swanson, E.W.; Lyke, W.A.; Byrne, W.F.

    1975-01-01

    Effects of feeding cottonseed meal and anion-exchange resin on iodine absorption and excretion by calves were investigated. Each additional amount of resin fed from 0.3 to 3.5 g/kg body weight further increased fecal excretion from single oral iodine-131 and intravenous iodine-125 doses. By feeding 3 to 10 g cottonseed meal/kg body weight, excretion of oral iodine-131 given daily was increased 7 to 94 percent in feces and reduced as much as 35 percent in urine, but plasma iodine-131 was not changed. Introducing 1 g resin/kg body weight daily into the diet increased fecal iodine-131 excretion three to five times that with cottonseed meal alone and reduced both plasma and urinary iodine-131. The same amount of resin fed daily had similar effects on excretion of iodine-131 injected subcutaneously each day. Although iodine depletion by a highly efficient iodine binder (resin) in the gastrointestinal tract is probable, iodine binding by a natural feed constituent (cottonseed meal) was relatively inefficient. (auth)

  4. Experimental study on iodine chemistry (EXSI) - Containment experiments with elemental iodine

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-10-15

    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. Oxidation of iodine in gas phase has been one of the greatest remaining uncertainties in iodine behaviour during a severe accident. In this study the possible formation of iodine oxide aerosol due to radiolytic oxidation of gaseous iodine is experimentally tested and the reaction products are analysed. The experimental facility applied in this study is based on the sampling system built at VTT for ISTP program project CHIP conducted 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. The results from the experiments show an extensive particle formation when ozone and gaseous iodine react with each other. The formed particles were collected on filters, while gaseous iodine was trapped into bubbles. The particles were iodine oxides and the size of particles was approximately 100 nm. The transport of gaseous iodine through the facility decreased when both gaseous iodine and ozone were fed together into facility. Experimental study on radiolytic oxidation of iodine was conducted in co-operation between VTT and Chalmers University of Technology as a part of the NKS-R programs. (author)

  5. Methanol Adsorption on Graphene

    Directory of Open Access Journals (Sweden)

    Elsebeth Schröder

    2013-01-01

    bonds like the covalent and hydrogen bonds. The adsorption of a single methanol molecule and small methanol clusters on graphene is studied at various coverages. Adsorption in clusters or at high coverages (less than a monolayer is found to be preferable, with the methanol C-O axis approximately parallel to the plane of graphene. The adsorption energies calculated with vdW-DF are compared with previous DFT-D and MP2-based calculations for single methanol adsorption on flakes of graphene (polycyclic aromatic hydrocarbons. For the high coverage adsorption energies, we also find reasonably good agreement with previous desorption measurements.

  6. [Dissociative identity disorder or schizophrenia?].

    Science.gov (United States)

    Tschöke, S; Steinert, T

    2010-01-01

    We present a case of dissociative identity disorder in which Schneiderian first rank symptoms were present besides of various states of consciousness. Thus the diagnosis of schizophrenia had to be considered. Formally, the symptoms met ICD-10 criteria for schizophrenia. However, taking into account the lack of formal thought disorder and of negative symptoms as well as a typical history of severe and prolonged traumatisation, we did not diagnose a co-morbid schizophrenic disorder. There is good evidence for the existence of psychotic symptoms among patients with dissociative disorders. However, in clinical practice this differential diagnosis is rarely considered.

  7. Iodine deficiency disorders in Sarawak, Malaysia.

    Science.gov (United States)

    Kiyu, A; Tambi, Z; Ahmad, Y

    1998-12-01

    The state of Sarawak in Malaysia has a high prevalence of iodine deficiency disorders (IDD). This has been revealed through a review of goitre surveys that were carried out in the State from the early 1970s to the 1990s. The primary cause was low iodine intake. Contributory factors were low iodine content in the soil and water as well as high cassava consumption. Virtual elimination of IDD is one of the nutritional goals of the IDD prevention and control programs. The strategies adopted include the iodination of coarse salt, which is sold in the market by shopkeepers and also provided free from government health clinics; legislation requiring that salt sold in IDD-gazetted areas must be iodised; and the use of iodinators to iodise water supplied by the gravity-feed system to villages and boarding schools in rural areas. The indicators used in the monitoring and evaluation of the program include the availability of iodised salt in the market and households, iodine levels in water supply that had been fitted with iodinators, goitre volume measured by ultrasound, and urinary iodine excretion among school children.

  8. High coverage hydrogen adsorption on the Fe{sub 3}O{sub 4}(1 1 0) surface

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Xiaohu, E-mail: yuxiaohu950203@126.com [College of Physics and Electrical Engineering, Anyang Normal University, Anyang, Henan 455000 (China); State Key laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi 030001 (China); Zhang, Xuemei [College of Physics and Electrical Engineering, Anyang Normal University, Anyang, Henan 455000 (China); Wang, Shengguang [State Key laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi 030001 (China); Synfuels China Co., Ltd., Huairou, Beijing 101407 (China)

    2015-10-30

    Graphical abstract: - Highlights: • Hydrogen adsorption on the A and B termination layers of the Fe{sub 3}O{sub 4}(1 1 0) surface at different coverage has been studied by DFT + U method. • The adsorption of hydrogen prefers surface oxygen atoms on both Fe{sub 3}O{sub 4}(1 1 0) surface layers. • The more stable A layer has stronger adsorption energy than the less stable B layer. • The saturation coverage has two dissociatively adsorbed H{sub 2} on the A layer, and one dissociatively adsorbed H{sub 2} on the B layer. - Abstract: Hydrogen adsorption on the A and B termination layers of the Fe{sub 3}O{sub 4}(1 1 0) surface at different coverage has been systematically studied by density functional theory calculations including an on-site Hubbard term (GGA + U). The adsorption of hydrogen prefers surface oxygen atoms on both layers. The more stable A layer has stronger adsorption energy than the less stable B layer. The saturation coverage has two dissociatively adsorbed H{sub 2} on the A layer, and one dissociatively adsorbed H{sub 2} on the B layer. The adsorption mechanism has been analyzed on the basis of projected density of states (PDOS).

  9. Dissociative symptoms and dissociative disorders comorbidity in obsessive compulsive disorder: Symptom screening, diagnostic tools and reflections on treatment

    OpenAIRE

    Belli, Hasan

    2014-01-01

    Borderline personality disorder, conversion disorder and obsessive compulsive disorder frequently have dissociative symptoms. The literature has demonstrated that the level of dissociation might be correlated with the severity of obsessive compulsive disorder (OCD) and that those not responding to treatment had high dissociative symptoms. The structured clinical interview for DSM-IV dissociative disorders, dissociation questionnaire, somatoform dissociation questionnaire and dissociative expe...

  10. Treatment of hyperthyroidism with radioactive iodine

    International Nuclear Information System (INIS)

    Bell, R.L.

    1974-01-01

    While radioactive iodine is clearly the therapy of choice for Graves' disease (even in younger patients) the use of radioactive iodine for therapy of the toxic multinodular or uninodular goiter presents an entirely different problem. Although these two entities can be treated with radioactive iodine provided there is some suppression of the tissue that is not autonomous, transient release of thyroid hormone may induce symptoms of thyroid storm in the very large multinodular toxic goiter treated with radioiodine therapy. These toxic nodules generally require much larger doses of radioiodine than is commonly used for classical Graves' disease and may either require fractional administration of radioisotopes or concomitant use of antithyroid drugs and iodides. In general, surgery remains the treatment of choice for large toxic multinodular goiters, after proper preparation by medical means including radioactive iodine. Radioactive iodine therapy for hyperthyroidism is contraindicated in pregnancy and generally is not used in children below five years of age. (U.S.)

  11. Iodine in eggs in an iodopenic region

    International Nuclear Information System (INIS)

    Bogdanov, Bogdan; Gonev, Mihail; Tadzher, Isak S.

    1996-01-01

    Macedonia is a region with a recognized precarious iodine balance, due to iodine deficiency in almost all water sources. Five percent iodine intake through eggs in the daily diet of adults is significant in this balance. The content of 40-220 micro g I - /kg eggs is lower than the British one (average 340-370 micro g I - /kg). The amount per egg is 3-6 micro g I' far less than 711 micro g I - in special iodine-enriched eggs designed for treatment of thyroid and metabolic disorders by feeding chickens with kelp additives. The iodine content of our manufacturers, provides substantial part of former Yugoslavia with eggs, is entirely dependent on imported fishmeal in chicken feed. (Author)

  12. Radioiodination of methoxsalen using different iodinating agents

    International Nuclear Information System (INIS)

    Ayyoub, S.M.; Farah, K.

    2007-01-01

    Different iodinating agents such as chloramine-T (Ch-T), iodogen, H 2 O 2 and N-bromosuccinimide (NBS) were used for the labelling of methoxsalen via electrophilic substitution reaction. These iodinating agents oxidize NaI to produce the iodonium ions which attacked the active position in methoxsalen. These iodinating agents successfully iodinate the methoxsalen with a reasonable radiochemical yield and purity. The factors affecting both chemical yield and purity, such as the concentration of the iodinating agent, the methoxsalen concentration and the reaction time, were studied. Different developing solvents were used for the identification of the products using TLC technique. It was found that the most suitable solvent for the identification of methoxsalen using TLC was n-butanol : acetic acid : water (4:1:1). Radiochemical yields of 80% and 84% , with purity 99%, were achieved in case of NBS and H 2 O 2 , respectively

  13. Methodology for iodine-129 determination in coniferous plant by neutron activation

    International Nuclear Information System (INIS)

    Quintana, E.E.; Thyssen, S.M.

    1998-01-01

    Full text: The measurement methods of iodine-129 ( 129 I) include liquid scintillation counting, mass spectrometry analysis, X-ray spectrometry and neutron activation analysis. The combination of long half-life and low radiation energy, limit the sensitivity of a direct measurement in environmental matrixes. The neutron activation analysis (NAA) permits the increase in the sensitivity because of the high thermal neutron cross section of 129 I. The reaction produced is 129 I (n,γ) 130 I and the Eγ (536 keV) of iodine-130 (t 1/2 = 12,6 hours) is measured. The developed methodology allows the determination of 129 I in coniferous needles using NAA. The chemical treatment removes the interferences present in the matrix, as well as the Bromine-82 originated in the activation process. The analytical method is divided in six steps: a) digestion by alkaline fusion; b) radiochemical purification of 129 I by distillation followed by solvent extraction; c) distillation and adsorption on activated charcoal; d) neutron irradiation; e) radiochemical purification of 130 I by distillation followed by solvent extraction; f) gamma spectrometry. Iodine-131 tracer is added, and a chemical recovery of 95% in the distillations is obtained. The whole process recovery is within 70% and 85%. The detection limit is 0.48 mBq. Several factors affect this value, such as sample type, variety of coniferous, natural iodine concentration, irradiation time and neutron flux. (author) [es

  14. Overview of the ACEX project iodine work

    Energy Technology Data Exchange (ETDEWEB)

    Merilo, M.

    1996-12-01

    The ACEX project is an internationally sponsored research program that focuses on several aspects of severe accidents. The areas addressed are iodine behavior in containments, pool scrubbing, molten corium concrete interactions, and ex-vessel core debris coolability. These areas all represent extensions to the previous and current ACE and MACE programs respectively. The ACE-Phase B (iodine) project, and other recent research efforts, have clarified the roles of the important phenomena that influence iodine volatility in reactor containments during severe accidents. The ACE Iodine Chemistry Subcommittee concluded that even though enough data has been generated to support reasonably good quantification of the important phenomena, a few important areas remain where quantification is still uncertain. This is due to a lack of agreement on how to utilize the existing database, as well as the possible absence of critical test and/or property data. Technical resolution of the overall iodine behavior issue is therefore not feasible until these uncertainties are fully assessed and practical solutions have been identified, implemented, and verified. The overall objectives of the ACEX iodine research program are to ensure that the iodine database can be used to predict the airborne concentration of iodine, the conditions for iodine reservoir stability, and to provide a mechanistic understanding for these phenomena. The first phase of this work involves a comprehensive review and interpretation of the existing database in order to formulate practical strategies for dealing with significant uncertainties and/or deficiencies. Several projects are underway involving the effects of organic reactions and structural surface interactions. In addition effort is being expended on standardizing the aqueous iodine kinetics database, specifying useful mass transfer models, and defining methodology for pH prediction. (Abstract Truncated)

  15. Content iodine in sauces of type emulsion

    Directory of Open Access Journals (Sweden)

    M. Bakirov

    2015-05-01

    Full Text Available Introduction. The scarcity of natural resources arouse a necessity to find additional sources of protein, fat, carbohydrates, and their complexes with scarce mineral compounds. Therefore, a relevant issue is to enrich the diets deficient iodine compounds through research and development of new food products. Materials and methods. Investigation of iodine content in emulsion-type sauces at all stages was performed using Xray -fluorescence analyzer «Elvax». X-ray -fluorescence method consists of the appearance characteristic X-radiation of atoms of a chemical element at infringement they the primary X-ray irradiation. Results and discussion. Investigated for the determination of organic and inorganic forms of iodine in content of food items, and installed the total loss of iodine in sauces after cooking and storage at +5 ... +10 ° C for 30 days. Using iodine-proteinaceous additive from 0.5 ... 2.5% by mass of iodine 0.01% can be achieved from 15 to 50% of the human daily requirement by iodine. The resulting product does not lose its organoleptic, physico - chemical, consumer characteristics and meets the requirements of normative documents. As a result of our research, it was found that the addition of the supplements enriched protein-mineral (SEPM in composition sauces does not adversely affect the physical -chemical characteristics of sauces, but due to the stabilizing effect of additives iodine-proteinaceous increased emulsion stability up to 98 - 100% without additional foo d additives (emulsifiers. This additive has passed a series of tests that indicate on compliance with requirements normative and technical documentation. Conclusions. Used methodical approach allowed us to estimate the level of organic and inorganic iodine, as well as describe in more detail and correctly interpret the chemical composition of foods fortified with iodine and predict their health properties.

  16. Dietary iodine intake in the Chinese population.

    Science.gov (United States)

    Sui, Hai Xia; Li, Jian Wen; Mao, Wei Feng; Zhu, Jiang Hui; He, Yu Na; Song, Xiao Yu; Ma, Ning; Zhang, Lei; Liu, Sa Na; Liu, Zhao Ping; Li, Feng Qin

    2011-12-01

    To evaluate dietary iodine intake and its potential risks among the Chinese population. Individual dietary iodine intake was calculated using food consumption data multiplying by iodine concentration in foods, table salt and drinking water, followed by summing, and then compared with the corresponding age-specific reference values, including Upper Intake Level (UL) and Recommended Nutrient Intake (RNI). In areas with water iodine concentration (WI) lower than 150 μg/L, 80.8% of residents had iodine intake between the RNI and UL, 5.8% higher than UL, and the remaining (13.4%) lower than RNI if iodized salt was consumed. However, in the uniodized salt consumption scenario, only 1.0% of residents between RNI and UL, 1.4% higher than UL, and a large part of residents (97.6%) lower than RNI. In areas with WI higher than 150 μg/L, all residents had iodine intake between RNI and UL if iodized salt was consumed, except 10.5% and 24.9% of residents higher than UL in areas with WI at 150-300 μg/L and higher than 300 μg/L respectively. However, in the uniodized salt consumption scenario, only 1.5% and 1.7% of residents had higher iodine intake than UL respectively. The findings suggested that in general, the dietary iodine intake by the Chinese population was appropriate and safe at the present stage. People in areas with WI lower than 150 μg/L were more likely to have iodine deficiency. While people in areas with WI higher than 150 μg/L were more likely to have excessive iodine intake if iodized salt was consumed. Copyright © 2011 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.

  17. Hydrogen dissociation on metal surfaces

    NARCIS (Netherlands)

    Wijzenbroek, M.

    2016-01-01

    Dissociative chemisorption is an important reaction step in many catalytic reactions. An example of such a reaction is the Haber-Bosch process, which is used commercially to produce ammonia, an important starting material in the production of fertilisers. In theoretical descriptions of such chemical

  18. DISSOCIATIVE DISORDERS IN DSM-5

    NARCIS (Netherlands)

    Spiegel, David; Loewenstein, Richard J.; Lewis-Fernandez, Roberto; Sar, Vedat; Simeon, Daphne; Vermetten, Eric; Cardena, Etzel; Dell, Paul F.

    Background: We present recommendations for revision of the diagnostic criteria for the Dissociative Disorders (DDs) for DSM-5. The periodic revision of the DSM provides an opportunity to revisit the assumptions underlying specific diagnoses and the empirical support, or lack of it, for the defining

  19. Modelfree determination of dissociation energies

    International Nuclear Information System (INIS)

    Vogel, M.; Herlert, A.; Hansen, K.; Schweikhard, L.

    2002-01-01

    The most fundamental parameter in the characterization of any free stable polyatomic particle (molecule, fullerene, polymer or cluster) is its dissociation energy, which reflects structural and dynamical properties of the system under investigation. A new method to determine the dissociation energy (DE) is presented. It allows a DE direct measurement without any assumptions on how the disintegration process proceeds, does not relay on any model of the system, or other properties. Its basic idea is to compare the excitation energy E A of a sequential decay ( A-->B-->C) with the corresponding energy E B of the single decay (B-->C) that leads to the final product. When the single decay process depends in a measurable way on the amount of excitation energy present, it can be used as an uncalibrated thermometer for the last step of the sequential reaction. Adjusting either of the two excitation energies E A and E B to produce the same reading of the thermometer, the difference in excitation energies, E A - E B , is a direct measure of the energy consumed in the first step of the sequential decay, thus is the dissociation energy of A. As an example, dissociation energies of a series of gold clusters Au n + (n=14-24) were determined. (nevyjel)

  20. Energy localization and molecular dissociation

    International Nuclear Information System (INIS)

    Takeno, S.; Tsironis, G.P.

    2005-01-01

    We study analytically as well as numerically the role that large-amplitude vibrations play during the process of molecular dissociation. Our model consists of a linear three-atom molecule composed of identical atoms interacting with their nearest neighbors by Morse potentials. We find a close relation between energy localization and bond breaking and evaluate numerically the corresponding reaction paths

  1. Low-level seaweed supplementation improves iodine status in iodine-insufficient women.

    Science.gov (United States)

    Combet, Emilie; Ma, Zheng Feei; Cousins, Frances; Thompson, Brett; Lean, Michael E J

    2014-09-14

    Iodine insufficiency is now a prominent issue in the UK and other European countries due to low intakes of dairy products and seafood (especially where iodine fortification is not in place). In the present study, we tested a commercially available encapsulated edible seaweed (Napiers Hebridean Seagreens® Ascophyllum nodosum species) for its acceptability to consumers and iodine bioavailability and investigated the impact of a 2-week daily seaweed supplementation on iodine concentrations and thyroid function. Healthy non-pregnant women of childbearing age, self-reporting low dairy product and seafood consumption, with no history of thyroid or gastrointestinal disease were recruited. Seaweed iodine (712 μg, in 1 g seaweed) was modestly bioavailable at 33 (interquartile range (IQR) 28-46) % of the ingested iodine dose compared with 59 (IQR 46-74) % of iodine from the KI supplement (n 22). After supplement ingestion (2 weeks, 0·5 g seaweed daily, n 42), urinary iodine excretion increased from 78 (IQR 39-114) to 140 (IQR 103-195) μg/l (Pseaweed was palatable and acceptable to consumers as a whole food or as a food ingredient and effective as a source of iodine in an iodine-insufficient population. In conclusion, seaweed inclusion in staple foods would serve as an alternative to fortification of salt or other foods with KI.

  2. Mercury separation from concentrated potassium iodide/iodine leachate using Self-Assembled Mesoporous Mercaptan Support (SAMMS) technology

    International Nuclear Information System (INIS)

    Mattigod, S.V.; Feng, X.; Fryxell, G.E.

    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 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 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 ∼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 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 5 to >2.6x10 8 ml/g) indicated that material adsorbs Hg with very high specificity from KI/I 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 2 leachates confirmed the highly specific Hg adsorption properties (K d >6x10 7 to>1x10 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

  3. Dissociating Prediction Failure: Considerations from Music Perception

    DEFF Research Database (Denmark)

    Ross, Suzi; Hansen, Niels Christian

    2016-01-01

    Dissociating Prediction Failure: Considerations from Music Perception The Journal of Neuroscience, 16 March 2016, 36(11): 3103-3105;......Dissociating Prediction Failure: Considerations from Music Perception The Journal of Neuroscience, 16 March 2016, 36(11): 3103-3105;...

  4. A First Principles Study of H2 Adsorption on LaNiO3(001 Surfaces

    Directory of Open Access Journals (Sweden)

    Changchang Pan

    2017-01-01

    Full Text Available The adsorption of H2 on LaNiO3 was investigated using density functional theory (DFT calculations. The adsorption sites, adsorption energy, and electronic structure of LaNiO3(001/H2 systems were calculated and indicated through the calculated surface energy that the (001 surface was the most stable surface. By looking at optimized structure, adsorption energy and dissociation energy, we found that there were three types of adsorption on the surface. First, H2 molecules completely dissociate and then tend to bind with the O atoms, forming two –OH bonds. Second, H2 molecules partially dissociate with the H atoms bonding to the same O atom to form one H2O molecule. These two types are chemical adsorption modes; however, the physical adsorption of H2 molecules can also occur. When analyzing the electron structure of the H2O molecule formed by the partial dissociation of the H2 molecule and the surface O atom, we found that the interaction between H2O and the (001 surface was weaker, thus, H2O was easier to separate from the surface to create an O vacancy. On the (001 surface, a supercell was constructed to accurately study the most stable adsorption site. The results from analyses of the charge population; electron localization function; and density of the states indicated that the dissociated H and O atoms form a typical covalent bond and that the interaction between the H2 molecule and surface is mainly due to the overlap-hybridization among the H 1s, O 2s, and O 2p states. Therefore, the conductivity of LaNiO3(001/H2 is stronger after adsorption and furthermore, the conductivity of the LaNiO3 surface is better than that of the LaFeO3 surface.

  5. Efficient noble metal nanocatalysts supported on HfC(001 for O2 dissociation

    Directory of Open Access Journals (Sweden)

    Shiyan Wang

    2017-03-01

    Full Text Available The adsorption and dissociation of O2 on the M4 (M=Au, Pd, Pt clusters supported on HfC(001 (Hafnium Carbide are investigated using ab initio density functional theory calculations. The geometric and electronic structures are analyzed in detail. It is found that the dissociation barriers of O2 on Au4/HfC(001 (0.26 eV, Pd4/HfC(001 (0.49 eV and Pt4/HfC(001 (0.09 eV are much smaller than those on the clean surfaces of HfC(001 (1.60 eV, Au(111 (1.37 eV, Pd(111 (1.0 and 0.91 eV and Pt(111 (0.27–0.7 eV, respectively. The low dissociation barriers imply that the Pt4/HfC(001 exhibits the highest catalytic activity for O2 dissociation, and the Au4/HfC(001 and Pd4/HfC(001 may also be possible substitutes with lower cost for the current Pt/C catalyst for O2 dissociation. The present study is conductive to designing new efficient noble metal catalyst using HfC support for efficiently promoting O2 dissociation.

  6. Global functioning and disability in dissociative disorders.

    Science.gov (United States)

    Mueller-Pfeiffer, Christoph; Rufibach, Kaspar; Perron, Noelle; Wyss, Daniela; Kuenzler, Cornelia; Prezewowsky, Cornelia; Pitman, Roger K; Rufer, Michael

    2012-12-30

    Dissociative disorders are frequent comorbid conditions of other mental disorders. Yet, there is controversy about their clinical relevance, and little systematic research has been done on how they influence global functioning. Outpatients and day care patients (N=160) of several psychiatric units in Switzerland were assessed with the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV Axis I Disorders, Structured Clinical Interview for DSM-IV Dissociative Disorders, Global Assessment of Functioning Scale, and World Health Organization Disability Assessment Schedule-II. The association between subjects with a dissociative disorder (N=30) and functional impairment after accounting for non-dissociative axis I disorders was evaluated by linear regression models. We found a proportion of 18.8% dissociative disorders (dissociative amnesia=0%, dissociative fugue=0.6%, depersonalization disorder=4.4%, dissociative identity disorder=7.5%, dissociative disorder-not-otherwise-specified=6.3%) across treatment settings. Adjusted for other axis I disorders, subjects with a comorbid dissociative identity disorder or dissociative disorder-not-otherwise-specified had a median global assessment of functioning score that was 0.86 and 0.88 times, respectively, the score of subjects without a comorbid dissociative disorder. These findings support the hypothesis that complex dissociative disorders, i.e., dissociative identity disorder and dissociative disorder-not-otherwise-specified, contribute to functional impairment above and beyond the impact of co-existing non-dissociative axis I disorders, and that they qualify as "serious mental illness". Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  7. Effect of iodine supplementation in pregnant women on child neurodevelopment

    NARCIS (Netherlands)

    Gowachirapant, Sueppong; Jaiswal, Nidhi; Melse-Boonstra, Alida; Galetti, Valeria; Stinca, Sara; Mackenzie, Ian; Thomas, Susan; Thomas, Tinku; Winichagoon, Pattanee; Srinivasan, Krishnamachari; Zimmermann, Michael B.

    2017-01-01

    Background: Iodine deficiency during pregnancy might be associated with reduced intelligence quotient (IQ) score in offspring. We assessed the effect of iodine supplementation in mildly iodine-deficient pregnant women on neurodevelopment of their offspring in areas where schoolchildren were iodine

  8. Prevalence and serverity of Iodine deficiency disorder among ...

    African Journals Online (AJOL)

    The median urinary iodine level was 56 4g/L that indicates iodine deficiency. Out of 389 households in the study area, 277 (71.2%) were using non-iodinated salt, 102 (26.2%) of the households were using iodinated salt. Cabbage usage was significantly associated with goiter. CONCLUSION: Endemic goiter is quite ...

  9. Iodine Deficiency Disorders (IDD) in Burie and Womberma Districts ...

    African Journals Online (AJOL)

    Iodine deficiency disorders (IDD) affect millions of people in developing countries mainly due to dietary iodine deficiency and aggravating factors that affect the bioavailability of iodine in the body. Iodine deficiency disorder is one of the public health problems of Ethiopia. Recent findings show that both endemic and ...

  10. Iodine deficiency in primary school children and knowledge of ...

    African Journals Online (AJOL)

    Background: More than two billion individuals worldwide have inadequate iodine intake and the adverse consequences of iodine deficiency are widely observed. Objective: To assess the iodine status of primary school children and the knowledge of iodine deficiency disorders among their caretakers. Methods: A ...

  11. Interfacial adsorption of insulin - Conformational changes and reversibility of adsorption

    NARCIS (Netherlands)

    Mollmann, SH; Jorgensen, L; Bukrinsky, JT; Elofsson, U; Norde, W; Frokjaer, S

    The adsorption of human insulin to Teflon particles was studied with respect to conformational changes and the reversibility of adsorption was examined by total internal reflection fluorescence (TIRF). Adsorption isotherms for the adsorption of human insulin indicated high affinity adsorption, even

  12. Interfacial adsorption of insulin. Conformational changes and reversibility of adsorption

    NARCIS (Netherlands)

    Mollmann, S.H.; Bukrinsky, J.T.; Elofsson, U.; Norde, W.; Frokjaer, S.

