Materials Characteristics and Surface Morphology of a Cesium Iodide Coated Carbon Velvet Cathode (POSTPRINT)

DTIC Science & Technology

2009-03-31

cathodes consist of an array of carbon fibers pyrolytically bonded to a carbon substrate. The fibers then receive a CsI coating using either a...the oil side of the vacuum interface along the cathode shank. Current transformers provide current measurements of the cathode current, again

Slow hot carrier cooling in cesium lead iodide perovskites

NASA Astrophysics Data System (ADS)

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.

Redox transformations and transport of cesium and iodine (-1, 0, +5) in oxidizing and reducing zones of a sand and gravel aquifer

USGS Publications Warehouse

Fox, P.M.; Kent, D.B.; Davis, J.A.

2010-01-01

Tracer tests were performed in distinct biogeochemical zones of a sand and gravel aquifer in Cape Cod, MA, to study the redox chemistry (I) and transport (Cs, I) of cesium and iodine in a field setting. Injection of iodide (I -) into an oxic zone of the aquifer resulted in oxidation of I - to molecular iodine (I2) and iodate (IO3-) over transport distances of several meters. Oxidation is attributed to Mn-oxides present in the sediment. Transport of injected IO 3- and Cs+ was retarded in the mildly acidic oxic zone, with retardation factors of 1.6-1.8 for IO3- and 2.3-4.4for Cs. Cs retardation was likely due to cation exchange reactions. Injection of IO3- into a Fe-reducing zone of the aquifer resulted in rapid and complete reduction to I- within 3 m of transport. The nonconservative behavior of Cs and I observed during the tracer tests underscores the necessity of taking the redox chemistry of I as well as sorption properties of I species and Cs into account when predicting transport of radionuclides (e.g., 129I and 137Cs) in the environment.

Removal efficiency of water purifier and adsorbent for iodine, cesium, strontium, barium and zirconium in drinking water.

PubMed

Sato, Itaru; Kudo, Hiroaki; Tsuda, Shuji

2011-01-01

The severe incident of Fukushima Daiichi Nuclear Power Station has caused radioactive contamination of environment including drinking water. Radioactive iodine, cesium, strontium, barium and zirconium are hazardous fission products because of the high yield and/or relatively long half-life. In the present study, 4 pot-type water purifiers and several adsorbents were examined for the removal effects on these elements from drinking water. Iodide, iodate, cesium and barium were removed by all water purifiers with efficiencies about 85%, 40%, 75-90% and higher than 85%, respectively. These efficiencies lasted for 200 l, which is near the recommended limits for use of filter cartridges, without decay. Strontium was removed with initial efficiencies from 70% to 100%, but the efficiencies were slightly decreased by use. Zirconium was removed by two models, but hardly removed by the other models. Synthetic zeolite A4 efficiently removed cesium, strontium and barium, but had no effect on iodine and zirconium. Natural zeolite, mordenite, removed cesium with an efficiency as high as zeolite A4, but the removal efficiencies for strontium and barium were far less than those of zeolite A4. Activated carbon had little removal effects on these elements. In case of radioactive contamination of tap water, water purifiers may be available for convenient decontamination of drinking water in the home.

Modeling fission product vapor transport in the Falcon facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shepherd, I.M.; Drossinos, Y.; Benson, C.G.

1995-05-01

An extensive database of aerosol Experiments exists and has been used for checking aerosol transport codes. Data for fission product vapor transport are harder to find. Some qualitative data are available, but the Falcon thermal gradient tube tests carried out at AEA Technology`s laboratories in Winfrith, England, mark the first serious attempt to provide a set of experiments suitable for the validation of codes that predict the transport and condensation of realistic mixtures of fission product vapors. Four of these have been analyzed to check how well the computer code VICTORIA can predict the most important phenomena. Of the fourmore » experiments studied, two are reference cases (FAL-17 and FAL-19), one is a case without boric acid (FAL-18), and the other is run in a reducing atmosphere (FAL-20). The results show that once the vapors condense onto aerosols, VICTORIA can predict their deposition rather well. The dominant mechanism is thermophoresis, and each element deposits with more or less the same deposition velocity. The behavior of the vapors is harder to interpret. Essentially, it is important to know the temperature at which each element condenses. It is clear from the measurements that this temperature changed from test to test-caused mostly by the different speciation as the composition of the carrier gas and the relative concentration of other fission products changed. Only in the test with a steam atmosphere and without boric acid was the assumption valid that most of the iodine is cesium iodide and most of the cesium is cesium hydroxide. In general, VICTORIA predicts that, with the exception of cesium, there will be less variation in the speciation-and, hence, variation in the deposition-between tests than is in fact observed. VICTORIA underpredicts the volatility of most elements, and this is partly a consequence of the ideal solution assumption and partly an overestimation of vapor/aerosol interactions.« less

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

NASA Astrophysics Data System (ADS)

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.

Biosorption behavior and mechanism of cesium-137 on Rhodosporidium fluviale strain UA2 isolated from cesium solution.

PubMed

Lan, Tu; Feng, Yue; Liao, Jiali; Li, Xiaolong; Ding, Congcong; Zhang, Dong; Yang, Jijun; Zeng, Junhui; Yang, Yuanyou; Tang, Jun; Liu, Ning

2014-08-01

In order to identify a more efficient biosorbent for (137)Cs, we have investigated the biosorption behavior and mechanism of (137)Cs on Rhodosporidium fluviale (R. fluviale) strain UA2, one of the dominant species of a fungal group isolated from a stable cesium solution. We observed that the biosorption of (137)Cs on R. fluviale strain UA2 was a fast and pH-dependent process in the solution composed of R. fluviale strain UA2 (5 g/L) and cesium (1 mg/L). While a Langmuir isotherm equation indicated that the biosorption of (137)Cs was a monolayer adsorption, the biosorption behavior implied that R. fluviale strain UA2 adsorbed cesium ions by electrostatic attraction. The TEM analysis revealed that cesium ions were absorbed into the cytoplasm of R. fluviale strain UA2 across the cell membrane, not merely fixed on the cell surface, which implied that a mechanism of metal uptake contributed largely to the cesium biosorption process. Moreover, PIXE and EPBS analyses showed that ion-exchange was another biosorption mechanism for the cell biosorption of (137)Cs, in which the decreased potassium ions were replaced by cesium ions. All the above results implied that the biosorption of (137)Cs on R. fluviale strain UA2 involved a two-step process. The first step is passive biosorption that cesium ions are adsorbed to cells surface by electrostatic attraction; after that, the second step is active biosorption that cesium ions penetrate the cell membrane and accumulate in the cytoplasm. Copyright © 2014 Elsevier Ltd. All rights reserved.

Optical effect of the contamination of infrared windows by the outgassing of materials in outer space

NASA Technical Reports Server (NTRS)

Silberman, E.

1975-01-01

The composition and evaporation rate of the outgassing of a space vehicle thermal control paint as a function of temperature were studied. A contamination chamber was designed, constructed, and tested. Samples of thermal control paint were tested to determine if heating to moderate temperatures causes them to release outgassing products which can be collected on a cooled cesium iodide window for identification by IR analysis. Results showed that outgassing of surfaces other than the sample was a problem. Spectral bands of the deposits collected were compared.

Iodide uptake by negatively charged clay interlayers?

PubMed

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.

Refractive field correctors for the Starlab ultraviolet telescope

NASA Technical Reports Server (NTRS)

Bottema, M.

1982-01-01

Field correctors for a one-meter, f/15 cassegrainian telescope were designed as part of a NASA-funded study of an astronomical obervatory on board of the Space Shuttle. By means of a Gasgoigne corrector and a biconcave field flattener, astigmatism and field curvature are corrected in a 0.6 deg field. Applicable wavelength ranges are limited by chromatic aberrations. The upper wavelength is selected to match a photocathode response limit. The lower wavelength limit is defined by a filter. Examples of usable wavelength ranges are: 210 nm - 1100 nm (multialkali photocathode, fused-silica corrector elements), 177 nm - 320 nm (cesium telluride photocathode, calcium fluoride correctors); and possibly 134 nm - 190 nm (cesium iodide photocathode, lithium fluoride correctors). Residual rms lateral color is smaller than 0.02 arc sec, and axial color is smaller than 0.25 arc sec (blur diameter at the ends of the wavelength range). The correctors introduce a small amount of coma. This is compensated by adjustment of the conic constants of the telescope mirrors.

Evaluation of quality-control data collected by the U.S. Geological Survey for routine water-quality activities at the Idaho National Laboratory and vicinity, southeastern Idaho, 2002-08

USGS Publications Warehouse

Rattray, Gordon W.

2014-01-01

Quality-control (QC) samples were collected from 2002 through 2008 by the U.S. Geological Survey, in cooperation with the U.S. Department of Energy, to ensure data robustness by documenting the variability and bias of water-quality data collected at surface-water and groundwater sites at and near the Idaho National Laboratory. QC samples consisted of 139 replicates and 22 blanks (approximately 11 percent of the number of environmental samples collected). Measurements from replicates were used to estimate variability (from field and laboratory procedures and sample heterogeneity), as reproducibility and reliability, of water-quality measurements of radiochemical, inorganic, and organic constituents. Measurements from blanks were used to estimate the potential contamination bias of selected radiochemical and inorganic constituents in water-quality samples, with an emphasis on identifying any cross contamination of samples collected with portable sampling equipment. The reproducibility of water-quality measurements was estimated with calculations of normalized absolute difference for radiochemical constituents and relative standard deviation (RSD) for inorganic and organic constituents. The reliability of water-quality measurements was estimated with pooled RSDs for all constituents. Reproducibility was acceptable for all constituents except dissolved aluminum and total organic carbon. Pooled RSDs were equal to or less than 14 percent for all constituents except for total organic carbon, which had pooled RSDs of 70 percent for the low concentration range and 4.4 percent for the high concentration range. Source-solution and equipment blanks were measured for concentrations of tritium, strontium-90, cesium-137, sodium, chloride, sulfate, and dissolved chromium. Field blanks were measured for the concentration of iodide. No detectable concentrations were measured from the blanks except for strontium-90 in one source solution and one equipment blank collected in September and October 2004, respectively. The detectable concentrations of strontium-90 in the blanks probably were from a small source of strontium-90 contamination or large measurement variability, or both. Order statistics and the binomial probability distribution were used to estimate the magnitude and extent of any potential contamination bias of tritium, strontium-90, cesium-137, sodium, chloride, sulfate, dissolved chromium, and iodide in water-quality samples. These statistical methods indicated that, with (1) 87 percent confidence, contamination bias of cesium-137 and sodium in 60 percent of water-quality samples was less than the minimum detectable concentration or reporting level; (2) 92‒94 percent confidence, contamination bias of tritium, strontium-90, chloride, sulfate, and dissolved chromium in 70 percent of water-quality samples was less than the minimum detectable concentration or reporting level; and (3) 75 percent confidence, contamination bias of iodide in 50 percent of water-quality samples was less than the reporting level for iodide. These results support the conclusion that contamination bias of water-quality samples from sample processing, storage, shipping, and analysis was insignificant and that cross-contamination of perched groundwater samples collected with bailers during 2002–08 was insignificant.

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

PubMed Central

2017-01-01

Metal halide perovskites such as methylammonium lead iodide (MAPbI3) are highly promising materials for photovoltaics. However, the relationship between the organic nature of the cation and the optoelectronic quality remains debated. In this work, we investigate the optoelectronic properties of fully inorganic vapour-deposited and spin-coated black-phase CsPbI3 thin films. Using the time-resolved microwave conductivity technique, we measure charge carrier mobilities up to 25 cm2/(V s) and impressively long charge carrier lifetimes exceeding 10 μs for vapour-deposited CsPbI3, while the carrier lifetime reaches less than 0.2 μs in the spin-coated samples. Finally, we show that these improved lifetimes result in enhanced device performance with power conversion efficiencies close to 9%. Altogether, these results suggest that the charge carrier mobility and recombination lifetime are mainly dictated by the inorganic framework rather than the organic nature of the cation. PMID:28852710

Highly Efficient Spectrally Stable Red Perovskite Light-Emitting Diodes.

PubMed

Tian, Yu; Zhou, Chenkun; Worku, Michael; Wang, Xi; Ling, Yichuan; Gao, Hanwei; Zhou, Yan; Miao, Yu; Guan, Jingjiao; Ma, Biwu

2018-05-01

Perovskite light-emitting diodes (LEDs) have recently attracted great research interest for their narrow emissions and solution processability. Remarkable progress has been achieved in green perovskite LEDs in recent years, but not blue or red ones. Here, highly efficient and spectrally stable red perovskite LEDs with quasi-2D perovskite/poly(ethylene oxide) (PEO) composite thin films as the light-emitting layer are reported. By controlling the molar ratios of organic salt (benzylammonium iodide) to inorganic salts (cesium iodide and lead iodide), luminescent quasi-2D perovskite thin films are obtained with tunable emission colors from red to deep red. The perovskite/polymer composite approach enables quasi-2D perovskite/PEO composite thin films to possess much higher photoluminescence quantum efficiencies and smoothness than their neat quasi-2D perovskite counterparts. Electrically driven LEDs with emissions peaked at 638, 664, 680, and 690 nm have been fabricated to exhibit high brightness and external quantum efficiencies (EQEs). For instance, the perovskite LED with an emission peaked at 680 nm exhibits a brightness of 1392 cd m -2 and an EQE of 6.23%. Moreover, exceptional electroluminescence spectral stability under continuous device operation has been achieved for these red perovskite LEDs. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ab initio study of the effects of thin CsI coatings on the work function of graphite cathodes

NASA Astrophysics Data System (ADS)

Vlahos, Vasilios; Booske, John H.; Morgan, Dane

2007-10-01

Cesium-iodide (CsI)-coated graphite cathodes are promising electron sources for high power microwave generators, but the mechanism driving the improved emission is not well understood. Therefore, an ab initio modeling investigation on the effects of thin CsI coatings on graphite has been carried out. It is demonstrated that the CsI coatings reduce the work function of the system significantly through a mechanism of induced dipoles. The results suggest that work function modification is a major contribution to the improved emission seen when CsI coatings are applied to C.

Cu(I)-Catalyzed Pentafluoroethylation of Aryl Iodides in the Presence of Tetrafluoroethylene and Cesium Fluoride: Determining the Route to Key Pentafluoroethyl Cu(I) Intermediate.

PubMed

Ohashi, Masato; Ishida, Naoyoshi; Ando, Kota; Hashimoto, Yu; Shigaki, Anna; Kikushima, Kotaro; Ogoshi, Sensuke

2018-05-16

The Cu(I)-catalyzed pentafluoroethylation of iodoarenes via the fluorocupration of tetrafluoroethylene (TFE) is disclosed. The active species, (phen)CuC₂F₅, was isolated and its molecular structure confirmed by a single-crystal X-ray diffraction analysis. The key to the successful suppression of the competing oligomerization of TFE is to refrain from stirring the reaction mixture. A mechanistic study clearly discarded the possibility that the catalytic reaction proceeds via a radical pathway. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Metal cluster's effect on the optical properties of cesium bromide thin films

NASA Astrophysics Data System (ADS)

Kumar, Kuldeep; Arun, P.; Ravi Kant, Chhaya; Juluri, Bala Krishna

2012-06-01

Cesium bromide (CsBr) films grown on glass substrates by thermal evaporation showed prominent absorption peaks in the UV-visible region. Interestingly, these absorption spectra showed peaks which red shifted over time in ambient exposure. Structural and morphological studies suggested decrease in particle size overtime which was unusual. Electron micrographs show the formation of "daughter" cesium nanorods from parent CsBr particles. Theoretical calculations show the optical behavior observed to be due to localized surface plasmon resonance resulting from cesium nanorods.

Physical barrier effect of geopolymeric waste form on diffusivity of cesium and strontium.

PubMed

Jang, J G; Park, S M; Lee, H K

2016-11-15

The present study investigates the physical barrier effect of geopolymeric waste form on leaching behavior of cesium and strontium. Fly ash-based geopolymers and slag-blended geopolymers were used as solidification agents. The leaching behavior of cesium and strontium from geopolymers was evaluated in accordance with ANSI/ANS-16.1. The diffusivity of cesium and strontium in a fly ash-based geopolymer was lower than that in Portland cement by a factor of 10(3) and 10(4), respectively, showing significantly improved immobilization performance. The leaching resistance of fly ash-based geopolymer was relatively constant regardless of the type of fly ash. The diffusivity of water-soluble cesium and strontium ions were highly correlated with the critical pore diameter of the binder. The critical pore diameter of the fly ash-based geopolymer was remarkably smaller than those of Portland cement and slag-blended geopolymer; consequently, its ability physically to retard the diffusion of nuclides (physical barrier effect) was superior. Copyright © 2016 Elsevier B.V. All rights reserved.

Desorption of radioactive cesium by seawater from the suspended particles in river water.

PubMed

Onodera, Masaki; Kirishima, Akira; Nagao, Seiya; Takamiya, Kouichi; Ohtsuki, Tsutomu; Akiyama, Daisuke; Sato, Nobuaki

2017-10-01

In 2011, the accident at the Fukushima-Daiichi nuclear power plant dispersed radioactive cesium throughout the environment, contaminating the land, rivers, and sea. Suspended particles containing clay minerals are the transportation medium for radioactive cesium from rivers to the ocean because cesium is strongly adsorbed between the layers of clay minerals, forming inner sphere complexes. In this study, the adsorption and desorption behaviors of radioactive cesium from suspended clay particles in river water have been investigated. The radioactive cesium adsorption and desorption experiments were performed with two kinds of suspended particulate using a batch method with 137 Cs tracers. In the cesium adsorption treatment performed before the desorption experiments, simulated river water having a total cesium concentration ([ 133+137 Cs + ] total ) of 1.3 nM (10 -9  mol/L) was used. The desorption experiments were mainly conducted at a solid-to-liquid ratio of 0.17 g/L. The desorption agents were natural seawater collected at 10 km north of the Fukushima-Daiichi nuclear power plant, artificial seawater, solutions of NaCl, KCl, NH 4 Cl, and 133 CsCl, and ultrapure water. The desorption behavior, which depends on the preloaded cesium concentration in the suspended particles, was also investigated. Based on the cesium desorption experiments using suspended particles, which contained about 1000 ng/g loaded cesium, the order of cesium desorption ratios for each desorption agent was determined as 1 M NaCl (80%) > 470 mM NaCl (65%) > 1 M KCl (30%) ≈ seawater (natural seawater and Daigo artificial seawater) > 1 M NH 4 Cl (20%) > 1 M 133 CsCl (15%) ≫ ultrapure water (2%). Moreover, an interesting result was obtained: The desorption ratio in the 470 mM NaCl solution was much higher than that in seawater, even though the Na + concentrations were identical. These results indicate that the cesium desorption mechanism is not a simple ion exchange reaction but is strongly related to structural changes in the clay minerals in the suspended particles. Hydrated Na + ions expand the interlayer distance of the clay minerals, resulting in the facile desorption of cesium; in contrast, dehydrated K + ions reduce the interlayer distance and inhibit the desorption of cesium. In conclusion, the desorption of cesium from the suspended particles is controlled by the presence of sodium and potassium ions and the preloaded cesium concentration in the suspended particles. Copyright © 2017 Elsevier Ltd. All rights reserved.

An aerial radiological survey of the Robert Emmett Ginna Nuclear Power Plant and surrounding area, Ontario, New York

DOE Office of Scientific and Technical Information (OSTI.GOV)

Proctor, A.E.

1997-06-01

Terrestrial radioactivity surrounding the Robert Emmett Ginna Nuclear Power Plant was measured using aerial radiological surveying techniques. The purpose of this survey was to document exposure rates near the plant and to identify unexpected, man-made radiation sources within the survey area. The surveyed area included land areas within a three-mile radius of the plant site. Data were acquired using an airborne detection system that employed sodium iodide, thallium-activated detectors. Exposure-rate and photopeak counts were computed from these data and plotted on aerial photographs of the survey area. Several ground-based exposure measurements were made for comparison with the aerial survey results.more » Exposure rates in the area surrounding the plant site varied from 6 to 10 microroentgens per hour. Man-made radiation (cobalt-60 within the plant site and cesium-1 37 directly over the reactor) was found at the plant site. In addition, small areas of suspected cesium-137 activity were found within the survey areas. Other than these small sites, the survey area was free of man-made radioac- tivity.« less

Development of Scintillators in Nuclear Medicine.

PubMed

Khoshakhlagh, Mohammad; Islamian, Jalil Pirayesh; Abedi, Seyed Mohammad; Mahmoudian, Babak

2015-01-01

High-quality image is necessary for accurate diagnosis in nuclear medicine. There are many factors in creating a good image and detector is the most important one. In recent years, several detectors are studied to get a better picture. The aim of this paper is comparison of some type of these detectors such as thallium activated sodium iodide bismuth germinate cesium activated yttrium aluminum garnet (YAG: Ce) YAP: Ce "lutetium aluminum garnet activated by cerium" CRY018 "CRY019" lanthanum bromide and cadmium zinc telluride. We studied different properties of these crystals including density, energy resolution and decay times that are more important factors affecting the image quality.

Development of Scintillators in Nuclear Medicine

PubMed Central

Khoshakhlagh, Mohammad; Islamian, Jalil Pirayesh; Abedi, Seyed Mohammad; Mahmoudian, Babak

2015-01-01

High-quality image is necessary for accurate diagnosis in nuclear medicine. There are many factors in creating a good image and detector is the most important one. In recent years, several detectors are studied to get a better picture. The aim of this paper is comparison of some type of these detectors such as thallium activated sodium iodide bismuth germinate cesium activated yttrium aluminum garnet (YAG: Ce) YAP: Ce “lutetium aluminum garnet activated by cerium” CRY018 “CRY019” lanthanum bromide and cadmium zinc telluride. We studied different properties of these crystals including density, energy resolution and decay times that are more important factors affecting the image quality. PMID:26420984

High-Performance CH3NH3PbI3-Inverted Planar Perovskite Solar Cells with Fill Factor Over 83% via Excess Organic/Inorganic Halide.

PubMed

Jahandar, Muhammad; Khan, Nasir; Lee, Hang Ken; Lee, Sang Kyu; Shin, Won Suk; Lee, Jong-Cheol; Song, Chang Eun; Moon, Sang-Jin

2017-10-18

The reduction of charge carrier recombination and intrinsic defect density in organic-inorganic halide perovskite absorber materials is a prerequisite to achieving high-performance perovskite solar cells with good efficiency and stability. Here, we fabricated inverted planar perovskite solar cells by incorporation of a small amount of excess organic/inorganic halide (methylammonium iodide (CH 3 NH 3 I; MAI), formamidinium iodide (CH(NH 2 ) 2 I; FAI), and cesium iodide (CsI)) in CH 3 NH 3 PbI 3 perovskite film. Larger crystalline grains and enhanced crystallinity in CH 3 NH 3 PbI 3 perovskite films with excess organic/inorganic halide reduce the charge carrier recombination and defect density, leading to enhanced device efficiency (MAI+: 14.49 ± 0.30%, FAI+: 16.22 ± 0.38% and CsI+: 17.52 ± 0.56%) compared to the efficiency of a control MAPbI 3 device (MAI: 12.63 ± 0.64%) and device stability. Especially, the incorporation of a small amount of excess CsI in MAPbI 3 perovskite film leads to a highly reproducible fill factor of over 83%, increased open-circuit voltage (from 0.946 to 1.042 V), and short-circuit current density (from 18.43 to 20.89 mA/cm 2 ).

Charged Particle Monitor on the Astrosat Mission

NASA Astrophysics Data System (ADS)

Rao, A. R.; Patil, M. H.; Bhargava, Yash; Khanna, Rakesh; Hingar, M. K.; Kutty, A. P. K.; Malkar, J. P.; Basak, Rupal; Sreekumar, S.; Samuel, Essy; Priya, P.; Vinod, P.; Bhattacharya, D.; Bhalerao, V.; Vadawale, S. V.; Mithun, N. P. S.; Pandiyan, R.; Subbarao, K.; Seetha, S.; Sarma, K. Suryanarayana

2017-06-01

Charged Particle Monitor (CPM) on-board the Astrosat satellite is an instrument designed to detect the flux of charged particles at the satellite location. A Cesium Iodide Thallium (CsI(Tl)) crystal is used with a Kapton window to detect protons with energies greater than 1 MeV. The ground calibration of CPM was done using gamma-rays from radioactive sources and protons from particle accelerators. Based on the ground calibration results, energy deposition above 1 MeV are accepted and particle counts are recorded. It is found that CPM counts are steady and the signal for the onset and exit of South Atlantic Anomaly (SAA) region are generated in a very reliable and stable manner.

Characteristics of cesium iodide for use as a particle discriminator for high energy cosmic rays

NASA Technical Reports Server (NTRS)

Crannell, C. J.; Kurz, R. J.; Viehmann, W.

1973-01-01

The possible use of CsI to discriminate between high energy cosmic ray electrons and interacting protons has been investigated. The pulse-shape properties as a function of ionization density, temperature, and spectral response are presented for thallium-activated CsI and as a function of ionization density for sodium-activated CsI. The results are based on previously published data and on corroborative measurements from the present work. Experimental results on the response of CsI to electron-induced electromagnetic cascades and to interacting hadrons are described. Bibliographies of publications dealing with the properties of CsI and with pulse-shape discrimination techniques are presented.

Small-angle neutron scattering study of the structure of mixed micellar solutions based on heptaethylene glycol monotetradecyl ether and cesium dodecyl sulfate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rajewska, A., E-mail: aldonar@jinr.ru; Medrzycka, K.; Hallmann, E.

2016-01-15

The micellization in mixed aqueous systems based on a nonionic surfactant, heptaethylene glycol monotetradecyl ether (C{sub 14}E{sub 7}), and an anionic surfactant, cesium dodecyl sulfate, has been investigated by small-angle neutron scattering. Preliminary data on the behavior of the C{sub 14}E{sub 7} aqueous solutions (with three concentrations, 0.17, 0.5, and 1%) mixed with a small amount of anionic surfactant, cesium dodecyl sulfate, are reported.

Cesium-induced inhibition of bacterial growth of Pseudomonas aeruginosa PAO1 and their possible potential applications for bioremediation of wastewater.

PubMed

Kang, Sung-Min; Jang, Sung-Chan; Heo, Nam Su; Oh, Seo Yeong; Cho, Hye-Jin; Rethinasabapathy, Muruganantham; Vilian, A T Ezhil; Han, Young-Kyu; Roh, Changhyun; Huh, Yun Suk

2017-09-15

Radioactive isotopes and fission products have attracted considerable attention because of their long lasting serious damage to the health of humans and other organisms. This study examined the toxicity and accumulation behavior of cesium towards P. aeruginosa PAO1 and its capacity to remove cesium from waste water. Interestingly, the programmed bacterial growth inhibition occurred according to the cesium environment. The influence of cesium was analyzed using several optical methods for quantitative evaluation. Cesium plays vital role in the growth of microorganisms and functions as an anti-microbial agent. The toxicity of Cs to P. aeruginosa PAO1 increases as the concentration of cesium is increased in concentration-dependent manner. P. aeruginosa PAO1 shows excellent Cs removal efficiency of 76.1% from the contaminated water. The toxicity of cesium on the cell wall and in the cytoplasm were studied by transmission electron microscopy and electron dispersive X-ray analysis. Finally, the removal of cesium from wastewater using P. aeruginosa PAO1 as a potential biosorbent and the blocking of competitive interactions of other monovalent cation, such as potassium, were assessed. Overall, P. aeruginosa PAO1 can be used as a high efficient biomaterial in the field of radioactive waste disposal and management. Copyright © 2017 Elsevier B.V. All rights reserved.

Solid-state detector system for measuring concentrations of tritiated water vapour and other radioactive gases

NASA Astrophysics Data System (ADS)

Nunes, J. C.; Surette, R. A.; Wood, M. J.

1999-08-01

A detector system was built using a silicon photodiode plus preamplifier and a cesium iodide scintillator plus preamplifier that were commercially available. The potential of the system for measuring concentrations of tritiated water vapour in the presence of other radioactive sources was investigated. For purposes of radiation protection, the sensitivity of the detector system was considered too low for measuring tritiated water vapour concentrations in workplaces such as nuclear power plants. Nevertheless, the spectrometry capability of the system was used successfully to differentiate amongst some radioactive gases in laboratory tests. Although this relatively small system can measure radioactive noble gases as well as tritiated water vapour concentrations, its response to photons remains an issue.

Internal calibration on adjacent samples (InCAS) with Fourier transform mass spectrometry.

PubMed

O'Connor, P B; Costello, C E

2000-12-15

Using matrix-assisted laser desorption/ionization (MAL DI) on a trapped ion mass spectrometer such as a Fourier transform mass spectrometer (FTMS) allows accumulation of ions in the cell from multiple laser shots prior to detection. If ions from separate MALDI samples are accumulated simultaneously in the cell, ions from one sample can be used to calibrate ions from the other sample. Since the ions are detected simultaneously in the cell, this is, in effect, internal calibration, but there are no selective desorption effects in the MALDI source. This method of internal calibration with adjacent samples is demonstrated here on cesium iodide clusters, peptides, oligosaccharides, poly(propylene glycol), and fullerenes and provides typical FTMS internal calibration mass accuracy of < 1 ppm.

Supercoiled circular DNA of an insect granulosis virus

PubMed Central

Tweeten, Kathleen A.; Bulla, Lee A.; Consigli, Richard A.

1977-01-01

The DNA of the granulosis virus of the Indian meal moth, Plodia interpunctella, was characterized by physical chemical and electron microscopic techniques. Twenty-five percent of the DNA extracted from purified virus was isolated as supercoiled circular molecules. The remaining 75% consisted of relaxed circular molecules. These molecular forms were indicated by the production of two radioactive bands during sedimentation of 3H-labeled granulosis virus DNA in alkaline sucrose gradients or in equilibrium density gradients of neutral cesium chloride/propidium iodide. Electron microscopic visualization of the DNA that banded at the higher density in the latter gradients revealed supercoiled structures whereas that of DNA that banded at the lower density demonstrated relaxed circular molecules. The superhelical molecules were converted to relaxed circles by treatment with pancreatic DNase. The molecular weight of the viral DNA was calculated to be 81 × 106 by sedimentation in neutral sucrose and 78 × 106 by sedimentation in alkaline sucrose. The molecular weight estimated from length measurements in electron micrographs was 76 × 106. The buoyant density of the granulosis virus DNA was 1.703 g/cm3 and that of its insect host DNA was 1.697 g/cm3. Equilibrium sedimentation in cesium chloride and thermal denaturation indicated G + C contents of 44% and 39% for the viral and host DNA, respectively. Images PMID:198791

Supercoiled circular DNA of an insect granulosis virus.

PubMed

Tweeten, K A; Bulla, L A; Consigli, R A

1977-08-01

The DNA of the granulosis virus of the Indian meal moth, Plodia interpunctella, was characterized by physical chemical and electron microscopic techniques. Twenty-five percent of the DNA extracted from purified virus was isolated as supercoiled circular molecules. The remaining 75% consisted of relaxed circular molecules. These molecular forms were indicated by the production of two radioactive bands during sedimentation of (3)H-labeled granulosis virus DNA in alkaline sucrose gradients or in equilibrium density gradients of neutral cesium chloride/propidium iodide. Electron microscopic visualization of the DNA that banded at the higher density in the latter gradients revealed supercoiled structures whereas that of DNA that banded at the lower density demonstrated relaxed circular molecules. The superhelical molecules were converted to relaxed circles by treatment with pancreatic DNase. The molecular weight of the viral DNA was calculated to be 81 x 10(6) by sedimentation in neutral sucrose and 78 x 10(6) by sedimentation in alkaline sucrose. The molecular weight estimated from length measurements in electron micrographs was 76 x 10(6). The buoyant density of the granulosis virus DNA was 1.703 g/cm(3) and that of its insect host DNA was 1.697 g/cm(3). Equilibrium sedimentation in cesium chloride and thermal denaturation indicated G + C contents of 44% and 39% for the viral and host DNA, respectively.

INVESTIGATIONS ON THE BIOLOGICAL BEHAVIOR OF RADIOACTIVE FISSION PRODUCTS IN PREGNANT ANIMALS. III. ENRICHMENT OF RADIOCESIUM IN NURSING RATS AND THE MODIFICATION OF THE Cs RETENTION IN ORGANS OF THE MOTHER DURING THE LACTATION PERIOD (in German)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kriegel, H.; Weber, E.

In a continuation of the investigation on the placental turnover of radiocesium in the rat, the changes of the postpartum cesium content in the young nursing animals caused by the amounts of cesium, which are excreted with the mother-milk, are described. The cesium content in the organs of the mother at the end of the lactation period is decreased by 50% in contrast to the un- pregnant controls. (auth)

Work function measurements during plasma exposition at conditions relevant in negative ion sources for the ITER neutral beam injection.

PubMed

Gutser, R; Wimmer, C; Fantz, U

2011-02-01

Cesium seeded sources for surface generated negative hydrogen ions are major components of neutral beam injection systems in future large-scale fusion experiments such as ITER. The stability and delivered current density depend highly on the work function during vacuum and plasma phases of the ion source. One of the most important quantities that affect the source performance is the work function. A modified photocurrent method was developed to measure the temporal behavior of the work function during and after cesium evaporation. The investigation of cesium exposed Mo and MoLa samples under ITER negative hydrogen ion based neutral beam injection relevant surface and plasma conditions showed the influence of impurities which result in a fast degradation when the plasma exposure or the cesium flux onto the sample is stopped. A minimum work function close to that of bulk cesium was obtained under the influence of the plasma exposition, while a significantly higher work function was observed under ITER-like vacuum conditions.

A Study of the Hydration of the Alkali Metal Ions in Aqueous Solution

PubMed Central

2011-01-01

The hydration of the alkali metal ions in aqueous solution has been studied by large angle X-ray scattering (LAXS) and double difference infrared spectroscopy (DDIR). The structures of the dimethyl sulfoxide solvated alkali metal ions in solution have been determined to support the studies in aqueous solution. The results of the LAXS and DDIR measurements show that the sodium, potassium, rubidium and cesium ions all are weakly hydrated with only a single shell of water molecules. The smaller lithium ion is more strongly hydrated, most probably with a second hydration shell present. The influence of the rubidium and cesium ions on the water structure was found to be very weak, and it was not possible to quantify this effect in a reliable way due to insufficient separation of the O–D stretching bands of partially deuterated water bound to these metal ions and the O–D stretching bands of the bulk water. Aqueous solutions of sodium, potassium and cesium iodide and cesium and lithium hydroxide have been studied by LAXS and M–O bond distances have been determined fairly accurately except for lithium. However, the number of water molecules binding to the alkali metal ions is very difficult to determine from the LAXS measurements as the number of distances and the temperature factor are strongly correlated. A thorough analysis of M–O bond distances in solid alkali metal compounds with ligands binding through oxygen has been made from available structure databases. There is relatively strong correlation between M–O bond distances and coordination numbers also for the alkali metal ions even though the M–O interactions are weak and the number of complexes of potassium, rubidium and cesium with well-defined coordination geometry is very small. The mean M–O bond distance in the hydrated sodium, potassium, rubidium and cesium ions in aqueous solution have been determined to be 2.43(2), 2.81(1), 2.98(1) and 3.07(1) Å, which corresponds to six-, seven-, eight- and eight-coordination. These coordination numbers are supported by the linear relationship of the hydration enthalpies and the M–O bond distances. This correlation indicates that the hydrated lithium ion is four-coordinate in aqueous solution. New ionic radii are proposed for four- and six-coordinate lithium(I), 0.60 and 0.79 Å, respectively, as well as for five- and six-coordinate sodium(I), 1.02 and 1.07 Å, respectively. The ionic radii for six- and seven-coordinate K+, 1.38 and 1.46 Å, respectively, and eight-coordinate Rb+ and Cs+, 1.64 and 1.73 Å, respectively, are confirmed from previous studies. The M–O bond distances in dimethyl sulfoxide solvated sodium, potassium, rubidium and cesium ions in solution are very similar to those observed in aqueous solution. PMID:22168370

A Study of the quality of CsI detectors and pulse-shape discrimination of scintillators for ?[U+0251]-particles, ?[U+0263]-particles, and neutrons

NASA Astrophysics Data System (ADS)

Salyer, Kaitlin; Rogachev, Grigory; Hooker, Joshua

2016-09-01

This project studied the capabilities of two different scintillators, Cesium Iodide (CsI) and p-Terphenyl. First, the resolution of a CsI detector was investigated by exposing only very small areas of its surface at a time to an alpha source. Second, the abilities of p-Terphenyl to detect alpha particles, gamma particles, and neutrons were analyzed through pulse shape discrimination. p-Terphenyl is of particular interest because it will be used in the Mitchell Institute Neutrino Experiment at Reactor (MINER) at Texas A&M University for measuring background data. The information learned from conducting these tests will be useful in understanding and expanding the limits of the experiments in which these detectors will ultimately be used.

An NMR thermometer for cryogenic magic-angle spinning NMR: The spin-lattice relaxation of 127I in cesium iodide

NASA Astrophysics Data System (ADS)

Sarkar, Riddhiman; Concistrè, Maria; Johannessen, Ole G.; Beckett, Peter; Denning, Mark; Carravetta, Marina; al-Mosawi, Maitham; Beduz, Carlo; Yang, Yifeng; Levitt, Malcolm H.

2011-10-01

The accurate temperature measurement of solid samples under magic-angle spinning (MAS) is difficult in the cryogenic regime. It has been demonstrated by Thurber et al. (J. Magn. Reson., 196 (2009) 84-87) [10] that the temperature dependent spin-lattice relaxation time constant of 79Br in KBr powder can be useful for measuring sample temperature under MAS over a wide temperature range (20-296 K). However the value of T1 exceeds 3 min at temperatures below 20 K, which is inconveniently long. In this communication, we show that the spin-lattice relaxation time constant of 127I in CsI powder can be used to accurately measure sample temperature under MAS within a reasonable experimental time down to 10 K.

Improvements to the Hunter Dose tracking system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whiteside, T. S.; Aucott, T. J.; Brand, A. D.

Since 1965, the Savannah River Site (SRS) has conducted deer hunts which are open to the general public. SRS performs field monitoring for cesium-137 (Cs-137) of each harvested animal to determine whether the animal may be released to the hunter. A new field system for measuring Cs-137 in the harvested animals has been developed. The system incorporates numerous enhancements compared to the original system. The original system was composed of two Ludlum Measurements scalar-driven 2 inch x 2 inch sodium iodide counters, while the new system is based on a single Ametek Ortec Digibase-driven 2 inch x 4 inch xmore » 16 inch sodium iodide gamma spectrometer. The new system includes a series of easy-to-assemble stainless steel encapsulated lead shields. The combination of the larger detector size and lead shielding improved the detection limit of the new system by a factor of approximately three compared to the original system. This lower detection limit allows for a larger number of measurements to be directly compared to the laboratory results, in cases where animal portions have been sampled. The results from developing and using this system are presented as well as recommendations on improvements to the overall field monitoring of the SRS hunts.« less

Effects of Radiation and Temperature on Iodide Sorption by Surfactant-Modified Bentonite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choung, Sungwook; Kim, Min Kyung; Yang, Jungseok

2014-08-04

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

A study of environmental effects caused by cesium from ion thrusters

NASA Technical Reports Server (NTRS)

1971-01-01

The ATS-F satellite will carry two cesium ion thrusters. Cesium is a material that is not present in the upper atmosphere, and there is concern that the introduction of this material may result in some unexpected behavior. A study has been conducted to assess the magnitude of the effects that are to be expected. No observable effects were found as a result of the study. Consideration was given to the origin and destination of the material and the various reactions that could occur. The origin was considered to be anywhere in space from altitudes of about 100 km upward. The probable short term destination is in the form of cesium ions trapped in the earth's magnetic field or as ions and atoms in the heterosphere. The maximum possible number of cesium atoms in the field of view of an earth based observer is of the order of one million per square centimeter, far too few to be observable by visible, near-visible, or radio-frequency means. Further, no phenomena could be found that would result in the occurance of an observable event.

Mid-Award Progress Report for Department of Energy Office of Science Graduate Student Research Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoffman, M. K.

The purpose of the work proposed for this study is to investigate the behavior and transport mechanisms for cesium-137 in soils collected from contaminated sites with distinct source release scenarios. More specifically, this study aims to determine with which elements and minerals cesium-137 associates in these various environments to more reliably predict its migration in the subsurface. This will be achieved using a state-of-the-art analysis technique available at Lawrence Livermore National Laboratory (LLNL) known as NanoSIMS. Nano-scale secondary ion mass spectrometry, or NanoSIMS, is a destructive surface analysis technique in which positive secondary ions are generated from the surface ofmore » a sample and then quantified based on their mass-to-charge ratio (m/z) using mass spectrometry. The data collected about the secondary ions can then be used to create isotope-specific spatial maps with a resolution of a few hundred nanometers and depth profiles that show the variation of the secondary ion intensity with sputtering time. This should be an ideal technique for locating cesium-137 in a sample, as cesium is an easily ionized element, meaning the yield of secondary cesium (Cs) ions produced should be high and making the identification of cesium-137 straight forward.« less

Development and testing of the infrared interferometer spectrometer for the Mariner Mars 1971 spacecraft

NASA Technical Reports Server (NTRS)

Hanel, R. H.; Schlachman, B.; Vanous, D.; Rogers, D.; Taylor, J. H.

1971-01-01

The design, development and testing of the infrared interferometer spectrometer is reported with emphasis on the unique features of the Mariner instrument as compared to previous IRIS instruments flown on the Nimbus meteorological research satellites. The interferometer functions in the spectral range from 50 microns to 6.3 microns. A noise equivalent radiance of 0.5 X 10 to the -7th power W/sq cm/ster/cm has been achieved. Major improvements that were implemented included the cesium iodide beamsplitter and electronic features to suppress the effect of vibration on the Michelson mirror motion and digital filtering through the summation of increased sampling of the infrared signal. A bit error detection and correction scheme was also implemented in order to recover the science data with a higher level of confidence over the telecommunication link.

Testing iodized activated carbon filters with non-radioactive methyl iodide. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deitz, V.R.; Romans, J.B.

1980-05-30

Iodized carbons, impregnated with KIx(KI + xI2), were evaluated for trapping methyl iodide-127. In this method the complete effluent of the carbon is sampled and analyzed continuously. In contrast, the RDT-M16 test procedure counts the carbon and the back-up beds for the accumulated 131 species and no information is obtained for the interaction of the large amount of carrier methyl iodide-127 with the iodized charcoal. The test apparatus to measure the penetration of methyl iodide-127 is described and the calibration procedures are detailed. Results are given for the penetration of methyl iodide-127 through new activated carbons, carbons in service, andmore » exhausted carbons withdrawn from service. The reduction in trapping efficiency with service is accompanied by the development of a maximum in the concentration of methyl iodide-127 during the air purge after the dose period. This behavior has escaped notice with methyl iodide-131 due to the way that test is made. The chromatographic holdup of methyl iodide-127 by carbons in service, together with the subsequent slow desorption step, could result in a dilution of the penetration iodine to acceptable levels under some conditions encountered in plant filter operations.« less

Two halide-containing cesium manganese vanadates: synthesis, characterization, and magnetic properties

DOE PAGES

Smith Pellizzeri, Tiffany M.; McGuire, Michael A.; McMillen, Colin D.; ...

2018-01-24

In this study, two new halide-containing cesium manganese vanadates have been synthesized by a high-temperature (580 °C) hydrothermal synthetic method from aqueous brine solutions. One compound, Cs 3Mn(VO 3) 4Cl, (1) was prepared using a mixed cesium hydroxide/chloride mineralizer, and crystallizes in the polar noncentrosymmetric space group Cmm2, with a = 16.7820(8) Å, b = 8.4765(4) Å, c = 5.7867(3) Å. This structure is built from sinusoidal zig-zag (VO 3) n chains that run along the b-axis and are coordinated to Mn 2+ containing (MnO 4Cl) square-pyramidal units that are linked together to form layers. The cesium cations reside betweenmore » the layers, but also coordinate to the chloride ion, forming a cesium chloride chain that also propagates along the b-axis. The other compound, Cs 2Mn(VO 3) 3F, (2) crystallizes in space group Pbca with a = 7.4286(2) Å, b = 15.0175(5) Å, c = 19.6957(7) Å, and was prepared using a cesium fluoride mineralizer. The structure is comprised of corner sharing octahedral Mn 2+ chains, with trans fluoride ligands acting as bridging units, whose ends are capped by (VO 3) n vanadate chains to form slabs. The cesium atoms reside between the manganese vanadate layers, and also play an integral part in the structure, forming a cesium fluoride chain that runs along the b-axis. Both compounds were characterized by single-crystal X-ray diffraction, powder X-ray diffraction, and single-crystal Raman spectroscopy. Additionally, the magnetic properties of 2 were investigated. Lastly, above 50 K, it displays behavior typical of a low dimensional system with antiferromagnetic interactions, as to be expected for linear chains of manganese(II) within the crystal structure.« less

USSR Report, Life Sciences Biomedical and Behavioral Sciences

DTIC Science & Technology

1984-02-15

G. P. Somov; ZHURNAL MIKROBIOLOGII, EPIDEMIOLOGII I IMMUNOBIOLOGII, No 10, Oct 83) 12 Modern Preventive Measures for Zoonotic Infections (V. P...However, the concentrations of strontium-90 and cesium- 137 in the milk , potatoes and vegetables remained virtually unchanged in the period...covered, with the cesium-137/strontium-90 ratio ranging from 0.45 (carrots) to 2.75 ( milk ) in 1980, and from 0.55 (beets) to 4.0 ( milk ) in 1981. [130

CH3NH3PbI3 and CsPbI3 Supramolecular Clusters in 1D: Do They Evolve with the Same Principle of Cooperative Binding?

NASA Astrophysics Data System (ADS)

Varadwaj, Arpita; Varadwaj, Pradeep R.; Yamashita, Koichi

Development of novel semiconductor-based photo-catalytic and -voltaic systems is a major area of research in nanoscience and technologies, and engineering. The process can be either direct or indirect in converting the light energy into electricity. Some of the photovoltaics include the organic, dye-sensitized, and halide perovskite solar cells, among others. Methylammonium lead iodide (CH3NH3PbI3) inorganic-organic hybrid perovskite is one among the many highly valued semiconductors reported till date, comparable with the inorganic cesium lead iodide (CsPbI3) perovskite. These are competitive candidates in the solar energy race. Nevertheless, this study was concentrated on the fundamental understanding of the rational designs of the CH3NH3PbI3 and CsPbI3 supramolecular materials using first-principles calculations, emerged though the self-assembly of the respective building blocks. It therefore addresses the question whether the (CH3NH3PbI3)n and (CsPbI3)n (n =1-10) supramolecular clusters are the consequences of additivity, or non-additive cooperative binding? For addressing this question, the supramolecular properties such as the polarizability, the intermolecular charge transfer, and the binding energy, etc., all w.r.t the cluster size n, are exploited. CREST-JST, 7 Gobancho, Chiyoda-ku, Tokyo, Japan 102-0076.

Searching for dark absorption with direct detection experiments

DOE PAGES

Bloch, Itay M.; Essig, Rouven; Tobioka, Kohsaku; ...

2017-06-16

We consider the absorption by bound electrons of dark matter in the form of dark photons and axion-like particles, as well as of dark photons from the Sun, in current and next-generation direct detection experiments. Experiments sensitive to electron recoils can detect such particles with masses between a few eV to more than 10 keV. For dark photon dark matter, we update a previous bound based on XENON10 data and derive new bounds based on data from XENON100 and CDMSlite. We find these experiments to disfavor previously allowed parameter space. Moreover, we derive sensitivity projections for SuperCDMS at SNOLAB formore » silicon and germanium targets, as well as for various possible experiments with scintillating targets (cesium iodide, sodium iodide, and gallium arsenide). The projected sensitivity can probe large new regions of parameter space. For axion-like particles, the same current direction detection data improves on previously known direct-detection constraints but does not bound new parameter space beyond known stellar cooling bounds. However, projected sensitivities of the upcoming SuperCDMS SNOLAB using germanium can go beyond these and even probe parameter space consistent with possible hints from the white dwarf luminosity function. We find similar results for dark photons from the sun. For all cases, direct-detection experiments can have unprecedented sensitivity to dark-sector particles.« less

Searching for dark absorption with direct detection experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bloch, Itay M.; Essig, Rouven; Tobioka, Kohsaku

We consider the absorption by bound electrons of dark matter in the form of dark photons and axion-like particles, as well as of dark photons from the Sun, in current and next-generation direct detection experiments. Experiments sensitive to electron recoils can detect such particles with masses between a few eV to more than 10 keV. For dark photon dark matter, we update a previous bound based on XENON10 data and derive new bounds based on data from XENON100 and CDMSlite. We find these experiments to disfavor previously allowed parameter space. Moreover, we derive sensitivity projections for SuperCDMS at SNOLAB formore » silicon and germanium targets, as well as for various possible experiments with scintillating targets (cesium iodide, sodium iodide, and gallium arsenide). The projected sensitivity can probe large new regions of parameter space. For axion-like particles, the same current direction detection data improves on previously known direct-detection constraints but does not bound new parameter space beyond known stellar cooling bounds. However, projected sensitivities of the upcoming SuperCDMS SNOLAB using germanium can go beyond these and even probe parameter space consistent with possible hints from the white dwarf luminosity function. We find similar results for dark photons from the sun. For all cases, direct-detection experiments can have unprecedented sensitivity to dark-sector particles.« less

Environmental, Transient, Three-Dimensional, Hydrothermal, Mass Transport Code - FLESCOT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onishi, Yasuo; Bao, Jie; Glass, Kevin A.

The purpose of the project was to modify and apply the transient, three-dimensional FLESCOT code to be able to effectively simulate cesium behavior in Fukushima lakes/dam reservoirs, river mouths, and coastal areas. The ultimate objective of the FLESCOT simulation is to predict future changes of cesium accumulation in Fukushima area reservoirs and costal water. These evaluation results will assist ongoing and future environmental remediation activities and policies in a systematic and comprehensive manner.

Contrast-enhanced 3D micro-CT of plant tissues using different impregnation techniques.

PubMed

Wang, Zi; Verboven, Pieter; Nicolai, Bart

2017-01-01

X-ray micro-CT has increasingly been used for 3D imaging of plant structures. At the micrometer resolution however, limitations in X-ray contrast often lead to datasets with poor qualitative and quantitative measures, especially within dense cell clusters of plant tissue specimens. The current study developed protocols for delivering a cesium based contrast enhancing solution to varying plant tissue specimens for the purpose of improving 3D tissue structure characterization within plant specimens, accompanied by new image processing workflows to extract the additional data generated by the contrast enhanced scans. Following passive delivery of a 10% cesium iodide contrast solution, significant increases of 85.4 and 38.0% in analyzable cell volumes were observed in pear fruit hypanthium and tomato fruit outer mesocarp samples. A significant increase of 139.6% in the number of analyzable cells was observed in the pear fruit samples along the added ability to locate and isolate better brachysclereids and vasculature in the sample volume. Furthermore, contrast enhancement resulted in significant improvement in the definition of collenchyma and parenchyma in the petiolule of tomato leaflets, from which both qualitative and quantitative data can be extracted with respect to cell measures. However, contrast enhancement was not achieved in leaf vasculature and mesophyll tissue due to fundamental limitations. Active contrast delivery to apple fruit hypanthium samples did yield a small but insignificant increase in analyzable volume and cells, but data on vasculature can now be extracted better in correspondence to the pear hypanthium samples. Contrast delivery thus improved visualization and analysis the most in dense tissue types. The cesium based contrast enhancing protocols and workflows can be utilized to obtain detailed 3D data on the internal microstructure of plant samples, and can be adapted to additional samples of interest with minimal effort. The resulting datasets can therefore be utilized for more accurate downstream studies that requires 3D data.

0D-2D and 1D-2D Semiconductor Hybrids Composed of All Inorganic Perovskite Nanocrystals and Single-Layer Graphene with Improved Light Harvesting

DOE PAGES

Chen, Jia-Shiang; Doane, Tennyson L.; Li, Mingxing; ...

2017-12-27

In this study, inorganic cesium lead iodide (CsPbI 3) perovskite nanoparticles (PNPs) and perovskite nanowires (PNWs) with single-layer graphene (SLG) are combined to obtain 0D–2D PNP–SLG and 1D–2D PNW–SLG hybrids with improved light harvesting. Time-resolved single-nanostructure photoluminescence studies of PNPs, PNWs, and related hybrids reveal (i) quasi-two-state photoluminescence blinking in PNPs, (ii) highly polarized photoluminescence emitted by PNWs and (iii) efficient interfacial electron transfer between perovskite nanostructures and SLG in both PNP–SLG and PNW–SLG hybrids. Thus, doping of poorly absorbing, highly conductive SLG with perovskite nanocrystals and nanowires provides a simple, yet efficient path to obtain hybrids with increased light-harvestingmore » properties for potential utilization in the next-generation photodetectors and photovoltaic devices, including polarization sensitive photodetectors.« less

0D-2D and 1D-2D Semiconductor Hybrids Composed of All Inorganic Perovskite Nanocrystals and Single-Layer Graphene with Improved Light Harvesting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Jia-Shiang; Doane, Tennyson L.; Li, Mingxing

In this study, inorganic cesium lead iodide (CsPbI 3) perovskite nanoparticles (PNPs) and perovskite nanowires (PNWs) with single-layer graphene (SLG) are combined to obtain 0D–2D PNP–SLG and 1D–2D PNW–SLG hybrids with improved light harvesting. Time-resolved single-nanostructure photoluminescence studies of PNPs, PNWs, and related hybrids reveal (i) quasi-two-state photoluminescence blinking in PNPs, (ii) highly polarized photoluminescence emitted by PNWs and (iii) efficient interfacial electron transfer between perovskite nanostructures and SLG in both PNP–SLG and PNW–SLG hybrids. Thus, doping of poorly absorbing, highly conductive SLG with perovskite nanocrystals and nanowires provides a simple, yet efficient path to obtain hybrids with increased light-harvestingmore » properties for potential utilization in the next-generation photodetectors and photovoltaic devices, including polarization sensitive photodetectors.« less

Generation of CsI cluster ions for mass calibration in matrix-assisted laser desorption/ionization mass spectrometry.

PubMed

Lou, Xianwen; van Dongen, Joost L J; Meijer, E W

2010-07-01

A simple method was developed for the generation of cesium iodide (CsI) cluster ions up to m/z over 20,000 in matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). Calibration ions in both positive and negative ion modes can readily be generated from a single MALDI spot of CsI(3) with 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene] malononitrile (DCTB) matrix. The major cluster ion series observed in the positive ion mode is [(CsI)(n)Cs](+), and in the negative ion mode is [(CsI)(n)I](-). In both cluster series, ions spread evenly every 259.81 units. The easy method described here for the production of CsI cluster ions should be useful for MALDI MS calibrations. Copyright 2010 American Society for Mass Spectrometry. Published by Elsevier Inc. All rights reserved.

Moisture resistant and anti-reflection optical coatings produced by plasma polymerization of organic compounds

NASA Technical Reports Server (NTRS)

Hollahan, J. R.; Wydeven, T.

1975-01-01

The need for protective coatings on critical optical surfaces, such as halide crystal windows or lenses used in spectroscopy, has long been recognized. It has been demonstrated that thin, one micron, organic coatings produced by polymerization of flourinated monomers in low temperature gas discharge (plasma) exhibit very high degrees of moisture resistence, e.g., hundreds of hours protection for cesium iodide vs. minutes before degradation sets in for untreated surfaces. The index of refraction of these coatings is intermediate between that of the halide substrate and air, a condition for anti-reflection, another desirable property of optical coatings. Thus, the organic coatings not only offer protection, but improved transmittance as well. The polymer coating is non-absorbing over the range 0.4 to 40 microns with an exception at 8.0 microns, the expected absorption for C-F bonds.

The Role of Chromohalobacter on Transport of Lanthanides and Cesium in the Dolomite Mineral System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zengotita, Frances; Emerson, Hilary Palmer; Dittrich, Timothy M.

2017-12-01

The chemical behavior of actinide series elements and fission products is a concern for the Waste Isolation Pilot Plant repository due to their uncertain mobility in the subsurface salt formation. In this work, we are observing the behavior of the halophilic bacterium, Chromohalobacter, and its effect on the mobility of lanthanides and cesium in the presence of dolomite. Batch and minicolumn experiments were conducted with Cs + and lanthanides (Nd 3+, Eu 3+) to quantify potential transport with bacteria. Preliminary results show that Cs does not interact strongly with dolomite or Chromohalobacter, while the lanthanides can interact strongly with bothmore » minerals and bacteria depending on which the Ln contacts first.« less

Efficient Lead-Free Solar Cells Based on Hollow {en}MASnI3 Perovskites.

PubMed

Ke, Weijun; Stoumpos, Constantinos C; Spanopoulos, Ioannis; Mao, Lingling; Chen, Michelle; Wasielewski, Michael R; Kanatzidis, Mercouri G

2017-10-18

Tin-based perovskites have very comparable electronic properties to lead-based perovskites and are regarded as possible lower toxicity alternates for solar cell applications. However, the efficiency of tin-based perovskite solar cells is still low and they exhibit poor air stability. Here, we report lead-free tin-based solar cells with greatly enhanced performance and stability using so-called "hollow" ethylenediammonium and methylammonium tin iodide ({en}MASnI 3 ) perovskite as absorbers. Our results show that en can improve the film morphology and most importantly can serve as a new cation to be incorporated into the 3D MASnI 3 lattice. When the cation of en becomes part of the 3D structure, a high density of SnI 2 vacancies is created resulting in larger band gap, larger unit cell volume, lower trap-state density, and much longer carrier lifetime compared to classical MASnI 3 . The best-performing {en}MASnI 3 solar cell has achieved a high efficiency of 6.63% with an open circuit voltage of 428.67 mV, a short-circuit current density of 24.28 mA cm -2 , and a fill factor of 63.72%. Moreover, the {en}MASnI 3 device shows much better air stability than the neat MASnI 3 device. Comparable performance is also achieved for cesium tin iodide solar cells with en loading, demonstrating the broad scope of this approach.

Chronoamperometric study of the films formed by 4,4'-bipyridyl cation radical salts on mercury in the presence of iodide ions: consecutive two-dimensional phase transitions.

PubMed

Gómez, L; Ruiz, J J; Camacho, L; Rodríguez-Amaro, R

2005-01-04

This paper reports a new mathematical model for consecutive two-dimensional phase transitions that accounts for the chronoamperometric behavior observed in the formation of electrochemical phases by 4,4'-bipyridyl cation radical (BpyH(2)(*)(+)) on mercury in aqueous iodide solutions. Also, a new interpretation for the induction time is proposed.

Thermodynamic analysis of cesium and iodine behavior in severe light water reactor accidents

NASA Astrophysics Data System (ADS)

Minato, Kazuo

1991-11-01

In order to understand the release and transport behavior of cesium (Cs) and iodine (I) in severe light water reactor accidents, chemical forms of Cs and I in steam-hydrogen mixtures were analyzed thermodynamically. In the calculations reactions of boron (B) with Cs were taken into consideration. The analysis showed that B plays an important role in determining chemical forms of Cs. The main Cs-containing species are CsBO 2(g) and CsBO 2(l), depending on temperature. The contribution of CsOH(g) is minor. The main I-containing species are HI(g) and CsI(g) over the wide ranges of the parameters considered. Calculations were also carried out under the conditions of the Three Mile Island Unit 2 accident.

Wetting Transitions in ^4He/^3He Mixtures on Cesium

NASA Astrophysics Data System (ADS)

Ross, David

1997-03-01

Over the last several years, helium on cesium has proven to be an ideal model system for the study of wetting and wetting transitions(E. Cheng, M.W. Cole, W.F. Saam, and J. Treiner, Phys. Rev. Lett. 67), 1007 (1991).^,(J.E. Rutledge and P. Taborek, Phys. Rev. Lett. 69), 937 (1992).^,(D. Ross, J.E. Rutledge, and P. Taborek, Phys. Rev. Lett. 76), 2350 (1996).. This presentation will focus on the adsorption of binary liquid mixtures of the helium isotopes, ^3He and ^4He, on cesium substrates over a range of temperatures extending from 0.2 K to 1.0 K. The results, spanning ^3He concentrations from 0 to 1, constitute the first experimentally constructed complete wetting phase diagram for a two component liquid at a weakly binding substrate. The wetting behavior is particularly interesting in the vicinity of bulk liquid phase separation. A wetting transition of the ^4He rich liquid between the ^3He rich liquid and the cesium substrate has been found with Tw = 0.53 K. The surface phase transition line associated with this wetting transition is found to extend to both sides of the bulk phase separation line. On the ^3He rich side it is a prewetting line, and on the ^4He rich side it becomes a line of triple point induced dewetting transitions. General arguments indicate that this behavior should be typical of a large class of binary liquid mixtures at weakly binding substrates.

Behavior of radioactive cesium during incineration of radioactively contaminated wastes from decontamination activities in Fukushima.

PubMed

Fujiwara, Hiroshi; Kuramochi, Hidetoshi; Nomura, Kazutaka; Maeseto, Tomoharu; Osako, Masahiro

2017-11-01

Large volumes of decontamination wastes (DW) generated by off-site decontamination activities in Fukushima Prefecture have been incinerated since 2015. The behavior of radioactive cesium during incineration of DW was investigated at a working incineration plant. The incineration discharged bottom ash (BA) and fly ash (FA) with similar levels of radiocesium, and the leachability of the radiocesium from both types of ash was very low (<1%). These results are significantly different from those obtained for the incineration of contaminated municipal solid waste (CMSW) reported in earlier studies. The source of radiocesium in DW-FA is chiefly small particles derived from DW and DW-BA blown into the flue gas, not the deposition of gaseous synthesized radiocesium compounds on the surfaces of ash particles in the flue gas as observed in CMSW incineration. This source difference causes the behavior of radiocesium during waste incineration to differ between DW and CMSW. Copyright © 2017 Elsevier Ltd. All rights reserved.

Desorption of intrinsic cesium from smectite: inhibitive effects of clay particle organization on cesium desorption.

