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Sample records for mercuric iodide detectors

  1. Radiation damage resistance in mercuric iodide X-ray detectors

    Energy Technology Data Exchange (ETDEWEB)

    Patt, B E; Dolin, R C; Devore, T M; Markakis, J M [EG and G Energy Measurements, Inc., Goleta, CA (USA); Iwanczyk, J S; Dorri, N [Xsirius, Inc., Marina del Rey, CA (USA); Trombka, J [National Aeronautics and Space Administration, Greenbelt, MD (USA). Goddard Space Flight Center

    1990-12-20

    Mercuric iodide (HgI{sub 2}) radiation detectors show great potential as ambient-temperature solid-state detectors for X-rays, gamma rays and visible light, with parameters that are competitive with existing technologies. In a previous experiment, HgI{sub 2} detectors irradiated with 10 MeV protons/cm{sup 2} exhibited no damage. The 10 MeV protons represent only the low range of the spectrum of energies that are important. An experiment has been conducted at the Saturne accelerator facility at Saclay, France, to determine the susceptibility of these detectors to radiation damage by high-energy (1.5 GeV) protons. The detectors were irradiated to a fluence of 10{sup 8} protons/cm{sup 2}. This fluence is equivalent to the cosmic radiation expected in a one-year period in space. The resolution of the detectors was measured as a function of the integral dose. No degradation in the response of any of the detectors or spectrometers was seen. It is clear from this data that HgI{sub 2} has extremely high radiation-damage resistance, exceeding that of most other semiconductor materials used for radiation detectors. Based on the results shown to date, HgI{sub 2} detectors are suitable for applications in which they may be exposed to high integral dose levels. (orig.).

  2. Mercuric iodide sensor technology

    International Nuclear Information System (INIS)

    James, R.B.; Anderson, R.J.; Schlesinger, T.E.

    1996-09-01

    This report describes the improvement in the performance and the manufacturing yield of mercuric iodide detectors achieved by identifying the dominant impurities, carrier traps, and processing steps limiting device performance. Theoretical studies of electron and hole transport in this material set fundamental limits on detector performance and provided a standard against which to compare experimental results. Spectroscopy techniques including low temperature photoluminescence and thermally stimulated current spectroscopy were applied to characterize the deep level traps in this material. Traps and defects that can be introduced into the detector during growth, from the contact, and during the various steps in detector fabrication were identified. Trap energy levels and their relative abundances were determined. Variations in material quality and detector performance at the micron scale were investigated to understand the distribution in electric field in large volume detectors suitable for gamma-ray spectroscopy. Surface aging and contact degradation was studied extensively by techniques including atomic force microscopy, transmission electron microscopy, and variable angle spectroscopic ellipsometry. Preferred handling and processing procedures for maximizing detector performance and yield were established. The manufacturing yield of high resolution gamma-ray detectors was improved from a few percent to more than 30%

  3. Mercuric iodide semiconductor detectors encapsulated in polymeric resin

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Joao F. Trencher; Santos, Robinson A. dos; Ferraz, Caue de M.; Oliveira, Adriano S.; Velo, Alexandre F.; Mesquita, Carlos H. de; Hamada, Margarida M., E-mail: mmhamada@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Disch, Christian; Fiederle, Michael [Albert-Ludwigs Universität Freiburg - UniFreibrug, Freiburg Materials Research Center - FMF, Freiburg (Germany)

    2015-07-01

    The development of new semiconductor radiation detectors always finds many setback factors, such as: high concentration of impurities in the start materials, poor long term stability, the surface oxidation and other difficulties discussed extensively in the literature, that limit their use. In this work was studied, the application of a coating resin on HgI2 detectors, in order to protect the semiconductor crystal reactions from atmospheric gases and to isolate electrically the surface of the crystals. Four polymeric resins were analyzed: Resin 1: 50% - 100%Heptane, 10% - 25% methylcyclohexane, <1% cyclohexane; Resin 2: 25% - 50% ethanol, 25% - 50% acetone, <2,5% ethylacetate; Resin 3: 50% - 100% methylacetate, 5% - 10% n-butylacetate; Resin 4: 50% - 100% ethyl-2-cyanacrylat. The influence of the polymeric resin type used on the spectroscopic performance of the HgI{sub 2} semiconductor detector is, clearly, demonstrated. The better result was found for the detector encapsulated with Resin 3. An increase of up to 26 times at the stability time was observed for the detectors encapsulated compared to that non-encapsulated detector. (author)

  4. Performance of room temperature mercuric iodide (HgI2) detectors in the ultra low energy x-ray region

    International Nuclear Information System (INIS)

    Dabrowski, A.J.; Iwanczyk, J.S.; Barton, J.B.; Huth, G.C.; Whited, R.; Ortale, C.; Economou, T.E.; Turkevich, A.L.

    1980-01-01

    Performance of room temperature mercuric iodide x-ray spectrometers has been recently improved through new fabrication techniques and further development of low noise associated electronic systems. This progress has extended the range of measurements to the ultra low energy x-ray region at room temperature. This paper reports the study of the effect of contact material on the performance of HgI 2 detectors in the low energy x-ray region

  5. Mercuric iodide room-temperature array detectors for gamma-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Patt, B. [Xsirius, Inc, Camarillo, CA (United States)

    1994-11-15

    Significant progress has been made recently in the development of mercuric iodide detector arrays for gamma-ray imaging, making real the possibility of constructing high-performance small, light-weight, portable gamma-ray imaging systems. New techniques have been applied in detector fabrication and then low noise electronics which have produced pixel arrays with high-energy resolution, high spatial resolution, high gamma stopping efficiency. Measurements of the energy resolution capability have been made on a 19-element protypical array. Pixel energy resolutions of 2.98% fwhm and 3.88% fwhm were obtained at 59 keV (241-Am) and 140-keV (99m-Tc), respectively. The pixel spectra for a 14-element section of the data is shown together with the composition of the overlapped individual pixel spectra. These techniques are now being applied to fabricate much larger arrays with thousands of pixels. Extension of these principles to imaging scenarios involving gamma-ray energies up to several hundred keV is also possible. This would enable imaging of the 208 keV and 375-414 keV 239-Pu and 240-Pu structures, as well as the 186 keV line of 235-U.

  6. Introduction to fifth international workshop on mercuric iodide nuclear radiation detectors

    International Nuclear Information System (INIS)

    Schieber, M.

    1982-01-01

    Mercuric iodide is a wide bandgap semiconductor, with Eg approx. = 2.14 eV at room temperature. Therefore, HgI 2 is totally different from the well-studied, narrower gap, elemental semiconductors such as Si and Ge, and also different in its physical and chemical properties from the known semiconductor binary zinc-blend compounds such as GaAs or InP. The purpose of studies in the last decade was to further our understanding of HgI 2 ; recent progress is reported

  7. Advanced radiation detector development mercuric iodide, silicon with internal gain, hybrid scintillator/semiconductor detectors. Comprehensive summary report, 1976-1985

    International Nuclear Information System (INIS)

    Huth, G.C.; Dabrowski, A.J.

    1985-01-01

    Accomplishments are reported in the development of a compound semi-insulator mercuric iodide (HgI 2 ) for nuclear radiation detection and spectroscopy, early lung cancer detection and localization in the uranium miner/worker population, computer digital image processing and image reconstruction research, and a concept for multiple, filtered x-ray computed tomography scanning to reveal chemical compositional information. Another area of interest is the study of new advances in the area of silicon detectors with internal gain (''avalanche'')

  8. Mercuric Iodide Anticoincidence Shield for Gamma-Ray Spectrometer, Phase I

    Data.gov (United States)

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

  9. Mercuric Iodide Anticoincidence Shield for Gamma-Ray Spectrometer, Phase II

    Data.gov (United States)

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

  10. Study of low noise preamplifier systems for use with room temperature mercuric iodide (HgI2) x-ray detectors

    International Nuclear Information System (INIS)

    Iwanczyk, J.S.; Dabrowski, A.J.; Huth, G.C.; Del Duca, A.; Schenpple, W.

    1980-01-01

    An analysis of different preamplification systems for use with room temperature mercuric iodide x-ray detectors has been performed. Resistor-, drain-, and light-feedback preamplifiers have been studied. Energy resolution of 295 eV (FWHM) for Fe-55 source (5.9 keV) and 225 eV (FWHM) for the pulser have been obtained with both the detector and the input FET at room temperature using the pulsed-light feedback preamplifier. It has been shown that cooling the input FET using a small Peltier element allows the energy resolution to be improved up to 25%

  11. Developments in mercuric iodide gamma ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Patt, B E; Beyerle, A G; Dolin, R C; Ortale, C [EG and G Energy Measurements, Inc., Goleta, CA (USA). Santa Barbara Operations

    1989-11-01

    A mercuric iodide (HgI{sub 2}) gamma ray imaging array and camera system previously described have been characterized for spatial and energy resolution. Based on these data a new camera is being developed to more fully exploit the potential of the array. Characterization results and design criteria for the new camera will be presented. (orig.).

  12. Development of advanced solid state radiation detectors: mercuric iodide and high gain silicon avalanche structures. Annual progress report, December 1, 1984-November 30, 1985

    International Nuclear Information System (INIS)

    Huth, G.C.; Dabrowski, A.J.

    1986-04-01

    This report covers the period from December 1984 through November 1985 for this research project sponsored by the Office of Health and Environmental Research of the Dept. of Energy. This work has two primary research objectives. The first is continuing development of the material mercuric iodide (HgI 2 ) and its applications to energy dispersive x-ray analysis and gamma ray spectrometry. The second task involves investigation of silicon ''avalanche'' (internal electron gain) radiation detector structures fabricated from new neutron transmutation doped (NTD) silicon single crystal

  13. Growth of mercuric iodide single crystals from dimethylsulfoxide

    International Nuclear Information System (INIS)

    Carlston, R.C.

    1976-01-01

    Dimethylsulfoxide is used as a solvent for the growth of red mercuric iodide (HgI 2 ) crystals for use in radiation detectors. The hygroscopic property of the solvent allows controlled amounts of water to enter into the solvent phase and diminish the large solubility of HgI 2 so that the precipitating solid collects as well-defined euhedral crystals which grow into a volume of several cc

  14. Electrical and photomechanical effects of plastic deformation of mercuric iodide

    International Nuclear Information System (INIS)

    Marschall, J.; Milstein, F.; Gerrish, V.

    1991-01-01

    The effects of bulk plastic deformation of mercuric iodide (HgI 2 ), upon some of the electronic properties relevant to the performance of HgI 2 as a radiation detector were examined experimentally. Hole lifetimes, as well as hole and electron mobilities, were measured at various stages of sample deformation. Hole lifetimes were found to decrease by a factor of 2 under strains of several percent; carrier mobilities varied within experimental error, except during creep loading where electron and hole mobilities decreased by about 65 % and 25 %, respectively. Additionally, dark current measurements were made on specimens with varying degrees of accumulated plastic damage caused by c plane shear. Dark current values did not strongly reflect the extent of bulk plastic damage in deformed specimens. 16 refs., 4 figs., 1 tab

  15. Red mercuric iodide crystals obtained by isothermal solution evaporation: Characterization for mammographic X-ray imaging detectors

    Energy Technology Data Exchange (ETDEWEB)

    Caldeira, A.M.F.; Ugucioni, J.C.; Mulato, M.

    2014-02-11

    Millimeter-sized mercury iodide crystals were obtained by the isothermal evaporation technique using dimethylformamide (DMF), diethyl-ether/DMF mixture and THF. Different concentrations (18 mM and 400 mM) and solution temperature (25–80 °C) were used to obtain varied evaporation rates (0.1×10{sup −4}–5000×10{sup −4} ml/h). Different crystal sizes and shapes were obtained by changing solvents, mixture and initial solution volume. According to X-ray diffraction the samples are monocrystalline. The top surface was investigated by SEM. Optical band-gaps above 2 eV were obtained from photoacoustic spectroscopy. Photoluminescence spectra indicated band-to-band electronic transitions, and the presence of sub-band gap states. Excitons, structural defects and the presence of impurities are discussed and correlated to the electrical measurements. Crystals obtained using pure DMF as solvent showed better general properties, including under the exposure to mammographic X-ray energy range that led to sensibility of about 25 μC/Rcm{sup 2}.

  16. Crystal growth and applications of mercuric iodide. Report S-242-TP

    International Nuclear Information System (INIS)

    Schieber, M.; Roth, M.; Schnepple, W.F.

    1983-01-01

    A brief summary is given of a paper which discusses the crystal growth of mercuric iodide, a high-Z wide bandgap semiconductor suitable as a low noise, room temperature x-ray and gamma-ray detector. The paper summarized also reviews the state-of-the-art of the synthesis and purification of the starting material, mechanical properties and dislocation structure of HgI 2 , and recent success in the development of thick HgI 2 spectrometers

  17. Horizontal Ampoule Growth and Characterization of Mercuric Iodide at Controlled Gas Pressures for X-Ray and Gamma Ray Spectrometers

    International Nuclear Information System (INIS)

    Douglas, S.; McGregor Elsa; Ariesanti Bridget Corcoran

    2004-01-01

    The project developed a new method for producing high quality mercuric iodide crystals of x-ray and gamma spectrometers. Included are characterization of mercuric iodide crystal properties as a function of growth environment and fabrication and demonstration of room-temperature-operated high-resolution mercuric iodide spectrometers

  18. Mercuric iodide crystals obtained by solvent evaporation using ethanol

    International Nuclear Information System (INIS)

    Ugucioni, J.C.; Ghilardi Netto, T.; Mulato, M.

    2010-01-01

    Millimeter-sized mercuric iodide crystals were fabricated by the solvent evaporation technique using pure ethanol as a solvent. Three different conditions for solution evaporation were tested: (i) in the dark at room temperature; (ii) in the presence of light at room temperature and (iii) in an oven at 40 deg. C. Morphology, structure, optical and electrical properties were investigated using several techniques. Crystals fabricated in the dark show better properties and stability than others, possibly because the larger the energy of the system, the larger the number of induced growth defects. The crystals fabricated in the dark have adequate structure for higher resistivity and activation energy close to half the optical band-gap, as desired. With proper encapsulation these crystals might be good candidates for the development of ionizing radiation sensors.

  19. Mercuric iodide composite films using polyamide, polycarbonate and polystyrene fabricated by casting

    International Nuclear Information System (INIS)

    Ugucioni, J.C.; Ghilardi Netto, T.; Mulato, M.

    2010-01-01

    Mercuric iodide (HgI 2 ) composite films were obtained by using the casting technique. Insulator polymers such as polyamide, polycarbonate and polystyrene were mixed to HgI 2 crystallites forming a final sub-millimeter thick self-standing film. Fabrication temperature varied from 10 to 100 o C, and total fabrication time reached at most 5 min. The larger the fabrication temperature, the thinner the film and the smaller its electrical resistivity. Electrical characterization was performed in the dark, under UV illumination and under mammographic X-ray exposure. The final properties of the films are discussed and related to fabrication conditions. The optimized composite film might be a better candidate for use as X-ray detector for medical imaging, in place of the single HgI 2 crystalline device.

  20. A review of recent measurements of optical and thermal properties of α-mercuric iodide

    International Nuclear Information System (INIS)

    Burger, A.; Morgan, S.H.; Silberman, E.; Nason, D.; Cheng, A.Y.

    1991-01-01

    The knowledge of the physical properties of a crystal and their relation to the nature and content of defects are essential for both applications and fundamental reasons. Alpha-mercuric iodide (α-HgI 2 ) is a material which was found important applications as room temperature X-ray and gamma ray detectors. Some recent thermal and optical measurements of this material, using the samples of improved crystallinity which are now available, are reviewed below. Heretofore, these properties have received less attention than the mechanical and electrical properties, particularly at elevated temperatures. In the technology of α-HgI 2 where there is a continuing motivation to obtain larger single crystals without compromising the material quality, a better knowledge of the thermal and optical properties may lead to improvements in the processes of material purification, crystal growth and device fabrication

  1. Improved yield of high resolution mercuric iodide gamma-ray spectrometers

    International Nuclear Information System (INIS)

    Gerrish, V.; van den Berg, L.

    1990-01-01

    Mercuric iodide (HgI 2 ) exhibits properties which make it attractive for use as a solid state nuclear radiation detector. The wide bandgap (E g = 2.1 eV) and low dark current allow room temperature operation, while the high atomic number provides a large gamma-ray cross section. However, poor hole transport has been a major limitation in the routine fabrication of high-resolution spectrometers using this material. This paper presents the results of gamma-ray response and charge transport parameter measurements conducted during the past year at EG ampersand G/EM on 96 HgI 2 spectrometers. The gamma-ray response measurements reveal that detector quality is correlated with the starting material used in the crystal growth. In particular, an increased yield of high-resolution spectrometers was obtained from HgI 2 which was synthesized by precipitation from an aqueous solution, as opposed to using material from commercial vendors. Data are also presented which suggest that better spectrometer performance is tied to improved hole transport. Finally, some initial results on a study of detector uniformity reveal spatial variations which may explain why the correlation between hole transport parameters and spectrometer performance is sometimes violated. 6 refs., 3 figs

  2. Gabor zone-plate apertures for imaging with the mercuric iodide gamma-ray camera

    Energy Technology Data Exchange (ETDEWEB)

    Patt, B E [EG and G Energy Measurements, Inc., Goleta, CA (USA); Meyyappan, A; Cai, A; Wade, G [California Univ., Santa Barbara (USA). Dept. of Electrical and Computer Engineering

    1990-12-20

    Gabor zone-plate (GZP) apertures have been developed for use in EG and G EM's mercuric iodide (HgI{sub 2}) gamma-ray camera. The purpose of such an aperture is to increase efficiency, while maintaining good resolution. The GZP is similar to the Fresnel zone plate (FZP) but it has continuous transitions between opaque and transparent regions. Because there are no sharp transitions in the transmission, the inherent interference noise in GZP imaging is lower than that in FZP imaging. GZP parameters were chosen by considering the effects of constraints such as detector pixel size, number of pixels, minimum field of view required, maximum angle of incidence tolerated, and the Nyquist criterion for the minimum sampling rate. As a result an aperture was designed and fabricated with eight zones and a diameter of 3 cm. Lead was chosen as the aperture medium due to its high attenuation coefficient. Experimental data were obtained from the camera with the above GZP aperture. The point-spread function was determined and compared to the calculated response. Excellent agreement was obtained. The reconstruction process involves simulating, by computer, planar-wave illumination of a scaled transparency of the image and recording the intensity pattern at the focal plane. (orig.).

  3. High resolution diffraction imaging of mercuric iodide: Demonstration of the necessity for alternate crystal processing techniques for highly purified material

    International Nuclear Information System (INIS)

    Steiner, B.; Berg, L. van den; Laor, U.

    1995-01-01

    The overall crystalline lattice uniformity in recently available, highly purified mercuric iodide single crystals has been shown to be impacted by crystal handling techniques that were previously satisfactory. High resolution diffraction imaging of the surface regularity of crystals of various levels of purity and growth orientation shows: (1) that the newer materials have a generally lower level of precipitates, (2) that the incidence of these precipitates is now closely correlated with growth direction, and (3) that the deformation resistance and resulting sensitivity to crystal handling procedures are also closely correlated with these factors in this soft material. As a result, gentler cutting and polishing procedures have been developed and are shown to be effective in preserving overall lattice regularity in the new material. The polishing required to remove residual surface scratches affect the lattice orientation of the softer, precipitate-free regions, while not affecting those regions with detectable levels of precipitates. These results correlate closely with the electrical properties of devices made from these crystals. Mercuric iodide single crystals have proved to be particularly useful for x and γ ray detectors because their room temperature operation allow for simple, efficient, and compact instrumentation

  4. Vapor Growth of Mercuric Iodide Tetragonal Prismatic Crystals

    Science.gov (United States)

    2013-03-01

    placed inside a copper Faraday cage to minimize electronic noise. The measurement system consisted of an amplifier, an oscilloscope, a multi-channel...analyzer (MCA), a high voltage supply, a pulse generator, and a personal computer, all positioned outside the Faraday cage . Gamma- ray sources (241Am...measurement using a HgI2 Frisch collar detector. (a) The detector box and amplifier were placed inside a Faraday cage . (b) Details of the detec- tor

  5. Practical application of HgI2 detectors to a space-flight scanning electron microscope

    Science.gov (United States)

    Bradley, J. G.; Conley, J. M.; Albee, A. L.; Iwanczyk, J. S.; Dabrowski, A. J.

    1989-01-01

    Mercuric iodide X-ray detectors have been undergoing tests in a prototype scanning electron microscope system being developed for unmanned space flight. The detector program addresses the issues of geometric configuration in the SEM, compact packaging that includes separate thermoelectric coolers for the detector and FET, X-ray transparent hermetic encapsulation and electrical contacts, and a clean vacuum environment.

  6. Design and performance of a cesium iodide detector

    Energy Technology Data Exchange (ETDEWEB)

    Adams, T.; Bishop, J.M.; Cady, R. [Notre Dame Univ., IN (United States)] [and others

    1996-01-11

    The design, construction, and performance of a 198-element CsI detector built for Brookhaven experiment E852 is described. Design considerations for the array included such factors as rate, magnetic field, sensitivity and acceptance. Signals were obtained with a photodiode/preamplifier combination using PIN photodiodes. Data were taken over the course of two runs during the summers of 1993 and 1994. A calibration procedure using halo muons is described. The gain, energy resolution, and position resolution of the detector are discussed. Finally, the ability of the detector to be used as a low energy photon veto is illustrated using the data. (orig.).

  7. Calibration of sodium iodide crystal (NaI) gamma ray detector

    International Nuclear Information System (INIS)

    Azwah Jaafar; Juhari Yusof

    2005-01-01

    Sodium Iodide crystal gamma ray detector are widely used to detect leak in the pipeline linkage study, the complete mixing substances in of industrial processes, to measure the river and stream discharges and other usage in estuary and coastal sediment studies. These instruments are more sensitive as compared to other types of counters like Geiger Muller or plastic scintillation component. This calibration is to ensure the correct voltage for each detector. The characteristics of detector are different from each other. Once the operating voltage (HV) is determined it can be used effectively to measure the radiation in the application of nuclear techniques. (Author)

  8. Development and characterization of the lead iodide semiconductor detector

    International Nuclear Information System (INIS)

    Oliveira, Icimone Braga de

    2001-01-01

    A methodology for purification and growth of PbI 2 crystal as well as for its characterization as a room temperature radiation detector was developed in this work. Commercial salts were purified using the zone refining method and, for the purified material growth, the Bridgman method was used. To calculate the purification efficiency, studies of the decrease impurities concentrations were made in the salts and in three sections of the materials purified, using the neutron activation analysis technique. The results showed that the impurities segregate preferentially in the ingot final section. A significant decrease of the impurities concentration in function of the purification pass number was observed. The grown crystals presented good crystalline quality according to the results of the X-ray diffraction analysis. To evaluate the crystal as a semiconductor detector, measurements of dark leakage current, resistivity and the response of ( 241 Am) alpha particle and ( 241 Am, 57 Co, 133 Ba and 137 Cs) gamma rays were carried out. The radiation response is strongly dependent on the crystals purity. The crystals purified with 500 passes exhibited energy resolution of 10% for 241 Am alpha particle and the gamma rays resolution was compatible with the literature. The photosensibility of the PbI 2 crystal found in the wavelength from 400 to 600 nm range suggests an another application at this crystal as a photodetector to be coupled to scintillators. (author)

  9. Crystal growth and characterization of europium doped lithium strontium iodide scintillator as an ionizing radiation detector

    Science.gov (United States)

    Uba, Samuel

    High performance detectors used in the detection of ionizing radiation is critical to nuclear nonproliferation applications and other radiation detectors applications. In this research we grew and tested Europium doped Lithium Strontium Iodide compound. A mixture of lithium iodide, strontium iodide and europium iodide was used as the starting materials for this research. Congruent melting and freezing temperature of the synthesized compound was determined by differential scanning calorimetry (DSC) using a Setaram Labsys Evo DSC-DTA instrument. The melting temperatures were recorded at 390.35°C, 407.59°C and freezing temperature was recorded at 322.84°C from a graph of heat flow plotted against temperature. The synthesized material was used as the charge for the vertical Bridgeman growth, and a 6.5 cm and 7.7cm length boule were grown in a multi-zone transparent Mullen furnace. A scintillating detector of thickness 2.53mm was fabricated by mechanical lapping in mineral oil, and scintillating response and timing were obtained to a cesium source using CS-137 isotope. An energy resolution (FWHM over peak position) of 12.1% was observed for the 662keV full absorption peak. Optical absorption in the UV-Vis wavelength range was recorded for the grown crystal using a U-2900 UV/VIS Spectrophotometer. Absorption peaks were recorded at 194nm, 273nm, and 344nm from the absorbance spectrum, various optical parameters such as absorption coefficient, extinction coefficient, refractive index, and optical loss were derived. The optical band gap energy was calculated using Tauc relation expression at 1.79eV.

  10. Instrumental basis utilizing a sodium iodide detector for radioactive soil evaluations for site remediation

    International Nuclear Information System (INIS)

    Davis, A.I.

    1996-07-01

    This document provides the design rational for using a 5.08 by 5.08 cm (2 by 2 in.) sodium iodide detector to aid in boundary mapping of the radioactive contaminated soils at the Hanford Site. The detector can provide adequate response to a homogeneously contaminated soil volume of at least 1.22 to 1.52 m in diameter and up to 45.7 cm deep. The gamma activity basis is described by a soil column in a right circular cylinder that is uniformly isotopic. The detection techniques and characteristics are used to define contaminated areas requiring excavation by locating regions where gamma activities exceed cleanup standards. To determine the areas and boundary of contamination, the boundary and adjacent surfaces will be mapped using the detector operated in a windowed gross-gamma mode

  11. Purification of HGI2 for nuclear detector fabrication

    International Nuclear Information System (INIS)

    Schieber, M.M.

    1978-01-01

    A process for purification of mercuric iodide (HgI 2 ) to be used as a source material for the growth of detector quality crystals. The high purity HgI 2 raw material is produced by a combination of three stages: synthesis of HgI 2 from Hg and I 2 , repeated sublimation, and zone refining

  12. Mercuric chloride poisoning

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002474.htm Mercuric chloride poisoning To use the sharing features on this page, please enable JavaScript. Mercuric chloride is a very poisonous form of mercury. It ...

  13. Development of crystals based in cesium iodide for application as radiation detectors

    International Nuclear Information System (INIS)

    Pereira, Maria da Conceicao Costa

    2006-01-01

    Inorganic scintillators with fast luminescence decay time, high density and high light output have been the object of studies for application in nuclear physics, high energy physics, nuclear tomography and other fields of science and engineering. Scintillation crystals based on cesium iodide (CsI) are matters with relatively low higroscopy, high atomic number, easy handling and low cost, characteristics that favor their use as radiation detectors. In this work, the growth of pure CsI crystals, CsI:Br and CsI:Pb, using the Bridgman technique, is described. The concentration of the bromine doping element (Br) was studied in the range of 1,5x10 -1 M to 10 -2 M and the lead (Pb) in the range of 10 -2 M to 5x10 -4 M. To evaluate the scintillators developed, systematic measurements were carried out for luminescence emission and luminescence decay time for gamma radiation, optical transmittance assays, Vickers micro-hardness assays, determination of the doping elements distribution along the grown crystals and analysis of crystals response to the gamma radiation in the energy range of 350 keV to 1330 keV and alpha particles from a 241 Am source, with energy of 5.54 MeV. It was obtained 13 ns to 19 ns for luminescence decay time for CsI:Br and CsI:Pb crystals. These results were very promising. The results obtained for micro-hardness showed a significant increase in function of the doping elements concentration, when compared to the pure CsI crystal, increasing consequently the mechanical resistance of the grown crystals. The validity of using these crystals as radiation sensors may be seen from the results of their response to gamma radiation and alpha particles. (author)

  14. HgI2 detector fabrication

    International Nuclear Information System (INIS)

    Gonzalez, M.; Perez, J. M.

    1996-01-01

    The aim of the present work is to describe the steps followed to fabricate an ionizing radiation detector based on synthetic mercuric iodide monocrystal layers. Firstly, the crystalline orientation method has been describe, which is needed before the layer cutting perpendicularly to the (001) crystallographic. It is also defined the proceeding to crystal face finishing by a mechanical polishing and subsequent chemical etching. then, the metal electrode deposition and the view connection has been explained. Finally, the technique followed to encapsulate the detector with a polymeric thin film deposition has been described. (Author) 10 refs

  15. HgI2 detector fabrication

    International Nuclear Information System (INIS)

    Gonzalez, M.; Perez, J.M.

    1996-01-01

    The aim of the present work is to describe the steps followed to fabricate an ionizing radiation detector based on synthetic mercuric iodide monocrystal layers. Firstly, the crystalline orientation method has been describe, which is needed before the layer cutting perpendicullarly to the (001) crystallographyc. It is also defined the proceeding to crystal face finishing by a mechanical polishing and subsequent chemical etching. Then, the metal electrode deposition and the wire connection has been explained. Finally, the technique followed to encapsulate the detector with a polimeric thin film deposition has been described

  16. High Momentum Particle Identification Detector The Study of Cesium Iodide Quantum Efficiency Dependency on Substrate Material, Temperature and Quartz Window

    CERN Document Server

    Wisna, Gde Bimananda M

    2014-01-01

    The Cesium Iodide (CsI) is used as a material for detecting Cherenkov radiation produced by high momentum particle in High Momentum Particle Identification Detector (HMPID) at ALICE Experiment at CERN. This work provides investigation and analysis of The Quantum Efficiency (QE) result of CsI which is deposited on five samples substrates such as copper passivated red, copper passivated yellow, aluminium, copper coated with nickel and copper coated with nickel then coated with gold. The measurement of five samples is held under temperature $60^{0}$ C and $25^{0}$ C (room temperature) and also with optical quartz window which can be adjusted to limit the wavelength range which reach the CsI. The result shows there are dependency of substrate, temperature due to enhancement effect and also quartz windows usage on QE of CsI. The results of five samples is then compared and analyzed.

  17. Iodide- and bromide-specific electron-capture/photodetachment-modulated detector for the trace analysis of halocarbon mixtures

    International Nuclear Information System (INIS)

    Mock, R.S.; Grimsrud, E.P.

    1988-01-01

    The use of photodetachment (PD) of electrons from negative ions in a pulsed electron capture detector (ECD) is described. By passing a chopped light beam through the ECD and amplification of the modulated component of the ECD signal, the photodetachment-modulated (PDM) pulsed ECD can be made to respond selectively and sensitively to iodine- containing hydrocarbons alone, or to iodine- and bromine-containing hydrocarbons in the presence of chlorinated hydrocarbons. The detection limit of the iodide/bromide-specific mode of the PDM-ECD to CH 3 I is shown to be competitive with that of the normal mode of the pulsed ECD. This detection mode of the ECD is shown to be of great assistance in the gas chromatographic analysis of organobromides and organoiodides in complex mixtures which contain a large number of organochlorides

  18. HgI{sub 2} detector fabrication; Construccion de detectores de HgI{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, M.; Perez, J. M.

    1996-07-01

    The aim of the present work is to describe the steps followed to fabricate an ionizing radiation detector based on synthetic mercuric iodide monocrystal layers. Firstly, the crystalline orientation method has been describe, which is needed before the layer cutting perpendicularly to the (001) crystallographic. It is also defined the proceeding to crystal face finishing by a mechanical polishing and subsequent chemical etching. then, the metal electrode deposition and the view connection has been explained. Finally, the technique followed to encapsulate the detector with a polymeric thin film deposition has been described. (Author) 10 refs.

  19. Design and theoretical investigation of a digital x-ray detector with large area and high spatial resolution

    Science.gov (United States)

    Gui, Jianbao; Guo, Jinchuan; Yang, Qinlao; Liu, Xin; Niu, Hanben

    2007-05-01

    X-ray phase contrast imaging is a promising new technology today, but the requirements of a digital detector with large area, high spatial resolution and high sensitivity bring forward a large challenge to researchers. This paper is related to the design and theoretical investigation of an x-ray direct conversion digital detector based on mercuric iodide photoconductive layer with the latent charge image readout by photoinduced discharge (PID). Mercuric iodide has been verified having a good imaging performance (high sensitivity, low dark current, low voltage operation and good lag characteristics) compared with the other competitive materials (α-Se,PbI II,CdTe,CdZnTe) and can be easily deposited on large substrates in the manner of polycrystalline. By use of line scanning laser beam and parallel multi-electrode readout make the system have high spatial resolution and fast readout speed suitable for instant general radiography and even rapid sequence radiography.

  20. Flexible X-ray detector based on sliced lead iodide crystal

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Hui; Gao, Xiuying [College of Optoelectronic Technology, Chengdu University of Information Technology, Chengdu (China); Department of Materials Science, Sichuan University, Chengdu (China); Zhao, Beijun [Department of Materials Science, Sichuan University, Chengdu (China); Yang, Dingyu; Wangyang, Peihua; Zhu, Xinghua [College of Optoelectronic Technology, Chengdu University of Information Technology, Chengdu (China)

    2017-02-15

    A promising flexible X-ray detector based on inorganic semiconductor PbI{sub 2} crystal is reported. The sliced crystals mechanically cleaved from an as-grown PbI{sub 2} crystal act as the absorber directly converting the impinging X-ray photons to electron hole pairs. Due to the ductile feature of the PbI{sub 2} crystal, the detector can be operated under a highly curved state with the strain on the top surface up to 1.03% and still maintaining effective detection performance. The stable photocurrent and fast response were obtained with the detector repeated bending to a strain of 1.03% for 100 cycles. This work presents an approach for developing efficient and cost-effective PbI{sub 2}-based flexible X-ray detector. Photocurrent responses of the flexible PbI{sub 2} X-ray detector with the strain on the top surface up to 1.03% proposed in this work with the cross sectional structure and curved detector photograph as insets. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Development of the mercury iodide semiconductor crystal for application as a radiation detector

    International Nuclear Information System (INIS)

    Martins, Joao Francisco Trencher

    2011-01-01

    In this work, the establishment of a technique for HgI growth and preparation of crystals, for use as room temperature radiation semiconductor detectors is described. Three methods of crystal growth were studied while developing this work: physical vapor transport (PVT); saturated solution of HgI 2 , using two different solvents; (a) dimethyl sulfoxide (DMSO) and (b) acetone, and the Bridgman method. In order to evaluate the obtained crystals by the three methods, systematic measurements were carried out for determining the stoichiometry, structure, orientation, surface morphology and impurity of the crystal. The influence of these physical chemical properties on the crystals development was studied, evaluating their performance as radiation detectors. The X-ray diffractograms indicated that the crystals were, preferentially, oriented in the (001) e (101) directions with tetragonal structure for all crystals. Nevertheless, morphology with a smaller deformation level was observed for the crystal obtained by the PVT technique, comparing to other methods. Uniformity on the surface layer of the PVT crystal was detected, while clear incrustations of elements distinct from the crystal could be viewed on the DMSO crystal surface. The best results as to radiation response were found for the crystal grown by physical vapor transport. Significant improvement in the HgI z2 radiation detector performance was achieved for purer crystals, growing the crystal twice by PVT technique. (author)

  2. Development and characterization of the lead iodide semiconductor detector; Desenvolvimento e caracterizacao do detector semicondutor de iodeto de chumbo

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Icimone Braga de

    2001-07-01

    A methodology for purification and growth of PbI{sub 2} crystal as well as for its characterization as a room temperature radiation detector was developed in this work. Commercial salts were purified using the zone refining method and, for the purified material growth, the Bridgman method was used. To calculate the purification efficiency, studies of the decrease impurities concentrations were made in the salts and in three sections of the materials purified, using the neutron activation analysis technique. The results showed that the impurities segregate preferentially in the ingot final section. A significant decrease of the impurities concentration in function of the purification pass number was observed. The grown crystals presented good crystalline quality according to the results of the X-ray diffraction analysis. To evaluate the crystal as a semiconductor detector, measurements of dark leakage current, resistivity and the response of ({sup 241}Am) alpha particle and ({sup 241}Am, {sup 57}Co, {sup 133}Ba and {sup 137}Cs) gamma rays were carried out. The radiation response is strongly dependent on the crystals purity. The crystals purified with 500 passes exhibited energy resolution of 10% for {sup 241} Am alpha particle and the gamma rays resolution was compatible with the literature. The photosensibility of the PbI{sub 2} crystal found in the wavelength from 400 to 600 nm range suggests an another application at this crystal as a photodetector to be coupled to scintillators. (author)

  3. Determination of major sodium iodide symporter (NIS) inhibitors in drinking waters using ion chromatography with conductivity detector.

    Science.gov (United States)

    Cengiz, Mehmet Fatih; Bilgin, Ayse Kevser

    2016-02-20

    Goiter is an important health problem all over the world and iodine deficiency is its most common cause. Perchlorate, thiocyanate and nitrate (called as major NIS inhibitors) are known to competitively inhibit iodide uptake by the thyroid gland and thus, human exposure to major NIS inhibitors is a public health concern. In this study, an ion chromatographic method for the determination of most common NIS inhibitor ions in drinking waters was developed and validated. This is the first study where an analytical method is used for the determination of major NIS inhibitors in drinking water by an ion chromatography system in a single run. Chromatographic separations were achieved with an anion-exchange column and separated ions were identified by a conductivity detector. The method was found to be selective, linear, precise accurate and true for all of interested ions. The limits of the detections (LOD) were estimated at 0.003, 0.004 and 0.025mgL(-1) for perchlorate, thiocyanate and nitrate, respectively. Possible interference ions in drinking waters were examined for the best separation of NIS inhibitors. The excellent method validation data and proficiency test result (Z-score for nitrate: -0.1) of the FAPAS(®) suggested that the developed method could be applied for determination of NIS inhibitor residues in drinking waters. To evaluate the usefulness of the method, 75 drinking water samples from Antalya/Turkey were analyzed for NIS inhibitors. Perchlorate concentrations in the samples ranged from not detected (less than LOD) to 0.07±0.02mgL(-1) and the range of nitrate concentrations were found to be 3.60±0.01mgL(-1) and 47.42±0.40mgL(-1). No thiocyanate residues were detected in tested drinking water samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Fabrication of radiation detectors with HgI2 crystals grown from a solution

    International Nuclear Information System (INIS)

    Friant, Alain; Mellet, Jean; Saliou, Charles; Mohammed Brahim, Tayeb.

    1979-01-01

    Mercuric Iodide crystals grown from a solution of molecular complexes with dimethylsulfoxide have been evaluated as γ-ray and X-ray room temperature detectors. Compared with materials grown from the vapor phase these crystals are characterized by a larger size, a lower level of native defects, but a higher impurity level. Detector technology, X-ray and γ-ray (up to 662 keV) detection properties and characterization measurements (T.S.C., photoconductivity, photovoltaic effect) are described. The effect of light on crystal properties is briefly discussed [fr

  5. Development of crystals based in cesium iodide for application as radiation detectors; Desenvolvimento de cristais baseados em iodeto de cesio para aplicacao como detectores de radiacao

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Maria da Conceicao Costa

    2006-07-01

    Inorganic scintillators with fast luminescence decay time, high density and high light output have been the object of studies for application in nuclear physics, high energy physics, nuclear tomography and other fields of science and engineering. Scintillation crystals based on cesium iodide (CsI) are matters with relatively low higroscopy, high atomic number, easy handling and low cost, characteristics that favor their use as radiation detectors. In this work, the growth of pure CsI crystals, CsI:Br and CsI:Pb, using the Bridgman technique, is described. The concentration of the bromine doping element (Br) was studied in the range of 1,5x10{sup -1} M to 10{sup -2} M and the lead (Pb) in the range of 10{sup -2} M to 5x10{sup -4} M. To evaluate the scintillators developed, systematic measurements were carried out for luminescence emission and luminescence decay time for gamma radiation, optical transmittance assays, Vickers micro-hardness assays, determination of the doping elements distribution along the grown crystals and analysis of crystals response to the gamma radiation in the energy range of 350 keV to 1330 keV and alpha particles from a {sup 241}Am source, with energy of 5.54 MeV. It was obtained 13 ns to 19 ns for luminescence decay time for CsI:Br and CsI:Pb crystals. These results were very promising. The results obtained for micro-hardness showed a significant increase in function of the doping elements concentration, when compared to the pure CsI crystal, increasing consequently the mechanical resistance of the grown crystals. The validity of using these crystals as radiation sensors may be seen from the results of their response to gamma radiation and alpha particles. (author)

  6. Potassium Iodide

    Science.gov (United States)

    ... certain other liquids including low-fat white or chocolate milk, flat soda, orange juice, raspberry syrup, or ... Potassium iodide may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away: swollen glands metallic taste in the ...

  7. Comparison of sodium iodide and solid-state detectors for the measurement of lung-stored uranium

    International Nuclear Information System (INIS)

    King, A.; Scott, L.M.; Disney, J.L.

    1978-01-01

    A series of measurement of uranium sources were made, using a solid state detector consisting of 4 high-purity germanium detectors, and compared with measurements made with a single NaI detector. The comparative efficiencies at various energies are shown. As energy increases the differences in efficiencies increase in favour of NaI. A estimate of detection sensitivity gave the limit of error on the net count of a subject with one maximum permissible lung burden as 27 +- 7.2 counts/min for NaI and 3.73 +- 1.04 counts/min for the solid state detector. On a microgram basis the respective limits of error are +- 66 and +- 67 μg. It is concluded that solid state detectors can give 17 times better resolution compared with NaI while maintaining the same detection sensitivity. Sensitivity is related to the scatter of higher energy gammas into a fairly wide energy range. This 17-fold improvement in resolution results in a narrower energy range in which the scattered radiation can fall. Thus gamma analysis with such a system would be less subject to background errors. (author)

  8. Quantum efficiency of cesium iodide photocathodes in the 120-220 nm spectral range traceable to a primary detector standard

    CERN Document Server

    Rabus, H; Richter, M; Ulm, G; Friese, J; Gernhäuser, R; Kastenmüller, A; Maier-Komor, P; Zeitelhack, K

    1999-01-01

    Differently prepared CsI samples have been investigated in the 120-220 nm spectral range for their quantum efficiency, spatial uniformity and the effect of radiation aging. The experiments were performed at the PTB radiometry laboratory at the Berlin synchrotron radiation facility BESSY. A calibrated GaAsP Schottky photodiode was used as transfer detector standard to establish traceability to the primary detector standard, because this type of photodiode - unlike silicon p-on-n photodiodes - proved to be of sufficiently stable response when exposed to vacuum ultraviolet radiation. The paper reviews the experimental procedures that were employed to characterize and calibrate the GaAsP photodiode and reports the results that were obtained on the investigated CsI photocathodes.

  9. Radiation damage measurements in room temperature semiconductor radiation detectors

    International Nuclear Information System (INIS)

    Franks, L.A.; Olsen, R.W.; James, R.B.; Brunett, B.A.; Walsh, D.S.; Doyle, B.L.; Vizkelethy, G.; Trombka, J.I.

    1998-01-01

    The literature of radiation damage measurements on cadmium zinc telluride (CZT), cadmium telluride (CT), and mercuric iodide (HgI 2 ) is reviewed and in the case of CZT supplemented by new alpha particle data. CZT strip detectors exposed to intermediate energy (1.3 MeV) proton fluences exhibit increased interstrip leakage after 10 10 p/cm 2 and significant bulk leakage after 10 12 p/cm 2 . CZT exposed to 200 MeV protons shows a two-fold loss in energy resolution after a fluence of 5 x 10 9 p/cm 2 in thick (3 mm) planar devices but little effect in 2 mm devices. No energy resolution effects were noted from moderated fission spectrum of neutrons after fluences up to 10 10 n/cm 2 , although activation was evident. Exposures of CZT to 5 MeV alpha particle at fluences up to 1.5 x 10 10 α/cm 2 produced a near linear decrease in peak position with fluence and increases in FWHM beginning at about 7.5 x 10 9 α/cm 2 . CT detectors show resolution losses after fluences of 3 x 10 9 p/cm 2 at 33 MeV for chlorine-doped detectors. Indium doped material may be more resistant. Neutron exposures (8 MeV) caused resolution losses after fluences of 2 x 10 10 n/cm 2 . Mercuric iodide has been studied with intermediate energy protons (10 to 33 MeV) at fluences up to 10 12 p/cm 2 and with 1.5 GeV protons at fluences up to 1.2 x 10 8 p/cm 2 . Neutron exposures at 8 MeV have been reported at fluences up to 10 15 n/cm 2 . No radiation damage was reported under these irradiation conditions

  10. Field-portable high-resolution EDXRF analysis with HgI2-detector-based instrumentation

    International Nuclear Information System (INIS)

    Berry, P.F.; Little, S.R.; Voots, G.R.

    1992-01-01

    Energy dispersive x-ray fluorescence (EDXRF) analysis is well known for its efficient use of x-ray detector technology for simultaneous multielement determination. Low-intensity excitation, such as from a radioisotope source, can thus be employed and has enabled the design of many types of truly portable EDXRF instrumentation. Portable design, however, has not been without significant compromise in analytical performance because of the limited x-ray resolving power of prior detection methods, except by the use of a cryogenically operated detector. The developments we refer to stem from the use of a comparatively new x-ray detection device fabricated from mercuric iodide (HgI 2 ). For this detector, only a modest degree of cooling is required to achieve an energy resolution of > 300 eV. Two field-portable instrument designs of different hand-held measurement probe configurations are available that have applications for industrial quality assurance and environmental screening

  11. Use of HgI2 as gamma radiation detector

    International Nuclear Information System (INIS)

    Perez Morales, J.M.

    1993-01-01

    The Mercuric Iodide (HgI 2 ) has become one of the most promising room temperature semiconductors for the construction of X and gamma radiation detectors. The classical methods of spectroscopy have not demonstrated to achieve optimum results with HgI 2 detectors, mainly due to its particular carrier transport properties. Several alternative spectroscopic methods developed in the last ten years are presented and commented, selecting for a complete study one of them: 'The Partial Charge Collection Method'. The transport properties of the carriers generated by the radiation in the detector is specially important for understanding the spectroscopic behaviour of the HgI 2 detectors. For a rigorous characterization of this transport, it has been studied a digital technique for the analysis of the electric pulses produced by the radiation. Theoretically, it has been developed a Monte Carlo simulation of the radiation detection and the electronic signal treatment processes with these detectors in the energy range of 60-1300 KeV. These codes are applied to the study of the The Partial Charge Collection Method and its comparison with gaussian methods. Experimentally, this digital techniques is used for the study of the transport properties of thin HgI 2 detectors. Special interest is given to the contribution of the slower carriers, the holes, obtaining some consequent of spectroscopic interest. Finally, it is presented the results obtained with the first detectors grown and mounted in CIEMAT with own technology. (author). 129 ref

  12. Auger recombination in sodium iodide

    Science.gov (United States)

    McAllister, Andrew; Kioupakis, Emmanouil; Åberg, Daniel; Schleife, André

    2014-03-01

    Scintillators are an important tool used to detect high energy radiation - both in the interest of national security and in medicine. However, scintillator detectors currently suffer from lower energy resolutions than expected from basic counting statistics. This has been attributed to non-proportional light yield compared to incoming radiation, but the specific mechanism for this non-proportionality has not been identified. Auger recombination is a non-radiative process that could be contributing to the non-proportionality of scintillating materials. Auger recombination comes in two types - direct and phonon-assisted. We have used first-principles calculations to study Auger recombination in sodium iodide, a well characterized scintillating material. Our findings indicate that phonon-assisted Auger recombination is stronger in sodium iodide than direct Auger recombination. Computational resources provided by LLNL and NERSC. Funding provided by NA-22.

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

    Science.gov (United States)

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

    2013-11-12

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

  14. Development of a portable X-ray and gamma-ray detector instrument and imaging camera for use in radioactive and hazardous materials management

    International Nuclear Information System (INIS)

    Scyoc, J.M. van; James, R.B.; Anderson, R.J.

    1997-08-01

    The overall goal of this LDRD project was to develop instruments for use in the management of radioactive and hazardous wastes. Devices for identifying and imaging such wastes are critical to developing environmental remediation strategies. Field portable units are required to enable the on-site analysis of solids, liquids, and gas effluents. Red mercuric iodide (α-HgI 2 ) is a semiconductor material that can be operated as a high-energy-resolution radiation detector at ambient temperatures. This property provides the needed performance of conventional germanium- and silicon-based devices, while eliminating the need for the cryogenic cooling of such instruments. The first year of this project focused on improving the materials properties of the mercuric iodide to enable the new sensor technology; in particular the charge carrier traps limiting device performance were determined and eliminated. The second year involved the development of a field portable x-ray fluorescence analyzer for compositional analyses. The third and final year of the project focused on the development of imaging sensors to provide the capability for mapping the composition of waste masses. This project resulted in instruments useful not only for managing hazardous and radioactive wastes, but also in a variety of industrial and national security applications

  15. Studies on the mercuric chloride resistance of Staphylococcus aureus

    Energy Technology Data Exchange (ETDEWEB)

    Vaczi, L; Fodor, M; Milch, H; Rethy, A

    1962-01-01

    Among 409 pathogenic Staph. aureus strains 34% have been found to be sensitive, and 66% resistant, to mercuric chloride. The incidence of mercuric chloride resistant cultures among antibiotic sensitive staphylococci was 20%; among strains resistant to penicillin or to more than one antibiotic, 70%. Mercuric chloride resistant organisms occurred chiefly among phage group I and untypable strains; they were especially common among the so called epidemic strains of phage group I, and among cultures resistant to 4-6 antibiotics. In mercuric chloride sensitivity a thirtyfold, in merthiolate sensitivity only a two-fold difference has been revealed among the strains. The sulfydryl group content of mercuric chloride resistant organisms was only 1 1/2 times higher than that of sensitive bacteria. As to p-chlor mercuric benzoate binding capacity, a twofold difference was found between mercuric chloride sensitive and resistant staphylococci. The differences in the mercuric chloride resistance of various staphylococcal strains might be due to differences in the chemical structure of the cell surface. 9 references, 1 figure, 6 tables.

  16. Development of a stable and sensitive semiconductor detector by using a mixture of lead(II) iodide and lead monoxide for NDT radiation dose detection

    Science.gov (United States)

    Heo, Y. J.; Kim, K. T.; Han, M. J.; Moon, C. W.; Kim, J. E.; Park, J. K.; Park, S. K.

    2018-03-01

    Recently, high-energy radiation has been widely used in various industrial fields, including the medical industry, and increasing research efforts have been devoted to the development of radiation detectors to be used with high-energy radiation. In particular, nondestructive industrial applications use high-energy radiation for ships and multilayered objects for accurate inspection. Therefore, it is crucial to verify the accuracy of radiation dose measurements and evaluate the precision and reproducibility of the radiation output dose. Representative detectors currently used for detecting the dose in high-energy regions include Si diodes, diamond diodes, and ionization chambers. However, the process of preparing these detectors is complex in addition to the processes of conducting dosimetric measurements, analysis, and evaluation. Furthermore, the minimum size that can be prepared for a detector is limited. In the present study, the disadvantages of original detectors are compensated by the development of a detector made of a mixture of polycrystalline PbI2 and PbO powder, which are both excellent semiconducting materials suitable for detecting high-energy gamma rays and X-rays. The proposed detector shows characteristics of excellent reproducibility and stable signal detection in response to the changes in energy, and was analyzed for its applicability. Moreover, the detector was prepared through a simple process of particle-in-binder to gain control over the thickness and meet the specific value designated by the user. A mixture mass ratio with the highest reproducibility was determined through reproducibility testing with respect to changes in the photon energy. The proposed detector was evaluated for its detection response characteristics with respect to high-energy photon beam, in terms of dose-rate dependence, sensitivity, and linearity evaluation. In the reproducibility assessment, the detector made with 15 wt% PbO powder showed the best characteristics of 0

  17. dl-Alaninium iodide

    Directory of Open Access Journals (Sweden)

    Kevin Lamberts

    2012-06-01

    Full Text Available The crystal structure of dl-alanine hydroiodide (1-carboxyethanaminium iodide, C3H8NO2+·I−, is that of an organic salt consisting of N-protonated cations and iodide anions. The compound features homochiral helices of N—H...O hydrogen-bonded cations in the [010] direction; neighbouring chains are related by crystallographic inversion centers and hence show opposite chirality. The iodide counter-anions act as hydrogen-bond acceptors towards H atoms of the ammonium and carboxy groups, and cross-link the chains along [100]. Thus, an overall two-dimensional network is formed in the ab plane. No short contacts occur between iodide anions.

  18. Synthetic and structural investigations of mercurous and mercuric organophosphonates and phenylarsonates

    Energy Technology Data Exchange (ETDEWEB)

    Padalwar, Nitin Balkrushna; Vidyasagar, Kanamaluru

    2016-11-15

    The following twelve mercurous and mercuric organophosphomates, bis/diphosphonates and phenylarsonates have been isolated and structurally characterized by single crystal X-ray diffraction, {sup 13}C-and {sup 31}P NMR, infrared and Raman spectroscopic methods: Hg{sub 2}(HO{sub 3}PC{sub 6}H{sub 5}){sub 2}(1), Hg{sub 2}(HO{sub 3}P(C{sub 6}H{sub 4})PO{sub 3}H)(2), Hg{sub 2}(HO{sub 3}P(C{sub 6}H{sub 4}){sub 2}PO{sub 3}H)(3), Hg{sub 2}(HO{sub 3}P(CH{sub 2}){sub 4}PO{sub 3}H)(4), Hg{sub 2}(O{sub 3}PC{sub 6}H{sub 5})·H{sub 2}O(5), (Hg{sub 2}){sub 2}(O{sub 3}P(CH{sub 2}){sub 2}PO{sub 3})(6), (Hg{sub 2}){sub 2}(O{sub 3}P(CH{sub 2}){sub 3}PO{sub 3})(7), Hg(O{sub 3}PC{sub 6}H{sub 5})·H{sub 2}O(8), Hg(O{sub 3}PCH{sub 2}C{sub 6}H{sub 5})·H{sub 2}O(9), Hg(O{sub 3}AsC{sub 6}H{sub 5})·H{sub 2}O(10), Hg{sub 3}(O{sub 3}AsC{sub 6}H{sub 5}){sub 2}(HO{sub 3}AsC{sub 6}H{sub 5}){sub 2}(11) and (Hg{sub 2})Hg{sub 3}(O{sub 3}P(C{sub 6}H{sub 4})PO{sub 3}){sub 2}·2H{sub 2}O(12). Compounds 1–7 are the first examples of mercurous phosphonates and di/bisphosphonates. They contain Hg{sub 2}O{sub 6} units, which consist of Hg{sub 2}{sup 2+} cations with Hg-Hg bond of ~2.5 Å length. Phenylphosphonates 1 and 5 are layered compounds, whereas bis/diphosphonates 2, 3, 4, 6 and 7 have pillared-layered and three-dimensional structures. Compounds 8–11 are layered mercuric phosphonates and phenylarsonates. Compound 12 is a three-dimensional mixed-valent mercury phenylenebisphosphonate. - Graphical abstract: The first examples of mercurous organophosphonates and organodiphosphonates have layered, pillared-layered and three-dimensional structures.

  19. Gamma spectroscopy modelization intercomparison of the modelization results using two different codes (MCNP, and Pascalys-mercure)

    International Nuclear Information System (INIS)

    Luneville, L.; Chiron, M.; Toubon, H.; Dogny, S.; Huver, M.; Berger, L.

    2001-01-01

    The research performed in common these last 3 years by the French Atomic Commission CEA, COGEMA and Eurisys Mesures had for main subject the realization of a complete tool of modelization for the largest range of realistic cases, the Pascalys modelization software. The main purpose of the modelization was to calculate the global measurement efficiency, which delivers the most accurate relationship between the photons emitted by the nuclear source in volume, punctual or deposited form and the germanium hyper pure detector, which detects and analyzes the received photons. It has been stated since long time that experimental global measurement efficiency becomes more and more difficult to address especially for complex scene as we can find in decommissioning and dismantling or in case of high activities for which the use of high activity reference sources become difficult to use for both health physics point of view and regulations. The choice of a calculation code is fundamental if accurate modelization is searched. MCNP represents the reference code but its use is long time calculation consuming and then not practicable in line on the field. Direct line-of-sight point kernel code as the French Atomic Commission 3-D analysis Mercure code can represent the practicable compromise between the most accurate MCNP reference code and the realistic performances needed in modelization. The comparison between the results of Pascalys-Mercure and MCNP code taking in account the last improvements of Mercure in the low energy range where the most important errors can occur, is presented in this paper, Mercure code being supported in line by the recent Pascalys 3-D modelization scene software. The incidence of the intrinsic efficiency of the Germanium detector is also approached for the total efficiency of measurement. (authors)

  20. Photochemical versus biological production of methyl iodide during Meteor 55

    Science.gov (United States)

    Richter, U.; Wallace, D.

