Study of radionuclides speciation with biological molecules of interest by spectrometric techniques

International Nuclear Information System (INIS)

Lourenco, V.

2007-07-01

Mechanisms of complexation and accumulation of the radionuclides at the cellular and molecular level are complex and poorly known because the studies on these subjects are scarce. Within the framework of this thesis, we studied the interactions of europium (analogue of trivalent actinides) and uranium (VI) (actinide) with biological molecules of interest: phyto-chelatins. Their role is to protect cells against intrusions from nonessential heavy metals (thus toxic). These proteins are likely to be implied in the mechanisms of sequestration of radionuclides in living organisms. However, their structure is complex, this is why, in order to better understand their reactivity, we extended our studies to lower entities which constitute them (amino acids and glutathione). We determined solution speciation (stoichiometry, structure) as well as the complexing constants associated with the formation of these species. These studies were undertaken by Time Resolved Laser induced Fluorescence (TRLIF), Electro-Spray Mass Spectrometry (ES-MS), Nuclear Magnetic Resonance (NMR), Fourier Transform Infra-Rouge spectroscopy (FTIR) and Extended X-ray Absorption Fine Structure Spectroscopy (EXAFS). The determination of the complexation constants enabled us to conclude that the complexing capacity of these molecules with respect to radionuclides was moderate (log 10 K 1 < 3, pH 3 or 6), the formed species are mononuclear with only one ligand molecule (1:1). The interaction is performed via oxygenated (hard) groups. The direct complexation of europium with phyto-chelatins at acidic pH was studied jointly by TRLIF and ES-MS. The complexing capacity of these molecules is much higher than that of GSH from which they result. In addition to studies undertaken on synthetic solutions reproducing the 'biological' conditions (pH close to neutrality, ionic strength 0.1 mol/L, etc), tests of cellular contamination were realized. The quantification of integrated europium showed that those are able to

Removal of radionuclides from household water

International Nuclear Information System (INIS)

Vesterbacka, P.; Turtiainen, T.; Haemaelaeinen, K.; Salonen, L.; Arvela, H.

2007-02-01

Research upon methods for removing radionuclides from household water was initiated in Finland in 1995. Three research projects, of which two were carried out with National Technology Agency of Finland and one with CEC, have been completed by the end of 2002. One of the main objectives of the research was to compose a guidebook for consumers and water treatment companies. Radon can be removed from household water by aeration and by activated carbon filtration. Aerators that are well designed and set up can remove over 90% of waterborne radon. The best aerators have achieved removal efficiencies that are nearly 100%. However, setting up an aeration system requires thorough planning. Also, activated carbon filtration removes radon efficiently. The removal efficiencies have been over 90%, often nearly 100%. Depending on the water quality and usage, the carbon batch inside the filter needs to be changed every 2 - 3 years. Since activated carbon filters emit gamma radiation while in use, they should not be installed inside the dwelling but in a separate building or by the well. It is recommended that uranium be removed from drinking water by anion exchange, which is the most efficient removal method for this purpose. Typically, the removal efficiencies are nearly 100%. The one exception is the so called tap filter, the removal efficiency of which depends on uranium concentration in raw water and the rate of water flow. High saline concentration in water may extricate uranium from ion exchange resin. Changes in plumbing pressure or pH-value do not have any significant influence in uranium retention. Removal efficiencies of lead and polonium vary a lot depending on the chemical form in which they occur in water. They can be reliably removed from water by reverse osmosis only. Other treatment methods, such as ion exchange and activated carbon filtration, remove lead and polonium partly. Lead and polonium are removed more efficiently when they are bound onto smaller

Removal of radionuclides from process streams - a review

International Nuclear Information System (INIS)

Itzkovitch, I.J.; Ritcey, G.M.

1979-04-01

This report details the origin and control of radium 226, thorium 230 and lead 210 contamination of mill effluent streams from conventional and non-conventional milling of uranium ores, reviews the basic chemistry of the radionuclides as it relates to potential alternatives for control and presents these alternatives along with a summary of published cost data. The conclusions from the study indicate that the current technology, using sulphuric acid processing, solubilizes only a comparatively small quantity of the radionuclides, with the solid containing approximately the same concentration as the original ore. Present technolgy does not provide for complete removal and isolation of the radionuclides. Current practice for control of thorium 230 in liquid effluents by neutralization is adequate to meet present Governmental guidelines. Radium in solution is presently being controlled by precipitation with barium chloride but levels of less than 3 pCi/L of soluble radium could be difficult if not impossible to achieve consistently by this treatment. Indications are that the concentration of lead 210 in liquid effluent may exceed present guidelines. No specific control procedures are employed for lead 210. Methods of isolating radium 226 are required for treating effluents from conventional milling as well as from alternative processes under development. Ion exchange is suggested as a means of isolating these radionuclides. (OT)

Removal of radionuclides from household water

International Nuclear Information System (INIS)

Vesterbacka, P.; Turtiainen, T.; Haemaelaeinen, K.; Salonen, L.; Arvela, H.

2003-10-01

Research upon methods for removing radionuclides from household water was initiated in Finland in 1995. Three research projects, of which two were carried out with National Technology Agency of Finland and one with CEC, have been completed by the end of 2002. One of the main objectives of the research was to compose a guidebook for consumers and water treatment companies. Radon can be removed from household water by aeration and by activated carbon filtration. Aerators that are well designed and set up can remove over 90% of waterborne radon. The best aerators have achieved removal efficiencies that are nearly 100%. However, setting up an aeration system requires thorough planning. Also, activated carbon filtration removes radon efficiently. The removal efficiencies have been over 90%, often nearly 100%. Depending on the water quality and usage, the carbon batch inside the filter needs to be changed every 2-3 years. Since activated carbon filters emit gamma radiation while in use, they should not be installed inside the dwelling but in a separate building or by the well. It is recommended that uranium be removed from drinking water by anion exchange, which is the most efficient removal method for this purpose. Typically, the removal efficiencies are nearly 100%. The one exception is the so called tap filter, the removal efficiency of which depends on uranium concentration in raw water and the rate of water flow. High saline concentration in water may extricate uranium from ion exchange resin. Changes in plumbing pressure or pH-value do not have any significant influence in uranium retention. Removal efficiencies of lead and polonium vary a lot depending on the chemical form in which they occur in water. They can be reliably removed from water by reverse osmosis only. Other treatment methods, such as ion exchange and activated carbon filtration, remove lead and polonium partly. Lead and polonium are removed more efficiently when they are bound onto smaller particles

Characteristics of transfer of europium ions from phosphoric acid solution into the CaSO4·O.5H2O solid phase

International Nuclear Information System (INIS)

Berdonosova, D.G.; Burlakova, E.V.; Yasenkova, M.A.; Ivanov, L.N.; Melikhov, I.V.

1989-01-01

The mechanism of formation of the precipitated CaSO 4 ·0.5H 2 O phase was studied in detail; the precipitation was performed at 80 degree, equimolar solutions of Ca(H 2 PO 4 ) 2 and H 2 SO 4 in phosphoric acid of 38% concentration being used. The availability of detailed information on the mechanism of formation of CaSO 4 ·0.5H 2 O precipitates determined the choice of conditions of study of capture of rare earths. In particular, H 3 PO 4 of 38% P 2 O 5 concentration was used as the medium of formation of the calcium sulfate precipitate. Europium was chosen as the rare earth. Its behavior in the liquid and solid phases was studied by radiometric and luminescence methods. The radionuclide 152 Eu is convenient as a radioactive tracer while luminescence of europium is structure-sensitive; therefore, europium is often used in physicochemical investigations as a luminescent probe. It follows from the data that most of the europium captured by the precipitate during coagulation of the ultramicrocrystals is retained firmly by the solid phase. Therefore, in order to diminish capture of europium (and other rare earths) by the precipitate coagulation of the latter should be prevented

Sorption of europium by Haro river sand in aqueous solution

International Nuclear Information System (INIS)

Syed Moosa Hasany; Syed Javaid Khurshid

1997-01-01

The sorption of Eu(III) on Haro river sand has been investigated. Influences include composition of the sorptive medium, the concentration of sorbent and sorbate, and shaking time. Haro river sand can be exploited for the preconcentration and removal of europium from very dilute solutions, for the decontamination and treatment of radioactive waste water and effluents from nuclear installations. (Author)

Position Paper on Practicable Performance Criteria for the Removal Efficiency of Volatile Radionuclides

Energy Technology Data Exchange (ETDEWEB)

R. T. Jubin; N. Soelberg; D. M. Strachan

2012-03-01

As a result of fuel reprocessing, volatile radionuclides may be released from the facility stack if no processes are put in place to remove them. The radionuclides that are of concern in this document are 3H, 14C, 85Kr, and 129I. The question we attempted to answer is how efficient must this removal process be for each of these radionuclides? To answer this question, we examined the three regulations that may impact the degree to which these radionuclides must be reduced before process gases can be released from the facility. These regulations are 40 CFR 61 (EPA 2010a), 40 CFR 190(EPA 2010b), and 10 CFR 20 (NRC 2012). These regulations apply to the total radionuclide release and to a particular organ - the thyroid. Because these doses can be divided amongst all the radionuclides in different ways and even within the four radionuclides in question, we provided several cases. We first looked at the inventories for these radionuclides for three fuel types (PWR UOX, PWR MOX, and AHTGR), several burn-up values, and time out of reactor extending to 200 y. We calculated doses to the maximum exposed individual (MEI) with the EPA code CAP-88 (Rosnick 1992). Finally, we looked at two dose cases. Allocating all of the allowable dose to be used by the volatile radionuclides is one case, but, perhaps, unrealistic. In lieu of this, we arbitrarily selected a value of 10% of the allowable dose to be assigned to the volatile radionuclides. We calculated the required decontamination factors (DFs) for both of these cases, including the case for the thyroid dose for which 14C and 129I were the main contributors. With respect to 129I doses, we found that the highest dose was calculated with iodine as a fine particulate. The dose scaled as the fraction of the total 129I that was particulate. Therefore, we assumed for all of our calculations that 100% of the 129I was particulate and allow the user of the results given here to scale our calculated doses to their needs.

Treatment techniques for removing natural radionuclides from drinking water. Final report of the TENAWA project

International Nuclear Information System (INIS)

Annanmaeki, M.; Turtiainen, T.

2000-01-01

TENAWA project (Treatment Techniques for Removing Natural Radionuclides from Drinking Water) was carried out on a cost-shared basic with the European Commission (CEC) under the supervision of Directorate-General XII, Radiation Protection Unit. TENAWA project was started because in several European countries ground water supplies may contain high amounts of natural radionuclides. During the project both laboratory and field research was performed in order to test the applicability of different equipment and techniques for removing natural radionuclides from drinking water. The measurable objectives of the project were: to give recommendations on the most suitable methods for removing radon ( 222 Rn), uranium ( 238,234 U), radium ( 226 , 228 Ra), lead ( 210 Pb) and polonium ( 210 Po) from drinking water of different qualities (i.e. soft, hard, iron-, manganese- and humus-rich, acidic) to test commercially available equipment for its ability to remove radionuclides; to find new materials, absorbents and membranes effective in the removal of radionuclides and to issue guidelines for the treatment and disposal of radioactive wastes produced in water treatment. Radon could be removed efficiently (>95%) from domestic water supplies by both aeration and granular activated carbon (GAC) filtration. Defects in technical reliability or radon removal efficiency were observed in some aerators. The significant drawback of GAC filtration was the elevated gamma dose rates (up to 120 μSv/h) near the filter and the radioactivity of spent GAC. Aeration was found to be a suitable method for removing radon at waterworks, too. The removal efficiencies at waterworks where the aeration process was designed to remove radon or carbon dioxide were 67-99%. If the aeration process was properly designed, removal efficiencies higher than 95% could be attained. Uranium could best be removed (>95%) with strong basic anion exchange resins and radium by applying strong acidic cation exchange resins

Treatment techniques for removing natural radionuclides from drinking water. Final report of the TENAWA project

Energy Technology Data Exchange (ETDEWEB)

Annanmaeki, M.; Turtiainen, T. [eds.

2000-01-01

TENAWA project (Treatment Techniques for Removing Natural Radionuclides from Drinking Water) was carried out on a cost-shared basic with the European Commission (CEC) under the supervision of Directorate-General XII, Radiation Protection Unit. TENAWA project was started because in several European countries ground water supplies may contain high amounts of natural radionuclides. During the project both laboratory and field research was performed in order to test the applicability of different equipment and techniques for removing natural radionuclides from drinking water. The measurable objectives of the project were: to give recommendations on the most suitable methods for removing radon ({sup 222}Rn), uranium ({sup 238,234}U), radium ({sup 226}, {sup 228}Ra), lead ({sup 210}Pb) and polonium ({sup 210}Po) from drinking water of different qualities (i.e. soft, hard, iron-, manganese- and humus-rich, acidic) to test commercially available equipment for its ability to remove radionuclides; to find new materials, absorbents and membranes effective in the removal of radionuclides and to issue guidelines for the treatment and disposal of radioactive wastes produced in water treatment. Radon could be removed efficiently (>95%) from domestic water supplies by both aeration and granular activated carbon (GAC) filtration. Defects in technical reliability or radon removal efficiency were observed in some aerators. The significant drawback of GAC filtration was the elevated gamma dose rates (up to 120 {mu}Sv/h) near the filter and the radioactivity of spent GAC. Aeration was found to be a suitable method for removing radon at waterworks, too. The removal efficiencies at waterworks where the aeration process was designed to remove radon or carbon dioxide were 67-99%. If the aeration process was properly designed, removal efficiencies higher than 95% could be attained. Uranium could best be removed (>95%) with strong basic anion exchange resins and radium by applying strong

Removal of radionuclides at a waterworks

International Nuclear Information System (INIS)

Gaefvert, T.; Ellmark, C.; Holm, E.

2002-01-01

A waterworks, providing several large cities in the province of Scania with drinking-water, with an average production rate of 1.3 m 3. s -1 has been studied regarding its removal capacity for several natural and anthropogenic radionuclides. The raw water is surface water from lake Bolmen which is transported through an 80 km long tunnel in the bedrock before it enters the waterworks. The method used for purification is a combination of precipitation and filtration in sand filters. Two different purification lines are at the moment in use, one using A1 2 (SO 4 ) 3 as a coagulant and one using FeC1 3 . After coagulation and flocculation the precipitation is removed and the water is passed through two different sand filters (rapid-filtration and slow-filtration). Water samples have been collected at the lake, the inlet at the waterworks, after each of the flocculation basins (A1 2 (SO 4 ) 3 and FeC1 3 ), after rapid-filtration and from the municipal distribution net. The samples have been analysed with respect to its content of uranium, thorium, polonium, radium, plutonium and caesium. (au)

Sediment studies at Bikini Atoll part 3. Inventories of some long-lived gamma-emitting radionuclides associated with lagoon surface sediments

Energy Technology Data Exchange (ETDEWEB)

Noshkin, V.E.

1997-12-01

Surface sediment samples were collected during 1979 from 87 locations in the lagoon at Bikini Atoll. The collections were made to better define the concentrations and distribution of long-lived radionuclides associated with the bottom material and to show what modifications occurred to the composition of the surface sediment from the nuclear testing program conducted by the United States at the Atoll between 1946 and 1958. This is the last of three reports on Bikini sediment studies. In this report, we discuss the concentrations and inventories of the residual long-lived gamma-emitting radionuclides in sediments from the lagoon. The gamma-emitting radionuclides detected most frequently in sediments collected in 1979, in addition to Americium-241 ({sup 241}Am) (discussed in the second report of this series), included Cesium-137 ({sup 137}Cs), Bismuth-207 ({sup 207}Bi), Europium-155 ({sup 155}Eu), and Cobalt-60 ({sup 60}Co). Other man-made, gamma-emitting radionuclides such as Europium-152,154 ({sup 152,154}Eu), Antimony-125 ({sup 125}Sb), and Rhodium-101,102m ({sup 101,102m}Rh) were occasionally measured above detection limits in sediments near test site locations. The mean inventories for {sup 137}Cs, {sup 207}Ei, {sup 155}Eu, and {sup 60}Co in the surface 4 cm of the lagoon sediment to be 1.7, 0.56, 7.76, and 0.74 TBq, respectively. By June 1997, radioactive decay would reduce these values to 1.1, 0.38, 0.62, and 0.07 TBq, respectively. Some additional loss results from a combination of different processes that continuously mobilize and return some amount of the radionuclides to the water column. The water and dissolved constituents are removed from the lagoon through channels and exchange with the surface waters of the north equatorial Pacific Ocean. Highest levels of these radionuclides are found in surface deposits lagoonward of the Bravo Crater. Lowest concentrations and inventories are associated with sediment lagoonward of the eastern reef. The quantities in

Europium(III) complex-functionalized magnetic nanoparticle as a chemosensor for ultrasensitive detection and removal of copper(II) from aqueous solution.

Science.gov (United States)

Liu, Jing; Zuo, Wei; Zhang, Wei; Liu, Jian; Wang, Zhiyi; Yang, Zhengyin; Wang, Baodui

2014-10-07

Ultrasensitive, accurate detection and separation of heavy metal ions is very important in environmental monitoring and biological detection. In this paper, a highly sensitive and specific detection method for Cu(2+) based on the fluorescence quenching of a europium(III) hybrid magnetic nanoprobe is presented. This nanoprobe can detect Cu(2+) over a wide pH range (5.0-10.0) with a detection limit as low as 0.1 nM and it can be used for detecting Cu(2+) in living cells. After the magnetic separation, the Cu(2+) concentration decreased to 1.18 ppm, which is less than the US EPA drinking water standard (1.3 ppm), and more than 70% Cu(2+) could be removed when the amount of nanocomposite 1 reached 1 mg.

Synthesis and spectral properties of europium phthalocyanine complexes

International Nuclear Information System (INIS)

Maksimova, K.N.; Bazyakina, N.L.; Kutyreva, V.V.; Suvorova, O.N.; Domrachev, G.A.

2008-01-01

Synthesis of europium monophthalocyanic complexes with thenoyltrifluroacetonate (tta) and ferrocenoyltrifluoroacetate (fta) ligands has been considered. Spectral characteristics of complexes PcEu(tta)(ttaH) and PcEu(fta)(ftaH) (Pc - phthalocyanine ligand) have been investigated. One of β-diketonate ligand is proposed to bind with europium ion covalently, and the second ligand saturates coordination sphere of europium due to donor-acceptor binding [ru

Removal of radionuclides from the water-soluble fraction of Hanford nuclear defense wastes

International Nuclear Information System (INIS)

Strachan, D.M.; Schulz, W.W.

1980-01-01

The current Hanford Waste Management Program has operated since 1968 to remove the bulk of the long-lived heat emitters /sup 90/Sr and /sup 137/Cs from stored high-level wastes. The liquid waste remaining after removal of /sup 90/Sr and /sup 137/Cs is returned to underground tanks for eventual evaporation to damp solid salt cake. Approximately 95,000 m/sup 3/ of salt cake and 49,000 m/sup 3/ of ''sludge'' will eventually accumulate in approximately 50 underground single-shell tanks. One alternative for long-term management of high-level Hanford wastes involves retrieval, after a yet-to-be determined interim storage time, conversion to more immobile forms, and terminal storage in a suitable geologic repository. Another alternative for long-term management of salt cake and residual liquid involves removing most of the long-lived radionuclides and many of the shorter-lived ones from these wastes. This paper describes conditions and results of recent hot cell tests of the complete Hanford Radionuclide Removal Process. These advanced tests, made with actual residual liquid containing large concentrations of ethylenediaminetetracetic acid (EDTA) and other organic compounds, provided a rigorous and convincing proof of the process flowsheet. 16 refs

Europium-155 in Debris from Nuclear Weapons

DEFF Research Database (Denmark)

Aarkrog, Asker; Lippert, Jørgen Emil

1967-01-01

The lithium-drifted germanium detector enables determination of europium-155 on a routine basis in environmental samples contaminated with debris from nuclear weapons. From measurements of europium-155, cesium-144, and strontium-90 in air filters collected between 1961 and 1966, the yield...

Adsorption and desorption of radionuclide europium(III) on multiwalled carbon nanotubes studied by batch techniques

International Nuclear Information System (INIS)

Songsheng Lu; Junzheng Xu; Caicai Zhang; Zhiwei Niu

2011-01-01

The adsorption of Eu(III) on multiwalled carbon nanotubes (MWCNTs) as a function of pH, ionic strength and solid contents are studied by batch technique. The results indicate that the adsorption of Eu(III) on MWCNTs is strongly dependent on pH values, dependent on ionic strength at low pH values and independent of ionic strength at high pH values. Strong surface complexation and ion exchange contribute to the adsorption of Eu(III) on MWCNTs at low pH values, whereas surface complexation and surface precipitation are the main adsorption mechanism of Eu(III) on MWCNTs. The desorption of adsorbed Eu(III) from MWCNTs by adding HCl is also studied and the recycling use of MWCNTs in the removal of Eu(III) is investigated after the desorption of Eu(III) at low pH values. The results indicate that adsorbed Eu(III) can be easily desorbed from MWCNTs at low pH values, and MWCNTs can be repeatedly used to remove Eu(III) from aqueous solutions. MWCNTs are suitable material in the preconcentration and solidification of radionuclides from large volumes of aqueous solutions in nuclear waste management. (author)

Statistical optimization of synthesis procedure and characterization of europium (III) molybdate nano-plates

Energy Technology Data Exchange (ETDEWEB)

Pourmortazavi, Seied Mahdi [Malek Ashtar University of Technology, Faculty of Material and Manufacturing Technologies, P. O. Box 16765-3454, Tehran (Iran, Islamic Republic of); Rahimi-Nasrabadi, Mehdi [Imam Hossein University, Nano Science Center, Tehran (Iran, Islamic Republic of); Fazli, Yousef [Islamic Azad University, Department of Chemistry, Faculty of Science, Arak Branch, Arak (Iran, Islamic Republic of); Mohammad-Zadeh, Mohammad [Sabzevar University of Medical Sciences, Department of Physiology and Pharmacology, School of Medicine, Sabzevar (Iran, Islamic Republic of)

2015-06-15

Europium (III) molybdate nano-plates were synthesized in this work via chemical precipitation route involving adding of europium (III) ion solution to the aqueous solution of molybdate reagent. Effects of some reaction variables such as concentrations of europium and molybdate ions, flow rate of europium reagent, and reactor temperature on the diameter of the synthesized europium (III) molybdate nano-plates were experimentally investigated by orthogonal array design. The results showed that the size of europium (III) molybdate nano-plates can be optimized by adjusting the concentrations of europium (III) and molybdate ions, as well as the reactional temperature. Europium (III) molybdate nano-plates prepared under the optimum conditions were characterized by X-ray powder diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. (orig.)

Examinations on the removal of natural radionuclides from drinking water and overview on their distribution in Austria

International Nuclear Information System (INIS)

Staubmann, K.

2002-09-01

The objective of the thesis was to give an overview about available data regarding natural radioactivity in Austrian ground and spring water and to examine the capability of membrane processes, ion exchange processes and processes for iron and manganese removal to remove natural radionuclides from drinking water. There are already Austrian-wide data existing for the activity concentrations of radon-222 in ground- and spring water, only few values are available for radium-226 (Ra-226), lead-210 (Pb-210), uranium (U) and polonium-210 up til now. From the existing data it is to be expected that in Austria only in exceptions water treatment will be necessary. The tested reverse osmosis and nanofiltration systems removed between 95.6 % and 99.8 % of Ra-226, U and Pb-210 on the average. Laboratory scale experiments for ion exchange showed an essential influence of the concurrent ions in the water on the removal of the radionuclides. With water softeners (cation exchangers) Ra-226 to more than 90 % and Pb to more than 80 % could be removed. By the use of other ones than the standard cartridge fillings for pour-through-filters (ion exchangers) the radionuclides could be removed more selectively and more effectively and the influence on the chemical composition of the water could be minimized. In a laboratory scale experiment simulating the planned treatment process at a waterwork for the removal of iron and manganese Ra-226 was removed to 61%. At the examined processes often disadvantageous side effects onto the water quality which require a subsequent treatment were observed. During the operation of the systems it should be aimed at keeping the activity in the produced waste low so that no radiation protection relevant risk starts from that. (author)

X-ray structural analysis of plasma sprayed europium oxide

Energy Technology Data Exchange (ETDEWEB)

Gorshkov, B.N.; Loskutov, V.S.; Gavrish, A.A.; Shakh, G.E.

1981-12-01

An X-ray structure microanalysis is made for europium oxide powder produced by sintering and plasmic spheroidization for plasma spraying. The technique of concern is shown not to alter chemical composition of the powder. It is stated that a rise in the plasma jet enthalpy while spraying does not result in dissociation of europium oxide and its interaction with the plasma flux. The coating (to 15.2 kWxs/g) is found to have only a high-temperature (monoclinic) europium oxide phase and there appears a low-temperature (cubic) phase with a subsequent increase in the enthalpy. The plasma jet enthalpy increasing the grain size and the crystal lattice c parameter of the sprayed europium oxide are shown to decrease; the a parameter reduces with an enthalpy growth to 16.2 kW s/g and then smoothly increases with the enthalpy further growth. It is noticed that the europium oxide coating does not interact with an aluminium D16 alloy substrate.

Solubility and first hydrolysis constants of europium at different ionic strength and 303 K

International Nuclear Information System (INIS)

Ramirez-Garcia, J.J.; Jimenez-Reyes, M.; Lopez-Gonzalez, H.; Autonoma Metropolitana-Iztapalapa Univ., Mexico City; Solache-Rios, M.; Fernandez-Ramirez, E.; Centro Interamericano de Recursos del Agua, Toluca; Rojas-Hernandez, A.

2003-01-01

The solubility of europium at 0.02M, 0.1M and 0.7M NaClO 4 ionic strength solutions was determined by a radiometric method and pEu s -pC H diagrams were obtained. Hydrolysis constants were also determined at the same ionic strengths by pH titration and the values found were log *β 1 -7.68±0.11, -8.07±0.10 and -8.20±0.11. The log K sp values were -23.5±0.2, -22.7±0.2 and -21.9±0.2 for 0.02M, 0.1M and 0.7M NaClO 4 ionic strengths, respectively, at 303 K under CO 2 -free conditions and the extrapolated value at zero ionic strength was log K sp 0 = -24.15. The working pC H ranges for the calculation of the hydrolysis constants were selected from the pEu s -pC H diagrams in the region where precipitation of europium oxide or hydroxide was less than 20%. Europium removal from aqueous solutions with zeolites was explored. (author)

Removal of heavy metals and radionuclides by seeded magnetic filtration

International Nuclear Information System (INIS)

Bibler, J.P.; Norrell, G.; Hemmings, R.L.; Bradbury, D.; Dunn, M.J.; Kalinauskas, G.L.

1991-01-01

Removal of traces of heavy metal or radionuclide contamination from solution at high flow rate presents a considerable technical challenge. Low flow methods of treatment such as particle gravity settling require expensive large volume equipment, whereas traditional methods of filtration can cause significant energy costs. Magnetic filtration can be used to provide a low cost method of solid-liquid separation at high flow rate, provided contaminants can be selectively bound to a magnetic solid particle. This paper describes the use of such selective magnetic particles made up of inorganic particles coupled with organic polymers

Resonance ionization scheme development for europium

Energy Technology Data Exchange (ETDEWEB)

Chrysalidis, K., E-mail: katerina.chrysalidis@cern.ch; Goodacre, T. Day; Fedosseev, V. N.; Marsh, B. A. [CERN (Switzerland); Naubereit, P. [Johannes Gutenberg-Universität, Institiut für Physik (Germany); Rothe, S.; Seiffert, C. [CERN (Switzerland); Kron, T.; Wendt, K. [Johannes Gutenberg-Universität, Institiut für Physik (Germany)

2017-11-15

Odd-parity autoionizing states of europium have been investigated by resonance ionization spectroscopy via two-step, two-resonance excitations. The aim of this work was to establish ionization schemes specifically suited for europium ion beam production using the ISOLDE Resonance Ionization Laser Ion Source (RILIS). 13 new RILIS-compatible ionization schemes are proposed. The scheme development was the first application of the Photo Ionization Spectroscopy Apparatus (PISA) which has recently been integrated into the RILIS setup.

Study of radionuclides speciation with biological molecules of interest by spectrometric techniques; Etude de la speciation des radionucleides avec les molecules d'interet biologique par approche spectrometrique

Energy Technology Data Exchange (ETDEWEB)

Lourenco, V

2007-07-15

Mechanisms of complexation and accumulation of the radionuclides at the cellular and molecular level are complex and poorly known because the studies on these subjects are scarce. Within the framework of this thesis, we studied the interactions of these cations with biological molecules of interest. We chose to focus on an actinide: uranium (VI) as well as europium as an analogue of trivalent actinides. The selected biological molecules are the phyto-chelatins: their role is to protect cells against intrusions from nonessential heavy metals (thus toxic). These proteins are likely to be implied in the mechanisms of sequestration of radionuclides in living organisms. However, their structure is complex, this is why, in order to better include/understand their reactivity, we extended our studies to lower entities which constitute them (amino acid: glycine, glutamic acid and cysteine; polypeptides: glutathione reduced and oxidized forms). In particular, we determined solution speciation (stoichiometry, structure) as well as the complexing constants associated with the formation with these species. These studies were undertaken by Time Resolved Laser induced Fluorescence (TRLIF), Electro-Spray-Mass Spectrometry (ES-MS), Nuclear Magnetic Resonance (NMR), Fourier Transform Infra-Rouge spectroscopy (FTIR) and Extended X-ray Absorption Fine Structure Spectroscopy (EXAFS).The determination of the complexation constants enabled us to conclude that the complexing capacity of these molecules with respect to radionuclides was moderate (log{sub 10}K{sub 1} {<=} 3, pH 3 or 6), the formed species are mononuclear with only one ligand molecule (1:1). The interaction is performed via oxygenated (hard) groups. The direct complexation of europium with phyto-chelatins at acidic pH was studied jointly by TRLIF and ES-MS. The complexing capacity of these molecules is much higher than that of GSH from which they result. The interaction of europium with metallothioneins is, on the contrary

Europium sorption on zirconia at elevated temperatures: experimental study and modeling

International Nuclear Information System (INIS)

Eglizaud, N.; Catalette, H.

2005-01-01

Full text of publication follows: Direct disposal of spent nuclear fuel in deep underground repository is being considered by several countries. The waste package maintains an elevated temperature for thousands of years. As sorption is one of the main phenomenon limiting the dispersion of radionuclides in the environment, it has to be studied at elevated temperatures. Zirconia is an oxide produced by cladding oxidation which is suspected in the near field of a nuclear repository. It then could possibly be in contact with waste elements as Europium (III), the sorption of which is therefore studied on zirconia. Experiments were performed by the batch method at a solid/liquid ratio of 10 g.L-1. The sorption edges were recorded in the pH-range from 2 to 10 at 2.10 -5 mol.L -1 Eu(NO 3 ) 3 (I = 0.1 mol.L -1 KNO 3 ). An over-pressure device in an autoclave with an incorporated filtering system allowed the experiments, carbonate free, at 25 deg. C, 50 deg. C, 80 deg. C, 120 deg. C and 150 deg. C and in situ pH measurements. Filtrates were analyzed by the ICP-AES method. Sorption isotherms show an increase in the sorption phenomenon when the temperature raises. The half sorption pH decreases from 7 at 25 deg. C to 3,6 at 150 deg. C. The distribution coefficients that were obtained at elevated temperatures enriched the databases of integrated performance assessment codes. Raw data were modeled with the surface complexation theory using the double layer model (DLM). Several possible surface complexes were examined and discussed, taking into account aqueous hydrolyzed and precipitated species of Europium. A good agreement between experimental values and modeled isotherms was found at all studied temperatures. Results were consistent with a bidentate complex formed by Europium (III) on the zirconia surface. Associated formation constants were then determined with the geochemical computer code CHESS. (authors)

Study of the europium behavior in aqueous media

International Nuclear Information System (INIS)

Fernandez R, E.; Jimenez R, M.; Solache R, M.; Martinez M, V.

1999-01-01

Europium as waste can produce a pollution problem in water that is in contact with it, what would has a heavy environmental impacts, because of the possibilities of diffusion of these wastes from their place of confinement or storage until the geo and biosphere. The solution of such problem requires of a lot of knowledge over the behavior of several chemical elements such as europium in aqueous solutions. In this work it was used a low ion force (0.02 M). The data set will allow extrapolate the hydrolytic behavior of europium in too much minors ion force media, such as the ground waters, including in ion force zero

The effect of organics on the sorption of strontium, caesium, iodine, neptunium, uranium and europium by glacial sand

International Nuclear Information System (INIS)

Haigh, D.; Higgo, J.J.W.; Williams, G.M.; Hooker, P.J.; Ross, C.A.M.; Falck, W.E.; Allen, M.A.; Warwick, P.

1991-01-01

This study has been undertaken within the Commission of the European Communities MIRAGE II program on the determination of radionuclides in the geosphere. Preliminary batch sorption experiments have been carried out to study the behaviour of strontium, caesium, iodine, europium and uranium in a glacial sand-groundwater system. The effect of (i) the presence or absence of natural organic material and (ii) the addition of increasing quantities of EDTA or acetate on the distribution ratios was determined. In some cases speciation modelling was used as an aid to designing the experiments and interpreting the results. The aim of this work was to select suitable tracers for use in field experiments at Drigg. Cumbria and the results are intended to aid the design of future experiments rather than to provide a complete analysis of the radionuclide-organic interactions. 11 tabs., 49 refs

Sorption behavior of cesium, cobalt and europium radionuclides onto hydroxyl magnesium silicate

Energy Technology Data Exchange (ETDEWEB)

Hamed, Mostafa M.; Holiel, M.; Ahmed, I.M. [Atomic Energy Authority, Cairo (Egypt). Hot Laboratories and Waste Management Center

2016-07-01

The radioactive wastes from different activities have to be safely disposed of and isolated from the human environment. The retardation of radioactive materials by designed barriers is originally controlled by the sorption ability of the mineral compositions. In this work, a naturally available mineral composite, a hydroxyl magnesium silicate (HMS) was investigated as potential natural inorganic sorbent for the retention of long-lived radionuclides ({sup 134}Cs, {sup 60}Co and {sup 152+154}Eu) from aqueous solutions. The factors affecting the sorption process, such as contact time and pH were evaluated. Furthermore X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), differential thermal and thermogravimetry analyses (DTA/TGA) measurements were examined in order to assess the physicochemical properties of the magnesium silicate mineral. Langmuir and Freundlich isotherms fitted the result s substantially better than the Flory-Huggins isotherm and the sorption was found to follow pseudo-first order kinetic model. The proposed mineral has been successfully applied for the sorption of {sup 134}Cs, {sup 60}Co and {sup 152+154}Eu radionuclides from real radioactive waste. The results indicated that about 97.4-99% of {sup 134}Cs, {sup 60}Co and {sup 152+154}Eu radionuclides were efficiently retained onto the HMS mineral. Based on the results obtained, it can be concluded that the HMS mineral is an economic and efficient retaining material for environmental hazardous migration and/or leakage of some radionuclides such as {sup 134}Cs, {sup 60}Co and {sup 152+154}Eu and trivalent actinide ({sup 241}Am, {sup 242m}Am and {sup 243}Am) ions. Therefore, this study could be used as a starting point to establish and consider that mineral as an engineered barrier around the disposal facilities at the nuclear activity centres.

Enhancement in red emission at room temperature from europium doped ZnO nanowires by 1,10 phenanthroline-europium interface induced resonant excitations

Directory of Open Access Journals (Sweden)

Soumen Dhara

2017-02-01

Full Text Available We show that europium doped ZnO nanowires after surface modification with organic ligand, 1,10 phenanthroline (phen leads to strong red emission at 613 nm which is a characteristic emission from the atomic levels of Eu3+. Surface modification with phen leads to formation of phenanthroline-europium interface on the surface of the nanowires due to attachment of Eu3+ ions. After an optimized surface modification with phen, intensity of both the UV emission (band edge and red emission improved by two orders of magnitude at room temperature. We observed multiple energy transfer pathways to the energy levels of Eu3+ ions through the phenanthroline-europium interface, which found to be very effective to the significant enhancement of emission from the dopant Eu3+. This study shows a new insight in to the energy transfer process from phen to the europium doped ZnO system.

Preparation and spectral properties of europium hydrogen squarate microcrystals

Science.gov (United States)

Kolev, T.; Danchova, N.; Shandurkov, D.; Gutzov, S.

2018-04-01

A simple scheme for preparation of europium hydrogen squarate octahydrate microcrystals, Eu(HSq)3·8H2O is demonstrated. The microcrystalline powders obtained have a potential application as non-centrosymmetric and UV radiation - protective hybrid optical material. The site-symmetry of the Eu - ion is C2V or lower, obtained from diffuse reflectance spectra. The formation of europium hydrogen squarate is supported by IR - spectroscopy, UV-vis spectroscopy, chemical analysis and X-ray diffraction. A detailed analysis of the UV-vis and IR spectra of the micropowders prepared is presented. The reaction between europium oxide and squaric acid leads to formation of microcrystalline plate-like crystals of europium hydrogen squarate Eu(HSq)3·8H2O, a non-centrosymmetric hybrid optical material with a potential application as UV radiation - protective coatings.

Europium polyoxometalates encapsulated in silica nanoparticles - characterization and photoluminescence studies

Energy Technology Data Exchange (ETDEWEB)

Neves, Cristina S.; Granadeiro, Carlos M.; Cunha-Silva, Luis; Eaton, Peter; Balula, Salete S.; Pereira, Eulalia [REQUIMTE/Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto (Portugal); Ananias, Duarte [CICECO, Departamento de Quimica, Universidade de Aveiro (Portugal); Gago, Sandra [REQUIMTE, Departamento de Quimica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Monte de Caparica (Portugal); Feio, Gabriel [CENIMAT/I3N, Departamento de Ciencia dos Materiais, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Monte de Caparica (Portugal); Carvalho, Patricia A. [ICEMS/Departamento de Bioengenharia, Instituto Superior Tecnico, Lisboa (Portugal)

2013-06-15

The incorporation of europium polyoxometalates into silica nanoparticles can lead to a biocompatible nanomaterial with luminescent properties suitable for applications in biosensors, biological probes, and imaging. Keggin-type europium polyoxometalates Eu(PW{sub 11}){sub x} (x = 1 and 2) with different europium coordination environments were prepared by using simple methodologies and no expensive reactants. These luminescent compounds were then encapsulated into silica nanoparticles for the first time through the water-in-oil microemulsion methodology with a nonionic surfactant. The europium polyoxometalates and the nanoparticles were characterized by using several techniques [FTIR, FT-Raman, {sup 31}P magic angle spinning (MAS) NMR, and TEM/energy-dispersive X-ray spectroscopy (TEM-EDS), AFM, dynamic light scattering (DLS), and inductively coupled plasma MS (ICP-MS) analysis]. The stability of the material and the integrity of the europium compounds incorporated were also examined. Furthermore, the photoluminescence properties of the Eu(PW{sub 11}){sub x} rate at SiO{sub 2} nanomaterials were evaluated and compared with those of the free europium polyoxometalates. The silica surface of the most stable nanoparticles was successfully functionalized with appropriate organosilanes to enable the covalent binding of oligonucleotides. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Physico-chemical forms of natural radionuclides in drilled well waters and their removal by ion exchange

International Nuclear Information System (INIS)

Vaaramaa, K.