    2006-01-01

    The adsorption of human insulin to Teflon particles was studied with respect to conformational changes and the reversibility of adsorption was examined by total internal reflection fluorescence (TIRF). Adsorption isotherms for the adsorption of human insulin indicated high affinity adsorption, even

  13. Active molecular iodine photochemistry in the Arctic

    Science.gov (United States)

    Raso, Angela R. W.; Custard, Kyle D.; May, Nathaniel W.; Tanner, David; Newburn, Matt K.; Walker, Lawrence; Moore, Ronald J.; Huey, L. G.; Alexander, Liz; Shepson, Paul B.; Pratt, Kerri A.

    2017-09-01

    During springtime, the Arctic atmospheric boundary layer undergoes frequent rapid depletions in ozone and gaseous elemental mercury due to reactions with halogen atoms, influencing atmospheric composition and pollutant fate. Although bromine chemistry has been shown to initiate ozone depletion events, and it has long been hypothesized that iodine chemistry may contribute, no previous measurements of molecular iodine (I2) have been reported in the Arctic. Iodine chemistry also contributes to atmospheric new particle formation and therefore cloud properties and radiative forcing. Here we present Arctic atmospheric I2 and snowpack iodide (I-) measurements, which were conducted near Utqiaġvik, AK, in February 2014. Using chemical ionization mass spectrometry, I2 was observed in the atmosphere at mole ratios of 0.3-1.0 ppt, and in the snowpack interstitial air at mole ratios up to 22 ppt under natural sunlit conditions and up to 35 ppt when the snowpack surface was artificially irradiated, suggesting a photochemical production mechanism. Further, snow meltwater I- measurements showed enrichments of up to ˜1,900 times above the seawater ratio of I-/Na+, consistent with iodine activation and recycling. Modeling shows that observed I2 levels are able to significantly increase ozone depletion rates, while also producing iodine monoxide (IO) at levels recently observed in the Arctic. These results emphasize the significance of iodine chemistry and the role of snowpack photochemistry in Arctic atmospheric composition, and imply that I2 is likely a dominant source of iodine atoms in the Arctic.

  14. Iodine nutrition and risk of thyroid irradiation from nuclear accidents

    International Nuclear Information System (INIS)

    Delange, F.

    1990-01-01

    The objectives of this paper are to discuss the following aspects of physiopathology of iodine nutrition related to thyroid irradiation by nuclear accidents: (1) The cycle of iodine in nature, the dietary sources of iodine and the recommended dietary allowances for iodine. (2) The anomalies of thyroid metabolism induced by iodine deficiency. The caricatural situation as seen in endemic goitre will be used as mode. (3) The specific paediatric aspects of adaptation to iodine deficiency. (4) The present status of iodine nutrition in Europe. (author)

  15. Present status of iodine research at IPSN

    Energy Technology Data Exchange (ETDEWEB)

    Bardelay, J. [IPSN/DPEA/SEAC (France)

    1996-12-01

    Since several years, IPSN has conducted an effort in order to evaluate the release of radioactive iodine in case of hypothetical severe accident in a realistic manner. This source-term evaluation is performed with IODE code which is a module of the EXCADRE system of codes. This code is validated against: -analytical experiments: in these experiments, IPSN studies radiolytic effects and chemical processes in the sump, organic formation, mass transfer, effect of spray (CARAIDAS experiment), - the CAIMAN semi global experiment; this experiment will allow to study the phenomena linked to iodine behavior under representative containment geometry in the presence of painted surfaces and global irradiation, - the PHEBUS FP program. The paper consists to describe succinctly the current status of IODE and the various experiments for its validation. In case of hypothetical severe accident iodine can induce important perturbations of human organism. The effects are principally radiological, in particular on the thyroid. At short term, radioactive iodine is the most important contributor for the sanitary risk. It represents 55% of effective dose and 92% of thyroid dose at 10 km in case of controlled rejects with current assumptions. This is the reason why it must be actively studied. In France, the safety evaluations are performed with mechanistic codes or lumped parameter codes like EXCADRE which contains a module devoted to iodine studies: IODINE. The objective of the French experimental program on iodine is to understand and quantify important phenomena in order to put kinetic parameters in IODE module. The experiments can be classified in analytical experiments, the semi-global experiment CAIMAN which takes into account different phenomena studied in analytical experiments and the global experiment PHEBUS PF, not only devoted to iodine behavior study. In the following text we will present the needs of IODINE code and these different experiments. (author).

  16. Present status of iodine research at IPSN

    International Nuclear Information System (INIS)

    Bardelay, J.

    1996-01-01

    Since several years, IPSN has conducted an effort in order to evaluate the release of radioactive iodine in case of hypothetical severe accident in a realistic manner. This source-term evaluation is performed with IODE code which is a module of the EXCADRE system of codes. This code is validated against: -analytical experiments: in these experiments, IPSN studies radiolytic effects and chemical processes in the sump, organic formation, mass transfer, effect of spray (CARAIDAS experiment), - the CAIMAN semi global experiment; this experiment will allow to study the phenomena linked to iodine behavior under representative containment geometry in the presence of painted surfaces and global irradiation, - the PHEBUS FP program. The paper consists to describe succinctly the current status of IODE and the various experiments for its validation. In case of hypothetical severe accident iodine can induce important perturbations of human organism. The effects are principally radiological, in particular on the thyroid. At short term, radioactive iodine is the most important contributor for the sanitary risk. It represents 55% of effective dose and 92% of thyroid dose at 10 km in case of controlled rejects with current assumptions. This is the reason why it must be actively studied. In France, the safety evaluations are performed with mechanistic codes or lumped parameter codes like EXCADRE which contains a module devoted to iodine studies: IODINE. The objective of the French experimental program on iodine is to understand and quantify important phenomena in order to put kinetic parameters in IODE module. The experiments can be classified in analytical experiments, the semi-global experiment CAIMAN which takes into account different phenomena studied in analytical experiments and the global experiment PHEBUS PF, not only devoted to iodine behavior study. In the following text we will present the needs of IODINE code and these different experiments. (author)

  17. Study on iodine levels in thyroids of iodine-supplemented rats by epithermal neutron activation analysis

    International Nuclear Information System (INIS)

    Wang Xuefei; Zhang Fang; Xu Qing; Liu Nianqing; Chai Zhifang; Zhao Xueqin; Zuo Aijun

    2003-01-01

    The second generation female Wistar rats that have been treated with iodine-deficient food, after their delivery, are divided into three groups i.e. excessive-iodine (EI), adequate-iodine (AI) and iodine-deficient (ID) according to the KIO 3 concentration in the drinking water (3.0, 0.4, 0 mg/L). In addition, the normal rats with low iodine food and 0.4 mg/L KIO 3 water are used as the control group (C). The iodine content in thyroid and the serum thyroid hormone levels of the third generation rats are measured by means of epithermal neutron activation analysis (ENAA), and the method of enzyme-linked immunosorbent assay (ELISA), respectively. The results indicate that the total thyroxine (TT 4 ) and the free thyroxine (FT 4 ) of the EI, compared with those of the controls, are significantly decreased (p 3 ) evidently increased (p 4 , FT 4 and goiter

  18. Modeling an Iodine Hall Thruster Plume in the Iodine Satellite (ISAT)

    Science.gov (United States)

    Choi, Maria

    2016-01-01

    An iodine-operated 200-W Hall thruster plume has been simulated using a hybrid-PIC model to predict the spacecraft surface-plume interaction for spacecraft integration purposes. For validation of the model, the plasma potential, electron temperature, ion current flux, and ion number density of xenon propellant were compared with available measurement data at the nominal operating condition. To simulate iodine plasma, various collision cross sections were found and used in the model. While time-varying atomic iodine species (i.e., I, I+, I2+) information is provided by HPHall simulation at the discharge channel exit, the molecular iodine species (i.e., I2, I2+) are introduced as Maxwellian particles at the channel exit. Simulation results show that xenon and iodine plasma plumes appear to be very similar under the assumptions of the model. Assuming a sticking coefficient of unity, iodine deposition rate is estimated.

  19. Effect of chronic douching with polyvinylpyrrolidone-iodine on iodine absorption and thyroid function

    International Nuclear Information System (INIS)

    Safran, M.; Braverman, L.E.

    1982-01-01

    Daily vaginal douching with polyvinylpyrrolidone-iodine in 12 euthyroid volunteers for 14 days resulted in a significant increase in serum total iodine concentration and urine iodine excretion. The increase in serum total iodine was associated with a marked decrease in 24-hour 123 I uptake by the thyroid and a small but significant increase in serum thyrotropin (TSH) concentration. However, values for serum TSH never rose above the normal range. No significant changes in serum thyroxine (T4), free T4 index (FTI), or triiodothyronine concentrations were observed, although serum T4 and FTI did decrease slightly during treatment. The findings suggest that iodine is absorbed across the vaginal mucosa and that the subsequent increase in serum total iodine does induce subtle increases in serum TSH concentration. There was no evidence, however, of overt hypothyroidism in these euthyroid women

  20. Adsorption of nitrogen on potassium promoted Fe(111) and (100) surfaces

    Science.gov (United States)

    Ertl, G.; Lee, S. B.; Weiss, M.

    1982-02-01

    Dissociative nitrogen adsorption through N2 ⇌ N2, ad → 2 Ns is the rate limiting step in ammonia synthesis over iron catalysts. This model study deals with the "promoter" action of potassium by studying the influence of preadsorbed K on the energetics and kinetics of molecular and atomic nitrogen adsorption on Fe(111) and Fe(100). The heat of adsorption of molecular nitrogen is locally increased to about 11 kcal/mole in the vicinity of an adsorbed K atom, which phenomenon simultaneously lowers the activation barrier for dissociation. As a consequence the effective sticking coefficient for dissociative nitrogen adsorption is markedly increased. This effect is less pronounced for Fe(111) than for Fe(100) so that the difference in activity observed with the K-free surfaces is eliminated. The increase of the N 2 adsorption energy is attributed to the enhanced electron density of the substrate (due to charge transfer from K) which enables a more pronounced "backbonding" contribution to the adsorption bond.

  1. Iodine excretion has decreased in Denmark between 2004 and 2010 - the importance of iodine content in milk

    DEFF Research Database (Denmark)

    Rasmussen, Lone Banke; Carlé, Allan; Jørgensen, Torben

    2014-01-01

    Fortification with the essential trace element iodine is widespread worldwide. In the present study, results on iodine excretion and intake of iodine-rich foods from a cross-sectional study carried out in 2004-5, 4 to 5 years after the implementation of mandatory iodine fortification, were compar...

  2. From dissociation to trauma? Individual differences in dissociation as predictor of 'trauma' perception.

    Science.gov (United States)

    Rassin, Eric; van Rootselaar, Anne-Fleur

    2006-06-01

    In clinical literature, dissociative complaints are generally considered to be the result of traumatic experiences. However, it has been argued that dissociative complaints, in turn, may indulge over-reporting of traumatic experiences. Hence, correlations between dissociation and self-reported trauma may not only reflect the causal path from trauma to dissociation, but possibly also an increased trauma-item endorsement due to dissociation. To test the idea that dissociation fosters a positive response bias on trauma self-reports, participants completed a dissociation scale, and subsequently rated the perceived trauma of ambiguous stimuli. Results indicated that some dissociative complaints indeed predicted increased scores on the trauma ratings, while other manifestations of dissociation were negatively correlated with perceived trauma ratings. Hence, there is reason to argue that people differ in their readiness to perceive a situation as traumatic. However, the association between self-reported dissociation and the perception of 'trauma' is not quite clear-cut.

  3. Effect of transition metal-doped Ni(211) for CO dissociation: Insights from DFT calculations

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Kuiwei; Zhang, Minhua [Key Laboratory for Green Chemical Technology of Ministry of Education, R& D Center for Petrochemical Technology, Tianjin University, Tianjin 300072 (China); Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072 (China); Yu, Yingzhe, E-mail: yzhyu@tju.edu.cn [Key Laboratory for Green Chemical Technology of Ministry of Education, R& D Center for Petrochemical Technology, Tianjin University, Tianjin 300072 (China)

    2017-03-31

    Highlights: • Doping the step edge of Ni(211) with Fe or Ru observably enhances CO dissociation. • Rh doping is unfavorable for CO activation both kinetically and thermodynamically. • Two neat linear relations are proposed besides the Brønsted–Evans–Polanyi relation. • The differences of CO adsorption are rationalized via the Blyholder model. - Abstract: Density functional theory slab calculations were performed to investigate the adsorption and dissociation of CO over pure and M-doped Ni(211) (M = Fe, Co, Ru and Rh) with the aim to elucidate the effect of transition metal doping for CO activation. Doping the step edge of Ni(211) with Fe, Co and Ru is found to enhance the binding of CO in the initial state (IS) (in the sequence by the improvement degree: Fe > Ru > Co) as well as the co-adsorption of C and O in the final state (FS) (Ru > Fe > Co). In contrast, Rh doping is unfavorable both in the IS and in the FS. Analysis of the overall potential energy surfaces (PES) suggests CO dissociation is facilitated by Fe, Ru and Co doping both kinetically and thermodynamically, wherein Fe and Ru behave extraordinary. Interestingly, Fe substitute is slightly superior to Ru in kinetics whereas the contrary is the case in thermodynamics. Rh doping elevates the energy height from 0.97 eV on Ni(211) to 1.32 eV and releases 0.39 eV less heat relative to Ni(211), again manifesting a negative effect. Besides the classical Brønsted–Evans–Polanyi relationship, we put forward another two neat linear relations, which can well describe the feature of CO dissociation. The differences of CO adsorption and activation in the IS over pure and doped Ni(211) surfaces are rationalized via electronic structure analysis. The findings presented herein are expected to provide theoretical guidance for catalyst design and optimization in relevant processes.

  4. Iodine-123 program at the TRIUMF laboratory

    International Nuclear Information System (INIS)

    Vincent, J.S.

    1985-01-01

    A research program for the production and utilization of iodine-123 is described. From 1979 to 1982 the spallation of elemental cesium by 500-MeV protons was used to provide 100 mCi/hr at the end of bombardment (EOB). Contaminants were 3% iodine-125 and 0.15% tellurium-121 at EOB + 36 hr. The material from weekly runs was used by remote clinics in Canada for evaluation as a radiochemical and for labeling studies. A new facility at TRIUMF will be operational in 1983 to produce iodine-123 by the (p,5n) reaction

  5. Dissociation dynamics of CH3I in electric spark induced breakdown revealed by time-resolved laser induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Wang, Yang; Liu, Wei-long; Song, Yun-fei; Duo, Li-ping; Liu, Yu-qiang; Yang, Yan-qiang

    2015-01-01

    Highlights: • Emission of electric spark dissociation of CH 3 I is similar to its fs LIBS. • We use fs laser induced breakdown as a simulation for electric spark dissociation. • The I 2 molecule formation is directly observed in the time-resolved LIBS. • Bimolecular collision of I ∗ and CH 3 I is responsible for the formation of I 2 . - Abstract: The electric discharge spark dissociation of gas CH 3 I is found to be similar to its femtosecond laser photodissociation. The almost identical spectra of the two processes show that their initial ionization conditions are very similar. The initial ionization followed by molecular fragmentation is proposed as the dissociation mechanism, in which the characteristic emissions of I + , CH 3 , CH 2 , CH, H, and I 2 are identified as the dissociation products. The emission band of 505 nm I 2 is clearly observed in the time-resolved laser induced breakdown spectroscopy (LIBS). The dynamic curve indicates that I 2 ∗ molecules are formed after the delay time of ∼4.7 ns. The formation of I 2 ∗ molecule results from the bimolecular collision of the highly excited iodine atom I ∗ ( 4 P) and CH 3 I molecule. This dynamical information can help understand the process of electric discharge spark dissociation of CH 3 I

  6. A model to secure a stable iodine concentration in milk

    Directory of Open Access Journals (Sweden)

    Gisken Trøan

    2015-12-01

    Full Text Available Background: Dairy products account for approximately 60% of the iodine intake in the Norwegian population. The iodine concentration in cow's milk varies considerably, depending on feeding practices, season, and amount of iodine and rapeseed products in cow fodder. The variation in iodine in milk affects the risk of iodine deficiency or excess in the population. Objective: The first goal of this study was to develop a model to predict the iodine concentration in milk based on the concentration of iodine and rapeseed or glucosinolate in feed, as a tool to securing stable iodine concentration in milk. A second aim was to estimate the impact of different iodine levels in milk on iodine nutrition in the Norwegian population. Design: Two models were developed on the basis of results from eight published and two unpublished studies from the past 20 years. The models were based on different iodine concentrations in the fodder combined with either glucosinolate (Model 1 or rapeseed cake/meal (Model 2. To illustrate the impact of different iodine concentrations in milk on iodine intake, we simulated the iodine contribution from dairy products in different population groups based on food intake data in the most recent dietary surveys in Norway. Results: The models developed could predict iodine concentration in milk. Cross-validation showed good fit and confirmed the explanatory power of the models. Our calculations showed that dairy products with current iodine level in milk (200 µg/kg cover 68, 49, 108 and 56% of the daily iodine requirements for men, women, 2-year-old children, and pregnant women, respectively. Conclusions: Securing a stable level of iodine in milk by adjusting iodine concentration in different cow feeds is thus important for preventing excess intake in small children and iodine deficiency in pregnant and non-pregnant women.

  7. Studies in iodine metabolism. Progress report, April 1975-- March 1976

    International Nuclear Information System (INIS)

    Van Middlesworth, L.

    1976-01-01

    Investigations during the past twelve months have included the following subjects: factors which influence release of radioiodine from thyroid glands; contamination of commercially available low-iodine diets; effects of hypoxia on release of iodine from thyroid glands of rats and mice; development of practical tests for available iodine in low-iodine diets; reproduction and abnormal thyroglobulin of rats maintained on low-iodine diets; observations on radioactivity in animal thyroids; collaboration with other laboratories regarding radium in bovine thyroids

  8. Method of removing iodine and compounds thereof from gaseous effluents

    International Nuclear Information System (INIS)

    Keener, R.L.; Kittle, P.A.

    1976-01-01

    Anion exchange resins including an acrylic backbone formed by the suspension polymerization of a mixture of an acrylic and a crosslinking monomer are useful in the removal of iodine and iodine compounds from gaseous effluents. Removal of radioactive iodine contaminants, particularly alkyl iodine compounds or hydrogen iodine, under extreme conditions, namely temperatures up to 180 0 C and humidities up to 100 percent, from effluents resulting from a major nuclear accident could probably be adsorbed by these resins described herein

  9. Iodine and thyroid gland with or without nuclear catastrophe

    OpenAIRE

    Kovačev-Zavišić Branka; Novaković-Paro Jovanka; Ičin Tijana; Bajkin Ivana; Todorović-Đilas Ljiljana

    2012-01-01

    Introduction. Iodine, as a trace element, is a necessary and limiting substrate for thyroid gland hormone synthesis. It is an essential element that enables the thyroid gland to produce thyroid hormones thyroxine (T4) and triiodothyronine (T3). Synthesis of Thyroid Hormones and Iodine Metabolism. Three iodine molecules are added to make triiodothyronine, and four for thyroxine - the two key hormones produced by the thyroid gland. Iodine deficiency. The proper daily amount of iodine is r...

  10. Iodine-123 in Western Europe

    International Nuclear Information System (INIS)

    Qaim, S.M.; Stoecklin, G.; Weinreich, R.

    1976-08-01

    The major object of this panel was to obtain information on the state of art of Iodine-123 production in Western Europe. Technical, medical and organizational problems were discussed extensively during the one-day meeting and a stimulating exchange of information between the various 123 I-producers and users has been initiated. Some specific examples of medical application were also included in order to get a feeling of the degree of acceptance by the medical community and the demand for this isotope. The meeting clearly demonstrated the great demand for this isotope but it also showed that the present rate of production is well below the demand. In order to fill this gap, not only further technical development is needed but also the organizational question of distribution has to be solved, perhaps within a network of collaborating cyclotrons, a task which is considerably more difficult in Western Europe than in the USA. (orig./HP) [de

  11. Autoradiography for iodine-125 seeds

    International Nuclear Information System (INIS)

    Alberti, W.; Divoux, S.; Pothmann, B.; Tabor, P.; Hermann, K.P.; Harder, D.

    1993-01-01

    To study the interior design of model 6702 and 6711 iodine-125 seeds, contact autoradiographs were performed using mammography film. Improved resolution was obtained using a pin-hole camera with a hole of 0.1 mm x 0.1 mm. With these techniques, qualitative determination of the relative activity distribution within each seed was possible. The number of the activated resin spheres and the positions of the centers of these spheres can be exactly determined. A model calculation shows that variations in the arrangement of the activated spheres within a seed have a moderate influence on the dose distribution at source distances below 10 mm. Knowing the exact source configuration may be useful when comparing dose calculations with measured data for model 6702 125 I seeds which are currently employed in ophthalmic plaque and implant therapy of other tumors. 16 refs., 5 figs., 2 tabs

  12. Analysis of iodine content in seaweed by GC-ECD and estimation of iodine intake

    Directory of Open Access Journals (Sweden)

    Tai Sheng Yeh

    2014-06-01

    Full Text Available Edible seaweed products have been consumed in many Asian countries. Edible seaweeds accumulate iodine from seawater, and are therefore a good dietary source of iodine. An adequate consumption of seaweed can eliminate iodine deficiency disorders, but excessive iodine intake is not good for health. The recommended dietary reference intake of 0.15 mg/d and 0.14 mg/d for iodine has been established in the United States and Taiwan, respectively. In this study, 30 samples of seaweed were surveyed for iodine content. The samples included 10 nori (Porphyra, 10 wakame (Undaria, and 10 kombu (Laminaria products. The iodine in seaweed was derivatized with 3-pentanone and detected by gas chromatography-electron capture detector (GC-ECD. The method detection limit was 0.5 mg/kg. The iodine content surveyed for nori was 29.3–45.8 mg/kg, for wakame 93.9–185.1 mg/kg, and for kombu 241–4921 mg/kg. Kombu has the highest average iodine content 2523.5 mg/kg, followed by wakame (139.7 mg/kg and nori (36.9 mg/kg. The GC-ECD method developed in this study is a low-cost alternative to inductively coupled plasma-optical emission spectroscopy for iodine detection in seaweeds. The iodine intake from seaweed in the current survey was calculated and compared with the iodine dietary reference intake of Taiwan. The risk and benefit of seaweed consumption is also discussed.

  13. Does iodine gas released from seaweed contribute to dietary iodine intake?

    Science.gov (United States)

    Smyth, P P A; Burns, R; Huang, R J; Hoffman, T; Mullan, K; Graham, U; Seitz, K; Platt, U; O'Dowd, C

    2011-08-01

    Thyroid hormone levels sufficient for brain development and normal metabolism require a minimal supply of iodine, mainly dietary. Living near the sea may confer advantages for iodine intake. Iodine (I(2)) gas released from seaweeds may, through respiration, supply a significant fraction of daily iodine requirements. Gaseous iodine released over seaweed beds was measured by a new gas chromatography-mass spectrometry (GC-MS)-based method and iodine intake assessed by measuring urinary iodine (UI) excretion. Urine samples were obtained from female schoolchildren living in coastal seaweed rich and low seaweed abundance and inland areas of Ireland. Median I(2) ranged 154-905 pg/L (daytime downwind), with higher values (~1,287 pg/L) on still nights, 1,145-3,132 pg/L (over seaweed). A rough estimate of daily gaseous iodine intake in coastal areas, based upon an arbitrary respiration of 10,000L, ranged from 1 to 20 μg/day. Despite this relatively low potential I(2) intake, UI in populations living near a seaweed hotspot were much higher than in lower abundance seaweed coastal or inland areas (158, 71 and 58 μg/L, respectively). Higher values >150 μg/L were observed in 45.6% of (seaweed rich), 3.6% (lower seaweed), 2.3% (inland)) supporting the hypothesis that iodine intake in coastal regions may be dependent on seaweed abundance rather than proximity to the sea. The findings do not exclude the possibility of a significant role for iodine inhalation in influencing iodine status. Despite lacking iodized salt, coastal communities in seaweed-rich areas can maintain an adequate iodine supply. This observation brings new meaning to the expression "Sea air is good for you!"

  14. Iodine binding to humic acid.

    Science.gov (United States)

    Bowley, H E; Young, S D; Ander, E L; Crout, N M J; Watts, M J; Bailey, E H

    2016-08-01

    The rate of reactions between humic acid (HA) and iodide (I(-)) and iodate (IO3(-)) have been investigated in suspensions spiked with (129)I at concentrations of 22, 44 and 88 μg L(-1) and stored at 10 °C. Changes in the speciation of (129)I(-), (129)IO3(-) and mixed ((129)I(-) + (129)IO3(-)) spikes were monitored over 77 days using liquid chromatography inductively coupled plasma mass spectrometry (LC-ICP-MS). In suspensions spiked with (129)I(-) 25% of the added I(-) was transformed into organic iodine (Org-(129)I) within 77 days and there was no evidence of (129)IO3(-) formation. By contrast, rapid loss of (129)IO3(-) and increase in both (129)I(-) and Org-(129)I was observed in (129)IO3(-)-spiked suspensions. However, the rate of Org-(129)I production was greater in mixed systems compared to (129)IO3(-)-spiked suspensions with the same total (129)I concentration, possibly indicating IO3(-)I(-) redox coupling. Size exclusion chromatography (SEC) demonstrated that Org-(129)I was present in both high and low molecular weight fractions of the HA although a slight preference to bond with the lower molecular weight fractions was observed indicating that, after 77 days, the spiked isotope had not fully mixed with the native (127)I pool. Iodine transformations were modelled using first order rate equations and fitted rate coefficients determined. However, extrapolation of the model to 250 days indicated that a pseudo-steady state would be attained after ∼200 days but that the proportion of (129)I incorporated into HA was less than that of (127)I indicating the presence of a recalcitrant pool of (127)I that was unavailable for isotopic mixing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Development of Databases on Iodine in Foods and Dietary Supplements

    Science.gov (United States)

    Ershow, Abby G.; Skeaff, Sheila A.; Merkel, Joyce M.; Pehrsson, Pamela R.

    2018-01-01

    Iodine is an essential micronutrient required for normal growth and neurodevelopment; thus, an adequate intake of iodine is particularly important for pregnant and lactating women, and throughout childhood. Low levels of iodine in the soil and groundwater are common in many parts of the world, often leading to diets that are low in iodine. Widespread salt iodization has eradicated severe iodine deficiency, but mild-to-moderate deficiency is still prevalent even in many developed countries. To understand patterns of iodine intake and to develop strategies for improving intake, it is important to characterize all sources of dietary iodine, and national databases on the iodine content of major dietary contributors (including foods, beverages, water, salts, and supplements) provide a key information resource. This paper discusses the importance of well-constructed databases on the iodine content of foods, beverages, and dietary supplements; the availability of iodine databases worldwide; and factors related to variability in iodine content that should be considered when developing such databases. We also describe current efforts in iodine database development in the United States, the use of iodine composition data to develop food fortification policies in New Zealand, and how iodine content databases might be used when considering the iodine intake and status of individuals and populations. PMID:29342090

  16. Influencing factors on iodine content of cow milk.

    Science.gov (United States)

    Flachowsky, Gerhard; Franke, Katrin; Meyer, Ulrich; Leiterer, Matthias; Schöne, Friedrich

    2014-01-01

    Iodine is an essential trace element for humans and animals, and it is incorporated into the thyroid hormones such as thyroxine and triiodothyronine, which have multiple functions in energy metabolism and growth, but also as transmitter of nervous stimuli and as an important factor for brain development. Because of the small range between iodine requirements and the upper level for humans (between 1:2.5 and 3), the requirements should be met, but excesses should be avoided. One of the most important iodine sources for humans is milk of ruminants. Therefore, various influencing factors on the iodine content of milk of ruminants should be analyzed in the paper. The iodine content of milk depends on many factors, such as iodine content and level of iodine supplementation of feed, iodine source, iodine antagonists such as glucosinolates in the feed, farm management, teat dipping with iodine-containing substances, and milk processing in the dairy. The effects of some factors on the iodine content of milk are demonstrated and discussed. Feed iodine supplementation has the main effect on milk iodine. However, the iodine content of milk may vary considerably depending on many other influencing factors. As a consequence of preventive consumer protection, the European Food Safety Authority proposed a reduction in the iodine upper level for lactating ruminants from 5 to 2 mg/kg complete feed.