PubMed

Fukushi, Keisuke; Sakai, Haruka; Itono, Taeko; Tamura, Akihiro; Arai, Shoji

2014-09-16

Fine clay particles have functioned as transport media for radiocesium in terrestrial environments after nuclear accidents. Because radiocesium is expected to be retained in clay minerals by a cation-exchange reaction, ascertaining trace cesium desorption behavior in response to changing solution conditions is crucially important. This study systematically investigated the desorption behavior of intrinsic Cs (13 nmol/g) in well-characterized Na-montmorillonite in electrolyte solutions (NaCl, KCl, CaCl2, and MgCl2) under widely differing cation concentrations (0.2 mM to 0.2 M). Batch desorption experiments demonstrated that Cs(+) desorption was inhibited significantly in the presence of the environmental relevant concentrations of Ca(2+) and Mg(2+) (>0.5 mM) and high concentrations of K(+). The order of ability for Cs desorption was Na(+) = K(+) > Ca(2+) = Mg(2+) at the highest cation concentration (0.2 M), which is opposite to the theoretical prediction based on the cation-exchange selectivity. Laser diffraction grain-size analyses revealed that the inhibition of Cs(+) desorption coincided with the increase of the clay tactoid size. Results suggest that radiocesium in the dispersed fine clay particles adheres on the solid phase when the organization of swelling clay particles occurs because of changes in solution conditions caused by both natural processes and artificial treatments.

The Effect of Dopant-Free Hole-Transport Polymers on Charge Generation and Recombination in Cesium-Bismuth-Iodide Solar Cells.

PubMed

Zhu, Huimin; Johansson, Malin B; Johansson, Erik M J

2018-03-22

The photovoltaic characteristics of CsBi 3 I 10 -based solar cells with three dopant-free hole-conducting polymers are investigated. The effect on charge generation and charge recombination in the solar cells using the different polymers is studied and the results indicate that the choice of polymer strongly affects the device properties. Interestingly, for the solar cell with poly[[2,3-bis(3-octyloxyphenyl)-5,8-quinoxalinediyl]-2,5-thiophenediyl] (TQ1), the photon-to-current conversion spectrum is highly improved in the red wavelength region, suggesting that the polymer also contributes to the photocurrent generation in this case. This report provides a new direction for further optimization of Bi-halide solar cells by using dopant-free hole-transporting polymers and shows that the energy levels and the interaction between the Bi-halide and the conducting polymers are very important for solar cell performance. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Degradation of Highly Alloyed Metal Halide Perovskite Precursor Inks: Mechanism and Storage Solutions

DOE PAGES

Dou, Benjia; Wheeler, Lance M.; Christians, Jeffrey A.; ...

2018-03-14

Whereas the promise of metal halide perovskite (MHP) photovoltaics (PV) is that they can combine high efficiency with solution-processability, the chemistry occurring in precursor inks is largely unexplored. Herein, we investigate the degradation of MHP solutions based on the most widely used solvents, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). For the MHP inks studied, which contain formamidinium (FA+), methylammonium (MA+), cesium (Cs+), lead (Pb2+), bromide (Br-), and iodide (I-), dramatic compositional changes are observed following storage of the inks in nitrogen in the dark. We show that hydrolysis of DMF in the precursor solution forms dimethylammonium formate, which subsequently incorporatesmore » into the MHP film to compromise the ability of Cs+ and MA+ to stabilize FA+-based MHP. The changes in solution chemistry lead to a modification of the perovskite film stoichiometry, band gap, and structure. The solid precursor salts are stable when ball-milled into a powder, allowing for the storage of large quantities of stoichiometric precursor materials.« less

ICP-MS measurement of iodine diffusion in IG-110 graphite for HTGR/VHTR

NASA Astrophysics Data System (ADS)

Carter, L. M.; Brockman, J. D.; Robertson, J. D.; Loyalka, S. K.

2016-05-01

Graphite functions as a structural material and as a barrier to fission product release in HTGR/VHTR designs, and elucidation of transport parameters for fission products in reactor-grade graphite is thus required for reactor source terms calculations. We measured iodine diffusion in spheres of IG-110 graphite using a release method based on Fickain diffusion kinetics. Two sources of iodine were loaded into the graphite spheres; molecular iodine (I2) and cesium iodide (CsI). Measurements of the diffusion coefficient were made over a temperature range of 873-1293 K. We have obtained the following Arrhenius expressions for iodine diffusion:DI , CsI infused =(6 ×10-12 2/s) exp(30,000 J/mol RT) And,DI , I2 infused =(4 ×10-10 m2/s) exp(-11,000 J/mol RT ) The results indicate that iodine diffusion in IG-110 graphite is not well-described by Fickan diffusion kinetics. To our knowledge, these are the first measurements of iodine diffusion in IG-110 graphite.

Characterization of on-site digital mammography systems: Direct versus indirect conversion detectors

NASA Astrophysics Data System (ADS)

Youn, Hanbean; Han, Jong Chul; Yun, Seungman; Kam, Soohwa; Cho, Seungryong; Kim, Ho Kyung

2015-06-01

We investigated the performances of two digital mammography systems. The systems use a cesium-iodide (CsI) scintillator and an amorphous selenium ( a-Se) photoconductor for X-ray detection and are installed in the same hospital. As physical metrics, we measured the modulationtransfer function (MTF), the noise-power spectrum (NPS), and the detective quantum efficiency (DQE). In addition, we analyzed the contrast-detail performances of the two systems by using a commercial contrast-detail phantom. The CsI-based indirect conversion detector provided better MTF and DQE performances than the a-Se-based direct conversion detector whereas the former provided a poorer NPS performance than the latter. These results are explained by the fact that the CsI-based detector used an MTF restoration preprocessing algorithm. The a-Se-based detector showed better contrast-detail performance than the CsI-based detector. We believe that the highfrequency noise characteristic of a detector is more responsible for the visibility of small details than its spatial-resolution performance.

Characterization of ParTI Phoswiches Using Charged Pion Beams

NASA Astrophysics Data System (ADS)

Churchman, Emily; Zarrella, Andrew; Youngs, Michael; Yennello, Sherry

2017-09-01

The Partial Truncated Icosahedron (ParTI) detector array consists of 15 phoswiches. Each phoswich is made of two scintillating components - a thallium-doped cesium iodide (CsI(Tl)) crystal and an EJ-212 scintillating plastic - coupled to a photomultiplier tube. Both materials have different scintillation times and are sensitive to both charged and neutral particles. The type of particle and amount of energy deposited determine the shape of the scintillation pulse as a function of time. By integrating the fast and slow signals of the scintillation pulses, a ``Fast vs. Slow Integration'' plot can be created that produces particle identification lines based on the energy deposited in the scintillating materials. Four of these phoswiches were taken to the Paul Scherrer Institute (PSI) in Switzerland where π + , π-, and proton beams were scattered onto the phoswiches to demonstrate their particle identification (PID) capabilities. Using digitizers to record the detector response waveforms, pions can also be identified by the characteristic decay pulse of the muon daughters.

Degradation of Highly Alloyed Metal Halide Perovskite Precursor Inks: Mechanism and Storage Solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dou, Benjia; Wheeler, Lance M.; Christians, Jeffrey A.

Whereas the promise of metal halide perovskite (MHP) photovoltaics (PV) is that they can combine high efficiency with solution-processability, the chemistry occurring in precursor inks is largely unexplored. Herein, we investigate the degradation of MHP solutions based on the most widely used solvents, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). For the MHP inks studied, which contain formamidinium (FA+), methylammonium (MA+), cesium (Cs+), lead (Pb2+), bromide (Br-), and iodide (I-), dramatic compositional changes are observed following storage of the inks in nitrogen in the dark. We show that hydrolysis of DMF in the precursor solution forms dimethylammonium formate, which subsequently incorporatesmore » into the MHP film to compromise the ability of Cs+ and MA+ to stabilize FA+-based MHP. The changes in solution chemistry lead to a modification of the perovskite film stoichiometry, band gap, and structure. The solid precursor salts are stable when ball-milled into a powder, allowing for the storage of large quantities of stoichiometric precursor materials.« less

Composition and process for separating cesium ions from an acidic aqueous solution also containing other ions

DOEpatents

Dietz, Mark L.; Horwitz, E. Philip; Bartsch, Richard A.; Barrans, Jr., Richard E.; Rausch, David

1999-01-01

A crown ether cesium ion extractant is disclosed as is its synthesis. The crown ether cesium ion extractant is useful for the selective purification of cesium ions from aqueous acidic media, and more particularly useful for the isolation of radioactive cesium-137 from nuclear waste streams. Processes for isolating cesium ions from aqueous acidic media using the crown ether cesium extractant are disclosed as are processes for recycling the crown ether cesium extractant and processes for recovering cesium from a crown ether cesium extractant solution.

Composition and process for separating cesium ions from an acidic aqueous solution also containing other ions

DOEpatents

Dietz, M.L.; Horwitz, E.P.; Bartsch, R.A.; Barrans, R.E. Jr.; Rausch, D.

1999-03-30

A crown ether cesium ion extractant is disclosed as is its synthesis. The crown ether cesium ion extractant is useful for the selective purification of cesium ions from aqueous acidic media, and more particularly useful for the isolation of radioactive cesium-137 from nuclear waste streams. Processes for isolating cesium ions from aqueous acidic media using the crown ether cesium extractant are disclosed as are processes for recycling the crown ether cesium extractant and processes for recovering cesium from a crown ether cesium extractant solution. 4 figs.

Direct detection of sub-GeV dark matter with scintillating targets

DOE PAGES

Derenzo, Stephen; Essig, Rouven; Massari, Andrea; ...

2017-07-28

We suggest a novel experimental concept for detecting MeV-to-GeV-mass dark matter, in which the dark matter scatters off electrons in a scintillating target and produces a signal of one or a few photons. New large-area photodetectors are needed to measure the photon signal with negligible dark counts, which could be constructed from transition edge sensor (TES) or microwave kinetic inductance detector (MKID) technology. Alternatively, detecting two photons in coincidence may allow the use of conventional photodetectors like photomultiplier tubes. Here we describe why scintillators may have distinct advantages over other experiments searching for a low ionization signal from sub-GeV darkmore » matter, as there are fewer potential sources of spurious backgrounds. We discuss various target choices, but focus on calculating the expected dark matter-electron scattering rates in three scintillating crystals: sodium iodide (NaI), cesium iodide (CsI), and gallium arsenide (GaAs). Among these, GaAs has the lowest band gap (1.52 eV) compared to NaI (5.9 eV) or CsI (6.4 eV), which in principle allows it to probe dark matter masses as low as ~0.5 MeV, compared to ~1.5 MeV with NaI or CsI. We compare these scattering rates with those expected in silicon (Si) and germanium (Ge). The proposed experimental concept presents an important complementary path to existing efforts, and its potential advantages may make it the most sensitive direct-detection probe of dark matter down to MeV masses.« less

Direct detection of sub-GeV dark matter with scintillating targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Derenzo, Stephen; Essig, Rouven; Massari, Andrea

We suggest a novel experimental concept for detecting MeV-to-GeV-mass dark matter, in which the dark matter scatters off electrons in a scintillating target and produces a signal of one or a few photons. New large-area photodetectors are needed to measure the photon signal with negligible dark counts, which could be constructed from transition edge sensor (TES) or microwave kinetic inductance detector (MKID) technology. Alternatively, detecting two photons in coincidence may allow the use of conventional photodetectors like photomultiplier tubes. Here we describe why scintillators may have distinct advantages over other experiments searching for a low ionization signal from sub-GeV darkmore » matter, as there are fewer potential sources of spurious backgrounds. We discuss various target choices, but focus on calculating the expected dark matter-electron scattering rates in three scintillating crystals: sodium iodide (NaI), cesium iodide (CsI), and gallium arsenide (GaAs). Among these, GaAs has the lowest band gap (1.52 eV) compared to NaI (5.9 eV) or CsI (6.4 eV), which in principle allows it to probe dark matter masses as low as ~0.5 MeV, compared to ~1.5 MeV with NaI or CsI. We compare these scattering rates with those expected in silicon (Si) and germanium (Ge). The proposed experimental concept presents an important complementary path to existing efforts, and its potential advantages may make it the most sensitive direct-detection probe of dark matter down to MeV masses.« less

Synthetic Studies of Antimony Sulfur Iodide and Predictions/Synthesis of New Nitrogen Containing Crystal Structures.

DTIC Science & Technology

1983-02-01

Okazaki, 2 it appeared likely that well-aligned SbSI would have extremely useful piezoelectric properties. It was appreciated that a source of high purity...which often facilitate this, and may also lead to special physical effects (as with the ferroelectric behavior of SbSI). In hydroxyapatite , there are two...Fabrication of Piezoelectric Cerdmics," Ferroelectrics 41, 77-69 (1982). 3. P.E.O. Morgan, "Synthetic Studies of Antimony Sulfur Iodide," Proposal to ONR from

MODELING OF ION-EXCHANGE FOR CESIUM REMOVAL FROM DISSOLVED SALTCAKE IN SRS TANKS 1-3, 37 AND 41

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, F

2007-08-15

This report presents an evaluation of the expected performance of engineered Crystalline Silicotitanate (CST) and spherical Resorcinol-Formaldehyde (RF) ion exchange resin for the removal of cesium from dissolved saltcake in SRS Tanks 1-3, 37 and 41. The application presented in this report reflects the expected behavior of engineered CST IE-911 and spherical RF resin manufactured at the intermediate-scale (approximately 100 gallon batch size; batch 5E-370/641). It is generally believed that scale-up to production-scale in RF resin manufacturing will result in similarly behaving resin batches whose chemical selectivity is unaffected while total capacity per gram of resin may vary. As such,more » the predictions provided within this report should provide reasonable estimates of production-scale column performance. Two versions of the RF cesium isotherm were used. The older version provides a conservative estimate of the resin capacity while the newer version more accurately fits the most recent experimental data.« less

Atmospheric behavior, deposition, and budget of radioactive materials from the Fukushima Daiichi nuclear power plant in March 2011

NASA Astrophysics Data System (ADS)

Morino, Y.; Ohara, T.; Nishizawa, M.

2011-12-01

To understand the atmospheric behavior of radioactive materials emitted from the Fukushima Daiichi nuclear power plant after the nuclear accident that accompanied the great Tohoku earthquake and tsunami on 11 March 2011, we simulated the transport and deposition of iodine-131 and cesium-137 using a chemical transport model. The model roughly reproduced the observed temporal and spatial variations of deposition rates over 15 Japanese prefectures (60-400 km from the plant), including Tokyo, although there were some discrepancies between the simulated and observed rates. These discrepancies were likely due to uncertainties in the simulation of emission, transport, and deposition processes in the model. A budget analysis indicated that approximately 13% of iodine-131 and 22% of cesium-137 were deposited over land in Japan, and the rest was deposited over the ocean or transported out of the model domain (700 × 700 km2). Radioactivity budgets are sensitive to temporal emission patterns. Accurate estimation of emissions to the air is important for estimation of the atmospheric behavior of radionuclides and their subsequent behavior in land water, soil, vegetation, and the ocean.

Atmospheric behavior, deposition, and budget of radioactive materials from the Fukushima Daiichi nuclear power plant in March 2011

NASA Astrophysics Data System (ADS)

Morino, Yu; Ohara, Toshimasa; Nishizawa, Masato

2011-09-01

To understand the atmospheric behavior of radioactive materials emitted from the Fukushima Daiichi nuclear power plant after the nuclear accident that accompanied the great Tohoku earthquake and tsunami on 11 March 2011, we simulated the transport and deposition of iodine-131 and cesium-137 using a chemical transport model. The model roughly reproduced the observed temporal and spatial variations of deposition rates over 15 Japanese prefectures (60-400 km from the plant), including Tokyo, although there were some discrepancies between the simulated and observed rates. These discrepancies were likely due to uncertainties in the simulation of emission, transport, and deposition processes in the model. A budget analysis indicated that approximately 13% of iodine-131 and 22% of cesium-137 were deposited over land in Japan, and the rest was deposited over the ocean or transported out of the model domain (700 × 700 km2). Radioactivity budgets are sensitive to temporal emission patterns. Accurate estimation of emissions to the air is important for estimation of the atmospheric behavior of radionuclides and their subsequent behavior in land water, soil, vegetation, and the ocean.

Facile hydrothermal synthesis and characterization of cesium-doped PbI2 nanostructures for optoelectronic, radiation detection and photocatalytic applications

NASA Astrophysics Data System (ADS)

Shkir, Mohd; AlFaify, S.; Yahia, I. S.; Hamdy, Mohamed S.; Ganesh, V.; Algarni, H.

2017-10-01

Low-temperature hydrothermal-assisted synthesis of pure and cesium (Cs) (1, 3, 5, 7 and 10 wt%) doped lead iodide (PbI2) nanorods and nanosheets have been achieved successfully for the first time. The structural and vibrational studies confirm the formation of a 2H-polytypic PbI2 predominantly. Scanning electron microscope analysis confirms the formation of well-aligned nanorods of average size 100 nm at low concentration and nanosheets of average thicknesses in the range of 20-40 nm at higher concentrations of Cs doping. The presence of Cs doping was confirmed by energy dispersive X-ray study. Ultra-violet-visible absorbance spectra were recorded, and energy gap was calculated in the range of 3.33 to 3.45 eV for pure and Cs-doped PbI2 nanostructures which is higher than the bulk value (i.e., 2.27 eV) due to quantum confinement effect. Dielectric constant, loss, and AC conductivity studies have been done. Enhancement in Gamma linear absorption coefficient due to Cs doping confirms the suitability of prepared nanostructures for radiation detection applications. Furthermore, the photocatalytic performance of the synthesized nanostructures was evaluated in the decolorization of methyl green (MG) and methyl orange (MO) under the illumination of visible light (λ > 420 nm). The observed photocatalytic activity for 5 and 7 wt% Cs-doped PbI2 was observed to be more than pure PbI2 and also > 10 times higher than the commercially available photocatalysts. The results suggest that the prepared nanostructures are highly applicable in optoelectronic, radiation detection and many other applications. [Figure not available: see fulltext.

Stress corrosion cracking of Zircaloys in unirradiated and irradiated CsI

NASA Astrophysics Data System (ADS)

Cox, B.; Surette, B. A.; Wood, J. C.

1986-03-01

Unirradiated split-ring specimens of Zircaloy fuel cladding, coated with CsI, cracked when stressed at elevated temperatures. The specimens have been reexamined fractographically and metallographically in order to confirm that the cause of cracking was stress corrosion (SCC) and not delayed hydride cracking (DHC). Further specimens have been cracked at 350°C by a solution of CsI in a fused mixture of nitrates of rubidium, cesium, strontium and barium, by a similar mechanism. CsI dissolved in a fused molybdate melt was not stable at 400°C, and rapidly evolved iodine, leaving a melt that was incapable of causing SCC. Irradiation of stressed split-ring specimens of Zircaloy fuel cladding in a γ-irradiator of 10 6 R/h and in the U-5 loop in the NRU reactor at an estimated 10 9 R/h caused SCC when the specimens were packed in dry CsI powder. Care had to be taken to dry the CsI, otherwise cracking occurred by a DHC mechanism from hydrogen absorbed from residual moisture in the CsI. Fractography showed that the crack surfaces obtained with dry CsI were typical of iodine-induced SCC rather than cesium-induced metal vapour embrittlement. Thus, if a transport process is provided for the iodide to obtain access to the zirconium surface, CsI is capable of causing SCC of Zircaloy. This transport process might be ionic diffusion in a fission product oxide melt in the fuel-clad gap, however, radiolysis of CsI to form a volatile iodine species in a radiation field is the more probable explanation of PCI failures.

Sorption and transport of iodine species in sediments from the Savannah River and Hanford Sites.

PubMed

Hu, Qinhong; Zhao, Pihong; Moran, Jean E; Seaman, John C

2005-07-01

Iodine is an important element in studies of environmental protection and human health, global-scale hydrologic processes and nuclear nonproliferation. Biogeochemical cycling of iodine is complex, because iodine occurs in multiple oxidation states and as inorganic and organic species that may be hydrophilic, atmophilic, and biophilic. In this study, we applied new analytical techniques to study the sorption and transport behavior of iodine species (iodide, iodate, and 4-iodoaniline) in sediments collected at the Savannah River and Hanford Sites, where anthropogenic (129)I from prior nuclear fuel processing activities poses an environmental risk. We conducted integrated column and batch experiments to investigate the interconversion, sorption and transport of iodine species, and the sediments we examined exhibit a wide range in organic matter, clay mineralogy, soil pH, and texture. The results of our experiments illustrate complex behavior with various processes occurring, including iodate reduction, irreversible retention or mass loss of iodide, and rate-limited and nonlinear sorption. There was an appreciable iodate reduction to iodide, presumably mediated by the structural Fe(II) in some clay minerals; therefore, careful attention must be given to potential interconversion among species when interpreting the biogeochemical behavior of iodine in the environment. The different iodine species exhibited dramatically different sorption and transport behavior in three sediment samples, possessing different physico-chemical properties, collected from different depths at the Savannah River Site. Our study yielded additional insight into processes and mechanisms affecting the geochemical cycling of iodine in the environment, and provided quantitative estimates of key parameters (e.g., extent and rate of sorption) for risk assessment at these sites.

Band Gap Tuning via Lattice Contraction and Octahedral Tilting in Perovskite Materials for Photovoltaics

DOE PAGES

Prasanna, Rohit; Gold-Parker, Aryeh; Leijtens, Tomas; ...

2017-07-13

Tin and lead iodide perovskite semiconductors of the composition AMX 3, where M is a metal and X is a halide, are leading candidates for high efficiency low cost tandem photovoltaics, in part because they have band gaps that can be tuned over a wide range by compositional substitution. We experimentally identify two competing mechanisms through which the A-site cation influences the band gap of 3D metal halide perovskites. Using a smaller A-site cation can distort the perovskite lattice in two distinct ways: by tilting the MX 6 octahedra or by simply contracting the lattice isotropically. The former effect tendsmore » to raise the band gap, while the latter tends to decrease it. Lead iodide perovskites show an increase in band gap upon partial substitution of the larger formamidinium with the smaller cesium, due to octahedral tilting. Perovskites based on tin, which is slightly smaller than lead, show the opposite trend: they show no octahedral tilting upon Cs-substitution but only a contraction of the lattice, leading to progressive reduction of the band gap. We outline a strategy to systematically tune the band gap and valence and conduction band positions of metal halide perovskites through control of the cation composition. Using this strategy, we demonstrate solar cells that harvest light in the infrared up to 1040 nm, reaching a stabilized power conversion efficiency of 17.8%, showing promise for improvements of the bottom cell of all-perovskite tandem solar cells. In conclusion, the mechanisms of cation-based band gap tuning we describe are broadly applicable to 3D metal halide perovskites and will be useful in further development of perovskite semiconductors for optoelectronic applications.« less

Band Gap Tuning via Lattice Contraction and Octahedral Tilting in Perovskite Materials for Photovoltaics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prasanna, Rohit; Gold-Parker, Aryeh; Leijtens, Tomas

Tin and lead iodide perovskite semiconductors of the composition AMX 3, where M is a metal and X is a halide, are leading candidates for high efficiency low cost tandem photovoltaics, in part because they have band gaps that can be tuned over a wide range by compositional substitution. We experimentally identify two competing mechanisms through which the A-site cation influences the band gap of 3D metal halide perovskites. Using a smaller A-site cation can distort the perovskite lattice in two distinct ways: by tilting the MX 6 octahedra or by simply contracting the lattice isotropically. The former effect tendsmore » to raise the band gap, while the latter tends to decrease it. Lead iodide perovskites show an increase in band gap upon partial substitution of the larger formamidinium with the smaller cesium, due to octahedral tilting. Perovskites based on tin, which is slightly smaller than lead, show the opposite trend: they show no octahedral tilting upon Cs-substitution but only a contraction of the lattice, leading to progressive reduction of the band gap. We outline a strategy to systematically tune the band gap and valence and conduction band positions of metal halide perovskites through control of the cation composition. Using this strategy, we demonstrate solar cells that harvest light in the infrared up to 1040 nm, reaching a stabilized power conversion efficiency of 17.8%, showing promise for improvements of the bottom cell of all-perovskite tandem solar cells. In conclusion, the mechanisms of cation-based band gap tuning we describe are broadly applicable to 3D metal halide perovskites and will be useful in further development of perovskite semiconductors for optoelectronic applications.« less

Band Gap Tuning via Lattice Contraction and Octahedral Tilting in Perovskite Materials for Photovoltaics.

PubMed

Prasanna, Rohit; Gold-Parker, Aryeh; Leijtens, Tomas; Conings, Bert; Babayigit, Aslihan; Boyen, Hans-Gerd; Toney, Michael F; McGehee, Michael D

2017-08-16

Tin and lead iodide perovskite semiconductors of the composition AMX 3 , where M is a metal and X is a halide, are leading candidates for high efficiency low cost tandem photovoltaics, in part because they have band gaps that can be tuned over a wide range by compositional substitution. We experimentally identify two competing mechanisms through which the A-site cation influences the band gap of 3D metal halide perovskites. Using a smaller A-site cation can distort the perovskite lattice in two distinct ways: by tilting the MX 6 octahedra or by simply contracting the lattice isotropically. The former effect tends to raise the band gap, while the latter tends to decrease it. Lead iodide perovskites show an increase in band gap upon partial substitution of the larger formamidinium with the smaller cesium, due to octahedral tilting. Perovskites based on tin, which is slightly smaller than lead, show the opposite trend: they show no octahedral tilting upon Cs-substitution but only a contraction of the lattice, leading to progressive reduction of the band gap. We outline a strategy to systematically tune the band gap and valence and conduction band positions of metal halide perovskites through control of the cation composition. Using this strategy, we demonstrate solar cells that harvest light in the infrared up to 1040 nm, reaching a stabilized power conversion efficiency of 17.8%, showing promise for improvements of the bottom cell of all-perovskite tandem solar cells. The mechanisms of cation-based band gap tuning we describe are broadly applicable to 3D metal halide perovskites and will be useful in further development of perovskite semiconductors for optoelectronic applications.

Investigation of the unusual behavior of cesium-137 and other radionuclides in the Florida environment. Progress report, September 1, 1975--August 31, 1976. [Digitaria decumbens, Paspalum notatum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gamble, J.F.

1976-01-01

The most significant development in the contract year was the documentation of the presence of endomycorrhizal, vesicular arbuscular (V-A) mycorrhizae in the pasture systems of south Florida that have the elevated levels of cesium-137 activity. In all samples the V-A hyphal network was well developed and growing throughout the particles of organic matter. The organic particles are held in a loose, aggregate structure by the hyphal network. In improved pastures of Digitaria decumbens (pangola) and Paspalum notatum (bahiagrass) the root infection ranged from 24 to 95 percent. The principle association was Gigaspora and Glomus sp. In the unimproved pastures ofmore » mostly Aristida stricta (wiregrass) and Serenoa repens (saw palmetto) the infection was 70 percent and only Acaulospora laevis was found. Experiments are in progress to show whether there are differences in cesium uptake between mycorrhizal and non-mycorrhizal grass plants. The test grass is pangola. Greenhouse tests involve V-A mycorrhizal control using a fungicide, the infection of grass cuttings with mycorrhizal strains found in the test area. These pot experiments will serve as pilot programs for field experiments. The effects of ectomycorrhizal associations on uptake of cesium in pine seedlings is also being studied. Analysis of the dynamics of organic matter cycling in a mesic hardwood forest shows that the rates of organic matter flow are similar to tropical systems although the plant species are warm temperate. The increased tempo of organic turnover probably contributes to the observed higher-than-expected levels of cesium-137 activity in Florida biosystems.« less

METHOD OF PREPARING RADIOACTIVE CESIUM SOURCES

DOEpatents

Quinby, T.C.

1963-12-17

A method of preparing a cesium-containing radiation source with physical and chemical properties suitable for high-level use is presented. Finely divided silica is suspended in a solution containing cesium, normally the fission-product isotope cesium 137. Sodium tetraphenyl boron is then added to quantitatively precipitate the cesium. The cesium-containing precipitate is converted to borosilicate glass by heating to the melting point and cooling. Up to 60 weight percent cesium, with a resulting source activity of up to 21 curies per gram, is incorporated in the glass. (AEC)

Nucleation and growth of thin films of the organic conductor TTF-iodide over glassy carbon. Electrochemical and spectroelectrochemical study.

PubMed

Gómez, L; Rodríguez-Amaro, R

2009-04-21

On the basis of the electrochemical and spectroelectrochemical behavior of thin films of TTF over a glassy carbon electrode in iodide media, a new, more complete mechanism for the electrode processes involved is proposed. The voltammetric and chronoamperometric results for the films can be explained in light of a recently developed nucleation-growth model involving a layer-by-layer mechanism. Also, their in situ UV-vis spectral data expand the available knowledge about the overall mechanism and the nature of the compound formed over the glassy carbon electrode.

Surface and Bulk Characteristics of Cesium Iodide (CsI) coated Carbon (C) Fibers for High Power Microwave (HPM) Field Emission Cathodes

NASA Astrophysics Data System (ADS)

Vlahos, Vasilios; Morgan, Dane; Booske, John H.; Shiffler, Don

2008-11-01

CsI coated C fibers [1] are promising field emission cathodes for HPM applications. Ab initio computational modeling has shown that atomically-thin CsI coatings reduce the work function of C substrates by a surface dipole mechanism [2]. Characterization measurements of the composition and morphology of the CsI-coated C fibers are underway for determining the properties and characteristics of the following important regions of the fiber: (i) the surface on the tip of the fiber where the majority of electron emission is believed to occur, (ii) the surface covering the body of the fiber and its role on the emission properties of the system, and (iii) the interior volume of the fiber and its effects on the CsI surface re-supply process and rate. The results will be interpreted in terms of surface electronic properties and theoretical electron emission models. [1]D. Shiffler, et al., Phys. Plasmas 11 (2004) 1680. [2]V.Vlahos et al., Appl. Phys. Lett. 91 (2007) 144102.

Characterization of an ultraviolet imaging detector with high event rate ROIC (HEROIC) readout

NASA Astrophysics Data System (ADS)

Nell, Nicholas; France, Kevin; Harwit, Alex; Bradley, Scott; Franka, Steve; Freymiller, Ed; Ebbets, Dennis

2016-07-01

We present characterization results from a photon counting imaging detector consisting of one microchannel plate (MCP) and an array of two readout integrated circuits (ROIC) that record photon position. The ROICs used in the position readout are the high event rate ROIC (HEROIC) devices designed to handle event rates up to 1 MHz per pixel, recently developed by the Ball Aerospace and Technologies Corporation in collaboration with the University of Colorado. An opaque cesium iodide (CsI) photocathode sensitive in the far-ultraviolet (FUV; 122-200 nm), is deposited on the upper surface of the MCP. The detector is characterized in a chamber developed by CU Boulder that is capable of illumination with vacuum-ultraviolet (VUV) monochromatic light and measurement of absolute ux with a calibrated photodiode. Testing includes investigation of the effects of adjustment of internal settings of the HEROIC devices including charge threshold, gain, and amplifier bias. The detector response to high count rates is tested. We report initial results including background, uniformity, and quantum detection efficiency (QDE) as a function of wavelength.

A balloon measurement of the isotopic composition of galactic cosmic ray boron, carbon and nitrogen. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Zumberge, J. F.

1981-01-01

The isotopic compositions of galactic cosmic ray boron, carbon, and nitrogen were measured at energies near 300 MeV amu, using a balloon-borne instrument at an atmospheric depth of approximately 5 g/sq cm. The calibrations of the detectors comprising the instrument are described. The saturation properties of the cesium iodide scintillators used for measurement of particle energy are studied in the context of analyzing the data for mass. The achieved rms mass resolution varies from approximately 0.3 amu at boron to approximately 0.5 amu at nitrogen, consistent with a theoretical analysis of the contributing factors. Corrected for detector interactions and the effects of the residual atmosphere the results are B-10/B=0.33 (+0.17, -0.11), C-13/C=0.06 (+0.13, -0.11), and N-15/N=0.42 (+0.19, -0.17). A model of galactic propagation and solar modulation is described. Assuming a cosmic ray source composition of solar-like isotopic abundances, the model predicts abundances near Earth consistent with the measurements.

Photon Reabsorption in Mixed CsPbCl3:CsPbI3 Perovskite Nanocrystal Films for Light-Emitting Diodes

PubMed Central

2017-01-01

Cesium lead halide nanocrystals, CsPbX3 (X = Cl, Br, I), exhibit photoluminescence quantum efficiencies approaching 100% without the core–shell structures usually used in conventional semiconductor nanocrystals. These high photoluminescence efficiencies make these crystals ideal candidates for light-emitting diodes (LEDs). However, because of the large surface area to volume ratio, halogen exchange between perovskite nanocrystals of different compositions occurs rapidly, which is one of the limiting factors for white-light applications requiring a mixture of different crystal compositions to achieve a broad emission spectrum. Here, we use mixtures of chloride and iodide CsPbX3 (X = Cl, I) perovskite nanocrystals where anion exchange is significantly reduced. We investigate samples containing mixtures of perovskite nanocrystals with different compositions and study the resulting optical and electrical interactions. We report excitation transfer from CsPbCl3 to CsPbI3 in solution and within a poly(methyl methacrylate) matrix via photon reabsorption, which also occurs in electrically excited crystals in bulk heterojunction LEDs. PMID:28316756

Validation of columnar CsI x-ray detector responses obtained with hybridMANTIS, a CPU-GPU Monte Carlo code for coupled x-ray, electron, and optical transport.

PubMed

Sharma, Diksha; Badano, Aldo

2013-03-01

hybridMANTIS is a Monte Carlo package for modeling indirect x-ray imagers using columnar geometry based on a hybrid concept that maximizes the utilization of available CPU and graphics processing unit processors in a workstation. The authors compare hybridMANTIS x-ray response simulations to previously published MANTIS and experimental data for four cesium iodide scintillator screens. These screens have a variety of reflective and absorptive surfaces with different thicknesses. The authors analyze hybridMANTIS results in terms of modulation transfer function and calculate the root mean square difference and Swank factors from simulated and experimental results. The comparison suggests that hybridMANTIS better matches the experimental data as compared to MANTIS, especially at high spatial frequencies and for the thicker screens. hybridMANTIS simulations are much faster than MANTIS with speed-ups up to 5260. hybridMANTIS is a useful tool for improved description and optimization of image acquisition stages in medical imaging systems and for modeling the forward problem in iterative reconstruction algorithms.

Mineral resource of the month: cesium

USGS Publications Warehouse

Angulo, Marc A.

2010-01-01

The article offers information on cesium, a golden alkali metal derived from the Latin word caesium which means bluish gray. It mentions that cesium is the first element discovered with the use of spectroscopy. It adds that the leading producer and supplier of cesium is Canada and there are 50,000 kilograms of cesium consumed of the world in a year. Moreover, it states that only 85% of the cesium formate can be retrieved and recycled.

Development of a Chemical Process for Production of Cesium Chloride from a Canadian Pollucite Ore

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parsons, H. W.; Vezina, J. A.; Simard, R.

1963-01-01

A chemical process was developed for the production of a high-purity cesium chioride from a pollucite (cesium aluminum silicate) ore from the Manitoba deposit of Chemalloy Minerais Ltd. The history of the deposit, and the present and possible future uses of cesium are briefly reviewed. Laboratory and piiot plant investigations on this ore have shown that a cyclic sulphuric acid leach followed by fractional crystallization will produce a rubidiumfree cesium alum, which can be converted to cesium chloride by thermal decomposition and ion exchange. On the basis of these findings it is concluded that the process is applicable to themore » tonnage production of cesium chloride. Reagent consumption was found to be 3.3 sulphuric acid and 0.3 lb hydrochloric acid per pound of cesium extracted. Overall extraction of cesium was 95 to 96%. (auth)« less

A novel role for methyl cysteinate, a cysteine derivative, in cesium accumulation in Arabidopsis thaliana

PubMed Central

Adams, Eri; Miyazaki, Takae; Hayaishi-Satoh, Aya; Han, Minwoo; Kusano, Miyako; Khandelia, Himanshu; Saito, Kazuki; Shin, Ryoung

2017-01-01

Phytoaccumulation is a technique to extract metals from soil utilising ability of plants. Cesium is a valuable metal while radioactive isotopes of cesium can be hazardous. In order to establish a more efficient phytoaccumulation system, small molecules which promote plants to accumulate cesium were investigated. Through chemical library screening, 14 chemicals were isolated as ‘cesium accumulators’ in Arabidopsis thaliana. Of those, methyl cysteinate, a derivative of cysteine, was found to function within the plant to accumulate externally supplemented cesium. Moreover, metabolite profiling demonstrated that cesium treatment increased cysteine levels in Arabidopsis. The cesium accumulation effect was not observed for other cysteine derivatives or amino acids on the cysteine metabolic pathway tested. Our results suggest that methyl cysteinate, potentially metabolised from cysteine, binds with cesium on the surface of the roots or inside plant cells and improve phytoaccumulation. PMID:28230101

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

PubMed

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

2017-06-01

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

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

NASA Astrophysics Data System (ADS)

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

2017-06-01

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

Modeling of boron species in the Falcon 17 and ISP-34 integral tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lazaridis, M.; Capitao, J.A.; Drossinos, Y.

1996-09-01

The RAFT computer code for aerosol formation and transport was modified to include boron species in its chemical database. The modification was necessary to calculate fission product transport and deposition in the FAL-17 and ISP-34 Falcon tests, where boric acid was injected. The experimental results suggest that the transport of cesium is modified in the presence of boron. The results obtained with the modified RAFT code are presented; they show good agreement with experimental results for cesium and partial agreement for boron deposition in the Falcon silica tube. The new version of the RAFT code predicts the same behavior formore » iodine deposition as the previous version, where boron species were not included.« less

Wide Area Recovery and Resiliency Program (WARRP) Integrated Program Plan

DTIC Science & Technology

2011-06-01

Agent YELLOW, which is a mixture of the chemical warfare agents Sulfur Mustard and Lewisite, is a liquid with a garlic-like odor. Sulfur mustard...Radioisotope Background Cesium -137 (137Cs) is a radioactive isotope of cesium . The half-life of cesium -137 is 30.17 years. Because of the chemical...nature of cesium , it moves easily through the environment. This makes the cleanup of cesium - 137 difficult. People may ingest cesium -137 with food

Anharmonicity and Disorder in the Black Phases of Cesium Lead Iodide Used for Stable Inorganic Perovskite Solar Cells.

PubMed

Marronnier, Arthur; Roma, Guido; Boyer-Richard, Soline; Pedesseau, Laurent; Jancu, Jean-Marc; Bonnassieux, Yvan; Katan, Claudine; Stoumpos, Constantinos C; Kanatzidis, Mercouri G; Even, Jacky

2018-04-24

Hybrid organic-inorganic perovskites emerged as a new generation of absorber materials for high-efficiency low-cost solar cells in 2009. Very recently, fully inorganic perovskite quantum dots also led to promising efficiencies, making them a potentially stable and efficient alternative to their hybrid cousins. Currently, the record efficiency is obtained with CsPbI 3 , whose crystallographical characterization is still limited. Here, we show through high-resolution in situ synchrotron XRD measurements that CsPbI 3 can be undercooled below its transition temperature and temporarily maintained in its perovskite structure down to room temperature, stabilizing a metastable perovskite polytype (black γ-phase) crucial for photovoltaic applications. Our analysis of the structural phase transitions reveals a highly anisotropic evolution of the individual lattice parameters versus temperature. Structural, vibrational, and electronic properties of all the experimentally observed black phases are further inspected based on several theoretical approaches. Whereas the black γ-phase is shown to behave harmonically around equilibrium, for the tetragonal phase, density functional theory reveals the same anharmonic behavior, with a Brillouin zone-centered double-well instability, as for the cubic phase. Using total energy and vibrational entropy calculations, we highlight the competition between all the low-temperature phases of CsPbI 3 (γ, δ, β) and show that avoiding the order-disorder entropy term arising from double-well instabilities is key to preventing the formation of the yellow perovskitoid phase. A symmetry-based tight-binding model, validated by self-consistent GW calculations including spin-orbit coupling, affords further insight into their electronic properties, with evidence of Rashba effect for both cubic and tetragonal phases when using the symmetry-breaking structures obtained through frozen phonon calculations.

Micro-PIXE evaluation of radioactive cesium transfer in contaminated soil samples

NASA Astrophysics Data System (ADS)

Fujishiro, F.; Ishii, K.; Matsuyama, S.; Arai, H.; Ishizaki, A.; Osada, N.; Sugai, H.; Kusano, K.; Nozawa, Y.; Yamauchi, S.; Karahashi, M.; Oshikawa, S.; Kikuchi, K.; Koshio, S.; Watanabe, K.; Suzuki, Y.

2014-01-01

Micro-PIXE analysis has been performed on two soil samples with high cesium activity concentrations. These soil samples were contaminated by fallout from the accident at Fukushima Daiichi Nuclear Power Plant. One exhibits a radioactive cesium transfer of ˜0.01, and the other shows a radioactive cesium transfer of less than 0.001, even though both samples have high cesium activity concentrations exceeding 10,000 Bq/kg. X-ray spectra and elemental images of the soil samples revealed the presence of chlorine, which can react with cesium to produce an inorganic soluble compound, and phosphorus-containing cesium-capturable organic compounds.

Methods of producing cesium-131

DOEpatents

Meikrantz, David H; Snyder, John R

2012-09-18

Methods of producing cesium-131. The method comprises dissolving at least one non-irradiated barium source in water or a nitric acid solution to produce a barium target solution. The barium target solution is irradiated with neutron radiation to produce cesium-131, which is removed from the barium target solution. The cesium-131 is complexed with a calixarene compound to separate the cesium-131 from the barium target solution. A liquid:liquid extraction device or extraction column is used to separate the cesium-131 from the barium target solution.

Cesium vapor thermionic converter anomalies arising from negative ion emission

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rasor, Ned S., E-mail: ned.rasor@gmail.com

2016-08-14

Compelling experimental evidence is given that a longstanding limit encountered on cesium vapor thermionic energy converter performance improvement and other anomalies arise from thermionic emission of cesium negative ions. It is shown that the energy that characterizes thermionic emission of cesium negative ions is 1.38 eV and, understandably, is not the electron affinity 0.47 eV determined for the photodetachment threshold of the cesium negative ion. The experimental evidence includes measurements of collector work functions and volt-ampere characteristics in quasi-vacuum cesium vapor thermionic diodes, along with reinterpretation of the classic Taylor-Langmuir S-curve data on electron emission in cesium vapor. The quantitative effects ofmore » negative ion emission on performance in the ignited, unignited, and quasi-vacuum modes of cesium vapor thermionic converter operation are estimated.« less

Radionuclide Basics: Cesium-137

EPA Pesticide Factsheets

The most common radioactive form of cesium (chemical symbol Cs) is Cesium-137. Cesium-137 is produced by nuclear fission for use in medical devices and gauges and is one of the byproducts of nuclear fission in nuclear reactors and nuclear weapons testing.

Synthesis, Characterization, Tautomeric Structure and Solvatochromic Behavior of Novel 4-(5-Arylazo-2-Hydroxystyryl)-1-Methylpyridinium Iodide as Potential Molecular Photoprobe

PubMed Central

Altalbawy, Farag; Darwish, Elham; Medhat, Mohamed; El-Zaiat, Sayed; Saleh, Hagar

2016-01-01

A novel series of the title compound 4-(5-arylazo-2-hydroxystyryl)-1-methylpyridinium iodide 6 has been synthesized via condensation reactions of the arylazosalicylaldehyde derivatives 4a–i with 1-methyl-picolinium iodide 5. The structures of the new arylazo compounds were characterized by 1H NMR, IR, mass spectroscopy, as well as spectral and elemental analyses. The electronic absorption spectra of arylazomerocyanine compounds 6 were measured in different buffer solutions and solvents. The pK′s and pK*′s in both the ground and excited states, respectively, were determined for the series and their correlations with the Hammett equation were examined. The results indicated that the title arylazomerocyanine dyes 6 exist in the azo form 6A in both ground and excited states. The substituent and solvent effects (solvatochromism) of the title compound arylazomerocyanine dyes were determined using the Kamlet-Taft equation and subsequently discussed. PMID:28774142

Synthesis, Characterization, Tautomeric Structure and Solvatochromic Behavior of Novel 4-(5-Arylazo-2-Hydroxystyryl)-1-Methylpyridinium Iodide as Potential Molecular Photoprobe.

PubMed

Altalbawy, Farag; Darwish, Elham; Medhat, Mohamed; El-Zaiat, Sayed; Saleh, Hagar

2016-12-19

A novel series of the title compound 4-(5-arylazo-2-hydroxystyryl)-1-methylpyridinium iodide 6 has been synthesized via condensation reactions of the arylazosalicylaldehyde derivatives 4a - i with 1-methyl-picolinium iodide 5 . The structures of the new arylazo compounds were characterized by ¹H NMR, IR, mass spectroscopy, as well as spectral and elemental analyses. The electronic absorption spectra of arylazomerocyanine compounds 6 were measured in different buffer solutions and solvents. The pK's and pK*'s in both the ground and excited states, respectively, were determined for the series and their correlations with the Hammett equation were examined. The results indicated that the title arylazomerocyanine dyes 6 exist in the azo form 6A in both ground and excited states. The substituent and solvent effects (solvatochromism) of the title compound arylazomerocyanine dyes were determined using the Kamlet-Taft equation and subsequently discussed.

Solution-Phase Synthesis of Cesium Lead Halide Perovskite Nanowires.

PubMed

Zhang, Dandan; Eaton, Samuel W; Yu, Yi; Dou, Letian; Yang, Peidong

2015-07-29

Halide perovskites have attracted much attention over the past 5 years as a promising class of materials for optoelectronic applications. However, compared to hybrid organic-inorganic perovskites, the study of their pure inorganic counterparts, like cesium lead halides (CsPbX3), lags far behind. Here, a catalyst-free, solution-phase synthesis of CsPbX3 nanowires (NWs) is reported. These NWs are single-crystalline, with uniform growth direction, and crystallize in the orthorhombic phase. Both CsPbBr3 and CsPbI3 are photoluminescence active, with composition-dependent temperature and self-trapping behavior. These NWs with a well-defined morphology could serve as an ideal platform for the investigation of fundamental properties and the development of future applications in nanoscale optoelectronic devices based on all-inorganic perovskites.

10 CFR 33.100 - Schedule A.

Code of Federal Regulations, 2012 CFR

2012-01-01

...-126 .1 .001 Iodine-129 .1 .01 Iodine-131 .1 .001 Iodine-132 10 .1 Iodine-133 1 .01 Iodine-134 10 .1...-125 1 .01 Arsenic-73 10 .1 Arsenic-74 1 .01 Arsenic-76 1 .01 Arsenic-77 10 .1 Barium-131 10 .1 Barium... Cerium-144 .1 .001 Cesium-131 100 1. Cesium-134m 100 1. Cesium-134 .1 .001 Cesium-135 1 .01 Cesium-136 10...

10 CFR 33.100 - Schedule A.

Code of Federal Regulations, 2014 CFR

2014-01-01

...-126 .1 .001 Iodine-129 .1 .01 Iodine-131 .1 .001 Iodine-132 10 .1 Iodine-133 1 .01 Iodine-134 10 .1...-125 1 .01 Arsenic-73 10 .1 Arsenic-74 1 .01 Arsenic-76 1 .01 Arsenic-77 10 .1 Barium-131 10 .1 Barium... Cerium-144 .1 .001 Cesium-131 100 1. Cesium-134m 100 1. Cesium-134 .1 .001 Cesium-135 1 .01 Cesium-136 10...

10 CFR 33.100 - Schedule A.

Code of Federal Regulations, 2013 CFR

2013-01-01

...-126 .1 .001 Iodine-129 .1 .01 Iodine-131 .1 .001 Iodine-132 10 .1 Iodine-133 1 .01 Iodine-134 10 .1...-125 1 .01 Arsenic-73 10 .1 Arsenic-74 1 .01 Arsenic-76 1 .01 Arsenic-77 10 .1 Barium-131 10 .1 Barium... Cerium-144 .1 .001 Cesium-131 100 1. Cesium-134m 100 1. Cesium-134 .1 .001 Cesium-135 1 .01 Cesium-136 10...

Method and article for primary containment of cesium wastes. [DOE patent application

DOEpatents

Angelini, P.; Lackey, W.J.; Stinton, D.P.; Blanco, R.E.; Bond, W.D.; Arnold, W.D. Jr.

1981-09-03

A method for producing a cesium-retentive waste form, characterized by a high degree of compositional stability and mechanical integrity, is provided by subjecting a cesium-loaded zeolite to heat under conditions suitable for stabilizing the zeolite and immobilizing the cesium, and coating said zeolite for sufficient duration within a suitable environment with at least one dense layer of pyrolytic carbon to seal therein said cesium to produce a final, cesium-bearing waste form. Typically, the zolite is stabilized and the cesium immobilized in less than four hours by confinement within an air environment maintained at about 600/sup 0/C. Coatings are thereafter applied by confining the calcined zeolite within a coating environment comprising inert fluidizing and carbon donor gases maintained at 1000/sup 0/C for a suitable duration.

Method for primary containment of cesium wastes

DOEpatents

Angelini, Peter; Lackey, Walter J.; Stinton, David P.; Blanco, Raymond E.; Bond, Walter D.; Arnold, Jr., Wesley D.

1983-01-01

A method for producing a cesium-retentive waste form, characterized by a high degree of compositional stability and mechanical integrity, is provided by subjecting a cesium-loaded zeolite to heat under conditions suitable for stabilizing the zeolite and immobilizing the cesium, and coating said zeolite for sufficient duration within a suitable environment with at least one dense layer of pyrolytic carbon to seal therein said cesium to produce a final, cesium-bearing waste form. Typically, the zeolite is stabilized and the cesium immobilized in less than four hours by confinement within an air environment maintained at about 600.degree. C. Coatings are thereafter applied by confining the calcined zeolite within a coating environment comprising inert fluidizing and carbon donor gases maintained at 1,000.degree. C. for a suitable duration.

The iodide space in rabbit brain

PubMed Central

Ahmed, Nawal; Van Harreveld, A.

1969-01-01

1. The iodide space in rabbit brain varies greatly depending on the conditions under which it is determined. 2. When 131I- only is used the iodide space 4 hr after administration of the marker is of the order of 2%. The iodide content of the cerebrospinal fluid (c.s.f.) is about 1% of that of the serum. 3. Depression of the active iodide transport by perchlorate increases the space to 8·2% and the iodide content of the c.s.f. to 26% of that of the serum. 4. The active iodide transport can also be depressed by saturation with unlabelled iodide. Up to a serum iodide concentration of 5 mM the space determined after 5 hr remained constant at 2·7%. The iodide space grew when the serum iodide content was enhanced from 5 to 20 mM, to become constant at a value of 10·6% on further increase of the serum iodide (up to 50 mM). The iodide content of the c.s.f. increased in a similar manner as the space with the iodide concentration of the serum to about 1/3 of the serum concentration. The iodide space of the muscle was independent of the plasma iodide content. 5. From 4 to 8 hr after administration of 131I- alone or with unlabelled iodide (to a serum concentration of 15 mM) the iodide space remained relatively constant. 6. When 131I- was administered in the fluid with which the ventricles were perfused an iodide space of about 7% was attained after about 5 hr. 7. In experiments in which 131I- was administered intravenously and the sink action of the c.s.f. was eliminated by perfusion of the ventricles with a perfusate containing as much 131I- as the plasma, the iodide space was 10·2%. When in addition active iodide transport was depressed by perchlorate the space increased to 16·8%. 8. Intravenous administration of labelled and unlabelled iodide (to a serum concentration of 20-40 mM) and ventricle perfusion with the same concentration of 131I- and unlabelled iodide as in the plasma yielded an iodide space of 20·8%. In similar experiments the iodide concentration of the perfusate was so adjusted that after 5 hr perfusion its iodide content hardly changed during the passage through the ventricles. Under these conditions the iodide concentration of the extracellular and perfusion fluids can be considered to be near equal. The iodide space computed on the basis of the iodide content of the outflowing fluid was 22·5%. 9. The large iodide space could be equated with the extracellular space if the iodide remained extracellular. This seems to be the case in the muscle where the iodide space is similar to the inulin space. 10. The large effects on the iodide space of perchlorate and saturation with unlabelled iodide in experiments in which the marker was administered intravenously and in the perfusate (7 and 8) suggests the presence of an active iodide transport from the brain extracellular fluid into the blood over the blood—brain barrier. PMID:4310942

Ion-Specific Induced Fluctuations and Free Energetics of Aqueous Protein Hydrophobic Interfaces: Toward Connecting to Specific-Ion Behaviors at Aqueous Liquid–Vapor Interfaces

PubMed Central

2015-01-01

We explore anion-induced interface fluctuations near protein–water interfaces using coarse-grained representations of interfaces as proposed by Willard and Chandler (J. Phys. Chem. B2010, 114, 1954−195820055377). We use umbrella sampling molecular dynamics to compute potentials of mean force along a reaction coordinate bridging the state where the anion is fully solvated and one where it is biased via harmonic restraints to remain at the protein–water interface. Specifically, we focus on fluctuations of an interface between water and a hydrophobic region of hydrophobin-II (HFBII), a 71 amino acid residue protein expressed by filamentous fungi and known for its ability to form hydrophobically mediated self-assemblies at interfaces such as a water/air interface. We consider the anions chloride and iodide that have been shown previously by simulations as displaying specific-ion behaviors at aqueous liquid–vapor interfaces. We find that as in the case of a pure liquid–vapor interface, at the hydrophobic protein–water interface, the larger, less charge-dense iodide anion displays a marginal interfacial stability compared with that of the smaller, more charge-dense chloride anion. Furthermore, consistent with the results at aqueous liquid–vapor interfaces, we find that iodide induces larger fluctuations of the protein–water interface than chloride. PMID:24701961

REMOVAL OF CESIUM BY SORPTION FROM AQUEOUS SOLUTIONS

DOEpatents

Ames, L.L.

1962-01-16

ABS>A process is given for selectively removing cesium from acid aqueous solutions containing cesium in microquantities and other cations in macroquantities by absorption on clinoptilolite. The cesium can be eluted from the clinoptilolite with a solution of ammonia, potassium hydroxide, or rubidium hydroxide. (AEC)

An Experimental Study of the Fluorescence Spectrum of Cesium Atoms in the Presence of a Buffer Gas

NASA Astrophysics Data System (ADS)

Davydov, V. G.; Kulyasov, V. N.

2018-01-01

A direct experiment is performed to determine the quantum efficiency of a cesium fluorescence filter. The fluorescence spectra of cesium atoms are recorded under excitation of the upper states of the second resonance doublet with a Bell-Bloom cesium lamp. Introduction of different noble gases into the cell with cesium leads to the appearance of additional fluorescence photons. It is found that a fluorescence filter based on atomic cesium vapor with addition of helium in the working cell has the highest efficiency and response rate of all known fluorescence filters based on alkali-metal atomic vapors.

Behavior of toxic metals and radionuclides during molten salt oxidation of chlorinated plastics.

PubMed

Yang, Hee-Chul; Cho, Yong-Jun; Eun, Hee-Chul; Yoo, Jae-Hyung; Kim, Joon-Hyung

2004-01-01

Molten salt oxidation is one of the promising alternatives to incineration for chlorinated organics without the emission of chlorinated organic pollutants. This study investigated the behavior of three hazardous metals (Cd, Pb, and Cr) and four radioactive metal surrogates (Cs, Ce, Gd, and Sm) in the molten Na2CO3 oxidation reactor during the destruction of PVC plastics. In the tested temperature ranges (1143 1223K) and NaCl content (0-10%), the impact of temperature on the retention of cadmium and lead in the molten salt reactor was very small, but that of the NaCl content for their retention was relatively higher. The influence of NaCl accumulation was, however, proven to be practically negligible due to the low-temperature operating characteristics of the molten salt oxidation system. Neither temperature increase nor chlorine accumulation in the MSO reactor reduced the retention of Cr, Ce, Gd, and Sm. Over 99.98% of these metals remained in the reactor. The influence of the temperature on the cesium behavior is relatively large for a chlorine addition, however, over 99.7% of cesium remained in the reactor throughout the entire test. The experimental metal entrainment rate and the entrained metal particle size distribution agree well with the theoretical equilibrium metal distributions.

Process for cesium decontamination and immobilization

DOEpatents

Komarneni, Sridhar; Roy, Rustum

1989-01-01

Cesium can be selectively recovered from a nuclear waste solution containing cesium together with other metal ions by contact with a modified phlogopite which is a hydrated, sodium phlogopite mica. Once the cesium has entered the modified phlogopite it is fixed and can be safely stored for long periods of time.

Method of removing cesium from steam

DOEpatents

Carson, Jr., Neill J.; Noland, Robert A.; Ruther, Westly E.

1991-01-01

Method for removal of radioactive cesium from a hot vapor, such as high temperature steam, including the steps of passing input hot vapor containing radioactive cesium into a bed of silicate glass particles and chemically incorporating radioactive cesium in the silicate glass particles at a temperature of at least about 700.degree. F.

Cesium Sorption/Desorption Experiments with IONSIV(R) IE-911 in Radioactive Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, D.D.

2001-02-13

This report describes cesium desorption from IONSIV IE-911 during ambient temperature storage and following temperature increases to 35 and 55 degrees C. This report also describes cesium sorption following return to ambient temperature. The IONSIV IE-911 used in these tests was loaded with cesium from Tank 44F radioactive waste in an ion exchange column test in 1999. Cesium desorbed and resorbed in the presence of Tank 44F waste and simulated waste solutions.

Long Duration Responses in Squid Giant Axons Injected with 134Cesium Sulfate Solutions

PubMed Central

Sjodin, R. A.

1966-01-01

Giant axons from the squid were injected with 1.5 M cesium sulfate solutions containing the radioactive isotopes 42K and 134Cs. These axons, when stimulated, gave characteristic long duration action potentials lasting between 5 and 45 msec. The effluxes of 42K and 134Cs were measured both under resting conditions and during periods of repetitive stimulation. During the lengthened responses there were considerable increases in potassium efflux but only small increases in cesium efflux. The selectivity of the delayed rectification process was about 9 times greater for potassium ions than for cesium ions. The data suggest that internal cesium ions inhibit the outward potassium movement occurring during an action potential. The extra potassium effluxes taking place during excitation appear to be reduced in the presence of cesium ions to values between 7 and 22% of those expected in the absence of cesium inhibition. PMID:11526828

Process for cesium decontamination and immobilization

DOEpatents

Komarneni, S.; Roy, R.

1988-04-25

Cesium can be selectively recovered from a nuclear waste solution containing cesium together with other metal ions by contact with a modified phlogopite which is a hydrated, sodium phlogopite mica. Once the cesium has entered the modified phlogopite it is fixed and can be safely stored for long periods of time. 6 figs., 2 tabs.

Measurements of the cesium flow from a surface-plasma H/sup -/ ion source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, H.V.; Allison, P.W.

1979-01-01

A surface ionization gauge (SIG) was constructed and used to measure the Cs/sup 0/ flow rate through the emission slit of a surface-plasma source (SPS) of H/sup -/ ions with Penning geometry. The equivalent cesium density in the SPS discharge is deduced from these flow measurements. For dc operation the optimum H/sup -/ current occurs at an equivalent cesium density of approx. 7 x 10/sup 12/ cm/sup -3/ (corresponding to an average cesium consumption rate of 0.5 mg/h). For pulsed operation the optimum H/sup -/ current occurs at an equivalent cesium density of approx. 2 x 10/sup 13/ cm/sup -3/more » (1-mg/h average cesium consumption rate). Cesium trapping by the SPS discharge was observed for both dc and pulsed operation. A cesium energy of approx. 0.1 eV is deduced from the observed time of flight to the SIG. In addition to providing information on the physics of the source, the SIG is a useful diagnostic tool for source startup and operation.« less

Re-suspension of Cesium-134/137 into the Canadian Environment and the Contribution Stemming from the Fukushima-Daiichi Nuclear Incident

NASA Astrophysics Data System (ADS)

Mercier, Jean-Francois; Zhang, Weihua; Loignon-Houle, Francis; Cooke, Michael W.; Ungar, Kurt R.; Pellerin, Eric R.

2013-04-01

Cesium-137 (t1/2 = 30 yr) and cesium-134 (t1/2 = 2yr) constitute major fission by-products observed as the result of a nuclear incident. Such radioisotopes become integrated into the soil and biomass, and can therefore undergo re-suspension into the environment via activities such as forest fires. The Canadian Radiological Monitoring Network (CRMN), which consists of 26 environmental monitoring stations spread across the country, commonly observes cesium-137 in air filters due to re-suspension of material originating from long-past weapons testing. Cesium-134 is not observed owing to its relatively short half-life. The Fukushima-Daiichi nuclear power plant incident of March 2011 caused a major release of radioactive materials into the environment. In Canada, small quantities of both cesium-137 and cesium-134 fallout were detected with great frequency in the weeks which followed, falling off rapidly beginning in July 2011. Since September 2011, the CRMN has detected both cesium-137 and cesium-134 from air filters collected at Yellowknife, Resolute, and Quebec City locations. Using the known initial cesium-134/cesium-137 ratio stemming from this incident, along with a statistical assessment of the normality of the data distribution, we herein present evidence that strongly suggests that these activity spikes are due to re-suspended hot particles originating from the Fukushima-Daiichi nuclear power plant incident. Moreover, we have evidence to suggest that this re-suspension is localized in nature. This study provided empirical insight into the transport and uptake of radionuclides over vast distances, and it demonstrates that the CRMN was able to detect evidence of a re-suspension of Fukushima-Daiichi related isotopes.

Cesium Uptake by Rice Roots Largely Depends Upon a Single Gene, HAK1, Which Encodes a Potassium Transporter.