    2003-04-01

    The flux of methyl iodide from sea to air represents the largest flux of iodine from the ocean to the atmosphere. Surface water concentrations and hence fluxes are particularly high in tropical regions. This flux may be responsible for the enrichment of iodine in the marine aerosol and may contribute to important processes in the marine boundary layer, including particle formation. Methyl iodide is commonly referred to as a biogenic gas, with both macroalgae and phytoplankton identified as important sources. On the other hand experimental and field data have shown the importance of photochemical production that is not necessarily associated directly with biological activity. During the Meteor cruise 55 along 11°N in the tropical Atlantic Ocean, a series of experiments were conducted to examine the biological vs. photochemical production of methyl iodide. A total of eight separate experiments were conducted. Production of CH3I in quartz glass flasks during 24 hour incubations (dark and natural sunlight) was measured under three experimental treatments: untreated seawater, filtered seawater (0.1 um pore size filter to exclude most phytoplankton and bacteria), and seawater that was poisoned with mercuric chloride. There were two clear findings from these experiments: (1) methyl iodide production was significantly higher in all the incubations that were exposed to the light than in the dark incubations; (2) there was no significant difference between CH3I production under the three experimental treatments. These results argue very strongly for the primary importance of photochemical production of CH3I as opposed to biogenic production at least for the tropical open ocean surface waters. Further experiments are required to investigate the reactants involved, their sources, the wavelength and depth dependence of production, etc. as well as (possibly related) sink processes.

  1. Use of thick HgI2 detectors as intelligent spectrometers

    International Nuclear Information System (INIS)

    Olmos, P.; Garcia-Belmonte, G.; Perez, J.M.; Diaz, J.C.

    1990-01-01

    Mercuric iodide is a very attractive material to detect ionizing radiation due to its high stopping power and wide energy gap, which allows the use of a small and compact detector at room temperature. However, the spectroscopic performances of these detectors are poor in comparisons with other more popular semiconductors with better transport characteristics. This effect becomes dramatic when thick crystals are used. The partial charge-collection method is reported to be the most suitable one for enhancing the energy resolution achieved with thick detectors. A Monte Carlo simulation of the behavior of the model and its dependence with crystals and electronic parameters is presented, giving operating rules that optimize the system performance in each situation. Specially designed hardware has been developed to extract the maximum information of the charge pulse produced by photon-detector interaction, according with the results of the simulation. As a final step, an automatic isotope-identification process, based on the use of neutral networks, is performed, the identification being the true output of the whole system. Due to the strong dependence of this output on the free hardware parameters, an adaptive network is designed to act on these parameters in such a way that the system converges automatically to the best identification. (orig.)

  2. Should 3K zoom function be used for detection of pneumothorax in cesium iodide/amorphous silicon flat-panel detector radiographs presented on 1K-matrix soft copies?

    International Nuclear Information System (INIS)

    Herrmann, Karin A.; Zech, C.J.; Reiser, M.F.; Bonel, H.M.; Staebler, A.; Voelk, M.; Strotzer, M.

    2006-01-01

    The purpose of the study was to evaluate observer performance in the detection of pneumothorax with cesium iodide and amorphous silicon flat-panel detector radiography (CsI/a-Si FDR) presented as 1K and 3K soft-copy images. Forty patients with and 40 patients without pneumothorax diagnosed on previous and subsequent digital storage phosphor radiography (SPR, gold standard) had follow-up chest radiographs with CsI/a-Si FDR. Four observers confirmed or excluded the diagnosis of pneumothorax according to a five-point scale first on the 1K soft-copy image and then with help of 3K zoom function (1K monitor). Receiver operating characteristic (ROC) analysis was performed for each modality (1K and 3K). The area under the curve (AUC) values for each observer were 0.7815, 0.7779, 0.7946 and 0.7066 with 1K-matrix soft copies and 0.8123, 0.7997, 0.8078 and 0.7522 with 3K zoom. Overall detection of pneumothorax was better with 3K zoom. Differences between the two display methods were not statistically significant in 3 of 4 observers (p-values between 0.13 and 0.44; observer 4: p=0.02). The detection of pneumothorax with 3K zoom is better than with 1K soft copy but not at a statistically significant level. Differences between both display methods may be subtle. Still, our results indicate that 3K zoom should be employed in clinical practice. (orig.)

  3. Radiation damage measurements in room-temperature semiconductor radiation detectors

    CERN Document Server

    Franks, L A; Olsen, R W; Walsh, D S; Vizkelethy, G; Trombka, J I; Doyle, B L; James, R B

    1999-01-01

    The literature of radiation damage measurements on cadmium zinc telluride (CZT), cadmium telluride (CT), and mercuric iodide (HgI sub 2) is reviewed and in the case of CZT supplemented by new alpha particle data. CZT strip detectors exposed to intermediate energy (1.3 MeV) proton fluences exhibit increased interstrip leakage after 10 sup 1 sup 0 p/cm sup 2 and significant bulk leakage after 10 sup 1 sup 2 p/cm sup 2. CZT exposed to 200 MeV protons shows a two-fold loss in energy resolution after a fluence of 5x10 sup 9 p/cm sup 2 in thick (3 mm) planar devices but little effect in 2 mm devices. No energy resolution effects were noted from a moderated fission spectrum of neutrons after fluences up to 10 sup 1 sup 0 n/cm sup 2 , although activation was evident. Exposures of CZT to 5 MeV alpha particles at fluences up to 1.5x10 sup 1 sup 0 alpha/cm sup 2 produced a near linear decrease in peak position with fluence and increases in FWHM beginning at about 7.5x10 sup 9 alpha/cm sup 2. CT detectors show resolution...

  4. Molecular Cloning and Expression of Bacterial Mercuric Reductase ...

    African Journals Online (AJOL)

    USER

    2010-06-21

    Jun 21, 2010 ... In order to characterize the bacterial mercuric reductase (merA) gene, mercury resistant (Hgr). Escherichia coli strains have been isolated from various mercury contaminated sites of India. Their minimum inhibitory concentration (MIC) for Hg and zone of inhibition for different antibiotics were measured, and ...

  5. Molecular Cloning and Expression of Bacterial Mercuric Reductase ...

    African Journals Online (AJOL)

    In order to characterize the bacterial mercuric reductase (merA) gene, mercury resistant (Hgr) Escherichia coli strains have been isolated from various mercury contaminated sites of India. Their minimum inhibitory concentration (MIC) for Hg and zone of inhibition for different antibiotics were measured, and finally mer operon ...

  6. Prenatal Mercuric Chloride Exposure Causes Developmental Deficits in Rat Cortex

    Directory of Open Access Journals (Sweden)

    Tayebeh Rastegar

    2011-09-01

    Full Text Available Introduction: Environmental pollution with heavy metals such as mercury is a major health problem. Growing studies on the field have shown the deleterious effects of mercury on human and nonhuman nervous system, especially in infants, however the effects of prenatal exposure to mercuricchloride on cortical development are not yet well understood. The aim of this study was to investigate the effect of prenatal exposure to mercuric chloride on morphological characteristics of brain cortex. Methods: Mercuric chloride (2 mg/kg or normal saline were injected (I.P. to 36 Sprague – dawley rats in the 8th, 9th or 10th day of gestation. The embryos were surgically removed in the 15th day of gestation, and brain cortices were studied by histological techniques. Results: Histological studies showed that embryos of mercuric chloride treated rats hadcortical neuronal disarrangement withdifferent orientations of nuclei, increased diameter of cortex, increased mitosis of cells, increased cell death, decreased cellular density and increased intracellular space. Conclusion: These findings suggest some micro structural abnormalities in cortical regions after prenatal exposure to mercuric chloride. These structural abnormalities may underliesome neurologic disturbances following mercury intoxication.

  7. Purification and preparation of bismuth(III) iodide for application as radiation semiconductor detector; Purificacao e preparacao do cristal semicondutor de iodeto de bismuto para aplicacao como detector de radiacao

    Energy Technology Data Exchange (ETDEWEB)

    Ferraz, Caue de Mello

    2016-11-01

    This study describes the experimental procedure of a BiI{sub 3} purification method powder, aiming a future application of these semiconductor crystals as room temperature radiation detector. The Repeated Vertical Bridgman Technique was applied for the purification, based on the melting and nucleation phenomena. An ampoule filled with a maximum of 25% by volume of BiI{sub 3} powder was mounted into the Bridgman furnace and vertically moved at a speed of 2 millimeters per hour, inside the furnace with programmed thermal gradient and temperature profile, at a temperature maximum of 530 deg C. The reduction of the impurities in the BiI{sub 3}, each purification, was analysed by Instrumental Neutron Activation Analysis (INAA), in order to evaluate the efficiency of the purification technique established in this work, for trace metal impurities. It was demonstrated that the Repeated Bridgman is effective to reduce the concentration of many impurities in BiI{sub 3}, such as Ag, As, Br, Cr, K, Mo, Na and Sb. The crystalline structure of the BiI{sub 3} crystal purified twice and third times was similar to the BiI{sub 3} pattern. However, for BiI{sub 3} powder and purified once an intensity contribution of the BiOI was observed in the diffractograms. It is known that semiconductor detectors fabricated from high purity crystal exhibit significant improvement in their performance compared to those produced from low purity crystals. (author)

  8. Feasibility Study for the Reduction of Perchlorate, Iodide, and Other Aqueous Anions

    National Research Council Canada - National Science Library

    Clewell, Rebecca A; Tsui, David T; Mattie, David R

    1999-01-01

    Cyclic Voltammetry (CV) was used as a technique to determine the feasibility of the use of a coulometric detector in the determination of perchlorate, iodide, and various other anions commonly found in drinking water...

  9. Potassium iodide stockpiling

    International Nuclear Information System (INIS)

    Krimm, R.W.

    1983-01-01

    After examination by the Federal Emergency Management Agency (FEMA) and other federal agencies of federal policy on the use and distribution of potassium iodide (KI) as a thyroid-blocking agent for use in off-site preparedness around commercial nuclear powerplants, FEMA believes the present shelf life of KI is too short, that the minimum ordering quantities are an obstacle to efficient procurement, and that the packaging format offered by the drug industry does not meet the wishes of state and local government officials. FEMA has asked assistance from the Food and Drug Administration in making it possible for those states wishing to satisfy appropriate requirements to do so at the minimum cost to the public. Given an appropriate packaging and drug form, there appears to be no reason for the federal government to have further involvement in the stockpiling of KI

  10. INNA for interelement correlations in rats after mercuric chloride exposure

    International Nuclear Information System (INIS)

    Tandon, L.; Ehmann, W.D.; Kasarskis, E.J.; Kentucky Univ., Lexington, KY

    1992-01-01

    In an animal model study, we exposed rats to mercuric chloride through drinking water continuously for eight to ten months. A group of these rats were then taken off mercuric chloride water and fed distilled water. A control group of rats was given distilled water. Rat brain, spinal cord, and kidney were analyzed to determine Hg and nine other elements by INAA. Significant imbalances were detected among the groups. Most of the mercury (Hg) was found to be eliminated from the tissues studied within the first thirty days. Implications of the data are discussed in light of observed trace element imbalances in amyotrophic lateral sclerosis and Alzheimer's disease. (author) 25 refs.; 1 fig.; 3 tabs

  11. Correlations between plastic deformation parameters and radiation detector quality in HgI2

    International Nuclear Information System (INIS)

    Georgeson, G.; Milstein, F.; California Univ., Santa Barbara

    1989-01-01

    Mercuric iodide radiation detectors of various grades of quality were subjected to shearing forces in the (001) crystallographic planes using a specially designed micromechanical shear testing fixture. Experimental measurements were made of (001) shear stress versus shear strain. Each of the stress-strain curves was described by two empirically determined deformation parameters, s 0 and σ, where s 0 is a measure of 'bulk yielding' and σ indicates the 'sharpness of yielding' during plastic deformation. It was observed that the deformation parameters of many HgI 2 single crystal samples fit the relation s 0 =8σ 2/3 and that significant deviation from this relation, with s 0 >8σ 2/3 , indicates poor detector quality. Work hardening by prior plastic deformation was also found to cause s 0 to depart (in an increasing manner) from the 8σ 2/3 relation. For good quality material that has not previously been plastically deformed, the deformation parameter s c =s 0 -2σ<19 psi; this parameter can be interpreted as the 'onset of plastic yielding'. The results are discussed in terms of dislocation mechanisms for plastic deformation, work hardening, and recovery of work hardening. (orig.)

  12. Iodide transport and breast cancer.

    Science.gov (United States)

    Poole, Vikki L; McCabe, Christopher J

    2015-10-01

    Breast cancer is the second most common cancer worldwide and the leading cause of cancer death in women, with incidence rates that continue to rise. The heterogeneity of the disease makes breast cancer exceptionally difficult to treat, particularly for those patients with triple-negative disease. To address the therapeutic complexity of these tumours, new strategies for diagnosis and treatment are urgently required. The ability of lactating and malignant breast cells to uptake and transport iodide has led to the hypothesis that radioiodide therapy could be a potentially viable treatment for many breast cancer patients. Understanding how iodide is transported, and the factors regulating the expression and function of the proteins responsible for iodide transport, is critical for translating this hypothesis into reality. This review covers the three known iodide transporters - the sodium iodide symporter, pendrin and the sodium-coupled monocarboxylate transporter - and their role in iodide transport in breast cells, along with efforts to manipulate them to increase the potential for radioiodide therapy as a treatment for breast cancer. © 2015 Society for Endocrinology.

  13. Localization of gastrointestinal deposition of mercuric chloride studied in vivo

    International Nuclear Information System (INIS)

    Nielsen, J.B.; Andersen, H.L.; Soerensen, J.A.; Andersen, O.

    1992-01-01

    During the last 5 years, the site of gastrointestinal absorption of inorganic mercury has been attempted identified mainly by experiments using perfused intestinal segments in vitro or in situ. The present investigation will discuss the localization of the absorption site for mercuric chloride based on a completely undisturbed in vivo experimental model in mice. As the mice were allowed to eat their normal diet during the experimental period, the present results would independently add to existing knowledge on intestinal absorption sites for inorganic mercury. The mice were given 203 Hg labelled mercuric chloride orally, either through stomach tube or in the drinking water, and were killed after various time intervals. Mercury was localized and quantified in various segments of the gastrointestinal tract by gamma-counting. Time course analysis of the segmental deposition of mercury demonstrated that the deposition mainly takes place in the proximal jejunum and suggested that a larger part of the jejunum than previously reported is involved in absorption of mercury. Using this in vivo model, tetraethylthiuram disulfide was demonstrated to increase the intestinal deposition and absorption without changing the site of deposition. (au)

  14. Methylation of mercuric chloride by human intestinal bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Rowland, I R; Grasso, P; Davies, M J

    1975-01-01

    There is now evidence that ingested mercuric chloride (HgCl/sub 2/) may be methylated, in vivo, in the rat intestine and, in vitro, by human feces. However, one cannot infer from these experiments that the microbial flora of the intestine is responsible for the methylation reaction, since the gut contents contain several sources of metabolic activity other than bacteria. Data are presented on the ability of pure cultures of bacteria and yeasts, isolated from human feces, to convert HgCl/sub 2/ to methylmercury. Strains of Escherichia coli, streptococci, staphylococci, bacteriodes and bifidobacteria were inoculated into a medium containing 0.1 M potassium phosphate buffer, pH 7.0, Bacto-tryptone, yeast extract and D-glucose, each at 0.5% (w/v). Results indicate that most strains of staphylococci, streptococci, yeasts and E. coli isolated from human feces, could synthesize methylmercury compounds. In contrast, few strains of obligate anaerobes could do so. Up to 6 ng methylmercury/ml were formed in 44 h from 2 ..mu..g mercuric chloride.

  15. Growth and fabrication of large size sodium iodide crystal scintillator

    International Nuclear Information System (INIS)

    Sabharwal, S.C.; Karandikar, S.C.; Mirza, T.; Ghosh, B.; Deshpande, R.Y.

    1979-01-01

    The growth of 80 - 135 mm dia. Sodium iodide crystals activated with thallium is described in the present report. The growth is effected in a glazed porcelain crucible in a protective ambient of dry nitrogen. The technical details of the equipment developed have been fully described. The results of measurements on the rate of growth of crystal and the optimization of different growth parameters are reported. The dependence of various factors upon the performance characteristics of the scintillator detectors made using these crystals is also discussed. The energy resolution obtained for a typical detector of dimensions 76 mm dia x 76 mm ht. is 10 percent. (auth.)

  16. Mercure IV code application to the external dose computation from low and medium level wastes

    International Nuclear Information System (INIS)

    Tomassini, T.

    1985-01-01

    In the present work the external dose from low and medium level wastes is calculated using MERCURE IV code. The code utilizes MONTECARLO method for integrating multigroup line of sight attenuation Kernels

  17. Placental and Fetal Disposition of Mercuric Ions in Rats Exposed to Methylmercury: Role of Mrp2

    Science.gov (United States)

    Bridges, Christy C.; Joshee, Lucy; Zalups, Rudolfs K.

    2012-01-01

    Methylmercury is a prevalent environmental toxicant that can have deleterious effects on a developing fetus. Previous studies indicate that the multidrug resistance-associated protein 2 (Mrp2) is involved in renal and hepatic export of mercuric ions. Therefore, we hypothesize that Mrp2 is also involved in export of mercuric ions from placental trophoblasts and fetal tissues. To test this hypothesis, we assessed the disposition of mercuric ions in pregnant Wistar and TR– (Mrp2-deficient) rats exposed to a single dose of methylmercury. The amount of mercury in renal tissues (cortex and outer stripe of outer medulla), liver, blood, amniotic fluid, uterus, placentas and fetuses was significantly greater in TR– rats than in Wistar rats. Urinary and fecal elimination of mercury was greater in Wistar dams than in TR– dams. Thus, our findings suggest that Mrp2 may be involved in the export of mercuric ions from maternal and fetal organs following exposure to methylmercury. PMID:23059061

  18. Digital radiography: Present detectors and future developments

    International Nuclear Information System (INIS)

    Perez-Mendez, V.

    1990-08-01

    Present detectors for digital radiography are of two classes: real time detectors and storage (non real time) types. Present real time detectors consist of image intensifier tubes with an internal cesium iodide layer x-ray converter. Non real time detectors involve linear sweep arrays or storage detectors such as film. Future detectors discussed here can be of both types utilizing new technologies such as hydrogenated amorphous silicon photodiode arrays coupled to thin film transistor arrays. 17 refs., 10 figs

  19. Iodide uptake by negatively charged clay interlayers?

    Science.gov (United States)

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

    2015-09-01

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

  20. The evolution of hydrogen and iodine by the decomposition of ammonium iodide and hydrogen iodide

    International Nuclear Information System (INIS)

    Ishikawa, Hiroshi; Nakane, Masanori; Ishii, Eiichi; Uehara, Itsuki; Miyake, Yoshizo

    1977-01-01

    As a fundamental study on thermochemical production of hydrogen from water, the evolution of hydrogen and iodine from ammonium iodide and hydrogen iodide was investigated. Hydrogen was evolved by the reaction of nickel with ammonium iodide or with hydrogen iodide, and the resulting nickel(II) iodide was decomposed thermally at 600 -- 700 0 C to form nickel. First, the iodination of powdered nickel with ammonium iodide was studied by heating their powder mixture. The maximum yield of hydrogen was obtained at a temperature near 430 0 C. The iodination of powdered nickel with gaseous ammonium iodide or with dry hydrogen iodide gas was also investigated. In this case, coating of nickel particles with a layer of resulting nickel(II) iodide prevented further conversion of nickel and lowered the reaction rate. Such a retardation effect was appreciably lessened by use of carrier. When nickel was supported on such a carrier as ''isolite'', the nickel was converted into nickel(II) iodide easily. In a reaction temperature from 400 to 500 0 C, the rate of reaction between nickel and hydrogen iodide increased slightly with the elevation of the reaction temperature. In the case of ammonium iodide, the reaction rate was higher than that for hydrogen iodide and decreased apparently with the elevation of the reaction temperature, because ammonium iodide decomposed to ammonia and hydrogen iodide. Tests using a fixed bed reactor charged with 8 -- 10 mesh ''isolite''-nickel (30 wt%) were also carried out. The maximum yield of hydrogen was about 80% for ammonium iodide at 430 0 C of reaction temperature and 60% for hydrogen iodide at 500 0 C. (auth.)

  1. Iodide uptake by negatively charged clay interlayers?

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  2. Clinical evaluation of digital radiography based on a large-area cesium iodide-amorphous silicon flat-panel detector compared with screen-film radiography for skeletal system and abdomen

    International Nuclear Information System (INIS)

    Okamura, Terue; Tanaka, Saori; Koyama, Koichi; Norihumi, Nishida; Daikokuya, Hideo; Matsuoka, Toshiyuki; Yamada, Ryusaku; Kishimoto, Kenji; Hatagawa, Masakatsu; Kudoh, Hiroaki

    2002-01-01

    The aim of this clinical study was to compare the image quality of digital radiography using the new digital Bucky system based on a flat-panel detector with that of a conventional screen-film system for the skeletal structure and the abdomen. Fifty patients were examined using digital radiography with a flat-panel detector and screen-film systems, 25 for the skeletal structures and 25 for the abdomen. Six radiologists judged each paired image acquired under the same exposure parameters concerning three observation items for the bone and six items for the abdomen. Digital radiographic images for the bone were evaluated to be similar to screen-film images at the mean of 42.2%, to be superior at 50.2%, and to be inferior at 7.6%. Digital radiographic images for the abdomen were judged to be similar to screen-film images at the mean of 43.4%, superior at 52.4%, and inferior at 4.2%; thus, digital radiographic images were estimated to be either similar as or superior to screen-film images at over 92% for the bone and abdomen. On the statistical analysis, digital radiographic images were also judged to be preferred significantly in the most items for the bone and abdomen. In conclusion, the image quality of digital radiography with a flat-panel detector was superior to that of a screen-film system under the same exposure parameters, suggesting that dose reduction is possible with digital radiography. (orig.)

  3. Chloride, bromide and iodide scintillators with europium

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2016-09-27

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

  4. INAA for interelement correlations in rats after mercuric chloride exposure

    International Nuclear Information System (INIS)

    Tandon, L.; Kasarskis, E.J.; Ehmann, W.D.

    1991-01-01

    Motor neurons in rat spinal cord have been shown to have a selective affinity for Hg in a study by Moeller-Madsen and Dansher (1986). In a related animal model study the authors have exposed seventeen rats to mercuric chloride through drinking water continuously for eight months. A control group of rats was given regular water. Rat brain, spinal cord, and kidney were irradiated with thermal neutrons for determination of Hg and 16 other elements by INAA. As expected, Hg was increased in all tissues from treated rats. Cs was significantly elevated in spinal cord of Hg-dosed rats. Kidney had a significant decrease in As, Co, and K with a significant increase in Br and Se in Hg-dosed rats. These results in rats are contrasted with data (Khare, et al., 1990) from patients with amyotrophic lateral sclerosis (ALS) to determine if the elemental imbalances in this neurodegenerative disease are primary alterations, or merely secondary effects related to Hg levels

  5. Mechanisms involved in the transport of mercuric ions in target tissues

    Science.gov (United States)

    Bridges, Christy C.; Zalups, Rudolfs K.

    2016-01-01

    Mercury exists in the environment in various forms, all of which pose a risk to human health. Despite guidelines regulating the industrial release of mercury into the environment, humans continue to be exposed regularly to various forms of this metal via inhalation or ingestion. Following exposure, mercuric ions are taken up by and accumulate in numerous organs, including brain, intestine, kidney, liver, and placenta. In order to understand the toxicological effects of exposure to mercury, a thorough understanding of the mechanisms that facilitate entry of mercuric ions into target cells must first be obtained. A number of mechanisms for the transport of mercuric ions into target cells and organs have been proposed in recent years. However, the ability of these mechanisms to transport mercuric ions and the regulatory features of these carriers have not been characterized completely. The purpose of this review is to summarize the current findings related to the mechanisms that may be involved in the transport of inorganic and organic forms of mercury in target tissues and organs. This review will describe mechanisms known to be involved in the transport of mercury and will also propose additional mechanisms that may potentially be involved in the transport of mercuric ions into target cells. PMID:27422290

  6. 21 CFR 172.375 - Potassium iodide.

    Science.gov (United States)

    2010-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.375 Potassium iodide. The food additive potassium iodide may be...

  7. Interaction of simple indium iodides with silver- and aluminium iodides

    International Nuclear Information System (INIS)

    Denisov, Yu.N.; Halova, N.S.; Fedorov, P.I.

    1976-01-01

    Fusibility diagrams of the systems InI-AlI 3 , InI-AgI, InI 2 -AgI, and InI 2 -AlI 3 have been studied. In the system InI-AlI 3 a compound InAlI 4 has been detected having a melting point 194 deg C and two lamination regions. In the system InI-AgI two compounds In 2 AgI 3 and InAgI 2 are formed which melt incongruently at 272 deg and 220 deg C, respectively. The formation of the compounds has been confirmed by X-ray phase analysis. Specific electroconductivity of a number of alloys of the system InI-AlI 3 has been studied. The systems of eutectic type formed by diiodide of indium with iodides of silver and aluminium have been studied by thermal and X-ray analysis and by measuring electroconductivity

  8. Dynamic iodide trapping by tumor cells expressing the thyroidal sodium iodide symporter

    International Nuclear Information System (INIS)

    Dingli, David; Bergert, Elizabeth R.; Bajzer, Zeljko; O'Connor, Michael K.; Russell, Stephen J.; Morris, John C.

    2004-01-01

    The thyroidal sodium iodide symporter (NIS) in combination with various radioactive isotopes has shown promise as a therapeutic gene in various tumor models. Therapy depends on adequate retention of the isotope in the tumor. We hypothesized that in the absence of iodide organification, isotope trapping is a dynamic process either due to slow efflux or re-uptake of the isotope by cells expressing NIS. Iodide efflux is slower in ARH-77 and K-562 cells expressing NIS compared to a thyroid cell line. Isotope retention half times varied linearly with the number of cells expressing NIS. With sufficient NIS expression, iodide efflux is a zero-order process. Efflux kinetics in the presence or absence of perchlorate also supports the hypothesis that iodide re-uptake occurs and contributes to the retention of the isotope in tumor cells. Iodide organification was insignificant. In vivo studies in tumors composed of mixed cell populations confirmed these observations

  9. Kinetic Isotope Effects in the Reduction of Methyl Iodide

    DEFF Research Database (Denmark)

    Holm, Torkil

    1999-01-01

    a Grignard reagent to methyl iodide, and for reduction of methyl iodide with tributyltin hydride or with gaseous hydrogen iodide. Very small KIE's were found for electron transfer to methyl iodide from magnesium in ether or from sodium in ammonia. The reason may be that these reactions are transport...

  10. Scrubbing of iodine from gas streams with mercuric nitrate-conversion of mercuric iodate product to barium iodate for fixation in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, G.C.; Moore, J.G.; Morgan, M.T.

    1980-06-01

    A bench-scale model of a mercuric nitrate scrubber for removal of iodine from off-gas streams was constructed and operated in conjunction with a mercuric iodate-to-barium iodate conversion system to determine the feasibility of total recycle of all processing solutions. The two main aspects of the system examined were (1) the extent of contamination of the barium iodate product, and (2) the effect of cross-contamination of various process solutions on the efficiency of the process. The experimental evidence obtained indicates that, with appropriate control, all solutions can be recycled without significant contamination of the product that would be harmful to the host concrete or to the environment. Mercury contamination was found to be less than or equal to 0.5 wt % of the barium iodate product. The most significant effect on system efficiency was determined to be barium hydroxide contamination of the sodium hydroxide solution used to convert mercuric iodate to sodium iodate. A mole ratio of barium hydroxide to sodium hydroxide of about 1:225 caused a decrease in conversion efficiency of about 45%.

  11. Methyl Iodide Decomposition at BWR Conditions

    International Nuclear Information System (INIS)

    Pop, Mike; Bell, Merl

    2012-09-01

    Based on favourable results from short-term testing of methanol addition to an operating BWR plant, AREVA has performed numerous studies in support of necessary Engineering and Plant Safety Evaluations prior to extended injection of methanol. The current paper presents data from a study intended to provide further understanding of the decomposition of methyl iodide as it affects the assessment of methyl iodide formation with the application of methanol at BWR Plants. This paper describes the results of the decomposition testing under UV-C light at laboratory conditions and its effect on the subject methyl iodide production evaluation. The study as to the formation and decomposition of methyl iodide as it is effected by methanol addition is one phase of a larger AREVA effort to provide a generic plant Safety Evaluation prior to long-term methanol injection to an operating BWR. Other testing phases have investigated the compatibility of methanol with fuel construction materials, plant structural materials, plant consumable materials (i.e. elastomers and coatings), and ion exchange resins. Methyl iodide is known to be very unstable, typically preserved with copper metal or other stabilizing materials when produced and stored. It is even more unstable when exposed to light, heat, radiation, and water. Additionally, it is known that methyl iodide will decompose radiolytically, and that this effect may be simulated using ultra-violet radiation (UV-C) [2]. In the tests described in this paper, the use of a UV-C light source provides activation energy for the formation of methyl iodide. Thus is similar to the effect expected from Cherenkov radiation present in a reactor core after shutdown. Based on the testing described in this paper, it is concluded that injection of methanol at concentrations below 2.5 ppm in BWR applications to mitigate IGSCC of internals is inconsequential to the accident conditions postulated in the FSAR as they are related to methyl iodide formation

  12. Prevention of organic iodide formation in BWR's

    International Nuclear Information System (INIS)

    Karjunen, T.; Laitinen, T.; Piippo, J.; Sirkiae, P.

    1996-01-01

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

  13. Nouveaux supraconducteurs à haute température critique à base de mercure

    Science.gov (United States)

    Michel, C.; Hervieu, M.; Martin, C.; Maignan, A.; Pelloquin, D.; Goutenoire, F.; Huvé, M.; Raveau, B.

    1994-11-01

    Structural and superconducting properties of new cations substituted mercury based oxides are described. They are mainly characterized by [ Hg{1-x}MxOδ] infty monolayers, however a compound with doubled [ Hg{1-x}MxOδ] infty layer is described for the first time. Critical temperatures vary in a large range 0leqslant T_cleqslant 130 K, but they are lower than those of related to pure mercury oxides. The influence of annealings in various atmospheres upon T_c is discussed. Les caractéristiques structurales et supraconductrices de nouveaux oxydes à base de mercure, dans lesquels le mercure est partiellement remplacé par un autre cation, sont décrites. Dans la majorité des cas, ces oxydes sont caractérisés par une monocouche [ Hg{1-x}MxOδ] infty ; cependant, pour la première fois un composé contenant une double couche majoritaire en mercure est isolé. Les températures critiques varient dans un large domaine (0-130 K) mais restent inférieures à celles des oxydes parents ll tout mercure gg. L'influence des recuits sous des atmosphères diverses est discutée.

  14. Teneurs en Plomb, Cadmium, Mercure et Zinc relevées dans la ...

    African Journals Online (AJOL)

    arsenic (As) et du titane (Ti)[1]. D'autres éléments traces tel que le mercure (Hg), le ..... tels que la modification du cycle biogéochimique et de la biodisponibilité des métaux [23-34,13,5 ] l'apparition des teneurs maximales en métaux (Cd, Pb, Cu.

  15. The effect of mercuric chloride treatment as biocide for herbaria on the indoor air quality

    NARCIS (Netherlands)

    Havermans, J.B.G.A.; Dekker, R.; Sportel, R.

    2015-01-01

    One of the most previous conservation treatments for plant specimen in herbarium collections was mercuric chloride (HgCl2). However, due time HgCl2 may decompose and it may cause (metallic) mercury (Hg) emission. Hg vapour in indoor air should be avoided as mercury poisoning can already occur at

  16. Synthesis of inherently chiral calixarenes via direct mercuration of the partial cone conformation

    Czech Academy of Sciences Publication Activity Database

    Slavík, P.; Kohout, M.; Böhm, S.; Eigner, Václav; Lhoták, P.

    2016-01-01

    Roč. 52, č. 11 (2016), s. 2366-2369 ISSN 1359-7345 R&D Projects: GA ČR GA15-12653S Institutional support: RVO:68378271 Keywords : calix[4]arene * mercuration * brigding * X-ray crystallography * Jana2006 Subject RIV: CC - Organic Chemistry Impact factor: 6.319, year: 2016

  17. In Vitro Bioavailability Study of an Antiviral Compound Enisamium Iodide

    OpenAIRE

    Eleonore Haltner-Ukomadu; Svitlana Gureyeva; Oleksii Burmaka; Andriy Goy; Lutz Mueller; Grygorii Kostyuk; Victor Margitich

    2018-01-01

    An investigation into the biopharmaceutics classification and a study of the in vitro bioavailability (permeability and solubility) of the antiviral compound enisamium iodide (4-(benzylcarbamoyl)-1-methylpyridinium iodide) were carried out. The solubility of enisamium iodide was determined in four different buffers. Apparent intestinal permeability (Papp) of enisamium iodide was assessed using human colon carcinoma (Caco-2) cells at three concentrations. The solubility of enisamium iodide in ...

  18. Cesium iodide photon converter performance in a gaseous RICH detector

    CERN Document Server

    Gernhäuser, R; Homolka, J; Kastenmüller, A; Kienle, P; Körner, H J; Maier-Komor, P; Peter, M; Zeitelhack, K

    1999-01-01

    The performance of a 48x48 cm sup 2 multi-wire proportional chamber for VUV photon detection in a RICH setup is reported. The MWPC pad cathode was covered with a solid CsI photo converter layer of 230 mu g/cm sup 2 thickness deposited on a resin-stabilized graphite (RSG) coating. Cherenkov light radiated from cosmic muons was detected in the wavelength region 160 nm95% and a constant long-term stability of the photo cathode were observed.

  19. Method to remove methyl iodide131 gas

    International Nuclear Information System (INIS)

    Deitz, V.R.; Blachly, C.H.

    1977-01-01

    A two-stage impregnation process for charcoal is presented which is to be used for radioactive iodine or methyl iodide removal from the waste gas of a nuclear reactor. In the first stage, the coal is treated at pH 10 with an aqueous mixture of a salt of iodic acid (hypoiodite, iodate, or periodate) with iodine or iodide. In the second stage, impregnation with a tertiary amine occurs. The concentrations are chosen so that the charcoal will take up between 0.5 and 4% by weight of iodine. (UWI) [de

  20. Factors affecting the retention of methyl iodide by iodide-impregnated carbon

    International Nuclear Information System (INIS)

    Hyder, M.L.; Malstrom, R.A.

    1991-01-01

    This paper comprises two sets of studies of methyl iodide retention by iodide-impregnated carbon. In the first of these, the retention of the methyl iodide on the carbon surface and its subsequent evolution were observed directly by a technique of combustion and phosphorescence. In the second, the methyl iodide retention in a standard test was compared with surface area measurements and the concentration of unreacted iodine. A correlation among these parameters was identified and characterized. Carbon quality was varied through the selection of used material with differing service histories. Air from the Savannah River Site reactor buildings is vented through carbon beds for control of radioiodine before release to the atmosphere. The carbon used is North American Carbon Co. type GX-176 coconut shell carbon impregnated with 1% triethylenedimaine (TEDA) and 2% potassium iodide by weight. Replacement intervals for the carbon have been as long as thirty months. Analysis of samples withdrawn at much shorter times has shown that the TEDA is lost after a few months, and the performance of the carbon for methyl iodide retention is dependent on the iodide impregnant. Efficient methyl iodide retention is not a requirement for carbon in this service; however, methyl iodide retention as measured by the ASTM Test D3803 (method B) has been found to correlate well with other desirable properties of the carbon such as radiation stability. The studies undertaken here were intended to shed light on the changes taking place in this carbon during long-term service and to provide a basis for simpler measurements of carbon quality

  1. 15-(para-[123I]iodophenyl) pentadecanoic acid obtained using mercuration and subsequent [123I] radioiodination

    International Nuclear Information System (INIS)

    Dougan, H.; Vincent, J.S.; Lyster, D.M.

    1989-01-01

    The present work explores the basic reactions necessary for the preparation of [ 123 I] 15-(paraiodophenyl)-pentadecanoic acid (IPPA) from organo mercury compounds. It was found that the essential reactions occur readily and with good yield. The steps were as follows: phenyl pentadecanoic acid or its ethyl ester may be mercurated using Hg(TFA) 2 in TFA solvent, and the para-chloromercury compounds may be recovered. [ 123 I] radioiodination may be carried out in a variety of solvents in the presence of chloramine T. When radioiodination was conducted at room temperature the isomeric purity of the ester or fatty acid was found to be 99.9% para. The results indicate that poor solubility of certain mercurated pentadecanoic acid compounds will limit the development of a kit for [ 123 I]IPPA. (author) 16 refs.; 2 tabs

  2. Effect of mercuric ions on growth and respiration of two coagulase-positive Staphylococcus aureus strains

    Energy Technology Data Exchange (ETDEWEB)

    Tynecka, Z; Szymona, O

    1966-01-01

    Sensitivity toward HgCl/sub 2/ of two coagulase-positive Staphylococcus aureus strains has been studied. Strain 15 proved to be over 10 times more resistant to HgCl/sub 2/ in the growth test than strain 31. The former showed also higher rates of endogenous respiration and more actively oxidized glucose in presence of HgCl/sub 2/. Strain 31 grew better in absence of HgCl/sub 2/ but readily underwent inhibition both in the growth and glucose oxidation experiment. Strain 31 was, however, less sensitive to HgCl/sub 2/, as detected by methylene blue reduction in presence of malate and succinate as substrates. Cysteine largely reversed the inhibitory effect of mercuric ions. Experiments with radioactive Hg/sup 203/Cl/sub 2/ did not prove the sensitive strain 31 to bind more mercuric ions than strain 15. 12 references, 4 figures, 4 tables.

  3. Réduction globale des émissions de mercure dans les exploitations ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    28 avr. 2016 ... La Convention de Minamata sur le mercure constitue le fer de lance des efforts déployés à l'échelle mondiale pour réduire les émissions. Elle fournit des mécanismes de contrôle et de réduction des émissions visant tous les processus de production et de transformation ainsi que toutes les industries ...

  4. Estimation de l\\'apport en mercure à partir de la consommation de ...

    African Journals Online (AJOL)

    Sur la base des concentrations et de la consommation annuelle de poissons estimée à 16 kg/habitant en Côte d\\'Ivoire, l\\'apport moyen calculé est égal à 73 μg de mercure par semaine; soit 25% de la dose hebdomadaire tolérable provisoire (DHTP) fixée à 300 μg par le comité mixte FAO/OMS. Cependant, pour une ...

  5. Hematotoxicity and genotoxicity of mercuric chloride following subchronic exposure through drinking water in male rats.

    Science.gov (United States)

    Boujbiha, Mohamed Ali; Ben Salah, Ghada; Ben Feleh, Abdelraouf; Saoudi, Mongi; Kamoun, Hassen; Bousslema, Ali; Ommezzine, Asma; Said, Khaled; Fakhfakh, Faiza; El Feki, Abdelfattah

    2012-07-01

    Erythrocytes are a convenient model to understand the subsequent oxidative deterioration of biological macromolecules in metal toxicities. The present study examined the variation of hematoxic and genotoxic parameters following subchronic exposure of mercuric chloride via drinking water and their possible association with oxidative stress. Male rats were exposed to 50 ppm (HG1) and 100 ppm (HG2) of mercuric chloride daily for 90 days. A significant dose-dependent decrease was observed in red blood cell count, hemoglobin, hematocrit, and mean cell hemoglobin concentration in treated groups (HG1 and HG2) compared with controls. A significant dose-dependent increase was observed in lipid peroxidation; therefore, a significant variation was found in the antioxidant enzyme activities, such as superoxide dismutase, catalase, and glutathione peroxidase. Interestingly, mercuric chloride treatment showed a significant dose-dependent increase in frequency of total chromosomal aberration and in percentage of aberrant bone marrow metaphase of treated groups (p mercury treatment may be the major cause for chromosomal aberration as free radicals lead to DNA damage. These data will be useful in screening the antioxidant activities of natural products, which may be specific to the bone marrow tissue.

  6. Brain uptake of Se 75-selenomethionine after damage to blood-brain barrier by mercuric ions

    Energy Technology Data Exchange (ETDEWEB)

    Steinwall, O

    1969-01-01

    Previous experimental studies have indicated that perfusing the vessels of the brain with mercuric ions may not only cause damage to the blood-brain barrier in allowing the extravasation of acid dyes, but also have the ostensibly contrary effect of diminishing the uptake of radioactive tracers for important nutrients. These observations were based on the direct comparison of the two hemispheres of the same animal, one perfused with mercuric ions and the other serving as a control. The present paper reports the results of a corresponding investigation with Se75-L-selenomethionine. This methionine analogue seems to be transported and metabolized in much the same way as natural methionine and is conveniently assayed due to the labelling into a ..gamma..-emitting isotope. In addition, as in this study, a check as to whether or not the mercuric ions caused asymmetry of the blood flow was desired, and the similar ..gamma..-emitting I 131-iodoantipyrine was used for this purpose. The long half-life of Se75 made it easy to distinguish in the same specimens its activity from that of the blood flow indicator.

  7. Potassium iodide capsule treatment of feline sporotrichosis.

    Science.gov (United States)

    Reis, Erica G; Gremião, Isabella D F; Kitada, Amanda A B; Rocha, Raphael F D B; Castro, Verônica S P; Barros, Mônica B L; Menezes, Rodrigo C; Pereira, Sandro A; Schubach, Tânia M P

    2012-06-01

    Sporotrichosis is a mycosis caused by Sporothrix schenckii. The most affected animal is the cat; it has played an important role in the zoonotic transmission of this disease, especially in Rio de Janeiro, Brazil, since 1998. In order to evaluate the treatment of feline sporotrichosis with potassium iodide, an observational cohort was conducted in 48 cats with sporotrichosis at Instituto de Pesquisa Clínica Evandro Chagas, Fiocruz. All cats received potassium iodide capsules, 2.5 mg/kg to 20 mg/kg q24h. The cure rate was 47.9%, treatment failure was 37.5%, treatment abandonment was 10.4% and death was 4.2%. Clinical adverse effects were observed in 52.1% of the cases. Thirteen cats had a mild increase in hepatic transaminase levels during the treatment, six of them presented clinical signs suggestive of hepatotoxicity. Compared to previous studies with itraconazole and iodide in saturated solution, potassium iodide capsules are an alternative for feline sporotrichosis treatment.

  8. Potentiometric determination of iodides in urine

    International Nuclear Information System (INIS)

    Gikolaev, B.A.; Primakova, L.N.; Rakhman'ko, E.M.

    1996-01-01

    Variants of potentiometric method: determination using a calibrations plot, the Gran method, and the double addition method are considered. The method of double additions of the test solution to the reference one is suggested as the most favorable method of determining iodides in urine under clinical laboratory conditions. Refs. 5, tabs. 2

  9. Inclusion complexation of tetrabutylammonium iodide by cyclodextrins

    Indian Academy of Sciences (India)

    Biswajit Datta

    Host-guest inclusion complex of an ionic solid (tetrabutyl ammonium iodide) with α- and β- cyclodextrin has been ... tions.2 CDs are cyclic oligomer of α-D-glucose having numerous of ... of locating at the interface of two phases (liquid–liquid.

  10. 21 CFR 184.1265 - Cuprous iodide.

    Science.gov (United States)

    2010-04-01

    ... the following specific limitations: Category of food Maximum treatment level in food Functional use... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Cuprous iodide. 184.1265 Section 184.1265 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  11. Iodide-trapping defect of the thyroid

    International Nuclear Information System (INIS)

    Pannall, P.R.; Steyn, A.F.; Van Reenen, O.

    1978-01-01

    We describe a grossly hypothyroid 50-year-old woman, mentally retarded since birth. On the basis of her history of recurrent goitre, absence of 131 I neck uptake and a low saliva/plasma 131 I ratio, congenital hypothyroidism due to a defect of the iodide-trapping mechanism was diagnosed. Other family members studied did not have the defect

  12. Electrosorption of tetraalkylammonium ions on silver iodide

    NARCIS (Netherlands)

    Keizer, de A.

    1981-01-01

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

  13. Electronic and optical properties of lead iodide

    DEFF Research Database (Denmark)

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

    2002-01-01

    The electronic properties and the optical absorption of lead iodide (PbI2) have been investigated experimentally by means of optical absorption and spectroscopic ellipsometry, and theoretically by a full-potential linear muffin-tin-orbital method. PbI2 has been recognized as a very promising...

  14. Vapor pressure of selected organic iodides

    Czech Academy of Sciences Publication Activity Database

    Fulem, M.; Růžička, K.; Morávek, P.; Pangrác, Jiří; Hulicius, Eduard; Kozyrkin, B.; Shatunov, V.

    2010-01-01

    Roč. 55, č. 11 (2010), 4780-4784 ISSN 0021-9568 R&D Projects: GA ČR GA203/08/0217 Institutional research plan: CEZ:AV0Z10100521 Keywords : vapor pressure * static method * organic iodides Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.089, year : 2010

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

    DEFF Research Database (Denmark)

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

    2006-01-01

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

  16. Iodide adsorption on the surface of chemically pretreated clinoptilolite

    International Nuclear Information System (INIS)

    Chmielewska-Horvatova, E.; Lesny, J.

    1995-01-01

    The possibility to use the monoionic Ag +- form (eventually Hg +- and Hg 2+ -forms) of clinoptilolite of domestic origin for radioactive iodide elimination from waters has been studied. The capacity of the monoforms of clinoptilolite towards iodide exceeds many times that of the capacity of clinoptilolite in natural form. Due to the low solubility product of AgI, Hg 2 I 2 and HgI 2 iodides generate precipitates on the zeolite surface. Rtg analyses of the silver form of clinoptilolite after sorption of iodide demonstrate the formation of new crystals on the zeolite surface. The influence of interfering anions on the adsorption capacity of silver clinoptilolite towards iodide was investigated, too. Kinetic curves of iodide desorption from the surface of silver and mercury clinoptilolite were compared. Simultaneously, adsorption isotherms for the systems aqueous iodide solution/Ag-, Hg-clinoptilolite were determined. (author) 6 refs.; 7 figs.; 4 tabs

  17. Complex crystals formed in the aqueous solution of copper(I) iodide and sodium iodide

    International Nuclear Information System (INIS)

    Sugasaka, Kazuhiko; Fujii, Ayako

    1977-01-01

    Crystals of different crystal habits were separated from the copper(I) iodide and sodium iodide solution and the thermal changes of the composition of copper(I) iodide and sodium iodide complexes were studied by chemical analysis, thermal analysis and X-ray diffractometry. Granular and columnar crystals were determined to be copper(I) iodide and sodium iodide dihydrate by X-ray diffraction analysis, respectively. Needle crystal (A) which was separated from the solution at 25 0 C was assumed to be Na 2 CuI 3 .6H 2 O. (A) was stable in its appearance in the air, but the X-ray diffraction pattern of (A) changed. Needle crystal (B) which was recrystallized at 10 0 C from mother liquor after the separation of crystal (A) was assumed to be NaCuI 2 .4H 2 O. (B) was hygroscopic and decomposed to precipitate copper(I) iodide with moisture in the air. (A) and (B) were found to change by heating and or drying, respectively, as follows: Na 2 CuI 3 .6H 2 O → (-2H 2 O, 80 0 C) → 2NaI.2H 2 O + CuI → (-4H 2 O, 160 0 C) → 2NaI + CuI → (+1/2O 2 , 450 0 C) → 2NaI + CuO + 1/2I 2 , NaCuI 2 .4H 2 O → (-4H 2 O, Dried) → NaI + CuI. (auth.)

  18. Adsorption of methyl iodide on charcoal

    International Nuclear Information System (INIS)

    Hidajat, K.; Aracil, J.; Kenney, C.N.

    1990-01-01

    The adsorption of non-radioactive methyl iodide has been measured experimentally over a range of conditions of concentration, and temperature on an activated charcoal. This is of interest since methyl iodide is formed from iodine fission products in gas cooled nuclear reactors. A mathematical model has also been developed which describes the rate of adsorption, under isothermal and linear adsorption isotherm conditions in a recycle adsorber. This model takes into account the resistance to adsorption caused by the surface adsorption, as well as the external and internal mass transfer resistances. The solution to the model for the recycle adsorber was obtained using a semidiscretisation method to reduce the partial differential equations to a system of stiff ordinary differential equations, and the resulting differential equations solved by a standard numerical technique. (author)

  19. Clinical value of sodium iodide symporter

    International Nuclear Information System (INIS)

    Li Qian

    2003-01-01

    The sodium iodide symptorter (NIS) is a membrane glycoprotein that mediates iodide uptake in the thyroid gland and several extrathyroidal tissues. In addition to thyroid tissues, the expression of NIS is found in stomach, prostate, placenta and so on. Radioiodine-concentrating activity in thyroid tissues has allowed the use of radioiodine as a diagnostic and therapeutic agent for patients with thyroid disorders. However, some extrathyroid tissues also take up radioiodine, contributing to unwanted side effects of radioiodine therapy. Now that the molecule of NIS has been cloned and characterized, it may be possible to develop novel strategies to differentially modulate NIS expression and activity, enhancing it in target tissues and impeding it in others. It is also important to explore the use of NIS as an imaging reporter gene to monitor the expression profile of the transgene in transgenic mouse animal models and in patients undergoing gene therapy clinical trials

  20. Methyl iodide tests on used adsorbents

    International Nuclear Information System (INIS)

    Kovach, J.L.

    1993-01-01

    This paper discusses the history of events leading to the current problems in radioiodine test conditions. These radioiodine tests are performed in the adsorbent media from both safety and non-safety related Nuclear Air Treatment Systems (NATS). The main problem addressed is that currently there are still numerous plant technical specifications for NATS which reference outdated test protocols for the surveillance testing of the radioactive methyl iodide performance of the adsorbents. Recommendations for correcting the test condition problems are presented. 7 refs

  1. Investigations on the formation of mercuric thiotungstate and pH-metric determination of the thiotungstate anion

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, S [Paraiba Univ., Joao Pessoa (Brazil). Dept. de Engenharia Quimica

    1981-10-01

    The reaction between mercuric and thiotungstate ions has been followed by means of direct and reverse pH and conductometric titrations in aqueous and aqueous-alcoholic media. The end-points obtained from the sharp inflectons in titration curves occur when molecular ratio of Hg/sup 2 +/ : WS/sub 4//sup 2 -/ is 1 : 1 and correspond to the formation and precipitation of normal mercuric thiotungstate HgS.WS/sub 3/ in the neighbourhood of pH 4.5. The precipitation of this compound has been found to be almost quantitative and the accuracy and reproducibility of the electrometric results are excellent even at low concentrations (1 x 10/sup -3/ M) of the reactants. The pH titrations offer a simple, rapid and accurate method for the determination of the thiotungstate anion as mercuric thiotungstate.

  2. Investigations on the formation of mercuric thiotungstate and pH-metric determination of the thiotungstate anion

    International Nuclear Information System (INIS)

    Prasad, S.

    1981-01-01

    The reaction between mercuric and thiotungstate ions has been followed by means of direct and reverse pH and conductometric titrations in aqueous and aqueous-alcoholic media. The end-points obtained from the sharp inflectons in titration curves occur when molecular ratio of Hg 2+ : WS 4 2- is 1 : 1 and correspond to the formation and precipitation of normal mercuric thiotungstate HgS.WS 3 in the neighbourhood of pH 4.5. The precipitation of this compound has been found to be almost quantitative and the accuracy and reproducibility of the electrometric results are excellent even at low concentrations (1 x 10 -3 M) of the reactants. The pH titrations offer a simple, rapid and accurate method for the determination of the thiotungstate anion as mercuric thiotungstate. (Author) [pt

  3. Mitochondrial bioenergetics during the initiation of mercuric chloride-induced renal injury. I. Direct effects of in vitro mercuric chloride on renal cortical mitochondrial function

    Energy Technology Data Exchange (ETDEWEB)

    Weinberg, J.M. (Veterans Administration Medical Center, Ann Arbor, MI); Harding, P.G.; Humes, H.D.

    1982-01-01

    Increasing data suggest that mitochondrial dysfunction may be an important early component of nephrotoxin-induced changes in renal cell function and viability. This study was designed to obtain more detailed information about the effects on several basic bioenergetic parameters of the direct interaction of Hg/sup 2 +/ with renal cortical mitochondria in vitro as a necessary prelude to studies of mitochondrial functional changes after treatment with mercuric chloride in vivo. Beginning at a threshhold level of 2 nmol of Hg/sup 2 +//mg of mitochondrial protein Hg/sup 2 +/ induced marked stimulation of State 4 respiration, mild inhibition of State 3 respiration, and 2,4-dinitrophenol uncoupled respiration, a striking increase in atractyloside-insensitive ADP uptake and stimulation of both basal- and Mg/sup 2 +/-activated oligomycin-sensitive mitochondrial ATPase activity. These effects of Hg/sup 2 +/ could be prevented and reversed by the sulfhydryl reagent dithioerythritol and by albumin but were not affected by Mg/sup 2 +/. Detailed studies on the addition of HgCl/sub 2/ to the preparation at different stages of the mitochondrial isolation procedure demonstrated that the presence of other proteins decreased mitochondrial Hg/sup 2 +/ binding, that the Hg/sup 2 +/ was not readily washed off the mitochondria by nonprotein-containing solutions, and that prolonged exposure of mitochondria to Hg/sup 2 +/ during the isolation procedure did not markedly alter its functional effects on their reversibility as assessed on the final mitochondrial preparation. These data provide an important basis for critically assessing the changes in function of mitochondria isolated after in vivo treatment with mercuric chloride.

  4. Mercuric dichloride induces DNA damage in human salivary gland tissue cells and lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, Katharina; Kroemer, Susanne [University of Regensburg, Regensburg (Germany); Sassen, Andrea [University of Regensburg, Department of Pathology, Regensburg (Germany); Staudenmaier, Rainer [Technical University of Munich, Department of Otorhinolaryngology, Head and Neck Surgery, Munich (Germany); Reichl, Franz-Xaver [University of Munich, Institute of Pharmacology and Toxicology, Munich (Germany); Harreus, Ulrich [University of Munich, Department of Otorhinolaryngology, Head and Neck Surgery, Munich (Germany); Hagen, Rudolf; Kleinsasser, Norbert [University of Wuerzburg, Department of Otorhinolaryngology, Head and Neck Surgery, Wuerzburg (Germany)

    2007-11-15

    Amalgam is still one of the most frequently used dental filling materials. However, the possible adverse effects especially that of the mercuric component have led to continued controversy. Considering that mercury may be released from amalgam fillings into the oral cavity and also reach the circulating blood after absorption and resorption, it eventually may contribute to tumorigenesis in a variety of target cells. The present investigation focuses on genotoxic effects below a cytotoxic dose level of mercuric dichloride (HgCl{sub 2}) in human samples of salivary glands and lymphocytes to elucidate a possible role in tumor initiation. DNA migration due to single strand breaks, alkali labile sites and incomplete excision repair was quantified with the aid of the single cell microgel electrophoresis (Comet) assay. The concepts of Olive Tail Moment, percentage of DNA in the Tail and Tail Length were used as measures of DNA damage. To control for cytotoxic effects, the trypan blue exclusion test was applied. Human samples of the parotid salivary gland and lymphocytes of ten donors were exposed to HgCl{sub 2} concentrations from 1 to 50 {mu}M. N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and dimethyl sulfoxide (DMSO) served as controls. Increasing dose-dependent DNA migration could be demonstrated after exposure to HgCl{sub 2} in cells of the salivary glands and lymphocytes. In both cell types a significant increase in DNA migration could be shown starting from HgCl{sub 2} concentrations of 5 {mu}M in comparison to the negative control. The viability of the cell systems was not affected except at the highest concentration (50 {mu}M) tested. These data indicate genotoxic effects of mercuric dichloride in human salivary glands and lymphocytes at concentrations not leading to cytotoxic effects or cell death. Consequently, a contributory role in oral salivary gland tumor initiation warrants further investigation. (orig.)