  17. Recycling of iodine in fore-arc areas: evidence from the iodine brines in Chiba, Japan

    Science.gov (United States)

    Muramatsu, Yasuyuki; Fehn, Udo; Yoshida, Satoshi

    2001-11-01

    The distribution of iodine in the Earth's crust is dominated by its accumulation in marine sediments. If fluxes between terrestrial and marine compartments are considered, however, a significant imbalance exists between known sources and sinks of iodine. We present here evidence from the fore-arc area near Chiba, Japan, the world's largest brine-iodine producing area, that iodine is mobilized from marine sediments during the early stages of subduction. Based on detailed chemical analyses of 22 brines and 129I dating of 13 of these samples collected from the Kazusa Formation, we show that iodine in these fluids is derived from organic-rich marine sediments with a minimum age of 50 Myr. Geochemical characteristics of the brines and the age of the iodine indicate that the iodine enrichment is caused by mobilization from subducting marine sediments and not by derivation from the host formation (age 1-2 Myr). The direct return of iodine from marine sediments into the oceans during the subduction of oceanic plates could provide the missing link in the iodine cycle and be an important pathway also in the marine cycle of carbon.

  18. Iodine deficiency in pregnancy in Denmark. Regional variations and frequency of individual iodine supplementation

    DEFF Research Database (Denmark)

    Nøhr, S B; Laurberg, P; Børlum, K G

    1993-01-01

    Iodine requirements are increased during pregnancy and lactation and adequate iodine intake is important for normal brain development of the fetus/newborn child. The aim of the present study was to evaluate the extent to which this increase in iodine requirement is met in pregnant women living...... micrograms/g creatinine). These values are far below internationally recommended levels. The consequences remain to be evaluated and no firm recommendations can be given. It seems reasonable, however, to recommend a high intake of food containing iodine (e.g. milk products) during pregnancy and lactation...

  19. Effect of Bioaerosol on the Release of Iodine from Iodine Treated Filters

    Science.gov (United States)

    2011-12-01

    shows a schematic of the experimental system. Bioaerosols were generated by a six-jet Collison nebulizer at 7 Lpm. Virus concentrations in the...AFRL-RX-TY-TP-2012-0004 EFFECT OF BIOAEROSOL ON THE RELEASE OF IODINE FROM IODINE TREATED FILTERS Chang-Yu Wu, Hsing-Wang Li, Myung-Heui...Effect of Bioaerosol on the Release of Iodine from Iodine Treated Filters FA8650-06-C-5913 0602102F GOVT L0 QL102008 Wu, Chang-Yu; Li, Hsing-Wang; Woo

  20. The retention of iodine by iodine filters in nuclear power plants in the case of fire

    International Nuclear Information System (INIS)

    Giraud, V.

    1985-01-01

    Due to the liberation of considerable amounts of gaseous combustion products, fires in nuclear power plants may lead to a deterioration in the retention of radioiodine by iodine filters. The combustion products of the burnable materials, i.e., insulations, lubricants and paints, vary considerably with the development of the fire. Combustion product analyses of these materials have been performed only to a limited extent. The reaction of iodine with combustion products as well as the retention of the resulting iodine reaction products by sorbents have not yet been investigated. The reduction in the removal efficiencies of iodine sorbents due to the presence of combustion products is unknown. (orig.) [de

  1. Emissivity of the pulsed capacitive discharge in helium-iodine and neon-iodine mixtures

    Science.gov (United States)

    Shuaibov, A. K.; Minya, A. I.; Gomoki, Z. T.; Laslov, G. E.

    2009-01-01

    The emission parameters of a pulsed capacitive discharge initiated in helium-iodine and neon-iodine mixtures are reported. The discharge plasma emits at wavelengths of 183.0 and 206.2 nm, which correspond to iodine atom spectral lines. The capacitive discharge is initiated in a cylindrical quartz tube with an electrode distance of 10 cm. The discharge radiation is optimized in exciting pulse repetition rate and helium and neon pressures in He(Ne)-I2 mixtures. The optimal pressures of helium, neon, and iodine vapor fall into the ranges 0.8-2.0 kPa, 0.5-1.0 Pa, and ≤60 Pa, respectively.

  2. Radiative capture versus Coulomb dissociation

    International Nuclear Information System (INIS)

    Esbensen, H.; Physics

    2006-01-01

    Measurements of the Coulomb dissociation of 8 B have been used to infer the rate of the inverse radiative proton capture on 7 Be. The analysis is usually based on the assumptions that the two processes are related by detailed balance and described by E1 transitions. However, there are corrections to this relation. The Coulomb form factors for the two processes, for example, are not identical. There are also E2 transitions and higher-order effects in the Coulomb dissociation, and the nuclear induced breakup cannot always be ignored. While adding first-order E2 transitions enhances the decay energy spectrum, the other mechanisms cause a suppression at low relative energies. The net result may accidentally be close to the conventional first-order E1 calculation, but there are differences which cannot be ignored if accuracies of 10% or better are needed

  3. Radiative Capture versus Coulomb Dissociation

    International Nuclear Information System (INIS)

    Esbensen, Henning

    2006-01-01

    Measurements of the Coulomb dissociation of 8B have been used to infer the rate of the inverse radiative proton capture on 7Be. The analysis is usually based on the assumptions that the two processes are related by detailed balance and described by E1 transitions. However, there are corrections to this relation. The Coulomb form factors for the two processes, for example, are not identical. There are also E2 transitions and higher-order effects in the Coulomb dissociation, and the nuclear induced breakup cannot always be ignored. While adding first-order E2 transitions enhances the decay energy spectrum, the other mechanisms cause a suppression at low relative energies. The net result may accidentally be close to the conventional first-order E1 calculation, but there are differences which cannot be ignored if accuracies of 10% or better are needed

  4. Hydrogen dissociation on metal surfaces

    OpenAIRE

    Wijzenbroek, M.

    2016-01-01

    Dissociative chemisorption is an important reaction step in many catalytic reactions. An example of such a reaction is the Haber-Bosch process, which is used commercially to produce ammonia, an important starting material in the production of fertilisers. In theoretical descriptions of such chemical processes often approximations need to be made in order to keep the computational cost feasible, such as fixing the surface atoms in place, rather than allowing them to vibrate. In this work, seve...

  5. Dissociative attachment to lithium dimers

    International Nuclear Information System (INIS)

    Wadehra, J.M.

    1987-01-01

    The cross sections and the rates of production of negative ions of atomic lithium by the process of dissociative electron attachment to lithium dimers are obtained by using the resonant scattering theory. Both the cross sections as well as the rates of attachment are enhanced if the lithium molecule is initially vibrationally excited. General expressions for approximately obtaining the rates of electron attachment to any vibrational level of Li 2 are presented

  6. Paraphilia from a dissociative perspective.

    Science.gov (United States)

    Ross, Colin A

    2008-12-01

    A dissociative structural model of the psyche can account for a wide range of symptoms across many DSM-IV categories, including sexual compulsions and addictions. The model leads to a distinct overall plan of treatment and a set of operationalized interventions aimed at integration of the self, rather than suppression of impulses. The model could be tested first in epidemiological studies and later in treatment outcome studies.

  7. Autonoesis and dissociative identity disorder.

    Science.gov (United States)

    Morton, John

    2018-01-01

    Dissociative identity disorder is characterised by the presence in one individual of two or more alternative personality states (alters). For such individuals, the memory representation of a particular event can have full episodic, autonoetic status for one alter, while having the status of knowledge or even being inaccessible to a second alter. This phenomenon appears to create difficulties for a purely representational theory and is presented to Mahr & Csibra (M&C) for their consideration.

  8. A mathematical model for iodine kinetics

    International Nuclear Information System (INIS)

    Silva, E.A.T. da.

    1976-01-01

    A mathematical model for the iodine kinetics in thyroid is presented followed by its analytical solution. An eletroanalogical model is also developed for a simplified stage and another is proposed for the main case [pt

  9. Air filtration plants of wall-type for separation of fission iodine in nuclear reactors

    International Nuclear Information System (INIS)

    Stiehl, H.H.; Neumann, M.; Sinhuber, D.

    1976-01-01

    The increasing density of nuclear power stations and increased safety requirements will lead in future to higher flow rates and longer residence times in the adsorption filter layer of the iodine sorption filter plants of nuclear power stations. The safety requirements in the Federal Republic of Germany have been complied with so far in the conventional way by means of duct-type filter constructions. For the higher flow rates and longer residence times necessary in future, we propose a filter construction of wall-type, which complies with the safety regulations of the Federal Republic of Germany. The economic and technical advantages are discussed

  10. [Clinical Handling of Patients with Dissociative Disorders].

    Science.gov (United States)

    Okano, Kenichiro

    2015-01-01

    This paper discusses the way informed psychiatrists are expected to handle dissociative patients in clinical situations, with a specific focus on dissociative identity disorders and dissociative fugue. On the initial interview with dissociative patients, information on their history of trauma and any nascent dissociative symptoms in their childhood should be carefully obtained. Their level of stress in their current life should also be assessed in order to understand their symptomatology, as well as to predict their future clinical course. A psychoeducational approach is crucial; it might be helpful to give information on dissociative disorder to these patients as well as their family members in order to promote their adherence to treatment. Regarding the symptomatology of dissociative disorders, detailed symptoms and the general clinical course are presented. It was stressed that dissociative identity disorder and dissociative fugue, the most high-profile dissociative disorders, are essentially different in their etiology and clinical presentation. Dissociative disorders are often confused with and misdiagnosed as psychotic disorders, such as schizophrenia. Other conditions considered in terms of the differential diagnosis include borderline personality disorder as well as temporal lobe epilepsy. Lastly, the therapeutic approach to dissociative identity disorder is discussed. Each dissociative identity should be understood as potentially representing some traumatically stressful event in the past. The therapist should be careful not to excessively promote the creation or elaboration of any dissociative identities. Three stages are proposed in the individual psychotherapeutic process. In the initial stage, a secure environment and stabilization of symptoms should be sought. The second stage consists of aiding the "host" personality to make use of other more adaptive coping skills in their life. The third stage involves coaching as well as continuous awareness of

  11. Iodine dynamics in the terrestrial environment

    OpenAIRE

    Bowley, Hannah E.

    2013-01-01

    The aim of this work was to investigate the effect of soil properties on soil iodine dynamics and uptake to plants. Soil and vegetation samples were collected from across eastern Northern Ireland (NI) to form the basis of most experimental work; samples from the Rothamsted Park Grass archive were used to investigate the role of changing soil chemistry through time and due to selected fertiliser applications; and iodine dynamics in humic acid (HA) were studied to improve understanding of the r...

  12. A Simple Adsorption Experiment

    Science.gov (United States)

    Guirado, Gonzalo; Ayllon, Jose A.

    2011-01-01

    The study of adsorption phenomenon is one of the most relevant and traditional physical chemistry experiments performed by chemistry undergraduate students in laboratory courses. In this article, we describe an easy, inexpensive, and straightforward way to experimentally determine adsorption isotherms using pieces of filter paper as the adsorbent…

  13. Structure sensitivity in adsorption

    DEFF Research Database (Denmark)

    Hammer, Bjørk; Nielsen, Ole Holm; Nørskov, Jens Kehlet

    1997-01-01

    The structure sensitivity of CO adsorption on different flat, stepped, kinked and reconstructed Pt surfaces is studied using large-scale density-functional calculations. We find an extremely strong structure sensitivity in the adsorption energy with variations up to 1 eV (or 100%) from one...

  14. Study of iodine-iodate isotopic exchange reaction in neutral aqueous solutions by radiotracer technique

    International Nuclear Information System (INIS)

    Tripathi, R.; Ram, K.D.

    1993-01-01

    The isotopic exchange of iodine atoms in neutral aqueous solutions of iodate ions and iodine (in KI) is found to obey the rate law R = k [IO 3 - ] 0.4 [I 2 ] 1.2 at 175 o C. The addition of neutral ionic salts, e.g. KCl and KNO 3 , in the reaction mixture showed a slight catalytic effect on the exchange rate. Further, the kinetic salt effect indicated the involvement of at least one neutral species on the rate-determining step. The activation energy in neutral aqueous solutions of iodate ions and iodine is found to be 86 ± 3 kJ mol -1 , which decreases in the presence of KCl (79 ± 3 kJ mol -1 and KNO 3 (82 + 3 kJ mol -1 ). The activation parameters, viz. free energy of activation, enthalpy of activation and entropy of activation, were also calculated. Based on these results, an association-dissociation type of reaction mechanism is proposed for this exchange reaction in neutral aqueous medium, similar to that proposed earlier for iodide-iodate isotopic exchange reaction in neutral aqueous solutions, nitrate eutectic melts and iodide-iodate melts. (author)

  15. Iodine nutritional status in Asturian schoolchildren.

    Science.gov (United States)

    Riestra Fernández, María; Menéndez Torre, Edelmiro; Díaz Cadórniga, Francisco; Fernández Fernández, Juan Carlos; Delgado Álvarez, Elías

    2017-11-01

    Iodine deficiency is a public health problem, and iodine nutritional status should therefore be regularly measured. To ascertain iodine nutritional status in Asturias and its relation to use of iodized salt and to other sociodemographic and nutritional parameters. A descriptive, observational study was conducted in a random sample of schoolchildren aged 5 to 14 years, in whom urinary iodine levels were measured by high-performance liquid chromatography. Families completed a survey on use of iodized salt, consumption of dairy products and fish, and sociodemographic data. The study sample consisted of 705 schoolchildren (51.1% females) with a mean age of 9.9 years (SD 2.6). In a total of 620 valid measurements, mean urinary iodine level was 204.1 μg/L (SD 120.6), while the median value was 180.7 μg/L (P 25 -P 75 : 124-252.3 μg/L, interquartile range 128.3 μg/L). Urinary iodine levels were y SED. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Modern and past volcanic degassing of iodine

    Science.gov (United States)

    Bureau, H.; Auzende, A.-L.; Marocchi, M.; Raepsaet, C.; Munsch, P.; Testemale, D.; Mézouar, M.; Kubsky, S.; Carrière, M.; Ricolleau, A.; Fiquet, G.

    2016-01-01

    We have monitored iodine degassing from a melt to a water vapor during decompression (i.e. magma ascent). Experiments have been performed by combining diamond anvil cells experiments with synchrotron X-rays fluorescence analysis. Partition coefficients DIfluid/melt measured for a pressure and temperature range of 0.1-1.8 GPa and 500-900 °C, range from 41 to 1.92, values for room conditions DIfluid/glass (quenched samples) are equal to or higher than 350. We show that iodine degassing with water is earlier and much more efficient than for lighter halogen elements, Cl and Br. Iodine is totally degassed from the silicate melt at room conditions. By applying these results to modern volcanology, we calculate an annual iodine flux for subduction related volcanism of 0.16-2.4 kt yr-1. We suggest that the natural iodine degassing may be underestimated, having possible consequences on the Earth's ozone destruction cycle. By applying this results to the Early Earth, we propose a process that may explain the contrasted signature of I, Br and Cl, strongly depleted in the bulk silicate Earth, the most depleted being iodine, whereas fluorine is almost enriched. The Earth may have lost heavy halogen elements during an early water degassing process from the magma ocean.

  17. Dietary Iodine Intake of the Australian Population after Introduction of a Mandatory Iodine Fortification Programme

    Directory of Open Access Journals (Sweden)

    Karen Charlton

    2016-11-01

    Full Text Available To address mild iodine deficiency in Australia, a mandatory fortification program of iodised salt in bread was implemented in 2009. This study aimed to determine factors associated with achieving an adequate dietary iodine intake in the Australian population post-fortification, and to assess whether bread consumption patterns affect iodine intake in high-risk groups. Using nationally representative data of repeated 24-h dietary recalls from the 2011–2012 Australian National Nutrition and Physical Activity Survey, dietary iodine intakes and food group contributions were compared by age, socioeconomic status (SES, and geographical remoteness (N = 7735. The association between fortified bread intake and adequacy of iodine intake (meeting age and sex-specific Estimated Average Requirements was investigated using logistic regression models in women of childbearing age 14–50 years (n = 3496 and children aged 2–18 years (n = 1772. The effect of SES on bread consumption was further investigated in a sub group of children aged 5–9 years (n = 488. Main sources of iodine intake at the time of the survey were cereal and cereal products, followed by milk products and dishes. Differences in iodine intake and dietary iodine habits according to age, SES and location were found (p < 0.001 for women of child-bearing age. Fortified bread consumption at ≥100 g/day was associated with five times greater odds of achieving an adequate iodine intake (OR 5.0, 95% CI 4.96–5.13; p < 0.001 compared to lower bread consumption in women and 12 times in children (OR 12.34, 95% CI 1.71–89.26; p < 0.001. Disparities in dietary iodine intake exist within sectors of the Australian population, even after mandatory fortification of a staple food. On-going monitoring and surveillance of iodine status is required.

  18. Radioactive nuclide adsorption

    International Nuclear Information System (INIS)

    Fukushima, Kimichika.

    1982-01-01

    Purpose: To improve the efficiency of a radioactive nuclide adsorption device by applying a nickel plating on a nickel plate to render the surface active. Constitution: A capturing device for radioactive nuclide such as manganese 54, cobalt 60, 58 and the like is disposed to the inside of a pipeway provided on the upper portion of fuel assemblies through which liquid sodium as the coolant for LMFBR type reactor is passed. The device comprises a cylindrical adsorption body and spacers. The adsorption body is made of nickel and applied with a nickel plating on the surface thereof. The surface of the adsorption body is unevened to result in disturbance in the coolant and thereby improve the adsorptive efficiency. (Kawakami, Y.)

  19. National trends in iodine nutrition: is everyone getting enough?

    Science.gov (United States)

    Pearce, Elizabeth N

    2007-09-01

    Iodine deficiency is an important public health problem worldwide. Until the 1920s, endemic iodine deficiency disorders were prevalent in the Great Lakes, Appalachian, and Northwestern regions of the United States. Iodized salt was responsible for eliminating endemic goiter in the United States and remains the mainstay of iodine deficiency disorder eradication efforts worldwide. Although urinary iodine values have decreased by 50% since the early 1970s, the United States remains iodine sufficient. However, U.S. iodine nutrition, particularly among women of childbearing age, may remain an area worthy of public health concern. There is a wide amount of variation in the iodine content of some common foods, and the iodine content of foods is not well reflected by package labeling. There needs to be increased awareness of the importance of adequate iodine nutrition, particularly during pregnancy and lactation, among the U.S. public.

  20. Ultraviolet gas-discharge lamp on iodine molecules

    Science.gov (United States)

    Shuaibov, A. K.; Minya, A. I.; Gomoki, Z. T.; Kalyuzhnaya, A. G.; Shchedrin, A. I.

    2010-08-01

    The emission characteristics of a pulsed-periodic UV radiation source are reported. The source excited by a pulsed-periodic capacitive discharge initiated in helium-iodine vapor, neon-iodine vapor, or krypton-iodine vapor mixtures radiates in the spectral range 200-450 nm. It is shown that most of the plasma radiation power concentrates in the integral line of the iodine atom (206.2 nm) and in the D'- A' band of the iodine molecule with a maximum at 342 nm. The radiation intensity of the lamp is optimized in accordance with the partial pressure of the inert gases. The discharge plasma parameters that are of interest for simulating the process kinetics and the output characteristics of an UV source based on molecular iodine, atomic iodine, and xenon iodide are calculated in helium-iodine vapor and xenon-iodine vapor mixtures.

  1. Iodine Supplementation in Pregnancy and the Dilemma of Ambiguous Recommendations

    DEFF Research Database (Denmark)

    Andersen, Stine Linding; Laurberg, Peter

    2016-01-01

    Iodine requirements are increased during pregnancy, predominantly caused by an increase in renal iodide clearance and in the use of iodine for thyroid hormone production. Because iodine deficiency (ID) in pregnancy may be associated with neurodevelopmental deficits in the offspring, a pertinent...... question is at what level of iodine intake pregnant women should be advised to take iodine-containing supplements. The consensus reached by the WHO/UNICEF/ICCIDD in 2007 was that pregnant women should not be recommended to take iodine-containing supplements if the population in general had been iodine...... sufficient for at least 2 years. However, guidance on this differs between scientific societies. This review discusses iodine supplementation in pregnancy. Based on current evidence, the recommendations given by WHO/UNICEF/ICCIDD in 2007 provide a valid guidance on the use of iodine supplements in pregnant...

  2. Highly Efficient Enrichment of Volatile Iodine by Charged Porous Aromatic Frameworks with Three Sorption Sites.

    Science.gov (United States)

    Yan, Zhuojun; Yuan, Ye; Tian, Yuyang; Zhang, Daming; Zhu, Guangshan

    2015-10-19

    The targeted synthesis of a series of novel charged porous aromatic frameworks (PAFs) is reported. The compounds PAF-23, PAF-24, and PAF-25 are built up by a tetrahedral building unit, lithium tetrakis(4-iodophenyl)borate (LTIPB), and different alkyne monomers as linkers by a Sonogashira-Hagihara coupling reaction. They possess excellent adsorption properties to organic molecules owing to their "breathing" dynamic frameworks. As these PAF materials assemble three effective sorption sites, namely the ion bond, phenyl ring, and triple bond together, they exhibit high affinity and capacity for iodine molecules. To the best of our knowledge, these PAF materials give the highest adsorption values among all porous materials (zeolites, metal-organic frameworks, and porous organic frameworks) reported to date. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Pengaruh Aktivasi Arang Aktif dari Tongkol Jagung dan Tempurung Kelapa Terhadap Luas Permukaan dan Daya Jerap Iodin

    Directory of Open Access Journals (Sweden)

    Lela Mukmilah Yuningsih

    2016-05-01

    Full Text Available The activated charcoal can be produced from various raw material which contains carbon such as corn cobs and coconut shell. Generally, activated charcoal made through activation process with added chemical materials. The kind of activator will give different influence on surface area or pores volume of the result activated charcoal. In this study, will be made activated charcoal from corn cobs and activated by physical and chemical with KOH activator. Carbonation process is performed at 800oC for 2 hours and followed by chemical activation process by KOH with mass ratio water: charcoal: KOH is 1:1:4, then activated by physical at 600oC for 4 hours. Conducted test on sample contain iodine adsorption and SEM. As a result, iodine adsorption of activated charcoal indicated at KOH 20%. the best adsorption of coconut shell activated charcoal is 1240.233 mg/g with surface area 2352.851 m2/g, while corn cobs activated charcoal is 1133.757 mg/g with surface area 2150.866 m2/g. Morphology of activated charcoal with KOH 20% have pore structure with high 22.63 µm and wide 26.41 µm, the resulting pore size included into macropores structure. Keywords: Activated charcoal, carbonation, activation, adsorption, surface area. DOI: http://dx.doi.org/10.15408/jkv.v2i1.3091

  4. Thyroid volume and urinary iodine in European schoolchildren: standardization of values for assessment of iodine deficiency

    NARCIS (Netherlands)

    Delange, F.; Benker, G.; Caron, P.; Eber, O.; Ott, W.; Peter, F.; Podoba, J.; Simescu, M.; Szybinsky, Z.; Vertongen, F.; Vitti, P.; Wiersinga, W.; Zamrazil, V.

    1997-01-01

    Up to 1992, most European countries used to be moderately to severely iodine deficient. The present study aimed at evaluating possible changes in the status of iodine nutrition in 12 European countries during the past few years. Thyroid volume was measured by ultrasonography in 7599 schoolchildren

  5. Development of the chemical oxygen-iodine laser (COIL) with chemical generation of atomic iodine

    Czech Academy of Sciences Publication Activity Database

    Kodymová, Jarmila; Špalek, Otomar; Jirásek, Vít; Čenský, Miroslav; Hager, G. D.

    2003-01-01

    Roč. 77, - (2003), s. 331-336 ISSN 0947-8396 R&D Projects: GA MŠk LN00A100 Institutional research plan: CEZ:AV0Z1010914 Keywords : atomic iodine * atomic chlorine * chemical oxygen-iodine laser(COIL) Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.220, year: 2003

  6. Longitudinal study of iodine in toenails following IV administration of an iodine-containing contrast agent

    International Nuclear Information System (INIS)

    Spate, V.L.; Morris, J.S.; Nichols, T.A.; Baskett, C.K.; Mason, M.M.; Horsman, T.L.; McDougall, I.R.