PubMed

Rai, Hiroki; Yokoyama, Saki; Satoh-Nagasawa, Namiko; Furukawa, Jun; Nomi, Takiko; Ito, Yasuka; Fujimura, Shigeto; Takahashi, Hidekazu; Suzuki, Ryuichiro; Yousra, ELMannai; Goto, Akitoshi; Fuji, Shinichi; Nakamura, Shin-Ichi; Shinano, Takuro; Nagasawa, Nobuhiro; Wabiko, Hiroetsu; Hattori, Hiroyuki

2017-09-01

Incidents at the Fukushima and Chernobyl nuclear power stations have resulted in widespread environmental contamination by radioactive nuclides. Among them, 137cesium has a 30 year half-life, and its persistence in soil raises serious food security issues. It is therefore important to prevent plants, especially crop plants, from absorbing radiocesium. In Arabidopsis thaliana, cesium ions are transported into root cells by several different potassium transporters such as high-affinity K+ transporter 5 (AtHAK5). Therefore, the cesium uptake pathway is thought to be highly redundant, making it difficult to develop plants with low cesium uptake. Here, we isolated rice mutants with low cesium uptake and reveal that the Oryza sativa potassium transporter OsHAK1, which is expressed on the surfaces of roots, is the main route of cesium influx into rice plants, especially in low potassium conditions. During hydroponic cultivation with low to normal potassium concentrations (0-206 µM: the normal potassium level in soil), cesium influx in OsHAK1-knockout lines was no greater than one-eighth that in the wild type. In field experiments, knockout lines of O. sativa HAK1 (OsHAK1) showed dramatically reduced cesium concentrations in grains and shoots, but their potassium uptake was not greatly affected and their grain yields were similar to that of the wild type. Our results demonstrate that, in rice roots, potassium transport systems other than OsHAK1 make little or no contribution to cesium uptake. These results show that low cesium uptake rice lines can be developed for cultivation in radiocesium-contaminated areas. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

EUV observation from the Earth-orbiting satellite, EXCEED

NASA Astrophysics Data System (ADS)

Yoshioka, K.; Murakami, G.; Yoshikawa, I.; Ueno, M.; Uemizu, K.; Yamazaki, A.

2010-01-01

An Earth-orbiting small satellite “EXtreme ultraviolet spectrosCope for ExosphEric Dynamics” (EXCEED) which will be launched in 2012 is under development. The mission will carry out spectroscopic and imaging observation of EUV (Extreme Ultraviolet: 60-145 nm) emissions from tenuous plasmas around the planets (Venus, Mars, Mercury, and Jupiter). It is essential for EUV observation to put on an observing site outside the Earth’s atmosphere to avoid the absorption. It is also essential that the detection efficiency must be very high in order to catch the faint signals from those targets. In this mission, we employ cesium iodide coated microchannel plate as a 2 dimensional photon counting devise which shows 1.5-50 times higher quantum detection efficiency comparing with the bared one. We coat the surface of the grating and entrance mirror with silicon carbides by the chemical vapor deposition method in order to archive the high diffraction efficiency and reflectivity. The whole spectrometer is shielded by the 2 mm thick stainless steel to prevent the contamination caused by the high energy electrons from the inner radiation belt. In this paper, we will introduce the mission overview, its instrument, and their performance.

Gamma ray camera

DOEpatents

Perez-Mendez, V.

1997-01-21

A gamma ray camera is disclosed for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array. 6 figs.

Gamma ray camera

DOEpatents

Perez-Mendez, Victor

1997-01-01

A gamma ray camera for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array.

Si-strip photon counting detectors for contrast-enhanced spectral mammography

NASA Astrophysics Data System (ADS)

Chen, Buxin; Reiser, Ingrid; Wessel, Jan C.; Malakhov, Nail; Wawrzyniak, Gregor; Hartsough, Neal E.; Gandhi, Thulasi; Chen, Chin-Tu; Iwanczyk, Jan S.; Barber, William C.

2015-08-01

We report on the development of silicon strip detectors for energy-resolved clinical mammography. Typically, X-ray integrating detectors based on scintillating cesium iodide CsI(Tl) or amorphous selenium (a-Se) are used in most commercial systems. Recently, mammography instrumentation has been introduced based on photon counting Si strip detectors. The required performance for mammography in terms of the output count rate, spatial resolution, and dynamic range must be obtained with sufficient field of view for the application, thus requiring the tiling of pixel arrays and particular scanning techniques. Room temperature Si strip detector, operating as direct conversion x-ray sensors, can provide the required speed when connected to application specific integrated circuits (ASICs) operating at fast peaking times with multiple fixed thresholds per pixel, provided that the sensors are designed for rapid signal formation across the X-ray energy ranges of the application. We present our methods and results from the optimization of Si-strip detectors for contrast enhanced spectral mammography. We describe the method being developed for quantifying iodine contrast using the energy-resolved detector with fixed thresholds. We demonstrate the feasibility of the method by scanning an iodine phantom with clinically relevant contrast levels.

Highly stable cesium lead iodide perovskite quantum dot light-emitting diodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zou, Chen; Huang, Chun-Ying; Sanehira, Erin M.

Recently, all-inorganic perovskites such as CsPbBr3 and CsPbI3, have emerged as promising materials for light-emitting applications. While encouraging performance has been demonstrated, the stability issue of the red-emitting CsPbI3 is still a major concern due to its small tolerance factor. Here we report a highly stable CsPbI3 quantum dot LED with red emission fabricated using an improved purification approach. The device achieved decent external quantum efficiency (EQE) of 0.21 % at a bias of 6 V and outstanding operational stability, with a L70 lifetime (EL intensity decreases to 70% of starting value) of 16 h and 1.5 h under amore » constant driving voltage of 5 V and 6 V (maximum EQE operation) respectively. Furthermore, the device can work under a higher voltage of 7 V (maximum luminance operation) and retain 50% of its initial EL intensity after 500 s. These findings demonstrate the promise of CsPbI3 quantum dots for stable red LEDs, and suggest the feasibility for electrically pumped perovskite lasers with further device optimizations.« less

Methods for collection and analysis of geopressured geothermal and oil field waters

USGS Publications Warehouse

Lico, Michael S.; Kharaka, Yousif K.; Carothers, William W.; Wright, Victoria A.

1982-01-01

Present methods are described for the collection, preservation, and chemical analysis of waters produced from geopressured geothermal and petroleum wells. Detailed procedures for collection include precautions and equipment necessary to ensure that the sample is representative of the water produced. Procedures for sample preservation include filtration, acidification, dilution for silica, methyl isobutyl ketone (MIBK) extraction of aluminum, addition of potassium permanganate to preserve mercury, and precipitation of carbonate species as strontium carbonate for stable carbon isotopes and total dissolved carbonate analysis. Characteristics determined at the well site are sulfide, pH, ammonia, and conductivity. Laboratory procedures are given for the analysis of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, iron, manganese, zinc, lead, aluminum, .and mercury by atomic absorption and flame emission spectroscopy. Chloride is determined by silver nitrate titration and fluoride by ion-specific electrode. Bromide and iodide concentrations are determined by the hypochlorite oxidation method. Sulfate is analyzed by titration using barium chloride with thorin indicator after pretreatment with alumina. Boron and silica are determined colorimetrically by the carmine and molybdate-blue methods, respectively. Aliphatic acid anions (C2 through C5) are determined by gas chromatography after separation and concentration in a chloroform-butanol mixture.

Validation of columnar CsI x-ray detector responses obtained with hybridMANTIS, a CPU-GPU Monte Carlo code for coupled x-ray, electron, and optical transport

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Diksha; Badano, Aldo

2013-03-15

Purpose: hybridMANTIS is a Monte Carlo package for modeling indirect x-ray imagers using columnar geometry based on a hybrid concept that maximizes the utilization of available CPU and graphics processing unit processors in a workstation. Methods: The authors compare hybridMANTIS x-ray response simulations to previously published MANTIS and experimental data for four cesium iodide scintillator screens. These screens have a variety of reflective and absorptive surfaces with different thicknesses. The authors analyze hybridMANTIS results in terms of modulation transfer function and calculate the root mean square difference and Swank factors from simulated and experimental results. Results: The comparison suggests thatmore » hybridMANTIS better matches the experimental data as compared to MANTIS, especially at high spatial frequencies and for the thicker screens. hybridMANTIS simulations are much faster than MANTIS with speed-ups up to 5260. Conclusions: hybridMANTIS is a useful tool for improved description and optimization of image acquisition stages in medical imaging systems and for modeling the forward problem in iterative reconstruction algorithms.« less

A low cost method for hard x-ray grating interferometry.

PubMed

Du, Yang; Lei, Yaohu; Liu, Xin; Huang, Jianheng; Zhao, Zhigang; Guo, Jinchuan; Li, Ji; Niu, Hanben

2016-12-07

Grating interferometry is advantageous over conventional x-ray absorption imaging because it enables the detection of samples constituted by low atomic number elements (low-Z materials). Therefore, it has a potential application in biological science and medical diagnostics. The grating interferometry has some critical optics components such as absorption gratings which are conventionally manufactured by the lithography, electroplating, and molding (LIGA) technique and employing gold as the absorbent material in it. However, great challenge lies in its implementations for practical applications because of the cost and difficulty to achieve high aspect ratio absorbing grating devices. In this paper, we present a low-cost approach that involves using the micro-casting technique with bismuth (Bi) as the absorber in source grating and as well as filling cesium iodide thallium(CsI:Tl) in a periodically structured scintillator. No costly facilities as synchrotron radiation are required and cheap material is used in our approach. Our experiment using these components shows high quality complementary images can be obtained with contrast of absorption, phase and visibility. This alternative method conquers the limitation of costly grating devices for a long time and stands an important step towards the further practical application of grating interferometry.

Highly stable cesium lead iodide perovskite quantum dot light-emitting diodes

DOE PAGES

Zou, Chen; Huang, Chun-Ying; Sanehira, Erin M.; ...

2017-09-11

Recently, all-inorganic perovskites such as CsPbBr3 and CsPbI3, have emerged as promising materials for light-emitting applications. While encouraging performance has been demonstrated, the stability issue of the red-emitting CsPbI3 is still a major concern due to its small tolerance factor. Here we report a highly stable CsPbI3 quantum dot LED with red emission fabricated using an improved purification approach. The device achieved decent external quantum efficiency (EQE) of 0.21 % at a bias of 6 V and outstanding operational stability, with a L70 lifetime (EL intensity decreases to 70% of starting value) of 16 h and 1.5 h under amore » constant driving voltage of 5 V and 6 V (maximum EQE operation) respectively. Furthermore, the device can work under a higher voltage of 7 V (maximum luminance operation) and retain 50% of its initial EL intensity after 500 s. These findings demonstrate the promise of CsPbI3 quantum dots for stable red LEDs, and suggest the feasibility for electrically pumped perovskite lasers with further device optimizations.« less

Method for synthesizing pollucite from chabazite and cesium chloride

DOEpatents

Pereira, C.

1999-02-23

A method is described for immobilizing waste chlorides salts containing radionuclides and hazardous nuclear material for permanent disposal, and in particular, a method is described for immobilizing waste chloride salts containing cesium, in a synthetic form of pollucite. The method for synthesizing pollucite from chabazite and cesium chloride includes mixing dry, non-aqueous cesium chloride with chabazite and heating the mixture to a temperature greater than the melting temperature of the cesium chloride, or above about 700 C. The method further comprises significantly improving the rate of retention of cesium in ceramic products comprised of a salt-loaded zeolite by adding about 10% chabazite by weight to the salt-loaded zeolite prior to conversion at elevated temperatures and pressures to the ceramic composite. 3 figs.

Method for synthesizing pollucite from chabazite and cesium chloride

DOEpatents

Pereira, Candido

1999-01-01

A method for immobilizing waste chlorides salts containing radionuclides and hazardous nuclear material for permanent disposal, and in particular, a method for immobilizing waste chloride salts containing cesium, in a synthetic form of pollucite. The method for synthesizing pollucite from chabazite and cesium chloride includes mixing dry, non-aqueous cesium chloride with chabazite and heating the mixture to a temperature greater than the melting temperature of the cesium chloride, or above about 700.degree. C. The method further comprises significantly improving the rate of retention of cesium in ceramic products comprised of a salt-loaded zeolite by adding about 10% chabazite by weight to the salt-loaded zeolite prior to conversion at elevated temperatures and pressures to the ceramic composite.

Application Status of Rubidium, Cesium and Research Situation of its Separation from Brine with Solvent Extraction

NASA Astrophysics Data System (ADS)

Shi, Zhen; Du, Xuemin; Wang, Shiqiang; Guo, Yafei; Deng, Tianlong

2017-12-01

Rubidium, cesium and its compounds play an important role in traditional and high-tech fields. This paper focuses on the research status of separation rubidium and cesium in brine using solvent extraction, and briefly introduced the characteristics of this method, which can be used to realize industrial production of rubidium and cesium from brine.

Removal of Cs+ from water and soil by ammonium-pillared montmorillonite/Fe3O4 composite.

PubMed

Zheng, Xianming; Dou, Junfeng; Yuan, Jing; Qin, Wei; Hong, Xiaoxi; Ding, Aizhong

2017-06-01

To remove cesium ions from water and soil, a novel adsorbent was synthesized by following a one-step co-precipitation method and using non-toxic raw materials. By combining ammonium-pillared montmorillonite (MMT) and magnetic nanoparticles (Fe 3 O 4 ), an MMT/Fe 3 O 4 composite was prepared and characterized. The adsorbent exhibited high selectivity of Cs + and could be rapidly separated from the mixed solution under an external magnetic field. Above all, the adsorbent had high removal efficiency in cesium-contaminated samples (water and soil) and also showed good recycling performance, indicating that the MMT/Fe 3 O 4 composite could be widely applied to the remediation of cesium-contaminated environments. It was observed that the pH, solid/liquid ratio and initial concentration affected adsorption capacity. In the presence of coexisting ions, the adsorption capacity decreased in the order of Ca 2+ >Mg 2+ >K + >Na + , which is consistent with our theoretical prediction. The adsorption behavior of this new adsorbent could be expressed by the pseudo-second-order model and Freundlich isotherm. In addition, the adsorption mechanism of Cs + was NH 4 + ion exchange and surface hydroxyl group coordination, with the former being more predominant. Copyright © 2016. Published by Elsevier B.V.

Improvement of N-phthaloylchitosan based gel polymer electrolyte in dye-sensitized solar cells using a binary salt system.

PubMed

Yusuf, S N F; Azzahari, A D; Selvanathan, V; Yahya, R; Careem, M A; Arof, A K

2017-02-10

A binary salt system utilizing lithium iodide (LiI) as the auxiliary component has been introduced to the N-phthaloylchitosan (PhCh) based gel polymer electrolyte consisting of ethylene carbonate (EC), dimethylformamide (DMF), tetrapropylammonium iodide (TPAI), and iodine (I 2 ) in order to improve the performance of dye-sensitized solar cell (DSSC) with efficiency of 6.36%, photocurrent density, J SC of 17.29mAcm -2 , open circuit voltage, V OC of 0.59V and fill factor, FF of 0.62. This efficiency value is an improvement from the 5.00% performance obtained by the DSSC consisting of only TPAI single salt system. The presence of the LiI in addition to the TPAI improves the charge injection rates and increases the iodide contribution to the total conductivity and both factors contribute to the increase in efficiency of the DSSC. The interaction behavior between polymer-plasticizer-salt was thoroughly investigated using EIS, FTIR spectroscopy and XRD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterization of thermally evaporated lead iodide films aimed for the detection of X-rays

NASA Astrophysics Data System (ADS)

Caldeira Filho, A. M.; Mulato, M.

2011-04-01

Some semiconductor materials such as lead iodide (PbI2) have applications in the detection of ionizing radiation at room temperature using the direct detection method. In this work we investigate lead iodide films deposited by thermal evaporation. The morphology, structure, and electric properties were investigated as a function of deposition height, i.e. the distance between evaporation-boat and substrates. The results show a morphology of vertical leaves and X-ray diffraction shows just one preferential orientation along the direction 110. Energy dispersive spectroscopy reveals that the films are not stoichiometric, with excess iodine atoms. Electrical resistivity of about 108 Ω cm was measured. This is smaller than for the bulk due to structural defects. The values of activation energy for electric transport increase from 0.52 up to 1.1 eV with decreasing deposition height, what indicates that the best film is the one deposited at the shortest distance. Exposure under X-ray mammographic energy shows a linear behavior up to 500 mR. No variation in sensibility was observed between 22 and 30 kVp.

Fundamental x-ray interaction limits in diagnostic imaging detectors: frequency-dependent Swank noise.

PubMed

Hajdok, G; Battista, J J; Cunningham, I A

2008-07-01

A frequency-dependent x-ray Swank factor based on the "x-ray interaction" modulation transfer function and normalized noise power spectrum is determined from a Monte Carlo analysis. This factor was calculated in four converter materials: amorphous silicon (a-Si), amorphous selenium (a-Se), cesium iodide (CsI), and lead iodide (PbI2) for incident photon energies between 10 and 150 keV and various converter thicknesses. When scaled by the quantum efficiency, the x-ray Swank factor describes the best possible detective quantum efficiency (DQE) a detector can have. As such, this x-ray interaction DQE provides a target performance benchmark. It is expressed as a function of (Fourier-based) spatial frequency and takes into consideration signal and noise correlations introduced by reabsorption of Compton scatter and photoelectric characteristic emissions. It is shown that the x-ray Swank factor is largely insensitive to converter thickness for quantum efficiency values greater than 0.5. Thus, while most of the tabulated values correspond to thick converters with a quantum efficiency of 0.99, they are appropriate to use for many detectors in current use. A simple expression for the x-ray interaction DQE of digital detectors (including noise aliasing) is derived in terms of the quantum efficiency, x-ray Swank factor, detector element size, and fill factor. Good agreement is shown with DQE curves published by other investigators for each converter material, and the conditions required to achieve this ideal performance are discussed. For high-resolution imaging applications, the x-ray Swank factor indicates: (i) a-Si should only be used at low-energy (e.g., mammography); (ii) a-Se has the most promise for any application below 100 keV; and (iii) while quantum efficiency may be increased at energies just above the K edge in CsI and PbI2, this benefit is offset by a substantial drop in the x-ray Swank factor, particularly at high spatial frequencies.

Generation of gas-phase ions from charged clusters: an important ionization step causing suppression of matrix and analyte ions in matrix-assisted laser desorption/ionization mass spectrometry.

PubMed

Lou, Xianwen; van Dongen, Joost L J; Milroy, Lech-Gustav; Meijer, E W

2016-12-30

Ionization in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a very complicated process. It has been reported that quaternary ammonium salts show extremely strong matrix and analyte suppression effects which cannot satisfactorily be explained by charge transfer reactions. Further investigation of the reasons causing these effects can be useful to improve our understanding of the MALDI process. The dried-droplet and modified thin-layer methods were used as sample preparation methods. In the dried-droplet method, analytes were co-crystallized with matrix, whereas in the modified thin-layer method analytes were deposited on the surface of matrix crystals. Model compounds, tetrabutylammonium iodide ([N(Bu) 4 ]I), cesium iodide (CsI), trihexylamine (THA) and polyethylene glycol 600 (PEG 600), were selected as the test analytes given their ability to generate exclusively pre-formed ions, protonated ions and metal ion adducts respectively in MALDI. The strong matrix suppression effect (MSE) observed using the dried-droplet method might disappear using the modified thin-layer method, which suggests that the incorporation of analytes in matrix crystals contributes to the MSE. By depositing analytes on the matrix surface instead of incorporating in the matrix crystals, the competition for evaporation/ionization from charged matrix/analyte clusters could be weakened resulting in reduced MSE. Further supporting evidence for this inference was found by studying the analyte suppression effect using the same two sample deposition methods. By comparing differences between the mass spectra obtained via the two sample preparation methods, we present evidence suggesting that the generation of gas-phase ions from charged matrix/analyte clusters may induce significant suppression of matrix and analyte ions. The results suggest that the generation of gas-phase ions from charged matrix/analyte clusters is an important ionization step in MALDI-MS. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Improvement of the BiOI photocatalytic activity optimizing the solvothermal synthesis

NASA Astrophysics Data System (ADS)

Mera, Adriana C.; Moreno, Yanko; Contreras, David; Escalona, Nestor; Meléndrez, Manuel F.; Mangalaraja, Ramalinga Viswanathan; Mansilla, Héctor D.

2017-01-01

BiOI nanostructured microspheres were obtained from the solvothermal synthesis route in the presence of ethylene glycol and KI as solvent and source of iodide, respectively. Optimal conditions for the synthesis were obtained by using multivariate analysis and choosing the photocatalytic oxidation rate constant of 3,4,5-trihydroxybenzoic acid (gallic acid) as response factor under simulated solar radiation. Response surface methodology (RSM) was used to determine the optimum values of the reaction time and temperature which were 18 h and 126 °C, respectively, to obtain the most active catalyst. In addition, BiOI synthesis using ionic liquid 1-butyl-3-methylimidazolium iodide ([bmim]I) as iodide source was also carried out for the comparison of microstructure and its photocatalytic efficiency. The obtained BiOI nanostructures were characterized by scanning electron microscopy (SEM) attached with energy dispersive spectrometer (EDS), nitrogen adsorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetry (TG), Fourier transform infrared (FTIR) spectrometry, diffuse reflectance spectroscopy (DRS) and cyclic voltammetry (CV) analyses for their changes in morphological and structural behaviors. It was observed that the synthesis temperature of BiOI nanostructures strongly influenced the morphology, crystalline phase, surface area and electrochemical behavior, and thus affecting the photocatalytic efficiency. The higher photocatalytic removal of gallic acid (60%) was reached within 30 min of irradiation with UV-A on microspheres obtained with ionic liquid. The (1 1 0) crystal phase of BiOI influenced the photocatalytic efficiency.

Forcing Cesium into Higher Oxidation States Using Useful hard x-ray Induced Chemistry under High Pressure

NASA Astrophysics Data System (ADS)

Sneed, D.; Pravica, M.; Kim, E.; Chen, N.; Park, C.; White, M.

2017-10-01

This paper discusses our attempt to synthesize higher oxidation forms of cesium fluoride by pressurizing cesium fluoride in a fluorine-rich environment created via the x-ray decomposition of potassium tetrafluoroborate. This was done in order to confirm recent theoretical predictions of higher oxidation forms of CsFn. We discuss the development of a technique to produce molecular fluorine in situ via useful hard x-ray photochemistry, and the attempt to utilize this technique to form higher oxidation states of cesium fluoride. In order to verify the formation of the novel stoichiometric species of CsFn. X-ray Absorption Near Edge Spectroscopy (XANES) centered on the cesium K-edge was performed to probe the oxidation state of cesium as well as the local molecular coordination around Cs.

Evaluation of a method for removing cesium and reducing the volume of leaf litter from broad-leaved trees contaminated by the Fukushima Daiichi nuclear accident during the Great East Japan Earthquake.

PubMed

Harada, Shigeki; Yanagisawa, Mitsunori

2017-04-01

The town of Marumori in southern Miyagi Prefecture borders on Fukushima Prefecture, and following the accident at the Fukushima Daiichi nuclear power plant, there were concerns about cesium deposition in forested areas. One of the authors of this paper has continually surveyed leaf litter from the forested areas. As leaf litter may be a source of cesium contamination from the forest to downstream areas, we considered a simplified version of wet oxidation, a method previously presented by one of the authors of this study, as a technology to reduce leaf litter weight and cesium concentration, separating radioactive nuclides from non-radioactive ones, in leaf litter. We tested our method in three experiments. Experiment 1 used new leaf litter (232 Bq/kg) from the surface of a small stream at the forest edge nearby an area with air dose level higher than the national standard threshold of 0.23 μSv/h for the implementation of governmental decontamination works. Experiment 2 applied wet oxidation to older leaf litter (705 Bq/kg) harvested from a pasture nearby the stream mentioned above. We also used the same leaf litter in experiment 3 for a cesium release tests using pure water. In experiment 1 and 2 we treated leaf litter with a sodium hypochlorite solution, optimizing sodium hypochlorite concentration and reaction temperature. We measured a 50-60% decrease in the leaf litter weight and a 60% decrease in the cesium concentration. Moreover, we also measured the amount of cesium washout. The cesium budget of experiment 1 showed no cesium gasification (wet oxidation avoids airborne cesium as this element is prone to be volatile at 600 °C), and that high sodium hypochlorite concentration and high temperature had a strong positive effect on leaf litter volume reduction and cesium decontamination. Experiment 2 confirmed the reproducibility of these results in leaves with different cesium concentration and harvested in different conditions. We could also explain the mechanism behind leaf litter weight and cesium concentration reduction. Experiment 3 helped us to investigate the effects of the matter present on the surface of the water and the contribution of water soluble cesium. Concurrent experiments on changes in leaf litter chemical composition confirmed that our modified wet oxidation method had an effect on the removal of acid-insoluble lignin. Removal of lignin, a refractory component, might allow for a better utilization of the residue left after implementation of the proposed simplified wet oxidation. Thus, real wastes could be smaller than the residues. Together with the observed smaller cesium concentration in the residue, the proposed method in this study is expected to contribute to mitigate the risk due to the fallen leaves containing cesium. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cesium-specific phenolic ion exchange resin

DOEpatents

Bibler, J.P.; Wallace, R.M.

1995-08-15

A phenolic, cesium-specific, cation exchange resin is prepared by neutralizing resorcinol with potassium hydroxide, condensing/polymerizing the resulting intermediate with formaldehyde, heat-curing the resulting polymer to effect cross-linking and grinding it to desired particle size for use. This resin will selectively and efficiently adsorb cesium ions in the presence of a high concentration of sodium ions with a low carbon to cesium ratio. 2 figs.

Cesium-specific phenolic ion exchange resin

DOEpatents

Bibler, Jane P.; Wallace, Richard M.

1995-01-01

A phenolic, cesium-specific, cation exchange resin is prepared by neutralizing resorcinol with potassium hydroxide, condensing/polymerizing the resulting intermediate with formaldehyde, heat-curing the resulting polymer to effect cross-linking and grinding it to desired particle size for use. This resin will selectively and efficiently adsorb cesium ions in the presence of a high concentration of sodium ions with a low carbon to cesium ratio.

Stable and radioactive cesium: A review about distribution in the environment, uptake and translocation in plants, plant reactions and plants' potential for bioremediation.

PubMed

Burger, Anna; Lichtscheidl, Irene

2018-03-15

Radiocesium in water, soil, and air represents a severe threat to human health and the environment. It either acts directly on living organisms from external sources, or it becomes incorporated through the food chain, or both. Plants are at the base of the food chain; it is therefore essential to understand the mechanisms of plants for cesium retention and uptake. In this review we summarize investigations about sources of stable and radioactive cesium in the environment and harmful effects caused by internal and external exposure of plants to radiocesium. Uptake of cesium into cells occurs through molecular mechanisms such as potassium and calcium transporters in the plasma membrane. In soil, bioavailability of cesium depends on the chemical composition of the soil and physical factors such as pH, temperature and tilling as well as on environmental factors such as soil microorganisms. Uptake of cesium occurs also from air through interception and absorption on leaves and from water through the whole submerged surface. We reviewed information about reducing cesium in the vegetation by loss processes, and we extracted transfer factors from the available literature and give an overview over the uptake capacities of 72 plants for cesium from the substratum to the biomass. Plants with high uptake potential could be used to remediate soil and water from radiocesium by accumulation and rhizofiltration. Inside plants, cesium distributes fast between the different plant organs and cells, but cesium in soil is extremely stable and remains for decades in the rhizosphere. Monitoring of contaminated soil therefore has to continue for many decades, and edible plants grown on such soil must continuously be monitored. Copyright © 2017 Elsevier B.V. All rights reserved.

Forcing Cesium into Higher Oxidation States Using Useful hard x-ray Induced Chemistry under High Pressure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sneed, D.; Pravica, M.; Kim, E.

This paper discusses our attempt to synthesize higher oxidation forms of cesium fluoride by pressurizing cesium fluoride in a fluorine-rich environment created via the x-ray decomposition of potassium tetrafluoroborate. This was done in order to confirm recent theoretical predictions of higher oxidation forms of CsFn. We discuss the development of a technique to produce molecular fluorine in situ via useful hard x-ray photochemistry, and the attempt to utilize this technique to form higher oxidation states of cesium fluoride. In order to verify the formation of the novel stoichiometric species of CsFn. X-ray Absorption Near Edge Spectroscopy (XANES) centered on themore » cesium K-edge was performed to probe the oxidation state of cesium as well as the local molecular coordination around Cs.« less

Effects of Cesium Cations in Lithium Deposition via Self-Healing Electrostatic Shield Mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ding, Fei; Xu, Wu; Chen, Xilin

Lithium (Li) dendrite formation is one of the critical challenges for rechargeable Li metal batteries. The traditional method to suppress Li dendrites by using high-quality solid electrolyte interface (SEI) films cannot effectively solve this problem. Recently, we proposed a novel self-healing electrostatic shield (SHES) mechanism to change the Li deposition behavior. The SHES mechanism forces Li to be deposited in the region away from protuberant tips by using non-Li cations as additives that preferentially accumulate but not deposit on the active sites of Li electrode. In this paper, the electrochemical behavior of cesium cation (Cs+) as the typical non-Li cationmore » suitable for the SHES mechanism was further investigated in detail to reveal its effects on preventing Li dendrites and interactions with Li electrode. It is found that typical adsorption behavior instead of chemical reaction is observed. The existence of Cs+ cation in the electrolyte does not change the components and structure of the Li surface film and this is consistent with the projection of the SHES mechanism. Various factors affecting the effectiveness of SHES mechanism are also discussed. The morphologies of Li films deposited is smooth and uniform during the repeated deposition-stripping cycles and at various current densities (from 0.1 to 1.0 mA cm-2) by adding just a small amount (0.05 M) of Cs+-additive in the electrolyte.« less

Cesium migration in saturated silica sand and Hanford sediments as impacted by ionic strength.

PubMed

Flury, Markus; Czigány, Szabolcs; Chen, Gang; Harsh, James B

2004-07-01

Large amounts of 137Cs have been accidentally released to the subsurface from the Hanford nuclear site in the state of Washington, USA. The cesium-containing liquids varied in ionic strengths, and often had high electrolyte contents, mainly in the form of NaNO3 and NaOH, reaching concentrations up to several moles per liter. In this study, we investigated the effect of ionic strengths on Cs migration through two types of porous media: silica sand and Hanford sediments. Cesium sorption and transport was studied in 1, 10, 100, and 1000 mM NaCl electrolyte solutions at pH 10. Sorption isotherms were constructed from batch equilibrium experiments and the batch-derived sorption parameters were compared with column breakthrough curves. Column transport experiments were analyzed with a two-site equilibrium-nonequilibrium model. Cesium sorption to the silica sand in batch experiments showed a linear sorption isotherm for all ionic strengths, which matched well with the results from the column experiments at 100 and 1000 mM ionic strength; however, the column experiments at 1 and 10 mM ionic strength indicated a nonlinear sorption behavior of Cs to the silica sand. Transport through silica sand occurred under one-site sorption and equilibrium conditions. Cesium sorption to Hanford sediments in both batch and column experiments was best described with a nonlinear Freundlich isotherm. The column experiments indicated that Cs transport in Hanford sediments occurred under two-site equilibrium and nonequilibrium sorption. The effect of ionic strength on Cs transport was much more pronounced in Hanford sediments than in silica sands. Effective retardation factors of Cs during transport through Hanford sediments were reduced by a factor of 10 when the ionic strength increased from 100 to 1000 mM; for silica sand, the effective retardation was reduced by a factor of 10 when ionic strength increased from 1 to 1000 mM. A two order of magnitude change in ionic strength was needed in the silica sand to observe the same change in Cs retardation as in Hanford sediments. Copyright 2003 Elsevier B.V.

Simulation of cesium injection and distribution in rf-driven ion sources for negative hydrogen ion generation.

PubMed

Gutser, R; Fantz, U; Wünderlich, D

2010-02-01

Cesium seeded sources for surface generated negative hydrogen ions are major components of neutral beam injection systems in future large-scale fusion experiments such as ITER. Stability and delivered current density depend highly on the cesium conditions during plasma-on and plasma-off phases of the ion source. The Monte Carlo code CSFLOW3D was used to study the transport of neutral and ionic cesium in both phases. Homogeneous and intense flows were obtained from two cesium sources in the expansion region of the ion source and from a dispenser array, which is located 10 cm in front of the converter surface.

Investigations of negative and positive cesium ion species

NASA Technical Reports Server (NTRS)

Chanin, L. M.

1978-01-01

A direct test is provided of the hypothesis of negative ion creation at the anode or collector of a diode operating under conditions simulating a cesium thermionic converter. The experimental technique involves using direct ion sampling through the collector electrode with mass analysis using a quadrupole mass analyzer. Similar measurements are undertaken on positive ions extracted through the emitter electrode. Measurements were made on a variety of gases including pure cesium, helium-cesium mixtures and cesium-hydrogen as well as cesium-xenon mixtures. The gas additive was used primarily to aid in understanding the negative ion formation processes. Measurements were conducted using emitter (cathode) temperatures up to about 1000 F. The major negative ion identified through the collector was Cs(-) with minor negative ion peaks tentatively identified as H(-), H2(-), H3(-), He(-) and a mass 66. Positive ions detected were believed to be Cs(+), Cs2(+) and Cs3(+).

Characterization of home-made silver sulphide based iodide selective electrode.

PubMed

Rajbhandari Nyachhyon, A; Yadav, A P; Manandhar, K; Pradhananga, R R

2010-09-15

Polycrystalline silver sulphide/silver iodide ion selective electrodes (ISEs) with four different compositions, 9:1, 2:1, 1:1, 1:9 Ag(2)S-AgI mole ratios, have been fabricated in the laboratory and characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). X-ray diffraction studies show the presence of Ag(3)SI, Ag(2)S and AgI crystalline phases in the electrode material. The electrode surfaces have been found to become smoother and lustrous with increasing percentage of silver sulphide in silver iodide. ISE 1:1, ISE 2:1 and ISE 9:1 all responded in Nernstian manner with slopes of about 60 mV/decade change in iodide ion concentration in the linear range of 1 x 10(-1) to 1 x 10(-6)M while ISE 1:9 showed sub-Nernstian behavior with slope of about 45 mV up to the concentration 1 x 10(-5)M. Two capacitive loops, one corresponding to the charge transfer process at metal electrode and the back contact and a second loop corresponding to the charge transfer process at membrane-electrolyte interface have been observed at high and low frequency ranges, respectively. Mott-Schottky analysis shows that the materials are n-type semiconductors with donor defect concentrations in the range of 5.1 x 10(14) to 2.4 x 10(19)/cm(3). Copyright (c) 2010 Elsevier B.V. All rights reserved.

Presence and partitioning behavior of polyfluorinated iodine alkanes in environmental matrices around a fluorochemical manufacturing plant: another possible source for perfluorinated carboxylic acids?

PubMed

Ruan, Ting; Wang, Yawei; Wang, Thanh; Zhang, Qinghua; Ding, Lei; Liu, Jiyan; Wang, Chang; Qu, Guangbo; Jiang, Guibin

2010-08-01

The indistinct origins of some ubiquitous perfluorinated alkyl acids have attracted great attention in recent decades. In this present work, even-chained polyfluorinated iodides (PFIs), a group of volatile perfluorinated compounds (PFCs), including four perfluorinated iodine alkanes (FIAs) and three polyfluorinated telomer iodides (FTIs) were confirmed to be present in the environment. A wide concentration range was found for FIAs at 1.41 to 3.08x10(4) pg/L, and for FTIs at 1.39 to 1.32x10(3) pg/L in the ambient air collected around a fluorochemical manufacturing plant in Shandong province, northern China. Whereas for surface soils, most of these PFIs were below detection limits and only small amounts of analytes with higher carbon chain (such as perfluorododecyl iodide and 1H,1H,2H,2H-perfluorodecyl iodide, 16.6-499 pg/g) could be sporadically detected. The presence of the PFIs in different environmental matrices in the investigated area and calculated vapor pressures (0.095-20.4 Torr) verify that they can be considered as volatile organic chemicals and easily be released into the atmosphere. Together with reported degradation ability and long-range transport potential, the identification of these PFIs indicates that unintentional release during the telomer reaction process might also be another route for the formation and distribution of certain polyfluorinated alcohols, aldehydes, and carboxylic acid derivatives under oxidative conditions in the environment.

21 CFR 520.763a - Dithiazanine iodide tablets.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dithiazanine iodide tablets. 520.763a Section 520... iodide tablets. (a) Chemical name. 3-Ethyl-2-[5-(3-ethyl - 2 - benzothiazolinylidene) - 1,3 - pentadienyl]-benzothiazolium iodide. (b) Specifications. Dithiazanine iodide tablets contain 10 milligrams, 50 milligrams, 100...

21 CFR 172.375 - Potassium iodide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Potassium iodide. 172.375 Section 172.375 Food and... Dietary and Nutritional Additives § 172.375 Potassium iodide. The food additive potassium iodide may be safely used in accordance with the following prescribed conditions: (a) Potassium iodide may be safely...

Evaluation of physicochemical properties of radioactive cesium in municipal solid waste incineration fly ash by particle size classification and leaching tests.

PubMed

Fujii, Kengo; Ochi, Kotaro; Ohbuchi, Atsushi; Koike, Yuya

2018-07-01

After the Fukushima Daiichi-Nuclear Power Plant accident, environmental recovery was a major issue because a considerable amount of municipal solid waste incineration (MSWI) fly ash was highly contaminated with radioactive cesium. To the best of our knowledge, only a few studies have evaluated the detailed physicochemical properties of radioactive cesium in MSWI fly ash to propose an effective method for the solidification and reuse of MSWI fly ash. In this study, MSWI fly ash was sampled in Fukushima Prefecture. The physicochemical properties of radioactive cesium in MSWI fly ash were evaluated by particle size classification (less than 25, 25-45, 45-100, 100-300, 300-500, and greater than 500 μm) and the Japanese leaching test No. 13 called "JLT-13". These results obtained from the classification of fly ash indicated that the activity concentration of radioactive cesium and the content of the coexisting matter (i.e., chloride and potassium) temporarily change in response to the particle size of fly ash. X-ray diffraction results indicated that water-soluble radioactive cesium exists as CsCl because of the cooling process and that insoluble cesium is bound to the inner sphere of amorphous matter. These results indicated that the distribution of radioactive cesium depends on the characteristics of MSWI fly ash. Copyright © 2018 Elsevier Ltd. All rights reserved.

Calix[4]pyrrole: A New Ion-Pair Receptor As Demonstrated by Liquid-Liquid Extraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wintergerst, Mr. Matthieu; Levitskaia, Tatiana G.; Moyer, Bruce A

Solvent-extraction studies provide confirming evidence that meso-octamethylcalix[4]pyrrole acts as an ion-pair receptor for cesium chloride and cesium bromide in nitrobenzene solution. The stoichiometry of the interaction under extraction conditions from water to nitrobenzene was determined from plots of the cesium distribution ratios vs cesium salt and receptor concentration, indicating the formation of an ionpaired 1:1:1 cesium:calix[4]pyrrole:halide complex. The extraction results were modeled to evaluate the equilibria inherent to the solvent-extraction system, with either chloride or bromide. The binding energy between the halide anion and the calix[4]pyrrole was found to be about 7 kJ/mol larger for cesium chloride than for themore » cesium bromide. The ion-pairing free energies between the calix[4]pyrrole-halide complex and the cesium cation are nearly the same within experimental uncertainty for either halide, consistent with a structural model in which the Cs+ cation resides in the calix bowl. These results are unexpected since nitrobenzene is a polar solvent that generally leads to dissociated complexes in the organic phase when used as a diluent in extraction studies of univalent ions. Control studies involving nitrate revealed no evidence of ion pairing for CsNO3 under conditions identical to those where it is observed for CsCl and CsBr.« less

Calix[4]pyrrole: A New Ion-Pair Receptor As Demonstrated by Liquid-Liquid Extraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wintergerst, Mr. Matthieu; Levitskaia, Tatiana G.; Moyer, Bruce A

Solvent extraction studies provide confirming evidence that meso-octamethylcalix[4]pyrrole acts as an ion-pair receptor for cesium chloride and cesium bromide in nitrobenzene solution. The stoichiometry of the interaction under extraction conditions from water to nitrobenzene was determined from plots of the cesium distribution ratios vs. cesium salt and receptor concentration, indicating the formation of an ion-paired 1:1:1 cesium:calix[4]pyrrole:halide complex. The extraction results were modeled to evaluate the equilibria inherent to the solvent extraction system, either with chloride or bromide. The binding energy between the halide anion and the calix[4]pyrrole was found to be about 7 kJ/mol larger for cesium chloride thanmore » for the cesium bromide. The ion-pairing free energies between the calix[4]pyrrole-halide complex and the cesium cation are nearly the same within experimental uncertainty for either halide, consistent with a structural model in which the Cs+ cation resides in the calix bowl. These results are unexpected since nitrobenzene is a very polar solvent that generally leads to dissociated complexes in the organic phase when used as a diluent in extraction studies of univalent ions. Control studies involving nitrate revealed no evidence of ion-pairing for CsNO3 under conditions identical to those where it is observed for CsCl and CsBr.« less

Fukushima- Ocean Impacts and Public Concerns

NASA Astrophysics Data System (ADS)

Buesseler, K.

2015-12-01

The triple disaster of the March 11, 2011 earthquake, tsunami, and subsequent radiation releases at Fukushima Dai-ichi were unprecedented events for the ocean and society. This presentation will provide an overview of studies of Fukushima radionuclides in the ocean. The radioactive releases from Fukushima will be compared to natural and prior human sources. The fate of cesium is largely determined by its soluble nature in seawater, though uptake in sediments does occur via cesium's association with both detrital particles and biological uptake and sedimentation. Cesium's continued supply from the rivers and ongoing leakages at the nuclear power plants suggests that coastal sediments may remain contaminated for decades to come. Although levels of cesium in the ocean and being released from Fukushima more than four years later are orders of magnitude lower than in 2011, other isotopes such as strontium-90 remain of interest as they are elevated relative to cesium in the groundwater and storage tanks at the reactor site. Across the Pacific, Fukushima cesium is starting to be detectable along the west coast of North America. Although models suggest cesium will be at levels well below those considered of human health concern, the public is worried about the lack of ocean monitoring of Fukushima radionuclides. We addressed these public concerns by creating "Our Radioactive Ocean" a citizen-scientist crowd-funded campaign that provides a sampling kit that can use to sample their favorite beach. Once collected, samples are returned to WHOI for analyses of the isotopes of cesium that allow us to distinguish Fukushima cesium from other sources (http://OurRadioactiveOcean.org ). However to measure the low levels of cesium already in the ocean 20 liter samples are needed. To increase public participation, we will also present results from a new wearable sample collector, the "RadBand" which contains a small amount of cesium selective resin that surfers and swimmers can wear on their ankle. A prototype RadBand is being tested as part of The Longest Swim, an attempt by Ben Lecomte to swim from Tokyo to San Francisco (http://thelongestswim.com/ ). This swim is being used as another way to engage the public on ocean and environmental issues.

Separation technique provides rapid quantitative determination of cesium-137 in irradiated nuclear fuel

NASA Technical Reports Server (NTRS)

Ellenburg, E. J.; Mc Cown, J. J.

1967-01-01

Potassium cobalt ferrocyanide is used to determine cesium-137 activity in irradiated fuel samples. It preferentially removes cesium from an acid solution of the fuel material. The residue is filtered and analyzed with a gamma spectrometer.

Taming the Reactivity of Glycosyl Iodides To Achieve Stereoselective Glycosidation.

PubMed

Gervay-Hague, Jacquelyn

2016-01-19

Although glycosyl iodides have been known for more than 100 years, it was not until the 21st century that their full potential began to be harnessed for complex glycoconjugate synthesis. Mechanistic studies in the late 1990s probed glycosyl iodide formation by NMR spectroscopy and revealed important reactivity features embedded in protecting-group stereoelectronics. Differentially protected sugars having an anomeric acetate were reacted with trimethylsilyl iodide (TMSI) to generate the glycosyl iodides. In the absence of C-2 participation, generation of the glycosyl iodide proceeded by inversion of the starting anomeric acetate stereochemistry. Once formed, the glycosyl iodide readily underwent in situ anomerization, and in the presence of excess iodide, equilibrium concentrations of α- and β-iodides were established. Reactivity profiles depended upon the identity of the sugar and the protecting groups adorning it. Consistent with the modern idea of disarmed versus armed sugars, ester protecting groups diminished the reactivity of glycosyl iodides and ether protecting groups enhanced the reactivity. Thus, acetylated sugars were slower to form the iodide and anomerize than their benzylated analogues, and these disarmed glycosyl iodides could be isolated and purified, whereas armed ether-protected iodides could only be generated and reacted in situ. All other things being equal, the β-iodide was orders of magnitude more reactive than the thermodynamically more stable α-iodide, consistent with the idea of in situ anomerization introduced by Lemieux in the mid-20th century. Glycosyl iodides are far more reactive than the corresponding bromides, and with the increased reactivity comes increased stereocontrol, particularly when forming α-linked linear and branched oligosaccharides. Reactions with per-O-silylated glycosyl iodides are especially useful for the synthesis of α-linked glycoconjugates. Silyl ether protecting groups make the glycosyl iodide so reactive that even highly functionalized aglycon acceptors add. Following the coupling event, the TMS ethers are readily removed by methanolysis, and since all of the byproducts are volatile, multiple reactions can be performed in a single reaction vessel without isolation of intermediates. In this fashion, per-O-TMS monosaccharides can be converted to biologically relevant α-linked glycolipids in one pot. The stereochemical outcome of these reactions can also be switched to β-glycoside formation by addition of silver to chelate the iodide, thus favoring SN2 displacement of the α-iodide. While iodides derived from benzyl and silyl ether-protected oligosaccharides are susceptible to interglycosidic bond cleavage when treated with TMSI, the introduction of a single acetate protecting group prevents this unwanted side reaction. Partial acetylation of armed glycosyl iodides also attenuates HI elimination side reactions. Conversely, fully acetylated glycosyl iodides are deactivated and require metal catalysis in order for glycosidation to occur. Recent findings indicate that I2 activation of per-O-acetylated mono-, di-, and trisaccharides promotes glycosidation of cyclic ethers to give β-linked iodoalkyl glycoconjugates in one step. Products of these reactions have been converted into multivalent carbohydrate displays. With these synthetic pathways elucidated, chemical reactivity can be exquisitely controlled by the judicious selection of protecting groups to achieve high stereocontrol in step-economical processes.

Preliminary Evaluation of Cesium Distribution for Wet Sieving Process Planned for Soil Decontamination in Japan - 13104

DOE Office of Scientific and Technical Information (OSTI.GOV)

Enokida, Y.; Tanada, Y.; Hirabayashi, D.

2013-07-01

For the purpose of decontaminating radioactive cesium from a huge amount of soil, which has been estimated to be 1.2x10{sup 8} m{sup 3} by excavating to a 5-cm depth from the surface of Fukushima Prefecture where a severe nuclear accident occurred at TEPCO's power generating site and has emitted a significant amount of radioactive materials, mainly radioactive cesium, a wet sieving process was selected as one of effective methods available in Japan. Some private companies have demonstrated this process for soil treatment in the Fukushima area by testing at their plants. The results were very promising, and a full-fledged applicationmore » is expected to follow. In the present study, we spiked several aqueous samples containing soil collected from an industrial wet sieving plant located near our university for the recycling of construction wastes with non-radioactive cesium hydroxide. The present study provides scientific data concerning the effectiveness in volume reduction of the contaminated soil by a wet sieving process as well as the cesium distribution between the liquid phase and clay minerals for each sub-process of the full-scale one, but a simulating plant equipped with a process of coagulating sedimentation and operational safety fundamentals for the plant. Especially for the latter aspect, the study showed that clay minerals of submicron size strongly bind a high content of cesium, which was only slightly removed by coagulation with natural sedimentation (1 G) nor centrifugal sedimentation (3,700 G) and some of the cesium may be transferred to the effluent or recycled water. By applying ultracentrifugation (257,000 G), most of submicron clay minerals containing cesium was removed, and the cesium amount which might be transferred to the effluent or recycled water, could be reduced to less than 2.3 % of the original design by the addition of a cesium barrier consisting of ultracentrifugation or a hollow fiber membrane. (authors)« less

Distribution of radioactive cesium ((134)Cs Plus(137)Cs) in a contaminated Japanese soybean cultivar during the preparation of tofu, natto, and nimame (Boiled Soybean).

PubMed

Hachinohe, Mayumi; Kimura, Keitarou; Kubo, Yuji; Tanji, Katsuo; Hamamatsu, Shioka; Hagiwara, Shoji; Nei, Daisuke; Kameya, Hiromi; Nakagawa, Rikio; Matsukura, Ushio; Todoriki, Setsuko; Kawamoto, Shinichi

2013-06-01

We investigated the fate of radioactive cesium ((134)Cs plus (137)Cs) during the production of tofu, natto, and nimame (boiled soybean) from a contaminated Japanese soybean cultivar harvested in FY2011. Tofu, natto, and nimame were made from soybean grains containing radioactive cesium (240 to 340 Bq/kg [dry weight]), and the radioactive cesium in the processed soybean foods and in by-product fractions such as okara, broth, and waste water was measured with a germanium semiconductor detector. The processing factor is the ratio of radioactive cesium concentration of a product before and after processing. For tofu, natto, nimame, and for the by-product okara, processing factors were 0.12, 0.40, 0.20, and 0.18, respectively; this suggested that these three soybean foods and okara, used mainly as an animal feed, can be considered safe for human and animal consumption according to the standard limit for radioactive cesium of soybean grains. Furthermore, the ratio of radioactive cesium concentrations in the cotyledon, hypocotyl, and seed coat portions of the soybean grain was found to be approximately 1:1:0.4.

Negative ion production in large volume source with small deposition of cesium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacquot, C.; Pamela, J.; Riz, D.

1996-03-01

Experimental data on the enhancement of D{sup {minus}} (H{sup {minus}}) negative ion production due to cesium injection into a large volume multiampere negative ion source (MANTIS) are described. The directed deposition of small cesium amounts (5{endash}100 mg) from a compact, movable oven, placed into the central part of a MANTIS gas-discharge box was used. A calorimetrically measured D{sup {minus}} beam with an intensity up to 1.6 A and an extracted current density up to 4.2 mA/cm{sup 2} (beam energy 25 kV) was obtained. Exactly 30 mg of cesium provides at least one month of source operation (1000 pulses with amore » discharge pulse duration of 4 s). The effect of cesium on NI enhancement was immediately displayed after the distributed Cs deposition, but it needed some {open_quote}{open_quote}conditioning{close_quote}{close_quote} of cesium by tens of discharge pulses (or by several hours {open_quote}{open_quote}pause{close_quote}{close_quote}) in the case of a localized Cs deposition. No degradation of extraction-acceleration voltage holding on within the tested range of cesium injection was observed. {copyright} {ital 1996 American Institute of Physics.}« less

High voltage holding in the negative ion sources with cesium deposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belchenko, Yu.; Abdrashitov, G.; Ivanov, A.

High voltage holding of the large surface-plasma negative ion source with cesium deposition was studied. It was found that heating of ion-optical system electrodes to temperature >100 °C facilitates the source conditioning by high voltage pulses in vacuum and by beam shots. The procedure of electrode conditioning and the data on high-voltage holding in the negative ion source with small cesium seed are described. The mechanism of high voltage holding improvement by depletion of cesium coverage is discussed.

Behavior of cesium and thallium cations inside a calixarene cavity as probed by nuclear spin relaxation. Evidence of cation-pi interactions in water.

PubMed

Cuc, Diana; Bouguet-Bonnet, Sabine; Morel-Desrosiers, Nicole; Morel, Jean-Pierre; Mutzenhardt, Pierre; Canet, Daniel

2009-08-06

We have studied the complexes formed between the p-sulfonatocalix[4]arene and cesium or thallium metal cation, first by carbon-13 longitudinal relaxation of the calixarene molecule at two values of the magnetic field B(0). From the longitudinal relaxation times of an aromatic carbon directly bonded to a proton, thus subjected essentially to the dipolar interaction with that proton, we could obtain the correlation time describing the reorientation of the CH bond. The rest of this study has demonstrated that it is also the correlation time describing the tumbling of the whole calixarene assembly. From three non-proton-bearing carbons of the aromatic cycles (thus subjected to the chemical shift anisotropy and dipolar mechanisms), we have been able to determine the variation of the chemical shift anisotropy when going from the free to the complex form of the calixarene. These variations not only provide the location of the cation inside the calixarene cavity but also constitute a direct experimental proof of the cation-pi interactions. These results are complemented by cesium and thallium relaxation measurements performed again at two values of the magnetic field B(0). An estimation of the mean distance between the cation and the calixarene protons could be obtained. These measurements have also revealed an important chemical shift anisotropy of thallium upon complexation.

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

PubMed

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.

[Reduction of radioactive cesium content in pond smelt by cooking].

PubMed

Nabeshi, Hiromi; Tsutsumi, Tomoaki; Hachisuka, Akiko; Matsuda, Rieko

2013-01-01

In Japan, seafood may be eaten raw or after having been cooked in diverse ways. Therefore, it is important to understand the effect of cooking on the extent of contamination with radioactive materials in order to avoid internal exposure to radioactive materials via seafood. In this study, we investigated the changes in radioactive cesium content in pond smelt cooked in four different ways: grilled, stewed (kanroni), fried and soaked (nanbanzuke). The radioactive cesium content in grilled, kanroni and fried pond smelt was almost unchanged compared with the uncooked state. In contrast, radioactive cesium content in nanbanzuke pond smelt was decreased by about 30%. Our result suggests that soaking cooked pond smelt in seasoning is an effective method of reducing the burden radioactive cesium.

Low-energy vibrational dynamics of cesium borate glasses.

PubMed

Crupi, C; D'Angelo, G; Vasi, C

2012-06-07

Low-temperature specific heat and inelastic light scattering experiments have been performed on a series of cesium borate glasses and on a cesium borate crystal. Raman measurements on the crystalline sample have revealed the existence of cesium rattling modes in the same frequency region where glasses exhibit the boson peak (BP). These localized modes are supposed to overlap with the BP in cesium borate glasses affecting its magnitude. Their influence on the low frequency vibrational dynamics in glassy samples has been considered, and their contribution to the specific heat has been estimated. Evidence for a relation between the changes of the BP induced by the increased amount of metallic oxide and the variations of the elastic medium has been provided.

Hybrid micro-particles as a magnetically-guidable decontaminant for cesium-eluted ash slurry

NASA Astrophysics Data System (ADS)

Namiki, Yoshihisa; Ueyama, Toshihiko; Yoshida, Takayuki; Watanabe, Ryoei; Koido, Shigeo; Namiki, Tamami

2014-09-01

Decontamination of the radioactive cesium that is widely dispersed owing to a nuclear power station accident and concentrated in fly ash requires an effective elimination system. Radioactive fly ash contains large amounts of water-soluble cesium that can cause severe secondary contamination and represents a serious health risk, yet its complete removal is complicated and difficult. Here it is shown that a new fine-powder formulation can be magnetically guided to eliminate cesium after being mixed with the ash slurry. This formulation, termed MagCE, consists of a ferromagnetic porous structure and alkaline- and salt-resistant nickel ferrocyanide. It has potent cesium-adsorption- and magnetic-separation-properties. Because of its resistance against physical and chemical attack such as with ash particles, as well as with the high pH and salt concentration of the ash slurry, MagCE simplifies the decontamination process without the need of the continued presence of the hazardous water-soluble cesium in the treated ash.

The effect of cesium carbonate on 1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C{sub 61} aggregation in films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lindemann, William R.; Wang, Wenjie; Shinar, Joseph

2014-11-10

Surface-pressure versus molecular area isotherms, X-ray reflectivity, and X-ray near-total reflection fluorescence were used to study the properties of 1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C{sub 61} (PCBM) that was pre-mixed with cesium carbonate and spread as a film at the air-water interface. The pre-mixed PCBM with cesium carbonate demonstrated a strikingly strong effect on the organization of the film. Whereas films formed from pure PCBM solution were rough due to strong inter-molecular interactions, the films formed from the mixture were much smoother. This indicates that the cesium carbonate moderates the inter-molecular interactions among PCBM molecules, hinting that the cesium diffusion observed in inverted organic photovoltaicmore » structures and the likely ensuing ionic Cs-PCBM interaction decrease aggregation tendency of PCBM. This implies that the use of cesium salts affects the morphology of the organic layer and consequently improves the efficiency of these devices.« less

The effect of cesium carbonate on 1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C 61 aggregation in films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lindemann, William R.; Wang, Wenjie; Fungura, Fadzai

2014-11-11

Surface-pressure isotherms, X-ray reflectivity, and X-ray near-total reflection fluorescence were used to study the properties of 1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C 61 (PCBM) that was pre-mixed with cesium carbonate and spread as a film at the air-water interface. The pre-mixed PCBM with cesium carbonate demonstrated a strikingly strong effect on the organization of the film. Whereas films formed from pure PCBM solution were rough due to strong inter-molecular interactions, the films formed from the mixture were much smoother. This indicates that the cesium carbonate moderates the inter-molecular interactions among PCBM molecules, hinting that the cesium diffusion observed in inverted organic photovoltaics and the likelymore » ensuing ionic Cs-PCBM interaction decrease aggregation tendency of PCBM. As a result, this implies that the use of cesium salts affects the morphology of the organic layer and consequently improves the efficiency of these devices.« less

Hybrid micro-particles as a magnetically-guidable decontaminant for cesium-eluted ash slurry

PubMed Central

Namiki, Yoshihisa; Ueyama, Toshihiko; Yoshida, Takayuki; Watanabe, Ryoei; Koido, Shigeo; Namiki, Tamami

2014-01-01

Decontamination of the radioactive cesium that is widely dispersed owing to a nuclear power station accident and concentrated in fly ash requires an effective elimination system. Radioactive fly ash contains large amounts of water-soluble cesium that can cause severe secondary contamination and represents a serious health risk, yet its complete removal is complicated and difficult. Here it is shown that a new fine-powder formulation can be magnetically guided to eliminate cesium after being mixed with the ash slurry. This formulation, termed MagCE, consists of a ferromagnetic porous structure and alkaline- and salt-resistant nickel ferrocyanide. It has potent cesium-adsorption- and magnetic-separation-properties. Because of its resistance against physical and chemical attack such as with ash particles, as well as with the high pH and salt concentration of the ash slurry, MagCE simplifies the decontamination process without the need of the continued presence of the hazardous water-soluble cesium in the treated ash. PMID:25192495

Hybrid micro-particles as a magnetically-guidable decontaminant for cesium-eluted ash slurry.

PubMed

Namiki, Yoshihisa; Ueyama, Toshihiko; Yoshida, Takayuki; Watanabe, Ryoei; Koido, Shigeo; Namiki, Tamami

2014-09-05

Decontamination of the radioactive cesium that is widely dispersed owing to a nuclear power station accident and concentrated in fly ash requires an effective elimination system. Radioactive fly ash contains large amounts of water-soluble cesium that can cause severe secondary contamination and represents a serious health risk, yet its complete removal is complicated and difficult. Here it is shown that a new fine-powder formulation can be magnetically guided to eliminate cesium after being mixed with the ash slurry. This formulation, termed MagCE, consists of a ferromagnetic porous structure and alkaline- and salt-resistant nickel ferrocyanide. It has potent cesium-adsorption- and magnetic-separation-properties. Because of its resistance against physical and chemical attack such as with ash particles, as well as with the high pH and salt concentration of the ash slurry, MagCE simplifies the decontamination process without the need of the continued presence of the hazardous water-soluble cesium in the treated ash.

Effect of the cesium and potassium doping of multiwalled carbon nanotubes grown in an electrical arc on their emission characteristics

NASA Astrophysics Data System (ADS)

Izrael'yants, K. R.; Orlov, A. P.; Ormont, A. B.; Chirkova, E. G.

2017-04-01

The effect of cesium and potassium atoms deposited onto multiwalled carbon nanotubes grown in an electrical arc on their emission characteristics was studied. The current-voltage characteristics of the field electron emission of specimens with cesium or potassium doped multiwalled carbon nanotubes of this type were revealed to retain their linear character in the Fowler-Nordheim coordinates within several orders of magnitude of change in the emission current. The deposition of cesium and potassium atoms was shown to lead to a considerable increase in the emission current and a decrease in the work function φ of studied emitters with multiwalled nanotubes. The work function was established to decrease to φ 3.1 eV at an optimal thickness of coating with cesium atoms and to φ 2.9 eV in the case of doping with potassium atoms. Cesium and potassium deposition conditions optimal for the attainment of a maximum emission current were found.

Adsorption of cesium on cement mortar from aqueous solutions.

PubMed

Volchek, Konstantin; Miah, Muhammed Yusuf; Kuang, Wenxing; DeMaleki, Zack; Tezel, F Handan

2011-10-30

The adsorption of cesium on cement mortar from aqueous solutions was studied in series of bench-scale tests. The effects of cesium concentration, temperature and contact time on process kinetics and equilibrium were evaluated. Experiments were carried out in a range of initial cesium concentrations from 0.0103 to 10.88 mg L(-1) and temperatures from 278 to 313 K using coupons of cement mortar immersed in the solutions. Non-radioactive cesium chloride was used as a surrogate of the radioactive (137)Cs. Solution samples were taken after set periods of time and analyzed by inductively coupled plasma mass spectroscopy. Depending on the initial cesium concentration, its equilibrium concentration in solution ranged from 0.0069 to 8.837 mg L(-1) while the respective surface concentration on coupons varied from 0.0395 to 22.34 μg cm(-2). Equilibrium test results correlated well with the Freundlich isotherm model for the entire test duration. Test results revealed that an increase in temperature resulted in an increase in adsorption rate and a decrease in equilibrium cesium surface concentration. Among several kinetic models considered, the pseudo-second order reaction model was found to be the best to describe the kinetic test results in the studied range of concentrations. The adsorption activation energy determined from Arrhenius equation was found to be approximately 55.9 kJ mol(-1) suggesting that chemisorption was the prevalent mechanism of interaction between cesium ions and cement mortar. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Dietary Iodine Sufficiency and Moderate Insufficiency in the Lactating Mother and Nursing Infant: A Computational Perspective

PubMed Central

Fisher, W.; Wang, Jian; George, Nysia I.; Gearhart, Jeffery M.; McLanahan, Eva D.