  5. Acute kidney injury and disseminated intravascular coagulation due to mercuric chloride poisoning

    Directory of Open Access Journals (Sweden)

    J Dhanapriya

    2016-01-01

    Full Text Available Mercury is a toxic heavy metal and occurs in organic and inorganic forms. Inorganic mercury includes elemental mercury and mercury salts. Mercury salts are usually white powder or crystals, and widely used in indigenous medicines and folk remedies in Asia. Inorganic mercury poisoning causes acute kidney injury (AKI and gastrointestinal manifestations and can be life-threatening. We describe a case with unknown substance poisoning who developed AKI and disseminated intravascular coagulation (DIC. Renal biopsy showed acute tubular necrosis. Later, the consumed substance was proven to be mercuric chloride. His renal failure improved over time, and his creatinine normalized after 2 months.

  6. Complexo-potentiometric determination of mercury (II) in chlormerodrin and mercuric chloride labelled with radioactive mercury

    International Nuclear Information System (INIS)

    Duek, E.E.

    1976-09-01

    A method is described for determining the amount of mercury (II) in radioactively labelled chlormerodrin and mercuric chloride. By measuring the absolute activity in an ionization chamber, the specific activity is therefore immediately obtained. The determination of Hg (II) is based on a complexometric titration. Because of method characteristics and speed convenience, the end point is observed by means of a pH-meter. A comparison is made with a determination performed by detecting the end point with color-change indicators. The error is estimated, and the results are statistically interpreted. (author) [es

  7. Effect of mercuric chloride intoxication on urinary. gamma. -glutamyl transpeptidase excretion in the sheep

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, F D

    1976-01-01

    The activity of the enzyme ..gamma..-glutamyl transpeptidase (..gamma..-GT) was measured in the urine of sheep. In clinically normal animals the mean value was 6.3 +/- 0.6 mU/ml. In sheep with kidney damage induced by the administration of mercuric chloride there were marked increases in urinary concentrations of ..gamma..-GT, in some cases values in excess of 1000 mU/ml were recorded. This enzyme may be of value in the diagnosis of certain forms of renal disease. 13 references, 1 figure, 1 table.

  8. Effect of tubular damage by mercuric chloride on kidney function and some urinary enzymes in the dog

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, B G; Price, R G; Topham, J C

    1973-01-01

    Alkaline and acid phosphatases, ..beta..-glucosidase, ..beta..-galactosidase, N-acetyl-..beta..-glucosaminidase and lactate dehydrogenase were monitored in the urine and serum of dogs with renal tubular damage induced by a series of increasing doses of mercuric chloride. Evidence is presented that the assay of urinary alkaline and acid phosphatase is the most sensitive method of detecting renal tubular damage in the dog. The clearance of (/sup 14/C)-propranolol was compared before and after the administration of mercuric chloride. In the presence of tubular damage the blood half-life of propranolol and the rate of excretion of metabolites in the urine were increased. 35 references, 7 tables.

  9. Products of the reaction between methylene iodide and tertiary arsines

    International Nuclear Information System (INIS)

    Gigauri, R.D.; Arabuli, L.G.; Machaidze, Z.I.; Rusiya, M.Sh.

    2005-01-01

    Iodides of iodomethylenetrialkyl(aryl) arsonium were synthesized with high yields as a result of interaction between methylene iodide and tertiary arsines. Exchange reactions of the iodides prepared with lead(II) nitrate in water-alcohol solutions gave rise to formation of iodomethylenetrialkyl(aryl) arsonium nitrates. All the products prepared were characterized by data of elementary analysis, IR spectroscopy, conductometry and melting points measurements [ru

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-01

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

  11. In Vitro Bioavailability Study of an Antiviral Compound Enisamium Iodide

    Directory of Open Access Journals (Sweden)

    Eleonore Haltner-Ukomadu

    2018-01-01

    Full Text Available An investigation into the biopharmaceutics classification and a study of the in vitro bioavailability (permeability and solubility of the antiviral compound enisamium iodide (4-(benzylcarbamoyl-1-methylpyridinium iodide were carried out. The solubility of enisamium iodide was determined in four different buffers. Apparent intestinal permeability (Papp of enisamium iodide was assessed using human colon carcinoma (Caco-2 cells at three concentrations. The solubility of enisamium iodide in four buffer solutions from pH 1.2 to 7.5 is about 60 mg/mL at 25 °C, and ranges from 130 to 150 mg/mL at 37 °C, depending on the pH. Based on these results, enisamium iodide can be classified as highly soluble. Enisamium iodide demonstrated low permeability in Caco-2 experiments in all tested concentrations of 10–100 μM with permeability coefficients between 0.2 × 10−6 cm s−1 and 0.3 × 10−6 cm s−1. These results indicate that enisamium iodide belongs to class III of the Biopharmaceutics Classification System (BCS due to its high solubility and low permeability. The bioavailability of enisamium iodide needs to be confirmed in animal and human studies.

  12. Antioxidant effect of Arabic gum against mercuric chloride-induced nephrotoxicity

    Directory of Open Access Journals (Sweden)

    Gado AM

    2013-10-01

    Full Text Available Ali M Gado,1 Badr A Aldahmash21Forensic Medicine and Clinical Toxicology Department, College of Medicine, Tanta University, Tanta, Egypt; 2Medical Laboratory Department, College of Health Sciences, King Saud University, Riyadh, Saudi ArabiaAbstract: The effects of Arabic gum (AG against nephrotoxicity of mercury (Hg, an oxidative-stress inducing substance, in rats were investigated. A single dose of mercuric chloride (5 mg/kg intraperitoneal injection induced renal toxicity, manifested biochemically by a significant increase in serum creatinine, blood urea nitrogen, thiobarbituric acid reactive substances, and total nitrate/nitrite production in kidney tissues. In addition, reduced glutathione, glutathione peroxidase, and catalase enzymes in renal tissues were significantly decreased. Pretreatment of rats with AG (7.5 g/kg/day per oral administration, starting 5 days before mercuric chloride injection and continuing through the experimental period, resulted in a complete reversal of Hg-induced increase in creatinine, blood urea nitrogen, thiobarbituric acid reactive substances, and total nitrate/nitrite to control values. Histopathologic examination of kidney tissues confirmed the biochemical data; pretreatment of AG prevented Hg-induced degenerative changes of kidney tissues. These results indicate that AG is an efficient cytoprotective agent against Hg-induced nephrotoxicity by a mechanism related at least in part to its ability to decrease oxidative and nitrosative stress and preserve the activity of antioxidant enzymes in kidney tissues.Keywords: mercury, acacia gum, oxidative stress, lipid per oxidation, kidney toxicity

  13. Antioxidant effect of Arabic gum against mercuric chloride-induced nephrotoxicity.

    Science.gov (United States)

    Gado, Ali M; Aldahmash, Badr A

    2013-01-01

    The effects of Arabic gum (AG) against nephrotoxicity of mercury (Hg), an oxidative-stress inducing substance, in rats were investigated. A single dose of mercuric chloride (5 mg/kg intraperitoneal injection) induced renal toxicity, manifested biochemically by a significant increase in serum creatinine, blood urea nitrogen, thiobarbituric acid reactive substances, and total nitrate/nitrite production in kidney tissues. In addition, reduced glutathione, glutathione peroxidase, and catalase enzymes in renal tissues were significantly decreased. Pretreatment of rats with AG (7.5 g/kg/day per oral administration), starting 5 days before mercuric chloride injection and continuing through the experimental period, resulted in a complete reversal of Hg-induced increase in creatinine, blood urea nitrogen, thiobarbituric acid reactive substances, and total nitrate/nitrite to control values. Histopathologic examination of kidney tissues confirmed the biochemical data; pretreatment of AG prevented Hg-induced degenerative changes of kidney tissues. These results indicate that AG is an efficient cytoprotective agent against Hg-induced nephrotoxicity by a mechanism related at least in part to its ability to decrease oxidative and nitrosative stress and preserve the activity of antioxidant enzymes in kidney tissues.

  14. Renal effects of in utero exposure to mercuric chloride in rats

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, A.M.; Collette, C.; Lauwerys, R. (Catholic Univ. of Louvain, Industrial Toxicology and Occupational Medicine Unit, Brussels (Belgium))

    1992-08-01

    The transplacental nephrotoxicity of mercuric chloride has been studied in female Sprague-Dawley rats. Mercuric chloride was injected s.c. to rats at the dose of 1 mg/kg during the last 8 gestational days or the whole pregnancy. Both mothers and newborns developed a transient renal dysfunction resulting in an increased urinary excretion of beta[sub 2]-microglobulin and albumin. In mothers and their female offspring, these effects were completely reversible and did not influence the subsequent evolution of the renal function. In the male offspring, however, transitory changes in protein excretion were again observed a few months later, concomitantly with an enhanced accumulation of alpha[sub 2u]-globulin in the kidney. The transfer of mercury from maternal to fetal tissues was very small. The kidney concentrations of mercury in newborns were more than 300 times lower than in mothers. The barrier role of the placenta is not sufficient to prevent the occurrence of renal effects in the offspring of rats treated with inorganic mercury during pregnancy. (orig.).

  15. Calculation of gamma-rays and fast neutrons fluxes with the program Mercure-4

    International Nuclear Information System (INIS)

    Baur, A.; Dupont, C.; Totth, B.

    1978-01-01

    The program MERCURE-4 evaluates gamma ray or fast neutron attenuation, through laminated or bulky three-dimensionnal shields. The method used is that of line of sight point attenuation kernel, the scattered rays being taken into account by means of build-up factors for γ and removal cross sections for fast neutrons. The integration of the point kernel over the range of sources distributed in space and energy, is performed by the Monte-Carlo method, with an automatic adjustment of the importance functions. Since it is operationnal the program MERCURE-4 has been intensively used for many various problems, for example: - the calculation of gamma heating in reactor cores, control rods and shielding screens, as well as in experimental devices and irradiation loops; - the evaluation of fast neutron fluxes and corresponding damage in structural materials of reactors (vessel steels...); - the estimation of gamma dose rates on nuclear instrumentation in the reactors, around the reactor circuits and around spent fuel shipping casks

  16. Analysis for iodide in groundwater by x-ray fluorescence spectrometry after collection as silver iodide on activated charcoal

    International Nuclear Information System (INIS)

    Howe, P.T.

    1980-01-01

    The report describes the determination of microgram quantities of iodide in water by X-ray fluorescence spectrometry. The iodide is concentrated by precipitation as silver iodide on activated charcoal. If a 60-mL sample is available, a concentration of 0.12 mg/L can be detected. Precision (2σ) at the 1-mg/L level is +- 0.08 mg/L. (auth)

  17. Chloride, bromide and iodide scintillators with europium doping

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2014-08-26

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

  18. Methyl iodide retention on charcoal sorbents at parts-per-million concentrations

    International Nuclear Information System (INIS)

    Wood, G.O.; Vogt, G.J.; Kasunic, C.A.

    1978-01-01

    Breakthrough curves for charcoal beds challenged by air containing parts-per-million methyl iodide ( 127 I) vapor concentrations were obtained and analyzed. A goal of this research is to determine if sorbent tests at relatively high vapor concentrations give data that can be extrapolated many orders of magnitude to the region of interest for radioiodine retention and removal. Another objective is to identify and characterize parameters that are critical to the performance of a charcoal bed in a respirator cartridge application. Towards these ends, a sorbent test system was built that allows experimental variations of the parameters of challenge vapor concentration, volumetric flow rate, bed depth, bed diameter, and relative humidity. Methyl iodide breakthrough was measured at a limit of 0.002 ppM using a gas chromatograph equipped with a linearized electron capture detector. Several models that have been proposed to describe breakthrough curves were tested against experimental data. A variety of charcoals used or proposed for use in radioiodine air filtration systems have been tested against 25.7 ppM methyl iodide to obtain these parameters and protection (decomtamination) factors. Effects of challenge concentration, relative humidity, and bed diameter were also investigated. Significant challenge concentration dependence was measured (more efficiency at lower concentration) for two types of charcoals. Increased relative humidity greatly decreased breakthrough times for a given protection factor. Increased bed diameter greatly increased breakthrough times for a given protection factor. Implications of these effects for a test method are discussed

  19. Hepatoprotective and Antioxidant Effect of Mangifera Indica Leaf Extracts against Mercuric Chloride-induced Liver Toxicity in Mice.

    Science.gov (United States)

    Karuppanan, Muthupillai; Krishnan, Manigandan; Padarthi, Pavankumar; Namasivayam, Elangovan

    2014-01-01

    To explore the antioxidant and hepatoprotective effect of ethanolic Mangifera indica (EMI) and methanolic Mangifera indica (MMI) leaf extracts in mercuric chloride (HgCl 2 ) induced toxicity in Swiss albino mice. Toxicity in mice was induced with HgCl 2 (5.0 mg/kg, i.p.), followed by oral intervention with EMI and MMI extracts (25 mg and 50 mg/kg. body wt.) for 30 days. The extent of liver damage was assessed from the extents of histopathological, morphological, antioxidant and liver enzymes. Mercuric chloride-induced mice showed an increased cellular damage whereas leaf extracts of EMI and MMI-treated mice showed recovery of damaged hepatocytes. Mercuric chloride intoxicated mice exhibited a significant (p Mangifera indica extract remarkably reduces hepatotoxicity in mice possibly through its antioxidant potentials. How to cite this article: Karuppanan M, Krishnan M, Padarthi P, Namasivayam E. Hepatoprotec-tive and Antioxidant Effect of Mangifera Indica Leaf Extracts against Mercuric Chloride-induced Liver Toxicity in Mice. Euroasian J Hepato-Gastroenterol 2014;4(1):18-24.

  20. Production of Molecular Iodine and Tri-iodide in the Frozen Solution of Iodide: Implication for Polar Atmosphere.

    Science.gov (United States)

    Kim, Kitae; Yabushita, Akihiro; Okumura, Masanori; Saiz-Lopez, Alfonso; Cuevas, Carlos A; Blaszczak-Boxe, Christopher S; Min, Dae Wi; Yoon, Ho-Il; Choi, Wonyong

    2016-02-02

    The chemistry of reactive halogens in the polar atmosphere plays important roles in ozone and mercury depletion events, oxidizing capacity, and dimethylsulfide oxidation to form cloud-condensation nuclei. Among halogen species, the sources and emission mechanisms of inorganic iodine compounds in the polar boundary layer remain unknown. Here, we demonstrate that the production of tri-iodide (I3(-)) via iodide oxidation, which is negligible in aqueous solution, is significantly accelerated in frozen solution, both in the presence and the absence of solar irradiation. Field experiments carried out in the Antarctic region (King George Island, 62°13'S, 58°47'W) also showed that the generation of tri-iodide via solar photo-oxidation was enhanced when iodide was added to various ice media. The emission of gaseous I2 from the irradiated frozen solution of iodide to the gas phase was detected by using cavity ring-down spectroscopy, which was observed both in the frozen state at 253 K and after thawing the ice at 298 K. The accelerated (photo-)oxidation of iodide and the subsequent formation of tri-iodide and I2 in ice appear to be related with the freeze concentration of iodide and dissolved O2 trapped in the ice crystal grain boundaries. We propose that an accelerated abiotic transformation of iodide to gaseous I2 in ice media provides a previously unrecognized formation pathway of active iodine species in the polar atmosphere.

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

    Science.gov (United States)

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

  2. Photoluminescence Enhancement in Formamidinium Lead Iodide Thin Films

    NARCIS (Netherlands)

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

    2016-01-01

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

  3. The iodine/iodide redox couple at a platinum electrode

    NARCIS (Netherlands)

    Dane, L.M.; Janssen, L.J.J.; Hoogland, J.G.

    1968-01-01

    The I/iodide redox couple was studied on Pt in 0.5M H2SO4 by measuring the impedance as a function of frequency. From these measurements, the exchange c.d. j0 was derived according to Sluyters. The dependence of j0 on the reversible potential and the I and the iodide concns. was established. By

  4. Magnetic detection of mercuric ion using giant magnetoresistance-based biosensing system.

    Science.gov (United States)

    Wang, Wei; Wang, Yi; Tu, Liang; Klein, Todd; Feng, Yinglong; Li, Qin; Wang, Jian-Ping

    2014-04-15

    We have demonstrated a novel sensing strategy employing a giant magnetoresistance (GMR) biosensor and DNA chemistry for the detection of mercuric ion (Hg(2+)). This assay takes advantages of high sensitivity and real-time signal readout of GMR biosensor and high selectivity of thymine-thymine (T-T) pair for Hg(2+). The assay has a detection limit of 10 nM in both buffer and natural water, which is the maximum mercury level in drinking water regulated by U.S. Environmental Protection Agency (EPA). The magnitude of the dynamic range for Hg(2+) detection is up to three orders (10 nM to 10 μM). Herein, GMR sensing technology is first introduced into a pollutant monitoring area. It can be foreseen that the GMR biosensor could become a robust contender in the areas of environmental monitoring and food safety testing.

  5. Expressing a bacterial mercuric ion binding protein in plant for phytoremediation of heavy metals.

    Science.gov (United States)

    Hsieh, Ju-Liang; Chen, Ching-Yi; Chiu, Meng-Hsuen; Chein, Mei-Fang; Chang, Jo-Shu; Endo, Ginro; Huang, Chieh-Chen

    2009-01-30

    A specific mercuric ion binding protein (MerP) originating from transposon TnMERI1 of Bacillus megaterium strain MB1 isolated from Minamata Bay displayed good adsorption capability for a variety of heavy metals. In this study, the Gram-positive MerP protein was expressed in transgenic Arabidopsis to create a model system for phytoremediation of heavy metals. Under control of an actin promoter, the transgenic Arabidpsis showed higher tolerance and accumulation capacity for mercury, cadium and lead when compared with the control plant. Results from confocal microscopy analysis also indicate that MerP was localized at the cell membrane and vesicles of plant cells. The developed transgenic plants possessing excellent metal-accumulative ability could have potential applications in decontamination of heavy metals.

  6. Ferroelastic Fingerprints in Methylammonium Lead Iodide Perovskite

    KAUST Repository

    Hermes, Ilka M.

    2016-02-12

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

  7. Mercury resistance and mercuric reductase activities and expression among chemotrophic thermophilic Aquificae.

    Science.gov (United States)

    Freedman, Zachary; Zhu, Chengsheng; Barkay, Tamar

    2012-09-01

    Mercury (Hg) resistance (mer) by the reduction of mercuric to elemental Hg is broadly distributed among the Bacteria and Archaea and plays an important role in Hg detoxification and biogeochemical cycling. MerA is the protein subunit of the homodimeric mercuric reductase (MR) enzyme, the central function of the mer system. MerA sequences in the phylum Aquificae form the deepest-branching lineage in Bayesian phylogenetic reconstructions of all known MerA homologs. We therefore hypothesized that the merA homologs in two thermophilic Aquificae, Hydrogenobaculum sp. strain Y04AAS1 (AAS1) and Hydrogenivirga sp. strain 128-5-R1-1 (R1-1), specified Hg resistance. Results supported this hypothesis, because strains AAS1 and R1-1 (i) were resistant to >10 μM Hg(II), (ii) transformed Hg(II) to Hg(0) during cellular growth, and (iii) possessed Hg-dependent NAD(P)H oxidation activities in crude cell extracts that were optimal at temperatures corresponding with the strains' optimal growth temperatures, 55°C for AAS1 and 70°C for R1-1. While these characteristics all conformed with the mer system paradigm, expression of the Aquificae mer operons was not induced by exposure to Hg(II) as indicated by unity ratios of merA transcripts, normalized to gyrA transcripts for hydrogen-grown AAS1 cultures, and by similar MR specific activities in thiosulfate-grown cultures with and without Hg(II). The Hg(II)-independent expression of mer in the deepest-branching lineage of MerA from bacteria whose natural habitats are Hg-rich geothermal environments suggests that regulated expression of mer was a later innovation likely in environments where microorganisms were intermittently exposed to toxic concentrations of Hg.

  8. A Vegetable, Launaea taraxacifolia, Mitigated Mercuric Chloride Alteration of the Microanatomy of Rat Brain.

    Science.gov (United States)

    Owoeye, Olatunde; Arinola, Ganiyu O

    2017-11-02

    Mercuric chloride is an environmental pollutant that affects the nervous systems of mammals. Oxidative damage is one of the mechanisms of its toxicity, and antioxidants should mitigate this effect. A vegetable with antioxidant activity is Launaea taraxacifolia, whose ethanolic extract (EELT) was investigated in this experiment to determine its effect against mercuric chloride (MC) intoxication in rat brain. Thirty male Wistar rats were randomly assigned into five groups (n = 6) as follows: control; propylene glycol; EELT (400 mg/kg bwt) for 19 days; MC (HgCl 2 ) (4 mg/bwt) for 5 days from day 15 of the experiment; EELT+ MC, EELT (400 mg/kg bwt) for 14 days + MC (4 mg/bwt) for 5 days from day 15 of the experiment. All treatments were administered orally by gastric gavage. Behavioral tests were conducted on the 20th day, and rats were euthanized the same day. Blood and brain tissue were examined with regard to microanatomical parameters. Data were analyzed using analysis of variance with statistical significance set at p cerebral cortex, dentate gyrus, cornu ammonis 3, and cerebellum of rats. Treatment with EELT prior to MC administration significantly reduced the effect of MC on the hematological, behavioral, and ameliorated histological alterations of the brain. These findings may be attributed partially to the antioxidant property of EELT, which demonstrated protective effects against MC-induced behavioral parameters and alteration of microanatomy of rats' cerebral cortex, hippocampus, and cerebellum. In conclusion, EELT may be a valuable agent for further investigation in the prevention of acute neuropathy caused by inorganic mercury intoxication.

  9. Kinetics of mercury reduction by Serratia marcescens mercuric reductase expressed by pseudomonas putida strains

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.; Deckwer, W.D. [GBF-Gesellschaft fuer Biotechnologische Forschung mbH, Abteilung TU-BCE, Mascheroder Weg 1, D-38124 Braunschweig (Germany)

    2005-10-01

    Mercury (Hg) resistance is widespread among microorganisms and is based on the intracellular transformation of Hg(II) to less toxic elemental Hg(0). The use of microbial consortia to demercurize polluted wastewater streams and environments has been demonstrated. To develop efficient and versatile microbial cleanup strategies requires detailed knowledge of transport and reaction rates. This study focuses on the kinetics of the key enzyme of the microbial transformation, e.g., the mercuric reductase (MerA) under conditions closely resembling the cell interior. To this end, previously constructed and characterized Pseudomonas putida strains expressing MerA from Serratia marcescens were applied. Of the P. putida strains considered in this study P. putida KT2442::mer73 constitutively expressing broad spectrum mercury resistance (merTPAB) yielded the highest mercuric reductase (MerA) activity directly after cell disruption. MerA in the raw extract was further purified (about 100 fold). Reduction rates were measured for various substrates (HgCl{sub 2}, Hg{sub 2}SO{sub 4}, Hg(NO{sub 3}){sub 2} and phenyl mercury acetate) up to high concentrations dependent on the purification grade. In all cases, a pronounced substrate inhibition was found. The kinetic constants determined for the cell raw extract are in agreement with those measured for intact cells. However, the rate data exhibit reduced affinity and inhibition with rising purification grade (specific activity). Therefore, the findings seemingly point to reactions preceding the catalytic reduction. Based on simplified assumptions, a kinetic model is suggested which reasonably describes the experimental findings and can advantageously be applied to the bioreactor design. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  10. Effect of sulfide, selenite and mercuric mercury on the growth and methylation capacity of the sulfate reducing bacterium Desulfovibrio desulfuricans

    Energy Technology Data Exchange (ETDEWEB)

    Truong, Hoang-Yen T. [Department of Biology, Laurentian University, Sudbury, Ontario, Canada P3E 2C6 (Canada); Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada P3E 2C6 (Canada); Chen, Yu-Wei [Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada P3E 2C6 (Canada); Belzile, Nelson, E-mail: nbelzile@laurentian.ca [Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada P3E 2C6 (Canada); Cooperative Freshwater Ecology Unit, Laurentian University, Sudbury, Ontario, Canada P3E 2C6 (Canada)

    2013-04-01

    Cultures of the sulfate reducing bacteria Desulfovibrio desulfuricans were grown under anoxic conditions to study the effect of added sulfide, selenite and mercuric ions. A chemical trap consisting in a CuSO{sub 4} solution was used to control the poisoning effect induced by the bacterial production of hydrogen sulfide via the precipitation of CuS. Following the addition of Hg{sup 2+}, the formation of methylmercury (MeHg) was correlated to bacterial proliferation with most of MeHg found in the culture medium. A large fraction (50–80%) of added Hg{sup 2+} to a culture ended up in a solid phase (Hg{sup 0} and likely HgS) limiting its bioavailability to cells with elemental Hg representing ∼ 40% of the solid. Following the addition of selenite, a small fraction was converted into Se(0) inside the cells and, even though the conversion to this selenium species increased with the increase of added selenite, it never reached more than 49% of the added amount. The formation of volatile dimethylselenide is suggested as another detoxification mechanism. In cultures containing both added selenite and mercuric ions, elemental forms of the two compounds were still produced and the increase of selenium in the residual fraction of the culture suggests the formation of mercuric selenite limiting the bioavailability of both elements to cells. - Highlights: ► Detoxification mechanisms of D. desulfuricans were studied in presence of added sulfide, selenite and mercuric ions. ► The poisoning effect of H{sub 2}S added to or generated by cultures of D. desulfuricans can be controlled with a chemical trap. ► The addition of selenite to cultures triggered the formation of elemental Se and other forms of volatile and non-volatile Se. ► The addition of mercuric ions to cultures led to the production of methylmercury, volatile Hg and solid mercuric sulfide. ► With both Se and Hg added to cultures, fractionation of species in solid and liquid phases suggests the formation of HgSe.

  11. Study of radiation formation of methyl-iodide Part 2

    International Nuclear Information System (INIS)

    Bartonicek, B.; Schweiner, Z.; Bednar, J.; Hladky, E.

    1975-01-01

    Purified methane, ethylene, iodine, methyl iodide, ethyl iodide and hydrogen iodide were irradiated and/or pyrolyzed in Pyrex ampoules by 60 Co-γ-radiation at temperatures between 150 and 450 deg C. The results on radiolysis and pyrolysis were as follows: 1., The most thermally stable product is hydrogen iodide in which already at 450 deg C essen-tially all originally present iodine appears. 2., The radiolytic formation of methyl iodide and hydrogen iodide is positively influenced by the rise in temperature, This and the absolute values of yields indicate a chain mechanism of radiolytic (and pyrolytic) decomposition of the mixture. 3., The ratio of equilibrium concentrations [HI]/[CH 3 I] increases with increasing temperature of pyrolysis showing that HI is the end product of the thermal chain reaction. Methyl iodide is likely to contribute (by its thermal decomposition) to the initiation and propagation of this chain reaction. 4., The negligible temperature dependence of G(H 2 ) and the absence of molecular hydrogen among the products of pyrolytic decomposition of methane-iodine mixtures shows, that (up to 450 deg C) H atoms do not play any role in the thermal chain decomposition of these mixtures. (K.A.)

  12. Flavonoid rutin increases thyroid iodide uptake in rats.

    Directory of Open Access Journals (Sweden)

    Carlos Frederico Lima Gonçalves

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

  13. Mitochondrial bioenergetics during the initiation of mercuric chloride-induced renal activity. II. Functional alterations of renal cortical mitochondria isolated after mercuric chloride treatment

    Energy Technology Data Exchange (ETDEWEB)

    Weinberg, J.M. (Veterans Administration Medical Center, Ann Arbor, MI); Harding, P.G.; Humes, H.D.

    1982-01-01

    The mitochondrial functional defects occurring in the early stages of nephrotoxic renal injury secondary to mercuric chloride have been characterized. No loss of cellular integrity or major mitochondrial structural alterations occurred within the first 3 hr after a subcutaneous injection of 5 mg/kg of HgCl/sub 2/. At 3 h, levels of Hg/sup 2 +/ in renal cortex and isolated renal cortical mitochondria were 1.87 and 0.72 nmol/mg of protein, respectively. Much evidence suggested that this Hg/sup 2 +/ had reached the mitochondria in situ and not during the isolation process. Mitochondria isolated beginning 1 h after treatment with HgCl/sub 2/ showed depressed ADP uptake. At 2 h, inhibitions of State 3 and 2,4-dinitrophenol uncoupled respiration were detected. Inhibition of 2,4-dinitrophenol-activated mitochondrial ATPase activity was present when measured on mitochondria isolated at 3 h. These effects were not reversed by 2 mM dithioerythritol, 50 mg/ml of albumin or 5 mM MgCl/sub 2/. Analysis of the data in the context of information available on the in vitro effects of HgCl/sub 2/ (Weinberg, J.M., Harding, P.G., and Humes, H.D. (1982) J. Biol. Chem. 257, 60-67) indicated that the mitochondrial functional effects could not be attributed to interaction of the mitochondria with Hg/sup 2 +/ during their isolation. These studies implicate compromised mitochondrial bioenergetic function as one of the earliest intracellular effects of Hg/sup 2 +/ in the production of nephrotoxicity but suggest that the intracellular process involves events in addition to those seen with direct exposure of mitochondria to Hg/sup 2 +/ in vitro.

  14. Radiation detectors

    International Nuclear Information System (INIS)

    2013-01-01

    This sixth chapter presents the operational principles of the radiation detectors; detection using photographic emulsions; thermoluminescent detectors; gas detectors; scintillation detectors; liquid scintillation detectors; detectors using semiconductor materials; calibration of detectors; Bragg-Gray theory; measurement chain and uncertainties associated to measurements

  15. Electro regeneration of iodide loaded resin. Contributed Paper RD-18

    International Nuclear Information System (INIS)

    Kumar, Ratnesh; Kumar, T.; Sree Kumar, B.; Seshadri, K.S.; Paul, Biplob

    2014-01-01

    Spent resins generated in the nuclear reactor contain essentially cationic activities due to Cesium, Strontium, Cobalt, and anionic activities due to Iodide, Iodate etc with activity loading to the extent of 0.1 Cim -3 and a surface dose of the order of 5 R. It is necessary to convert the spent resin into innocuous, reusable forms. An attempt has been made to regenerate Iodide containing spent resin into OH - electrolytically by using the OH - produced at the cathode compartment of an electrolytic cell. Results show that the regeneration of the spent resin containing Iodide could be completely accomplished electrolytically more efficiently than by addition of alkali. (author)

  16. 21 CFR 520.763b - Dithiazanine iodide powder.

    Science.gov (United States)

    2010-04-01

    ... therapy for adult worms. (2) The drug is contraindicated in animals sensitive to dithiazanine iodide and...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.763b Dithiazanine...

  17. Growth and characterisation of lead iodide single crystals

    International Nuclear Information System (INIS)

    Tonn, Justus

    2012-01-01

    The work in hand deals with the growth and characterisation of lead iodide (PbI 2 ) single crystals. PbI 2 is regarded as a promising candidate for low-noise X- and gamma ray detection at room temperature. Its benefits if compared to conventional materials like HgI 2 , CdTe, Si, or GaAs lie in a band gap energy of 2.32 eV, an excellent ability to absorb radiation, and a high electrical resistivity. For an application of PbI 2 as detector material the growth and characterisation of crystals with high chemical and structural quality is extremely challenging. In light of this, the effectiveness of zone purification of the PbI 2 used for crystal growth was confirmed by spectroscopic analysis. Furthermore, technological aspects during processing of purified PbI 2 were investigated. With the help of thermal analysis, a correlation was found between the degree of exposing the source material to oxygen from the air and the structural quality of the resulting crystals. A hydrogen treatment was applied to PbI 2 as an effective method for the removal of oxidic pollutions, which resulted in a significant reduction of structural defects like polytypic growth and stress-induced cracking. The growth of PbI 2 single crystals was, among others, carried out by the Bridgman-Stockbarger method. In this context, much effort was put on the investigation of influences resulting from the design and preparation of ampoules. For the first time, crystal growth of PbI 2 was also carried out by the Czochralski method. If compared to the Bridgman-Stockbarger method, the Czochralski technique allowed a significantly faster growth of nearly crack-free crystals with a reproducible predetermination of crystallographic orientation. By an optimised sample preparation of PbI 2 , surface orientations perpendicular to the usually cleaved (0001) plane were realised. It is now possible to determine the material properties along directions which were so far not accessible. Thus, for example, the ratio of

  18. Prevention of organic iodide formation in BWR`s

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-01

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

  19. Accelerated degradation of methyl iodide by agrochemicals.

    Science.gov (United States)

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

    2003-01-29

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

  20. Flavonoids, Thyroid Iodide Uptake and Thyroid Cancer-A Review.

    Science.gov (United States)

    Gonçalves, Carlos F L; de Freitas, Mariana L; Ferreira, Andrea C F

    2017-06-12

    Thyroid cancer is the most common malignant tumor of the endocrine system and the incidence has been increasing in recent years. In a great part of the differentiated carcinomas, thyrocytes are capable of uptaking iodide. In these cases, the main therapeutic approach includes thyroidectomy followed by ablative therapy with radioiodine. However, in part of the patients, the capacity to concentrate iodide is lost due to down-regulation of the sodium-iodide symporter (NIS), the protein responsible for transporting iodide into the thyrocytes. Thus, therapy with radioiodide becomes ineffective, limiting therapeutic options and reducing the life expectancy of the patient. Excessive ingestion of some flavonoids has been associated with thyroid dysfunction and goiter. Nevertheless, studies have shown that some flavonoids can be beneficial for thyroid cancer, by reducing cell proliferation and increasing cell death, besides increasing NIS mRNA levels and iodide uptake. Recent data show that the flavonoids apingenin and rutin are capable of increasing NIS function and expression in vivo. Herein we review literature data regarding the effect of flavonoids on thyroid cancer, besides the effect of these compounds on the expression and function of the sodium-iodide symporter. We will also discuss the possibility of using flavonoids as adjuvants for therapy of thyroid cancer.

  1. Flavonoids, Thyroid Iodide Uptake and Thyroid Cancer—A Review

    Science.gov (United States)

    Gonçalves, Carlos F. L.; de Freitas, Mariana L.; Ferreira, Andrea C. F.

    2017-01-01

    Thyroid cancer is the most common malignant tumor of the endocrine system and the incidence has been increasing in recent years. In a great part of the differentiated carcinomas, thyrocytes are capable of uptaking iodide. In these cases, the main therapeutic approach includes thyroidectomy followed by ablative therapy with radioiodine. However, in part of the patients, the capacity to concentrate iodide is lost due to down-regulation of the sodium-iodide symporter (NIS), the protein responsible for transporting iodide into the thyrocytes. Thus, therapy with radioiodide becomes ineffective, limiting therapeutic options and reducing the life expectancy of the patient. Excessive ingestion of some flavonoids has been associated with thyroid dysfunction and goiter. Nevertheless, studies have shown that some flavonoids can be beneficial for thyroid cancer, by reducing cell proliferation and increasing cell death, besides increasing NIS mRNA levels and iodide uptake. Recent data show that the flavonoids apingenin and rutin are capable of increasing NIS function and expression in vivo. Herein we review literature data regarding the effect of flavonoids on thyroid cancer, besides the effect of these compounds on the expression and function of the sodium-iodide symporter. We will also discuss the possibility of using flavonoids as adjuvants for therapy of thyroid cancer. PMID:28604619

  2. Aqueous-gas phase partitioning and hydrolysis of organic iodides

    International Nuclear Information System (INIS)

    Glowa, G.A.; Wren, J.C.

    2003-01-01

    The volatility and decomposition of organic iodides in a reactor containment building are important parameters to consider when assessing the potential consequences of a nuclear reactor accident. However, there are few experimental data available for the volatilities (often reported as partition coefficients) or few rate constants regarding the decomposition (via hydrolysis) of organic iodides. The partition coefficients and hydrolysis rate constants of eight organic iodides, having a range of molecular structures, have been measured in the current studies. This data, and data accumulated in the literature, have been reviewed and discussed to provide guidelines for appropriate organization of organic iodides for the purpose of modelling iodine behaviour under postulated nuclear reactor accident conditions. After assessment of the partition coefficients and their temperature dependences of many classes of organic compounds, it was found that organic iodides could be divided into two categories based upon their volatility relative to molecular iodine. Similarly, hydrolysis rates and their temperature dependences are assigned to the two categories of organic iodides. (author)

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

    DEFF Research Database (Denmark)

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

    2006-01-01

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

  4. The 11C-radioisotopic study of methanol conversion on V-MCM-41; the influence of methyl iodide on the transformation

    International Nuclear Information System (INIS)

    Sarkadi-Priboczki, E.; Szelecsenyi, F.; Kovacs, Z.; Solmaz, A.; Balci, S.; Dogu, T.

    2007-01-01

    Complete text of publication follows. The MCM-41 mesoporous material has Lewis and even Bronsted acid sites to produce dimethyl ether with some hydrocarbons, while over metal modified MCM-41 mostly formaldehyde and dimethoxy methane (i.e. methylal) or methyl formate are produced. In present experiments V incorporated basically mild acid sites of MCM-41 was prepared by low temperature direct synthesis. The V-MCM-41 has enough main active Lewis sites (by V-) to form formaldehyde and also light Bronsted acid sites to let the adsorbed formaldehyde eliminate and afterwards, with methanol, to form dimethoxy methane in nonoxidative environment. This V-MCM-41 has been tested by ethanol conversion in non-oxidative environments too and diethoxy methane as main product was detected. In present work the methanol conversion, as well as the methanol co-reaction with methyl iodide are studied from the same V-MCM-41 sample using 11 C-technique. The 11 C-labelled radioactive methanol has been already applied for determination of methanol conversion rates on Cu-modified MCM-41. The V-MCM-41 was prepared by direct hydrothermal synthesis method. The adsorption rate of 11 C-methanol and, after the reaction, the desorption rate of the remaining 11 C-derivatives on catalyst were continuously detected by gamma detectors. The derivatives were analyzed by radio-gas chromatography (gas chromatograph with FID coupled on-line with a radioactivity detector). Both dimethyl ether and hydrocarbon formation are also in slight degrees according to weak Lewis and Bronsted acidities. Since the conversion was carried out without added oxygen gas, only the frame oxygen can take part into catalysis. In presence of non-radioactive methyl iodide, the radioactive methanol is converted to radioactive methyl iodide on V-MCM-41. The radio-GC analysis confirmed that the iodide induced change of the reaction performance was reversible i.e. the radioactive methyl iodide was regenerated to non-radioactive methyl

  5. Formamidinium iodide: crystal structure and phase transitions

    Directory of Open Access Journals (Sweden)

    Andrey A. Petrov

    2017-04-01

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

  6. Distribution of biotransformation of methyl mercuric chloride in different tissues of mice

    International Nuclear Information System (INIS)

    Mehra, M.; Choi, B.H.

    1981-01-01

    The distribution of 203 Hg radioactivity has been studied in various organs of adult male and female mice from one hour to 21 days after treating with 203 Hg-labeled methyl mercuric chloride (MMC). The amount of methyl mercury (MeHg) and inorganic mercury (Hg) has also beam determined by injecting single doses of non-radioactive MMC, and subsequently measuring total, organic and inorganic Hg content by atomic absorption technique. In addition, photoemulsion histochemical method (PEHM) was used to demonstrate localization of Hg grains in various cellular compartments of organs and tissues. The highest levels of radioactivity were attained at 7 hours post-treatment on all organs except for brain and testis. The testis showed the highest radioactivity at one day and the brain at two days post-treatment. MeHg persisted in brain over a longer period though the level was not as high. The content of MeHg and inorganic Hg was maximum in kidneys as compared to other organs. The brain and the reproductive organs contained the least amoun of inorganic Hg. By PEHM, Hg grains were most prominently observed in the sinusoids, Kupfer cells, hepatic cells and bile duct epithelium of liver; in the lumen of blood vessels, convoluted and collecting tubules of kidneys; and in the gastrointestinal epithelium. The pattern of uptake and distribution of MeHg correlated well with the morphological demonstration of Hg grains in tissue sections. (author)

  7. Mercury Disposition in Suckling Rats: Comparative Assessment Following Parenteral Exposure to Thiomersal and Mercuric Chloride

    Science.gov (United States)

    Blanuša, Maja; Orct, Tatjana; Vihnanek Lazarus, Maja; Sekovanić, Ankica; Piasek, Martina

    2012-01-01

    Due to the facts that thiomersal-containing vaccine is still in use in many developing countries, and all forms of mercury have recognised neurotoxic, nephrotoxic, and other toxic effects, studies on disposition of ethylmercury and other mercury forms are still justified, especially at young age. Our investigation aimed at comparing mercury distribution and rate of excretion in the early period of life following exposure to either thiomersal (TM) or mercuric chloride (HgCl2) in suckling rats. Three experimental groups were studied: control, TM, and HgCl2, with 12 to18 pups in each. Both forms of mercury were administered subcutaneously in equimolar quantities (0.81 μmol/kg b.w.) three times during the suckling period (on the days of birth 7, 9, and 11) to mimic the vaccination regimen in infants. After the last administration of TM or HgCl2, total mercury retention and excretion was assessed during following six days. In TM-exposed group mercury retention was higher in the brain, enteral excretion was similar, and urinary excretion was much lower compared to HgCl2-exposed sucklings. More research is still needed to elucidate all aspects of toxicokinetics and most harmful neurotoxic potential of various forms of mercury, especially in the earliest period of life. PMID:22899883

  8. Mechanism of inhibition of rat brain adenosine triphosphatase by mercuric chloride

    International Nuclear Information System (INIS)

    Chetty, C.S.; Rajanna, B.; Rajanna, S.

    1989-01-01

    Mercuric Chloride (Hg), a neurotoxic compound inhibited ATPase system of rat brain microsomes. Membrane bound enzymes, Na + -K + ATPase (IC 50 = 2.35 x 10 -7M ) and K-paranitrophenyl phosphatase (K-PNPPase) (IC 50 = 2.7 x 10 -7M ) and 3 H-Ouabain binding (IC 50 = 3.3 x 10 -7M ) were inhibited by Hg at micromolar concentrations in a dose dependent manner. Hydrolysis of ATP was linear with time with or without Hg in the reaction mixtures. Altered pH or temperature versus enzyme activity showed higher inhibition by Hg at basic pH (8.0-9.0) and at lower temperatures (17-32 degree C). Activation energy (ΔE) values were increased at 27-37 degree C in the presence of Hg. Kinetic studies of cationic-substrate activation of Na + -K + ATPase and K-PNPPase in the presence of Hg showed significant changes in kinetic constant (K m and V max ). Inhibition of Na + -K + ATPase was partially restored by repeated washings of microsomes. Preincubation with sulfhydryl agents protected Na + -K + ATPase from Hg inhibition. Cumulative inhibition studies with Hg and ouabain indicated possible interaction between the two inhibitors of Na + -K + ATPase by interacting at Na + and K + sites

  9. Effect of mercuric chloride feeding on sexual maturity, egg production and fertility in Japanese quail

    Science.gov (United States)

    Hill, E.F.; Shaffner, C.S.

    1973-01-01

    Japanese quail (Coturnix c. japonica) were fed 0, 8, 16 or 32 p.p.m. of mercury as mercuric chloride from 3 days of age through 20 weeks of age. The onset of egg production generally occurred earlier for hens fed HgCl2. Average age in days at first oviposition for the control, 8 p.p.m., 16 p.p.m. and 32 p.p.m. was 48.4, 50.9, 46.9 and 44.0 respectively. The average rate of egg productivity from first oviposition to attainment of full growth (9 weeks of age) correlated positively with in increased dietary mercury (controls, 8 p.p.m., 16 p.p.m., 32 p.p.m. ? 75.2, 69.3, 86.1 and 93.3% respectively). By 20 weeks of age productivity was 81.0, 80.6, 87.5 and 92.9% for control, 8, 16 and 32 p.p.m. groups respectively. Fertility was depressed when hens were fed HgCl2. At 9 weeks of age average control fertility was 59% contrasted with 25% for the 32 p.p.m. group. At 12 weeks fertility increased to 89% and 57% for these groups. From this study it is apparent. that the onset and rate of egg production was stimulated by HgCl2, but fertility was adversely affected.

  10. MERCURE-3, Gamma Attenuation by Line-of-Flight in 3-D Heterogeneous Geometry

    International Nuclear Information System (INIS)

    Devillers, C.; Szondi, Egon J.

    1995-01-01

    1 - Nature of physical problem solved: MERCURE-3/PC performs three- dimensional gamma shielding calculations around extended gamma sources. These may be even non-homogeneous. 2 - Method of solution: The algorithm of the code is the point kernel integration model combined with buildup calculations. The geometry can be described analytically using linear and quadratic surfaces of any type. A standard gamma cross section library is provided with the code. 3 - Restrictions on the complexity of the problem: To make possible the solution of large problems, all the problem size-dependent arrays are declared using symbolic constants. The default values are sufficient for most of the practical problems (e.g. 100 space elements; 100 equations; 300 surface elements; 40 materials; 25 energy groups, etc.); the code uses in this case only 200-250 Kbytes of memory, depending on the compiler used. If the problem is very large, the symbolic constants have to be modified, and the code has to be compiled using the Lahey F77L3 (protected mode) compiler

  11. Ionization detector

    International Nuclear Information System (INIS)

    Steele, D.S.

    1987-01-01

    An ionization detector having an array of detectors has, for example, grounding pads positioned in the spaces between some detectors (data detectors) and other detectors (reference detectors). The grounding pads are kept at zero electric potential, i.e. grounded. The grounding serves to drain away electrons and thereby prevent an unwanted accumulation of charge in the spaces, and cause the electric field lines to be more perpendicular to the detectors in regions near the grounding pads. Alternatively, no empty space is provided there being additional, grounded, detectors provided between the data and reference detectors. (author)

  12. Observation of Cherenkov rings using a low-pressure parallel-plate chamber and a solid cesium-iodide photocathode

    International Nuclear Information System (INIS)

    Lockyer, N.S.; Millan, J.E.; Lu, C.; McDonald, K.T.; Lopez, A.

    1993-01-01

    We have observed Cherenkov rings from minimum-ionizing particles using a low-pressure, parallel-plate pad-chamber with a cesium-iodide solid photocathode. This detector is blind to minimum-ionizing particles, and sensitive to Cherenkov photons of wavelengths 170-210 nm. An average of 5 photoelectrons per Cherenkov ring were detected using a 2-cm-thick radiator of liquid C 6 F 14 . This paper reports on the chamber construction, photocathode preparation and testbeam results. (orig.)

  13. Standard free energy of formation of iron iodide

    Science.gov (United States)

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

    1983-01-01

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

  14. Study on gold concentrate leaching by iodine-iodide

    Science.gov (United States)

    Wang, Hai-xia; Sun, Chun-bao; Li, Shao-ying; Fu, Ping-feng; Song, Yu-guo; Li, Liang; Xie, Wen-qing

    2013-04-01

    Gold extraction by iodine-iodide solution is an effective and environment-friendly method. In this study, the method using iodine-iodide for gold leaching is proved feasible through thermodynamic calculation. At the same time, experiments on flotation gold concentrates were carried out and encouraging results were obtained. Through optimizing the technological conditions, the attained high gold leaching rate is more than 85%. The optimum process conditions at 25°C are shown as follows: the initial iodine concentration is 1.0%, the iodine-to-iodide mole ratio is 1:8, the solution pH value is 7, the liquid-to-solid mass ratio is 4:1, the leaching time is 4 h, the stirring intensity is 200 r/mim, and the hydrogen peroxide consumption is 1%.

  15. A novel mercuric reductase from the unique deep brine environment of atlantis II in the red sea

    KAUST Repository

    Sayed, Ahmed Anazadeh

    2013-11-26

    Aunique combination of physicochemical conditions prevails in the lower convective layer (LCL) of the brine pool at Atlantis II (ATII) Deep in the Red Sea. With a maximum depth of over 2000 m, the pool is characterized by acidic pH (5.3), high temperature (68 °C), salinity (26%), low light levels, anoxia, and high concentrations of heavy metals. We have established a metagenomic dataset derived from the microbial community in the LCL, and here we describe a gene for a novel mercuric reductase, a key component of the bacterial detoxification system for mercuric and organomercurial species. The metagenome-derived gene and an ortholog from an uncultured soil bacterium were synthesized and expressed in Escherichia coli. The properties of their products show that, in contrast to the soil enzyme, the ATII-LCL mercuric reductase is functional in high salt, stable at high temperatures, resistant to high concentrations of Hg2+, and efficiently detoxifies Hg2+ in vivo. Interestingly, despite the marked functional differences between the orthologs, their amino acid sequences differ by less than 10%. Site-directed mutagenesis and kinetic analysis of the mutant enzymes, in conjunction with three-dimensional modeling, have identified distinct structural features that contribute to extreme halophilicity, thermostability, and high detoxification capacity, suggesting that these were acquired independently during the evolution of this enzyme. Thus, our work provides fundamental structural insights into a novel protein that has undergone multiple biochemical and biophysical adaptations to promote the survival of microorganisms that reside in the extremely demanding environment of the ATII-LCL. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Toxicological Significance of Renal Bcrp: Another Potential Transporter in the Elimination of Mercuric Ions from Proximal Tubular Cells

    Science.gov (United States)

    Bridges, Christy C.; Zalups, Rudolfs K.; Joshee, Lucy

    2015-01-01

    Secretion of inorganic mercury (Hg2+) from proximal tubular cells into the tubular lumen has been shown to involve the multidrug resistance-associated protein 2 (Mrp2). Considering similarities in localization and substrate specificity between Mrp2 and the breast cancer resistance protein (Bcrp), we hypothesize that Bcrp may also play a role in the proximal tubular secretion of mercuric species. In order to test this hypothesis, the uptake of Hg2+ was examined initially using inside-out membrane vesicles containing Bcrp. The results of these studies suggest that Bcrp may be capable of transporting certain conjugates of Hg2+. To further characterize the role of Bcrp in the handling of mercuric ions and in the induction of Hg2+-induced nephropathy, Sprague-Dawley and Bcrp knockout (bcrp−/−) rats were exposed intravenously to a non-nephrotoxic (0.5 μmol • kg−1), a moderately nephrotoxic (1.5 μmol • kg−1) or a significantly nephrotoxic (2.0 μmol • kg−1) dose of HgCl2. In general, the accumulation of Hg2+ was greater in organs of bcrp−/− rats than in Sprague-Dawley rats, suggesting that Bcrp may play a role in the export of Hg2+ from target cells. Within the kidney, cellular injury and necrosis was more severe in bcrp−/− rats than in controls. The pattern of necrosis, which was localized in the inner cortex and the outer stripe of the outer medulla was significantly different from that observed in Mrp2-deficient animals. These findings suggest that Bcrp may be involved in the cellular export of select mercuric species and that its role in this export may differ from that of Mrp2. PMID:25868844

  17. MRP2 and the Handling of Mercuric Ions in Rats Exposed Acutely to Inorganic and Organic Species of Mercury

    Science.gov (United States)

    Bridges, Christy C.; Joshee, Lucy; Zalups, Rudolfs K.

    2011-01-01

    Mercuric ions accumulate preferentially in renal tubular epithelial cells and bond with intracellular thiols. Certain metal-complexing agents have been shown to promote extraction of mercuric ions via the multidrug resistance-associated protein 2 (MRP2). Following exposure to a non-toxic dose of inorganic mercury (Hg2+), in the absence of complexing agents, tubular cells are capable of exporting a small fraction of intracellular Hg2+ through one or more undetermined mechanisms. We hypothesize that MRP2 plays a role in this export. To test this hypothesis, Wistar (control) and TR− rats were injected intravenously with a non-nephrotoxic dose of HgCl2 (0.5 μmol/kg) or CH3HgCl (5 mg/kg), containing [203Hg], in the presence or absence of cysteine (Cys; 1.25 μmol/kg or 12.5 mg/kg, respectively). Animals were sacrificed 24 h after exposure to mercury and the content of [203Hg] in blood, kidneys, liver, urine and feces was determined. In addition, uptake of Cys-S-conjugates of Hg2+ and methylmercury (CH3Hg+) was measured in inside-out membrane vesicles prepared from either control Sf9 cells or Sf9 cells transfected with human MRP2. The amount of mercury in the total renal mass and liver was significantly greater in TR− rats than in controls. In contrast, the amount of mercury in urine and feces was significantly lower in TR− rats than in controls. Data from membrane vesicles indicate that Cys-S-conjugates of Hg2+ and CH3Hg+ are transportable substrates of MRP2. Collectively, these data indicate that MRP2 plays a role in the physiological handling and elimination of mercuric ions from the kidney. PMID:21134393

  18. Mutagenesis of the redox-active disulfide in mercuric ion reductase: Catalysis by mutant enzymes restricted to flavin redox chemistry

    International Nuclear Information System (INIS)

    Distefano, M.D.; Au, K.G.; Walsh, C.T.

    1989-01-01

    Mercuric reductase, a flavoenzyme that possesses a redox-active cystine, Cys 135 Cys 140 , catalyzes the reduction of Hg(II) to Hg(0) by NADPH. As a probe of mechanism, the authors have constructed mutants lacking a redox-active disulfide by eliminating Cys 135 (Ala 135 Cys 140 ), Cys 14 (Cys 135 Ala 140 ), or both (Ala 135 Ala 140 ). Additionally, they have made double mutants that lack Cys 135 (Ala 135 Cys 139 Cys 140 ) or Cys 140 (Cys 135 Cys 139 Ala 140 ) but introduce a new Cys in place of Gly 139 with the aim of constructing dithiol pairs in the active site that do not form a redox-active disulfide. The resulting mutant enzymes all lack redox-active disulfides and are hence restricted to FAD/FADH 2 redox chemistry. Each mutant enzyme possesses unique physical and spectroscopic properties that reflect subtle differences in the FAD microenvironment. Preliminary evidence for the Ala 135 Cys 139 Cys 14 mutant enzyme suggests that this protein forms a disulfide between the two adjacent Cys residues. Hg(II) titration experiments that correlate the extent of charge-transfer quenching with Hg(II) binding indicate that the Ala 135 Cys 140 protein binds Hg(II) with substantially less avidity than does the wild-type enzyme. All mutant mercuric reductases catalyze transhydrogenation and oxygen reduction reactions through obligatory reduced flavin intermediates at rates comparable to or greater than that of the wild-type enzyme. In multiple-turnover assays which monitored the production of Hg(0), two of the mutant enzymes were observed to proceed through at least 30 turnovers at rates ca. 1000-fold slower than that of wild-type mercuric reductase. They conclude that the Cys 135 and Cys 140 thiols serve as Hg(II) ligands that orient the Hg(II) for subsequent reduction by a reduced flavin intermediate

  19. A novel mercuric reductase from the unique deep brine environment of atlantis II in the red sea

    KAUST Repository

    Sayed, Ahmed Anazadeh; Ghazy, Mohamed A.; Ferreira, Ari José Scattone; Setú bal, Joã o Carlos; Chambergo, Felipe Santiago; Ouf, Amged; Adel, Mustafa; Dawe, Adam Sean; Archer, John A.C.; Bajic, Vladimir B.; Siam, Rania; El-Dorry, Hamza A A

    2013-01-01

    Aunique combination of physicochemical conditions prevails in the lower convective layer (LCL) of the brine pool at Atlantis II (ATII) Deep in the Red Sea. With a maximum depth of over 2000 m, the pool is characterized by acidic pH (5.3), high temperature (68 °C), salinity (26%), low light levels, anoxia, and high concentrations of heavy metals. We have established a metagenomic dataset derived from the microbial community in the LCL, and here we describe a gene for a novel mercuric reductase, a key component of the bacterial detoxification system for mercuric and organomercurial species. The metagenome-derived gene and an ortholog from an uncultured soil bacterium were synthesized and expressed in Escherichia coli. The properties of their products show that, in contrast to the soil enzyme, the ATII-LCL mercuric reductase is functional in high salt, stable at high temperatures, resistant to high concentrations of Hg2+, and efficiently detoxifies Hg2+ in vivo. Interestingly, despite the marked functional differences between the orthologs, their amino acid sequences differ by less than 10%. Site-directed mutagenesis and kinetic analysis of the mutant enzymes, in conjunction with three-dimensional modeling, have identified distinct structural features that contribute to extreme halophilicity, thermostability, and high detoxification capacity, suggesting that these were acquired independently during the evolution of this enzyme. Thus, our work provides fundamental structural insights into a novel protein that has undergone multiple biochemical and biophysical adaptations to promote the survival of microorganisms that reside in the extremely demanding environment of the ATII-LCL. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. A novel mercuric reductase from the unique deep brine environment of Atlantis II in the Red Sea.