    1998-01-01

    The literature on the relationship between diet and thyroid cancer (TC) risk and the higher incidence of TC among Asian immigrants to the US compared to second and third generation subgroups has prompted epidemiologists to hypothesize that increased levels of iodine consumption may be associated with TC risk, particularly among persons with a history of clinical or subclinical thyroid dysfunction. At the University of Missouri Research Reactor (MURR), we have applied epiboron neutron activation analysis to investigate human nails as a dietary monitor for iodine. Preliminary studies have indicated a positive correlation between dietary iodine intake and the concentration of iodine in toenails. However, these studies are confounded by high iodine levels (up to 30 ppm) in approximately 5% of the nails studied. We hypothesize that, in the subjects we have studied, the high iodine levels may be due to iodine-containing medications, in particular contrast-agents containing iopamidol. This paper will report on longitudinal studies using contrast agent subjects who where followed-up for almost two years compared to a longitudinal control and a population mean. Based on this study, we suggest that iodine-containing contrast agents contaminate nail samples via non-specific binding in the short term followed by incorporation in the nail as a result of absorption. (author)

  7. Sensitivity analysis on the deposition of inhaled radioactive iodine and the effectiveness of iodine prophylaxis

    International Nuclear Information System (INIS)

    Matsunaga, Takeshi; Kobayashi, Kensuke

    2001-01-01

    The prophylactic use of stable iodine is one of the protective measures during a nuclear emergency. In order to know the resultant radiation dose to the thyroid gland and the effectiveness of iodine prophylaxis in the case of Japanese, a sensitivity analysis was performed for related physiological parameters for Japanese. As a result, the variances in the deposition efficiency of radioactive iodine aerosol in the respiratory tract due to changes in the respiratory parameters were found rather small between the standard Caucasian and Japanese. The changes due to the radioactive iodine aerosol size were more significant, suggesting the importance of understanding the physico-chemical status of aerobic radioiodine released in a nuclear emergency. Concerning the metabolic parameters of iodine, the result of the sensitivity analysis based on an iodine metabolic model showed that the most critical parameters are those which describe the transport of stable and radioactive iodine from the blood compartment to the thyroid gland. Accordingly, a confirmation of the transport model and the related parameters for Japanese are essential to clarify the effectiveness of iodine prophylaxis to reduce thyroid gland exposure of Japanese. (author)

  8. The impact of iodised salt or iodine supplements on iodine status during pregnancy lactation and infancy

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2007-01-01

    Objectives: Monitoring of iodine status during pregnancy, lactation and infancy is difficult as there are no established reference criteria for urinary iodine concentration (UI) for these groups; so it is uncertain whether iodized salt programs meet the needs of these life stages. Design and

  9. Impact evaluation of iron & iodine fortified salt.

    Science.gov (United States)

    Nair, K M; Brahmam, G N; Ranganathan, S; Vijayaraghavan, K; Sivakumar, B; Krishnaswamy, K

    1998-11-01

    As a novel approach to tackle the problems of iron deficiency anaemia and iodine deficiency disorders (IDDs), which often coexist, the National Institute of Nutrition has developed iron and iodine fortified common salt (double fortified salt-DFS) as a public health measure. This salt has undergone a battery of laboratory and field tests to evaluate its feasibility for use in a national programme. The DFS is designed to provide 1 mg of iron and 15 micrograms of iodine per gram of common salt. This was made possible by the inclusion of a polyphosphate stabilizer, sodium hexametaphosphate (SHMP) at 1 per cent level. The stability of iron and iodine was found to be good up to 6 months. However, the stability of iodine depended upon the quality of the salt used for fortification. The biological effects of long-term consumption of DFS were evaluated in experimental rats and in field trials. Both iron and iodine from the salt were found to be biologically available in regenerating haemoglobin and in increasing excretion of iodine in urine. When this salt was tested in tribal villages endemic for goitre and iron deficiency anaemia, the bioresponse was good with regard to the iodine status but was not uniform in all segments with regard to iron, probably due to confounding variables. In a study carried out in residential school children where such variables did not exist, DFS was found to have significant impact on haemoglobin status in anaemic children and improved their urinary iodine excretion. The consumption of DFS for 2 yr did not have any adverse effects in school children as well as in the tribal population. Parameters related to calcium homeostasis were not altered in children receiving DFS. Histopathological examination of tissues and radiological examination of bone did not reveal any abnormality in DFS fed rats. Similarly serum and urinary parameters related to calcium and phosphorus were not altered in DFS fed rats. Therefore, DFS is presented as a feasible and

  10. Theoretical insights into the effects of the diameter and helicity on the adsorption of formic acid on silicon carbide nanotube

    Energy Technology Data Exchange (ETDEWEB)

    Chen Ying; Wang Hongxia; Zhao Jingxiang, E-mail: xjz_hmily@yahoo.com.cn; Wang Xiaoguang; Cai Qinghai [Harbin Normal University, Key Lab for Design and Synthesis of Functionalized Materials and Green Catalysis, School of Chemistry and Chemical Engineering (China); Ding Yihong, E-mail: yhdd@jlu.edu.cn [Jilin University, State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry (China); Wang Xuanzhang [Harbin Normal University, Key Lab for Design and Synthesis of Functionalized Materials and Green Catalysis, School of Chemistry and Chemical Engineering (China)

    2012-01-15

    The anchoring of small organic molecules onto the semiconductor surface has a great application for developing various molecular devices, such as novel solar cells, fuel cells, hybrid systems, sensors, and so on. In the present work, by carrying out detailed density-functional theory calculations, we have investigated the adsorption of the formic acid (HCOOH) molecule on planar and various curved silicon carbide (SiC) nanotubes. By considering both the molecular and dissociative adsorptions of HCOOH on these SiC nanomaterials, we found that the HCOOH molecule prefers to dissociate into HCOO and H group. Interestingly, different adsorption modes were found for HCOOH on SiC nanotubes, i.e. dissociative monodentate or bidentate adsorption, which depends on the tube diameter and helicity. For (n, 0) SiC nanotube, the monodentate adsorption mode is energetically favorable when n is less than 10. However, HCOOH prefers to be adsorbed on other (n, 0) SiC nanotubes in a bridged bidentate mode, which is similar to those of on (n, n) SiC nanotubes or planar SiC sheet. Moreover, upon HCOOH adsorption, these SiC nanomaterials remain to be of the semiconducting nature and their band gaps are decreased to different degrees. In addition, we also explored the effects of HCOOH coverage on its adsorption on SiC nanotube.

  11. Study on Shale Adsorption Equation Based on Monolayer Adsorption, Multilayer Adsorption, and Capillary Condensation

    Directory of Open Access Journals (Sweden)

    Qing Chen

    2017-01-01

    Full Text Available Shale gas is an effective gas resource all over the world. The evaluation of pore structure plays a critical role in exploring shale gas efficiently. Nitrogen adsorption experiment is one of the significant approaches to analyze pore size structure of shale. Shale is extremely heterogeneous due to component diversity and structure complexity. Therefore, adsorption isotherms for homogeneous adsorbents and empirical isotherms may not apply to shale. The shape of adsorption-desorption curve indicates that nitrogen adsorption on shale includes monolayer adsorption, multilayer adsorption, and capillary condensation. Usually, Langmuir isotherm is a monolayer adsorption model for ideal interfaces; BET (Brunauer, Emmett, Teller adsorption isotherm is a multilayer adsorption model based on specific assumptions; Freundlich isotherm is an empirical equation widely applied in liquid phase adsorption. In this study, a new nitrogen adsorption isotherm is applied to simultaneously depict monolayer adsorption, multilayer adsorption, and capillary condensation, which provides more real and accurate representation of nitrogen adsorption on shale. In addition, parameters are discussed in relation to heat of adsorption which is relevant to the shape of the adsorption isotherm curve. The curve fitting results indicate that our new nitrogen adsorption isotherm can appropriately describe the whole process of nitrogen adsorption on shale.

  12. Intravascular enhancement with identical iodine delivery rate using different iodine contrast media in a circulation phantom.

    Science.gov (United States)

    Mihl, Casper; Wildberger, Joachim E; Jurencak, Tomas; Yanniello, Michael J; Nijssen, Estelle C; Kalafut, John F; Nalbantov, Georgi; Mühlenbruch, Georg; Behrendt, Florian F; Das, Marco

    2013-11-01

    Both iodine delivery rate (IDR) and iodine concentration are decisive factors for vascular enhancement in computed tomographic angiography. It is unclear, however, whether the use of high-iodine concentration contrast media is beneficial to lower iodine concentrations when IDR is kept identical. This study evaluates the effect of using different iodine concentrations on intravascular attenuation in a circulation phantom while maintaining a constant IDR. A circulation phantom with a low-pressure venous compartment and a high-pressure arterial compartment simulating physiological circulation parameters was used (heart rate, 60 beats per minute; stroke volume, 60 mL; blood pressure, 120/80 mm Hg). Maintaining a constant IDR (2.0 g/s) and a constant total iodine load (20 g), prewarmed (37°C) contrast media with differing iodine concentrations (240-400 mg/mL) were injected into the phantom using a double-headed power injector. Serial computed tomographic scans at the level of the ascending aorta (AA), the descending aorta (DA), and the left main coronary artery (LM) were obtained. Total amount of contrast volume (milliliters), iodine delivery (grams of iodine), peak flow rate (milliliter per second), and intravascular pressure (pounds per square inch) were monitored using a dedicated data acquisition program. Attenuation values in the AA, the DA, and the LM were constantly measured (Hounsfield unit [HU]). In addition, time-enhancement curves, aortic peak enhancement, and time to peak were determined. All contrast injection protocols resulted in similar attenuation values: the AA (516 [11] to 531 [37] HU), the DA (514 [17] to 531 [32] HU), and the LM (490 [10] to 507 [17] HU). No significant differences were found between the AA, the DA, and the LM for either peak enhancement (all P > 0.05) or mean time to peak (AA, 19.4 [0.58] to 20.1 [1.05] seconds; DA, 21.1 [1.0] to 21.4 [1.15] seconds; LM, 19.8 [0.58] to 20.1 [1.05] seconds). This phantom study demonstrates that

  13. The placenta as a compensatory iodine storage organ.

    LENUS (Irish Health Repository)

    Burns, Robert

    2011-05-01

    The production of iodine-containing thyroid hormones necessary for brain development in the fetus depends not only on maternal dietary intake but also on placental iodine transport. The optimum level of iodine nutrition during pregnancy and the proportion of the pregnant population reaching this level have previously been evaluated. Little information exists on the ability of the placenta to either accumulate or store iodine. This study aims to investigate iodine uptake and tissue iodine content within placental tissue obtained from women delivering at term.

  14. Effects of Increased Iodine Intake on Thyroid Disorders

    Directory of Open Access Journals (Sweden)

    Xin Sun

    2014-09-01

    Full Text Available Iodine is a micronutrient essential for the production of thyroid hormones. Iodine deficiency is the most common cause of preventable mental impairment worldwide. Universal salt iodization (USI has been introduced in many countries as a cost-effective and sustainable way to eliminate iodine deficiency disorders for more than 25 years. Currently, the relationship between USI and iodine excess has attracted more attention. Iodine excess can lead to hypothyroidism and autoimmune thyroiditis, especially for susceptible populations with recurring thyroid disease, the elderly, fetuses, and neonates. Nationwide USI was introduced in China in 1996. This review focused on the effects of iodine excess worldwide and particularly in China.

  15. [Application of iodine metabolism analysis methods in thyroid diseases].

    Science.gov (United States)

    Han, Jian-hua; Qiu, Ling

    2013-08-01

    The main physiological role of iodine in the body is to synthesize thyroid hormone. Both iodine deficiency and iodine excess can lead to severe thyroid diseases. While its role in thyroid diseases has increasingly been recognized, few relevant platforms and techniques for iodine detection have been available in China. This paper summarizes the advantages and disadvantages of currently iodine detection methods including direct titration, arsenic cerium catalytic spectrophotometry, chromatography with pulsed amperometry, colorimetry based on automatic biochemistry, inductively coupled plasma mass spectrometry, so as to optimize the iodine nutrition for patients with thyroid diseases.

  16. Acidic gases (CO{sub 2}, NO{sub 2} and SO{sub 2}) capture and dissociation on metal decorated phosphorene

    Energy Technology Data Exchange (ETDEWEB)

    Kuang, Anlong, E-mail: alkuang@swu.edu.cn [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Kuang, Minquan; Yuan, Hongkuan; Wang, Guangzhao; Chen, Hong [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Yang, Xiaolan [School of Materials Science and Engineering, Beihang University, Beijing 100191 (China)

    2017-07-15

    Highlights: • The light metal decorated phosphorene sheets are very effective for capture of CO{sub 2}, NO{sub 2} and SO{sub 2} because of large adsorption energies. • The adsorption energy is obviously dependent on the amount of electrons transferred between acidic gases and metal decorated phosphorene. • Pt-decorated phosphorene can effectively catalyze the dissociation of acidic gas. - Abstract: Density functional theory is employed to investigate the adsorption and dissociation of several acidic gases (CO{sub 2}, NO{sub 2} and SO{sub 2}) on metal (Li, Al, Ni and Pt) decorated phosphorene. The results show that light metal (Li, Al) decorated phosphorene exhibits a strong adsorption of acidic gases, i.e., the adsorption energy of CO{sub 2} on Li decorated phosphorene is 0.376 eV which is the largest in all adsorption of CO{sub 2} on metal decorated phosphorene and Al decorated phosphorene is most effective for capture of NO{sub 2} and SO{sub 2} due to large adsorption energies of 3.951 and 3.608 eV, respectively. Moreover, Li and Al light metals have stronger economic effectiveness and more friendly environment compared with the transition metals, the strong adsorption ability of acidic gases and low price suggest that Li, Al decorated phosphorene may be useful and promising for collection and filtration of exhaust gases. The reaction energy barriers of acidic gases dissociated process on Pt decorated phosphorene are relatively low and the reaction processes are significantly exothermic, indicating that the dissociation process is favorable.

  17. 40 CFR 415.430 - Applicability; description of the iodine production subcategory.

    Science.gov (United States)

    2010-07-01

    ... iodine production subcategory. 415.430 Section 415.430 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Iodine Production Subcategory § 415.430 Applicability; description of the iodine production... iodine. ...

  18. Mixed-layered bismuth-oxygen-iodine materials for capture and waste disposal of radioactive iodine

    Science.gov (United States)

    Krumhansl, James L; Nenoff, Tina M

    2013-02-26

    Materials and methods of synthesizing mixed-layered bismuth oxy-iodine materials, which can be synthesized in the presence of aqueous radioactive iodine species found in caustic solutions (e.g. NaOH or KOH). This technology provides a one-step process for both iodine sequestration and storage from nuclear fuel cycles. It results in materials that will be durable for repository conditions much like those found in Waste Isolation Pilot Plant (WIPP) and estimated for Yucca Mountain (YMP). By controlled reactant concentrations, optimized compositions of these mixed-layered bismuth oxy-iodine inorganic materials are produced that have both a high iodine weight percentage and a low solubility in groundwater environments.

  19. Mixed-layered bismuth--oxygen--iodine materials for capture and waste disposal of radioactive iodine

    Science.gov (United States)

    Krumhansl, James L; Nenoff, Tina M

    2015-01-06

    Materials and methods of synthesizing mixed-layered bismuth oxy-iodine materials, which can be synthesized in the presence of aqueous radioactive iodine species found in caustic solutions (e.g. NaOH or KOH). This technology provides a one-step process for both iodine sequestration and storage from nuclear fuel cycles. It results in materials that will be durable for repository conditions much like those found in Waste Isolation Pilot Plant (WIPP) and estimated for Yucca Mountain (YMP). By controlled reactant concentrations, optimized compositions of these mixed-layered bismuth oxy-iodine inorganic materials are produced that have both a high iodine weight percentage and a low solubility in groundwater environments.

  20. Controlling Chemical Reactions in Confined Environments: Water Dissociation in MOF-74

    Directory of Open Access Journals (Sweden)

    Erika M. A. Fuentes-Fernandez

    2018-02-01

    Full Text Available The confined porous environment of metal organic frameworks (MOFs is an attractive system for studying reaction mechanisms. Compared to flat oxide surfaces, MOFs have the key advantage that they exhibit a well-defined structure and present significantly fewer challenges in experimental characterization. As an example of an important reaction, we study here the dissociation of water—which plays a critical role in biology, chemistry, and materials science—in MOFs and show how the knowledge of the structure in this confined environment allows for an unprecedented level of understanding and control. In particular, combining in-situ infrared spectroscopy and first-principles calculations, we show that the water dissociation reaction can be selectively controlled inside Zn-MOF-74 by alcohol, through both chemical and physical interactions. Methanol is observed to speed up water dissociation by 25% to 100%, depending on the alcohol partial pressure. On the other hand, co-adsorption of isopropanol reduces the speed of the water reaction, due mostly to steric interactions. In addition, we also investigate the stability of the product state after the water dissociation has occurred and find that the presence of additional water significantly stabilizes the dissociated state. Our results show that precise control of reactions within nano-porous materials is possible, opening the way for advances in fields ranging from catalysis to electrochemistry and sensors.

  1. Diffractive dissociation and new quarks

    International Nuclear Information System (INIS)

    White, A.R.

    1983-04-01

    We argue that the chiral limit of QCD can be identified with the strong (diffractive dissociation) coupling limit of reggeon field theory. Critical Pomeron scaling at high energy must then be directly related to an infra-red fixed-point of massless QCD and so requires a large number of flavors. This gives a direct argument that the emergence of diffraction-peak scaling, KNO scaling etc. at anti p-p colliders are evidence of a substantial quark structure still to be discovered

  2. Active molecular iodine photochemistry in the Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Raso, Angela R.; Custard, Kyle D.; May, Nathaniel W.; Tanner, David; Newburn, Matthew K.; Walker, Lawrence R.; Moore, Ronald J.; Huey, L. G.; Alexander, Lizabeth; Shepson, Paul B.; Pratt, Kerri A.

    2017-09-05

    During springtime, the Arctic atmospheric boundary layer undergoes frequent rapid depletions in ozone and gaseous elemental mercury due to reactions with halogen atoms, influencing atmospheric composition and pollutant fate. Although bromine chemistry has been shown to initiate ozone depletion events, and it has long been hypothesized that iodine chemistry may contribute, no previous measurements of molecular iodine (I2) have been reported in the Arctic. Iodine chemistry also contributes to atmospheric new particle formation and therefore cloud properties and radiative forcing. Here we present Arctic atmospheric I2 and snowpack iodide (I-) measurements, which were conducted near Utqiagvik, AK, in February 2014. Using chemical ionization mass spectrometry, I2 was observed in the atmosphere at mole ratios of 0.3–1.0 ppt, and in the snowpack interstitial air at mole ratios up to 22 ppt under natural sunlit conditions and up to 35 ppt when the snowpack surface was artificially irradiated, suggesting a photochemical production mechanism. Further, snow meltwater I-measurements showed enrichments of up to ~1,900 times above the seawater ratio of I-/Na+, consistent with iodine activation and recycling. Modeling shows that observed I2 levels are able to significantly increase ozone depletion rates, while also producing iodine monoxide (IO) at levels recently observed in the Arctic. These results emphasize the significance of iodine chemistry and the role of snowpack photochemistry in Arctic atmospheric composition, and imply that I2 is likely a dominant source of iodine atoms in the Arctic.

  3. Experimentally-induced dissociation impairs visual memory.

    Science.gov (United States)

    Brewin, Chris R; Mersaditabari, Niloufar

    2013-12-01

    Dissociation is a phenomenon common in a number of psychological disorders and has been frequently suggested to impair memory for traumatic events. In this study we explored the effects of dissociation on visual memory. A dissociative state was induced experimentally using a mirror-gazing task and its short-term effects on memory performance were investigated. Sixty healthy individuals took part in the experiment. Induced dissociation impaired visual memory performance relative to a control condition; however, the degree of dissociation was not associated with lower memory scores in the experimental group. The results have theoretical and practical implications for individuals who experience frequent dissociative states such as patients with posttraumatic stress disorder (PTSD). Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Iodine concentration in cow's milk and its relation with urinary iodine concentrations in the population.

    Science.gov (United States)

    Soriguer, Federico; Gutierrez-Repiso, Carolina; Gonzalez-Romero, Stella; Olveira, Gabriel; Garriga, Maria J; Velasco, Ines; Santiago, Piedad; de Escobar, Gabriella M; Garcia-Fuentes, Eduardo

    2011-02-01

    The importance of milk intake to the supply of dietary iodine is not fully known. We therefore undertook a study in Spain of the iodine concentration in cow's milk and the impact of the frequency of milk consumption on urinary iodine concentrations in three study populations. We studied the iodine concentration in 362 samples of milk from 45 commercial brands and compared it with the milk iodine status in studies undertaken 17 years earlier. The epidemiologic studies were performed in three different places in the south of Spain: two in school-age children (N = 757 and N = 1205 children) and one in adults (N = 1051). A milk consumption questionnaire was given and urinary iodine concentrations measured. The mean concentration of iodine in the milk rose from 1991 (117 ± 37 μg/L) to 2008 (259 ± 58 μg/L) (P milk (273 ± 52 μg/L) than in semi-skimmed milk (254 ± 57 μg/L) or whole milk (251 ± 61 μg/L) (P milk. The urinary iodine concentrations in all three epidemiologic studies were significantly associated with the frequency of milk intake. The concentration of iodine in cow's milk has risen over recent years, and it is higher in skimmed milk. The results also show that cow's milk is a relevant source of dietary iodine. Copyright © 2010 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  5. H2 adsorption on free and graphene-supported Ni nanoclusters: A theoretical study

    Science.gov (United States)

    Farmanzadeh, Davood; Abdollahi, Tahereh

    2018-02-01

    Density functional theory (DFT) was used to investigate the applicability of the graphene-supported Nin nanoclusters as catalysts for the hydrogenation reaction. The adsorption and complete dissociation of the H2 on the Nin nanoclusters were investigated at the PBE-G/DNP level of theory. Accordingly, molecularly and dissociatively adsorbed hydrogens were seen on the Nin (n = 2-3) and Nin (n = 4-10) nanoclusters, respectively. The hydrogen adsorption on the Ni6 and Ni4 nanoclusters were more effective than other nanoclusters. Therefore, we investigated the hydrogen adsorption on the graphene-supported Ni2, Ni4 and Ni6 nanoclusters. The nanocluster adsorption energy on the graphene increased with the number of atoms in the nanocluster, whereas the adsorption energy per atom decreased. Hence, due to the stronger interactions of Ni-Ni than those of Ni-C, it seemed that the formation of nanoclusters on the graphene surface was favorable over the dispersion of the separate atoms. The results confirmed that the H2 was dissociatively adsorbed on the graphene-supported Ni4 and Ni6 nanoclusters, which can make them good candidates as catalysts.

  6. Competitive Protein Adsorption - Multilayer Adsorption and Surface Induced Protein Aggregation

    DEFF Research Database (Denmark)

    Holmberg, Maria; Hou, Xiaolin

    2009-01-01

    and that the outcome of IgG adsorption is much more sensitive to surface characteristics than the outcome of albumin adsorption. Using high concentrations of protein solution and hydrophobic polymer surfaces during adsorption can induce IgG aggregation, which is observed as extremely high IgG adsorptions. Besides......In this study, competitive adsorption of albumin and IgG (immunoglobulin G) from human serum solutions and protein mixtures onto polymer surfaces is studied by means of radioactive labeling. By using two different radiolabels (125I and 131I), albumin and IgG adsorption to polymer surfaces...... is monitored simultaneously and the influence from the presence of other human serum proteins on albumin and IgG adsorption, as well as their mutual influence during adsorption processes, is investigated. Exploring protein adsorption by combining analysis of competitive adsorption from complex solutions...

  7. Mirror Writing and a Dissociative Identity Disorder

    OpenAIRE

    Le, Catherine; Smith, Joyce; Cohen, Lewis

    2009-01-01

    Individuals with dissociative identity disorder (DID) have been known to show varied skills and talents as they change from one dissociative state to another. For example, case reports have described people who have changed their handedness or have spoken foreign languages during their dissociative states. During an interview with a patient with DID, a surprising talent emerged when she wrote a sentence for the Folstein Mini-Mental State Exam—mirror writing. It is not known whether her mirror...

  8. The adsorption of nitrogen oxides on crystalline ice

    Directory of Open Access Journals (Sweden)

    T. Bartels

    2002-01-01

    Full Text Available The partitioning of nitrogen oxides between ice and air is of importance to the ozone budget in the upper troposphere. In the present study, adsorption of nitrogen oxides on ice was investigated at atmospheric pressure using a chromatographic technique with radioactively labelled nitrogen oxides at low concentrations. The measured retentions solely depended on molecular adsorption and were not influenced by dimerisation, formation of encapsulated hydrates on the ice surface, dissociation of the acids, nor by migration into a quasi-liquid layer or grain boundaries. Based on the chromatographic retention and the model of thermo-chromatography, the standard adsorption enthalpy of -20 kJ mol-1 for NO, -22kJ mol-1 for NO2, -30kJ mol-1 for peroxyacetyl nitrate, -32kJ mol-1 for HON} and -44 kJ mol-1 for HNO3 was calculated. To perform those calculations within the model of thermo-chromatography, the standard adsorption entropy was calculated based on statistical thermodynamics. In this work, two different choices of standard states were applied, and consequently different values of the standard adsorption entropy, of either between -39 kJ mol-1 and -45kJ mol-1, or -164 kJ mol-1 and -169 kJ mol-1 for each nitrogen oxide were derived. The standard adsorption enthalpy was identical for both standard adsorption entropies and thus shown to be independent of the choice of standard state. A brief outlook on environmental implications of our findings indicates that adsorption on ice might be an important removal process of HNO3. In addition, it might be of some importance for HONO and peroxyacetyl nitrate and irrelevant for NO and NO2.

  9. The kinetic study of oxidation of iodine by hydrogen peroxide

    International Nuclear Information System (INIS)

    Cantrel, L.; Chopin, J.

    1996-01-01

    Iodine chemistry is one of the most important subjects of research in the field of reactor safety because this element can form volatile species which represent a biological hazard for environment. As the iodine and the peroxide are both present in the sump of the containment in the event of a severe accident on a light water nuclear reactor, it can be important to improve the knowledge on the reaction of oxidation of iodine by hydrogen peroxide. The kinetics of iodine by hydrogen peroxide has been studied in acid solution using two different analytical methods. The first is a UV/Vis spectrophotometer which records the transmitted intensity at 460 nm as a function of time to follow the decrease of iodine concentration, the second is an amperometric method which permits to record the increase of iodine+1 with time thanks to the current of reduction of iodine+1 to molecular iodine. The iodine was generated by Dushman reaction and the series of investigations were made at 40 o C in a continuous stirring tank reactor. The influence of the initial concentrations of iodine, iodate, hydrogen peroxide, H + ions has been determined. The kinetics curves comprise two distinct chemical phases both for molecular iodine and for iodine+1. The relative importance of the two processes is connected to the initial concentrations of [I 2 ], [IO 3 - ], [H 2 O 2 ] and [H + ]. A rate law has been determined for the two steps for molecular iodine. (author) figs., tabs., 22 refs

  10. [Iodine and thyroid gland with or without nuclear catastrophe].

    Science.gov (United States)

    Dilas, Ljiljana Todorović; Bajkin, Ivana; Icin, Tijana; Paro, Jovanka Novaković; Zavisić, Branka Kovacev

    2012-01-01

    Iodine, as a trace element, is a necessary and limiting substrate for thyroid gland hormone synthesis. It is an essential element that enables the thyroid gland to produce thyroid hormones thyroxine (T4) and triiodothyronine (T3). Synthesis of Thyroid Hormones and Iodine Metabolism. Three iodine molecules are added to make triiodothyronine, and four for thyroxine - the two key hormones produced by the thyroid gland. Iodine deficiency The proper daily amount of iodine is required for optimal thyroid function. Iodine deficiency can cause hypothyroidism, developmental brain disorders and goiter. Iodine deficiency is the single most common cause of preventable mental retardation and brain damage in the world. It also decreases child survival, causes goiters, and impairs growth and development. Iodine deficiency disorders in pregnant women cause miscarriages, stillbirths, and other complications. Children with iodine deficiency disorders can grow up stunted, apathetic, mentally retarded, and incapable of normal movements, speech or hearing. Excessive Iodine Intake. Excessive iodine intake, which can trigger a utoimmune thyroid disease and dysfunction. is on the other side. Iodine use in Case of Nuclear Catastrophe. In addition to other severe consuquences of radioactivity, high amount of radioactive iodine causes significant increase in incidence of thyroid gland carcinoma after some of the nuclear catastrophes (Hiroshima, Nagasaki, Chernobyl, Fukushima). The incidence of thyroid carcinoma was increased mostly in children. This paper was aimed at clarifying some of the possibilities of prevention according to the recommendations given by the World Health Organization.

  11. Mirror writing and a dissociative identity disorder.

    Science.gov (United States)

    Le, Catherine; Smith, Joyce; Cohen, Lewis

    2009-01-01

    Individuals with dissociative identity disorder (DID) have been known to show varied skills and talents as they change from one dissociative state to another. For example, case reports have described people who have changed their handedness or have spoken foreign languages during their dissociative states. During an interview with a patient with DID, a surprising talent emerged when she wrote a sentence for the Folstein Mini-Mental State Exam-mirror writing. It is not known whether her mirror writing had a deeper level of meaning; however, it does emphasize the idiosyncratic nature of dissociative identity disorder.