2016-01-01

The Institute of Medicine recommends that lactating women ingest 290 μg iodide/d and a nursing infant, less than two years of age, 110 μg/d. The World Health Organization, United Nations Children’s Fund, and International Council for the Control of Iodine Deficiency Disorders recommend population maternal and infant urinary iodide concentrations ≥ 100 μg/L to ensure iodide sufficiency. For breast milk, researchers have proposed an iodide concentration range of 150–180 μg/L indicates iodide sufficiency for the mother and infant, however no national or international guidelines exist for breast milk iodine concentration. For the first time, a lactating woman and nursing infant biologically based model, from delivery to 90 days postpartum, was constructed to predict maternal and infant urinary iodide concentration, breast milk iodide concentration, the amount of iodide transferred in breast milk to the nursing infant each day and maternal and infant serum thyroid hormone kinetics. The maternal and infant models each consisted of three sub-models, iodide, thyroxine (T4), and triiodothyronine (T3). Using our model to simulate a maternal intake of 290 μg iodide/d, the average daily amount of iodide ingested by the nursing infant, after 4 days of life, gradually increased from 50 to 101 μg/day over 90 days postpartum. The predicted average lactating mother and infant urinary iodide concentrations were both in excess of 100 μg/L and the predicted average breast milk iodide concentration, 157 μg/L. The predicted serum thyroid hormones (T4, free T4 (fT4), and T3) in both the nursing infant and lactating mother were indicative of euthyroidism. The model was calibrated using serum thyroid hormone concentrations for lactating women from the United States and was successful in predicting serum T4 and fT4 levels (within a factor of two) for lactating women in other countries. T3 levels were adequately predicted. Infant serum thyroid hormone levels were adequately predicted for most data. For moderate iodide deficient conditions, where dietary iodide intake may range from 50 to 150 μg/d for the lactating mother, the model satisfactorily described the iodide measurements, although with some variation, in urine and breast milk. Predictions of serum thyroid hormones in moderately iodide deficient lactating women (50 μg/d) and nursing infants did not closely agree with mean reported serum thyroid hormone levels, however, predictions were usually within a factor of two. Excellent agreement between prediction and observation was obtained for a recent moderate iodide deficiency study in lactating women. Measurements included iodide levels in urine of infant and mother, iodide in breast milk, and serum thyroid hormone levels in infant and mother. A maternal iodide intake of 50 μg/d resulted in a predicted 29–32% reduction in serum T4 and fT4 in nursing infants, however the reduced serum levels of T4 and fT4 were within most of the published reference intervals for infant. This biologically based model is an important first step at integrating the rapid changes that occur in the thyroid system of the nursing newborn in order to predict adverse outcomes from exposure to thyroid acting chemicals, drugs, radioactive materials or iodine deficiency. PMID:26930410

Dietary Iodine Sufficiency and Moderate Insufficiency in the Lactating Mother and Nursing Infant: A Computational Perspective.

PubMed

Fisher, W; Wang, Jian; George, Nysia I; Gearhart, Jeffery M; McLanahan, Eva D

2016-01-01

The Institute of Medicine recommends that lactating women ingest 290 μg iodide/d and a nursing infant, less than two years of age, 110 μg/d. The World Health Organization, United Nations Children's Fund, and International Council for the Control of Iodine Deficiency Disorders recommend population maternal and infant urinary iodide concentrations ≥ 100 μg/L to ensure iodide sufficiency. For breast milk, researchers have proposed an iodide concentration range of 150-180 μg/L indicates iodide sufficiency for the mother and infant, however no national or international guidelines exist for breast milk iodine concentration. For the first time, a lactating woman and nursing infant biologically based model, from delivery to 90 days postpartum, was constructed to predict maternal and infant urinary iodide concentration, breast milk iodide concentration, the amount of iodide transferred in breast milk to the nursing infant each day and maternal and infant serum thyroid hormone kinetics. The maternal and infant models each consisted of three sub-models, iodide, thyroxine (T4), and triiodothyronine (T3). Using our model to simulate a maternal intake of 290 μg iodide/d, the average daily amount of iodide ingested by the nursing infant, after 4 days of life, gradually increased from 50 to 101 μg/day over 90 days postpartum. The predicted average lactating mother and infant urinary iodide concentrations were both in excess of 100 μg/L and the predicted average breast milk iodide concentration, 157 μg/L. The predicted serum thyroid hormones (T4, free T4 (fT4), and T3) in both the nursing infant and lactating mother were indicative of euthyroidism. The model was calibrated using serum thyroid hormone concentrations for lactating women from the United States and was successful in predicting serum T4 and fT4 levels (within a factor of two) for lactating women in other countries. T3 levels were adequately predicted. Infant serum thyroid hormone levels were adequately predicted for most data. For moderate iodide deficient conditions, where dietary iodide intake may range from 50 to 150 μg/d for the lactating mother, the model satisfactorily described the iodide measurements, although with some variation, in urine and breast milk. Predictions of serum thyroid hormones in moderately iodide deficient lactating women (50 μg/d) and nursing infants did not closely agree with mean reported serum thyroid hormone levels, however, predictions were usually within a factor of two. Excellent agreement between prediction and observation was obtained for a recent moderate iodide deficiency study in lactating women. Measurements included iodide levels in urine of infant and mother, iodide in breast milk, and serum thyroid hormone levels in infant and mother. A maternal iodide intake of 50 μg/d resulted in a predicted 29-32% reduction in serum T4 and fT4 in nursing infants, however the reduced serum levels of T4 and fT4 were within most of the published reference intervals for infant. This biologically based model is an important first step at integrating the rapid changes that occur in the thyroid system of the nursing newborn in order to predict adverse outcomes from exposure to thyroid acting chemicals, drugs, radioactive materials or iodine deficiency.

Gel electrophoresis coupled to inductively coupled plasma-mass spectrometry using species-specific isotope dilution for iodide and iodate determination in aerosols.

PubMed

Brüchert, Wolfram; Helfrich, Andreas; Zinn, Nico; Klimach, Thomas; Breckheimer, Markus; Chen, Hongwei; Lai, Senchao; Hoffmann, Thorsten; Bettmer, Jörg

2007-02-15

In this paper, we present an online coupling of gel electrophoresis (GE) and inductively coupled plasma-mass spectrometry (ICP-MS) for the determination of iodine species (iodide and iodate) in liquid (seawater) and aerosol samples. For the first time, this approach is applied to the analysis of small molecules, and initial systematic investigations revealed that the migration behavior as well as the detection sensitivity strongly depends on the matrix (e.g., high concentrations of chloride). These effects could consequently affect the accuracy of analytical results, so that they need to be considered for the analysis of real samples. The technique used for quantification is species-specific isotope dilution analysis (ssIDA), which is a matrix-independent calibration method under certain conditions. We demonstrate that the use of 129I-enriched iodide and iodate allows the correction of the impact of the matrix on both, the electrophoretic migration and the detection sensitivity of the ICP-MS. After optimization, this coupling offers a novel and alternative method in the analysis of iodine compounds in various matrices. Here, we demonstrate the analytical capability of the technique for the chemical characterization of marine aerosols. The results show the presence of iodide and iodate at the ng m(-3) and sub-ng m(-3) level in the investigated aerosol samples, which were taken at the coastal research station in Mace Head, Ireland. These results are in good agreement with other recent studies, which demonstrated that the iodine chemistry in the marine atmosphere is only poorly understood. In addition to iodide and iodate, another iodine compound could be separated and detected in certain samples with high total iodine concentrations and was identified as elemental iodine, probably in form of triiodide, by peak matching. However, it may arise from an artifact during sample preparation.

On-ground calibration of AGILE-GRID with a photon beam: results and lessons for the future

NASA Astrophysics Data System (ADS)

Cattaneo, P. W.; Rappoldi, A.

2013-06-01

On the AGILE satellite, there is the Gamma Ray Imaging Detector (GRID) consisting of a Silicon Tracker (ST), a Cesium Iodide Mini-Calorimeter and an Anti-Coincidence system of plastic scintillator bars. The ST needs a calibration with a γ-ray beam to validate the simulation used to calculate the detector response versus the energy and the direction of the γ rays. A tagged γ-ray beam line was designed at the Beam Test Facility of the Laboratori Nazionali of Frascati, generated by an electron beam through bremsstrahlung in a position-sensitive target. The γ-ray energy is deduced by the difference with the post-bremsstrahlung electron energy [P. W. Cattaneo, et al., Characterization of a tagged γ-ray beam line at the daΦne beam test facility, Nucl. Instr. and Meth. A 674 (2012) 55-66; P. W. Cattaneo, et al., First results about on-ground calibration of the silicon tracker for the agile satellite, Nucl. Instr. and Meth. A 630(1) (2011) 251-257.]. The electron energy is measured by a spectrometer consisting of a dipole magnet and an array of position sensitive silicon strip detectors, the Photon Tagging System (PTS). In this paper the setup and the calibration of AGILE performed in 2005 are described.

A robust approach to measuring the detective quantum efficiency of radiographic detectors in a clinical setting

NASA Astrophysics Data System (ADS)

McDonald, Michael C.; Kim, H. K.; Henry, J. R.; Cunningham, I. A.

2012-03-01

The detective quantum efficiency (DQE) is widely accepted as a primary measure of x-ray detector performance in the scientific community. A standard method for measuring the DQE, based on IEC 62220-1, requires the system to have a linear response meaning that the detector output signals are proportional to the incident x-ray exposure. However, many systems have a non-linear response due to characteristics of the detector, or post processing of the detector signals, that cannot be disabled and may involve unknown algorithms considered proprietary by the manufacturer. For these reasons, the DQE has not been considered as a practical candidate for routine quality assurance testing in a clinical setting. In this article we described a method that can be used to measure the DQE of both linear and non-linear systems that employ only linear image processing algorithms. The method was validated on a Cesium Iodide based flat panel system that simultaneously stores a raw (linear) and processed (non-linear) image for each exposure. It was found that the resulting DQE was equivalent to a conventional standards-compliant DQE with measurement precision, and the gray-scale inversion and linear edge enhancement did not affect the DQE result. While not IEC 62220-1 compliant, it may be adequate for QA programs.

Distillation device supplies cesium vapor at constant pressure

NASA Technical Reports Server (NTRS)

Basiulis, A.; Shefsiek, P. K.

1968-01-01

Distillation apparatus in the form of a U tube supplies small amounts of pure cesium vapor at constant pressure to a thermionic converter. The upstream leg of the U tube is connected to a vacuum pump to withdraw noncondensable impurities, the bottom portion serves as a reservoir for the liquid cesium.

Precipitation-adsorption process for the decontamination of nuclear waste supernates

DOEpatents

Lee, Lien-Mow; Kilpatrick, Lester L.

1984-01-01

High-level nuclear waste supernate is decontaminated of cesium by precipitation of the cesium and potassium with sodium tetraphenyl boron. Simultaneously, strontium-90 is removed from the waste supernate sorption of insoluble sodium titanate. The waste solution is then filtered to separate the solution decontaminated of cesium and strontium.

Precipitation-adsorption process for the decontamination of nuclear waste supernates

DOEpatents

Lee, L.M.; Kilpatrick, L.L.

1982-05-19

High-level nuclear waste supernate is decontaminated of cesium by precipitation of the cesium and potassium with sodium tetraphenyl boron. Simultaneously, strontium-90 is removed from the waste supernate sorption of insoluble sodium titanate. The waste solution is then filtered to separate the solution decontaminated of cesium and strontium.

Recovery of cesium and palladium from nuclear reactor fuel processing waste

DOEpatents

Campbell, David O.

1976-01-01

A method of recovering cesium and palladium values from nuclear reactor fission product waste solution involves contacting the solution with a source of chloride ions and oxidizing palladium ions present in the solution to precipitate cesium and palladium as Cs.sub.2 PdCl.sub.6.

Historical Cost Curves for Hydrogen Masers and Cesium Beam Frequency and Timing Standards

NASA Technical Reports Server (NTRS)

Remer, D. S.; Moore, R. C.

1985-01-01

Historical cost curves were developed for hydrogen masers and cesium beam standards used for frequency and timing calibration in the Deep Space Network. These curves may be used to calculate the cost of future hydrogen masers or cesium beam standards in either future or current dollars. The cesium beam standards are decreasing in cost by about 2.3% per year since 1966, and hydrogen masers are decreasing by about 0.8% per year since 1978 relative to the National Aeronautics and Space Administration inflation index.

Method for removing cesium from a nuclear reactor coolant

DOEpatents

Colburn, Richard P.

1986-01-01

A method of and system for removing cesium from a liquid metal reactor coolant including a carbon packing trap in the primary coolant system for absorbing a major portion of the radioactive cesium from the coolant flowing therethrough at a reduced temperature. A regeneration subloop system having a secondary carbon packing trap is selectively connected to the primary system for isolating the main trap therefrom and connecting it to the regeneration system. Increasing the temperature of the sodium flowing through the primary trap diffuses a portion of the cesium

Removal of Cesium From Acidic Radioactive Tank Waste Using IONSIV IE-911 (CST)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mann, Nicholas Robert; Todd, Terry Allen

2004-10-01

IONSIV IE-911, or the engineered form of crystalline silicotitanate (CST), manufactured by UOP Molecular Sieves, has been evaluated for the removal of cesium from Idaho National Engineering and Environmental Laboratory (INEEL) acidic radioactive tank waste. A series of batch contacts and column tests were performed by using three separate batches of CST. Batch contacts were performed to evaluate the concentration effects of nitric acid, sodium, and potassium ions on cesium sorption. Additional batch tests were performed to determine if americium, mercury, and plutonium would sorb onto IONSIV IE-911. An equilibrium isotherm was generated by using a concentrated tank waste simulant.more » Column tests using a 1.5 cm 3 column and flow rates of 3, 5, 10, 20, and 30 bed volumes (BV)/hr were performed to elucidate dynamic cesium sorption capacities and sorption kinetics. Additional experiments investigated the effect of CST batch and pretreatment on cesium sorption. The thermal stability of IONSIV IE-911 was evaluated by performing thermal gravimetric analysis/differential thermal analysis. Overall, IONSIV IE-911 was shown to be effective for cesium sorption from complex, highly acidic solutions; however, sorbent stability in these solutions may have a deleterious effect on cesium sorption.« less

Synergistically strengthened 3D micro-scavenger cage adsorbent for selective removal of radioactive cesium

PubMed Central

Jang, Sung-Chan; Kang, Sung-Min; Haldorai, Yuvaraj; Giribabu, Krishnan; Lee, Go-Woon; Lee, Young-Chul; Hyun, Moon Seop; Han, Young-Kyu; Roh, Changhyun; Huh, Yun Suk

2016-01-01

A novel microporous three-dimensional pomegranate-like micro-scavenger cage (P-MSC) composite has been synthesized by immobilization of iron phyllosilicates clay onto a Prussian blue (PB)/alginate matrix and tested for the removal of radioactive cesium from aqueous solution. Experimental results show that the adsorption capacity increases with increasing the inactive cesium concentration from 1 ppm to 30 ppm, which may be attributed to greater number of adsorption sites and further increase in the inactive cesium concentration has no effect. The P-MSC composite exhibit maximum adsorption capacity of 108.06 mg of inactive cesium per gram of adsorbent. The adsorption isotherm is better fitted to the Freundlich model than the Langmuir model. In addition, kinetics studies show that the adsorption process is consistent with a pseudo second-order model. Furthermore, at equilibrium, the composite has an outstanding adsorption capacity of 99.24% for the radioactive cesium from aqueous solution. This may be ascribed to the fact that the AIP clay played a substantial role in protecting PB release from the P-MSC composite by cross-linking with alginate to improve the mechanical stability. Excellent adsorption capacity, easy separation, and good selectivity make the adsorbent suitable for the removal of radioactive cesium from seawater around nuclear plants and/or after nuclear accidents. PMID:27917913

Synergistically strengthened 3D micro-scavenger cage adsorbent for selective removal of radioactive cesium.

PubMed

Jang, Sung-Chan; Kang, Sung-Min; Haldorai, Yuvaraj; Giribabu, Krishnan; Lee, Go-Woon; Lee, Young-Chul; Hyun, Moon Seop; Han, Young-Kyu; Roh, Changhyun; Huh, Yun Suk

2016-12-05

A novel microporous three-dimensional pomegranate-like micro-scavenger cage (P-MSC) composite has been synthesized by immobilization of iron phyllosilicates clay onto a Prussian blue (PB)/alginate matrix and tested for the removal of radioactive cesium from aqueous solution. Experimental results show that the adsorption capacity increases with increasing the inactive cesium concentration from 1 ppm to 30 ppm, which may be attributed to greater number of adsorption sites and further increase in the inactive cesium concentration has no effect. The P-MSC composite exhibit maximum adsorption capacity of 108.06 mg of inactive cesium per gram of adsorbent. The adsorption isotherm is better fitted to the Freundlich model than the Langmuir model. In addition, kinetics studies show that the adsorption process is consistent with a pseudo second-order model. Furthermore, at equilibrium, the composite has an outstanding adsorption capacity of 99.24% for the radioactive cesium from aqueous solution. This may be ascribed to the fact that the AIP clay played a substantial role in protecting PB release from the P-MSC composite by cross-linking with alginate to improve the mechanical stability. Excellent adsorption capacity, easy separation, and good selectivity make the adsorbent suitable for the removal of radioactive cesium from seawater around nuclear plants and/or after nuclear accidents.

Synergistically strengthened 3D micro-scavenger cage adsorbent for selective removal of radioactive cesium

NASA Astrophysics Data System (ADS)

Jang, Sung-Chan; Kang, Sung-Min; Haldorai, Yuvaraj; Giribabu, Krishnan; Lee, Go-Woon; Lee, Young-Chul; Hyun, Moon Seop; Han, Young-Kyu; Roh, Changhyun; Huh, Yun Suk

2016-12-01

A novel microporous three-dimensional pomegranate-like micro-scavenger cage (P-MSC) composite has been synthesized by immobilization of iron phyllosilicates clay onto a Prussian blue (PB)/alginate matrix and tested for the removal of radioactive cesium from aqueous solution. Experimental results show that the adsorption capacity increases with increasing the inactive cesium concentration from 1 ppm to 30 ppm, which may be attributed to greater number of adsorption sites and further increase in the inactive cesium concentration has no effect. The P-MSC composite exhibit maximum adsorption capacity of 108.06 mg of inactive cesium per gram of adsorbent. The adsorption isotherm is better fitted to the Freundlich model than the Langmuir model. In addition, kinetics studies show that the adsorption process is consistent with a pseudo second-order model. Furthermore, at equilibrium, the composite has an outstanding adsorption capacity of 99.24% for the radioactive cesium from aqueous solution. This may be ascribed to the fact that the AIP clay played a substantial role in protecting PB release from the P-MSC composite by cross-linking with alginate to improve the mechanical stability. Excellent adsorption capacity, easy separation, and good selectivity make the adsorbent suitable for the removal of radioactive cesium from seawater around nuclear plants and/or after nuclear accidents.

Understanding Energy Absorption Behaviors of Nanoporous Materials

DTIC Science & Technology

2008-05-23

induced liquid infiltration in nanopores. J. Appl. Phys. 100, 014308.1-3 (2006). 26. Surani, F. B. and Qiao, Y. Energy absorption of a polyacrylic ...that the infiltration pressure decreases as the cation size increases (Fig.K-2). The ionic radii of cesium, potassium , sodium and lithium are...REPORT DOCUMENTATION PAGE Form Approved OMB NO. 0704-0188 Public Reporting burden for this collection of information is estimated to average 1 hour

The role of silica colloids on facilitated cesium transport through glass bead columns and modeling

NASA Astrophysics Data System (ADS)

Noell, Alan L.; Thompson, Joseph L.; Corapcioglu, M. Yavuz; Triay, Inés R.

1998-05-01

Groundwater colloids can act as a vector which enhances the migration of contaminants. While sorbed to mobile colloids, contaminants can be held in the aqueous phase which prevents them from interacting with immobile aquifer surfaces. In this study, an idealized laboratory set-up was used to examine the influence of amorphous silica colloids on the transport of cesium. Synthetic groundwater and saturated glass bead columns were used to minimize the presence of natural colloidal material. The columns were assembled in replicate, some packed with 150-210 μm glass bead and others packed with 355-420 μm glass beads. The colloids used in these experiments were 100 nm amorphous silica colloids from Nissan Chemical Company. In the absence of these colloids, the retardation factor for cesium was 8.0 in the 150-210 μm glass bead columns and 3.6 in the 355-420 μm glass bead columns. The influence of anthropogenic colloids was tested by injecting 0.09 pore volume slugs of an equilibrated suspension of cesium and colloids into the colloid-free columns. Although there was little noticeable facilitation in the smaller glass bead columns, there was a slight reduction in the retardation of cesium in the larger glass bead columns. This was attributed to cesium having less of a retention time in the larger glass bead columns. When cesium was injected into columns with a constant flux of colloids, the retardation of cesium was reduced by 14-32% in the 150-210 μm glass bead columns and by 38-51% in the 355-420 μm glass bead columns. A model based on Corapcioglu and Jiang (1993) [Corapcioglu, M.Y., Jiang, S., 1993. Colloid-facilitated groundwater contaminant transport, Water Resour. Res., 29 (7) 2215-2226] was compared with the experimental elution data. When equilibrium sorption expressions were used and the flux of colloids through the glass bead columns was constant, the colloid facilitated transport of cesium was able to be described using an effective retardation coefficient. Fully kinetic simulations, however, more accurately described the colloid facilitated transport of cesium.

A long-term stability study of Prussian blue: A quality assessment of water content and cesium binding.

PubMed

Mohammad, Adil; Yang, Yongsheng; Khan, Mansoor A; Faustino, Patrick J

2015-01-25

Prussian blue (PB) is the active pharmaceutical ingredient (API) of Radiogardase, the first approved medical countermeasure for the treatment of radiocesium poisoning in the event of a major radiological incident such as a "dirty bomb" or nuclear attack. The purpose of this study is to assess the long-term stability of Prussian blue drug products (DPs) and APIs under laboratory storage condition by monitoring the loss in water content and the in vitro cesium binding. The water content was measured by thermal gravimetric analysis (TGA). The in-vitro cesium binding study was conducted using a surrogate model to mimic gastric residence and intestinal transport. Free cesium was analyzed using a validated flame atomic emission spectroscopy (AES) method. The binding equilibrium was reached at 24h. The Langmuir isotherm was plotted to calculate the maximum binding capacity (MBC). Comparison of the same PB samples with 2003 data samples, the water content of both APIs and DPs decreased on an average by approximately 12-24%. Consequently, the MBC of cesium was decreased from 358mg/g in 2003 to 265mg/g @ pH 7.5, a decrease of approximately 26%. The binding of cesium is also pH dependent with lowest binding at pH 1.0 and maximum binding at pH 7.5. At pH 7.5, the amount of cesium bound decreased by an average value of 7.9% for APIs and 8.9% for DPs (for 600ppm initial cesium concentration). These findings of water loss, pH dependence and decrease in cesium binding are consistent with our previously published data in 2003. Over last 10 years the stored DPs and APIs of PB have lost about 20% of water which has a negative impact on the PB cesium binding, however PB still meets the FDA specification of >150mg/g at equilibrium. The study is the first quantitative assessment of the long-term stability of PB and directs that proper long-term and short-term storage of PB is required to ensure that it is safe and efficacious at the time of an emergency situation. Published by Elsevier B.V.

Cesium sorption reversibility and kinetics on illite, montmorillonite, and kaolinite

DOE PAGES

Durrant, Chad B.; Begg, James D.; Kersting, Annie B.; ...

2017-08-17

Understanding sorption and desorption processes is essential to predicting the mobility of radionuclides in the environment. In this study, we investigate adsorption/desorption of cesium in both binary (Cs + one mineral) and ternary (Cs + two minerals) experiments to study component additivity and sorption reversibility over long time periods (500 days). Binary Cs sorption experiments were performed with illite, montmorillonite, and kaolinite in a 5 mM NaCl/0.7 mM NaHCO3 solution (pH 8) and Cs concentration range of 10 –3 to 10 –11 M. The binary sorption experiments were followed by batch desorption experiments. The sorption behavior was modeled with themore » FIT4FD code and the results used to predict desorption behavior. Sorption to montmorillonite and kaolinite was linear over the entire concentration range but sorption to illite was non-linear, indicating the presence of multiple sorption sites. Based on the 14 day batch desorption data, cesium sorption appeared irreversible at high surface loadings in the case of illite but reversible at all concentrations for montmorillonite and kaolinite. Additionally, a novel experimental approach, using a dialysis membrane, was adopted in the ternary experiments, allowing investigation of the effect of a second mineral on Cs desorption from the original mineral. Cs was first sorbed to illite, montmorillonite or kaolinite, then a 3.5–5 kDalton Float-A-Lyzer® dialysis bag with 0.3 g of illite was introduced to each experiment inducing desorption. Nearly complete Cs desorption from kaolinite and montmorillonite was observed over the experiment, consistent with our equilibrium model, indicating complete Cs desorption from these minerals. Results from the long-term ternary experiments show significantly greater Cs desorption compared to the binary desorption experiments. Approximately ~ 45% of Cs desorbed from illite. However, our equilibrium model predicted ~ 65% desorption. Importantly, the data imply that in some cases, slow desorption kinetics rather than permanent fixation may play an important role in apparent irreversible Cs sorption.« less

Special treatment reduces helium permeation of glass in vacuum systems

NASA Technical Reports Server (NTRS)

Bryant, P. J.; Gosselin, C. M.

1966-01-01

Internal surfaces of the glass component of a vacuum system are exposed to cesium in gaseous form to reduce helium permeation. The cesium gas is derived from decomposition of cesium nitrate through heating. Several minutes of exposure of the internal surfaces of the glass vessel are sufficient to complete the treatment.

Hydrogen peroxide inhibits iodide uptake and iodine organification in cultured porcine thyroid follicles.

PubMed

Fukayama, H; Murakami, S; Nasu, M; Sugawara, M

1991-01-01

We investigated the effect of hydrogen peroxide on the process of thyroid hormone formation in a physiologic culture system of porcine thyroid follicles that we recently established. Porcine thyroid follicles cultured in medium containing 1 mU/mL TSH were exposed to 0 to 500 microM hydrogen peroxide in the presence of 0.1 microCi carrier-free Na125 and sodium iodide for 2 h. Iodide uptake and iodine organification were measured in this incubation system. The kinetics of iodide uptake were used to explain the action of hydrogen peroxide. In addition, cAMP content and Na+,K(+)-ATPase activity (an enzyme necessary for iodide uptake) were measured to investigate the mechanism of hydrogen peroxide action. Hydrogen peroxide at concentrations of 100, 200, and 500 microM inhibited iodide uptake in a dose-dependent manner. Iodide organification was inhibited only when the concentration of hydrogen peroxide was greater than 200 microM. The kinetics of iodide uptake indicated that hydrogen peroxide was a noncompetitive inhibitor with iodide. Inhibition of iodide uptake and iodine organification by hydrogen peroxide were not mediated by alteration of cAMP content of Na+,K(+)-ATPase activity, since exposure to even 500 microM hydrogen peroxide did not change these parameters in the follicle when compared with those of control samples. Our results suggest that the iodide transport system in the thyroid follicle is inhibited at 200 microM hydrogen peroxide or greater.

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

PubMed

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.

Phonon Mode Transformation across the Orthohombic-Tetragonal Phase Transition in a Lead-Iodide Perovskite CH3NH3PbI3: a Terahertz Time-Domain Spectroscopy Approach

NASA Astrophysics Data System (ADS)

Chia, Elbert E. M.; La-O-Vorakiat, Chan; Kadro, Jeannette; Salim, Teddy; Zhao, Daming; Ahmed, Towfiq; Lam, Yeng Ming; Zhu, Jian-Xin; Marcus, Rudolph; Michel-Beyerle, Maria-Elisabeth

Using terahertz time-domain spectroscopy (THz-TDS), we study the temperature-dependent phonon modes of the organometallic lead iodide perovskite CH3NH3PbI3 thin film across the terahertz (0.5-3 THz) and temperature (20-300 K) ranges. These modes are related to the vibration of the Pb-I bonds. We found that two phonon modes in the tetragonal phase at room temperature split into four modes in the low-temperature orthorhombic phase. By use of the Lorentz model fitting, we analyze the critical behavior of this phase transition. King Mongkut's University of Technology Thonburi (Grant No. SCI58-003), Singapore MOE Tier 1 (RG13/12, RG123/14), ONR, ARO, NTU Biophysics Center, LANL LDRD, LANL CINT.

40 CFR 415.510 - Applicability; description of the potassium iodide production subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... potassium iodide production subcategory. 415.510 Section 415.510 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Potassium Iodide Production Subcategory § 415.510 Applicability; description of the potassium iodide production subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 415.510 - Applicability; description of the potassium iodide production subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... potassium iodide production subcategory. 415.510 Section 415.510 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Potassium Iodide Production Subcategory § 415.510 Applicability; description of the potassium iodide production subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 415.510 - Applicability; description of the potassium iodide production subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... potassium iodide production subcategory. 415.510 Section 415.510 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Potassium Iodide Production Subcategory § 415.510 Applicability; description of the potassium iodide production subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 415.510 - Applicability; description of the potassium iodide production subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... potassium iodide production subcategory. 415.510 Section 415.510 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Potassium Iodide Production Subcategory § 415.510 Applicability; description of the potassium iodide production subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 415.510 - Applicability; description of the potassium iodide production subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... potassium iodide production subcategory. 415.510 Section 415.510 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Potassium Iodide Production Subcategory § 415.510 Applicability; description of the potassium iodide production subcategory. The provisions of this subpart are applicable to discharges...

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

EPA Science Inventory

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...

Use of an iodide-specific electrode to study lactoperoxidase-catalyzed iodination of l-tyrosine.

PubMed

Threatte, R M; Fregly, M J; Field, F P; Jones, P K

1979-12-01

An in vitro method employing an iodide-specific electrode for monitoring lactoperoxidase-catalyzed iodination is described. The method utilized lactoperoxidase, potassium iodide, and a glucose--glucose oxidase system for the generation of hydrogen peroxide and l-tyrosine. As iodination of l-tyrosine proceeded, the free iodide concentration in solution decreased and was monitored by an iodide-specific electrode. The iodide electrode was reliable when compared to a 131I-method for measuring free iodide changes in solution. Increasing concentrations of resorcinol, a well-known inhibitor of thyroid peroxidase-catalyzed iodination, in the reaction mixture resulted in graded inhibition of the initial rate of lactoperoxidase-catalyzed l-tyrosine iodination. This in vitro system can be used to assess inhibitory activity of various antithyroid substances.

Thermal stability study of a new guanidine suppressor for the next-generation caustic-side solvent extraction process

DOE PAGES

Hill, Talon G.; Ensor, Dale D.; Delmau, Lætitia Helene; ...

2016-02-06

Cesium stripping performance of thermally stressed solvent degrades slowly over time in batch tests of the Next Generation Caustic-Side Solvent Extraction (NGS) process. NGS is currently used at pilot scale at the Savannah River Site for the selective removal of cesium from high-level salt waste. Recently a new guanidine, N,N',N" -tris(3,7-dimethyloctyl)guanidine (TiDG), was chosen for use as the suppressor, a lipophilic organic base needed for stripping, and the present study was undertaken to address the question of its stability. The NGS process solvent was evaluated for a period of three months under a variety of temperature and storage conditions. Themore » performance of the solvent was tested at 30-day increments using a standard extraction, scrub, strip, and extraction (ES 2S 3E) sequence. Lastly, the results provide insight on the effects of storage and process conditions, the stripping behavior of TiDG, and the stability of the new solvent composition.« less

Desorption of cesium from granite under various aqueous conditions.

PubMed

Wang, Tsing-Hai; Li, Ming-Hsu; Wei, Yuan-Yaw; Teng, Shi-Ping

2010-12-01

In this work the desorption of cesium ions from crushed granite in synthetic groundwater (GW) and seawater (SW) was investigated. Results were compared with those obtained in deionized water (DW) and in two kinds of extraction solutions, namely: MgCl(2) and NaOAc (sodium acetate). In general, the desorption rate of Cs from crushed granite increased proportionally with initial Cs loadings. Also, amounts of desorbed Cs ions followed the tendency in the order SW>GW>NaOAc approximately equal MgCl(2)>DW solutions. This indicated that the utilization of extraction reagents for ion exchange will underestimate the Cs desorption behavior. Fitting these experimental data by Langmuir model showed that these extraction reagents have reduced Cs uptake by more than 90%, while only less than 1% of adsorbed Cs ions are still observed in GW and SW solutions in comparison to those in DW. Further SEM/EDS mapping studies clearly demonstrate that these remaining adsorbed Cs ions are at the fracture areas of biotite. Copyright 2010 Elsevier Ltd. All rights reserved.

Thermal stability study of a new guanidine suppressor for the next-generation caustic-side solvent extraction process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hill, Talon G.; Ensor, Dale D.; Delmau, Lætitia Helene

Cesium stripping performance of thermally stressed solvent degrades slowly over time in batch tests of the Next Generation Caustic-Side Solvent Extraction (NGS) process. NGS is currently used at pilot scale at the Savannah River Site for the selective removal of cesium from high-level salt waste. Recently a new guanidine, N,N',N" -tris(3,7-dimethyloctyl)guanidine (TiDG), was chosen for use as the suppressor, a lipophilic organic base needed for stripping, and the present study was undertaken to address the question of its stability. The NGS process solvent was evaluated for a period of three months under a variety of temperature and storage conditions. Themore » performance of the solvent was tested at 30-day increments using a standard extraction, scrub, strip, and extraction (ES 2S 3E) sequence. Lastly, the results provide insight on the effects of storage and process conditions, the stripping behavior of TiDG, and the stability of the new solvent composition.« less

Performance and modeling of cesium ion exchange by ENGI neered form crystalline silicotitanates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anthony, R.G.; Gu, D.; Huckman, M.

1996-10-01

TAM-5, a hydrous crystalline silicotitanate (CST) powder developed by Sandia National Laboratories and Texas A&M University, and commercialized by UOP as IONSIV{reg_sign} Ion Exchanger Type IE-910, is a highly selective material for removing cesium and strontium from aqueous radioactive wastes such as those found at the Hanford site in Washington. An engineered form of the material suitable for column ion exchange type operations has been developed and tested. Data relevant to processing radioactive tank wastes including equilibrium distribution coefficients and column testing will be presented. The impact of exposure of the engineered form to chemically aggressive environments such as itmore » might experience during waste processing, and to the less aggressive environments it might experience during post processing storage has been assessed. The thermal stability of the material has also been evaluated. The experimental results have been integrated with an effort to model the material`s equilibrium and kinetic behavior.« less

Phase 2 Methyl Iodide Deep-Bed Adsorption Tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soelberg, Nick; Watson, Tony

2014-09-01

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

Relationship of dietary iodide and drinking water disinfectants to thyroid function in experimental animals.

PubMed Central

Revis, N W; McCauley, P; Holdsworth, G

1986-01-01

The importance of dietary iodide on the reported hypothyroid effect of drinking water disinfectants on thyroid function was investigated. Previous studies have also showed differences in the relative sensitivity of pigeons and rabbits to chlorinated water. Pigeons and rabbits were exposed for 3 months to diets containing high (950 ppb) or low (300 ppb) levels of iodide and to drinking water containing two levels of chlorine. Results showed that the high-iodide diet prevented the hypothyroid effect observed in pigeons given the low-iodide diet and chlorinated drinking water. Similar trends were observed in rabbits exposed to the same treatment; however, significant hypothyroid effects were not observed in this animal model. The factor associated with the observed effect of dietary iodide on the chlorine-induced change in thyroid function is unknown, as is the relative sensitivity of rabbits and pigeons to the effect of chlorine. Several factors may explain the importance of dietary iodide and the relative sensitivity of these species. For example, the iodine formed by the known reaction of chlorine with iodide could result in a decrease in the plasma level of iodide because of the relative absorption rates of iodide and iodine in the intestinal tract, and the various types and concentrations of chloroorganics (metabolites) formed in the diet following the exposure of various dietary constituents to chlorine could affect the thyroid function. The former factor was investigated in the present studies. Results do not confirm a consistent, significant reduction in the plasma level of iodide in rabbits and pigeons exposed to chlorinated water and the low-iodide diet. The latter factor is being investigated. PMID:3816728

The effect of mineral composition on the sorption of cesium ions on geological formations.

PubMed

Kónya, József; Nagy, Noémi M; Nemes, Zoltán

2005-10-15

The sorption of cesium-137 on rock samples, mainly on clay rocks, is determined as a function of the mineral composition of the rocks. A relation between the mineral groups (tectosilicates, phyllosilicates, clay minerals, carbonates) and their cesium sorption properties is shown. A linear model is constructed by which the distribution coefficients of the different minerals can be calculated from the mineral composition and the net distribution coefficient of the rock. On the basis of the distribution coefficients of the minerals the cesium sorption properties of other rocks can be predicted.

Carbonation-induced weathering effect on cesium retention of cement paste

NASA Astrophysics Data System (ADS)

Park, S. M.; Jang, J. G.

2018-07-01

Carbonation is inevitable for cement and concrete in repositories over an extended period of time. This study investigated the carbonation-induced weathering effect on cesium retention of cement. Cement paste samples were exposed to accelerated carbonation for different durations to simulate the extent of weathering among samples. The extent of carbonation in cement was characterized by XRD, TG and NMR spectroscopy, while the retention capacity for cesium was investigated by zeta potential measurement and batch adsorption tests. Though carbonation led to decalcification from the binder gel, it negatively charged the surface of cement hydrates and enhanced their cesium adsorption capacity.

Test procedures and instructions for single shell tank saltcake cesium removal with crystalline silicotitanate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duncan, J.B.

1997-01-07

This document provides specific test procedures and instructions to implement the test plan for the preparation and conduct of a cesium removal test, using Hanford Single Shell Tank Saltcake from tanks 24 t -BY- I 10, 24 1 -U- 108, 24 1 -U- 109, 24 1 -A- I 0 1, and 24 t - S-102, in a bench-scale column. The cesium sorbent to be tested is crystalline siticotitanate. The test plan for which this provides instructions is WHC-SD-RE-TP-024, Hanford Single Shell Tank Saltcake Cesium Removal Test Plan.

ION ROCKET ENGINE

DOEpatents

Ehlers, K.W.; Voelker, F. III

1961-12-19

A thrust generating engine utilizing cesium vapor as the propellant fuel is designed. The cesium is vaporized by heat and is passed through a heated porous tungsten electrode whereby each cesium atom is fonized. Upon emergfng from the tungsten electrode, the ions are accelerated rearwardly from the rocket through an electric field between the tungsten electrode and an adjacent accelerating electrode grid structure. To avoid creating a large negative charge on the space craft as a result of the expulsion of the positive ions, a source of electrons is disposed adjacent the ion stream to neutralize the cesium atoms following acceleration thereof. (AEC)

Results of Several Years Experiments on the Absorption of Radioactive Strontium and Cesium by Cultivated Plants; COMPTE RENDU D'EXPERIENCES DE PLUSIEURS ANNEES SUR L'ABSORPTION DU STRONTIUM ET DU CESIUM RADIOACTIES PAR DES PLANTES CULTIVEES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huguet, F. et al.

1962-01-01

The absorption of cesium-137 and strontium-90 by vines, permanent pasture, potatoes, green vegetables, tomatoes, onions, cabbage, and beans in France in 1960 is presented. The strontium coefficient has varied very little from one year to the next and that of cesium has slightly diminished. The values obtained suggest that the concentrations in irrigation water should not exceed one fifth of the maximum permissible concentration in drinking water. (auth)

Modeling of thermo-mechanical and irradiation behavior of mixed oxide fuel for sodium fast reactors

NASA Astrophysics Data System (ADS)

Karahan, Aydın; Buongiorno, Jacopo

2010-01-01

An engineering code to model the irradiation behavior of UO2-PuO2 mixed oxide fuel pins in sodium-cooled fast reactors was developed. The code was named fuel engineering and structural analysis tool (FEAST-OXIDE). FEAST-OXIDE has several modules working in coupled form with an explicit numerical algorithm. These modules describe: (1) fission gas release and swelling, (2) fuel chemistry and restructuring, (3) temperature distribution, (4) fuel-clad chemical interaction and (5) fuel-clad mechanical analysis. Given the fuel pin geometry, composition and irradiation history, FEAST-OXIDE can analyze fuel and cladding thermo-mechanical behavior at both steady-state and design-basis transient scenarios. The code was written in FORTRAN-90 program language. The mechanical analysis module implements the LIFE algorithm. Fission gas release and swelling behavior is described by the OGRES and NEFIG models. However, the original OGRES model has been extended to include the effects of joint oxide gain (JOG) formation on fission gas release and swelling. A detailed fuel chemistry model has been included to describe the cesium radial migration and JOG formation, oxygen and plutonium radial distribution and the axial migration of cesium. The fuel restructuring model includes the effects of as-fabricated porosity migration, irradiation-induced fuel densification, grain growth, hot pressing and fuel cracking and relocation. Finally, a kinetics model is included to predict the clad wastage formation. FEAST-OXIDE predictions have been compared to the available FFTF, EBR-II and JOYO databases, as well as the LIFE-4 code predictions. The agreement was found to be satisfactory for steady-state and slow-ramp over-power accidents.

Atomic force microscopy of lead iodide crystal surfaces

NASA Astrophysics Data System (ADS)

George, M. A.; Azoulay, M.; Jayatirtha, H. N.; Biao, Y.; Burger, A.; Collins, W. E.; Silberman, E.

1994-03-01

Atomic force microscopy (AFM) was used to characterize the surface of lead iodide crystals. The high vapor pressure of lead iodide prohibits the use of traditional high resolution surface study techniques that require high vacuum conditions. AFM was used to image numerous insulating surface in various ambients, with very little sample preparation techniques needed. Freshly cleaved and modified surfaces, including, chemical and vacuum etched, and air aged surfaces, were examined. Both intrinsic and induced defects were imaged with high resolution. The results were compared to a similar AFM study of mercuric iodide surfaces and it was found that, at ambient conditions, lead iodide is significantly more stable than mercuric iodide.

Direct vapor/solid synthesis of mercuric iodide using compounds of mercury and iodine

DOEpatents

Skinner, Nathan L.

1990-01-01

A process is disclosed for producing high purity mercuric iodide by passing a gaseous source of a mercuric compound through a particulate bed of a low vapor pressure iodide compound which is maintained at an elevated temperature which is the lower of either: (a) just below the melting or volatilization temperature of the iodide compound (which ever is lower); or (b) just below the volatilization point of the other reaction product formed during the reaction; to cause the mercuric compound to react with the iodide compound to form mercuric iodide which then passes as a vapor out of the bed into a cooler condensation region.

Iodide handling by the thyroid epithelial cell.

PubMed

Nilsson, M

2001-01-01

Iodination of thyroglobulin, the key event in the synthesis of thyroid hormone, is an extracellular process that takes place inside the thyroid follicles at the apical membrane surface that faces the follicular lumen. The supply of iodide involves two steps of TSH-regulated transport, basolateral uptake and apical efflux, that imprint the polarized phenotype of the thyroid cell. Iodide uptake is generated by the sodium/iodide symporter present in the basolateral plasma membrane. A candidate for the apical iodide-permeating mechanism is pendrin, a chloride/iodide transporting protein recently identified in the apical membrane. In physiological conditions, transepithelial iodide transport occurs without intracellular iodination, despite the presence of large amounts of thyroglobulin and thyroperoxidase inside the cells. The reason is that hydrogen peroxide, serving as electron acceptor in iodide-protein binding and normally produced at the apical cell surface, is rapidly degraded by cytosolic glutathione peroxidase once it enters the cells. Iodinated thyroglobulin in the lumen stores not only thyroid hormone but iodine incorporated in iodotyrosine residues as well. After endocytic uptake and degradation of thyroglobulin, intracellular deiodination provides a mechanism for recycling of iodide to participate in the synthesis of new thyroid hormone at the apical cell surface.

Demonstration of Iodide Transport Defect but Normal Iodide Organification in Nonfunctioning Nodules of Human Thyroid Glands

PubMed Central

Field, James B.; Larsen, P. Reed; Yamashita, Kamejiro; Mashiter, Keith; Dekker, Andrew

1973-01-01

Benign and malignant nodules in human thyroid glands, which did not concentrate iodide in vivo, were also unable to accumulate iodide in vitro. The mean thyroid-to-medium ratio (T/M) in seven benign nodules was 0.8±0.2 compared with 7±2 in adjacent normal thyroid tissue. In four malignant thyroid nodules, the mean T/M was 0.5±0.1 compared with 11±4 in adjacent normal thyroid. Despite the inability of such nodules to concentrate iodide, iodide organification was present but was only one-half to one-third as active as in surrounding normal thyroid. Thyroid-stimulating hormone (TSH) increased iodide organification equally in both benign nodules and normal thyroid although it had no effect in three of the four malignant lesions. The reduction in organification is probably related to the absence of iodide transport, since incubation of normal thyroid slices with perchlorate caused similar diminution in iodide incorporation but no change in the response to TSH. Monoiodotyrosine (MIT) and di-iodotyrosine (DIT) accounted for most of the organic iodide in both the nodules and normal tissue. The MIT/DIT ratio was similar in normal and nodule tissue. The normal tissue contained much more inorganic iodide than the nodules, consistent with the absence of the iodide trap in the latter tissue. The thyroxine content of normal thyroid was 149±17 μg/g wet wt and 18±4 μg/g wet wt in the nodules. The transport defect in the nodules was not associated with any reduction in total, Na+-K+- or Mg++-activated ATPase activities or the concentration of ATP. Basal adenylate cyclase was higher in nodules than normal tissue. Although there was no difference between benign and malignant nodules, the response of adenylate cyclase to TSH was greater in the benign lesions. These studies demonstrate that nonfunctioning thyroid nodules, both benign and malignant, have a specific defect in iodide transport that accounts for their failure to accumulate radioactive iodide in vivo. In benign nodules, iodide organification was increased by TSH while no such effect was found in three of four malignant lesions, suggesting additional biochemical defects in thyroid carcinomas. PMID:4353998

The effect of temperature and radiation on the cesium adsorption ability of IONSIV/256 IE-910 and IONSIV/256 IE-911

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, K.B.

1999-12-08

This study examined the ion exchange capacity of crystalline silicotitanate in a simulated waste solution. The focus areas included the effect of temperature and radiation on cesium sorption capacity. The cesium is expected to be removed from high-level radioactive wastes using these ion exchange materials.

An Inorganic Microsphere Composite for the Selective Removal of Cesium 137 from Acidic Nuclear Waste Solutions - Parts 1 and 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

T. J. Tranter; T. A. Vereschchagina; V. Utgikar

2009-03-01

A new inorganic ion exchange composite for removing radioactive cesium from acidic waste streams has been developed. The new material consists of ammonium molybdophosphate, (NH4)3P(Mo3O10)4•3H2O (AMP), synthesized within hollow aluminosilicate microspheres (AMP-C), which are produced as a by-product from coal combustion. The selective cesium exchange capacity of this inorganic composite was evaluated in bench-scale column tests using simulated sodium bearing waste solution as a surrogate for the acidic tank waste currently stored at the Idaho National Laboratory (INL). Total cesium loading on the columns at saturation agreed very well with equilibrium values predicted from isotherm experiments performed previously. A numericalmore » algorithm for solving the governing partial differential equations (PDE) for cesium uptake was developed using the intraparticle mass transfer coefficient obtained from previous batch kinetic experiments. Solutions to the governing equations were generated to obtain the cesium concentration at the column effluent as a function of throughput volume using the same conditions as those used for the actual column experiments. The numerical solutions of the PDE fit the column break through data quite well for all the experimental conditions in the study. The model should therefore provide a reliable prediction of column performance at larger scales. A new inorganic ion exchange composite consisting of ammonium molybdophosphate, (NH4)3P(Mo3O10)4•3H2O (AMP), synthesized within hollow aluminosilicate microspheres (AMP-C) has been developed. Two different batches of the sorbent were produced resulting in 20% and 25% AMP loading for two and three loading cycles, respectively. The selective cesium exchange capacity of this inorganic composite was evaluated using simulated sodium bearing waste solution as a surrogate for the acidic tank waste currently stored at the Idaho National Laboratory (INL). Equilibrium isotherms obtained from these experiments were very favorable for cesium uptake and indicated maximum cesium loading of approximately 9 % by weight of dry AMP. Batch kinetic experiments were also performed to obtain the necessary data to estimate the effective diffusion coefficient for cesium in the sorbent particle. These experiments resulted in effective intraparticle cesium diffusivity coefficients of 4.99 x 10-8 cm2/min and 4.72 x 10-8 cm2/min for the 20% and 25 % AMP-C material, respectively.« less

The Effect of Pressure and Organic Constituents on the Cesium Ion Exchange Performance of IONSIV IE-911

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fondeur, F.F.

2000-07-18

This study examined cesium ({sup 137}Cs) ion exchange of crystalline silicotitanate (CST) in simulated waste solution. In particular, the study focused on the effect of CST pretreatment on the kinetics and extent of cesium adsorption. The test used IONSIV{reg_sign}IE-911 (UOP LLC, Molecular Sieves Division, Des Plaines, IL), the engineered form of CST. Pretreatment steps examined include: soaking CST in 2M NaOH solution for three days, exposing CST to 50% relative humidity for one week, flowing organic-containing (saturated) salt solution through a CST packed bed (at 5 cm/min. superficial velocity), or drying CST in air at 100 C for three days.more » Some tests occurred under 50 and 25 psig of argon. The following conclusions summarize the results. Pretreatment of IE-911 in organic-containing (e.g., tri-n-butyl phosphate, dibutylphosphate, butanol, paraffin and Dow Corning H-10 defoamer) simulated waste or simulated waste yielded a 83% slower rate of cesium adsorption and 56% lower cesium capacity after one week. Pretreatment of IE-911 in 2M caustic solution for 48 hours yielded a slower approach to equilibrium cesium distribution in batch contact tests--7.7 mL/(g*h) during the first 48 hours and 2.4 ml/(g*h) thereafter. Carboxylates and adsorbed carbonates inside the pores likely affect the cesium transport by either increasing the path-length or reducing mass transfer rate. Heating IE-911 as received from the vendor at 100 C for 24 hours significantly degraded its cesium removal performance by a 40.7% reduction in capacity and 43% reduction in sorption rate over one week of testing. Testing determined nearly identical distribution coefficients K{sub d} between lot {number_sign} 9990-9681-0004 and 9990-9881-0005 (i.e., difference of only 5.6%). Tests measuring water insertion rates into IE-911 show that hydration of the IE-911 does not appear to limit the rate of cesium sorption. Increasing the atmospheric pressure from 0 to 50 psig had no effect on cesium sorption. Note that lower apparent capacity or slower cesium sorption rate in these limited-duration batch contact tests as a result of pretreatment do not necessarily imply reduced dynamic performance in a flowing ion-exchange application. The experiments that provided the bases for the currently proposed facility design used caustic-pretreated IE-911. Another report will assess whether the presence of the organic compounds in the waste solution impeded column performance.« less

Simulation of Sediment and Cesium Transport in the Ukedo River and the Ogi Dam Reservoir during a Rainfall Event using the TODAM Code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onishi, Yasuo; Yokuda, Satoru T.; Kurikami, Hiroshi

2014-03-28

The accident at the Fukushima Daiichi Nuclear Power Plant in March 2011 caused widespread environmental contamination. Although decontamination activities have been performed in residential areas of the Fukushima area, decontamination of forests, rivers, and reservoirs is still controversial because of the economical, ecological, and technical difficulties. Thus, an evaluation of contaminant transport in such an environment is important for safety assessment and for implementation of possible countermeasures to reduce radiation exposure to the public. The investigation revealed that heavy rainfall events play a significant role in transporting radioactive cesium deposited on the land surface, via soil erosion and sediment transportmore » in rivers. Therefore, we simulated the sediment and cesium transport in the Ukedo River and its tributaries in Fukushima Prefecture, including the Ogaki Dam Reservoir, and the Ogi Dam Reservoir of the Oginosawa River in Fukushima Prefecture during and after a heavy rainfall event by using the TODAM (Time-dependent, One-dimensional Degradation And Migration) code. The main outcomes are the following: • Suspended sand is mostly deposited on the river bottom. Suspended silt and clay, on the other hand, are hardly deposited in the Ukedo River and its tributaries except in the Ogaki Dam Reservoir in the Ukedo River even in low river discharge conditions. • Cesium migrates mainly during high river discharge periods during heavy rainfall events. Silt and clay play more important roles in cesium transport to the sea than sand does. • The simulation results explain variations in the field data on cesium distributions in the river. Additional field data currently being collected and further modeling with these data may shed more light on the cesium distribution variations. • Effects of 40-hour heavy rainfall events on clay and cesium transport continue for more than a month. This is because these reservoirs slow down the storm-induced high flow moving through these reservoirs. • The reservoirs play a major role as a sink of sediment and cesium in the river systems. Some amounts of sediment pass through them along with cesium in dissolved and clay-sorbed cesium forms. • Effects of countermeasures such as overland decontamination, dam control and sorbent injection were tentatively estimated. The simulation suggested that overland decontamination and sorbent injection would be effective for decreasing the contamination of water in the reservoir and in the river below the dam.« less

Superoxide Production by a Manganese-Oxidizing Bacterium Facilitates Iodide Oxidation

PubMed Central

Li, Hsiu-Ping; Daniel, Benjamin; Creeley, Danielle; Grandbois, Russell; Zhang, Saijin; Xu, Chen; Ho, Yi-Fang; Schwehr, Kathy A.; Kaplan, Daniel I.; Santschi, Peter H.; Hansel, Colleen M.

2014-01-01

The release of radioactive iodine (i.e., iodine-129 and iodine-131) from nuclear reprocessing facilities is a potential threat to human health. The fate and transport of iodine are determined primarily by its redox status, but processes that affect iodine oxidation states in the environment are poorly characterized. Given the difficulty in removing electrons from iodide (I−), naturally occurring iodide oxidation processes require strong oxidants, such as Mn oxides or microbial enzymes. In this study, we examine iodide oxidation by a marine bacterium, Roseobacter sp. AzwK-3b, which promotes Mn(II) oxidation by catalyzing the production of extracellular superoxide (O2−). In the absence of Mn2+, Roseobacter sp. AzwK-3b cultures oxidized ∼90% of the provided iodide (10 μM) within 6 days, whereas in the presence of Mn(II), iodide oxidation occurred only after Mn(IV) formation ceased. Iodide oxidation was not observed during incubations in spent medium or with whole cells under anaerobic conditions or following heat treatment (boiling). Furthermore, iodide oxidation was significantly inhibited in the presence of superoxide dismutase and diphenylene iodonium (a general inhibitor of NADH oxidoreductases). In contrast, the addition of exogenous NADH enhanced iodide oxidation. Taken together, the results indicate that iodide oxidation was mediated primarily by extracellular superoxide generated by Roseobacter sp. AzwK-3b and not by the Mn oxides formed by this organism. Considering that extracellular superoxide formation is a widespread phenomenon among marine and terrestrial bacteria, this could represent an important pathway for iodide oxidation in some environments. PMID:24561582

Superoxide production by a manganese-oxidizing bacterium facilitates iodide oxidation.

PubMed

Li, Hsiu-Ping; Daniel, Benjamin; Creeley, Danielle; Grandbois, Russell; Zhang, Saijin; Xu, Chen; Ho, Yi-Fang; Schwehr, Kathy A; Kaplan, Daniel I; Santschi, Peter H; Hansel, Colleen M; Yeager, Chris M

2014-05-01

The release of radioactive iodine (i.e., iodine-129 and iodine-131) from nuclear reprocessing facilities is a potential threat to human health. The fate and transport of iodine are determined primarily by its redox status, but processes that affect iodine oxidation states in the environment are poorly characterized. Given the difficulty in removing electrons from iodide (I(-)), naturally occurring iodide oxidation processes require strong oxidants, such as Mn oxides or microbial enzymes. In this study, we examine iodide oxidation by a marine bacterium, Roseobacter sp. AzwK-3b, which promotes Mn(II) oxidation by catalyzing the production of extracellular superoxide (O2(-)). In the absence of Mn(2+), Roseobacter sp. AzwK-3b cultures oxidized ∼90% of the provided iodide (10 μM) within 6 days, whereas in the presence of Mn(II), iodide oxidation occurred only after Mn(IV) formation ceased. Iodide oxidation was not observed during incubations in spent medium or with whole cells under anaerobic conditions or following heat treatment (boiling). Furthermore, iodide oxidation was significantly inhibited in the presence of superoxide dismutase and diphenylene iodonium (a general inhibitor of NADH oxidoreductases). In contrast, the addition of exogenous NADH enhanced iodide oxidation. Taken together, the results indicate that iodide oxidation was mediated primarily by extracellular superoxide generated by Roseobacter sp. AzwK-3b and not by the Mn oxides formed by this organism. Considering that extracellular superoxide formation is a widespread phenomenon among marine and terrestrial bacteria, this could represent an important pathway for iodide oxidation in some environments.

Linking loss of sodium-iodide symporter expression to DNA damage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lyckesvärd, Madeleine Nordén; Department of Medical Chemistry and Cell Biology, University of Gothenburg, Göteborg; Kapoor, Nirmal

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 andmore » 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.« less

Efficient removal of cesium from low-level radioactive liquid waste using natural and impregnated zeolite minerals.

PubMed

Borai, E H; Harjula, R; Malinen, Leena; Paajanen, Airi

2009-12-15

The objective of the proposed work was focused to provide promising solid-phase materials that combine relatively inexpensive and high removal capacity of some radionuclides from low-level radioactive liquid waste (LLRLW). Four various zeolite minerals including natural clinoptilolite (NaNCl), natural chabazite (NaNCh), natural mordenite (NaNM) and synthetic mordenite (NaSM) were investigated. The effective key parameters on the sorption behavior of cesium (Cs-134) were investigated using batch equilibrium technique with respect to the waste solution pH, contacting time, potassium ion concentration, waste solution volume/sorbent weight ratio and Cs ion concentration. The obtained results revealed that natural chabazite (NaNCh) has the higher distribution coefficients and capacity towards Cs ion rather than the other investigated zeolite materials. Furthermore, novel impregnated zeolite material (ISM) was prepared by loading Calix [4] arene bis(-2,3 naphtho-crown-6) onto synthetic mordenite to combine the high removal uptake of the mordenite with the high selectivity of Calix [4] arene towards Cs radionuclide. Comparing the obtained results for both NaSM and the impregnated synthetic mordenite (ISM-25), it could be observed that the impregnation process leads to high improvement in the distribution coefficients of Cs+ ion (from 0.52 to 27.63 L/g). The final objective in all cases was aimed at determining feasible and economically reliable solution to the management of LLRLW specifically for the problems related to the low decontamination factor and the effective recovery of monovalent cesium ion.

21 CFR 582.5634 - Potassium iodide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Potassium iodide. 582.5634 Section 582.5634 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5634 Potassium iodide. (a) Product. Potassium iodide. (b) Tolerance. 0.01 percent. (c...

21 CFR 184.1634 - Potassium iodide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Potassium iodide. 184.1634 Section 184.1634 Food... GRAS § 184.1634 Potassium iodide. (a) Potassium iodide (KI, CAS Reg. No. 7681-11-0) is the potassium... reacting hydriodic acid (HI) with potassium bicarbonate (KHCO3). (b) The ingredient meets the...

21 CFR 582.5634 - Potassium iodide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Potassium iodide. 582.5634 Section 582.5634 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5634 Potassium iodide. (a) Product. Potassium iodide. (b) Tolerance. 0.01 percent. (c...

Efficient non-linear two-photon effects from the Cesium 6D manifold

NASA Astrophysics Data System (ADS)

Haluska, Nathan D.; Perram, Glen P.; Rice, Christopher A.

2018-02-01

We report several non-linear process that occur when two-photon pumping the cesium 6D states. Cesium vapor possess some of the largest two-photon pump cross sections in nature. Pumping these cross sections leads to strong amplified spontaneous emission that we observe on over 17 lasing lines. These new fields are strong enough to couple with the pump to create additional tunable lines. We use a heat pipe with cesium densities of 1014 to 1016 cm-3 and 0 to 5 Torr of helium buffer gas. The cesium 6D States are interrogated by both high energy pulses and low power CW sources. We observe four-wave mixing, six-wave mixing, potential two-photon lasing, other unknown nonlinear processes, and the persistence of some processes at low thresholds. This system is also uniquely qualified to support two-photon lasing under the proper conditions.

Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium.

PubMed

Hu, Baiyang; Fugetsu, Bunshi; Yu, Hongwen; Abe, Yoshiteru

2012-05-30

We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/Prussian-blue), spongiform adsorbent with an in situ foaming procedure. Prussian blue was permanently immobilized in the cell walls of the spongiform matrix and preferentially adsorbed cesium with a theoretical capacity of 167 mg/g cesium. Cesium was absorbed primarily by an ion-exchange mechanism, and the absorption was accomplished by self-uptake of radioactive water by the quaternary spongiform adsorbent. Copyright © 2012 Elsevier B.V. All rights reserved.

Biological effects of cesium-137 injected in beagle dogs of different ages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nikula, K.J.; Muggenburg, B.A.; Griffith, W.C.

1995-12-01

The toxicity of cesium-137 ({sup 137}Cs) in the Beagle dog was investigated at the Argonne National Laboratory (ANL) as part of a program to evaluate the biological effects of internally deposited radionuclides. The toxicity and health effects of {sup 137}Cs are important to understand because {sup 137}Cs is produced in large amounts in light-water nuclear reactors. Large quantities of cesium radioisotopes have entered the human food chain as a result of atmospheric nuclear weapons test, and additional cesium radioisotopes were released during the Chernobyl accident. Although the final analyses are not complete, three findings are significant: older dogs dies significantlymore » earlier than juvenile and young adult dogs; greater occurrence of sarcomas in the cesium-137 injected dogs; the major nonneoplastic effect in dogs surviving beyond 52 d appears to be testicular atrophy.« less

Synchrotron-Radiation Photoemission Study of Electronic Structures of a Cs-Doped Rubrene Surface

NASA Astrophysics Data System (ADS)

Cheng, Chiu-Ping; Lu, Meng-Han; Chu, Yu-Ya; Pi, Tun-Wen

Using synchrotron-radiation photoemission spectroscopy, we have studied the electronic structure of a cesium-doped rubrene thin film. The addition of cesium atoms causes the movement of the valence-band spectra and the change in line shapes at different concentration that can be separated into four different stages. In the first stage, the cesium atoms continuously diffuse into the substrate, and the Fermi level moves in the energy gap as a result of an electron transferred from the cesium to the rubrene. The second stage, in which the shifts of the spectra are interrupted, is characterized by the introduction of two in-gap states. When increasing doping of cesium into the third stage, the spectra move again; whereas, the line shapes maintain at the stoichiometric ratio of one. In the fourth stage, new in-gap states appear, which are the highest occupied molecular orbital (HOMO) and HOMO+1 states of (rubrene)2- anion.