2003-01-01

Appreciable concentrations of natural uranium and its daughter radionuclides may occur in drinking water obtained from drilled wells when the bedrock contains these nuclides. Effective methods are needed to remove these radionuclides. A wide range of ion exchange materials, both organic and inorganic, were evaluated for the removal of 234,238 U, 226 Ra, 210 Po and 210 Pb from ground waters. Screenin tests were carried out, in which distribution coefficients (KD) were determined for the ion exchangers. The ion exchangers that gave the highest KD's were tested in column-mode experiments for the removal of the radionuclides from drilled well water. The most efficient exchanger for the removal of U from neutral and slightly alkaline waters was the strong base anion resin. The chelating aminophosphonate resin removed uranium very efficiently from slightly acidic water. As well, it was an efficient exchanger for the removal of toxic and harmful transition metals from drilled well waters. The strong and weak acid cation resins and zeolite A removed radium most efficiently. Large fractions of the total activity of polonium and lead were found to adsorb on equipment in the ion exchange studies. In investigation of this, the well waters were filtered through membranes to determine the soluble and particle-bound forms of 234,238 U, 226 Ra, 210 Po and 210 Pb. Eight of the waters were of Ca type and two were of Na-Cl type. Some of the waters also had high concentrations of Fe, Mn and humic substances. Uranium was present entirely in soluble form, probably as uranyl ion in soluble carbonate complexes. 226 Ra was in soluble form in the waters with low concentrations of Fe and Mn, but 10% of the total radium activity was bound to particles in Fe-Mn-rich waters. The speciation of Po is complex in natural waters; polonium was present in both soluble and particle-bound forms. A correlation was observed between the fractions of particle-bound 210 Po and the concentrations of iron in

Europium ion as a probe for binding sites to carrageenans

International Nuclear Information System (INIS)

Ramos, Ana P.; Goncalves, Rogeria R.; Serra, Osvaldo A.; Zaniquelli, Maria Elisabete D.; Wong, Kenneth

2007-01-01

Carrageenans, sulfated polysaccharides extracted from red algae, present a coil-helix transition and helix aggregation dependence on the type and concentration of counterions. In this study, we focus attention on a mixed valence counterion system: Eu 3+ /Na + or K + with different gel-forming carrageenans: kappa, iota, and kappa-2. Results of stationary and time-dependent luminescence showed to be a suitable tool to probe ion binding to both the negatively charged sulfate group and the hydroxyl groups present in the biopolymer. For lower europium ion concentrations, a single longer decay emission lifetime was detected, which was attributed to the binding of europium ion to the carrageenan sulfate groups. An additional decay ascribed to europium binding to hydroxyl groups was observed above a threshold concentration, and this decay was dependent on the carrageenan charge density. Symmetry of the europium ion microenvironment was estimated by the ratio between the intensities of its emission bands, which has been shown to depend on the concentration of europium ions and on the specificity of the monovalent counterion bound to the carrageenan

Europium ion as a probe for binding sites to carrageenans

Energy Technology Data Exchange (ETDEWEB)

Ramos, Ana P.; Goncalves, Rogeria R.; Serra, Osvaldo A. [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo 14040-901 (Brazil); Zaniquelli, Maria Elisabete D. [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo 14040-901 (Brazil)], E-mail: medzaniquelli@ffclrp.usp.br; Wong, Kenneth [Laboratorio de Fisico-Quimica, Centro de Pesquisas de Paulinia, Rhodia Brasil, Paulinia, Sao Paulo (Brazil)

2007-12-15

Carrageenans, sulfated polysaccharides extracted from red algae, present a coil-helix transition and helix aggregation dependence on the type and concentration of counterions. In this study, we focus attention on a mixed valence counterion system: Eu{sup 3+}/Na{sup +} or K{sup +} with different gel-forming carrageenans: kappa, iota, and kappa-2. Results of stationary and time-dependent luminescence showed to be a suitable tool to probe ion binding to both the negatively charged sulfate group and the hydroxyl groups present in the biopolymer. For lower europium ion concentrations, a single longer decay emission lifetime was detected, which was attributed to the binding of europium ion to the carrageenan sulfate groups. An additional decay ascribed to europium binding to hydroxyl groups was observed above a threshold concentration, and this decay was dependent on the carrageenan charge density. Symmetry of the europium ion microenvironment was estimated by the ratio between the intensities of its emission bands, which has been shown to depend on the concentration of europium ions and on the specificity of the monovalent counterion bound to the carrageenan.

Retention of barium and europium radionuclides from aqueous solutions on ash-based sorbents by application of radiochemical techniques.

Science.gov (United States)

Noli, Fotini; Kapnisti, Maria; Buema, Gabriela; Harja, Maria

2016-10-01

New materials were synthesized for application in sorption of radionuclides from aqueous solutions. The elaboration was performed by conversion of power plant ash using the hydrothermal method under optimum experimental conditions. Sodalite, Na-Y, and analcime were formed from ash precursor during the treatment, exhibiting thermal stability as revealed by the characterization by X-ray diffraction (XRD) and thermogravimetric differential thermal analysis (TG-DTA). The Brunauer-Emmett-Teller (BET) surface area and pore volume were determined and they presented higher values than plant ash. The ability of the new products to retain Ba and Eu radionuclides was studied in aqueous solutions using (133)Ba and (152)Eu as tracers and γ-ray spectroscopy under batch experiments. The experimental data were modeled by the Langmuir and Freundlich equations, whereas sorption kinetics measurements were performed at 293, 308, and 323K and thermodynamic parameters were calculated. The release of the sorbed ions into the environment was also tested by leaching experiments. The results of these tests indicated that the synthesized materials are very efficient in removing the aforementioned metals from aqueous solutions and can be considered as potential low-cost sorbents in nuclear waste management. Copyright © 2016 Elsevier Ltd. All rights reserved.

Therapy for incorporated radionuclides: scope and need

International Nuclear Information System (INIS)

Smith, V.H.

1981-03-01

In the United States the recent termination of funding for research on therapy for incorporated radionuclides has virtually halted progress on improved or new agents and procedures for removing radioactivity from the body. Research was eliminated, but is still needed on new removal agents, improved delivery system, in vitro test systems, and the toxicology of treatments. For many radionuclides, no adequate therapy exists. The relationship between radionuclide removal and reduction in cancer risk is still unanswered. Without proper research support, needed improvements in the treatment for incorporated radionuclides in the US are uncertain

SEPARATION OF EUROPIUM FROM OTHER LANTHANIDE RAE EARTHS BY SOLVENT EXTRACTION

Science.gov (United States)

Peppard, D.F.; Horwitz, E.P.; Mason, G.W.

1963-02-12

This patent deals with a process of separating europium from other lanthanides present in aqueous hydrochloric or sulfuric acid solutions. The europium is selectively reduced to the divalent state with a divalent chromium salt formed in situ from chromium(III) salt plus zinc amalgam. The other trivalent lanthanides are then extracted away from the divalent europium with a nitrogen-flushed phosphoric acid ester or a phosphonic acid ester. (AEC)

Property of a CZT semiconductor detector for radionuclide identification

International Nuclear Information System (INIS)

Chun, Sung-Dae; Park, Se-Hwan; Ha, Jang Ho; Kang, Sang Mook; Lee, Dong Hoon; Kim, Yong Kyun; Cho, Yun Ho; Kim, Jong Kyung; Hong, Duk-Geun

2008-01-01

Compound semiconductors of high Z value material have been studied intensively for X-ray and γ-ray spectroscopy at room temperature. CdZnTe has wide band gap energy as 1.6 eV and can provide high quantum efficiency with reasonably good energy resolution at room temperature. This study is aimed at determining radionuclide analysis ability by measuring energy resolution of CZT detector which will be applied at nuclear material identification purpose. For experiment we used a CZT detector (5 x 5 x 5 mm 3 ) which is manufactured by eV Products. We have performed our measurement at varied temperatures similar to the outdoor environment for the investigation about temperature dependence of energy resolution and peak centroid fluctuation of CZT detector by using gas cooling and Peltier cooling methods. In order to test radionuclide identification we used various radionuclide samples; plutonium, europium and other standard sources. Pulse height spectra were obtained by standard electronics which consists of a preamplifier, a shaping amplifier, and a multi-channel analyzer. (author)

Organophosphate Nerve Agent Detection with Europium Complexes

Directory of Open Access Journals (Sweden)

Jake R. Schwierking

2004-01-01

Full Text Available We explore the detection of paraoxon, a model compound for nonvolatile organophosphate nerve agents such as VX. The detection utilizes europium complexes with 1,10 phenanthroline and thenoyltrifluoroacetone as sensitizing ligands. Both europium luminescence quenching and luminescence enhancement modalities are involved in the detection, which is simple, rapid, and sensitive. It is adaptable as well to the more volatile fluorophosphate nerve agents. It involves nothing more than visual luminescence observation under sample illumination by an ordinary hand-held ultraviolet lamp.

Retention of Radionuclides in Halite and Anhydrite

DEFF Research Database (Denmark)

Carlsen, Lars; Platz, O.

1986-01-01

The interaction between a series of radionuclides, comprising **1**3**4Cs** plus , **8**5Sr**2** plus , **6**0Co**2** plus , **1**5**4Eu**3** plus , **2**4**1Am**3** plus , and **9**9Tc (as TcO//4** minus ) and halite (NaCl) and anhydrite (CaSO//4), respectively, has been investigated. It appears...... for europium and americium, respectively. Impuritites in the halite, such as hematite or anhydrite strongly increase the sorption efficiency. In these cases also cobalt, and to a minor extent cesium and strontium, was found to be sorbed. Anhydrite was found to sorb all metal cations studied. The sorption...

APW research of europium monochalcogenides. 1

International Nuclear Information System (INIS)

Farberovich, O.V.; Vlasov, S.V.

1981-01-01

The augmented plane wave method (APW) is used for a theoretical study of the electron properties of europium monochalcogenides. Spin-polarized energy band calculations of the ferromagnetic EuO, EuS, and EuSe explain qualitatively the exchange interactions therein. Based on the APW data in the frame of perturbation theory the Coulomb electron-electron interaction at the 4f shell of europium is taken into account for EuO and EuS. The band structures and the multiplet terms of the f 6 d and 3d 9 4f 8 excited states gives a new interpretation of a known experimental spectra for these compounds. (author)

Method of separating short half-life radionuclides from a mixture of radionuclides

Science.gov (United States)

Bray, L.A.; Ryan, J.L.

1999-03-23

The present invention is a method of removing an impurity of plutonium, lead or a combination thereof from a mixture of radionuclides that contains the impurity and at least one parent radionuclide. The method has the steps of (a) insuring that the mixture is a hydrochloric acid mixture; (b) oxidizing the acidic mixture and specifically oxidizing the impurity to its highest oxidation state; and (c) passing the oxidized mixture through a chloride form anion exchange column whereupon the oxidized impurity absorbs to the chloride form anion exchange column and the {sup 229}Th or {sup 227}Ac ``cow`` radionuclide passes through the chloride form anion exchange column. The plutonium is removed for the purpose of obtaining other alpha emitting radionuclides in a highly purified form suitable for medical therapy. In addition to plutonium, lead, iron, cobalt, copper, uranium, and other metallic cations that form chloride anionic complexes that may be present in the mixture are removed from the mixture on the chloride form anion exchange column. 8 figs.

The application of polyelectrolytes to improve liquid radwaste treatment system radionuclide removal efficiency

International Nuclear Information System (INIS)

Homyk, W.A.; Spall, M.J.; Vance, J.N.

1990-01-01

At nuclear plants, miscellaneous waste water treated in the liquid radwaste processing system contains a significant fraction of suspended particulate materials ranging in size from a few microns down to the submicron region. The fewer particles that typically exist as colloids are generally negatively charged by virtue of inorganic and organic anions absorbed onto the particle surfaces. Because many of the radionuclides exist as colloids and resist agglomeration and settling they are not easily removed by mechanical filtration or ion exchange processes. The colloidal materials will easily pass through most filters with conventional pore size ratings and through most ion exchange media. This leads to poor decontamination Factors (dFs) and higher radionuclide releases to the environment. A laboratory-scale testing program was conducted at Indian Point Unit No. 2 to determine the effectiveness of the use of organic polyelectrolytes to destabilize colloidal suspensions in liquid radwaste. Destabilizing colloidal suspensions will improve the removal efficiencies of the suspended material by typical filtration and ion exchange processes. The increased removal efficiencies will provide increased dFs in the liquid radwaste treatment system. The testing focused on identifying the specific organic polyelectrolytes and the associated dosages which would be effective in destabilizing the colloidal suspensions on actual waste water samples. The testing also examined the filtration characteristics of the water source to determine filter parameters such as: body feed material, body feed dosages, specific flow rates, etc., which would provide the basis for the design of filtration systems for these applications. The testing effort and the major conclusions from this investigation are given. 4 refs., 8 figs., 2 tabs

Removal of radionuclides by reverse osmosis using a cellulose acetate membrane, (2)

International Nuclear Information System (INIS)

Nishimaki, Kenzo; Koyama, Akio; Saji, Minoru; Tutui, Tenson.

1990-01-01

Experiments were performed on the removal of radionuclides from radioactive liquid waste by reverse osmosis using asymmetric cellulose acetate membranes. In previous papers, we reported such removal properties as the dependence on solute concentration and the influence of co-existing material. In this paper we performed experiments on some separation properties, especially on the formation and the disappearance of concentration polarization layer of membrane surface. These experiments are necessary for the theoretical explanation of findings shown in previous papers. Concentration polarization layer is formed on the surface of the membrane, when pressurized feed solution is not stirred during reverse osmosis operation. This layer grows with elapsed time and reaches the equilibrium. The thickness of this concentration polarization layer and solute concentrations in this layer are calculated by a simple model. The formation and disappearance of this layer are experimented with intermittent stirring. The influence of intensity of stirring on the formation of concentration polarization layer is observed. These are important information on property of membrane for removing solute by reverse osmosis. (author)

Sulfur, cobalt and europium activation from the A-bombs in Japan

International Nuclear Information System (INIS)

Gritzner, M.L.; Egbert, S.D.; Woolson, W.A.

1987-01-01

Comparisons are made between calculations and measurements of in-situ sulfur, cobalt, and europium activation by neutrons at Hiroshima and Nagasaki to check the validity of the neutron sources and transport air-over-ground used in the new Dosimetry System 1986 (DS86). Europium and cobalt are activated by epithermal/thermal neutrons. The sulfur activation has an effective threshold around 2 MeV. Comparisons of sulfur activation at Hiroshima, which necessitate considering the tilt and heading of the cylindrically shaped Little Boy bomb, confirm the high energy neutron portion of the source relevant to sulfur activation. The europium and cobalt activation calculations tend to be higher than the measurements for ground ranges within 300 m and lower than the measurements beyond 700 m. Thus, the cobalt and europium measurements do not validate the source or the transport, embodied in DS87, for those neutrons relevant to europium and cobalt activation. Presently, it is unresolved as to whether the discrepancy can be explained as a problem in the measurements, in their interpretation, or as a problem in the calculations due to the source neutrons and/or their transport from source to the sample site

Soluble dendrimers europium(III) β-diketonate complex for organic memory devices

International Nuclear Information System (INIS)

Wang Binbin; Fang Junfeng; Li Bin; You Han; Ma Dongge; Hong Ziruo; Li Wenlian; Su Zhongmin

2008-01-01

We report the synthesis of a soluble dendrimers europium(III) complex, tris(dibenzoylmethanato)(1,3,5-tris[2-(2'-pyridyl) benzimidazoly]methylbenzene)-europium(III), and its application in organic electrical bistable memory device. Excellent stability that ensured more than 10 6 write-read-erase-reread cycles has been performed in ambient conditions without current-induced degradation. High-density, low-cost memory, good film-firming property, fascinating thermal and morphological stability allow the application of the dendrimers europium(III) complex as an active medium in non-volatile memory devices

Synthesis of samarium, europium and ytterbium acetylenides

International Nuclear Information System (INIS)

Bochkarev, M.N.; Fedorova, E.A.; Glushkova, N.V.; Protchenko, A.V.; Druzhkov , O.N.; Khorshev, S.Ya.

1995-01-01

Ethynyl complexes of samarium, europium and ytterbium were prepared by interaction of naphthalinides of metals with acetylene in tetrahydrofuran. The compounds are isolated in the form of dark-coloured pyrophore powders. Data of magnetic measurements suggest that in the course of the reaction Sm(2) is oxidized completely to Sm(3), Yb(2) transforms into Yb(3) partially, whereas europium preserves its initial bivalent state. Hydrolysis of the compounds prepared provides acetylene, ethylene, ethane and hydrogen which indicates the presence of acethylenide Ln 2 C 2 and hydride LnH groupings (Ln = Sm, Eu, Yb). 9 refs., 2 tabs

Preparation of 1 Ci of europium 155 without carrier; Une methode de production d'europium 155 sans entraineur au niveau du curie

Energy Technology Data Exchange (ETDEWEB)

Falconi, N; Radicella, R [Commissariat a l' Energie Atomique, Dir. des Materiaux et Combustibles Nucleaires, Saclay (France). Centre d' Etudes Nucleaires

1968-07-01

High activity 'point' sources of {sup 155}Eu are used for medical and industrial applications. For this purpose we have studied a method of obtaining I Ci of carrier free {sup 155}Eu, with a solid residue smaller than 5 mg per Ci. In order to separate the {sup 155}Eu from several grams of a {sup 154}Sm enriched target we propose a procedure which is based on the work of Bouissieres and David, Onstott, and Takekoshi et al. The separation is carried out by electrolysis on a mercury cathode followed by purification on ion exchange resin. The yields of the europium separation and target recovery are 80 per cent and 90 per cent respectively. The time required for the procedure is three days. (authors) [French] L'obtention de sources ponctuelles de haute activite d'europium-l55 est interessante tant pour des usages medicaux qu'industriels. Nous avons cherche le moyen de preparer en une seule fois, une solution d'un curie d'europium-155 sans entraineur presentant un extrait sec inferieur a 5 mg par curie. En se basant sur des travaux de Bouissieres et Davis, d'Onstott, et de Takekoshi et coll., nous avons mis au point une methode permettant de separer l'europium-155 de sa cible de samarium enrichi en {sup 154}Sm par une electrolyse sur cathode de mercure suivie d'une purification sur resine echangeuse d'ions. Les rendements chimiques de separation de l'europium et de recuperation de la cible de samarium enrichi sont respectivement de 80 pour cent et 90 pour cent. La duree de l'operation est de 3 jours. (auteurs)

Gamma-induced radiation polymerization of kaolin composite for sorption of lanthanum, europium and uranium ions from low-grade monazite leachate

International Nuclear Information System (INIS)

Metwally, S.S.; Hassan, R.S.; El-Masry, E.H.; Borai, E.H.

2018-01-01

Gamma radiation polymerization method was used for the modification of kaolin to produce (poly acrylamide-acrylic acid)-Kaolin (PAM-AA-K). Monazite ore is one of the main resources of uranium and lanthanide elements, therefore, this work focused on sorption of uranium, lanthanum and europium ions from low grade monazite leachate. The removal percent for Eu 3+ , La 3+ and UO 2 2+ are 94.6, 91.6 and 73.4%, respectively. Monolayer capacity of Eu 3+ , La 3+ and UO 2 2+ were found to be 54.64, 45.87 and 37.59 mg/g, respectively. The sorption mechanism of lanthanum and europium ions on PAM-AA-K composite mainly takes place as Ln(OH) 2+ , and for uranium as uranyl ion, UO 2 2+ . (author)

Synthesis and characterization of europium aluminophosphate

International Nuclear Information System (INIS)

Araujo, A.S.; Diniz, J.C.; Silva, A.O.S.

1998-01-01

Full text: Aluminophosphate molecular sieves (ALPO) represents a class of materials formed by AlO 2+ and PO 2- tetrahedra linked together through b the oxygen atom. The incorporation of metal cations, specifically rare earths, in the ALPO matrix, gives rise to generation of new materials that can be used as acid catalysts in chemical processes. In this work, it was synthesized hydrothermally a molecular sieve type Eu-ALPO-11, starting from an hydrated alumina (pseudobohemite), phosphoric acid solution, europium chloride, water, and di-isopropylamine (DIPA) as organic template. The gel of synthesis presented the following composition: 1.0 DIPA: 0.05 Eu 2 O 3 :0.95 Al 2 O 3 : 1.0 P 2 O 5 : 80 H 2 O The hydrogel was autoclaved at 170 deg C for a period of 3 days. After that the obtained solid was filtered, washed, dried and calcined at 500 deg C to remove the template. The sample was characterized by several physico-chemical methods, such a atomic absorption, FT-IR spectroscopy, X-ray diffraction, thermal analysis, scanning electron microscopy. Its spectroscopic properties was investigated by europium luminescence. The physico-chemical characterization of the Eu-ALPO-11 showed very good crystallinity, with AEL structure, and orthorhombic symmetry. Also, the material presents excellent thermal stability, with no structural collapse until 950 deg C. Through the luminescence spectra in the visible region, it was observed that the emission of the Eu 3+ is strongly influenced by the increasing of the 5d0 7f0 transition (Electric Dipole), as compared to the 5d0 7f1 transition (Magnetic Dipole) between the levels of 4f configuration perturbed by the crystalline field. The ED/MD ratio to the as synthesized sample was ca. 2.1, against ca. 1.1 relative to the calcined sample. The FT-IR spectra presented well defined absorption bands relative to Al-O and P-O bonds, of the structural internal tetrahedra (IT) and external links (EL): 1250- 950 cm -1 , symmetric stretching due to

Removal of cobalt and europium radioisotopes using activated carbon prepared from apricot stones

International Nuclear Information System (INIS)

Daifullah, A.A.M.; Moloukhia, H.

2002-01-01

the phenomena of cobalt and europium sorption by activated carbon from aqueous solution was studied. Activated carbon prepared from locally available agricultural wastes; apricot stones; was used. The prepared carbon was characterized using different techniques. The chemical nature of the surface of the activated carbon was also studied. Experimental studies were conducted to evaluate and optimize the various process variables i.e. equilibrium time, carbon dose, solution ph and the presence of competitive. Optimal conditions for the sorption of the radioisotopes have been identified. The sorption isotherm of Freundlich was the best fitting for the concentration range studied. Interference of oxalic acid, EDTA and phenol molecules were discussed. Percentages desorption of both acid, EDTA and phenol using bi-distilled water and IMHCI was determined. The data suggest the possible use of activated carbon of apricot stone (ACAS) for the concentration of these cations

On the existence of europium aluminum oxynitrides with a magnetoplumbite or beta-alumina type structure

NARCIS (Netherlands)

Hintzen, H.T.J.M.; Hanssen, R.; Jansen, S.R.; Metselaar, R.

1999-01-01

In the literature confusion exists concerning the structure type, the valence of europium, and the amount of nitrogen incorporation of the compound europium aluminum oxynitride. By using X-ray diffraction and luminescence measurements, we show that europium aluminum oxynitride has the

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

Energy Technology Data Exchange (ETDEWEB)

Kani, Yuko; Kamosida, Mamoru; Watanabe, Daisuke [Hitachi Research Laboratory, Hitachi, Ltd., 7-2-1 Omika-cho, Hitachi, Ibaraki, 319-1221 (Japan); Asano, Takashi; Tamata, Shin [Hitachi Works, Hitachi-GE Nuclear Energy, Ltd. (Japan)

2013-07-01

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 the 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

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

International Nuclear Information System (INIS)

Kani, Yuko; Kamosida, Mamoru; Watanabe, Daisuke; Asano, Takashi; Tamata, Shin

2013-01-01

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 the 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 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 d s with different dependency on the brine concentration were observed based on the mechanism of cesium adsorption. As for strontium, K 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 d s and it was used for

Removal and recovery of radionuclides and toxic metals from wastes, soils and materials

International Nuclear Information System (INIS)

Francis, A.J.

1993-07-01

A process has been developed at Brookhaven National Laboratory (BNL) for the removal of metals and radionuclides from contaminated materials, soils, and waste sites (Figure 1). In this process, citric acid, a naturally occurring organic complexing agent, is used to extract metals such as Ba, Cd, Cr, Ni, Zn, and radionuclides Co, Sr, Th, and U from solid wastes by formation of water soluble, metal-citrate complexes. Citric acid forms different types of complexes with the transition metals and actinides, and may involve formation of a bidentate, tridentate, binuclear, or polynuclear complex species. The extract containing radionuclide/metal complex is then subjected to microbiological degradation followed by photochemical degradation under aerobic conditions. Several metal citrate complexes are biodegraded and the metals are recovered in a concentrated form with the bacterial biomass. Uranium forms binuclear complex with citric acid and is not biodegraded. The supernatant containing uranium citrate complex is separated and upon exposure to light, undergoes rapid degradation resulting in the formation of an insoluble, stable polymeric form of uranium. Uranium is recovered as a precipitate (uranium trioxide) in a concentrated form for recycling or for appropriate disposal. This treatment process, unlike others which use caustic reagents, does not create additional hazardous wastes for disposal and causes little damage to soil which can then be returned to normal use

Removal of radionuclides from partitioning waste solutions by adsorption and catalytic oxidation methods

Energy Technology Data Exchange (ETDEWEB)

Yamagishi, Isao; Yamaguchi, Isoo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kubota, Masumitsu [Research Organization for Information Science and Technology (RIST), Tokai, Ibaraki (Japan)

2000-09-01

Adsorption of radionuclides with inorganic ion exchangers and catalytic oxidation of a complexant were studied for the decontamination of waste solutions generated in past partitioning tests with high-level liquid waste. Granulated ferrocyanide and titanic acid were used for adsorption of Cs and Sr, respectively, from an alkaline solution resulting from direct neutralization of an acidic waste solution. Both Na and Ba inhibited adsorption of Sr but Na did not that of Cs. These exchangers adsorbed Cs and Sr at low concentration with distribution coefficients of more than 10{sup 4}ml/g from 2M Na solution of pH11. Overall decontamination factors (DFs) of Cs and total {beta} nuclides exceeded 10{sup 5} and 10{sup 3}, respectively, at the neutralization-adsorption step of actual waste solutions free from a complexant. The DF of total {alpha} nuclides was less than 10{sup 3} for a waste solution containing diethylenetriaminepentaacetic acid (DTPA). DTPA was rapidly oxidized by nitric acid in the presence of a platinum catalyst, and radionuclides were removed as precipitates by neutralization of the resultant solution. The DF of {alpha} nuclides increased to 8x10{sup 4} by addition of the oxidation step. The DFs of Sb and Co were quite low through the adsorption step. A synthesized Ti-base exchanger (PTC) could remove Sb with the DF of more than 4x10{sup 3}. (author)

Investigations of white light emitting europium doped zinc oxide nanoparticles

International Nuclear Information System (INIS)

Ashtaputre, S S; Nojima, A; Marathe, S K; Matsumura, D; Ohta, T; Tiwari, R; Dey, G K; Kulkarni, S K

2008-01-01

Europium doped zinc oxide nanoparticles have been synthesized using a chemical route. The amount of doped europium was varied which shows the changes in the photoluminescence (PL) intensity. The post synthesis annealing effect on the properties of ZnO nanoparticles has also been investigated. In general, PL is broad and a white light is emitted which originates from ZnO and the intra-4f transitions of Eu 3+ ions. The x-ray diffraction patterns do not show any Eu-related peaks for as-synthesized ZnO nanoparticles as well as for annealed samples. X-ray absorption spectroscopy reveals that europium ions are present on the surface of the core of ZnO and inside the shell of zinc hydroxide [Zn(OH 2 )] after annealing

Development of ultraviolet LED devices containing europium (III) complexes in fluorescence layer

International Nuclear Information System (INIS)

Iwanaga, Hiroki; Amano, Akio; Aiga, Fumihiko; Harada, Kohichi; Oguchi, Masayuki

2006-01-01

Relations between molecular structures of europium complexes and their luminescent properties were investigated. Europium complex with β-diketones and two different phosphine oxides 8 was highly soluble in fluorinated medium, and realized largest fluorescence intensities. The luminous intensity of ultraviolet light emitting diodes devices (LEDs) whose fluorescence layer consists of fluorinated polymer and 8 was over 200 mcd (20 mA). Fluorescence compounds of this type are promising for application in next-generation white LEDs. Moreover, we proposed a novel molecular design of europium complex with asymmetric diphosphine dioxide

Sorption of small amounts of europium(III) on iron(III) hydroxide and oxide

International Nuclear Information System (INIS)

Music, S.; Gessner, M.; Wolf, R.H.H.

1979-01-01

The sorption of small amounts of europium(III) on iron(III) hydroxide and oxide has been studied as a function of pH. The mechanism of sorption is discussed. Optimum conditions have been found for the preconcentration of small or trace amounts of europium(III) by iron(III) hydroxide and oxide. The influence of complexing agents (EDTA, oxalate, tartrate and 5-sulfosalicylic acid) on the sorption of small amounts of europium(III) on iron(III) oxide has also been studied. (author)

Characterisation of kaolinite and adsorption of europium on kaolinite

International Nuclear Information System (INIS)

Olin, M.; Puhakka, E.; Lehikoinen, J.; Puukko, E.; Hakanen, M.; Lindberg, A.

2007-10-01

Kaolinite is a common fracture mineral in many crystalline rocks and, thus, a potential sorbent for groundwater solutes. The low cation-exchange capacity makes kaolinite a good mineral to study sorption by inner-sphere complexation of multivalent ions, such as trivalent actinides or their analogues, the trivalent lanthanides. The sorption of europium and americium on kaolinite has been studied previously by Puukko and Hakanen using a natural kaolinite, KGa-1b (from the Clay Minerals Society, USA). This work describes the determination of surface-charging mechanism and surface acidity constants for KGa-1b kaolinite, and adsorption of Eu(III) on both the natural (KGa-1b) and its acid-conditioned form (HKGa). The ionic strength of the background NaNO 3 electrolyte used in these titrations was 0.05 M, 0.1 M and 0.5 M. The surface acidity of kaolinite was explained using the FITEQL software by applying the 1-pK model. The optimized concentration of surface sites was close to a value previously reported for KGa-1b kaolinite. The adsorption modelling of europium was carried out by adopting one surfacecomplexation and one cation-exchange reaction. In the acidic pH range, sorption of europium decreased with increasing ionic strength of the NaNO 3 solution, which is an indication of the dominance of cation exchange or outer-sphere complexation. At the lowest ionic strength, the sorption was reversible. In the 0.1 M and 0.5 M NaNO 3 solutions, the sorption of europium in the basic pH range was only partly reversible, or desorption kinetically slow. The degree of irreversibility increased with increasing pH and ionic strength. A diffuse-layer model was readily fitted on the per-cents sorbed scale (default in FITEQL), but the results were not as good on a Kd scale, especially at circumneutral pH values. In the water analysis of the batch titration of KGa-1b kaolinite, the main observed elements were aluminium and zinc. The concentrations of Al and Zn decreased with p

Magnetic and structural properties of yellow europium oxide compound and Eu(OH)3

International Nuclear Information System (INIS)

Lee, Dongwook; Seo, Jiwon; Valladares, Luis de los Santos; Avalos Quispe, O.; Barnes, Crispin H.W.

2015-01-01

A new material based on a yellow europium oxide compound was prepared from europium oxide in a high vacuum environment. The structural and magnetic properties of the material were investigated. Owing to the absence of a crystal structure, the material exhibited a disordered magnetic behavior. In a reaction with deionized (DI) water without applied heat, the compound assumed a white color as soon as the DI water reached the powder, and the structure became polycrystalline Eu(OH) 3 . The magnetic properties, such as the thermal hysteresis, disappeared after the reaction with DI water, and the magnetic susceptibility of the yellow oxide compound weakened. The magnetic properties of Eu(OH) 3 were also examined. Although Eu 3+ is present in Eu(OH) 3 , a high magnetic moment due to the crystal field effect was observed. - Graphical abstract: (top left) Optical image of the yellow europium oxide compound. (top right) Optical image of the product of DI water and yellow europium oxide. (bottom) Magnetization curves as a function of temperature measured in various magnetic field. - Highlights: • We prepared a new material based on a yellow europium oxide compound from europium oxide. • We characterized the magnetic properties of the material which exhibits a disordered magnetic behavior such as thermal hysteresis. • The compound turned white (Eu(OH) 3 ) as soon as the DI water reached the powder. • The thermal hysteresis disappeared after the reaction with DI water and the magnetic susceptibility of the yellow oxide compound weakened

Removal of radionuclides from household water; Metoder foer avlaegsnande av radionuklider fraan hushaallsvatten

Energy Technology Data Exchange (ETDEWEB)

Vesterbacka, P.; Turtiainen, T.; Haemaelaeinen, K.; Salonen, L.; Arvela, H.

2007-02-15

Research upon methods for removing radionuclides from household water was initiated in Finland in 1995. Three research projects, of which two were carried out with National Technology Agency of Finland and one with CEC, have been completed by the end of 2002. One of the main objectives of the research was to compose a guidebook for consumers and water treatment companies. Radon can be removed from household water by aeration and by activated carbon filtration. Aerators that are well designed and set up can remove over 90% of waterborne radon. The best aerators have achieved removal efficiencies that are nearly 100%. However, setting up an aeration system requires thorough planning. Also, activated carbon filtration removes radon efficiently. The removal efficiencies have been over 90%, often nearly 100%. Depending on the water quality and usage, the carbon batch inside the filter needs to be changed every 2 - 3 years. Since activated carbon filters emit gamma radiation while in use, they should not be installed inside the dwelling but in a separate building or by the well. It is recommended that uranium be removed from drinking water by anion exchange, which is the most efficient removal method for this purpose. Typically, the removal efficiencies are nearly 100%. The one exception is the so called tap filter, the removal efficiency of which depends on uranium concentration in raw water and the rate of water flow. High saline concentration in water may extricate uranium from ion exchange resin. Changes in plumbing pressure or pH-value do not have any significant influence in uranium retention. Removal efficiencies of lead and polonium vary a lot depending on the chemical form in which they occur in water. They can be reliably removed from water by reverse osmosis only. Other treatment methods, such as ion exchange and activated carbon filtration, remove lead and polonium partly. Lead and polonium are removed more efficiently when they are bound onto smaller

Improvements in lung lavage to increase its effectiveness in removing inhaled radionuclides

International Nuclear Information System (INIS)

Muggenburg, B.A.; Guilmette, R.A.; Romero, L.M.; Mewhinney, J.A.

1991-01-01

Lung lavage has been shown to be an effective method to remove insoluble radionuclides deposited and retained in the lung, but the treatment has been limited to the effective removal of only about 50% of the retained material. Reported here is change in lavage technique that slightly increases the effectiveness and the addition of high-frequency chest wall oscillation. The latter increased the effectiveness of the lavage procedure but also caused significant physiological complications. These studies were conducted in adult male and female beagles. The aerosol in the first study was 239 PuO 2 heat-treated at 850 degrees C, obtained as powder from a commercial V-blending process. The dogs briefly inhaled the aerosol per nasi. The tissue content at death and the amount of 239 Pu excreted and in the recovered lung lavage fluid was determined by radiochemical methods 5 . These values were used to reconstruct the initial pulmonary burden of 239 and the amount of 239 Pu removed by lavage. In the second study, with the HFCWO, the aerosol was 85 Sr fused in aluminosilicate particles. The IPB of 85 Sr was determined by whole-body counting. The excreta and recovered lung lavage fluids were also assayed for 85 Sr activity

Synthesis and luminescence properties for europium oxide nanotubes

International Nuclear Information System (INIS)

Mo Zunli; Deng Zhepeng; Guo Ruibin; Fu Qiangang; Feng Chao; Liu Pengwei; Sun Yu

2012-01-01

Highlights: ► A novel high temperature sensitive fluorescent CNTs/Eu 2 O 3 nanocomposite was fabricated. ► The nanocomposite showed strong fluorescent emission peaks at around 540 and 580 nm after calcined beyond 620 °C for 4 h. ► The ultrahigh fluorescence intensity of the nanocomposites resulted from a synergetic effect of CNTs and europium oxide. ► We also discovered that CNTs had an effect of fluorescence quenching. - Abstract: A novel high temperature sensitive fluorescent nanocomposite has been successfully synthesized by an economic hydrothermal method using carbon nanotubes (CNTs), europium oxide, and sodium dodecyl benzene sulfonate (SDBS). To our great interest, the nanocomposites show high temperature sensitivity after calcinations at various temperatures, suggesting a synergetic effect of CNTs and europium oxide which leads to ultrahigh fluorescence intensity of europium oxide nanotubes. When the novel high temperature sensitive fluorescent nanocomposites were calcined beyond 620 °C for 4 h, the obtained nanocomposites have a strong emission peak at around 540 and 580 nm, due to the 5 D 0 → 7 F j (j = 0, 1) forced electric dipole transition of Eu 3+ ions. In turn, the emission spectra showed a slight blue shift. The intensity of this photoluminescence (PL) band is remarkably temperature-dependent and promotes strongly beyond 620 °C. This novel feature is attributed to the thermally activated carrier transfer process from nanocrystals and charged intrinsic defects states to Eu 3+ energy levels. The novel high temperature sensitive fluorescent nanocomposite has potential applications in high temperature warning materials, sensors and field emission displays. It is also interesting to discover that CNTs have the effect of fluorescence quenching.

Luminescent properties of europium different-ligand complexes with cyclic. beta. -diketones and diantipyrylalkanes

Energy Technology Data Exchange (ETDEWEB)

Ul' yanova, T M; Gerasimenko, G N; Tishchenko, M A; Vitkun, R A [AN Ukrainskoj SSR, Odessa. Fiziko-Khimicheskij Inst.

1983-03-01

Using luminescence method different-ligand complexing of europium ions with diantipyrylalkanes and cyclic ..beta..-diketones: 2-acetyl- and 2-benzoyl-1.3-indandions, has been studied. The optimum conditions of the formation of different-ligand complexes and the ratio of components in it are determined. Effect of alien lanthanides and diantipyrylmethane derivatives on the luminescence intensity of europium complexes is clarified. A correlation between the ratio of the luminescence intensity bands of europium complexes and the values of oscillator strengths of supersensitive transitions of neodymium and erbium absorption bands is established.

Composite materials based on inorganic sorbents and extractants - new sorbents for several radionuclides removal from liquid radioactive wastes

International Nuclear Information System (INIS)

Kopyrin, A.A.

1999-01-01

A short review of recent investigation concerned with liquid radioactive waste treatment by means of composite materials. It is considered different aspects of technology of selective radionuclides removal and its direction connected with usage of composites. Results of research works in this line carried out under the direction of author are presented. (author)

Extraction of europium (3) ions with stearic acid

International Nuclear Information System (INIS)

Lobanov, F.I.; Gladyshchev, V.P.; Nurtaeva, A.K.; Andreeva, N.N.

1981-01-01

Extraction of europium (3) in nitric acid solutions with the melts of stearic acid and its mixtures with paraffin at (80+-1) deg C is studied. The constant of stearic acid dimerization in paraffin K 2 =9.6+-0.6 and the constant of stearic acid distribution in the paraffin-water system Ksub(D,HA)=(1.06+-0.07)x10sub(3) are determined. The diagram of europium ion extraction at initial concentrations of metal in the aqueous phase of 10 -4 -10 -3 mol/l is suggested. The compound extracted has the EuA 3 composition with extraction constant of lg Ksub(ex)=-7.58 [ru

Generator for radionuclide

International Nuclear Information System (INIS)

Weisner, P.S.; Forrest, T.R.F.

1985-01-01

This invention provides a radionuclide generator of the kind in which a parent radionuclide, adsorbed on a column of particulate material, generates a daughter radionuclide which is periodically removed from the column. This invention is particularly concerned with technetium generators using single collection vials. The generator comprises a column, a first reservoir for the eluent, a second reservoir to contain the volume of eluent required for a single elution, and means connecting the first reservoir to the second reservoir and the second reservoir to the column. Such a generator is particularly suitable for operation by vacuum elution

Synthesis and spectroscopic behavior of highly luminescent trinuclear europium complexes with tris-β-diketone ligand

Energy Technology Data Exchange (ETDEWEB)

Wang, Dunjia, E-mail: dunjiawang@163.com; Pi, Yan; Liu, Hua; Wei, Xianhong; Hu, Yanjun; Zheng, Jing

2014-11-15

Highlights: • Synthesis of the tris-β-diketone ligand and its trinuclear europium complexes. • Photoluminescence behavior of trinuclear europium complexes. • Analysis of the Judd–Ofelt intensity parameters (Ω{sub t}), lifetime (τ) and quantum yield (η). - Abstract: A new tris-β-diketone ligand, 2-[4,6-bis-(1-benzoyl-2-oxo-2-phenyl-ethyl)-[1,3,5]triazin-2-yl] -1,3-diphenyl-propane-1,3-dione (H{sub 3}L), and its trinuclear europium complexes, Eu{sub 3}(DBM){sub 6}L (C1), Eu{sub 3}(DBM){sub 6}(Bipy){sub 3}L (C2) and Eu{sub 3}(DBM){sub 6}(Phen){sub 3}L (C3) were synthesized and their spectroscopic behaviors were studied by FT-IR, {sup 1}H NMR, UV–vis and photoluminescence spectroscopic techniques. These europium complexes exhibited the characteristic emission bands that arise from the {sup 5}D{sub 0} → {sup 7}F{sub J} (J = 0–4) transitions of the europium ion in solid state. The Ω{sub 2} and Ω{sub 4} intensity parameters, lifetime (τ) and luminescence quantum yield (η) were calculated according to the emission spectra and luminescence decay curves in solid state. The results indicated that these trinuclear europium complexes displayed a longer lifetime (τ) and higher luminescence quantum efficiency (η), especially complexes C2 (τ = 0.820 ms, η = 46.5%) and C3 (τ = 0.804 ms, η = 47.4%), which due to the effect of two additional europium ion lumophors and the introduction of the third ligands, Bipy or Phen in trinuclear complexes. Their Ω{sub 2} values demonstrated that the europium ion in these complexes is in a highly polarizable chemical environment.