    Science.gov (United States)

    Sayed, Ahmed; Ghazy, Mohamed A; Ferreira, Ari J S; Setubal, João C; Chambergo, Felipe S; Ouf, Amged; Adel, Mustafa; Dawe, Adam S; Archer, John A C; Bajic, Vladimir B; Siam, Rania; El-Dorry, Hamza

    2014-01-17

    A unique combination of physicochemical conditions prevails in the lower convective layer (LCL) of the brine pool at Atlantis II (ATII) Deep in the Red Sea. With a maximum depth of over 2000 m, the pool is characterized by acidic pH (5.3), high temperature (68 °C), salinity (26%), low light levels, anoxia, and high concentrations of heavy metals. We have established a metagenomic dataset derived from the microbial community in the LCL, and here we describe a gene for a novel mercuric reductase, a key component of the bacterial detoxification system for mercuric and organomercurial species. The metagenome-derived gene and an ortholog from an uncultured soil bacterium were synthesized and expressed in Escherichia coli. The properties of their products show that, in contrast to the soil enzyme, the ATII-LCL mercuric reductase is functional in high salt, stable at high temperatures, resistant to high concentrations of Hg(2+), and efficiently detoxifies Hg(2+) in vivo. Interestingly, despite the marked functional differences between the orthologs, their amino acid sequences differ by less than 10%. Site-directed mutagenesis and kinetic analysis of the mutant enzymes, in conjunction with three-dimensional modeling, have identified distinct structural features that contribute to extreme halophilicity, thermostability, and high detoxification capacity, suggesting that these were acquired independently during the evolution of this enzyme. Thus, our work provides fundamental structural insights into a novel protein that has undergone multiple biochemical and biophysical adaptations to promote the survival of microorganisms that reside in the extremely demanding environment of the ATII-LCL.

  1. Silicon detectors

    International Nuclear Information System (INIS)

    Klanner, R.

    1984-08-01

    The status and recent progress of silicon detectors for high energy physics is reviewed. Emphasis is put on detectors with high spatial resolution and the use of silicon detectors in calorimeters. (orig.)

  2. Synthesis of carbon nanoparticles using one step green approach and their application as mercuric ion sensor

    Energy Technology Data Exchange (ETDEWEB)

    Roshni, V.; Ottoor, Divya, E-mail: divya@chem.unipune.ac.in

    2015-05-15

    Carbon nanoparticles (CNPs) have been evolved as a promising candidate for the metal sensing applications due to their synthesis from naturally occurring and easily available non-toxic molecular precursors by green chemistry. A simple and one step procedure is reported here for the synthesis of CNPs from coconut milk by thermal pyrolysis at a temperature of 120–150 °C for 2–5 min without using any carbonizing or passivating agent. On pyrolysis the coconut oil is separated from the carbon rich residue and the residue when dissolved in water showed blue fluorescence under UV light. The CNPs produced are found to show an emission maximum at 440 nm when excited at 360 nm. Synthesis by green approach makes CNPs a promising substitute for the metal sensing applications. Series of metal ions which have a hazardous impact on the ecological system have been taken for the analysis and it is observed that the fluorescence of CNPs gets remarkably quenched by mercuric ions. Fluorescence quenching was studied using standard Stern–Volmer quenching model. Limit of detection was found to be 16.5 nM Hg{sup 2+} concentration. - Highlights: • Green and economical synthesis of carbon nanoparticles (CNPs) from naturally abundant material. • Coconut milk is used as molecular precursor, which on thermal pyrolysis at 120 °C yielded CNPs. • Highly fluorescent CNPs show an emission maxima of 440 nm when excited at 360 nm. • Application of CNPs for metal ion sensing using fluorescence quenching phenomena. • Hg{sup 2+} is most effectively sensed with a detection limit of 16.5 nM.

  3. L-cysteine protected copper nanoparticles as colorimetric sensor for mercuric ions.

    Science.gov (United States)

    Soomro, Razium A; Nafady, Ayman; Sirajuddin; Memon, Najma; Sherazi, Tufail H; Kalwar, Nazar H

    2014-12-01

    This report demonstrates a novel, simple and efficient protocol for the synthesis of copper nanoparticles in aqueous solution using L-cysteine as capping or protecting agent. UV-visible (UV-vis) spectroscopy was employed to monitor the LSPR band of L-cysteine functionalized copper nanoparticles (Cyst-Cu NPs) based on optimizing various reaction parameters. Fourier Transform Infrared (FTIR) spectroscopy provided information about the surface interaction between L-cysteine and Cu NPs. Transmission Electron Microscopy (TEM) confirmed the formation of fine spherical, uniformly distributed Cyst-Cu NPs with average size of 34 ± 2.1 nm. X-ray diffractometry (XRD) illustrated the formation of pure metallic phase crystalline Cyst-Cu NPs. As prepared Cyst-Cu NPs were tested as colorimetric sensor for determining mercuric (Hg(2+)) ions in an aqueous system. Cyst-Cu NPs demonstrated very sensitive and selective colorimetric detection of Hg(2+) ions in the range of 0.5 × 10(-6)-3.5 × 10(-6) mol L(-1) based on decrease in LSPR intensity as monitored by a UV-vis spectrophotometer. The developed sensor is simple, economic compared to those based on precious metal nanoparticles and sensitive to detect Hg(2+) ions with detection limit down to 4.3 × 10(-8) mol L(-1). The sensor developed in this work has a high potential for rapid and on-site detection of Hg(2+) ions. The sensor was successfully applied for assessment of Hg(2+) ions in real water samples collected from various locations of the Sindh River. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Synthesis of carbon nanoparticles using one step green approach and their application as mercuric ion sensor

    International Nuclear Information System (INIS)

    Roshni, V.; Ottoor, Divya

    2015-01-01

    Carbon nanoparticles (CNPs) have been evolved as a promising candidate for the metal sensing applications due to their synthesis from naturally occurring and easily available non-toxic molecular precursors by green chemistry. A simple and one step procedure is reported here for the synthesis of CNPs from coconut milk by thermal pyrolysis at a temperature of 120–150 °C for 2–5 min without using any carbonizing or passivating agent. On pyrolysis the coconut oil is separated from the carbon rich residue and the residue when dissolved in water showed blue fluorescence under UV light. The CNPs produced are found to show an emission maximum at 440 nm when excited at 360 nm. Synthesis by green approach makes CNPs a promising substitute for the metal sensing applications. Series of metal ions which have a hazardous impact on the ecological system have been taken for the analysis and it is observed that the fluorescence of CNPs gets remarkably quenched by mercuric ions. Fluorescence quenching was studied using standard Stern–Volmer quenching model. Limit of detection was found to be 16.5 nM Hg 2+ concentration. - Highlights: • Green and economical synthesis of carbon nanoparticles (CNPs) from naturally abundant material. • Coconut milk is used as molecular precursor, which on thermal pyrolysis at 120 °C yielded CNPs. • Highly fluorescent CNPs show an emission maxima of 440 nm when excited at 360 nm. • Application of CNPs for metal ion sensing using fluorescence quenching phenomena. • Hg 2+ is most effectively sensed with a detection limit of 16.5 nM

  5. Exposure to mercuric chloride induces developmental damage, oxidative stress and immunotoxicity in zebrafish embryos-larvae.

    Science.gov (United States)

    Zhang, Qun-Fang; Li, Ying-Wen; Liu, Zhi-Hao; Chen, Qi-Liang

    2016-12-01

    Mercury (Hg) is a widespread environmental pollutant that can produce severe negative effects on fish even at very low concentrations. However, the mechanisms underlying inorganic Hg-induced oxidative stress and immunotoxicity in the early development stage of fish still need to be clarified. In the present study, zebrafish (Danio rerio) embryos were exposed to different concentrations of Hg 2+ (0, 1, 4 and 16μg/L; added as mercuric chloride, HgCl 2 ) from 2h post-fertilization (hpf) to 168hpf. Developmental parameters and total Hg accumulation were monitored during the exposure period, and antioxidant status and the mRNA expression of genes related to the innate immune system were examined at 168hpf. The results showed that increasing Hg 2+ concentration and time significantly increased total Hg accumulation in zebrafish embryos-larvae. Exposure to 16μg/L Hg 2+ caused developmental damage, including increased mortality and malformation, decreased body length, and delayed hatching period. Meanwhile, HgCl 2 exposure (especially in the 16μg/L Hg 2+ group) induced oxidative stress affecting antioxidant enzyme (CAT, GST and GPX) activities, endogenous GSH and MDA contents, as well as the mRNA levels of genes (cat1, sod1, gstr, gpx1a, nrf2, keap1, hsp70 and mt) encoding antioxidant proteins. Moreover, the transcription levels of several representative genes (il-1β, il-8, il-10, tnfα2, lyz and c3) involved in innate immunity were up-regulated by HgCl 2 exposure, suggesting that inorganic Hg had the potential to induce immunotoxicity. Taken together, the present study provides evidence that waterborne HgCl 2 exposure can induce developmental impairment, oxidative stress and immunotoxicity in the early development stage of fish, which brings insights into the toxicity mechanisms of inorganic Hg in fish. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Instrumentation For Multiple Radiation Detection Based On Novel Mercurous Halides For Nuclear Planetology, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Radiation detectors that sense gamma and neutron radiation are critical to the exploration of planetary surface composition. Among the key technological challenges...

  7. Experimental studies of caesium iodide aerosol condensation: theoretical interpretation

    International Nuclear Information System (INIS)

    Beard, A.M.; Benson, C.G.; Horton, K.D.; Buckle, E.R.

    1990-07-01

    Caesium iodide is predicted to be a significant source of fission product aerosols during the course of a severe accident in a pressurised water reactor (PWR). The nucleation and growth of caesium iodide aerosols have been studied using a plume chamber and the results compared with theoretical values calculated using the approach developed by Buckle for aerosol nucleation. The morphology of the particles was studied using scanning electron microscopy (SEM) and transmission optical microscopy (TOM), whilst the particle size distributions were determined from differential mobility (DMPS) and aerodynamic (APS) measurements. (author)

  8. Electronic properties and Compton profiles of silver iodide

    Indian Academy of Sciences (India)

    We have carried out an extensive study of electronic properties of silver iodide in - and -phases. The theoretical Compton profiles, energy bands, density of states and anisotropies in momentum densities are computed using density functional theories. We have also employed full-potential linearized augmented ...

  9. Effects of Potassium Iodide on Low Avid Immunological Reactions ...

    African Journals Online (AJOL)

    In identical test conditions keeping appropriate control, the following ... Abstract. Background: Selective in‑vivo anti‑fungal action of potassium iodide (KI) is an enigma, but .... mechanism of action of the drug against selective infections. In fact, if ...

  10. Research on solubility characteristics of gaseous methyl iodide

    International Nuclear Information System (INIS)

    Zhou Yanmin; Sun Zhongning; Gu Haifeng; Wang Junlong

    2014-01-01

    With the deionized water as the absorbent, the solubility characteristics of the gaseous methyl iodide were studied under different temperature and pressure conditions, using a dynamic measuring method. The results show that within the range of experiment parameters, namely temperature is below 80℃ and pressure is lower than 0.3 MPa, the physical dissolution process of gaseous methyl iodide in water obeys Henry's law. The solubility coefficient under different temperature and pressure conditions was calculated based on the measurement results. Further research indicates that at atmospheric pressure, the solubility coefficient of methyl iodide in water decreases exponentially with the increase of temperature. While the pressure changes from 0.1 MPa to 0.3 MPa with equal interval, the solubility coefficient also increases linearly. The variation of the solubility coefficient with temperature under different pressure conditions all decreases exponentially. An equation is given to calculate the solubility coefficient of methyl iodide under different pressure and temperature conditions. (authors)

  11. Gravimetric determination of cadmium with o-phenanthroline and iodide

    International Nuclear Information System (INIS)

    Yoshida, Hitoshi; Mizuno, Kazunori; Taga, Mitsuhiko; Hikime, Seiichiro

    1976-01-01

    Cadmium forms insoluble mixed ligand complex with o-phenanthroline and iodide ions. By using the complex a new gravimetric method for the determination of cadmium was investigated. The recommended analytical procedure is as follows: Adjust pH value of a solution containing 5 to 45 mg cadmium to 4 with 3 M acetic acid-sodium acetate buffer solution. Add over threefold moles of potassium iodide to the solution and heat to just before boiling. To the solution add 0.1% ascorbic acid solution and then 0.1 M o-phenanthroline solution drop by drop in excess with stirring, and cool the mixture to room temperature. Filter the precipitates and wash first with 0.01% potassium iodide solution and then with water. Dry the precipitates at 110 0 C for two hours and weigh as Cd(o-phen) 2 I 2 (I). The gravimetric factor of the complex for cadmium is 0.1547. Chemical composition of the precipitate is variable when o-phenanthroline is added less than twofold moles to cadmium. Adding the o-phenanthroline solution 2.4-fold moles against cadmium, the ternary complex (I) precipitates quantitatively. Though a large excess of iodide ion in the solution contaminated the precipitate, the contamination was avoided when precipitation was carryed out at high temperature and in the presence of ascorbic acid. By the presented procedure 5 to 45 mg of cadmium are determined with a standard deviation of 0 C. (JPN)

  12. Kinetic method for determination of iodide ion ultramicroamounts

    International Nuclear Information System (INIS)

    Barkauskas, Yu.K.; Ramanauskas, Eh.I.

    1980-01-01

    A kinetic method for iodides ultramicroamount determination from their catalytic effect on oxidation of malachite green with chloramine B in the presence of acetone at pH 5.78+-0.3 is developed. The induction period of the reaction is determined from a change in the redox potential of the system. The induction period is proportional to the iodides concentration. Determination limit of iodides is equal to 4 μg iodide per 100 l of solution. More than 10 5 -multiple amounts of K + , Na + , NH 4+ , Ba 2 + , Al 3 + , Cu 2 + , Mg 2 + , SO 4 2 - , Cl - , MoO 4 2 - , NO 3- , ClO 3- , IO 3- , IO 4- , ClO 4- , BrO 3- ; 10 5 -10 3 -multiple amounts of Cr 3 + , Fe 3 + , Sn 2 + , S 2 - , MnO 4- , NO 2- etc. do not interfere with the determination, while 10-multiple amounts of SCN, 0.2-multiple quantities of Ag + , Hg 2 2 + do

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

    NARCIS (Netherlands)

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

    2016-01-01

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

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

    NARCIS (Netherlands)

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

    2017-01-01

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

  15. Detection of apoptotic cells using propidium iodide staining

    NARCIS (Netherlands)

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

    2014-01-01

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

  16. 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.

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

    International Nuclear Information System (INIS)

    Soelberg, Nicholas Ray; Watson, Tony Leroy

    2015-01-01

    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 HNO 3 and increased NO 2 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 NO 2 , very low H 2 O 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 I 2 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.

  18. Kinetic method for determination of iodide ion ultramicroamounts. Kineticheskij sposob opredeleniya ul'tramikrokolichestv iodid-ionov

    Energy Technology Data Exchange (ETDEWEB)

    Barkauskas, Yu K; Ramanauskas, Eh I

    1980-04-03

    A kinetic method for iodides ultramicroamount determination from their catalytic effect on oxidation of malachite green with chloramine B in the presence of acetone at pH 5.78+-0.3 is developed. The induction period of the reaction is determined from a change in the redox potential of the system. The induction period is proportional to the iodides concentration. Determination limit of iodides is equal to 4 ..mu..g iodide per 100 l of solution. More than 10/sup 5/-multiple amounts of K/sup +/, Na/sup +/, NH/sub 4//sup +/, Ba/sup 2 +/, Al/sup 3 +/, Cu/sup 2 +/, Mg/sup 2 +/, SO/sub 4//sup 2 -/, Cl/sup -/, MoO/sub 4//sup 2 -/, NO/sub 3//sup -/, ClO/sub 3//sup -/, IO/sub 3//sup -/, IO/sub 4//sup -/, ClO/sub 4//sup -/, BrO/sub 3//sup -/; 10/sup 5/-10/sup 3/-multiple amounts of Cr/sup 3 +/, Fe/sup 3 +/, Sn/sup 2 +/, S/sup 2 -/, MnO/sub 4//sup -/, NO/sub 2//sup -/ etc. do not interfere with the determination, while 10-multiple amounts of SCN, 0.2-multiple quantities of Ag/sup +/, Hg/sub 2//sup 2 +/ do.

  19. TRIPLICATE SODIUM IODIDE GAMMA RAY MONITORS FOR THE SMALL COLUMN ION EXCHANGE PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    Couture, A.

    2011-09-20

    This technical report contains recommendations from the Analytical Development (AD) organization of the Savannah River National Laboratory (SRNL) for a system of triplicate Sodium Iodide (NaI) detectors to be used to monitor Cesium-137 ({sup 137}Cs) content of the Decontaminated Salt Solution (DSS) output of the Small Column Ion Exchange (SCIX) process. These detectors need to be gain stabilized with respect to temperature shifts since they will be installed on top of Tank 41 at the Savannah River Site (SRS). This will be accomplished using NaI crystals doped with the alpha-emitting isotope, Americium-241({sup 241}Am). Two energy regions of the detector output will be monitored using single-channel analyzers (SCAs), the {sup 137}Cs full-energy {gamma}-ray peak and the {sup 241}Am alpha peak. The count rate in the gamma peak region will be proportional to the {sup 137}Cs content in the DSS output. The constant rate of alpha decay in the NaI crystal will be monitored and used as feedback to adjust the high voltage supply to the detector in response to temperature variation. An analysis of theoretical {sup 137}Cs breakthrough curves was used to estimate the gamma activity expected in the DSS output during a single iteration of the process. Count rates arising from the DSS and background sources were predicted using Microshield modeling software. The current plan for shielding the detectors within an enclosure with four-inch thick steel walls should allow the detectors to operate with the sensitivity required to perform these measurements. Calibration, testing, and maintenance requirements for the detector system are outlined as well. The purpose of SCIX is to remove and concentrate high-level radioisotopes from SRS salt waste resulting in two waste streams. The concentrated high-level waste containing {sup 137}Cs will be sent to the Defense Waste Processing Facility (DWPF) for vitrification and the low-level DSS will be sent to the Saltstone Production Facility (SPF

  20. Triplicate Sodium Iodide Gamma Ray Monitors For The Small Column Ion Exchange Program

    International Nuclear Information System (INIS)

    Couture, A.

    2011-01-01

    This technical report contains recommendations from the Analytical Development (AD) organization of the Savannah River National Laboratory (SRNL) for a system of triplicate Sodium Iodide (NaI) detectors to be used to monitor Cesium-137 ( 137 Cs) content of the Decontaminated Salt Solution (DSS) output of the Small Column Ion Exchange (SCIX) process. These detectors need to be gain stabilized with respect to temperature shifts since they will be installed on top of Tank 41 at the Savannah River Site (SRS). This will be accomplished using NaI crystals doped with the alpha-emitting isotope, Americium-241( 241 Am). Two energy regions of the detector output will be monitored using single-channel analyzers (SCAs), the 137 Cs full-energy γ-ray peak and the 241 Am alpha peak. The count rate in the gamma peak region will be proportional to the 137 Cs content in the DSS output. The constant rate of alpha decay in the NaI crystal will be monitored and used as feedback to adjust the high voltage supply to the detector in response to temperature variation. An analysis of theoretical 137 Cs breakthrough curves was used to estimate the gamma activity expected in the DSS output during a single iteration of the process. Count rates arising from the DSS and background sources were predicted using Microshield modeling software. The current plan for shielding the detectors within an enclosure with four-inch thick steel walls should allow the detectors to operate with the sensitivity required to perform these measurements. Calibration, testing, and maintenance requirements for the detector system are outlined as well. The purpose of SCIX is to remove and concentrate high-level radioisotopes from SRS salt waste resulting in two waste streams. The concentrated high-level waste containing 137 Cs will be sent to the Defense Waste Processing Facility (DWPF) for vitrification and the low-level DSS will be sent to the Saltstone Production Facility (SPF) to be incorporated into grout.

  1. Transmutation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Viererbl, L., E-mail: vie@ujv.c [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Lahodova, Z. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Klupak, V. [Nuclear Research Institute Rez plc (Czech Republic); Sus, F. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Kucera, J. [Research Centre Rez Ltd. (Czech Republic); Nuclear Physics Institute, Academy of Sciences of the Czech Republic (Czech Republic); Kus, P.; Marek, M. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic)

    2011-03-11

    We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

  2. Transmutation detectors

    International Nuclear Information System (INIS)

    Viererbl, L.; Lahodova, Z.; Klupak, V.; Sus, F.; Kucera, J.; Kus, P.; Marek, M.

    2011-01-01

    We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

  3. Sodium iodide symporter: Its role in nuclear oncology

    International Nuclear Information System (INIS)

    Chung, June-Key

    2004-01-01

    Full text: Thyroid iodide uptake is basic to the clinical applications of radioiodine in diagnosis and therapy. Iodide uptake occurs across the membrane of thyroid follicular cells via an active transporter process mediated by the sodium/iodide symporter (NIS). The recent cloning of the gene encoding NIS enabled better characterization of the molecular mechanisms underlying the iodide transport, thus opening the way to clarify and expand its role in medicine. NIS contains 13 transmembrane segments, and its gene encodes a glycoprotein of 643 amino acids. Decreased NIS expression levels account for the reduced iodide uptake in thyroid carcinomas. We found that thyroid cancer patients with positive immunostaining for NIS responded to I-131 therapy better than did the patients with negative immunostaining. Thus, NIS gene can be used for radionuclide gene therapy. Targeted expression of functional NIS in cancer cells would enable these cells to concentrate iodide from plasma and would, therefore, offer the possibility of radioiodine therapy. We and others have shown that gene transfer of NIS into a variety of cell types confers increased radioiodine uptake up to several hundred-fold that of controls. There is great interest in exploring the possibility of NIS gene transfer to facilitate radioiodine therapy for non-thyroidal human cancers including hepatoma, prostate, breast, colon cancers as well as thyroid cancer. Recently, several approaches such as, targeted gene transfer, thyroid peroxidase gene co-transfection, retinoic acid treatment and Re-188 therapy instead of I-131, have been tried to improve this novel gene therapy. Imaging reporter gene is useful in non-invasively determining the location, duration and magnitude of transgene expression in living animal. Conventionally, HSV-tk and dopaminergic receptor (D2R) genes have been presented as possible imaging reporter genes. We proved that NIS could serve as an alternative imaging reporter gene. NIS has many

  4. Toxicological significance of renal Bcrp: Another potential transporter in the elimination of mercuric ions from proximal tubular cells

    Energy Technology Data Exchange (ETDEWEB)

    Bridges, Christy C., E-mail: bridges_cc@mercer.edu; Zalups, Rudolfs K.; Joshee, Lucy

    2015-06-01

    Secretion of inorganic mercury (Hg{sup 2+}) from proximal tubular cells into the tubular lumen has been shown to involve the multidrug resistance-associated protein 2 (Mrp2). Considering similarities in localization and substrate specificity between Mrp2 and the breast cancer resistance protein (Bcrp), we hypothesize that Bcrp may also play a role in the proximal tubular secretion of mercuric species. In order to test this hypothesis, the uptake of Hg{sup 2+} was examined initially using inside-out membrane vesicles containing Bcrp. The results of these studies suggest that Bcrp may be capable of transporting certain conjugates of Hg{sup 2+}. To further characterize the role of Bcrp in the handling of mercuric ions and in the induction of Hg{sup 2+}-induced nephropathy, Sprague–Dawley and Bcrp knockout (bcrp{sup −/−}) rats were exposed intravenously to a non-nephrotoxic (0.5 μmol·kg{sup −1}), a moderately nephrotoxic (1.5 μmol·kg{sup −1}) or a significantly nephrotoxic (2.0 μmol·kg{sup −1}) dose of HgCl{sub 2}. In general, the accumulation of Hg{sup 2+} was greater in organs of bcrp{sup −/−} rats than in Sprague–Dawley rats, suggesting that Bcrp may play a role in the export of Hg{sup 2+} from target cells. Within the kidney, cellular injury and necrosis was more severe in bcrp{sup −/−} rats than in controls. The pattern of necrosis, which was localized in the inner cortex and the outer stripe of the outer medulla, was significantly different from that observed in Mrp2-deficient animals. These findings suggest that Bcrp may be involved in the cellular export of select mercuric species and that its role in this export may differ from that of Mrp2. - Highlights: • Bcrp may mediate transport of mercury out of proximal tubular cells. • Hg-induced nephropathy was more severe in Bcrp knockout rats. • Bcrp and Mrp2 may differ in their ability to transport Hg.

  5. Detector Unit

    CERN Multimedia

    1960-01-01

    Original detector unit of the Instituut voor Kernfysisch Onderzoek (IKO) BOL project. This detector unit shows that silicon detectors for nuclear physics particle detection were already developed and in use in the 1960's in Amsterdam. Also the idea of putting 'strips' onto the silicon for high spatial resolution of a particle's impact on the detector were implemented in the BOL project which used 64 of these detector units. The IKO BOL project with its silicon particle detectors was designed, built and operated from 1965 to roughly 1977. Detector Unit of the BOL project: These detectors, notably the ‘checkerboard detector’, were developed during the years 1964-1968 in Amsterdam, The Netherlands, by the Natuurkundig Laboratorium of the N.V. Philips Gloeilampen Fabrieken. This was done in close collaboration with the Instituut voor Kernfysisch Onderzoek (IKO) where the read-out electronics for their use in the BOL Project was developed and produced.

  6. Detector trends

    International Nuclear Information System (INIS)

    Charpak, G.

    1986-01-01

    The author describes briefly the development of detectors for high energy physics experiments. Especially considered are semiconductor microstrip detectors, drift tubes, holographic bubble chambers, scintillating fiber optics, and calorimeters. (HSI).

  7. Behaviour of organic iodides under pwr accident conditions

    International Nuclear Information System (INIS)

    Alm, M.

    1982-01-01

    Laboratory experiments were performed to study the behaviour of radioactive methyl iodide under PWR loss-of-coolant conditions. The pressure relief equipment consisted of an autoclave for simulating the primary circuit and of an expansion vessel for simulating the conditions after a rupture in the reactor coolant system. After pressure relief, the composition of the CH 3 sup(127/131)I-containing steam-air mixture within the expansion vessel was analysed at 80 0 C over a period of 42 days. On the basis of the values measured and of data taken from the literature, both qualitative and quantitative assessments have been made as to the behaviour of radioactive methyl iodide in the event of loss-of-coolant accidents. (author)

  8. Infrared detectors

    CERN Document Server

    Rogalski, Antonio

    2010-01-01

    This second edition is fully revised and reorganized, with new chapters concerning third generation and quantum dot detectors, THz detectors, cantilever and antenna coupled detectors, and information on radiometry and IR optics materials. Part IV concerning focal plane arrays is significantly expanded. This book, resembling an encyclopedia of IR detectors, is well illustrated and contains many original references … a really comprehensive book.-F. Sizov, Institute of Semiconductor Physics, National Academy of Sciences, Kiev, Ukraine

  9. 1-(3-Iodopropyl-4-methylquinolin-1-ium Iodide

    Directory of Open Access Journals (Sweden)

    Todor Deligeorgiev

    2015-11-01

    Full Text Available A solvent-free “one-pot” synthetic approach to 1-(3-iodopropyl-4-methylquinolin-1-ium iodide is reported in the present work. The title compound is derived from N-alkylation of 4-methylquinoline with 1,3-diiodopropane proceeded at room temperature. The target quinolinium salt is obtained in a highly pure form. It’s structure was evaluated by 1H-NMR, 13C-NMR, and DEPT135 spectra.

  10. 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.

  11. Synthesis and evaluation of iodide uptake inhibitors in thyroid gland

    International Nuclear Information System (INIS)

    Lacotte, Pierre

    2012-01-01

    This work was intended to discover small organic molecules acting as iodide uptake inhibitors in thyroid cells. These compounds can indeed be derivatized into biochemical probes for further characterization of proteins involved in iodide transport mechanisms. On the long term, these inhibitors also appear as attractive drug candidates for treatment of thyroid pathologies or radioprotection against iodine isotopes. A similar strategy was adopted for both of the two inhibitor families. First, we synthesized a chemical library of around 100 analogues; we measured their IC50 against iodide uptake in FRTL-5 cells to get structure-activity relationships. Absolute configuration of stereo-genic centers was also investigated, and a preferential stereochemistry was found to be responsible for activity. From this basis, around twenty 'second-generation' analogues were synthesized by combining fragments contributing to biological activity. Biological evaluation indicated that nine were very potent inhibitors, with IC50 ≤ 6 nM and satisfying physicochemical properties required for drug candidates. Finally, one photoactivatable biotinylated probe was developed in each family and used for photoaffinity labeling. Several specifically labeled proteins are still under identification and constitute new potential therapeutic targets. (author)

  12. The sodium iodide symporter: its implications for imaging and therapy

    International Nuclear Information System (INIS)

    Spitzweg, C.

    2007-01-01

    The sodium iodide symporter (NIS) is an intrinsic plasma membrane glycoprotein that mediates the active transport of iodide in the thyroid gland and a number of extrathyroidal tissues, in particular lactating mammary gland. In addition to its key function in thyroid physiology, NIS-mediated iodide accumulation allows diagnostic thyroid scintigraphy as well as therapeutic radioiodine application in benign and malignant thyroid disease. NIS therefore represents one of the oldest targets for molecular imaging and therapy. Based on the effective administration of radioiodine that has been used for over 60 years in the management of follicular cell-derived thyroid cancer, cloning and characterization of the NIS gene has paved the way for the development of a novel cytoreductive gene therapy strategy based on targeted NIS expression in thyroidal and nonthyroidal cancer cells followed by therapeutic application of 131 I or alternative radionuclides, including 188 Re and 211 At. In addition, the possibility of direct and non-invasive imaging of functional NIS expression by 123 I- and 99m Tc-scintigraphy or 124 I-PET-imaging allows the application of NIS as a novel reporter gene. In conclusion, the dual role of NIS as diagnostic and therapeutic gene and the detection of extra-thyroidal endogenous NIS expression in breast cancer open promising perspectives in nuclear medicine and molecular oncology for diagnostic and therapeutic application of NIS outside the thyroid gland. (orig.)

  13. Waste-water assay with continuous algal cultures: the effect of mercuric acetate on the growth of some marine dinoflagellates

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, H.

    1976-01-01

    The effect of mercuric acetate was studied in culture experiments with the dinoflagellates Scrippsiella faeroense (Paulsen) Balech et Soares, Prorocentrum micans Ehrenberg and Gymnodinium splendens Lebour. Impairment of growth rates, in vivo chlorophyll fluorescence, maximum cell densities and morphological changes served as criteria for assessing sublethal influences. Tests were made using the batch- and continuous-culture techniques. Addition of Hg at concentrations of 0.001 mg.1/sup -1/ and higher resulted in reduction of relative growth rates. In a few cases populations recovered from the initial decline and showed new growth. Cell counts corresponded very closely to in vivo chlorophyll fluorescence measurements. Morphological variations were observed in S. faeroense, which responded (even in sublethal concentrations) by bursting its thecae, releasing naked motile cells and forming vegetative resting stages. The problems of optimal algal-bioassay methods are discussed also, in the light of results obtained by other authors.

  14. Structure/Function Analysis of Protein-Protein Interactions and Role of Dynamic Motions in Mercuric Ion Reductase

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Susan M.

    2005-05-18

    This report summarizes the activities and findings of our structure/function studies of the bacterial detoxification enzyme mercuric ion reductase. The objectives of the work were to obtain crystal structure information for the catalytic core of this enzyme, use the information to investigate the importance of specific parts of the enzyme to its function, and investigate the role of one domain of the enzyme in its function within cells. We describe the accomplishments towards these goals including many structures of the wild type and mutant forms of the enzyme that highlight its interactions with its Hg(II) substrate, elucidation of the role of the N-terminal domain in vitro and in vivo, and elucidation of the roles of at two conserved residues in the core in the mechanism of catalysis.

  15. Enhanced iodide sequestration by 3-biphenyl-5,6-dihydroimidazo 2,1-b thiazole in sodium/iodide sym-porter (NIS)-expressing cells

    International Nuclear Information System (INIS)

    Lecat-Guillet, N.; Ambroise, Y.

    2008-01-01

    The ability of the sodium/iodide sym-porter (NIS) to take up iodide has long provided the basis for cyto-reductive gene therapy and cancer treatment with radio-iodide. One of the major limitations of this approach is that radio-iodide retention in NIS-expressing cells is not sufficient for their destruction. We identified and characterized a small organic molecule capable of increasing iodide retention in HEK293 cells permanently transfected with human NIS cDNA (hNIS-HEK293) and in the rat thyroid-derived cell line FRTL-5. In the presence of 3-biphenyl-4'-yl-5,6-dihydroimidazo[2,1-b)thiazole (ISA1), the transmembrane iodide concentration gradient was increased up to 4.5-fold. Our experiments indicate that the imidazo-thiazole derivative acts either by inhibiting anion efflux mechanisms, or by promoting the relocation of iodide into subcellular compartments. This new compound is not only an attractive chemical tool to investigate the mechanisms of iodide flux at the cellular level, but also opens promising perspectives in the treatment of cancer after NIS gene transfer. (authors)

  16. Behavior of radioactive organic iodide in an atmosphere of High Temperature Gas-cooled Reactor

    International Nuclear Information System (INIS)

    Saeki, Masakatsu; Nakashima, Mikio; Sagawa, Chiaki; Masaki, Nobuyuki; Hirabayashi, Takakuni; Aratono, Yasuyuki

    1990-06-01

    Formation and decomposition behavior of radioactive organic iodide have been studied in an atmosphere of High Temperature Gas-cooled Reactor (High Temperature Engineering Test Reactor, HTTR). Na 125 I was chosen for radioactive iodine source instead of CsI diffusing from coated fuel particles. Na 125 I adsorbed on graphite was heated in pure He and He containing O 2 or H 2 O atmosphere. The results obtained are as follows. It was proved that organic iodide was formed with organic radicals released from graphite even in He atmosphere. Thus, the interchange rate of inorganic iodide with organic iodide was remarkably decreased with prolonged preheat-treatment period at 1000degC. Organic iodide formed was easily decomposed by its recirculation into hot reaction tube kept at 900degC. When organic iodide was passed through powdered graphite bed, more than 70% was decomposed at 90degC. Oxygen and water vapour intermixed in He suppressed the interchange rate of inorganic iodide with organic iodide. These results suggest that organic iodide rarely exists in the pressure vessel under normal operating condition of HTTR, and, under hypothetical accident condition of HTTR, organic iodide fraction never exceeds the value used for a safety assessment of light water reactor. (author)

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

    Science.gov (United States)

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

    2013-01-02

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

  18. Electrochemistry of silver iodide the capacity of the double layer at the silver iodide-water interface

    NARCIS (Netherlands)

    Lyklema, J.; Overbeek, J.Th.G.

    1961-01-01

    A method is described for obtaining differential double layer capacities on silver iodide. Especially the influence of the nature and concentration of indifferent electrolytes was investigated, viz., the nitrates of Li·, K·, Rb·, NH4·, H·, Tl·, Mg··, Ba··, Co··, Cd··, Pb··, La···, Th····, the

  19. Dosage du mercure dans le gaz naturel par absorption atomique sans flammes Mercury Titration in Natural Gas by Flameless Atomic Absorption

    Directory of Open Access Journals (Sweden)

    La Villa F.

    2006-11-01

    Full Text Available Cet article présente la méthode mise au point par l'Institut Français du Pétrole pour déterminer par absorption atomique sans flamme, les traces de mercure métallique contenu dans un gaz naturel. La méthode d'analyse nécessite une extraction du mercure soit sous forme d'ion mercurique en faisant passer le gaz dans une solution oxydante, soit sous forme d'amalgame avec de l'or ou de l'argent. Le premier mode opératoire s'applique aux échantillons dont la concentration en mercure est supérieure à I ttg/Nm3, le second pour des concentrations inférieures à 5 pg/Nm3. Les seuils de détection sont respectivement 10 ng (en solution et 0,3 ng (en amalgame. La répétabilité pour 100 ng de mercure (en amalgame est de ± 7% pour une probabilité de.95 %. En conclusion, dans un échantillon de gaz naturel, compte tenu du volume des prélèvements effectués, il est possible de détecter des concentrations de l'ordre du nanogramme de mercure par mètre cube de gaz. This article describes the method developed by IFP using flameless atomic absorption to determine metallic mercury traces in a natural gas. The analyst method requires a mercury extraction either in the form of mercuric ions by making the gas pass through an oxidizing solution or in the form of an amalgam with gold or silver. The former operating method applies ta samples having a mercury concentration greater than I !ag/Nm3, and the latter for concentrations smaller than 5 (-Lg/Nm3. Detection thresholds are respectively 10 ng (in solution and 0.3 ng (in amalgam. The repeatability for 100 ng of mercury (in amalgam is ± 7 % with a probability of 95%. To conclude, in a sample of natural gas, considering the volume of the samples taken, it is possible ta detect concentrations in the vicinity of one nanogrom of mercury per cubic meter of gas.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-10-15

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

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

    International Nuclear Information System (INIS)

    Adamic, M.L.; Lister, T.E.; Dufek, E.J.; Jenson, D.D.; Olson, J.E.; Vockenhuber, C.; Watrous, M.G.

    2015-01-01

    This paper presents an evaluation of an alternate method for preparing environmental samples for "1"2"9I analysis by accelerator mass spectrometry (AMS) at Idaho National Laboratory. The optimal sample preparation method is characterized by ease of preparation, capability of processing very small quantities of iodide, and ease of loading into a cathode. Electrodeposition of iodide on a silver wire was evaluated using these criteria. This study indicates that the electrochemically-formed silver iodide deposits produce ion currents similar to those from precipitated silver iodide for the same sample mass. Precipitated silver iodide samples are usually mixed with niobium or silver powder prior to loading in a cathode. Using electrodeposition, the silver is already mixed with the sample and can simply be picked up with tweezers, placed in the sample die, and pressed into a cathode. The major advantage of this method is that the silver wire/electrodeposited silver iodide is much easier to load into a cathode.

  2. Real-Time Remediation Utilizing The Backpack Sodium Iodide System And The U.S. EPA Triad Approach

    International Nuclear Information System (INIS)

    John R. Giles; Michael V. Carpenter; Lyle G. Roybal; C. P. Oertel; J. J. Jacobson; D. L. Eaton; G. L. Schwendiman

    2006-01-01

    Real-time characterization during remediation activities is being accomplished at the Idaho National Laboratory (INL) with the use of the backpack sodium iodide system (BaSIS). The BaSIS is comprised of a 3-in. by 5-in. sodium iodide (NaI) detector, differential corrected global positioning system (GPS), and portable computer, integrated into a lightweight backpack deployment platform. The system is operated with specialized software that allows the operator and/or remediation field manager to view data as they are collected. Upon completion of planned excavation stages, the area is surveyed for residual radiological contamination. After data collection is complete, data is available to the remediation field manager as a contour map showing the area(s) that require further excavation. The use of real-time measurement systems, rapid turn-around time of data, and dynamic work strategy support the U.S. Environmental Protection Agency's (EPA) Triad approach. Decisions are made in real-time as to the need for further remediation. This paper describes the BaSIS system calibration, testing and use, and outlines negotiations with the appropriate CERCLA regulatory agencies (U.S. Environmental Protection Agency, Idaho Department of Environmental Quality, and U.S. Department of Energy Idaho Operations Office) to allow the use of real-time instrumentation during the remediation process, and for confirmation surveys. By using the BaSIS in such a manner, the INL seeks to demonstrate compliance with remediation objectives

  3. Discovery of aryl-tri-fluoroborates as potent sodium/iodide sym-porter (NIS) inhibitors

    International Nuclear Information System (INIS)

    Lecat-Guillet, N.; Ambroise, Y.

    2008-01-01

    The structure-based design of sodium/iodide sym-porter (NIS) inhibitors identified new active compounds. The organo-tri-fluoroborate shown was found to inhibit iodide uptake with an IC50 value of 0.4 μM on rat-derived thyroid cells. The biological activity is rationalized by the presence of the BF3 - ion as a minimal binding motif for substrate recognition at the iodide binding site. (authors)

  4. Discovery of aryl-tri-fluoroborates as potent sodium/iodide sym-porter (NIS) inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lecat-Guillet, N.; Ambroise, Y. [CEA, DSV, Dept Bioorgan Chem and Isotop Labelling, Inst Biol and Technol, iBiTecS, F-91191 Gif Sur Yvette (France)

    2008-07-01

    The structure-based design of sodium/iodide sym-porter (NIS) inhibitors identified new active compounds. The organo-tri-fluoroborate shown was found to inhibit iodide uptake with an IC50 value of 0.4 {mu}M on rat-derived thyroid cells. The biological activity is rationalized by the presence of the BF3{sup -} ion as a minimal binding motif for substrate recognition at the iodide binding site. (authors)

  5. Detector for deep well logging

    International Nuclear Information System (INIS)

    1976-01-01

    A substantial improvement in the useful life and efficiency of a deep-well scintillation detector is achieved by a unique construction wherein the steel cylinder enclosing the sodium iodide scintillation crystal is provided with a tapered recess to receive a glass window which has a high transmittance at the critical wavelength and, for glass, a high coefficient of thermal expansion. A special high-temperature epoxy adhesive composition is employed to form a relatively thick sealing annulus which keeps the glass window in the tapered recess and compensates for the differences in coefficients of expansion between the container and glass so as to maintain a hermetic seal as the unit is subjected to a wide range of temperature

  6. Distribution of mercury in the eggs of the false melon beetle, Atrachya menetriesi Faldermann (coleoptera: chrysomeridae), treated with mercuric chloride for breaking diapause

    Energy Technology Data Exchange (ETDEWEB)

    Ando, Y

    1971-01-01

    Mercuric chloride was effective in breaking diapause in the egg of Atrachya menetriesi. The distribution of mercury in treated eggs was examined quantitatively. To break diapause eggs were dipped in an aqueous solution of mercuric chloride (0.125mM) for 5 min. About 20 ..mu..g of mercury per 100 mg of eggs was found in the chorion and none in other parts. Only a negligible amount was found in the larvae that hatched from treated eggs. Almost all the mercury was removed when eggs were washed in a dilute solution of cysteine hydrochloride or glutathione (reduced). It seems that breaking of diapause is effected even when mercury does not penetrate the chorion.

  7. Method of removing alkyl iodides or mixtures of iodine and alkyl iodides from a gas phase and an aqueous solution phase by utilizing ion exchange resins

    International Nuclear Information System (INIS)

    Shimizu, Hiroshi; Mizuuchi, Noboru; Yokoyama, Fumio.

    1967-01-01

    Alkyl iodides and mixtures of iodine and alkyl iodides are removed from a gas phase and an aquous solution phase by using solely an anion exchange resin containing a tertiary amine or together with an anion exchange resin containing quarternary ammonium compound. The resin containing the quarternary ammonium compound is employed mainly to remove iodine, and the resin containing the tertiary amine serves mainly to remove alkyl iodides. The method can be applied to collecting a majority of the methyl iodide as well as the radioactive iodine produced in the atmosphere of a reactor in case of a fuel accident. In embodiments, it is desirable to maintain the sufficient moisture content of the anion exchange resins at a sufficient moisture level so as not to reduce the migration speed of the iodine and alkyl iodides. The iodine and alkyl iodide can be produced with high efficiency and stability independently of the relative humidity of the gas phase. In examples, a solution which consists of 20.5 mg/l of iodine and 42.2mg/l of methyl iodide flew through a column of Amberite IRA-93 alone or blended with IRA-900 at a speed of 15 /hr. respectively. The resins were able to treat 400 times their equivalent in water. (Iwakiri, K.)

  8. Autoradiolytic decomposition and reductant-free sodium sup 124 I- and sup 123 I-iodide

    Energy Technology Data Exchange (ETDEWEB)

    Sajjad, M.; Lambrecht, R.M.; Bakr, S.A. (King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia). Radionuclide and Cyclotron Operations)

    1990-01-01

    The presence of salts and metal cations in {sup 124}I- and {sup 123}I-sodium iodide solutions separated from {sup 124}Te targets promots autoradiolytic decomposition of iodide to several different iodine species dependent upon the chemical environment. The stabilization of the radioiodine as iodide by removal of trace salts and trace metal cations and in the absence of reducing agents is described. The high specific activity {sup 123}I- and {sup 124}I-iodide is suitable for labeling antibodies, proteins and radiopharmaceuticals. (orig.).

  9. Use of large sodium iodine detectors in precision π0 decay experiments

    International Nuclear Information System (INIS)

    Waltham, C.E.; Hasinoff, M.; Virtue, C.J.; Robertson, B.C.; Shor, A.; Chew, S.H.; Lowe, J.

    1987-01-01

    Three large sodium iodide detectors have been used to measure the π 0 electomagnetic form factor. The manner in which they were operated is described here with particular emphasis on optimizing energy resolution, measuring response functions and acceptance, and precise energy calibration. Neutron rejection by pulse shape discrimination was also investigated. (orig.)

  10. Performance of lead iodide nuclear radiation detectors with the introduction of rare earth elements

    Czech Academy of Sciences Publication Activity Database

    Hassan, M. A. S.; Matuchová, Marie; Žďánský, Karel

    2006-01-01

    Roč. 4, č. 1 (2006), s. 117-123 ISSN 1644-3608. [Conference on Solid State Physics and Materials Science /25./. Luxor, 06.03.2005-10.03.2005] R&D Projects: GA ČR(CZ) GA102/03/0379; GA ČR(CZ) GA102/04/0959 Institutional research plan: CEZ:AV0Z20670512 Keywords : dielectric losses * refractive index * semiconductor technology Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.524, year: 2005

  11. Preparation of lead iodide as input material for X-Ray detectors

    Czech Academy of Sciences Publication Activity Database

    Matuchová, Marie; Procházková, Olga; Žďánský, Karel; Zavadil, Jiří; Maixner, J.

    2005-01-01

    Roč. 480-481, - (2005), s. 477-481 ISSN 0255-5476 R&D Projects: GA ČR(CZ) GA102/03/0379; GA ČR(CZ) GA102/04/0959; GA ČR(CZ) GA102/01/1338 Institutional research plan: CEZ:AV0Z20670512 Keywords : lead compounds * purification * photoluminescence * zone melting Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.399, year: 2005

  12. Temperature dependent energy levels of methylammonium lead iodide perovskite

    Science.gov (United States)

    Foley, Benjamin J.; Marlowe, Daniel L.; Sun, Keye; Saidi, Wissam A.; Scudiero, Louis; Gupta, Mool C.; Choi, Joshua J.

    2015-06-01

    Temperature dependent energy levels of methylammonium lead iodide are investigated using a combination of ultraviolet photoemission spectroscopy and optical spectroscopy. Our results show that the valence band maximum and conduction band minimum shift down in energy by 110 meV and 77 meV as temperature increases from 28 °C to 85 °C. Density functional theory calculations using slab structures show that the decreased orbital splitting due to thermal expansion is a major contribution to the experimentally observed shift in energy levels. Our results have implications for solar cell performance under operating conditions with continued sunlight exposure and increased temperature.

  13. Temperature dependent energy levels of methylammonium lead iodide perovskite

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Benjamin J.; Marlowe, Daniel L.; Choi, Joshua J., E-mail: jjc6z@virginia.edu, E-mail: mgupta@virginia.edu, E-mail: scudiero@wsu.edu [Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Sun, Keye; Gupta, Mool C., E-mail: jjc6z@virginia.edu, E-mail: mgupta@virginia.edu, E-mail: scudiero@wsu.edu [Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Saidi, Wissam A. [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States); Scudiero, Louis, E-mail: jjc6z@virginia.edu, E-mail: mgupta@virginia.edu, E-mail: scudiero@wsu.edu [Chemistry Department and Materials Science and Engineering Program, Washington State University, Pullman, Washington 99164 (United States)

    2015-06-15

    Temperature dependent energy levels of methylammonium lead iodide are investigated using a combination of ultraviolet photoemission spectroscopy and optical spectroscopy. Our results show that the valence band maximum and conduction band minimum shift down in energy by 110 meV and 77 meV as temperature increases from 28 °C to 85 °C. Density functional theory calculations using slab structures show that the decreased orbital splitting due to thermal expansion is a major contribution to the experimentally observed shift in energy levels. Our results have implications for solar cell performance under operating conditions with continued sunlight exposure and increased temperature.

  14. 1-(Ferrocen-1-ylmethyl-3-methylimidazol-3-ium iodide

    Directory of Open Access Journals (Sweden)

    Vincent O. Nyamori

    2012-12-01

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

  15. Syntheses with isotopically labelled carbon. Methyl iodide, formaldehyde and cyanide

    International Nuclear Information System (INIS)

    Finn, R.D.; Boothe, T.E.; Vora, M.M.; Hildner, J.C.; Emran, A.M.; Kothari, P.J.

    1984-01-01

    Many of the uniquely labelled synthetic precursors currently employed in the design of sophisticated radiolabelled compounds have their origins in the field of hot atom chemistry. Particularly, the development during the past few years of automated, on-line synthetic procedures which combine the nuclear reaction, hot atom and classical chemistry, and rapid purification methods has allowed the incorporation of useful radionuclides into suitable compounds of chemical and biochemical interest. The application of isotopically labelled methyl iodide, formaldehyde, and cyanide anion as synthetic intermediates in research involving human physiology and nuclear medicine, as well as their contributions to other scientific methodology, is reviewed. (author)

  16. Amorphous silicon pixel layers with cesium iodide converters for medical radiography

    International Nuclear Information System (INIS)

    Jing, T.; Cho, G.; Goodman, C.A.

    1993-11-01

    We describe the properties of evaporated layers of Cesium Iodide (Thallium activated) deposited on substrates that enable easy coupling to amorphous silicon pixel arrays. The CsI(Tl) layers range in thickness from 65 to 220μm. We used the two-boat evaporator system to deposit CsI(Tl) layers. This system ensures the formation of the scintillator film with homogenous thallium concentration which is essential for optimizing the scintillation light emission efficiency. The Tl concentration was kept to 0.1--0.2 mole percent for the highest light output. Temperature annealing can affect the microstructure as well as light output of the CsI(Tl) film. 200--300C temperature annealing can increase the light output by a factor of two. The amorphous silicon pixel arrays are p-i-n diodes approximately lμm thick with transparent electrodes to enable them to detect the scintillation light produced by X-rays incident on the CsI(Tl). Digital radiography requires a good spatial resolution. This is accomplished by making the detector pixel size less then 50μm. The light emission from the CsI(Tl) is collimated by techniques involving the deposition process on pattered substrates. We have measured MTF of greater than 12 line pairs per mm at the 10% level

  17. NaI Detector Network at Aragats

    International Nuclear Information System (INIS)

    Avakyan, Karen; Arakelyan, Karen; Chilingarian, Ashot; Daryan, Ara; Kozliner, Lev; Mailyan, Bagrat; Hovsepyan, Gagik; Pokhsraryan, David; Sargsyan, David

    2013-01-01

    The Aragats Space Environmental Center (ASEC) provides monitoring of different species of secondary cosmic rays and consists of two high altitude research stations on Mt. Aragats in Armenia. Along with solar modulation effects, ASEC detectors register several coherent enhancements associated with thunderstorm activity. The experimental techniques used allowed for the first time to simultaneously measure fluxes of the electrons, muons, gamma rays, and neutrons correlated with thunderstorm activity. Ground-based observations by a complex of surface particle detectors, measuring in systematically and repeatable fashion, gamma quanta, electrons, muons and neutrons from atmospheric sources are necessary for proving the theory of particle acceleration and multiplication during thunderstorms. Energy spectra and correlations between fluxes of different particles, measured on Earth's surface address the important issues of research of the solar modulation effects and the atmospheric high-energy phenomena. In May 26 2011, launched 5 NaI(Tl) (thallium-doped sodium iodide) scintillation detectors and 1 plastic one in the new ASEC laboratory on Aragats to detect low energy gamma rays from the thunderclouds and short particle bursts. Including NaI(Tl) detectors in ASEC detectors system is of great importance for investigation thunderstorm phenomena because NaI(Tl) detectors have high efficiency of gamma ray detecting in comparison with plastic ones.

  18. Selective gettering of hydrogen in high pressure metal iodide lamps

    International Nuclear Information System (INIS)

    Kuus, G.

    1976-01-01

    One of the main problems in the manufacture of high pressure gas discharge lamps is the elimination of gaseous impurities from their arc tubes. Long degassing processes of all the lamp components are necessary in order to produce lamps with a low ignition voltage and good maintenance of the radiation properties. The investigation described deals with a selective getter place in the arc tube which can replace the long degassing process. The getter consists of a piece of yttrium encapsulated in thin tantalum foil. By this way it is possible to use the gettering action of tantalum and yttrium without having reaction between the metal iodide of the arc tube and yttrium. Yttrium is used because this metal can adsorb a large quantity of hydrogen even at a temperature of 1000 0 C. Hydrogen forms the main gaseous impurity in the high pressure metal iodide lamp. For this reason the adsorption properties like adsorption rate and capacity of the tantalum--yttrium getter for hydrogen are examined, and the results obtained from lamp experiments are given

  19. Organic iodide capture using a zeolite dry filtration

    International Nuclear Information System (INIS)

    Park, Sanggil; Sung, Joonyoung; Kim, Gi-ppeum; Lee, Jaeyoung

    2017-01-01

    An organic iodide, especially, methyl iodide (CH 3 I) would generated non-negligibly from a severe accident in a nuclear power plant. This CH 3 I will be dangerous for human when it was inhaled, it is highly toxic and causes a serious nerve disorder. Even it is a major contributor to a thyroid cancer. In order to prevent its environmental release, it is required to decontaminate using a filtration system. For the removal of CH 3 I from the release gases, wet-type is not ideal due to a high re-volatile characteristics of CH 3 I. It may become volatile after dissolving in a pool and forms CH 3 I again at the surface of water pool. Therefore, a dry-filtration should be installed to remove the CH 3 I. In this study, we preliminary investigate the characteristics of zeolite filtration methods for the removal of CH 3 I. We used both silver ion exchanged ZSM-5-zeolite (Ag+-ZSM-5) to study the effect of silver ion for the removal of iodine from CH 3 I. In summary, the CH 3 I capture tests using a silver ion exchanged zeolite was conducted in the coupled TGAGC test set-up. The mass change of the sample and concentration of CH 3 I were measured. The samples were investigated by the SEM/EDS to see its surface characteristics.

  20. Interruption with the Migration of Iodide by GR(CT)

    International Nuclear Information System (INIS)

    Min, J. H.; Lee, J. K.; Jeong, J. T.

    2012-01-01

    The purpose of this study is to understand the influence of green rust on the migration of iodide. GR(CT) would be major corrosion product of iron near the seawater or saline layer in underground. The GR(CT) may play an important role in the retardation of the iodide migration in a deep geological environment due to it's anionic exchange reaction. In underground radioactive waste repository, the corrosion of iron canisters would be proceed as follows; Fe(II) and/or Fe(III) dissolved from iron containers → Fe(II)(OH) 2 and/or Fe(III)(OH) 3 → Green rust → Lepidocrocite or Magnetite → Goetite etc. Generally, the green rust has known to exist in environments close to the Fe(Π)/Fe(ΠΙ) transition zone or between the oxidized layer and reduced layer in the underground. As anion exchanger and strong reducer, the green rusts can affect the migration of anions, reactions involving green rusts were poorly studied in relation to the safety assessment of radioactive waste repository

  1. Nuclear detonation, thyroid cancer and potassium iodide prophylaxis

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2011-01-01

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

  2. Panel on accelerators and detectors in the 1950s

    International Nuclear Information System (INIS)

    Jones, L.W.; Amaldi, U.; Hofstadter, R.; Kerst, D.W.; Wilson, R.R.