Experimental and theoretical investigation for the suppression of the plasma arc drop in the thermionic converter

NASA Technical Reports Server (NTRS)

Shaw, D. T.; Manikopoulos, C. N.; Chang, T.; Lee, C. H.; Chiu, N.

1977-01-01

Ion generation and recombination mechanisms in the cesium plasma as they pertain to the advanced mode thermionic energy converter were studied. The decay of highly ionized cesium plasma was studied in the near afterglow to examine the recombination processes. Very low recombination in such a plasma may prove to be of considerable importance in practical converters. The approaches of external cesium generation were vibrationally excited nitrogen as an energy source of ionization of cesium ion, and microwave power as a means of resonant sustenance of the cesium plasma. Experimental data obtained so far show that all three techniques - i.e., the non-LTE high-voltage pulsing, the energy transfer from vibrationally excited diatomic gases, and the external pumping with a microwave resonant cavity - can produce plasmas with their densities significantly higher than the Richardson density. The implication of these findings as related to Lam's theory is discussed.

Radiochemical determination of strontium-90 and cesium-137 in waters of the Pacific Ocean and its neighboring seas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borisenko, G.S.; Kandinskii, P.A.; Gedeonov, L.I.

1987-03-01

Depending on the salinity of the water, two versions of strontium-90 and cesium-137 concentration from water samples are presented. Cesium-137 was concentrated by precipitating sparingly soluble mixed hexacyanoferrates (II), and strontium-90 by precipitating carbonates together with calcium. A scheme has been given for radiochemical analysis of the concentrates. Strontium-90 and cesium-137 contents in the waters of the Pacific Ocean and its neighboring seas have been determined by the radiochemical method described. The levels of radionuclide content in the water and atmospheric precipitations have been shown to be inter-related. Strontium-90 and cesium-137 contents in the surface water of the northwestern Pacificmore » were found to be much lower in 1980 than in the early seventies. The area of technogenic radioactive pollution was found to persist in the region of the Columbia mouth into the Pacific Ocean.« less

Removal of Radionuclides from Waste Water at Fukushima Daiichi Nuclear Power Plant: Desalination and Adsorption Methods - 13126

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kani, Yuko; Kamosida, Mamoru; Watanabe, Daisuke

Waste water containing high levels of radionuclides due to the Fukushima Daiichi Nuclear Power Plant accident, has been treated by the adsorption removal and reverse-osmosis (RO) desalination to allow water re-use for cooling the reactors. Radionuclides in the waste water are collected in the adsorbent medium and the RO concentrate (RO brine) in the water treatment system currently operated at the Fukushima Daiichi site. In this paper, we have studied the behavior of radionuclides in the presently applied RO desalination system and the removal of radionuclides in possible additional adsorption systems for the Fukushima Daiichi waste water treatment. Regarding themore » RO desalination system, decontamination factors (DFs) of the elements present in the waste water were obtained by lab-scale testing using an RO unit and simulated waste water with non-radioactive elements. The results of the lab-scale testing using representative elements showed that the DF for each element depended on its hydrated ionic radius: the larger the hydrated ionic radius of the element, the higher its DF is. Thus, the DF of each element in the waste water could be estimated based on its hydrated ionic radius. For the adsorption system to remove radionuclides more effectively, we studied adsorption behavior of typical elements, such as radioactive cesium and strontium, by various kinds of adsorbents using batch and column testing. We used batch testing to measure distribution coefficients (K{sub d}s) for cesium and strontium onto adsorbents under different brine concentrations that simulated waste water conditions at the Fukushima Daiichi site. For cesium adsorbents, K{sub d}s with different dependency on the brine concentration were observed based on the mechanism of cesium adsorption. As for strontium, K{sub d}s decreased as the brine concentration increased for any adsorbents which adsorbed strontium by intercalation and by ion exchange. The adsorbent titanium oxide had higher K{sub d}s and it was used for the column testing to obtain breakthrough curves under various conditions of pH and brine concentration. The breakthrough point had a dependency on pH and the brine concentration. We found that when the pH was higher or the brine concentration was lower, the longer it took to reach the breakthrough point. The inhibition of strontium adsorption by alkali earth metals would be diminished for conditions of higher pH and lower brine concentration. (authors)« less

Mesophase stabilization in ionic liquid crystals through pairing equally shaped mesogenic cations and anions

DOE PAGES

Stappert, Kathrin; Lipinski, Gregor; Kopiec, Gabriel; ...

2015-07-23

The synthesis and properties of a set of novel ionic liquid crystals with congruently shaped cations and anions are reported to check whether pairing mesogenic cations with mesogenic anions leads to a stabilization of a liquid crystalline phase. To that avail 1-alkyl-3-methyl-triazolium cations with an alkyl chain length of 10, 12, and 14 carbon atoms have been combined with p-alkyloxy-benzenesulfonate anions with different alkyl chain lengths (n = 10, 12, and 14). The corresponding triazolium iodides have been synthesized as reference compounds where the cation and anion have strong size and shape mismatch. The mesomorphic behavior of all compounds ismore » studied by differential scanning calorimetry and polarizing optical microscopy. All compounds except 1-methyl-3-decyltriazolium iodide, which qualifies as an ionic liquid, are thermotropic ionic liquid crystals. All other compounds adopt smectic A phases. As a result, a comparison of the thermal phase behavior of the 1-methyl-3-decyltriazolium bromides to the corresponding p-alkoxy-benzensulfonates reveals that definitely the mesophase is stabilized by pairing the rod-shaped 1-alkyl-3-methyltriazolium cation with a rod-like anion of similar size.« less

Influence of the anion nature and alkyl substituents in the behavior of ionic liquids derived from phenylpyridines

NASA Astrophysics Data System (ADS)

Dreyse, Paulina; Alarcón, Antonia; Galdámez, Antonio; González, Iván; Cortés-Arriagada, Diego; Castillo, Francisco; Mella, Andy

2018-02-01

Quaternary alkyl 2-phenylpyridinium and 2-(2,4-difluorophenyl)pyridinium amines with iodide, hexafluorophosphate and bis(trifluoromethylsulfonyl)imide anions have been fully characterized by 1H NMR, FT-IR and MALDI mass spectroscopic methods and studied by quantum chemistry calculations. The compounds with bis(trifluoromethylsulfonyl)imide anion can be classified as ionic liquids, because they melt at room temperature. The quaternary amines with iodide and hexafluorophosphate anions are solid at 25 °C. The X-ray diffraction characterization of the 2-(2,4-difluorophenyl)-1-methylphenylpyridinium hexafluorophosphate and 1-ethyl-2-(2,4-difluorophenyl)phenylpyridinium hexafluorophosphate show an extensive series of Csbnd H⋯F, Csbnd F⋯π and Psbnd F⋯π intermolecular interactions, which give rise to a supramolecular network. The relationship between the solid-state structures and the melting points is discussed by the evaluation of the thermal behavior based on experimental data from Differential Scanning Calorimetry (DSC) studies, and also using the analysis of the ion pairs binding energies. These new compounds based on phenylpyridine allow us to grow the diversity of ionic liquids and their crystalline salts, increasing the knowledge about the chemical and physical properties of these ionic species.

High-efficiency, low-temperature cesium diodes with lanthanum-hexaboride electrodes

NASA Technical Reports Server (NTRS)

Morris, J. F.

1974-01-01

Lanthanum hexaboride electrodes in 1700 K cesium diodes may triple power outputs compared with those demonstrated for nuclear thermionic space applications. Still greater relative gains seem possible for emitters below 1700 K. Further improvements in cesium diode performance should result from the lower collector temperatures allowed for earth and low power space duties. Decreased temperatures will lessen thermal transport losses that attend thermionic conversion mechanisms. Such advantages will add to those from collector Carnot and electrode effects. If plasma ignition difficulties impede diode temperature reductions, recycling small fractions of the output power could provide ionization. So high efficiency, low temperature cesium diodes with lanthanum hexaboride electrodes appear feasible.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Delmau, L.H.; Haverlock, T.J.; Sloop, F.V., Jr.

This report presents the work that followed the CSSX model development completed in FY2002. The developed cesium and potassium extraction model was based on extraction data obtained from simple aqueous media. It was tested to ensure the validity of the prediction for the cesium extraction from actual waste. Compositions of the actual tank waste were obtained from the Savannah River Site personnel and were used to prepare defined simulants and to predict cesium distribution ratios using the model. It was therefore possible to compare the cesium distribution ratios obtained from the actual waste, the simulant, and the predicted values. Itmore » was determined that the predicted values agree with the measured values for the simulants. Predicted values also agreed, with three exceptions, with measured values for the tank wastes. Discrepancies were attributed in part to the uncertainty in the cation/anion balance in the actual waste composition, but likely more so to the uncertainty in the potassium concentration in the waste, given the demonstrated large competing effect of this metal on cesium extraction. It was demonstrated that the upper limit for the potassium concentration in the feed ought to not exceed 0.05 M in order to maintain suitable cesium distribution ratios.« less

Efficiency of fly ash belite cement and zeolite matrices for immobilizing cesium.

PubMed

Goñi, S; Guerrero, A; Lorenzo, M P

2006-10-11

The efficiency of innovative matrices for immobilizing cesium is presented in this work. The matrix formulation included the use of fly ash belite cement (FABC-2-W) and gismondine-type Na-P1 zeolite, both of which are synthesized from fly ash of coal combustion. The efficiency for immobilizing cesium is evaluated from the leaching test ANSI/ANS 16.1-1986 at the temperature of 40 degrees C, from which the apparent diffusion coefficient of cesium is obtained. Matrices with 100% of FABC-2-W are used as a reference. The integrity of matrices is evaluated by porosity and pore-size distribution from mercury intrusion porosimetry, X-ray diffraction and nitrogen adsorption analyses. Both matrices can be classified as good solidify systems for cesium, specially the FABC-2-W/zeolite matrix in which the replacement of 50% of belite cement by the gismondine-type Na-P1 zeolite caused a decrease of two orders of magnitude of cesium mean Effective Diffusion Coefficient (D(e)) (2.8e-09 cm(2)/s versus 2.2e-07 cm(2)/s, for FABC-2-W/zeolite and FABC-2-W matrices, respectively).

Calixarene crown ether solvent composition and use thereof for extraction of cesium from alkaline waste solutions

DOEpatents

Moyer, Bruce A.; Sachleben, Richard A.; Bonnesen, Peter V.; Presley, Derek J.

2001-01-01

A solvent composition and corresponding method for extracting cesium (Cs) from aqueous neutral and alkaline solutions containing Cs and perhaps other competing metal ions is described. The method entails contacting an aqueous Cs-containing solution with a solvent consisting of a specific class of lipophilic calix[4]arene-crown ether extractants dissolved in a hydrocarbon-based diluent containing a specific class of alkyl-aromatic ether alcohols as modifiers. The cesium values are subsequently recovered from the extractant, and the solvent subsequently recycled, by contacting the Cs-containing organic solution with an aqueous stripping solution. This combined extraction and stripping method is especially useful as a process for removal of the radionuclide cesium-137 from highly alkaline waste solutions which are also very concentrated in sodium and potassium. No pre-treatment of the waste solution is necessary, and the cesium can be recovered using a safe and inexpensive stripping process using water, dilute (millimolar) acid solutions, or dilute (millimolar) salt solutions. An important application for this invention would be treatment of alkaline nuclear tank wastes. Alternatively, the invention could be applied to decontamination of acidic reprocessing wastes containing cesium-137.

Congenital hypothyroidism from complete iodide transport defect: long-term evolution with iodide treatment.

PubMed Central

Albero, R.; Cerdan, A.; Sanchez Franco, F.

1987-01-01

Hypothyroidism from iodide transport deficiency is a rare disease, especially when found in two affected siblings. Treatment with high doses of iodide has been recommended, but no long term results have been reported. Two siblings with congenital hypothyroidism due to total failure to transport iodide have been followed up during twelve and a half years of treatment with oral potassium iodide. Iodine doses varied between 10.3 and 22 mg/day, and serum total iodine concentrations between 100 and 210 micrograms/dl. Total triiodothyronine (T3), thyroxine (T4) and free T4 were in the normal range during the time of study. Basal thyroid stimulating hormones (TSH) and maximum TSH response to thyrotrophin releasing hormone (TRH) were also in the range of normal values. These data along with clinical findings confirmed the potential usefulness of iodine in hypothyroidism due to complete iodide transport defect. PMID:3451231

Project Overview: Inhibition of the Sodium-Iodide Symporter by Perchlorate: Evaluation of Lifestage Sensitivity Using PBPK Modeling

EPA Science Inventory

Perchlorate (ClO4-) competitively inhibits uptake of iodide by the sodium-iodide symporter (NIS) in laboratory animals and humans. NIS is found in many tissues, but is primarily responsible for sequestering iodide into the thyroid, enabling biosynthesis of thyroid hormones. The N...

21 CFR 184.1634 - Potassium iodide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Potassium iodide. 184.1634 Section 184.1634 Food... Specific Substances Affirmed as GRAS § 184.1634 Potassium iodide. (a) Potassium iodide (KI, CAS Reg. No. 7681-11-0) is the potassium salt of hydriodic acid. It occurs naturally in sea water and in salt...

21 CFR 184.1634 - Potassium iodide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Potassium iodide. 184.1634 Section 184.1634 Food... Specific Substances Affirmed as GRAS § 184.1634 Potassium iodide. (a) Potassium iodide (KI, CAS Reg. No. 7681-11-0) is the potassium salt of hydriodic acid. It occurs naturally in sea water and in salt...

21 CFR 184.1634 - Potassium iodide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Potassium iodide. 184.1634 Section 184.1634 Food... Specific Substances Affirmed as GRAS § 184.1634 Potassium iodide. (a) Potassium iodide (KI, CAS Reg. No. 7681-11-0) is the potassium salt of hydriodic acid. It occurs naturally in sea water and in salt...

21 CFR 184.1634 - Potassium iodide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium iodide. 184.1634 Section 184.1634 Food... Specific Substances Affirmed as GRAS § 184.1634 Potassium iodide. (a) Potassium iodide (KI, CAS Reg. No. 7681-11-0) is the potassium salt of hydriodic acid. It occurs naturally in sea water and in salt...

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 outputmore » 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) to be incorporated into grout.« less

Dismantling the "Red Wall" of Colloidal Perovskites: Highly Luminescent Formamidinium and Formamidinium-Cesium Lead Iodide Nanocrystals.

PubMed

Protesescu, Loredana; Yakunin, Sergii; Kumar, Sudhir; Bär, Janine; Bertolotti, Federica; Masciocchi, Norberto; Guagliardi, Antonietta; Grotevent, Matthias; Shorubalko, Ivan; Bodnarchuk, Maryna I; Shih, Chih-Jen; Kovalenko, Maksym V

2017-03-28

Colloidal nanocrystals (NCs) of APbX 3 -type lead halide perovskites [A = Cs + , CH 3 NH 3 + (methylammonium or MA + ) or CH(NH 2 ) 2 + (formamidinium or FA + ); X = Cl - , Br - , I - ] have recently emerged as highly versatile photonic sources for applications ranging from simple photoluminescence down-conversion (e.g., for display backlighting) to light-emitting diodes. From the perspective of spectral coverage, a formidable challenge facing the use of these materials is how to obtain stable emissions in the red and infrared spectral regions covered by the iodide-based compositions. So far, red-emissive CsPbI 3 NCs have been shown to suffer from a delayed phase transformation into a nonluminescent, wide-band-gap 1D polymorph, and MAPbI 3 exhibits very limited chemical durability. In this work, we report a facile colloidal synthesis method for obtaining FAPbI 3 and FA-doped CsPbI 3 NCs that are uniform in size (10-15 nm) and nearly cubic in shape and exhibit drastically higher robustness than their MA- or Cs-only cousins with similar sizes and morphologies. Detailed structural analysis indicated that the FAPbI 3 NCs had a cubic crystal structure, while the FA 0.1 Cs 0.9 PbI 3 NCs had a 3D orthorhombic structure that was isostructural to the structure of CsPbBr 3 NCs. Bright photoluminescence (PL) with high quantum yield (QY > 70%) spanning red (690 nm, FA 0.1 Cs 0.9 PbI 3 NCs) and near-infrared (near-IR, ca. 780 nm, FAPbI 3 NCs) regions was sustained for several months or more in both the colloidal state and in films. The peak PL wavelengths can be fine-tuned by using postsynthetic cation- and anion-exchange reactions. Amplified spontaneous emissions with low thresholds of 28 and 7.5 μJ cm -2 were obtained from the films deposited from FA 0.1 Cs 0.9 PbI 3 and FAPbI 3 NCs, respectively. Furthermore, light-emitting diodes with a high external quantum efficiency of 2.3% were obtained by using FAPbI 3 NCs.

Dismantling the “Red Wall” of Colloidal Perovskites: Highly Luminescent Formamidinium and Formamidinium–Cesium Lead Iodide Nanocrystals

PubMed Central

2017-01-01

Colloidal nanocrystals (NCs) of APbX3-type lead halide perovskites [A = Cs+, CH3NH3+ (methylammonium or MA+) or CH(NH2)2+ (formamidinium or FA+); X = Cl–, Br–, I–] have recently emerged as highly versatile photonic sources for applications ranging from simple photoluminescence down-conversion (e.g., for display backlighting) to light-emitting diodes. From the perspective of spectral coverage, a formidable challenge facing the use of these materials is how to obtain stable emissions in the red and infrared spectral regions covered by the iodide-based compositions. So far, red-emissive CsPbI3 NCs have been shown to suffer from a delayed phase transformation into a nonluminescent, wide-band-gap 1D polymorph, and MAPbI3 exhibits very limited chemical durability. In this work, we report a facile colloidal synthesis method for obtaining FAPbI3 and FA-doped CsPbI3 NCs that are uniform in size (10–15 nm) and nearly cubic in shape and exhibit drastically higher robustness than their MA- or Cs-only cousins with similar sizes and morphologies. Detailed structural analysis indicated that the FAPbI3 NCs had a cubic crystal structure, while the FA0.1Cs0.9PbI3 NCs had a 3D orthorhombic structure that was isostructural to the structure of CsPbBr3 NCs. Bright photoluminescence (PL) with high quantum yield (QY > 70%) spanning red (690 nm, FA0.1Cs0.9PbI3 NCs) and near-infrared (near-IR, ca. 780 nm, FAPbI3 NCs) regions was sustained for several months or more in both the colloidal state and in films. The peak PL wavelengths can be fine-tuned by using postsynthetic cation- and anion-exchange reactions. Amplified spontaneous emissions with low thresholds of 28 and 7.5 μJ cm–2 were obtained from the films deposited from FA0.1Cs0.9PbI3 and FAPbI3 NCs, respectively. Furthermore, light-emitting diodes with a high external quantum efficiency of 2.3% were obtained by using FAPbI3 NCs. PMID:28231432

Effects of Excess Fluoride and Iodide on Thyroid Function and Morphology.

PubMed

Jiang, Yaqiu; Guo, Xiujuan; Sun, Qiuyan; Shan, Zhongyan; Teng, Weiping

2016-04-01

Exposure to high levels of iodide in Cangzhou, Shandong Province, China has been associated with increased incidence of thyroid disease; however, whether fluoride can affect the thyroid remains controversial. To investigate the effects of excess fluoride, we evaluated thyroid gland structure and function in rats exposed to fluoride and iodide, either alone or in combination. Five-week-old Wistar rats (n = 160 total) were randomly divided into eight groups: three groups that were given excess fluoride (15, 30, or 60 ppm F); one group given excess iodide (1200 μg/L I); three groups given excess iodide plus fluoride (1200 μg/L I plus 15, 30, or 60 ppm F); and one control group. The serum concentrations of the thyroid hormones TT3 and TT4 on day 150 were significantly reduced for certain fluoride groups; however, no significant differences were observed in concentrations for the pituitary hormone TSH among any groups. Hematoxylin and eosin staining revealed that iodide causes an increase in the areas of the colloid lumens and a decrease in the diameters of epithelial cells and nuclei; however, fluoride causes an increase in nuclear diameters. The damage to follicular epithelial cells upon fluoride or iodide treatment was easily observed by transmission electron microscopy, but the effects were most dramatic upon treatment with both fluoride and iodide. These results suggest that iodide causes the most damage but that fluoride can promote specific changes in the function and morphology of the thyroid, either alone or in combination with iodide.

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

PubMed

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 value<0.05). Iodide ions were entrapped within the aqueous core of w/o microemulsion. 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.

Electrochemical quantification of iodide ions in synthetic urine using silver nanoparticles: a proof-of-concept.

PubMed

Toh, Her Shuang; Tschulik, Kristina; Batchelor-McAuley, Christopher; Compton, Richard G

2014-08-21

Typical urinary iodide concentrations range from 0.3 μM to 6.0 μM. The conventional analytical method is based on the Sandell-Kolthoff reaction. It involves the toxic reagent, arsenic acid, and a waiting time of 30 minutes for the iodide ions to reduce the cerium(iv) ions. In the presented work, an alternative fast electrochemical method based on a silver nanoparticle modified electrode is proposed. Cyclic voltammetry was performed with a freshly modified electrode in presence of iodide ions and the voltammetric peaks corresponding to the oxidation of silver to silver iodide and the reverse reaction were recorded. The peak height of the reduction signal of silver iodide was used to plot a calibration line for the iodide ions. Two calibration plots for the iodide ions were obtained, one in 0.1 M sodium nitrate (a chloride-ion free environment to circumvent any interference from the other halides) and another in synthetic urine (which contains 0.2 M KCl). In both of the calibration plots, linear relationships were found between the reduction peak height and the iodide ion concentration of 0.3 μM to 6.0 μM. A slope of 1.46 × 10(-2) A M(-1) and a R(2) value of 0.999 were obtained for the iodide detection in sodium nitrate. For the synthetic urine experiments, a slope of 3.58 × 10(-3) A M(-1) and a R(2) value of 0.942 were measured. A robust iodide sensor with the potential to be developed into a point-of-care system has been validated.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tseng, F.Y.; Rani, C.S.; Field, J.B.

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.more » 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.« less

Determination of iodide with 1,3-dibromo-5,5-dimethylhydantoin (DBH) in comparison with the ICl-method. Analytical methods of pharmacopeias with DBH in respect to environmental and economical concern. Part 3.

PubMed

Hilp, M; Senjuk, S

2001-06-01

USP 1995 (The United States Pharmacopeia, 23rd Edit., (1995), potassium iodide p. 1265, sodium iodide p. 1424), PH. EUR. 1997 (European Pharmacopoeia, third ed., Council of Europe, Strasbourg, (1997), potassium iodide p. 1367, sodium iodide p. 1493) and JAP 1996 (The Japanes Pharmacopoeia, 13th ed. (1996), potassium iodide p. 578, sodium iodide p. 630) determine iodide with the ICl-method (J. Am. Chem. Soc. 25 (1903) 756-761; Z. Anorg. Chem. 36 (1903) 76-83; Fresenius Z. Anal. Chem. 106 (1936) 12-23; Arzneibuch-Kommentar, Wissenschaftliche Erläuterungen zum Europäischen Arzneibuch, Wissenschaftliche Verlagsgesellschaft mbH, Stuttgart, Govi-Verlag - Pharmazeutischer Verlag GmbH, Eschborn, 12th suppl. (1999), K10 p. 2), using chloroform, which is toxic and hazardous to environment. Without the application of chlorinated hydrocarbons USP 2000 (The United State Pharmacopeia, 24th ed. (2000), potassium iodide p. 1368, sodium iodide p. 1535) and Brit 1999 (British Pharmacopoeia London, (1999), Appendix VIII C, p. A162) titrate iodide with the redox indicator amaranth. A titration with potentiometric indication giving two end-points at the step of I(2) and [ICl(2)](-) is described. Due to the high concentration of hydrochloric acid required for the ICl-method, the determination with DBH (1,3-dibromo-5,5-dimethylhydantoin; 1,3-dibromo-5,5-dimethyl-2,4-imidazolidinedione) can be recommended and is performed easily. Similarly, the iodide content of gallamine triethiodide may be analyzed with DBH by application of a visual two-phase titration in water and ethyl acetate or with potentiometric indication in a mixture of 2-propanol and water. During the removal of the excess of DBH 4-bromo-triethylgallamine (2,2',2"-[1-bromo-benzene-2,3,4-triyltris(oxy)]N,N,N-triethylethanium) is formed.

Removal of bromide and iodide anions from drinking water by silver-activated carbon aerogels.

PubMed

Sánchez-Polo, M; Rivera-Utrilla, J; Salhi, E; von Gunten, U

2006-08-01

The aim of this study is to analyze the use of Ag-doped activated carbon aerogels for bromide and iodide removal from drinking water and to study how the activation of Ag-doped aerogels affects their behavior. It has been observed that the carbonization treatment and activation process of Ag-doped aerogels increased the surface area value ( [Formula: see text] ), whereas the volume of meso-(V(2)) and macropores (V(3)) decreased slightly. Chemical characterization of the materials revealed that carbonization and especially activation process considerably increased the surface basicity of the sample. Original sample (A) presented acidic surface properties (pH(PZC)=4.5) with 21% surface oxygen, whereas the sample that underwent activation showed mainly basic surface chemical properties (pH(PZC)=9.5) with only 6% of surface oxygen. Carbonization and especially, activation process considerable increased the adsorption capacity of bromide and iodide ions. This would mainly be produced by (i) an increase in the microporosity of the sample, which increases Ag-adsorption sites available to halide anions, and (ii) a rise of the basicity of the sample, which produces an increase in attractive electrostatic interactions between the aerogel surface, positively charged at the working pH (pH(solution)

A comparison between the gastric and salivary concentration of iodide, pertechnetate, and bromide in man

PubMed Central

Harden, R. McG.; Alexander, W. D.; Shimmins, J.; Chisholm, D.

1969-01-01

The concentration of iodide (I−) and pertechnetate (TcO4−) and bromide (Br−) has been measured simultaneously in gastric juice and parotid saliva. The combined gastric and salivary clearance for iodide and pertechnetate is more than twice the clearance of these ions by the thyroid gland. The concentration of the ions was in the order I−>TcO4−>Br− in both gastric juice and saliva. Differences exist between the secretion of iodide, pertechnetate, and bromide. Bromide, in contrast to iodide and pertechnetate, was found to be more concentrated in gastric juice than in saliva. The ratio of the iodide to pertechnetate clearance was greater in gastric juice than in saliva. PMID:5358585

Strontium-90 and cesium-137 distribution in Baltic Sea waters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lazarev, L.N.; Gedeonov, L.I.; Ivanova, L.M.

The strontium-90 and cesium-137 concentrations determined in 1983 in the Baltic Sea proper and the Gulf of Finland and in the Soviet Baltic rivers are furnished. The cesium-137 content has been found to be directly proportional to the salinity of the water. Significant influx of technogenic radioactive contaminants from the North to the Baltic Sea was noted in 1983.

Introduction to Quartz Frequency Standards

DTIC Science & Technology

1992-03-01

changes is 5 X 10-"N. Gas permeation under conditions where there is an abnormally high concentration of hydrogen or helium in the atmosphere can lead...Rubidium Life Rubidium depletion Power Buffer gas depletion __________Weight Glass contaminants Cesium Life Cesium supply depletion Power Spent cesium... Tifton , R., Electronic Activity Dip Measurement, IEEE Trans. on Instrumentation and Measurement, Vol. IM-27, pp. 59-65, 1978. 23. Ballato, A., Frequency

Leaching Characteristics of Hanford Ferrocyanide Wastes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, Matthew K.; Fiskum, Sandra K.; Peterson, Reid A.

2009-12-21

A series of leach tests were performed on actual Hanford Site tank wastes in support of the Hanford Tank Waste Treatment and Immobilization Plant (WTP). The samples were targeted composite slurries of high-level tank waste materials representing major complex, radioactive, tank waste mixtures at the Hanford Site. Using a filtration/leaching apparatus, sample solids were concentrated, caustic leached, and washed under conditions representative of those planned for the Pretreatment Facility in the WTP. Caustic leaching was performed to assess the mobilization of aluminum (as gibbsite, Al[OH]3, and boehmite AlO[OH]), phosphates [PO43-], chromium [Cr3+] and, to a lesser extent, oxalates [C2O42-]). Ferrocyanidemore » waste released the solid phase 137Cs during caustic leaching; this was antithetical to the other Hanford waste types studied. Previous testing on ferrocyanide tank waste focused on the aging of the ferrocyanide salt complex and its thermal compatibilities with nitrites and nitrates. Few studies, however, examined cesium mobilization in the waste. Careful consideration should be given to the pretreatment of ferrocyanide wastes in light of this new observed behavior, given the fact that previous testing on simulants indicates a vastly different cesium mobility in this waste form. The discourse of this work will address the overall ferrocyanide leaching characteristics as well as the behavior of the 137Cs during leaching.« less

METHOD FOR THE RECOVERY OF CESIUM VALUES

DOEpatents

Rimshaw, S.J.

1960-02-16

A method is given for recovering Cs/sup 137/ from radioactive waste solutions together with extraneous impurities. Ammonium alum is precipitated in the waste solution. The alum, which carries the cesium, is separated from the supernatant liquid and then dissolved in water. The resulting aqueous solution is then provided with a source of hydroxyl ions, which precipitates aluminum as the hydroxide, and the aluminum hydroxide is separated from the resulting liquid. This liquid, which contains anionic impurities together with ammonium and cesium, is passed through an anion exchange resin bed which removes the anionic impurities. The ammonium in the effluent is removed by destructive distiilation, leaving a substantiaily pure cesium salt in the effluent.

Preparation and use of polymeric materials containing hydrophobic anions and plasticizers for separation of cesium and strontium

DOEpatents

Abney, Kent D.; Kinkead, Scott A.; Mason, Caroline F. V.; Rais, Jiri

1997-01-01

Preparation and use of polymeric materials containing hydrophobic anions and plasticizers for extraction of cesium and strontium. The use of polymeric materials containing plasticizers which are solvents for hydrophobic anions such as derivatives of cobalt dicarbollide or tetraphenylborate which are capable of extracting cesium and strontium ions from aqueous solutions in contact with the polymeric materials, is described. The polymeric material may also include a synergistic agent for a given ion like polyethylene glycol or a crown ether, for removal of radioactive isotopes of cesium and strontium from solutions of diverse composition and, in particular, for solutions containing large excess of sodium nitrate.

Fluoro-alcohol phase modifiers and process for cesium solvent extraction

DOEpatents

Bonnesen, Peter V.; Moyer, Bruce A.; Sachleben, Richard A.

2003-05-20

The invention relates to a class of phenoxy fluoro-alcohols, their preparation, and their use as phase modifiers and solvating agents in a solvent composition for the extraction of cesium from alkaline solutions. These phenoxy fluoro-alcohols comply with the formula: ##STR1## in which n=2 to 4; X represents a hydrogen or a fluorine atom, and R.sup.2 -R.sup.6 are hydrogen or alkyl substituents. These phenoxy fluoro-alcohol phase modifiers are a necessary component to a robust solvent composition and process useful for the removal of radioactive cesium from alkaline nuclear waste streams. The fluoro-alcohols can also be used in solvents designed to extract other cesium from acidic or neutral solutions.

Method for removing cesium from a nuclear reactor coolant

DOEpatents

Colburn, R.P.

1983-08-10

A method of and system for removing cesium from a liquid metal reactor coolant including a carbon packing trap in the primary coolant system for absorbing a major portion of the radioactive cesium from the coolant flowing therethrough at a reduced temperature. A regeneration subloop system having a secondary carbon packing trap is selectively connected to the primary system for isolating the main trap therefrom and connecting it to the regeneration system. Increasing the temperature of the sodium flowing through the primary trap diffuses a portion of the cesium inventory thereof further into the carbon matrix while simultaneously redispersing a portion into the regeneration system for absorption at a reduced temperature by the secondary trap.

Preparation and use of polymeric materials containing hydrophobic anions and plasticizers for separation of cesium and strontium

DOEpatents

Abney, K.D.; Kinkead, S.A.; Mason, C.F.V.; Rais, J.

1997-09-09

Preparation and use is described for polymeric materials containing hydrophobic anions and plasticizers for extraction of cesium and strontium. The use of polymeric materials containing plasticizers which are solvents for hydrophobic anions such as derivatives of cobalt dicarbollide or tetraphenylborate which are capable of extracting cesium and strontium ions from aqueous solutions in contact with the polymeric materials, is described. The polymeric material may also include a synergistic agent for a given ion like polyethylene glycol or a crown ether, for removal of radioactive isotopes of cesium and strontium from solutions of diverse composition and, in particular, for solutions containing large excess of sodium nitrate.

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

PubMed

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.

The BLI-3/TSP-15/DOXA-1 Dual Oxidase Complex Is Required for Iodide Toxicity in Caenorhabditis elegans

PubMed Central

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

2014-01-01

Iodine is an essential trace element for life. Iodide deficiency can lead to defective biosynthesis of thyroid hormones and is a major cause of hypothyroidism and mental retardation. Excess iodide intake, however, has been linked to different thyroidal diseases. How excess iodide causes harmful effects is not well understood. Here, we found that the nematode Caenorhabditis elegans exhibits developmental arrest and other pleiotropic defects when exposed to excess iodide. To identify the responsible genes, we performed a forward genetic screen and isolated 12 mutants that can survive in excess iodide. These mutants define at least four genes, two of which we identified as bli-3 and tsp-15. bli-3 encodes the C. elegans ortholog of the mammalian dual oxidase DUOX1 and tsp-15 encodes the tetraspanin protein TSP-15, which was previously shown to interact with BLI-3. The C. elegans dual oxidase maturation factor DOXA-1 is also required for the arresting effect of excess iodide. Finally, we detected a dramatically increased biogenesis of reactive oxygen species in animals treated with excess iodide, and this effect can be partially suppressed by bli-3 and tsp-15 mutations. We propose that the BLI-3/TSP-15/DOXA-1 dual oxidase complex is required for the toxic pleiotropic effects of excess iodide. PMID:25480962

Uptake mechanism for iodine species to black carbon.

PubMed

Choung, Sungwook; Um, Wooyong; Kim, Minkyung; Kim, Min-Gyu

2013-09-17

Natural organic matter (NOM) plays an important role in determining the fate and transport of iodine species such as iodide (I(-)) and iodate (IO3(-)) in groundwater system. Although NOM exists as diverse forms in environments, prior iodine studies have mainly focused on uptake processes of iodide and iodate to humic materials. This study was conducted to determine the iodide and iodate uptake potential for a particulate NOM (i.e., black carbon [BC]). A laboratory-produced BC and commercial humic acid were used for batch experiments to compare their iodine uptake properties. The BC exhibited >100 times greater uptake capability for iodide than iodate at low pH of ~3, while iodide uptake was negligible for the humic acid. The uptake properties of both solids strongly depend on the initial iodine aqueous concentrations. After uptake reaction of iodide to the BC, X-ray absorption fine structure spectroscopy results indicated that the iodide was converted to electrophilic species, and iodine was covalently bound to carbon atom in polycyclic aromatic hydrocarbons present in the BC. The computed distribution coefficients (i.e., Kd values) suggest that the BC materials retard significantly the transport of iodide at low pH in environmental systems containing even a small amount of BC.

Thermionic converter performance with oxide collectors

NASA Technical Reports Server (NTRS)

Lieb, D.; Goodale, D.; Briere, T.; Balestra, C.

1977-01-01

Thermionic converters using a variety of metal oxide collector surfaces have been fabricated and tested. Both work function and power output data are presented and evaluated. Oxides of barium, strontium, zinc, tungsten and titanium have been incorporated into a variable spacing converter. Tungsten oxide was found to give the highest converter performance and to furnish oxygen for the emitter at the same time. Oxygenated emitters operate at reduced cesium pressure with an increase in electrode spacing. Electron spectroscopy for chemical analysis (ESCA) performed on several tungsten oxide collectors showed cesium penetration of the oxide layer, possibly forming a cesium tungstate bronze. Titanium oxide showed high performance but did not furnish oxygen for the emitter; strontium oxide, in the form of a sprayed layer, appeared to dissociate in the presence of cesium. Sprayed coatings of barium and zinc oxides produced collector work functions of about 1.3 eV, but had excessive series resistance. Lanthanum hexaboride, in combination with oxygen introduced through a silver tube, and cesium produced a low work function collector and better than average performance.

Adsorption characteristics of sol gel-derived zirconia for cesium ions from aqueous solutions.

PubMed

Yakout, Sobhy M; Hassan, Hisham S

2014-07-01

Zirconia powder was synthesized via a sol gel method and placed in a batch reactor for cesium removal investigation. X-ray analysis and Fourier transform infrared spectroscopy were utilized for the evaluation of the developed adsorbent. The adsorption process has been investigated as a function of pH, contact time and temperature. The adsorption is strongly dependent on the pH of the medium whereby the removal efficiency increases as the pH turns to the alkaline range. The process was initially very fast and the maximum adsorption was attained within 60 min of contact. A pseudo-second-order model and homogeneous particle diffusion model (HPDM) were found to be the best to correlate the diffusion of cesium into the zirconia particles. Furthermore, adsorption thermodynamic parameters, namely the standard enthalpy, entropy, and Gibbs free energy, were calculated. The results indicate that cesium adsorption by zirconia is an endothermic (ΔH>0) process and good affinity of cesium ions towards the sorbent (ΔS>0) was observed.

Iodide-ion-induced oscillations of the ferroin-catalyzed Belousov—Zhabotinskii reaction

NASA Astrophysics Data System (ADS)

Melicherčík, Milan; Treindl, Ľudovít

1992-08-01

Contrary to "classical" Belousov—Zhabotinskii (BZ) oscillatory systems, consisting of malonic acid, Ce(IV)—Ce(III) or Mn(III)—Mn(II) redox catalyst and KBrO 3 in solutions of H 2SO 4, where in an interval of added iodide initial concentrations 10 -4 mol dm -3 < [I -] 0 < 10 -3 mol dm -3 the oscillations have the same frequency and amplitude as in the absence of iodide, the effect of added iodide on the ferroin-catalyzed BZ system with methyl ester of 3-oxobutanoic acid leads to an increase in the number of oscillations and in the time of their duration. The dependence of this effect on substrate, bromate, iodide, sulfuric acid and ferroin concentrations has been studied. The observations may be explained by a mechanism involving direct reduction of ferroin by iodide, oxidation of iodide to iodate by bromate with a bromide production and eventual faster bromination and iodination of methyl ester of 3-oxobutanoic acid in relation to malonic acid.

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

DOE PAGES

Adamic, M. L.; Lister, T. E.; Dufek, E. J.; ...

2015-03-25

This paper presents an evaluation of an alternate method for preparing environmental samples for 129I 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. Furthermore, precipitated silver iodide samples are usually mixed with niobium or silver powdermore » 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.« less

Simulating Wet Deposition of Radiocesium from the Chernobyl Accident

DTIC Science & Technology

2001-03-01

In response to the Chernobyl nuclear power plant accident of 1986, a cesium-137 deposition dataset was assembled. Most of the airborne Chernobyl ... Chernobyl cesium-137. A cloud base parameterization modification is tested and appears to slightly improve the accuracy of one HYSPLIT simulation of...daily Chernobyl cesium-137 deposition over the course of the accident at isolated European sites, and degrades the accuracy of another HYSPLIT simulation

Potential of Calendula alata for phytoremediation of stable cesium and lead from solutions.

PubMed

Borghei, Mehdi; Arjmandi, Reza; Moogouei, Roxana

2011-10-01

Calendula alata plants were tested for their potential to remove stable cesium and lead from solutions in a 15-day period. The plants were grown hydroponically and placed in solutions containing CsCl and Pb(C₂H₃O₂)₂ at different concentrations (0.6, 2 and 5 mg l⁻¹). When plants were incubated in CsCl solutions 46.84 ± 2.12%, 41.35 ± 1.59%, and 52.06 ± 1.02% cesium was found to be remediated after 15 days. Moreover, more than 99% lead was removed from the Pb(C₂H₃O₂)₂ solution in all three concentrations after 15 days during the same period. When both CsCl and Pb(C₂H₃O₂)₂ were supplemented together in the solution, 9.92 ± 1.22%, 45.56 ± 3.52%, and 46.16 ± 1.48% cesium and 95.30 ± 0.72%, 96.64 ± 0.30%, and 99.02 ± 0.04% lead were removed after 15 days. The present study suggests that hydroponically grown C. alata could be used as a potential candidate plant for phytoremediation of cesium and lead from solutions; however, plants were found to be more efficient for the remediation of lead than cesium.

Quantifying Atmospheric Fallout of Fukushima-derived Radioactive Isotopes in the Hawaiian Islands

NASA Astrophysics Data System (ADS)

McKenzie, Trista; Dulai, Henrietta

2016-04-01

On March 11, 2011, several reactors at the Fukushima Dai-ichi Nuclear Power Plant suffered damage and released the radioisotopes iodine-131, cesium-134, and cesium-137 into the atmosphere. A week later, these isotopes were detected in aerosols over the state of Hawaii and in milk samples analyzed from the Big Island. Because the detected levels were significantly below levels of health concern, the state did not attempt to quantify the deposition of these nuclides on the islands. This study estimated the magnitude of atmospheric fallout of cesium and iodine, and examined the patterns of cesium wet deposition with precipitation observed in March 2011. Mushroom and soil samples were collected along precipitation gradients on Oahu and the island of Hawaii and analyzed for cesium isotopes using gamma spectrometry. Fukushima-derived fallout was differentiated from historic nuclear weapons testing fallout by the presence of Cs-134, which has a shorter half-life of 2.06 years and the fact that Cs-134 and 137 were released from the severed power plant nearly in parity. We found that Fukushima-derived cesium was present in both mushrooms and soil and the soil inventories ranged 2.2-60.9 Bq/m2 for Cs-137 and 16.1-445.8 Bq/m2 for I-131. Additionally, we found that Fukushima-derived cesium inventories in soils were correlated with precipitation gradients. This research confirmed and quantified the presence of Fukushima-derived fallout in Hawaii, however the activities detected were orders of magnitude lower than fallout associated with the nuclear weapons testing in the Pacific.

An accurate derivation of the air dose-rate and the deposition concentration distribution by aerial monitoring in a low level contaminated area

NASA Astrophysics Data System (ADS)

Nishizawa, Yukiyasu; Sugita, Takeshi; Sanada, Yukihisa; Torii, Tatsuo

2015-04-01

Since 2011, MEXT (Ministry of Education, Culture, Sports, Science and Technology, Japan) have been conducting aerial monitoring to investigate the distribution of radioactive cesium dispersed into the atmosphere after the accident at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), Tokyo Electric Power Company. Distribution maps of the air dose-rate at 1 m above the ground and the radioactive cesium deposition concentration on the ground are prepared using spectrum obtained by aerial monitoring. The radioactive cesium deposition is derived from its dose rate, which is calculated by excluding the dose rate of the background radiation due to natural radionuclides from the air dose-rate at 1 m above the ground. The first step of the current method of calculating the dose rate due to natural radionuclides is calculate the ratio of the total count rate of areas where no radioactive cesium is detected and the count rate of regions with energy levels of 1,400 keV or higher (BG-Index). Next, calculate the air dose rate of radioactive cesium by multiplying the BG-Index and the integrated count rate of 1,400 keV or higher for the area where the radioactive cesium is distributed. In high dose-rate areas, however, the count rate of the 1,365-keV peak of Cs-134, though small, is included in the integrated count rate of 1,400 keV or higher, which could cause an overestimation of the air dose rate of natural radionuclides. We developed a method for accurately evaluating the distribution maps of natural air dose-rate by excluding the effect of radioactive cesium, even in contaminated areas, and obtained the accurate air dose-rate map attributed the radioactive cesium deposition on the ground. Furthermore, the natural dose-rate distribution throughout Japan has been obtained by this method.

Palladium-Catalyzed Direct C–H Arylation of Cyclic Enaminones with Aryl Iodides

PubMed Central

Yu, Yi-Yun; Bi, Lei

2013-01-01

A ligand-free method for the Pd-catalyzed direct arylation of cyclic enaminones using aryl iodides was developed. This method can be applied to a wide range of cyclic enaminones and aryl iodides with excellent C5-regioselectivity. Using widely available aryl iodides, the generality of this transformation provides easy access to a variety of 3-arylpiperidine structural motifs. PMID:23750615

Development of a mercuric iodide solid state spectrometer for X-ray astronomy

NASA Technical Reports Server (NTRS)

Vallerga, J.

1983-01-01

Mercuric iodide detectors, experimental development for astronomical use, X ray observations of the 1980 Cygnus X-1 High State, astronomical had X ray detectors in current use, detector development, balloon flight of large area (1500 sq cm) Phoswich detectors, had X ray telescope design, shielded mercuric iodide background measurement, Monte Carlo analysis, measurements with a shielded mercuric iodide detector are discussed.

Flavonoid Rutin Increases Thyroid Iodide Uptake in Rats

PubMed Central

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

2013-01-01

Thyroid iodide uptake through the sodium-iodide symporter (NIS) is not only an essential step for thyroid hormones biosynthesis, but also fundamental for the diagnosis and treatment of different thyroid diseases. However, part of patients with thyroid cancer is refractory to radioiodine therapy, due to reduced ability to uptake iodide, which greatly reduces the chances of survival. Therefore, compounds able to increase thyroid iodide uptake are of great interest. It has been shown that some flavonoids are able to increase iodide uptake and NIS expression in vitro, however, data in vivo are lacking. Flavonoids are polyhydroxyphenolic compounds, found in vegetables present in human diet, and have been shown not only to modulate NIS, but also thyroperoxidase (TPO), the key enzyme in thyroid hormones biosynthesis, besides having antiproliferative effect in thyroid cancer cell lines. Therefore, we aimed to evaluate the effect of some flavonoids on thyroid iodide uptake in Wistar rats in vivo. Among the flavonoids tested, rutin was the only one able to increase thyroid iodide uptake, so we decided to evaluate the effect of this flavonoid on some aspects of thyroid hormones synthesis and metabolism. Rutin led to a slight reduction of serum T4 and T3 without changes in serum thyrotropin (TSH), and significantly increased hypothalamic, pituitary and brown adipose tissue type 2 deiodinase and decreased liver type 1 deiodinase activities. Moreover, rutin treatment increased thyroid iodide uptake probably due to the increment of NIS expression, which might be secondary to increased response to TSH, since TSH receptor expression was increased. Thus, rutin might be useful as an adjuvant in radioiodine therapy, since this flavonoid increased thyroid iodide uptake without greatly affecting thyroid function. PMID:24023911

Evaluation of perturbations in serum thyroid hormones during human pregnancy due to dietary iodide and perchlorate exposure using a biologically based dose-response model.

PubMed

Lumen, Annie; Mattie, David R; Fisher, Jeffrey W

2013-06-01

A biologically based dose-response model (BBDR) for the hypothalamic pituitary thyroid (HPT) axis was developed in the near-term pregnant mother and fetus. This model was calibrated to predict serum levels of iodide, total thyroxine (T4), free thyroxine (fT4), and total triiodothyronine (T3) in the mother and fetus for a range of dietary iodide intake. The model was extended to describe perchlorate, an environmental and food contaminant, that competes with the sodium iodide symporter protein for thyroidal uptake of iodide. Using this mode-of-action framework, simulations were performed to determine the daily ingestion rates of perchlorate that would be associated with hypothyroxinemia or onset of hypothyroidism for varying iodide intake. Model simulations suggested that a maternal iodide intake of 75 to 250 µg/day and an environmentally relevant exposure of perchlorate (~0.1 µg/kg/day) did not result in hypothyroxinemia or hypothyroidism. For a daily iodide-sufficient intake of 200 µg/day, the dose of perchlorate required to reduce maternal fT4 levels to a hypothyroxinemic state was estimated at 32.2 µg/kg/day. As iodide intake was lowered to 75 µg/day, the model simulated daily perchlorate dose required to cause hypothyroxinemia was reduced by eightfold. Similarly, the perchlorate intake rates associated with the onset of subclinical hypothyroidism ranged from 54.8 to 21.5 µg/kg/day for daily iodide intake of 250-75 µg/day. This BBDR-HPT axis model for pregnancy provides an example of a novel public health assessment tool that may be expanded to address other endocrine-active chemicals found in food and the environment.

10 CFR Appendix B to Part 30 - Quantities 1 of Licensed Material Requiring Labeling

Code of Federal Regulations, 2012 CFR

2012-01-01

... Iodine-126 1 Iodine-129 0.1 Iodine-131 1 Iodine-132 10 Iodine-133 1 Iodine-134 10 Iodine-135 10 Iridium... Arsenic-73 100 Arsenic-74 10 Arsenic-76 10 Arsenic-77 100 Barium-131 10 Barium-133 10 Barium-140 10... Carbon-14 100 Cerium-141 100 Cerium-143 100 Cerium-144 1 Cesium-131 1,000 Cesium-134m 100 Cesium-134 1...

10 CFR Appendix B to Part 30 - Quantities 1 of Licensed Material Requiring Labeling

Code of Federal Regulations, 2014 CFR

2014-01-01

... Iodine-126 1 Iodine-129 0.1 Iodine-131 1 Iodine-132 10 Iodine-133 1 Iodine-134 10 Iodine-135 10 Iridium... Arsenic-73 100 Arsenic-74 10 Arsenic-76 10 Arsenic-77 100 Barium-131 10 Barium-133 10 Barium-140 10... Carbon-14 100 Cerium-141 100 Cerium-143 100 Cerium-144 1 Cesium-131 1,000 Cesium-134m 100 Cesium-134 1...

10 CFR Appendix B to Part 30 - Quantities 1 of Licensed Material Requiring Labeling

Code of Federal Regulations, 2013 CFR

2013-01-01

... Iodine-126 1 Iodine-129 0.1 Iodine-131 1 Iodine-132 10 Iodine-133 1 Iodine-134 10 Iodine-135 10 Iridium... Arsenic-73 100 Arsenic-74 10 Arsenic-76 10 Arsenic-77 100 Barium-131 10 Barium-133 10 Barium-140 10... Carbon-14 100 Cerium-141 100 Cerium-143 100 Cerium-144 1 Cesium-131 1,000 Cesium-134m 100 Cesium-134 1...

Cesium Platinide Hydride 4Cs 2 Pt-CsH: An Intermetallic Double Salt Featuring Metal Anions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smetana, Volodymyr; Mudring, Anja-Verena

2016-10-24

With Cs9Pt4H a new representative of ionic compounds featuring metal anions can be added to this rare-membered family. Cs 9Pt 4H exhibits a complex crystal structure containing Cs + cations, Pt 2- and H - anions. Being a red, transparent compound its band gap is in the visible range of the electromagnetic spectrum and the ionic type of bonding is confirmed by quantum chemical calculations. This cesium platinide hydride can formally be considered as a double salt of the “alloy” cesium–platinum, or better cesium platinide, Cs2Pt, and the salt cesium hydride CsH according to Cs 9Pt 4H≡4 Cs 2Pt∙CsH.

Fabrication and surface characterization of composite refractory compounds suitable for thermionic converters

NASA Technical Reports Server (NTRS)

Davis, P. R.; Swanson, L. W.

1980-01-01

Thermal faceting was observed for the high index planes of LaB6. The (100), (110), and (111) planes were found to be the most thermodynamically stable faces in vacuum in a study of electrode materials for thermionic emitters. The properties of adsorbed carbon, cesium, and cesium-oxygen layers were investigated on LaB6 single crystal surfaces as well as on Zr/0/W(100) and W(100). Cesium was found to increase electron reflection near the collision threshold on LaB6(100) and W(100) and to decrease the reflection on Zr/0/W(100). This difference may be explained by the unusually high threshold reflection coefficient of Zr/0/W without adsorbed cesium.

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

PubMed

Dorman, James W; Steinberg, Spencer M

2010-02-01

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

Controllable deposition of regular lead iodide nanoplatelets and their photoluminescence at room temperature

NASA Astrophysics Data System (ADS)

Kong, Weimin; Li, Guohui; Liang, Qiangbing; Ji, Xingqi; Li, Gang; Ji, Ting; Che, Tao; Hao, Yuying; Cui, Yanxia

2018-03-01

In this work, the synthesis of regular single crystalline lead iodide nanoplatelets are carried out based on the physical vapor phase deposition method. Different lead iodide nanoplatelets are obtained by tuning the location of the mica substrate along with the temperature of the tube furnace. The rules of size, thickness, density of the lead iodide nanoplatelets at varied deposition conditions are analyzed according to the crystal growth principles. It was claimed in literature that the photoluminescence of lead iodide could be obtained only at a low temperature (lower than 200 K). Here, at room temperature, we successfully obtained the photoluminescence spectra of the prepared lead iodide nanoplatelets, which possess two apparent peaks due to the biexcitons and the inelastic scattering of excitons, respectively. Our present study contributes to the development of nanoscaled high performance optoelectronic devices.

Growth and luminescent properties of Ce and Eu doped Cesium Hafnium Iodide single crystalline scintillators

NASA Astrophysics Data System (ADS)

Kodama, Shohei; Kurosawa, Shunsuke; Yamaji, Akihiro; Pejchal, Jan; Král, Robert; Ohashi, Yuji; Kamada, Kei; Yokota, Yuui; Nikl, Martin; Yoshikawa, Akira

2018-06-01

In order to obtain new scintillators with high light output and high effective atomic number (Zeff), we performed anion-substitution for Cs2HfCl6 (CHC) scintillator, and then, we succeeded in growing Cs2HfI6 (CHI) single crystalline scintillator. It had Zeff of 58, which is the same as that of CHC, and had high light output of ∼70,000 photons/MeV with 700 nm emission. However, its scintillation decay time of ∼2.5 μs was slow for practical use as gamma-ray monitor. In this study, we performed Ce3+/Eu2+ doping to Hf4+ site to improve decay time of CHI, introducing the fast 5d-4f luminescence. Ce:CHI and Eu:CHI single crystals were finally obtained by the vertical Bridgman-Stockbarger method. The luminescence spectra of the Ce:CHI and Eu:CHI were very similar to that of the non-doped CHI, which would mean that no 5d-4f luminescence of Ce3+/Eu2+ was observed. The measured light output and decay time of Ce:CHI were ∼48,000 photon/MeV and 2.3 ± 0.1 μs, respectively. As for Eu:CHI, light output and decay time were ∼69,000 photon/MeV and 2.8 ± 0.1 μs, respectively.

Characterization of PbWO4 crystals for high-energy physics experiments

NASA Astrophysics Data System (ADS)

Kim, M. J.; Park, H.; Kim, H. J.

2016-09-01

High-energy physics (HEP) experiments have employed many new types of scintillators. Specifically, bismuth germanate, thallium-doped cesium iodide, and lead tungstate (PbWO4, PWO) have been used for the L3 experiment; CLEO II, Belle and BES-III; and CMS, respectively. PWO has particularly beneficial properties, such as high density, fast decay time, short radiation length and radiation hardness. In this study, we tested the PWO crystals at low temperatures to determine their applicability in future calorimeters. Various crystals from the Proton Antiproton Annihilations at Darmstadt (PANDA) experiment in Giessen, the Bogoroditsk Techno-Chemical Plant (BTCP) in Russia and by Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS) in China were investigated. We studied the scintillation properties of PWO crystals, such as their X-ray luminescence, relative light yields, absolute light yields, energy resolutions, decay times and longitudinal uniformities of their light yields. In addition, we measured the temperature dependences of the light yields and decay times by using a 137Cs γ-ray source. The emission spectra of the PWO crystals consisted of a broad band from 350 nm to 700 nm, and the peak emission wavelength in each spectrum was 420 nm. The emission spectra of the PWO crystals from SICCAS were slightly shifted to longer wavelengths compared with those of the crystals from the other institutions.

Amide-Catalyzed Phase-Selective Crystallization Reduces Defect Density in Wide-Bandgap Perovskites.

PubMed

Kim, Junghwan; Saidaminov, Makhsud I; Tan, Hairen; Zhao, Yicheng; Kim, Younghoon; Choi, Jongmin; Jo, Jea Woong; Fan, James; Quintero-Bermudez, Rafael; Yang, Zhenyu; Quan, Li Na; Wei, Mingyang; Voznyy, Oleksandr; Sargent, Edward H

2018-03-01

Wide-bandgap (WBG) formamidinium-cesium (FA-Cs) lead iodide-bromide mixed perovskites are promising materials for front cells well-matched with crystalline silicon to form tandem solar cells. They offer avenues to augment the performance of widely deployed commercial solar cells. However, phase instability, high open-circuit voltage (V oc ) deficit, and large hysteresis limit this otherwise promising technology. Here, by controlling the crystallization of FA-Cs WBG perovskite with the aid of a formamide cosolvent, light-induced phase segregation and hysteresis in perovskite solar cells are suppressed. The highly polar solvent additive formamide induces direct formation of the black perovskite phase, bypassing the yellow phases, thereby reducing the density of defects in films. As a result, the optimized WBG perovskite solar cells (PSCs) (E g ≈ 1.75 eV) exhibit a high V oc of 1.23 V, reduced hysteresis, and a power conversion efficiency (PCE) of 17.8%. A PCE of 15.2% on 1.1 cm 2 solar cells, the highest among the reported efficiencies for large-area PSCs having this bandgap is also demonstrated. These perovskites show excellent phase stability and thermal stability, as well as long-term air stability. They maintain ≈95% of their initial PCE after 1300 h of storage in dry air without encapsulation. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Identification of Potential Sodium Iodide Symporter (NIS) Inhibitors in ToxCast Phase1_v2 Chemical Library Using in vitro Radioactive Iodide Uptake (RAIU) Assay

EPA Science Inventory

Identification of Potential Sodium Iodide Symporter (NIS) Inhibitors in ToxCast Phase1_v2 Chemical Library Using in vitro Radioactive Iodide Uptake (RAIU) Assay Jun Wang1,2, Daniel R. Hallinger2, Ashley S. Murr2, Angela R. Buckalew1, Tammy E. Stoker2, Susan C. Laws21Oak Ridge In...

Lanthanide doped strontium-barium cesium halide scintillators

DOEpatents

Bizarri, Gregory; Bourret-Courchesne, Edith; Derenzo, Stephen E.; Borade, Ramesh B.; Gundiah, Gautam; Yan, Zewu; Hanrahan, Stephen M.; Chaudhry, Anurag; Canning, Andrew

2015-06-09

The present invention provides for a composition comprising an inorganic scintillator comprising an optionally lanthanide-doped strontium-barium, optionally cesium, halide, useful for detecting nuclear material.

Alloying n-Butylamine into CsPbBr3 to Give a Two-Dimensional Bilayered Perovskite Ferroelectric Material.

PubMed

Wu, Zhenyue; Ji, Chengmin; Li, Lina; Kong, Jintao; Sun, Zhihua; Zhao, Sangen; Wang, Sasa; Hong, Maochun; Luo, Junhua

2018-05-11

Cesium-lead halide perovskites (e.g. CsPbBr 3 ) have gained attention because of their rich physical properties, but their bulk ferroelectricity remains unexplored. Herein, by alloying flexible organic cations into the cubic CsPbBr 3 , we design the first cesium-based two-dimensional (2D) perovskite ferroelectric material with both inorganic alkali metal and organic cations, (C 4 H 9 NH 3 ) 2 CsPb 2 Br 7 (1). Strikingly, 1 shows a high Curie temperature (T c =412 K) above that of BaTiO 3 (ca. 393 K) and notable spontaneous polarization (ca. 4.2 μC cm -2 ), triggered by not only the ordering of organic cations but also atomic displacement of inorganic Cs + ions. To our knowledge, such a 2D bilayered Cs + -based metal-halide perovskite ferroelectric material with inorganic and organic cations is unprecedented. 1 also shows photoelectric semiconducting behavior with large "on/off" ratios of photoconductivity (>10 3 ). © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

An Efficient Process for Pd-Catalyzed C–N Cross-Coupling Reactions of Aryl Iodides: Insight Into Controlling Factors

PubMed Central

Fors, Brett P.; Davis, Nicole R.; Buchwald, Stephen L.

2009-01-01

An investigation into Pd-catalyzed C–N cross-coupling reactions of aryl iodides is described. NaI is shown to have a significant inhibitory effect on these processes. By switching to a solvent system in which the iodide byproduct was insoluble, reactions of aryl iodides were accomplished with the same efficiencies as aryl chlorides and bromides. Using catalyst systems based on certain biarylphosphine ligands, aryl iodides were successfully reacted with an array of primary and secondary amines in high yields. Lastly, reactions of heteroarylamines and heteroaryliodides were also conducted in high yields. PMID:19348431

Human responses to the threat of or exposure to ionizing radiation at Three Mile Island, Pennsylvania, and Goiania, Brazil.

PubMed

Collins, Daniel L

2002-02-01

The psychological stressors and their aftereffects associated with the Three Mile Island accident, the Goiania, Brazil, cesium-137 accident, and the Abadia, Brazil, storage location are summarized and compared. Cross-cultural comparisons of human responses to ionizing radiation are rare. A multidisciplinary methodological approach to examining the psychological responses to ionizing radiation is even more rare. The psychological, behavioral, neuroendocrine, and cardiovascular results are summarized for Three Mile Island, Goiania, and Abadia.

Potassium Iodide

MedlinePlus

... iodide you should take or give to your child depends on your age or your child's age. If potassium iodide is taken by a ... you should take yourself or give to your child. Ask your doctor, pharmacist, or public official if ...

Comparison of two novel in-syringe dispersive liquid-liquid microextraction techniques for the determination of iodide in water samples using spectrophotometry.

PubMed

Kaykhaii, Massoud; Sargazi, Mona

2014-01-01

Two new, rapid methodologies have been developed and applied successfully for the determination of trace levels of iodide in real water samples. Both techniques are based on a combination of in-syringe dispersive liquid-liquid microextraction (IS-DLLME) and micro-volume UV-Vis spectrophotometry. In the first technique, iodide is oxidized with nitrous acid to the colorless anion of ICl2(-) at high concentration of hydrochloric acid. Rhodamine B is added and by means of one step IS-DLLME, the ion-pair formed was extracted into toluene and measured spectrophotometrically. Acetone is used as dispersive solvent. The second method is based on the IS-DLLME microextraction of iodide as iodide/1, 10-phenanthroline-iron((II)) chelate cation ion-pair (colored) into nitrobenzene. Methanol was selected as dispersive solvent. Optimal conditions for iodide extraction were determined for both approaches. Methods are compared in terms of analytical parameters such as precision, accuracy, speed and limit of detection. Both methods were successfully applied to determining iodide in tap and river water samples. Copyright © 2013 Elsevier B.V. All rights reserved.