Spectroscopic studies of europium-tetracyclines complexes and their applications in detection of hydrogen peroxide and urea peroxide

International Nuclear Information System (INIS)

Grasso, Andrea Nastri

2010-01-01

In this work were studied the spectroscopic properties of trivalent europium ion complexed with components of tetracycline family, chlorotetracycline, oxytetracycline and metacycline, in the presence of hydrogen peroxide and urea peroxide. Optical parameters were obtained such as absorption, emission, lifetime and calibration curves were constructed for luminescence spectra. Experiments were carried out with both inorganic compounds and europium-tetracyclines complexes in order to verify possible interferences. Studies for glucose determination were also described using europium-tetracyclines complexes as biosensors. Results show that europium tetracyclines complexes emit a narrow band in the visible region and, in the presence of hydrogen peroxide or urea peroxide there is a greater enhancement in their luminescence and lifetime. Thus, europium-tetracyclines complexes studied can be used as biosensors for hydrogen and urea peroxides determination as a low cost and room temperature method. An indirect method for glucose determination was studied by adding glucose oxidase enzyme in europium-tetracyclines complex in the presence of glucose promoting as product hydrogen peroxide. (author)

On the composition of nonstoichiometric europium monoxide

International Nuclear Information System (INIS)

Ignat'eva, N.I.

1990-01-01

Consideration is given to results of of investigation into chemical composition, homogeneity region, type of disordering of nonstoichiometric europium monoxide. Precision methods of X-ray diffraction, electron-microscopic, atomic-absorption chemical analysis were used. It is shown that lattice volume reduces with increase of oxygen content in the oxide. For monocrystal of EuO 1.01 composition a=5.146 A. All samples of europium monoxide are characterized by low conductivity. Conductivity value changes by two orders (from 10 -8 to 10 -6 Θ -1 ·cm -1 ) when passing from the sample of stoichiometric composition to maximally disordered one. The disordering is considered according to the type of charged cation vacancies, leading to occurrence of equivalent number of electron defects of positive holes. 4 refs.; 1 tab

Formation of americium and europium humate complexes

International Nuclear Information System (INIS)

Minai, Y.; Tominaga, T.; Meguro, Y.

1991-01-01

Binding constants of americium and europium with a humic acid were determined to study if complex formation of trivalent actinide-humates affects dissolved species of the actinides in hydrosphere. The purified humic acid was characterized by means of UV-vis, IR, and pH titration, indicating high carboxylate capacity and low aromaticity. Binding constants of americium and europium humates were determined at pH 4.6 and 6.0 by solvent extraction using 241 Am or 152 Eu as a tracer. The binding constants for americium-humate obtained preliminarily suggest that complexes with humic acid are not negligible in speciation of trivalent actinides in hydrosphere. The obtained binding constants were nearly identical with those determined previously by the same procedures, but with humic acids of different origin and compositions. (author)

Sorption of europium (3) by polymer sorbents with grafted heterocyclic nitrogen-containing groupings

International Nuclear Information System (INIS)

Bel'tyukova, S.V.; Kravchenko, T.B.; Balamtsarashvili, G.M.; Roska, A.S.

1990-01-01

On polymer sorbents (copolymer of styrene-divinylbenzene) with grafted heterocyclic nitrogen-containing functional groupings of tetrazole, triazole and imidazole (sorbents 1,2,3, respectively). It is stated that europium sorption takes place from neutral solutions in presence of organic solvents. Luminescent properties of europium on sorbent are used to develope methods of its determination in high purity lanthanide and yttrium oxides. Europium determination limits consist 7.5·10 -5 μg/ml on 1 and 3 sorbents and 1.5·10 -4 μg/ml on sorbent 2, S p value is 0.089 and 0.075, respectivaly

Regulatory Technology Development Plan - Sodium Fast Reactor. Mechanistic Source Term - Metal Fuel Radionuclide Release

International Nuclear Information System (INIS)

Grabaskas, David; Bucknor, Matthew; Jerden, James

2016-01-01

The development of an accurate and defensible mechanistic source term will be vital for the future licensing efforts of metal fuel, pool-type sodium fast reactors. To assist in the creation of a comprehensive mechanistic source term, the current effort sought to estimate the release fraction of radionuclides from metal fuel pins to the primary sodium coolant during fuel pin failures at a variety of temperature conditions. These release estimates were based on the findings of an extensive literature search, which reviewed past experimentation and reactor fuel damage accidents. Data sources for each radionuclide of interest were reviewed to establish release fractions, along with possible release dependencies, and the corresponding uncertainty levels. Although the current knowledge base is substantial, and radionuclide release fractions were established for the elements deemed important for the determination of offsite consequences following a reactor accident, gaps were found pertaining to several radionuclides. First, there is uncertainty regarding the transport behavior of several radionuclides (iodine, barium, strontium, tellurium, and europium) during metal fuel irradiation to high burnup levels. The migration of these radionuclides within the fuel matrix and bond sodium region can greatly affect their release during pin failure incidents. Post-irradiation examination of existing high burnup metal fuel can likely resolve this knowledge gap. Second, data regarding the radionuclide release from molten high burnup metal fuel in sodium is sparse, which makes the assessment of radionuclide release from fuel melting accidents at high fuel burnup levels difficult. This gap could be addressed through fuel melting experimentation with samples from the existing high burnup metal fuel inventory.

Regulatory Technology Development Plan - Sodium Fast Reactor. Mechanistic Source Term - Metal Fuel Radionuclide Release

Energy Technology Data Exchange (ETDEWEB)

Grabaskas, David [Argonne National Lab. (ANL), Argonne, IL (United States); Bucknor, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States); Jerden, James [Argonne National Lab. (ANL), Argonne, IL (United States)

2016-02-01

The development of an accurate and defensible mechanistic source term will be vital for the future licensing efforts of metal fuel, pool-type sodium fast reactors. To assist in the creation of a comprehensive mechanistic source term, the current effort sought to estimate the release fraction of radionuclides from metal fuel pins to the primary sodium coolant during fuel pin failures at a variety of temperature conditions. These release estimates were based on the findings of an extensive literature search, which reviewed past experimentation and reactor fuel damage accidents. Data sources for each radionuclide of interest were reviewed to establish release fractions, along with possible release dependencies, and the corresponding uncertainty levels. Although the current knowledge base is substantial, and radionuclide release fractions were established for the elements deemed important for the determination of offsite consequences following a reactor accident, gaps were found pertaining to several radionuclides. First, there is uncertainty regarding the transport behavior of several radionuclides (iodine, barium, strontium, tellurium, and europium) during metal fuel irradiation to high burnup levels. The migration of these radionuclides within the fuel matrix and bond sodium region can greatly affect their release during pin failure incidents. Post-irradiation examination of existing high burnup metal fuel can likely resolve this knowledge gap. Second, data regarding the radionuclide release from molten high burnup metal fuel in sodium is sparse, which makes the assessment of radionuclide release from fuel melting accidents at high fuel burnup levels difficult. This gap could be addressed through fuel melting experimentation with samples from the existing high burnup metal fuel inventory.

Atomic absorption spectrophotometry of europium using an enhancing effect of ammonium perchlorate

International Nuclear Information System (INIS)

Oguro, Hiroshi

1976-01-01

In the atomic absorption spectrophotometry of europium in air-acetylene flame, ammonium perchlorate (NH 4 ClO 4 ) increases the absorption of europium. In the case of 0.5 M NH 4 ClO 4 , the increase is by about 1.5 times. In this paper, a method for eliminating the interferences of many coexisting compounds using an enhancing effect and a method for determining Eu 2 O 3 in La 2 O 3 were investigated. The working conditions using Nippon Jarrell-Ash model AA-1 atomic absorption/flame emission spectrophotometer were as follows; wavelength 4594 A, lamp current 15 mA, burner height 10 mm, air flow-rate 6.51/min, acetylene flow-rate 1.81/min. Though the enhancing or depressing effects of HCl, HNO 3 , HBr and HClO 4 in concentrations below 0.1 M were eliminated by 0.5 M NH 4 ClO 4 , the remarkable depressing effects of H 2 SO 4 and H 3 PO 4 on europium could not be eliminated. The interferences of Na + , K + , Cs + and Al 3+ in the concentration of 200 ppm were not eliminated, but those of other cations including rare earth elements were completely eliminated. Lanthanum in the range of (2000--10000) ppm increased the absorption of europium by about 1.4 times. But the effect of lanthanum in the range of (0--9000) ppm was also eliminated by NH 4 ClO 4 . The calibration curve for europium in the presence of NH 4 ClO 4 was linear in the range of (0--400) ppm with a sensitivity larger by about 1.5 times than that for europium alone. The analytical procedure is as follows. A sample is dissolved in HCl and NH 4 ClO 4 is added. Europium in the sample solution is determined by atomic absorption method using air-acetylene flame. For practical samples, the values obtained were in fair agreement with those by the flame emission method using a nitrous oxide-acetylene flame. The coefficients of variation by the present method were (3.7--2.4)% (Eu 2 O 3 content (1--3)%). (auth.)

Assessment of the radionuclide composition of "hot particles" sampled in the Chernobyl nuclear power plant fourth reactor unit.

Science.gov (United States)

Bondarkov, Mikhail D; Zheltonozhsky, Viktor A; Zheltonozhskaya, Maryna V; Kulich, Nadezhda V; Maksimenko, Andrey M; Farfán, Eduardo B; Jannik, G Timothy; Marra, James C

2011-10-01

Fuel-containing materials sampled from within the Chernobyl Nuclear Power Plant (ChNPP) Unit 4 Confinement Shelter were spectroscopically studied for gamma and alpha content. Isotopic ratios for cesium, europium, plutonium, americium, and curium were identified, and the fuel burn-up in these samples was determined. A systematic deviation in the burn-up values based on the cesium isotopes in comparison with other radionuclides was observed. The studies conducted were the first ever performed to demonstrate the presence of significant quantities of 242Cm and 243Cm. It was determined that there was a systematic underestimation of activities of transuranic radionuclides in fuel samples from inside of the ChNPP Confinement Shelter, starting from 241Am (and going higher) in comparison with the theoretical calculations.

Use of synthetic zeolites and other inorganic sorbents for the removal of radionuclides from aqueous wastes

International Nuclear Information System (INIS)

Samantha, S.K.; Singh, I.J.; Jain, S.; Sathi, S.; Venkatesan, K.; Ramaswamy, M.; Theyyunni, T.K.; Siddiqui, H.R.

1997-01-01

Several synthetic zeolites and inorganic sorbents were tested in the laboratory for the sorption of various radionuclides present in radioactive aqueous waste streams originating from nuclear installations. The sorption of the critical radionuclides like 137 Cs, 90 Sr and 60 Co from level waste solutions was studied using the synthetic zeolites 4A, 13X and AR1 of Indian origin. Granulated forms of ammonium molybdophosphate and CaSO 4 -BaSO 4 eutectoid were tested for the sorption of cesium and strontium respectively, from acidic solutions. The removal of radiostrontium from alkaline salt-loaded intermediate level reprocessing wastes was studied using hydrous ferric oxide-activated carbon composite sorbent, hydrous titania and hydrous manganese dioxide.. The results of these investigations are expected to be of value in formulating radioactive waste treatment schemes for achieving high decontamination and volume reduction factors. (author). 12 refs, 5 figs, 18 tabs

Thermodynamic and structural description of europium complexation in 1-octanol - H2O solutions

International Nuclear Information System (INIS)

Vu, T.H.; Charbonnel, M.C.; Boubals, N.; Couston, L.; Arnaud, F.

2008-01-01

Polydentate N-bearing ligands such as bis-triazinyl-pyridines (BTPs) are interesting extractants for actinide(III)/lanthanide(III) separation. A description of europium complexation in 1-octanol solutions was undertaken to enhance the knowledge of the extraction mechanisms. The first solvation shell for europium(III) nitrate, chloride, and perchlorate with different amounts of water was determined by Time-Resolved Laser-Induced Fluorescence (TRLIF) spectroscopy. Europium nitrate complexation by iPr-BTP was then studied by TRLIF and micro-calorimetry; similar stability constants related to the formation of Eu(BTP) 2 3+ and Eu(BTP) 3 3+ were obtained by both techniques (log(β 2 ) = 9.0 ± 0.3 and log(β 3 ) = 13.8 ± 0.2). The presence of water in the octanol diluent has an influence on solvation of europium and also on the [Eu(BTP) 2 3+ ] / [Eu(BTP) 3 3+ ] ratio. (authors)

Optical and magnetization studies on europium based iron pnictides

International Nuclear Information System (INIS)

Zapf, Sina Maria Ute

2015-01-01

The investigations carried out in the framework of this thesis mainly concentrate on europium based iron pnictides. These are a peculiar member of the 122 family as they develop at low temperatures (∝20K) an additional magnetic order of the local rare earth moments. Therefore, europium based iron pnictides provide a unique platform to study the interplay of structural, magnetic and electronic effects in high-temperature superconductors. For this challenging purpose, we have employed SQUID magnetometry and Fourier-transform infrared spectroscopy on EuFe 2 (As 1-x P x ) 2 single crystals. By systematic studies of the in- and out-of-plane magnetic properties of a series of single crystals, we derived the complex magnetic phase diagram of europium based iron pnictides, which contains an A-type antiferromagnetic and a re-entrant spin glass phase. Furthermore, we have investigated the magneto-optical properties of EuFe 2 As 2 , revealing a much more complex magnetic detwinning process than expected. These studies demonstrate a remarkable interdependence between magnetic, electronic and structural effects that might be very important to understand the unconventional superconductivity in these fascinating materials.

Optical and magnetization studies on europium based iron pnictides

Energy Technology Data Exchange (ETDEWEB)

Zapf, Sina Maria Ute

2015-07-01

The investigations carried out in the framework of this thesis mainly concentrate on europium based iron pnictides. These are a peculiar member of the 122 family as they develop at low temperatures (∝20K) an additional magnetic order of the local rare earth moments. Therefore, europium based iron pnictides provide a unique platform to study the interplay of structural, magnetic and electronic effects in high-temperature superconductors. For this challenging purpose, we have employed SQUID magnetometry and Fourier-transform infrared spectroscopy on EuFe{sub 2}(As{sub 1-x}P{sub x}){sub 2} single crystals. By systematic studies of the in- and out-of-plane magnetic properties of a series of single crystals, we derived the complex magnetic phase diagram of europium based iron pnictides, which contains an A-type antiferromagnetic and a re-entrant spin glass phase. Furthermore, we have investigated the magneto-optical properties of EuFe{sub 2}As{sub 2}, revealing a much more complex magnetic detwinning process than expected. These studies demonstrate a remarkable interdependence between magnetic, electronic and structural effects that might be very important to understand the unconventional superconductivity in these fascinating materials.

Magnetic and structural properties of yellow europium oxide compound and Eu(OH){sub 3}

Energy Technology Data Exchange (ETDEWEB)

Lee, Dongwook, E-mail: dongwookleedl324@gmail.com [Cavendish Laboratory, University of Cambridge, J. J Thomson Av., Cambridge CB3 0HE (United Kingdom); Seo, Jiwon, E-mail: jiwonseo@yonsei.ac.kr [Department of Physics and IPAP, Yonsei University, Seoul 120-749 (Korea, Republic of); Valladares, Luis de los Santos [Cavendish Laboratory, University of Cambridge, J. J Thomson Av., Cambridge CB3 0HE (United Kingdom); Avalos Quispe, O. [Laboratorio de Cerámicos y Nanomateriales, Facultad de Ciencias Físicas, Universidad Nacional Mayor de San Marcos, Ap. Postal 14-0149, Lima, Perú (Peru); Barnes, Crispin H.W. [Cavendish Laboratory, University of Cambridge, J. J Thomson Av., Cambridge CB3 0HE (United Kingdom)

2015-08-15

A new material based on a yellow europium oxide compound was prepared from europium oxide in a high vacuum environment. The structural and magnetic properties of the material were investigated. Owing to the absence of a crystal structure, the material exhibited a disordered magnetic behavior. In a reaction with deionized (DI) water without applied heat, the compound assumed a white color as soon as the DI water reached the powder, and the structure became polycrystalline Eu(OH){sub 3}. The magnetic properties, such as the thermal hysteresis, disappeared after the reaction with DI water, and the magnetic susceptibility of the yellow oxide compound weakened. The magnetic properties of Eu(OH){sub 3} were also examined. Although Eu{sup 3+} is present in Eu(OH){sub 3}, a high magnetic moment due to the crystal field effect was observed. - Graphical abstract: (top left) Optical image of the yellow europium oxide compound. (top right) Optical image of the product of DI water and yellow europium oxide. (bottom) Magnetization curves as a function of temperature measured in various magnetic field. - Highlights: • We prepared a new material based on a yellow europium oxide compound from europium oxide. • We characterized the magnetic properties of the material which exhibits a disordered magnetic behavior such as thermal hysteresis. • The compound turned white (Eu(OH){sub 3}) as soon as the DI water reached the powder. • The thermal hysteresis disappeared after the reaction with DI water and the magnetic susceptibility of the yellow oxide compound weakened.

Evaluation and testing of HUMASORB-CS trademark for the removal of radionuclides from groundwater

International Nuclear Information System (INIS)

Mann, N.R.; Todd, T.A.; Wood, D.J.

1998-01-01

An independent experiment to demonstrate the combined removal of the radionuclides, 85 Sr and 137 Cs from groundwater has been conducted with the sorbent, HUMASORB-CS. Arctech, Inc. manufactures this humic acid-based sorbent material. This sorbent material is reported to have potential for remediation of contaminated groundwater present at DOE sites. The purpose of this work was to evaluate the removal efficiency and the capacity of the sorbent. Two ion-exchange columns were assembled at the Idaho Chemical Processing Plant (ICPP) to evaluate the sorbent technology. Initial 137 Cs breakthrough in both columns was observed after 22.0 and 30.2 bed volumes, respectively. Strontium-85 removal was slightly more efficient than 137 Cs removal. Initial 85 Sr breakthrough in both columns was observed after 29.4 and 22.7 bed volumes, respectively. Calcium, which is of concern, is the major constituent within the feed solution. Calcium is attributed to loading interference in addition to other alkaline and alkaline earth metals such as stable Sr, Mg, Na, K, and Ba. Interfering ions fill exchange sites that greatly reduce the sorbents efficiency to sorb targeted ions such as radioactive Cs and Sr. Despite high concentrations of Ca in the feed solution, Ca was not sorbed by HUMASORB-CS. Results indicate HUMASORB-CS does not sorb sodium or potassium. Sodium and potassium concentrations were consistently observed at 100% breakthrough throughout the test

Study of the effect of the fibre mass UP2 degradation products on radionuclide mobilisation

Energy Technology Data Exchange (ETDEWEB)

Duro, Lara; Grive, Mireia; Gaona, Xavier; Bruno, Jordi [Amphos 21 Consulting S.L., Barcelona (Spain); Andersson, Thomas; Boren, Hans; Dario, Maarten [Linkoeping Univ., Linkoeping (Sweden); Allard, Bert; Hagberg, Jessica [Oerebro Univ., Oerebro (Sweden); Kaellstroem, Klas [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

2012-09-15

This report presents a literature review and laboratory work of the degradation of the fibre UP2, as well as an assessment of the effects of its degradation products on Europium sorption onto cement, as an example of their effects on radionuclide migration. All laboratory work was performed by the Swedish groups (Linkoeping and Oerebro Universities), who also performed some of the literature review. The data interpretation was performed by the Spanish team (Amphos 21). SKB has combined the reports of these studies into this common document and has added minor editorial changes. All these changes have been accepted by the authors.

Study of the effect of the fibre mass UP2 degradation products on radionuclide mobilisation

International Nuclear Information System (INIS)

Duro, Lara; Grive, Mireia; Gaona, Xavier; Bruno, Jordi; Andersson, Thomas; Boren, Hans; Dario, Maarten; Allard, Bert; Hagberg, Jessica; Kaellstroem, Klas

2012-09-01

This report presents a literature review and laboratory work of the degradation of the fibre UP2, as well as an assessment of the effects of its degradation products on Europium sorption onto cement, as an example of their effects on radionuclide migration. All laboratory work was performed by the Swedish groups (Linkoeping and Oerebro Universities), who also performed some of the literature review. The data interpretation was performed by the Spanish team (Amphos 21). SKB has combined the reports of these studies into this common document and has added minor editorial changes. All these changes have been accepted by the authors

Use of europium ions for SAD phasing of lysozyme at the Cu Kα wavelength

International Nuclear Information System (INIS)

Vijayakumar, Balakrishnan; Velmurugan, Devadasan

2012-01-01

Europium(III) ions bound to the surface of hen egg-white lysozyme were found to exhibit good anomalous signal facilitating SAD phasing using laboratory-source data and automated model building. The europium ion-binding sites were observed up to the 15σ level. Europium is shown to be a good anomalous scatterer in SAD phasing for solving the structure of biological macromolecules. The large value of the anomalous contribution of europium, f′′ = 11.17 e − , at the Cu Kα wavelength is an advantage in de novo phasing and automated model building. Tetragonal crystals of hen egg-white lysozyme (HEWL) incorporating europium(III) chloride (50 mM) were obtained which diffracted to a resolution of 2.3 Å at a wavelength of 1.54 Å (Cu Kα). The master data set (360° frames) was split and analyzed for anomalous signal-to-noise ratio, multiplicity, completeness, SAD phasing and automated building. The structure solution and model building of the split data sets were carried out using phenix.autosol and phenix.autobuild. The contributions of the Eu ions to SAD phasing using in-house data collection are discussed. This study revealed successful lysozyme phasing by SAD using laboratory-source data involving Eu ions, which are mainly coordinated by the side chains of Asn46, Asp52 and Asp101 together with some water molecules

40 CFR 141.66 - Maximum contaminant levels for radionuclides.

Science.gov (United States)

2010-07-01

... beta particle and photon radioactivity from man-made radionuclides in drinking water must not produce.../year). (2) Except for the radionuclides listed in table A, the concentration of man-made radionuclides... may make this technology too complex for small surface water systems. e Removal efficiencies can vary...

Silica- and silylated europium-based luminescent hybrids: new analysis tools for biological environments

International Nuclear Information System (INIS)

Pereira Duarte, Adriana

2012-01-01

The association of the very interesting luminescence properties of the lanthanide chelates with the physicochemical properties of inorganic matrix such as silica is a promising way to obtain new probes or luminescent markers for biology analyses. In this idea, this work focuses on the preparation of new hybrid materials based on the grafting of new europium(III) complexes on silica nanoparticles. These europium complexes were developed in our group using bifunctional ligands containing both complexing and grafting sites. Intrinsic characteristic of the ligands gives us the ability to make a covalent bond between the material surface and the complex. Two different methodologies were used; the first one is the direct grafting reaction involving the complex and silica nanoparticles (i.e. dense or meso-porous particles). The second one is the Stoeber reaction, where the SiO 2 nanoparticles were prepared in presence of the europium complex. The last methodology has an additional difficult, because of the presence of silylated europium complex, it needs a closer control of the physicochemical conditions. The new organic-inorganic hybrid materials, obtained in this work, present an interesting luminescence behavior and this one is depending on the localization of the europium complex, i.e. on the surface or within the nanoparticles. In addition, the obtained hybrids present the nano-metric dimension and the complex is not leachable. Analyses were realized to describe the luminescence properties, beyond surface and structural characteristics. Initial results show that the new hybrids are promising candidates for luminescent bio-markers, particularly for the time-resolved analysis. (author) [fr

Carbamoyl methylphosphine oxide derivatives of adamantane as americium and europium extractants

International Nuclear Information System (INIS)

Babain, V.A.; Alyapyshev, M.Yu.; Novakov, I.A.; Orlinson, B.S.; Savel'ev, E.N.; Shokova, Eh.A.; Serebrayannikova, A.E.; Kovalev, V.V.

2007-01-01

Adamantane di-1,3-carbamoyl methylphosphine oxide (CMPO) derivatives, where CMPO-groups connect with 1,3-positions of rigid adamantane platform by methylene and ethylene bridges, are synthesized, and their efficiency as extractants of americium(III) and europium(III) from nitric acid solutions is demonstrated. Distribution function of Am 3+ and Eu + during extraction from 3M HNO 3 are measured in the investigation of extraction properties. It is noted that first synthesized adamantane CMPO derivatives are more effective for the extraction of americium(III) and europium(III) from 3MHNO 3 [ru

Radionuclide Sensors for Subsurface Water Monitoring. Final report

International Nuclear Information System (INIS)

Timothy DeVol

2006-01-01

Contamination of the subsurface by radionuclides is a persistent and vexing problem for the Department of Energy. These radionuclides must be measured in field studies and monitored in the long term when they cannot be removed. However, no radionuclide sensors existed for groundwater monitoring prior to this team's research under the EMSP program. Detection of a and b decays from radionuclides in water is difficult due to their short ranges in condensed media

Luminescent micro- and nanofibers based on novel europium phthalate complex

Energy Technology Data Exchange (ETDEWEB)

Enculescu, M., E-mail: mdatcu@infim.ro [National Institute of Materials Physics, Multifunctional Materials and Structures, PO Box MG-7, 77125 Magurele-Bucharest (Romania); Preda, N.; Matei, E.; Enculescu, I. [National Institute of Materials Physics, Multifunctional Materials and Structures, PO Box MG-7, 77125 Magurele-Bucharest (Romania)

2012-09-14

We synthesized by wet chemical route a novel europium-potassium phthalate complex Eu{sup 3+}K{sup +}[(COO){sub 2}(C{sub 6}H{sub 4})]{sub 2}. The compound is a white powder insoluble in water. X-ray diffraction evaluation shows that we obtained a new crystalline compound with no traces of the starting materials (potassium hydrogen phthalate and europium chloride). Scanning electron microscopy reveals that the powder consists of fiber-shaped structures with sizes larger than 250 nm in diameter. Energy dispersive X-ray analysis proves that the compound has a 1:1 europium-potassium ratio. Fourier transform infrared spectroscopy confirms the presence of the phthalate in the new compound. Photoluminescence and cathodoluminescence measurements show that the fiber-shaped structures are intensely luminescent with emission bands corresponding to the {sup 5}D{sub 0} {yields} {sup 7}F{sub J} (J = 1-4) Eu (III) ion's transitions in the region between 580 nm and 700 nm, the most intense maximum being observed around 615 nm. Up-converted luminescence with a maximum at 315 nm was recorded. -- Highlights: Black-Right-Pointing-Pointer A new europium-potassium phthalate complex was synthesized by wet chemical route. Black-Right-Pointing-Pointer Fiber-shaped crystalline structures with sizes larger than 250 nm. Black-Right-Pointing-Pointer The most probable structure of the molecule is [C{sub 6}H{sub 4}(COO{sup -}){sub 2}]{sub 2} K{sup +}Eu{sup 3+}. Black-Right-Pointing-Pointer Intense luminescence due to Eu{sup 3+} ions {sup 5}D{sub 0} {yields} {sup 7}F{sub J} transitions. Black-Right-Pointing-Pointer Up-converted luminescence with a maximum at 315 nm was recorded.

Purification and measurement of acid leachable europium in sands as an aid in the study of sediment transport

International Nuclear Information System (INIS)

Ditchburn, R.G.; McCabe, W.J.

1982-05-01

The use of europium labelled sand as an aid in the study of sediment transport has been suggested. A method for the purification of acid leachable europium is described. The final measurement is made by flame emission spectrometry using a nitrous oxide-acetylene flame. The usefulness of the method is limited by the natural levels of europium which, in the sand studied, was around 0.3 ppm

Thermodynamic and structural description of europium complexation in 1-octanol - H{sub 2}O solutions

Energy Technology Data Exchange (ETDEWEB)

Vu, T.H.; Charbonnel, M.C.; Boubals, N.; Couston, L. [CEA Marcoule, DEN/DRCP/SCPS/LCAM, BP 17171, 30207 Bagnols-sur-Ceze (France); Arnaud, F. [Laboratoire de Chimie Physique, IPHC, 25 rue Becquerel, 67087 Strasbourg (France)

2008-07-01

Polydentate N-bearing ligands such as bis-triazinyl-pyridines (BTPs) are interesting extractants for actinide(III)/lanthanide(III) separation. A description of europium complexation in 1-octanol solutions was undertaken to enhance the knowledge of the extraction mechanisms. The first solvation shell for europium(III) nitrate, chloride, and perchlorate with different amounts of water was determined by Time-Resolved Laser-Induced Fluorescence (TRLIF) spectroscopy. Europium nitrate complexation by iPr-BTP was then studied by TRLIF and micro-calorimetry; similar stability constants related to the formation of Eu(BTP){sub 2}{sup 3+} and Eu(BTP){sub 3}{sup 3+} were obtained by both techniques (log({beta}{sub 2}) = 9.0 {+-} 0.3 and log({beta}{sub 3}) = 13.8 {+-} 0.2). The presence of water in the octanol diluent has an influence on solvation of europium and also on the [Eu(BTP){sub 2}{sup 3+}] / [Eu(BTP){sub 3}{sup 3+}] ratio. (authors)

Excess europium content in Precambrian sedimentary rocks and continental evolution

Science.gov (United States)

Jakes, P.; Taylor, S. R.

1974-01-01

It is proposed that the europium excess in Precambrian sedimentary rocks, relative to those of younger age, is derived from volcanic rocks of ancient island arcs, which were the source materials for the sediments. Precambrian sedimentary rocks and present-day volcanic rocks of island arcs have similar REE patterns, total REE abundances, and excess Eu, relative to the North American shale composite. The present upper crustal REE pattern, as exemplified by that of sediments, is depleted in Eu, relative to chondrites. This depletion is considered to be a consequence of development of a granodioritic upper crust by partial melting in the lower crust, which selectively retains europium.

Europium enabled luminescent nanoparticles for biomedical applications

Energy Technology Data Exchange (ETDEWEB)

Syamchand, S.S., E-mail: syamchand.ss@gmail.com; Sony, G., E-mail: emailtosony@gmail.com

2015-09-15

Lanthanide based nanoparticles are receiving great attention ought to their excellent luminescent and magnetic properties and find challenging biomedical applications. Among the luminescent lanthanide NPs, europium based NPs (Eu-NPs) are better candidates for immunoassay and imaging applications. The Eu-NPs have an edge over quantum dots (QDs) by means of their stable luminescence, long fluorescence lifetime, sharp emission peaks with narrow band width, lack of blinking and biocompatibility. This review surveys the synthesis and properties of a variety of Eu-NPs consolidated from different research articles, for their applications in medicine and biology. The exquisite luminescent properties of Eu-NPs are explored for developing biomedical applications such as immunoassay and bioimaging including multimodal imaging. The biomedical applications of Eu-NPs are mostly diagnostic in nature and mainly focus on various key analytes present in biological systems. The luminescent properties of europium enabled NPs are influenced by a number of factors such as the site symmetry, the metal nanoparticles, metal ions, quantum dots, surfactants, morphology of Eu-NPs, crystal defect, phenomena like antenna effect and physical parameters like temperature. Through this review we explore and assimilate all the factors which affect the luminescence in Eu-NPs and coil a new thread of parameters that control the luminescence in Eu-NPs, which would provide further insight in developing Eu-based nanoprobes for future biomedical prospects. - Highlights: • The review describes 14 major factors that influence the luminescence properties of europium enabled luminescent nanoparticles (Eu-NPs). • Surveys different types of europium containing nanoparticles that have been reported for their biomedical applications. • Eu-NPs are conveniently divided into four different categories, based on the type of the substrates involved. The four categories are (1) virgin Eu-substrate based NPs; (2

Europium enabled luminescent nanoparticles for biomedical applications

International Nuclear Information System (INIS)

Syamchand, S.S.; Sony, G.

2015-01-01

Lanthanide based nanoparticles are receiving great attention ought to their excellent luminescent and magnetic properties and find challenging biomedical applications. Among the luminescent lanthanide NPs, europium based NPs (Eu-NPs) are better candidates for immunoassay and imaging applications. The Eu-NPs have an edge over quantum dots (QDs) by means of their stable luminescence, long fluorescence lifetime, sharp emission peaks with narrow band width, lack of blinking and biocompatibility. This review surveys the synthesis and properties of a variety of Eu-NPs consolidated from different research articles, for their applications in medicine and biology. The exquisite luminescent properties of Eu-NPs are explored for developing biomedical applications such as immunoassay and bioimaging including multimodal imaging. The biomedical applications of Eu-NPs are mostly diagnostic in nature and mainly focus on various key analytes present in biological systems. The luminescent properties of europium enabled NPs are influenced by a number of factors such as the site symmetry, the metal nanoparticles, metal ions, quantum dots, surfactants, morphology of Eu-NPs, crystal defect, phenomena like antenna effect and physical parameters like temperature. Through this review we explore and assimilate all the factors which affect the luminescence in Eu-NPs and coil a new thread of parameters that control the luminescence in Eu-NPs, which would provide further insight in developing Eu-based nanoprobes for future biomedical prospects. - Highlights: • The review describes 14 major factors that influence the luminescence properties of europium enabled luminescent nanoparticles (Eu-NPs). • Surveys different types of europium containing nanoparticles that have been reported for their biomedical applications. • Eu-NPs are conveniently divided into four different categories, based on the type of the substrates involved. The four categories are (1) virgin Eu-substrate based NPs; (2

Accumulation of zirconium phosphate by a Serratia sp.: a benign system for the removal of radionuclides from aqueous flows.

Science.gov (United States)

Mennan, Claire; Paterson-Beedle, Marion; Macaskie, Lynne E

2010-10-01

Metal phosphate deposited enzymatically on Serratia sp. has been used successfully for the removal of radionuclides from aqueous flows. Previous studies using biogenic hydrogen uranyl phosphate (HUP) on Serratia sp. biofilm showed removal of 100% of (90)Sr, (137)Cs, and (60)Co via their intercalation into biogenic HUP crystals. Zirconium phosphates (ZrP) offer a potential non-toxic and non-radioactive alternative to HUP for water decontamination. A method was developed for biomanufacturing ZrP. Biogenic ZrP removed ca. 100% of Sr(2+) and Co(2+) (0.5 mM) from solutions to a molar ratio at saturation of ca. 1:0.6 for both Zr:Sr and Zr:Co. The potential for drinking water decontamination via bio-ZrP is discussed with respect to bio-HUP and also other commercially available materials.

Synthesis of xerogels with Europium impurities for dosimetric applications

International Nuclear Information System (INIS)

Rivera R, C.; Garcia R, F.J.; Yanez L, M. -

2007-01-01

The objective of this work is the obtaining xerogels in bundle of SiO 2 with europium impurities to low concentrations, with the objective of exploring their mechanical, optical and emission properties. The obtained xerogels was synthesized by means of the sol-gel technique, using water, TEOS and ethanol to a molar relationship 16:1:4 respectively, the europium was added by oxide via to the precursor solution and to catalyze the hydrolysis condensation reaction, its were added: nitric acid and hydrofluorhydric acid. Later on these mixtures were left to gel by 72 hours and under this same composition, but with different quantities of impurifying material (0.0, 0.01 and 0.05g of europium oxide), the materials were dried in a ramp of controlled temperature, from ambient temperature up to 120 C, some of these thermally tried materials were calcined at 500 and 800 C, being obtained in this way xerogels free of fractures, stable, porous and semi-transparent. The characterization of these materials includes: pH measurements and solutions viscosity during the gelation stage, as well as characterization of their optic properties by means of infrared spectroscopy, UV-vis and emission spectroscopy. The microhardness results show that these materials present smaller values to those corresponding of the corning glass, as well as a growing behavior with regard to the calcination temperatures of the material. (Author)

Phytoremediation of radionuclides: an emerging alternative

International Nuclear Information System (INIS)

Singh, Shraddha

2013-01-01

Proliferation of nuclear power industry, nuclear weapon testing, dismantling of existing nuclear weapons and occasional accidents have contributed to an enhancement in the level of radionuclides in the environment. The radionuclides due to their long half life and transfer through the food chain effect adversely to normal biological systems. Hence, it is essential to effectively remove the radionuclides from contaminated soils and solutions. Phytoremediation - the use of plants for remediation of toxic metals and radionuclides has been recognized as an aesthetically pleasing, low cost and environment friendly in situ method. Phytoremediation is an umbrella term which covers several plant based approaches. Plants have shown the potential of remediation of these radionuclides from spiked solutions, low level nuclear waste and soil. Various aspects of phytoremediation as well as potential of various plants for remediation of radionuclides will be discussed here. (author)

Fermi Surface and Antiferromagnetism in Europium Metal

DEFF Research Database (Denmark)

Andersen, O. Krogh; Loucks, T. L.

1968-01-01

of the nearly cubical part of the hole surface at P, and we also discuss the effects of the electron surface at H. Since it is likely that barium and europium have similar Fermi surfaces, we have presented several extremal areas and the corresponding de Haas-van Alphen frequencies in the hope that experimental...

Surfactant-impregnated activated carbon for enhanced adsorptive removal of Ce(IV) radionuclides from aqueous solutions

International Nuclear Information System (INIS)

Mahmoud, Mamdoh R.; Sharaf El-deen, Gehan E.; Soliman, Mohamed A.

2014-01-01

Highlights: • Activated carbon (AC) was impregnated in this work with CTAB and NaLS surfactants. • The materials were evaluated as a sorbent for adsorption of Ce(IV) radionuclides. • Adsorption capacity of AC–NaLS for Ce(IV) is two-times the capacity of AC. • The kinetic and equilibrium data are fitted to pseudo-second-order and D–R models. • The results suggest the applicability of surface modified AC for waste treatment. - Abstract: The surfactants cetyltrimethylammonium bromide (CTAB) and sodium lauryl sulfate (NaLS) were utilized for modifying the activated carbon’s surface. The materials were characterized using BET–N 2 , scanning electron microscope, and Fourier transform infrared (FT-IR) spectroscopy. Adsorption of Ce(IV) radionuclides from aqueous solutions by activated carbon (AC) and surfactant-impregnated AC was studied. The obtained data showed that adsorption of Ce(IV) is strongly dependent on the solution pH and AC–NaLS exhibits the widest pH-range of maximum removal. The experimental adsorption capacity of AC–NaLS (0.069 mmol/g) for Ce(IV) is found to be nearly twice greater than that of AC (0.036 mmol/g). The adsorption kinetics of Ce(IV) onto AC and AC–NaLS were analyzed by linear and non-linear fittings to the pseudo-first-order, pseudo-second-order and Elovich kinetic models. Of these models, the pseudo-second-order is the best kinetic expression for describing the experimental data. The diffusion studies indicated that adsorption of Ce(IV) radionuclides on AC and AC–NaLS is controlled by film diffusion. Linear and non-linear fittings of the adsorption equilibrium data for Ce(IV) onto AC and AC–NaLS revealed that the Dubinin–Radushkevich (D–R) isotherm model fits the experimental data better than Freundlich and Langmuir models. The values of adsorption free energy, E, calculated from both linear and non-linear methods suggested that Ce(IV) radionuclides are physically adsorbed onto AC and AC–NaLS

Temperature effects in the valence fluctuation of europium intermetallic compounds

International Nuclear Information System (INIS)

Menezes, O.L.T. de; Troper, A.; Gomes, A.A.

1978-03-01

A previously reported model for valence fluctuations in europium compound in order to account for thermal occupation effect. Experimental results are critically discussed and new experiments are suggested

Marine biogeochemistry of radionuclides

International Nuclear Information System (INIS)

Fowler, S.W.