    1989-01-01

    The article takes the form of a panel of famous particle physics scientists discussing accelerator design and detectors used in the 1950s. The discussion ranges over accelerator energy capacities, the invention of alternating-gradient focusing, and colliding beam machines, beam stacking and the application of digital computers to accelerator calculations. The development of particle beams using strong-focusing lenses and electrostatic separators rounded off the decade. Detectors moved from bubble chambers, the use of plastic and inorganic scintillators, to hadron calorimeters, Cherenkov counters and finally spark chambers. Various discoveries made using sodium iodide scintillation counters are noted. (UK)

  3. Development of w/o microemulsion for transdermal delivery of iodide ions.

    Science.gov (United States)

    Lou, Hao; Qiu, Ni; Crill, Catherine; Helms, Richard; Almoazen, Hassan

    2013-03-01

    The objective of this study was to develop a water-in-oil (w/o) microemulsion which can be utilized as a transdermal delivery for iodide ions. Several w/o microemulsion formulations were prepared utilizing Span 20, ethanol, Capryol 90®, and water. The selected formulations had 5%, 10%, 15%, 20%, and a maximum of 23% w/w water content. Potassium iodide (KI) was incorporated in all formulations at 5% w/v. Physicochemical characterizations were conducted to evaluate the structure and stability. These studies included: mean droplet size, pH, viscosity, conductivity, and chemical stability tests. In vitro human skin permeation studies were conducted to evaluate the diffusion of the iodide ion through human skin. The w/o microemulsion formulations were stable and compatible with iodide ions with water content ranging from 5% to 23% w/w. The addition of KI influenced the physicochemical properties of microemulsion as compared to blank microemulsion formulations. In vitro human skin permeation studies indicated that selected formulations improved iodide ion diffusion significantly as compared to control (KI solution; P valuemicroemulsion. Span 20, ethanol and Capryol 90 protected the iodide ions against oxidation and formed a stable microemulsion. It is worth to note that according to Hofmeister series, iodide ions tend to lower the interfacial tension between water and oil and consequently enhance overall stability. This work illustrates that microemulsion system can be utilized as a vehicle for the transdermal administration of iodide.

  4. Radiolytic formation of organic iodides from organic compounds released from ripolin paint

    International Nuclear Information System (INIS)

    Attia, S.; Evans, G.J.

    2002-01-01

    The impact of a serious nuclear reactor accident is governed to a large extent by the possible release of airborne organic iodides to the environment. This research examines the identification and behavior of organic iodides formed in the containment due to the release of organic compounds from Ripolin paint, into the aqueous phase, following a nuclear reactor accident. A bench scale apparatus installed in the irradiation chamber of a Gammacell was used to analyze the formation of organic iodides. Iodo-organics, transferred to the gas phase above irradiated aqueous samples, were analyzed using a Thermal Desorption method coupled with gas chromatography and mass spectrometry. Detailed studies of the identity of the organic compounds released and the organic iodides formed were conducted. The effects of parameters such as irradiation dose were also examined. All the organic iodides formed, under radiolytic conditions, were identified as iodo-alkanes. The organic compounds that were released from the Ripolin paint, such as methyl isobutyl ketone, were found to decompose, by a series of reactions, to produce the organic iodides. The precursor organic compounds and the organic iodides formed were observed to consist of the same alkyl group. These results indicate that organic compounds released from surface paints directly influence the formation of radiolytic organic iodide. (author)

  5. Structural templating in a nonplanar phthalocyanine using single crystal copper iodide

    OpenAIRE

    Rochford, L. A. (Luke A.); Ramadan, Alexandra J.; Keeble, Dean S.; Ryan, Mary P.; Heutz, Sandrine; Jones, T. S. (Tim S.)

    2015-01-01

    Solution-grown copper iodide crystals are used as substrates for the templated growth of the nonplanar vanadyl phthalocyanine using organic molecular beam deposition. Structural characterization reveals a single molecular orientation produced by the (111) Miller plane of the copper iodide crystals. These fundamental measurements show the importance of morphology and structure in templating interactions for organic electronics applications.

  6. A model for additive transport in metal halide lamps containing mercury and dysprosium tri-iodide

    NARCIS (Netherlands)

    Beks, M.L.; Haverlag, M.; Mullen, van der J.J.A.M.

    2008-01-01

    The distribution of additives in a metal halide lamp is examined through numerical modelling. A model for a lamp containing sodium iodide additives has been modified to study a discharge containing dysprosium tri-iodide salts. To study the complex chemistry the method of Gibbs minimization is used

  7. Extraction method for the determination of inorganic iodides in Rose Bengal labelled with 131I

    International Nuclear Information System (INIS)

    Lengyel, J.; Krtil, J.; Vecernik, J.

    1982-01-01

    An extraction method for the determination of inorganic iodides in Rose Bengal preparations labelled with 131 I is described. The method is based on the quantitative extraction of Rose Bengal into chloroform from acidic medium while the inorganic iodides remain in the aqueous phase. The method is simple, rapid, and reproducible. (author)

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

    Science.gov (United States)

    Javet, P.

    1970-01-01

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

  9. Cryogenic detectors

    International Nuclear Information System (INIS)

    Zehnder, A.

    1987-01-01

    Presently the development of new large scale detector systems, used in very high energy physics experiments, is very active. In the low energy range, the introduction of charge coupled devices allows improved spacial and energy resolution. In the keV region, high resolution can only be achieved via the well established diffraction spectrometers with the well-known disadvantage of a small throughput. There exist no efficient detectors for non-ionizing radiation such as coherent nuclear scattering of weakly interacting particles. The development of high resolution solid state detectors in the keV-region with the possibility of nuclear recoil detection is therefore highly desired. Such detectors applied in astro and particle physics would thus allow one to obtain new information not achievable otherwise. Three types of cryogenic detectors exist: Calorimeters/Bolometers. This type is sensitive to the produced excess phonons and measures the deposited energy by detecting the heat pulses. Excess charge carriers should be used to produce phonons. Tunneling junctions. This type is sensitive to excess charge produced by the Cooper pair breakup. Excess phonons should be used to break up Cooper pairs. Superheated superconducting granules (SSG). An SSG detector consists of granules, the metastability of which is disturbed by radiation. The Meissner effect then causes a change in the field distribution of the applied external field, which can be detected. The present paper discusses the basic principle of calorimetric and tunneling junction detectors and some of their applications. 26 refs., 7 figs., 1 tab

  10. Detectors - Electronics

    International Nuclear Information System (INIS)

    Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J.

    1998-01-01

    The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X → e - converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the 3 He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

  11. Hydrogen detector

    International Nuclear Information System (INIS)

    Kumagaya, Hiromichi; Yoshida, Kazuo; Sanada, Kazuo; Chigira, Sadao.

    1994-01-01

    The present invention concerns a hydrogen detector for detecting water-sodium reaction. The hydrogen detector comprises a sensor portion having coiled optical fibers and detects hydrogen on the basis of the increase of light transmission loss upon hydrogen absorption. In the hydrogen detector, optical fibers are wound around and welded to the outer circumference of a quartz rod, as well as the thickness of the clad layer of the optical fiber is reduced by etching. With such procedures, size of the hydrogen detecting sensor portion can be decreased easily. Further, since it can be used at high temperature, diffusion rate is improved to shorten the detection time. (N.H.)

  12. Iodine K-edge EXAFS analysis of iodide ion-cyclodextrin inclusion complexes in aqueous solution

    International Nuclear Information System (INIS)

    Kaneko, T; Ueda, M; Nagamatsu, S; Konishi, T; Fujikawa, T; Mizumaki, M

    2009-01-01

    We study the structure of inclusion complexes of α-, β-, γ-cyclodextrin with mono-iodide ion in aqueous solution by means of iodine K-edge EXAFS spectroscopy. The analysis is based on the assumption that two kinds of iodide ions exist in KI-cyclodextrin aqueous solution i.e. hydrated mono-iodide ions and one-one mono-iodide-cyclodextrin inclusion complexes. In KI-α-cyclodextrin system, iodine K-edge EXAFS analyse show that the average coordination number of the oxygen atoms in water molecules in the first hydration shell decreases as the fraction of included ions increases. This result suggests that dehydration process accompanies the formation of the inclusion complex. This is not found in the case of β-cyclodextrin, indicating that in this case the iodide ions are included together with the whole first hydration shell.

  13. Determination of nanogram amounts of iodide by electrochemical isotope dilution analysis

    International Nuclear Information System (INIS)

    Gabrielsson, A.-B.; Beronius, P.

    1976-01-01

    A known quantity of iodide in ethanol as solvent was labelled with 131 I-and subsequently diluted with a predetermined amount of inactive iodide. Specific activities before and after the isotope dilution were established by anodically depositing small fractions of the halide in each sample on rotating silver micro electrodes and determining the activities of the electrodeposits. The lowest concentration of iodide used in any analysis was 1.10 -5 M. Further deposition studies revealed that iodide can be deposited with 1 100% current efficiency on the rotating silver micro electrode for concentration down to 2.4.10 -6 M. Electrodeposition studies for still lower concentrations have not yet been undertaken. These results suggest that amounts of iodide ion down to about 10 ng, and possibly still smaller quantitites, might be determined with the method developed. Amounts from 42 ng to 1 μg can be determined with an error of 2.5%. (T.G.)

  14. Evaluation of optimal silver amount for the removal of methyl iodide on silver-impregnated adsorbents

    International Nuclear Information System (INIS)

    Park, G.I.; Cho, I.H.; Kim, J.H.; Oh, W.Z.

    2001-01-01

    The adsorption characteristics of methyl iodide generated from the simulated off-gas stream on various adsorbents such as silver-impregnated zeolite (AgX), zeocarbon and activated carbon were investigated. An extensive evaluation was made on the optimal silver impregnation amount for the removal of methyl iodide at temperatures up to 300 deg. C. The degree of adsorption efficiency of methyl iodide on silver-impregnated adsorbent is strongly dependent on impregnation amount and process temperature. A quantitative comparison of adsorption efficiencies on three adsorbents in a fixed bed was investigated. The influence of temperature, methyl iodide concentration and silver impregnation amount on the adsorption efficiency is closely related to the pore characteristics of adsorbents. It shows that the effective impregnation ratio was about 10wt%, based on the degree of silver utilization for the removal of methyl iodide. The practical applicability of silver-impregnated zeolite for the removal of radioiodine generated from the DUPIC process was consequently proposed. (author)

  15. Colorimetric sensing of iodide based on triazole-acetamide functionalized gold nanoparticles

    International Nuclear Information System (INIS)

    Lee, I-Lin; Sung, Yi-Ming; Wu, Shu-Pao; Wu, Chien-Hou

    2014-01-01

    We have modified gold nanoparticles (AuNPs) with triazole acetamide to obtain a material for the sensitive and selective colorimetric determination of iodide. The functionalized AuNPs were prepared by a reductive single chemical step using a Cu(I)-catalyzed click reaction. The presence of iodide ions induces the aggregation of these AuNPs and results in a color change from wine-red to purple. The iodide-induced aggregation can be detected visually with bare eyes, but also by photometry. The detection limit is as low as 15 nM. The method displays excellent selectivity for iodide over other anions due to the selective interaction with the amido groups of the triazole. The method was applied to the determination of iodide in spiked lake waters. (author)

  16. Technical note: Could benzalkonium chloride be a suitable alternative to mercuric chloride for preservation of seawater samples?

    Science.gov (United States)

    Gloël, J.; Robinson, C.; Tilstone, G. H.; Tarran, G.; Kaiser, J.

    2015-12-01

    Instrumental equipment unsuitable or unavailable for fieldwork as well as lack of ship space can necessitate the preservation of seawater samples prior to analysis in a shore-based laboratory. Mercuric chloride (HgCl2) is routinely used for such preservation, but its handling and subsequent disposal incur environmental risks and significant expense. There is therefore a strong motivation to find less hazardous alternatives. Benzalkonium chloride (BAC) has been used previously as microbial inhibitor for freshwater samples. Here, we assess the use of BAC for marine samples prior to the measurement of oxygen-to-argon (O2 / Ar) ratios, as used for the determination of biological net community production. BAC at a concentration of 50 mg dm-3 inhibited microbial activity for at least 3 days in samples tested with chlorophyll a (Chl a) concentrations up to 1 mg m-3. BAC concentrations of 100 and 200 mg dm-3 were no more effective than 50 mg dm-3. With fewer risks to human health and the environment, and no requirement for expensive waste disposal, BAC could be a viable alternative to HgCl2 for short-term preservation of seawater samples, but is not a replacement for HgCl2 in the case of oxygen triple isotope analysis, which requires storage over weeks to months. In any event, further tests on a case-by-case basis should be undertaken if use of BAC was considered, since its inhibitory activity may depend on concentration and composition of the microbial community.

  17. A thermophilic bacterial origin and subsequent constraints by redox, light and salinity on the evolution of the microbial mercuric reductase.

    Science.gov (United States)

    Barkay, Tamar; Kritee, K; Boyd, Eric; Geesey, Gill

    2010-11-01

    Mercuric reductase (MerA) is central to the mercury (Hg) resistance (mer) system, catalyzing the reduction of ionic Hg to volatile Hg(0). A total of 213 merA homologues were identified in sequence databases, the majority of which belonged to microbial lineages that occupy oxic environments. merA was absent among phototrophs and in lineages that inhabit anoxic environments. Phylogenetic reconstructions of MerA indicate that (i) merA originated in a thermophilic bacterium following the divergence of the Archaea and Bacteria with a subsequent acquisition in Archaea via horizontal gene transfer (HGT), (ii) HGT of merA was rare across phylum boundaries and (iii) MerA from marine bacteria formed distinct and strongly supported lineages. Collectively, these observations suggest that a combination of redox, light and salinity conditions constrain MerA to microbial lineages that occupy environments where the most oxidized and toxic form of Hg, Hg(II), predominates. Further, the taxon-specific distribution of MerA with and without a 70 amino acid N-terminal extension may reflect intracellular levels of thiols. In conclusion, MerA likely evolved following the widespread oxygenation of the biosphere in a thermal environment and its subsequent evolution has been modulated by the interactions of Hg with the intra- and extracellular environment of the organism. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.

  18. Mercuric ion reduction and resistance in transgenic Arabidopsis thaliana plants expressing a modified bacterial merA gene.

    Science.gov (United States)

    Rugh, C L; Wilde, H D; Stack, N M; Thompson, D M; Summers, A O; Meagher, R B

    1996-01-01

    With global heavy metal contamination increasing, plants that can process heavy metals might provide efficient and ecologically sound approaches to sequestration and removal. Mercuric ion reductase, MerA, converts toxic Hg2+ to the less toxic, relatively inert metallic mercury (Hg0) The bacterial merA sequence is rich in CpG dinucleotides and has a highly skewed codon usage, both of which are particularly unfavorable to efficient expression in plants. We constructed a mutagenized merA sequence, merApe9, modifying the flanking region and 9% of the coding region and placing this sequence under control of plant regulatory elements. Transgenic Arabidopsis thaliana seeds expressing merApe9 germinated, and these seedlings grew, flowered, and set seed on medium containing HgCl2 concentrations of 25-100 microM (5-20 ppm), levels toxic to several controls. Transgenic merApe9 seedlings evolved considerable amounts of Hg0 relative to control plants. The rate of mercury evolution and the level of resistance were proportional to the steady-state mRNA level, confirming that resistance was due to expression of the MerApe9 enzyme. Plants and bacteria expressing merApe9 were also resistant to toxic levels of Au3+. These and other data suggest that there are potentially viable molecular genetic approaches to the phytoremediation of metal ion pollution. Images Fig. 2 Fig. 3 Fig. 4 PMID:8622910

  19. The Effects of Chronic Ingestion of Mercuric Chloride on Fertility and Testosterone Levels in Male Sprague Dawley Rats

    Directory of Open Access Journals (Sweden)

    John C. Heath

    2012-01-01

    Full Text Available Although male infertility is well researched, the effects of inorganic mercury on male reproduction and fertility are less well known. Studies pertaining to mercury and male fertility identified reduced concentration of testosterone in the serum of male workers, a toxic influence on fertility of organic mercury compounds within concentrations at the workplace, and increased days to pregnancy. We evaluated the effect of chronic mercuric chloride (HgCl2 exposure in male rats on reproductive endpoints. Thirty-day old male Sprague Dawley rats (n=31 were exposed to 0.0, 1.0, or 2.0 mg/kg/day of HgCl2 via gavage. After 60 days exposure, they were housed with nonexposed females for 21 days. A survivor analysis revealed the exposed animals took longer to impregnate the females and had a lower rate of impregnation. Further statistical analysis revealed a lower correlation between testicular testosterone levels and days to impregnate, and also lower sperm counts in the epididymis head and body of the exposed males. The results indicate that HgCl2 exposure had significant adverse effects on male rat reproduction endpoints including fertility at a dose that was not clinically toxic.

  20. Picomolar selective detection of mercuric ion (Hg{sup 2+}) using a functionalized single plasmonic gold nanoparticle

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hyeon Don; Choi, Inhee; Yang, Young In; Hong, Surin; Lee, Suseung; Yi, Jongheop [School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 151-742 (Korea, Republic of); Kang, Taewook, E-mail: xinly601@snu.ac.kr, E-mail: iniini79@snu.ac.kr, E-mail: netmo00@snu.ac.kr, E-mail: pell2004@snu.ac.kr, E-mail: jazz1863@snu.ac.kr, E-mail: twkang@sogang.ac.kr, E-mail: jyi@snu.ac.kr [Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 121-742 (Korea, Republic of)

    2010-04-09

    A highly sensitive method for the selective detection and quantification of mercuric ions (Hg{sup 2+}) using single plasmonic gold nanoparticle (GNP)-based dark-field microspectroscopy (DFMS) is demonstrated. The method is based on the scattering property of a single GNP that is functionalized with thiolated molecules, which is altered when analytes bind to the functionalized GNP. The spectral resolution of the system is 0.26 nm and a linear response to Hg{sup 2+} was found in the dynamic range of 100 pM-10 {mu}M. The method permits Hg{sup 2+} to be detected at the picomolar level, which is a remarkable reduction in the detection limit, considering the currently proscribed Environmental Protection Agency regulation level (10 nM, or 2 ppb) and the detection limits of other optical methods for detecting Hg{sup 2+} (recently approx. 1-10 nM). In addition, Hg{sup 2+} can be sensitively detected in the presence of Cd{sup 2+}, Pb{sup 2+}, Cu{sup 2+}, Zn{sup 2+} and Ni{sup 2+}, which do not interfere with the analysis. Based on the findings reported herein, it is likely that single-nanoparticle-based metal ion sensing can be extended to the development of other chemo- and biosensors for the direct detection of specific targets in an intracellular environment as well as in environmental monitoring.

  1. Mercury Toxicity and Contamination of Households from the Use of Skin Creams Adulterated with Mercurous Chloride (Calomel

    Directory of Open Access Journals (Sweden)

    Lori Copan

    2015-09-01

    Full Text Available Inorganic mercury, in the form of mercurous chloride, or calomel, is intentionally added to some cosmetic products sold through informal channels in Mexico and the US for skin lightening and acne treatment. These products have led to multiple cases of mercury poisoning but few investigations have addressed the contamination of cream users’ homes. We report on several cases of mercury poisoning among three Mexican-American families in California from use of mercury-containing skin creams. Each case resulted in widespread household contamination and secondary contamination of family members. Urine mercury levels in cream users ranged from 37 to 482 µg/g creatinine and in non-users from non-detectable to 107 µg/g creatinine. Air concentrations of up to 8 µg/m3 of mercury within homes exceeded the USEPA/ATSDR health-based guidance and action level of <1.0 μg/m3. Mercury contamination of cream users’ homes presented a multi-pathway exposure environment to residents. Homes required extensive decontamination, including disposal of most household items, to achieve acceptable air levels. The acceptable air levels used were not designed to consider multi-pathway exposure scenarios. These findings support that the calomel is able to change valence form to elemental mercury and volatilize once exposed to the skin or surfaces in the indoor environment.

  2. Voltammetric behavior, biocidal effect and synthesis of some new nanomeric fused cyclic thiosemicarbazones and their mercuric(II salts

    Directory of Open Access Journals (Sweden)

    M.S.T. Makki

    2014-11-01

    Full Text Available New nanomeric 3-thioxo-5-methoxy-4,5-dihydro-6-methyl-9-unsubstituted/substituted-1,2,4-triazino[5,6-b]indoles (2a–c and 3-thioxo-5-methoxy-4,5-dihydro-6,7-dihydroxy-1,2,4-triaino[5,6]-cyclobut-6-ene (3 were prepared via reaction of thiosemicarbazide with 5-unsubstitutedand/substituted-indol-2,3-diones and/or 3,4-dihydroxycyclobutane-1,2-dione in methanol–concentrated HCl at room temperature. A series of mercury(II–ligand salts e.g. compound 4b and Hg(II complexes 5a,b and 6 of cyclic Schiff base were prepared. Structures of these compounds were established by elemental analysis and spectral measurements. The redox characteristics of selected compounds were studied for use as chelating agents for stripping voltammetric determination of mercuric(II ions in aqueous media. The compounds were also screened for their use as molluscicidal agents against Biomophalaria Alexandrina Snails responsible for Bilhariziasis.

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

    International Nuclear Information System (INIS)

    Lyckesvärd, Madeleine Nordén; Kapoor, Nirmal; Ingeson-Carlsson, Camilla; Carlsson, Therese; Karlsson, Jan-Olof; Postgård, Per; Himmelman, Jakob; Forssell-Aronsson, Eva; Hammarsten, Ola; Nilsson, Mikael

    2016-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-05-15

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

  5. Linearity and Reversibility of Iodide Adsorption on Sediments from Hanford, Washington Under Water Saturated Conditions

    International Nuclear Information System (INIS)

    Um, Wooyong; Serne, R. Jeffrey; Krupka, Kenneth M.

    2004-01-01

    A series of adsorption and desorption experiments were completed to determine the linearity of iodide adsorption, as a function of concentration, and its reversibility onto sediment for geochemical conditions germane to the proposed disposal of low-level radioactive waste by the U.S. Department of Energy's Immobilized Low Activity Waste (ILAW) program at the Hanford Site in southeastern Washington. Iodine-129 is predicted to be one of the top three long-term risk drivers based on past performance assessment conducted for the eventual disposal of the low-level portion of radioactive wastes currently stored in underground storage tanks at Hanford, because iodide exhibits little adsorption affinity to mineral surfaces resulting in high mobility in the subsurface environment. Adsorption experiments, conducted with Hanford formation sediments and groundwater spiked with dissolved 125I (as an analog tracer for 129I), indicated that iodide adsorption was very low at pH 7.5 and could be represented by a linear isotherm up to a total concentration of 100 mg/L dissolved iodide. The linearity of iodide adsorption up to concentrations of 100 mg/L validates the use of the linear Kd construct in transport models to predict the fate and transport of 129I in subsurface systems at Hanford. The results of desorption experiments indicated that up to 60% of adsorbed iodide was readily desorbed after 14 days by the same groundwater solution. Iodide adsorption was considered to be partially reversible or weakly binding on the sediments. Even though small amount of initial iodide is retarded by adsorption reactions at mineral-water interfaces, the weak adsorption affinity results in release of iodide when iodide free pore waters and ground waters contact the contaminated sediments in the vadose zone and aquifer systems

  6. DUMAND detector

    CERN Multimedia

    This object is one of the 256 other detectors of the DUMAND (Deep Underwater Muon And Neutrino Detection) experiment. The goal of the experiment was the construction of the first deep ocean high energy neutrino detector, to be placed at 4800 m depth in the Pacific Ocean off Keahole Point on the Big Island of Hawaii. A few years ago, a European conference with Cosmic experiments was organized at CERN as they were projects like DUMAND in Hawaii. Along with the conference, a temporary exhibition was organised as well. It was a collaboration of institutions from Germany, Japan, Switzerland and the U.S.A. CERN had borrowed equipment and objects from different institutes around the world, including this detector of the DUMAND experiment. Most of the equipment were sent back to the institutes, however this detector sphere was offered to a CERN member of the personnel.

  7. Detector applications

    International Nuclear Information System (INIS)

    Pehl, R.H.

    1977-10-01

    Semiconductor detectors are now applied to a very wide range of problems. The combination of relatively low cost, excellent energy resolution, and simultaneous broad energy-spectrum analysis is uniquely suited to many applications in both basic and applied physics. Alternative techniques, such as magnetic spectrometers for charged-particle spectroscopy, while offering better energy resolution, are bulky, expensive, and usually far more difficult to use. Furthermore, they do not directly provide the broad energy-spectrum measurements easily accomplished using semiconductor detectors. Scintillation detectors, which are approximately equivalent to semiconductor detectors in convenience and cost, exhibit 10 to 100 times worse energy resolution. However, their high efficiency and large potential size recommend their use in some measurements

  8. Smoke detectors

    International Nuclear Information System (INIS)

    Bryant, J.; Howes, J.H.; Smout, D.W.S.

    1979-01-01

    A smoke detector is described which provides a smoke sensing detector and an indicating device and in which a radioactive substance is used in conjunction with two ionisation chambers. The system includes an outer electrode, a collector electrode and an inner electrode which is made of or supports the radioactive substance which, in this case, is 241 Am. The invention takes advantage of the fact that smoke particles can be allowed to enter freely the inner ionisation chamber. (U.K.)

  9. Radiation detector

    International Nuclear Information System (INIS)

    Gillies, W.

    1980-01-01

    The radiation detector for measuring e.g. a neutron flux consists of a central emitter, an insulating shell arranged around it, and a tube-shaped collector enclosing both. The emitter itself is composed of a great number of stranded, spiral wires of small diameter giving a defined flexibility to the detector. For emitter material Pt, Rh, V, Co, Ce, Os or Ta may be used. (DG) [de

  10. Split detector

    International Nuclear Information System (INIS)

    Cederstrand, C.N.; Chism, H.R.

    1982-01-01

    A gas analyzer is disclosed which provides a dual channel capability for the simultaneous determination of the presence and concentration of two gases in a stream of sample gas and which has a single infrared source, a single sample cell, two infrared bandpass filters, and two infrared detectors. A separator between the filters and detectors prevents interchange of radiation between the filters. The separator is positioned by fitting it in a slot

  11. Polarographic determination of indium and thallium iodides in phosphor tablets

    International Nuclear Information System (INIS)

    Babich, G.A.; Dzhurka, G.F.; Kozhushko, G.M.; Kravtsova, K.F.; Magda, V.I.

    1984-01-01

    The technique of polarographic determination of indium and thallium iodides in phosphor tablets without preliminary separation of elements was developed. Mercury-dropping electrode was used as an indicator, and saturated calomel electrode was used as an auxiliary electrode. A recording of reduction currents was performed in the potential interval from -0.25 up to 1.15 V at potential sweep speed of 200 mV/min. Optimum conditions of sample acidic decomposition and polarography were presented. A solution of ethylene diamine (0.5 M), of ammonia (0.25 M) and of potassium chloride (0.05 M) served as a background electrolyte. The suggested technique allows one to determine component contents in tablets with a satisfactory accuracy. A period of one tablet analysis constitutes 1.5 h

  12. Direct photometric determination of fluorides in potassium chloride and iodide

    International Nuclear Information System (INIS)

    Dedkova, V.P.; Savvin, S.B.

    1985-01-01

    An attempt is made to apply the technique of determining fluorides with xylenol orange and sulfochlorophenol S as being the most sensitive in the analysis of of fiber optics. It is known that an increase of the sensitivity of the determination can be achieved on increasing the sample size of the substance to be analyzed, and the length of the absorbing layer. However, a high salt background may have a strong influence on the course of the reaction, and a supplementary of this effect is mad. Potassium chloride and iodide were selected as model compounds. A direct photometric procedure is proposed for determining fluorides in the samples, with a determination limit of 5 x 10 -6 %. Such a low determination limit is achieved by increasing the sample weight to 3 g, by increasing the length of the absorbing layer in the cell to 50 mm, and by using a highly sensitive reaction for determining fluorides with zirconium and xylenol orange

  13. Comparison of gamma densitometer detectors used in loss of coolant studies

    International Nuclear Information System (INIS)

    Shipp, R.L.

    1979-01-01

    Ionization chamber type gamma detectors are used in water-steam density measurements in loss of coolant studies at Oak Ridge National Laboratory. Ionization chambers have replaced current-mode scintillation detectors to obtain stability and freedom from magnetic field interference. However, this change results in some loss of fast transient response. Results of studies comparing the transient response of ionization chamber detectors, plastic scintillation detectors, and sodium iodide (NaI) detectors to rapid changes in gamma intensity demonstrate that plastic scintillation detectors have the fastest response and most closely reproduce the transient; ionization chambers have an initial fast response followed by a slower response, which may produce errors in fast transient measurements; and NaI scintillation detectors have a moderately fast initial response followed by an extremely slow response, which produces errors in even slow transient measurements

  14. Rapid sonochemical preparation of shape-selective lead iodide

    International Nuclear Information System (INIS)

    Huang, Baojun; He, Qin; Fa, Wenjun; Li, Pinjiang; Zhang, Yange; Zheng, Zhi

    2012-01-01

    Graphical abstract: SEM morphologies of various PbI2 products obtained with the iodine concentration of 6.7 g/L and irradiation time of 1 minute at the reaction temperatures of 35 °C (a), 25 °C (b), and 15 °C (c). Highlights: ► PbI 2 with various morphologies were rapidly formed at room temperature. ► We could well control the morphologies of PbI 2 by changing reaction conditions. ► The PbI 2 films could better resist rolling in a liquid media. -- Abstract: Lead iodide (PbI 2 ) films/crystals with various nano/micro morphologies (e.g., Nanoflake, block and microrod) were rapidly synthesized by taking advantage of a simple sonochemical method. The PbI 2 crystals with uniform nanoflake structures could be fabricated directly on lead foils with the irradiation time as short as 36 s via interfacial reaction between lead foils and elemental iodine in ethanol at ambient temperature. It was found experimentally that the morphologies of the resulting thin films/crystals could be well controlled by the adjustment of several parameters including irradiation time, reaction solvents, iodine concentration, ultrasonic power, and reaction temperature. Most importantly, the resultant PbI 2 films are stable enough to resist rolling under the drastic ultrasound irradiation in a liquid media. This method is believed to be the fastest way for in situ fabrication of morphology-controlled semiconductor films on various metal substrates for subsequent applications related to the other metal iodide or metal sulfide semiconductor films.

  15. Radiometric and dosimetric characteristics of HgI2 detectors

    International Nuclear Information System (INIS)

    Zaletin, V.M.; Krivozubov, O.V.; Torlin, M.A.; Fomin, V.I.

    1988-01-01

    The characteristics of HgI 2 detectors in x-ray and gamma detection in applications to radiometric and dosimetric monitoring and as portable instruments for such purposes was considered. Blocks with mosaic and sandwich structures were prepared and tested against each other and, for comparative purposes, against CdTe detectors for relative sensitivities at various gamma-quanta energies. Sensitivity dependencies on gamma radiation energy were plotted for the detector materials and structures as were current dependencies on the dose rate of x rays. Results indicated that the mercury iodide detectors could be used in radiometric and dosimetric measurements at gamma quantum energies up to and in excess of 1000 KeV

  16. Flat detectors and their clinical applications

    International Nuclear Information System (INIS)

    Spahn, Martin

    2005-01-01

    Diagnostic and interventional flat detector X-ray systems are penetrating the market in all application segments. First introduced in radiography and mammography, they have conquered cardiac and general angiography and are getting increasing attention in fluoroscopy. Two flat detector technologies prevail. The dominating method is based on an indirect X-ray conversion process, using cesium iodide scintillators. It offers considerable advantages in radiography, angiography and fluoroscopy. The other method employs a direct converter such as selenium which is particularly suitable for mammography. Both flat detector technologies are based on amorphous silicon active pixel matrices. Flat detectors facilitate the clinical workflow in radiographic rooms, foster improved image quality and provide the potential to reduce dose. This added value is based on their large dynamic range, their high sensitivity to X-rays and the instant availability of the image. Advanced image processing is instrumental in these improvements and expand the range of conventional diagnostic methods. In angiography and fluoroscopy the transition from image intensifiers to flat detectors is facilitated by ample advantages they offer, such as distortion-free images, excellent coarse contrast, large dynamic range and high X-ray sensitivity. These characteristics and their compatibility with strong magnetic fields are the basis for improved diagnostic methods and innovative interventional applications. (orig.)

  17. Evaluation of quaternary ammonium halides for removal of methyl iodide from flowing air streams

    International Nuclear Information System (INIS)

    Freeman, W.P.; Mohacsi, T.G.; Kovach, J.L.

    1985-01-01

    The quaternary ammonium halides of several tertiary amines were used as impregnants on activated carbon and were tested for methyl iodide penetration in accordance with test Method A, ASTM D3803, 1979, ''Standard Test Methods for Radio-iodine Testing of Nuclear Grade Gas Phase Adsorbents''. The results suggest that the primary removal mechanism for methyl iodide-131 is isotopic exchange with the quaternary ammonium halide. For example, a 5 wt% impregnation of each of the tetramethyl, tetraethyl, tetrapropyl and tetrabutyl ammonium iodides on activated carbon yielded percent penetrations of 0.47, 0.53, 0.78, and 0.08 respectively when tested according to Method A of ASTM D3803. A sample impregnated with 5% tetramethyl ammonium hydroxide gave a methyl iodide penetration of 64.87%, thus supporting the isotopic exchange mechanism for removal. It has been a generally held belief that the success of tertiary amines as impregnants for radioiodine removal is a result of their ability to complex with the methyl iodide. The results of the work indicates that the superiority of the tertiary amines similar to triethylene diamine and quinuclidine, when compared to their straight chain analogs, is a result of their ease in reacting with methyl iodide-127 to form the quaternary ammonium iodide followed by isotopic exchange

  18. Shaped detector

    International Nuclear Information System (INIS)

    Carlson, R.W.

    1981-01-01

    A radiation detector or detector array which has a non-constant spatial response, is disclosed individually and in combination with a tomographic scanner. The detector has a first dimension which is oriented parallel to the plane of the scan circle in the scanner. Along the first dimension, the detector is most responsive to radiation received along a centered segment of the dimension and less responsive to radiation received along edge segments. This non-constant spatial response can be achieved in a detector comprised of a scintillation crystal and a photoelectric transducer. The scintillation crystal in one embodiment is composed of three crystals arranged in layers, with the center crystal having the greatest light conversion efficiency. In another embodiment, the crystal is covered with a reflective substance around the center segment and a less reflective substance around the remainder. In another embodiment, an optical coupling which transmits light from adjacent the center segment with the greatest intensity couples the scintillation crystal and the photoelectric transducer. In yet another embodiment, the photoelectric transducer comprises three photodiodes, one receiving light produced adjacent the central segment and the other two receiving light produced adjacent the edge segments. The outputs of the three photodiodes are combined with a differential amplifier

  19. Parametric Study on the Organic Iodide Behavior during a Severe Accident

    International Nuclear Information System (INIS)

    Ryu, Myung Hyun; Kim, Han Chul; Kim, Do Sam

    2011-01-01

    Iodine is a major contributor to the potential health risk for the public following a severe accident from a nuclear power plant. Most of metal-iodides, the major form of iodine that enters the containment, can be readily dissolved in the sump water and result in iodide ions. These will be oxidized to form volatile I 2 through a large number of reactions such as radiolysis and hydrolysis. The organic radicals, made from organics such as paint in the sump water, react with iodine to produce organic iodides. Volatile iodine moves from the sump water to the atmosphere mainly by diffusion and natural convection, and react with surfaces and air radiolysis products (ARPs). Painted surfaces act as a sink for I 2 and as a source for organic iodides through adsorption and desorption. ARPs react with I 2 to form iodine oxides, which leads to the decrease of I 2 and organic iodides. Among the large number of iodine species, organic iodides have been extensively studied recently due to their volatility and very low retention. Qualified tools for modeling these phenomena have been developed and validated by several experiments such as EPICUR, PARIS and OECD-BIP. While mechanistic codes model a large number of reactions and species, semiempirical codes such as IODE or IMOD treat major ones. KINS developed a simple iodine model, RAIM (Radio-active iodine chemistry model), based on the IMOD methodology in order to deal with organic iodides conveniently, coupling with an integrated severe-accident analysis code. There are a number of mechanisms that affect the behavior of organic iodides. In this study, effects of pH of the aqueous phase, temperature, radiation dose rate, surface area of organic paints, initial iodine loads that are known to be important to organic iodide formation were studied analytically with RAIM, and also theoretically

  20. Parametric Study on the Organic Iodide Behavior during a Severe Accident

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Myung Hyun; Kim, Han Chul; Kim, Do Sam [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2011-10-15

    Iodine is a major contributor to the potential health risk for the public following a severe accident from a nuclear power plant. Most of metal-iodides, the major form of iodine that enters the containment, can be readily dissolved in the sump water and result in iodide ions. These will be oxidized to form volatile I{sub 2} through a large number of reactions such as radiolysis and hydrolysis. The organic radicals, made from organics such as paint in the sump water, react with iodine to produce organic iodides. Volatile iodine moves from the sump water to the atmosphere mainly by diffusion and natural convection, and react with surfaces and air radiolysis products (ARPs). Painted surfaces act as a sink for I{sub 2} and as a source for organic iodides through adsorption and desorption. ARPs react with I{sub 2} to form iodine oxides, which leads to the decrease of I{sub 2} and organic iodides. Among the large number of iodine species, organic iodides have been extensively studied recently due to their volatility and very low retention. Qualified tools for modeling these phenomena have been developed and validated by several experiments such as EPICUR, PARIS and OECD-BIP. While mechanistic codes model a large number of reactions and species, semiempirical codes such as IODE or IMOD treat major ones. KINS developed a simple iodine model, RAIM (Radio-active iodine chemistry model), based on the IMOD methodology in order to deal with organic iodides conveniently, coupling with an integrated severe-accident analysis code. There are a number of mechanisms that affect the behavior of organic iodides. In this study, effects of pH of the aqueous phase, temperature, radiation dose rate, surface area of organic paints, initial iodine loads that are known to be important to organic iodide formation were studied analytically with RAIM, and also theoretically

  1. Thyroid iodide compartments and their implication in the rat thyroid iodine organification

    International Nuclear Information System (INIS)

    Bastiani, P.; Simon, C.

    1982-01-01

    To estimate the relative participation of transported and intrathyroidally generated iodide (internal iodide) in the iodination of newly synthesized and preexisting thyroglobulin (Tg) in the rat thyroid, the specific radioactivities (SRAs) of thyroid iodide, Tg, lysosomal iodine, and plasma hormones were followed for 92 h after radioactive iodide injection in intact or hypophysectomized rats. In control rats, the SRA of Tg and lysosomal iodine reached a maximum at 12 h. However, the SRA of lysosomal iodide was always smaller than that of Tg. In contrast, the SRA of hormonal iodide attained a maximum at 48 h. Thus, newly labeled iodine is endocytosed and mixed inside the lysosomes with older previously iodinated molecules; hormone secretion is mainly due to old labeled iodine (i.e. iodine with a high SRA from 48-96 h). These results are consistent with the presence of least two Tg compartments, with different turnover rates and hormone contents. On the other hand, in hypophysectomized rats, the SRA of Tg, lysosomes, and hormones showed only one maximum, at 24 h. Furthermore, the SRAs of Tg and lysosomes were similar at each time interval. It is inferred that in such rats, the old labeled iodine compartment is strongly reduced, and that inside the lysosomes, newly labeled iodine is predominant. Since in hypophysectomized rats, the recycling of iodide is abolished, it is concluded that in normal rats: 1) transported iodide is organified mainly by direct iodination of newly synthesized Tg, independently of TSH, and 2) internal iodide is organified mainly by delayed iodination of preexisting Tg, this process being TSH dependent

  2. Solvent effect on the rate and equilibrium of reaction between 10-phenylphenoxarsine and methyl iodide

    International Nuclear Information System (INIS)

    Gavrilov, V.I.; Gumerov, N.S.; Rakhmatullin, R.R.

    1990-01-01

    Effect of solvent nature on nucleophilic capacity of three-coordinated arsenic and the equilibrium state of 10-phenylphenoxarsine (PA) reaction with methyl iodide are studied. Kinetic investigations are carried out by the conductometry at 24,35,45 deg C. It is established that quaternization of PA with methyl iodide when substituting a solvent (ketone for alcohol) increases 3-14 times with simultaneous growth of the activation energy value. When transforming from aprotic solvents to protic ones PA interaction equilibrium with methyl iodide shifts to the side of arsonic salt formation

  3. The method of determination of micro quantities of labeled iodide in carrier free Na125 solution

    International Nuclear Information System (INIS)

    Kholbaev, A.Kh.; Shilin, E.A.

    1996-01-01

    The method of determination of microquantities of labelled iodide in Na 125 carrier-free solution was elaborated. This method permits to increase the sensitivity and radiation protection of the determination of labeled iodide. It includes oxidation of iodide by iodate in diluted sulphuric acid with molar concentration 0,03-0,04 mole/l. The extraction of I 2 is made by toluene. The coloured solution is made and optical density is measured at λ=640 nm at the 10 mm optical path .(A.A.D.)

  4. Development of mercury porosimeter. Application to nuclear graphite studies (1961); Mise au point d'un porosimetre a mercure. Application a l'etude des graphites nucleaires (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Bocquet, M; Genisson, J; Sailleau, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    A mercury porosimeter, model IFP-CEA, has been developed for application to nuclear graphite studies. The apparatus is based on the capillary depression phenomenon. The relationship between the radius of a pore and the pressure at which mercury fills it is pr = -2 {sigma} cos {theta} ( {sigma} is the surface tension, {theta} the angle of contact of the mercury). After some theoretical consideration, the apparatus is described. The mercury pressure is increased step-wise from 0 to 1000 kg/cm{sup 2} thus yielding the complete distribution of pores from 92 {mu} to 75 A. Results are, then presented concerning nuclear graphites which show the evolution of the porous structure under the effect of bitumen impregnation. In general, the volume of the large pores decreases while that of the small pores increases. The structure of impregnated products appears to depend to a certain extent on that of the starting materials. It has also been possible to study other products with this porosimeter; the range of measurements possible is such that it may be used for the study of the majority of porous materials. (authors) [French] Un porosimetre a mercure modele IFP-CEA a ete mis au point en vue de son application a l'etude de graphites nucleaires. Le fonctionnement de l'appareil repose sur le phenomene de depression capillaire. On etablit la relation existant entre le rayon r d'un pore et la pression p pour laquelle le mercure peut y penetrer: pr = -2 {sigma} cos {theta} ( {sigma} tension superficielle, {theta} angle de contact du mercure). Apres quelques considerations theoriques, l'appareil utilise est decrit. Il permet de faire varier par palier la pression du mercure entre 0 et 1000 kg/cm{sup 2} et d'etablir ainsi la distribution complete des rayons de pores compris entre 92 {mu} et 75 A. Les resultats d'une etude faite sur des graphites nucleaires sont alors presentes faisant apparaitre l'evolution de la structure poreuse sous l'effet des impregnations au brai. D'une facon

  5. Mercury toxicity in the shark (Squalus acanthias) rectal gland: apical CFTR chloride channels are inhibited by mercuric chloride.

    Science.gov (United States)

    Ratner, Martha A; Decker, Sarah E; Aller, Stephen G; Weber, Gerhard; Forrest, John N

    2006-03-01

    In the shark rectal gland, basolateral membrane proteins have been suggested as targets for mercury. To examine the membrane polarity of mercury toxicity, we performed experiments in three preparations: isolated perfused rectal glands, primary monolayer cultures of rectal gland epithelial cells, and Xenopus oocytes expressing the shark cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel. In perfused rectal glands we observed: (1) a dose-dependent inhibition by mercury of forskolin/3-isobutyl-1-methylxanthine (IBMX)-stimulated chloride secretion; (2) inhibition was maximal when mercury was added before stimulation with forskolin/IBMX; (3) dithiothrietol (DTT) and glutathione (GSH) completely prevented inhibition of chloride secretion. Short-circuit current (Isc) measurements in monolayers of rectal gland epithelial cells were performed to examine the membrane polarity of this effect. Mercuric chloride inhibited Isc more potently when applied to the solution bathing the apical vs. the basolateral membrane (23 +/- 5% and 68 +/- 5% inhibition at 1 and 10 microM HgCl2 in the apical solution vs. 2 +/- 0.9% and 14 +/- 5% in the basolateral solution). This inhibition was prevented by pre-treatment with apical DTT or GSH; however, only the permeant reducing agent DTT reversed mercury inhibition when added after exposure. When the shark rectal gland CFTR channel was expressed in Xenopus oocytes and chloride conductance was measured by two-electrode voltage clamping, we found that 1 microM HgCl2 inhibited forskolin/IBMX conductance by 69.2 +/- 2.0%. We conclude that in the shark rectal gland, mercury inhibits chloride secretion by interacting with the apical membrane and that CFTR is the likely site of this action. Copyright 2006 Wiley-Liss, Inc.

  6. Miniature gamma-ray camera for tumor localization

    International Nuclear Information System (INIS)

    Lund, J.C.; Olsen, R.W.; James, R.B.; Cross, E.

    1997-08-01

    The overall goal of this LDRD project was to develop technology for a miniature gamma-ray camera for use in nuclear medicine. The camera will meet a need of the medical community for an improved means to image radio-pharmaceuticals in the body. In addition, this technology-with only slight modifications-should prove useful in applications requiring the monitoring and verification of special nuclear materials (SNMs). Utilization of the good energy resolution of mercuric iodide and cadmium zinc telluride detectors provides a means for rejecting scattered gamma-rays and improving the isotopic selectivity in gamma-ray images. The first year of this project involved fabrication and testing of a monolithic mercuric iodide and cadmium zinc telluride detector arrays and appropriate collimators/apertures. The second year of the program involved integration of the front-end detector module, pulse processing electronics, computer, software, and display

  7. BES detector

    International Nuclear Information System (INIS)

    Bai, J.Z.; Bian, Q.; Chen, G.M.; Chen, L.J.; Chen, S.N.; Chen, Y.Q.; Chen, Z.Q.; Chi, Y.K.; Cui, H.C.; Cui, X.Z.; Deng, S.S.; Deng, Y.W.; Ding, H.L.; Dong, B.Z.; Dong, X.S.; Du, X.; Du, Z.Z.; Feng, C.; Feng, Z.; Fu, Z.S.; Gao, C.S.; Gao, M.L.; Gao, S.Q.; Gao, W.X.; Gao, Y.N.; Gu, S.D.; Gu, W.X.; Guan, Y.Z.; Guo, H.F.; Guo, Y.N.; Guo, Y.Y.; Han, S.W.; Han, Y.; Hao, W.; He, J.; He, K.R.; He, M.J.; Hou, X.J.; Hu, G.Y.; Hu, J.S.; Hu, J.W.; Huang, D.Q.; Huang, Y.Z.; Jia, Q.P.; Jiang, C.H.; Ju, Q.; Lai, Y.F.; Lang, P.F.; Li, D.S.; Li, F.; Li, H.; Li Jia; Li, J.T.; Li Jin; Li, L.L.; Li, P.Q.; Li, Q.M.; Li, R.B.; Li, S.Q.; Li, W.; Li, W.G.; Li, Z.X.; Liang, G.N.; Lin, F.C.; Lin, S.Z.; Lin, W.; Liu, Q.; Liu, R.G.; Liu, W.; Liu, X.; Liu, Z.A.; Liu, Z.Y.; Lu, C.G.; Lu, W.D.; Lu, Z.Y.; Lu, J.G.; Ma, D.H.; Ma, E.C.; Ma, J.M.; Mao, H.S.; Mao, Z.P.; Meng, X.C.; Ni, H.L.; Nie, J.; Nie, Z.D.; Niu, W.P.; Pan, L.J.; Qi, N.D.; Qian, J.J.; Qu, Y.H.; Que, Y.K.; Rong, G.; Ruan, T.Z.; Shao, Y.Y.; Shen, B.W.; Shen, D.L.; Shen, J.; Sheng, H.Y.; Sheng, J.P.; Shi, H.Z.; Song, X.F.; Sun, H.S.; Tang, F.K.; Tang, S.Q.; Tian, W.H.; Wang, F.; Wang, G.Y.; Wang, J.G.; Wang, J.Y.; Wang, L.S.; Wang, L.Z.; Wang, M.; Wang, P.; Wang, P.L.; Wang, S.M.; Wang, S.Q.; Wang, T.J.; Wang, X.W.; Wang, Y.Y.; Wang, Z.H.; Wang, Z.J.; Wei, C.L.; Wei, Z.Z.; Wu, J.W.; Wu, S.H.; Wu, S.Q.; Wu, W.M.; Wu, X.D.; Wu, Z.D.; Xi, D.M.; Xia, X.M.; Xiao, J.; Xie, P.P.; Xie, X.X.; Xu, J.G.; Xu, R.S.; Xu, Z.Q.; Xuan, B.C.; Xue, S.T.; Yan, J.; Yan, S.P.; Yan, W.G.; Yang, C.Z.; Yang, C.M.; Yang, C.Y.; Yang, X.F.; Yang, X.R.; Ye, M.H.; Yu, C.H.; Yu, C.S.; Yu, Z.Q.; Zhang, B.Y.; Zhang, C.D.; Zhang, C.C.; Zhang, C.Y.; Zhang, D.H.; Zhang, G.; Zhang, H.Y.; Zhang, H.L.; Zhang, J.W.; Zhang, L.S.; Zhang, S.Q.; Zhang, Y.P.; Zhang, Y.; Zhang, Y.M.; Zhao, D.X.; Zhao, J.W.; Zhao, M.; Zhao, P.D.; Zhao, P.P.; Zhao, W.R.; Zhao, Z.G.; Zhao, Z.Q.; Zheng, J.P.; Zheng, L.S.; Zheng, M.; Zheng, W.S.; Zheng, Z.P.; Zhong, G.P.; Zhou, G.P.; Zhou, H.S.; Zhou, J.; Zhou Li; Zhou Lin; Zhou, M.; Zhou, Y.S.; Zhou, Y.H.; Zhu, G.S.; Zhu, Q.M.; Zhu, S.G.; Zhu, Y.C.; Zhu, Y.S.; Zhuang, B.A.

    1994-01-01

    The Beijing Spectrometer (BES) is a general purpose solenoidal detector at the Beijing Electron Positron Collider (BEPC). It is designed to study exclusive final states in e + e - annihilations at the center of mass energy from 3.0 to 5.6 GeV. This requires large solid angle coverage combined with good charged particle momentum resolution, good particle identification and high photon detection efficiency at low energies. In this paper we describe the construction and the performance of BES detector. (orig.)

  8. Vertex detectors

    International Nuclear Information System (INIS)

    Lueth, V.

    1992-07-01

    The purpose of a vertex detector is to measure position and angles of charged particle tracks to sufficient precision so as to be able to separate tracks originating from decay vertices from those produced at the interaction vertex. Such measurements are interesting because they permit the detection of weakly decaying particles with lifetimes down to 10 -13 s, among them the τ lepton and charm and beauty hadrons. These two lectures are intended to introduce the reader to the different techniques for the detection of secondary vertices that have been developed over the past decades. The first lecture includes a brief introduction to the methods used to detect secondary vertices and to estimate particle lifetimes. It describes the traditional technologies, based on photographic recording in emulsions and on film of bubble chambers, and introduces fast electronic registration of signals derived from scintillating fibers, drift chambers and gaseous micro-strip chambers. The second lecture is devoted to solid state detectors. It begins with a brief introduction into semiconductor devices, and then describes the application of large arrays of strip and pixel diodes for charged particle tracking. These lectures can only serve as an introduction the topic of vertex detectors. Time and space do not allow for an in-depth coverage of many of the interesting aspects of vertex detector design and operation

  9. Smoke detectors

    International Nuclear Information System (INIS)

    Macdonald, E.

    1976-01-01

    A smoke detector is described consisting of a ventilated ionisation chamber having a number of electrodes and containing a radioactive source in the form of a foil supported on the surface of the electrodes. This electrode consists of a plastic material treated with graphite to render it electrically conductive. (U.K.)

  10. Semiconductor Detectors

    International Nuclear Information System (INIS)

    Cortina, E.

    2007-01-01

    Particle detectors based on semiconductor materials are among the few devices used for particle detection that are available to the public at large. In fact we are surrounded by them in our daily lives: they are used in photoelectric cells for opening doors, in digital photographic and video camera, and in bar code readers at supermarket cash registers. (Author)

  11. Capillary detectors

    International Nuclear Information System (INIS)

    Konijn, J.; Winter, K.; Vilain, P.; Wilquet, G.; Fabre, J.P.; Kozarenko, E.; Kreslo, I.; Goldberg, J.; Hoepfner, K.; Bay, A.; Currat, C.; Koppenburg, P.; Frekers, D.; Wolff, T.; Buontempo, S.; Ereditato, A.; Frenkel, A.; Liberti, B.; Martellotti, G.; Penso, G.; Ekimov, A.; Golovkin, S.; Govorun, V.; Medvedkov, A.; Vasil'chenko, V.

    1998-01-01

    The option for a microvertex detector using glass capillary arrays filled with liquid scintillator is presented. The status of capillary layers development and possible read-out techniques for high rate environment are reported. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

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

    KAUST Repository

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

    2017-01-01

    capture from nuclear waste. The capture mechanism was investigated by experimental and theoretical methods.Capturing radioactive organic iodides from nuclear waste is important for safe nuclear energy usage, but remains a significant challenge. Here, Li

  13. The iodide sym-porter (NIS): new perspectives in nuclear oncology

    International Nuclear Information System (INIS)

    Pourcher, Th.; Lindenthal, S.; Basquin, C.; Ferhat, O.; Marsault, R.; Carrier, P.; Koulibaly, M.; Bussiere, F.; Darcourt, J.

    2005-01-01

    The sodium iodide sym-porter (NIS) is the plasma membrane protein that mediates uptake of iodide in the thyroid and other organs such as the stomach and the salivary gland. The cloning of its cDNA allows the targeting of NIS expression into any cell using gene therapy. This enables iodide uptake and thus NIS can be used as reporter imaging for live animals. More intriguingly, this new technique has potential using radio-iodide therapy to selectively destroy tumour cells. These two approaches employ common techniques in nuclear medicine. Many experiments on cultured cells and on animals have been carried out; they established clearly the advantages of this genetically targeted radiotherapy. Recent studies employing this therapy on multiple myeloma cell lines implanted in mice or on hepato-carcinoma-bearing rats, resulted in important tumour remission. However, additional studies on NIS regulation and the use of alternative radioisotopes transported by NIS are required to further develop this promising approach. (author)

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

    KAUST Repository

    Li, Baiyan; Dong, Xinglong; Wang, Hao; Ma, Dingxuan; Tan, Kui; Shi, Zhan; Chabal, Yves J.; Han, Yu; Li, Jing

    2017-01-01

    Highly efficient capture of radioactive organic iodides (ROIs) from off-gas mixtures remains a substantial challenge for nuclear waste treatment. Current materials utilized for ROI sequestration suffer from low capacity, high cost (e.g. use of noble

  15. Leaching of iodine from composites based on epoxy resin and lead iodide

    International Nuclear Information System (INIS)

    Kalinin, N.N.; Elizarova, A.N.

    1988-01-01

    The scope for using solid composites obtained by incorporating dry powdery lead iodide and its aqueous suspension into epoxy resin for prolonged immobilization of iodine-129 under monitorable storage conditions has been assessed by a study of leaching of iodine

  16. Removal efficiency of radioactive methyl iodide on TEDA-impregnated activated carbons

    International Nuclear Information System (INIS)

    Gonzalez-Garcia, C.M.; Gonzalez, J.F.; Roman, S.

    2011-01-01

    Activated carbons were prepared by different series of carbon dioxide and steam activation from walnut shells for their optimal use as radioactive methyl iodide adsorbents in Nuclear Plants. The knowledge of the most favourable textural characteristics of the activated carbons was possible by the previous study of the commercial activated carbon currently used for this purpose. In order to increase their methyl iodide affinity, the effect of triethylenediamine impregnation was studied at 5 and 10 wt.%. The results obtained indicated that in both cases the adsorption efficiency is markedly improved by the addition of impregnant, which allows the adsorbate uptake to occur not only by physical adsorption, via non-specific interactions (as in non-impregnated carbons) but also by the specific interaction of triethylenediamine with radioactive methyl iodide. Methyl iodide retention efficiencies up to 98.1% were achieved. (author)

  17. Production of high quality sodium iodide preparations labelled with carrier free iodine-125

    International Nuclear Information System (INIS)

    Abdukayumov, M.N.; Chistyakov, P.G.; Shilin, E.A.

    2001-01-01

    Work is related to the problem of high-quality Sodium Iodide preparation production and to the choice of the peptids iodination methods with the purpose of control test developing to determine the Biological activity of the above mentioned preparation

  18. Kinetics of [123I]iodide uptake and discharge by perchlorate in studies of inhibition of iodide binding by antithyroid drugs

    International Nuclear Information System (INIS)

    McCruden, D.C.; Connell, J.M.C.; Alexander, W.D.; Hilditch, T.E.