  12. Mirror Writing and a Dissociative Identity Disorder

    Directory of Open Access Journals (Sweden)

    Catherine Le

    2009-01-01

    Full Text Available Individuals with dissociative identity disorder (DID have been known to show varied skills and talents as they change from one dissociative state to another. For example, case reports have described people who have changed their handedness or have spoken foreign languages during their dissociative states. During an interview with a patient with DID, a surprising talent emerged when she wrote a sentence for the Folstein Mini-Mental State Exam—mirror writing. It is not known whether her mirror writing had a deeper level of meaning; however, it does emphasize the idiosyncratic nature of dissociative identity disorder.

  13. Biofortification of lettuce (Lactuca sativa L.) with iodine: The effect of iodine form and concentration in the nutrient solution on growth, development and iodine uptake of lettuce grown in water culture

    NARCIS (Netherlands)

    Voogt, W.; Holwerda, H.T.; Khodabaks, M.R.

    2010-01-01

    BACKGROUND: Iodine is an essential trace element for humans. Two billion individuals have insufficient iodine intake. Biofortification of vegetables with iodine offers an excellent opportunity to increase iodine intake by humans. The main aim was to study the effect of iodine form and concentration

  14. Dissociative identity disorder: Medicolegal challenges.

    Science.gov (United States)

    Farrell, Helen M

    2011-01-01

    Persons with dissociative identity disorder (DID) often present in the criminal justice system rather than the mental health system and perplex experts in both professions. DID is a controversial diagnosis with important medicolegal implications. Defendants have claimed that they committed serious crimes, including rape or murder, while they were in a dissociated state. Asserting that their alter personality committed the bad act, defendants have pleaded not guilty by reason of insanity (NGRI). In such instances, forensic experts are asked to assess the defendant for DID and provide testimony in court. Debate continues over whether DID truly exists, whether expert testimony should be allowed into evidence, and whether it should exculpate defendants for their criminal acts. This article reviews historical and theoretical perspectives on DID, presents cases that illustrate the legal implications and controversies of raising an insanity defense based on multiple personalities, and examines the role of forensic experts asked to comment on DID with the goal of assisting clinicians in the medicolegal assessment of DID in relation to crimes.

  15. Norm - contaminated iodine production facilities decommissioning in Turkmenistan: experience and results

    Energy Technology Data Exchange (ETDEWEB)

    Gelbutovskiy, Alexander; Cheremisin, Peter; Egorov, Alexander; Troshev, Alexander; Boriskin, Mikhail [ECOMET-S, Saint Petersburg (Russian Federation)

    2013-07-01

    This report summarizes the data, including the cost parameters of the former iodine production facilities decommissioning project in Turkmenistan. Before the closure, these facilities were producing the iodine from the underground mineral water by the methods of charcoal adsorption. Balkanabat iodine and Khazar chemical plants' sites remediation, transportation and disposal campaigns main results could be seen. The rehabilitated area covers 47.5 thousand square meters. The remediation equipment main characteristics, technical solutions and rehabilitation operations performed are indicated also. The report shows the types of the waste shipping containers, the quantity and nature of the logistics operations. The project waste turnover is about 2 million ton-kilometers. The problems encountered during the remediation of the Khazar chemical plant site are discussed: undetected waste quantities that were discovered during the operational activities required the additional volume of the disposal facility. The additional repository wall superstructure was designed and erected to accommodate this additional waste. There are data on the volume and characteristics of the NORM waste disposed: 60.4 thousand cu.m. of NORM with total activity 1 439 x 10{sup 9} Bq (38.89 Ci) were disposed at all. This report summarizes the project implementation results, from 2009 to 15.02.2012 (the date of the repository closure and its placement under the controlled supervision), including monitoring results within a year after the repository closure. (authors)

  16. A 3D Covalent Organic Framework with Exceptionally High Iodine Capture Capability.

    Science.gov (United States)

    Wang, Chang; Wang, Yu; Ge, Rile; Song, Xuedan; Xing, Xueqing; Jiang, Qike; Lu, Hui; Hao, Ce; Guo, Xinwen; Gao, Yanan; Jiang, Donglin

    2018-01-12

    Using porous materials to cope with environmental issues is promising but remains a challenge especially for removing the radioactive vapor wastes in fission because of harsh adsorption conditions. Here we report a new, stable covalent organic framework (COF) as a porous platform for removing iodine vapor-a major radioactive fission waste. The three-dimensional COF consists of a diamond topology knotted by adamantane units, creates ordered one-dimensional pores and are highly porous. The COF enables the removal of iodine vapor via charge transfer complex formation with the pore walls to achieve exceptional capacity. Moreover, the 3D COF is "soft" to trigger structural fitting to iodine while retaining connectivity and enables cycle use for many times while retaining high uptake capacity. These results set a new benchmark for fission waste removal and suggest the great potential of COFs as a designable porous material for challenging world-threatening pollution issues. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Persistence of goiter despite adequate iodine intake

    International Nuclear Information System (INIS)

    Aminzadeh, M.; Karamizadeh, Z.; Amirhakimi, G.H.

    2007-01-01

    To evaluate the state of iodine uptake and frequency of goiter in a previously endemic population after use of iodine salt for ten years. In an area in south of Iran following examination of randomly selected 1504, 8-10 year school children, 102 cases with grade 2 or larger goiter were found. One hundred normal cases regarding thyroid examination were also selected as controls. From all 202 children, random urine specimen was assayed for iodine as an indicator of iodide intake. Frequency of goiter grade 2 or larger was 6.8%. Median levels of urinary iodine in goiterous children and controls were 20.00 micro gram/dL and 24.50 micro gram/dL respectively. Values more than 10 micro g/dL indicate sufficient intake. Frequency of iodine deficiency in patients with goiter was 14.0% vs. 12.7% in control group. There was no statistically significant difference between the two groups (P value=0.748). Iodized salt has been effective to provide acceptable iodide intake but other causes are supposed to be responsible as etiologic factors for persistence of endemic goiter. (author)

  18. Co adsorption in kaolinite

    International Nuclear Information System (INIS)

    Souza, Eliel S.; Silva, Paulo S.C.

    2017-01-01

    Adsorption of metal ions in clay minerals has been used as an alternative to water and effluents treatment. Kaolinite is a clay mineral that presents low specific surface area and exchange ion capacity. Nevertheless, structural modifications can be achieved by means of acid or thermal activation. In this paper, it was studied the surface area of kaolinite/bentonite, kaolinite/activated carbon mixtures, thermal activated kaolinite and thermal activated kaolinite/activated carbon mixture. The mixture of kaolinite/activated carbon was tested for pH, contact time, interfering ions and initial concentration effects in the cobalt adsorption. Results showed that the optimized parameters are pH 6 and contact time of 30 min. Chromium acted as a competitive ion, zinc does not appear to have affected adsorption while iron seems to have favored it. Langmuir and Freundlich isotherms indicated that the adsorption of Co in the mixture of kaolinite/activated carbon is a spontaneous process. (author)

  19. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T [Huntington Beach, CA; Sahimi, Muhammad [Altadena, CA; Fayyaz-Najafi, Babak [Richmond, CA; Harale, Aadesh [Los Angeles, CA; Park, Byoung-Gi [Yeosu, KR; Liu, Paul K. T. [Lafayette Hill, PA

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  20. Co adsorption in kaolinite

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Eliel S.; Silva, Paulo S.C., E-mail: eliel201019@hotmail.com, E-mail: pscsilva@ipen.br [Instituto de Pesquisas Energética s e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    Adsorption of metal ions in clay minerals has been used as an alternative to water and effluents treatment. Kaolinite is a clay mineral that presents low specific surface area and exchange ion capacity. Nevertheless, structural modifications can be achieved by means of acid or thermal activation. In this paper, it was studied the surface area of kaolinite/bentonite, kaolinite/activated carbon mixtures, thermal activated kaolinite and thermal activated kaolinite/activated carbon mixture. The mixture of kaolinite/activated carbon was tested for pH, contact time, interfering ions and initial concentration effects in the cobalt adsorption. Results showed that the optimized parameters are pH 6 and contact time of 30 min. Chromium acted as a competitive ion, zinc does not appear to have affected adsorption while iron seems to have favored it. Langmuir and Freundlich isotherms indicated that the adsorption of Co in the mixture of kaolinite/activated carbon is a spontaneous process. (author)

  1. Dissociative symptoms and dissociative disorder comorbidity in patients with obsessive-compulsive disorder.

    Science.gov (United States)

    Belli, Hasan; Ural, Cenk; Vardar, Melek Kanarya; Yesılyurt, Sema; Oncu, Fatıh

    2012-10-01

    The present study attempted to assess the dissociative symptoms and overall dissociative disorder comorbidity in patients with obsessive-compulsive disorder (OCD). In addition, we examined the relationship between the severity of obsessive-compulsive symptoms and dissociative symptoms. All patients admitted for the first time to the psychiatric outpatient unit were included in the study. Seventy-eight patients had been diagnosed as having OCD during the 2-year study period. Patients had to meet the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for OCD. Most (76.9%; n = 60) of the patients were female, and 23.1% (n = 18) of the patients were male. Dissociation Questionnaire was used to measure dissociative symptoms. The Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Dissociative Disorders interviews and Yale-Brown Obsessive Compulsive Checklist and Severity Scale were used. Eleven (14%) of the patients with OCD had comorbid dissociative disorder. The most prevalent disorder in our study was dissociative depersonalization disorder. Dissociative amnesia and dissociative identity disorder were common as well. The mean Yale-Brown score was 23.37 ± 7.27 points. Dissociation Questionnaire scores were between 0.40 and 3.87 points, and the mean was 2.23 ± 0.76 points. There was a statistically significant positive correlation between Yale-Brown points and Dissociation Questionnaire points. We conclude that dissociative symptoms among patients with OCD should alert clinicians for the presence of a chronic and complex dissociative disorder. Clinicians may overlook an underlying dissociative process in patients who have severe symptoms of OCD. However, a lack of adequate response to cognitive-behavioral and drug therapy may be a consequence of dissociative process. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Iodine intake as a determinant of thyroid disorders in populations

    DEFF Research Database (Denmark)

    Laurberg, Peter; Cerqueira, Charlotte; Ovesen, Lars

    2010-01-01

    Depending on the availability of iodine, the thyroid gland is able to enhance or limit the use of iodine for thyroid hormone production. When compensation fails, as in severely iodine-deficient populations, hypothyroidism and developmental brain damage will be the dominating disorders. This is, out...... and mortality. Conclusion: Even minor differences in iodine intake between populations are associated with differences in the occurrence of thyroid disorders. Both iodine intake levels below and above the recommended interval are associated with an increase in the risk of disease in the population. Optimally......, iodine intake of a population should be kept within a relatively narrow interval where iodine deficiency disorders are prevented, but not higher. Monitoring and adjusting of iodine intake in a population is an important part of preventive medicine....

  3. Comprehensive handbook of iodine: nutritional, biochemical, pathological and therapeutic aspects

    National Research Council Canada - National Science Library

    Preedy, Victor R; Burrow, Gerard N; Watson, Ronald R

    2009-01-01

    ... for Monitoring Effects of Iodine/Thyroid Status in Populations Inge Bülow Pedersen and Peter Laurberg 3 15 29 39 47 55 65 Section 2: General Aspects of Iodine Sources and Intakes in the Diet, Mai...

  4. Iodine Hall Thruster for Space Exploration, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In the Phase I program, Busek Co. Inc. tested an existing Hall thruster, the BHT-8000, on iodine propellant. The thruster was fed by a high flow iodine feed system,...

  5. Chemical template directed iodine patterns on the octadecyltrichlorosilane surface.

    Science.gov (United States)

    Cai, Yuguang

    2008-01-01

    A carboxylic-terminated nanometer-scale chemical pattern on an octadecyltrichlorosilane (OTS) surface can guide the deposition and crystallization of iodine, forming an iodine pattern on the chemical pattern. The iodine in the pattern is gel-like when fabricated by the solution-deposit method. In contrast, a dendritic, snowflake-shaped polycrystalline iodine sheet is formed by the vapor-phase condensation method. The data demonstrate that iodine is a good tracing and visualizing agent for studying liquid behavior at the nano scale. The topography of the iodine stain reveals that the "coffee ring" effect can be suppressed by reducing the pattern size and increasing the evaporation rate. The chemical template-bound iodine pattern has an unusually low vapor pressure and it can withstand prolonged baking at elevated temperature, which differs significantly from bulk iodine crystals.

  6. From dissociation to trauma? Individual differences in dissociation as predictor of 'trauma' perception

    NARCIS (Netherlands)

    Rassin, Eric; van Rootselaar, Anne-Fleur

    2006-01-01

    In clinical literature, dissociative complaints are generally considered to be the result of traumatic experiences. However, it has been argued that dissociative complaints, in turn, may indulge over-reporting of traumatic experiences. Hence, correlations between dissociation and self-reported

  7. Dissociation in patients with dissociative seizures: relationships with trauma and seizure symptoms.

    Science.gov (United States)

    Pick, S; Mellers, J D C; Goldstein, L H

    2017-05-01

    This study aimed to extend the current understanding of dissociative symptoms experienced by patients with dissociative (psychogenic, non-epileptic) seizures (DS), including psychological and somatoform types of symptomatology. An additional aim was to assess possible relationships between dissociation, traumatic experiences, post-traumatic symptoms and seizure manifestations in this group. A total of 40 patients with DS were compared with a healthy control group (n = 43), matched on relevant demographic characteristics. Participants completed several self-report questionnaires, including the Multiscale Dissociation Inventory (MDI), Somatoform Dissociation Questionnaire-20, Traumatic Experiences Checklist and the Post-Traumatic Diagnostic Scale. Measures of seizure symptoms and current emotional distress (Hospital Anxiety and Depression Scale) were also administered. The clinical group reported significantly more psychological and somatoform dissociative symptoms, trauma, perceived impact of trauma, and post-traumatic symptoms than controls. Some dissociative symptoms (i.e. MDI disengagement, MDI depersonalization, MDI derealization, MDI memory disturbance, and somatoform dissociation scores) were elevated even after controlling for emotional distress; MDI depersonalization scores correlated positively with trauma scores while seizure symptoms correlated with MDI depersonalization, derealization and identity dissociation scores. Exploratory analyses indicated that somatoform dissociation specifically mediated the relationship between reported sexual abuse and DS diagnosis, along with depressive symptoms. A range of psychological and somatoform dissociative symptoms, traumatic experiences and post-traumatic symptoms are elevated in patients with DS relative to healthy controls, and seem related to seizure manifestations. Further studies are needed to explore peri-ictal dissociative experiences in more detail.

  8. Iodine Intakes of Victorian Schoolchildren Measured Using 24-h Urinary Iodine Excretion

    Directory of Open Access Journals (Sweden)

    Kelsey Beckford

    2017-08-01

    Full Text Available Mandatory fortification of bread with iodized salt was introduced in Australia in 2009, and studies using spot urine collections conducted post fortification indicate that Australian schoolchildren are now replete. However an accurate estimate of daily iodine intake utilizing 24-h urinary iodine excretion (UIE μg/day has not been reported and compared to the estimated average requirement (EAR. This study aimed to assess daily total iodine intake and status of a sample of primary schoolchildren using 24-h urine samples. Victorian primary school children provided 24-h urine samples between 2011 and 2013, from which urinary iodine concentration (UIC, μg/L and total iodine excretion (UIE, μg/day as an estimate of intake was determined. Valid 24-h urine samples were provided by 650 children, mean (SD age 9.3 (1.8 years (n = 359 boys. The mean UIE of 4–8 and 9–13 year olds was 94 (48 and 111 (57 μg/24-h, respectively, with 29% and 26% having a UIE below the age-specific EAR. The median (IQR UIC was 124 (83,172 μg/L, with 36% of participants having a UIC < 100 μg/L. This convenience sample of Victorian schoolchildren were found to be iodine replete, based on UIC and estimated iodine intakes derived from 24-h urine collections, confirming the findings of the Australian Health Survey.

  9. Adsorption Isotherms of Boron in Soil: the effects of Sodium Adsorption Ratio (SAR, pH and Ionic strength

    Directory of Open Access Journals (Sweden)

    Mojtaba Moqbeli

    2017-03-01

    solution after filtration, from added boron. Results and Discussion: The Langmuir isotherm waswell fitted to the adsorbtiondata based on the R2 and SEE.At different IS and SAR levels, the soil exhibited different adsorption behaviors. The effect of SAR on the boron adsorption was greater at high concentrations.The results showed the increase in sodium adsorption ratio,increased soil pH and Boron adsorption.An increase in sodium adsorption ratio up to 100 resulted in a small increase in Boron adsorption compared to SAR=20. With sodium adsorption ratio of 100, soil pHincreased from 8.3 to 8.7. At about PH=9.5, maximum adsorption occurs because boron dissociation is greater when pka = pH. Increasing ionic strength increased the boron adsorption; the absorption rate wasmuch higher at higher ionic strength.Model-predicted and experimental parameters obtained using the Langmuir equation pointed to the large effect of salt concentration on the boron adsorption which wasan increase of around 10% and 75% in q max as a result of an increase in salt concentration from 0.02 to 0.06 and 0.12 M respectively. We can ignore the effect ofsalt at very low equilibrium concentration; however, it increases gradually with increasing the equilibrium concentration of boron. Conclusions: The results of the present study showed that sodium adsorption ratio was low, in low equilibrium concentration related to low boron concentration, but the equilibrium concentration of boron increased with increasing the sodium adsorption ratio.In sodium adsorptionratio of 100, increasing pH increased the adsorption of boron. Boron adsorption was increased with increasing ionic strength; the adsorption rate was muchhigher than the rate of increase in ionic strength.Increasing the ionic strength suppresses the DDL on planar surface and therefore more negative borate ions are able to move close enough to interact with the adsorption sites located on the edge surfaces. Assuming that this phenomenon affects the

  10. Veganism as a cause of iodine deficient hypothyroidism.

    Science.gov (United States)

    Yeliosof, Olga; Silverman, Lawrence A

    2018-01-26

    Iodine deficiency is the most common cause of acquired hypothyroidism worldwide. Although uncommon in the Western world, the incidence of iodine deficiency may be rising due to the increased use of restrictive diets. We present a 23-month-old boy diagnosed with iodine deficiency hypothyroidism, induced by a vegan diet. This case highlights the risk for iodine deficiency in children on a vegan diet after discontinuation of breast/formula feeding that could lead to acquired hypothyroidism.

  11. Reaction rate of hydrolysis of iodine

    International Nuclear Information System (INIS)

    Miyake, Yoshikazu; Eguchi, Wataru; Adachi, Motonari

    1979-01-01

    Absorption rates of dilute iodine vapor contained in air by aqueous mixtures of sodium hydroxide and boric acid were measured using a laminar liquid jet column absorber at 298 K. Absorption rates in this system are controlled by a series of complex reactions taking place in the liquid phase. The reaction rate constant of iodine hydrolysis in the aqueous phase was determined from the absorption rates observed under the conditions that the base-catalytic hydrolysis reaction of iodine can be considered to be irreversible and that other reactions can be neglected. The absorption rates calculated theoretically with the rate constant value obtained above were in good accordance with the whole experimental data observed for a wide range of experimental conditions. (author)

  12. Prospects of the high power iodine laser

    International Nuclear Information System (INIS)

    Hohla, K.; Brederlow, G.; Fill, E.; Volk, R.; Witte, K.J.

    1976-09-01

    The characteristic properties of the iodine laser (gaseous laser substance, photolytic pump mechanism, variable stimulated emission cross-section) made it possible in a relatively short time to generate ns pulses in the kJ range. The Asterix II and III iodine laser systems at IPP are working successfully, and the question arises what prospects are afforded for further iodine laser development. What are the problems that have to be clarified in order to build 10 or 100 kJ systems for laser fusion experiments. According to our experience these can be classified as follows: 1) Short pulse generation and contrast ratio, 2) pulse shaping in a high-gain laser and amplification in the coherent time range, 3) non-linear properties at high intensities, 4) scalable pumping schemes and chemical processes. (orig./WL) [de

  13. Equilibrium adsorption of caffeic, chlorogenic and rosmarinic acids on cationic cross-linked starch with quaternary ammonium groups.

    Science.gov (United States)

    Simanaviciute, Deimante; Klimaviciute, Rima; Rutkaite, Ramune

    2017-02-01

    In the present study, the equilibrium adsorption of caffeic acid (CA) and its derivatives, namely, chlorogenic (CGA) and rosmarinic (RA) acids on cationic cross-linked starch (CCS) with degree of substitution of quaternary ammonium groups of 0.42 have been investigated in relation to the structure and acidity of phenolic acids. The Langmuir, Freundlich and Dubinin-Radushkevich adsorption models have been used to describe the equilibrium adsorption of CA, CGA and RA from their initial solutions and solutions having the equimolar amount of NaOH at different temperatures. In the case of adsorption from the initial solutions of acids the values of adsorption parameters were closely related to the dissociation constants of investigated acids. According to the increasing effectiveness of adsorption, phenolic acids could be arranged in the following order: CAacids solutions changed their sorption properties which became mostly related to the acids structure. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Rotational dissociation of impulsively aligned van der Waals complexes.

    Science.gov (United States)

    Søndergaard, Anders A; Zillich, Robert E; Stapelfeldt, Henrik

    2017-08-21

    The nonadiabatic alignment dynamics of weakly bound molecule-atom complexes, induced by a moderately intense 300 fs nonresonant laser pulse, is calculated by direct numerical solution of the time-dependent Schrödinger equation. Our method propagates the wave function according to the coupled channel equations for the complex, which can be done in a very efficient and stable manner out to large times. We present results for two van der Waal complexes, CS 2 -He and HCCH-He, as respective examples of linear molecules with large and small moments of inertia. Our main result is that at intensities typical of nonadiabatic alignment experiments, these complexes rapidly dissociate. In the case of the CS 2 -He complex, the ensuing rotational dynamics resembles that of isolated molecules, whereas for the HCCH-He complex, the detachment of the He atom severely perturbs and essentially quenches the subsequent rotational motion. At intensities of the laser pulse ≲2.0 × 10 12 W/cm 2 , it is shown that the molecule-He complex can rotate and align without breaking apart. We discuss the implications of our findings for recent experiments on iodine molecules solvated in helium nanodroplets.

  15. Iodine stability in salt double-fortified with iron and iodine.

    Science.gov (United States)

    Diosady, L L; Alberti, J O; Ramcharan, K; Mannar, M G Venkatesh

    2002-06-01

    Deficiencies in small quantities of micronutrients, especially iodine and iron, severely affect more than a third of the world's population, resulting in serious public health consequences, especially for women and young children. Salt is an ideal carrier of micronutrients. The double fortification of salt with both iodine and iron is an attractive approach to the reduction of both anemia and iodine-deficiency disorders. Because iodine is unstable under the storage conditions found during the manufacturing, distribution, and sale of salt in most developing countries, the effects of packaging materials and environmental conditions on the stability of salt double-fortified with iron and iodine were investigated. Salt was double-fortified with potassium iodide or potassium iodate and with ferrous sulfate or ferrous fumarate. The effects of stabilizers on the stability of iodine and iron were followed by storing the salt under three conditions that represent the extremes of normal distribution and sale for salt in developing countries: room temperature (25 degrees C) with 50%-70% relative humidity, 40 degrees C with 60% relative humidity, and 40 degrees C with 100% relative humidity. The effects of stabilizers, such as sodium hexametaphosphate (SHMP), calcium carbonate, calcium silicate, and dextrose were investigated. None of the combinations of iron and iodine compounds was stable at elevated temperatures. Essentially all of the iodine was lost over a period of six months. SHMP effectively slowed down the iodine loss, whereas magnesium chloride, a typical hygroscopic impurity, greatly accelerated this process. Calcium carbonate did not have a sparing effect on iodine, despite contrary indications in the literature. Ferrous sulfate-fortified salts generally turned yellow and developed an unpleasant rusty flavor. Salt fortified with ferrous fumarate and potassium, iodide was reasonably stable and maintained its organoleptic properties, making it more likely to be

  16. Development of Databases with Iodine in Foods and Dietary Supplements

    Science.gov (United States)

    Iodine is an essential micronutrient required for normal growth and development, thus an adequate intake of iodine is particularly important in pregnant and lactating women, and throughout childhood. Low levels of iodine in the soil and groundwater are common in many parts of the world, often leadi...

  17. Evaluating iodine deficiency in pregnant women and young infants

    DEFF Research Database (Denmark)

    Laurberg, Peter; Andersen, S.; Bjarnadottir, R. I.

    2007-01-01

    ) the concentration of iodine in a spot or casual urine sample cannot be used to diagnose iodine deficiency in an individual; 3) a moderate fall in the concentration of serum free T4 during pregnancy is not a sign of maternal iodine deficiency; 4) an increase in the concentration of serum thyroglobulin (Tg) during...

  18. Iodine Excess is a Risk Factor for Goiter Formation

    African Journals Online (AJOL)

    iodine deficiency. Although universal salt iodization in Uganda achieved a household coverage of 95% by 2005, goiter rates are still high. This study investigated the association between iodine excess and goiter. Methods: In a case control study, urinary iodine levels, complete blood count, T3, T4 and TSH levels were ...

  19. 129I Moessbauer spectroscopic study of metallocene-iodine adducts

    International Nuclear Information System (INIS)

    Nakashima, Satoru; Sakai, Hiroshi; Watanabe, Masanobu; Maeda, Yutaka

    1994-01-01

    A 129 I Moessbauer spectroscopic study of iodine adducts of ferrocenophane, biruthenocene, and osmocene is reported. The spectra show the existence of iodine bonded to the central metals of metallocenes in addition to triiodide anions. The valence state of iron in the ferrocenophane-iodine adduct is the same as those of ruthenium and osmium in their adducts. (orig.)

  20. Progress towards eliminating iodine deficiency in South Africa

    NARCIS (Netherlands)

    Jooste, P.; Zimmermann, M.B.

    2009-01-01

    Before the introduction of salt iodisation in 1954, South Africa was one of the many countries of the world with a lack of iodine in most of its territory and hence there was a need for a salt iodisation programme. The understanding of the iodine situation in South Africa, the basics of iodine

  1. Thyroid cancer in South Africa - an indicator of regional iodine ...

    African Journals Online (AJOL)

    Objective. Because follicular thyroid cancers predominate in iodine-deficient and papillary cancers predominate in iodine·replete populations. we have analysed national and regional (former Transvaal) incidences of these cancer types as a surrogate measure of the population iodine nutritional status in South Africa.

  2. Iodine Excess is a Risk Factor for Goiter Formation | Washington ...

    African Journals Online (AJOL)

    Iodine Excess is a Risk Factor for Goiter Formation. ... Iodine Excess is a Risk Factor for Goiter Formation. L Washington, T Makumbi, OJ Fualal, M Galukande. Abstract. Background: Goiters have been associated with iodine deficiency. Although universal salt iodization in Uganda achieved a household coverage of 95%

  3. Book review: Use of Stable Iodine in Nuclear Emergencies

    Directory of Open Access Journals (Sweden)

    Iraj Nabipour

    2011-11-01

    Full Text Available Following a radiological or nuclear event, radioactive iodine may be get into the body through respiratory or gastrointestinal systems. In the contaminated cases with radioactive iodine, the radioactive iodine absorbed by the thyroid can injure the gland. Because of the carcinogenic effects of its radiation, there is a significant public health risk in the event of exposure to radioactive iodine. On other hand, due to stable (non-radioactive iodine acts to block radioactive iodine from being taken into the thyroid gland, it can help protect this gland from injury and following side effects. In this query, potassium iodide (also called KI is a salt of stable iodine in a medicine form which is recommended to use sine many years ago. With effective planning and the use of stable iodine prophylaxis, accompanied with other protective implementations, this risk is mostly avoidable. This book contains information such as iodine and physiology kinetic , exposure risk to radioactive iodine, how to use stable iodine in this events , complications attributed to stable(non-radioactive iodine and also at last chapter the final recommendation published by WHO is included.