1997-01-01

Radionuclides entering the ocean from runoff, fallout, or deliberate release rapidly become involved in marine biogeochemical cycles. Sources, sinks and transport of radionuclides and analogue elements are discussed with emphasis placed on how these elements interact with marine organisms. Water, food and sediments are the source terms from which marine biota acquire radionuclides. Uptake from water occurs by surface adsorption, absorption across body surfaces, or a combination of both. Radionuclides ingested with food are either assimilated into tissue or excreted. The relative importance of the food and water pathway in uptake varies with the radionuclide and the conditions under which exposure occurs. Evidence suggests that, compared to the water and food pathways, bioavailability of sediment-bound radionuclides is low. Bioaccumulation processes are controlled by many environmental and intrinsic factors including exposure time, physical-chemical form of the radionuclide, salinity, temperature, competitive effects with other elements, organism size, physiology, life cycle and feeding habits. Once accumulated, radionuclides are transported actively by vertical and horizontal movements of organisms and passively by release of biogenic products, e.g., soluble excreta, feces, molts and eggs. Through feeding activities, particles containing radionuclides are ''packaged'' into larger aggregates which are redistributed upon release. Most radionuclides are not irreversibly bound to such particles but are remineralized as they sink and/or decompose. In the pelagic zones, sinking aggregates can further scavenge particle-reactive elements thus removing them from the surface layers and transporting them to depth. Evidence from both radiotracer experiments and in situ sediment trap studies is presented which illustrates the importance of biological scavenging in controlling the distribution of radionuclides in the water column. (author)

A Preliminary Study of Europium Uptake by Yeast Cells. The Case of Kluveromyces Marxianus

International Nuclear Information System (INIS)

Anagnostopoulos, V.; Symeopoulos, B.

2008-01-01

The objective of the present work is an exploration of a cost effective recovery of lanthanides, either for minimizing the industrial processes losses, or for reasons related to Radioactive Waste Management. Specifically, the uptake of europium from aqueous solutions by Kluveromyces marxianus cells was studied. Moreover, this biotechnological approach turns out to be environmental friendly, considering that cells of Kluveromyces marxianus are readily available as wastes from food fermentation industries. Europium [ 152 Eu+ 154 Eu]-labelled solutions were used providing better accuracy and reproducibility of measurements, mainly in low concentration range. The effect of pH, contact time and europium initial concentration were investigated. Adsorption data were fitted to Langmuir and Freundlich sorption models and Scatchard plots were used to reveal the existence of at least two types of binding sites

Nuclear orientation experiments on the magnetic moments of europium and gadolinium nuclei

International Nuclear Information System (INIS)

Berg, F.G. van den.

1984-01-01

In this thesis, experimental results on the ground state nuclear magnetic moments of europium and gadolinium isotopes are presented. The nuclear orientation experiments were performed on europium and gadolinium nuclei embedded in several host lattices. Attention is paid to the hyperfine interactions of the ions. Nuclear moments are discussed in the context of nuclear shell model. The theoretical framework is described for nuclear structure and low temperature nuclear orientation. Furthermore, the experimental techniques, the technical arrangement of the orientation apparatus, the methods for radiative detection and the use of nuclear orientation thermometry are described. (Auth.)

White OLED with a single-component europium complex.

Science.gov (United States)

Law, Ga-Lai; Wong, Ka-Leung; Tam, Hoi-Lam; Cheah, Kok-Wai; Wong, Wing-Tak

2009-11-16

A new direction for white organic light-emitting devices is shown, fabricated from a novel europium complex; this single component contains a double emission center of bluish-green and red, combined to a give a pure white emission (CIE x = 0.34 and y = 0.35).

Uncertainties in measuring trace amounts of cobalt and europium with low-flux neutron activation analysis

Directory of Open Access Journals (Sweden)

Burnham Steven

2017-01-01

Full Text Available Neutron activation analysis is widely used for identification of elements and their quantities even in trace amounts in the samples of almost any type. The challenges in detecting trace amounts of particular elements are often associated with the neutron flux produced at the research reactors. Low-flux neutron activation analysis usually presents the biggest challenge when analyzing trace quantities of elements with lower magnitude of radiative capture cross-sections. In this paper, we present the methodology and the quantified uncertainties associated with the detection of trace amounts of cobalt and europium, using as an example concrete aggregates. Recent growing interest is in improving structural concrete (increasing its strength but reducing its activation in nuclear power plant environments. Aside from buildings, structural concrete is also used as a biological shield in nuclear power plant that become radioactive after exposure to neutron flux. Due to radiative capture interactions, artificial radionuclides are generated to high enough concentrations that classify concrete as low-level radioactive waste at the time of the plant's decommissioning. Disposal of this concrete adds to the expense of nuclear power plant financing and its construction. Three radionuclides, 60Co, 152Eu, and 154Eu, account for 99 % of total residual radioactivity of nuclear power plant decommissioned concrete. IAEA document RS-G-1.7, Application of the Concepts of Exclusion, Exemption, and Clearance, specifies clearance levels of radionuclides specific activities: a specific activity lower than 0.1 Bqg-1 for 60Co and 152Eu, and 154Eu allows for a concrete to be recycled after decommissioning of the nuclear power plant. Therefore, low-flux neutron activation analysis is used to test the detection limits of trace elements in samples of cement, coarse, and fine concrete aggregates. These samples are irradiated at the University of Utah's 100 kW TRIGA Reactor at

Proceedings of Soil Decon `93: Technology targeting radionuclides and heavy metals

Energy Technology Data Exchange (ETDEWEB)

1993-09-01

The principal objective for convening this workshop was to exchange ideas and discuss with scientists and engineers methods for removing radionuclides and/or toxic metals from soils. Over the years there have been numerous symposia, conferences, and workshops directed at soil remediation. However, this may be the first where the scope was narrowed to the removal of radionuclides and toxic metals from soils. The intent was to focus on the separation processes controlling the removal of the radionuclide and/or metal from soil. Its purpose was not intended to be a soil washing/leaching workshop, but rather to identify a variety or combination of processes (chemical, physical, and biological) that can be used in concert with the applicable engineering approaches to decontaminate soils of radionuclides and toxic metals. Abstracts and visual aids used by the speakers of the workshop are presented in this document.

Proceedings of Soil Decon '93: Technology targeting radionuclides and heavy metals

International Nuclear Information System (INIS)

1993-09-01

The principal objective for convening this workshop was to exchange ideas and discuss with scientists and engineers methods for removing radionuclides and/or toxic metals from soils. Over the years there have been numerous symposia, conferences, and workshops directed at soil remediation. However, this may be the first where the scope was narrowed to the removal of radionuclides and toxic metals from soils. The intent was to focus on the separation processes controlling the removal of the radionuclide and/or metal from soil. Its purpose was not intended to be a soil washing/leaching workshop, but rather to identify a variety or combination of processes (chemical, physical, and biological) that can be used in concert with the applicable engineering approaches to decontaminate soils of radionuclides and toxic metals. Abstracts and visual aids used by the speakers of the workshop are presented in this document

Extraction of europium with thenoyltrifluoroacetone into alcohol, ketone and ester solvents

International Nuclear Information System (INIS)

Akiba, K.; Kanno, T.

1980-01-01

The effect of solvent has been studied on the extraction of tris-thenoyltrifluoroacetone (TTA) chelate of europium(III). Donor-active solvents (S) greatly promote the extraction owing to the formation of solvate species EuA 3 .mS (m = 1,2). Linear relations were established between the distribution of ratios of europium (Dsub(Eu)) and the partition constants of TTA (Psub(HA)); log Dsub(Eu) (at a definite pA) = a log Psub(HA) + b, where constants a and b were empirically determined for each series of solvents. The regularity is interpreted in terms of dual roles of solvent as donor and as medium. (author)

Speciation of radionuclides in natural poly-electrolytes of milk and soils. Author-review of dissertation submitted for fulfillment of the scientific degree 'Philosophiae doctor' (Ph.D.)

International Nuclear Information System (INIS)

Gerhart, P.

1999-01-01

The object of this research was to follow the chemical speciation of added radionuclides Sr-85 or Sr-90, Tc-99, Cs-137, Eu-152, and native cations in cow milk, as well as Pb-212 as a radioactive indicator of lead. The possibility of decontamination of milk from the contaminants was investigated. Speciation of Sr-90 and Cs-137 in the humic acids (HA) was studied as well. Skimmed milk pectin was prepared, which was used to follow the speciation of added radionuclides in the milk. The process of membrane-less dialysis from milk to the pectin phase was rapid and associated with the 3.5 to 4.7 times preconcentration of the non-diffusible in the milk phase in 15 minutes. From the fresh skim bovine milk spiked with respective radionuclides dissolved in the Jenness-Koops buffer (simulating milk serum) and agitated with 4% w/w water solution of apple pectin, about 80% of cesium, 22% of strontium and less than 1.5% of europium was recovered with the pectin. The results indicated that pectin and milk behave according poly-electrolytes. Thus, distribution does not depend on the degree of esterification pectin within the uncertainty of the results. The kinetics of radionuclide distribution was sufficiently rapid even though the viscosity of milk strongly increased during the contact. The recovery of radionuclides into the pectin phase using the milk-pectin membrane-less dialysis allowed the determination of the fractions of diffusible species of radionuclides, depending upon the model of evaluation employed. The sorption of strontium with the simulated milk serum was 31% and that of cesium and europium 58% and 40% respectively. The behaviour of Pb-212 recalls that of trivalent elements. Speciation of fission products Sr-90, Tc-99, Cs-137 and Eu-152 in raw cow milk was studied using the high-performance size exclusion radio-chromatography. The technique of HP-SEC and HP-RSEC by Micro-aqua-gel column was used for identification of radiocesium and radiostrontium interaction with

Phytoremediation of soil contaminated with low concentrations of radionuclides

Energy Technology Data Exchange (ETDEWEB)

Entry, J A; Vance, N C; Hamilton, M A; Zabowski, D; Watrud, L S; Adriano, D C [Auburn University, Auburn, AL (United States). Dept. of Agronomy and Soils

1996-03-01

Ecsosytems throughout the world have been contaminated with radionuclides by above-ground nuclear testing, nuclear reactor accidents and nuclear power generation. Radioisotopes characteristics of nuclear fission, such as {sup 137}Cs and {sup 90}Sr, that are released into the environment can become more concentrated as they move up the food chain often becoming human health hazards. Natural environmental processes will redistribute long lived radionuclides that are released into the environment among soil, plants and wildlife. Numerous studies have shown that {sup 137}Cs and {sup 90}Sr are not removed from the top 0.4 metres of soil even under high rainfall, and migration rate from the top few centimetres of soil is slow. The top 0.4 meters of the soil is where plant roots actively accumulate elements. Since plants are known to take up and accumulate {sup 137}Cs and {sup 90}Sr, removal of these radionuclides from contaminated soils by plants could provide a reliable and economical method of remediation. One approach is to use fast growing plants inoculated with mycorrhizal fungi combined with soil organic amendments to maximize the plant accumulation and removal of radionuclides from contaminated soils, followed by harvest of above-ground portion of the plants. High temperature combustion would be used to oxidize plant material concentrating {sup 137}Cs and {sup 90}Sr in ash for disposal. When areas of land have been contaminated with radionuclides are large, using energy intensive engineering solutions to mediate huge volumes of soil is not feasible or economical. Plants are proposed as a viable and cost effective method to remove radionuclides from the soils that have been contaminated by nuclear testing and nuclear reactor accidents. 40 refs.

Effects of added uranium on the triboluminescent properties of europium dibenzoylmethide triethylammonium

International Nuclear Information System (INIS)

Fontenot, Ross S.; Hollerman, William A.; Bhat, Kamala N.; Aggarwal, Mohan D.

2013-01-01

The ability of a material to emit light upon fracture is known as triboluminescence. One of the few materials that emits triboluminescence in daylight is europium dibenzoylmethide triethylammonium (EuD 4 TEA). It has been shown that this material is 106% brighter than ZnS:Mn when excited by low speed impacts. In 2011, the authors of this paper found that replacing the traditional europium chloride with europium nitrate and changing the carrier solvent could both significantly affect the triboluminescent emission yield. While these changes provided a significant increase in yield, the emission was still not sufficient to be observed in bright daylight. In order to enhance the effect, a series of materials were added to the EuD 4 TEA to study the effects of “doping” on the triboluminescence yield. Results from this research showed that doping from a small number of materials, such as uranyl acetate, increased emission yield. This paper discusses the research that was completed on effects of the addition of uranyl acetate to EuD 4 TEA could increase the triboluminmescent emission yield. Results show that the added uranium does indeed increase emission yield when it is first synthesized. However, radiation emitted by the uranium also was found to damage the doped EuD 4 TEA, thus reducing the emitted triboluminescence over a period of time. - Highlights: ► Uranium doped europium dibenzoylmethide triethylammonium (EuD 4 TEA) was synthesized. ► Effects of uranium was studied for low velocity ( 4 TEA was determined.

Enantioselective cellular localisation of europium(iii) coordination complexes.

Science.gov (United States)

Frawley, Andrew T; Linford, Holly V; Starck, Matthieu; Pal, Robert; Parker, David

2018-01-28

The selective mitochondrial localisation of the Λ enantiomer of three different emissive europium(iii) complexes in NIH 3T3 and MCF7 cells contrasts with the behaviour of the Δ enantiomer, for which a predominant lysosomal localisation was observed by confocal microscopy. In each case, cell uptake occurs via macropinocytosis.

Structural and luminescence properties of europium(III)-doped zirconium carbonates and silica-supported Eu3+-doped zirconium carbonate nanoparticles

International Nuclear Information System (INIS)

Sivestrini, S.; Riello, P.; Freris, I.; Cristofori, D.; Enrichi, F.; Benedetti, A.

2010-01-01

The synthesis, morphology and luminescence properties of europium(III)-doped zirconium carbonates prepared as bulk materials and as silica-supported nanoparticles with differing calcination treatments are reported. Transmission electron microscopy and X-ray diffraction analyses have, respectively, been used to study the morphology and to quantify the atomic amount of europium present in the optically active phases of the variously prepared nanomaterials. Rietveld analysis was used to quantify the constituting phases and to determinate the europium content. Silica particles with an approximate size of 30 nm were coated with 2 nm carbonate nanoparticles, prepared in situ on the surface of the silica core. Luminescence measurements revealed the role of different preparation methods and of europium-doping quantities on the optical properties observed.

Influence of natural organic matter on the speciation of radionuclides in a geochemistry context

International Nuclear Information System (INIS)

Marang, L.

2007-09-01

The principal aim of this work is the study of the influence of natural organic matter, in particularly humic substances (HS), on the speciation of radionuclides (RN). The studied radionuclides are cobalt (II), europium (III) and uranium (VI). It has been shown that mobility and bioavailability of a metal are related to its speciation. The NICA-Donnan model describes metal ion binding to NOM: it accounts for NOM chemical heterogeneity, competition during binding and ionic strength effects. However the model has been calibrated with a limited number of experimental data for the RN. Indeed there is only a few speciation technique available for the study of the interactions RN-HS. Within the framework of this study, we have developed and optimised speciation technique (Flux Donnan Membrane Technique and the use of an un-solubilized humic acid) in order to acquire new experimental data, we have also studied the effect of the competition on RN speciation and finally we have tested the model capacity to predict the RN behavior in laboratory or in situ. (author)

Influence of natural organic matter on the speciation of radionuclides in a geochemistry context

International Nuclear Information System (INIS)

Marang, L.

2007-09-01

The principal aim of this work is the study of the influence of natural organic matter, in particularly humic substances (HS), on the speciation of radionuclides (RN). The studied radionuclides are cobalt (II), europium (III) and uranium (VI). It has been shown that mobility and bioavailability of a metal are related to its speciation. The NICA-Donnan model describes metal ion binding to NOM: it accounts for NOM chemical heterogeneity, competition during binding and ionic strength effects. However the model has been calibrated with a limited number of experimental data for the RN. Indeed there is only a few speciation techniques available for the study of the interactions RN-HS. Within the framework of this study, we have developed and optimised speciation technique (Flux Donnan Membrane Technique and the use of an insolubilized humic acid) in order to acquire new experimental data, we have also studied the effect of the competition on RN speciation and finally we have tested the model capacity to predict the RN behavior in laboratory or in situ. (author)

Preparation of modified polymer- Alumino silicate composite and their application in removal of some radionuclides from aqueous solutions

International Nuclear Information System (INIS)

El- Masry, E.H.

2012-01-01

Ion exchange is one of the most common and effective treatment methods for radioactive liquid waste. This technique is well developed and has been employed for many years in both the nuclear industry and in other industries. In this thesis polyacrylamide- zeolite and polyacrylamide- bentonite composites were prepared and characterized using advanced analytical techniques. The prepared materials were used as composite ion exchangers for removal of Cesium, Cobalt and Strontium ions from simulated waste solution. Effect of ph of the medium on the removal of aforementioned ions was investigated. The sorption kinetic was studied and the data were analyzed by different kinetic models which rivaled that the mechanism of the sorption processes is mainly controlled by pseudo-second order reaction, and particle diffusion might be involved in the sorption processes. The values of diffusion coefficient of the three metal ions were calculated and suggested that chemisorption was the predominated sorption mechanism. Several isotherm models were applied for the sorption, and thermodynamic parameters were determined. The positive values of enthalpy change, δH, for the three metal ions confirmed the endothermic nature of the sorption processes. The results indicated that the prepared materials can be used as efficient ion exchange materials for the removal of cesium, cobalt and strontium ions from simulated waste solution. In the present study, immobilization of polyacrylamide- zeolite and/ or polyacrylamide- bentonite composites loaded with cesium, cobalt and/or strontium radionuclides with Ordinary Portland Cement (OPC) has been carried out. Several factors affecting the characteristics of the final solidified waste product towards safe disposal such as mechanical strength and leaching behavior of the radioisotopes have been studied. The obtained results showed that the presence of polyacrylamide- zeolite and/ or polyacrylamide- bentonite composites in the cemented wastes

Selective separation of radionuclides from nuclear waste solutions with inorganic ion exchangers

International Nuclear Information System (INIS)

Lehto, J.; Harjula, R.

1999-01-01

Nuclear industry produces and stores large volumes of radioactive waste solutions. Removal of radionuclides from the solutions is an important and challenging task for two main reasons: reductions in the volumes of solidified waste, which have to be disposed of, and reductions in the radioactive discharges into the environment. Since the radioactive elements in most waste solutions are in trace concentrations and the waste solutions contain large excesses of inactive metal ions, highly selective separation methods are needed for the removal of radionuclides. A number of inorganic ion exchange materials are very selective to key radionuclides and they can play an important role in solving these problems. The spectrum of nuclear waste solutions is rather wide considering their radionuclide contents, concentrations of interfering salts and acidity/alkalinity. Therefore, several inorganic ions exchangers are needed for the removal of most harmful radionuclides from a variety of solutions. This paper discusses the use and requirements of inorganic ion exchange materials in nuclear waste management. Special attention is paid to the novel ion exchange materials developed in the Laboratory of Radiochemistry, University of Helsinki. (orig.)

Determination of europium content in Li_2SiO_3(Eu) by neutron activation analysis using Am-Be neutron source

International Nuclear Information System (INIS)

Naik, Yeshwant; Tapase, Anant Shamrao; Mhatre, Amol; Datrik, Chandrashekhar; Tawade, Nilesh; Kumar, Umesh; Naik, Haladhara

2016-01-01

Circulardiscs of Li_2SiO_3 doped with europium were prepared and a new activation procedure for the neutron dose estimation in a breeder blanket of fusion reactor is described. The amount of europium in the disc was determined by neutron activation analysis (NAA) using an isotopic neutron source. The average neutron absorption cross section for the reaction was calculated using neutron distribution of the Am-Be source and available neutron absorption cross section data for the "1"5"1Eu(n,γ)"1"5"2"mEu reaction, which was used for estimation of europium in the pallet. The cross section of the elements varies with neutron energy, and the flux of the neutrons in each energy range seen by the nuclei under investigation also varies. Neutron distribution spectrum of the Am-Be source was worked out prior to NAA and the effective fractional flux for the nuclear reaction considered for the flux estimation was also determined. - Highlights: • Lithium meta-silicate is breeder materials for a fusion reactor. • Europium is used for neutron dose estimation in a breeder blanket. • It is important to determine amount of europium in lithium meta-silicate. • Amount of europium in lithium meta-silicate was determined by neutron activation and off-line gamma spectrometry.

The removal of radionuclides from foodstuffs during technological treatment and culinary processing

International Nuclear Information System (INIS)

Perepelyatnikova, L.V.; Lazarev, N.M.; Ivanova, T.N.; Fedin, F.A.; Long, S.; Pollard, D.

1996-01-01

Comparative data on the efficiency of industrial and domestic processing techniques of plant and animal products, which reduce radionuclides content foodstuffs, are summarized. Methods, which provide the greatest decrease of radionuclides content in the final products with minimum losses of nutritional value, were identified

Study of the europium behavior in aqueous media; Estudio sobre el comportamiento del europio en medios acuosos

Energy Technology Data Exchange (ETDEWEB)

Fernandez R, E.; Jimenez R, M.; Solache R, M.; Martinez M, V. [Instituto Nacional de Investigaciones Nucleares, Departamento de Quimica, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

2000-07-01

Europium as waste can produce a pollution problem in water that is in contact with it, what would has a heavy environmental impacts, because of the possibilities of diffusion of these wastes from their place of confinement or storage until the geo and biosphere. The solution of such problem requires of a lot of knowledge over the behavior of several chemical elements such as europium in aqueous solutions. In this work it was used a low ion force (0.02 M). The data set will allow extrapolate the hydrolytic behavior of europium in too much minors ion force media, such as the ground waters, including in ion force zero.

The europium and praseodymium hydrolysis in a 2M NaCl environment

International Nuclear Information System (INIS)

Jimenez R, M.; Lopez G, H.; Solache R, M.; Rojas H, A.

1998-01-01

It was studied the europium and praseodymium hydrolysis in a 2M NaCl ion force environment at 303 K, through two methods: this one extraction with dissolvents (lanthanide-water-NaCl-dibenzoylmethane) in presence of a competitive ligand (diglycolic acid) and that one direct potentiometric titration, of soluble species, followed by a computer refining. The values of one or another techniques of the first hydrolysis constants obtained were similar, which demonstrates that the results are reliable. The set of data obtained on the stability constants of hydrolysis products allowed to draw up the distribution diagrams of chemical species, as europium as praseodymium in aqueous environment. (Author)

Radionuclides: Accumulation and Transport in Plants.

Science.gov (United States)

Gupta, D K; Chatterjee, S; Datta, S; Voronina, A V; Walther, C

Application of radioactive elements or radionuclides for anthropogenic use is a widespread phenomenon nowadays. Radionuclides undergo radioactive decays releasing ionizing radiation like gamma ray(s) and/or alpha or beta particles that can displace electrons in the living matter (like in DNA) and disturb its function. Radionuclides are highly hazardous pollutants of considerable impact on the environment, food chain and human health. Cleaning up of the contaminated environment through plants is a promising technology where the rhizosphere may play an important role. Plants belonging to the families of Brassicaceae, Papilionaceae, Caryophyllaceae, Poaceae, and Asteraceae are most important in this respect and offer the largest potential for heavy metal phytoremediation. Plants like Lactuca sativa L., Silybum marianum Gaertn., Centaurea cyanus L., Carthamus tinctorius L., Helianthus annuus and H. tuberosus are also important plants for heavy metal phytoremediation. However, transfer factors (TF) of radionuclide from soil/water to plant ([Radionuclide]plant/[Radionuclide]soil) vary widely in different plants. Rhizosphere, rhizobacteria and varied metal transporters like NRAMP, ZIP families CDF, ATPases (HMAs) family like P1B-ATPases, are involved in the radio-phytoremediation processes. This review will discuss recent advancements and potential application of plants for radionuclide removal from the environment.

An electrochemical approach for removal of radionuclidic contaminants of Eu from 153Sm for effective use in metastatic bone pain palliation.

Science.gov (United States)

Chakravarty, Rubel; Chakraborty, Sudipta; Khan, Mohammed Sahiralam; Ram, Ramu; Sarma, Haladhar Dev; Dash, Ashutosh

2018-03-01

Thermal neutron activation of 152 Sm [ 152 Sm(n,γ) 153 Sm] using natural or isotopically enriched (by 152 Sm) samarium target is the established route for production of 153 Sm used for preparation of 153 Sm-EDTMP for pain palliation in cancer patients with disseminated bone metastases. However, some long-lived radionuclidic contaminants of Eu, such as, 154 Eu (t ½ =8.6y) are also produced during the target activation process. This leads to detectable amount of Eu radionuclidic contaminants in patients' skeleton even years after administration with therapeutic doses of 153 Sm-EDTMP. Further, the presence of such contaminants in 153 Sm raises concerns related to radioactive waste management. The aim of the present study was to develop and demonstrate a viable method for large-scale purification of 153 Sm from radionuclidic contaminants of Eu. A radiochemical separation procedure adopting electroamalgamation approach has been critically evaluated. The influence of different experimental parameters for the quantitative removal radionuclidic contaminants of Eu from 153 Sm was investigated and optimized. The effectiveness of the method was demonstrated by purification of ~37 GBq of 153 Sm in several batches. As a proof of concept, 153 Sm-EDTMP was administered in normal Wistar rats and ex vivo γ-spectrometry of bone samples were carried out. After carrying out the electrolysis under the optimized conditions, the radionuclidic contaminants of Eu could not be detected in purified 153 Sm solution by γ-spectrometry. The overall yield of 153 Sm obtained after the purification process was >85%. The reliability of this approach was amply demonstrated in several batches, wherein the performance remained consistent. Ex vivo γ-spectrometry of bone samples of Wistar rats administered with 153 Sm-EDTMP (prepared using electrochemically purified 153 Sm) did not show photo peaks corresponding to radionuclidic contaminants of Eu. A viable electrochemical strategy for the large

Trivalent europium speciation in a room-temperature ionic liquid

International Nuclear Information System (INIS)

Mekki, S.

2006-10-01

Since the nuclear industry is playing an important role in the power production field, a relevant number of problems have been revealed. Indeed, high-level radioactive long-lived nuclear wastes present a real difficulty for nuclear wastes management. Minor actinides, which compose most of these wastes, will be radioactive for several thousands of years. For eventual disposal deep underground, their reprocessing needs to be optimized. The extraction processes used industrially to separate actinides and lanthanides from other metal species characterizing the spent nuclear fuel produce, nevertheless, enormous quantities of contaminated liquid wastes directly issued from the liquid/liquid extraction step. During the last decade, some room-temperature ionic liquid have been studied and integrated into industrial processes. The interest on this class of solvent came out from their 'green' properties (non volatile, non flammable, recyclable, etc...), but also from the variability of their physico-chemical properties (stability, hydrophobicity, viscosity) as a function of the RTIL chemical composition. Indeed, it has been shown that classical chemical industrial processes could be transferred into those media, even more improved, while a certain number of difficulties arising from using traditional solvent can be avoided. In this respect, it could be promising to investigate the ability to use room-temperature ionic liquid into the spent nuclear fuel reprocessing field. The aim of this thesis is to test the ability of the specific ionic liquid bumimTf 2 N to allow trivalent europium extraction. The choice of this metal is based on the chemical analogy with trivalent minor actinides Curium and Americium which are contributing the greatest part of the long-lived high-level radioactive wastes. Handling these elements needs to be very cautious for the safety and radioprotection aspect. Moreover, europium is a very sensitive luminescent probe to its environment even at the

Ferromagnetic semiconductor-metal transition in heterostructures of electron doped europium monoxide

Energy Technology Data Exchange (ETDEWEB)

Stollenwerk, Tobias

2013-09-15

In the present work, we develop and solve a self-consistent theory for the description of the simultaneous ferromagnetic semiconductor-metal transition in electron doped Europium monoxide. We investigate two different types of electron doping, Gadolinium impurities and Oxygen vacancies. Besides the conduction band occupation, we can identify low lying spin fluctuations on magnetic impurities as the driving force behind the doping induced enhancement of the Curie temperature. Moreover, we predict the signatures of these magnetic impurities in the spectra of scanning tunneling microscope experiments. By extending the theory to allow for inhomogeneities in one spatial direction, we are able to investigate thin films and heterostructures of Gadolinium doped Europium monoxide. Here, we are able to reproduce the experimentally observed decrease of the Curie temperature with the film thickness. This behavior is attributed to missing coupling partners of the localized 4f moments as well as to an electron depletion at the surface which leads to a reduction of the number of itinerant electrons. By investigating the influence of a metallic substrate onto the phase transition in Gadolinium doped Europium monoxide, we find that the Curie temperature can be increased up to 20%. However, as we show, the underlying mechanism of metal-interface induced charge carrier accumulation is inextricably connected to a suppression of the semiconductor-metal transition.

Ferromagnetic semiconductor-metal transition in heterostructures of electron doped europium monoxide

International Nuclear Information System (INIS)

Stollenwerk, Tobias

2013-09-01

In the present work, we develop and solve a self-consistent theory for the description of the simultaneous ferromagnetic semiconductor-metal transition in electron doped Europium monoxide. We investigate two different types of electron doping, Gadolinium impurities and Oxygen vacancies. Besides the conduction band occupation, we can identify low lying spin fluctuations on magnetic impurities as the driving force behind the doping induced enhancement of the Curie temperature. Moreover, we predict the signatures of these magnetic impurities in the spectra of scanning tunneling microscope experiments. By extending the theory to allow for inhomogeneities in one spatial direction, we are able to investigate thin films and heterostructures of Gadolinium doped Europium monoxide. Here, we are able to reproduce the experimentally observed decrease of the Curie temperature with the film thickness. This behavior is attributed to missing coupling partners of the localized 4f moments as well as to an electron depletion at the surface which leads to a reduction of the number of itinerant electrons. By investigating the influence of a metallic substrate onto the phase transition in Gadolinium doped Europium monoxide, we find that the Curie temperature can be increased up to 20%. However, as we show, the underlying mechanism of metal-interface induced charge carrier accumulation is inextricably connected to a suppression of the semiconductor-metal transition.

Determination of Europium by fluorescence using pyrrolidinium based task specific ionic liquid

International Nuclear Information System (INIS)

Kumar, Satendra; Gayan, Siuli Maji; Sankaran, K.

2012-01-01

Determination of lanthanides using fluorescence is a major challenge in aqueous medium due to their poor molar absorptivities and low quantum yield. To overcome these problems, ligand sensitized fluorescence has been widely used for trace level detection of lanthanides in solutions. Recently, ionic liquid a non aqueous medium has been used to observe the fluorescence of lanthanides. In this work we have used pyrrolidinium based ionic liquid for the study of europium fluorescence. The ionic liquid (bmpyr)(BA) was prepared using the metathesis reaction involving 1-butyl,1-methyl pyrrolidinium chloride (bmpyr)(CI). (bmpyr)(Cl) crystals and silver benzoate were added according to their mole equivalents in methanol and stirred for 4 hrs. The filtrate was concentrated using a rotary evaporator, dried for 10 h at room temperature, and then for 40 h at 105℃under reduced pressure. This results in a white crystalline hygroscopic solid which was characterized by FT-lR spectroscopy. The yield of the product was ∼ 95%. Butyl-1, methyl pyrrolidinium bis(trifluoromethanesulfonyl)amide (bmpyr)(TF 2 N) is used for dissolve and dilute (bmpyr)(BA) and fluorescence and life time of Eu 3+ were obtained. For the concentration of Eu 3+ used in this study (2x10 -7 M), the optimum concentration of the sensitizing ionic liquid was found to be 10 -4 M. An enhancement factor of about 32000 was found in this ionic liquid compare to aqueous medium. Fluorescence life time of europium in this ionic liquid is 1100 μs which is ten times more than the life time of europium in aqueous medium (110 μs), indicating a reduction in the rates of non-radiative processes which was provided by the ionic liquid. This study leads to detection of europium in ppb level. (author)

Synthesis of mixed ligand europium complexes: Verification of predicted luminescence intensification

International Nuclear Information System (INIS)

Lima, Nathalia B.D.; Silva, Anderson I.S.; Gonçalves, Simone M.C.; Simas, Alfredo M.

2016-01-01

Mixed ligand europium complexes are predicted to be more luminescent than what would be expected from their corresponding repeating ligand compounds according to a conjecture recently advanced by our research group; a conjecture that has already been validated for strongly luminescent europium complexes. In this article, we seek to further verify the validity of this conjecture for complexes which are much more symmetric, and which thus display lower levels of luminescence. Accordingly, we synthesized complexes Eu(DBM) 3 (L) 2 , and all novel mixed ligand combinations Eu(DBM) 3 (L,L') with L and L' equal to DBSO, PTSO, and TPPO. The syntheses were carried out via displacement reactions from the starting complex Eu(DBM) 3 (H 2 O) 2 , passing through the intermediates Eu(DBM) 3 (L) 2 and finally, by displacement of L by L', arriving at Eu(DBM) 3 (L,L'). The ligands L obey the following order of displacement TPPO>PTSO>DBSO>H 2 O, which had been previously described by our group. In the present article, we further show that this displacement order could have been predicted by Sparkle/RM1 thermochemical calculations. Subsequently, we determined the radiative decay rates, A rad , for all six compounds by photophysical measurements. As expected, results show that the measured A rad values for all novel mixed ligand complexes are larger than the average of the A rad values for the corresponding repeating ligand coordination compounds. In conclusion, the present article does broaden the scope of our conjecture, which enunciates that an increase in the diversity of ligands around the europium ion tends to intensify the luminescence. - Highlights: • Mixed ligand europium complexes are predicted to be more luminescent than repeating ligand ones. • Radiative decay rates increase with structural coordination asymmetry. • The non-ionic ligands displacement order in substitution reactions is TPPO>PTSO>DBSO>H 2 O. • Sparkle/RM1 correctly predicts the

Technetium removal from aqueous wastes

International Nuclear Information System (INIS)

Fletcher, P.A.; Jones, C.P.; Junkison, A.R.; Turner, A.D.; Kavanagh, P.R.

1992-03-01

The research discussed in this report has compared several ''state of the art'' techniques for the removal of traces of the radionuclide, technetium, from aqueous wastes. The techniques investigated were: electrochemical reduction to an insoluble oxide, electrochemical ion exchange, seeded ultrafiltration and chemical reduction followed by filtration. Each technique was examined using a simulant based upon the waste generated by the Enhanced Actinide Removal Plant (EARP) at Sellafield. The technique selected for further investigation was direct electrochemical reduction which offers an ideal route for the removal of technetium from the stream (DFs 10-100) and can be operated continuously with a low power consumption 25 kW for the waste generated by EARP. Cell designs for scale up have been suggested to treat the 1000m 3 of waste produced every day. Future work is proposed to investigate the simultaneous removal of other key radionuclides, such as ruthenium, plutonium and cobalt as well as scale up of the resulting process and to investigate the effect of these other radionuclides on the efficiency of the electrochemical reduction technique for the removal of technetium. Total development and full scale plant costs are estimated to be of the order of 5 pounds - 10M, with a time scale of 5 -8 years to realisation. (author)

TESTING OF A FULL-SCALE ROTARY MICROFILTER FOR THE ENHANCED PROCESS FOR RADIONUCLIDES REMOVAL

Energy Technology Data Exchange (ETDEWEB)

Herman, D; David Stefanko, D; Michael Poirier, M; Samuel Fink, S

2009-01-01

Savannah River National Laboratory (SRNL) researchers are investigating and developing a rotary microfilter for solid-liquid separation applications in the Department of Energy (DOE) complex. One application involves use in the Enhanced Processes for Radionuclide Removal (EPRR) at the Savannah River Site (SRS). To assess this application, the authors performed rotary filter testing with a full-scale, 25-disk unit manufactured by SpinTek Filtration with 0.5 micron filter media manufactured by Pall Corporation. The filter includes proprietary enhancements by SRNL. The most recent enhancement is replacement of the filter's main shaft seal with a John Crane Type 28LD gas-cooled seal. The feed material was SRS Tank 8F simulated sludge blended with monosodium titanate (MST). Testing examined total insoluble solids concentrations of 0.06 wt % (126 hours of testing) and 5 wt % (82 hours of testing). The following are conclusions from this testing.

Temperature dependences in electron-stimulated desorption of neutral europium

CERN Document Server

Ageev, V N; Madey, T E

2003-01-01

The electron-stimulated desorption (ESD) yield for neutral europium (Eu) atoms from Eu layers adsorbed on oxygen-covered tungsten surfaces has been measured as a function of electron energy, europium coverage and degree of oxidation of tungsten, with an emphasis on effects of substrate temperature. The measurements have been carried out using a time-of-flight method and surface ionization detector. We expand on an earlier report, and compare ESD of multivalent Eu with ESD of monovalent alkali atoms, studied previously. The Eu atom ESD is a complicated function of Eu coverage, electron energy and substrate temperature. In the coverage range 0.05-0.35 monolayer (ML), overlapping resonant-like Eu atom yield peaks are observed at electron energies E sub e of 36 and 41 eV that might be associated with Eu or W shallow core level excitations. Additional resonant-like peaks are seen at E sub e of 54 and 84 eV that are associated with W 5p and 5s level excitations. The Eu atom yield peaks at 36 and 41 eV are seen only...

Magneto-optical studies of valence instability in europium and terbium phosphors

Czech Academy of Sciences Publication Activity Database

Rodrigues, L.C.v.; Hölsä, J.; Brito, H.F.; Maryško, Miroslav; Matos, J.R.; Paturi, P.; Rodrigues, R.V.; Lastusaari, M.

2016-01-01

Roč. 170, Feb (2016), 701-706 ISSN 0022-2313 Institutional support: RVO:68378271 Keywords : valence * europium * terbium * oxysulfide and -sulfate * phosphors * paramagnetic susceptibility Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.686, year: 2016

Application of radionuclide imaging in hyperparathyroidism

International Nuclear Information System (INIS)

Zheng Yumin; Yan Jue

2011-01-01

Hyperparathyroidism (HPT) is overactivity of the parathyroid glands resulting in excess production of parathyroid hormone. Excessive parathyroid hormone secretion may be due to problems in the glands themselves, or may be secondary HPT. The diagnosis is mainly based on the patient's medical history and biochemical tests. The best treatment nowadays is surgical removal of the overactive parathyroid glands or adenoma. The imaging methods for the preoperative localization diagnosis include radionuclide imaging,ultrasonography, CT, MRI, etc. This article was a summary of HPT radionuclide imaging. (authors)

Sorbent application on the base of chitosan for radionuclides separation

International Nuclear Information System (INIS)

Pivarciova, L.

2016-01-01

Radioactive waste contains enormous amounts of radionuclides, which pollute the environment and can cause serious chemical and radiological toxicity threats to lower and higher living organism. Alternative process for the removal of heavy metal ions and radionuclides is sorption, which utilizes various certain natural materials of biological origin. Amino-polysaccharide-based sorbents e.g. chitosan represent suitable materials for binding of metal oxo-anion species because of numerous functional groups -OH and -NH_2 because of their suitable H-bond donor and acceptor sites. The sorbents on the base chitosan prepared through chemical modification were used for removal and separation certain radionuclides from aqueous media. The aim of this work was the study of physicochemical properties of prepared sorbents. The specific surface of sorbents was characterized with BET methods. Point of zero charge was identified with potentiometric titration. The size of particles and shape of sorbents were determined by scanning electron microscope. The sorption experiments for selected radionuclides were conducted under static and dynamic conditions. The effect of various parameters on the sorption "9"9"mTc, "6"0Co and the effect of pH on the separation of radionuclide mixture in the solution were studied. (author)

Luminescence properties of europium (III) cryptates trapped in sol-gel glass

International Nuclear Information System (INIS)

Zaitoun, M.A.; Kim, T.; Jaradat, Q.M.; Momani, K.; Qaseer, H.A.; El-Qisairi, A.K.; Qudah, A.; Radwan, N.E.

2008-01-01

The Lanthanide complexes Eu-2.2.1 and Eu-2.2.2 were synthesized and then incorporated into silica based transparent organic-inorganic hybrid material by the sol-gel method as an example of how doped xerogel materials are emerging as an important means of producing new materials. The produced gels were diagnosed to monitor emission spectra of the luminescent trivalent europium (Eu 3+ ) complexes; emissions were compared to those for gels containing uncomplexed Eu 3+ . Results of the experiments (emission and lifetimes) concerning the coordination sphere composition showed that a cryptand ligand with aromatic groups (short range effect) and the hydrophobic gel host (long range effect) settle efficient action in the antenna effect and isolate the central ion from efficient quenchers, as e.g. water molecules. Each ligand imposed a distinct splitting pattern on the europium emission bands that helps identify them

Selective flotation for the removal of radionuclides from contaminated soil

International Nuclear Information System (INIS)

Miller, J.D.; Yu, Q.; Lu, Y.Q.