Transfer of radio-cesium from forest soil to woodchips using fungal activities

NASA Astrophysics Data System (ADS)

Kaneko, Nobuhiro; Huang, Yao; Tanaka, Yoichiro; Fujiwara, Yoshihiro; Sasaki, Michiko; Toda, Hiroto; Takahashi, Terumasa; Kobayashi, Tatsuaki; Harada, Naoki; Nonaka, Masahiro

2014-05-01

Raido-cesium released to terrestrial ecosystems by nuclear accidents is know to accumulate forest soil and organic layer on the soil. Forests in Japan are not exceptions. Practically it is impossible to decontaminate large area of forests. However, there is a strong demand from local people, who has been using secondary forests (Satoyama) around croplands in hilly areas, to decontaminate radio-cesium, because those people used to collect wild mushrooms and edible plants, and there are active cultures of mushrooms using logs and sawdusts. These natural resource uses consist substantial part of their economical activities, Therefore it is needed to decontaminate some selected part of forests in Japan to local economy. Clear cutting and scraping surface soil and organic matter are common methods of decontamination. However the efficiency of decontamination is up to 30% reduction of aerial radiation, and the cost to preserve contaminated debris is not affordable. In this study we used wood chips as a growth media for saprotrophic fungi which are known to accumulate redio-cesium. There are many studies indicated that mushrooms accumulated redio-cesium from forest soil and organic layer. It is not practical to collect mushrooms to decontaminate redio-cesium, because biomass of mushrooms are not enough to collect total contaminants. Mushrooms are only minor part of saprotrophic fungi. Fungal biomass in forest soil is about 1% of dead organic matter on forest floor. Our previous study to observe Cs accumulation to decomposing leaf litter indicated 18% absorption of total soil radio-Cs to litter during one year field incubation (Kaneko et al., 2013), and Cs concentration was proportional to fungal biomass on litter. This result indicated that fungi transferred radio-cesium around newly supplied leaf litter free of contamination. Therefore effective decontamination will be possible if we can provide large amount of growth media for saprotrophic fungi, and the media can be removed from forests with fungal bodies. We covered forest floor using wood chips, and observed Cs accumulation, and found that up to 50% of soil radio-cesium was transferred from soil to wood chips after 6-month of field incubation. Therefore this method is effective to decontaminate forest using ecological process. Kaneko N, Huang Y, Nakamori T, Tanaka Y, Nonaka M. Radio-cesium accumulation during decomposition of leaf litter in a deciduous forest after the Fukushima NPP accident. Geophysical Research Abstracts. 2013;15(EGU2013):7809.

Sericitization of illite decreases sorption capabilities for cesium

NASA Astrophysics Data System (ADS)

Choung, S.; Hwang, J.; Han, W.; Shin, W.

2017-12-01

Release of radioactive cesium (137Cs) to environment occurs through nuclear accidents such as Chernobyl and Fukushima. The concern is that 137Cs has long half-life (t1/2 = 30.2 years) with chemical toxicity and γ-radiation. Sorption techniques are mainly applied to remove 137Cs from aquatic environment. In particular, it has been known well that clay minerals (e.g, illite) are effective and economical sorbents for 137Cs. Illite that was formed by hydrothermal alteration exist with sericite through "sericitization" processes. Although sericite has analogous composition and lattice structure with illite, the sorptive characteristics of illite and sericite for radiocesium could be different. This study evaluated the effects of hydrothermal alteration and weathering process on illite cesium sorption properties. Natural illite samples were collected at Yeongdong area in Korea as the world-largest hydrothermal deposits for illite. The samples were analyzed by XRF, XRD and SEM-EDX to determine mineralogy, chemical compositions and morphological characteristics, and used for batch sorption experiments. The Yeongdong illites predominantly consist of illite, sericite, quartz, and albite. The measured cesium sorption distribution coefficients (Kd,Cs) of reference illite and sericite were approximately 6000 and 400 L kg-1 at low aqueous concentration (Cw 10-7 M), respectively. In contrast, Kd,Cs values for the Yeongdong illite samples ranged from 500 to 4000 L kg-1 at identical concentration. The observed narrow and sharp XRD peak of sericite indicated that the sericite has better crystallinity compared to illite. These experimental results suggested that sericitization processes of illite can decline the sorption capabilities of illite for cesium under various hydrothermal conditions. In particular, weathering experiments raised the cesium sorption to illite, which seems to be related to the increase of preferential sorption sites for cesium through crystallinity destruction (i.e., frayed edge sites).

Research on the treatment of liquid waste containing cesium by an adsorption-microfiltration process with potassium zinc hexacyanoferrate.

PubMed

Zhang, Chang-Ping; Gu, Ping; Zhao, Jun; Zhang, Dong; Deng, Yue

2009-08-15

The removal of cesium from an aqueous solution by an adsorption-microfiltration (AMF) process was investigated in jar tests and lab-scale tests. The adsorbent was K(2)Zn(3)[Fe(CN)(6)](2). The obtained cesium data in the jar test fit a Freundlich-type isotherm well. In the lab-scale test, the mean cesium concentration of the raw water and the effluent were 106.87 microg/L and 0.59 microg/L, respectively, the mean removal of cesium was 99.44%, and the mean decontamination factors (DF) and concentration factors (CF) were 208 and 539, respectively. The removal of cesium in the lab-scale test was better than that in the jar test because the old adsorbents remaining in the reactor still had adsorption capacity with the premise of no significant desorption being observed, and the continuous renewal of the adsorbent surface improved the adsorption capacity of the adsorbent. Some of the suspended solids were deposited on the bottom of the reactor, which would affect the mixing of adsorbents with the raw water and the renewing of the adsorbent surface. Membrane fouling was the main physical fouling mechanism, and the cake layer was the main filtration resistance. Specific flux (SF) decreased step by step during the whole period of operation due to membrane fouling and concentration polarization. The quality of the effluent was good and the turbidity remained lower than 0.1NTU, and the toxic anion, CN(-), could not be detected because of its low concentration, this indicated that the effluent was safe. The AMF process was feasible for practical application in the treatment of liquid waste containing cesium.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Garrett N.; Russell, Renee L.; Peterson, Reid A.

This report summarizes the work performed to evaluate multiple, cesium loading, and elution cycles for small columns containing SRF resin using a simple, high-level waste (HLW) simulant. Cesium ion exchange loading and elution curves were generated for a nominal 5 M Na, 2.4E-05 M Cs, 0.115 M Al loading solution traced with 134Cs followed by elution with variable HNO3 (0.02, 0.07, 0.15, 0.23, and 0.28 M) containing variable CsNO3 (5.0E-09, 5.0E-08, and 5.0E-07 M) and traced with 137Cs. The ion exchange system consisted of a pump, tubing, process solutions, and a single, small ({approx}15.7 mL) bed of SRF resin withmore » a water-jacketed column for temperature-control. The columns were loaded with approximately 250 bed volumes (BVs) of feed solution at 45 C and at 1.5 to 12 BV per hour (0.15 to 1.2 cm/min). The columns were then eluted with 29+ BVs of HNO3 processed at 25 C and at 1.4 BV/h. The two independent tracers allowed analysis of the on-column cesium interaction between the loading and elution solutions. The objective of these tests was to improve the correlation between the spent resin cesium content and cesium leached out of the resin in subsequent loading cycles (cesium leakage) to help establish acid strength and purity requirements.« less

Adsorption of Radioactive Cesium to Illite-Sericite Mixed Clays

NASA Astrophysics Data System (ADS)

Hwang, J. H.; Choung, S.; Park, C. S.; Jeon, S.; Han, J. H.; Han, W. S.

2016-12-01

Once radioactive cesium is released into aquatic environments through nuclear accidents such as Chernobyl and Fukushima, it is harmful to human and ecological system for a long time (t1/2 = 30.2 years) because of its chemical toxicity and γ-radiation. Sorption mechanism is mainly applied to remove the cesium from aquatic environments. Illite is one of effective sorbent, considering economical cost for remediation. Although natural illite is typically produced as a mixture with sericite formed by phyllic alteration in hydrothermal ore deposits, the effects of illite-sericite mixed clays on cesium sorption was rarely studied. This study evaluated the sorption properties of cesium to natural illite collected at Yeongdong in Korea as the world-largest illite producing areas (termed "Yeongdong illite"). The illite samples were analyzed by XRF, XRD, FT-IR and SEM-EDX to determine mineralogy, chemical composition, and morphological characteristics, and used for batch sorption experiments. Most of "Yeongdong illite" samples predominantly consist of sericite, quartz, albite, plagioclase feldspar and with minor illite. Cesium sorption distribution coefficients (Kd,Cs) of various "Yeongdong illite" samples ranged from 500 to 4000 L/kg at low aqueous concentration (Cw 10-7 M). Considering Kd,Cs values were 400 and 6000 using reference sericite and illite materials, respectively, in this study, these results suggested that high contents of sericite significantly affect the decrease of sorption capabilities for radiocesium by natural illite (i.e., illite-sericite mixed clay).

Laboratory-Scale Column Testing Using IONSIV IE-911 for Removing Cesium from Acidic Tank Waste Simulant. 2: Determination of Cesium Exchange Capacity and Effective Mass Transfer Coefficient from a 500-cm3 Column Experiement

DOE Office of Scientific and Technical Information (OSTI.GOV)

T.J. Tranter; R.D. Tillotson; T.A. Todd

2005-04-01

A semi-scale column test was performed using a commercial form of crystalline silicotitanate (CST) for removing radio-cesium from a surrogate acidic tank solution, which represents liquid waste stored at the Idaho National Engineering and Environmental Laboratory (INEEL). The engineered form of CST ion exchanger, known as IONSIVtmIE-911 (UOP, Mt. Laurel,NJ, USA), was tested in a 500-cm3 column to obtain a cesium breakthrough curve. The cesium exchange capacity of this column matched that obtained from previous testing with a 15-mc3 column. A numerical algorithm using implicit finite difference approximations was developed to solve the governing mass transport equations for the CSTmore » columns. An effective mass transfer coefficient was derived from solving these equations for previously reported 15 cm3 tests. The effective mass transfer coefficient was then used to predict the cesium breakthrough curve for the 500-cm3 column and compared to the experimental data reported in this paper. The calculated breakthrough curve showed excellent agreement with the data from the 500-cm3 column even though the interstitial velocity was a factor of two greater. Thus, this approach should provide a reasonable method for scale up to larger columns for treating actual tank waste.« less

IODIDE DEFICIENCY, THYROID HORMONES, AND NEURODEVELOPMENT

EPA Science Inventory

ABSTRACT BODY: Iodide is an essential nutrient for thyroid hormone synthesis. Severe iodide insufficiency during early development is associated with cognitive deficits. Environmental contaminants can perturb the thyroid axis and this perturbation may be more acute under conditio...

New iodide-based molten salt systems for high temperature molten salt batteries

NASA Astrophysics Data System (ADS)

Fujiwara, Syozo; Kato, Fumio; Watanabe, Syouichiro; Inaba, Minoru; Tasaka, Akimasa

Novel multi-component molten salt systems containing iodides, LiF-LiBr-LiI, LiF-NaBr-LiI, and LiF-LiCl-LiBr-LiI, were investigated for use as electrolytes in high temperature molten salt batteries to improve the discharge rate-capability. The iodide-based molten salts showed higher ionic conductivity (∼3 S cm -1 at 500 °C) than conventional LiCl-KCl, and had low enough melting points (below 400 °C) that can be used in practical high temperature molten salt batteries. The iodide-based salts showed instability at temperatures higher than 280 °C in dried air. The decomposition mechanism of iodide-based molten salts was discussed, and it was found that elimination of oxygen from the environment is effective to stabilize the iodide-based molten salts at high temperatures.

Barium iodide and strontium iodide crystals andd scintillators implementing the same

DOEpatents

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.

Radioactive Sediment Transport on Ogaki Dam Reservoir in Fukushima Evacuated Zone: Numerical Simulation Studies by 2-D River Simulation Code

NASA Astrophysics Data System (ADS)

Yamada, Susumu; Kitamura, Akihiro; Kurikami, Hiroshi; Machida, Masahiko

2015-04-01

Fukushima Daiichi Nuclear Power Plant (FDNPP) accident on March 2011 released significant quantities of radionuclides to atmosphere. The most significant nuclide is radioactive cesium isotopes. Therefore, the movement of the cesium is one of the critical issues for the environmental assessment. Since the cesium is strongly sorbed by soil particles, the cesium transport can be regarded as the sediment transport which is mainly brought about by the aquatic system such as a river and a lake. In this research, our target is the sediment transport on Ogaki dam reservoir which is located in about 16 km northwest from FDNPP. The reservoir is one of the principal irrigation dam reservoirs in Fukushima Prefecture and its upstream river basin was heavily contaminated by radioactivity. We simulate the sediment transport on the reservoir using 2-D river simulation code named Nays2D originally developed by Shimizu et al. (The latest version of Nays2D is available as a code included in iRIC (http://i-ric.org/en/), which is a river flow and riverbed variation analysis software package). In general, a 2-D simulation code requires a huge amount of calculation time. Therefore, we parallelize the code and execute it on a parallel computer. We examine the relationship between the behavior of the sediment transport and the height of the reservoir exit. The simulation result shows that almost all the sand that enter into the reservoir deposit close to the entrance of the reservoir for any height of the exit. The amounts of silt depositing within the reservoir slightly increase by raising the height of the exit. However, that of the clay dramatically increases. Especially, more than half of the clay deposits, if the exit is sufficiently high. These results demonstrate that the water level of the reservoir has a strong influence on the amount of the clay discharged from the reservoir. As a result, we conclude that the tuning of the water level has a possibility for controlling the recontamination to the downstream.

Sensitized and heavy atom induced production of acenaphthylene triplet: A laser flash photolysis study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samanta, A.; Fessenden, R.W.

1989-07-27

The triplet state of acenaphthylene has been examined by nanosecond laser flash photolysis using sensitization and heavy atom perturbation techniques. Although acenaphthylene does not form any observable triplet upon direct flash excitation, a transient with microsecond lifetime ({lambda}{sub max} = 315 nm) is observable when a solution of the sample is excited by sensitizers (benzophenone, thioxanthone, benzil). This transient is ascribed to the triplet of acenaphthylene on the basis of its quenching behavior toward oxygen, ferrocene, azulene, and {beta}-carotene. Quantitative data concerning the triplet-triplet absorption and quenching constants are presented. The triplet energy is estimated to lie between 46 andmore » 47 kcal/mol. The triplet can also be produced by direct excitation in solvents containing heavy atoms (ethyl bromide, ethyl iodide). The triplet yield is found to increase with an increase of the amount of the heavy atom containing solvent. No saturation limit is obtained. These facts together with the effect of heavy atoms on the T{sub 1} {yields} S{sub 0} process allow the differing behavior of ethyl bromide and ethyl iodide on the photodimerization process of acenaphthylene to be explained. Triplet-state parameters (extinction coefficient and triplet yield) have been estimated in these solvents by the energy-transfer technique and actinometry.« less

Thermal expansion of silver iodide-silver molybdate glasses at low temperatures

NASA Astrophysics Data System (ADS)

Mandanici, A.; Raimondo, A.; Cutroni, M.; Ramos, M. A.; Rodrigo, J. G.; Vieira, S.; Armellini, C.; Rocca, F.

2009-05-01

Ionic glasses obtained combining silver iodide and silver molybdate are characterized by quite low values of the glass transition temperature Tg around 320-350 K, by high values of the dc ionic conductivity even at room temperature and by a peculiar behavior of the mechanical response at ultrasonic frequencies. In fact, at temperatures well below their glass transition temperature, these glasses exhibit an intense peak of acoustic attenuation well described by two different and almost overlapping relaxational contributions. Considering also that negative thermal expansion has been reported for some molybdate crystalline compounds, we have investigated in this work the thermal expansion of two silver iodomolybdate glasses (AgI)1-x(Ag2MoO4)x for x =0.25 and x =0.33 in a wide temperature range (4.2-300 K) from cryogenic temperatures up to some 20 K below Tg using a precision capacitance dilatometer aiming to understand whether the expansivity shows some possible fingerprint corresponding to the above-mentioned mechanical response. Two different measuring methods, a quasiadiabatic and a continuous one, have been used for the thermal expansion measurements. The results are discussed in comparison with the information obtained from previous investigations based on the extended x-ray absorption fine structure (EXAFS) technique and with the behavior of other ionic glasses.

A fluorescence turn-on sensor for iodide based on a thymine-Hg(II)-thymine complex.

PubMed

Ma, Boling; Zeng, Fang; Zheng, Fangyuan; Wu, Shuizhu

2011-12-23

Iodide plays a vital role in many biological processes, including neurological activity and thyroid function. Due to its physiological relevance, a method for the rapid, sensitive, and selective detection of iodide in food, pharmaceutical products, and biological samples such as urine is of great importance. Herein, we demonstrate a novel and facile strategy for constructing a fluorescence turn-on sensor for iodide based on a T-Hg(II)-T complex (T=thymine). A fluorescent anthracene-thymine dyad (An-T) was synthesized, the binding of which to a mercury(II) ion lead to the formation of a An-T-Hg(II)-T-An complex, thereby quenching the fluorescent emission of this dyad. In this respect, the dyad An-T constituted a fluorescence turn-off sensor for mercury(II) ions in aqueous media. More importantly, it was found that upon addition of iodide, the mercury(II) ion was extracted from the complex due to the even stronger binding between mercury(II) ions and iodide, leading to the release of the free dyad and restoration of the fluorescence. By virtue of this fluorescence quenching and recovery process, the An-T-Hg(II)-T-An complex constitutes a fluorescence turn-on sensor for iodide with a detection limit of 126 nM. Moreover, this sensor is highly selective for iodide over other common anions, and can be used in the determination of iodide in drinking water and biological samples such as urine. This strategy may provide a new approach for sensing some other anions. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

PubMed

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.

RECOVERY OF CESIUM FROM WASTE SOLUTIONS

DOEpatents

Burgus, W.H.

1959-06-30

This patent covers the precipitation of fission products including cesium on nickel or ferric ferrocyanide and subsequent selective dissolution from the carrier with a solution of ammonia or mercurlc nitrate.

Transport of the radioisotopes iodine-131, cesium-134, and cesium-137 from the fallout following the accident at the Chernobyl nuclear reactor into cheesemaking products.

PubMed

Assimakopoulos, P A; Ioannides, K G; Pakou, A A; Papadopoulou, C V; Paradopoulou, C V

1987-07-01

The transport of radiation contamination from milk to products of the cheese making process has been studied. The concentration of radioactive iodine and cesium in samples of sheep milk and cheese (Gruyère) products was measured for 10 consecutive production d. Milk with concentration 100 Bq/L in each of the radionuclides 131I, 134Cs, and 137Cs cheese with concentration 82.2 +/- 3.9 Bq/kg in iodine and an average of 42.3 +/- 2.3 Bq/kg in the cesium isotopes is produced. The corresponding concentrations in cream extracted from the same milk are 26.7 +/- 2.8 Bq/kg (131I) and 18.6 +/- 1.9 Bq/kg (134Cs, 137Cs).

Optical properties and surface morphology studies of palladium contacts on mercuric iodide single crystals

NASA Astrophysics Data System (ADS)

George, M. A.; Azoulay, M.; Burger, A.; Biao, Y.; Silberman, E.; Nason, D.

1993-04-01

Palladium is chemically suitable for electric contacts on mercuric iodide detectors for photon and nuclear radiation detection, so the understanding of palladium contacts is important for fundamental and practical scientific purposes. A study has been conducted on the surface morphology of evaporated contacts using atomic force microscopy (AFM) and optical transmission and reflection. Evaporated palladium coatings are typically nonuniform and may deposit selectively on mercuric iodide surface defects. Reflection measurements show that coating thickness and surface treatment affect intensity, position, and shape of a reflected peak characteristic of the mercuric iodide structure. Results indicate that the band gap energy in the surface of the mercuric iodide is lowered by palladium contacts.

In Vivo Evaluation of Transdermal Iodide Microemulsion for Treating Iodine Deficiency Using Sprague Dawley Rats.

PubMed

Alayoubi, Alaadin; Sullivan, Ryan D; Lou, Hao; Patel, Hemlata; Mandrell, Timothy; Helms, Richard; Almoazen, Hassan

2016-06-01

The objective of this study was to evaluate the transdermal efficiency of iodide microemulsion in treating iodine deficiency using rats as an animal model. Animals were fed either iodine-deficient diet (20 μg/kg iodide) or control diet (200 μg/kg iodide) over a 17-month period. At month 14, iodide microemulsion was applied topically in iodine-deficient group and physiological evaluations of thyroid gland functions were characterized by monitoring the thyroid hormones (T3, T4), thyroid-stimulating hormone (TSH), iodide ion excretion in urine, and the overall rat body weights in both groups. Moreover, morphological evaluations of thyroid gland before and after treatment were performed by ultrasound imaging and through histological assessment. Prior to microemulsion treatment, the levels of T3, T4, and TSH in iodine-deficient group were statistically significant as compared to that in the control group. The levels of T3 and T4 increased while TSH level decreased significantly in iodine-deficient group within the first 4 weeks of treatment. After treatment, iodide concentration in urine increased significantly. There was no statistical difference in weight between the two groups. Ultrasound imaging and histological evaluations showed evidence of hyperplasia in iodine-deficient group. Topical iodide microemulsion has shown a promising potential as a novel delivery system to treat iodine deficiency.

Perchlorate and iodide in whole blood samples from infants, children, and adults in Nanchang, China.

PubMed

Zhang, Tao; Wu, Qian; Sun, Hong Wen; Rao, Jia; Kannan, Kurunthachalam

2010-09-15

Perchlorate, ClO(4)(-), interferes with iodide (I(-)) uptake by the sodium-iodide symporter (NIS) and thereby affects thyroid hormone production in the body. Studies have reported human exposures to perchlorate based on measurements in urine, but little is known about the levels in blood. In this study, we determined concentrations of perchlorate, iodide, and other anions (e.g., chlorate [ClO(3)(-)], bromate [BrO(3)(-)], bromide [Br(-)]) in 131 whole blood samples collected from Chinese donors aged 0.4 to 90 yr, in Nanchang, China. Perchlorate, iodide, and bromide were detected in all of the samples analyzed, whereas chlorate was found in only 27% of the samples and bromate was found in only 2%. The mean (range) concentrations of perchlorate, iodide, and bromide were 2.68 (0.51-10.5), 42.6 (1.58-812), and 2120 (1050-4850) ng/mL, respectively. Perchlorate levels in blood from Nanchang adults were 10-fold greater than levels that have been previously reported for U.S. adults. The iodide/perchlorate molar ratio ranged from 3.05 to 15.3 for all age groups, and the ratio increased with age (r = 0.732, p < 0.01). Perchlorate and bromide concentrations decreased significantly with age, whereas iodide concentrations increased with age. No significant gender-related differences in blood perchlorate, iodide, or bromide levels were found. A significant negative correlation was found between the concentrations of perchlorate and iodide in blood. Exposure doses of perchlorate were estimated for infants, toddlers, children, adolescents, and adults based on the measured concentrations in blood, using a simple pharmacokinetic model. The mean exposure doses of perchlorate for our age groups ranged from 1.12 (adults) to 2.22 μg/kg bw/day (infants), values higher than the United States Environmental Protection Agency's (USEPA) reference dose (RfD: 0.7 μg/kg bw/day). This is the first study on perchlorate and iodide levels in whole blood from infants, toddlers, children, adolescents, and adults from a city in China with known high perchlorate levels.

RADIATION SOURCES

DOEpatents

Brucer, M.H.

1958-04-15

A novel long-lived source of gamma radiation especially suitable for calibration purposes is described. The source of gamma radiation is denoted mock iodine131, which comprises a naixture of barium-133 and cesium-137. The barium and cesium are present in a barium-cesium ratio of approximately 5.7/1 to 14/1, uniformly dispersed in an ion exchange resin and a filter surrounding the resin comprised of a material of atomic number below approximately 51, and substantially 0.7 to 0.9 millimeter thick.

The uptake and elimination of cesium-137 by a grasshopper-romalea microptera

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crossley, Jr, D A; Pryor, M E

1960-10-01

Adults of Romalea microptera, the eastern lubber grasshopper, were fed cesium-137 in bean plants to investigate uptake and elimination of this isotope. A biological half-life of 4 to 5 days was obtained. In experiments where grasshoppers were allowed to feed repeatedly on cesium-contaminated food, the biological half-life was used to pretend Cs 137 was concentrated in muscular tissue, but some was also found in the digestive tract and reproductive organs. Only trace amounts were found in the exoskeleton.

Preliminary Three-Dimensional Simulation of Sediment and Cesium Transport in the Ogi Dam Reservoir using FLESCOT – Task 6, Subtask 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onishi, Yasuo; Kurikami, Hiroshi; Yokuda, Satoru T.

2014-03-28

After the accident at the Fukushima Daiichi Nuclear Power Plant in March 2011, the Japan Atomic Energy Agency and the Pacific Northwest National Laboratory initiated a collaborative project on environmental restoration. In October 2013, the collaborative team started a task of three-dimensional modeling of sediment and cesium transport in the Fukushima environment using the FLESCOT (Flow, Energy, Salinity, Sediment Contaminant Transport) code. As the first trial, we applied it to the Ogi Dam Reservoir that is one of the reservoirs in the Japan Atomic Energy Agency’s (JAEA’s) investigation project. Three simulation cases under the following different temperature conditions were studied:more » • incoming rivers and the Ogi Dam Reservoir have the same water temperature • incoming rivers have lower water temperature than that of the reservoir • incoming rivers have higher water temperature than that of the reservoir. The preliminary simulations suggest that seasonal temperature changes influence the sediment and cesium transport. The preliminary results showed the following: • Suspended sand, and cesium adsorbed by sand, coming into the reservoirs from upstream rivers is deposited near the reservoir entrance. • Suspended silt, and cesium adsorbed by silt, is deposited farther in the reservoir. • Suspended clay, and cesium adsorbed by clay, travels the farthest into the reservoir. With sufficient time, the dissolved cesium reaches the downstream end of the reservoir. This preliminary modeling also suggests the possibility of a suitable dam operation to control the cesium migration farther downstream from the dam. JAEA has been sampling in the Ogi Dam Reservoir, but these data were not yet available for the current model calibration and validation for this reservoir. Nonetheless these preliminary FLESCOT modeling results were qualitatively valid and confirmed the applicability of the FLESCOT code to the Ogi Dam Reservoir, and in general to other reservoirs in the Fukushima environment. The issues to be addressed in future are the following: • Validate the simulation results by comparison with the investigation data. • Confirm the applicability of the FLESCOT code to Fukushima coastal areas. • Increase computation speed by parallelizing the FLESCOT code.« less

A perchlorate sensitive iodide transporter in frogs

PubMed Central

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

2008-01-01

Nucleotide sequence comparisons have identified a gene product in the genome database of African clawed frogs (Xenopus laevis) as a probable member of the solute carrier family of membrane transporters. To confirm its identity as a putative iodide transporter, we examined the function of this sequence after heterologous expression in mammalian cells. A green monkey kidney cell line transfected with the Xenopus nucleotide sequence had significantly greater 125I uptake than sham-transfected control cells. The uptake in carrier-transfected cells was significantly inhibited in the presence of perchlorate, a competitive inhibitor of mammalian Na+/iodide symporter. Tissue distributions of the sequence were also consistent with a role in iodide uptake. The mRNA encoding the carrier was found to be expressed in the thyroid gland, stomach, and kidney of tadpoles from X. laevis, as well as the bullfrog Rana catesbeiana. The ovaries of adult X. laevis also were found to express the carrier. Phylogenetic analysis suggested that the putative X. laevis iodide transporter is orthologous to vertebrate Na+-dependent iodide symporters. We conclude that the amphibian sequence encodes a protein that is indeed a functional Na+/iodide symporter in Xenopus laevis, as well as Rana catesbeiana. PMID:18275962

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

PubMed

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.

A Selective Iodide Ion Sensor Electrode Based on Functionalized ZnO Nanotubes

PubMed Central

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

2013-01-01

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. PMID:23385412

21 CFR 172.375 - Potassium iodide.

Code of Federal Regulations, 2010 CFR

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...

Iron-catalyzed 1,2-addition of perfluoroalkyl iodides to alkynes and alkenes.

PubMed

Xu, Tao; Cheung, Chi Wai; Hu, Xile

2014-05-05

Iron catalysis has been developed for the intermolecular 1,2-addition of perfluoroalkyl iodides to alkynes and alkenes. The catalysis has a wide substrate scope and high functional-group tolerance. A variety of perfluoroalkyl iodides including CF3 I can be employed. The resulting perfluoroalkylated alkyl and alkenyl iodides can be further functionalized by cross-coupling reactions. This methodology provides a straightforward and streamlined access to perfluoroalkylated organic molecules. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Palladium-catalyzed Heck-type cross-couplings of unactivated alkyl iodides.

PubMed

McMahon, Caitlin M; Alexanian, Erik J

2014-06-02

A palladium-catalyzed, intermolecular Heck-type coupling of alkyl iodides and alkenes is described. This process is successful with a variety of primary and secondary unactivated alkyl iodides as reaction partners, including those with hydrogen atoms in the β position. The mild catalytic conditions enable intermolecular C-C bond formations with a diverse set of alkyl iodides and alkenes, including substrates containing base- or nucleophile-sensitive functionality. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Study of radiatively sustained cesium plasmas for solar energy conversion

NASA Technical Reports Server (NTRS)

Palmer, A. J.; Dunning, G. J.

1980-01-01

The results of a study aimed at developing a high temperature solar electric converter are reported. The converter concept is based on the use of an alkali plasma to serve as both an efficient high temperature collector of solar radiation as well as the working fluid for a high temperature working cycle. The working cycle is a simple magnetohydrodynamic (MHD) Rankine cycle employing a solid electrode Faraday MHD channel. Research milestones include the construction of a theoretical model for coupling sunlight in a cesium plasma and the experimental demonstration of cesium plasma heating with a solar simulator in excellent agreement with the theory. Analysis of a solar MHD working cycle in which excimer laser power rather than electric power is extracted is also presented. The analysis predicts a positive gain coefficient on the cesium-xenon excimer laser transition.

Radionuclides in Foods

PubMed Central

Bird, P. M.

1966-01-01

Levels of strontium-90 and cesium-137 in Canadian milk during the period 1960-64 were consistently higher than those in the United States or the United Kingdom, but levels in humans, while also higher, did not reflect the differences observed in milk. Annual dose rates of 27 millirads to bone and 4 millirads to the whole body correspond to the highest average concentrations of strontium-90 and cesium-137 so far observed. Levels of cesium-137 in the urine of residents of the Canadian North were found to increase with the increasing consumption of caribou or reindeer. Whole body counting of a few northern residents showed cesium-137 levels as high as 1000 nanocuries. It is concluded that protective actions are not needed but that studies in the North should be emphasized to provide a better basis for evaluating that particular situation. PMID:5948368

Removal of cesium from simulated liquid waste with countercurrent two-stage adsorption followed by microfiltration.

PubMed

Han, Fei; Zhang, Guang-Hui; Gu, Ping

2012-07-30

Copper ferrocyanide (CuFC) was used as an adsorbent to remove cesium. Jar test results showed that the adsorption capacity of CuFC was better than that of potassium zinc hexacyanoferrate. Lab-scale tests were performed by an adsorption-microfiltration process, and the mean decontamination factor (DF) was 463 when the initial cesium concentration was 101.3μg/L, the dosage of CuFC was 40mg/L and the adsorption time was 20min. The cesium concentration in the effluent continuously decreased with the operation time, which indicated that the used adsorbent retained its adsorption capacity. To use this capacity, experiments on a countercurrent two-stage adsorption (CTA)-microfiltration (MF) process were carried out with CuFC adsorption combined with membrane separation. A calculation method for determining the cesium concentration in the effluent was given, and batch tests in a pressure cup were performed to verify the calculated method. The results showed that the experimental values fitted well with the calculated values in the CTA-MF process. The mean DF was 1123 when the dilution factor was 0.4, the initial cesium concentration was 98.75μg/L and the dosage of CuFC and adsorption time were the same as those used in the lab-scale test. The DF obtained by CTA-MF process was more than three times higher than the single-stage adsorption in the jar test. Copyright © 2012 Elsevier B.V. All rights reserved.

EXAMINATION OF Zr AND Ti RECOMBINER LOOP SPECIMENS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rittenhouse, P.L.

1958-12-19

Cold-worked specimens of iodide zirconium, Zircaloy-2, iodide titanium, and A-55 titanium were tested in a high-pressure recombiner loop in an attempt to duplicate anomalous results obtained in a prior recombiner loop. Hydrogen analyses and metallographic examinations were made on all specimens. The titanium materials and Zircaloy-2 picked up major amounts of hydrogen in the cell section. None of the materials tested showed appreciable hydrogen absorption in the recombiner section. Complete recrystallization occurred in all cell specimens while only Zircaloy-2, of the recombiner specimens, showed any degree of recrystallization. No explanation for this behavior can be given. A survnnary of themore » data obtained in previous recombiner loops is compared with the results of this loop. Conclusions were based on the results of three recombiner loops. Primarlly because of the hydrogen absorption data obtained in all three recombiner loops it is recommended that the zirconium and titunium materials tested not be used in environments similar to those encountered in high pressure recombiner loops. (auth)« less

Polarization and Dielectric Study of Methylammonium Lead Iodide Thin Film to Reveal its Nonferroelectric Nature under Solar Cell Operating Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoque, Md Nadim Ferdous; Yang, Mengjin; Li, Zhen

2016-07-08

Researchers have debated whether methylammonium lead iodide (MAPbI3), with a perovskite crystal structure, is ferroelectric and therefore contributes to the current--voltage hysteresis commonly observed in hybrid perovskite solar cells (PSCs). We thoroughly investigated temperature-dependent polarization, dielectric, and impedance spectroscopies, and we found no evidence of ferroelectric effect in a MAPbI3 thin film at normal operating conditions. Therefore, the effect does not contribute to the hysteresis in PSCs, whereas the large component of ionic migration observed may play a critical role. Our temperature-based polarization and dielectric studies find that MAPbI3 exhibits different electrical behaviors below and above ca. 45 degrees C,more » suggesting a phase transition around this temperature. In particular, we report the activation energies of ionic migration for the two phases and temperature-dependent permittivity of MAPbI3. This study contributes to the understanding of the material properties and device performance of hybrid perovskites.« less

21 CFR 582.5634 - Potassium iodide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5634 Potassium iodide. (a) Product. Potassium iodide. (b) Tolerance. 0.01 percent. (c... salt as a source of dietary iodine in accordance with good manufacturing or feeding practice. ...

21 CFR 582.5634 - Potassium iodide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5634 Potassium iodide. (a) Product. Potassium iodide. (b) Tolerance. 0.01 percent. (c... salt as a source of dietary iodine in accordance with good manufacturing or feeding practice. ...

21 CFR 582.5634 - Potassium iodide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5634 Potassium iodide. (a) Product. Potassium iodide. (b) Tolerance. 0.01 percent. (c... salt as a source of dietary iodine in accordance with good manufacturing or feeding practice. ...

21 CFR 172.375 - Potassium iodide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (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 safely used in accordance with the...

An iodine supplementation of tomato fruits coated with an edible film of the iodide-doped chitosan.

PubMed

Limchoowong, Nunticha; Sricharoen, Phitchan; Techawongstien, Suchila; Chanthai, Saksit

2016-06-01

In general, the risk of numerous thyroid cancers inevitably increases among people with iodine deficiencies. An iodide-doped chitosan (CT-I) solution was prepared for dipping tomatoes to coat the fresh surface with an edible film (1.5 μm), thereby providing iodine-rich fruits for daily intake. Characterisation of the thin film was conducted by FTIR and SEM. Stability of the CT-I film was studied via water immersion at various time intervals, and no residual iodide leached out due to intrinsic interactions between the cationic amino group of chitosan and iodide ions. Moreover, the iodide supplement exhibited no effect on the antioxidant activity of tomatoes. The iodine content in the film-coated tomato was determined by ICP-OES. The tomato coating with 1.5% (w/v) CT-I contained approximately 0.4 μg iodide per gram fresh weight. In addition, the freshness and storability of iodine-doped tomatoes were also maintained for shelf-life concerns. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

PubMed

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

2017-03-15

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

Phase 1 Methyl Iodide Deep-Bed Adsorption Tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soelberg, Nick; Watson, Tony

2014-08-22

Nuclear fission results in the production of fission products (FPs) and activation products including iodine-129, which could evolve into used fuel reprocessing facility off-gas systems, and could require off-gas control to limit air emissions to levels within acceptable emission limits. Research, demonstrations, and some reprocessing plant experience have indicated that diatomic iodine can be captured with efficiencies high enough to meet regulatory requirements. Research on the capture of organic iodides has also been performed, but to a lesser extent [Jubin 2012b]. Several questions remain open regarding the capture of iodine bound in organic compounds. Deep-bed methyl iodide adsorption testing hasmore » progressed according to a multi-laboratory methyl iodide adsorption test plan. This report summarizes the first phase of methyl iodide adsorption work performed according to this test plan using the deep-bed iodine adsorption test system at the Idaho National Laboratory (INL), performed during Fiscal Year (FY) 2013 and early FY-2014. Testing has been performed to address questions posed in the test plan, and followed the testing outline in the test plan. Tests established detection limits, developed procedures for sample analysis with minimal analytical interferences, and confirmed earlier results that show that the methyl iodide reacts when in contact with the AgZ sorbent, and not significantly in the gas flow upstream of the sorbent. The reaction(s) enable separation of the iodine from the organic moiety, so that the iodine can chemisorb onto the sorbent. The organic moiety can form other compounds, some of which are organic compounds that are detected and can be tentatively identified using GC-FID and GCMS. Test results also show that other gas constituents (NOx and/or H2O) can affect the methyl iodide reactions. With NOx and H2O present in the gas stream, the majority of uncaptured iodine exiting iodine-laden sorbent beds is in the form of I2 or HI, species that are soluble in NaOH scrubbing solution for iodine analysis. But when NOx and H2O are not present, then the majority of the uncaptured iodine exiting iodine-laden sorbent is in the form of methyl iodide. Methyl iodide adsorption efficiencies have been high enough so that initial DFs exceed 1,000 to 10,000. The methyl iodide mass transfer zone depths are estimated at 4-8 inches, possibly deeper than mass transfer zone depths estimated for I2 adsorption on AgZ. Additional deep-bed testing and analyses are recommended to (a) expand the data base for methyl iodide adsorption under various conditions specified in the methyl iodide test plan, and (b) provide more data for evaluating organic iodide reactions and reaction byproducts for different potential adsorption conditions.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamilton, T F

Rongelap Atoll experienced close-in ''local fallout'' from nuclear weapons tests conducted by the United States (1946-58) in the northern Marshall Islands. Most of the radiation dose delivered to Rongelap Island residents during the 1950s was from radioactive elements that quickly decayed into non-radioactive elements. Since 1985, the Lawrence Livermore National Laboratory (LLNL) has continued to provide monitoring of radioactive elements from bomb testing in the terrestrial and marine environment of Rongelap Atoll. The only remaining radioactive elements of environmental importance at the atoll are radioactive cesium (cesium-137), radioactive strontium (strontium-90), different types (isotopes) of plutonium, and americium (americium-241). Cesium- 137more » and strontium-90 dissolve in seawater and are continually flushed out of the lagoon into the open ocean. The small amount of residual radioactivity from nuclear weapons tests remaining in the lagoon does not concentrate through the marine food chain. Elevated levels of cesium-137 and strontium-90 are still present in island soils and pose a potential health risk if certain types of local plants and coconut crabs are eaten in large quantities. Cesium-137 is taken up from the soil into plants and edible food products, and may end up in the body of people living on the islands and consuming local food. The presence of cesium-137 in the human body can be detected using a device called a whole body counter. A person relaxes in a chair for a few minutes while counts or measurements are taken using a detector a few inches away from the body. The whole body counting program on Rongelap Island was established in 1999 under a cooperative agreement between the Rongelap Atoll Local Government (RALG), the Republic of the Marshall Islands and the U.S. Department of Energy (DOE). Local technicians from Rongelap continue to operate the facility under supervision of scientists from LLNL. The facility permits resettlement workers living on Rongelap Island to check the amount of cesium-137 in their bodies. The amount of cesium-137 detected in resettlement workers living on Rongelap Island over the past three years is well below the level of radiation exposure considered safe by the Nuclear Claims Tribunal. Returning residents and visitors to Rongelap will also be able to receive a whole body count free of charge to check the level of cesium in their bodies. There is also a very low health risk from exposure to external sources of radiation from visiting or walking around any of the islands on the atoll.« less

The role of the IRE1 pathway in excessive iodide- and/or fluoride-induced apoptosis in Nthy-ori 3-1 cells in vitro.

PubMed

Liu, Hongliang; Zeng, Qiang; Cui, Yushan; Zhao, Liang; Zhang, Lei; Fu, Gang; Hou, Changchun; Zhang, Shun; Yu, Linyu; Jiang, Chunyang; Wang, Zhenglun; Chen, Xuemin; Wang, Aiguo

2014-01-30

Excessive iodide and fluoride coexist in the groundwater in many regions, causing a potential risk to the human thyroid. To investigate the mechanism of iodide- and fluoride-induced thyroid cytotoxicity, human thyroid follicular epithelial cells (Nthy-ori 3-1) were treated with different concentrations of potassium iodide (KI), with or without sodium fluoride (NaF). Cell morphology, viability, lactate dehydrogenase (LDH) leakage, apoptosis, and expression of inositol-requiring enzyme 1 (IRE1) pathway-related molecules were assessed. Results showed 50 mM of KI, 1 mM of NaF, and 50 mM of KI +1 mM of NaF changed cellular morphology, decreased viability, and increased LDH leakage and apoptosis. Elevated expression of binding protein (BiP), IRE1, and C/EBP homologous protein (CHOP) mRNA and protein, as well as spliced X-box-binding protein-1 (sXBP-1) mRNA, were observed in the 1 mM NaF and 50 mM KI +1 mM NaF groups. Collectively, excessive iodide and/or fluoride is cytotoxic to the human thyroid. Although these data do not manifest iodide could induce the IRE1 pathway, the cytotoxicity followed by exposure to fluoride alone or in combination with iodide may be related to IRE1 pathway-induced apoptosis. Furthermore, exposure to the combination of excessive iodide and fluoride may cause interactive effects on thyroid cytotoxicity. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Correlation of Electrode Kinetics with Surface Structure.

DTIC Science & Technology

1980-09-01

platinum and gold electrodes is sufficiently strong so that monolayers are formed upon contact even with small (millimolar) bulk iodide concentrations...transition-metal reactants, we have monitored the effects of altering the electrode material from mercury to silver, platinum, and gold upon the...strikingly different behavior for the reduction of Co III(NH3)5X and Co II(en)2X2 at platinum and gold electrodes. 1 0 For halide bridging ligands (X

Translations on USSR Science and Technology Biomedical and Behavioral Sciences No. 36.

DTIC Science & Technology

1978-07-18

Government Publications issued by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. Indexes to this report (by...AChE against inhibition by fluostigmine. The best protective index had N-rnethyl-4-[y-pyridyl]-pyndi- nium iodide. 1. Introduction The treatment of...and their protective effect on AChE against inhibition by fluostigmine are shown in Table 2. The best protective index was obtained with compounds

Bentonite-Clay Waste Form for the Immobilization of Cesium and Strontium from Fuel Processing Waste Streams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaminski, Michael D.; Mertz, Carol J.

2016-01-01

The physical properties of a surrogate waste form containing cesium, strontium, rubidium, and barium sintered into bentonite clay were evaluated for several simulant feed streams: chlorinated cobalt dicarbollide/polyethylene glycol (CCD-PEG) strip solution, nitrate salt, and chloride salt feeds. We sintered bentonite clay samples with a loading of 30 mass% of cesium, strontium, rubidium, and barium to a density of approximately 3 g/cm 3. Sintering temperatures of up to 1000°C did not result in volatility of cesium. Instead, there was an increase in crystallinity of the waste form upon sintering to 1000ºC for chloride- and nitrate-salt loaded clays. The nitrate saltmore » feed produced various cesium pollucite phases, while the chloride salt feed did not produce these familiar phases. In fact, many of the x-ray diffraction peaks could not be matched to known phases. Assemblages of silicates were formed that incorporated the Sr, Rb, and Ba ions. Gas evolution during sintering to 1000°C was significant (35% weight loss for the CCD-PEG waste-loaded clay), with significant water being evolved at approximately 600°C.« less

Distribution of radioactive cesium in edible parts of cattle.

PubMed

Okada, Keiji; Sato, Itaru; Deguchi, Yoshitaka; Morita, Shigeru; Yasue, Takeshi; Yayota, Masato; Takeda, Ken-Ichi; Sato, Shusuke

2013-12-01

After the disastrous incident of the Fukushima Daiichi Nuclear Power Station, various agricultural, livestock and fishery products have been inspected for radioactive contamination with cesium in Japan. In this study, radioactive cesium was measured in various edible parts of cattle to verify the current inspection method for cattle, in which the neck tissues are generally used as samples. Radioactive cesium concentration in the short plate, diaphragm, liver, lung, omasum, abomasum and small intestine were lower and sirloin, tenderloin, top round meat and tongue were higher than that in the neck. There was no significant difference between the other organs (heart, kidney, lumen and reticulum) and the neck. Ninety-five percent upper tolerance limits of the relative concentration to the neck were 1.88 for sirloin, 1.74 for tenderloin, 1.87 for top round and 1.45 for tongue. These results suggest that a safety factor of 2 is recommended for the radioactivity inspection of cattle to prevent a marketing of meat with higher cesium than the legal limit. Re-inspection should be conducted using another part of muscle, for example, top round, when suspicious levels of 50-100 Bq/kg are detected in the neck. © 2013 Japanese Society of Animal Science.

Rocksalt or cesium chloride: Investigating the relative stability of the cesium halide structures with random phase approximation based methods

NASA Astrophysics Data System (ADS)

Nepal, Niraj K.; Ruzsinszky, Adrienn; Bates, Jefferson E.

2018-03-01

The ground state structural and energetic properties for rocksalt and cesium chloride phases of the cesium halides were explored using the random phase approximation (RPA) and beyond-RPA methods to benchmark the nonempirical SCAN meta-GGA and its empirical dispersion corrections. The importance of nonadditivity and higher-order multipole moments of dispersion in these systems is discussed. RPA generally predicts the equilibrium volume for these halides within 2.4% of the experimental value, while beyond-RPA methods utilizing the renormalized adiabatic LDA (rALDA) exchange-correlation kernel are typically within 1.8%. The zero-point vibrational energy is small and shows that the stability of these halides is purely due to electronic correlation effects. The rAPBE kernel as a correction to RPA overestimates the equilibrium volume and could not predict the correct phase ordering in the case of cesium chloride, while the rALDA kernel consistently predicted results in agreement with the experiment for all of the halides. However, due to its reasonable accuracy with lower computational cost, SCAN+rVV10 proved to be a good alternative to the RPA-like methods for describing the properties of these ionic solids.

Dose-Response Analysis of Developmental Iodide Deficiency: Reductions in Thyroid Hormones and Impaired Hippocampal Synaptic Transmission

EPA Science Inventory

Iodide is an essential nutrient for thyroid hormone synthesis and severe iodide deficiency (ID) during early development is associated with neurological impairments. Several environmental contaminants can perturb the thyroid axis and this perturbation may be more acute under cond...

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

NASA Technical Reports Server (NTRS)

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.

Development of the Next-Generation Caustic-Side Solvent Extraction (NG-CSSX) Process for Cesium Removal from High-Level Tank Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moyer, Bruce A; Bonnesen, Peter V; Delmau, Laetitia Helene

2011-01-01

This paper describes the chemical performance of the Next-Generation Caustic-Side Solvent Extraction (NG-CSSX) process in its current state of development for removal of cesium from the alkaline high-level tank wastes at the Savannah River Site (SRS) in the US Department of Energy (USDOE) complex. Overall, motivation for seeking a major enhancement in performance for the currently deployed CSSX process stems from needs for accelerating the cleanup schedule and reducing the cost of salt-waste disposition. The primary target of the NG-CSSX development campaign in the past year has been to formulate a solvent system and to design a corresponding flowsheet thatmore » boosts the performance of the SRS Modular CSSX Unit (MCU) from a current minimum decontamination factor of 12 to 40,000. The chemical approach entails use of a more soluble calixarene-crown ether, called MaxCalix, allowing the attainment of much higher cesium distribution ratios (DCs) on extraction. Concurrently decreasing the Cs-7SB modifier concentration is anticipated to promote better hydraulics. A new stripping chemistry has been devised using a vitrification-friendly aqueous boric acid strip solution and a guanidine suppressor in the solvent, resulting in sharply decreased DCs on stripping. Results are reported herein on solvent phase behavior and batch Cs distribution for waste simulants and real waste together with a preliminary flowsheet applicable for implementation in the MCU. The new solvent will enable MCU to process a much wider range of salt feeds and thereby extend its service lifetime beyond its design life of three years. Other potential benefits of NG-CSSX include increased throughput of the SRS Salt Waste Processing Facility (SWPF), currently under construction, and an alternative modular near-tank application at Hanford.« less

Influence of methyl and propyl groups on the vibrational spectra of two imidazolium ionic liquids and their non-ionic precursors

NASA Astrophysics Data System (ADS)

Haddad, Boumediene; Mokhtar, Drai; Goussem, Mimanne; Belarbi, El-habib; Villemin, Didier; Bresson, Serge; Rahmouni, Mustapha; Dhumal, Nilesh R.; Kim, Hyung J.; Kiefer, Johannes

2017-04-01

Imidazolium-based ionic liquids (ILs) are usually synthesized using non-ionic imidazole compounds as precursors. While the ILs have been extensively studied in the past, the precursors was not paid much attention to. The structural analysis of the precursors, however, may offer an opportunity to better understand the behavior of the ionic compounds of interest. In this paper, a comparative study of two ionic liquids and their imidazole precursors is presented. The precursors 1-methylimidazole [1-MIM] and 1,2-dimethylimidazole [1,2-DMIM] are compared in order to explain the influences of the methyl group at the C(2) position (methylation). Since the imidazole compounds are non-ionic, the spectroscopic properties of [1-MIM] and [1,2-DMIM] are not affected by cation-anion interactions. In addition, the products obtained by alkylation using propyl iodide leading to the corresponding IL compounds 1-methyl-3-propylimidazolium iodide [1-MPrIM+][I-] and 1,2-dimethyl-3-propylimidazolium iodide [1,2-DMPrIM+][I-] were studied. For this purpose, vibrational spectroscopy in terms of FT-Raman and FTIR in the wavenumber range from [45 to 3500 cm-1] and from [600 to 4000 cm-1], respectively, was performed. Moreover, to aid the spectral assignment, density functional theory (DFT) calculations were carried out. The aim was to investigate the vibrational structure, to understand the effects of the propyl group at the N(3) and of the methyl group at the C(2) position, and to analyze the resulting cation-anion interactions. The data indicate that the iodide ion predominantly interacts with the C(2)sbnd H group via hydrogen bonding. Upon methylation, the C(4/5)sbnd H moiety becomes the main interaction site. However, an interaction takes place only with one of the two hydrogen atoms resulting in a split of the initially degenerate CH stretching modes.

Comparison of diffusivity data derived from electrochemical and NMR investigations of the SeCN¯/(SeCN)2/(SeCN)3¯ system in ionic liquids.

PubMed

Solangi, Amber; Bond, Alan M; Burgar, Iko; Hollenkamp, Anthony F; Horne, Michael D; Rüther, Thomas; Zhao, Chuan

2011-06-02

Electrochemical studies in room temperature ionic liquids are often hampered by their relatively high viscosity. However, in some circumstances, fast exchange between participating electroactive species has provided beneficial enhancement of charge transport. The iodide (I¯)/iodine (I(2))/triiodide (I(3)¯) redox system that introduces exchange via the I¯ + I(2) ⇌ I(3)¯ process is a well documented example because it is used as a redox mediator in dye-sensitized solar cells. To provide enhanced understanding of ion movement in RTIL media, a combined electrochemical and NMR study of diffusion in the {SeCN¯-(SeCN)(2)-(SeCN)(3)¯} system has been undertaken in a selection of commonly used RTILs. In this system, each of the Se, C and N nuclei is NMR active. The electrochemical behavior of the pure ionic liquid, [C(4)mim][SeCN], which is synthesized and characterized here for the first time, also has been investigated. Voltammetric studies, which yield readily interpreted diffusion-limited responses under steady-state conditions by means of a Random Assembly of Microdisks (RAM) microelectrode array, have been used to measure electrochemically based diffusion coefficients, while self-diffusion coefficients were measured by pulsed field gradient NMR methods. The diffusivity data, derived from concentration and field gradients respectively, are in good agreement. The NMR data reveal that exchange processes occur between selenocyanate species, but the voltammetric data show the rates of exchange are too slow to enhance charge transfer. Thus, a comparison of the iodide and selenocyanate systems is somewhat paradoxical in that while the latter give RTILs of low viscosity, sluggish exchange kinetics prevent any significant enhancement of charge transfer through direct electron exchange. In contrast, faster exchange between iodide and its oxidation products leads to substantial electron exchange but this effect does not compensate sufficiently for mass transport limitations imposed by the higher viscosity of iodide RTILs.

Overview of insoluble radioactive cesium particles emitted from the Fukushima Dai-ichi Nuclear Power Station

NASA Astrophysics Data System (ADS)

Satou, Yukihiko

2017-04-01

In the early stage of the Fukushima Dai-ichi Nuclear Power Station (F1NPS) accident, number of spot type contamination has been observed in computed autoradiography (Kashimura 2013, Shibata 2013, Satou 2014). It's means presence of radioactive particles, however, insoluble cesium particle was overlooked because cesium, which is dominant radioactive element in the accident, becomes ionized in the environment. Adachi et al. (2013) showed presence of cesium (Cs)-bearing particles within air dust sample collected at Tsukuba, 170 km south from the Fukushima site, in midnight of 14 to morning of 15 March 2011. These particles were micrometer order small particles and Cs was could be detectable as element using an energy dispersive X-ray spectroscopy (EDX). However, other radioactive elements such as Co-60, Ru-103 and uranium, which were dominant element of radioactive particles delivered from Chernobyl accident, could not detected. Abe et al. (2014) employed a synchrotron radiation (SR)-micro(μ)-X-ray analysis to the Cs-bearing particles, and they were concluded that (1) contained elements derived from nuclear fission processes and from nuclear reactor and fuel materials; (2) were amorphous; (3) were highly oxidized; and (4) consisted of glassy spherules formed from a molten mixture of nuclear fuel and reactor material. In addition, Satou et al. (2016) and Yamaguchi et al. (2016) disclosed that silicate is main component of Cs-bearing particles. Satou et al. (2015) discovered two types of radioactive particles from soil samples collected in the vicinity of the F1NPS. These particles were remained in the natural environment more than four years, silicate is main component in common of each group particles. Group A particles were very similar to Cs-bearing particles reported by Adachi et al. except particle shape. On the other hand, group B is big particles found in north area from the F1NPS, and the strongest particles contained 20 kBq of Cs-137 within a particle. Radioactive ratio of Cs-134/Cs-137 of group A and B is completely different. Group B particles shown 0.92 (mean value) of Cs ratio, and specific radioactivity are much lowers than group A particles. In contrast, activity ratio in group A particles shown 1.0 (mean value), and it was consistent with previous studies by Adachi (2013). The location of soil samples, which was containing group B particles, has been contaminated with radioactive materials from Unit 1 with hydrogen explosion on 12 March (Satou et al. 2014, Chino et al. 2016). More than 300 um of diameter particles has been transported from the Unit 1 of F1NPS. This result shown that the insoluble radioactive cesium particles are emitted from not only Units 2 and/or 3 on 15 March but also Unit 1 on 12 March. The insoluble radioactive Cs particles were spread widely, and it is require to evaluation for particulate percentage of contribution in total emitted radioactive cesium, and long term monitoring of these behaviors.

Content of strontium-90 and cesium-137 in a number of regions of the Baltic Sea in 1982

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lazarev, L.N.; Flegontov, V.M.; Gedenov, L.I.

1985-07-01

The authors present the data gathered from the samples of water and bed deposits taken at various sites in the Baltic Sea, the Gulf of Riga, and the Gulf of Finland. By means of the radiochemical method using ferrocyanide-carbonate concentration, they determine strotium-90 and cesium-137 content. The authors conclude by noting an increase in the cesium-137 content in the deep waters of the Baltic Sea and in bed deposits, and by cautioning that this development commands close attention.

A preliminary deposit model for lithium-cesium-tantalum (LCT) pegmatites

USGS Publications Warehouse

Bradley, Dwight; McCauley, Andrew

2013-01-01

This report is part of an effort by the U.S. Geological Survey to update existing mineral deposit models and to develop new ones. We emphasize practical aspects of pegmatite geology that might directly or indirectly help in exploration for lithium-cesium-tantalum (LCT) pegmatites, or for assessing regions for pegmatite-related mineral resource potential. These deposits are an important link in the world’s supply chain of rare and strategic elements, accounting for about one-third of world lithium production, most of the tantalum, and all of the cesium.

How can we make stable linear monoatomic chains? Gold-cesium binary subnanowires as an example of a charge-transfer-driven approach to alloying.

PubMed

Choi, Young Cheol; Lee, Han Myoung; Kim, Woo Youn; Kwon, S K; Nautiyal, Tashi; Cheng, Da-Yong; Vishwanathan, K; Kim, Kwang S

2007-02-16

On the basis of first-principles calculations of clusters and one dimensional infinitely long subnanowires of the binary systems, we find that alkali-noble metal alloy wires show better linearity and stability than either pure alkali metal or noble metal wires. The enhanced alternating charge buildup on atoms by charge transfer helps the atoms line up straight. The cesium doped gold wires showing significant charge transfer from cesium to gold can be stabilized as linear or circular monoatomic chains.

The Effect of Carbonate, Oxalate and Peroxide on the Cesium Loading of Ionsiv IE-910 and IE-911

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fondeur, F.F.

2000-12-19

The Savannah River Site (SRS) continues to examine three processes for the removal of radiocesium from high-level waste. One option involves the use of crystalline silicotitanate (CST) as a non-elutable ion exchange medium. The process uses CST in its engineered form - IONSIV IE-911 made by UOP, LLC. - in a column to contact the liquid waste. Cesium exchanges with sodium ions residing inside the CST particles. The design disposes of the cesium-loaded CST by vitrification within the Defense Waste Processing Facility.

[Blastomogenic effect following single and chronic exposure to a mixture of cesium-137 and strontium-90].

PubMed

Danetskaia, E V; Lavrent'ev, L N; Zapol'skaia, N A

1976-01-01

The rate of tumor incidence in different rhythms of rat stomach exposure to cesium-137 and strontium-90 was analysed. The correlative values of the administered nucleids activity were selected by analogy with their content in global natural fall-out. In single exposure to the concentrations of 400 and 100 mc/per rat of cesium-137 and strontium-90 mixture accordingly, osteogenic osteosarcomas developed approximatley 4 times as frequently as in chronic administration of the same radionucleids in concentrations of 2 and 8 mc/per rat, correspondingly.

High efficiency thermionic converter studies

NASA Technical Reports Server (NTRS)

Huffman, F. N.; Sommer, A. H.; Balestra, C. L.; Briere, T. R.; Lieb, D.; Oettinger, P. E.; Goodale, D. B.

1977-01-01

Research in thermionic energy conversion technology is reported. The objectives were to produce converters suitable for use in out of core space reactors, radioisotope generators, and solar satellites. The development of emitter electrodes that operate at low cesium pressure, stable low work function collector electrodes, and more efficient means of space charge neutralization were investigated to improve thermionic converter performance. Potential improvements in collector properties were noted with evaporated thin film barium oxide coatings. Experiments with cesium carbonate suggest this substance may provide optimum combinations of cesium and oxygen for thermionic conversion.

Cesium frequency standard for lasers at. Sigma. = 1. 06. mu. m

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wallmeroth, K.; Letterer, R.

1990-07-15

High-resolution spectra of the {ital X}{sup 1}{Sigma}{sup +}{sub {ital g}}--{ital A}{sup 1}{Sigma}{sup +}{sub {ital u}} band of molecular cesium at {lambda}=1.06 {mu}m have been measured. An absolute wave-number reference table for lasers emitting at {Sigma} = 1.06 {mu}m has been established. The cesium resonances are calibrated with respect to the well-known molecular-iodine absorption lines at {Sigma} = 0.53 {mu}m. An accuracy of 10{sup {minus}7} has been achieved.

Development of a Screening Approach to Detect Thyroid Disrupting Chemicals that Inhibit the Human Sodium/Iodide Symporter (NIS)

EPA Science Inventory

Thyroid hormone synthesis requires active iodide uptake mediated by the sodium/iodide symporter (NIS). Monovalent anions, such as the environmental contaminant perchlorate, have been well characterized as competitive inhibitors of NIS, yet limited information exists for more stru...

21 CFR 172.375 - Potassium iodide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 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..., will not result in daily ingestion of the additive so as to provide a total amount of iodine in excess...

21 CFR 172.375 - Potassium iodide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 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..., will not result in daily ingestion of the additive so as to provide a total amount of iodine in excess...

The oxidation of reduced nicotinamide nucleotides by hydrogen peroxide in the presence of lactoperoxidase and thiocyanate, iodide or bromide

PubMed Central

McC. Hogg, D.; Jago, G. R.