    1985-01-01

    Thyroidal binding of iodide was studied by kinetic analysis of [ 123 ]iodide uptake and its discharge by perchlorate in 80 hyperthyroid subjects receiving antithyroid drug therapy. Five dosage regimens ranging from 5 mg carbimazole twice daily to 15 mg methimazole twice daily were studied. Binding inhibition was estimated at 5-7 h after drug as an index of the mean effect of the 12 hourly regimen. In all cases, except one in the lowest dose group, binding was found to be markedly reduced with mean binding rates ranging from 0.002 to 0.020 min -1 (normal > 0.15 min -1 ). The net clearance of iodide in the lowest dose group was reduced to a mean value near the upper limit of the euthyroid range, whereas in the highest dose group it lay at the lower limit of the euthyroid range. These results were reflected in the serum thyroid hormone response. There was a reducing incidence of inadequate control of hyperthyroidism and an increasing incidence of hypothyroidism with increasing thiourylene dose. The exit rate constant of free iodide for the various doses showed values from 0.048 to 0.055 min -1 . Correpsonding mean values for the discharge rate constant after perchlorate were 0.087 to 0.105 min -1 . This suggests that perchlorate increases the rate of iodide release from the thyroid gland. Studies at a later interval after drug (12-14 h) showed no change in discharge rate constant. This leads to the conclusion that perchlorate may further inhibit iodide binding in subjects receiving antithyroid drug therapy. (author)

  19. Method for ion exchange purification of sodium iodide solution from heavy metals and potassium microimpurities

    International Nuclear Information System (INIS)

    Smirnov, G.I.; Kachur, N.Ya.; Kostromina, O.N.; Ogorodnikova, A.A.; Khajnakov, S.A.

    1990-01-01

    A method of deep ion exchange purification of sodium iodide solution from heavy metals (iron, nickel, copper, lead) and potassium microimpurities is developed. The method includes multiple sorption of microimpurities on titanium phosphate with their subsequent desorption by sorbent processing with a solution with a solution of 3-6 N nitric acid, first, and then with a neutral solution of 2 % sodium thiosulfate. The given method permits to increase the purification degree of sodium iodide solution by 25-30 %. 2 tabs

  20. Radiolysis of cesium iodide solutions at 35 and 85 deg C

    International Nuclear Information System (INIS)

    Lucas, M.

    1981-09-01

    An aqueous solution of cesium iodide was irradiated by the gamma rays from a cobalt 60 source with a dose rate of 0.4 Mrad/hr. At 35 deg C the iodide I - is oxidized in molecular iodine I 2 but at 85 deg C the iodate IO 3 - is obtained. The aim of this work is the study of aerosols behaviour released in accidental situation of a PWR in presence of steam [fr

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

    Science.gov (United States)

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

    2013-01-01

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

  2. Predistribution of potassium iodide--the Tennessee experience

    International Nuclear Information System (INIS)

    Fowinkle, E.W.; Sell, S.H.; Wolle, R.H.

    1983-01-01

    Tennessee public health officials made a decision to predistribute potassium iodide tablets (KI) to householders in the vicinity of a nuclear power plant. The tablets would be stored until needed in the event of a radiation emergency. The officials believed that it was important to have the option available as a means of protecting nearby residents. KI, ingested before or soon after exposure to radioactive iodine, can act as a thyroid blocker to protect the gland from accepting further iodine and, therefore, the radiation. A pilot project was undertaken to deliver, door to door, a package that contained KI tablets in sufficient quantity to supply a starter dose to each member of households within a 5-mile radius of the Sequoyah nuclear power plant near Chattanooga. The package consisted of a vial of 14 130-mg tablets and a package insert from the manufacturer enclosed in a larger vial with a childproof cap. Home visitors who delivered the vials were professionals from the local public health departments, especially trained to answer questions about the project. About 66 percent of 5,591 homes accepted the medication. Extensive coverage of the project by information media was helpful in explaining local emergency plans as well as the KI distribution to the public

  3. Silver iodide sodalite for "1"2"9I immobilisation

    International Nuclear Information System (INIS)

    Vance, E.R.; Gregg, D.J.; Grant, C.; Stopic, A.; Maddrell, E.R.

    2016-01-01

    Silver iodide sodalite was initially synthesised as a fine-grained major phase in a nominally stoichiometric composition following hot isostatic pressing at 850 °C with 100 MPa and its composition, Ag_4Al_3Si_3O_1_2I, was approximately verified by scanning electron microscopy. An alternative preparative method yielded a more dense and stoichiometric AgI sodalite on sintering and HIPing. As found for AgI, the I is released from AgI sodalite much more readily in reducing water than in ordinary water. Thus in normal PCT-B tests, the I release was <0.3 g/L in water, but it was ∼70 g/L under highly reducing conditions. This is an important point with regard to can material if HIPing is used for consolidation. - Highlights: • Dense AgI sodalite has been produced by hot isostatic pressing. • The stoichiometry of AgI sodalite has been confirmed by scanning electron microscopy. • Good I immobilisation in AgI sodalite exposed to water containing Cu or Ni metal powders was determined. • AgI sodalite exposed to water containing Fe powders decomposed and released significant quantities of iodine.

  4. In situ nucleophilic substitutional growth of methylammonium lead iodide polycrystals.

    Energy Technology Data Exchange (ETDEWEB)

    Acik, Muge [Argonne National Lab. (ANL), Argonne, IL (United States). Center for Nanoscale Materials and Nanoscience and Technology Division; Alam, Todd M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Dept. of Organic Materials Science; Guo, Fangmin [Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS) and X-ray Science Division; Ren, Yang [Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS) and X-ray Science Division; Lee, Byeongdu [Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS) and X-ray Science Division; Rosenberg, Richard A. [Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS) and X-ray Science Division; Mitchell, JF [Argonne National Lab. (ANL), Argonne, IL (United States). Materials Science Division; Kinaci, Alper [Argonne National Lab. (ANL), Argonne, IL (United States). Center for Nanoscale Materials and Nanoscience and Technology Division; Chan, Maria [Argonne National Lab. (ANL), Argonne, IL (United States). Center for Nanoscale Materials and Nanoscience and Technology Division; Darling, Seth B. [Argonne National Lab. (ANL), Argonne, IL (United States). Center for Nanoscale Materials and Nanoscience and Technology Division; Univ. of Chicago, IL (United States). Inst. for Molecular Engineering

    2017-01-01

    Methylammonium lead iodide (MAPbIx) perovskites are organic-inorganic semiconductors that serve as the light-harvesting component of the photovoltaics, and are desirable with their long diffusion length yielding power conversion efficiencies of ≥22%. Conventional techniques grow perovskites by spin coating precursors on an oxide or a polymer substrate followed by annealing, however, use of high boiling point solvents and high temperatures hinder device stability and performance. Through a one-step, acid-catalyzed nucleophilic-substitutional crystal growth in polar protic solvents, we show evidence for the substrate- and annealing- free production of MAPbIx polycrystals that are metallic-lead-free with negligibly small amount of PbI2 precipitation (<10%). On the basis of this chemical composition, we have devised an in situ growth of highly air (upto ~1.5 months) and thermally-stable (≤300°C), tetragonal-phased, variable-sized polycrystals (~100 nm-10 μm) amendable for large-area deposition, and ultimately, large-scale manufacturing. This method is encouraging for stable optoelectronic devices, and leads to energy-efficient and low-cost processing.

  5. Slow hot carrier cooling in cesium lead iodide perovskites

    Science.gov (United States)

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

    2017-10-01

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

  6. Kinetics of the thermal decomposition of nickel iodide

    International Nuclear Information System (INIS)

    Nakajima, Hayato; Shimizu, Saburo; Onuki, Kaoru; Ikezoe, Yasumasa; Sato, Shoichi

    1984-01-01

    Thermal decomposition kinetics of NiI 2 under constant I 2 partial pressure was studied by thermogravimetry. The reaction is considered as a reaction step of the thermochemical hydrogen production process in the Ni-I-S system. At temperatures from 775K to 869K and under I 2 pressures from 0 to 960Pa, the decomposition started at the NiI 2 pellet surface and the reactant-product interface moved interior at a constant rate until the decomposed fraction, α, reached 0.6. The overall reaction rate at a constant temperature can be expressed as the difference of the constant decomposition (forward) rate, which is proportional to the equilibrium dissociation pressure of NiI 2 , and the iodide formation (backward) rate, which is proportional to the I 2 pressure. The apparent activation energy of the decomposition was 147 kJ.mol -1 , which is very close to the heat of reaction, 152 kJ.mol -1 calculated from the equilibrium dissociation pressure. The electron microscopic observations, revealed that the reaction product obtained by decomposing NiI 2 under pure He atomosphere was composed of relatively well grown cubic Ni crystals. Whereas, the decomposed product obtained under I 2 -He mixture was composed of larger but disordered crystals. (author)

  7. Persistent photovoltage in methylammonium lead iodide perovskite solar cells

    Directory of Open Access Journals (Sweden)

    A. Baumann

    2014-08-01

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

  8. MCNP Techniques for Modeling Sodium Iodide Spectra of Kiwi Surveys

    International Nuclear Information System (INIS)

    Robert B Hayes

    2007-01-01

    This work demonstrates how MCNP can be used to predict the response of mobile search and survey equipment from base principles. The instrumentation evaluated comes from the U.S. Department of Energy's Aerial Measurement Systems. Through reconstructing detector responses to various point-source measurements, detector responses to distributed sources can be estimated through superposition. Use of this methodology for currently deployed systems allows predictive determinations of activity levels and distributions for common configurations of interest. This work helps determine the quality and efficacy of certain surveys in fully characterizing an effected site following a radiological event of national interest

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

    Science.gov (United States)

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

    2013-02-04

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

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

    Directory of Open Access Journals (Sweden)

    Magnus Willander

    2013-02-01

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

  11. Studies of selected transuranium and lanthanide tri-iodides under pressure using absorption spectrophotometry

    International Nuclear Information System (INIS)

    Haire, R.G.; Young, J.P.; Peterson, J.R.; Tennessee Univ., Knoxville; Benedict, U.

    1987-01-01

    The anhydrous tri-iodides of plutonium, americium and curium under pressure have been investigated using absorption spectrophotometry. These initial studies on plutonium and curium tri-iodides together with the published data for americium tri-iodide show that the rhombohedral form of these compounds (BiI 3 -type structure) can be converted to the orthorhombic form (PuBr 3 -type structure) by applying pressure at room temperature. Absorption spectrophotometry can often differentiate between two crystallographic forms of a material and has been used in the present high-pressure studies to monitor the effects of pressure on the tri-iodides. A complication in these studies of the tri-iodides is a significant shift of their absorption edges with pressure from the near UV to the visible spectral region. With curium tri-iodide this shift causes interference with the major f-f absorption peaks and precludes identification by absorption spectrophotometry of the high pressure phase of CmI 3 . (orig.)

  12. Mechanistic aspects of ingested chlorine dioxide on thyroid function: impact of oxidants on iodide metabolism

    International Nuclear Information System (INIS)

    Bercz, J.P.; Jones, L.L.; Harrington, R.M.; Bawa, R.; Condie, L.

    1986-01-01

    Toxicological studies dealing with recent findings of health effects of drinking water disinfectants are reviewed. Experiments with monkeys and rodents indicate that the biological activity of ingested disinfectants is expressed via their chemical interaction with the mucosal epithelia, secretory products, and nutritional contents of the alimentary tract. Evidence exists that a principal partner of this redox interaction is the iodide of nutritional origin that is ubiquitous in the gastrointestinal tract. Thus the observation that subchronic exposure to chlorine dioxide (ClO 2 ) in drinking water decreases serum thyroxine levels in mammalian species can be best explained with changes produced in the chemical form of the bioavailable iodide. Ongoing and previously reported mechanistic studies indicate that oxidizing agents such as chlorine-based disinfectants oxidize the basal iodide content of the gastrointestinal tract. The resulting reactive iodine species readily attaches to organic matter by covalent bonding. Evidence suggests that the extent to which such iodinated organics are formed is proportional to the magnitude of the electromotive force and stoichiometry of the redox couple between iodide and the disinfectant. Because the extent of thyroid uptake of the bioavailable iodide does not decrease during ClO 2 ingestion, it seems that ClO 2 does not cause iodide deficiency of sufficient magnitude to account for the decease in hormonogenesis. Absorption of one or more of iodinated molecules, e.g., nutrient, hormones, or cellular constituents of the alimentary tract having thyromimetic or thyroid inhibitory properties, is a better hypothesis for the effects seen

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

    Directory of Open Access Journals (Sweden)

    S. Pechtl

    2007-01-01

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

  14. Lead iodide X-ray and gamma-ray spectrometers for room and high temperature operation

    International Nuclear Information System (INIS)

    Hermon, H.; James, R.B.; Lund, J.

    1998-01-01

    In this study the authors report on the results of the investigation of lead iodide material properties. The effectiveness of a zone refining purification method on the material purity is determined by ICP-MS and ICP-OES and correlated to the electrical and physical material properties. They show that this zone refining method is very efficient in removing impurities from lead iodide, and they also determine the segregation coefficient for some of these impurities. Triple axis X-ray diffraction (TAD) analysis has been used to determine the crystalline perfection of the lead iodide after applying various cutting, etching and fabrication methods. The soft lead iodide crystal was found to be damaged when cleaved by a razor blade, but by using a diamond wheel saw, followed by etching, the crystallinity of the material was much improved, as observed by TAD. Low temperature photoluminescence also indicates an improvement in the material properties of the purified lead iodide. Electrical properties of lead iodide such as carrier mobility, were calculated based on carrier-phonon scattering. The results for the electrical properties were in good agreement with the experimental data

  15. S-Mercuration of rat sorbitol dehydrogenase by methylmercury causes its aggregation and the release of the zinc ion from the active site.

    Science.gov (United States)

    Kanda, Hironori; Toyama, Takashi; Shinohara-Kanda, Azusa; Iwamatsu, Akihiro; Shinkai, Yasuhiro; Kaji, Toshiyuki; Kikushima, Makoto; Kumagai, Yoshito

    2012-11-01

    We previously developed a screening method to identify proteins that undergo aggregation through S-mercuration by methylmercury (MeHg) and found that rat arginase I is a target protein for MeHg (Kanda et al. in Arch Toxicol 82:803-808, 2008). In the present study, we characterized another S-mercurated protein from a rat hepatic preparation that has a subunit mass of 42 kDa, thereby facilitating its aggregation. Two-dimensional SDS-polyacrylamide gel electrophoresis and subsequent peptide mass fingerprinting using matrix-assisted laser desorption and ionization time-of-flight mass spectrometry revealed that the 42 kDa protein was NAD-dependent sorbitol dehydrogenase (SDH). With recombinant rat SDH, we found that MeHg is covalently bound to SDH through Cys44, Cys119, Cys129 and Cys164, resulting in the inhibition of its catalytic activity, release of zinc ions and facilitates protein aggregation. Mutation analysis indicated that Cys44, which ligates the active site zinc atom, and Cys129 play a crucial role in the MeHg-mediated aggregation of SDH. Pretreatment with the cofactor NAD, but not NADP or FAD, markedly prevented aggregation of SDH. Such a protective effect of NAD on the aggregation of SDH caused by MeHg is discussed.

  16. Mercuric chloride-induced alterations of levels of noradrenaline, dopamine, serotonin and acetylcholine esterase activity in different regions of rat brain during postnatal development

    Energy Technology Data Exchange (ETDEWEB)

    Lakshmana, M.K. (Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bangalore (India)); Desiraju, T. (Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bangalore (India)); Raju, T.R. (Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bangalore (India))

    1993-07-01

    Wistar rats were fed mercuric chloride, 4 mg/kg body weight per day chronically from postnatal day 2 to 60 by gastric intubation. Mercury consumption was then discontinued until 170 days to allow time for recovery. Since mercury caused reduction in body weight, an underweight group was also included besides the normal saline group. Levels of noradrenaline (NA), dopamine (DA), 5-hydroxytryptamine (5-HT) and the activity of acetylcholine esterase (AChE) were assayed in various brain regions in different age groups. By 60 days of age, the mercury group showed elevations of NA levels in olfactory bulb (OB), visual cortex (VC) and brain stem (BS) but not in striatumaccumbens (SA) and hippocampus (HI). DA levels were also increased in OB, HI, VC and BS but not in SA. AChE activity was decreased in the mercury group only in HI and VC at 20 days of age. The Mercury group showed no behavioural abnormality outwardly; however, operant conditioning relevated a dificiency in performance. Nevertheless, all these changes disappeared after discontinuation of mercury intake. Thus the changes occurring in the brain at this level of oral mercuric chloride intake seem to reflect adaptive neural mechanisms rather than pathological damage. (orig.)

  17. Neutron detector

    Science.gov (United States)

    Stephan, Andrew C [Knoxville, TN; Jardret,; Vincent, D [Powell, TN

    2011-04-05

    A neutron detector has a volume of neutron moderating material and a plurality of individual neutron sensing elements dispersed at selected locations throughout the moderator, and particularly arranged so that some of the detecting elements are closer to the surface of the moderator assembly and others are more deeply embedded. The arrangement captures some thermalized neutrons that might otherwise be scattered away from a single, centrally located detector element. Different geometrical arrangements may be used while preserving its fundamental characteristics. Different types of neutron sensing elements may be used, which may operate on any of a number of physical principles to perform the function of sensing a neutron, either by a capture or a scattering reaction, and converting that reaction to a detectable signal. High detection efficiency, an ability to acquire spectral information, and directional sensitivity may be obtained.

  18. Ionization detector

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, E E

    1976-02-27

    This invention concerns a fire detection system making use of a beta source. The ionisation detector includes a first and second chamber respectively comprising a first and second electrode, preferably a plate, with a common electrode separating the first and second chamber. Communication is provided between these chambers through a set of orifices and each chamber also has a set of orifices for communication with the ambient atmosphere. One or both chambers can comprise a particle source, preferably beta. The detector also has an adjustable electrode housed in one of the chambers to regulate the voltage between the fixed electrode of this chamber and the common electrode located between the chambers. The electrodes of the structure are connected to a detection circuit that spots a change in the ionisation current when a fire alarm condition arises. The detection circuit of a new type includes a relaxation oscillator with a programmable unijunction transistor and a light emitting diode.

  19. MUST detector

    International Nuclear Information System (INIS)

    Blumenfeld, Y.; Auger, F.; Sauvestre, J.E.

    1999-01-01

    The IPN-Orsay, in collaboration with the SPhN-Saclay and the DPTA Bruyeres, has built an array of 8 telescopes based on Si-strip technology for the study of direct reactions induced by radioactive beams. The detectors are described, along with the compact high density VXI electronics and the stand-alone data acquisition system developed in the laboratory. One telescope was tested using an 40 Ar beam and the measured performances are discussed. (authors)

  20. Radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Ohata, Shuichi; Takeuchi, Yoji

    1968-10-30

    Herein disclosed is an ionization chamber the airtightness of which can be readily tested. The ionization chamber is characterized in that a small amount of helium gas is filled in the chamber in combination with other ionization gases such as argon gas, xenon gas and the like. Helium leakage from the chamber is measured by a known helium gas sensor in a vacuum vessel. Hence the long term drift of the radiation detector sensitivity may be determined.

  1. Hydrogen iodide processing section in a thermochemical water-splitting iodine-sulfur process using a multistage hydrogen iodide decomposer

    International Nuclear Information System (INIS)

    Ohashi, Hirofumi; Sakaba, Nariaki; Imai, Yoshiyuki; Kubo, Shinji; Sato, Hiroyuki; Tachibana, Yukio; Kunitomi, Kazuhiko; Kato, Ryoma

    2009-01-01

    A multistage hydrogen iodide (HI) decomposer (repetition of HI decomposition reaction and removal of product iodine by a HIx solution) in a thermochemical water-splitting iodine-sulfur process for hydrogen production using high-temperature heat from the high-temperature gas-cooled reactor was numerically evaluated, especially in terms of the flow rate of undecomposed HI and product iodine at the outlet of the decomposer, in order to reduce the total heat transfer area of heat exchangers for the recycle of undecomposed HI and to eliminate components for the separation. A suitable configuration of the multistage HI decomposer was countercurrent rather than concurrent, and the HIx solution from an electro-electro dialysis at a low temperature was a favorable feed condition for the multistage HI decomposer. The flow rate of undecomposed HI and product iodine at the outlet of the multistage HI decomposer was significantly lower than that of the conventional HI decomposer, because the conversion was increased, and HI and iodine were removed by the HIx solution. Based on this result, an alternative HI processing section using the multistage HI decomposer and eliminating some recuperators, coolers, and components for the separation was proposed and evaluated. The total heat transfer area of heat exchangers in the proposed HI processing section could be reduced to less than about 1/2 that in the conventional HI processing section. (author)

  2. Shock-resistant gamma-ray detector tube

    International Nuclear Information System (INIS)

    1979-01-01

    A simple durable scintillation detector is described which, it is claimed, offers a solution to the shock resistance problems encountered when gamma detectors are used for deep bore hole well logging or in space vehicles. The shock resistant detector consists of an elongate sodium iodide scintillation crystal and rigid metal container with a round glass optical window at one end of the container and a metal end closure cap at the opposite end. An elastic rubber compression pad is provided between the end cap and the scintillation crystal to bias the crystal axially toward the glass window. An extension transparent silicone rubber light pipe of substantial axial thickness permanently couples the optical window to the crystal while allowing substantial movement under high g forces. (U.K.)

  3. Effects of dietary [alpha]-tocopherol and [beta]-carotene on lipid peroxidation induced by methyl mercuric chloride in mice

    Energy Technology Data Exchange (ETDEWEB)

    Raun Andersen, H; Andersen, O [Department of Environmental Medicine, University of Odense, Odense (Denmark)

    1993-01-01

    Exposure of male CBA mice to methyl mercuric chloride, CH[sub 3]HgCl, (10-40 mg/l in drinking water) for 2 weeks resulted in dose-related Hg deposition and enhanced lipid peroxidation in liver, kidney and brain. Mice were fed well-defined semisynthetic diets containing different levels of [alpha]-tocopherol (10, 100 or 1000 mg/kg) or [beta]-carotene (1000, 10,000 or 100,000 IU/kg) for four weeks, two groups on each diet. The concentration of [alpha]-tocopherol and [beta]-carotene used corresponded to deficient, normal and high levels. During the last two weeks, one group on each diet was given 40 mg CH[sub 3]HgCl/l of drinking water. High dietary [alpha]-tocopherol protected against CH[sub 3]HgCl induced hepatic lipid peroxidation, whereas the [alpha]-tocopherol deficient diet further enhanced CH[sub 3]HgCl induced hepatic lipid peroxidation. Similar, though statistically non-significant effects occurred in the kidneys, [alpha]-tocopherol did not protect against CH[sub 3]HgCl induced lipid peroxidation in the brain. Excess dietary [beta]-carotene further enhanced CH[sub 3]HgCl induced lipid peroxidation in liver, kidney and brain. CH[sub 3]HgCl significantly decreased the activity of total glutathione peroxidase (T-GSH-Px) and Se-dependent glutathione peroxidase (Se-GSH-Px) in the kidneys in all dietary groups. High dietary [alpha]-tocopherol enhanced the activity of Se-GSH-Px in liver and kidney compared to the activity in mice fed the normal level of [alpha]-tocopherol. This occurred in mice exposed to CH[sub 3]-HgCl as well as in unexposed mice, and the difference between CH[sub 3]HgCl exposed and unexposed mice was not diminished. High dietary [alpha]-tocopherol increased the activity of both Se-GSH-Px and T-GSH-Px in the brain of CH[sub 3]HgCl-exposed mice. The dietary level of [beta]-carotene did not affect the activity of the two enzymes in the organs investigated. (au) (43 refs.).

  4. Effects of dietary α-tocopherol and β-carotene on lipid peroxidation induced by methyl mercuric chloride in mice

    International Nuclear Information System (INIS)

    Raun Andersen, H.; Andersen, O.

    1993-01-01

    Exposure of male CBA mice to methyl mercuric chloride, CH 3 HgCl, (10-40 mg/l in drinking water) for 2 weeks resulted in dose-related Hg deposition and enhanced lipid peroxidation in liver, kidney and brain. Mice were fed well-defined semisynthetic diets containing different levels of α-tocopherol (10, 100 or 1000 mg/kg) or β-carotene (1000, 10,000 or 100,000 IU/kg) for four weeks, two groups on each diet. The concentration of α-tocopherol and β-carotene used corresponded to deficient, normal and high levels. During the last two weeks, one group on each diet was given 40 mg CH 3 HgCl/l of drinking water. High dietary α-tocopherol protected against CH 3 HgCl induced hepatic lipid peroxidation, whereas the α-tocopherol deficient diet further enhanced CH 3 HgCl induced hepatic lipid peroxidation. Similar, though statistically non-significant effects occurred in the kidneys, α-tocopherol did not protect against CH 3 HgCl induced lipid peroxidation in the brain. Excess dietary β-carotene further enhanced CH 3 HgCl induced lipid peroxidation in liver, kidney and brain. CH 3 HgCl significantly decreased the activity of total glutathione peroxidase (T-GSH-Px) and Se-dependent glutathione peroxidase (Se-GSH-Px) in the kidneys in all dietary groups. High dietary α-tocopherol enhanced the activity of Se-GSH-Px in liver and kidney compared to the activity in mice fed the normal level of α-tocopherol. This occurred in mice exposed to CH 3 -HgCl as well as in unexposed mice, and the difference between CH 3 HgCl exposed and unexposed mice was not diminished. High dietary α-tocopherol increased the activity of both Se-GSH-Px and T-GSH-Px in the brain of CH 3 HgCl-exposed mice. The dietary level of β-carotene did not affect the activity of the two enzymes in the organs investigated. (au) (43 refs.)

  5. Iodide behaviour in hard clay rocks under controlled physico-chemical conditions at different concentrations

    International Nuclear Information System (INIS)

    Frasca, B.; Savoye, S.; Wittebroodt, C.; Leupin, O.X.; Descostes, M.; Grenut, B.; Meier, P.; Michelot, J.L.

    2010-01-01

    Document available in extended abstract form only. With a half-life of 1.6 10 7 years, its high mobility and its potential to accumulate in the biosphere, iodine-129 is considered, from safety assessment calculations for radioactive waste repositories, to be one of the main radiological dose contributors. Based on the findings of previous studies, iodide, especially at low concentrations, seems to be migrating at a slower rate in clay rock than Cl-36. The cause of this retardation regarding the diffusion of iodide versus chloride is not yet understood but several hypotheses are point towards sorption on natural organic matter (NOM), pyrite or redox reactions. Oxidation of iodide would form IO 3 - which is known to have a higher sorption affinity on several soils and sediment samples than iodide. The present project aims at exploring the effect on the iodide behaviour of two parameters: (i) the initial concentration of iodide and (ii) the amount of NOM contained in the argillite samples. Such an investigation is carried out on Tournemire argillite by means of both batch and through-diffusion experiments. The main challenge is to exclude as much as possible the occurrence of any experimental artefact that could induce iodide uptake (oxygen contamination, dissolution/precipitation of carbonate phases). Regarding redox conditions and rock equilibrium, all the experiments were carried out under physico-chemical conditions as close as possible to those prevailing in field. Using a glove box with an atmosphere of N 2 /CO 2 (respectively 99.6% and 0.4%), we preserved the experiments from oxygen and maintained the calculated in-situ carbonate equilibrium. At first, four through-diffusion experiments with the non-sorbing tracers HTO and Cl-36 were performed to allow the diffusive parameters of each sample to be defined. Afterwards, iodide was injected in the diffusion cells at four different concentrations (10 -6 M to 10 -3 M). Thus, the comparison of the incoming fluxes of

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

    Science.gov (United States)

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

    2012-07-01

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

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

    Directory of Open Access Journals (Sweden)

    I Wayan Hartadi Noor

    2013-11-01

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

  8. Fabrication of radiation detector using PbI2 crystals

    International Nuclear Information System (INIS)

    Shoji, T.; Ohba, K.; Suehiro, T.; Hiratate, Y.

    1995-01-01

    Radiation detectors have been fabricated from lead iodide (PbI 2 ) crystals grown by two methods: zone melting and Bridgman methods. In response characteristics of the detector fabricated from crystals grown by the zone melting method, a photopeak for γ-rays from an 241 Am source (59.5 KeV) has been clearly observed with applied detector bias of 500 V at room temperature. The hole drift mobility is estimated to be about 5.5 cm 2 /Vs from measurement of pulse rise time for 5.48 MeV α-rays from 241 Am. By comparing the detector bias versus saturated peak position of the PbI 2 detector with that of CdTe detector, the average energy for producing electron-hole pairs is estimated to be about 8.4 eV for the PbI 2 crystal. A radiation detector fabricated from PbI 2 crystals grown by the Bridgman method, however, exhibited no response for γ-rays

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

    International Nuclear Information System (INIS)

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

    1987-01-01

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

  10. The method of determination of micro quantities of labelled iodide in Na125 I carrier free solution

    International Nuclear Information System (INIS)

    Kholbaev, A.Kh.; Shilin, E.A.

    1996-01-01

    The analytical method was elaborated with the purpose to increase detection limit and radiation safety of labelled iodide determination. The method includes oxidation of iodide by iodate in diluted sulphur acid solution with molar concentration 0,03-0,04/moles/litre at molar ratio of iodide to iodate I - :IO - 3 1:12,5. The extraction of I 2 produced is done by toluene. (author)

  11. Smoke detectors

    International Nuclear Information System (INIS)

    Fung, C.K.

    1981-01-01

    This describes a smoke detector comprising a self-luminous light source and a photosensitive device which is so arranged that the light source is changed by the presence of smoke in a detecting region. A gaseous tritium light source is used. This consists of a borosilicate glass bulb with an internal phosphor coating, filled with tritium gas. The tritium emits low energy beta particles which cause the phosphor to glow. This is a reliable light source which needs no external power source. The photosensitive device may be a phototransistor and may drive a warning device through a directly coupled transistor amplifier. (U.K.)

  12. Study on the Electrochemical Behavior of Iodide at Platinum Electrode in Potassium Chlorate Solution

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Sang Hyuk; Yeon, Jei Won; Song, Kyu Seok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    Radioactive iodine-131, is one of the most hazardous fission products which could be released from fuels of nuclear reactors during the severe accident of nuclear power plants. Due to its high radioactivity, high fission yield (2.8%) and hazardous biological effects, the behavior of iodine has been taken interests in many research groups. Iodine is known to be released from the fuels as a cesium iodide form, CsI. And, as nuclear fuels are mostly placed in the water pool, it is easily dissolved in the water after released from the fuels. In water, iodide anion could be oxidized into molecular iodine. As the molecular iodine is a volatile species and the oxidizing rate is affected by many environmental facts such as pH, radiolysis products and temperature, the oxidation reaction of the iodide ion has been considered as an important chemical reaction related to the severe accident of nuclear power plants In present work, the electrochemical behavior of iodide anion was observed by using cyclic voltammetric technique in potassium chlorate solutions. We observed two different oxidation waves in the oxidation potential region. From the comparison with the previous reported results, one is regarded as the oxidation of iodide into molecular iodine. The other is evaluated to be the formation of high-valent iodine-containing compounds

  13. Estradiol decreases iodide uptake by rat thyroid follicular FRTL-5 cells

    Directory of Open Access Journals (Sweden)

    Furlanetto T.W.

    2001-01-01

    Full Text Available Estradiol has well-known indirect effects on the thyroid. A direct effect of estradiol on thyroid follicular cells, increasing cell growth and reducing the expression of the sodium-iodide symporter gene, has been recently reported. The aim of the present investigation was to study the effect of estradiol on iodide uptake by thyroid follicular cells, using FRTL-5 cells as a model. Estradiol decreased basal iodide uptake by FRTL-5 cells from control levels of 2.490 ± 0.370 to 2.085 ± 0.364 pmol I-/µg DNA at 1 ng/ml (P<0.02, to 1.970 ± 0.302 pmol I-/µg DNA at 10 ng/ml (P<0.003, and to 2.038 ± 0.389 pmol I-/µg DNA at 100 ng/ml (P<0.02. In addition, 4 ng/ml estradiol decreased iodide uptake induced by 0.02 mIU/ml thyrotropin from 8.678 ± 0.408 to 7.312 ± 0.506 pmol I-/µg DNA (P<0.02. A decrease in iodide uptake by thyroid cells caused by estradiol has not been described previously and may have a role in goiter pathogenesis.

  14. Monitoring of fluoride and iodide levels in drinking water using ion selective electrodes

    International Nuclear Information System (INIS)

    Ahmed, R.; Viqar-Un-Nisa; Hussain, M.; Tanwir, R.; Qureshi, S.A.

    2004-01-01

    Fluoride and iodide, the most important constituents of drinking water are essential as well as toxic depending on their levels. For their analysis in water mostly ion-selective electrodes, spectrophotometry, titrimetry and coulometry etc; have been used and literature has been briefly reviewed. Ion-selective electrodes offer an efficient method for the measurement of the two halides and were mostly used during this work. Fabrication of these electrodes is briefly described. Comparison of results obtained by ion selective electrode and coulometry is given. Recoveries of the added fluoride ions from the samples were good. A large number of water samples from Rawalpindi-Islamabad area were analyzed for fluoride and iodide. Levels of fluoride and iodide from two main water reservoirs of Rawalpindi and Islamabad are reported before and after treatment. Both surface and ground water samples were analyzed and results are compared and discussed. Some samples from northern areas were also analyzed for iodide and fluoride and compared. Intake of fluoride and iodide from water of different areas is also compared. Water samples, which caused bone deformation in certain areas in Punjab due to excess fluoride, were also analyzed for fluoride and results are presented. (author)

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

    Directory of Open Access Journals (Sweden)

    VLADIMIR D. JOVIĆ

    2011-02-01

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

  16. Alpha-lipoic acid induces sodium iodide symporter expression in TPC-1 thyroid cancer cell line

    International Nuclear Information System (INIS)

    Choi, Hyun-Jeung; Kim, Tae Yong; Ruiz-Llorente, Sergio; Jeon, Min Ji; Han, Ji Min; Kim, Won Gu; Shong, Young Kee; Kim, Won Bae

    2012-01-01

    Introduction: Patients with metastatic thyroid cancers that do not uptake iodine need effective therapeutic option. Differentiation-inducing agents have been tried to restore functional expression of sodium iodide symporter (NIS) without success. Our objective was to assess the effect of alpha-lipoic acid (ALA), known as potential antioxidant, on expression of sodium iodide symporter in thyroid cancer cells. Methods: Human thyroid cancer-derived cell lines, TPC-1, were treated with ALA, and changes in NIS mRNA and protein expression were measured. ALA's effect on NIS gene promoter was evaluated, and functional NIS expression was assessed by iodide uptake assay. Results: Treatment with ALA increased NIS mRNA expression up to ten folds of control dose-dependently after 24 h of exposure. ALA increased NIS promoter activity, and increased iodide uptake by 1.6 fold. ALA induced expression of NIS protein, but had no significant effect on the plasma membrane trafficking. ALA increased phosphorylation of CREB and nuclear translocation of pCREB, and co-treatment of ALA and trichostatin A increased iodide uptake by three folds in TPC-1 cells. Conclusions: ALA is a potential agent to increase NIS transcription in TPC-1. It could be used as an adjunctive agent to increase efficacy of radioiodine therapy if combined with a strategy to increase NIS protein trafficking to cell membrane.

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

    Science.gov (United States)

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

    2017-09-07

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

  18. An investigation of sodium iodide solubility in sodium-stainless steel systems

    International Nuclear Information System (INIS)

    Sagawa, Norihiko; Tashiro, Suguru

    1996-01-01

    Sodium iodide and major constituents of stainless steel in sodium are determined by using the steel capsules to obtain a better understanding on contribution of the constituents to the apparent iodide solubility in sodium. The capsule loaded with 20 g sodium and 0.1 - 0.3 g powder of sodium iodide is heated at its upper part in a furnace and cooled at its bottom on brass plates to establish a large temperature gradient along the capsule tube. After a given period of equilibration, the iodide and constituents are fixed in solidified sodium by quick quenching of the capsules. Sodium samples are taken from the sectioned capsule tube and submitted to sodium dissolution by vaporized water for determination of the iodine and to vacuum distillation for determination of the metal elements. Iron and nickel concentrations are observed to be lower in the samples at higher iodine concentrations. Chromium and manganese concentrations are seen to be insensitive to the iodine concentrations. The observations can be interpreted by a model that sodium oxide combines with metal iodide in sodium to form a complex compound and with consideration that the compound will fall and deposit onto the bottom of the capsule by thermal diffusion. (author)

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

    KAUST Repository

    Li, Baiyan

    2017-09-01

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

  20. The value of iodide as a parameter in the chemical characterisation of groundwaters

    Science.gov (United States)

    Lloyd, J. W.; Howard, K. W. F.; Pacey, N. R.; Tellam, J. H.

    1982-06-01

    Brackish and saline groundwaters can severely constrain the use of fresh groundwaters. Their chemical characterisation is important in understanding the hydraulic conditions controlling their presence in an aquifer. Major ions are frequently of limited value but minor ions can be used. Iodide in groundwater is particularly significant in many environments due to the presence of soluble iodine in aquifer matrix materials. Iodide is found in groundwaters in parts of the English Chalk aquifer in concentrations higher than are present in modern seawater. Its presence is considered as a indication of groundwater residence and is of use in the characterisation of fresh as well as saline waters. Under certain circumstances modern seawater intrusion into aquifers along English estuaries produces groundwaters which are easily identified due to iodide enrichment from estuarine muds. In other environments iodide concentrations are of value in distinguishing between groundwaters in limestones and shaly gypsiferous rocks as shown by a study in Qatar, while in an alluvial aquifer study in Peru iodide has been used to identify groundwaters entering the aquifer from adjacent granodiorites.

  1. Stable iodide doping induced by photonic curing for carbon nanotube transparent conductive films

    Science.gov (United States)

    Wachi, Atsushi; Nishikawa, Hiroyuki; Zhou, Ying; Azumi, Reiko

    2018-06-01

    Doping has become crucial for achieving stable and high-performance conductive transparent carbon nanotube (CNT) films. In this study, we systematically investigate the doping effects of a few materials including alkali metal iodides, nonmetal iodide, and metals. We demonstrate that photonic curing can enhance the doping effects, and correspondingly improve the conductivity of CNT films, and that such iodides have better doping effects than metals. In particular, doping with a nonmetal compound (NH4I) shows the largest potential to improve the conductivity of CNT films. Typically, doping with metal iodides reduces the sheet resistance (R S) of CNT films with 70–80% optical transmittances at λ = 550 nm from 600–2400 to 250–440 Ω/square, whereas doping with NH4I reduces R S to 57 and 84 Ω/square at 74 and 84% optical transmittances, respectively. Interestingly, such a doped CNT film exhibits only a slight increase in sheet resistance under an extreme environment of high temperature (85 °C) and high relative humidity (85%) for 350 h. The results suggest that photonic-curing-induced iodide doping is a promising approach to producing high-performance conductive transparent CNT films.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-31

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

  3. Functional activity of human sodium/iodide symporter in tumor cell lines

    International Nuclear Information System (INIS)

    Petrich, T.; Knapp, W.H.; Poetter, E.

    2003-01-01

    Aim: The sodium/iodide symporter (NIS) actively transports iodide into thyrocytes. Thus, NIS represents a key protein for diagnosis and radioiodine therapy of differentiated thyroid cancer. Additionally, in the future the NIS gene may be used for cancer gene therapy of non-thyroid-derived malignancies. In this study we evaluated the functionality of NIS with respect to iodide uptake in a panel of tumor cell lines and compared this to gene transfer efficiency. Methods: A human NIS-containing expression vector and reporter-gene vectors encoding and beta;-Galactosidase- or EGFP were used for transient transfection of 13 tumor cell lines. Following transfection measurements of NIS-mediated radioiodide uptake using Na 125 I and of transfection efficiency were performed. The latter included β;-Galactosidase activity measurements using a commercial kit and observation by fluorescence microscopy for EGFP expression. Results: In contrast to respective parental cells, most NIS-transfected cell lines displayed high, perchlorate-sensitive radioiodide uptake. Differences in radioiodide uptake between cell lines apparently corresponded to transfection efficiencies, as judged from reporter-gene assays. Conclusion: With respect to iodide uptake we provide evidence that NIS is functional in different cellular context. As iodide uptake capacity appears to be well correlated to gene transfer efficiency, cell type-specific actions on NIS (e. g. post-translational modification such as glycosylation) are not inhibitory to NIS function. Our data support the promising role of NIS in cancer gene therapy strategies. (orig.)

  4. Pulse Rise Time Characterization of a High Pressure Xenon Gamma Detector for use in Resolution Enhancement

    CERN Document Server

    Troyer, G L

    2000-01-01

    High pressure xenon ionization chamber detectors are possible alternatives to traditional thallium doped sodium iodide (NaI(Tl)) and hyperpure germanium as gamma spectrometers in certain applications. Xenon detectors incorporating a Frisch grid exhibit energy resolutions comparable to cadmium/zinc/telluride (CZT) (e.g. 2% (at) 662keV) but with far greater sensitive volumes. The Frisch grid reduces the position dependence of the anode pulse risetimes, but it also increases the detector vibration sensitivity, anode capacitance, voltage requirements and mechanical complexity. We have been investigating the possibility of eliminating the grid electrode in high-pressure xenon detectors and preserving the high energy resolution using electronic risetime compensation methods. A two-electrode cylindrical high pressure xenon gamma detector coupled to time-to-amplitude conversion electronics was used to characterize the pulse rise time of deposited gamma photons. Time discrimination was used to characterize the pulse r...

  5. Breast cancer detection rates using four different types of mammography detectors

    Energy Technology Data Exchange (ETDEWEB)

    Mackenzie, Alistair; Warren, Lucy M.; Dance, David R.; Young, Kenneth C. [Royal Surrey County Hospital, National Coordinating Centre for the Physics in Mammography (NCCPM), Guildford (United Kingdom); University of Surrey, Department of Physics, Guildford (United Kingdom); Wallis, Matthew G. [Cambridge University Hospitals NHS Foundation Trust, Cambridge (United Kingdom); NIHR Cambridge Biomedical Research Centre, Cambridge Breast Unit, Cambridge (United Kingdom); Cooke, Julie [Jarvis Breast Screening and Diagnostic Centre, Guildford (United Kingdom); Given-Wilson, Rosalind M. [St George' s Healthcare NHS Trust, Department of Radiology, London (United Kingdom); Chakraborty, Dev P. [University of Pittsburgh, Department of Radiology, Pittsburgh, PA (United States); Halling-Brown, Mark D. [Royal Surrey County Hospital, Scientific Computing, Department of Medical Physics, Guildford (United Kingdom); Looney, Padraig T. [Royal Surrey County Hospital, National Coordinating Centre for the Physics in Mammography (NCCPM), Guildford (United Kingdom)

    2016-03-15

    To compare the performance of different types of detectors in breast cancer detection. A mammography image set containing subtle malignant non-calcification lesions, biopsy-proven benign lesions, simulated malignant calcification clusters and normals was acquired using amorphous-selenium (a-Se) detectors. The images were adapted to simulate four types of detectors at the same radiation dose: digital radiography (DR) detectors with a-Se and caesium iodide (CsI) convertors, and computed radiography (CR) detectors with a powder phosphor (PIP) and a needle phosphor (NIP). Seven observers marked suspicious and benign lesions. Analysis was undertaken using jackknife alternative free-response receiver operating characteristics weighted figure of merit (FoM). The cancer detection fraction (CDF) was estimated for a representative image set from screening. No significant differences in the FoMs between the DR detectors were measured. For calcification clusters and non-calcification lesions, both CR detectors' FoMs were significantly lower than for DR detectors. The calcification cluster's FoM for CR NIP was significantly better than for CR PIP. The estimated CDFs with CR PIP and CR NIP detectors were up to 15 % and 22 % lower, respectively, than for DR detectors. Cancer detection is affected by detector type, and the use of CR in mammography should be reconsidered. (orig.)

  6. Histochemical demonstration of mercury in the olfactory system of salmon (Salmo salar L.) following treatments with dietary methylmercuric chloride and dissolved mercuric chloride

    DEFF Research Database (Denmark)

    Baatrup, E; Døving, K B

    1991-01-01

    The deposition of organic and inorganic mercury compounds was studied histochemically in the salmon (Salmo salar L.) olfactory system. One group of salmon was given fodder pellets containing methylmercuric chloride (CH3HgCl, 99 micrograms Hg/g) for 4 weeks. Other groups of fish were exposed...... to dissolved mercuric chloride (HgCl2, 270 micrograms Hg/liter) for 2, 6, and 12 hr, respectively. In both series of experiments, the radioisotope 203Hg was included in order to determine the accumulation of mercury in the olfactory system. Gamma-spectrometry showed that both mercury compounds accumulated...... in the olfactory rosettes and their nerves. Tissue sections from the rosettes and olfactory nerves were subjected to autometallographic silver enhancement, thereby rendering mercury deposits visible for light and electron microscopy. Microscopic analysis demonstrated an intense and comprehensive Hg deposition...

  7. Histopathological changes induced by acute toxicity of mercuric chloride on the air-breathing organ (branchial diverticulum) of the life-fish Heteropneustes (= Saccobranchus) fossilis (BLOCH)

    Energy Technology Data Exchange (ETDEWEB)

    Rajan, M.T. (Histochemistry and Histopathology Lab., Dept. of Zoology, Banaras Hindu Univ., Varanasi (India)); Banerjee, T.K. (Histochemistry and Histopathology Lab., Dept. of Zoology, Banaras Hindu Univ., Varanasi (India))

    1993-01-01

    Toxicity induced by 0.3 ppm (96 h LC[sub 50] value) mercuric chloride solution on the histomorphology of the innerlining of the air breathing organ (branchial diverticulum) of Heteropneustes fossilis has been described. The outer cell layers of the epithelial lining show cyclic necrosis leading to shedding with ultimate haemorrhage and drainage of blood into the lumen causing decrease in the number of blood islets. Simultaneously the epithelium regenerates causing hyperplasia of its cells and increased gas diffusion distance impairing normal aerial respiration. Also the number of foldings decreases and the secondary lamella like structures fuse together. This results in smoothening of the inner lining of the air sac. Later reappearance of the blood islets, secondary lamellae and foldings of the inner lining are observed along with the repair of the epithelium. Damage of the repaired inner lining follows again. (orig.)

  8. Implementation of a micro-physical scheme for warm clouds in the meteorological model 'MERCURE': Application to cooling tower plumes and to orographic precipitation

    International Nuclear Information System (INIS)

    Bouzereau, Emmanuel

    2004-01-01

    A two-moment semi-spectral warm micro-physical scheme has been implemented inside the meteorological model 'MERCURE'. A new formulation of the buoyancy flux () is proposed, which is coherent with the corrigendum of Mellor (1977) but differs from Bougeault (1981). The non-precipitating cloud microphysics is validated by comparing the numerical simulations of fifteen cases of cooling tower plumes with data from a measurement campaign in Bugey in 1980. Satisfactory results are obtained on the plumes shape, on the temperature and vertical velocity fields and on the droplets spectrums, although the liquid water contents tend to be overestimated. The precipitating cloud microphysics is tested by reproducing the academical cases of orographic precipitation of Chaumerliac et al. (1987) and Richard and Chaumerliac (1989). The simulations allow a check of the action of different micro-physical terms. (author) [fr

  9. Mercuric oxide poisoning

    Science.gov (United States)

    ... Essentials of Toxicology. 3rd ed. New York, NY: McGraw Hill Medical; 2015:chap 23. Theobald JL, Mycyk ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  10. Study of lead iodide semiconductor crystals doped with silver

    Czech Academy of Sciences Publication Activity Database

    Matuchová, Marie; Žďánský, Karel; Zavadil, Jiří; Maixner, J.; Alexiev, D.; Procházková, Olga

    2006-01-01

    Roč. 9, 1/3 (2006), s. 394-398 ISSN 1369-8001. [DRIP /11./. Beijing, 15.09.2005-19.09.2005] R&D Projects: GA ČR(CZ) GA102/03/0379; GA ČR(CZ) GA102/04/0959; GA AV ČR(CZ) KSK1010104 Institutional research plan: CEZ:AV0Z20670512 Keywords : rare earth compounds * detector circuits * semiconductor technology Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.038, year: 2006

  11. Effect of iodide on glucose oxidation and 32P incorporation into phospholipids stimulated by different agents in dog thyroid slices

    International Nuclear Information System (INIS)

    Tseng, F.Y.; Rani, C.S.; Field, J.B.

    1989-01-01

    Since iodide (I-) inhibits TSH stimulation of cAMP formation, which mediates most of the effects of the hormone, it has been assumed that this accounts for the inhibitory action of iodide on the thyroid. However, TSH stimulation of 32P incorporation into phospholipids and stimulation of thyroid metabolism by other agonists, such as carbachol, phorbol esters, and ionophore A23187, is not cAMP mediated. The present studies examined the effect of iodide on stimulation of glucose oxidation and 32P incorporation into phospholipids by TSH and other agonists to determine if the inhibition of cAMP formation was responsible for the action of iodide. Preincubation of dog thyroid slices for 1 h with iodide (10(-4) M) inhibited TSH-, (Bu)2cAMP-, carbachol-, methylene blue-, 12-O-tetradecanoyl phorbol-13-acetate-, ionophore A23187-, prostaglandin E1-, and cholera toxin-stimulated glucose oxidation. I- also inhibited the stimulation by TSH, 12-O-tetradecanoyl phorbol-13-acetate, carbachol, and ionophore A23187 of 32P incorporation into phospholipids. The inhibition was similar whether iodide was added 2 h before or simultaneously with the agonist. I- itself sometimes stimulated basal glucose oxidation, but had no effect on basal 32P incorporation into phospholipids. The effects of iodide on basal and agonist-stimulated thyroid metabolism were blocked by methimazole (10(-3) M). When dog thyroid slices were preloaded with 32PO4 or [1-14C]glucose, the iodide inhibition of agonist stimulation disappeared, suggesting that the effect of iodide involves the transport process. In conclusion, I- inhibited stimulation of glucose oxidation and 32P incorporation into phospholipids by all agonists, indicating that the effect is independent of the cAMP system and that iodide autoregulation does not only involve this system. Oxidation and organification of iodide are necessary for the inhibition

  12. Radiation detector

    International Nuclear Information System (INIS)

    Conrad, B.; Finkenzeller, J.; Kiiehn, G.; Lichtenberg, W.

    1984-01-01

    In an exemplary embodiment, a flat radiation beam is detected having a common electrode disposed parallel to the beam plane at one side and a common support with a series of individual conductors providing electrodes opposite successive portions of the common electrode and lying in a plane also parallel to the beam plane. The beam may be fan-shaped and the individual electrodes may be aligned with respective ray paths separated by uniform angular increments in the beam plane. The individual conductors and the connection thereof to the exterior of the detector housing may be formed on an insulator which can be folded into a T-shape for leading the supply conductors for alternate individual conductors toward terminals at opposite sides of the chamber

  13. Particle detectors

    CERN Document Server

    Hilke, Hans Jürgen; Joram, Christian; CERN. Geneva

    1991-01-01

    Lecture 5: Detector characteristics: ALEPH Experiment cut through the devices and events - Discuss the principles of the main techniques applied to particle detection ( including front-end electronics), the construction and performance of some of the devices presently in operartion and a few ideas on the future performance. Lecture 4-pt. b Following the Scintillators. Lecture 4-pt. a : Scintillators - Used for: -Timing (TOF, Trigger) - Energy Measurement (Calorimeters) - Tracking (Fibres) Basic scintillation processes- Inorganic Scintillators - Organic Scintil - Discuss the principles of the main techniques applied to particle detection ( including front-end electronics), the construction and performance of some of the devices presently in operation and a fiew ideas on future developpement session 3 - part. b Following Calorimeters lecture 3-pt. a Calorimeters - determine energy E by total absorption of charged or neutral particles - fraction of E is transformed into measurable quantities - try to acheive sig...

  14. Smoke detectors

    International Nuclear Information System (INIS)

    Bryant, J.

    1979-01-01

    An ionization smoke detector consisting of two electrodes defining an ionization chamber permitting entry of smoke, a radioactive source to ionize gas in the chamber and a potential difference applied across the first and second electrodes to cause an ion current to flow is described. The current is affected by entry of smoke. An auxiliary electrode is positioned in the ionization chamber between the first and second electrodes, and it is arranged to maintain or create a potential difference between the first electrode and the auxiliary electrode. The auxiliary electrode may be used for testing or for adjustment of sensitivity. A collector electrode divides the chamber into two regions with the auxiliary electrode in the outer sensing region. (U.K.)

  15. Ionization detector

    International Nuclear Information System (INIS)

    Solomon, E.E.

    1980-01-01

    A safe and reliable apparatus for detecting products of combustion and aerosols in the atmosphere was developed which uses a beta source. It is easy to adjust for optimum performance. The ionization detector comprises a double chamber; one of the chambers is the basic sensing chamber. The sensing chamber is ported to both the secondary chambers to account for slow ambient changes in the atmosphere outside of the chamber. The voltages from the ionization chamber are adjusted with electrodes in each chamber. The ionization chamber contains baffles to direct the air to be sensed as well as an electrostatic screen. A unique electronic circuit provides an inexpensive and reliable means for detecting the signal change which occurs in the ionization chamber. The decision level of the alarm circuit can be adjusted to allow for any desired sensitivity. (D.N.)

  16. New Microporous Polymer Electrolyte Based on Polysiloxane Grafted with Imidazolium Iodide Moieties for DSSC

    Directory of Open Access Journals (Sweden)

    Yan Yang

    2011-01-01

    Full Text Available Two types of polysiloxane grafted with different ratio of imidazolium iodide moieties (IL-SiO2 have been synthesized to develop a micro-porous polymer electrolyte for quasi-solid-state dye-sensitized solar cells. The samples were characterized by 1HNMR, FT-IR spectrum, XRD, TEM and SEM, respectively. Moreover, the ionic conductivity of the electrolytes was measured by electrochemical workstation. Nanostructured polysiloxane containing imidazolium iodide showed excellent compatibility with organic solvent and polymer matrix for its ionic liquid characteristics. Increasing the proportion of imidazolium iodide moieties in polysiloxane improved the electrochemical behavior of the gel polymer electrolyte. A dye-sensitized solar cell with gel polymer electrolyte yielded an open-circuit voltage of 0.70 V, short-circuit current of 11.19 mA cm−2, and the conversion efficiency of 3.61% at 1 sun illumination.

  17. The distribution of radioiodine administrated to pregnant mice and the effect of non radioactive iodide

    International Nuclear Information System (INIS)

    Okui, Toyo; Kobayashi, Satoshi

    1987-01-01

    Radioiodine, 131 I, which has a high fission yield in the nuclear reactor, is easily taken into the human body, accumilating in the thyroid gland, when released to the environment. 131 I was administrated orally to pregnant mice, and its transportation to the tissues, particularly the fetus, was examined closely. And further, the non-radioactive iodide, i.e., KI, was administrated to see its radiation protection effect. The transportation of 131 I to the fetus is the second highest, following the thyroid gland in the mother mouse. This transportation to the fetus becomes the higher, the larger the gestation period at which the 131 I administration is made. The administration of the non-radioactive iodide has large radiation protection effect in the thyroid gland of the mother mouse and of the fetus. But, depending on its concentration, the non-radioactive iodide may conversely increase overall exposure of the fetus. (Mori, K.)

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

    Science.gov (United States)

    Fierro, Stéphane; Comninellis, Christos; Einaga, Yasuaki

    2013-01-15

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

  19. Zingiber officinale and 6-gingerol alleviate liver and kidney dysfunctions and oxidative stress induced by mercuric chloride in male rats: A protective approach.