  4. Thyroid cancer in South Africa - an indicator of regional iodine ...

    African Journals Online (AJOL)

    Objective. Because follicular thyroid cancers predominate in iodine-deficient and papillary cancers predominate in iodine replete populations. we have analysed national and regional (former Transvaal) incidences of these cancer types as a surrogate measure of the population iodine nutritional status in South Africa.

  5. Enhanced excretion of radioactive iodine from the thyroid

    International Nuclear Information System (INIS)

    Bondarchuk, A.K.

    1990-01-01

    It is pointed out that administration of stable iodine (Lugol solution) accelerates excretion of radioactive iodine from the thyroid. Owing to the fact, all the patients subjected to thyroid scanning with 131 I or those who suffered as a result of NPP accident like the Chernobyl one, should take iodine preparations in conventional treatment-and-prophylactic doses for 3-4 weeks

  6. Thyroid disorders in mild iodine deficiency

    DEFF Research Database (Denmark)

    Laurberg, P; Nøhr, S B; Pedersen, K M

    2000-01-01

    in elderly subjects, especially women, with risk of cardiac arrhythmias, osteoporosis, and muscle wasting. The hyperthyroidism is caused by autonomous nodular growth and function of the thyroid gland and it is accompanied by a high frequency of goiter. Pregnant women and small children are not immediately...... endangered but the consequences of severe iodine deficiency for brain development are grave and a considerable safety margin is advisable. Moreover, a shift toward less malignant types of thyroid cancer and a lower radiation dose to the thyroid in case of nuclear fallout support that mild-to-moderate iodine...

  7. Methods to determine iodine plate-out

    International Nuclear Information System (INIS)

    Hougaard, H.; Solgaard, P.; Zak, W.

    1986-03-01

    A literature study on iodines behaviour after release from irradiated fuel rods and a detailed dscription of the ventilation system in the hot cell facility form the basis of chosen conditions for some preliminary experiments using non-radioactive iodine. The conclusion states that the system is well suited for the purpose as is the method of sampling from the surface of the ventilation duct, while the releasing technique and the chemical analysis has to be further developed, neutron activation analysis being most promising. (author)

  8. [Overall child development: beyond pharmacological iodine supplementation].

    Science.gov (United States)

    Gavilán, Enrique; Jiménez de Gracia, Laura

    2013-12-01

    Iodine deficiency is a factor that may compromise child development, but is not the only one. Other health determinants, some of them outside the healthcare system, are able to influence development. Fighting iodine deficiency may be a pragmatic and useful strategy if it is found to be not maleficent, beneficial to health, and cost-effective, and does not make us lose the notion that child development goes beyond psychomotor or cognitive performance. This article analyzes such constraints from a critical point of view. Copyright © 2013 SEEN. Published by Elsevier Espana. All rights reserved.

  9. Considerations regarding iodine prophylaxis in radiological accidents

    International Nuclear Information System (INIS)

    Perez, M.R.; Gisone, P.; Rojo, A.M.; Dubner, D.; Bruno, H.

    1995-01-01

    The indication for the blockade of thyroid gland by the administration of stable iodide is the main countermeasure for diminishing the thyroid uptake of radioiodine following radiological accidents with potential release of radioiodine into the environment in order to avoid deterministic effects and to decrease the probability of stochastic effects. Iodine prophylaxis should be considered along with other countermeasures like sheltering indoors, evacuation and control on contaminated foods. In this communication different factors related to accidental situations regarding iodine prophylaxis are evaluated. A therapeutical scheme is proposed in order to be applied in countries of this region. (author). 4 refs

  10. Coulomb dissociation of N-20,N-21

    NARCIS (Netherlands)

    Roeder, Marko; Adachi, Tatsuya; Aksyutina, Yulia; Alcantara, Juan; Altstadt, Sebastian; Alvarez-Pol, Hector; Ashwood, Nicholas; Atar, Leyla; Aumann, Thomas; Avdeichikov, Vladimir; Barr, M.; Beceiro, Saul; Bemmerer, Daniel; Benlliure, Jose; Bertulani, Carlos; Boretzky, Konstanze; Borge, Maria J. G.; Burgunder, G.; Caamano, Manuel; Caesar, Christoph; Casarejos, Enrique; Catford, Wilton; Cederkall, Joakim; Chakraborty, S.; Chartier, Marielle; Chulkov, Leonid; Cortina-Gil, Dolores; Crespo, Raquel; Pramanik, Ushasi Datta; Diaz-Fernandez, Paloma; Dillmann, Iris; Elekes, Zoltan; Enders, Joachim; Ershova, Olga; Estrade, A.; Farinon, F.; Fraile, Luis M.; Freer, Martin; Freudenberger, M.; Fynbo, Hans; Galaviz, Daniel; Geissel, Hans; Gernhaeuser, Roman; Goebel, Kathrin; Golubev, Pavel; Diaz, D. Gonzalez; Hagdahl, Julius; Heftrich, Tanja; Heil, Michael; Heine, Marcel; Heinz, Andreas; Henriques, Ana; Holl, Matthias; Ickert, G.; Ignatov, Alexander; Jakobsson, Bo; Johansson, Hakan; Jonson, Bjorn; Kalantar-Nayestanaki, Nasser; Kanungo, Rituparna; Kelic-Heil, Aleksandra; Knoebel, Ronja; Kroell, Thorsten; Kruecken, Reiner; Kurcewicz, J.; Kurz, Nikolaus; Labiche, Marc; Langer, Christoph; Le Bleis, Tudi; Lemmon, Roy; Lepyoshkina, Olga; Lindberg, Simon; Machado, Jorge; Marganiec, Justyna; Mostazo Caro, Magdalena; Movsesyan, Alina; Najafi, Mohammad Ali; Nilsson, Thomas; Nociforo, Chiara; Panin, Valerii; Paschalis, Stefanos; Perea, Angel; Petri, Marina; Pietri, S.; Plag, Ralf; Prochazka, A.; Rahaman, Md. Anisur; Rastrepina, Ganna; Reifarth, Rene; Ribeiro, Guillermo; Ricciardi, M. Valentina; Rigollet, Catherine; Riisager, Karsten; Rossi, Dominic; del Rio Saez, Jose Sanchez; Savran, Deniz; Scheit, Heiko; Simon, Haik; Sorlin, Olivier; Stoica, V.; Streicher, Branislav; Taylor, Jon; Tengblad, Olof; Terashima, Satoru; Thies, Ronja; Togano, Yasuhiro; Uberseder, Ethan; Van de Walle, J.; Velho, Paulo; Volkov, Vasily; Wagner, Andreas; Wamers, Felix; Weick, Helmut; Weigand, Mario; Wheldon, Carl; Wilson, G.; Wimmer, Christine; Winfield, J. S.; Woods, Philip; Yakorev, Dmitry; Zhukov, Mikhail; Zilges, Andreas; Zuber, Kai

    2016-01-01

    Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N-20,N-21 are reported. Relativistic N-20,N-21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a

  11. Dissociative depression among women in the community.

    Science.gov (United States)

    Sar, Vedat; Akyüz, Gamze; Oztürk, Erdinç; Alioğlu, Firdevs

    2013-01-01

    This study screened the prevalence and correlates of dissociative disorders among depressive women in the general population. The Dissociative Disorders Interview Schedule and the posttraumatic stress disorder (PTSD) and borderline personality disorder sections of the Structured Clinical Interview for DSM-IV were administered to 628 women in 500 homes. The prevalence of current major depressive episode was 10.0%. Of the women, 26 (40.6%) had the lifetime diagnosis of a DSM-IV, dissociative disorder, yielding a prevalence of 4.1% for dissociative depression. This group was younger (mean age = 30.7 years) than the nondissociative depression women (mean age = 39.6 years). There was no difference between the 2 groups on comorbid somatization disorder, PTSD, or borderline personality disorder. Besides suicide attempts, the dissociative group was characterized by secondary features of dissociative identity disorder; Schneiderian symptoms; borderline personality disorder criteria; and extrasensory perceptions, including possession experiences. They reported suicidality, thoughts of guilt and worthlessness, diminished concentration and indecisiveness, and appetite and weight changes more frequently than the nondissociative group. Early cessation of school education and childhood sexual abuse were frequently reported by the dissociative depression group. With its distinct features, the concept of dissociative depression may facilitate understanding of treatment resistance in, development of better psychotherapy strategies for, and new thinking on the neurobiology and pharmacotherapy of depressive disorders.

  12. Dissociation and the Development of Psychopathology.

    Science.gov (United States)

    Putnam, Frank W.; Trickett, Penelope K.

    This paper reviews the research on dissociation and the development of psychopathology in children and adolescents. Definitions and dimensions of dissociation are addressed, noting its range from normative daydreaming to the extremes found in individuals with multiple personality disorder. Memory dysfunctions, disturbances of identity, passive…

  13. Molecular dissociation in dilute gas

    Science.gov (United States)

    Renfrow, S. N.; Duggan, J. L.; McDaniel, F. D.

    1999-06-01

    The charge state distributions (CSD) produced during molecular dissociation are important to both Trace Element Accelerator Mass Spectrometry (TEAMS) and the ion implantation industry. The CSD of 1.3-1.7 MeV SiN+, SiMg+, SiMn+, and SiZn+ molecules have been measured for elements that do not form atomic negative ions (N, Mg, Mn, and Zn) using a NEC Tandem Pelletron accelerator. The molecules were produced in a Cs sputter negative ion source, accelerated, magnetically analyzed, and then passed through an N2 gas cell. The neutral and charged breakups where analyzed using an electrostatic deflector and measured with particle detectors. Equilibrium CSD were determined and comparisons made between molecular and atomic ion data.

  14. A novel concept to derive iodine status of human populations from frequency distribution properties of a hair iodine concentration.

    Science.gov (United States)

    Prejac, J; Višnjević, V; Drmić, S; Skalny, A A; Mimica, N; Momčilović, B

    2014-04-01

    Today, human iodine deficiency is next to iron the most common nutritional deficiency in developed European and underdeveloped third world countries, respectively. A current biological indicator of iodine status is urinary iodine that reflects the very recent iodine exposure, whereas some long term indicator of iodine status remains to be identified. We analyzed hair iodine in a prospective, observational, cross-sectional, and exploratory study involving 870 apparently healthy Croatians (270 men and 600 women). Hair iodine was analyzed with the inductively coupled plasma mass spectrometry (ICP MS). Population (n870) hair iodine (IH) respective median was 0.499μgg(-1) (0.482 and 0.508μgg(-1)) for men and women, respectively, suggesting no sex related difference. We studied the hair iodine uptake by the logistic sigmoid saturation curve of the median derivatives to assess iodine deficiency, adequacy and excess. We estimated the overt iodine deficiency to occur when hair iodine concentration is below 0.15μgg(-1). Then there was a saturation range interval of about 0.15-2.0μgg(-1) (r(2)=0.994). Eventually, the sigmoid curve became saturated at about 2.0μgg(-1) and upward, suggesting excessive iodine exposure. Hair appears to be a valuable and robust long term biological indicator tissue for assessing the iodine body status. We propose adequate iodine status to correspond with the hair iodine (IH) uptake saturation of 0.565-0.739μgg(-1) (55-65%). Copyright © 2014 Elsevier GmbH. All rights reserved.

  15. Reaction of gaseous mercury with molecular iodine, atomic iodine, and iodine oxide radicals - Kinetics, product studies, and atmospheric implications

    Science.gov (United States)

    Raofie, F.; Snider, G.; Ariya, P.

    2008-12-01

    Mercury is present in the Earth's atmosphere mainly in elemental form. The chemical transformation of mercury in the atmosphere may influence its bioaccumulation in the human food chain as well as its global cycling. We carried out the first kinetic and product studies of the reactions of gaseous mercury with molecular iodine, atomic iodine, and iodine oxide radicals at tropospheric pressure (similar to 740 Torr) and 296 ± 2 K in air and in N2 (1 Torr = 133.3 Pa). Atomic iodine was formed using UV photolysis of CH2I2. IO radicals were formed by the UV photolysis of CH2I2 in the presence of ozone The reaction kinetics were studied using absolute rate techniques with gas chromatographic and mass spectroscopic detection (GC-MS). The measured rate coefficient for the reaction of Hg{0} with I2 was vapor atomic fluorescence spectrometer (CVAFS), and a high-resolution transmission electron microscope (HRTEM) coupled to an energy dispersive spectrometer (EDS). The major reaction products identified were HgI2, HgO, and HgIO or HgOI. The implications of the results are discussed with regards to both the chemistry of atmospheric mercury and its potential implications in the biogeochemical cycling of mercury.

  16. Iodine-129 in the environment

    International Nuclear Information System (INIS)

    Tikhomirov, F.A.; Moiseev, I.T.

    1987-01-01

    The quantitative ratio of aerial and soil entries of 129 I into plants, parameters of its migration in the system of atmosphere-soil-plants-river water, dynamics of transformation and biological availability of 129 I in soil for plants were studied on the basis of field observations and experiments using the radioactive tracers. The doses of human thyroid gland irradiation by 129 I under atmospheric and soil pathways of its transport into diet are estimated. 129 I content in soil due to its systematic, for 50 years, releases into atmosphere is shown to be negligible, agricultural production contamination by 129 I resulting mainly from its fallout onto overground phytomass. The period, needed to achieve 129 I concentration equilibrium in the atmosphere-soil system under constant average 129 I content in the air, varies depending on the soil type from several hundred years (for podzolic soils) up to several thousand years (for chernozem). The 129 I half-accumulation period is equal to 150 years for soddy-podzolic soil and to 700 years for chernozem. In case of 129 I fallout lasting for 100 years the annual increase of its content in overground phytomass due to the transport from soil will account for 0,3% of its atmospheric entry way for soddy-podzolic soil and for 0,1% for chernozem, respectively. For a number of sierozem, yellow soil and calcareous chernozem types this addition is higher (up to 1%). Under constant iodine-129 concentration in air (1 Bq/m3) the absorbed dose for one-year child's thyroid gland in continental area is approximately equal to 2 (Gy/y)/(Bq/m3). The absorbed dose from globally dissipated 129 I under 99% efficiency of gas purification will not exceed 2·10 -7 Gy/y. The input of globally dissipated 129 I, originating from deep underground disposal of nuclear wastes can account for not more than 10 -9 Gy/y. In total, 129 I releases for the coming century is not going to produce limitations for nuclear energetics development. (author)

  17. Dissociation and Memory Fragmentation in Posttraumatic Stress Disorder: An Evaluation of the Dissociative Encoding Hypothesis

    Science.gov (United States)

    Bedard-Gilligan, Michele; Zoellner, Lori A.

    2012-01-01

    Several prominent theories of posttraumatic stress disorder (PTSD) posit that peritraumatic dissociation results in insufficient encoding of the trauma memory and that persistent dissociation prevents memory elaboration, resulting in memory fragmentation and PTSD. In this review, we summarize the empirical literature on peritraumatic and trait dissociation and trauma narrative fragmentation as measured by meta-memory and rater/objective coding. Across 16 studies to date, the association between dissociation and fragmentation was most prominent when examining peritraumatic dissociation and patient's own ratings of memory fragmentation. This relationship did not hold when examining trait dissociation or rater-coded or computer-generated measures of fragmentation. Thus, initial evidence points more toward a strong self-reported association between constructs that is not supported on more objective fragmentation coding. Measurement overlap, construct ambiguity, and exclusion of potential confounds may underlie lack of a strong association between dissociation and objective-rated fragmentation. PMID:22348400

  18. The Shutdown Dissociation Scale (Shut-D)

    Science.gov (United States)

    Schalinski, Inga; Schauer, Maggie; Elbert, Thomas

    2015-01-01

    The evolutionary model of the defense cascade by Schauer and Elbert (2010) provides a theoretical frame for a short interview to assess problems underlying and leading to the dissociative subtype of posttraumatic stress disorder. Based on known characteristics of the defense stages “fright,” “flag,” and “faint,” we designed a structured interview to assess the vulnerability for the respective types of dissociation. Most of the scales that assess dissociative phenomena are designed as self-report questionnaires. Their items are usually selected based on more heuristic considerations rather than a theoretical model and thus include anything from minor dissociative experiences to major pathological dissociation. The shutdown dissociation scale (Shut-D) was applied in several studies in patients with a history of multiple traumatic events and different disorders that have been shown previously to be prone to symptoms of dissociation. The goal of the present investigation was to obtain psychometric characteristics of the Shut-D (including factor structure, internal consistency, retest reliability, predictive, convergent and criterion-related concurrent validity). A total population of 225 patients and 68 healthy controls were accessed. Shut-D appears to have sufficient internal reliability, excellent retest reliability, high convergent validity, and satisfactory predictive validity, while the summed score of the scale reliably separates patients with exposure to trauma (in different diagnostic groups) from healthy controls. The Shut-D is a brief structured interview for assessing the vulnerability to dissociate as a consequence of exposure to traumatic stressors. The scale demonstrates high-quality psychometric properties and may be useful for researchers and clinicians in assessing shutdown dissociation as well as in predicting the risk of dissociative responding. PMID:25976478

  19. The Shutdown Dissociation Scale (Shut-D

    Directory of Open Access Journals (Sweden)

    Inga Schalinski

    2015-05-01

    Full Text Available The evolutionary model of the defense cascade by Schauer and Elbert (2010 provides a theoretical frame for a short interview to assess problems underlying and leading to the dissociative subtype of posttraumatic stress disorder. Based on known characteristics of the defense stages “fright,” “flag,” and “faint,” we designed a structured interview to assess the vulnerability for the respective types of dissociation. Most of the scales that assess dissociative phenomena are designed as self-report questionnaires. Their items are usually selected based on more heuristic considerations rather than a theoretical model and thus include anything from minor dissociative experiences to major pathological dissociation. The shutdown dissociation scale (Shut-D was applied in several studies in patients with a history of multiple traumatic events and different disorders that have been shown previously to be prone to symptoms of dissociation. The goal of the present investigation was to obtain psychometric characteristics of the Shut-D (including factor structure, internal consistency, retest reliability, predictive, convergent and criterion-related concurrent validity.A total population of 225 patients and 68 healthy controls were accessed. Shut-D appears to have sufficient internal reliability, excellent retest reliability, high convergent validity, and satisfactory predictive validity, while the summed score of the scale reliably separates patients with exposure to trauma (in different diagnostic groups from healthy controls.The Shut-D is a brief structured interview for assessing the vulnerability to dissociate as a consequence of exposure to traumatic stressors. The scale demonstrates high-quality psychometric properties and may be useful for researchers and clinicians in assessing shutdown dissociation as well as in predicting the risk of dissociative responding.

  20. Low iodine content in the diets of hospitalized preterm infants.

    Science.gov (United States)

    Belfort, Mandy B; Pearce, Elizabeth N; Braverman, Lewis E; He, Xuemei; Brown, Rosalind S

    2012-04-01

    Iodine is critical for normal thyroid hormone synthesis and brain development during infancy, and preterm infants are particularly vulnerable to the effects of both iodine deficiency and excess. Use of iodine-containing skin antiseptics in intensive care nurseries has declined substantially in recent years, but whether the current dietary iodine intake meets the requirement for hospitalized preterm infants is unknown. The aim of the study was to measure the iodine content of enteral and parenteral nutrition products commonly used for hospitalized preterm infants and estimate the daily iodine intake for a hypothetical 1-kg infant. We used mass spectrometry to measure the iodine concentration of seven preterm infant formulas, 10 samples of pooled donor human milk, two human milk fortifiers (HMF) and other enteral supplements, and a parenteral amino acid solution and soy-based lipid emulsion. We calculated the iodine provided by typical diets based on 150 ml/kg · d of formula, donor human milk with or without HMF, and parenteral nutrition. Preterm formula provided 16.4-28.5 μg/d of iodine, whereas unfortified donor human milk provided only 5.0-17.6 μg/d. Adding two servings (six packets) of Similac HMF to human milk increased iodine intake by 11.7 μg/d, whereas adding two servings of Enfamil HMF increased iodine intake by only 0.9 μg/d. The other enteral supplements contained almost no iodine, nor did a parenteral nutrition-based diet. Typical enteral diets for hospitalized preterm infants, particularly those based on donor human milk, provide less than the recommended 30 μg/d of iodine, and parenteral nutrition provides almost no iodine. Additional iodine fortification should be considered.

  1. Water dissociation and CO oxidation over Au/anatase catalyst. A DFT-D2 study

    Science.gov (United States)

    Saqlain, Muhammad Adnan; Hussain, Akhtar; Siddiq, Muhammad; Leitão, Alexandre A.

    2018-03-01

    With the help of DFT-D2 methodology, we have investigated the adsorption of water on clean anatase(001) and Au/anatase(001). In the former case, adsorption energies of H2O differ to small extent computed employing GGA = PW91 and DFT-D2 methods. While the GGA = PW91 predicts that water would desorb close to 650 K on the TiO2 surface, the DFT-D2 predicts that desorption is most likely to occur above 700 K. A comparison of water adsorption on TiO2 and Au/TiO2 surfaces shows that the TiO2 prefers dimer adsorption whereas the Au/TiO2 prefers monomer adsorption. We found that the diffusion of surface hydroxyls on to the Au cluster from the Au/TiO2 periphery is unlikely and it seems that the CO oxidation would occur at the Au/TiO2 boundary. The results show that water dissociation and CO oxidation steps occur easily on Au/TiO2 indicating that this could be good alternative catalyst for water gas shift reaction industry.

  2. Retrospective reconstruction of Iodine-131 distribution through the analysis of Iodine-129

    Science.gov (United States)

    Matsuzaki, Hiroyuki; Muramatsu, Yasuyuki; Ohno, Takeshi; Mao, Wei

    2017-09-01

    Iodine-131 distribution released from the Fukushima Dai-ichi Nuclear Power Plant accident was reconstructed through the iodine-129 measurements. From nearly 1,000 surface soil samples iodine was extracted by the pyro hydrolysis method. Extracted iodine was then mixed with carrier, purified and finally collected as silver iodide. Silver iodide sample was pressed into the cathode holder and set at the ion source of the MALT facility, The University of Tokyo. The isotopic ratio 129I/127I was measured by means of Accelerator Mass Spectrometry. From 129I data obtained, 131I deposition map was constructed. There observed various fine structures in the map which could not estimated neither by the simulation nor 137Cs distribution.

  3. Retrospective reconstruction of Iodine-131 distribution through the analysis of Iodine-129

    Directory of Open Access Journals (Sweden)

    Matsuzaki Hiroyuki

    2017-01-01

    Full Text Available Iodine-131 distribution released from the Fukushima Dai-ichi Nuclear Power Plant accident was reconstructed through the iodine-129 measurements. From nearly 1,000 surface soil samples iodine was extracted by the pyro hydrolysis method. Extracted iodine was then mixed with carrier, purified and finally collected as silver iodide. Silver iodide sample was pressed into the cathode holder and set at the ion source of the MALT facility, The University of Tokyo. The isotopic ratio 129I/127I was measured by means of Accelerator Mass Spectrometry. From 129I data obtained, 131I deposition map was constructed. There observed various fine structures in the map which could not estimated neither by the simulation nor 137Cs distribution.

  4. Stable iodine prophylaxis. Recommendations of the 2nd UK Working Group on Stable Iodine Prophylaxis

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The Working Group reviewed the revised Who guidance and the information published since 1991 on the risks of thyroid cancer in children from radioiodine and the risks of side effects from stable iodine. In particular, it reviewed data compiled on the incidence of thyroid cancers in children following the accident at the Chernobyl nuclear power plant in 1986. It considered whether the NRPB Earls were still appropriate, in the light of the new data. It also reviewed a range of other recommendations given by the 1st Working Group, concerning the chemical form of stable iodine tablets and practical issues concerning implementation of stable iodine prophylaxis. Finally, it reviewed the Patient Information Leaflet that is required, by law, to be included in each box of tablets and provided suggestions for information to be included in a separate information leaflet to be handed out to the public when stable iodine tablets are distributed.

  5. Weight, iodine content and iodine uptake of the thyroid gland of normal Japanese

    International Nuclear Information System (INIS)

    Yoshizawa, Yasuo; Kusama, Tomoko

    1976-01-01

    Various questions arise in the application of ICRP ''Standard Man'' values to Japanese. One of the questions is that ''Standard Man'' values of the thyroid are different from normal Japanese values. A systematic survey of past reports was carried out with a view to search for normal Japanese values of the thyroid. The subjects of search were weight, iodine content and iodine uptake rate (f sub(w)) of the thyroid. These are important factors in the estimation of the radiation dose of the thyroid caused by internal contamination of radioiodine, and are foreseen to have the difference between Japanese and ''Standard Man''. The result of study suggested that the weight of the thyroid of normal Japanese is about 19 g for adult male and about 17 g for adult female, and that the iodine content is 12-22 mg and iodine uptake rate (f sub(w)) is about 0.2. (auth.)

  6. Iodine flow rate measurement for COIL with the chemical iodine generator based on absorption spectroscopy

    Science.gov (United States)

    Zhao, Weili; Zhang, Yuelong; Zhang, Peng; Xu, Mingxiu; Jin, Yuqi; Sang, Fengting

    2015-02-01

    A dual-components absorption method based on absorption spectroscopy was described in the paper. It can easily eliminate the influence of the serious contamination and aerosol scattering on IFR measurement by utilizing the absorptions of iodine vapor and chlorine on two different wavelengths respectively. According to the character that there is no other gaseous product in the reaction besides iodine vapor, IFR in real time can be obtained by the connections of the pressure and the flow rate among chlorine remainder, iodine vapor, and the buffer gas. We used this method to measure IFR for the first time at the exit of a chemical iodine generator. The average of IFR is coincident with that calculated by chemical weighting mass.

  7. A possible highly active supported Ni dimer catalyst for O{sub 2} dissociation: A first-principles study

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Shan [College of Physics and Materials Science, Henan Normal University, Xinxiang, Henan 453007 (China); Zhang, Yanxing, E-mail: 2016025@htu.edu.cn [College of Physics and Materials Science, Henan Normal University, Xinxiang, Henan 453007 (China); Zhang, Xilin; Mao, Jianjun [College of Physics and Materials Science, Henan Normal University, Xinxiang, Henan 453007 (China); Yang, Zongxian, E-mail: yzx@henannu.edu.cn [College of Physics and Materials Science, Henan Normal University, Xinxiang, Henan 453007 (China); Collaborative Innovation Center of Nano Functional Materials and Applications, Henan Province (China)

    2017-04-30

    Graphical abstract: The minimum energy paths (MEPs) for the dissociation process of O{sub 2} on the surfaces of bare YSZ (111) and Ni{sub n}/YSZ (111) (n = 1, 2 and 3). - Highlights: • The catalytic activity of supported metal catalysts is closely related to the size of metal particles. • The dissociation of O{sub 2} on the YSZ (111) surface is largely enhanced by the supported Ni cluster. • The supported Ni dimer is predicted to be the smallest Ni cluster needed for efficient O{sub 2} dissociation. • The results would provide an important reference to improve the activity and efficiency of the Ni/YSZ(111) nanocomposite catalysts in cost-effective materials. - Abstract: The adsorption and dissociation of O{sub 2} on the supported small nickel clusters with one-, two-, three-Ni atoms on yttria-stabilized zirconia (YSZ) (111) surfaces, as well as those on the bare YSZ(111) and Ni(111) surfaces are comparatively studied using ab initio density functional theory calculations. It is found that the dissociation of O{sub 2} on the YSZ(111) surface is largely enhanced by the supported Ni dimer, which is predicted to be the smallest Ni cluster needed for efficient O{sub 2} dissociation. The results would provide an important reference to improve the activity and efficiency of the Ni/YSZ(111) nanocomposite catalysts in cost-effective materials.