1970-01-01

Lactoperoxidase (EC 1.11.1.7) catalysed the oxidation of NADH by hydrogen peroxide in the presence of either thiocyanate, iodide or bromide. In the presence of thiocyanate, net oxidation of thiocyanate occurred simultaneously with the oxidation of NADH, but in the presence of iodide or bromide, only the oxidation of NADH occurred to a significant extent. In the presence of thiocyanate or bromide, NADH was oxidized to NAD+ but in the presence of iodide, an oxidation product with spectral and chemical properties distinct from NAD+ was formed. Thiocyanate, iodide and bromide appeared to function in the oxidation of NADH by themselves being oxidized to products which in turn oxidized NADH, rather than by activating the enzyme. Iodine, which oxidized NADH non-enzymically, appeared to be an intermediate in the oxidation of NADH in the presence of iodide. NADPH was oxidized similarly under the same conditions. An assessment was made of the rates of these oxidation reactions, together with the rates of other lactoperoxidase-catalysed reactions, at physiological concentrations of thiocyanate, iodide and bromide. The results indicated that in milk and saliva the oxidation of thiocyanate to a bacterial inhibitor was likely to predominate over the oxidation of NADH. PMID:4317722

Catalytic determination of molybdenum(VI) by means of an iodide ion-selective electrode and a landolt-type hydrogen peroxide-iodide reaction.

PubMed

Kataoka, M; Nishimura, K; Kambara, T

1983-12-01

A trace amount of molybdenum(VI) can be determined by using its catalytic effect on the oxidation of iodide to iodine by hydrogen peroxide in acidic medium. Addition of ascorbic acid added to the reaction mixture produces the Landolt effect, i.e., the iodine produced by the indicator reaction is reduced immediately by the ascorbic add. Hence the concentration of iodide begins to decrease once all the ascorbic acid has been consumed. The induction period is measured by monitoring the concentration of iodide ion with an iodide ion-selective electrode. The reciprocal of the induction period varies linearly with the concentration of molybdenum(VI). The most suitable pH and concentrations of hydrogen peroxide and potassium iodide are found to be 1.5, 5 and 10mM, respectively. An appropriate amount of ascorbic acid is added to the reaction mixture according to the concentration of molybdenum(VI) in the sample solution. A calibration graph with good proportionality is obtained for the molybdenum(VI) concentration range from 0.1 to 160 muM. Iron(III), vanadium(IV), zirconium(IV), tungsten(VI), copper(II) and chromium(VI) interfere, but iron(III) and copper(II) can be masked with EDTA.

Activation of the Nrf2-Keap 1 Pathway in Short-Term Iodide Excess in Thyroid in Rats

PubMed Central

Liang, Xue

2017-01-01

Wistar rats were randomly divided into groups of varying iodide intake: normal iodide; 10 times high iodide; and 100 times high iodide on Days 7, 14, and 28. Insignificant changes were observed in thyroid hormone levels (p > 0.05). Urinary iodine concentration and iodine content in the thyroid glands increased after high consumption of iodide from NI to 100 HI (p < 0.05). The urinary iodine concentration of the 100 HI group on Days 7, 14, and 28 was 60–80 times that of the NI group. The mitochondrial superoxide production and expressions of Nrf2, Srx, and Prx 3 all significantly increased, while Keap 1 significantly decreased in the 100 HI group when compared to the NI or 10 HI group on Days 7, 14, and 28 (p < 0.05). Immunofluorescence staining results showed that Nrf2 was localized in the cytoplasm in NI group. Although Nrf2 was detected in both cytoplasm and nucleus in 10 HI and 100 HI groups, a stronger positive staining was found in the nucleus. We conclude that the activation of the Nrf2-Keap 1 antioxidative defense mechanism may play a crucial role in protecting thyroid function from short-term iodide excess in rats. PMID:28133506

Flavonoids, Thyroid Iodide Uptake and Thyroid Cancer—A Review

PubMed Central

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

Derivation of strontium-90 and cesium-137 residual radioactive material guidelines for the Laboratory for Energy-Related Health Research, University of California, Davis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nimmagadda, M.; Yu, C.

1993-04-01

Residual radioactive material guidelines for strontium-90 and cesium-137 were derived for the Laboratory for Energy-Related Health Research (LEHR) site in Davis, California. The guideline derivation was based on a dose limit of 100 mrem/yr. The US Department of Energy (DOE) residual radioactive material guideline computer code, RESRAD, was used in this evaluation; this code implements the methodology described in the DOE manual for implementing residual radioactive material guidelines. Three potential site utilization scenarios were considered with the assumption that, for a period of 1,000 years following remedial action, the site will be utilized without radiological restrictions. The defined scenarios varymore » with regard to use of the site, time spent at the site, and sources of food consumed. The results of the evaluation indicate that the basic dose limit of 100 mrem/yr will not be exceeded within 1,000 years for either strontium-90 or cesium-137, provided that the soil concentrations of these radionuclides at the LEHR site do not exceed the following levels: 71,000 pCi/g for strontium-90 and 91 pCi/g for cesium-137 for Scenario A (researcher: the expected scenario); 160,000 pCi/g for strontium-90 and 220 pCi/g for cesium-137 for Scenario B (recreationist: a plausible scenario); and 37 pCi/g for strontium-90 and 32 pCi/g for cesium-137 for Scenario C (resident farmer ingesting food produced in the contaminated area: a plausible scenario). The derived guidelines are single-radionuclide guidelines and are linearly proportional to the dose limit used in the calculations. In setting the actual strontium-90 and cesium-137 guidelines for the LEHR site, DOE will apply the as low as reasonably achievable (ALARA) policy to the decision-making process, along with other factors such as whether a particular scenario is reasonable and appropriate.« less

Environmental application of cesium-137 irradiation technology: Sludges and foods

NASA Astrophysics Data System (ADS)

Sivinski, Jacek S.

Several activities have been undertaken to investigate and implement the use of the military byproduct cesium-137 in ways which benefit mankind. Gamma radiation from cesium-137 has been shown to be effective in reducing pathogens in sewage sludge to levels where reuse of the material in public areas meets current regulatory criteria for protection of public health. Food irradiation at doses of 10 kGy or less have been found by international expert committees to be wholesome and safe for human consumption. Cesium-137 can be used as a means of enhancing particular properties of various food commodities by means of sterilization, insect disinfestation, delayed senescence and ripening, and sprout inhibition. This paper discusses the U.S. Department of Energy Beneficial Uses Program research and engineering history, as well as current activities and future plans, relating to both sewage sludge and food irradiation.

Low level detection of Cs-135 and Cs-137 in environmental samples by ICP-MS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liezers, Martin; Farmer, Orville T.; Thomas, Linda MP

2009-10-01

The measurement of the fission product cesium isotopes 135Cs and 137Cs at low femtogram (fg) 10-15 levels in ground water by Inductively Coupled Plasma-Mass Spectrometry ICP-MS is reported. To eliminate the potential natural barium isobaric interference on the cesium isotopes, in-line chromatographic separation of the cesium from barium was performed followed by high sensitivity ICP-MS analysis. A high efficiency desolvating nebulizer system was employed to maximize ICP-MS sensitivity ~10cps/femtogram. The three sigma detection limit measured for 135Cs was 2fg/ml (0.1uBq/ml) and for 137Cs 0.9fg/ml (0.0027Bq/ml) with analysis time of less than 30 minutes/sample. Cesium detection and 135/137 isotope ratio measurementmore » at very low femtogram levels using this method in a ground water matrix is also demonstrated.« less

Cesium and Strontium Retentions Governed by Aluminosilicate Gel in Alkali-Activated Cements

PubMed Central

Jang, Jeong Gook; Park, Sol Moi; Lee, Haeng Ki

2017-01-01

The present study investigates the retention mechanisms of cesium and strontium for alkali-activated cements. Retention mechanisms such as adsorption and precipitation were examined in light of chemical interactions. Batch adsorption experiments and multi-technical characterizations by using X-ray diffraction, zeta potential measurements, and the N2 gas adsorption/desorption methods were conducted for this purpose. Strontium was found to crystalize in alkali-activated cements, while no cesium-bearing crystalline phases were detected. The adsorption kinetics of alkali-activated cements having relatively high adsorption capacities were compatible with pseudo-second-order kinetic model, thereby suggesting that it is governed by complex multistep adsorption. The results provide new insight, demonstrating that characteristics of aluminosilicate gel with a highly negatively charged surface and high micropore surface area facilitated more effective immobilization of cesium and strontium in comparison with calcium silicate hydrates. PMID:28772803

Cesium injection system for negative ion duoplasmatrons

DOEpatents

Kobayashi, Maasaki; Prelec, Krsto; Sluyters, Theodorus J

1978-01-01

Longitudinally extending, foraminous cartridge means having a cylindrical side wall forming one flat, circular, tip end surface and an opposite end; an open-ended cavity, and uniformly spaced orifices for venting the cavity through the side wall in the annulus of a plasma ring for uniformly ejecting cesium for coating the flat, circular, surface. To this end, the cavity is filled with a cesium containing substance and attached to a heater in a hollow-discharge duoplasmatron. By coating the flat circular surface with a uniform monolayer of cesium and locating it in an electrical potential well at the end of a hollow-discharge, ion duoplasmatron source of an annular hydrogen plasma ring, the negative hydrogen production from the duoplasmatron is increased. The negative hydrogen is produced on the flat surface of the cartridge and extracted by the electrical potential well along a trajectory coaxial with the axis of the plasma ring.

[Radioactive cesium analysis in radiation-tainted beef by gamma-ray spectrometry with germanium semiconductor detector].

PubMed

Minatani, Tomiaki; Nagai, Hiroyuki; Nakamura, Masashi; Otsuka, Kimihito; Sakai, Yoshimichi

2012-01-01

The detection limit and precision of radioactive cesium measurement in beef by gamma-ray spectrometry with a germanium semiconductor detector were evaluated. Measurement for 2,000 seconds using a U-8 container (100 mL) provided a detection limit of radioactive cesium (the sum of 134Cs and 137Cs) of around 20 Bq/kg. The 99% confidence interval of the measurement of provisional maximum residue limit level (491 Bq/kg) samples ranged from 447 to 535 Bq/kg. Beef is heterogeneous, containing muscle and complex fat layers. Depending on the sampled parts, the measurement value is variable. It was found that radioactive cesium content of the muscle layer was clearly different from that of fat, and slight differences were observed among parts of the sample (SD=16.9 Bq/kg), even though the same region (neck block) of beef sample was analyzed.

Study of the overall behavior of thin films of the 7,7,8,8-tetracyanoquinodimethane neutral/anion couple on glassy carbon electrodes in the presence of cesium ion.

PubMed

Gómez, L; Rodríguez-Amaro, R

2008-10-07

The overall electrochemistry of 7,7,8,8-tetracyanoquinodimethane thin films on glassy carbon electrodes in media containing Cs+ ions is explained in light of a layer-by-layer nucleation and growth model, and kinetic data for the processes involved are reported. Using in situ UV-vis spectroelectrochemistry allowed available mechanistic knowledge on such processes to be expanded and the presence of various intermediates in the redox reactions confirmed.

Formation of titanium diboride coatings during the anodic polarization of titanium in a chloride melt with a low boron oxide content

NASA Astrophysics Data System (ADS)

Elshina, L. A.; Malkov, V. B.; Molchanova, N. G.

2015-02-01

The corrosion-electrochemical behavior of titanium in a molten eutectic mixture of cesium and sodium chlorides containing up to 1 wt % boron oxide is studied in the temperature range 810-870 K in an argon atmosphere. The potential, the current, and the rate of titanium corrosion are determined. The optimum conditions of forming a dense continuous titanium diboride coating on titanium with high adhesion to the metallic base are found for the anodic activation of titanium in the molten electrolyte under study.

Halogens in oil and gas production-associated wastewater.

NASA Astrophysics Data System (ADS)

Harkness, J.; Warner, N. R.; Dwyer, G. S.; Mitch, W.; Vengosh, A.

2014-12-01

Elevated chloride and bromide in oil and gas wastewaters that are released to the environment are one of the major environmental risks in areas impacted by shale gas development [Olmstead et al.,2013]. In addition to direct contamination of streams, the potential for formation of highly toxic disinfection by-products (DBPs) in drinking water in utilities located downstream from disposal sites poses a serious risk to human health. Here we report on the occurrence of iodide in oil and gas wastewater. We conducted systematic measurements of chloride, bromide, and iodide in (1) produced waters from conventional oil and gas wells from the Appalachian Basin; (2) hydraulic fracturing flowback fluids from unconventional Marcellus and Fayetteville shale gas, (3) effluents from a shale gas spill site in West Virginia; (4) effluents of oil and gas wastewater disposed to surface water from three brine treatment facilities in western Pennsylvania; and (5) surface waters downstream from the brine treatment facilities. Iodide concentration was measured by isotope dilution-inductively coupled plasma-mass spectrometry, which allowed for a more accurate measurement of iodide in a salt-rich matrix. Iodide in both conventional and unconventional oil and gas produced and flowback waters varied from 1 mg/L to 55 mg/L, with no systematic enrichment in hydraulic fracturing fluids. The similarity in iodide content between the unconventional Marcellus flowback waters and the conventional Appalachian produced waters clearly indicate that the hydraulic fracturing process does not induce additional iodide and the iodide content is related to natural variations in the host formations. Our data show that effluents from the brine treatment facilities have elevated iodide (mean = 20.9±1 mg/L) compared to local surface waters (0.03± 0.1 mg/L). These results indicate that iodide, in addition to chloride and bromide in wastewater from oil and gas production, poses an additional risk to downstream surface water quality and drinking water utilities given the potential of formation of iodate-DBPs in drinking water. Olmstead, S.M. et al. (2013). Shale gas development impacts on surface water quality in Pennsylvania, PNAS, 110, 4962-4967.

SELECTIVE REMOVAL OF STRONTIUM AND CESIUM FROM SIMULATED WASTE SOLUTION WITH TITANATE ION-EXCHANGERS IN A FILTER CARTRIDGE CONFIGURATIONS-12092

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oji, L.; Martin, K.; Hobbs, D.

2012-01-03

Experimental results for the selective removal of strontium and cesium from simulated waste solutions with monosodium titanate and crystalline silicotitanate laden filter cartridges are presented. In these proof-of-principle tests, effective uptake of both strontium-85 and cesium-137 were observed using ion-exchangers in this filter cartridge configuration. At low salt simulant conditions, the instantaneous decontamination factor for strontium-85 with monosodium titanate impregnated filter membrane cartridges measured 26, representing 96% strontium-85 removal efficiency. On the other hand, the strontium-85 instantaneous decontamination factor with co-sintered active monosodium titanate cartridges measured 40 or 98% Sr-85 removal efficiency. Strontium-85 removal with the monosodium titanate impregnated membranemore » cartridges and crystalline silicotitanate impregnated membrane cartridges, placed in series arrangement, produced an instantaneous decontamination factor of 41 compared to an instantaneous decontamination factor of 368 for strontium-85 with co-sintered active monosodium titanate cartridges and co-sintered active crystalline silicotitanate cartridges placed in series. Overall, polyethylene co-sintered active titanates cartridges performed as well as titanate impregnated filter membrane cartridges in the uptake of strontium. At low ionic strength conditions, there was a significant uptake of cesium-137 with co-sintered crystalline silicotitanate cartridges. Tests results with crystalline silicotitanate impregnated membrane cartridges for cesium-137 decontamination are currently being re-evaluated. Based on these preliminary findings we conclude that incorporating monosodium titanate and crystalline silicotitanate sorbents into membranes represent a promising method for the semicontinuous removal of radioisotopes of strontium and cesium from nuclear waste solutions.« less

A Cesium fountain frequency standard: Preliminary results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clairon, A.; Laurent, P.; Santarelli, G.

1994-12-31

Laser cooling of atoms has opened up new possibilities in the field of atomic frequency standards. A Cesium atomic fountain, first proposed by Zacharias in 1953, is now feasible: the atoms, first cooled by six laser beams, are launched upward using laser light, pass once through a microwave cavity, continue their ballistic flight and then fall through the same cavity. The long time between the two microwave interactions leads to a Ramsey resonance much narrower than in conventional Cs clocks using thermal atomic beams. The stability and accuracy of such a cesium fountain am very attractive. The use of diodemore » lasers to cool, launch and detect cesium atoms in a low cesium pressure cell allows the construction of a simple and reliable atomic fountain frequency standard. A fountain frequency standard is now in operation at LPTF. A Ramsey resonance as narrow as 0.8 Hz has been obtained. A few days of continuous operation are routinely obtained. In closed loop operation the fountain frequency standard is continuously monitored against a H maser allowing an evaluation of the accuracy of the device. The present short- term frequency stability is about 5.10{sup -13} {tau}{sup -1/2} limited only by the frequency noise of the microwave source. We intend to present a preliminary evaluation of this new standard with a discussion of the major systematic effects which determine the accuracy. The expected accuracy will be at 10-14 level. In addition, we will present a description of the whole design of the cesium fountain.« less

Quantitative determination of cesium binding to ferric hexacyanoferrate: Prussian blue.

PubMed

Faustino, Patrick J; Yang, Yongsheng; Progar, Joseph J; Brownell, Charles R; Sadrieh, Nakissa; May, Joan C; Leutzinger, Eldon; Place, David A; Duffy, Eric P; Houn, Florence; Loewke, Sally A; Mecozzi, Vincent J; Ellison, Christopher D; Khan, Mansoor A; Hussain, Ajaz S; Lyon, Robbe C

2008-05-12

Ferric hexacyanoferrate (Fe4III[FeII(CN)6]3), also known as insoluble Prussian blue (PB) is the active pharmaceutical ingredient (API) of the drug product, Radiogardase. Radiogardase is the first FDA approved medical countermeasure for the treatment of internal contamination with radioactive cesium (Cs) or thallium in the event of a major radiological incident such as a "dirty bomb". A number of pre-clinical and clinical studies have evaluated the use of PB as an investigational decorporation agent to enhance the excretion of metal cations. There are few sources of published in vitro data that detail the binding capacity of cesium to insoluble PB under various chemical and physical conditions. The study objective was to determine the in vitro binding capacity of PB APIs and drug products by evaluating certain chemical and physical factors such as medium pH, particle size, and storage conditions (temperature). In vitro experimental conditions ranged from pH 1 to 9, to cover the range of pH levels that PB may encounter in the gastrointestinal (GI) tract in humans. Measurements of cesium binding were made between 1 and 24h, to cover gastric and intestinal tract residence time using a validated atomic emission spectroscopy (AES) method. The results indicated that pH, exposure time, storage temperature (affecting moisture content) and particle size play significant roles in the cesium binding to both the PB API and the drug product. The lowest cesium binding was observed at gastric pH of 1 and 2, whereas the highest cesium binding was observed at physiological pH of 7.5. It was observed that dry storage conditions resulted in a loss of moisture from PB, which had a significant negative effect on the PB cesium binding capacity at time intervals consistent with gastric residence. Differences were also observed in the binding capacity of PB with different particle sizes. Significant batch to batch differences were also observed in the binding capacity of some PB API and drug products. Our results suggest that certain physiochemical properties affect the initial binding capacity and the overall binding capacity of PB APIs and drug products during conditions that simulated gastric and GI residence time. These physiochemical properties can be utilized as quality attributes to monitor and predict drug product quality under certain manufacturing and storage conditions and may be utilized to enhance the clinical efficacy of PB.

Catalytic spectrophotometric determination of iodide in pharmaceutical preparations and edible salt.

PubMed

El-Ries, M A; Khaled, Elmorsy; Zidane, F I; Ibrahim, S A; Abd-Elmonem, M S

2012-02-01

The catalytic effect of iodide on the oxidation of four dyes: viz. variamine blue (VB), methylene blue (MB), rhodamine B (RB), and malachite green (MG) with different oxidizing agents was investigated for the kinetic spectrophotometric determination of iodide. The above catalyzed reactions were monitored spectrophotometrically by following the change in dye absorbances at 544, 558, 660, or 617 nm for the VB, RB, MB, or MG catalyzed reactions, respectively. Under optimum conditions, iodide can be determined within the concentration levels 0.064-1.27 µg mL(-1) for VB method, 3.20-9.54 µg mL(-1) for RB method, 5.00-19.00 µg mL(-1) for the MB method, and 6.4-19.0 µg mL(-1) for the MG one, with detection limit reaching 0.004 µg mL(-1) iodide. The reported methods were highly sensitive, selective, and free from most interference. Applying the proposed procedures, trace amounts of iodide in pharmaceutical and edible salt samples were successfully determined without separation or pretreatment steps. Copyright © 2011 John Wiley & Sons, Ltd.

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

PubMed

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.

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

NASA Astrophysics Data System (ADS)

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.

A G-quadruplex based fluorescent oligonucleotide turn-on probe towards iodides detection in real samples.

PubMed

Li, Qian; Li, Shuaihua; Chen, Xiu; Bian, Liujiao

2017-09-01

A basket-type G-quadruplex (GQ) fluorescent oligonucleotide (OND) probe is designed to detect iodides dependent on thymine-Hg(II)-thymine (T-Hg(II)-T) base pairs and the intrinsic fluorescence quenching capacity of GQ. In the presence of Hg(II) ions (Hg 2+ ), the two hexachloro-fluorescein-labeled ONDs form a hairpin structure and the fluorophores are dragged close to the GQ, leading to fluorescence quenching of the probe due to photoinduced electron transfer. Upon addition of iodide anions, Hg 2+ are extracted from T-Hg(II)-T complexes which attributes to the stronger binding with iodide anions, resulting in the fluorescence recovery. Through performing the fluorescence quenching and recovery processes, this probe developed a fluorescence turn-on sensor for iodide anions determination over a linear range of 20-200nmol/L with a limit of detection of 5nmol/L. The practical use of the turn-on technology was demonstrated by its application in determination of iodides in water, food, pharmaceutical products and biological samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Draft Genome Sequence of Roseovarius sp. A-2, an Iodide-Oxidizing Bacterium Isolated from Natural Gas Brine Water, Chiba, Japan.

PubMed

Yuliana, Tri; Nakajima, Nobuyoshi; Yamamura, Shigeki; Tomita, Masaru; Suzuki, Haruo; Amachi, Seigo

2017-01-01

Roseovarius sp. A-2 is a heterotrophic iodide (I - )-oxidizing bacterium isolated from iodide-rich natural gas brine water in Chiba, Japan. This strain oxidizes iodide to molecular iodine (I 2 ) by means of an extracellular multicopper oxidase. Here we report the draft genome sequence of strain A-2. The draft genome contained 46 tRNA genes, 1 copy of a 16S-23S-5S rRNA operon, and 4,514 protein coding DNA sequences, of which 1,207 (27%) were hypothetical proteins. The genome contained a gene encoding IoxA, a multicopper oxidase previously found to catalyze the oxidation of iodide in Iodidimonas sp. Q-1. This draft genome provides detailed insights into the metabolism and potential application of Roseovarius sp. A-2.

Influence of the Dirac-Hartree-Fock starting potential on the parity-nonconserving electric-dipole-transition amplitudes in cesium and thallium

NASA Technical Reports Server (NTRS)

Perger, W. F.; Das, B. P.

1987-01-01

The parity-nonconserving electric-dipole-transition amplitudes for the 6s1/2-7s1/2 transition in cesium and the 6p1/2-7p1/2 transition in thallium have been calculated by the Dirac-Hartree-Fock method. The effects of using different Dirac-Hartree-Fock atomic core potentials are examined and the transition amplitudes for both the length and velocity gauges are given. It is found that the parity-nonconserving transition amplitudes exhibit a greater dependence on the starting potential for thallium than for cesium.

Using Cesium for 3D Thematic Visualisations on the Web

NASA Astrophysics Data System (ADS)

Gede, Mátyás

2018-05-01

Cesium (http://cesiumjs.org) is an open source, WebGL-based JavaScript library for virtual globes and 3D maps. It is an excellent tool for 3D thematic visualisations, but to use its full functionality it has to be feed with its own file format, CZML. Unfortunately, this format is not yet supported by any major GIS software. This paper intro- duces a plugin for QGIS, developed by the author, which facilitates the creation of CZML file for various types of visualisations. The usability of Cesium is also examined in various hardware/software environments.

The biological impacts of ingested radioactive materials on the pale grass blue butterfly

NASA Astrophysics Data System (ADS)

Nohara, Chiyo; Hiyama, Atsuki; Taira, Wataru; Tanahara, Akira; Otaki, Joji M.

2014-05-01

A massive amount of radioactive materials has been released into the environment by the Fukushima Dai-ichi Nuclear Power Plant accident, but its biological impacts have rarely been examined. Here, we have quantitatively evaluated the relationship between the dose of ingested radioactive cesium and mortality and abnormality rates using the pale grass blue butterfly, Zizeeria maha. When larvae from Okinawa, which is likely the least polluted locality in Japan, were fed leaves collected from polluted localities, mortality and abnormality rates increased sharply at low doses in response to the ingested cesium dose. This dose-response relationship was best fitted by power function models, which indicated that the half lethal and abnormal doses were 1.9 and 0.76 Bq per larva, corresponding to 54,000 and 22,000 Bq per kilogram body weight, respectively. Both the retention of radioactive cesium in a pupa relative to the ingested dose throughout the larval stage and the accumulation of radioactive cesium in a pupa relative to the activity concentration in a diet were highest at the lowest level of cesium ingested. We conclude that the risk of ingesting a polluted diet is realistic, at least for this butterfly, and likely for certain other organisms living in the polluted area.

Weather from 250 Miles Up: Visualizing Precipitation Satellite Data (and Other Weather Applications) Using CesiumJS

NASA Technical Reports Server (NTRS)

Lammers, Matt

2017-01-01

Geospatial weather visualization remains predominately a two-dimensional endeavor. Even popular advanced tools like the Nullschool Earth display 2-dimensional fields on a 3-dimensional globe. Yet much of the observational data and model output contains detailed three-dimensional fields. In 2014, NASA and JAXA (Japanese Space Agency) launched the Global Precipitation Measurement (GPM) satellite. Its two instruments, the Dual-frequency Precipitation Radar (DPR) and GPM Microwave Imager (GMI) observe much of the Earth's atmosphere between 65 degrees North Latitude and 65 degrees South Latitude. As part of the analysis and visualization tools developed by the Precipitation Processing System (PPS) Group at NASA Goddard, a series of CesiumJS [Using Cesium Markup Language (CZML), JavaScript (JS) and JavaScript Object Notation (JSON)] -based globe viewers have been developed to improve data acquisition decision making and to enhance scientific investigation of the satellite data. Other demos have also been built to illustrate the capabilities of CesiumJS in presenting atmospheric data, including model forecasts of hurricanes, observed surface radar data, and gridded analyses of global precipitation. This talk will present these websites and the various workflows used to convert binary satellite and model data into a form easily integrated with CesiumJS.

The biological impacts of ingested radioactive materials on the pale grass blue butterfly.

PubMed

Nohara, Chiyo; Hiyama, Atsuki; Taira, Wataru; Tanahara, Akira; Otaki, Joji M

2014-05-15

A massive amount of radioactive materials has been released into the environment by the Fukushima Dai-ichi Nuclear Power Plant accident, but its biological impacts have rarely been examined. Here, we have quantitatively evaluated the relationship between the dose of ingested radioactive cesium and mortality and abnormality rates using the pale grass blue butterfly, Zizeeria maha. When larvae from Okinawa, which is likely the least polluted locality in Japan, were fed leaves collected from polluted localities, mortality and abnormality rates increased sharply at low doses in response to the ingested cesium dose. This dose-response relationship was best fitted by power function models, which indicated that the half lethal and abnormal doses were 1.9 and 0.76 Bq per larva, corresponding to 54,000 and 22,000 Bq per kilogram body weight, respectively. Both the retention of radioactive cesium in a pupa relative to the ingested dose throughout the larval stage and the accumulation of radioactive cesium in a pupa relative to the activity concentration in a diet were highest at the lowest level of cesium ingested. We conclude that the risk of ingesting a polluted diet is realistic, at least for this butterfly, and likely for certain other organisms living in the polluted area.

Iodide transport: implications for health and disease

PubMed Central

2014-01-01

Disorders of the thyroid gland are among the most common conditions diagnosed and managed by pediatric endocrinologists. Thyroid hormone synthesis depends on normal iodide transport and knowledge of its regulation is fundamental to understand the etiology and management of congenital and acquired thyroid conditions such as hypothyroidism and hyperthyroidism. The ability of the thyroid to concentrate iodine is also widely used as a tool for the diagnosis of thyroid diseases and in the management and follow up of the most common type of endocrine cancers: papillary and follicular thyroid cancer. More recently, the regulation of iodide transport has also been the center of attention to improve the management of poorly differentiated thyroid cancer. Iodine deficiency disorders (goiter, impaired mental development) due to insufficient nutritional intake remain a universal public health problem. Thyroid function can also be influenced by medications that contain iodide or interfere with iodide metabolism such as iodinated contrast agents, povidone, lithium and amiodarone. In addition, some environmental pollutants such as perchlorate, thiocyanate and nitrates may affect iodide transport. Furthermore, nuclear accidents increase the risk of developing thyroid cancer and the therapy used to prevent exposure to these isotopes relies on the ability of the thyroid to concentrate iodine. The array of disorders involving iodide transport affect individuals during the whole life span and, if undiagnosed or improperly managed, they can have a profound impact on growth, metabolism, cognitive development and quality of life. PMID:25009573

PLEIADES: a picosecond Compton scattering x-ray source for advanced backlighting and time-resolved material studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gibson, D J; Anderson, S G; Barty, C P

2003-10-20

The PLEIADES (Picosecond Laser-Electron Inter-Action for the Dynamical Evaluation of Structures) facility has produced first light at 70 keV. This milestone offers a new opportunity to develop laser-driven, compact, tunable x-ray sources for critical applications such as diagnostics for the National Ignition Facility and time-resolved material studies. The electron beam was focused to 50 {micro}m rms, at 57 MeV, with 260 C of charge, a relative energy spread of 0.2%, and a normalized emittance of 5 mm mrad horizontally and 13 mm mrad vertically. The scattered 820-nm laser pulse had an energy of 180 mJ and a duration of 54more » fs. Initial x-rays were captured with a cooled charge-coupled device using a Cesium Iodide scintillator; the peak photon energy was approximately 78 keV, with a total x-ray flux of 1.3 x 10{sup 6} photons/shot, and the observed angular distribution found to agree very well with three-dimensional codes. Simple K-edge radiography of a tantalum foil showed good agreement with the theoretical divergence-angle dependence of the x-ray energy. Optimization of the x-ray dose is currently underway, with the goal of reaching 10{sup 8} photons per shot and a peak brightness approaching 10{sup 20} photons/mm{sup 2}/mrad{sup 2}/s/0.1%bandwidth.« less

Transformation of sintered CsPbBr 3 nanocrystals to cubic CsPbI 3 and gradient CsPbBr xI 3–x through halide exchange

DOE PAGES

Hoffman, Jacob B.; Schleper, A. Lennart; Kamat, Prashant V.

2016-06-20

All-inorganic cesium lead halide (CsPbX 3, X = Br –, I –) perovskites could potentially provide comparable photovoltaic performance with enhanced stability compared to organic–inorganic lead halide species. However, small-bandgap cubic CsPbI3 has been difficult to study due to challenges forming CsPbI 3 in the cubic phase. Here, a low-temperature procedure to form cubic CsPbI 3 has been developed through a halide exchange reaction using films of sintered CsPbBr 3 nanocrystals. The reaction was found to be strongly dependent upon temperature, featuring an Arrhenius relationship. Additionally, film thickness played a significant role in determining internal film structure at intermediate reactionmore » times. Thin films (50 nm) showed only a small distribution of CsPbBr xI 3–x species, while thicker films (350 nm) exhibited much broader distributions. Furthermore, internal film structure was ordered, featuring a compositional gradient within film. Transient absorption spectroscopy showed the influence of halide exchange on the excited state of the material. In thicker films, charge carriers were rapidly transferred to iodide-rich regions near the film surface within the first several picoseconds after excitation. Furthermore, this ultrafast vectorial charge-transfer process illustrates the potential of utilizing compositional gradients to direct charge flow in perovskite-based photovoltaics.« less

Comparative investigation of the detective quantum efficiency of direct and indirect conversion detector technologies in dedicated breast CT.

PubMed

Kuttig, Jan D; Steiding, Christian; Kolditz, Daniel; Hupfer, Martin; Karolczak, Marek; Kalender, Willi A

2015-06-01

To investigate the dose saving potential of direct-converting CdTe photon-counting detector technology for dedicated breast CT. We analyzed the modulation transfer function (MTF), the noise power spectrum (NPS) and the detective quantum efficiency (DQE) of two detector technologies, suitable for breast CT (BCT): a flat-panel energy-integrating detector with a 70 μm and a 208 μm thick gadolinium oxysulfide (GOS) and a 150 μm thick cesium iodide (CsI) scintillator and a photon-counting detector with a 1000 μm thick CdTe sensor. The measurements for GOS scintillator thicknesses of 70 μm and 208 μm delivered 10% pre-sampled MTF values of 6.6 mm(-1) and 3.2 mm(-1), and DQE(0) values of 23% and 61%. The 10% pre-sampled MTF value for the 150 μm thick CsI scintillator 6.9 mm(-1), and the DQE(0) value was 49%. The CdTe sensor reached a 10% pre-sampled MTF value of 8.5 mm(-1) and a DQE(0) value of 85%. The photon-counting CdTe detector technology allows for significant dose reduction compared to the energy-integrating scintillation detector technology used in BCT today. Our comparative evaluation indicates that a high potential dose saving may be possible for BCT by using CdTe detectors, without loss of spatial resolution. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Printable organometallic perovskite enables large-area, low-dose X-ray imaging

NASA Astrophysics Data System (ADS)

Kim, Yong Churl; Kim, Kwang Hee; Son, Dae-Yong; Jeong, Dong-Nyuk; Seo, Ja-Young; Choi, Yeong Suk; Han, In Taek; Lee, Sang Yoon; Park, Nam-Gyu

2017-10-01

Medical X-ray imaging procedures require digital flat detectors operating at low doses to reduce radiation health risks. Solution-processed organic-inorganic hybrid perovskites have characteristics that make them good candidates for the photoconductive layer of such sensitive detectors. However, such detectors have not yet been built on thin-film transistor arrays because it has been difficult to prepare thick perovskite films (more than a few hundred micrometres) over large areas (a detector is typically 50 centimetres by 50 centimetres). We report here an all-solution-based (in contrast to conventional vacuum processing) synthetic route to producing printable polycrystalline perovskites with sharply faceted large grains having morphologies and optoelectronic properties comparable to those of single crystals. High sensitivities of up to 11 microcoulombs per air KERMA of milligray per square centimetre (μC mGyair-1 cm-2) are achieved under irradiation with a 100-kilovolt bremsstrahlung source, which are at least one order of magnitude higher than the sensitivities achieved with currently used amorphous selenium or thallium-doped cesium iodide detectors. We demonstrate X-ray imaging in a conventional thin-film transistor substrate by embedding an 830-micrometre-thick perovskite film and an additional two interlayers of polymer/perovskite composites to provide conformal interfaces between perovskite films and electrodes that control dark currents and temporal charge carrier transportation. Such an all-solution-based perovskite detector could enable low-dose X-ray imaging, and could also be used in photoconductive devices for radiation imaging, sensing and energy harvesting.

Printable organometallic perovskite enables large-area, low-dose X-ray imaging.

PubMed

Kim, Yong Churl; Kim, Kwang Hee; Son, Dae-Yong; Jeong, Dong-Nyuk; Seo, Ja-Young; Choi, Yeong Suk; Han, In Taek; Lee, Sang Yoon; Park, Nam-Gyu

2017-10-04

Medical X-ray imaging procedures require digital flat detectors operating at low doses to reduce radiation health risks. Solution-processed organic-inorganic hybrid perovskites have characteristics that make them good candidates for the photoconductive layer of such sensitive detectors. However, such detectors have not yet been built on thin-film transistor arrays because it has been difficult to prepare thick perovskite films (more than a few hundred micrometres) over large areas (a detector is typically 50 centimetres by 50 centimetres). We report here an all-solution-based (in contrast to conventional vacuum processing) synthetic route to producing printable polycrystalline perovskites with sharply faceted large grains having morphologies and optoelectronic properties comparable to those of single crystals. High sensitivities of up to 11 microcoulombs per air KERMA of milligray per square centimetre (μC mGy air -1 cm -2 ) are achieved under irradiation with a 100-kilovolt bremsstrahlung source, which are at least one order of magnitude higher than the sensitivities achieved with currently used amorphous selenium or thallium-doped cesium iodide detectors. We demonstrate X-ray imaging in a conventional thin-film transistor substrate by embedding an 830-micrometre-thick perovskite film and an additional two interlayers of polymer/perovskite composites to provide conformal interfaces between perovskite films and electrodes that control dark currents and temporal charge carrier transportation. Such an all-solution-based perovskite detector could enable low-dose X-ray imaging, and could also be used in photoconductive devices for radiation imaging, sensing and energy harvesting.

Direct synthesis of alkenyl iodides via indium-catalyzed iodoalkylation of alkynes with alcohols and aqueous HI.

PubMed

Wu, Chao; Wang, Zheng; Hu, Zhan; Zeng, Fei; Zhang, Xing-Yu; Cao, Zhong; Tang, Zilong; He, Wei-Min; Xu, Xin-Hua

2018-05-02

A convenient and efficient indium-catalyzed approach to synthesize alkenyl iodides has been developed through direct iodoalkylation of alkynes with alcohols and aqueous HI under mild conditions. This catalytic protocol offers an attractive approach for the synthesis of a diverse range of alkenyl iodides in good to excellent yields.

The pathogenesis of iodide mumps: A case report.

PubMed

Zhang, Guilian; Li, Tao; Wang, Heying; Liu, Jiao

2017-11-01

Iodide mumps is an uncommon condition, induced by iodide-containing contrast, and is characterized by a rapid, painless enlargement of the bilateral or unilateral salivary gland. At present, the pathogenesis of iodide mumps is not yet clear. It may be related to an idiosyncratic reaction, a toxic accumulation of iodine in the gland duct, or renal function damage leading to an iodine excretion disorder. This paper reports the clinical manifestations and magnetic resonance imaging results of one case of iodide mumps, which occurred after digital subtraction angiography. A 66-year-old Chinese man presented to our department with a 1-month speech barrier and 1 day of vomiting. He had the history of high blood sugar, the history of high blood pressure and the history of Vitiligo. He had no history of allergies and had never previously received iodide-containing contrast. His renal function and other laboratory examinations were normal. During the digital subtraction angiography (DSA), the patient received approximately 130 mL of nonionic contrast agent (iodixanol). Five hours postsurgery, the patient experienced bilateral parotid enlargement with no other discomfort, such as pain, fever, skin redness, itching, hives, nausea, vomiting, or respiratory abnormalities. We thought the diagnosis was iodide mumps. Intravenous dexamethasone (5 mg) was administered. 20 hours post-DSA, after which the bilateral parotid shrunk. By 4 days postsurgery, the patient's bilateral parotid had recovered completely. We found no obvious abnormal sequence signal in diffusion magnetic resonance imaging or the corresponding apparent diffusion coefficient. Our findings suggest that vasogenic edema may play an important role in the pathogenesis of iodide mumps. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

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

PubMed

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

2016-07-01

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 dip versus barrier dip, and application method (dip vs. spray) to ensure safe iodine levels in dairy milk when these products are used. The iodine exposure study was performed during a 2-wk period. The trial farm was purged of all iodine-based disinfection products for 21 d during a prestudy "washout period," which resulted in baseline milk iodide range of 145 to 182 ppb. During the experiment, iodine-based teat dips were used as post-milking teat disinfectants and compared to a non-iodine control disinfectant. Milk iodide residue levels for each treatment was evaluated from composited group samples. Introduction of different iodine-based teat disinfectants increased iodide residue content in milk relative to the control by between 8 and 29 μg/L when averaged across the full trial period. However, residues levels for any treatment remained well below the consumable limit of 500 μg/L. The 0.5% iodine disinfectant increased milk iodide levels by 20 μg/L more compared to the 0.25% iodine. Compared to dip-cup application, spray application significantly increased milk iodide residue by 21 μg/L and utilized approximately 23% more teat dip. This carefully controlled study demonstrated an increase in milk iodide concentrations from iodine disinfectants, but increases were small and within acceptable limits. © 2016 Institute of Food Technologists®

REMOVAL OF CESIUM FROM AQUEOUS SOLUTIONS BY ADSORPTION

DOEpatents

Knoll, K.C.

1963-07-16

A process of removing microquantities of cesium from aqueous solutions also containing macroquantities of other ions by adsorption on clinoptilolite is described. The invention resides in the pretreatment of the clinoptilolite by heating at 400 deg C and cooling prior to use. (AEC)

Cesium-diode performances from the 1963-to-1971 Thermionic Conversion Specialist Conferences

NASA Technical Reports Server (NTRS)

Morris, J. F.

1972-01-01

Indexes and summaries of the conference papers containing cesium-diode results are presented. Lists of converter materials, geometries, conditions, outputs, and lifetimes accompany the references. Simple chemical designations for emitters, collectors, and additives direct the reader to appropriate selections.

Potassium iodide capsule treatment of feline sporotrichosis.

PubMed

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.

Study on the Volatility of Cesium in Dry Ashing Pretreatment and Dissolution of Ash by Microwave Digestion System - 13331

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, Kwang-Soon; Lee, Chang Heon; Ahn, Hong-Joo

2013-07-01

Based on the regulation of the activity concentration of Cs-137, Co-58, Co-60, Fe-55, Ni-59, Ni-63, Sr-90, Nb-94, and Tc-99, and the total alpha from the radioactive waste acceptance criteria, the measurement of the activity concentration of these nuclides in low and intermediate levels of radioactive waste such as in paper, cotton, vinyl and plastic samples was investigated. A dry ashing method was applied to obtain a concentration effect of the samples. Owing to the temperature dependence of the volatility for cesium, the temperature of 300 to 650 deg. C was examined. It was found that 450 deg. C is themore » optimum dry ashing temperature. After dry ashing, the produced ash was dissolved with HNO{sub 3}, HCl, and HF by a high-performance microwave digestion system. The ash sample, for the most part, was completely dissolved with 10 mL of HNO{sub 3}, 4 mL of HCl, and 0.25 mL of HF by a high-performance microwave digestion system using a nova high temperature rotor at 250 deg. C for 90 min until reaching 0.2 g. To confirm the reliability of cesium loss after the performance of the dry ashing procedure, a cesium standard solution for AAS and a Cs-137 standard solution for gamma spectrometry were added to a paper towel or a planchet of stainless steel, respectively. Cesium was measured by AAS, ICP-MS, and gamma spectrometry. The volatility of cesium did not occur until 450 deg. C ashing. (authors)« less

Tungstate-based glass-ceramics for the immobilization of radio cesium

NASA Astrophysics Data System (ADS)

Drabarek, Elizabeth; McLeod, Terry I.; Hanna, John V.; Griffith, Christopher S.; Luca, Vittorio

2009-02-01

The preparation of tungstate-containing glass-ceramic composites (GCC) for the potential immobilization of radio cesium has been considered. The GCC materials were prepared by blending two oxide precursor compositions in various proportions. These included a preformed Cs-containing hexagonal tungsten bronze (HTB) phase (Cs 0.3Ti 0.2W 0.8O 3, P6 3/ mcm) and a blend of silica and other oxides. The use of the HTB phase was motivated on the assumption that a HTB-based adsorbent could be used to remove cesium directly from aqueous high level liquid waste feeds. In the absence of the HTB, glass-ceramics were relatively easily prepared from the Cs-containing glass-forming oxide blend. On melting the mixture a relative complex GCC phase assemblage formed. The principal components of this phase assemblage were determined using X-ray powder diffraction, 133Cs MAS-NMR, and cross-sectional SEM and included glass, various zeolites, scheelite (CaWO 4) and a range of other oxide phases and Cs-containing aluminosilicate. Importantly, under no circumstance was cesium partitioned into the glass phase irrespective of whether or not the composition included the preformed Cs-containing HTB compound. For compositions containing the HTB, cesium was partitioned into one of four major phases including zeolite; Cs-silica-tungstate bronze, pollucite (CsAlSi 2O 6), and an aluminosilicate with an Al/Si ratio close to one. The leach resistance of all materials was evaluated and related to the cesium distribution within the GCC phase assemblages. In general, the GCCs prepared from the HTB had superior durability compared with materials not containing tungsten. Indeed the compositions in many cases had leach resistances comparable to the best ceramics or glass materials.

Web-Based Geospatial Visualization of GPM Data with CesiumJS

NASA Technical Reports Server (NTRS)

Lammers, Matt

2018-01-01

Advancements in the capabilities of JavaScript frameworks and web browsing technology have made online visualization of large geospatial datasets such as those coming from precipitation satellites viable. These data benefit from being visualized on and above a three-dimensional surface. The open-source JavaScript framework CesiumJS (http://cesiumjs.org), developed by Analytical Graphics, Inc., leverages the WebGL protocol to do just that. This presentation will describe how CesiumJS has been used in three-dimensional visualization products developed as part of the NASA Precipitation Processing System (PPS) STORM data-order website. Existing methods of interacting with Global Precipitation Measurement (GPM) Mission data primarily focus on two-dimensional static images, whether displaying vertical slices or horizontal surface/height-level maps. These methods limit interactivity with the robust three-dimensional data coming from the GPM core satellite. Integrating the data with CesiumJS in a web-based user interface has allowed us to create the following products. We have linked with the data-order interface an on-the-fly visualization tool for any GPM/partner satellite orbit. A version of this tool also focuses on high-impact weather events. It enables viewing of combined radar and microwave-derived precipitation data on mobile devices and in a way that can be embedded into other websites. We also have used CesiumJS to visualize a method of integrating gridded precipitation data with modeled wind speeds that animates over time. Emphasis in the presentation will be placed on how a variety of technical methods were used to create these tools, and how the flexibility of the CesiumJS framework facilitates creative approaches to interact with the data.

Fire extinguishant materials

NASA Technical Reports Server (NTRS)

Altman, R. L.; Mayer, L. A.; Ling, A. C. (Inventor)

1983-01-01

Fire extinguishant composition comprising a mixture of a finely divided aluminum compound and alkali metal, stannous or plumbous halide is provided. Aluminum compound may be aluminum hydroxide, alumina or boehmite but preferably it is an alkali metal dawsonite. The metal halide may be an alkali metal, e.g. potassium iodide, bromide or chloride or stannous or plumbous iodide, bromide or chloride. Potassium iodide is preferred.

Mercuric iodide light detector and related method

DOEpatents

Iwanczyk, Jan S.; Barton, Jeff B.; Dabrowski, Andrzej J.; Schnepple, Wayne F.

1986-01-01

Apparatus and method for detecting light involve applying a substantially uniform electrical potential difference between first and second spaced surfaces of a body of mercuric iodide, exposing the first surface to light and measuring an electrical current passed through the body in response to the light. The mercuric iodide may be substantially monocrystalline and the potential may be applied between a substantially transparent conductive layer at the first surface and a second conductive layer at the second surface. In a preferred embodiment, the detector is coupled to a scintillator for passage of light to the mercuric iodide in response to ionizing radiation incident on the scintillator.

Mercuric iodide light detector and related method

DOEpatents

Iwanczyk, J.S.; Barton, J.B.; Dabrowski, A.J.; Schnepple, W.F.

1986-09-23

Apparatus and method for detecting light involve applying a substantially uniform electrical potential difference between first and second spaced surfaces of a body of mercuric iodide, exposing the first surface to light and measuring an electrical current passed through the body in response to the light. The mercuric iodide may be substantially monocrystalline and the potential may be applied between a substantially transparent conductive layer at the first surface and a second conductive layer at the second surface. In a preferred embodiment, the detector is coupled to a scintillator for passage of light to the mercuric iodide in response to ionizing radiation incident on the scintillator. 7 figs.

Iodide Protects Heart Tissue from Reperfusion Injury

PubMed Central

Iwata, Akiko; Morrison, Michael L.; Roth, Mark B.

2014-01-01

Iodine is an elemental nutrient that is essential for mammals. Here we provide evidence for an acute therapeutic role for iodine in ischemia reperfusion injury. Infusion of the reduced form, iodide, but not the oxidized form iodate, reduces heart damage by as much as 75% when delivered intravenously following temporary loss of blood flow but prior to reperfusion of the heart in a mouse model of acute myocardial infarction. Normal thyroid function may be required because loss of thyroid activity abrogates the iodide benefit. Given the high degree of protection and the high degree of safety, iodide should be explored further as a therapy for reperfusion injury. PMID:25379708

Process for the thermochemical production of hydrogen

DOEpatents

Norman, John H.; Russell, Jr., John L.; Porter, II, John T.; McCorkle, Kenneth H.; Roemer, Thomas S.; Sharp, Robert

1978-01-01

Hydrogen is thermochemically produced from water in a cycle wherein a first reaction produces hydrogen iodide and H.sub.2 SO.sub.4 by the reaction of iodine, sulfur dioxide and water under conditions which cause two distinct aqueous phases to be formed, i.e., a lighter sulfuric acid-bearing phase and a heavier hydrogen iodide-bearing phase. After separation of the two phases, the heavier phase containing most of the hydrogen iodide is treated, e.g., at a high temperature, to decompose the hydrogen iodide and recover hydrogen and iodine. The H.sub.2 SO.sub.4 is pyrolyzed to recover sulfur dioxide and produce oxygen.

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

NASA Astrophysics Data System (ADS)

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.

Immobilization of Iodate and Iodide using Iron Oxides through Sorption and Co-precipitation at Hanford Site

NASA Astrophysics Data System (ADS)

Wang, G.; Qafoku, N. P.; Truex, M. J.; Strickland, C. E.; Freedman, V. L.

2017-12-01

Isotopes of iodine were generated during plutonium production at the U.S. Department of Energy (DOE) Hanford Site. The long half-life 129I generated during reactor operations has been released into the subsurface, resulting in several large plumes at the Hanford subsurface. We studied the interaction of iodate (IO3-) and iodide (I-) with Fe oxides. A series of batch experiments were conducted to investigate adsorption and co-precipitation of iodine species in the presence of a variety of Fe oxides, such as ferrihydrite, goethite, hematite and magnetite. In the sorption experiments, each Fe oxide was added to an artificial groundwater containing either iodate or iodide, and reacted at room temperature. The sorption batch experiments for each mineral were conducted at varied initial iodate or iodide concentrations under 3 different pH conditions (pH 5, 7, and 9). In the co-precipitation batch experiments, the initial Fe-mineral-forming solutions were prepared in artificial groundwater containing iodate or iodide. Our results indicate that both sorption and co-precipitation are viable mechanisms of the attenuation of the liquid phase iodine. Species Fe oxides could serve as hosts of iodate and iodide that are present at the Hanford subsurface.

INTERACTIONS BETWEEN CESIUM AND DISPERSED KAOLINITE POWDERS AT HIGH TEMPERATURES FOR TREATMENT OF MIXED WASTES

EPA Science Inventory

Kaolinite sorbents were found to manage emissions of vapor phase cesium, when the kaolinite was injected into the combustor, having maximum value between 1400 and 1500 K. The mechanism of this process and its quantification await further research.

HIGH TEMPERATURE SORPTION OF CESIUM AND STRONTIUM ON DISPERSED KAOLINITE POWDERS

EPA Science Inventory

Sorption of cesium and strontium on kaolinite powders was investigated as a means to minimize the emissions of these metals during certain high-temperature processes currently being developed to isolate and dispose of radiological and mixed wastes. In this work, nonradioactive aq...

Experimental investigation on a diode-pumped cesium-vapor laser stably operated at continuous-wave and pulse regime.

PubMed

Chen, Fei; Xu, Dongdong; Gao, Fei; Zheng, Changbin; Zhang, Kuo; He, Yang; Wang, Chunrui; Guo, Jin

2015-05-04

Employing a fiber-coupled diode-laser with a center wavelength of 852.25 nm and a line width of 0.17 nm, experimental investigation on diode-end-pumped cesium (Cs) vapor laser stably operated at continuous-wave (CW) and pulse regime is carried out. A 5 mm long cesium vapor cell filled with 60 kPa helium and 20 kPa ethane is used as laser medium. Using an output coupler with reflectivity of 48.79%, 1.26 W 894.57 nm CW laser is obtained at an incident pump power of 4.76 W, corresponding an optical-optical efficiency of 26.8% and a slope-efficiency of 28.8%, respectively. The threshold temperature is 67.5 °C. Stable pulsed cesium laser with a maximum average output power of 2.6 W is obtained at a repetition rate of 76 Hz, and the pulse repetition rate can be extend to 1 kHz with a pulse width of 18 μs.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samin, Adib; Li, Xiang; Zhang, Jinsuo

For liquid-sodium-cooled fast nuclear reactor systems, it is crucial to understand the behavior of lanthanides and other potential fission products in liquid sodium or other liquid metal solutions such as liquid cesium-sodium. In this study, we focus on lanthanide behavior in liquid sodium. Using ab initio molecular dynamics, we found that the solubility of cerium in liquid sodium at 1000 K was less than 0.78 at. %, and the diffusion coefficient of cerium in liquid sodium was calculated to be 5.57 × 10{sup −9} m{sup 2}/s. Furthermore, it was found that cerium in small amounts may significantly alter the heat capacity of themore » liquid sodium system. Our results are consistent with the experimental results for similar materials under similar conditions.« less

Biosorption of cesium-137 and strontium-90 by mucilaginous seeds of Ocimum basilicum.

PubMed

Chakraborty, Dipjyoti; Maji, Samir; Bandyopadhyay, Abhijit; Basu, Sukalyan

2007-11-01

Mucilaginous seeds of Ocimum basilicum were used in uptake studies with cesium-137 and strontium-90. Results showed that uptake was dependent on the structural integrity of the mucilage fibrils. Water imbibed seeds showed higher adsorption of both 137Cs and 90Sr in comparison to seeds pretreated with NaOH, HCl and Na-periodate solution. The uptake was pH dependent and while some divalent metal ions had no or little detrimental effect, the alkali metal ions Li+, Na+ and K+ decreased the uptake. The maximum adsorption capacity was 160 mg cesium g(-1) and 247 mg strontium g(-1) seed dry weight.

Performance of preproduction model cesium beam frequency standards for spacecraft applications

NASA Technical Reports Server (NTRS)

Levine, M. W.

1978-01-01

A cesium beam frequency standards for spaceflight application on Navigation Development Satellites was designed and fabricated and preliminary testing was completed. The cesium standard evolved from an earlier prototype model launched aboard NTS-2 and the engineering development model to be launched aboard NTS satellites during 1979. A number of design innovations, including a hybrid analog/digital integrator and the replacement of analog filters and phase detectors by clocked digital sampling techniques are discussed. Thermal and thermal-vacuum testing was concluded and test data are presented. Stability data for 10 to 10,000 seconds averaging interval, measured under laboratory conditions, are shown.

Collisional Dynamics of the Cesium D1 and D2 Transitions

DTIC Science & Technology

2010-09-01

37 14. Comparison of Phase Changing Probability and Polarizability ...Phase Changing Probability and Polarizability for D2 Transition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 25...theoretically determined the values for broadening and shift rates for cesium with Argon , Krypton, and Xenon from the interatomic potentials [27]. The rates

Cesium vapor cycle for an advanced LMFBR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fraas, A.P.

1975-01-01

A review indicates that a cesium vapor topping cycle appears attractive for use in the intermediate fluid circuit of an advanced LMFBR designed for a reactor outlet temperature of 1250$sup 0$F or more and would have the following advantages: (1) it would increase the thermal efficiency by about 5 to 10 points (from approximately 40 percent to approximately 45 to 50 percent) thus reducing the amount of waste heat rejected to the environment by 15 to 30 percent. (2) the higher thermal efficiency should reduce the overall capital cost of the reactor plant in dollars per kilowatt. (3) the cesiummore » can be distilled out of the intermediate fluid circuit to leave it bone-dry, thus greatly reducing the time and cost of maintenance work (particularly for the steam generator). (4) the large volume and low pressure of the cesium vapor region in the cesium condenser-steam generator greatly reduces the magnitude of pressure fluctuations that might occur in the event of a leak in a steam generator tube, and the characteristics inherent in a condenser make it easy to design for rapid concentration of any noncondensibles that may form as a consequence of a steam leak into the cesium region so that a steam leak can be detected easily in the very early stages of its development. (auth)« less

Revisiting History: Encountering Iodine Then and Now--A General Chemistry Laboratory to Observe Iodine from Seaweed

ERIC Educational Resources Information Center

Wahab, M. Farooq

2009-01-01

The history of the discovery of iodine is retold using brown-colored seaweed found commonly along the ocean shore. The seaweed is ashed at a low temperature and the iodides are extracted into boiling water. The iodides are oxidized in acidic medium. Solvent extraction of iodine by oxidation of iodides as well as simple aqueous extraction of iodide…

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

ERIC Educational Resources Information Center

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…

The biogeochemical effect of seaweeds upon close-to natural concentrations of dissolved iodate and iodide in seawater Preliminary study with Laminaria digitata and Fucus serratus

NASA Astrophysics Data System (ADS)

Truesdale, Victor W.

2008-06-01

Toward assessing the biogeochemical significance of seaweeds in relation to dissolved iodine in seawater, the effect of whole seaweeds ( Laminaria digitata and Fucus serratus) upon iodide and iodate, at essentially natural concentrations, has been studied. The weeds were carefully removed from the sub-littoral zone of the Menai Straits and exposed to iodide and iodate at their natural temperature (6 °C), but under continuous illumination. Laminaria digitata was found to decrease the concentration of iodate with an exponential rate constant of 0.008-0.24 h -1. This is a newly discovered process which, if substantiated, will require an entirely new mechanism. Generally, apparent iodide concentration increased except in a run with seawater augmented with iodide, where it first decreased. The rate constant for loss of iodide was 0.014-0.16 h -1. Meanwhile, F. serratus was found not to decrease iodate concentrations, as did L. digitata. Indeed, after ˜30 h iodate concentrations increased, suggesting that the weed may take in iodide before oxidising and releasing it. If substantiated, this finding may offer a way into one of the most elusive of processes within the iodine cycle - iodide oxidation. With both seaweeds sustained long-term increases of apparent iodide concentration are most easily explained as a secretion by the weeds of organic matter which is capable of reducing the Ce(IV) reagent used in determination of total iodine. Modelling of the catalytic method used is provided to support this contention. The possibility of developing this to measure the strain that seaweeds endure in this kind of biogeochemical flux experiment is discussed. A Chemical Oxygen Demand type of approach is applied using Ce(IV) as oxidant. The results of the iodine experiments are contrasted with the several investigations of 131I interaction with seaweeds, which have routinely used discs of weed cut from the frond. It is argued that experiments conducted with stable iodine may measure a different variable to that measured in radio-iodine experiments.

Halide removal from aqueous solution by novel silver-polymeric materials.

PubMed

A M S, Polo; I, Velo-Gala; M, Sánchez-Polo; U, von Gunten; J J, López-Peñalver; J, Rivera-Utrilla

2016-12-15

The objective of this study was to analyze the behavior of a new material, silver-doped polymeric cloth (Ag-cloth), in the removal of bromide and iodide from waters. Silver is immobilized on the cloth, guaranteeing selective adsorption of the halide ions as retained silver halides that therefore do not pass into the solution. Results indicate that Ag 0 reacts with H 2 O 2 in the first phases of the process, yielding Ag + and superoxide radical; however, as the process advances, this radical favors Ag + reduction. Increases in the concentration of H 2 O 2 augment the capacity of the Ag-cloth to remove halides from the medium up to a maximum concentration (55μM), above which the removal capacity remains constant (Xm≅1.3-1.8mg halide/g Ag-cloth). Thus, when there is excess H 2 O 2 in the medium, secondary competitive reactions that take place in the process guarantee a constant Ag + concentration, which defines the maximum adsorption capacity of Ag-cloth, reducing its ability to remove halides. Ag-cloth has a higher capacity to remove iodide than bromide, and the presence of organic matter or chloride reduces its capacity to remove iodide or bromide from water. The results obtained shown that the capacity of Ag 0 with H 2 O 2 significantly varies as a function of the medium pH from 1mg Br - /g Ag-cloth at very low pH to 1.6mg/g Ag-cloth at pH9. Copyright © 2016 Elsevier B.V. All rights reserved.

Two-channel dansyl/tryptophan emitters with a cholic acid bridge as reporters for local hydrophobicity within supramolecular systems based on bile salts.

PubMed

Gomez-Mendoza, M; Marin, M Luisa; Miranda, Miguel A

2014-11-14

The aim of the present work is to develop two-channel emitters to probe local hydrophobicity by means of fluorescence quenching within different biomimetic supramolecular environments. To achieve this goal, the dansyl (Dns) and tryptophan (Trp) fluorophores have been covalently attached to cholic acid (CA) in order to ensure simultaneous incorporation of the two emitting units into the same compartment. In principle, the two fluorophores of the synthesized Dns-CA-Trp probes could either exhibit an orthogonal behavior or display excited state interactions. The fluorescence spectra of 3β-Dns-CA-Trp showed a residual Trp emission band at ca. 350 nm and an enhanced Dns maximum in the 500-550 nm region. This reveals a partial intramolecular energy transfer, which is consistent with the Dns and Trp singlet energies. Thus, the two photoactive units are not orthogonal; nevertheless, 3β-Dns-CA-Trp seems appropriate as a two-channel reporter for the supramolecular systems of interest. Fluorescence quenching of 3β-Dns-CA-Trp by iodide (which remains essentially in bulk water) was examined within sodium cholate, sodium taurocholate, sodium deoxycholate and mixed micelles. Interestingly, a decrease in the emission intensity of the two bands was observed with increasing iodide concentrations. The most remarkable effect was observed for mixed micelles, where the quenching rate constants were one order of magnitude lower than in solution. As anticipated, the quenching efficiency by iodide decreased with increasing hydrophobicity of the microenvironment, a trend that can be correlated with the relative accessibility of the probe to the ionic quencher.

Structures, Phase Transitions and Tricritical Behavior of the Hybrid Perovskite Methyl Ammonium Lead Iodide

DOE PAGES

Whitfield, P. S.; Herron, N.; Guise, W. E.; ...