1995-01-01

Low-level radioactive contaminated soils (10--500 pci/gm) created by defense-related activities at certain Superfund sites, such as Nevada Test Site (NTS), is a current environmental concern. Many of these contaminated sites may require appropriate cleanup and restoration, which could cost billions of dollars and put tremendous pressure on limited financial resources. Therefore, the development of a selective flotation process to separate such radionuclides from contaminated soils should be considered. In this study, both a pure depleted UO 2 sample and three synthetic UO 2 /soil mixtures were used to evaluate surface chemistry features and to examine the possibility for the flotation of fine UO 2 particles from selected soils. It was intended that this model system would be a reasonable representation of contaminated soils such as those found the Nevada Test Site which are reported to be contaminated by PuO 2 fallout. The effect of reagent schedule, particle size distribution, and surface charge are discussed with respect to the flotation separation of the UO 2 /soil mixtures. It was found that both commercial fatty acids and reagent grade sodium oleate are effective collectors for UO 2 flotation provided the pH is adjusted to the range of pH 8--9. The bench-scale flotation results successfully demonstrated that froth flotation technology can be used to remove UO 2 from such model contaminated soils with appropriate flotation chemistry conditions which depend on the soil characteristics and other pretreatment procedures

The Preparation and Thermodynamics of Europium Dicarbide; Preparation et Thermodynamique du Bicarbure d'Europium; Poluchenie i termodinamicheskie svojstva dikarbida evropiya; Preparacion y Termodinamica del Dicarburo de Europio

Energy Technology Data Exchange (ETDEWEB)

Gebelt, R. E. [Oklahoma State University, Stillwater, OK (United States); Eick, H. A. [Michigan State University, East Lansing, MI (United States)

1966-01-15

Europium dicarbide has been prepared by the reaction of europium metal and graphite in a stainless steel bomb. Chemical analysis indicates an average composition of the product of EuC{sub 1.87{+-}0.07}. X-ray powder diffraction analysis shows the compound to be of body-centred tetragonal symmetry, space group D{sup 17}{sub 4}n-14/mm , with lattice parameters: a{sub 0} = 4.045 A; c{sub 0} = 6.645 A. Vapour phase chromatographic analysis indicates that 98% of the gaseous product of acid hydrolysis of europium dicarbide is the hydrocarbon acetylene. These analytical data, together with the lattice parameters, indicate that europium dicarbide resembles alkaline earth dicarbides more than it resembles the other lanthanon dicarbides. The vaporization of europium dicarbide over the temperature range 1130 to 1600 Degree-Sign K was investigated by the Knudsen effusion method. The effusate was either collected and analysed chemically or observed with a time-of-flight mass spectrometer. Thedata presented here are based predominantly on the massspectro- metric observations since they yielded more reproducible data than the collection technique. Gaseous europium dicarbide and europium, in concentrations of 1 and 99%respectively, were found in the effusate. Instrument limitations prevented determination of the concentration of the gaseous dicarbide as a function of temperature. Calibration of the mass spectrometer with silver permitted the calculation of the pressures corresponding to the observed ion intensities. An empirical equation was fitted to the data for europium by the method of least squares. From the second law of thermodynamics the following values were calculated for the reaction: EuC{sub 2} Rightwards-Harpoon-Over-Leftwards-Harpoon Eu(g) + 2C (graphite); {Delta}H{sup 0}{sub 298} = 51.09{+-}1.42kcal/mole; {Delta}H{sup 0}{sub 298} = 18.43 {+-} 1.75 e.u. Values of the free energy function for EuC{sub 2}(s) were estimated and combined with published data to yield for

Highly specific ''sensing'' of tryptophan by a luminescent europium(III) complex

Energy Technology Data Exchange (ETDEWEB)

Stubenrauch, Jan A.; Mevissen, Christian; Schulte, Marie F.; Bochenek, Steffen; Albrecht, Markus [RWTH Univ. Aachen (Germany). Inst. fuer Organische Chemie; Subramanian, Palani S. [Central Salt and Marine Chemicals, Research Institute (CSRI), Gujarat (India)

2016-07-01

The europium(III) complex 1-Cl{sub 3} (S,S-2,2{sup '}-(((1,10-phenanthroline-2,9-diyl)bis(methanylylidene))bis (azanylyliden e))bis(3-methylbutanamide)europiumtrichloride) undergoes, only in the presence of the amino acid tryptophan, a change of emission at 615 nm. In the presence of few equivalents of tryptophan, emission of the europium complex is enhanced while it disappears upon addition of large amounts. This behavior can be assigned to displacement of the sensitizing phenanthroline ligand of 1-Cl{sub 2} x Trp in the latter case.

Enthalpies of formation of europium alkoxides: What lessons can be drawn from them

International Nuclear Information System (INIS)

Branco, Joaquim B.; Carretas, José M.; Epple, Matthias; Cruz, Adelaide; Pires de Matos, A.; Leal, João Paulo

2014-01-01

Highlights: • First time measurement of europium(II) alkoxides enthalpy of formation. • Calculation of alkoxides thermochemical radii and M–O distances in this environment. • Comparison of experimental EXAFS distance with the calculated ones. • Hints on the type of bond existing in these compounds. • Correlation of bond type and possible use as catalysts. - Abstract: The synthesis and characterization of two europium alkoxides, Eu(OCH 3 ) 2 and Eu(OC 2 H 5 ) 2 , were described. For the first time the enthalpies of formation of divalent lanthanide alkoxides were determined by using reaction-solution calorimetry. The values obtained are Δ f H 0 [Eu(OCH 3 ) 2 ,cr] = −850.5 ± 5.0 kJ/mol and Δ f H 0 [Eu(OC 2 H 5 ) 2 ,cr] = −902.5 ± 5.5 kJ/mol, respectively. Since these compounds have a large use as catalysts or catalysts precursors, the first step of the reaction of them with CO 2 was addressed, which permits to have an idea of the kind of bond involved in those compounds. Moreover, insertion of CO 2 in the europium oxygen bond and formation of metal carboxylate complexes, is in both cases presumably bidentate

Fluorimetric determination of samarium(III) and europium(III) in neodymium oxide by separation with a resin column

Energy Technology Data Exchange (ETDEWEB)

Shaorong Liu; Jian Meng (Beijing Research Institute of Chemical Engineering and Metallurgy (China)); Wenhua Liu (General Research Institute for Non-Ferrous Metals (China))

1992-08-24

When thenoyltrifluoroacetone-phenanthroline-Triton X-100 is used to determine samarium(III) and europium(III) fluorimetrically, only a limited amount of neodymium(III) can be tolerated. By using an on- line separation which can partially separate neodymium(III) from samarium(III), a practical and convenient method was developed to detect samarium(III) at concentrations >0.05% and europium(III) at concentrations >0.005% in neodymium oxide. (author). 7 refs.; 4 figs.; 3 tabs.

Fluorimetric determination of samarium(III) and europium(III) in neodymium oxide by separation with a resin column

International Nuclear Information System (INIS)

Shaorong Liu; Jian Meng; Wenhua Liu

1992-01-01

When thenoyltrifluoroacetone-phenanthroline-Triton X-100 is used to determine samarium(III) and europium(III) fluorimetrically, only a limited amount of neodymium(III) can be tolerated. By using an on- line separation which can partially separate neodymium(III) from samarium(III), a practical and convenient method was developed to detect samarium(III) at concentrations >0.05% and europium(III) at concentrations >0.005% in neodymium oxide. (author). 7 refs.; 4 figs.; 3 tabs

Lanthanum and yttrium oxysulfides activated by europium: (Ln1-x Eux)2 O2 S - Synthesis and characterization

International Nuclear Information System (INIS)

Luiz, J.M.

1989-01-01

The synthesis of lanthanum and yttrium oxysulfides activated by europium were obtained by thermal decomposition of lanthanum and yttrium oxalates doped with europium, under an argon and sulphur atmosphere. The thermal decomposition of these compounds is studied by differential thermal analysis (DTA). The characterization of these oxysulfides were made by chemical analyses, infrared spectroscopy, X-ray diffraction, scanning electron microscopy and emission spectroscopy. (M.V.M.)

The migrant 152Eu as europium humate

International Nuclear Information System (INIS)

Klotz, D.

2001-01-01

Europium was used as a representative of the lanthanide group in the migration experiments in underground water. These 14 elements, with the atomic numbers of 58 (cerium) through 71 (lutetium) are quite similar in their chemical characteristics, and all of them will form metal-humate complexes with humic acids via proton exchange groups. Apart from the concentration, chemical composition and structure, also the particle size of these metal humates will vary strongly as it is dependent on the geochemistry and geophysics of the underground systems [de

Is the stoichiometry of the europium nitrate complexes with neutral organophosphorus extractants be anticipated?

International Nuclear Information System (INIS)

Beudaert, Ph.; Lamare, V.; Wipff, G.

2001-01-01

Molecular dynamics simulations have been performed in water on europium nitrate complexes with three neutral organophosphorus extractants (TBP, TPPO and CMPO) in order to determine on what criteria it is possible to obtain by simulations the experimental 1:3 stoichiometry in organic solution. This stoichiometry was investigated by progressive saturation of the cation coordination sphere. When the nitrate counter-ions are bidentate, the 1:3 stoichiometry corresponds to the degree of saturation where the interaction energy between europium and water becomes repulsive. Beyond this stoichiometry, complexes with TPPO and CMPO are unstable, although a 1:4 complex with TBP may exist but its formation appears to be energetically unfavored. (author)

RADIONUCLIDE DISPERSION RATES BY AEOLIAN, FLUVIAL, AND POROUS MEDIA TRANSPORT

International Nuclear Information System (INIS)

Walton, J.; Goodell, P.; Brashears, C.; French, D.; Kelts, A.

2005-01-01

Radionuclide transport was measured from high grade uranium ore boulders near the Nopal I Site, Chihuahua, Mexico. High grade uranium ore boulders were left behind after removal of a uranium ore stockpile at the Prior High Grade Stockpile (PHGS). During the 25 years when the boulder was present, radionuclides were released and transported by sheetflow during precipitation events, wind blown resuspension, and infiltration into the unsaturated zone. In this study, one of the boulders was removed, followed by grid sampling of the surrounding area. Measured gamma radiation levels in three dimensions were used to derive separate dispersion rates by the three transport mechanisms

RADIONUCLIDE DISPERSION RATES BY AEOLIAN, FLUVIAL, AND POROUS MEDIA TRANSPORT

Energy Technology Data Exchange (ETDEWEB)

J. Walton; P. Goodell; C. Brashears; D. French; A. Kelts

2005-07-11

Radionuclide transport was measured from high grade uranium ore boulders near the Nopal I Site, Chihuahua, Mexico. High grade uranium ore boulders were left behind after removal of a uranium ore stockpile at the Prior High Grade Stockpile (PHGS). During the 25 years when the boulder was present, radionuclides were released and transported by sheetflow during precipitation events, wind blown resuspension, and infiltration into the unsaturated zone. In this study, one of the boulders was removed, followed by grid sampling of the surrounding area. Measured gamma radiation levels in three dimensions were used to derive separate dispersion rates by the three transport mechanisms.

Particle count monitoring of reverse osmosis water treatment for removal of low-level radionuclides

International Nuclear Information System (INIS)

Moritz, E.J.; Hoffman, C.R.; Hergert, T.R.

1995-01-01

Laser diode particle counting technology and analytical measurements were used to evaluate a pilot-scale reverse osmosis (RO) water treatment system for removal of particulate matter and sub-picocurie low-level radionuclides. Stormwater mixed with Waste Water Treatment Plant (WWTP) effluent from the Rocky Flats Environmental Technology Site (RFETS), formerly a Department of Energy (DOE) nuclear weapons production facility, were treated. No chemical pretreatment of the water was utilized during this study. The treatment system was staged as follows: multimedia filtration, granular activated carbon adsorption, hollow tube ultrafiltration, and reverse osmosis membrane filtration. Various recovery rates and two RO membrane models were tested. Analytical measurements included total suspended solids (TSS), total dissolved solids (TDS), gross alpha (α) and gross beta (β) activity, uranium isotopes 233/234 U and 238 U, plutonium 239/240 Pu, and americium 241 Am. Particle measurement between 1--150 microns (μ) included differential particle counts (DPC), and total particle counts (TPC) before and after treatment at various sampling points throughout the test. Performance testing showed this treatment system produced a high quality effluent in clarity and purity. Compared to raw water levels, TSS was reduced to below detection of 5 milligrams per liter (mg/L) and TDS reduced by 98%. Gross α was essentially removed 100%, and gross β was reduced an average of 94%. Uranium activity was reduced by 99%. TPC between 1-150μ were reduced by an average 99.8% to less than 1,000 counts per milliliter (mL), similar in purity to a good drinking water treatment plant. Raw water levels of 239/240 Pu and 241 Am were below reliable quantitation limits and thus no removal efficiencies could be determined for these species

Luminescent properties of Europium(III) nitrate with 1,10-phenantroline and cinnamic acid in light - Transforming polymer materials

Science.gov (United States)

Kalinovskaya, I. V.; Zadorozhnaya, A. N.

2018-04-01

Influence of cinnamic acid on the luminescent properties of the europium(III) nitrate with 1,10-phenantroline in a polymer materials was studied. It was shown that combined use of these rare earth complexes leads to intense luminescence in the 400-700 nm region. Samples containing polymer europium nitrate with 1,10-phenantroline and cinnamic acid at a molar ratio of 1:2,0 had the maximum luminescence intensity and photostability.

Removal of contaminated asphalt layers by using heat generating powder metallic systems

International Nuclear Information System (INIS)

Barinov, A.S.; Karlina, O.K.; Ojovan, M.I.

1996-01-01

Heat generating systems on the base of powder metallic fuel were used for the removal of contaminated asphalt layers. Decontamination of spots which had complex geometric form was performed. Asphalt layers with deep contamination were removed essentially all radionuclides being retained in asphalt residue. Only a small part (1 - 2 %) of radionuclides could pass to combustion slag. No radionuclides were detected in aerosol-gas phase during decontamination process

The glass block site radionuclide migration study

International Nuclear Information System (INIS)

Killey, R.W.D.; Champ, D.R.

1990-01-01

In 1960 25 nepheline syenite glass blocks containing 14 TBq of mixed fission products in 50 kg of glass were placed below the water table in a shallow sand aquifer at Chalk River Laboratories. Experimental studies undertaken at the site since 1960 have included detailed mapping of the plume of 90 Sr in 1963, 1966 and 1971. Mathematical modeling studies have employed the radiostrontium plume data in determining the split between ion exchange and chemisorption of 90 Sr, and in obtaining reaction rate data for chemisorption. The distribution of 137 Cs on downgradient soils was mapped in 1963 and 1979. An extended plume of low-level 137 Cs contamination observed in the 1979 study prompted an investigation of the role of particulate materials in radionuclide transport. IN 1983, large volume groundwater sampling and separation of cationic, anionic, and neutral dissolved species, as well as particulates, detected anionic and cationic dissolved europium isotopes (154 and 155), and again encountered particulate 137 Cs. A variety of investigations of cesium and strontium sorption have provided a data base on sediment mineralogy, particle surface features, and information on sorption sites and processes. The year 1990 saw the inauguration of a three-year program to update investigations of radionuclide release, transport, and sorption at the glass block site. The first stage of the program has been a detailed definition and simulation of the hydrogeologic setting. Plume mapping and aqueous speciation studies are in progress. This paper summarizes past investigations, reviews the status of the current program, and discusses components of future studies, including investigations of sediment sorption mechanisms. (Author) (17 refs., 8 figs.)

Theoretical spectroscopic study of the conjugate microcystin-LR-europium cryptate

Energy Technology Data Exchange (ETDEWEB)

Santos, Julio G.; Dutra, Jose Diogo L.; Costa Junior, Nivan B. da; Freire, Ricardo O., E-mail: rfreire@ufs.br [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Quimica; Alves Junior, Severino; Sa, Gilberto F. de [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Quimica Fundamental

2013-02-15

In this work, theoretical tools were used to study spectroscopic properties of the conjugate microcystin-LR-europium cryptate. The Sparkle/AM1 model was applied to predict the geometry of the system and the INDO/S-CIS model was used to calculate the excited state energies. Based on the Judd-Ofelt theory, the intensity parameters were predicted and a theoretical model based on the theory of the 4f-4f transitions was applied to calculate energy transfer and backtransfer rates, radiative and non-radiative decay rates, quantum efficiency and quantum yield. A detailed study of the luminescent properties of the conjugate Microcystin-LR-europium cryptate was carried out. The results show that the theoretical quantum yield of luminescence of 23% is in good agreement with the experimental value published. This fact suggests that this theoretical protocol can be used to design new systems in order to improve their luminescence properties. The results suggest that this luminescent system may be a good conjugate for using in assay ELISA for detection by luminescence of the Microcystin-LR in water. (author)

Synthesis, characterization and fluorescence studies of a novel europium complex based sensor

International Nuclear Information System (INIS)

Li Bin; Chen Qiuyun; Wang Yachen; Huang Jing; Li Yang

2010-01-01

A novel europium(III) complex was synthesized using TTA (α-thenoyltrifluoroacetone) as the first ligand and H 2 bpdc (2,2'-bipyridine-3,3'-dicarboxylate) as the second ligand. Elemental analysis, thermal analysis, IR and UV-vis spectrum and fluorescence spectrum of the europium(III) complex were carried out. A characteristic Eu 3+ fluorescence emission was observed in ethanol-water (1:1) solution, indicating that the complex is stable in solution and the emission of Eu(III) ions was not influenced by the water molecules. The fluorescence emission of the complex was quenched completely by the Co 2+ and Fe 3+ ions, but the quenched emission was recovered in the presence of glycine. Moreover, the Eu 3+ emission was very sensitive to pH, so the complex can be used as pH-dependent fluorescence probe or chemosensors.

RADTRAD: A simplified model for RADionuclide Transport and Removal And Dose estimation

International Nuclear Information System (INIS)

Humphreys, S.L.; Miller, L.A.; Monroe, D.K.; Heames, T.J.

1998-04-01

This report documents the RADTRAD computer code developed for the U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Reactor Regulation (NRR) to estimate transport and removal of radionuclides and dose at selected receptors. The document includes a users' guide to the code, a description of the technical basis for the code, the quality assurance and code acceptance testing documentation, and a programmers' guide. The RADTRAD code can be used to estimate the containment release using either the NRC TID-14844 or NUREG-1465 source terms and assumptions, or a user-specified table. In addition, the code can account for a reduction in the quantity of radioactive material due to containment sprays, natural deposition, filters, and other natural and engineered safety features. The RADTRAD code uses a combination of tables and/or numerical models of source term reduction phenomena to determine the time-dependent dose at user-specified locations for a given accident scenario. The code system also provides the inventory, decay chain, and dose conversion factor tables needed for the dose calculation. The RADTRAD code can be used to assess occupational radiation exposures, typically in the control room; to estimate site boundary doses; and to estimate dose attenuation due to modification of a facility or accident sequence

Removal of radionuclides from radioactive effluents of Purex origin using biomass banana pith as sorbant

International Nuclear Information System (INIS)

Ramanujam, A.; Dhami, P.S.; Kannan, R.; Das, S.K.; Naik, P.W.; Gopalakrishnan, V.; Kansra, V.P.; Balu, K.

1998-06-01

Investigations have been carried out on the applicability of dried banana pith (inner stem) for the sorption of various radionuclides viz. U, Pu, 241 Am, 144 Ce, 147 Pm, 152+154 Eu and 137 Cs which are generally present at trace level in Purex process waste effluents. The sorption of trivalent radionuclides as well as tetravalent plutonium was found to be high at pH 2, whereas sorption of uranium was found to be maximum at pH 6. Cesium was not found to be sorbed. 241 Am sorption was investigated in detail as a representative element of trivalent actinides and fission products to study the general trend. Though its sorption was kinetically slow, near-quantitative sorption was observed on prolonged contact. 241 Am sorption was studied in presence of NaNO 3 (up to 1 M) and Nd(III) up to 500 mg/l. Whereas no significant change in distribution ratios (D) was observed in the presence of NaNO 3 , it increased with neodymium concentration in the range tested. This indicates the effectiveness of the biomass as sorbent even in presence of sodium salts. Sorbed metal ions could be recovered by leaching with 2 M nitric acid. The dried biomass samples prepared from different sources were found to be stable for months and gave similar results on testing. The biomass was tested for its applicability for sorbing radionuclides present in Purex evaporator condensate and diluted high level waste solution on once through basis. The sorption capacity of banana pith for trivalent actinide-lanthanide is in the range of 60 mg/g banana pith. The results indicate that the biomass can be used effectively for the treatment of Purex Waste effluents for the removal of strontium, tri- and tetravalent actinides and fission products. The biomass was also tested for the sorption of toxic metal ions viz. Sr, Hg, Pb, Cr, Cd, and As from a nitrate solution at pH 2 and 4. D values followed the order Hg>Sr>Cd>Pb at pH 2, with Cr and As showing no uptake. These results indicate the potential of this

RIVER-RAD, Radionuclide Transport in Surface Waters

International Nuclear Information System (INIS)

1996-01-01

1 - Description of program or function: RIVER-RAD assesses the potential fate of radionuclides released to rivers. The model is simplified in nature and is intended to provide guidance in determining the potential importance of the surface water pathway, relevant transport mechanisms, and key radionuclides in estimating radiological dose to man. 2 - Method of solution: A compartmental linear transfer model is used in RIVER-RAD. The river system model in the code is divided into reaches (compartments) of equal size, each with a sediment compartment below it. The movement of radionuclides is represented by a series of transfers between the reaches, and between the water and sediment compartments of each reach. Within each reach (for both the water and sediment compartments), the radionuclides are assumed to be uniformly mixed. Upward volatilization is allowed from the water compartment, and the transfer of radionuclides between the reaches is determined by the flow rate of the river. Settling and resuspension velocities determine the transfer of absorbed radionuclides between the water and sediment compartments. Radioactive decay and decay-product buildup are incorporated into all transport calculations for all radionuclide chains specified by the user. Each nuclide may have unique input and removal rates. Volatilization and radiological decay are considered as linear rate constants in the model. 3 - Restrictions on the complexity of the problem: None noted

Characterization of the europium tetracycline complex as a biomarker for atherosclerosis

Science.gov (United States)

Courrol, Lilia C.; da Silva, Mônica N.; Sicchieri, Leticia B.

2016-04-01

Atherosclerosis is a narrowing of the arteries caused by an increase of atheromatous plaque: material formed by macrophage cells containing cholesterol and fatty acids, calcium and a variable amount of fibrous connective tissue. The elation between vulnerable plaques and cardiovascular events can be determined using plaque biomarkers. In this work, atherosclerotic plaques stained with different molar ratios of europium, in a potential plaque biomarker, europium tetracycline complex, were studied by fluorescence microscopy. The tetracycline antibiotic used was chlortetracycline. The growth of atherosclerotic plaque was followed during 60 days in New Zealand rabbits divided in two groups: an experimental group (EG), with nine animals and a control group (CG) with three animals. The animals in the EG received a diet with 1% of cholesterol and the animals of GC received a normal diet. The aortic arch of the animals with 60 days were cut in the vertical plane in 6 μm thick slices, which were mounted on glass slides and stained with hematoxylin an eosin and europium chlortetracycline complex (EuCTc). The fluorescence images were obtained exciting the EuCTc absorption band with a filter cube D (BP 355 - 425) and the emission was collected with a LP 470 suppression filter. Light intensity, detector gain and acquisition time were fixed for comparisons. The 20× magnified images were collected with 12 bit (or 4096 gray tones) resolution. The mean value of gray scale for each molar ratio of EuCTc was different, indicating that the complex interacts with the components of atherosclerotic plaque and the best molar ratio was 1.5 EuCTc. These results indicate the potential use of the EuCTc biomarker for atherosclerotic plaque characterization.

Study on Europium-Doped Hydroxyapatite Nanoparticles by Fourier Transform Infrared Spectroscopy and Their Antimicrobial Properties

Directory of Open Access Journals (Sweden)

Simona-Liliana Iconaru

2013-01-01

Full Text Available Fourier transform infrared spectroscopy (FT-IR analysis was conducted on europium-doped hydroxyapatite, Ca10-xEux(PO46(OH2 nanocrystalline powders (Eu:HAp with 0≤xEu≤0.2. Antimicrobial studies were also performed for the first time on Eu:HAp. The antimicrobial properties of Eu:HAp nanoparticles with 0≤xEu≤0.2 on Gram-negative (E. coli ATCC 25922, Pseudomonas aeruginosa 1397 and Gram-positive (Staphylococcus aureus 0364, Enterococcus faecalis ATCC 29212 bacteria systems and a species of fungus (Candida albicans ATCC 10231 were reported. Our study demonstrates that the antimicrobial activity of Eu:HAp nanoparticles is dependent on the europium concentration.

Europium determination in oxide and oxysulfide luminophors and their wastes by the method of direct and derivative spectrophotometry

International Nuclear Information System (INIS)

Mishchenko, V.T.; Aleksandrova, N.N.

1989-01-01

Spectrophotometric methods for europium determination in luminophors are proposed. Application of standard and derivative spectrophotometry allows one to determine europium in oxide and oxysulfide luminophors, their wastes and raffinates produced during waste reprocessing quite accurately and reliably. When determining Eu 2 O 3 (Eu 2 O 2 S) mass shares within 4-8 % limits absolute deviation from the mean result makes up to more than ± 0.2 %, relative standard deviation does not exceed 0.02

Stability constants of the Europium complexes with the chloride ions

International Nuclear Information System (INIS)

Jimenez R, M.; Solache R, M.; Rojas H, A.

2000-01-01

The stability constants of lanthanides complexes with chloride ions which were determined at the same ionic force but in different media, are significantly different. It does not exist a systematic study over these stability constants. The purpose of this work is to determine the stability constants of the europium complexes with chloride ions at 303 K, by the solvents extraction method. (Author)

The biotic factors role in radionuclide migration of natural-vegetable complexes

International Nuclear Information System (INIS)

Yakushev, B.I.; Kazej, A.I.; Sak, M.M.; Kuz'mich, O.T.; Golushko, R.M.

1992-01-01

In Byelorussiyn from first months after the Chernobyl' accident investigation are conducting on the radionuclide de dynamics in the soil-plant-soil system. The isotope composition of soil contamination density and specific plants radioactivity are studying, the radionuclide migration dynamic through the soil profile is investigating. The data are shown on considerable reduction of the plants radioactivity (1986-91 years) in connection with the reduction in the soil contamination density with gamma-spectrum radionuclides, accounting for Ce-144, Pr-144, Ru-106, Cs-134 decay; information is done on gamma-spectrum radionuclides of organs in natural pine and meadows system. It is shown, that the radionuclides are actively absorbed by roots in a zone of the highest radionuclide concentration and are delivered into the overground plant parts, then actively are removed into environment in the breathing process. 11 refs.; 4 tabs

Mass spectrometric investigation of fluorated europium β-diketonates

International Nuclear Information System (INIS)

Khomenko, V.S.; Lozinskij, M.O.; Fialkov, Yu.A.; Rasshinina, T.A.; Suboch, V.P.; AN Ukrainskoj SSR, Kiev. Inst. Organicheskoj Khimii)

1983-01-01

Ternary complexes of europium with two organic lidands - fluorated β-diketone and organic base - in the aqueous phase at electron shock are investigated; regroupings that take place in them are established. Mass-spectrometric investigation has shown that complexes with β-diketones, containing in oxygen atom in a fluorated radical, eliminate stable molecules of difluorophosgen, CoF 2 . For the complexes studied under the above conditions the Co molecule elimination is also typical which is accompanied by the formation of ions with a metal-carbon bond

Water purification from radionuclides with using fibroid sorbents

International Nuclear Information System (INIS)

Khaydarov, R. A.; Gapurova, O.U.; Khaydarov, R.R.

2005-01-01

Full text: Purification waste water and drinking water from radionuclides, heavy metal ions, organic contamination is one of the important problems today. For solving this problem we have created three types of fibroid sorbents on the base of Polyester: cationic and anionic exchange and carbonic. Main properties of these sorbents are described in this article. For example characteristics of the sorbents for removing radionuclides Co-60,57, Zn-65, Sr-89,90, Cs-134,137, etc., radionuclides containing organic molecules M-P-32, M-I-131, M-Mo-99+Tc-99m, M-C-14, etc., heavy metal ions Zn, Ni, Cu, Sb, Pb, Cd, Cr, U, etc., organic molecules (pesticides, phenols, dioxin, benzene, toluene, etc.) were investigated. Influence of pH on percent removal, influence of K, Na and another ions concentrations in the liquid on the percent removal, decreasing of the saturation capacity from number of regeneration and another characteristics are described. Static exchange capacity of the cationic sorbents is 1-2 mg-equ/g and anionic - 0.5-1 mg-equ/g. Capacity of the carbonic sorbents for benzene is 100 mg/g. Time of chemical balance setting is 1-2 s. The sorbents are effective in removing the low concentrations of contamination from the water (lower than 100-200 mg/l) and the air (lower than 100 mg/m 3 ). The use of sorbents in drinking water filters and mini-systems is described. The industrial water purification system consists of coagulating unit, sorbent unit and disinfectant unit. The systems are used in atomic power stations, electroplating plants, matches plants, leather and skin treating plants, car-washing stations, etc

Purification of radionuclides for nuclear medicine

International Nuclear Information System (INIS)

Horwitz, E.P.; Bond, A.H.

2002-01-01

Novel systems for the rapid separation of 67 Cu, 90 Y, 188 Re, 212 Bi, 213 Bi, and 223 Ra are described. To achieve the high levels of decontamination required of radionuclides used in radioimmunotherapy, we have utilised combinations of ion exchange (IX) and novel extraction chromatographic (EXC) resins. The objective of each separation system is to remove by many orders of magnitude the parent isotopes and to reduce the concentrations of stable, sometimes adventitious impurities, to low levels. The latter objective is particularly important to achieve a high degree of bonding of radionuclide onto a monoclonal antibody. The purification of 212 Bi (60.6 min half-life) furnishes a good example of the level of purity that we have achieved using tandem combinations of EXC and IX resins. Bismuth-212 was separated from its daughters, 212 Pb, 224 Ra, 228 Th and 232 U at the 50 mCi level. The resultant 212 Bi decayed to background in a few days indicative of high purity. Another example of extraordinary removal of parent nuclide from daughter nuclide and subsequent purification of daughter from stable elements is the preparation of 90 Y. Strontium-90 was removed from 90 Y by > 10 9 . The purified 90 Y uptake by monoclonal antibodies was close to 100%

Dendrimer-coated magnetic particles for radionuclide separation

NARCIS (Netherlands)

Grüttner, Cordula; Böhmer, Volker; Casnati, Alessandro; Dozol, Jean-Francois; Reinhoudt, David; Reinoso garcia, M.M.; Rudershausen, Sandra; Teller, Joachim; Ungaro, Rocco; Verboom, Willem; Wang, Pingshan

2005-01-01

Magnetic particles were synthesised for radionuclide removal from nuclear wastes by magnetic separation. Dendrimers with terminal amino groups attached to the particle surface were used to bind chelating groups for lanthanides and actinides. This led to a 50–400-fold increase of the distribution

Guidebook for the treatment of accidental internal radionuclide contamination of workers

Energy Technology Data Exchange (ETDEWEB)

Bhattacharyya, M H [Argonne National Lab., IL (United States); Breitenstein, B D [Brookhaven National Lab., Upton, NY (United States); Metivier, H [CEA Centre d' Etudes Nucleaires de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire; Muggenburg, B A [ITRI, Albuquerque, NM (United States); Stradling, G N [National Radiological Protection Board, Chilton (United Kingdom); Volf, V [Kernforschungszentrum Karlsruhe GmbH (Germany)

1992-01-01

This book is intended as a guide to the treatment of victims following an accident in which radionuclides have entered the body. It is a practical guide based on a review of current treatments to remove radionuclides from the body and prevent radiation-induced disease. This book should be used by occupational physicians, emergency room physicians, health physicists, paramedics and emergency personnel, nurses, and other related medical personnel. It is intended to provide an overview of the subject and practical information for treating and caring for persons exposed to radionuclides. (author).

External accumulation of radionuclide in hepatic hydrothorax

International Nuclear Information System (INIS)

Albin, R.J.; Johnston, G.S.

1989-01-01

Hepatic hydrothorax is a complication in approximately 5% of patients with cirrhosis. Ascites is almost always present and helps to suggest the correct diagnosis. However, when ascites is absent, radionuclide imaging has proven to be helpful in establishing that the pleural effusion originated from ascitic fluid. When pleural fluid is rapidly removed, such as by thoracostomy tube drainage, the radioisotope may accumulate outside the thorax and produce a negative scan of the chest. When the radionuclide scan is nondiagnostic and the pleural space is being rapidly drained, the pleural fluid collecting system should always be imaged before rejecting a diagnosis of hepatic hydrothorax

Synthesis and characterization of highly triboluminescent doped europium tetrakis compounds

International Nuclear Information System (INIS)

Fontenot, Ross S.; Hollerman, William A.; Bhat, Kamala N.; Aggarwal, Mohan D.

2012-01-01

One of the most intriguing properties involving crystals is their ability to emit light when fractured. While this property was discovered over 200 years ago, no one has ever been able to come up with a complete theory that can predict the physical principles associated with triboluminescence. However, this has not stopped scientists from coming up with various uses for these materials. One such application is to use these materials as the active element for smart impact sensors that can warn of catastrophic impacts. If these sensors are to become a reality however, the material must emit a bright light when fractured. One of the brightest triboluminescent materials found thus far is europium dibenzoylmethide triethylammonium (EuD 4 TEA). This material was discovered by Hurt in 1966 and is bright enough to be seen in daylight. In 2011, the authors discovered that synthesizing EuD 4 TEA using europium nitrate instead of chloride significantly increased the triboluminescence yield and made the synthesis much easier and more consistent. However, to date, there are few investigations into the effects of dopants on the triboluminescence of EuD 4 TEA. This paper reports the investigation of the effects of various dopants on: (1) The triboluminescent light yield, (2) Crystal size and structure, (3) Synthesis time, and (4) Prompt decay time. Results show that inclusion of dopants during synthesis increases the triboluminescence emission of EuD 4 TEA by 55%, significantly reduces the synthesis time, and controls the decay time. All of these properties can be useful for constructing the first prototype of a customized impact sensor. - Highlights: ► Doped europium dibenzoylmethide triethylammonium (EuD 4 TEA) was synthesized. ► Effects of dopants was studied from EuD 4 TEA during low velocity (<10 m/s) impacts. ► The triboluminescent light yield, decay time, and synthesis time were measured. ► A specially-built drop tower was developed to measure triboluminescence

Time-resolved laser fluorescence spectroscopy of organic ligands by europium: Fluorescence quenching and lifetime properties

Science.gov (United States)

Nouhi, A.; Hajjoul, H.; Redon, R.; Gagné, J. P.; Mounier, S.

2018-03-01

Time-resolved Laser Fluorescence Spectroscopy (TRLFS) has proved its usefulness in the fields of biophysics, life science and geochemistry to characterize the fluorescence probe molecule with its chemical environment. The purpose of this study is to demonstrate the applicability of this powerful technique combined with Steady-State (S-S) measurements. A multi-mode factor analysis, in particular CP/PARAFAC, was used to analyze the interaction between Europium (Eu) and Humic substances (HSs) extracted from Saint Lawrence Estuary in Canada. The Saint Lawrence system is a semi-enclosed water stream with connections to the Atlantic Ocean and is an excellent natural laboratory. CP/PARAFAC applied to fluorescence S-S data allows introspecting ligands-metal interactions and the one-site 1:1 modeling gives information about the stability constants. From the spectral signatures and decay lifetimes data given by TRLFS, one can deduce the fluorescence quenching which modifies the fluorescence and discuss its mechanisms. Results indicated a relatively strong binding ability between europium and humic substances samples (Log K value varies from 3.38 to 5.08 at pH 7.00). Using the Stern-Volmer plot, it has been concluded that static and dynamic quenching takes places in the case of salicylic acid and europium interaction while for HSs interaction only a static quenching is observed.

Production of a tracer packet of heavier rare earth elements

International Nuclear Information System (INIS)

Lahiri, S.; Nayak, D.; Maji, S.

2004-01-01

Production of a tracer packet of heavier rare earth elements containing carrier-free radionuclides of 153,155 Tb, 153,155,157 Dy, 159 Ho, 159,161 Er, 161 Tm produced by medium energy 7 Li and 12 C irradiation on an europium oxide target and the subsequent separation of bulk europium from the carrier-free products is described. (author)

Bioenvironmental aspects of europium and rhodium: a selected bibliography

International Nuclear Information System (INIS)

Fore, C.S.; Carrier, R.F.; Talmage, S.S.; Fielden, J.M.; Daniel, E.W.

1983-09-01

This bibliography of 428 abstracted references represents a summary of the domestic and foreign literature relevant to the biological and environmental aspects of europium and rhodium. The collected data are organized by current NAEG interests - research highlighting inventory and distribution of the radionulcides, ecological studies covering terrestrial and aquatic systems, and biological studies in both man and animals. Studies that focus directly on research conducted at specific sites (e.g., the Nevada Test Site) are emphasized throughout the bibliography

Electron-induced desorption of europium atoms from oxidized tungsten surface: concentration dependence of low-energy peak

CERN Document Server

Davydov, S Y

2002-01-01

One discusses nature of electron induced desorption of Eu sup 0 europium atoms under E sub e irradiating electron low-energies (approx 30 eV) and peculiarities of yield dependence of Eu sup 0 atoms on their concentration at oxidized tungsten surface. Primary act of vacancy origination in europium adatom inner 5p-shell turned to be the determining stage. Evaluations have shown that just the first of two possible scenarios of ionization (electron intra-atomic to Eu adatom external quasi-level or realise of knocked out electron into vacuum) leads to Eu sup 0 desorption. One determined concentration threshold for yield of Eu sup 0 atoms

Radionuclides incorporation in activated natural nanotubes

International Nuclear Information System (INIS)

Silva, Jose Parra

2016-01-01

Natural palygorskite nanotubes show suitable physical and chemical properties and characteristics to be use as potential nanosorbent and immobilization matrix for the concentration and solidification of radionuclides present in nuclear wastes. In the development process of materials with sorption properties for the incorporation and subsequent immobilization of radionuclides, the most important steps are related with the generation of active sites simultaneously to the increase of the specific surface area and suitable heat treatment to producing the structural folding. This study evaluated the determining parameters and conditions for the activation process of the natural palygorskite nanotubes aiming at the sorption of radionuclides in the nanotubes structure and subsequent evaluation of the parameters involve in the structural folding by heat treatments. The optimized results about the maximum sorption capacity of nickel in activated natural nanotubes show that these structures are apt and suitable for incorporation of radionuclides similar to nickel. By this study is verified that the optimization of the acid activation process is fundamental to improve the sorption capacities for specifics radionuclides by activated natural nanotubes. Acid activation condition optimized maintaining structural integrity was able to remove around 33.3 wt.% of magnesium cations, equivalent to 6.30·10 -4 g·mol -1 , increasing in 42.8% the specific surface area and incorporating the same molar concentration of nickel present in the liquid radioactive waste at 80 min. (author)

Radionuclide transport and retardation in tuff

International Nuclear Information System (INIS)

Vine, E.N.; Bayhurst, B.P.; Daniels, W.R.; DeVilliers, S.J.; Erdal, B.R.; Lawrence, F.O.; Wolfsberg, K.

1980-01-01

Batch measurements provide an understanding of which experimental variables are important. For example, sorption ratios vary little with particle size (and surface area); however, groundwater composition and rock composition are quite important. A general correlation has been identified between mineralogy (major phases) and degree of sorption for strontium, cesium, and barium. Although these are approximate, a more detailed analysis may be possible as more samples are studied and the data base increased. Data from crushed tuff columns indicate that, except in simple cases where sorption coefficients are relatively low, and ion-exchange equilibria not only exist but are the dominant mechanism for removal of radioisotopes from solution, the simple relation between the sorption ratio R/sub d/ (or K/sub d/) and the relative velocity of radionuclides with respect to groundwater velocity may be insufficient to permit accurate modeling of the retardation of radionuclides. Additional work on whole core columns and larger blocks of intact material is required to better understand radionuclide sorption and transport through rock

Sorption of Europium in zirconium silicate

International Nuclear Information System (INIS)

Garcia R, G.