  8. Psychotherapy and Pharmacotherapy for Patients with Dissociative Identity Disorder

    OpenAIRE

    Gentile, Julie P.; Dillon, Kristy S.; Gillig, Paulette Marie

    2013-01-01

    There is a wide variety of what have been called “dissociative disorders,” including dissociative amnesia, dissociative fugue, depersonalization disorder, dissociative identity disorder, and forms of dissociative disorder not otherwise specified. Some of these diagnoses, particularly dissociative identity disorder, are controversial and have been questioned by many clinicians over the years. The disorders may be under-diagnosed or misdiagnosed, but many persons who have experienced trauma rep...

  9. Source And Sink Of Iodine For Drinking Water

    Science.gov (United States)

    Sauer, Richard L.; Flanagan, David T.; Gibbons, Randall E.

    1991-01-01

    Proposed system for controlling concentration of iodine in potable water exploits temperature dependence of equilibrium partition of iodine between solution in water and residence in ion-exchange resin. Used to maintain concentration of iodine sufficient to kill harmful microbes, but not so great to make water unpalatable. Requires little attention, yet controls concentration of iodine more precisely than iodination and deiodination by manual techniques. Conceived for use aboard spacecraft, system has terrestrial applications in regions where water must be kept potable, resupply difficult, and system must operate largely unattended.

  10. Iodine and microbial interactions in an organic soil

    International Nuclear Information System (INIS)

    Sheppard, M.I.; Hawkins, J.L.

    1995-01-01

    Iodine-129 in groundwater discharging from a geological disposal vault could accumulate in wetlands by chemical sorption onto low pH, highly organic solid surfaces or by direct or indirect microbial processes. Previous work indicated that saturation of anion sorption sites, microbial toxicity, or swamping of the I reduction/oxidation reaction decreased the retention of a wetland sphagnum for iodine with increased iodine porewater concentrations. Bog water and peat of an iodine-rich bog were studied to elucidate the role of micro-organisms in the retention and accumulation of iodine in a temperate wetland. (author)

  11. Generation of atomic iodine via fluorine for chemical oxygen-iodine laser

    Czech Academy of Sciences Publication Activity Database

    Jirásek, Vít; Špalek, Otomar; Čenský, Miroslav; Picková, Irena; Kodymová, Jarmila; Jakubec, Ivo

    2007-01-01

    Roč. 334, - (2007), s. 167-174 ISSN 0301-0104 R&D Projects: GA ČR GA202/05/0359 Grant - others:USAF European Office for Research and Development(XE) FA 8655-05-M-4027 Institutional research plan: CEZ:AV0Z10100523; CEZ:AV0Z40320502 Keywords : atomic iodine * atomic fluorine * chemical oxygen-iodine laser Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.805, year: 2007

  12. Chemical oxygen-iodine laser with atomic iodine generated via fluorine atoms

    Czech Academy of Sciences Publication Activity Database

    Jirásek, Vít; Čenský, Miroslav; Špalek, Otomar; Kodymová, Jarmila; Picková, Irena; Jakubec, Ivo

    2008-01-01

    Roč. 345, č. 1 (2008), 14-22 ISSN 0301-0104 R&D Projects: GA ČR GA202/05/0359 Institutional research plan: CEZ:AV0Z10100523; CEZ:AV0Z40320502 Keywords : atomic iodine * atomic fluorine * chemical oxygen–iodine laser * COIL Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.961, year: 2008

  13. Dissociative Part-Dependent Resting-State Activity in Dissociative Identity Disorder : A Controlled fMRI Perfusion Study

    NARCIS (Netherlands)

    Schlumpf, Yolanda R.; Reinders, Antje A. T. S.; Nijenhuis, Ellert R. S.; Luechinger, Roger; van Osch, Matthias J. P.; Jaencke, Lutz

    2014-01-01

    Background: In accordance with the Theory of Structural Dissociation of the Personality (TSDP), studies of dissociative identity disorder (DID) have documented that two prototypical dissociative subsystems of the personality, the "Emotional Part'' (EP) and the "Apparently Normal Part'' (ANP), have

  14. Radio-active iodine uptake in vitiligo

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, V.; Shankar, V.; Chaudhary, S.; Bhatia, K.K.; Mehta, L.K.; Arora, D.R. (Medical College and Hospital, Rohtak-124001 (India))

    1990-01-01

    Vitiligo and thyroid disease are commonly associated disorders. Twenty-two clinically euthyroid vitiligo patients were studied for functional assessment of thyroid by radioactive iodine uptake assay. Half of them showed abnormal uptake values at 24 hours. Of these patients, 90% had lower values indicating a tendency towards developing hypothyroid state. Subclinical thyroid dysfunction in vitiligo appears to be an adaptive change. (author).

  15. High power atomic iodine photodissociation lasers

    International Nuclear Information System (INIS)

    Palmer, R.E.; Padrick, T.D.; Jones, E.D.

    1976-01-01

    The atomic iodine photodissociation laser has developed into a system capable of producing nanosecond or shorter pulses of near infrared radiation with energies well in excess of a hundred J. Discussed are the operating characteristics, advantages, and potential problem areas associated with this laser

  16. prevalence and severity of iodine deficiency

    African Journals Online (AJOL)

    GB

    2012-11-03

    Nov 3, 2012 ... Iodine deficiency causes reduced production of thyroid hormones (T3/T4). A decrease in the serum level of T3/T4 triggers the secretion of high amount of pituitary thyroid stimulating hormone, which stimulates thyroid glandular activities that results in enlargement of the gland (9). Thyroid hormones play an ...

  17. Volatile suppressing method for radioactive iodine

    International Nuclear Information System (INIS)

    Ohara, Atsushi; Haruguchi, Keiko.

    1997-01-01

    In the present invention, a metal plate is disposed above the pool water surface of a suppression chamber disposed to a reactor container in order to reduce evaporation of radioactive iodine released from a suppression pool. A metal plate is disposed above the pool water surface of the suppression chamber disposed to the reactor container. In addition, a metal plate is disposed around the space connecting a bent tube extending from a dry well to underwater of suppression pool water and a gas bent tube extending from the suppression chamber to an emergency gas processing system. Spray water is supplied for cooling the suppression chamber d as a means for cooling the metal plate. Then, among iodine released to the suppression chamber, elemental iodine liberated from the pool water is deposited on the surface of the metal plate, and the amount of iodine to be flown into and processed by an emergency gas processing system or a filter bent system can be reduced. (T.M.)

  18. Iodine-125 seeds for cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Rostelato, Maria E.C.M.; Zeituni, Carlos A.; Feher, Anselmo; Moura, Joao A.; Moura, Eduardo S.; Nagatomi, Helio R.; Manzoli, Jose E.; Souza, Carla D., E-mail: elisaros@ipen.b, E-mail: czeituni@pobox.co, E-mail: afeher@ipen.b, E-mail: jmoura31@yahoo.com.b, E-mail: esmoura@ipen.b, E-mail: hrnagato@ipen.b, E-mail: jemanzoli@ipen.b, E-mail: cdsouza@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Karam, Dib, E-mail: dib.karan@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Escola de Artes, Ciencias e Humanidades

    2009-07-01

    In Brazil, cancer has become one of the major public health problems. An estimate by the Health Ministry showed that 466,430 people had the disease in the country in 2008. The prostate cancer is the second largest death cause among men. The National Institute of Cancer estimated the occurrence of 50,000 new cases for 2009. Some of these patients are treated with Brachytherapy, using Iodine-125 seeds. By this technique, small seeds with Iodine-125, a radioactive material, are implanted in the prostate. The advantages of radioactive seed implants are the preservation of healthy tissues and organs near the prostate, besides the low rate of impotence and urinary incontinence. The Energy and Nuclear Research Institute - IPEN, which belongs to the Nuclear Energy National Commission - CNEN, established a program for the development of the technique and production of Iodine-125 seeds in Brazil. The estimate for the 125-Iodine seeds demand is of 8,000 seeds/month and the laboratory to be implanted will need this production capacity. The purpose of this paper is to explain the project status and show some data about the seeds used in the country. The project will be divided in two phases: technological development of a prototype and a laboratory implementation for the seeds production. (author)

  19. The Iodine Content in Urine, Faeces and Selected Organs of Rats Fed Lettuce Biofortified with Iodine Through Foliar Application.

    Science.gov (United States)

    Rakoczy, Roksana; Kopeć, Aneta; Piątkowska, Ewa; Smoleń, Sylwester; Skoczylas, Łukasz; Leszczyńska, Teresa; Sady, Włodzimierz

    2016-12-01

    Iodine is an essential trace element for humans. Foliar application of micronutrients is successfully used in order to increase the concentration of essential elements in vegetables. The aim of this study was to evaluate the iodine absorption in the rat organism fed foliar biofortified lettuce. The presented study was consisted of the vegetative and animal experiment. In the vegetative experiment with lettuce, two combinations of foliar application were used: (1) control-without iodine application and (2) iodine application in the potassium iodide (KI) form. In the animal experiment, Wistar rats were divided to four groups, which received one of four diets: (1) C-control diet containing iodine in the KI form, (2) D-diet deficient in iodine, (3) D + BL-diet containing biofortified lettuce, and (4) D + CL-diet containing control lettuce (as the only source of iodine in diet, respectively). The diets contained 0.260, 0.060, 0.254 and 0.075 mg I/kg, respectively. In order to determine the iodine absorption in the rat organisms, the content of this trace element was measured in urine, faeces and in selected organs with the use of the ICP-OES technique. Foliar application of the KI increased the content of iodine in lettuce. The rats from the D + BL group excreted significantly less iodine in their urine and faeces and also accumulated more iodine in the organs than the rats from the C group. Iodine with biofortified lettuce was much bioavailable for rodents than iodine from control diet. Biofortified lettuce can be a source of iodine in a diet of human and can improve iodine nutrition.

  20. 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.

  1. Applicability of Activated Carbon to Treatment of Waste Containing Iodine-Labeled Compounds

    International Nuclear Information System (INIS)

    Gad, H.M.H.; El-Mouhty, N.R.A.; Aly, H.F.

    2008-01-01

    The applicability of activated carbon prepared from sawdust (SD) by one-step chemical activation process using H 3 PO 4 (H) to treatment of aqueous waste contaminated with iodine-labeled prolactin (I-PRL) has been investigated. Treatment processes were performed under the varying conditions; contact time, temperature, carbon type, carbon dosage, and different particle size of activated carbon (SDH). Effect of aqueous waste volume has been investigated to calculate the batch factor (V/M) and the distribution coefficient (K d ). The used activated carbon (SDH) was characterized by N 2 adsorption, FTIR, density, ph, point of zero charge ph p zc, moisture and ash content. Methylene blue (MB) and iodine number was calculated by adsorption from solution. In order to investigate the mechanism of sorption and potential rate controlling steps, pseudo first- and second-order equations, intra particle diffusion equation and the Elovich equation have been used to test experimental data. Kinetic analysis of the four models has been carried out for system variables in order to assess which model provides the best fit predicted data with experimental results. 7 M NaOH can be used for regeneration of spent SDH activated carbon with the efficiency of 99.6% and the regenerated carbon can be reused for five cycles effectively. The prospect of applying the SDH activated carbon prepared from agricultural by-product, sawdust, to treatment of aqueous waste contaminated with I-PRL appears promising and is considered highly applicable because of its high adsorption capacity, available at low cost, easily regenerated and reused

  2. Dietary iodine and accumulation of radioiodine in thyroids of chickens

    International Nuclear Information System (INIS)

    Newcomer, W.S.

    1978-01-01

    Groups of hatchling white leghorn cockerels were fed a basic, semisynthetic low-iodine diet to which various amounts of iodide were added: 0 up to 100 μg I/g feed. Growth rates were unaffected by the range of dietary iodine content. A transitory goiter occurred only in the group fed the basic low-I diet. Half-life of 131 I in the thyroid increased directly and fractional turnover rate inversely with increase of dietary iodine. Trichloroacetic acid-soluble iodine in serum did not accurately reflect variation of dietary iodine. However, effective clearance and binding rate constants did decrease proportionally to dietary iodine increase beyond the first 3 to 5 days. Concentration of iodine in thyroid was directly proportional to dietary iodine after 10 days. There was no consistent correlation between thyroxine or triiodothyronine and dietary iodine except in general terms of high and low dietary iodine groups. The avian thyroid exhibits great lability in adjusting functionally to a wide range of dietary iodine contents

  3. WHO's new recommendations about iodine prophylaxis at nuclear catastrophes

    International Nuclear Information System (INIS)

    Paile, Wendla

    1999-01-01

    WHO has prepared new advice about using stable iodine as protection against emission of radioactive iodine from nuclear catastrophes. The experiences from Chernobyl show that the risk for thyroid gland cancer after emission of radio-iodine is significant. The risk of serious side effects of stable iodine as single dose is stated to be minimal. Stable iodine is a safe, effective remedy for protecting the thyroid gland against radioactive iodine. It is recommended to adjust different criteria for iodine prophylaxis for new-born, children, young people and adults older than 40 years. For children of the age up to 18 years iodine prophylaxis should be considered at 10 mGy thyroid gland doses, and for young adults at 100 mGy. For adults of 40 years or more the cancer risk of radioactive iodine is very low and iodine prophylaxis is unnecessary provided that the expected does not exceed 5 Gy. The new information about risk and advantage must be considered in planning for distribution and storage of stable iodine. WHO also commends that everybody has the possibility to buy it in a pharmacy. (EHS)

  4. A Review: Radiographic Iodinated Contrast Media-Induced Thyroid Dysfunction

    Science.gov (United States)

    Leung, Angela M.; Braverman, Lewis E.; Brent, Gregory A.; Pearce, Elizabeth N.

    2015-01-01

    Context: Thyroid hormone production is dependent on adequate iodine intake. Excess iodine is generally well-tolerated, but thyroid dysfunction can occur in susceptible individuals after excess iodine exposure. Radiological iodinated contrast media represent an increasingly common source of excess iodine. Objective: This review will discuss the thyroidal response after acute exposure to excess iodine; contrast iodine-induced thyroid dysfunction; risks of iodine-induced thyroid dysfunction in vulnerable populations, such as the fetus, neonate, and patients with impaired renal function; and recommendations for the assessment and treatment of contrast iodine-induced thyroid dysfunction. Methods: Data for this review were identified by searching PubMed, Google Scholar, and references from relevant articles from 1948 to 2014. Conclusions: With the increase in the use of computed tomography scans in the United States, there is increasing risk of contrast-induced thyroid dysfunction. Patients at risk of developing iodine-induced thyroid dysfunction should be closely monitored after receiving iodinated contrast media and should be treated as needed. PMID:25375985

  5. An assessment of iodine in cheese in Macedonia

    International Nuclear Information System (INIS)

    Bogdanov, Bogdan; Gonev, Mihail; Tadzher, Isak S.

    1998-01-01

    We assessed some products in Macedonian food containing iodine: milk, bread, eggs, iodized salt. These nutritional items are deficient in iodine compared to western technology of,food preparation. Cheese prepared as white cheese from sheep and cow's milk is a much-used nutritional product. According to the Central Macedonian Statistical Bureau at the. Ministry of Health the laboratory measured iodine dosage in order to have an estimation of what the contribution of cheese is in the daily Macedonian diet. The collection of cheese was independently performed by the food inspectors in all regions of Macedonia. In June 1998 all specimens were in the laboratory. Macedonian white cheese has 57 micro g/dl iodine. In comparison to other nutritional items as milk, eggs and bread with a low contingent of iodine, the Macedonian cheese covers a good part of daily iodine necessity. We present our results with a brief comment on iodine metabolism. (Original)

  6. Iodine intake as a determinant of thyroid disorders in populations

    DEFF Research Database (Denmark)

    Laurberg, Peter; Cerqueira, Charlotte; Ovesen, Lars

    2010-01-01

    of all comparison, the most serious association between disease and the level of iodine intake in a population. In less severe iodine deficiency, the normal thyroid gland is able to adapt and keep thyroid hormone production within the normal range. However, the prolonged thyroid hyperactivity associated...... and mortality. Conclusion: Even minor differences in iodine intake between populations are associated with differences in the occurrence of thyroid disorders. Both iodine intake levels below and above the recommended interval are associated with an increase in the risk of disease in the population. Optimally......Depending on the availability of iodine, the thyroid gland is able to enhance or limit the use of iodine for thyroid hormone production. When compensation fails, as in severely iodine-deficient populations, hypothyroidism and developmental brain damage will be the dominating disorders. This is, out...

  7. Iodine content in drinking water and other beverages in Denmark

    DEFF Research Database (Denmark)

    Rasmussen, Lone Banke; Larsen, Erik Huusfeldt; Ovesen, L.

    2000-01-01

    Objective: To investigate the variation in iodine content in drinking water in Denmark and to determine the difference in iodine content between organic and non-organic milk. Further, to analyse the iodine content in other beverages. Design and setting: Tap water samples were collected from 41...... evenly distributed localities in Denmark. Organic and non-organic milli was collected at the same time (twice summer and twice winter). Soft drinks, beers and juice were collected from different Danish producers and wine from different countries. All samples were analysed for iodine using inductively...... coupled mass spectrometry. Results: Iodine in tap water varied from 2.1 to 30.2 mu g/l; the iodine content was in general highest in the eastern part of Denmark and lowest in the western part of Denmark. Organic milk was found to have a lower iodine content than non-organic milk. Conclusions: Large...

  8. From state dissociation to status dissociatus.

    Science.gov (United States)

    Antelmi, Elena; Ferri, Raffaele; Iranzo, Alex; Arnulf, Isabelle; Dauvilliers, Yves; Bhatia, Kailash P; Liguori, Rocco; Schenck, Carlos H; Plazzi, Giuseppe

    2016-08-01

    The states of being are conventionally defined by the simultaneous occurrence of behavioral, neurophysiological and autonomic descriptors. State dissociation disorders are due to the intrusion of features typical of a different state into an ongoing state. Disorders related to these conditions are classified according to the ongoing main state and comprise: 1) Dissociation from prevailing wakefulness as seen in hypnagogic or hypnopompic hallucinations, automatic behaviors, sleep drunkenness, cataplexy and sleep paralysis 2) Dissociation from rapid eye movement (REM) sleep as seen in REM sleep behavior disorder and lucid dreaming and 3) Dissociation from NREM sleep as seen in the disorders of arousal. The extreme expression of states dissociation is characterized by the asynchronous occurrence of the various components of the different states that prevents the recognition of any state of being. This condition has been named status dissociatus. According to the underlying disorders/diseases and to their severity, among status dissociatus we may recognize disorders in which such an extreme dissociation occurs only at night time or intermittently (i.e., autoimmune encephalopathies, narcolepsy type 1 and IgLON5 parasomnia), and others in which it occurs nearly continuously with complete loss of any conventionally defined state of being, and of the circadian pattern (agrypnia excitata). Here, we render a comprehensive review of all diseases/disorders associated with state dissociation and status dissociatus and propose a critical classification of this complex scenario. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Iodine, krypton and xenon retention efficiencies of silver impregnated silica gel media with different silver loadings and under different test conditions

    International Nuclear Information System (INIS)

    Motes, B.G.; Fernandez, S.J.; Tkachyk, J.W.

    1983-02-01

    The purpose of an independent study conducted by Exxon Nuclear Idaho, Co. (ENICO) was to evaluate a silver impregnated silica gel adsorption medium associated with a radioiodine air sampler developed at Brookhaven National Laboratory (BNL). Specifically, ENICO's responsibility was to evaluate the iodine and noble gas retention efficiencies of the adsorption medium. The evaluation was comprised of a four-phase program: 1) test assemblies capable of challenging the silver silica gel filled adsorber canister with radioiodine species or noble gases at flow rates up to 10 scfm and relative humidities up to 83% were constructed; 2) more than 45 kgs of the 4 and 8% silver impregnated silica gel were prepared and characterized for particle size distribution, bulk silver content, bulk density, and silver content by particle size; 3) iodine species retention efficiencies of the silver silica gel were determined; and 4 krypton and xenon retention efficiencies were measured. The iodine species retention efficiencies were greater than 90% under most conditions. A combination of flow rates >5 scfm and 4% silver loaded silica gel reduced the methyl iodide retention efficiency to less than 90%. The retention efficiencies for both krypton and xenon were on the order of 8 x 10 -2 % and were not affected greatly by any test variable except test duration. A reduced retention efficiency with increased test durations indicates adsorption equilibrium may be established within five minutes. (author)

  10. Theoretical study of CCl(4) adsorption and hydrogenation on a Pt (111) surface.

    Science.gov (United States)

    Lu, Guiwu; Lan, Jianhui; Li, Chunxi; Wang, Wenchuan; Wang, Chunlei

    2006-12-07

    The adsorption and hydrogenation of carbon tetrachloride (CCl(4)) on a Pt (111) surface have been investigated using density functional theory (DFT). We have performed calculations on the adsorption energies and structures of CCl(4) on four different adsorption sites of a Pt (111) surface using the full adsorbate geometry optimization method. The results show that the adsorption energy of all of the potential sites is less than -17 kcal/mol, which indicates that CCl(4) is physiosorbed on a Pt (111) surface through van der Waals interactions. The dissociation and hydrogenation pathways were investigated by a transition state search. For the Pt(15), Pt(19), and Pt(25) cluster surfaces, the activation energies of dissociation obtained in this work are 15.69, 16.94, and 16.77 kcal/mol, respectively. The hydrogenation of CCl(3). was studied at the on-top site of the Pt(15) cluster, and the calculated activation energy is 5.06 kcal/mol. The small activation energies indicate that the Pt (111) surface has high catalytic activity for the CCl(4) hydrogenation reaction. In addition, the Hirshfeld population analysis reveals that the charge transfer from the Pt (111) surface to the adsorbates occurs in both the dissociation and hydrogenation pathways.

  11. Regenerative adsorption distillation system

    KAUST Repository

    Ng, Kim Choon

    2013-12-26

    There is provided a regenerative adsorption distillation system comprising a train of distillation effects in fluid communication with each other. The train of distillation effects comprises at least one intermediate effect between the first and last distillation effects of the train, each effect comprising a vessel and a condensing tube for flow of a fluid therein. The system further comprises a pair of adsorption-desorption beds in vapour communication with the last effect and at least one intermediate effect, wherein the beds contain an adsorbent that adsorbs vapour from the last effect and transmits desorbed vapour into at least one of the intermediate effect.

  12. Evaluation of soil-plant transfer factors of iodine. Estimation of annual ingestion for iodine from the diet

    International Nuclear Information System (INIS)

    Saas, Arsene.

    1980-11-01

    The author presents the iodine middle contents of the soils and vegetables. A synthesis on the iodine evolution in the soils and vegetables allows to conclude that the vegetable absorption of this isotope is correlated with the isotopiquely exchangeable iodine of the soil. The soil-plant transfer-factors are calculated for the vegetables, cereals, fruits from the stable iodine quantitative analysis. The annual iodine ingestion has been estimated from the dietary of the European Communites areas. This one is a little different of the quantity estimated by CRESTA-LACOURLY-R 2979, yet the contribution by consummation unity is different [fr

  13. Energy distribution in dissociations of polyatomic molecules

    International Nuclear Information System (INIS)

    Koernig, S.A.

    1989-01-01

    In this thesis studies are reported of fragmentation processes in polyatomic molecules. In order to find out which dessocaciation reactions take place, how they are brought about by the internal energy of the reactant, and to investigate the structure of the dissociating 'transition state', the fragment mass and the corresponding kinetic energy release (KER) are determined by differential translational spectroscopy using a position and time sensitive two-particle coincidence detector. The results are interpreted using the statistical theory of unimolecular dissociation. It turns out that the standard assumptions of the theory, especially in calculating KER-distributions, are not realistic in all molecules considered. Dissociation is induced by the neutralization with alkali metal vapour. In ch. 2 the experimental method and the analysis of the data (dissociation pathways, branching ratios and ε-d-distributions) are introduced and exemplified by measurements of cyclohexane, which represents the upper limit in precursor and fragment mass accessible in the apparatus. In ch. 3 a study is reported of the molecules methylchloride (CH 3 Cl) and the acetylradical (CH 3 CO). In spite of their similar geometric structures, completely different dissociation mechanisms have been found. Methylchloride dissociates via a repulsive state; acetyl radicals show energy scrambling. The energy distribution from dissociating acetyl exemplifies dynamical effects in the dissociation. In ch. 4 an investigation of a number of prototype hydrocarbons is presented. The dissociation pathways of several small linear alkanes indicate that neutralization takes place to unknown repulsive potentials, of which the position and steepness are determined from the kinetic energy release. (author). 118 refs.; 40 figs.; 5 tabs

  14. Dissociation in Psychiatric Disorders: A Meta-Analysis of Studies Using the Dissociative Experiences Scale.

    Science.gov (United States)

    Lyssenko, Lisa; Schmahl, Christian; Bockhacker, Laura; Vonderlin, Ruben; Bohus, Martin; Kleindienst, Nikolaus

    2018-01-01

    Dissociation is a complex, ubiquitous construct in psychopathology. Symptoms of dissociation are present in a variety of mental disorders and have been connected to higher burden of illness and poorer treatment response, and not only in disorders with high levels of dissociation. This meta-analysis offers a systematic and evidence-based study of the prevalence and distribution of dissociation, as assessed by the Dissociative Experiences Scale, within different categories of mental disorders, and it updates an earlier meta-analysis. More than 1,900 original publications were screened, and 216 were included in the meta-analysis, comprising 15,219 individuals in 19 diagnostic categories. The largest mean dissociation scores were found in dissociative disorders (mean scores >35), followed by posttraumatic stress disorder, borderline personality disorder, and conversion disorder (mean scores >25). Somatic symptom disorder, substance-related and addictive disorders, feeding and eating disorders, schizophrenia, anxiety disorder, OCD, and most affective disorders also showed mean dissociation scores >15. Bipolar disorders yielded the lowest dissociation scores (mean score, 14.8). The findings underline the importance of careful psychopathological assessment of dissociative symptoms in the entire range of mental disorders.

  15. Aged anthropogenic iodine in a boreal peat bog

    International Nuclear Information System (INIS)

    Maillant, S.; Sheppard, M.I.; Denys, S.; Leclerc Cessac, E.