2016-10-21

Here, we examine the crystal structures and structural phase transitions of the deuterated, partially deuterated and hydrogenous organic-inorganic hybrid perovskite methyl ammonium lead iodide (MAPbI 3) using time-of-flight neutron and synchrotron X-ray powder diffraction. Near 330 K the high temperature cubic phases transformed to a body-centered tetragonal phase. The variation of the order parameter Q for this transition scaled with temperature T as Q (T c-T) , where T c is the critical temperature and the exponent was close to , as predicted for a tricritical phase transition. We also observed coexistence of the cubic and tetragonal phases over amore » range of temperature in all cases, demonstrating that the phase transition was in fact first-order, although still very close to tricritical. Upon cooling further, all the tetragonal phases transformed into a low temperature orthorhombic phase around 160 K, again via a first-order phase transition. Finally, based upon these results, we discuss the impact of the structural phase transitions upon photovoltaic performance of MAPbI 3 based solar cells.« less

Phonon Mode Transformation Across the Orthohombic–Tetragonal Phase Transition in a Lead Iodide Perovskite CH 3 NH 3 PbI 3 : A Terahertz Time-Domain Spectroscopy Approach

DOE PAGES

La-o-vorakiat, Chan; Xia, Huanxin; Kadro, Jeannette; ...

2015-12-03

Here, we study the temperature-dependent phonon modes of the organometallic lead iodide perovskite CH 3NH 3PbI 3 thin film across the terahertz (0.5–3 THz) and temperature (20–300 K) ranges. These modes are related to the vibration of the Pb–I bonds. We found that two phonon modes in the tetragonal phase at room temperature split into four modes in the low-temperature orthorhombic phase. By use of the Lorentz model fitting, we also analyze the critical behavior of this phase transition. The carrier mobility values calculated from the low-temperature phonon mode frequencies, via two theoretical approaches, are found to agree reasonably withmore » the experimental value (~2000 cm 2 V –1 s –1) from a previous time-resolved THz spectroscopy work. Thus, we have established a possible link between terahertz phonon modes and the transport properties of perovskite-based solar cells.« less

Re-entrant relaxor ferroelectricity of methylammonium lead iodide

DOE PAGES

Guo, Haiyan; Liu, Peixue; Zheng, Shichao; ...

2016-09-24

In this paper, we have performed a piezoresponse force microscopy (PFM) study on methylammonium lead iodide (MAPbI 3) thin films in normal (non-resonance, non-band-excitation) contact mode. In contrast to the ferroelectric Pb 0.76Ca 0.24TiO 3 (PCT) control sample, a typical ferroelectric response was not observed. However, a nonlinear electric field dependence of the local PFM amplitude was found in MAPbI 3, similar to PCT. An analysis combining results on structure, dielectric dispersion, and weak ferroelectricity demonstrates that MAPbI 3 is actually a re-entrant relaxor ferroelectric which, upon cooling, enters into a relaxor phase below its ferroelectric phase transition at ~327more » K, due to the balance between the long range ferroelectric order and structural methylammonium group orientational disorder. The ferroelectricity at room temperature is compromised due to the re-entrant relaxor behavior, causing the poor polarization retention or weak ferroelectricity. Finally, our findings essentially conciliate the conflicting experimental results on MAPbI 3's ferroelectricity and are beneficial both for basic understanding as well as for device applications.« less

Simultaneous Analyses and Applications of Multiple Fluorobenzoate and Halide Tracers in Hydrologic Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Q; Moran, J E

2004-01-22

An analytical method that employs ion chromatography has been developed to more fully exploit the use of fluorobenzoic acids (FBAs) and halides as hydrologic tracers. In a single run, this reliable, sensitive, and robust method can simultaneously separate and quantify halides (fluoride, chloride, bromide, and iodide) and up to seven FBAs from other common groundwater constituents (e.g., nitrate and sulfate). The usefulness of this ion chromatographic (IC) analytical method is demonstrated in both field and laboratory tracer experiments. Field experiments in unsaturated tuff featuring fractures or a fault show that this efficient and cost-effective method helps achieve the objectives ofmore » tracer studies that use multiple FBAs and/or diffusivity tracers (simultaneous use of one or more FBA and halide). The field study examines the hydrologic response of fractures and the matrix to different flow rates and the contribution of matrix diffusion in chemical transport. Laboratory tracer experiments with eight geologic media from across the United States--mostly from Department of Energy facilities where groundwater contamination is prevalent and where subsurface characterization employing tracers has been ongoing or is in need--reveal several insights about tracer transport behavior: (1) Bromide and FBAs are not always transported conservatively. (2) The delayed transport of these anionic tracers is likely related to geologic media characteristics, such as organic matter, pH, iron oxide content, and clay mineralogy. (3) Any use of iodine as a hydrologic tracer should take into account the different sorption behaviors of iodide and iodate and the possible conversion of iodine's initial chemical form. (4) The transport behavior of potential FBA and halide tracers under relevant geochemical conditions should be evaluated before beginning ambitious, large-scale field tracer experiments.« less

The Effect of Alkaline Earth Metal on the Cesium Loading of Ionsiv(R) IE-910 and IE-911

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fondeur, F.F.

2001-01-16

This study investigated the effect of variances in alkaline earth metal concentrations on cesium loading of IONSIV(R) IE-911. The study focused on Savannah River Site (SRS) ''average'' solution with varying amounts of calcium, barium and magnesium.

CESIUM RECOVERY FROM AQUEOUS SOLUTIONS

DOEpatents

Goodall, C.A.

1960-09-13

A process is given for precipitating cesium on zinc ferricyanide (at least 0.0004 M) from aqueous solutions containing mineral acid in a concentration of from 0.2 N acidity to 0.61 N acid-deficiency and advantageously, but not necessarily, also aluminum nitrate in a concentration of from l to 2.5 M.

Measurement of cesium diffusion coefficients in graphite IG-110

NASA Astrophysics Data System (ADS)

Carter, L. M.; Brockman, J. D.; Loyalka, S. K.; Robertson, J. D.

2015-05-01

An understanding of the transport of fission products in High Temperature Gas-Cooled Reactors (HTGRs) is needed for operational safety as well as source term estimations. We have measured diffusion coefficients of Cs in IG-110 by using the release method, wherein we infused small graphite spheres with Cs and measured the release rates using ICP-MS. Diffusion behavior was investigated in the temperature range of 1100-1300 K. We have obtained: DCs = (1.0 ×10-7m2 /s) exp(-1.1/×105J /mol RT) and, compared our results with those available in the literature.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamliton, T F

Rongelap Atoll experienced close-in or local fallout from the U.S. nuclear test program conducted in the northern Marshall Islands between 1946 and 1958. By all internationally agreed scientific criteria, Rongelap Island is considered safe for permanent resettlement. However, the amount of bomb-related radioactivity in soil and vegetation is, on average, about 5 times greater in the northern islands of the atoll because the centerline of the fallout pattern from the 1954 thermonuclear ''Bravo'' test extended over this part of the atoll. The most important radioactive element remaining on the atoll is radioactive cesium (cesium-137). Cesium-137 emits what is called amore » ''gamma ray'' that can penetrate the body and deliver both an external (outside the body) and internal (from inside the body) gamma dose to inhabitants of Rongelap Atoll. Cesium-137 is taken up from the soil into locally grown foodstuffs such as coconut, Pandanus and breadfruit. Significant quantities of cesium-137 may also be found in coconut crab. The internal dose delivered to people eating these products will be directly proportional to the concentration of cesium-137 in the food and the amount consumed. The external gamma dose will depend on the concentration of cesium-137 in the soil and the amount of time spent in the area. The highest concentration of cesium-137 in surface soils of the northern islands of Rongelap Atoll is about equivalent to that measured on Bikini Island. Under the radiation protection criteria adopted by the Republic of the Marshall Islands Nuclear Claims Tribunal, permanent resettlement of these islands would require intervention because of the higher radiation doses that could potentially be delivered to inhabitants living on a diet derived largely from local foods. A more realistic lifestyle scenario is that the resettled population on Rongelap Island will occasionally visit the northern part of the atoll for food gathering, fishing and other recreational activities. It is estimated that a person spending 8 hours (1 work day) in the interior of the Rongelap Atoll northern islands will receive a maximum additional external dose of around 0.1-0.2 mrem per day. Furthermore, Lawrence Livermore National Laboratory's environmental monitoring continues to show that the marine environment contains very low levels of bomb radioactivity. Similarly, the occasional consumption of terrestrial foods including coconut crab from the northern islands is not expected to add significantly to the radiological health risk of living on Rongelap Island. The average annual effective ingestion dose for Rongelap Island resettlement in 2002 is estimated to be around 1-2 mrem per year when imported foods are made available and proposed remediation efforts take effect. This estimate is about twice that of the Rongelap Island resettlement worker population using direct measurements from the whole body counting program. Resettlement workers presently living on the islands receive an average internal dose from cesium-137 of less than 1 mrem (0.01 mSv) per year. These workers are known to eat locally grown foods and coconut crabs collected from the northern islands. The highest individual dose observed was 4 mrem (0.04 mSv) per year. Under the guidelines adopted by the Republic of the Marshall Islands Nuclear Claims Tribunal, it is concluded that diving, fishing and visiting any northern island of Rongelap Atoll are safe activities for limited periods. Eating local fish and other marine life such as clams would also be considered safe. Consumption of plant foods from the northern islands of Rongelap Atoll depends on successful implementation of specific remediation measures to ensure dietary intakes of cesium-137 remain at or below levels considered safe. The whole body counting program should continue to monitor the actual internal levels of cesium-137 among people eating plants and coconut crabs gathered from the northern islands of Rongelap Atoll islands until such time that the Nuclear Claims Tribunal guidelines are met.« less

Phase Stability and Electronic Structure of Prospective Sb-Based Mixed Sulfide and Iodide 3D Perovskite (CH3NH3)SbSI2.

PubMed

Li, Tianyang; Wang, Xiaoming; Yan, Yanfa; Mitzi, David B

2018-06-29

Lead-free antimony-based mixed sulfide and iodide perovskite phases have recently been reported to be synthesized experimentally and to exhibit reasonable photovoltaic performance. Through a combination of experimental validation and computational analysis, we show no evidence of the formation of the mixed sulfide and iodide perovskite phase, MASbSI 2 (MA = CH 3 NH 3 + ), and instead that the main products are a mixture of the binary and ternary compounds (Sb 2 S 3 and MA 3 Sb 2 I 9 ). Density functional theory calculations also indicate that such a mixed sulfide and iodide perovskite phase should be thermodynamically less stable compared with binary/ternary anion-segregated secondary phases and less likely to be synthesized under equilibrium conditions. Additionally, band structure calculations show that this mixed sulfide and iodide phase, if possible to synthesize (e.g., under nonequilibrium conditions), should have a suitable direct band gap for photovoltaic application.

The Purity of Radioiodide-I131 Assessed by in Vivo and in Vitro Methods

PubMed Central

Fawcett, D. M.; Olde, G. L.; McLeod, L. E.

1962-01-01

Between 41 and 94% of the radioactivity of 24 preparations of I131 supplied without cysteine preservative was non-iodide on chromatographic analysis. Extraneous radio-activity was essentially absent from I131 supplied with cysteine. It was converted to iodide-I131 by 10-3 M cysteine or iodide but not by incubation at pH 2. The average thyroid uptake of I131 containing extraneous radioactivity was significantly lower than the uptake of I131 free from non-iodide impurity in 16 human subjects measured under controlled conditions and in a random group of 669 patients. Incubation of samples of I131 containing non-iodide radioactivity with tyrosine and cupric chloride resulted in the non-enzymatic formation of monoiodotyrosine-I131 either in the presence or absence of thyroid homogenate. Enzymatic formation of monoiodotyrosine-I131 by thyroid homogenates could be demonstrated only when I131 free from extraneous activity was used. ImagesFig. 1Fig. 2 PMID:13891874

Application of direct thermometric analysis in iodometry.

PubMed

Marik-Korda, P; Erdey, L

1970-12-01

Elementary chlorine was determined by a thermometric method using potassium iodide as reagent. The temperature rise corresponding to the heat of reaction was proportional to the chlorine content. Iodine formed in the reaction was also determined with sodium thiosulphate. The heat of the chlorine-iodide reaction is about five times that of the iodine-thiosulphate reaction. Direct determination with potassium iodide is simpler and more rapid than the indirect one.

Passivation Of High-Temperature Superconductors

NASA Technical Reports Server (NTRS)

Vasquez, Richard P.

1991-01-01

Surfaces of high-temperature superconductors passivated with native iodides, sulfides, or sulfates formed by chemical treatments after superconductors grown. Passivating compounds nearly insoluble in and unreactive with water and protect underlying superconductors from effects of moisture. Layers of cuprous iodide and of barium sulfate grown. Other candidate passivating surface films: iodides and sulfides of bismuth, strontium, and thallium. Other proposed techniques for formation of passivating layers include deposition and gas-phase reaction.

Synthesis of Derivatives of Alpha, Omega Difunctional Perfluoroaliphatic Compounds for Low Dielectric Constant Resins

DTIC Science & Technology

1992-03-06

coupling reactions of perfluoroalkyl iodides with certain aryl iodides have been studied. Simple trial tests were carried out between perfluorooctyl iodide...omega Difunctional Perfluoroaliphatic Compounds for Low Dielectric Constant Resins by Robert L. Soulen Department of Chemistry Southwestern University...Difunctional Perfluoroaliphatic Compounds for Low Dielectric Resins 12 PERSONAL AUTHOR(S) Robert L. Soulen 1Ja TYPE OF REPORT 73b TIME COVERED FI DATE OF

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

PubMed Central

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 (ClO2) 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 ClO2 ingestion, it seems that ClO2 does not cause iodide deficiency of sufficient magnitude to account for the decrease in hormonogenesis. Absorption of one or more of iodinated molecules, e.g., nutrients, hormones, or cellular constituents of the alimentary tract having thyromimetic or thyroid inhibitory properties, is a better hypothesis for the effects seen. Images FIGURE 1. a FIGURE 1. b FIGURE 1. c PMID:3816729

Impact of humic acid on the photoreductive degradation of perfluorooctane sulfonate (PFOS) by UV/Iodide process.

PubMed

Sun, Zhuyu; Zhang, Chaojie; Chen, Pei; Zhou, Qi; Hoffmann, Michael R

2017-12-15

Iodide photolysis under UV illumination affords an effective method to produce hydrated electrons (e aq - ) in aqueous solution. Therefore, UV/Iodide photolysis can be utilized for the reductive degradation of many recalcitrant pollutants. However, the effect of naturally occurring organic matter (NOM) such as humic and fulvic acids (HA/FA), which may impact the efficiency of UV/Iodide photoreduction, is poorly understood. In this study, the UV photoreductive degradation of perfluorooctane sulfonate (PFOS) in the presence of I - and HA is studied. PFOS undergoes a relatively slow direct photoreduction in pure water, a moderate level of degradation via UV/Iodide, but a rapid degradation via UV/Iodide/HA photolysis. After 1.5 h of photolysis, 86.0% of the initial [PFOS] was degraded in the presence of both I - and HA with a corresponding defluorination ratio of 55.6%, whereas only 51.7% of PFOS was degraded with a defluorination ratio of 4.4% via UV/Iodide illumination in the absence of HA. The relative enhancement in the presence of HA in the photodegradation of PFOS can be attributed to several factors: a) HA enhances the effective generation of e aq - due to the reduction of I 2 , HOI, IO 3 - and I 3 - back to I - ; b) certain functional groups of HA (i.e., quinones) enhance the electron transfer efficiency as electron shuttles; c) a weakly-bonded association of I - and PFOS with HA increases the reaction probability; and d) absorption of UV photons by HA itself produces e aq - . The degradation and defluorination efficiency of PFOS by UV/Iodide/HA process is dependent on pH and HA concentration. As pH increases from 7.0 to 10.0, the enhancement effect of HA improves significantly. The optimal HA concentration for the degradation of 0.03 mM PFOS is 1.0 mg L -1 . Copyright © 2017 Elsevier Ltd. All rights reserved.

Operational frequency stability of rubidium and cesium frequency standards

NASA Technical Reports Server (NTRS)

Lavery, J. E.

1973-01-01

The frequency stabilities under operational conditions of several commercially available rubidium and cesium frequency standards were determined from experimental data for frequency averaging times from 10 to the 7th power s and are presented in table and graph form. For frequency averaging times between 10 to the 5th power and 10 to the 7th power s, the rubidium standards tested have a stability of between 10 to the minus 12th power and 5 x 10 to the minus 12th power, while the cesium standards have a stability of between 2 x 10 to the minus 13th power and 5 x 10 to the minus 13th power.

Cesium titanium silicate and method of making

DOEpatents

Balmer, Mari L.

1997-01-01

The invention is the new material, a ternary compound of cesium, silica, and titania, together with a method of making the ternary compound, cesium titanium silicate pollucite. More specifically, the invention is Cs.sub.2 Ti.sub.2 Si.sub.4 O.sub.13 pollucite which is a new crystalline phase representing a novel class of Ti-containing zeolites. Compositions contain relatively high Cs.sub.2 O and TiO.sub.2 loadings and are durable glass and ceramic materials. The amount of TiO.sub.2 and Cs.sub.2 that can be incorporated into these glasses and crystalline ceramics far exceeds the limits set for the borosilicate high level waste glass.

Cesium titanium silicate and method of making

DOEpatents

Balmer, M.L.

1997-01-07

The invention is the new material, a ternary compound of cesium, silica, and titania, together with a method of making the ternary compound, cesium titanium silicate pollucite. More specifically, the invention is Cs{sub 2}Ti{sub 2}Si{sub 4}O{sub 13} pollucite which is a new crystalline phase representing a novel class of Ti-containing zeolites. Compositions contain relatively high Cs{sub 2}O and TiO{sub 2} loadings and are durable glass and ceramic materials. The amount of TiO{sub 2} and Cs{sub 2} that can be incorporated into these glasses and crystalline ceramics far exceeds the limits set for the borosilicate high level waste glass. 10 figs.

Cesium 137-Its applications for understanding soil redistribution and deposition patterns on the landscape

USDA-ARS?s Scientific Manuscript database

In the 1960s research began on the application of fallout radionuclides to determine sediment deposition and soil redistribution rates and patterns in agricultural and natural ecosystems. This research was based on the use of fallout 137Cesium (137Cs) from nuclear weapon tests deposited worldwide d...

Laser-cooled cesium fountain clock: design and expected performances

NASA Astrophysics Data System (ADS)

Clairon, Andre; Laurent, Phillipe; Nadir, A.; Santarelli, G.; Drewsen, M.; Grison, D.; Lounis, B.; Salomon, C.

1993-04-01

The use of diode lasers to cool and trap Cesium atoms in a low Cs pressure cell allows the construction of a relatively simple and reliable atomic fountain frequency standard. Here we discuss the design and the potentialities of the Cs clock frequency standards being built at L.P.T.F..

Cesium Eluate Physical Property Determination

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baich, M.A.

2001-02-13

Two bench-scale process simulations of the proposed cesium eluate evaporation process of concentrating eluate produced in the Hanford Site Waste Treatment Plant were conducted. The primary objective of these experiments was to determine the physical properties and the saturation concentration of the eluate evaporator bottoms while producing condensate approximately 0.50 molar HN03.

Method for aqueous radioactive waste treatment

DOEpatents

Bray, L.A.; Burger, L.L.

1994-03-29

Plutonium, strontium, and cesium found in aqueous waste solutions resulting from nuclear fuel processing are removed by contacting the waste solutions with synthetic zeolite incorporating up to about 5 wt % titanium as sodium titanate in an ion exchange system. More than 99.9% of the plutonium, strontium, and cesium are removed from the waste solutions. 3 figures.

Method for aqueous radioactive waste treatment

DOEpatents

Bray, Lane A.; Burger, Leland L.

1994-01-01

Plutonium, strontium, and cesium found in aqueous waste solutions resulting from nuclear fuel processing are removed by contacting the waste solutions with synthetic zeolite incorporating up to about 5 wt % titanium as sodium titanate in an ion exchange system. More than 99.9% of the plutonium, strontium, and cesium are removed from the waste solutions.

Nuclear breeder reactor fuel element with axial tandem stacking and getter

DOEpatents

Gibby, Ronald L.; Lawrence, Leo A.; Woodley, Robert E.; Wilson, Charles N.; Weber, Edward T.; Johnson, Carl E.

1981-01-01

A breeder reactor fuel element having a tandem arrangement of fissile and fertile fuel with a getter for fission product cesium disposed between the fissile and fertile sections. The getter is effective at reactor operating temperatures to isolate the cesium generated by the fissile material from reacting with the fertile fuel section.

An Improvement to Low-Level Radioactive Waste Vitrification Processes.

DTIC Science & Technology

1986-05-01

waste stream. 3 9 Sodium and Potassium tetraphenyl borates are both cited in the literature as having high cesium selectivity. 23󈧝󈧫 The thermal... Ferrate (II) Impregnated Zeolite for Cesium Removal from Radioactive Waste," Nuc. Tech., 58, p.242, ANS, La Grange Park, Illinois, (1982T. 29. F.V

Fission product release from fuel under LWR accident conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Osborne, M.F.; Lorenz, R.A.; Norwood, K.S.

Three tests have provided additional data on fission product release under LWR accident conditions in a temperature range (1400 to 2000/sup 0/C). In the release rate data are compared with curves from a recent NRC-sponsored review of available fission product release data. Although the iodine release in test HI-3 was inexplicably low, the other data points for Kr, I, and Cs fall reasonably close to the corresponding curve, thereby tending to verify the NRC review. The limited data for antimony and silver release fall below the curves. Results of spark source mass spectrometric analyses were in agreement with the gammamore » spectrometric results. Nonradioactive fission products such as Rb and Br appeared to behave like their chemical analogs Cs and I. Results suggest that Te, Ag, Sn, and Sb are released from the fuel in elemental form. Analysis of the cesium and iodine profiles in the thermal gradient tube indicates that iodine was deposited as CsT along with some other less volatile cesium compound. The cesium profiles and chemical reactivity indicate the presence of more than one cesium species.« less

Cesium isotope ratios as indicators of nuclear power plant operations.

PubMed

Delmore, James E; Snyder, Darin C; Tranter, Troy; Mann, Nick R

2011-11-01

There are multiple paths by which radioactive cesium can reach the effluent from reactor operations. The radioactive (135)Cs/(137)Cs ratios are controlled by these paths. In an effort to better understand the origin of this radiation, these (135)Cs/(137)Cs ratios in effluents from three power reactor sites have been measured in offsite samples. These ratios are different from global fallout by up to six fold and as such cannot have a significant component from this source. A cesium ratio for a sample collected outside of the plant boundary provides integration over the operating life of the reactor. A sample collected inside the plant at any given time can be much different from this lifetime ratio. The measured cesium ratios vary significantly for the three reactors and indicate that the multiple paths have widely varying levels of contributions. There are too many ways these isotopes can fractionate to be useful for quantitative evaluations of operating parameters in an offsite sample, although it may be possible to obtain limited qualitative information for an onsite sample. Copyright © 2011 Elsevier Ltd. All rights reserved.

The cesiator - A device for cesium vapor control and impurity purge

NASA Astrophysics Data System (ADS)

Rasor, N. S.; Desplat, J.-L.

A new type of liquid cesium reservoir that maintains a temperature-independent cesium pressure, continuously recirculates cesium vapor through the TFE (thermionic fuel element), and purges it of impurities is discussed. This device, the cesiator, is based on well-established gas-buffered heat pipe principles. The cesiator offers new TFE design options for fission product/impurity handling that eliminate the need for an intercell insulator seal and associated failure modes. Cesiator performance requirements are estimated based on data for expected release of fission products and their effect on TFE performance. The effect of design parameters on cesiator performance is described. Experimentation with an ethanol-metal mock-up revealed an unexpected but desirable mode of operation that autoregulates the pressure drop and flow of vapor in the external circuit and that has been incorporated in the reference design for phase II development. Experimental techniques for measuring the local temperature, pressure, and composition in a condensing vapor were successfully developed. A reference design for a TFE cesiator was defined for prototype design, development, and test.

Standard free energy of formation of iron iodide

NASA Technical Reports Server (NTRS)

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.

Study on gold concentrate leaching by iodine-iodide

NASA Astrophysics Data System (ADS)

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%.

Selective removal of cesium from aqueous solutions with nickel (II) hexacyanoferrate (III) functionalized agricultural residue-walnut shell.

PubMed

Ding, Dahu; Lei, Zhongfang; Yang, Yingnan; Feng, Chuanping; Zhang, Zhenya

2014-04-15

A novel nickel (II) hexacyanoferrate (III) functionalized agricultural residue-walnut shell (Ni(II)HCF(III)-WS) was developed to selectively remove cesium ion (Cs(+)) from aqueous solutions. This paper showed the first integral study on Cs(+) removal behavior and waste reduction analysis by using biomass adsorption material. The results indicated that the removal process was rapid and reached saturation within 2h. As a special characteristic of Ni(II)HCF(III)-WS, acidic condition was preferred for Cs(+) removal, which was useful for extending the application scope of the prepared biomass material in treating acidic radioactive liquid waste. The newly developed Ni(II)HCF(III)-WS could selectively remove Cs(+) though the coexisting ions (Na(+) and K(+) in this study) exhibited negative effects. In addition, approximately 99.8% (in volume) of the liquid waste was reduced by using Ni(II)HCF(III)-WS and furthermore 91.9% (in volume) of the spent biomass material (Cs-Ni(II)HCF(III)-WS) was reduced after incineration (at 500°C for 2h). Due to its relatively high distribution coefficient and significant volume reduction, Ni(II)HCF(III)-WS is expected to be a promising material for Cs(+) removal in practice. Copyright © 2014 Elsevier B.V. All rights reserved.

Carbollide solubility and chemical compatibility summary

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCabe, D.J.

1993-08-17

This report examines the value of the cobalt dicarbollide anion as an effective form of in-tank precipitation. The cobalt dicarbollide anion (CDC) has been investigated for the possible replacement of tetraphenyl borate anion (TPB) for precipitation of cesium in SRS High Level Waste (HLW). The solubility of the cesium CDC in 5 M salt solutions and the reactivity with caustic have been studied extensively. The solubility of CSCDC in a mixture of 4 M sodium nitrate and 1 m sodium hydroxide is {approximately}2 {times} 10{sup {minus}3} M at 40{degrees}C. Furthermore, the CDC decomposes in 1 M sodium hydroxide solution withmore » apparent first order kinetics with a half-life of 7.3 days at 60 {degrees}C and 94 days at 40{degrees}C. Tank temperatures are currently estimated to approach 60{degrees}C during the ITP filtration cycle. This solubility and rapid decomposition of the CDC under highly alkaline conditions and high temperature would require increasing the quantity of CDC and nonradioactive cesium which must be added, increasing the cost of production. Increasing the quantity of CDC would necessitate recovery of the material, probably using a solvent extraction system. Due to the large amount of nonradioactive cesium which must be added, the total amount of precipitate formed exceeds that for TPB precipitation. Also, formation of sodium and/or potassium precipitates compete with cesium salt precipitation in 5 M salt solutions at lower temperature (<30{degrees}C). Decomposition generates hydrogen, which may lead to process complications.« less

eWaterCycle visualisation. combining the strength of NetCDF and Web Map Service: ncWMS

NASA Astrophysics Data System (ADS)

Hut, R.; van Meersbergen, M.; Drost, N.; Van De Giesen, N.

2016-12-01

As a result of the eWatercycle global hydrological forecast we have created Cesium-ncWMS, a web application based on ncWMS and Cesium. ncWMS is a server side application capable of reading any NetCDF file written using the Climate and Forecasting (CF) conventions, and making the data available as a Web Map Service(WMS). ncWMS automatically determines available variables in a file, and creates maps colored according to map data and a user selected color scale. Cesium is a Javascript 3D virtual Globe library. It uses WebGL for rendering, which makes it very fast, and it is capable of displaying a wide variety of data types such as vectors, 3D models, and 2D maps. The forecast results are automatically uploaded to our web server running ncWMS. In turn, the web application can be used to change the settings for color maps and displayed data. The server uses the settings provided by the web application, together with the data in NetCDF to provide WMS image tiles, time series data and legend graphics to the Cesium-NcWMS web application. The user can simultaneously zoom in to the very high resolution forecast results anywhere on the world, and get time series data for any point on the globe. The Cesium-ncWMS visualisation combines a global overview with local relevant information in any browser. See the visualisation live at forecast.ewatercycle.org

Initial results from safety testing of US AGR-2 irradiation test fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morris, Robert Noel; Hunn, John D.; Baldwin, Charles A.

Two cylindrical compacts containing tristructural isotropic (TRISO)-coated particles with kernels that contained a mixture of uranium carbide and uranium oxide (UCO) and two compacts with UO 2-kernel TRISO particles have undergone 1600°C safety testing. These compacts were irradiated in the US Advanced Gas Reactor Fuel Development and Qualification Program's second irradiation test (AGR-2). The time-dependent releases of several radioisotopes ( 110mAg, 134Cs, 137Cs, 154Eu, 155Eu, 90Sr, and 85Kr) were monitored while heating the fuel specimens to 1600°C in flowing helium for 300 h. The UCO compacts behaved similarly to previously reported 1600°C-safety-tested UCO compacts from the AGR-1 irradiation. No failedmore » TRISO or failed SiC were detected (based on krypton and cesium release), and cesium release through intact SiC was very low. Release behavior of silver, europium, and strontium appeared to be dominated by inventory originally released through intact coating layers during irradiation but retained in the compact matrix until it was released during safety testing. Both UO 2 compacts exhibited cesium release from multiple particles whose SiC failed during the safety test. Europium and strontium release from these two UO 2 compacts appeared to be dominated by release from the particles with failed SiC. Silver release was characteristically like the release from the UCO compacts in that an initial release of the majority of silver trapped in the matrix occurred during ramping to 1600°C. However, additional silver release was observed later in the safety testing due to the UO 2 TRISO with failed SiC. Failure of the SiC layer in the UO 2 fuel appears to have been dominated by CO corrosion, as opposed to the palladium degradation observed in AGR-1 UCO fuel.« less

Initial results from safety testing of US AGR-2 irradiation test fuel

DOE PAGES

Morris, Robert Noel; Hunn, John D.; Baldwin, Charles A.; ...

2017-08-18

Two cylindrical compacts containing tristructural isotropic (TRISO)-coated particles with kernels that contained a mixture of uranium carbide and uranium oxide (UCO) and two compacts with UO 2-kernel TRISO particles have undergone 1600°C safety testing. These compacts were irradiated in the US Advanced Gas Reactor Fuel Development and Qualification Program's second irradiation test (AGR-2). The time-dependent releases of several radioisotopes ( 110mAg, 134Cs, 137Cs, 154Eu, 155Eu, 90Sr, and 85Kr) were monitored while heating the fuel specimens to 1600°C in flowing helium for 300 h. The UCO compacts behaved similarly to previously reported 1600°C-safety-tested UCO compacts from the AGR-1 irradiation. No failedmore » TRISO or failed SiC were detected (based on krypton and cesium release), and cesium release through intact SiC was very low. Release behavior of silver, europium, and strontium appeared to be dominated by inventory originally released through intact coating layers during irradiation but retained in the compact matrix until it was released during safety testing. Both UO 2 compacts exhibited cesium release from multiple particles whose SiC failed during the safety test. Europium and strontium release from these two UO 2 compacts appeared to be dominated by release from the particles with failed SiC. Silver release was characteristically like the release from the UCO compacts in that an initial release of the majority of silver trapped in the matrix occurred during ramping to 1600°C. However, additional silver release was observed later in the safety testing due to the UO 2 TRISO with failed SiC. Failure of the SiC layer in the UO 2 fuel appears to have been dominated by CO corrosion, as opposed to the palladium degradation observed in AGR-1 UCO fuel.« less

Measurements of cesium in Arctic beluga and caribou before and after the Fukushima accident of 2011.

PubMed

Stocki, T J; Gamberg, M; Loseto, L; Pellerin, E; Bergman, L; Mercier, J-F; Genovesi, L; Cooke, M; Todd, B; Sandles, D; Whyte, J; Wang, X

2016-10-01

Concern from northern communities following the Fukushima Daiichi nuclear accident of March 2011 has prompted a reassessment of the safety of their traditional foods with respect to radioactivity levels. To this end, a study was conducted to measure the levels of radionuclides in Arctic caribou (Rangifer tarandus) and beluga (Delphinapterus leucas). The main radionuclide of concern is cesium-137, which is easily transferred through the lichen-caribou food chain. Previous studies have been conducted on the cesium-137 levels in Canadian caribou herds from 1958 to 2000, allowing researchers to determine the amount of cesium-137 in caribou specifically attributable to atmospheric weapons testing and the Chernobyl nuclear accident in 1986. In this study, samples of lichens, mushrooms, caribou, beluga and beluga prey collected before and after the Fukushima accident were analyzed for radioactivity levels. Samples were processed and measured using gamma ray spectroscopy to identify the radionuclides present and determine the radioactivity concentration. Both calibration standards and Monte Carlo simulations were used to determine the efficiency of the detectors for the samples, taking into account differences in individual sample sizes as well as matrices. In particular, a careful analysis of the atomic composition of lichens and mushrooms was performed to ensure the efficiencies for these sample types were correct. A comparison of the concentrations from before and after the accident indicated that there was no increase in radioactivity as a result of the atmospheric plume from the Fukushima accident. Some cesium-137, likely attributable to fallout from atmospheric weapons testing of the 1950s and 1960s (since there was no cesium-134 measured in the samples), was measured in the post Fukushima caribou and beluga whale samples; however, this amount was determined to be insignificant for any radiological concern (9.1 ± 1.8 and 0.63 ± 0.23 Bq kg -1  ww respectively). The activity concentrations of cesium-137 was about 200 times smaller than that of natural radioactive potassium in the beluga samples. Both the caribou and beluga results showed that these foods continue to be a healthy food choice for northern Canadians with respect to radioactivity, and this result has been communicated to the nearby northern communities and stakeholders. Copyright © 2016. Published by Elsevier Ltd.

National surveillance for radiological exposures and intentional potassium iodide and iodine product ingestions in the United States associated with the 2011 Japan radiological incident

PubMed Central

LAW, ROYAL K.; SCHIER, JOSH G.; MARTIN, COLLEEN A.; OLIVARES, DAGNY E.; THOMAS, RICHARD G.; BRONSTEIN, ALVIN C.; CHANG, ARTHUR S.

2015-01-01

Background In March of 2011, an earthquake struck Japan causing a tsunami that resulted in a radiological release from the damaged Fukushima Daiichi nuclear power plant. Surveillance for potential radiological and any iodine/iodide product exposures was initiated on the National Poison Data System (NPDS) to target public health messaging needs within the United States (US). Our objectives are to describe self-reported exposures to radiation, potassium iodide (KI) and other iodine/iodide products which occurred during the US federal response and discuss its public health impact. Methods All calls to poison centers associated with the Japan incident were identified from March 11, 2011 to April 18, 2011 in NPDS. Exposure, demographic and health outcome information were collected. Calls about reported radiation exposures and KI or other iodine/iodide product ingestions were then categorized with regard to exposure likelihood based on follow-up information obtained from the PC where each call originated. Reported exposures were subsequently classified as probable exposures (high likelihood of exposure), probable non-exposures (low likelihood of exposure), and suspect exposure (unknown likelihood of exposure). Results We identified 400 calls to PCs associated with the incident, with 340 information requests (no exposure reported) and 60 reported exposures. The majority (n = 194; 57%) of the information requests mentioned one or more substances. Radiation was inquired about most frequently (n = 88; 45%), followed by KI (n = 86; 44%) and other iodine/iodide products (n = 47; 24%). Of the 60 reported exposures, KI was reported most frequently (n = 25; 42%), followed by radiation (n = 22; 37%) and other iodine/iodide products (n = 13; 22%). Among reported KI exposures, most were classified as probable exposures (n = 24; 96%); one was a probable non-exposure. Among reported other iodine/iodide product exposures, most were probable exposures (n = 10, 77%) and the rest were suspect exposures (n = 3; 23%). The reported radiation exposures were classified as suspect exposures (n = 16, 73%) or probable non-exposures (n = 6; 27%). No radiation exposures were classified as probable exposures. A small number of the probable exposures to KI and other iodide/iodine products reported adverse signs or symptoms (n = 9; 26%). The majority of probable exposures had no adverse outcomes (n = 28; 82%). These data identified a potential public health information gap regarding KI and other iodine/iodide products which was then addressed through public health messaging activities. Conclusion During the Japan incident response, surveillance activities using NPDS identified KI and other iodine/iodide products as potential public health concerns within the US, which guided CDC’s public health messaging and communication activities. Regional PCs can provide timely and additional information during a public health emergency to enhance data collected from surveillance activities, which in turn can be used to inform public health decision-making. PMID:23043524

National surveillance for radiological exposures and intentional potassium iodide and iodine product ingestions in the United States associated with the 2011 Japan radiological incident.

PubMed

Law, Royal K; Schier, Josh G; Martin, Colleen A; Olivares, Dagny E; Thomas, Richard G; Bronstein, Alvin C; Chang, Arthur S

2013-01-01

In March of 2011, an earthquake struck Japan causing a tsunami that resulted in a radiological release from the damaged Fukushima Daiichi nuclear power plant. Surveillance for potential radiological and any iodine/iodide product exposures was initiated on the National Poison Data System (NPDS) to target public health messaging needs within the United States (US). Our objectives are to describe self-reported exposures to radiation, potassium iodide (KI) and other iodine/iodide products which occurred during the US federal response and discuss its public health impact. All calls to poison centers associated with the Japan incident were identified from March 11, 2011 to April 18, 2011 in NPDS. Exposure, demographic and health outcome information were collected. Calls about reported radiation exposures and KI or other iodine/iodide product ingestions were then categorized with regard to exposure likelihood based on follow-up information obtained from the PC where each call originated. Reported exposures were subsequently classified as probable exposures (high likelihood of exposure), probable non-exposures (low likelihood of exposure), and suspect exposure (unknown likelihood of exposure). We identified 400 calls to PCs associated with the incident, with 340 information requests (no exposure reported) and 60 reported exposures. The majority (n = 194; 57%) of the information requests mentioned one or more substances. Radiation was inquired about most frequently (n = 88; 45%), followed by KI (n = 86; 44%) and other iodine/iodide products (n = 47; 24%). Of the 60 reported exposures, KI was reported most frequently (n = 25; 42%), followed by radiation (n = 22; 37%) and other iodine/iodide products (n = 13; 22%). Among reported KI exposures, most were classified as probable exposures (n = 24; 96%); one was a probable non-exposure. Among reported other iodine/iodide product exposures, most were probable exposures (n = 10, 77%) and the rest were suspect exposures (n = 3; 23%). The reported radiation exposures were classified as suspect exposures (n = 16, 73%) or probable non-exposures (n = 6; 27%). No radiation exposures were classified as probable exposures. A small number of the probable exposures to KI and other iodide/iodine products reported adverse signs or symptoms (n = 9; 26%). The majority of probable exposures had no adverse outcomes (n = 28; 82%). These data identified a potential public health information gap regarding KI and other iodine/iodide products which was then addressed through public health messaging activities. During the Japan incident response, surveillance activities using NPDS identified KI and other iodine/iodide products as potential public health concerns within the US, which guided CDC's public health messaging and communication activities. Regional PCs can provide timely and additional information during a public health emergency to enhance data collected from surveillance activities, which in turn can be used to inform public health decision-making.

The promotional effects of cesium promoter on higher alcohol synthesis from syngas over cesium-promoted Cu/ZnO/Al2O3 catalysts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Jie; Cai, Qiuxia; Wan, Yan

In this study, the promotional effects of cesium promoter on higher alcohol (C2+OH) synthesis from syngas over Cs-Cu/ZnO/Al2O3 catalysts were investigated using a combined experimental and theoretical density functional theory (DFT) calculation method. In the presence of cesium, the C2+OH productivity increases from 77.1 g•kgcat-1•h-1 to 157.3 g•kgcat-1•h-1 at 583 K due to the enhancement of the initial C–C bond formation. Detailed analysis of chain growth probabilities (CGPs) confirms that initial C–C bond formation is the rate-determining step in the temperature range of 543-583 K. Addition of cesium promoter significantly increases the productivities of 2-methyl-1-propanol, while the CGPs values (C3*more » to 2-methyl-C3*) is almost unaffected. With the assistance of cesium promoter, the CGPs of the initial C–C bond formation step (C1* to C2*) could be increased from 0.13 to 0.25 at 583 K. DFT calculations indicate that the initial C–C bond formation is mainly contributed by the HCO+HCO coupling reaction over the ZnCu(211) model surface. In the presence of the Cs2O, the stabilities of key reaction intermediates such as HCO and H2CO are enhanced which facilitates both HCO+HCO and HCO+H2CO coupling reaction steps with lower activation barriers over the Cs2O-ZnCu(211) surface. The promotional effects of cesium on the C2+OH productivity are also benefited from the competitive CH+HCO coupling reaction over CH hydrogenation that leads to lower alkane formation. In addition, Bader charge analysis suggests that the presence of cesium ions would facilitate the nucleophilic reaction between HCO and H2CO for initial C–C bond formation. This work was supported by the National Natural Science Foundation of China (No. 91545114 and No. 91545203). We appreciate the joint PhD scholarship support from the China Scholarship Council. The authors would also like to thank the support from Collaborative Innovation Center of Chemistry for Energy Materials (2011-iChEM). DM was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences. Computing time was granted by the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL). EMSL is a national scientific user facility located at Pacific Northwest National Laboratory (PNNL) and sponsored by DOE’s Office of Biological and Environmental Research. PNNL is a multiprogram national laboratory operated for DOE by Battelle Memorial Institute. We also appreciate the support from Sinochem Quanzhou Petrochemical Co. Ltd.« less

Iodide Ion Pairing with Highly Charged Ruthenium Polypyridyl Cations in CH3CN.

PubMed

Swords, Wesley B; Li, Guocan; Meyer, Gerald J

2015-05-04

A series of three highly charged cationic ruthenium(II) polypyridyl complexes of the general formula [Ru(deeb)3-x(tmam)x](PF6)2x+2, where deeb is 4,4'-diethyl ester-2,2'-bipyridine and tmam is 4,4'-bis[(trimethylamino)methyl]-2,2'-bipyridine, were synthesized and characterized and are referred to as 1, 2, or 3 based on the number of tmam ligands. Crystals suitable for X-ray crystallography were obtained for the homoleptic complex 3, which was found to possess D3 symmetry over the entire ruthenium complex. The complexes displayed visible absorption spectra typical of metal-to-ligand charge-transfer (MLCT) transitions. In acetonitrile, quasi-reversible waves were assigned to Ru(III/II) electron transfer, with formal reduction potentials that shifted negative as the number of tmam ligands was increased. Room temperature photoluminescence was observed in acetonitrile with quantum yields of ϕ ∼ 0.1 and lifetimes of τ ∼ 2 μs. The spectroscopic and electrochemical data were most consistent with excited-state localization on the deeb ligand for 1 and 2 and on the tmam ligand for 3. The addition of tetrabutylammonium iodide to the complexes dissolved in a CH3CN solution led to changes in the UV-vis absorption spectra consistent with ion pairing. A Benesi-Hildebrand-type analysis of these data revealed equilibrium constants that increased with the cationic charge 1 < 2 < 3 with K = 4000, 4400, and 7000 M(-1). (1)H NMR studies in CD3CN also revealed evidence for iodide ion pairs and indicated that they occur predominantly with iodide localization near the tmam ligand(s). The diastereotopic H atoms on the methylene carbon that link the amine to the bipyridine ring were uniquely sensitive to the presence of iodide; analysis revealed that an iodide "binding pocket" exists wherein iodide forms an adduct with the 3 and 3' bipyridyl H atoms and the quaternized amine. The MLCT excited states were efficiently quenched by iodide. Time-resolved photoluminescence measurements of 1 revealed a static component consistent with rapid electron transfer from iodide in the "binding pocket" to the Ru metal center in the excited state, ket > 10(8) s(-1). The possible relevance of this work to solar energy conversion and dye-sensitized solar cells is discussed.

Status of Plasma Electron Hose Instability Studies in FACET

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adli, Erik; /U. Oslo; England, Robert Joel

In the FACET plasma-wakefield acceleration experiment a dense 23 GeV electron beam will interact with lithium and cesium plasmas, leading to plasma ion-channel formation. The interaction between the electron beam and the plasma sheath-electrons may lead to a fast growing electron hose instability. By using optics dispersion knobs to induce a controlled z-x tilt along the beam entering the plasma, we investigate the transverse behavior of the beam in the plasma as function of the tilt. We seek to quantify limits on the instability in order to further explore potential limitations on future plasma wakefield accelerators due to the electronmore » hose instability. The FACET plasma-wakefield experiment at SLAC will study beam driven plasma wakefield acceleration. A dense 23 GeV electron beam will interact with lithium or cesium plasma, leading to plasma ion-channel formation. The interaction between the electron beam and the plasma sheath-electrons drives the electron hose instability, as first studied by Whittum. While Ref. [2] indicates the possibility of a large instability growth rate for typical beam and plasma parameters, other studies including have shown that several physical effects may mitigate the hosing growth rate substantially. So far there has been no quantitative benchmarking of experimentally observed hosing in previous experiments. At FACET we aim to perform such benchmarking by for example inducing a controlled z-x tilt along the beamentering the plasma, and observing the transverse behavior of the beam in the plasma as function. The long-term objective of these studies is to quantify potential limitations on future plasma wakefield accelerators due to the electron hose instability.« less

Quantum delayed-choice experiment with a single neutral atom.

PubMed

Li, Gang; Zhang, Pengfei; Zhang, Tiancai

2017-10-01

We present a proposal to implement a quantum delayed-choice (QDC) experiment with a single neutral atom, such as a rubidium or cesium atom. In our proposal, a Ramsey interferometer is adopted to observe the wave-like or particle-like behaviors of a single atom depending on the existence or absence of the second π/2-rotation. A quantum-controlled π/2-rotation on target atom is realized through a Rydberg-Rydberg interaction by another ancilla atom. It shows that a heavy neutral atom can also have a morphing behavior between the particle and the wave. The realization of the QDC experiment with such heavy neutral atoms not only is significant to understand the Bohr's complementarity principle in matter-wave and matter-particle domains but also has great potential on the quantum information process with neutral atoms.

Evaluation of anion exchange resins Tulsion A-30 and Indion-930A by application of radioanalytical technique

NASA Astrophysics Data System (ADS)

Singare, P. U.

2014-07-01

Radioanalytical technique using 131I and 82Br was employed to evaluate organic based anion exchange resins Tulsion A-30 and Indion-930A. The evaluation was based on performance of these resins during iodide and bromide ion-isotopic exchange reactions. It was observed that for iodide ion-isotopic exchange reaction by using Tulsion A-30 resin, the values of specific reaction rate (min-1), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log K d were 0.238, 0.477, 0.114, and 11.0, respectively, which was higher than 0.155, 0.360, 0.056, and 7.3, respectively as that obtained by using Indion-930A resins under identical experimental conditions of 40.0°C, 1.000 g of ion exchange resins and 0.003 M labeled iodide ion solution. Also at a constant temperature of 40.0°C, as the concentration of labeled iodide ion solution increases 0.001 to 0.004 M, for Tulsion A-30 resins the percentage of iodide ions exchanged increases from 59.0 to 65.1%, and from 46.4 to 48.8% for Indion-930A resins under identical experimental conditions. The identical trend was observed for both the resins during bromide ion-isotopic exchange reactions. The overall results indicate that under identical experimental conditions, Tulsion A-30 show superior performance over Indion-930A resins. The results of present experimental work have demonstrated that the radioanalytical technique used here can be successfully applied for characterization of different ion exchange resins so as to evaluate their performance under various process parameters.

Propylthiouracil, Perchlorate, and Thyroid-Stimulating Hormone Modulate High Concentrations of Iodide Instigated Mitochondrial Superoxide Production in the Thyroids of Metallothionein I/II Knockout Mice

PubMed Central

Duan, Qi; Wang, Tingting; Zhang, Na; Perera, Vern; Liang, Xue; Abeysekera, Iruni Roshanie

2016-01-01

Background Increased oxidative stress has been suggested as one of the underlying mechanisms in iodide excess-induced thyroid disease. Metallothioneins (MTs) are regarded as scavengers of reactive oxygen species (ROS) in oxidative stress. Our aim is to investigate the effects of propylthiouracil (PTU), a thyroid peroxidase inhibitor, perchlorate (KClO4), a competitive inhibitor of iodide transport, and thyroid stimulating hormone (TSH) on mitochondrial superoxide production instigated by high concentrations of iodide in the thyroids of MT-I/II knockout (MT-I/II KO) mice. Methods Eight-week-old 129S7/SvEvBrd-Mt1tm1Bri Mt2tm1Bri/J (MT-I/II KO) mice and background-matched wild type (WT) mice were used. Results By using a mitochondrial superoxide indicator (MitoSOX Red), lactate dehydrogenase (LDH) release, and methyl thiazolyl tetrazolium (MTT) assay, we demonstrated that the decreased relative viability and increased LDH release and mitochondrial superoxide production induced by potassium iodide (100 µM) can be relieved by 300 µM PTU, 30 µM KClO4, or 10 U/L TSH in the thyroid cell suspensions of both MT-I/II KO and WT mice (P<0.05). Compared to the WT mice, a significant decrease in the relative viability along with a significant increase in LDH release and mitochondrial superoxide production were detected in MT-I/II KO mice(P<0.05). Conclusion We concluded that PTU, KClO4, or TSH relieved the mitochondrial oxidative stress induced by high concentrations of iodide in the thyroids of both MT-I/II KO and WT mice. MT-I/II showed antioxidant effects against high concentrations of iodide-induced mitochondrial superoxide production in the thyroid. PMID:26754589

Identification of Multiple Water-Iodide Species in Concentrated NaI Solutions Based on the Raman Bending Vibration of Water.

PubMed

Besemer, Matthieu; Bloemenkamp, Rob; Ariese, Freek; van Manen, Henk-Jan

2016-02-11

The influence of aqueous electrolytes on the water bending vibration was studied with Raman spectroscopy. For all salts investigated (NaI, NaBr, NaCl, and NaSCN), we observed a nonlinear intensity increase of the water bending vibration with increasing concentration. Different lasers and a tunable frequency-doubled optical parametric oscillator system were used to achieve excitation wavelengths between 785 and 374 nm. Focusing on NaI solutions, the relative enhancement of the water bending vibration was found to increase strongly with excitation photon energy, in line with a preresonance effect from the iodide-water charge-transfer transition. We used multivariate curve resolution (MCR) to decompose the measured Raman spectra of NaI solutions into three interconverting spectral components assigned to bulk water and water molecules interacting with one (X···H-O-H···O) and two (X···H-O-H···X) iodide ions (X = I(-)). The Raman spectrum of solid sodium iodide dihydrate supports the assignment of the latter. Using the MCR results, relative Raman scattering cross sections of 4.0 ± 0.6 and 14.0 ± 0.1 were calculated for the mono- and di-iodide species, respectively (compared to that of bulk water set to unity). In addition, it was found that at relatively low concentrations each iodide ion affects the Raman spectrum of roughly 22 surrounding water molecules, indicating that the influence of iodide extends beyond the first solvation shell. Our results demonstrate that the Raman bending vibration of water is a sensitive probe, providing new insights into anion solvation in aqueous environments.

Laccase Catalyzed Synthesis of Iodinated Phenolic Compounds with Antifungal Activity

PubMed Central

Ihssen, Julian; Schubert, Mark; Thöny-Meyer, Linda; Richter, Michael

2014-01-01

Iodine is a well known antimicrobial compound. Laccase, an oxidoreductase which couples the one electron oxidation of diverse phenolic and non-phenolic substrates to the reduction of oxygen to water, is capable of oxidizing unreactive iodide to reactive iodine. We have shown previously that laccase-iodide treatment of spruce wood results in a wash-out resistant antimicrobial surface. In this study, we investigated whether phenolic compounds such as vanillin, which resembles sub-structures of softwood lignin, can be directly iodinated by reacting with laccase and iodide, resulting in compounds with antifungal activity. HPLC-MS analysis showed that vanillin was converted to iodovanillin by laccase catalysis at an excess of potassium iodide. No conversion of vanillin occurred in the absence of enzyme. The addition of redox mediators in catalytic concentrations increased the rate of iodide oxidation ten-fold and the yield of iodovanillin by 50%. Iodinated phenolic products were also detected when o-vanillin, ethyl vanillin, acetovanillone and methyl vanillate were incubated with laccase and iodide. At an increased educt concentration of 0.1 M an almost one to one molar ratio of iodide to vanillin could be used without compromising conversion rate, and the insoluble iodovanillin product could be recovered by simple centrifugation. The novel enzymatic synthesis procedure fulfills key criteria of green chemistry. Biocatalytically produced iodovanillin and iodo-ethyl vanillin had significant growth inhibitory effects on several wood degrading fungal species. For Trametes versicolor, a species causing white rot of wood, almost complete growth inhibition and a partial biocidal effect was observed on agar plates. Enzymatic tests indicated that the iodinated compounds acted as enzyme responsive, antimicrobial materials. PMID:24594755

Crystal structures of five 1-alkyl-4-aryl-1,2,4-triazol-1-ium halide salts.

PubMed

Guino-O, Marites A; Talbot, Meghan O; Slitts, Michael M; Pham, Theresa N; Audi, Maya C; Janzen, Daron E

2015-06-01

The asymmetric units for the salts 4-(4-fluoro-phen-yl)-1-isopropyl-1,2,4-triazol-1-ium iodide, C11H13FN3 (+)·I(-), (1), 1-isopropyl-4-(4-methyl-phen-yl)-1,2,4-triazol-1-ium iodide, C12H16N3 (+)·I(-), (2), 1-isopropyl-4-phenyl-1,2,4-triazol-1-ium iodide, C11H14N3 (+)·I(-), (3), and 1-methyl-4-phenyl-1,2,4-triazol-1-ium iodide, C9H10N3 (+)·I(-), (4), contain one cation and one iodide ion, whereas in 1-benzyl-4-phenyl-1,2,4-triazol-1-ium bromide monohydrate, C15H14N3 (+)·Br(-)·H2O, (5), there is an additional single water mol-ecule. There is a predominant C-H⋯X(halide) inter-action for all salts, resulting in a two-dimensional extended sheet network between the triazolium cation and the halide ions. For salts with para-substitution on the aryl ring, there is an additional π-anion inter-action between a triazolium carbon and iodide displayed by the layers. For salts without the para-substitution on the aryl ring, the π-π inter-actions are between the triazolium and aryl rings. The melting points of these salts agree with the predicted substituent inductive effects.

A Colorful Experiment

ERIC Educational Resources Information Center

Hunter, C. Bruce

1978-01-01

This experiment, mixing solutions of potassium iodide and lead nitrate to give a bright yellow lead iodide precipitate, often leads students into other topics such as making paint from the precipitate. (BB)

Strategies for the removal of halides from drinking water sources, and their applicability in disinfection by-product minimisation: a critical review.

PubMed

Watson, K; Farré, M J; Knight, N

2012-11-15

The presence of bromide (Br(-)) and iodide (I(-)) in source waters leads to the formation of brominated and iodinated disinfection by-products (DBPs), which are often more toxic than their chlorinated analogues. The increasing scarcity of water resources in Australia is leading to use of impaired and alternative water supplies with high bromide and iodide levels, which may result in the production of more brominated and iodinated DBPs. This review aims to provide a summary of research into bromide and iodide removal from drinking water sources. Bromide and iodide removal techniques have been broadly classified into three categories, namely; membrane, electrochemical and adsorptive techniques. Reverse osmosis, nanofiltration and electrodialysis membrane techniques are reviewed. The electrochemical techniques discussed are electrolysis, capacitive deionization and membrane capacitive deionization. Studies on bromide and iodide removal using adsorptive techniques including; layered double hydroxides, impregnated activated carbons, carbon aerogels, ion exchange resins, aluminium coagulation and soils are also assessed. Halide removal techniques have been compared, and areas for future research have been identified. Copyright © 2012 Elsevier Ltd. All rights reserved.

Iodide accumulation provides kelp with an inorganic antioxidant impacting atmospheric chemistry

PubMed Central

Küpper, Frithjof C.; Carpenter, Lucy J.; McFiggans, Gordon B.; Palmer, Carl J.; Waite, Tim J.; Boneberg, Eva-Maria; Woitsch, Sonja; Weiller, Markus; Abela, Rafael; Grolimund, Daniel; Potin, Philippe; Butler, Alison; Luther, George W.; Kroneck, Peter M. H.; Meyer-Klaucke, Wolfram; Feiters, Martin C.

2008-01-01

Brown algae of the Laminariales (kelps) are the strongest accumulators of iodine among living organisms. They represent a major pump in the global biogeochemical cycle of iodine and, in particular, the major source of iodocarbons in the coastal atmosphere. Nevertheless, the chemical state and biological significance of accumulated iodine have remained unknown to this date. Using x-ray absorption spectroscopy, we show that the accumulated form is iodide, which readily scavenges a variety of reactive oxygen species (ROS). We propose here that its biological role is that of an inorganic antioxidant, the first to be described in a living system. Upon oxidative stress, iodide is effluxed. On the thallus surface and in the apoplast, iodide detoxifies both aqueous oxidants and ozone, the latter resulting in the release of high levels of molecular iodine and the consequent formation of hygroscopic iodine oxides leading to particles, which are precursors to cloud condensation nuclei. In a complementary set of experiments using a heterologous system, iodide was found to effectively scavenge ROS in human blood cells. PMID:18458346

Role of endoplasmic reticulum stress-induced apoptosis in rat thyroid toxicity caused by excess fluoride and/or iodide.

PubMed

Liu, Hongliang; Hou, Changchun; Zeng, Qiang; Zhao, Liang; Cui, Yushan; Yu, Linyu; Wang, Lingzhi; Zhao, Yang; Nie, Junyan; Zhang, Bin; Wang, Aiguo

2016-09-01

Excess fluoride and iodide coexist in drinking water in many regions, but few studies have investigated the single or interactive effects on thyroid in vivo. In our study, Wistar rats were exposed to excess fluoride and/or iodide through drinking water for 2 or 8 months. The structure and function of the thyroid, cells apoptosis and the expression of inositol-requiring enzyme 1 (IRE1) pathway-related factors were analyzed. Results demonstrated that excess fluoride and/or iodide could change thyroid follicular morphology and alter thyroid hormone levels in rats. After 8 months treatment, both single and co-exposure of the two microelements could raise the thyroid cells apoptosis. However, the expressions of IRE1-related factors were only increased in fluoride-alone and the combined groups. In conclusion, thyroid structure and thyroid function were both affected by excess fluoride and/or iodide. IRE1-induced apoptosis were involved in this cytotoxic process caused by fluoride or the combination of two microelements. Copyright © 2016 Elsevier B.V. All rights reserved.

Modulated photophysics of a cationic DNA-staining dye inside protein bovine serum albumin: Study of binding interaction and structural changes of protein

NASA Astrophysics Data System (ADS)

Samanta, Anuva; Jana, Sankar; Ray, Debarati; Guchhait, Nikhil

2014-03-01

The binding affinity of cationic DNA-staining dye, propidium iodide, with transport protein, bovine serum albumin, has been explored using UV-vis absorption, fluorescence, and circular dichroism spectroscopy. Steady state and time resolved fluorescence studies authenticate that fluorescence quenching of bovine serum albumin by propidium iodide is due to bovine serum albumin-propidium iodide complex formation. Thermodynamic parameters obtained from temperature dependent spectral studies cast light on binding interaction between the probe and protein. Site marker competitive binding has been encountered using phenylbutazone and flufenamic acid for site I and site II, respectively. Energy transfer efficiency and distance between bovine serum albumin and propidium iodide have been determined using Förster mechanism. Structural stabilization or destabilization of protein by propidium iodide has been investigated by urea denaturation study. The circular dichroism study as well as FT-IR measurement demonstrates some configurational changes of the protein in presence of the dye. Docking studies support the experimental data thereby reinforcing the binding site of the probe to the subdomain IIA of bovine serum albumin.

Barium iodide and strontium iodide crystals and scintillators implementing the same

DOEpatents

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

2016-11-29

In one embodiment, a material comprises a crystal comprising strontium iodide providing at least 50,000 photons per MeV, where the strontium iodide material is characterized by a volume not less than 1 cm.sup.3. In another embodiment, a scintillator optic includes europium-doped strontium iodide providing at least 50,000 photons per MeV, where the europium in the crystal is primarily Eu.sup.2+, and the europium is present in an amount greater than about 1.6%. A scintillator radiation detector in yet another embodiment includes a scintillator optic comprising SrI.sub.2 and BaI.sub.2, where a ratio of SrI.sub.2 to BaI.sub.2 is in a range of between 0:1 and 1.0, the scintillator optic is a crystal that provides at least 50,000 scintillation photons per MeV and energy resolution of less than about 5% at 662 keV, and the crystal has a volume of 1 cm.sup.3 or more; the scintillator optic contains more than about 2% europium.

Cesium-137 Fallout in Indiana Soil

ERIC Educational Resources Information Center

Whitman, Richard T.

2017-01-01

Atomic weapons testing during the Cold War and accidents at nuclear power plants have resulted in the release of radioactive fallout over great distances. Little is known about levels of fallout deposited in Indiana. The reported study sampled soil in all 92 Indiana counties to determine the present level of cesium-137 from the 2 to 12 centimeter…

Use of charcoals and broiler litter biochar for removal of radioactive cesium (Cs-134 plus Cs-137) from contaminated water

USDA-ARS?s Scientific Manuscript database

Various charcoals (used in food processing and water treatment) and broiler litter biochar were examined for ability to adsorb water-soluble low-level radioactive cesium (ca. 200-250 Bq/kg) extracted from contaminated wheat bran. Among the materials tested, steam activated broiler litter biochar was...

Removal of radioactive cesium (134Cs plus 137Cs) from low-level contaminated water by charcoal and broiler litter biochar

USDA-ARS?s Scientific Manuscript database

Various charcoals (used in food processing and water treatment) and broiler litter biochar were examined for ability to adsorb water-soluble low-level radioactive cesium (ca. 200-250 Bq/kg) extracted from contaminated wheat bran. Among the materials tested, steam activated broiler litter biochar was...

Ultralow-power local laser control of the dimer density in alkali-metal vapors through photodesorption

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jha, Pankaj K.; Scully, Marlan O.; Princeton University, Princeton, New Jersey 08544

2012-08-27

Ultralow-power diode-laser radiation is employed to induce photodesorption of cesium from a partially transparent thin-film cesium adsorbate on a solid surface. Using resonant Raman spectroscopy, we demonstrate that this photodesorption process enables an accurate local optical control of the density of dimer molecules in alkali-metal vapors.