2004-01-01

Some minerals have the property of sipping radioactive metals in solution, that it takes advantage to manufacture contention barriers that are placed in the repositories of nuclear wastes. The more recent investigations are focused in the development of new technologies guided to the sorption of alpha emissors on minerals which avoid their dispersion in the environment. In an effort to contribute to the understanding of this type of properties, some studies of sorption of Europium III are presented like homologous of the americium, on the surface of zirconium silicate (ZrSiO 4 ). In this work the results of sorption experiences are presented as well as the interpretation of the phenomena of the formation of species in the surface of the zirconium silicate. (Author)

Metal plasmon enhanced europium complex luminescence

International Nuclear Information System (INIS)

Liu Feng; Aldea, Gabriela; Nunzi, Jean-Michel

2010-01-01

The plasmon enhanced luminescence of a rare-earth complex Tris(6, 6, 7, 7, 8, 8, 8-heptafluoro-2, 2-dimethyl-3, 5-octanedionato) europium (Eu(fod) 3 ) was investigated. A polyvinyl alcohol (PVA) thin film was successfully adopted as a spacer to separate the Eu complex from the silver island film (SIF), and five-fold enhancement of the radiative decay rate of the Eu complex on SIF was demonstrated based on the luminescence intensity and lifetime measurement. Investigation of the distance dependent luminescence indicates that 7 nm is an optimal distance for SIF enhanced Eu luminescence. Plasmon enhanced rare-earth luminescence based on an organic film spacer would find potential applications in plasmon enhanced organic light emitting diode (OLED) devices.

Determination of the hydrolysis constants of Europium (III), in ion strength media 4, 5 and 6 M NaClO4 at 303 K

International Nuclear Information System (INIS)

Alvarado B, A.; Jimenez R, M.; Solache R, M.

1999-01-01

This work was made with the purpose to complete information about the hydrolysis constants of Europium (III) in high ion strength media. So it was determined at a ion forces media 4, 5 and 6 M of sodium perchlorate at 303 K. The method used was the potentiometric with the aid of the Super quad computer program. In high ion strength media, the measurements of p H do not correspond directly to negative logarithm of the concentration of hydrogen ions, by this it is necessary to calibrate the electrode in these conditions. The Europium was hydrolized at pC H values greater 6 in all cases. The potentiometric method used under the described experimental conditions is adequate to determine the hydrolysis constants of Europium (III). According to the results and diagrams of chemical species of Europium obtained we can conclude that the hydrolysis constants, differ by its distribution but not in its identity. (Author)

Improved efficiency of organic light-emitting diodes based on a europium complex by fluorescent dye

Energy Technology Data Exchange (ETDEWEB)

You Han [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Fang Junfeng [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Gao Jia [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Ma Dongge [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China)]. E-mail: mdg1014@ciac.jl.cn

2007-01-15

Improved efficiency of organic light-emitting diodes (OLEDs) based on europium complexes have been realized by using a fluorescent dye 4-(dicyanomethylene)-2-t-butyl-6 (1,1,7,7-tetramethyljulolidyl-9-enyl))-4H-pyran (DCJTB) doping .The luminous efficiency of the devices with a fluorescent dye in the emissive layer was found to improve two times of that in devices without fluorescent dye. The devices showed pure red light, which is the characteristic emission of trivalent europium ion with a full-width at half-maximum of 3 nm.The maximum brightness and luminous efficiency reached 1200 cd/m{sup 2} at 23 V and 7.3 cd/A (2.0 lm/w), respectively, at a current density of 0.35 mA/cm{sup 2}.

Determination of the first hydrolysis constant of Europium (III) in 3 M of ionic strength

International Nuclear Information System (INIS)

Ramirez B, M.E.

1994-01-01

The first hydrolysis constant of Eu 3+ has been determined at 303 K and 3 M (NaCl) ionic strength. A solvent extraction method was used, the extractant was dibenzoylmethane in benzene and di glycolate anion in the aqueous phase provided competitive complexation. The tracer solution was 152m1 Eu (III) in water. The radioactive solution of europium was obtained by neutron irradiation of europium nitrate solutions at pH 3.0, in a TRIGA Mark III nuclear reactor at a neutron flux of 1 x 10 13 cm -2 s -1 . The half life of the produced isotope, 152m1 Eu (9.3 h), was verified by means of a Ge H detector and no interfering radiations were observed in the spectra. (Author)

Preparation, characterization and application of superparamagnetic iron oxide nanoparticles modified with natural polymers for removal of {sup 60}Co-radionuclides from aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Sharaf El-Deen, Gehan E. [Atomic Energy Authority, Cairo (Egypt). Radioactive Waste Management Dept.; Imam, Neama G. [Atomic Energy Authority, Cairo (Egypt). Experimental Physics Dept.; Elettra, Sincrotrone, Trieste (Italy); Ayoub, Refaat R. [Atomic Energy Authority, Cairo (Egypt). Nuclear Chemistry Dept.

2017-04-01

Superparamagnetic iron oxide nanoparticles (IO-MNPs) coated with natural polymers, starch (IO-S MNPs) and dextrin (IO-D MNPs), were synthesized by modified co-precipitation method. IO and hybrid-IO-MNPs were characterized by XRD, SEM, HRTEM, FT-IR spectroscopy, vibrating sample magnetometer (VSM) and zeta potential (ZP). IO-S MNPs and IO-D MNPs have IO core-shell structure with core of 10.8 nm and 13.8 nm and shell of 7.5 nm and 5.9 nm, respectively. The efficiency of the hybrid IO-MNPs for sorption of {sup 60}Co(II)-radionuclides from aqueous solution was investigated under varying experimental conditions. Kinetic data were described well by pseudo-second-order mode, sorption isotherms were fitted quite with Freundlich model with maximum adsorption capacity 36.89 (mmol.g{sup -1})/(L.mmol{sup -1}){sup n} for IO-S MNPs and 24.9 (mmol.g{sup -1})/(L.mmol{sup -1}){sup n} for IO-D MNPs. Sorption of {sup 60}Co-radionuclides by IO-S MNPs was suppressed with salinity and most of the adsorbed {sup 60}Co onto IO-S MNPs could be remove with 0.1 M HCl solution. IO-S MNPs exhibits superparamagnetic properties, easier separation according to higher saturation magnetization (47 emu/g) and better adsorption for {sup 60}CO-radionuclides than IO-D MNPs.

Accumulation of nuclear fission products by vegetable crops and their removal during processing

International Nuclear Information System (INIS)

Weaver, C.M.

1978-01-01

The accumulation and turn over of 90 Sr and 137 Cs throughout the growth cycle of a vegetable crop was studied as well as the removal of these radionuclides in several vegetables by washing, blanching, freezing, canning, and pickling procedures. The results indicated that radiocontamination of vegetable crops with 137 Cs would result in greatest internal concentrations if exposure occurred early in the growth cycle of the plant, whereas, the greatest contamination by 90 Sr would occur from exposure during the middle of the growing period. Pulse labelling experiments were employed to examine turn over of radionuclides in kale. No net efflux of radionuclides from plants following exposure to either radionuclide was observed. Of the processing treatments employed on several types of vegetables, a combination of pickling and canning of cucumbers resulted in the greatest decontamination - 94% for 137 Cs and 65% for 90 Sr. Canning was highly effective in reducing radionuclide concentrations in beans and kale. However, freezing significantly reduced the radionuclide content of only 137 Cs in kale. Preparatory procedures prior to processing did not significantly reduce radionuclide levels except for 137 Cs in beans. The combination of washing, blanching, and canning sweet potatoes exposed to radionuclides resulted in the removal of 1.4% 137 Cs and 26.5% 90 Sr relative to unprocessed controls. The blanching process resulted in a transfer of radioactivity from the peel to the core, indicating that skins of contaminated potatoes should be removed prior to thermal treatment

Studies on effect of europium concentration on the photoemission of laser ablated Y2O3:Eu based nano-phosphors

International Nuclear Information System (INIS)

Nissamudeen, K.M.; Krishnan, Renju R.; Rajan, Geo; Gopchandran, K.G.

2007-01-01

Full text: Phosphors are essential materials in display applications. Oxide-based phosphors are likely to emerge as the potential choice for the FED red phosphor. Among those oxide-based phosphors, there has been significant research interest in the development of Y 2 O 3 :Eu thin films as one of the most promising oxide based red phosphor systems. Yttrium oxide mixed with europium exhibit strong UV and cathode-ray-excited luminescence that are useful in lamp and display applications. Dielectric Y 2 O 3 film has recently attracted much attention for its potential application as an electric insulation layer in electroluminescent devices and high-density dynamic random access memory gate dielectrics because of its high band gap (5.8 eV) and large dielectric constant (14 to 18). Another important application of Y 2 O 3 has been in luminescent displays as a host material for rare-earth ions, specifically europium, in order to get emission of red light. In the present study thin films were deposited under a vacuum of 10 -6 mbar on fused amorphous quartz substrates using a Q-switched Nd: YAG laser, 532 nm, pulse width 9 n sec, and repetition frequency of 10 Hz, with sintered Y 2 O 3 pellets having different europium concentration as target material. Attempts were made to understand the effect of europium concentration and annealing process on the photoemission properties of the films. A europium concentration of 8 wt% and an annealing temperature of 1173 K were found to be optimum conditions for maximum photoemission. The dependence of structure and morphology of the films on the photoemission intensity are described with XRD patterns and images obtained from AFM and SEM studies

Test of zircon materials for sorption of europium

International Nuclear Information System (INIS)

Ordonez R, E.; Fernandez V, S.M.; Garcia R, G.

2003-01-01

In previous works it has already been made notice that some phosphates have the property of sipping radioactive metals in solution, what takes advantage to fabricate reactive barriers that are placed in the repositories of nuclear wastes. In our laboratory it has been obtained to the zirconium silicate (ZrSiO 4 ) and the alpha zirconium hydrogen phosphate (Zr(HPO 4 ) 2H 2 0) starting from sea sand in an easy and economic way. With the interest of knowing if these compounds can be used in contention barriers the evaluation of their surface properties it is made and of europium sorption. (Author)

Electronic structure and superconductivity of europium

International Nuclear Information System (INIS)

Nixon, Lane W.; Papaconstantopoulos, D.A.

2010-01-01

We have calculated the electronic structure of Eu for the bcc, hcp, and fcc crystal structures for volumes near equilibrium up to a calculated 90 GPa pressure using the augmented-plane-wave method in the local-density approximation. The frozen-core approximation was used with a semi-empirical shift of the f-states energies in the radial Schroedinger equation to move the occupied 4f valence states below the Γ 1 energy and into the core. This shift of the highly localized f-states yields the correct europium phase ordering with lattice parameters and bulk moduli in good agreement with experimental data. The calculated superconductivity properties under pressure for the bcc and hcp structures are also found to agree with and follow a T c trend similar to recent measurement by Debessai et al.

Water Distribution and Removal Model

International Nuclear Information System (INIS)

Y. Deng; N. Chipman; E.L. Hardin

2005-01-01

The design of the Yucca Mountain high level radioactive waste repository depends on the performance of the engineered barrier system (EBS). To support the total system performance assessment (TSPA), the Engineered Barrier System Degradation, Flow, and Transport Process Model Report (EBS PMR) is developed to describe the thermal, mechanical, chemical, hydrological, biological, and radionuclide transport processes within the emplacement drifts, which includes the following major analysis/model reports (AMRs): (1) EBS Water Distribution and Removal (WD and R) Model; (2) EBS Physical and Chemical Environment (P and CE) Model; (3) EBS Radionuclide Transport (EBS RNT) Model; and (4) EBS Multiscale Thermohydrologic (TH) Model. Technical information, including data, analyses, models, software, and supporting documents will be provided to defend the applicability of these models for their intended purpose of evaluating the postclosure performance of the Yucca Mountain repository system. The WD and R model ARM is important to the site recommendation. Water distribution and removal represents one component of the overall EBS. Under some conditions, liquid water will seep into emplacement drifts through fractures in the host rock and move generally downward, potentially contacting waste packages. After waste packages are breached by corrosion, some of this seepage water will contact the waste, dissolve or suspend radionuclides, and ultimately carry radionuclides through the EBS to the near-field host rock. Lateral diversion of liquid water within the drift will occur at the inner drift surface, and more significantly from the operation of engineered structures such as drip shields and the outer surface of waste packages. If most of the seepage flux can be diverted laterally and removed from the drifts before contacting the wastes, the release of radionuclides from the EBS can be controlled, resulting in a proportional reduction in dose release at the accessible environment

Water Distribution and Removal Model

Energy Technology Data Exchange (ETDEWEB)

Y. Deng; N. Chipman; E.L. Hardin

2005-08-26

The design of the Yucca Mountain high level radioactive waste repository depends on the performance of the engineered barrier system (EBS). To support the total system performance assessment (TSPA), the Engineered Barrier System Degradation, Flow, and Transport Process Model Report (EBS PMR) is developed to describe the thermal, mechanical, chemical, hydrological, biological, and radionuclide transport processes within the emplacement drifts, which includes the following major analysis/model reports (AMRs): (1) EBS Water Distribution and Removal (WD&R) Model; (2) EBS Physical and Chemical Environment (P&CE) Model; (3) EBS Radionuclide Transport (EBS RNT) Model; and (4) EBS Multiscale Thermohydrologic (TH) Model. Technical information, including data, analyses, models, software, and supporting documents will be provided to defend the applicability of these models for their intended purpose of evaluating the postclosure performance of the Yucca Mountain repository system. The WD&R model ARM is important to the site recommendation. Water distribution and removal represents one component of the overall EBS. Under some conditions, liquid water will seep into emplacement drifts through fractures in the host rock and move generally downward, potentially contacting waste packages. After waste packages are breached by corrosion, some of this seepage water will contact the waste, dissolve or suspend radionuclides, and ultimately carry radionuclides through the EBS to the near-field host rock. Lateral diversion of liquid water within the drift will occur at the inner drift surface, and more significantly from the operation of engineered structures such as drip shields and the outer surface of waste packages. If most of the seepage flux can be diverted laterally and removed from the drifts before contacting the wastes, the release of radionuclides from the EBS can be controlled, resulting in a proportional reduction in dose release at the accessible environment. The purposes

Mass spectrometric investigation of fluorated europium. beta. -diketonates. [Electrons

Energy Technology Data Exchange (ETDEWEB)

Khomenko, V.S.; Lozinskij, M.O.; Fialkov, Yu.A.; Rasshinina, T.A.; Suboch, V.P. (AN Belorusskoj SSR, Minsk. Inst. Fiziki; AN Ukrainskoj SSR, Kiev. Inst. Organicheskoj Khimii)

Ternary complexes of europium with two organic ligands - fluorated ..beta..-diketone and organic base - in the aqueous phase at electron shock are investigated; regroupings that take place in them are established. Mass-spectrometric investigation has shown that complexes with ..beta..-diketones, containing in oxygen atom in a fluorated radical, eliminate stable molecules of difluorophosgen, CoF/sub 2/. For the complexes studied under the above conditions the Co molecule elimination is also typical which is accompanied by the formation of ions with a metal-carbon bond.

The principal radionuclides in high level radioactive waste management

International Nuclear Information System (INIS)

Mulyanto

1998-01-01

The principal radionuclides in high level radioactive waste management. The selection of the principal radionuclides in the high level waste (HLW) management was developed in order to improve the disposal scenario of HLW. In this study the unified criteria for selection of the principal radionuclides were proposed as; (1) the value of hazard index estimated by annual limit of intake (ALI) for long-term tendency,(2) the relative dose factor related to adsorbed migration rate transferred by ground water, and (3) heat generation in the repository. From this study it can be concluded that the principal radionuclides in the HLW management were minor actinide (MA=Np, Am, Cm, etc), Tc, I, Cs and Sr, based on the unified basic criteria introduced in this study. The remaining short-lived fission product (SLFPs), after the selected nuclides are removed, should be immobilized and solidified in a glass matrix. Potential risk due to the remaining SLFPs can be lower than that of uranium ore after about 300 year. (author)

Task summary: Hot demonstration of proposed commercial nuclide removal technology

International Nuclear Information System (INIS)

Lee, D.D.; Travis, J.R.

1995-11-01

Radionuclides represent only a small fraction of the components in millions of gallons of storage tank supernatant at various sites, including Oak Ridge, Hanford, Savannah River, and Idaho. Most of the radioactivity is contributed by cesium, strontium, and technetium along with high concentrations of sodium and potassium salts. The purpose of this task is to test and select sorbents and commercial removal technologies supplied by ESP for removing and concentrating the radionuclides, thereby reducing the volume of waste to be stored or disposed

Hydrotalcite formation facilitates effective contaminant and radionuclide removal from acidic uranium mine barren lixiviant

International Nuclear Information System (INIS)

Douglas, Grant; Shackleton, Mark; Woods, Peter

2014-01-01

Highlights: • Remediation of barren lixiviant using hydrotalcite precipitation. • High U and rare earth element concentration factor. • Hydrotalcite may be further modified for long-term disposal. • Potential application to U and other commodities. - Abstract: An assessment of hydrotalcite (HT) formation as a method to neutralise acidity and remove trace elements was undertaken using barren lixiviant from Heathgate Resources’ Beverley North in situ recovery (ISR) U mine in South Australia. This study demonstrated proof of concept in terms of the neutralisation of acidity and concomitant removal of a range of trace elements and U–Th series radionuclides from the barren lixiviant using MgCl 2 as a supplementary Mg source to optimise Mg:Al mol ratios and NaOH as the neutralising agent. Hydrotalcite was the predominant mineral formed during neutralisation, hosting a range of elements including substantial U (∼0.2%) and rare earth elements (REE ∼0.1%). High U and REE recovery (∼99%) from barren lixiviant after HT precipitation indicates a potential to both remediate barren lixiviant and to offset remediation costs. Alternatively, HT precipitates formed during barren lixiviant neutralisation may be further stabilised via calcination, silicification or a combination thereof forming minerals potentially amenable for inclusion in a long-term waste repository at the cessation of ISR mining. Importantly, the composition of the neutralised barren lixiviant produced via HT precipitation is similar to that of existing groundwater allowing for the possibility of direct aquifer re-injection after remediation. A potential exists to apply this HT-based remediation technology to conventional or ISR U mines (or mines exploiting other commodities) and allows for the prospect of a fully integrated ISR mining, processing and lixiviant remediation strategy consistent with stringent environmental and mine closure standards

Natural and Synthetic Barriers to Immobilize Radionuclides

International Nuclear Information System (INIS)

Um, W.

2011-01-01

The experiments of weathering of glass waste form and the reacted sediments with simulated glass leachates show that radionuclide sequestration can be significantly enhanced by promoting the formation of secondary precipitates. In addition, synthetic phosphate-bearing nanoporous material exhibits high stability at temperature and has a very high K d value for U(VI) removal. Both natural and synthetic barrier materials can be used as additional efficient adsorbents for retarding transport of radionuclides for various contaminated waste streams and waste forms present at U. S. Department of Energy clean-up sites and the proposed geologic radioactive waste disposal facility. In the radioactive waste repository facility, natural or synthetic materials are planned to be used as a barrier material to immobilize and retard radionuclide release. The getter material can be used to selectively scavenge the radionuclide of interest from a liquid waste stream and subsequently incorporate the loaded getters in a cementitious or various monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides form monolithic waste forms by being emplaced as a backfill barrier material around the wastes or waste form to minimize the potential around the wastes or waste form to minimize the potential hazard of leached radioactive wastes. The barrier material should be highly efficient to sequester radionuclides and possess physical and chemical stability for long-term exposure to severe weathering conditions. Because potential leaching of radionuclides depends on various environmental and weathering conditions of the near-field repository, the barrier materials must be durable and not disintegrate under a range of moisture, temperature, pressure, radiation, Eh, ph. and

Decontamination of radionuclides in food

Energy Technology Data Exchange (ETDEWEB)

Ohmomo, Yoichiro [Institute for Environmental Sciences, Aomori (Japan)

1994-03-01

The release of radionuclides arising from the Chernobyle accident led to widespread contamination of the northern hemisphere through fallout. This accident provided again an opportunity to investigate how and to what extent the radionuclides contamination in crops and animal derived foods could be reduced. The following topics are included in this paper. (1) How to reduce the transfer of radiostrontium and/or cesium from soil to crops: A pH increase of soil is effective for reducing their plant uptake. (2) How to reduce the transfer of radiocesium to animal derived foods: Ammonium-ferric-cyanoferrate (AFCF) should be the most effective compound for radiocesium excretion in the feces. Experiments with lactating cows and/or poultry gave extremely good results with respect to low radiocesium concentrations in milk, meat and eggs. (3) Removal coefficients of radiostrontium, cesium and iodine from contaminated leaf vegetables and cereals during food processing and culinary preparation: Though different by species, more than 80% of cesium and about 50% of strontium and iodine can be removed during culinary preparation of washing and boiling. (4) Simultaneous decontamination of radiocesium and iodine from drinking water and liquid milk: Metal ferrocyanide-anion exchange resin, specifically Fe ferrocyanide one, was successfully used for a rapid and simple decontamination of radiocesium and iodine in the liquid samples arising from the Chernobyle accident. (5) Removal of radiocesium from meat: The meat structurally contaminated with radiocesium is easily and very successfully decontaminated by pickling in NaCl solution and the decontamination is much speeded up by freezing meat before pickling. (author).

Decontamination of radionuclides in food

International Nuclear Information System (INIS)

Ohmomo, Yoichiro

1994-01-01

The release of radionuclides arising from the Chernobyle accident led to widespread contamination of the northern hemisphere through fallout. This accident provided again an opportunity to investigate how and to what extent the radionuclides contamination in crops and animal derived foods could be reduced. The following topics are included in this paper. (1) How to reduce the transfer of radiostrontium and/or cesium from soil to crops: A pH increase of soil is effective for reducing their plant uptake. (2) How to reduce the transfer of radiocesium to animal derived foods: Ammonium-ferric-cyanoferrate (AFCF) should be the most effective compound for radiocesium excretion in the feces. Experiments with lactating cows and/or poultry gave extremely good results with respect to low radiocesium concentrations in milk, meat and eggs. (3) Removal coefficients of radiostrontium, cesium and iodine from contaminated leaf vegetables and cereals during food processing and culinary preparation: Though different by species, more than 80% of cesium and about 50% of strontium and iodine can be removed during culinary preparation of washing and boiling. (4) Simultaneous decontamination of radiocesium and iodine from drinking water and liquid milk: Metal ferrocyanide-anion exchange resin, specifically Fe ferrocyanide one, was successfully used for a rapid and simple decontamination of radiocesium and iodine in the liquid samples arising from the Chernobyle accident. (5) Removal of radiocesium from meat: The meat structurally contaminated with radiocesium is easily and very successfully decontaminated by pickling in NaCl solution and the decontamination is much speeded up by freezing meat before pickling. (author)

Alpha Emitting Radionuclides and Radiopharmaceuticals for Therapy

International Nuclear Information System (INIS)

Chérel, Michel; Barbet, Jacques

2013-01-01

Today, cancer treatments mainly rely on surgery or external beam radiation to remove or destroy bulky tumors. Chemotherapy is given when tumours cannot be removed or when dissemination is suspected. However, these approaches cannot permanently treat all cancers and relapse occurs in up to 50% of the patients’ population. Radioimmunotherapy (RIT) and peptide receptor radionuclide therapy (PRRT) are effective against some disseminated and metastatic diseases, although they are rarely curative. Most preclinical and clinical developments in this field have involved electron-emitting radionuclides, particularly iodine-131, yttrium-90 and lutetium-177. The large range of the electrons emitted by these radionuclides reduces their efficacy against very small tumour cell clusters or isolated tumour cells present in residual disease and in many haematological tumours (leukaemia, myeloma). The range of alpha particles in biological tissues is very short, less than 0.1 mm, which makes alpha emitters theoretically ideal for treatment of such isolated tumour cells or micro-clusters of malignant cells. Thus, over the last decade, a growing interest for the use of alpha-emitting radionuclides has emerged. Research on targeted alpha therapy (TAT) began years ago in Nantes through cooperation between Subatech, a nuclear physics laboratory, CRCNA, a cancer research centre with a nuclear oncology team and ITU (Karlsruhe, Germany). CD138 was demonstrated as a potential target antigen for Multiple Myeloma, which is a target of huge clinical interest particularly suited for TAT because of the disseminated nature of the disease consisting primarily of isolated cells and small clusters of tumour cells mainly localized in the bone marrow. Thus anti-CD138 antibodies were labelled with bismuth-213 from actinium-225/bismuth-213 generators provided by ITU and used to target multiple myeloma cells. In vitro studies showed cell cycle arrest, synergism with chemotherapy and very little induction

Behaviour of Chernobyl fallout radionuclides deposited on peat and urban surfaces in Finland

International Nuclear Information System (INIS)

Reponen, A.

1992-10-01

In the thesis the impact of the Chernobyl nuclear reactor accident on Finland was studied in three aspects: (1) the areal distribution of Chernobyl fallout in Finland was determined by measuring peat samples, (2) the behaviour of fallout radionuclides was investigated in the combustion of peat in power plants, and (3) the removal rates of fallout radionuclides on urban surfaces were resolved

ULTRAVIOLET TRANSITIONS IN EUROPIUM STUDIED WITH A FREQUENCY-DOUBLED CW RING DYE-LASER

NARCIS (Netherlands)

Eliel, E.R.; Hogervorst, W.; van Leeuwen, K.A.H.; Post, B.H.

1981-01-01

High resolution laser spectroscopy has been applied to the study of three ultraviolet transitions in Europium at λ = 294.8, 295.1 and 295.8 nm. The tunable narrowband UV has been generated by intracavity frequency doubling in a cw ring dye laser using a temperate tuned, Brewster angled ADA crystal.

Detection of Molecular Chirality by Induced Resonance Raman Optical Activity in Europium Complexes

Czech Academy of Sciences Publication Activity Database

Yamamoto, Shigeki; Bouř, Petr

2012-01-01

Roč. 51, č. 44 (2012), s. 11058-11061 ISSN 1433-7851 R&D Projects: GA MŠk(CZ) LH11033; GA ČR GAP208/11/0105 Institutional support: RVO:61388963 Keywords : europium * complexes * raman optical activity * resonance Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 13.734, year: 2012

Biosorption of radionuclides by snail shell biomass

International Nuclear Information System (INIS)

Dhami, P.S.; Chaudhari, S.D.; Rathinam, M.; Gopalakrishnan, V.; Ramanujam, A.

2001-01-01

The sorption of various radionuclides from low acidic and alkaline medium was studied using biomass of snail shell origin. Quantitative removal of plutonium was achieved when an alkaline waste effluents of PUREX origin at pH 9.4 was treated using this biomass. The sorbed activity was recovered by dissolving it in 1.0 M nitric acid. (author)

Transport of radionuclides in the atmosphere during complex meteorological conditions

International Nuclear Information System (INIS)

Antic, D.; Telenta, B.

1991-01-01

Radionuclides from various sources (nuclear and fossil fuel power plants, nuclear facilities, medical facilities, etc.) are being released to the atmosphere. The meteorological conditions determine the atmospheric turbulence, dispersion, and removal processes of the radionuclides. A two-dimensional version of the cloud model based on the Klemp-Wilhelmson dynamic and Lin et al.'s microphysics and thermodynamics has been adapted and used to simulate the transport of radionuclides emitted from a power plant or other source to the atmosphere. Calculations of the trajectories and radii for a few puffs are included in this paper. These numerical investigations show that the presented model can be used for the transport simulation of radionuclides and for the assessment of the radiological impact of power plants and other sources in safety assessments and comparative studies. Because it can simulate puff trajectories, this model is especially valuable in the presence of complex meteorological conditions

Removal efficiency of radioactive cesium and iodine ions by a flow-type apparatus designed for electrochemically reduced water production.

Directory of Open Access Journals (Sweden)

Takeki Hamasaki

Full Text Available The Fukushima Daiichi Nuclear Power Plant accident on March 11, 2011 attracted people's attention, with anxiety over possible radiation hazards. Immediate and long-term concerns are around protection from external and internal exposure by the liberated radionuclides. In particular, residents living in the affected regions are most concerned about ingesting contaminated foodstuffs, including drinking water. Efficient removal of radionuclides from rainwater and drinking water has been reported using several pot-type filtration devices. A currently used flow-type test apparatus is expected to simultaneously provide radionuclide elimination prior to ingestion and protection from internal exposure by accidental ingestion of radionuclides through the use of a micro-carbon carboxymethyl cartridge unit and an electrochemically reduced water production unit, respectively. However, the removability of radionuclides from contaminated tap water has not been tested to date. Thus, the current research was undertaken to assess the capability of the apparatus to remove radionuclides from artificially contaminated tap water. The results presented here demonstrate that the apparatus can reduce radioactivity levels to below the detection limit in applied tap water containing either 300 Bq/kg of 137Cs or 150 Bq/kg of 125I. The apparatus had a removal efficiency of over 90% for all concentration ranges of radio-cesium and -iodine tested. The results showing efficient radionuclide removability, together with previous studies on molecular hydrogen and platinum nanoparticles as reactive oxygen species scavengers, strongly suggest that the test apparatus has the potential to offer maximum safety against radionuclide-contaminated foodstuffs, including drinking water.

Effect of temperature on the extraction of europium (III) bymixtures of neutral phosphoro-organic extractants from nitrate solutions

International Nuclear Information System (INIS)

Milchlin, E.B.; Khmuran, M.A.; Mikhailichenko, A.I.

1986-01-01

A study has been made of the distribution of microquantities of europium (III) on extraction with neutral phosphoorganic compounds-tri-n-butyl phosphate (TBP), diisooctylmethyl phosphonate (DIOMP),trialkylphosphine oxide with dissimilar radicals (PODR), or mixtures thereof-from a solution of 2 mole/liter NH 4 NO 3 and 0.01 mole/liter HNO 3 , in the temperature range 20-60 0 C. A temperature rise results in a decrease of the distribution coefficients of the europium on extraction by all of the extractants tested and their mixtures, and also in a reduction of the synergistic effect in extraction by mixtures of the extractants. Based on an investigation of the temperature dependences of the distribution constants of europium nitrate upon extraction by TBP, DIOMP, PODR, or their mixtures, values have been determined for the enthalpy, free energy, and entropy of extraction. It is shown that the enthalpy (-ΔH) increases in the order TBP< DIOMP< PODR. In an extraction with mixed extractants, the enthalpy has a value intermediate between those with the individual extractants. The entropy of extraction (-ΔS) increases in the reverse order PODR< DIOMP< TBP

In vivo toxicity studies of europium hydroxide nanorods in mice

International Nuclear Information System (INIS)

Patra, Chitta Ranjan; Abdel Moneim, Soha S.; Wang, Enfeng; Dutta, Shamit; Patra, Sujata; Eshed, Michal; Mukherjee, Priyabrata; Gedanken, Aharon; Shah, Vijay H.; Mukhopadhyay, Debabrata

2009-01-01

Lanthanide nanoparticles and nanorods have been widely used for diagnostic and therapeutic applications in biomedical nanotechnology due to their fluorescence and pro-angiogenic properties to endothelial cells, respectively. Recently, we have demonstrated that europium (III) hydroxide [Eu III (OH) 3 ] nanorods, synthesized by the microwave technique and characterized by several physico-chemical techniques, can be used as pro-angiogenic agents which introduce future therapeutic treatment strategies for severe ischemic heart/limb disease, and peripheral ischemic disease. The toxicity of these inorganic nanorods to endothelial cells was supported by several in vitro assays. To determine the in vivo toxicity, these nanorods were administered to mice through intraperitoneal injection (IP) everyday over a period of seven days in a dose dependent (1.25 to 125 mg kg -1 day -1 ) and time dependent manner (8-60 days). Bio-distribution of europium elements in different organs was analyzed by inductively coupled plasma mass spectrometry (ICPMS). Short-term (S-T) and long-term (L-T) toxicity studies (mice euthanized on days 8 and 60 for S-T and L-T, respectively) show normal blood hematology and serum clinical chemistry with the exception of a slight elevation of liver enzymes. Histological examination of nanorod-treated vital organs (liver, kidney, spleen and lungs) showed no or only mild histological changes that indicate mild toxicity at the higher dose of nanorods.

Electroplex emission from a layer of a mixture of a europium complex and tris(8-quinolinolato) aluminum

Science.gov (United States)

Cao, Hong; Gao, Xicun; Huang, Chun-Hui

2000-07-01

With a europium complex, tris(α-thenoyltrifluoroacetonato) bis(triphenylphosphine oxide) europium (Eu(TTA) 3(TPPO) 2), as the light-emitting layer, N, N'-diphenyl- N, N'-di( m-tolyl)-benzidine (TPD) as the hole transport layer and tris(8-quinolinolato) aluminum (ALQ) as the electron transport layer, the triple-layer electroluminescent (EL) device emits red light characteristic of Eu 3+ emission. However, as the mixture of Eu(TTA) 3(TPPO) 2 and ALQ is co-evaporated as the light-emitting layer to form a bilayer EL device, a new wide-banded emission peaked at c. 640 nm was obtained. This emission is neither from ALQ nor from the europium complex. The photoluminescence (PL) of the thin film on quartz substrate evaporated from one mixed solid powder of Eu(TTA) 3(TPPO) 2 and ALQ is composed of distinct PL emissions of Eu(TTA) 3(TPPO) 2 and ALQ, denying an exciplex formation mechanism. It is impossible to form a host-guest system. We propose that the EL emission peaked at c. 640 nm is from an electroplex route: a transition between the lowest unoccupied molecular orbital (LUMO) of Eu(TTA) 3(TPPO) 2 and the highest occupied molecular orbital (HOMO) of ALQ.

Development of low-activation design method for reduction of radioactive waste (4). Development of low-activation cement

International Nuclear Information System (INIS)

Ichitsubo, Koki; Tanosaki, Takao; Miura, Keiichi; Tomotake, Hiroichi; Yamada, Kazunori; Fujita, Hideki; Kinno, Masaharu; Hasegawa, Akira

2008-01-01

When nuclear plants will reach to decommission stage, a huge amount of concrete should be disposed as radioactive waste. To reduce the amount of radioactive concrete, the most effective methodology is not to use the materials of high radionuclide content such as coal ash and blast furnace slag, and to use limestone as additives or aggregate. However, concrete uses Portland cement for hardening, therefore, it is difficult to reduce the amount of radioactive concrete unless radionuclide content in cement is reduced. So in this study, we tried to develop the new type of Low-activation cement by reducing of radionuclide as europium and cobalt. As a result, we could reduce the amount of europium and cobalt in cement significantly, and obtained the result that the new cements can reduce radioactivity to one-third or less against commercially Portland cement in Japan. (author)

Sorption of selenium on Mg-Al and Mg-Al-Eu layered double hydroxides

International Nuclear Information System (INIS)

Curtius, H.; Paparigas, Z.; Kaiser, G.

2008-01-01

Salt domes represent deep geological formations which are under consideration as final repositories for irradiated research reactor fuel elements. For long-term safety aspects the mobilisation of the radionuclides due to a water ingress is intensively investigated. At the Institute of Energy Research (IEF-6), leaching experiments were performed in a hot cell facility with UAl x -Al and U 3 Si 2 -Al dispersed research reactor fuel elements in repository-relevant MgCl 2 -rich salt brines under anaerobic conditions. The fuel plates corroded completely within one year and a Mg-Al-layered double hydroxide (LDH) with chloride as interlayer anion was identified as one crystalline phase component of the corrosion products (secondary phases). This Mg-Al-LDH was synthesized, characterized, and the ability to retard europium by an incorporation process was investigated. Europium, as a representative for lanthanides, was identified to be one of the radionuclides which were found in the corrosion products. We could show that europium was incorporated in the lattice structure. LDHs have high anion exchange capacities that enhance their potential to remove anionic contaminants from aqueous systems. In this work the sorption behaviour of selenium in the chemical form as selenite (SeO 3 2- ) on Mg-Al-LDH and on Mg-Al-Eu-LDH was investigated. Especially the influence of the larger europium-III ion was of interest. It represents in the Mg-Al-Eu-LDH about 10% of the molar aluminium amount. The sorption has been experimentally studied in a wide range of pH, ionic strength, radionuclide and sorbent concentration. Both LDHs with chloride as interlayer anion were synthesized by a coprecipitation method under controlled conditions, and their main physico-chemical properties were analyzed prior to the sorption experiments. The sorption kinetics of selenite on the LDHs in water and in MgCl 2 -rich brine were rapid using a LDH concentration of 10 g/L. Equilibrium, indicated by stable p

Innovative methods to stabilize liquid membranes for removal of radionuclides from groundwater

Energy Technology Data Exchange (ETDEWEB)

Lokhandwala, K. [Membrane Technology and Research, Inc., Menlo Park, CA (United States)

1997-10-01

In this Phase I Small Business Innovation Research program, Membrane Technology Research, Inc., is developing a stable liquid membrane for extracting uranium and other radionuclides from groundwater. The improved membrane can also be applied to separation of other metal ions from aqueous streams in industrial operations.

Crystal agglomeration of europium oxalate in reaction crystallization using double-jet semi-batch reactor

International Nuclear Information System (INIS)

Kim, Woo-Sik; Kim, Woon-Soo; Kim, Kwang-Seok; Kim, Joon-Soo; Ward, Michael D.

2004-01-01

The particle agglomeration of europium oxalate was investigated in a double-jet semi-batch reactor over a wide range of operating variables, including the agitation speed, reactant feed rate, and reactant concentration. The size of the agglomerates was directly dictated by the particle collision and supersaturation promoting agglomeration and the fluid shear force inhibiting agglomeration. Thus, with a longer feeding time and higher feed concentration for the reaction crystallization, the mean particle size increased, while the corresponding total particle population decreased due to the enhanced chance of particle agglomeration, resulting from a longer residence time and higher supersaturation in the reactor. Agitation was found to exhibit a rather complicated influence on particle agglomeration. Although both particle collision and turbulent fluid shear were promoted by an increase in the mixing intensity, the crystal agglomeration of europium oxalate was maximized at around 500 rpm of agitation speed due to an optimized balance between particle aggregation and breakage

Resonance ionization spectroscopy of Europium The first application of the PISA at ISOLDE-RILIS

CERN Document Server

AUTHOR|(CDS)2099873; Marsh, Bruce Alan

The following work has been carried out at the radioactive ion beam facility ISOLDE at CERN. A compact atomic beam unit named PISA (Photo Ionization Spectroscopy Apparatus) has been implemented as a recent addition to the laboratory of the Resonance Ionization Laser Ion Source (RILIS). The scope of this thesis work was to demonstrate different applications of the PISA, using the existing and highly developed laser setup of the RILIS installation. In a demonstration of the suitability of PISA for ionization scheme development, a new ionization scheme for Europium has been developed. This resulted in the observation of several new autoionizing states and Rydberg series. Through the analysis of the observed Rydberg resonances a refined value of $45734.33(3)(3)$ cm$^{-1}$ for the ionization potential of the europium atom has been determined. In addition this thesis reports on the feasibility of the use of the PISA as a RILIS performance monitoring device during laser ion source operations. Finally the present wor...

Spectroscopic studies of europium-tetracyclines complexes and their applications in detection of hydrogen peroxide and urea peroxide; Estudos espectroscopicos dos complexos europio-tetraciclinas e suas aplicacoes na detecao de peroxido de hidrogenio e peroxido de ureia

Energy Technology Data Exchange (ETDEWEB)

Grasso, Andrea Nastri

2010-07-01

In this work were studied the spectroscopic properties of trivalent europium ion complexed with components of tetracycline family, chlorotetracycline, oxytetracycline and metacycline, in the presence of hydrogen peroxide and urea peroxide. Optical parameters were obtained such as absorption, emission, lifetime and calibration curves were constructed for luminescence spectra. Experiments were carried out with both inorganic compounds and europium-tetracyclines complexes in order to verify possible interferences. Studies for glucose determination were also described using europium-tetracyclines complexes as biosensors. Results show that europium tetracyclines complexes emit a narrow band in the visible region and, in the presence of hydrogen peroxide or urea peroxide there is a greater enhancement in their luminescence and lifetime. Thus, europium-tetracyclines complexes studied can be used as biosensors for hydrogen and urea peroxides determination as a low cost and room temperature method. An indirect method for glucose determination was studied by adding glucose oxidase enzyme in europium-tetracyclines complex in the presence of glucose promoting as product hydrogen peroxide. (author)

Development and testing of inorganic sorbents made by the internal gelation process for radionuclide and heavy metal separations

International Nuclear Information System (INIS)

Egan, B.Z.; Collins, J.L.; Anderson, K.K.; Chase, C.W.