    2004-01-01

    Iodine-129 is a radionuclide of major concern in the international safety assessments for deep geological storage and disposal of nuclear waste because it migrates quickly through the geosphere to the biosphere and then from the soil to humans through the food-chain. However, in organic soils the 129 I may be immobilized over a long time period, and so these soils represent a potential accumulation point in the biosphere. Effects of long residence times of iodine in soils are scarce. The present paper gives some insight on the aging of stable iodine, under natural conditions. Stable iodine was introduced as KI in 1987 at the base of a small natural sphagnum bog to simulate arrival of iodine via a groundwater discharge from the geosphere. Previous data revealed the spread of the iodine outwards spatially from the basal spike and also recorded its rise towards the bog surface. Fifteen years later, the groundwater, the soil and the vegetation have been sampled and analyzed for iodine. The results we will present give insight on the mobility of 'aged' iodine with time, the retention properties of the peat, and provide iodine transfer factors for native boreal plant species. The data show iodine: - continues to slowly spread from the spike after 15 years, - is more strongly retained on the solid phase at the surface than at depth, - the chemical structure of the peat may influence the retention of iodine as shown by NMR analysis, - iodine retention has become greater with time, and - herbaceous species are the greatest accumulators. This study demonstrates bogs present good sinks for iodine and limit the transfer of iodine to some of the 'wildlife' food-chains. (author)

  16. Effect of excess iodine intake on thyroid on human health.

    Science.gov (United States)

    Koukkou, Eftychia G; Roupas, Nikolaos D; Markou, Kostas B

    2017-04-01

    The recommended daily intake of iodide, is 150 μg for adolescents and adults, 250 μg for pregnancy and lactation. Thyroid gland is an effective collector of iodine. The active iodine uptake along the basolateral membrane of thyroid cell is followed by its transport to the apical edge of the cell and then to the follicle lumen. TSH acts through cAMP and stimulates NIS gene expression and protein synthesis. The major proportion of iodine in the thyroid gland is bound to Thyroglobulin. The non-organic intrathyroidal iodine is usually low, but significantly greater compared to plasma. Large doses of iodine reduce both the uptake and the organification (Wolff-Chaikoff effect) and cause partial inhibition of Tg proteolysis. The thyroid gland has several protective mechanisms resulting on the maintenance of normal thyroid function despite wide fluctuations of the daily iodine intake. Ingestion of several commonly used drugs and food conservatives results in acute or chronic excessive iodine intake. Failure to escape from the iodine induced organification inhibition can cause hypothyroidism, which is temporary and subsides after iodine exposure ceases. Iodine excess may also establish a status of excessive thyroid hormone synthesis and release, thus inducing autonomic thyroid function in iodopenic areas or can contribute to the development of iodine-induced hyperthyroidism in iodine abundant areas. The anti-arrhythmic Amiodarone, is a benzofuranic product with a very high iodine content, is associated with either hypo- or hyperthyroidism development. In the presence of defective auto-protective mechanisms, excessive iodine ingestion can divert the normal thyroid function.

  17. Iodine uptake and distribution in horticultural and fruit tree species

    Directory of Open Access Journals (Sweden)

    Alessandra Caffagni

    2012-07-01

    Full Text Available Iodine is an essential microelement for humans and iodine deficiency disorder (IDD is one of the most widespread nutrient-deficiency diseases in the world. Iodine biofortification of plants provides an attractive opportunity to increase iodine intake in humans and to prevent and control IDD. This study was conducted to investigate the iodine uptake and accumulation in edible portion of two fruit trees: plum and nectarine, and two horticultural crops: tomato and potato. Two type of iodine treatments (soil and foliar spray application, and, for fresh market tomato, two production systems (open field and greenhouse hydroponic culture were tested. The distribution of iodine in potato stem and leaves, and in plum tree fruits, leaves, and branches was investigated. Iodine content of potato tubers after postharvest storage and processing (cooking, and iodine content of nectarine fruits after postharvest storage and processing (peeling were also determined. Differences in iodine accumulation were observed among the four crops, between applications, and between production systems. In open field, the maximum iodine content ranged from 9.5 and 14.3 μg 100 g−1 for plum and nectarine fruit, to 89.4 and 144.0 μg 100 g−1 for potato tuber and tomato fruit, respectively. These results showed that nectarine and plum tree accumulated significantly lower amounts of iodine in their edible tissues, in comparison with potato and tomato. The experiments also indicated hydroponic culture as the most efficient system for iodine uptake in tomato, since its fresh fruits accumulated up to 2423 μg 100 g−1 of iodine. Iodine was stored mainly in the leaves, in all species investigated. Only a small portion of iodine was moved to plum tree branches and fruits, and to potato stems and tubers. No differences in iodine content after fruit peeling was observed. A significant increase in iodine content of potato was observed after baking, whereas a significant decrease was

  18. Dynamic nano-pulling effect of the boron-functionalized graphene monovacancy for molecule dissociation

    International Nuclear Information System (INIS)

    Wang, Xiao-Chun; Liu, Fu-Chun; Feng, Wei; Zhang, Yong; Ma, Yanming; Zhang, Sean Xiao-An

    2013-01-01

    We investigate the molecule dissociation and separation roles of graphene membranes with different functionalized monovacancies using first-principles density functional theory calculations. We have found that the boron-functionalized graphene vacancy can effectively dissociate one H 2 molecular into two hydrogen atoms through a novel nano-pulling effect; at the same time it can separate the two hydrogen atoms on different sides of the graphene monolayer, with about 0.21 eV net adsorption energy. The boron-functionalized monovacancy acts like a pair of nanoscissors in this process. The binding energies of the two separated hydrogen atoms with the boron-functionalized monovacancy are 2.82 eV and 1.54 eV, respectively, in the two releasing steps. The boron-functionalized graphene monovacancy as a molecular dissociator can remarkably decrease the potential barrier of H 2 dissociation compared to that of 4.58 eV for free H 2 molecules. This method may open up new avenues for the development of safe hydrogen storage and biomimic photosynthesizers. (paper)

  19. Assessing iodine intake, iodine status, and the effects of maternal iodine supplementation: introduction to articles arising from 3 workshops held by the NIH Office of Dietary Supplements12

    Science.gov (United States)

    Ershow, Abby G; Coates, Paul M; Swanson, Christine A

    2016-01-01

    The NIH Office of Dietary Supplements (ODS) convened 3 workshops on iodine nutrition in 2014, each held in Rockville, Maryland. These workshops were part of the ongoing ODS Iodine Initiative, begun in 2011 in response to concerns that US pregnant women may be at risk of iodine deficiency and that a high fraction of prenatal dietary supplements do not contain the recommended amounts of iodine. The primary purpose of the workshops was to consider the data and resources necessary to evaluate the clinical and public health benefits and risks of maternal iodine supplementation in the United States. The first workshop focused on the assessment of iodine intake, the second focused on the assessment of iodine status, and the third focused on the design and interpretation of clinical trials of maternal iodine supplementation. Here we provide the background of the ODS Iodine Initiative, summarize the 3 workshops held in 2014, and introduce the articles that arose from the workshops and are published in this supplement issue. PMID:27534646

  20. Dissociative recombination of molecular ions H2+

    International Nuclear Information System (INIS)

    Abarenov, A.V.; Marchenko, V.S.

    1989-01-01

    The total cross sections of dissociation and dissociative recombination of slow electrons and molecular ions H 2 + have been calculated in terms of the quasiclassical and dipole approximations. In the calculations allowance was made for the quantum nature of vibrational motion of heavy particles and presence of autoionization of divergence states of the H 2 (Σ u , nl) molecules. It is shown that the H 2 + ion dissociation cross sections are dominant in increase of the electron energy in the ε >or approx. 2-3 eV region for H 2 + (v) ion distribution over the vibrational levels characteristic for the beam experiments. 15 refs.; 5 figs

  1. Dissociative identity disorder: a controversial diagnosis.

    Science.gov (United States)

    Gillig, Paulette Marie

    2009-03-01

    A brief description of the controversies surrounding the diagnosis of dissociative identity disorder is presented, followed by a discussion of the proposed similarities and differences between dissociative identity disorder and borderline personality disorder. The phenomenon of autohypnosis in the context of early childhood sexual trauma and disordered attachment is discussed, as is the meaning of alters or alternate personalities. The author describes recent neurosciences research that may relate the symptoms of dissociative identity disorder to demonstrable disordered attention and memory processes. A clinical description of a typical patient presentation is included, plus some recommendations for approaches to treatment.

  2. Physical adsorption and molecular dynamics

    International Nuclear Information System (INIS)

    Cohan, N.V.

    1981-01-01

    Some aspects of noble gases adsorption (except He) on graphite substracts are reviewed. Experimental results from this adsorption are analyzed and compared with molecular dynamics calculations. (L.C.) [pt

  3. Values of iodine metabolism biomarkers in assessing the iodine nutrition status in surgically treated patients with thyroid disease.

    Science.gov (United States)

    Han, Jian-hua; Wu, Lian; Yu, Song-lin; Fang, Hui-ling; Kamg, Wei-ming; Cheng, Xin-qi; Lu, Jie; Yu, Jian-chun; Qiu, Ling

    2015-04-01

    To assess the clinical application value of iodine metabolism biomarkers in assessing iodine nutrition status in surgically treated patients with thyroid disease. Blood,morning urine and 24-hour urine samples were collected in 31 healthy volunteers and in 30 surgically treated patients with thyroid disease before and after surgery. Iodine concentration was analyzed by inductively coupled plasma mass spectrometry. The iodine metabolism biomarkers including serum iodine (SI), morning urine iodine(UI), morning urine iodine/urine creatinine ratio (UI/UCr), 24-hour urine iodine (24 h UI), and 24-hour urine iodine excretion (24 h UIE) were evaluated in these two groups. In addition, the validation coincidence rate of iodine metabolism biomarkers in healthy volunteers to different reference ranges including World Health Organization, Mayo Clinic, and Quest Diagnostics were calculated. The UI/UCr ratio of pre-operative thyroid disease patients was significantly lower than that of healthy volunteers (P0.05) between these two groups. The SI, UI ,and 24 h UI in postoperative thyroid disease patients were significantly higher than those of the pre-operative patients (all Piodine metabolism biomarkers. The UI/UCr ratio may be used for iodine nutrition evaluation in surgically treated patients with thyroid disease.

  4. Methane dissociation on the steps and terraces of Pt(211) resolved by quantum state and impact site

    Science.gov (United States)

    Chadwick, Helen; Guo, Han; Gutiérrez-González, Ana; Menzel, Jan Paul; Jackson, Bret; Beck, Rainer D.

    2018-01-01

    Methane dissociation on the step and terrace sites of a Pt(211) single crystal was studied by reflection absorption infrared spectroscopy (RAIRS) at a surface temperature of 120 K. The C—H stretch RAIRS signal of the chemisorbed methyl product species was used to distinguish between adsorption on step and terrace sites allowing methyl uptake to be monitored as a function of incident kinetic energy for both sites. Our results indicate a direct dissociation mechanism on both sites with higher reactivity on steps than on terraces consistent with a difference in an activation barrier height of at least 30 kJ/mol. State-specific preparation of incident CH4 with one quantum of antisymmetric (ν3) stretch vibration further increases the CH4 reactivity enabling comparison between translational and vibrational activation on both steps and terraces. The reaction is modeled with first principles quantum theory that accurately describes dissociative chemisorption at different sites on the surface.

  5. Direct evidence for coastal iodine particles from Laminaria macroalgae – linkage to emissions of molecular iodine

    Directory of Open Access Journals (Sweden)

    G. McFiggans

    2004-01-01

    Full Text Available Renewal of ultrafine aerosols in the marine boundary layer may lead to repopulation of the marine distribution and ultimately determine the concentration of cloud condensation nuclei (CCN. Thus the formation of nanometre-scale particles can lead to enhanced scattering of incoming radiation and a net cooling of the atmosphere. The recent demonstration of the chamber formation of new particles from the photolytic production of condensable iodine-containing compounds from diiodomethane (CH2I2, (O'Dowd et al., 2002; Kolb, 2002; Jimenez et al., 2003a; Burkholder and Ravishankara, 2003, provides an additional mechanism to the gas-to-particle conversion of sulphuric acid formed in the photo-oxidation of dimethylsulphide for marine aerosol repopulation. CH2I2 is emitted from seaweeds (Carpenter et al., 1999, 2000 and has been suggested as an initiator of particle formation. We demonstrate here for the first time that ultrafine iodine-containing particles are produced by intertidal macroalgae exposed to ambient levels of ozone. The particle composition is very similar both to those formed in the chamber photo-oxidation of diiodomethane and in the oxidation of molecular iodine by ozone. The particles formed in all three systems are similarly aspherical. When small, those formed in the molecular iodine system swell only moderately when exposed to increased humidity environments, and swell progressively less with increasing size; this behaviour occurs whether they are formed in dry or humid environments, in contrast to those in the CH2I2 system. Direct coastal boundary layer observations of molecular iodine, ultrafine particle production and iodocarbons are reported. Using a newly measured molecular iodine photolysis rate, it is shown that, if atomic iodine is involved in the observed particle bursts, it is of the order of at least 1000 times more likely to result from molecular iodine photolysis than diiodomethane photolysis. A hypothesis for molecular

  6. Direct evidence for coastal iodine particles from Laminaria macroalgae - linkage to emissions of molecular iodine

    Science.gov (United States)

    McFiggans, G.; Coe, H.; Burgess, R.; Allan, J.; Cubison, M.; Alfarra, M. R.; Saunders, R.; Saiz-Lopez, A.; Plane, J. M. C.; Wevill, D.; Carpenter, L.; Rickard, A. R.; Monks, P. S.

    2004-05-01

    Renewal of ultrafine aerosols in the marine boundary layer may lead to repopulation of the marine distribution and ultimately determine the concentration of cloud condensation nuclei (CCN). Thus the formation of nanometre-scale particles can lead to enhanced scattering of incoming radiation and a net cooling of the atmosphere. The recent demonstration of the chamber formation of new particles from the photolytic production of condensable iodine-containing compounds from diiodomethane (CH2I2), (O'Dowd et al., 2002; Kolb, 2002; Jimenez et al., 2003a; Burkholder and Ravishankara, 2003), provides an additional mechanism to the gas-to-particle conversion of sulphuric acid formed in the photo-oxidation of dimethylsulphide for marine aerosol repopulation. CH2I2 is emitted from seaweeds (Carpenter et al., 1999, 2000) and has been suggested as an initiator of particle formation. We demonstrate here for the first time that ultrafine iodine-containing particles are produced by intertidal macroalgae exposed to ambient levels of ozone. The particle composition is very similar both to those formed in the chamber photo-oxidation of diiodomethane and in the oxidation of molecular iodine by ozone. The particles formed in all three systems are similarly aspherical. When small, those formed in the molecular iodine system swell only moderately when exposed to increased humidity environments, and swell progressively less with increasing size; this behaviour occurs whether they are formed in dry or humid environments, in contrast to those in the CH2I2 system. Direct coastal boundary layer observations of molecular iodine, ultrafine particle production and iodocarbons are reported. Using a newly measured molecular iodine photolysis rate, it is shown that, if atomic iodine is involved in the observed particle bursts, it is of the order of at least 1000 times more likely to result from molecular iodine photolysis than diiodomethane photolysis. A hypothesis for molecular iodine release from

  7. Iodine Deficiency: Where Are We Now? (Efficiency of Belarusian Strategy in Elimination of Iodine Deficiency: 15-year Experience

    Directory of Open Access Journals (Sweden)

    Т.V. Mokhort

    2015-03-01

    Full Text Available Between the former Soviet republics, which became independent states, there are big differences in the state of iodine provision and in technology to eliminate iodine deficiency in the diet of the population. The publication presents a strategy for the elimination of iodine deficiency, developed and implemented in the Republic of Belarus in order to achieve an adequate level of iodine nutrition in the state. In the Republic of Belarus, 94 % of salt consumption is iodized salt that ensures adequate iodine intake, confirmed by urinary iodine excretion (median 169 mcg/l. The effectiveness of the model for iodine prophylaxis used in Belarus and based on the widespread use of iodized salt in the food industry gives reason to recommend this model for implementation in other countries.

  8. Radical-mediated adsorption: Ozone oxidation of passivated silicon

    Science.gov (United States)

    Fink, Christian K.; Jenkins, Stephen J.

    2008-07-01

    We report first-principles molecular dynamics calculations on the initial oxidation of hydrogen-passivated Si{0 0 1} by ozone (O 3). We observe an intriguing radical-mediated adsorption mechanism, archetypal of a class not reported in the literature so far. Singlet ozone abstracts one hydrogen atom to form a short-lived hydrotrioxy radical (HO3rad ), before dissociating into surface hydroxyl ( sbnd OH) and gas-phase O 2. Vibrational and electronic analysis of the hydrotrioxy species confirms the genuine radical nature of the reaction intermediate.

  9. Role of nonlocal exchange correlation in activated adsorption

    DEFF Research Database (Denmark)

    Hammer, Bjørk; Jacobsen, Karsten Wedel; Nørskov, Jens Kehlet

    1993-01-01

    The barrier for dissociative adsorption of H-2 on Al(110) has been calculated within the generalized gradient approximation. A pronounced increase of the barrier height is found compared with what is calculated in the local density approximation (LDA). The apparent LDA underestimation...... of the barrier height is shown to be intimately linked with the LDA underbinding of core electrons and we suggest it to be a general phenomenon not limited to the particular nonlocal exchange-correlation approximation used or the particular system studied....

  10. Hydrogen adsorption on palladium and palladium hydride at 1 bar

    DEFF Research Database (Denmark)

    Johansson, Martin; Skulason, Egill; Nielsen, Gunver

    2010-01-01

    The dissociative sticking probability for H-2 on Pd films supported on sputtered Highly Ordered Pyrolytic Graphite (HOPG) has been derived from measurements of the rate of the H-D exchange reaction at 1 bar. The sticking probability for H-2, S. is higher on Pd hydride than on Pd (a factor of 1...... strongly to Pd hydride than to Pd. The activation barrier for desorption at a H coverage of one mono layer is slightly lower on Pd hydride, whereas the activation energy for adsorption is similar on Pd and Pd hydride. It is concluded that the higher sticking probability on Pd hydride is most likely caused...

  11. Adsorption and Oxidation Investigations over Pt/Al2O3 Catalyst: A Microcalorimetric Study

    Directory of Open Access Journals (Sweden)

    Oana Mihai

    2016-05-01

    Full Text Available The differential adsorption heats of oxygen and NO, as well as catalytic oxidation behavior during NO oxidation and NO2 dissociation reactions over supported Pt-catalysts, were investigated by microcalorimetric measurements. The average heat of adsorption (∆H of oxygen ranged from 310 kJ/mol at 200 °C to 289 kJ/mol at 400 °C. Over this temperature range formation of platinum oxides and coverage dependence caused variations in the apparent heat of adsorption. NO heat of adsorption from 50 to 150 °C was near constant with an average value of 202 kJ/mol over the temperature range.

  12. Adsorption of small NaCl clusters on surfaces of silicon nanostructures

    International Nuclear Information System (INIS)

    Amsler, Maximilian; Alireza Ghasemi, S; Goedecker, Stefan; Neelov, Alexey; Genovese, Luigi

    2009-01-01

    We have studied possible adsorption geometries of neutral NaCl clusters on the disordered surface of a large silicon model tip used in non-contact atomic force microscopy. The minima hopping method was used to determine low energy model tip configurations as well as ground state geometries of isolated NaCl clusters. The combined system was treated with density functional theory. Alkali halides have proven to be strong structure seekers and tend to form highly stable ground state configurations whenever possible. The favored adsorption geometry for four Na and four Cl atoms was found to be an adsorption of four NaCl dimers due to the formation of Cl-Si bonds. However, for larger NaCl clusters, the increasing energy required to dissociate the cluster into NaCl dimers suggests that adsorption of whole clusters in their isolated ground state configuration is preferred.

  13. Thiolate adsorption on Au({{hkl}}) and equilibrium shape of large thiolate-covered gold nanoparticles

    Science.gov (United States)

    Barmparis, Georgios D.; Honkala, Karoliina; Remediakis, Ioannis N.

    2013-02-01

    The adsorption of thiolates on Au surfaces employing density-functional-theory calculations has been studied. The dissociative chemisorption of dimethyl disulfide (CH3S-SCH3) on 14 different Au(hkl) is used as a model system. We discuss trends on adsorption energies, bond lengths, and bond angles as the surface structure changes, considering every possible Au(hkl) with h, k, l ⩽ 3 plus the kinked Au(421). Methanethiolate (CH3S-) prefers adsorption on bridge sites on all surfaces considered; hollow and on top sites are highly unfavourable. The interface tensions for Au(hkl)-thiolate interfaces is determined at low coverage. Using the interface tensions in a Wulff construction method, we construct atomistic models for the equilibrium shape of large thiolate-covered gold nanoparticles. Gold atoms in a nanoparticle change their equilibrium positions upon adsorption of thiolates towards shapes of higher sphericity and higher concentration of step-edge atoms.

  14. Site competition on metal surfaces: an electron spectroscopic study of sequential adsorption on W(110)

    International Nuclear Information System (INIS)

    Steinkilberg, M.; Menzel, D.

    1977-01-01

    Using UPS and XPS, the sequential adsorption of hydrogen + carbon monoxide, and of hydrogen + oxygen, on W(110) has been studied at room temperature. Adsorption of CO on a H-covered surface is rapid and leads to total displacement of hydrogen. The resulting CO layer however, is different from that formed on the clean surface under identical conditions, in that it consists of a higher percentage of virgin CO, while considerably more β-CO forms on the clean surface. Oxygen does not adsorb on a H-covered surface, nor displace hydrogen. It is concluded that hydrogen most probably occupies the same sites utilized by dissociative adsorption of CO and oxygen, while virgin CO can also occupy different sites; its adsorption can thus lead to interactional weakening of the H-surface bond. (Auth.)

  15. Adsorption in cryogenics

    International Nuclear Information System (INIS)

    Ravex, A.

    1989-01-01

    There are two main fields for application of physical adsorption in cryogenics: cryopumping and refrigeration. Cryopumping has known many developments but is now almost industrial. Basic principles, applications and realizations are presented, for instance, in nuclear fusion and particle physics. For refrigeration developments and realizations are rare but present potential space applications [fr

  16. The cognitive psychology of dissociative states.

    Science.gov (United States)

    Brown, Richard J

    2002-08-01

    A number of theoretical models have identified dissociation as a possible cognitive mechanism underlying medically unexplained symptoms (''hysteria''). A review of research and theory in this area indicates that the dissociation concept is a useful explanation of this phenomenon. However, existing models of dissociation have a number of explanatory shortcomings. This article describes a recent model of unexplained illness that aims to extend the dissociation concept by reference to research and theory from contemporary cognitive psychology. According to this view, unexplained symptoms should be regarded as disturbances of consciousness and behavioural control, resulting from the chronic activation of stored symptom representations within memory. This process is driven by the repeated reallocation of high-level attention on to symptom representations. The model offers a fresh perspective on the nature of unexplained symptoms, providing an explicit account of the factors involved in the creation and maintenance of this phenomenon.

  17. The co-occurrence of PTSD and dissociation: differentiating severe PTSD from dissociative-PTSD.

    Science.gov (United States)

    Armour, Cherie; Karstoft, Karen-Inge; Richardson, J Don

    2014-08-01

    A dissociative-posttraumatic stress disorder (PTSD) subtype has been included in the DSM-5. However, it is not yet clear whether certain socio-demographic characteristics or psychological/clinical constructs such as comorbid psychopathology differentiate between severe PTSD and dissociative-PTSD. The current study investigated the existence of a dissociative-PTSD subtype and explored whether a number of trauma and clinical covariates could differentiate between severe PTSD alone and dissociative-PTSD. The current study utilized a sample of 432 treatment seeking Canadian military veterans. Participants were assessed with the Clinician Administered PTSD Scale (CAPS) and self-report measures of traumatic life events, depression, and anxiety. CAPS severity scores were created reflecting the sum of the frequency and intensity items from each of the 17 PTSD and 3 dissociation items. The CAPS severity scores were used as indicators in a latent profile analysis (LPA) to investigate the existence of a dissociative-PTSD subtype. Subsequently, several covariates were added to the model to explore differences between severe PTSD alone and dissociative-PTSD. The LPA identified five classes: one of which constituted a severe PTSD group (30.5 %), and one of which constituted a dissociative-PTSD group (13.7 %). None of the included, demographic, trauma, or clinical covariates were significantly predictive of membership in the dissociative-PTSD group compared to the severe PTSD group. In conclusion, a significant proportion of individuals report high levels of dissociation alongside their PTSD, which constitutes a dissociative-PTSD subtype. Further investigation is needed to identify which factors may increase or decrease the likelihood of membership in a dissociative-PTSD subtype group compared to a severe PTSD only group.

  18. Leak test method and test device for iodine filter

    International Nuclear Information System (INIS)

    Fukasawa, Tetsuo; Funabashi, Kiyomi; Miura, Noboru; Miura, Eiichi.

    1995-01-01

    An air introduction device which can change a humidity is disposed upstream of an iodine filter to be tested, and a humidity measuring device is disposed downstream of the iodine filter respectively. At first, dried air reduced with humidity is flown from the air introduction device to the iodine filter, to remove moisture content from an iodine adsorber in the iodine filter. Next, air at an increased humidity is supplied to the iodine filter. The difference between the time starting the supply of the highly humid air and the time detecting the high humidity at the humidity measuring device is measured. When the time difference is smaller than the time difference measured previously in a normal iodine filter, it shows the presence of leak in the iodine filter to be tested. With such procedures, leakage in the iodine filter which removes radioactive iodine from off-gases discharged from the radioactive material handling facilities can be detected easily by using water (steams), namely, a naturally present material. (I.N.)

  19. Stability of added iodine in processed cereal foods.

    Science.gov (United States)

    Thomson, B M

    2009-01-01

    The stability of iodine from iodized salt was measured in white bread, grain bread, sweet biscuits and the breakfast cereals, Weetbix (a flaked, pressed, wheat product), Ricies (a puffed rice product) and toasted muesli, as part of the New Zealand Government's initiatives to address the public health issue of low iodine intake by most New Zealanders. Triplicate runs of each product were manufactured by commercial food manufacturers between September 2006 and May 2007 with iodized and non-iodized salt. Triplicate samples were taken at various steps during processing of each food and analysed for moisture and iodine content. Iodine concentration was determined by inductively coupled plasma-mass spectrometry following an alkaline digestion. Iodine, at the equivalent of 25-65 mg of iodine per kg salt, was 100% retained in each of the selected foods from the time of mixing to the final product. These results imply that all iodine added via salt at the time of manufacture is available for consumption but not necessarily bioavailable. These data can be used for modelling the impact of strategies to increase iodine exposure. Salt as an ingredient is not a good predictor of iodine intake due to the inhomogeneity of iodine in iodized salt.

  20. Iodine Nutritional Status of School Children in Nauru 2015

    Directory of Open Access Journals (Sweden)

    Chun-Jui Huang

    2016-08-01

    Full Text Available Little is known about iodine nutritional status in island countries in the Pacific Ocean. The primary objective of this study was to report for the first time the iodine nutritional status of people in Nauru. In addition, sources of iodine nutrition (i.e., water and salt were investigated. A school-based cross-sectional survey of children aged 6–12 years was conducted in three primary schools of Nauru. Urinary iodine concentration (UIC was determined by spot urine samples. Available water and salt samples in Nauru were collected for the measurement of iodine content. A food frequency questionnaire was conducted. The median UIC was 142 μg/L, and 25.2% and 7.4% of the population had median UIC below 100 μg/L and 50 μg/L, respectively. Natural iodine-containing foods such as seaweeds and agar were rare. Iodine was undetectable in Nauruan tank water, filtered tap water, and raindrops. Of the analyzed salt products, five kinds were non-iodized, and three were iodized (iodine content: 15 ppm, 65 ppm, and 68 ppm, respectively. The results indicate that the iodine status in Nauruan school children is adequate. Iodized salt may serve as an important source of iodine nutrition in Nauru.