    Science.gov (United States)

    Joshi, Deepmala; Srivastav, Sunil Kumar; Belemkar, Sateesh; Dixit, Vaibhav A

    2017-07-01

    Mercury toxicity is an emerging problem in the world as its concentration is rising continuously due to increased industrial, medicinal and domestic uses. Exposure to mercury represents a serious challenge to humans and other living biomes. The aim of the present study was to assess the protective effect of natural products as Zingiber officinale extract and its active compound (6-gingerol) against mercuric chloride-induced hepatorenal toxicity and oxidative stress in male rats. Male Sprague-Dawley rats (150±10g, n=6 per group) were administered HgCl 2 (12μmol/kg, ip; once only) the treatment of Zingiber officinale Rosc. extract (ZO: 125mg/kg, po) and 6-gingerol (GG: 50mg/kg, po) for three days after 24h of HgCl 2 administration. Acute HgCl 2 administration altered various biochemical parameters, including transaminases, alkaline phosphatase, lactate dehydrogenase, bilirubin, gamma-glutamyl transferase, triglycerides and cholesterol, urea, creatinine, uric acid and blood urea nitrogen contents with a concomitant decline in protein and albumin concentration in serum. In addition, a significant rise in lipid peroxidation level with concomitant decrease in reduced glutathione content and the antioxidant enzymes activities of superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and glutathione-S-transferase after acute HgCl 2 exposure. Results of the present investigation clearly showed that both treatments as Zingiber officinale extract and 6-gingerol provide protection against acute mercuric chloride-intoxication by preventing oxidative degradation of a biological membrane from metal mediated free radical attacks. Biochemical data were well supported by histopathological findings. In conclusion, natural products may be an ideal choice against oxidative damage induced by mercury poisoning. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  20. Mercury (II) removal by resistant bacterial isolates and mercuric (II) reductase activity in a new strain of Pseudomonas sp. B50A.

    Science.gov (United States)

    Giovanella, Patricia; Cabral, Lucélia; Bento, Fátima Menezes; Gianello, Clesio; Camargo, Flávio Anastácio Oliveira

    2016-01-25

    This study aimed to isolate mercury resistant bacteria, determine the minimum inhibitory concentration for Hg, estimate mercury removal by selected isolates, explore the mer genes, and detect and characterize the activity of the enzyme mercuric (II) reductase produced by a new strain of Pseudomonas sp. B50A. The Hg removal capacity of the isolates was determined by incubating the isolates in Luria Bertani broth and the remaining mercury quantified by atomic absorption spectrophotometry. A PCR reaction was carried out to detect the merA gene and the mercury (II) reductase activity was determined in a spectrophotometer at 340 nm. Eight Gram-negative bacterial isolates were resistant to high mercury concentrations and capable of removing mercury, and of these, five were positive for the gene merA. The isolate Pseudomonas sp. B50A removed 86% of the mercury present in the culture medium and was chosen for further analysis of its enzyme activity. Mercuric (II) reductase activity was detected in the crude extract of this strain. This enzyme showed optimal activity at pH 8 and at temperatures between 37 °C and 45 °C. The ions NH4(+), Ba(2+), Sn(2+), Ni(2+) and Cd(2+) neither inhibited nor stimulated the enzyme activity but it decreased in the presence of the ions Ca(2+), Cu(+) and K(+). The isolate and the enzyme detected were effective in reducing Hg(II) to Hg(0), showing the potential to develop bioremediation technologies and processes to clean-up the environment and waste contaminated with mercury. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Potentiometric sensing of iodide using polymeric membranes of microwave stabilized β-AgI

    International Nuclear Information System (INIS)

    James, Dhanya; Rao, T. Prasada

    2012-01-01

    Highlights: ► Stable β-phase was obtained by post MW irradiation of AgI precipitate. ► Constructed ISEby dispersing stable β-AgI crystals in polyvinyl chloride. ► Designed iodide ISE exhibited wide linear range and fast response. ► Highly selective with selectivity factors less than 10 −6 . ► Successfully applied to natural waters, table salt and human urine samples. - Abstract: A polymer based heterogeneous ion selective electrode (ISE) membrane was fabricated for the potentiometric sensing of iodide. The sensing element used for the preparation of the ISE membrane was microwave stabilized β-AgI. Because microwave energy was found to be beneficial for causing hysteresis at the phase transition temperature of AgI, an attempt has been made to prepare stable and conductive β-AgI crystals by post microwave irradiation under high pressure. A conventionally precipitated AgI based ISE was also fabricated for comparative studies. The β-AgI based ISE could respond to a wide range of iodide concentrations (1 × 10 −8 to 1 M) within 60 s with a detection limit of 10 nM. The ISE gave stable response to iodide ions in a pH range of 2.0–8.0 and was highly selective in the presence of various interfering ions. The performance of the proposed iodide ISE in the analysis of natural and seawater samples was encouraging, and the determination of iodide in table salt and human urine samples was explained using the developed sensor.

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

    International Nuclear Information System (INIS)

    Sun, Zhuyu; Zhang, Chaojie; Zhao, Xiaoyun; Chen, Jing; Zhou, Qi

    2017-01-01

    Highlights: • N-nitrosodimethylamine (NDMA) was effectively decomposed by UV/iodide process. • NDMA was completely converted to nontoxic end products by UV/iodide process. • The photoreductive process was mainly attributed to the attack of hydrated electrons on the photoexcited NDMA. • The elimination of toxic intermediates was greatly enhanced as pH increased, but its effect on NDMA removal was negligible. - Abstract: N-nitrosodimethylamine (NDMA) has aroused extensive concern as a disinfection byproduct due to its high toxicity and elevated concentration levels in water sources. This study investigates the photoreductive decomposition of NDMA by UV/iodide process. The results showed that this process is an effective strategy for the treatment of NDMA with 99.2% NDMA removed within 10 min. The depletion of NDMA by UV/iodide process obeyed pseudo-first-order kinetics with a rate constant (k_1) of 0.60 ± 0.03 min"−"1. Hydrated electrons (e_a_q"−) generated by the UV irradiation of iodide were proven to play a critical role. Dimethylamine (DMA) and nitrite (NO_2"−) were formed as the main intermediate products, which completely converted to formate (HCOO"−), ammonium (NH_4"+) and nitrogen (N_2). Therefore, not only the high efficiencies in NDMA destruction, but the elimination of toxic intermediates make UV/iodide process advantageous. A photoreduction mechanism was proposed: NDMA initially absorbed photons to a photoexcited state, and underwent a cleavage of N−NO bond under the attack of e_a_q"−. The solution pH had little impact on NDMA removal. However, alkaline conditions were more favorable for the elimination of DMA and NO_2"−, thus effectively reducing the secondary pollution.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-05-05

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

  4. Multicompartmental model for iodide, thyroxine, and triiodothyronine metabolism in normal and spontaneously hyperthyroid cats

    Energy Technology Data Exchange (ETDEWEB)

    Hays, M.T.; Broome, M.R.; Turrel, J.M.

    1988-06-01

    A comprehensive multicompartmental kinetic model was developed to account for the distribution and metabolism of simultaneously injected radioactive iodide (iodide*), T3 (T3*), and T4 (T4*) in six normal and seven spontaneously hyperthyroid cats. Data from plasma samples (analyzed by HPLC), urine, feces, and thyroid accumulation were incorporated into the model. The submodels for iodide*, T3*, and T4* all included both a fast and a slow exchange compartment connecting with the plasma compartment. The best-fit iodide* model also included a delay compartment, presumed to be pooling of gastrosalivary secretions. This delay was 62% longer in the hyperthyroid cats than in the euthyroid cats. Unexpectedly, all of the exchange parameters for both T4 and T3 were significantly slowed in hyperthyroidism, possibly because the hyperthyroid cats were older. None of the plasma equivalent volumes of the exchange compartments of iodide*, T3*, or T4* was significantly different in the hyperthyroid cats, although the plasma equivalent volume of the fast T4 exchange compartments were reduced. Secretion of recycled T4* from the thyroid into the plasma T4* compartment was essential to model fit, but its quantity could not be uniquely identified in the absence of multiple thyroid data points. Thyroid secretion of T3* was not detectable. Comparing the fast and slow compartments, there was a shift of T4* deiodination into the fast exchange compartment in hyperthyroidism. Total body mean residence times (MRTs) of iodide* and T3* were not affected by hyperthyroidism, but mean T4* MRT was decreased 23%. Total fractional T4 to T3 conversion was unchanged in hyperthyroidism, although the amount of T3 produced by this route was increased nearly 5-fold because of higher concentrations of donor stable T4.

  5. Multicompartmental model for iodide, thyroxine, and triiodothyronine metabolism in normal and spontaneously hyperthyroid cats

    International Nuclear Information System (INIS)

    Hays, M.T.; Broome, M.R.; Turrel, J.M.

    1988-01-01

    A comprehensive multicompartmental kinetic model was developed to account for the distribution and metabolism of simultaneously injected radioactive iodide (iodide*), T3 (T3*), and T4 (T4*) in six normal and seven spontaneously hyperthyroid cats. Data from plasma samples (analyzed by HPLC), urine, feces, and thyroid accumulation were incorporated into the model. The submodels for iodide*, T3*, and T4* all included both a fast and a slow exchange compartment connecting with the plasma compartment. The best-fit iodide* model also included a delay compartment, presumed to be pooling of gastrosalivary secretions. This delay was 62% longer in the hyperthyroid cats than in the euthyroid cats. Unexpectedly, all of the exchange parameters for both T4 and T3 were significantly slowed in hyperthyroidism, possibly because the hyperthyroid cats were older. None of the plasma equivalent volumes of the exchange compartments of iodide*, T3*, or T4* was significantly different in the hyperthyroid cats, although the plasma equivalent volume of the fast T4 exchange compartments were reduced. Secretion of recycled T4* from the thyroid into the plasma T4* compartment was essential to model fit, but its quantity could not be uniquely identified in the absence of multiple thyroid data points. Thyroid secretion of T3* was not detectable. Comparing the fast and slow compartments, there was a shift of T4* deiodination into the fast exchange compartment in hyperthyroidism. Total body mean residence times (MRTs) of iodide* and T3* were not affected by hyperthyroidism, but mean T4* MRT was decreased 23%. Total fractional T4 to T3 conversion was unchanged in hyperthyroidism, although the amount of T3 produced by this route was increased nearly 5-fold because of higher concentrations of donor stable T4

  6. Silicon radiation detectors

    International Nuclear Information System (INIS)

    Lutz, G.

    1995-01-01

    An introduction to and an overview of function principles and properties of semiconductor radiation detectors is attempted. The paper is addressed to people interested in detector development but not already experts in the field of semiconductor detectors. (orig.)

  7. Theoretical and experimental investigations on the behaviour of iodine during severe accidents: organic iodide, iodine/silver reaction, iodine/iron reaction. Pt. 4: organic iodide. Final report

    International Nuclear Information System (INIS)

    Hellmann, S.; Greger, G.U.; Funke, F.; Bleier, A.; Zeeh, W.

    1995-11-01

    Analysis of the consequences of severe accidents in nuclear power plants requires knowledge of the behaviour of radionuclides relevant from the radiological viewpoint. The role played by radioiodine is particularly important. In the current modelling of iodine behaviour the heterogeneous formation of organic iodide is not adequately taken into consideration owing to a lack of data or insufficient accuracy of data. This project is intended to eliminate some gaps in critical areas. This final report, part 4, describes the tests carried out in the two relevant areas - heterogeneous formation of organic coatings in the gas phase (containment atmosphere) - heterogeneous formation of organic iodide at organic coatings in aqueous phase (containment sump). Moreover, modelling suggestions how to include the resulting knowledge in the iodine accident behaviour code IMPAIR are given. (orig.) [de

  8. One column method to prepare 11C-labelled methyl iodide

    International Nuclear Information System (INIS)

    Kovacs, Z.; Priboczki, E.

    1999-01-01

    A new method in which the [ 11 C]methyl iodide is prepared on one alumina column is presented. A high specific surface alumina column, previously impregnated with lithium aluminium hydride solution, was used for direct trapping from the target gas and reduction into radiocomplex. The complex was then reacted on this column with HI to form [ 11 C]methyl iodide. The use of one alumina column, instead of a freezing trap, reaction vessel and separate unit for iodination, simplifies the apparatus, shortens the synthesis time and is well suitable for automation. (K.A.)

  9. Uptake of Iodide From Water in Atlantic Halibut Larvae (Hippoglossus Hippoglossus L.)

    DEFF Research Database (Denmark)

    Moren, Mari; Sloth, Jens Jørgen; Hamre, Kristin

    2008-01-01

    The natural diet of marine fish larvae, copepods, contain 60-350 mg I kg(-1), while live feed used in commercial hatcheries have iodine concentrations in the range of 1 mg kg(-1). Seawater is also considered to be an important source of iodine for marine fish. The question asked in this study is ......M. The uptake was partly blocked by perchlorate (ClO3-) which is a known inhibitor of the sodium iodide symporter. This indicates that the Atlantic halibut larvae accumulate iodide through both specific and non-specific uptake pathways....

  10. Optical power limiting and transmitting properties of cadmium iodide single crystals: Temperature dependence

    Energy Technology Data Exchange (ETDEWEB)

    Miah, M. Idrish, E-mail: m.miah@griffith.edu.a [Nanoscale Science and Technology Centre, Griffith University, Nathan, Brisbane, QLD 4111 (Australia)] [Biomolecular and Physical Sciences, Griffith University, Nathan, Brisbane, QLD 4111 (Australia)] [Department of Physics, University of Chittagong, Chittagong 4331 (Bangladesh)

    2009-09-14

    Optical limiting properties of the single crystals of cadmium iodide are investigated using ns laser pulses. It is found that the transmissions in the crystals increase with increasing temperature. However, they limit the transmissions at high input powers. The limiting power is found to be higher at higher temperature. From the measured transmission data, the photon absorption coefficients are estimated. The temperature dependence of the coefficients shows a decrease in magnitude with increasing temperature. This might be due to the temperature-dependent bandgap shift of the material. The results demonstrate that the cadmium iodide single crystals are promising materials for applications in optical power limiting devices.

  11. Optical power limiting and transmitting properties of cadmium iodide single crystals: Temperature dependence

    International Nuclear Information System (INIS)

    Miah, M. Idrish

    2009-01-01

    Optical limiting properties of the single crystals of cadmium iodide are investigated using ns laser pulses. It is found that the transmissions in the crystals increase with increasing temperature. However, they limit the transmissions at high input powers. The limiting power is found to be higher at higher temperature. From the measured transmission data, the photon absorption coefficients are estimated. The temperature dependence of the coefficients shows a decrease in magnitude with increasing temperature. This might be due to the temperature-dependent bandgap shift of the material. The results demonstrate that the cadmium iodide single crystals are promising materials for applications in optical power limiting devices.

  12. Study of adsorption properties of impregnated charcoal for airborne iodine and methyl iodide

    International Nuclear Information System (INIS)

    Qi-dong, L.; Sui-yuang, H.

    1985-01-01

    The adsorption characteristics of airborne radioiodine and methyl iodide on impregnated charcoal were investigated. The activated charcoal tested was made from home-made oil-palm shells, and KI and TEDA were used as impregnants. A new technique was used to plot the dynamic partial adsorption isotherm at challenge concentrations (concentration range of iodine: 1-20 ppm v/v). Some adsorption properties of the impregnated charcoal were estimated with the dynamic partial adsorption isotherm. The dependences of the adsorption capacity and penetration behavior for airborne iodine and methyl iodide on the ambient conditions (temperature, relative humidity, and superficial velocity) were studied

  13. Studying the iodine leaching from the compositions based on epoxide resin and lead iodide

    International Nuclear Information System (INIS)

    Kalinin, N.N.; Elizarova, A.N.

    1988-01-01

    When studying iodine leaching, the possibility to use solid compositions, produced by incorporation of dry powdered lead iodide and its aqueous suspension into epoxide resin for long-term immobilization of iodine-129 under conditions of monitored storage, is evaluated. Analysis of the results obtained has shown that leaching rate in the first 4 days has the maximum value and constitutes (4.2 - 2700.0) x 10 -6 cm/day. Then the process of leaching is determined by diffusion mechanism. For samples, prepared by wet lead iodide incorporation the rate of leaching is higher than that of the corresponding samples prepared by dry compound incorporation

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

    Directory of Open Access Journals (Sweden)

    Siou-Wei Ou

    2012-02-01

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

  15. 3.2. Antibacterial activity of ethynyl-piperidol polymers and their three-iodides

    International Nuclear Information System (INIS)

    Khalikov, D.Kh.

    2012-01-01

    The antibacterial activity of ethynyl-piperidol polymers and their three-iodides was studied. The antibacterial films based on iodine with copolymer N-vinyl pyrrolidone, methylmethacrylate and butyl acrylate were obtained. It was found that samples containing 9-10% of iodine in copolymer have the antiseptic properties. The antibacterial properties of three-iodides grafted nitrogen containing polymers with cellulose fibrous materials were considered. The membrane-active properties of homo- and copolymers of ethynyl piperidol derivatives were considered as well.

  16. Method for removing radioactive iodine and radioactive organic iodides from effluent gases

    International Nuclear Information System (INIS)

    1975-01-01

    A method and composition for removing radioactive and organic iodides from an 131 I-containing off-gas stream is provided. The composition for removal by adsorption is a ceramic material with a surface area of from about 5 m 2 /g to about 250 m 2 /g impregnated with a metallic salt. The method for removing the iodine or iodide is accomplished by passing the off-gas stream over the ceramic material impregnated with the metallic salt. It finds special application in air filters for nuclear power plants

  17. Sorption of microamount of colloidal silver iodide on hydrated iron(III) oxide

    International Nuclear Information System (INIS)

    Kepak, F.; Nova, J.

    1975-01-01

    Sorption of a microamount of colloidal silver iodide labelled with 131 I on hydrated iron/III/ oxide suspension was studied. The sorption dependence upon pH, sorbent amount, and inert electrolyte concentration has revealed that sorption of silver iodide reaches no more than 63%. The sorption lasted one hour during which the maximum value was reached. Desorption time was one hour, as well. Except for measuring the sorption dependence on pH, the sorption pH was 7.0, temperature 24+-2 0 C. (F.G.)

  18. 76 FR 16770 - Petition To Suspend and Cancel All Registrations for the Soil Fumigant Iodomethane (Methyl Iodide...

    Science.gov (United States)

    2011-03-25

    ... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2010-0541; FRL-8841-7] Petition To Suspend and Cancel... Earthjustice requesting that all uses of iodomethane (methyl iodide) be suspended and cancelled. The Agency is... uses of iodomethane (methyl iodide) be suspended and cancelled. The Agency is posting this petition for...

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

    Science.gov (United States)

    Nikolaychuk, Pavel Anatolyevich; Kuvaeva, Alyona Olegovna

    2016-01-01

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

  20. Calibration of detector efficiency of neutron detector

    International Nuclear Information System (INIS)

    Guo Hongsheng; He Xijun; Xu Rongkun; Peng Taiping

    2001-01-01

    BF 3 neutron detector has been set up. Detector efficiency is calibrated by associated particle technique. It is about 3.17 x 10 -4 (1 +- 18%). Neutron yield of neutron generator per pulse (10 7 /pulse) is measured by using the detector

  1. Early effects of external gamma irradiation on iodide metabolism in rat thyroid

    International Nuclear Information System (INIS)

    Niatsetskaya, Z.; Nadolnik, L.

    2006-01-01

    Full text of publication follows: The exposure of the thyroid gland to therapeutic doses of external gamma irradiation is frequently associated with thyroid dysfunction. Although late irradiation effects are well documented, little is still known about the early functional alterations in the thyroid subjected to radiation therapy. The aim of this study was to examine the early effect of single external gamma irradiation on iodide metabolism in the thyroid. The Wistar female rats were irradiated using a 60 Co installation with a constant capacity of 0.64 Gy/min. The doses used were 0.25, 0.5, 1, 2, 5 Gy. The animals were sacrificed after 24 hours following the irradiation. T he thyroid organ culture was cultivated during 24 h and than was irradiated with a single dose of 5 Gy. The thyroid tissue was assayed for thyro-peroxidase activity and concentrations of total, free and protein -binding iodide. It was shown that the 0.25 Gy irradiation depressed thyroid iodide uptake, which was manifested in decreasing total iodide by 25%. The same tendency was observed after the 0.5 Gy irradiation. In the 1, 2, 5 Gy groups, the concentrations of total and free iodide increased by 26 -34% and 50-68%, accordingly. The level of protein-binding iodide in these groups was within the control values. However, protein-binding/total iodide and protein binding/ free iodide ratios decreased by 17 -41%, suggesting inhibition of thyroglobulin iodination. Thyro-peroxidase (T.P.O.) plays a key role in thyroid hormone synthesis by catalyzing both the iodination of thyroglobulin and the coupling some of the iodo-tyrosyl residues. After 24 hours on irradiation, a 31.5-54% dose-dependent inhibition of T.P.O. activity was shown in the 1, 2 and 5 Gy groups. The irradiation of the rat thyroid organ culture with a single dose of 5 Gy also led to significant inhibition of T.P.O. by 56.91% after 2 hours. We compared the enzyme kinetics of thyro-peroxidase from thyroid microsomal fraction control and

  2. Position detector

    International Nuclear Information System (INIS)

    Hayakawa, Toshifumi.

    1985-01-01

    Purpose: To enable to detect the position of an moving object in a control rod position detector, stably in a digital manner at a high accuracy and free from the undesired effects of circumstantial conditions such as the reactor temperature. Constitution: Coils connected in parallel with each other are disposed along the passage of a moving object and variable resistors and relays are connected in series with each of the coils respectively. Light emitting diodes is connected in series with the contacts of the respective relays. The resistance value of the variable resistors are adjusted depending on the changes in the circumstantial conditions and temperature distribution upon carrying out the positional detection. When the object is inserted into a coils, the relevant relay is deenergized, by which the relay contacts are closed to light up the diode. In the same manner, as the object is successively inserted into the coils, the diodes are lighted-up successively thereby enabling highly accurate and stable positional detection in a digital manner, free from the undesired effects of the circumstantial conditions. (Horiuchi, T.)

  3. MUON DETECTOR

    CERN Multimedia

    F. Gasparini

    DT As announced in the previous Bulletin MU DT completed the installation of the vertical chambers of barrel wheels 0, +1 and +2. 242 DT and RPC stations are now installed in the negative barrel wheels. The missing 8 (4 in YB-1 and 4 in YB-2) chambers can be installed only after the lowering of the two wheels into the UX cavern, which is planned for the last quarter of the year. Cabling on the surface of the negative wheels was finished in May after some difficulties with RPC cables. The next step was to begin the final commissioning of the wheels with the final trigger and readout electronics. Priority was giv¬en to YB0 in order to check everything before the chambers were covered by cables and services of the inner detectors. Commissioning is not easy since it requires both activity on the central and positive wheels underground, as well as on the negative wheels still on the surface. The DT community is requested to commission the negative wheels on surface to cope with a possible lack of time a...

  4. Detector simulation needs for detector designers

    International Nuclear Information System (INIS)

    Hanson, G.G.

    1987-11-01

    Computer simulation of the components of SSC detectors and of the complete detectors will be very important for the designs of the detectors. The ratio of events from interesting physics to events from background processes is very low, so detailed understanding of detector response to the backgrounds is needed. Any large detector for the SSC will be very complex and expensive and every effort must be made to design detectors which will have excellent performance and will not have to undergo major rebuilding. Some areas in which computer simulation is particularly needed are pattern recognition in tracking detectors and development of shower simulation code which can be trusted as an aid in the design and optimization of calorimeters, including their electron identification performance. Existing codes require too much computer time to be practical and need to be compared with test beam data at energies of several hundred GeV. Computer simulation of the processing of the data, including electronics response to the signals from the detector components, processing of the data by microprocessors on the detector, the trigger, and data acquisition will be required. In this report we discuss the detector simulation needs for detector designers

  5. Radioiodine source term and its potential impact on the use of potassium iodide

    International Nuclear Information System (INIS)

    Malinauskas, A.P.

    1982-01-01

    Information is presented concerning chemical forms of fission product iodine in the primary circuit; chemical forms of fission product iodine in the containment building; summary of iodine chemistry in light water reactor accidents; and impact of the radiodine source term on the potassium iodide issue

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

    NARCIS (Netherlands)

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

    2016-01-01

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

  7. Expedient Method for Samarium(II) Iodide Preparation Utilizing a Flow Approach

    Czech Academy of Sciences Publication Activity Database

    Voltrová, Svatava; Šrogl, Jiří

    2013-01-01

    Roč. 24, č. 3 (2013), s. 394-396 ISSN 0936-5214 R&D Projects: GA MŠk LH12013 Institutional support: RVO:61388963 Keywords : flow * samarium * iodide * reduction Subject RIV: CC - Organic Chemistry Impact factor: 2.463, year: 2013

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

    Science.gov (United States)

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

    2015-11-01

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

  9. Electron stimulated reactions of methyl iodide coadsorbed with amorphous solid water

    International Nuclear Information System (INIS)

    Perry, C. C.; Faradzhev, N. S.; Madey, T. E.; Fairbrother, D. H.

    2007-01-01

    The electron stimulated reactions of methyl iodide (MeI) adsorbed on and suspended within amorphous solid water (ice) were studied using a combination of postirradiation temperature programmed desorption and reflection absorption infrared spectroscopy. For MeI adsorbed on top of amorphous solid water (ice), electron beam irradiation is responsible for both structural and chemical transformations within the overlayer. Electron stimulated reactions of MeI result principally in the formation of methyl radicals and solvated iodide anions. The cross section for electron stimulated decomposition of MeI is comparable to the gas phase value and is only weakly dependent upon the local environment. For both adsorbed MeI and suspended MeI, reactions of methyl radicals within MeI clusters lead to the formation of ethane, ethyl iodide, and diiodomethane. In contrast, reactions between the products of methyl iodide and water dissociation are responsible for the formation of methanol and carbon dioxide. Methane, formed as a result of reactions between methyl radicals and either parent MeI molecules or hydrogen atoms, is also observed. The product distribution is found to depend on the film's initial chemical composition as well as the electron fluence. Results from this study highlight the similarities in the carbon-containing products formed when monohalomethanes coadsorbed with amorphous solid water are irradiated by either electrons or photons

  10. Continuous monitoring of methyl iodide purity and content in the gas feeding the trapping pilot plant

    International Nuclear Information System (INIS)

    Charrier, G.

    1988-01-01

    An analysis method is developed for inspection of solid traps for gaseous iodine. Methyl iodide injected in the traps is determined by gas chromatography. Contents of 50 ppm in volume are measured. Labelling with iodine 123 allows a better sensitivity, 4 refs, 5 figs, 6 tables [fr

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

    LENUS (Irish Health Repository)

    Ryan, James

    2011-01-01

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

  12. Silver iodide reduction in aqueous solution: application to iodine enhanced separation during spent nuclear fuels reprocessing

    International Nuclear Information System (INIS)

    Badie, Jerome

    2002-01-01

    Silver iodide is a key-compound in nuclear chemistry either in accidental conditions or during the reprocessing of spent nuclear fuel. In that case, the major part of iodine is released in molecular form into the gaseous phase at the time of dissolution in nitric acid. In French reprocessing plants, iodine is trapped in the dissolver off-gas treatment unit by two successive steps: the first consists in absorption by scrubbing with a caustic soda solution and in the second, residual iodine is removed from the gaseous stream before the stack by chemisorption on mineral porous traps made up of beds of amorphous silica or alumina porous balls impregnated with silver nitrate. Reactions of iodine species with the impregnant are assumed to lead to silver iodide and silver iodate. Enhanced separation policy would make necessary to recover iodine from the filters by silver iodide dissolution during a reducing treatment. After a brief silver-iodine chemical bibliographic review, the possible reagents listed in the literature were studied. The choice has been made to use ascorbic acid and hydroxylamine. An experimental work on silver iodide reduction by this two compounds allowed us to determinate reaction products, stoichiometry and kinetics parameters. Finally, the process has been initiated on stable iodine loaded filters samples. (author) [fr

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

    NARCIS (Netherlands)

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

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

  14. Gamma-ray radiolysis of methyl iodide in air, in presence of water vapor

    International Nuclear Information System (INIS)

    Aubert, F.

    2002-03-01

    This work aims at modelling the processes involved in gamma-radiolysis of methyl iodide diluted in air in presence of steam. It is to determine quantitative and qualitative information, to quantify the importance of the organic iodides destruction in case of a nuclear reactor accident. The main data for radiochemistry and iodine compounds (I x O y and INO x ) formation were reviewed and analysed. Literature data about air products radiolysis reactivity towards I 2 and CH 3 I were used to develop a mechanistic model for methyl iodide destruction in the gas phase under gamma irradiation. An ab initio study was realised for a better understanding of atomic nitrogen ( 4 S and 2 D) reactivity towards CH 3 I. The model was tested on the available experimental data and constitute a way to investigate the main processus involved in methyl iodide destruction. For the low CH 3 I concentrations, about 10 -7 - 10 -8 mol.dm -3 , N and e - are mainly responsible for the destruction. I 2 O 4 (highest iodine oxide in the model) and IONO 2 are the main resulting iodinated' compounds. (author)

  15. Iodide-induced thyrotoxicosis in a thyroidectomized patient with metastatic thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Yoshinari, M.; Tokuyama, T.; Okamura, K.; Sato, K.; Kusuda, K.; Fujishima, M.

    1988-04-15

    An unusual case of iodide-induced thyrotoxicosis is documented in this article. The patient was a 64-year-old euthyroid man with acromegaly. He also had multiple follicular and papillary thyroid carcinomas with a metastatic lesion in the lumbar vertebrae. After a total thyroidectomy, he became slightly hypothyroid, and the lumbar lesion began to incorporate /sup 131/I by scintigraphy. When an iodine-containing contrast medium happened to be injected, a transient increase of serum thyroid hormone level was observed. After complete thyroid ablation with 83 mCi of /sup 131/I, the oral administration of 100 mg of potassium iodide for 7 days induced a prominent increase of serum thyroid hormone level. These findings indicated that the metastatic thyroid carcinoma could produce excess thyroid hormone insofar as a sufficient amount of iodide was given. Although this is the first report of such a case, iodide-induced thyrotoxicosis may not be rare in patients with thyroid carcinomas because the Wolff-Chaikoff effect is thought to be lost, and the organic iodinating activity and lysosomal protease activity are well-preserved.

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

    NARCIS (Netherlands)

    Kamminga, Machteld E; De Wijs, Gilles; Havenith, Remco W A; Blake, Graeme R; Palstra, Thomas T M

    2017-01-01

    We use a layered solution crystal growth method to synthesize high-quality single crystals of two different benzylammonium lead iodide perovskite-like organic/inorganic hybrids. The well-known (C6H5CH2NH3)(2)PbI4 phase is obtained in the form of bright orange platelets, with a structure comprised of

  17. Monochloramine determination using NN diethyl-p-phenylene-diamine. Influence of iodide traces

    International Nuclear Information System (INIS)

    Fiquet, J.M.

    1980-09-01

    When determining ''D.P.D.'' free oxidizers, the monochloramine interfers in particular for iodide levels analogous to those likely to be found in sea water. This is not so for iodate. The zero time extrapolation of the change in colour curve is one method that enables the method to be made more selective [fr

  18. Solution enthalpy of potassium iodide in furfural and its mixtures with dimethylsulfoxide

    International Nuclear Information System (INIS)

    Vlasenko, K.K.; Belov, A.A.; Vorob'ev, A.F.

    1986-01-01

    Solution enthalpy of potassium iodide in furfural-dimethylsulfoxide mixtures at 298.15 K and furfural concentration 17.3-100% are determined experimentally. K + and I - ion solvate shell composition, which in the general case doesn't correspond to the mixed solvent composition, is calculated

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

    NARCIS (Netherlands)

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

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

  20. Kinetic modeling of the purging of activated carbon after short term methyl iodide loading

    International Nuclear Information System (INIS)

    Friedrich, V.; Lux, I.

    1991-01-01

    A bimolecular reaction model containing the physico-chemical parameters of the adsorption and desorption was developed earlier to describe the kinetics of methyl iodide retention by activated carbon adsorber. Both theoretical model and experimental investigations postulated constant upstream methyl iodide concentration till the maximum break-through. The work reported here includes the extension of the theoretical model to the general case when the concentration of the challenging gas may change in time. The effect of short term loading followed by purging with air, and an impulse-like increase in upstream gas concentration has been simulated. The case of short term loading and subsequent purging has been experimentally studied to validate the model. The investigations were carried out on non-impregnated activated carbon. A 4 cm deep carbon bed had been challenged by methyl iodide for 30, 90, 120 and 180 min and then purged with air, downstream methyl iodide concentration had been measured continuously. The main characteristics of the observed downstream concentration curves (time and slope of break-through, time and amplitude of maximum values) showed acceptable agreement with those predicted by the model

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

    NARCIS (Netherlands)

    Peverelli, K.J.

    1979-01-01

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

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

    DEFF Research Database (Denmark)

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

    2002-01-01

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

  3. Iodide-induced thyrotoxicosis in a thyroidectomized patient with metastatic thyroid carcinoma

    International Nuclear Information System (INIS)

    Yoshinari, M.; Tokuyama, T.; Okamura, K.; Sato, K.; Kusuda, K.; Fujishima, M.

    1988-01-01

    An unusual case of iodide-induced thyrotoxicosis is documented in this article. The patient was a 64-year-old euthyroid man with acromegaly. He also had multiple follicular and papillary thyroid carcinomas with a metastatic lesion in the lumbar vertebrae. After a total thyroidectomy, he became slightly hypothyroid, and the lumbar lesion began to incorporate 131 I by scintigraphy. When an iodine-containing contrast medium happened to be injected, a transient increase of serum thyroid hormone level was observed. After complete thyroid ablation with 83 mCi of 131 I, the oral administration of 100 mg of potassium iodide for 7 days induced a prominent increase of serum thyroid hormone level. These findings indicated that the metastatic thyroid carcinoma could produce excess thyroid hormone insofar as a sufficient amount of iodide was given. Although this is the first report of such a case, iodide-induced thyrotoxicosis may not be rare in patients with thyroid carcinomas because the Wolff-Chaikoff effect is thought to be lost, and the organic iodinating activity and lysosomal protease activity are well-preserved

  4. Sensitive determination of iodide in the presence of large quantities of chloride

    International Nuclear Information System (INIS)

    Hainberger, L.; Lenzi, E.

    1982-01-01

    A determination of iodide with catalytic oxidation of p-phenetidine is described. A dye is formed with a maximum of absorption at 490 nm. The law of Lambert-Beer is obeyed between 0.6 and 2.2 ppm. Some of the interferents are examined. (Author)

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

    National Research Council Canada - National Science Library

    Benford, James

    1998-01-01

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

  6. Iodide and iodate sodalites for the long-term storage of iodine-129

    International Nuclear Information System (INIS)

    Strachan, D.M.; Babad, H.

    1979-01-01

    There exist several proposals for the storage of 129 I. None of these propose the use of a mineral with demonstrated geologic stability. The work described in this paper has identified the minerals iodide and iodate sodalites [Na 8 (AlSiO 4 ) 6 I 2 /(IO 3 ) 2 ] as good candidates for the long-term storage of 129 I. 4 tables

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

    NARCIS (Netherlands)

    Hoven, van den J.J.

    1984-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-05-15

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

  9. The GRANDE detector

    International Nuclear Information System (INIS)

    Adams, A.; Bond, R.; Coleman, L.; Rollefson, A.; Wold, D.; Bratton, C.B.; Gurr, H.; Kropp, W.; Nelson, M.; Price, L.R.; Reines, F.; Schultz, J.; Sobel, H.; Svoboda, R.; Yodh, G.; Burnett, T.; Chaloupka, V.; Wilkes, R.J.; Cherry, M.; Ellison, S.B.; Guzik, T.G.; Wefel, J.; Gaidos, J.; Loeffler, F.; Sembroski, G.; Wilson, C.; Goodman, J.; Haines, T.J.; Kielczewska, D.; Lane, C.; Steinberg, R.; Lieber, M.; Nagle, D.; Potter, M.; Tripp, R.

    1990-01-01

    In this paper we present a detector facility which meets the requirements outlined above for a next-generation instrument. GRANDE (Gamma Ray and Neutrino DEtector) is an imaging, water Cerenkov detector, which combines in one facility an extensive air shower array and a high-energy neutrino detector. (orig.)

  10. Spiral silicon drift detectors

    International Nuclear Information System (INIS)

    Rehak, P.; Gatti, E.; Longoni, A.; Sampietro, M.; Holl, P.; Lutz, G.; Kemmer, J.; Prechtel, U.; Ziemann, T.

    1988-01-01

    An advanced large area silicon photodiode (and x-ray detector), called Spiral Drift Detector, was designed, produced and tested. The Spiral Detector belongs to the family of silicon drift detectors and is an improvement of the well known Cylindrical Drift Detector. In both detectors, signal electrons created in silicon by fast charged particles or photons are drifting toward a practically point-like collection anode. The capacitance of the anode is therefore kept at the minimum (0.1pF). The concentric rings of the cylindrical detector are replaced by a continuous spiral in the new detector. The spiral geometry detector design leads to a decrease of the detector leakage current. In the spiral detector all electrons generated at the silicon-silicon oxide interface are collected on a guard sink rather than contributing to the detector leakage current. The decrease of the leakage current reduces the parallel noise of the detector. This decrease of the leakage current and the very small capacities of the detector anode with a capacitively matched preamplifier may improve the energy resolution of Spiral Drift Detectors operating at room temperature down to about 50 electrons rms. This resolution is in the range attainable at present only by cooled semiconductor detectors. 5 refs., 10 figs

  11. Performance of iodide vapour absorption in the venturi scrubber working in self-priming mode

    International Nuclear Information System (INIS)

    Zhou, Yanmin; Sun, Zhongning; Gu, Haifeng; Miao, Zhuang

    2016-01-01

    Highlights: • The absorption performance for iodide vapour was studied under different conditions. • A mathematical model was developed to describe the iodide absorption process. • The venturi scrubber can ensure absorption efficiiency and reduce pressure loss. - Abstract: The self-priming venturi scrubber is the key component of filtered containment venting systems for the removal of radioactive products during severe accidents in nuclear power plants. This paper is focused on the absorption performance of iodide vapour in the venturi scrubber, based on experiment and mathematical calculation. The results indicate that the absorption efficiency is closely related to solution flow rate, gas flow rate and temperature, but is not sensitive to iodide inlet concentration. When solution flow rate is low, the absorption efficiency increases rapidly with increasing the solution flow rate, and when the solution is excessive, the absorption efficiency remains around 99% stably; the influence of gas flow rate on absorption efficiency is mainly reflected in the variation of gas and liquid contacting time; when the solution flow rate is low, the increase of gas flow rate will led to an obvious decrease in absorption efficiency; temperature is not important when gas flow rate in constant but becomes effective for improving the absorption efficiency when gas velocity is constant. The proposed mathematical model can predict the iodide absorption process well in the range of experimental conditions. Especially, in the condition of lower gas flow rate and higher solution flow rate, the prediction accuracy is more satisfactory; however the accuracy of prediction will decrease at higher gas flow rates and lower solution flow rates because of neglecting the transverse exchange between gas and liquid phase.

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

    Science.gov (United States)

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

    2013-03-01

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

  13. A new detector array for charged particle spectroscopy

    CERN Document Server

    Cowin, R L; Chappell, S P G; Clarke, N M; Freer, M; Fulton, B R; Cunningham, R A; Curtis, N; Dillon, G; Lilley, J; Jones, C D; Lee, P; Rae, W D M

    1999-01-01

    A compact and highly segmented detector array consisting of 44 gas-silicon-caesium iodide, position sensitive, particle identification detector telescopes and up to 10 position-sensitive, silicon strip detectors has been constructed for the study of light-ion-heavy-ion reactions including cluster break-up in the energy range 5-15 MeV/nucleon. The detectors are housed in a purpose built vacuum chamber. The telescopes are placed in fixed positions, covering the forward hemisphere from 3 to 30 deg. in the laboratory with the target placed at 535 mm from the front of the telescopes or 6-52 deg. with the target placed at 215 mm. The strip detectors are placed in any of 30 fixed positions in the forward hemisphere. For 85 MeV sup 1 sup 2 C ions the telescope energy resolution (gas plus silicon) is 345 keV with an angular resolution of 0.03 deg. . Using the gas-silicon section ions with Z up to 21 can be identified. For ions that pass through the silicon isotopic identification is achieved using the silicon-CsI comb...

  14. Proceedings of the symposium on RHIC detector R&D

    Energy Technology Data Exchange (ETDEWEB)

    Makdisi, Y.; Stevens, A.J. [eds.

    1991-12-31

    This report contains papers on the following topics: Development of Analog Memories for RHIC Detector Front-end Electronic Systems; Monolithic Circuit Development for RHIC at Oak Ridge National Laboratory; Highly Integrated Electronics for the STAR TPC; Monolithic Readout Circuits for RHIC; New Methods for Trigger Electronics Development; Neurocomputing methods for Pattern Recognition in Nuclear Physics; The Development of a Silicon Multiplicity Detector System; The Vertex Detector for the Lepton/Photon Collaboration; Simulations of Silicon Vertex Tracker for STAR Experiment at RHIC; Calorimeter/Absorber Optimization for a RHIC Dimuon Experiment (RD-10 Project); Applications of the LAHET simulation Code to Relativistic Heavy Ion Detectors; Highly Segmented, High Resolution Time-of-Flight System; Research and Development on a Sub 100 Picosecond Time-of-Flight System Based on Silicon Avalance Diodes; Behavior of TPC`s in a High Particle Flux Environment; Generic R&D on Undoped Cesium Iodide and Lead Fluoride; and A Transition Radiation Detector for RHIC Featuring Accurate Tracking and dE/dx Particle Identification. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  15. Crystal surface analysis using matrix textural features classified by a Probabilistic Neural Network

    International Nuclear Information System (INIS)

    Sawyer, C.R.; Quach, V.T.; Nason, D.; van den Berg, L.

    1991-01-01

    A system is under development in which surface quality of a growing bulk mercuric iodide crystal is monitored by video camera at regular intervals for early detection of growth irregularities. Mercuric iodide single crystals are employed in radiation detectors. A microcomputer system is used for image capture and processing. The digitized image is divided into multiple overlappings subimage and features are extracted from each subimage based on statistical measures of the gray tone distribution, according to the method of Haralick [1]. Twenty parameters are derived from each subimage and presented to a Probabilistic Neural Network (PNN) [2] for classification. This number of parameters was found to be optimal for the system. The PNN is a hierarchical, feed-forward network that can be rapidly reconfigured as additional training data become available. Training data is gathered by reviewing digital images of many crystals during their growth cycle and compiling two sets of images, those with and without irregularities. 6 refs., 4 figs

  16. Solid state detector design

    International Nuclear Information System (INIS)

    Gunarwan Prayitno; Ahmad Rifai

    2010-01-01

    Much has been charged particle detector radiation detector made by the industry, especially those engaged in the development of detection equipment and components. The development and further research will be made solid state detector with silicon material. To be able to detect charged particles (radiation), required the processing of silicon material into the detector material. The method used to make silicon detector material is a lithium evaporations. Having formed an intrinsic region contactor installation process, and with testing. (author)

  17. Detector placement optimization for cargo containers using deterministic adjoint transport examination for SNM detection

    International Nuclear Information System (INIS)

    McLaughlin, Trevor D.; Sjoden, Glenn E.; Manalo, Kevin L.

    2011-01-01

    With growing concerns over port security and the potential for illicit trafficking of SNM through portable cargo shipping containers, efforts are ongoing to reduce the threat via container monitoring. This paper focuses on answering an important question of how many detectors are necessary for adequate coverage of a cargo container considering the detection of neutrons and gamma rays. Deterministic adjoint transport calculations are performed with compressed helium- 3 polyethylene moderated neutron detectors and sodium activated cesium-iodide gamma-ray scintillation detectors on partial and full container models. Results indicate that the detector capability is dependent on source strength and potential shielding. Using a surrogate weapons grade plutonium leakage source, it was determined that for a 20 foot ISO container, five neutron detectors and three gamma detectors are necessary for adequate coverage. While a large CsI(Na) gamma detector has the potential to monitor the entire height of the container for SNM, the He-3 neutron detector is limited to roughly 1.25 m in depth. Detector blind spots are unavoidable inside the container volume unless additional measures are taken for adequate coverage. (author)

  18. Spacelab-3 (STS-51B) Onboard Photograph

    Science.gov (United States)

    1985-01-01

    The primary purpose of the Spacelab-3 mission was to conduct materials science experiments in a stable low-gravity environment. In addition, the crew performed research in life sciences, fluid mechanics, atmospheric science, and astronomy. Spacelab-3 was equipped with several new minilabs, special facilities that would be used repeatedly on future flights. Two elaborate crystal growth furnaces, a life support and housing facility for small animals, and two types of apparatus for the study of fluids were evaluated on their inaugural flight. In this photograph, astronaut Don Lind observes the mercuric iodide growth experiment through a microscope at the vapor crystal growth furnace. The goals of this investigation were to grow near-perfect single crystals of mercuric iodide and to gain improved understanding of crystal growth by a vapor process. Mercuric iodide crystals have practical use as sensitive x-ray and gamma-ray detectors, and in portable detector devices for nuclear power plant monitoring, natural resource prospecting, biomedical applications in diagnosis and therapy, and in astronomical instruments. Managed by the Marshall Space Flight Center, Spacelab-3 (STS-51B) was launched aboard the Space Shuttle Orbiter Challenger on April 29, 1985.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-06-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-08-15

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

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

    International Nuclear Information System (INIS)

    Palmer, C J

    2010-01-01

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

  2. Quality control measurements for digital x-ray detectors

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, N W [Department of Radiology, University Hospitals Leuven, 49 Herenstraat, 3000 Leuven (Belgium); Mackenzie, A [National Co-ordinating Centre for the Physics of Mammography, Medical Physics, Level B, St Luke' s Wing, The Royal Surrey County Hospital NHS Trust, Egerton Road, Guildford, GU2 7XX (United Kingdom); Honey, I D, E-mail: nicholas.marshall@uz.kuleuven.ac.be [Department of Medical Physics, Floor 3, Henriette Raphael House, Guy' s and St Thomas' Hospital, London, SE1 9RT (United Kingdom)

    2011-02-21

    This paper describes a digital radiography (DR) quality control protocol for DR detectors from the forthcoming report from the Institute of Physics and Engineering in Medicine (IPEM). The protocol was applied to a group of six identical caesium iodide (CsI) digital x-ray detectors to assess reproducibility of methods, while four further detectors were assessed to examine the wider applicability. Twelve images with minimal spatial frequency processing are required, from which the detector response, lag, modulation transfer function (MTF), normalized noise power spectrum (NNPS) and threshold contrast-detail (c-d) detectability are calculated. The x-ray spectrum used was 70 kV and 1 mm added copper filtration, with a target detector air kerma of 2.5 {mu}Gy for the NNPS and c-d results. In order to compare detector performance with previous imaging technology, c-d data from four screen/film systems were also acquired, at a target optical density of 1.5 and an average detector air kerma of 2.56 {mu}Gy. The DR detector images were typically acquired in 20 min, with a further 45 min required for image transfer and analysis. The average spatial frequency for the 50% point of the MTF for six identical detectors was 1.29 mm{sup -1} {+-} 0.05 (3.9% coefficient of variation (cov)). The air kerma set for the six systems was 2.57 {mu}Gy {+-} 0.13 (5.0% cov) and the NNPS at this air kerma was 1.42 x 10{sup -5} mm{sup 2} (6.5% cov). The detective quantum efficiency (DQE) measured for the six identical detectors was 0.60 at 0.5 mm{sup -1}, with a maximum cov of 10% at 2.9 mm{sup -1}, while the average DQE was 0.56 at 0.5 mm{sup -1} for three CsI detectors from three different manufacturers. Comparable c-d performance was found for these detectors (5.9% cov) with an average threshold contrast of 0.46% for 11 mm circular discs. The average threshold contrast for the S/F systems was 0.70% at 11 mm, indicating superior imaging performance for the digital systems. The protocol was found

  3. 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.

  4. Compound Semiconductor Radiation Detector

    International Nuclear Information System (INIS)

    Kim, Y. K.; Park, S. H.; Lee, W. G.; Ha, J. H.

    2005-01-01

    In 1945, Van Heerden measured α, β and γ radiations with the cooled AgCl crystal. It was the first radiation measurement using the compound semiconductor detector. Since then the compound semiconductor has been extensively studied as radiation detector. Generally the radiation detector can be divided into the gas detector, the scintillator and the semiconductor detector. The semiconductor detector has good points comparing to other radiation detectors. Since the density of the semiconductor detector is higher than that of the gas detector, the semiconductor detector can be made with the compact size to measure the high energy radiation. In the scintillator, the radiation is measured with the two-step process. That is, the radiation is converted into the photons, which are changed into electrons by a photo-detector, inside the scintillator. However in the semiconductor radiation detector, the radiation is measured only with the one-step process. The electron-hole pairs are generated from the radiation interaction inside the semiconductor detector, and these electrons and charged ions are directly collected to get the signal. The energy resolution of the semiconductor detector is generally better than that of the scintillator. At present, the commonly used semiconductors as the radiation detector are Si and Ge. However, these semiconductor detectors have weak points. That is, one needs thick material to measure the high energy radiation because of the relatively low atomic number of the composite material. In Ge case, the dark current of the detector is large at room temperature because of the small band-gap energy. Recently the compound semiconductor detectors have been extensively studied to overcome these problems. In this paper, we will briefly summarize the recent research topics about the compound semiconductor detector. We will introduce the research activities of our group, too

  5. Epidemiology of thyroid disorders and valuation of effects of iodide administration in the Sejny community (Poland) after Chernobyl accident

    International Nuclear Information System (INIS)

    Zimnicki, P.

    1993-01-01

    The epidemiology of thyroid disorders was studied and the effect of potassium iodide administration was evaluated in citizens of Sejny (Poland) community four years after Chernobyl accident. The endemic goiter was observed in this area. The elevated levels of anti-human thyroid membrane antibodies and anti-human thereoglobuline antibody were found in 5.5% of children that had undergone iodide administration after Chernobyl accident. It may result from iodide administration or from endemic goiter. (author). 127 refs, 9 figs, 16 tabs

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-05-15

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

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

    International Nuclear Information System (INIS)

    Holm, J.; Glaenneskog, H.; Ekberg, C.; Kaerkelae, T.; Auvinen, A.

    2010-05-01

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

  8. Gamma-Ray Background Variability in Mobile Detectors

    Science.gov (United States)

    Aucott, Timothy John

    . This is accomplished by making many hours of background measurements with a truck-mounted system, which utilizes high-purity germanium detectors for spectroscopy and sodium iodide detectors for coded aperture imaging. This system also utilizes various peripheral sensors, such as panoramic cameras, laser ranging systems, global positioning systems, and a weather station to provide context for the gamma-ray data. About three hundred hours of data were taken in the San Francisco Bay Area, covering a wide variety of environments that might be encountered in operational scenarios. These measurements were used in a source injection study to evaluate the sensitivity of different algorithms (imaging and spectroscopy) and hardware (sodium iodide and high-purity germanium detectors). These measurements confirm that background distributions in large, mobile detector systems are dominated by systematic, not statistical variations, and both spectroscopy and imaging were found to substantially reduce this variability. Spectroscopy performed better than the coded aperture for the given scintillator array (one square meter of sodium iodide) for a variety of sources and geometries. By modeling the statistical and systematic uncertainties of the background, the data can be sampled to simulate the performance of a detector array of arbitrary size and resolution. With a larger array or lower resolution detectors, however imaging was better able to compensate for background variability.

  9. Drift Chambers detectors; Detectores de deriva

    Energy Technology Data Exchange (ETDEWEB)

    Duran, I; Martinez laso, L

    1989-07-01

    We present here a review of High Energy Physics detectors based on drift chambers. The ionization, drift diffusion, multiplication and detection principles are described. Most common drift media are analysed, and a classification of the detectors according to its geometry is done. Finally the standard read-out methods are displayed and the limits of the spatial resolution are discussed. (Author) 115 refs.

  10. De-mercurization of wastewater by Bacillus cereus (JUBT1): Growth kinetics, biofilm reactor study and field emission scanning electron microscopic analysis

    International Nuclear Information System (INIS)

    Ghoshal, Sanjukta; Bhattacharya, Pinaki; Chowdhury, Ranjana

    2011-01-01

    Graphical abstract: The assembly of biofilm reactor, based on attached growth of Bacillus cereus (JUBT1) on rice husk packing, and an activated carbon filter has been able to ensure the removal of mercury up to near-zero level. Highlights: → A new mercury resistant bacterial strain, Bacillus cereus (JUBT1), has been isolated. → Growth kinetics has been determined. → Biofilm reactor using attached growth of bacteria ensures near-zero level of mercury. → Confinement of mercury is confirmed through energy dispersive spectrometric analysis. - Abstract: Removal of mercuric ions by a mercury resistant bacteria, called Bacillus cereus (JUBT1), isolated from the sludge of a local chlor-alkali industry, has been investigated. Growth kinetics of the bacteria have been determined. A multiplicative, non-competitive relationship between sucrose and mercury ions has been observed with respect to bacterial growth. A combination of biofilm reactor, using attached growth of Bacillus cereus (JUBT1) on rice husk packing, and an activated carbon filter has been able to ensure the removal of mercury up to near-zero level. Energy dispersive spectrometry analysis of biofilm and the activated carbon has proved the transformation of Hg 2+ to Hg 0 and its confinement in the system.

  11. Curcuma longa Linn. extract and curcumin protect CYP 2E1 enzymatic activity against mercuric chloride-induced hepatotoxicity and oxidative stress: A protective approach.

    Science.gov (United States)

    Joshi, Deepmala; Mittal, Deepak Kumar; Shukla, Sangeeta; Srivastav, Sunil Kumar; Dixit, Vaibhav A

    2017-07-05

    The present investigation has been conducted to evaluate the therapeutic potential of Curcuma longa (200mgkg -1 , po) and curcumin (80mgkg -1 , po) for their hepatoprotective efficacy against mercuric chloride (HgCl 2 : 12μmolkg -1 , ip; once only) hepatotoxicity. The HgCl 2 administration altered various biochemical parameters, including transaminases, alkaline phosphatase, lactate dehydrogenase, bilirubin, gamma-glutamyl transferase, triglycerides and cholesterol contents with a concomitant decline in protein and albumin concentration in serum which were restored towards control by therapy of Curcuma longa or curcumin. On the other hand, both treatments showed a protective effect on drug metabolizing enzymes viz. aniline hydroxylase (AH) and amidopyrine-N-demethylase (AND), hexobarbitone induced sleep time and BSP retention. Choleretic, 1,1-diphenyl-2-picryl-hydrazil (DPPH)-free radical scavenging activities and histological studies also supported the biochemical findings. The present study concludes that Curcuma longa extract or curcumin has the ability to alleviate the hepatotoxic effects caused by HgCl 2 in rats. Copyright © 2017 Elsevier GmbH. All rights reserved.

  12. The effect of selenium on the biliary excretion and organ distribution of mercury in the rat after exposure to methyl mercuric chloride

    International Nuclear Information System (INIS)

    Alexander, J.; Norseth, T.

    1979-01-01

    The influence of selenium compounds on the biliary excretion and the organ distribution of mercury after injection of methyl mercuric chloride(4μmol/kg) have been tested. Selenite, seleno-di-N-acetylglycine and seleno-methionine strongly inhibited the biliary excretion of mercury. Selenite even in a molar dose of 1/40 of the methyl mercury dose inhibited the biliary excretion of mercury. The loss toxic seleno-di-N-acetylglycine was needed in larger molar doses and did not act as rapidly as selenite. Biliary excreted methyl mercury is known to be partly reabsorbed in the gut. Subsequently a part of it is deposited in the kidneys since drainage of the bile lowered the kidney content of mercury. Rats given selenium compounds in combination with bile drainage showed further reduction of the kidney mercury content than bile duct drainage alone. Thus the demonstrated lowering effect of selenium compounds on the kidney mercury content cannot be completely explained by an inhibition of biliary excretion of mercury. The mercury concentration in the brain was increased by the selenium compounds; the effect being dependent of the selenium dose reaching a maximum at an equimolar selenite - to methyl mercury dose ratio. The mechanisms by which selenium influences the methyl mercury kinetics are discussed. (author)

  13. Solvation effect on decomposition rate of 10-methyl-10-phenylphenoxarsonium iodide in some alcohols and ketones

    International Nuclear Information System (INIS)

    Gavrilov, V.I.; Gumerov, N.S.; Rakhmatullin, R.R.