1995-01-01

The objectives of this task are to develop, prepare, and test microspheres and granular forms of inorganic ion exchangers to remove radionuclides and heavy metals from waste streams occurring at various sites. Several inorganic materials, such as hexacyanoferrates, titanates, phosphates, and oxides have high selectivities and efficiencies for separating and removing radionuclides such as uranium, technetium, cesium, and strontium, and metals such as cobalt, silver, zinc, and zirconium from aqueous waste streams. However, these sorbents frequently exist only as powders and consequently are not readily adaptable to continuous processing such as column chromatography. Making these inorganic ion exchangers as microspheres or granular forms improves the flow dynamics for column operations and expands their practical applications. Microspheres of several materials have been prepared at ORNL, and the effectiveness of zirconium monohydrogen phosphate and hydrous titanium oxide microspheres for removing radionuclides from hot cell waste solutions has been demonstrated

Hydrology and radionuclide migration program

International Nuclear Information System (INIS)

Marsh, K.V.

1992-02-01

This report presents results from the Lawrence Livermore National Laboratory's participation in the Hydrology and Radionuclide Migration Program at the Nevada Test Site (NTS) during fiscal year 1988. The report discusses studies at a new well 100 m down the hydrologic gradient from the previous sampling point at the Cheshire site; laboratory investigations of the mineralogical composition of NTS colloids; the strength of colloidal deposits and parameters affecting their formation and release; accelerator mass spectrometric measurements of 129 I in water from the Cheshire stie; 222 Rn concentrations in water from several pumped wells at the NTS; and a description of a new well (PM3) drilled off the NTS near Area 20. Further studies on groundwater sampled show that both technetium and iodine are quite mobile; both closely track the trend of the decreasing tritium concentration with increasing distance. Antimony and cesium concentrations decrease much more rapidly than tritium, and europium was not detected at all in the new well. Colloidal particles found in water collected from the Cheshire cavity are in size range of 0.050 to 0.003 μm and are dominated by quartz and (Ca, K) feldspars. A new well was drilled on US Air Force land adjacent to the NTS Area 20. Static water level measurements and geochemical data from this well will help to determine the extent to which Pahute Mesa base flow infiltrates Oasis Valley. Preliminary results indicate tritium concentrations in water samples from this well to be in the range of 0.1 to 0.4 pCi/ml as measured under field conditions

Europium-doped calcium titanate: Optical and structural evaluations

Energy Technology Data Exchange (ETDEWEB)

Mazzo, Tatiana Martelli; Pinatti, Ivo Mateus [INCTMN, LIEC, Departamento de Química, Universidade Federal de São Carlos, P.O. Box 676, 13565-905 São Carlos, SP (Brazil); Macario, Leilane Roberta [INCTMN, LIEC, Instituto de Química, Universidade Estadual Paulista, P.O. Box 355, 14800-900 Araraquara, SP (Brazil); Avansi, Waldir [Centro de Ciências Exatas e de Tecnologia, Departamento de Física, Universidade Federal de São Carlos, Jardim Guanabara, 13565-905 São Carlos, SP (Brazil); Moreira, Mario Lucio [Instituto de Física e Matemática, Universidade Federal de Pelotas, P.O. Box 354, Campus do Capão do Leão, 96001-970 Pelotas, RS (Brazil); Rosa, Ieda Lucia Viana, E-mail: ilvrosa@ufscar.br [INCTMN, LIEC, Departamento de Química, Universidade Federal de São Carlos, P.O. Box 676, 13565-905 São Carlos, SP (Brazil); Mastelaro, Valmor Roberto [Instituto de Física de São Carlos, Departamento de Física e Ciência dos Materiais, Universidade de São Paulo, P.O. Box 369, Av Trabalhador São Carlense 400, 13560-970 São Carlos, SP (Brazil); Varela, José Arana; Longo, Elson [INCTMN, LIEC, Instituto de Química, Universidade Estadual Paulista, P.O. Box 355, 14800-900 Araraquara, SP (Brazil)

2014-02-05

Highlights: • CaTiO{sub 3}:Eu{sup 3+} were obtained using low temperatures and very short reactional times. • The Eu{sup 3+} changes the local order–disorder of the [TiO{sub 6}] and [CaO{sub 12}] clusters. • Lifetime decay curves reveal two sites of symmetry of the Eu{sup 3+} in the CT matrix. • CaTiO{sub 3}:Eu{sup 3+} exhibit the strongest luminescent intensity and pure red color. -- Abstract: Pure Calcium Titanate (CT-pure) and Europium doped Calcium Titanate Ca{sub 1−x}Eu{sub x}TiO{sub 3} (x = 0.5%, 1.0% and 2.0% molar ratio of Eu{sup 3+} ions) powders were synthesized by hydrothermal microwave method (HTMW) at 140 °C for 8 min. The HTMW method appears to be an efficient method to prepare the luminescence materials using low temperatures and very short reactional times. In addition it is possible to determine specific correlations imposed by TiCl{sub 4} replacement by titanium isopropoxide [Ti(OC{sub 3}H{sub 7}){sub 4}] changing the reaction character and resulting in two different options of europium doping CT syntesis. To evaluate the influence of the structural order–disorder among the reactions and different properties of these materials, the following techniques were used for characterization. XANES spectroscopy that revealed that the introduction of Eu{sup 3+} ions into the CT lattice induces to significant changes in the local order–disorder around both, [TiO{sub 6}] and [CaO{sub 12}], complex clusters. PL spectra show Eu{sup 3+} emission lines ascribed to the Eu{sup 3+} transitions from {sup 5}D{sub 0} excited states to {sup 7}F{sub J} (J = 0, 1–4) fundamental states in CT:Eu{sup 3+} powders excited at 350 and 394 nm.

Interaction between water, sediments and radionuclides

International Nuclear Information System (INIS)

Snodgrass, W.J.; McKee, P.; Garnett, J.; Stieff, L.

1988-08-01

A model-based measurements program was carried out to evaluate the primary mechanisms controlling transport of uranium 238 and thorium 232 decay chain radionuclides in Quirke Lake, a water body draining much of the uranium mining and milling district near Elliot Lake, Ontario. This program included studies of radionuclide accumulation in sediments, particle settling and lake mass-balance studies. Also, sediment studies were undertaken to evaluate chemical fractionation, mineralogical associations, and sediment-water adsorption and release. A limnocorral experiment was conducted in an isolated portion of a lake to measure radium 226 removal from the water column and diffusion from the sediments back to the water. Modelling studies were made to assess the data. Substantial agreement was obtained using the model originally developed for the AECB between model predictions and observations for Quirke Lake and for the limnocorrals. Further work is required to complete the studies undertaken in this project to assess the significance of the efflux of radionuclides from the sediments. These studies include a laboratory program to measure kinetics of adsorption, sediment-water modelling studies of the results and a field measurement program to develop a mass-balance analysis for thorium. (numerous refs)

Summary Report for the Development of Materials for Volatile Radionuclides

Energy Technology Data Exchange (ETDEWEB)

Strachan, Denis M.; Chun, Jaehun; Henager, Charles H.; Matyas, Josef; Riley, Brian J.; Ryan, Joseph V.; Thallapally, Praveen K.

2010-11-22

The materials development summarized here is in support of the Waste Forms campaign, Volatile Radionuclide task. Specifically, materials are being developed for the removal and immobilization of iodine and krypton, specifically 129I and 85Kr. During FY 2010, aerogel materials were investigated for removal and immobilization of 129I. Two aerogel formulations were investigated, one based on silica aerogels and the second on chalcogenides. For 85Kr, metal organic framework (MOF) structures were investigated.

Summary Report for the Development of Materials for Volatile Radionuclides

International Nuclear Information System (INIS)

Strachan, Denis M.; Chun, Jaehun; Henager, Charles H.; Matyas, Josef; Riley, Brian J.; Ryan, Joseph V.; Thallapally, Praveen K.

2010-01-01

The materials development summarized here is in support of the Waste Forms campaign, Volatile Radionuclide task. Specifically, materials are being developed for the removal and immobilization of iodine and krypton, specifically 129I and 85Kr. During FY 2010, aerogel materials were investigated for removal and immobilization of 129I. Two aerogel formulations were investigated, one based on silica aerogels and the second on chalcogenides. For 85Kr, metal organic framework (MOF) structures were investigated.

Structural and optical analysis on europium doped AZrO{sub 3} (A=Ba, Ca, Sr) phosphor for display devices application

Energy Technology Data Exchange (ETDEWEB)

Dubey, Vikas, E-mail: jsvikasdubey@gmail.com [Department of Physics, Bhilai Institute of Technology Raipur, 493661 (India); Tiwari, Neha [Department of Physics, Govt. Model Science College, Jabalpur (India)

2016-05-06

Behavior displayed by europium doped AZrO{sub 3} phosphor which was synthesized by solid state reaction method. For synthesis of BaZrO{sub 3}, SrZrO{sub 3} and CaZrO{sub 3} phosphor with fixed concentration of europium ion was calcination at 1000°C and sintered at 1300°C following intermediate grinding. Synthesized sample was characterized by X-ray diffraction analysis and crystallite sized was calculated by Scherer’s formula. From PL spectra of prepared phosphors shows intense emission centred at 612nm (red emission) with high intensity for SrZrO{sub 3}:Eu{sup 3+}. For europium doped BaZrO{sub 3} and CaZrO{sub 3} (613nm) phosphor shows less intense PL spectra as compared to SrZrO{sub 3}:Eu{sup 3+}. The strong emission peak of AZrO{sub 3}:Eu{sup 3+} phosphor is due to forced electric dipole transition of {sup 5}D{sub 0} to {sup 7}F{sub 2} centered at 612 and 613nm. It is characteristic red emission for europium ion. The excitation spectra of AZrO{sub 3}:Eu{sup 3+} phosphor mainly consists of the charge transfer and (CTB) of Eu{sup 3+} located in 200–350 nm centred at 254nm. The present phosphors can act as single host for red light emission in display devices. The CIE coordinates were calculated by Spectrophotometric method using the spectral energy distribution of the AZrO{sub 3}:Eu{sup 3+} sample.

Europium(III) chelate-dyed nanoparticles as donors in a homogeneous proximity-based immunoassay for estradiol

International Nuclear Information System (INIS)

Kokko, Leena; Sandberg, Kaisa; Loevgren, Timo; Soukka, Tero

2004-01-01

Nanoparticles containing thousands of fluorescent europium(III) chelates have a very high specific activity compared to traditional lanthanide chelate labels. It can be assumed that if these particles are used in a homogeneous assay as donors, multiple chelates can excite a single acceptor in turns and the energy transfer to the acceptor is increased. The principle was employed in an immunoassay using luminescent resonance energy transfer from a long lifetime europium(III) chelate-dyed nanoparticle to a short lifetime, near-infrared fluorescent molecule. Due to energy transfer fluorescence lifetime of the sensitised emission was prolonged and fluorescence could be measured using a time-resolved detection. A competitive homogeneous immunoassay for estradiol was created using 92 nm europium(III) chelate-dyed nanoparticle coated with 17β-estradiol specific recombinant antibody Fab fragments as a donor and estradiol conjugated with near-infrared dye AlexaFluor 680 as an acceptor. The density of Fab fragments on the surface of the particle influenced the sensitivity of the immunoassay. The optimal Fab density was reached when the entire surface of the particle participated in the energy transfer, but the areas where the energy was transferred to a single acceptor, did not overlap. We were able to detect estradiol concentrations down to 70 pmol l -1 (3xSD of a standard containing 0 nmol l -1 of E2) using a 96-well platform. In this study we demonstrated that nanoparticles containing lanthanide chelates could be used as efficient donors in homogeneous assays

Hot demonstration of proposed commercial nuclide removal technology

Energy Technology Data Exchange (ETDEWEB)

Lee, D.D.; Travis, J.R.; Gibson, M.R. [Oak Ridge National Lab., TN (United States)

1997-10-01

Cesium, strontium, and technetium radionuclides are a small fraction of the mainly sodium and potassium salts in storage tank supernatants at the Hanford, Oak Ridge, Savannah River, and Idaho sites that DOE must remediate. Radionuclide removal technologies supplied by the ESP-CP have been previously proposed and tested in small batch and column tests using simulated and a few actual supernatants. They must now be tested and the most appropriate ones selected using a flow system of a scale suitable to obtain engineering data that can be applied to the design of pilot-scale equipment. This task involves operation of an experimental unit designed and constructed to test radionuclide removal technologies during continuous operation on actual supernatants. The equipment diagram, consists of the tanks, pumps, tubing and fittings, filters, and intrumentation for testing radionuclide removal technologies in a continuous-flow system in an Oak Ridge National Laboratory (ORNL) hot cell. The task provides a test bed for investigating new technologies, such as 3M`s SLIG 644 WWL WEB and AEA Technology`s EIX electrochemical elution system, and complements ESP`s comprehensive supernatant task (TTPOR06C341) by using larger engineering-scale, continuous equipment to verify and expand that task`s batch studies. This task complements the Tanks Focus Area`s (TFA`s) Cesium Removal Demonstration (CsRD) at ORNL by providing sorbent selection information, evaluating and testing proposed sorbents, and providing operational experience and characteristics using the sorbent and supernatant to be used in the demonstration, followed by evaluating and comparing small-scale to demonstration-scale performance. The authors cooperate closely with other ESP-CP tasks and the TFA to ultimately transfer the technologies being developed to the end user.

Solid phase microextraction sampling of high explosive residues in the presence of radionuclides and radionuclide surrogate metals

International Nuclear Information System (INIS)

Duff, M.C.; Crump, S.L.; Ray, R.J.; Beals, D.; Cotham, W.E.; Mount, K.; Koons, R.D.; Leggitt, J.

2008-01-01

The Federal Bureau of Investigation (FBI) Laboratory currently does not have on site facilities for handling radioactive evidentiary materials and there are no established FBI methods or procedures for decontaminating high explosive (HE) evidence while maintaining evidentiary value. One experimental method for the isolation of HE residue involves using solid phase microextraction (SPME) fibers to remove residue of interest. Due to their high affinity for organics, SPME fibers should have little affinity for most metals. However, no studies have measured the affinity of radionuclides for SPME fibers. The focus of this research was to examine the affinity of dissolved radionuclide ( 239/240 Pu, 238 U, 237 Np, 85 Sr, 133 Ba, 137 Cs, 60 Co and 226 Ra) and stable radionuclide surrogate metals (Sr, Co, Ir, Re, Ni, Ba, Cs, Nb, Ru, and Nd) for SPME fibers at the exposure conditions that favor the uptake of HE residues. Our results from radiochemical and mass spectrometric analyses indicate these metals have little measurable affinity for these SPME fibers during conditions that are conducive to HE residue uptake with subsequent analysis by liquid or gas phase chromatography with mass spectrometric detection. (author)

On the optimization of empirical data concerning radionuclides in water of Lake Juodis

International Nuclear Information System (INIS)

Tarasiuk, N.; Koviazina, E.; Shliahtich, E.

2004-01-01

Quality of site-dependent water sampling for radionuclide analysis assessing their removal from the complicated aquatic system of eutrophic Lake Juodis is analyzed comparing time courses of site-specific data on standard variables (pH, temperature, redox potential, oxygen concentration, conductivity) in 2003-2004. Compared data were measured simultaneously: a) in the open bottom terrace of the lake adjoining its outflow; b) before the beaver dam bounding the lake rush grown area and c) at the site of the outflowing brook usually used for water sampling for radionuclide analysis. The rush grown area adjoining the outflowing brook is a natural filter for plutonium transport from the lake during warm season as well as for radiocesium activity fraction associated with the suspended matter. Using information on site-specific variations of vertical profiles of standard variables measured in the shallow bottom terrace of the lake, seasonal peculiarities of vertical radionuclide transport in the water column and their release from the sediments are discussed. In winter beaver activities in the lake as well as formation of the anaerobic zone in the rush grown area are considered as supplementary mechanisms facilitating vertical transport of radionuclides in the temperature stratificated water column and their removal from similar lakes. (author)

Influence of natural organic matter on the speciation of radionuclides in a geochemistry context; Influence de la matiere organique naturelle sur la speciation des radionucleides en contexte geochimique

Energy Technology Data Exchange (ETDEWEB)

Marang, L

2007-09-15

The principal aim of this work is the study of the influence of natural organic matter, in particularly humic substances (HS), on the speciation of radionuclides (RN). The studied radionuclides are cobalt (II), europium (III) and uranium (VI). It has been shown that mobility and bioavailability of a metal are related to its speciation. The NICA-Donnan model describes metal ion binding to NOM: it accounts for NOM chemical heterogeneity, competition during binding and ionic strength effects. However the model has been calibrated with a limited number of experimental data for the RN. Indeed there is only a few speciation technique available for the study of the interactions RN-HS. Within the framework of this study, we have developed and optimised speciation technique (Flux Donnan Membrane Technique and the use of an un-solubilized humic acid) in order to acquire new experimental data, we have also studied the effect of the competition on RN speciation and finally we have tested the model capacity to predict the RN behavior in laboratory or in situ. (author)

Structural and photocatalytic properties of iron- and europium-doped TiO2 nanoparticles obtained under hydrothermal conditions

International Nuclear Information System (INIS)

Diamandescu, L.; Vasiliu, F.; Tarabasanu-Mihaila, D.; Feder, M.; Vlaicu, A.M.; Teodorescu, C.M.; Macovei, D.; Enculescu, I.; Parvulescu, V.; Vasile, E.

2008-01-01

Iron- and europium-doped (≤1 at.%) TiO 2 nanoparticles powders have been synthesized by a hydrothermal route at 200 deg. C, starting with TiCl 4 , FeCl 3 .6H 2 O and EuCl 3 .6H 2 O. The structure, morphology and optical peculiarities were investigated by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), extended X-ray absorption fine structure (EXAFS), Moessbauer spectroscopy and UV-vis measurements. The photocatalytic performance was analysed in the photodegradation reaction of phenol. Rietveld refinements of XRD patterns reveal that the as-prepared samples consist in iron- and europium-doped TiO 2 in the tetragonal anatase structural shape, with particle size as low as 15 nm. By means of Moessbauer spectroscopy on both 57 Fe and 151 Eu isotopes as well as by EXAFS analyses, the presence of Fe 3+ and/or Eu 3+ ions in the nanosized powders has been evidenced. It was found that iron and europium ions can substitute for titanium in the anatase structure. From the UV-vis reflection spectra, by using the transformed Kubelka-Munk functions, the band gap energy (E g ) of the hydrothermal samples has been determined in comparison with that of Degussa P-25 photocatalyst. A decrease of E g from 2.9 eV found for Degussa photocatalyst to 2.8 eV for the titania doped with 1 at.% Fe has been evidenced, indicating a valuable absorption shift (∼20 nm) towards visible light region. However, the best photocatalytic activity in the photodegradation reaction of phenol was evidenced for the hydrothermal sample, TiO 2 : 1 at.% Fe, 0.5 at.% Eu, in both UV and visible light regions. The photocatalytic activities of iron-doped and iron-europium-codoped samples are high and practically the same only in visible light. The photocatalytic properties in correlation with the structural and optical peculiarities of the hydrothermal samples are discussed

Radionuclide sorption in soils and sediments: oxide-organic matter competition

International Nuclear Information System (INIS)

Maes, A.; Cremers, A.

1986-01-01

This paper deals with the speciation of europium in the solid phase and liquid phase extracts of Boom Clay under in situ conditions. Using a new method for measuring the europium-humic acid complex stability constant at high pH, it is shown that carbonate complexation is poorly competitive with humic acid, europium being quantitatively present as humic acid complex, its stability constant being of the order of 10 12 -10 13 . It is furthermore shown that partial oxidation of the sediment, which is strongly reducing under in situ conditions, leads to a significant increase in Ksub(D) values, whatever the liquid/solid ratio used. This effect is ascribed to the involvement of ferric oxides which are generated in the solid phase and which lead to a displacement of the metal from the humic acid sink. Some examples are presented which demonstrate that at high pH, around 9, ferric oxides may be competitive with humic acids for metal sorption and that this effect increases with pH. (author)

Radionuclide sorption in soils and sediments: Oxide - organic matter competition

International Nuclear Information System (INIS)

Maes, A.; Cremers, A.

1985-01-01

This paper deals with the speciation of europium in the solid phase and liquid phase extracts of Boom clay under in situ conditions. Using a new method for measuring the europium-humic acid complex stability constant at high pH, it is shown that carbonate complexation is poorly competitive with humic acid, europium being quantitatively present as humic acid complex, its stability constant being of the order of 10/sup 12/--10/sup 13/. It is furthermore shown that partial oxidation of the sediment, which is strongly reducing under in situ conditions, leads to a significant increase in K/sub D/ values, whatever the liquid/solid ratio used. This effect is ascribed to the involvement of ferric oxides which are generated in the solid phase and which lead to a displacement of the metal from the humic acid sink. Some examples are presented which demonstrate that a high pH, around 9, ferric oxides may be competitive with humic acids for metal sorption and that this effect increases with pH

Characterization of photoluminescent europium doped yttrium oxide thin-films prepared by metallorganic chemical vapor deposition

International Nuclear Information System (INIS)

McKittrick, J.; Bacalski, C.F.; Hirata, G.A.; Hubbard, K.M.; Pattillo, S.G.; Salazar, K.V.; Trkula, M.

1998-01-01

Europium doped yttrium oxide, (Y 1-x Eu x ) 2 O 3 , thin-films were deposited on silicon and sapphire substrates by metallorganic chemical vapor deposition (MOCVD). The films were grown in a MOCVD chamber reacting yttrium and europium tris(2,2,6,6-tetramethyl-3,5,-heptanedionates) precursors in an oxygen atmosphere at low pressures (5 Torr) and low substrate temperatures (500--700 C). The films deposited at 500 C were flat and composed of nanocrystalline regions of cubic Y 2 O 3 , grown in a textured [100] or [110] orientation to the substrate surface. Films deposited at 600 C developed from the flat, nanocrystalline morphology into a plate-like growth morphology oriented in the [111] with increasing deposition time. Monoclinic Y 2 O 3 :Eu 3+ was observed in x-ray diffraction for deposition temperatures ≥600 C on both (111) Si and (001) sapphire substrates. This was also confirmed by the photoluminescent emission spectra

The enthalpies of formation of neutral and charged components of saturated vapor over europium dichloride

International Nuclear Information System (INIS)

Pogrebnoj, A.M.; Kudin, L.S.

2003-01-01

Composition of saturated vapor over europium dichloride was studied by the method of high-temperature mass spectrometry in the temperature range of 1154 - 1267 K. For neutral components of the vapor, represented by monomer and dimer molecules, partial pressures were determined. Enthalpies of sublimation of europium dichloride Δ s H 0 (298 K) as monomers (338 ± 9) and dimers (407 ± 20 kJ/mol) were calculated. Equilibrium constants of ion-molecular and ion-ionic reactions were measured, their enthalpies being ascertained. Enthalpies of formation of molecules and ions Δ f H 0 (298 K) were calculated: -486 ± 11 (EuCl 2 ), -1242 ± 22 (Eu 2 Cl 4 ), 1 ± 12 (Eu 2 Cl 2 + ), -347 ± 20 (Eu 2 Cl 3 + ), -1111 ± 42 (Eu 3 Cl 5 + ), -975 ± 20 (EuCl 3 - ), -1309 ± 17(EuCl 4 - ), -1734 ± 20 (Eu 2 Cl 5 - ) kJ/mol [ru

Incorporation of europium III complex into nanoparticles and films obtained by the Sol-Gel methodology

Directory of Open Access Journals (Sweden)

Faley Jean de Sousa

2010-03-01

Full Text Available The sol-gel process is very effective for the preparation of new materials with potential applications in optics, sensors, catalyst supports, coatings, and specialty inorganic polymers that can be used as hosts for the accommodation of organic molecules. The low temperature employed in the process is the main advantage of this methodology. In this work, the europium (III complex with 1,10-phenantroline was prepared, and this luminescent complex was incorporated into silica nanoparticles and films by the sol-gel process. The nanoparticles were obtained by the modified Stöber methodology. The films were obtained by the dip-coating technique, at different deposition rates and numbers of layers. The nanoparticles and films were characterized by photoluminescence, thermal analysis, and Raman and infrared spectroscopies. Characterization revealed that the europium (III complex was not affected upon incorporation into the nanoparticles and films, opening a new field for the application of these materials.

Radionuclide toxicity

International Nuclear Information System (INIS)

Galle, P.

1982-01-01

The aim of this symposium was to review the radionuclide toxicity problems. Five topics were discussed: (1) natural and artificial radionuclides (origin, presence or emission in the environment, human irradiation); (2) environmental behaviour of radionuclides and transfer to man; (3) metabolism and toxicity of radionuclides (radioiodine, strontium, rare gas released from nuclear power plants, ruthenium-activation metals, rare earths, tritium, carbon 14, plutonium, americium, curium and einsteinium, neptunium, californium, uranium) cancerogenous effects of radon 222 and of its danghter products; (4) comparison of the hazards of various types of energy; (5) human epidemiology of radionuclide toxicity (bone cancer induction by radium, lung cancer induction by radon daughter products, liver cancer and leukaemia following the use of Thorotrast, thyroid cancer; other site of cancer induction by radionuclides) [fr

Mapping of Natural Radionuclides using Noise Adjusted Singular Value Decomposition, NASVD

DEFF Research Database (Denmark)

Aage, Helle Karina

2006-01-01

Mapping of natural radionuclides from airborne gamma spectrometry suffer from random ”noise” in the spectra due to short measurement times. This is partly compensated for by using large volume detectors to improve the counting statistics. One method of further improving the quality of the measured...... spectra is to remove from the spectra a large fraction of this random noise using a special variant of Singular Value Decomposition: Noise Adjusted Singular Value Decomposition. In 1997-1999 the natural radionuclides on the Danish Island of Bornholm were mapped using a combination of the standard 3...

Preparation and luminescence of silica aerogel composites containing an europium (III) phenanthroline nitrate complex

Energy Technology Data Exchange (ETDEWEB)

Gutzov, Stoyan, E-mail: sgutzov@chem.uni-sofia.bg [University of Sofia “St. Kliment Ohridski”, Department of Physical Chemistry, J. Bourchier Blvd. 1, 1164 Sofia (Bulgaria); Danchova, Nina; Kirilova, Rada; Petrov, Vesselin [University of Sofia “St. Kliment Ohridski”, Department of Physical Chemistry, J. Bourchier Blvd. 1, 1164 Sofia (Bulgaria); Yordanova, Stanislava [University of Sofia “St. Kliment Ohridski”, Department of Organic Chemistry, J. Bourchier Blvd. 1, 1164 Sofia (Bulgaria)

2017-03-15

A simple two step procedure for the functionalization of hydrophobic silica aerogel microgranules with europium ions and/or 1,10 - phenanthroline is demonstrated. The activation procedure is based on soaking aerogels in a europium nitrate solution, followed by functionalization with 1,10 – phenanthroline. The functionalized materials display strong red or blue emission at UV-excitation, coming from the formation of [Eu(phen){sub 2}](NO{sub 3}){sub 3} or Si(IV)– 1,10-phenathroline complexes in the porous system of the aerogels. The most probable site symmetry of the europium cation is C{sub 2v} confirmed by luminescence spectra analysis. Room temperature diffuse reflectance spectra and excitation/luminescence spectra are used to describe the optical properties of the hybrid composites. Excitation spectra prove an efficient energy transfer between 1,10 – phenanthroline and the Eu{sup 3+} ion. - Graphical abstract: An effective activation procedure for functionalization of silica aerogel granules with [Eu(phen){sub 2}](NO{sub 3}){sub 3} and/or 1,10 – phenanthroline /phen/ has been demonstrated in order to obtain red or blue emitting materials. Luminescence spectra (excitation at 355 nm) of functionalized aerogel granules: 1 – SiO{sub 2}:0.18phen; 2 – [Eu(phen){sub 2}](NO{sub 3}){sub 3}; 3– SiO{sub 2}:0.007Eu(phen){sub 2}(NO{sub 3}){sub 3}. The Eu{sup 3+} f-f {sup 5}D{sub 0} →{sup 7}F {sub 0,1,2,3,4} emission transitions are denoted as 0-0, 0-1, 0-2, 0-3, 0-4. The most probable site symmetry of Eu3{sup +} ion is C{sub 2v}.

Synthesis and structural characterization of an unusual heterometallic europium(III) amidinate complex

International Nuclear Information System (INIS)

Sroor, Farid M.; Hrib, Cristian G.; Hilfert, Liane; Edelmann, Frank T.

2015-01-01

The reaction of EuI_2(THF)_2 with 3 equiv. of the recently discovered lithium-cyclopropylethinylamidinate Li[c-C_3H_5-C≡C-C(NCy)_2] (1) (Cy = cyclohexyl) unexpectedly afforded the heterometallic europium(III) amidinate complex [{c-C_3H_5-C≡C-C(NCy)_2}Li{c-C_3H_5-C≡C-C(NCy)_2}_2Eu(μ-I)_2Li(THF)_2] (2) in the form of bright yellow, air- and moisture-sensitive crystals. An X-ray diffraction study of 2 revealed several unusual structural features. It comprises a double ''ate'' complex of the tentative trivalent europium(III) bis(cyclopropylethinylamidinate) derivative [c-C_3H_5-C≡C-C(NCy)_2]_2Eu"I"I"II. ''Ate'' complex formation occurred not only through retention of one equiv. of lithium iodide but also through addition of one equiv. of Li[c-C_3H_5-C≡C-C(NCy)_2]. The Li atom in the iodo-bridged Eu(μ-I)_2Li(THF)_2 part of the molecule is tetrahedrally coordinated, whereas the second lithium atom is only tricoordinate through the presence of a rare monodentate (dangling) amidinate ligand. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Thermal expansion studies on europium titanate (Eu2TiO5)

International Nuclear Information System (INIS)

Panneerselvam, G.; Subramanian, G.G.S.; Antony, M.P.

2008-01-01

The lattice thermal expansion characteristics of europium titanate (Eu 2 TiO 5 ) have been studied by measuring the lattice parameter by high temperature X-ray diffraction technique (HT-XRD) in the temperature range 298-1573K. Percentage linear thermal expansion and mean linear thermal expansion coefficients were computed from the lattice parameter data. The percentage linear thermal expansion in the temperature range 298-1573 K along a, b and c axes are 1.05, 1.15 and 0.95 respectively. (author)

Natural uranium-series radionuclide inventories in coastal and oceanic waters of the south-western Pacific - insights into trace metal flux and removal pathway analysis

International Nuclear Information System (INIS)

Szymczak, R.; Jeffree, R.A.; Peck, G.A.

2003-01-01

Participate scavenging of trace metals plays a major role in determining their ecosystem flux and incident dissolved concentrations. Differences in the half-lives and biogeochemical behaviour of natural uranium series radioisotope pairs (eg. 238 U/ 234 Th, 210 Pb/ 210 Po) allow their application as oceanic process tracers. Coincidental measurements of dissolved and particulate trace element concentrations and inventories of radionuclides in the Noumea coral lagoon and adjacent offshore waters were used to quantify water column flux rates and provide insights on removal pathway analysis. Understanding prevailing pathways and respective flux rates of pollutants in specific coastal and oceanic systems will assist to establish the fate and consequence of pollutants and allow sustainable management strategies to be developed. Both natural and pollutant chemical species introduced to the marine environment may either remain benign in solution or undergo physiological uptake by biota, but most often associate with colloids and fine particles, which subsequent undergo aggregation, sedimentation and removal to the sea floor

Internal-standard method for the determination of uranium, thorium, lanthanum and europium in carbonaceous shale and monazite by epithermal neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Chen, Shuenn-Gang; Tsai, Hui-Tuh; Wu, Shaw-Chii [Institute of Nuclear Energy Research, Lung-Tan (Taiwan, Republic of China)

1981-10-03

An internal-standard method was applied for the determination of uranium, thorium, lanthanum and europium is carbonaceous shale samples and monazite sand by epithermal neutron activation analysis using gold as an internal standard element. The samples were irradiated in a zero-power reactor at the Institute of Nuclear Energy Research and measured with a high-resolution Ge(Li) detector. The detection limit is 0.1 ppm for uranium and europium, 1 ppm for thorium, 5 ppm for lanthanum, and the realative error of all elements is within +-2.6%.

Systematic investigation and in vitro biocompatibility studies on mesoporous europium doped hydroxyapatite

OpenAIRE

Popa Cristina; Ciobanu Carmen; Iconaru Simona; Stan Miruna; Dinischiotu Anca; Negrila Constantin; Motelica-Heino Mikael; Guegan Regis; Predoi Daniela

2014-01-01

International audience; This paper reports a systematic investigation on europium doped hydroxyapatite (Eu:HAp). In this work, a set of complementary techniques Fourier Transform Infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and, Brunauer-Emmett-Teller (BET) technique was used to allowing a proper understanding of Eu:HAp. The XPS analysis confirmed the substitution of Ca ions by Eu ions in Eu:HAp samples. Eu:HAp and pure HAp show ...

Methods of separating short half-life radionuclides from a mixture of radionuclides

International Nuclear Information System (INIS)

Bray, L.A.; Ryan, J.L.

1998-01-01

The present invention is a method of obtaining a radionuclide product selected from the group consisting of 223 Ra and 225 Ac, from a radionuclide ''cow'' of 227 Ac or 229 Th respectively. The method comprises the steps of (a) permitting ingrowth of at least one radionuclide daughter from said radionuclide ''cow'' forming an ingrown mixture; (b) insuring that the ingrown mixture is a nitric acid ingrown mixture; (c) passing the nitric acid ingrown mixture through a first nitrate form ion exchange column which permits separating the ''cow'' from at least one radionuclide daughter; (d) insuring that the at least one radionuclide daughter contains the radionuclide product; (e) passing the at least one radionuclide daughter through a second ion exchange column and separating the at least one radionuclide daughter from the radionuclide product and (f) recycling the at least one radionuclide daughter by adding it to the ''cow''. In one embodiment the radionuclide ''cow'' is the 227 Ac, the at least one daughter radionuclide is a 227 Th and the product radionuclide is the 223 Ra and the first nitrate form ion exchange column passes the 227 Ac and retains the 227 Th. In another embodiment the radionuclide ''cow'' is the 229 Th, the at least one daughter radionuclide is a 225 Ra and said product radionuclide is the 225 Ac and the 225 Ac and nitrate form ion exchange column retains the 229 Th and passes the 225 Ra/Ac. 8 figs

Effect of Some Therapeutic Agents on the Radionuclides Excretion from Internally Contaminated Rats

International Nuclear Information System (INIS)

Aziz, M.; Mangood, Sh.A.; Sohsah, M.A.

2009-01-01

The present work was oriented to investigate the effectiveness of Prussian blue (PB), vermiculite and diethylenetriaminepentaacetic acid (CaDTPA) as therapeutic agents for the elimination of either 134 Cs or 60 Co from contaminated rats after intake of one of the isotopes. The study was performed by using 48 adult rats divided into 8 identical groups each of six rats having approximately the same body weight. The groups included a reference group, without isotope or therapeutic agent administration, four groups given one of the isotopes and four groups given the isotopes and treated with different therapeutic regimes. The isotope content of the treated and untreated contaminated rats were followed by daily whole body radiometric counting for three weeks. On plotting log % radionuclide retained as a function of time, elapsed between radionuclide administration and radiometric counting, straight lines were obtained. The results indicate that excretion can mostly be represented by two stages; the first is fast followed by a second slow stage. The % radionuclide excreted, the corresponding rate constant and the biological half-life of each stage was estimated. It was found that the application of PB + vermiculite is more efficient, to remove 134 Cs, from contaminated rats, than PB only and CaDTPA is more efficient to remove 60Co. Therefore, it is recommended to use the three therapeutic agents to remove both isotopes when taken simultaneously

Comparison of infrared-excited up-converting phosphors and europium nanoparticles as labels in a two-site immunoassay

International Nuclear Information System (INIS)

Ukonaho, Telle; Rantanen, Terhi; Jaemsen, Laura; Kuningas, Katri; Paekkilae, Henna; Loevgren, Timo; Soukka, Tero

2007-01-01

Research in the field of immunoassays and labels used in the detection has been recently focused on particulate reporters, which possess very high specific activity that excludes the label as a sensitivity limiting factor. However, the large size and shape of the particulate labels may produce additional problems to immunoassay performance. The aim of this work was to study with two identical non-competitive two-site immunoassays whether up-converting phosphor (UCP) particles are comparable in performance with europium(III) chelate-dyed nanoparticles as particulate labels. In addition we strived to verify the common assumption of the photostability of up-converting phosphor particles supporting their potential applicability in imaging. Detection limits in two-site immunoassay for free prostate-specific antigen (free-PSA) were 0.53 ng L -1 and 1.3 ng L -1 using two different up-converting phosphors and 0.16 ng L -1 using europium(III) nanoparticle. Large size distribution and non-specific binding of up-converting phosphor particles caused assay variation in low analyte concentrations and limited the analytical detection limit. The non-specific binding was the major factor limiting the analytical sensitivity of the immunoassay. The results suggests the need for nanoscaled and uniformely sized UCP-particles to increace the sensitivity and applicability of up-converting phosphor particles. Anti-Stokes photoluminescence of up-converting phosphor particles did not photobleach when measured repeatedly, on the contrary, the time-resolved fluorescence of europium nanoparticles photobleached relatively rapidly

Methods of separating short half-life radionuclides from a mixture of radionuclides

Science.gov (United States)

Bray, Lane A.; Ryan, Jack L.

1998-01-01

The present invention is a method of obtaining a radionuclide product selected from the group consisting of .sup.223 Ra and .sup.225 Ac, from a radionuclide "cow" of .sup.227 Ac or .sup.229 Th respectively. The method comprises the steps of a) permitting ingrowth of at least one radionuclide daughter from said radionuclide "cow" forming an ingrown mixture; b) insuring that the ingrown mixture is a nitric acid ingrown mixture; c) passing the nitric acid ingrown mixture through a first nitrate form ion exchange column which permits separating the "cow" from at least one radionuclide daughter; d) insuring that the at least one radionuclide daughter contains the radionuclide product; e) passing the at least one radionuclide daughter through a second ion exchange column and separating the at least one radionuclide daughter from the radionuclide product and f) recycling the at least one radionuclide daughter by adding it to the "cow". In one embodiment the radionuclide "cow" is the .sup.227 Ac, the at least one daughter radionuclide is a .sup.227 Th and the product radionuclide is the .sup.223 Ra and the first nitrate form ion exchange column passes the .sup.227 Ac and retains the .sup.227 Th. In another embodiment the radionuclide "cow"is the .sup.229 Th, the at least one daughter radionuclide is a .sup.225 Ra and said product radionuclide is the .sup.225 Ac and the .sup.225 Ac and nitrate form ion exchange column retains the .sup.229 Th and passes the .sup.225 Ra/Ac.

Decontamination of radionuclides on construction materials

International Nuclear Information System (INIS)

Samuleev, P.V.; Andrews, W.S.; Creber, K.A.M.; Velicogna, D.

2013-01-01

A wide variety of materials can become contaminated by radionuclides, either from a terrorist attack or an industrial or nuclear accident. The final disposition of these materials depends, in large part, on the effectiveness of decontamination measures. This study reports on investigations into the decontamination of a selection of building materials. The aim has been to find an effective, easy-to-use and inexpensive decontamination system for radionuclides of cesium and cobalt, considering both the chemical and physical nature of these potential contaminants. The basic method investigated was surface washing, due to its ease and simplicity. In the present study, a basic decontamination formulation was modified by adding isotope-specific sequestering agents, to enhance the removal of cesium(I) and cobalt(II) from such construction materials as concrete, marble, aluminum and painted steel. Spiking solutions contained 134 Cs or 60 Co, which were prepared by neutron activation in the SLOWPOKE-2 nuclear reactor facility at the Royal Military College of Canada. Gamma spectroscopy was used to determine the decontamination efficiency. The results showed that the addition of sequestering agents generally improved the radiological decontamination. Although the washing of both cesium and cobalt from non-porous materials, such as aluminum and painted steel, achieved a 90-95 % removal, the decontamination of concrete and marble was more challenging, due to the porous nature of the materials. Nevertheless, the removal efficiency from 6-year-old concrete increased from 10 % to approximately 50 % for cobalt(II), and from 18 to 55 % for cesium(I), with the use of isotope binding agents, as opposed to a simple water wash. (author)

The removal of radionuclides from contaminated milk and meat

International Nuclear Information System (INIS)

Long, S.C.; Sequeira, S.; Pollard, D.; Fedin, F.A.; Krylova, N.V.