    1989-01-01

    By the method of conductometry decomposition kinetics of 10-methyl-10phenylphenoxarsonium iodide in methanol, ethanol, 2-propanol, 1-butanol, 1-pentanol and methyl ethyl ketone at initial concentration of the salt 0.00024-0.003 mol/l, is studied. It is shown that at the temperatures up to 80-95 deg C practically no decomposition of arsonium salt in methanol and ethanol is observed. With an increase in the length of alcohol alkyl radical the decomposition rate increases. The values of activation enrgy both for alcohols and ketone are approximately the same. At the same time, decomposition rate in alcohol proved much slower than in ketone, which is related to iodide-ion solvation in protic solvents

  14. Solvation effect on decomposition rate of 10-methyl-10-phenylphenoxarsonium iodide in some alcohols and ketones

    Energy Technology Data Exchange (ETDEWEB)

    Gavrilov, V I; Gumerov, N S; Rakhmatullin, R R [Kazanskij Khimiko-Tekhnologicheskij Inst., Kazan (USSR)

    1989-03-01

    By the method of conductometry decomposition kinetics of 10-methyl-10phenylphenoxarsonium iodide in methanol, ethanol, 2-propanol, 1-butanol, 1-pentanol and methyl ethyl ketone at initial concentration of the salt 0.00024-0.003 mol/l, is studied. It is shown that at the temperatures up to 80-95 deg C practically no decomposition of arsonium salt in methanol and ethanol is observed. With an increase in the length of alcohol alkyl radical the decomposition rate increases. The values of activation enrgy both for alcohols and ketone are approximately the same. At the same time, decomposition rate in alcohol proved much slower than in ketone, which is related to iodide-ion solvation in protic solvents.

  15. Fast iodide-SAD phasing for high-throughput membrane protein structure determination.

    Science.gov (United States)

    Melnikov, Igor; Polovinkin, Vitaly; Kovalev, Kirill; Gushchin, Ivan; Shevtsov, Mikhail; Shevchenko, Vitaly; Mishin, Alexey; Alekseev, Alexey; Rodriguez-Valera, Francisco; Borshchevskiy, Valentin; Cherezov, Vadim; Leonard, Gordon A; Gordeliy, Valentin; Popov, Alexander

    2017-05-01

    We describe a fast, easy, and potentially universal method for the de novo solution of the crystal structures of membrane proteins via iodide-single-wavelength anomalous diffraction (I-SAD). The potential universality of the method is based on a common feature of membrane proteins-the availability at the hydrophobic-hydrophilic interface of positively charged amino acid residues with which iodide strongly interacts. We demonstrate the solution using I-SAD of four crystal structures representing different classes of membrane proteins, including a human G protein-coupled receptor (GPCR), and we show that I-SAD can be applied using data collection strategies based on either standard or serial x-ray crystallography techniques.

  16. Abstraction of iodine from aromatic iodides by alkyl radicals: steric and electronic effects.

    Science.gov (United States)

    Dolenc, Darko; Plesnicar, Bozo

    2006-10-13

    Abstraction of the iodine atom from aryl iodides by alkyl radicals takes place in some cases very efficiently despite the unfavorable difference in bond dissociation energies of C-I bonds in alkyl and aryl iodides. The abstraction is most efficient in iodobenzenes, ortho-substituted with bulky groups. The ease of abstraction can be explained by the release of steric strain during the elimination of the iodine atom. The rate of abstraction correlates fairly well with the strain energy, calculated by density functional theory (DFT) and Hartree-Fock (HF) methods as a difference in the total energy of ortho and para isomers. However, besides the steric bulk, the presence of some other functional groups in an ortho substituent also influences the rate. The stabilization of the transition state, resembling a 9-I-2 iodanyl radical, by electron-withdrawing groups seems to explain a positive sign of the Hammett rho value in the radical abstraction of halogen atoms.

  17. Lymphocutaneous Sporotrichosis Treated with Potassium Iodide with Development of Subclinical Hypothyroidism: Wolff-Chaikoff Effect?

    Science.gov (United States)

    Arora, Pooja; Raihan, M; Kubba, Asha; Gautam, Ram K

    2017-01-01

    Sporotrichosis is a subcutaneous mycotic infection caused by Sporothrix schenckii that is acquired by traumatic implantation. The diagnosis is established by demonstration of fungal elements on histopathology and culture. Potassium iodide, azole antifungals, and terbinafine are the treatment options available. In this article, we report a 60-year-old female with lymphocutaneous sporotrichosis that responded well to potassium iodide. However, subclinical hypothyroidism (Wolff-Chaikoff effect) was encountered as a side effect of therapy which was managed with thyroxine replacement. Knowledge about the Wolff-Chaikoff effect (WCE) is important for the dermatologist and reinforces the need for screening and monitoring of thyroid stimulating hormone (TSH) in patients where long duration therapy is being planned.

  18. Small-molecule inhibitors of sodium iodide sym-porter function

    International Nuclear Information System (INIS)

    Lecat-Guillet, N.; Merer, G.; Lopez, R.; Rousseau, B.; Ambroise, Y.; Pourcher, T.

    2008-01-01

    The Na + /l - sym-porter (NIS) mediates iodide uptake into thyroid follicular cells. Although NIS has been cloned and thoroughly studied at the molecular level, the biochemical processes involved in post-translational regulation of NIS are still unknown. The purpose of this study was to identify and characterize inhibitors of NIS function. These small organic molecules represent a starting point in the identification of pharmacological tools for the characterization of NIS trafficking and activation mechanisms. screening of a collection of 17020 drug-like compounds revealed new chemical inhibitors with potencies down to 40 nM. Fluorescence measurement of membrane potential indicates that these inhibitors do not act by disrupting the sodium gradient. They allow immediate and total iodide discharge from preloaded cells in accord with a specific modification of NIS activity, probably through distinct mechanisms. (authors)

  19. Small-molecule inhibitors of sodium iodide sym-porter function

    Energy Technology Data Exchange (ETDEWEB)

    Lecat-Guillet, N.; Merer, G.; Lopez, R.; Rousseau, B.; Ambroise, Y. [CEA, DSV, Dept Bioorgan Chem et Isotop Labelling, Inst Biol et Biotechnol iBiTecS, F-91191 Gif Sur Yvette (France); Pourcher, T. [Univ Nice Sophia Antipolis, Dept Biochem et Nucl Toxicol, F-06107 Nice (France)

    2008-07-01

    The Na{sup +}/l{sup -} sym-porter (NIS) mediates iodide uptake into thyroid follicular cells. Although NIS has been cloned and thoroughly studied at the molecular level, the biochemical processes involved in post-translational regulation of NIS are still unknown. The purpose of this study was to identify and characterize inhibitors of NIS function. These small organic molecules represent a starting point in the identification of pharmacological tools for the characterization of NIS trafficking and activation mechanisms. screening of a collection of 17020 drug-like compounds revealed new chemical inhibitors with potencies down to 40 nM. Fluorescence measurement of membrane potential indicates that these inhibitors do not act by disrupting the sodium gradient. They allow immediate and total iodide discharge from preloaded cells in accord with a specific modification of NIS activity, probably through distinct mechanisms. (authors)

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

    Directory of Open Access Journals (Sweden)

    Veissid N.

    1999-01-01

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

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

    Science.gov (United States)

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

    2017-01-01

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

  2. Measurements of rates of some reactions related to radiolytic effect on aqueous iodide solution

    International Nuclear Information System (INIS)

    Shiraishi, H.; Okuda, H.; Ishigure, K.

    1986-01-01

    A number of reactions takes place concurrently when aqueous iodide solution is subjected to radiation field. In order to help analyze this complicated radiation effect measurements of rate constants were undertaken for several important reactions. One of these concerns reduction of hypoiodous acid by hydrogen peroxide. For this reaction catalytic effect was found to be significant, and old rate data was revised. Measurements on reactions involving radicals were carried out by use of pulse radiolysis technique, which also include reexamination of results by previous workers. The reactions studied are (1) oxidation of iodide ion by hydroxyl radical (2) recombination reactions of atomic iodine and diiodide ion and (3) reduction of atomic and molecular iodine either by superoxide ion or by hydroperoxyl radical

  3. Performance of non-coconut base adsorbers in removal of iodine and organic iodides

    International Nuclear Information System (INIS)

    Rivers, R.D.; Pasha, M.; Fowler, E.E.; Goldsmith, J.M.

    1975-01-01

    Systems for the removal of radioactive iodine and organic iodides have used impregnated coconut shell activated carbons almost exclusively. Coconut shell carbons have some disadvantages: their geographical origin determines their trace chemical content; pore structures and impregnant effectiveness are highly dependent on activation and impregnation techniques. The authors report laboratory performance of a group of iodine-organic iodide adsorbers using bases other than coconut shell carbon. These have been evaluated in conformity with USAEC Regulatory Guide 1.52 and RDT M16 1T. Performance with regard to 131 I 2 and CH 3 131 I penetration and high-temperature elution have equaled or exceeded both the requirements of Guide 1.52 and results on typical coconut-shell carbons. Some performance outside Guide 1.52 ranges is included. Experimental problems in simulated LOCA testing are discussed. (U.S.)

  4. Parametric study on removal efficiency of impregnated activated charcoal and silver zeolite for radioactive methyl iodide

    International Nuclear Information System (INIS)

    Shiomi, H.; Yuasa, Y.; Tani, A.; Ohki, M.; Nakagawa, T.

    1983-01-01

    The removal efficiency of impregnated activated charcoal and silver zeolite for radioactive methyl iodide is influenced by various parameters such as temperature, relative humidity, face velocity and packing density. This study is to evaluate the dependency of the removal efficiency on each parameter and these combined parameters, quantitatively. Four types of adsorbents, BC-727, AgX, CHC-50 and SS 208C 5KI 3 , were tested. From experimental data and mass transfer theory, an experimental equation for evaluating the removal efficiency of adsorbents was derived under a series of experiments for radioactive methyl iodine-131. It was concluded that the removal efficiency calculated from the experimental equation agreed well with the experimental value. Effects of experimental specific parameters, such as Pre-flow time, methyl iodide injection time and After-flow time, on the removal efficiency of adsorbent are also described

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

    Data.gov (United States)

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

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

    KAUST Repository

    Weng, Zhiqiang

    2011-06-13

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

  7. Mica fission detectors

    International Nuclear Information System (INIS)

    Wong, C.; Anderson, J.D.; Hansen, L.; Lehn, A.V.; Williamson, M.A.

    1977-01-01

    The present development status of the mica fission detectors is summarized. It is concluded that the techniques have been refined and developed to a state such that the mica fission counters are a reliable and reproducible detector for fission events

  8. Barrier Infrared Detector (BIRD)

    Data.gov (United States)

    National Aeronautics and Space Administration — A recent breakthrough in MWIR detector design, has resulted in a high operating temperature (HOT) barrier infrared detector (BIRD) that is capable of spectral...

  9. Simulating detectors dead time

    International Nuclear Information System (INIS)

    Rustom, Ibrahim Farog Ibrahim

    2015-06-01

    Nuclear detectors are used in all aspects of nuclear measurements. All nuclear detectors are characterized by their dead time i.e. the time needed by a detector to recover from a previous incident. A detector dead time influences measurements taken by a detector and specially when measuring high decay rate (>) where is the detector dead time. Two models are usually used to correct for the dead time effect: the paralayzable and the non-paralayzable models. In the current work we use Monte Carlo simulation techniques to simulate radioactivity and the effect of dead time and the count rate of a detector with a dead time =5x10 - 5s assuming the non-paralayzable model. The simulation indicates that assuming a non -paralayzable model could be used to correct for decay rate measured by a detector. The reliability of the non-paralayzable model to correct the measured decay rate could be gauged using the Monte Carlo simulation. (Author)

  10. Forward tracking detectors

    Indian Academy of Sciences (India)

    Abstract. Forward tracking is an essential part of a detector at the international linear collider (ILC). The requirements for forward tracking are explained and the proposed solutions in the detector concepts are shown.

  11. Preparation of an ultra-fine, slightly dispersed silver iodide aerosol

    International Nuclear Information System (INIS)

    Poc, Marie-Martine

    1973-01-01

    A silver iodide aerosol was prepared under clean conditions. The method was to react iodine vapor with a silver aerosol in an inert dry atmosphere and in darkness. Great care was taken to avoid contamination from atmosphere air. The ice nucleating properties of the ultrafine AgI aerosol obtained were studied in a cloud mixing chamber: the aerosol was found to be strangely inactive. (author) [fr

  12. High Chloride Doping Levels Stabilize the Perovskite Phase of Cesium Lead Iodide.

    Science.gov (United States)

    Dastidar, Subham; Egger, David A; Tan, Liang Z; Cromer, Samuel B; Dillon, Andrew D; Liu, Shi; Kronik, Leeor; Rappe, Andrew M; Fafarman, Aaron T

    2016-06-08

    Cesium lead iodide possesses an excellent combination of band gap and absorption coefficient for photovoltaic applications in its perovskite phase. However, this is not its equilibrium structure under ambient conditions. In air, at ambient temperature it rapidly transforms to a nonfunctional, so-called yellow phase. Here we show that chloride doping, particularly at levels near the solubility limit for chloride in a cesium lead iodide host, provides a new approach to stabilizing the functional perovskite phase. In order to achieve high doping levels, we first co-deposit colloidal nanocrystals of pure cesium lead chloride and cesium lead iodide, thereby ensuring nanometer-scale mixing even at compositions that potentially exceed the bulk miscibility of the two phases. The resulting nanocrystal solid is subsequently fused into a polycrystalline thin film by chemically induced, room-temperature sintering. Spectroscopy and X-ray diffraction indicate that the chloride is further dispersed during sintering and a polycrystalline mixed phase is formed. Using density functional theory (DFT) methods in conjunction with nudged elastic band techniques, low-energy pathways for interstitial chlorine diffusion into a majority-iodide lattice were identified, consistent with the facile diffusion and fast halide exchange reactions observed. By comparison to DFT-calculated values (with the PBE exchange-correlation functional), the relative change in band gap and the lattice contraction are shown to be consistent with a Cl/I ratio of a few percent in the mixed phase. At these incorporation levels, the half-life of the functional perovskite phase in a humid atmosphere increases by more than an order of magnitude.

  13. 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.

  14. Determination of opium and strychnos alkaloids by radiometric titrations with potassium thallium(I) iodide reagent

    International Nuclear Information System (INIS)

    Rama Rao, V.V.; Singh, N.J.; Tandon, S.N.

    1980-01-01

    The titrations were carried out by the batch method in test tubes, using 204 Tl-labelled potassium thallium(I) iodide as precipitant for alkaloids such as codeine, morphine, narcotine, papaverine, thebaine, strychnine and brucine. Direct and reverse titrations were investigated including sensitivity and accuracy. Codeine and narcotine were determined in some pharmaceutical preparations such as codeine sulfate tablets, codopyrin tablets and coscopin syrup

  15. Thermodynamic characteristics of viscous flow activation in aqueous solutions of alkali metal iodides

    International Nuclear Information System (INIS)

    Renskij, I.A.; Rudnitskaya, A.A.; Fialkov, Yu.A.

    2003-01-01

    The Gibbs activation energy of the viscous flow of the alkali metal iodides aqueous solutions MI (M = Li, Na, K, Cs) and from its temperature dependence - the enthalpy and entropy of this process are calculated by the Eyring modified equation. The kinetic compensation effects, related to the viscous flow of the unbound water and to the ion-hydrate complexes are established. The relative contribution of the enthalpy and entropy constituents for these solution components is analyzed [ru

  16. Preliminary Design of Molecular Sieve for Removing Organic Iodide in Containment Filtered Venting System

    Energy Technology Data Exchange (ETDEWEB)

    Park, Tong Kyu; Shin, So Eun; Lee, Byung Chul [Heungdeok IT Valley Bldg., Yongin (Korea, Republic of); Kim, Hong Hyun; Lee, Kyung Jun [Gemvax and KAEL Inc., Daejeon (Korea, Republic of)

    2014-05-15

    In this paper, to increase the DF for gaseous iodine species, especially organic iodide, molecular sieve filled by silver exchanged zeolites is proposed and designed preliminarily. Its aerodynamic analysis is also performed and presented. In order to increase the DF for gaseous organic iodide, deep-bed type molecular sieve was proposed and designed preliminarily. Total 1,620kg of silver exchanged zeolites were filled evenly in 10 beds of the molecular sieve. The safety factor in the case of 20m{sup 3}/s will be smaller than the counterpart of the standard case (6m{sup 3}/s). However, if the adsorption capacity of the zeolites is larger than 3.09mg/g when the residence time is 0.09 second, the designed molecular sieve can be used at 20m3/s of volumetric flow rate. The removal efficiency for organic iodide should be considered as well as economical aspects in the design of molecular sieve. In the event of nuclear power plant (NPP) severe accident, the nuclear reactor containment might suffer damage resulting from overpressure caused by decay heat. In order to prevent this containment damage, containment venting has been considered as one of effective methods. However, since vented gases contain radioactive fission products, they should be filtered to be released to environment. Generally, containment filtered venting system (CFVS) is installed on NPP to achieve this aim. Even though great amount of efforts have been devoted to developing the CFVS using various filtering methods, the decontaminant factor (DF) for radioactive gaseous iodide is still unsatisfactory while DFs for radioactive aerosols and elemental iodine are very high.

  17. Rhodium-catalyzed triarylphosphine synthesis via cross-coupling of aryl iodides and acylphosphines

    Directory of Open Access Journals (Sweden)

    Jiefang Yang

    2018-01-01

    Full Text Available Rhodium(I-catalyzed C–P cross-coupling reaction with aryl iodides and acylphosphines was disclosed for a straight forward synthesis of triarylphosphines. The acylphosphines were successfully employed as both the phosphorus source and the ligand to the Rh(I catalyst. The triarylphosphines could be afforded in a yield up to 98% with good toleration of wide functional groups.

  18. Film formation of non-planar phthalocyanines on copper(i) iodide

    OpenAIRE

    Ramadan, A. J.; Fearn, S.; Jones, T. S. (Tim S.); Heutz, S.; Rochford, L. A. (Luke A.)

    2016-01-01

    Structural templating is frequently used in organic photovoltaic devices to control the properties of the functional layers and therefore improve efficiencies. Modification of the substrate temperatures has also been shown to impact the structure and morphology of phthalocyanine thin films. Here we combine templating by copper iodide and high substrate temperature growth and study its effect on the structure and morphology of two different non-planar phthalocyanines, chloroaluminium (ClAlPc) ...

  19. Charge Carrier Dynamics of Methylammonium Lead-Iodide Perovskite Solar Cells

    OpenAIRE

    Neukom, Martin Thomas

    2016-01-01

    Transient opto-electrical measurements of methylammonium lead iodide (MALI) perovskite solar cells (PSCs) are performed and analyzed in order to elucidate the operating mechanisms. The current response to a light pulse or voltage pulse shows an extraordinarily broad dynamic range covering 9 orders of magnitude in time - from microseconds to minutes - until steady-state is reached. Evidence of a slowly changing charge density at the perovskite layer boundaries is found, which is most probably ...

  20. Iodide-photocatalyzed reduction of carbon dioxide to formic acid with thiols and hydrogen sulfide

    OpenAIRE

    Berton, Mateo Otao; Mello, Rossella C. C.; González Núñez, María Elena

    2016-01-01

    The photolysis of iodide anions promotes the reaction of carbon dioxide with hydrogen sulfide or thiols to quantitatively yield formic acid and sulfur or disulfides. The reaction proceeds in acetonitrile and aqueous solutions, at atmospheric pressure and room temperature by irradiation using a low-pressure mercury lamp. This transition-metal-free photocatalytic process for CO2 capture coupled with H2S removal may have been relevant as a prebiotic carbon dioxide fixation.

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

    Directory of Open Access Journals (Sweden)

    Andrzej Tracz

    2015-10-01

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

  2. HIBP primary beam detector

    International Nuclear Information System (INIS)

    Schmidt, T.W.

    1979-01-01

    A position measuring detector was fabricated for the Heavy Ion Beam Probe. The 11 cm by 50 cm detector was a combination of 15 detector wires in one direction and 63 copper bars - .635 cm by 10 cm to measure along an orthogonal axis by means of a current divider circuit. High transmission tungsten meshes provide entrance windows and suppress secondary electrons. The detector dimensions were chosen to resolve the beam position to within one beam diameter

  3. The OSMOND detector

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E. [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Dalgliesh, R. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Duxbury, D.M., E-mail: dom.duxbury@stfc.ac.uk [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Helsby, W.I. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Holt, S.A.; Kinane, C.J. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Marsh, A.S. [Diamond Light Source LTD, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire, OX11 0DE (United Kingdom); Rhodes, N.J.; Schooneveld, E.M. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Spill, E.J.; Stephenson, R. [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom)

    2013-01-11

    The development and testing of the Off Specular MicrOstrip Neutron Detector (OSMOND) is described. Based on a microstrip gas chamber the aim of the project was to produce a high counting rate detector capable of replacing the existing rate limited scintillator detectors currently in use on the CRISP reflectometer for off specular reflectometry experiments. The detector system is described together with results of neutron beam tests carried out at the ISIS spallation neutron source.

  4. Cosmogenic production of tritium in dark matter detectors

    Science.gov (United States)

    Amaré, J.; Castel, J.; Cebrián, S.; Coarasa, I.; Cuesta, C.; Dafni, T.; Galán, J.; García, E.; Garza, J. G.; Iguaz, F. J.; Irastorza, I. G.; Luzón, G.; Martínez, M.; Mirallas, H.; Oliván, M. A.; Ortigoza, Y.; Ortiz de Solórzano, A.; Puimedón, J.; Ruiz-Chóliz, E.; Sarsa, M. L.; Villar, J. A.; Villar, P.

    2018-01-01

    The direct detection of dark matter particles requires ultra-low background conditions at energies below a few tens of keV. Radioactive isotopes are produced via cosmogenic activation in detectors and other materials and those isotopes constitute a background source which has to be under control. In particular, tritium is specially relevant due to its decay properties (very low endpoint energy and long half-life) when induced in the detector medium, and because it can be generated in any material as a spallation product. Quantification of cosmogenic production of tritium is not straightforward, neither experimentally nor by calculations. In this work, a method for the calculation of production rates at sea level has been developed and applied to some of the materials typically used as targets in dark matter detectors (germanium, sodium iodide, argon and neon); it is based on a selected description of tritium production cross sections over the entire energy range of cosmic nucleons. Results have been compared to available data in the literature, either based on other calculations or from measurements. The obtained tritium production rates, ranging from a few tens to a few hundreds of nuclei per kg and per day at sea level, point to a significant contribution to the background in dark matter experiments, requiring the application of specific protocols for target material purification, material storing underground and limiting the time the detector is on surface during the building process in order to minimize the exposure to the most dangerous cosmic ray components.

  5. Iodide Sorption to Clays and the Relationship to Surface Charge and Clay Texture - 12356

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Andrew; Kruichiak, Jessica; Tellez, Hernesto; Wang, Yifeng [Sandia National Laboratories, Albuquerque, NM 87185 (United States)

    2012-07-01

    Iodine is assumed to behave conservatively in clay barriers around nuclear waste repositories and in natural sediments. Batch experiments tend to show little to no sorption, while in column experiments iodine is often retarded relative to tritiated water. Current surface complexation theory cannot account for negatively charged ion sorption to a negatively charged clay particle. Surface protonation and iodide sorption to clay minerals were examined using surface titrations and batch sorption experiments with a suite of clay minerals. Surface titrations were completed spanning a range of both pH values and ionic strengths. For reference, similar titrations were performed on pure forms of an Al-O powder. The titration curves were deconvoluted to attain the pKa distribution for each material at each ionic strength. The pKa distribution for the Al-O shows two distinct peaks at 4.8 and 7.5, which are invariant with ionic strength. The pKa distribution of clays was highly variable between the different minerals and as a function of ionic strength. Iodide sorption experiments were completed at high solid:solution ratios to exacerbate sorption properties. Palygorskite and kaolinite had the highest amount of iodide sorption and montmorillonite had the least. (authors)

  6. Silver-Assisted Synthesis of Gold Nanorods: the Relation between Silver Additive and Iodide Impurities.

    Science.gov (United States)

    Jessl, Sarah; Tebbe, Moritz; Guerrini, Luca; Fery, Andreas; Alvarez-Puebla, Ramon A; Pazos-Perez, Nicolas

    2018-04-17

    Seed-mediated methods employing cetyltrimethylammonium bromide (CTAB) as a surfactant, and silver salts as additives, are the most common synthetic strategies for high-yield productions of quality Au nanorods. However, the mechanism of these reactions is not yet fully understood and, importantly, significant lab-to-lab reproducibility issues still affect these protocols. In this study, the direct correlation between the hidden content of iodide impurities in CTAB reagents, which can drastically differ from different suppliers or batches, and the optimal concentration of silver required to maximize the nanorods yield is demonstrated. As a result, high-quality nanorods are obtained at different iodide contents. These results are interpreted based on the different concentrations of CTAB and cetyltrimethylammonium iodide (CTAI) complexes with Ag + and Au + metal ions in the growth solution, and their different binding affinity and reduction potential on distinct crystallographic planes. Notably, the exhaustive conversion of CTAI-Au + to CTAI-Ag + appears to be the key condition for maximizing the nanorod yield. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. The influence of sodium salts (iodide, chloride and sulfate) on the formation efficiency of sulfamerazine nanocrystals.

    Science.gov (United States)

    Lou, Hao; Liu, Min; Qu, Wen; Johnson, James; Brunson, Ed; Almoazen, Hassan

    2014-08-01

    The purpose of this study is to evaluate the influence of sodium iodide, sodium chloride and sodium sulfate on the formation efficiency of sulfamerazine nanocrystals by wet ball milling. Sulfamerazine was milled using zirconium oxide beads in a solution containing polyvinylpyrrolidone (PVP) and a sodium salt (iodide, chloride or sulfate). Particle size distributions were evaluated by light diffraction before and after milling. High-performance liquid chromatography was utilized to determine the amount of PVP adsorbed onto sulfamerazine surface. Lyophilized nanocrystals were further characterized by differential scanning calorimetry and dissolution testing. Sulfate ion had more profound effect on reducing particle size via milling than iodide or chloride. We linked our findings to Hofmeister ion series, which indicates that sulfate ions tends to break the water structure, increases the surface tension and lowers the solubility of hydrocarbons in water. We hypothesized that the addition of sulfate ions dehydrated the PVP molecules and enhanced its adsorption onto the sulfamerazine particle surfaces. Consequently, the adsorbed PVP helped to stabilize of the nanosuspension. The nanocrystals that were obtained from the lyophilized milled suspensions exhibited a notable increase in dissolution rate. The addition of sodium sulfate enhanced the formation efficiency of sulfamerazine nanocrystals.

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

    Science.gov (United States)

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

    2018-01-01

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

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

    Science.gov (United States)

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

    2014-10-21

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

  10. Determination of microamounts of potassium in sodium iodide by atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Ogasawara, Ken; Ohta, Masatoshi; Abe, Kenzo

    1980-01-01

    Microdetermination of potassium in sodium iodide was developed by the standard addition method. Twenty grams of sample were dissolved in 50 ml of water in a quartz beaker. To the solution, 30 ml of concentrated hydrochloric acid and 30 ml of 30% hydrogen peroxide were added, and evaporated to dryness. By this process sodium iodide was converted into sodium chloride. The cake thus obtained was dissolved in water and diluted to exactly 200 ml. To 25 ml aliquots of the solution, the standard potassium and cesium chloride solutions were added and diluted to 50 ml with water; the concentration of potassium was 0 -- 1 mg/l and that of cesium 4 mM. These solutions were introduced into an air-propane flame and the absorbances were measured at 769.9 nm. During the conversion reaction, hydrochloric acid was completely decomposed, and remained hydrogen peroxide had no influence for absorbance, and other backgrounds were negligible. The linear calibration curve was obtained in the range 0 -- 2 mg of potassium per liter. Potassium in sodium iodide was determined by this method within the coefficient of variation of +-(20 -- 3)% in the range (1.7 -- 32.5) ppm. (author)

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

    Science.gov (United States)

    McDaniel, Jesse G; Yethiraj, Arun

    2018-01-11

    Highly ionic environments can mediate unusual chemical reactions that would otherwise be considered impossible based on chemical intuition. For example, the formation of a chemical bond between two iodide anions to form a divalent polyiodide anion is seemingly prohibited due to Coulombic repulsion. Using ab initio molecular dynamics simulations, we show that in the 1-ethyl-3-methylimidazolium (EMIM)/I 3 ionic crystal, the reactive formation of divalent and even trivalent polyiodide anions occurs with extremely small energetic barriers, due to the electrostatic field of the ionic lattice. A practical consequence of this anomalous reactivity is that iodide anions are efficiently transported within the crystal through a "Grotthuss-exchange" mechanism involving bond-breaking and forming events. We characterize two distinct transport pathways, involving both I 4 2- and I 7 3- intermediates, with fast transport of iodide resulting from the release of an I - anion on the opposite side of the intermediate species from the initial bond formation. The ordered cation arrangement in the crystal provides the necessary electrostatic screening for close approach of anions, suggesting a new counterintuitive approach to obtain high ionic conductivity. This new design principle could be used to develop better solid-state electrolytes for batteries, fuel cells, and supercapacitors.

  12. WORKSHOP: Scintillating fibre detectors

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    Scintillating fibre detector development and technology for the proposed US Superconducting Supercollider, SSC, was the subject of a recent workshop at Fermilab, with participation from the high energy physics community and from industry. Sessions covered the current status of fibre technology and fibre detectors, new detector applications, fluorescent materials and scintillation compositions, radiation damage effects, amplification and imaging structures, and scintillation fibre fabrication techniques

  13. Shielded regenerative neutron detector

    International Nuclear Information System (INIS)

    Terhune, J.H.; Neissel, J.P.

    1978-01-01

    An ion chamber type neutron detector is disclosed which has a greatly extended lifespan. The detector includes a fission chamber containing a mixture of active and breeding material and a neutron shielding material. The breeding and shielding materials are selected to have similar or substantially matching neutron capture cross-sections so that their individual effects on increased detector life are mutually enhanced

  14. The CAPRICE RICH detector

    Energy Technology Data Exchange (ETDEWEB)

    Basini, G. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Codino, A.; Grimani, C. [Perugia Univ. (Italy)]|[INFN, Perugia (Italy); De Pascale, M.P. [Rome Univ. `Tor Vergata` (Italy). Dip. di Fisica]|[INFN, Sezione Univ. `Tor Vergata` Rome (Italy); Cafagna, F. [Bari Univ. (Italy)]|[INFN, Bari (Italy); Golden, R.L. [New Mexico State Univ., Las Cruces, NM (United States). Particle Astrophysics Lab.; Brancaccio, F.; Bocciolini, M. [Florence Univ. (Italy)]|[INFN, Florence (Italy); Barbiellini, G.; Boezio, M. [Trieste Univ. (Italy)]|[INFN, Trieste (Italy)

    1995-09-01

    A compact RICH detector has been developed and used for particle identification in a balloon borne spectrometer to measure the flux of antimatter in the cosmic radiation. This is the first RICH detector ever used in space experiments that is capable of detecting unit charged particles, such as antiprotons. The RICH and all other detectors performed well during the 27 hours long flight.

  15. Self powered neutron detectors

    International Nuclear Information System (INIS)

    Gopalan, C.S.; Ramachandra Rao, M.N.; Ingale, A.D.

    1976-01-01

    Two types of self powered neutron detectors used for in-core flux measurements are described. The characteristics of the various detectors, with emitters Rh, V, Co, Py are presented. Details about the fabrication of these detectors are given. (A.K.)

  16. The JADE muon detector

    International Nuclear Information System (INIS)

    Allison, J.; Armitage, J.C.M.; Baines, J.T.M.; Ball, A.H.; Bamford, G.; Barlow, R.J.; Bowdery, C.K.; Chrin, J.T.M.; Duerdoth, I.P.; Glendinning, I.; Greenshaw, T.; Hassard, J.F.; Hill, P.; King, B.T.; Loebinger, F.K.; Macbeth, A.A.; McCann, H.; Mercer, D.; Mills, H.E.; Murphy, P.G.; Prosper, H.B.; Rowe, P.; Stephens, K.

    1985-01-01

    The JADE muon detector consists of 618 planar drift chambers interspersed between layers of hadron absorber. This paper gives a detailed description of the construction and operation of the detector as a whole and discusses the properties of the drift chambers. The muon detector has been operating successfully at PETRA for five years. (orig.)

  17. Economical stabilized scintillation detector

    International Nuclear Information System (INIS)

    Anshakov, O.M.; Chudakov, V.A.; Gurinovich, V.I.

    1983-01-01

    An economical scintillation detector with the stabilization system of an integral type is described. Power consumed by the photomultiplier high-voltage power source is 40 mW, energy resolution is not worse than 9%. The given detector is used in a reference detector of a digital radioisotope densimeter for light media which is successfully operating for several years

  18. Gas filled detectors

    International Nuclear Information System (INIS)

    Stephan, C.

    1993-01-01

    The main types of gas filled nuclear detectors: ionization chambers, proportional counters, parallel-plate avalanche counters (PPAC) and microstrip detectors are described. New devices are shown. A description of the processes involved in such detectors is also given. (K.A.) 123 refs.; 25 figs.; 3 tabs

  19. HP Ge planar detectors

    International Nuclear Information System (INIS)

    Gornov, M.G.; Gurov, Yu.B.; Soldatov, A.M.; Osipenko, B.P.; Yurkowski, J.; Podkopaev, O.I.

    1989-01-01

    Parameters of planar detectors manufactured of HP Ge are presented. The possibilities to use multilayer spectrometers on the base of such semiconductor detectors for nuclear physics experiments are discussed. It is shown that the obtained detectors including high square ones have spectrometrical characteristics close to limiting possible values. 9 refs.; 3 figs.; 1 tab

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

    International Nuclear Information System (INIS)

    Blount, Benjamin C.; Valentin-Blasini, Liza

    2006-01-01

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

  1. Administration of additional inactive iodide during radioiodine therapy for Graves' disease. Who might benefit?

    International Nuclear Information System (INIS)

    Dietlein, M.; Moka, D.; Reinholz, U.; Schmidt, M.; Schomaecker, K.; Schicha, H.; Wellner, U.

    2007-01-01

    Aim: Graves' hyperthyroidism and antithyroid drugs empty the intrathyroid stores of hormones and iodine. The consequence is rapid 131 I turnover and impending failure of radioiodine therapy. Can administration of additional inactive iodide improve 131I kinetics? Patients, methods: Fifteen consecutive patients, in whom the 48 h post-therapeutically calculated thyroid dose was between 150 and 249 Gy due to an unexpectedly short half-life, received 3 x 200 μg inactive potassium-iodide ( 127 I) daily for 3 days (Group A), while 17 consecutive patients with a thyroid dose of = 250 Gy (Group B) served as the non-iodide group. 48 hours after 131 I administration (M1) and 4 or 5 days later (M2) the following parameters were compared: effective 131 I half-life, thyroid dose, total T3, total T4, 131 I-activity in the T3- and T4-RIAs. Results: In Group A, the effective 131 I half-life M1 before iodine (3.81 ± 0.93 days) was significantly (p 131 I half-life M2 (4.65 ± 0.79 days). Effective 131 I half-life M1 correlated with the benefit from inactive 127 I (r = -0.79): Administration of 127 I was beneficial in patients with an effective 131 I half-life M1 of 131 I activity of T3 and T4 showed lower specific 131 I activity after addition of inactive iodine compared with patients from the same group with a lower initial specific 131 I activity of T3 and T4 and compared with the patient group B who was given no additional inactive iodide. This correlation was mathematically described and reflected in the flatter gradient in Group A (y = 0.5195x + 0.8727 for 131 I T3 and y = 1.0827x - 0.4444 for 131 I T4) and steeper gradient for Group B (y = 0.6998x + 0.5417 for 131 I T3 and y = 1.3191x - 0.2901 for 131 I T4). Radioiodine therapy was successful in all 15 patients from Group A. Conclusion: The administration of 600 μg inactive iodide for three days during radioiodine therapy in patients with Graves' hyperthyroidism and an unexpectedly short half-life of <3 or 4 days was a safe

  2. Radiation detectors laboratory

    International Nuclear Information System (INIS)

    Ramirez J, F.J.

    1997-01-01

    The Radiation detectors laboratory was established with the assistance of the International Atomic Energy Agency which gave this the responsibility to provide its services at National and regional level for Latin America and it is located at the ININ. The more expensive and delicate radiation detectors are those made of semiconductor, so it has been put emphasis in the use and repairing of these detectors type. The supplied services by this laboratory are: selection consultant, detectors installation and handling and associated systems. Installation training, preventive and corrective maintenance of detectors and detection systems calibration. (Author)

  3. The ATLAS Pixel Detector

    CERN Document Server

    Huegging, Fabian

    2006-06-26

    The contruction of the ATLAS Pixel Detector which is the innermost layer of the ATLAS tracking system is prgressing well. Because the pixel detector will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical sensor-chip-hybrid modules, arranged in three barrels in the centre and three disks on either side for the forward region. The position of the detector near the interaction point requires excellent radiation hardness, mechanical and thermal robustness, good long-term stability for all parts, combined with a low material budget. The final detector layout, new results from production modules and the status of assembly are presented.

  4. Effects of trichostatin a on the expression of sodium/iodide symporter mRNA and the uptake of iodide in human thyroid cancer cell lines

    International Nuclear Information System (INIS)

    Bao Jiandong; Lin Xiufeng; Yu Huixin; Tan Cheng; Zhang Li

    2010-01-01

    Objective: To investigate the sodium/iodide symporter (NIS) expression and iodide uptake in thyroid cancer cells induced by the histone deacetyltransferase inhibitors (HDACi), Trichostatin A (TSA). Methods: Both the thyroid cancer cell lines, follicular thyroid carcinoma cell line FTC-133 and papillary thyroid carcinoma cell line K1, were firstly induced with TSA for 48 h. Then, the expression of NIS mRNA was analysed with reverse transcription-polymerase chain reaction (RT-PCR), the densitometric ratio of NIS/glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was calculated, and the iodide uptake in the thyroid cancer cells was also measured. Independent-sample t-test and one-way analysis of variance (ANOVA) were used to analyze the data. Results: For FTC-133 cells, increased NIS mRNA expression was detected after 48 h of TSA treatment, and the changes were dose-dependent (F=32.56, P 0.05). Furthermore, FTC-133 cells showed the ability of accumulating radioiodide with 50 and 75 nmol/L TSA induction for 48 h: (15.42 ± 0.42) x 10 3 counts · min -1 · 10 -5 cells vs (8.46 ± 0.84) x 10 3 counts · min -1 · 10 -5 cells, t=3.018, P 3 counts · min -1 · 10 -5 cells vs (8.46 ± 0.84) x 10 3 counts · min -1 · 10 -5 cells, t=3.557, P 3 counts · min -1 · 10 -5 cells, (6.97 ± 0.65) x 10 3 counts · min -1 · 10 -5 cells vs (5.37 ± 0.88) x 10 3 counts · min -1 · 10 -5 cells, t=0.185, P> 0.05 and t = 0.332, P > 0.05, respectively. Conclusion: TSA induced upregulated NIS mRNA expression in follicular thyroid cancer cells and augmented radioiodide uptake in thyroid cancer cells, while TSA had no remarkable effect on papillary thyroid carcinoma cell. (authors)

  5. Adsorption behavior of calcined layered double hydroxides towards removal of iodide contaminants

    International Nuclear Information System (INIS)

    Lu Liang; He Jing; Wei Min; Evans, D.G.; Duan Xue

    2005-01-01

    Layered double hydroxides (LDHs), are a class of synthetic anionic clays whose structure can be described as containing brucite-like layers in which some of the divalent cations have been replaced by trivalent ions giving positively-charged sheets. This charge is balanced by intercalation of anions in the hydrated interlayer regions. The general formula is EM 2+ 1-x M 3+ x (OH) 2 ] x+ (A n- ) x/n · mH 2 O, where M 2+ and M 3+ are metal cations for example Mg 2+ and Al 3+ , that occupy octahedral sites in the hydroxide layers, A n- is an exchangeable anion, and x is the ratio M 3+ /(M 2+ + M 3+ ) and the layer charge will depend on the M 2+ /M 3+ ratio. LDHs act as sorbents of anionic species through two types of reactions, namely, anion exchange and reconstruction, which further adds the possibility of recycling and reuse. The sorption of anions from aqueous solutions by structural reconstruction of a calcined LDH is based on a very interesting property of these materials, the so-called memory effect: Calcination of LDHs produces intermediate non-stoichiometric oxides (CLDH) which undergo rehydration in aqueous medium and give back the hydroxide structure with different anions in the interlayers. Radioactive iodide is widely used in biological experiments, medical treatments and in diagnosis. During fission of uranium several iodine species are produced. All the short lived isotopes of iodine, including 1311 (half life 8.04 days), decay and only 127 I (stable) and 129 I (half life 1.59 x 10 7 years) remain as a problem. 129 I is especially considered as one of the key radionuclides that dominate the long-term radiation in underground radioactive waste stores. Iodine is one of the nuclides causing most concern among radioactive anions. Different adsorbents such as zeolites, silica gel, anion exchange paper membrane, activated carbon and activated carbon fibers, have been investigated as potential materials for elimination of iodide from liquid wastes. In this work

  6. Radiation detectors laboratory

    International Nuclear Information System (INIS)

    Ramirez J, F.J.

    1996-01-01

    The National Institute for Nuclear Research has established a Radiation detector laboratory that has the possibility of providing to the consultants on the handling and applications of the nuclear radiation detectors. It has special equipment to repair the radiation detectors used in spectroscopy as the hyper pure Germanium for gamma radiation and the Lithium-silica for X-rays. There are different facilities in the laboratory that can become useful for other institutions that use radiation detectors. This laboratory was created to satisfy consultant services, training and repairing of the radiation detectors both in national and regional levels for Latin America. The laboratory has the following sections: Nuclear Electronic Instrumentation; where there are all kind of instruments for the measurement and characterization of detectors like multichannel analyzers of pulse height, personal computers, amplifiers and nuclear pulse preamplifiers, nuclear pulses generator, aleatories, computer programs for radiation spectra analysis, etc. High vacuum; there is a vacuum escape measurer, two high vacuum pumps to restore the vacuum of detectors, so the corresponding measurers and the necessary tools. Detectors cleaning; there is an anaerobic chamber for the detectors handling at inert atmosphere, a smoke extraction bell for cleaning with the detector solvents. Cryogenic; there are vessels and tools for handling liquid nitrogen which is used for cooling the detectors when they required it. (Author)

  7. High-energy detector

    Science.gov (United States)

    Bolotnikov, Aleksey E [South Setauket, NY; Camarda, Giuseppe [Farmingville, NY; Cui, Yonggang [Upton, NY; James, Ralph B [Ridge, NY

    2011-11-22

    The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

  8. 37Ar based neutron source for calibration of the iodine solar neutrino detector

    International Nuclear Information System (INIS)

    Abdurashitov, D.N.; Gavrin, V.N.; Mirmov, I.N.; Veretenkin, E.P.; Yants, V.Eh.; Cleveland, B.T.; Davis, R. Jr.; Lande, K.; Wildenhain, P.; Khomyakov, Yu.S.

    2001-01-01

    The methodology of the creation of a compact neutrino source based on the 37 Ar isotope as well as the technique of calibration of an iodine detector of solar neutrinos is described. An important overall expected result is the creation of a prototype of the source with the intensity up to 400 kCi, delivery of this source to the Baksan neutrino observatory and the test calibration of the single module of the iodine detector. Simulation shows that at least 45-70 127 Xe atoms will be detected in the irradiation of ∼40 tons of methylene iodide by the source leading to ∼19% of the error on the measured production rate. This result should be considered as a test of the developed technology and will verify overall technical readiness for the creation of a full scale neutrino source and the full scale calibration of the iodine detector

  9. Scintillation characteristics of phosphich-detector for detection of beta- and gamma-radiations

    CERN Document Server

    Ananenko, A A; Gavrilyuk, V

    2002-01-01

    The results of the study on the influence of individual peculiarities of the compound scintillation detector structure on the value and stability of the light yield by the gamma- and beta-radiation combined registration are presented. The phosphich detector is manufactured from the sodium iodide monocrystal, activated by thallium, and the scintillation plastic on the polystyrol basis. The comparison of the experimental results with the mathematical modeling data revealed certain regularities of the process of forming the phosphich detector light signal. The recommendations are worked out by means whereof the following characteristics of the scintillation unit: the light yield and its stability, amplitude resolution and the peak-to-valley ratio by the gamma- and beta-radiation registration were improved

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

    Science.gov (United States)

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

    2014-03-28

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

  11. Investigations of portable cadmium telluride (CdTe(Cl)) detectors for clinical studies with radioactive indicators

    International Nuclear Information System (INIS)

    Bojsen, J.

    1985-01-01

    The combination of small, portable γ-radiation-sensitive Cadmium Telluride (CdTE(Cl)) crystal detectors and portable solid state data storage memories makes it feasible to extend the measuring period in a number of clinical investigations based on the use of various radioisotopes and external detection. Blood sampling can be avoided in some cases. Continuous ambulatory monitoring of relevant physiological parameters is practicable, e.g. kidney function (GFR), left ventricular ejection fraction, subcutaneous blood flow, muscle blood flow and insulin absorption in diabetic patients. In the present methodological study the applicability of the 133-Xe washout technique to subcutaneous (s.c.) adipose tissue blood flow (SBF) has been investigated and adapted to the use of CdTe(Cl) detectors attached to the skin surface for the measurement of local 133-Xe-disappearance rate constants (k). Physical characterization of CdTe(Cl) detectors as γ-sensitive devices has been performed, and adequate counting sensitivities were found without detector energy-resolution properties. The CdTe(Cl) detectors are therefore suitable for single indicator studies. The measuring geometry of CdTe(Cl) detectors was studied and compared with that of stationary Sodium Iodide (NaI(Tl)) detectors in both phantom and in vivo investigations. The spatial properties of CdTe(Cl) detectors could to some extent be adjusted by pulse height discrimination and lead collimation. When long-term measurements were complicated by for instance physical activity of the patients, the small CdTe(Cl) detectors in general showed equal or better performance than the heavy and voluminous NaI(Tl) detectors. The free movement of the ambulatory patient and the avoidance of cable connections to stationary data-collecting systems gave improved possibilities for measurements of the relevant parameters. From this point of view, portable CdTe(Cl) detectors must be considered an important advance for radioactivity studies in

  12. Attenuation by methyl mercury and mercuric sulfide of pentobarbital induced hypnotic tolerance in mice through inhibition of ATPase activities and nitric oxide production in cerebral cortex

    Energy Technology Data Exchange (ETDEWEB)

    Chuu, Jiunn-Jye; Huang, Zih-Ning; Yu, Hsun-Hsin; Chang, Liang-Hao [College of Engineering, Southern Taiwan University, Institute of Biotechnology, Tainan (China); Lin-Shiau, Shoei-Yn [College of Medicine, National Taiwan University, Institute of Pharmacology, Taipei (China)

    2008-06-15

    This study is aimed at exploring the possible mechanism of hypnosis-enhancing effect of HgS or cinnabar (a traditional Chinese medicine containing more than 95% HgS) in mice treated with pentobarbital. We also examined whether the effect of HgS is different from that of the well-known methyl mercury (MeHg). After a short period (7 days) of oral administration to mice, a nontoxic dose (0.1 g/kg) of HgS not only significantly enhanced pentobarbital-induced hypnosis but also attenuated tolerance induction; while a higher dose (1 g/kg) of HgS or cinnabar exerted an almost irreversible enhancing effect on pentobarbital-hypnosis similar to that of MeHg (2 mg/kg) tested, which was still effective even after 10 or 35 days cessation of administration. To study comparatively the effects of different mercury forms from oral administration of MeHg and HgS on membrane ATPase activities of experimental mice, analysis of the Hg content in the cerebral cortex revealed that correlated with the decrease of Na{sup +}/K{sup +}-ATPase and Ca{sup 2+}-ATPase activities. Furthermore, NO levels of blood but not that of cerebral cortex were also decreased by mercuric compounds. Although pentobarbital alone enhanced cytochrome p450-2C9 in time dependent manner, all of mercurial compounds tested had no such effect. All of these findings indicated that the mercurial compounds including cinnabar, HgS and MeHg exert a long-lasting enhancing hypnotic activity without affecting pentobarbital metabolism, which provides evidence-based sedative effect of cinnabar used in Chinese traditional medicine for more than 2,000 years. The nontoxic HgS dosing (0.1 g/kg/day) for consecutive 7 days is perhaps useful for delaying or preventing pentobarbital-tolerance. (orig.)

  13. Solubility of metallic mercury in organic solvents; Solubilite du mercure metallique dans les solvants organiques; Rastvorimost' metallicheskoj rtuti v organicheskikh rastvoritelyakh; Solubilidad del mercurio metalico en solventes organicos

    Energy Technology Data Exchange (ETDEWEB)

    Klehr, E H; Voigt, A F [Institute for Atomic Research and Department of Chemistry, Iowa State University, Ames, IA (United States)

    1962-03-15

    The solubilities of metallic mercury at 25{sup o}C in the solvents carbon tetrachloride, 2, 2, 4-trimethylpentane, n-decane, benzene, toluene, nitrobenzene, chlorobenzene and bromobenzene have been determined by the use of Hg{sup 203} tracer. Measurements were made either by shaking mercury metal of known specific activity with the solvent, or by measuring the distribution coefficient of the metal between the solvent and water and combining this measurement with the solubility of mercury in water, or by both methods. Radioactivity was measured by counting precipitated samples with a GM counter or liquid aliquots with a well-type scintillator counter. All solubilities were in the range (4.6 to 16) x 10{sup -6} g atoms/l. For n-decane, toluene and chlorobenzene, the temperature dependence of the solubility was determined over the range 0 to 45{sup o}C. The Hildebrand-Scott theory of solubility has been applied to these systems for comparison. For the aliphatic hydrocarbons, the solubilities predicted by theory are within 35% of those observed, but for the other solvents, the predicted values are 4 to 18 times larger than those observed. Modification of the theory gives better agreement for some solvents but poorer agreement for others. Curves of log G (solubility) vs. 1/T were straight lines with slopes similar to those obtained from the Hildebrand-Scott theory but displaced from those curves. The slopes of the curves were used for the calculation of heats and entropies of solution. Entropies were also calculated from curves of log G vs. log T. The two sets of entropy values were in agreement with each other and were within one to four entropy units of the ideal entropies of mixing. (author) [French] Les auteurs ont determine la solubilite du mercure metallique a 25{sup o}C dans les solvants suivants: tetrachlorure de carbone, trimethylpentane 2, 2, 4, n-decane, benzene, toluene, nitrobenzene, chlorobenzene et bromobenzene en utilisant le mercure-203 comme

  14. Differential patterns of injury to the proximal tubule of renal cortical slices following in vitro exposure to mercuric chloride, potassium dichromate, or hypoxic conditions.

    Science.gov (United States)

    Ruegg, C E; Gandolfi, A J; Nagle, R B; Brendel, K

    1987-09-15

    The innate susceptibility of renal cell types to these agents was investigated using precision-cut rabbit renal cortical slices made perpendicular to the cortical-papillary axis. Slices were incubated in DME/F12 medium containing 10 microM, 100 microM, or 1 mM concentrations of either metal for 12 hr or in Krebs-Hepes buffer gassed with nitrogen (100%) for 0.75 to 5 hr of hypoxic exposure. To simulate postischemic reperfusion, some slices were transferred to vessels gassed with oxygen after an initial hypoxic period. Mercuric chloride (100 microM) exposure resulted in damage to the straight regions of proximal tubules by 12 hr leaving convoluted regions unaffected. Hypoxia (2.25 hr) and potassium dichromate (100 microM for 12 hr) both caused injury to the convoluted proximal tubules without affecting straight proximal tubular regions. Mercury concentrations of 10 microM and 1 mM had no effect or injured all cell types within the slice, respectively. Similar results were observed for hypoxic periods less than 1.5 hr or greater than 3 hr of exposure. Potassium dichromate had no measurable affect at 10 microM, but at 1 mM focal lesions were observed after 4 hr of exposure, and by 12 hr all cell types within the slice were affected. Intracellular potassium content normalized to DNA correlated well, but always preceded the pathological lesions observed. These results demonstrate that injury to specific regions of the proximal tubule by these agents relates to an innate susceptibility of the intoxicated cell type independent of physiologic feedback or blood delivery patterns proposed as mechanisms of selective injury from in vivo studies.

  15. A conservative region of the mercuric reductase gene (merA) as a molecular marker of bacterial mercury resistance Região conservada do gene da mercúrio redutase (merA) como marcador molecular da resistência bacteriana ao mercúrio

    OpenAIRE

    Adriana Sotero-Martins; Michele Silva de Jesus; Michele Lacerda; Josino Costa Moreira; Ana Luzia Lauria Filgueiras; Paulo Rubens Guimarães Barrocas

    2008-01-01

    The most common bacterial mercury resistance mechanism is based on the reduction of Hg(II) to Hg0, which is dependent of the mercuric reductase enzyme (MerA) activity. The use of a 431 bp fragment of a conservative region of the mercuric reductase (merA) gene was applied as a molecular marker of this mechanism, allowing the identification of mercury resistant bacterial strains.O mecanismo de resistência bacteriana ao mercúrio mais comum é baseada na redução do Hg(II) a Hg0, através da ativida...

  16. Nuclear radiation detectors

    International Nuclear Information System (INIS)

    Kapoor, S.S.; Ramamurthy, V.S.

    1986-01-01

    The present monograph is intended to treat the commonly used detectors in the field of nuclear physics covering important developments of the recent years. After a general introduction, a brief account of interaction of radiation with matter relevant to the processes in radiation detection is given in Chapter II. In addition to the ionization chamber, proportional counters and Geiger Mueller counters, several gas-filled detectors of advanced design such as those recently developed for heavy ion physics and other types of studies have been covered in Chapter III. Semiconductor detectors are dealt with in Chapter IV. The scintillation detectors which function by sensing the photons emitted by the luminescence process during the interaction of the impinging radiation with the scintillation detector medium are described in Chapter V. The topic of neutron detectors is covered in Chapter VI, as in this case the emphasis is more on the method of neutron detection rather than on detector type. Electronic instrumentation related to signal pulse processing dealt with in Chapter VII. The track etch detectors based on the visualization of the track of the impinging charge particle have also been briefly covered in the last chapter. The scope of this monograph is confined to detectors commonly used in low and medium energy nuclear physics research and applications of nuclear techniques. The monograph is intended for post-graduate students and those beginning to work with the radiation detectors. (author)

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

    International Nuclear Information System (INIS)

    Darrouzet, E.; Marcellin, D.; Huc, S.; Quemeneur, E.; Pourcher, T.

    2006-01-01

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

  18. Detectors for Particle Radiation

    Science.gov (United States)

    Kleinknecht, Konrad

    1999-01-01

    This textbook provides a clear, concise and comprehensive review of the physical principles behind the devices used to detect charged particles and gamma rays, and the construction and performance of these many different types of detectors. Detectors for high-energy particles and radiation are used in many areas of science, especially particle physics and nuclear physics experiments, nuclear medicine, cosmic ray measurements, space sciences and geological exploration. This second edition includes all the latest developments in detector technology, including several new chapters covering micro-strip gas chambers, silicion strip detectors and CCDs, scintillating fibers, shower detectors using noble liquid gases, and compensating calorimeters for hadronic showers. This well-illustrated textbook contains examples from the many areas in science in which these detectors are used. It provides both a coursebook for students in physics, and a useful introduction for researchers in other fields.

  19. Silicon Telescope Detectors

    CERN Document Server

    Gurov, Yu B; Sandukovsky, V G; Yurkovski, J

    2005-01-01

    The results of research and development of special silicon detectors with a large active area ($> 8 cm^{2}$) for multilayer telescope spectrometers (fulfilled in the Laboratory of Nuclear Problems, JINR) are reviewed. The detector parameters are listed. The production of totally depleted surface barrier detectors (identifiers) operating under bias voltage two to three times higher than depletion voltage is described. The possibility of fabrication of lithium drifted counters with a very thin entrance window on the diffusion side of the detector (about 10--20 $\\mu$m) is shown. The detector fabrication technique has allowed minimizing detector dead regions without degradation of their spectroscopic characteristics and reliability during long time operation in charge particle beams.

  20. Physics of scintillation detectors

    International Nuclear Information System (INIS)

    Novotny, R.

    1991-01-01

    The general concept of a radiation detector is based on three fundamental principles: sensitivity of the device to the radiation of interest which requires a large cross-section in the detector material, detector response function to the physical properties of the radiation. As an example, a scintillation detector for charged particles should allow to identify the charge of the particle, its kinetic energy and the time of impact combined with optimum resolutions. Optimum conversion of the detector response (like luminescence of a scintillator) into electronical signals for further processing. The following article will concentrate on the various aspects of the first two listed principles as far as they appear to be relevant for photon and charged particle detection using organic and inorganic scintillation detectors. (orig.)