1996-01-01

The transfer of radiocesium and radiostrontium from milk to a number of commonly consumed European and Ukrainian cheeses was quantified. The F f 1 for radiocesium in these cheeses was typically between 0.5 and 0.7, while that for radiostrontium ranged from 0.7 to 8.3. Those steps during the cheese making process that resulted in removal of radiocesium were then identified. The production of cheeses by modified technologies succeeded in reducing the radiostrontium transfer by a small amount. Acidification of the milk (to a pH < 5.1) prior to coagulation resulted in a significantly smaller transfer of radiostrontium to the cheese. The coagulation process varied by up to 20% for duplicate experiments. At least 50% of radiocesium may be removed from contaminated meat by soaking in NaCI solution (brine). Greater removal (up to 90%) may be achieved by varying treatment parameters. The losses of vitamins and minerals associated with this treatment were quantified

Past and present levels of some radionuclides in fish from Bikini and Enewetak Atolls.

Science.gov (United States)

Noshkin, V E; Robison, W L; Wong, K M; Brunk, J L; Eagle, R J; Jones, H E

1997-07-01

Bikini and Enewetak were the sites in the Northern Marshall Islands that were used by the United States as testing grounds for nuclear devices between 1946 and 1958. The testing produced close-in fallout debris that was contaminated with different radionuclides and which entered the aquatic environment. The contaminated lagoon sediments became a reservoir and source term of manmade radionuclides for the resident marine organisms. This report contains a summary of all the available data on the concentrations of 137Cs, 60Co and 207Bi in flesh samples of reef and pelagic fish collected from Bikini and Enewetak Atolls between 1964 and 1995. The selection of these three radionuclides for discussion is based on the fact that these are the only radionuclides that have been routinely detected by gamma spectrometry in flesh samples from all fish for the last 20 y. Flesh from fish is an important source of food in the Marshallese diet. These radionuclides along with the transuranic radionuclides and 90Sr contribute most of the small radiological dose from ingesting marine foods. Some basic relationships among concentrations in different tissues and organs are discussed. The reef fish can be used as indicator species because their body burden is derived from feeding, over a lifetime, within a relatively small contaminated area of the lagoon. Therefore, the emphasis of this report is to use this extensive and unique concentration data base to describe the effective half lives and cycling for the radionuclides in the marine environments during the 31-y period between 1964 and 1995. The results from an analysis of the radionuclide concentrations in the flesh samples indicate the removal rates for the 3 radionuclides are significantly different. 137Cs is removed from the lagoons with an effective half life of 9-12 y. Little 60Co is mobilized to the water column so that it is depleted in both environments, primarily through radioactive decay. The properties of 207Bi are different

Influence of natural mobile organic matter on europium retention on Bure clay rock

International Nuclear Information System (INIS)

Vu-Do, Laurence

2013-01-01

Bure clay rock (CR) was chosen as host rock for the French high and intermediate level long lived radioactive waste repository. This choice is mostly explained by the retention ability of the Callovo-Oxfordian rock (COx). Bure clay rock contains natural organic matter (OM) that could have an influence on radionuclide retention. The aim of this work is to assess the influence of natural mobile OM on the retention of Eu on clay rock. Eu was chosen as a chemical model for trivalent actinides contained in vitrified waste. Three organic molecules were studied: suberic, sorbic and tiglic acids, small organic acids identified in COx pore water. All the experiments were carried out in an environment recreating COx water (pH=7.5; I=0.1 mol/L; PCO 2 =10 -2 bar).Clay rock sample characterization showed that the sample used in this work was similar to those previously extracted from the area of interest and that it was necessary to maintain pH at 7.5 to avoid altering the clay rock. The Eu-OM system study indicated that organic acids had no influence on Eu speciation in COx water. The Eu-CR system experimental study confirmed that retention implied sorption on CR (C(Eu)≤6.10 -6 mol/L) and precipitation in COx water (C(Eu)≥6.10 -6 mol/L). Distribution coefficient Rd (quantifying sorption) was estimated at 170 ± 30 L/g. This high value is consistent with literature values obtained on clay rocks. The ternary Eu-OM-CR system study showed a slight increase of sorption in the presence of organic matter. This synergistic effect is very satisfactory in terms of storage security: the presence of small organic acids in clay rock does not question retention properties with respect to europium and trivalent actinides. (author)

238U-series radionuclides in Finnish groundwater-based drinking water and effective doses

International Nuclear Information System (INIS)

Vesterbacka, P.

2005-09-01

The thesis deals with the occurrence of 238 U-series radionuclides and particle-bound 210 Pb and 210 Po in Finnish groundwater-based drinking water, methods used for removing 234 U, 238 U, 210 Pb and 210 Po, and the annual effective doses caused by 238 U-series radionuclides in drinking water. In order to reduce radiation exposure and avoid high doses, it is important to examine the activity levels of natural radionuclides in groundwater. In this work, the activity concentrations of radon ( 222 Rn), radium ( 226 Ra), uranium ( 238 U and 234 U), lead ( 210 Pb) and polonium ( 210 Po) were determined from 472 private wells, which were selected randomly from across Finland. On the basis of the results, the activity concentrations in groundwater and the radiation exposure from drinking water of people living outside the public water supply in Finland was specified. The efficiency of 238 U, 234 U, 210 Pb and 210 Po removal from drinking water was examined at ten private homes. In order to obtain accurate results and correct estimates of effective doses, attention was paid to the sampling of 222 Rn and 210 Pb, and the determination of 210 Pb. The results revealed that the median activity concentrations of natural radionuclides were as much as ten times higher in drilled wells than in wells dug in soil. The average activity concentration of 222 Rn in drilled wells was 460 Bq/l and in dug wells 50 Bq/l. The highest activity concentrations were found in Southern Finland. In addition, occasional high activity concentrations were found all over Finland. The average activity concentrations of 234 U and 238 U in drilled wells were 0.35 and 0.26 Bq/l and in dug wells 0.020 and 0.015 Bq/l, respectively. The spatial distribution of 234 U, 238 U, 210 Pb and 210 Po was essentially similar to that of 222 Rn. In contrast to other natural radionuclides, the highest 226 Ra activity concentrations were found in coastal areas, since drilled well water near the sea has a higher salinity

Studies of decontamination using easy removable coatings technique

International Nuclear Information System (INIS)

Oglaza, J.; Nowak, Z.

1991-01-01

The usefulness of removable coatings for decontamination of steel and epoxy-resin painted surfaces was examined. Natural latex, Revultex, butadiene-styrene latex as well as mixtures of latex with complexing agents and surfactants were used as decontaminating coats. The best decontamination was obtained by removable coatings of natural latex with EDTA additive for all surfaces and radionuclides tested. (author). 16 refs, 5 tabs

Red light emission from europium doped zinc sodium bismuth borate glasses

Science.gov (United States)

Hegde, Vinod; Viswanath, C. S. Dwaraka; Upadhyaya, Vyasa; Mahato, K. K.; Kamath, Sudha D.

2017-12-01

Zinc sodium bismuth borate (ZNBB) glasses doped with different concentrations of europium were prepared by conventional melt quenching method and characterized through the measurements of density, refractive index, X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectra, optical absorption, luminescence and radiative lifetimes. FTIR spectra showed seven characteristic peaks of bismuth and borate functional groups in the range of 400-1600 cm-1. The optical band gap and bonding parameters have been calculated from absorption spectra. Photoluminescence spectra recorded in the visible region with 394 nm excitation are used to calculate the Judd-Ofelt (JO) intensity parameters (Ω2 and Ω4). The JO intensity parameters have been used to calculate the radiative parameters such as branching ratio (β), stimulated emission cross-section (σse), transition probability (A) for the fluorescent level of 5D0→7F2. Decay rates through single exponential are used to calculate the lifetime (τm) of the meta-stable state 5D0 of (Eu3+ ion) these glasses. The radiative parameters measured for all these glasses show 0.7 mol% europium doped zinc sodium bismuth borate glass 5D0→7F2 transition has the potential for red laser applications. The quality of the colour emitted by the present glasses are estimated quantitatively by CIE chromaticity coordinates, which confirms the suitability of these glasses as a red emitting material for field emission technologies and LEDs.

A Smart Europium-Ruthenium Complex as Anticancer Prodrug: Controllable Drug Release and Real-Time Monitoring under Different Light Excitations.

Science.gov (United States)

Li, Hongguang; Xie, Chen; Lan, Rongfeng; Zha, Shuai; Chan, Chi-Fai; Wong, Wing-Yan; Ho, Ka-Lok; Chan, Brandon Dow; Luo, Yuxia; Zhang, Jing-Xiang; Law, Ga-Lai; Tai, William C S; Bünzli, Jean-Claude G; Wong, Ka-Leung

2017-11-09

A unique, dual-function, photoactivatable anticancer prodrug, RuEuL, has been tailored that features a ruthenium(II) complex linked to a cyclen-europium chelate via a π-conjugated bridge. Under irradiation at 488 nm, the dark-inactive prodrug undergoes photodissociation, releasing the DNA-damaging ruthenium species. Under evaluation-window irradiation (λ irr = one-photon 350 nm or two-photon 700 nm), the drug delivery process can be quantitatively monitored in real-time because of the long-lived red europium emission. Linear relationships between released drug concentration and ESI-MS or luminescence responses are established. Finally, the efficiency of the new prodrug is demonstrated both in vitro RuEuL anticancer prodrug over some existing ones and open the way for decisive improvements in multipurpose prodrugs.

Radionuclide trap

International Nuclear Information System (INIS)

McGuire, J.C.

1978-01-01

The deposition of radionuclides manganese-54, cobalt-58 and cobalt-60 from liquid sodium coolant is controlled by providing surfaces of nickel or high nickel alloys to extract the radionuclides from the liquid sodium, and by providing surfaces of tungsten, molybdenum or tantalum to prevent or retard radionuclide deposition

Different-ligand coordination europium compounds with dibenzoylmethane, nitrate-group, and hexamethylphosphotriamide

International Nuclear Information System (INIS)

Karasev, V.E.; Botova, I.N.

1988-01-01

Some different-ligand europium complexes with dibenzoylmethane (DBM), hexamethylphosphotriamide (HMPA) and NO 3 -group of composition: Eu(NO 3 ) 3 x3HMPAx2H 2 O, Eu(NO 3 ) 2 xDBMx2HMPA, EuNO 3 x(DBM) 2 x2HMPA and Eu(DBM) 3 xHMPA are synthesized. Individuality of each complex is confirmed by methods of chemical, IR spectroscopic, luminescent, thermogravimetric analyses. Integral intensities of luminescence of synthesized complexes are measured, their excitation spectra in the crystal state at 77 K in the 200-600 nm range are studied

Chemical Studies on the treatment and Conditioning of Radioactive Liquid Waste Using Combined Processes

International Nuclear Information System (INIS)

El-Masry, E.H.

2004-01-01

Natural inorganic exchanges were used to remove radioactive isotopes cesium, Cobalt and europium using coagulant zinc sulfate as coagulant from low level liquid radioactive waste. the highest percent of removal was obtained in the order asswanlly (85.5%), bentonite (82.2%) and sandstone (65.4%) for the removal of cesium . the same order of removal percent was detected for the removal of cobalt (92.5,91.2,90.6%) and europium (90.6,90.8,90.2%) for asswanlly, bentonite and sandstone respectively

Rapid screening of oxytetracycline residue in catfish muscle by dispersive liquid-liquid microextraction and europium-sensitized luminescence

Science.gov (United States)

Oxytetracycline (OTC) residue in catfish muscle was screened by dispersive liquid-liquid microextraction (DLLME) and europium-sensitized luminescence (ESL). After extraction in EDTA, HCl, and acetonitrile, cleanup was carried out by DLLME, and ESL was measured at microgram = 385 nm and wavelength = ...

Evaluation and selection of aqueous-based technology for partitioning radionuclides from ICPP calcine

International Nuclear Information System (INIS)

Olson, A.L.; Schulz, W.W.; Burchfield, L.A.; Carlson, C.D.; Swanson, J.L.; Thompson, M.C.

1993-02-01

Early in 1993 Westinghouse Idaho Nuclear Company (WINCO) chartered a Panel of Nuclear Separations Experts. The purpose of this Panel was to assist WINCO scientists and engineers in selecting, evaluating, and ranking candidate aqueous-based processes and technologies for potential use in partitioning selected radionuclides from nitric acid solutions of retrieved Idaho Chemical Processing Plant (ICPP) calcine. Radionuclides of interest are all transuranium elements, 90 Sr, 99 Tc, 129 I, and 137 Cs. The six man Panel met for 4 days (February 16--19, 1993) on the campus of the Idaho State University in Pocatello, Idaho. Principal topics addressed included: Available radionuclide removal technology; applicability of separations technology and processes to ICPP calcine; and potential integrated radionuclide partitioning schemes. This report, prepared from contributions from all Panel members, presents a comprehensive account of the proceedings and significant findings of the February, 1993 meeting in Pocatello

Influence of biofilms on migration of uranium, americium and europium in the environment; Einfluss von Biofilmen auf das Migrationsverhalten von Uran, Americium und Europium in der Umwelt

Energy Technology Data Exchange (ETDEWEB)

Baumann, Nils; Zirnstein, Isabel; Arnold, Thuro

2015-07-01

The report on the influence of biofilms on migration of uranium, americium and europium in the environment deals with the contamination problems of uranium mines such as SDAG WISMUT in Saxonia and Thuringia. In mine waters microorganisms form a complex microbiological biocoenosis in spite of low pH values and high heavy metal concentrations including high uranium concentrations. The analyses used microbiological methods like confocal laser scanning microscopy and molecular-biological techniques. The interactions of microorganism with fluorescent radioactive heavy metal ions were performed with TRLFS (time resolved laser-induced fluorescence spectroscopy).

Luminescence variations in europium-doped silicon-substituted hydroxyapatite nanobiophosphor via three different methods

Energy Technology Data Exchange (ETDEWEB)

Thang, Cao Xuan; Pham, Vuong-Hung, E-mail: vuong.phamhung@hust.edu.vn

2015-07-15

Highlights: • Europium doped silicon-substituted hydroxyapatite was synthesized by wet chemical synthesis method. • Morphology of nanoparticles depended on the synthesized method. • Photoluminescence intensity of the sample increases with the increasing of Si substitutions, Eu dopants and thermal annealing. - Abstract: This paper reports the first attempt for the synthesis of europium-doped Si-substituted hydroxyapatite (HA) nanostructure to achieve strong and stable luminescence of nanobiophosphor, particularly, by addition of different Eu dopants, Si substitutions, and application of optimum annealing temperatures of up to 1000 °C. The nanobiophosphor was synthesized by the coprecipitation, microwave, and hydrothermal methods. The nanoparticles demonstrated a nanowire to a spindle-like morphology, which was dependent on the method of synthesis. The photoluminescence (PL) intensity of the sample increases with the increase in Si substitutions and Eu dopants. The luminescent nanoparticles also showed the typical luminescence of Eu{sup 3+} centered at 610 nm, which was more efficient for the annealed Eu-doped Si-HA nanoparticles than for the as-synthesized nanoparticles. Among the different synthesis methods, the hydrothermal method reveals the best light emission represented by high PL intensity and narrow PL spectra. These results suggest the potential application of Eu-doped Si-HA in stable and biocompatible nanophosphors for light emission and nanomedicine.

The europium(II) oxide halides Eu{sub 2}OBr{sub 2} and Eu{sub 2}OI{sub 2}; Die Europium(II)-Oxidhalogenide Eu{sub 2}OBr{sub 2} und Eu{sub 2}OI{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Rudolph, Daniel; Schleid, Thomas [Stuttgart Univ. (Germany). Inst. fuer Anorganische Chemie

2017-07-01

The syntheses and crystal structures of the two isotypic europium(II) oxide halides Eu{sub 2}OBr{sub 2} and Eu{sub 2}OI{sub 2} are reported. They crystallize orthorhombically in the space group Ibam (Z=4; Eu{sub 2}OBr{sub 2}: a=709.86(5), b=1200.34(9), c=628.71(4) pm; Eu{sub 2}OI{sub 2}: a=739.78(5), b=1295.13(9), c=644.82(4) pm). The unit cell parameters presented here, and thus the interatomic distances of Eu{sub 2}OI{sub 2}, are significantly smaller than the ones reported in the literature, which is explained by the substitution of europium with larger barium cations due to the synthesis route described in the early study. Central building blocks of both crystal structures are trans-edge-connected [OEu{sub 4}]{sup 6+} tetrahedra forming straight {sup 1}{sub ∞}{[OEu"e_4_/_2]"2"+} chains running parallel to the [001] direction. Bundled like a hexagonal rod packing, their interaction is achieved by Br{sup -} or I{sup -} anions for charge compensation.

Radiation, radionuclides and bacteria: An in-perspective review.

Science.gov (United States)

Shukla, Arpit; Parmar, Paritosh; Saraf, Meenu

2017-12-01

There has been a significant surge in consumption of radionuclides for various academic and commercial purposes. Correspondingly, there has been a considerable amount of generation of radioactive waste. Bacteria and archaea, being earliest inhabitants on earth serve as model microorganisms on earth. These microbes have consistently proven their mettle by surviving extreme environments, even extreme ionizing radiations. Their ability to accept and undergo stable genetic mutations have led to development of recombinant mutants that are been exploited for remediation of various pollutants such as; heavy metals, hydrocarbons and even radioactive waste (radwaste). Thus, microbes have repeatedly presented themselves to be prime candidates suitable for remediation of radwaste. It is interesting to study the behind-the-scenes interactions these microbes possess when observed in presence of radionuclides. The emphasis is on the indigenous bacteria isolated from radionuclide containing environments as well as the five fundamental interaction mechanisms that have been studied extensively, namely; bioaccumulation, biotransformation, biosorption, biosolubilisation and bioprecipitation. Application of microbes exhibiting such mechanisms in remediation of radioactive waste depends largely on the individual capability of the species. Challenges pertaining to its potential bioremediation activity is also been briefly discussed. This review provides an insight into the various mechanisms bacteria uses to tolerate, survive and carry out processes that could potentially lead the eco-friendly approach for removal of radionuclides. Copyright © 2017 Elsevier Ltd. All rights reserved.

First-Principles Investigations on Europium Monoxide

KAUST Repository

Wang, Hao

2011-05-01

Europium monoxide is both an insulator and a Heisenberg ferromagnet (Tc=69 K). In the present thesis, the author has investigated the electronic structure of different types of EuO by density functional theory. The on-site Coulomb interaction of the localized Eu 4f and 5d electrons, which is wrongly treated in the standard generalized gradient approximation method, is found to be crucial to obtain the correct insulating ground state as observed in experiments. Our results show that the ferromagnetism is stable under pressure, both hydrostatic and uniaxial. For both types of pressure an insulator-metal transition is demonstrated. Moreover, the experimentally observed insulator-metal transition in oxygen deficient and gadolinium-doped EuO is reproduced in our calculations for impurity concentrations of 6.25% and 25%. Furthermore, a 10- layer EuO thin film is theoretically predicted to be an insulator with a narrow band gap of around 0.08 eV, while the Si/EuO interface shows metallic properties with the Si and O 2p as well as Eu 5d bands crossing the Fermi level.

Radionuclide cisternography

International Nuclear Information System (INIS)

Song, H.H.

1980-01-01

The purpose of this thesis is to show that radionuclide cisternography makes an essential contribution to the investigation of cerebrospinal fluid (CSF) dynamics, especially for the investigation of hydrocephalus. The technical details of radionuclide cisternography are discussed, followed by a description of the normal and abnormal radionuclide cisternograms. The dynamics of CFS by means of radionuclide cisternography were examined in 188 patients in whom some kind of hydrocephalus was suspected. This study included findings of anomalies associated with hydrocephalus in a number of cases, such as nasal liquorrhea, hygromas, leptomeningeal or porencephalic cysts. The investigation substantiates the value of radionuclide cisternography in the diagnosis of disturbances of CSF flow. The retrograde flow of radiopharmaceutical into the ventricular system (ventricular reflux) is an abnormal phenomenon indicating the presence of communicating hydrocephalus. (Auth.)

Europium (III) PVC membrane sensor based on N-pyridine-2-carboxamido-8-aminoquinoline as a sensing material

International Nuclear Information System (INIS)

Zamani, Hassan Ali; Kamjoo, Rahman; Mohammadhosseini, Majid; Zaferoni, Mojdeh; Rafati, Zynab; Ganjali, Mohammad Reza; Faridbod, Farnoush; Meghdadi, Soraia

2012-01-01

Conductometric study in acetonitrile solution shows the selectivity of PCQ toward europium ion. Therefore, a new europium PVC membrane electrode was prepared based on N-pyridine-2-carboxamido-8-aminoquinoline (PCQ) as an ion carrier. The electrode has a wide concentration range from 1.0 × 10 −2 and 1.0 × 10 −6 mol L −1 , Nernstian slope of 19.8 ± 0.3 mV per decade and a detection limit of 6.4 × 10 −7 mol L −1 . The potentiometric response is pH independent in the range of 2.4–7.4. The proposed sensor has a relatively fast response time less than 10 s and it can be used for at least 2 months without any considerable divergence in its potentials. The proposed electrode revealed good selectivity toward europium ion in comparison with variety of other metal ions. The practical utility of the electrodes has been demonstrated by their use as indicator electrodes in the potentiometric titration of Eu 3+ ions with EDTA and for determination of Eu 3+ ion concentration in mixtures of two and three different ions. - Highlights: ► A new ion carrier is introduced to preparation of a selective sensor for Eu 3+ ions. ► This technique is very simple and it's not necessary to use sophisticated equipment. ► The novelty of this work is the high affinity of the ionophore toward the Eu 3+ ions. ► The sensor is superior to the formerly reported Eu 3+ sensors in terms of selectivity.

Application of a room temperature ionic liquid for nuclear spent fuel reprocessing: speciation of trivalent europium and solvatation effects; Application d'un liquide ionique basse temperature pour les procedes de separation: speciation de l'europium trivalent et effets solvatation

Energy Technology Data Exchange (ETDEWEB)

Moutiers, G.; Mekki, S. [CEA Saclay, Dept. de Physico-Chimie, Service de Chimie Physique, 91 - Gif sur Yvette (France); Billard, I. [IN2P3/CNRS, 69 - Villeurbanne (France)

2007-07-01

One of the solutions proposed for the optimization of the long term storage and conditioning of spent nuclear fuel is to separate actinide and lanthanide both from each other and from other less radioactive metallic species. The industrial proposed processes, based on liquid liquid extraction steps, involve solvents with non negligible vapour pressure and may generate contaminated liquid wastes that will have to be reprocessed. During the last decade, some room-temperature ionic liquids have been studied and integrated into industrial processes. The interest on this class of solvent came out from their 'green' properties (non volatile, non flammable, recyclable, etc...), but also from the variability of their physico-chemical properties (stability, hydrophobicity, viscosity) as a function of the RTIL chemical composition. Indeed, it has been shown that classical chemical industrial processes could be transferred into those media, even more improved, while a certain number of difficulties arising from using traditional solvent can be avoided. In this respect, it could be promising to investigate the ability to use room temperature ionic liquid into the spent nuclear fuel reprocessing field. The aim of this this study is to test the ability of the specific ionic liquid bumimTf{sub 2}N to allow trivalent europium extraction. The choice of this metal is based on the chemical analogy with trivalent minor actinides Curium and Americium which are contributing the greatest part of the long-lived high level radioactive wastes. Handling these elements needs to be very cautious for the safety and radioprotection aspect. Moreover, europium is a very sensitive luminescent probe to its environment even at the microscopic scale. The report is structured with four parts. In a first chapter, we present the main physico-chemical properties of an imidazolium-based ionic liquid family, and then we choose the ionic liquid bumimTf{sub 2}N for the whole thesis and start with

Proposed development of a radionuclide washoff model for the German Reactor Safety Study

International Nuclear Information System (INIS)

Helton, J.C.

1982-11-01

This report presents a brief overview of the possible development of a model for the attenuation of radionuclide concentrations in urban environments due to rainfall/runoff relationships. The following sequence of actions is suggested: (1) preliminary review, (2) exploratory modeling, (3) detailed literature review, (4) development of mathematical model, (5) development of computer model, and (6) model review including verification and sensitivity analysis. To facilitate the initiation of the indicated efforts, an introduction to the relevant literature is provided. Further, the following topics are also briefly discussed: (1) radionuclide transport and removal in the terrestrial environment, (2) need for a description of the chemical and physical forms of the radionuclides released in a reactor accident, and (3) potential importance of surface-water contamination. (orig./HP) [de

Decontamination of spent ion-exchangers contaminated with cesium radionuclides using resorcinol-formaldehyde resins.

Science.gov (United States)

Palamarchuk, Marina; Egorin, Andrey; Tokar, Eduard; Tutov, Mikhail; Marinin, Dmitry; Avramenko, Valentin

2017-01-05

The origin of the emergence of radioactive contamination not removable in the process of acid-base regeneration of ion-exchange resins used in treatment of technological media and liquid radioactive waste streams has been determined. It has been shown that a majority of cesium radionuclides not removable by regeneration are bound to inorganic deposits on the surface and inside the ion-exchange resin beads. The nature of the above inorganic inclusions has been investigated by means of the methods of electron microscopy, IR spectrometry and X-ray diffraction. The method of decontamination of spent ion-exchange resins and zeolites contaminated with cesium radionuclides employing selective resorcinol-formaldehyde resins has been suggested. Good prospects of such an approach in deep decontamination of spent ion exchangers have been demonstrated. Copyright © 2016 Elsevier B.V. All rights reserved.

Activity measurement of 33P and 32P radionuclide mixture

International Nuclear Information System (INIS)

Hanker, I.; Kansky, Z.

1984-01-01

The possibilities are briefly summed up of measuring mixtures of 33 P and 32 P with special regard to the method of simultaneous determination of both radionuclides in a liquid scintillator. This method was experimentally tested for special detection sensitivity and intended special applications in plant physiology and biochemistry using a dioxane scintillator (SLD-31, Spolana Neratovice, CSSR) and a Packard Tri-Carb 300 C, USA. The method gave erroneous results. The main cause of the errors in measurements of the 33 P and 32 P mixture in the SLD-31 was the adsorption of radionuclides on the inner wall of glass tubes. This phenomenon is not accompanied by changes in the quenching index. However, the effectiveness of measurement dropped and the relative contribution of the spectra of the two radionuclides changed with the time following sample preparation. The said effects were removed by adding 0.4% silicon dioxide (Cab-O-Sil M5, Serva) to the liquid scintillator. (author)

Application of a room temperature ionic liquid for nuclear spent fuel reprocessing: speciation of trivalent europium and solvatation effects

International Nuclear Information System (INIS)

Moutiers, G.; Mekki, S.; Billard, I.

2007-01-01

One of the solutions proposed for the optimization of the long term storage and conditioning of spent nuclear fuel is to separate actinide and lanthanide both from each other and from other less radioactive metallic species. The industrial proposed processes, based on liquid liquid extraction steps, involve solvents with non negligible vapour pressure and may generate contaminated liquid wastes that will have to be reprocessed. During the last decade, some room-temperature ionic liquids have been studied and integrated into industrial processes. The interest on this class of solvent came out from their 'green' properties (non volatile, non flammable, recyclable, etc...), but also from the variability of their physico-chemical properties (stability, hydrophobicity, viscosity) as a function of the RTIL chemical composition. Indeed, it has been shown that classical chemical industrial processes could be transferred into those media, even more improved, while a certain number of difficulties arising from using traditional solvent can be avoided. In this respect, it could be promising to investigate the ability to use room temperature ionic liquid into the spent nuclear fuel reprocessing field. The aim of this this study is to test the ability of the specific ionic liquid bumimTf 2 N to allow trivalent europium extraction. The choice of this metal is based on the chemical analogy with trivalent minor actinides Curium and Americium which are contributing the greatest part of the long-lived high level radioactive wastes. Handling these elements needs to be very cautious for the safety and radioprotection aspect. Moreover, europium is a very sensitive luminescent probe to its environment even at the microscopic scale. The report is structured with four parts. In a first chapter, we present the main physico-chemical properties of an imidazolium-based ionic liquid family, and then we choose the ionic liquid bumimTf 2 N for the whole thesis and start with the electrochemical

Marine sediments as a sink, and contaminated sediments as a diffuse source of radionuclides

International Nuclear Information System (INIS)

Salbu, B.; Borretzen, P.

1997-01-01

Full text: Marine sediments may act as a sink for radionuclides originating from atmospheric fallout (e.g. Chernobyl accident), for radionuclides in discharges from nuclear installations (e.g. Sellafield, UK) for river transported radionuclides, and radionuclides released from nuclear waste dumped at sea (e.g. fjords at Novaya Zemlya). In order to assess short and long term consequences of radionuclides entering the marine ecosystem, the role of sediments as a relatively permanent sink and the potential for contaminated sediments to act as a diffuse source should be focused. The retention of radionuclides in sediments will depend on the source term, i.e. the physico-chemical forms of radionuclides entering the system and on interactions with various sediment components. Radionuclides associated with particles or aggregating polymers are removed from the water phase by sedimentation, while sorption to surface sediment layers is of relevance for ionic radionuclide species including negatively charged colloids. With time, transformation processes will influence the mobility of radionuclides in sediments. The diffusion into mineral lattices will increase fixation, while the influence of for instance red/ox conditions and bio-erosion may mobilize radionuclides originally fixed in radioactive particles. Thus, information of radionuclides species, surface interactions, transformation processes and kinetics is essential for reducing the uncertainties in marine transfer models. Dynamic model experiments where chemically well defined tracers are added to a sea water-marine sediment system are useful for providing information on time dependent interactions and distribution coefficients. When combined with sequential extraction techniques, information on mobility and rate of fixation is subsequently attained. In the present work experimental results from the Irish Sea and the Kara Sea will be discussed

Chloride, bromide and iodide scintillators with europium

Science.gov (United States)

Zhuravleva, Mariya; Yang, Kan

2016-09-27

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

Uptake of Radionuclide Metals by SPME Fibers

International Nuclear Information System (INIS)

Duff, M; S Crump, S; Robert Ray, R; Keisha Martin, K; Donna Beals, D

2006-08-01

The Federal Bureau of Investigation (FBI) Laboratory currently does not have on site facilities for handling radioactive evidentiary materials and there are no established FBI methods or procedures for decontaminating high explosive (HE) and fire debris (FD) evidence while maintaining evidentiary value. One experimental method for the isolation of HE and FD residue involves using solid phase microextraction or SPME fibers to remove residue of interest. Due to their high affinity for organics, SPME fibers should have little affinity for most metals. However, no studies have measured the affinity of radionuclides for SPME fibers. The focus of this research was to examine the affinity of dissolved radionuclide ( 239/240 Pu, 238 U, 237 Np, 85 Sr, 133 Ba, 137 Cs, 60 Co and 226 Ra) and stable radionuclide surrogate metals (Sr, Co, Ir, Re, Ni, Ba, Cs, Nb, Zr, Ru, and Nd) for SPME fibers at the exposure conditions that favor the uptake of HE and FD residues. Our results from radiochemical and mass spectrometric analyses indicate these metals have little measurable affinity for these SPME fibers during conditions that are conducive to HE and FD residue uptake with subsequent analysis by liquid or gas phase chromatography with mass spectrometric detection

Surface-imprinted nanofilaments for europium-amplified luminescent detection of fluoroquinolone antibiotics.

Science.gov (United States)

Zdunek, Jolanta; Benito-Peña, Elena; Linares, Ana; Falcimaigne-Cordin, Aude; Orellana, Guillermo; Haupt, Karsten; Moreno-Bondi, María C

2013-07-29

The development and characterization of novel, molecularly imprinted polymer nanofilament-based optical sensors for the analysis of enrofloxacin, an antibiotic widely used for human and veterinary applications, is reported. The polymers were prepared by nanomolding in porous alumina by using enrofloxacin as the template. The antibiotic was covalently immobilized on to the pore walls of the alumina by using different spacers, and the prepolymerization mixture was cast in the pores and the polymer synthesized anchored onto a glass support through UV polymerization. Various parameters affecting polymer selectivity were evaluated to achieve optimal recognition, namely, the spacer arm length and the binding solvent. The results of morphological characterization, binding kinetics, and selectivity of the optimized polymer material for ENR and its derivatives are reported. For sensing purposes, the nanofilaments were incubated in solutions of the target molecule in acetonitrile/HEPES buffer (100 mM, pH 7.5, 50:50, v/v) for 20 min followed by incubation in a 10 mM solution of europium(III) ions to generate a europium(III)-enrofloxacin complex on the polymer surface. The detection event was based on the luminescence of the rare-earth ion (λexc=340 nm; λem=612 nm) that results from energy transfer from the antibiotic excited state to the metal-ion emitting excited state. The limit of detection of the enrofloxacin antibiotic was found to be 0.58 μM. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Radionuclide and heavy metal biosorption by Pseudomonas biomass

International Nuclear Information System (INIS)

Sar, Pinaki; D'Souza, S.F.; Kazy, Sufia K.; Singh, S.P.

2001-01-01

Biosorptive metal (nickel and copper) and radionuclide (uranium) uptake capacity of two Pseudomonas strains was investigated in order to develop biotechnological strategies for toxic metals remediation. Lyophilized Pseudomonas biomass showed a very high uranium loading of 541 mg g -1 dry wt. Compared to this, the other bacterial strain of Pseudomonas aeruginosa used for nickel and copper removal yielded a maximum value of 265 mg g -1 and 137 mg g -1 respectively. Cation binding by both the biomass was fast saturating, pH -dependent process with optimum pH for U, Cu and Ni was pH 5.0, 7.0 and 8.0, respectively. In bimetallic combination, U sorption was inhibited only by Fe 3+ , Al 3+ and Cu 2+ suggesting a selective cation binding by the Pseudomonas biomass. In case of Ni and Cu, presence of Na, K or Ca increased the metal binding while Cd and Pb was antagonistic. Mineral acids could recover more than 75% (on average) of sorbed Ni or Cu. Noticeably, uranium and copper desorption was specifically high (88-90%) with sodium carbonate while calcium carbonate showed a good result for nickel. The overall data are in favour of deployment of the test biomass as efficient metal/radionuclide removal/recovery system. (author)

Preparation of 1 Ci of europium 155 without carrier

International Nuclear Information System (INIS)

Falconi, N.; Radicella, R.

1968-01-01

High activity 'point' sources of 155 Eu are used for medical and industrial applications. For this purpose we have studied a method of obtaining I Ci of carrier free 155 Eu, with a solid residue smaller than 5 mg per Ci. In order to separate the 155 Eu from several grams of a 154 Sm enriched target we propose a procedure which is based on the work of Bouissieres and David, Onstott, and Takekoshi et al. The separation is carried out by electrolysis on a mercury cathode followed by purification on ion exchange resin. The yields of the europium separation and target recovery are 80 per cent and 90 per cent respectively. The time required for the procedure is three days. (authors) [fr

Removal of radon by aeration testing of various aeration techniques for small water works. For European Commission under Contract No FI4PCT960054 TENAWA project

CERN Document Server

Salonen, L; Mehtonen, J; Mjoenes, L; Raff, O; Turunen, H

2002-01-01

Capability of various aeration techniques to remove radon from water in small waterworks was studied as a part of project (Treatment Techniques for Removing Natural Radionuclides from Drinking Water), which was carried out during 1997-1999 on a cost-shared basis (contract No. F14PCT960054) with The European Commission (CEC) under the supervision of the Directorate-General XII Radiation Protection Research Unit. In TENAWA project both laboratory and field experiments were performed in order to find reliable methods and equipment for removing natural radionuclides from ground water originating either from private wells or small waterworks. Because such techniques are more often needed in private households than at waterworks, the main emphasis of the research was aimed to solve the water treatment problems related to the private water supplies, especially bedrock wells. Radon was the most important radionuclide to be removed from water at waterworks whereas the removal of other radionuclides ( sup 2 sup 3 sup 4...

Naturally occurring radionuclides in drinking water before and after radon removal

International Nuclear Information System (INIS)

Swedjemark, G.A.; Linden, A.

1998-06-01

Radon removal can, with a good effect, be used to remove radon from well water. The short-lived radon progeny have been investigated in the raw and cleaned water from six private wells where radon removal based on aeration and recirculation of the water have been installed. The results from this pilot study indicate that the short-lived radon progeny in some cases follow the water to the tap for consumption to such an extent that the problem should be considered. The extent of the study is not sufficient for general conclusions. However, it is important to stress that the effective dose from the short-lived progeny is always lower than it would have been from the radon, when no radon is removed

A microwave-assisted solution combustion synthesis to produce europium-doped calcium phosphate nanowhiskers for bioimaging applications.

Science.gov (United States)

Wagner, Darcy E; Eisenmann, Kathryn M; Nestor-Kalinoski, Andrea L; Bhaduri, Sarit B

2013-09-01

Biocompatible nanoparticles possessing fluorescent properties offer attractive possibilities for multifunctional bioimaging and/or drug and gene delivery applications. Many of the limitations with current imaging systems center on the properties of the optical probes in relation to equipment technical capabilities. Here we introduce a novel high aspect ratio and highly crystalline europium-doped calcium phosphate nanowhisker produced using a simple microwave-assisted solution combustion synthesis method for use as a multifunctional bioimaging probe. X-ray diffraction confirmed the material phase as europium-doped hydroxyapatite. Fluorescence emission and excitation spectra and their corresponding peaks were identified using spectrofluorimetry and validated with fluorescence, confocal and multiphoton microscopy. The nanowhiskers were found to exhibit red and far red wavelength fluorescence under ultraviolet excitation with an optimal peak emission of 696 nm achieved with a 350 nm excitation. Relatively narrow emission bands were observed, which may permit their use in multicolor imaging applications. Confocal and multiphoton microscopy confirmed that the nanoparticles provide sufficient intensity to be utilized in imaging applications. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Highly Sensitive Luminescence Assessment of Bile Acid Using a Balofloxacin-Europium(III) Probe in Micellar Medium

International Nuclear Information System (INIS)

Cai, Huan; Zhao, Fang; Si, Hailin; Zhang, Shuaishuai; Wang, Chunchun; Qi, Peirong

2012-01-01

A novel and simple method of luminescence enhancement effect for the determination of trace amounts of bile acid was proposed. The procedure was based on the luminescence intensity of the balofloxacin-europium(III) complex that could be strongly enhanced by bile acid in the presence of sodium dodecyl benzene sulfonate (SDBS). Under the optimum conditions, the enhanced luminescence intensity of the system exhibited a good linear relationship with the bile acid concentration in the range 5.0 Χ 10 -9 - 7.0 Χ 10 -7 mol L -1 with a detection limit of 1.3 Χ 10 -9 mol L.1 (3σ). The relative standard deviation (RSD) was 1.7% (n = 11) for 5.0 Χ 10 -8 mol L -1 bile acid. The applicability of the method to the determination of bile acid was demonstrated by investigating the effect of potential interferences and by analyzing human serum and urine samples. The possible enhancement mechanism of luminescence intensity in balofloxacin-europium(III)-bile acid-SDBS system was also discussed briefly

Europium (III) PVC membrane sensor based on N-pyridine-2-carboxamido-8-aminoquinoline as a sensing material

Energy Technology Data Exchange (ETDEWEB)

Zamani, Hassan Ali, E-mail: haszamani@yahoo.com [Department of Applied Chemistry, Quchan branch, Islamic Azad University, Quchan (Iran, Islamic Republic of); Kamjoo, Rahman [Department of Applied Chemistry, Quchan branch, Islamic Azad University, Quchan (Iran, Islamic Republic of); Mohammadhosseini, Majid [Department of Chemistry, Faculty of Basic Sciences, Shahrood Branch, Islamic Azad University, Shahrood (Iran, Islamic Republic of); Zaferoni, Mojdeh; Rafati, Zynab [Department of Applied Chemistry, Quchan branch, Islamic Azad University, Quchan (Iran, Islamic Republic of); Ganjali, Mohammad Reza [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Faridbod, Farnoush [Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Meghdadi, Soraia [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

2012-04-01

Conductometric study in acetonitrile solution shows the selectivity of PCQ toward europium ion. Therefore, a new europium PVC membrane electrode was prepared based on N-pyridine-2-carboxamido-8-aminoquinoline (PCQ) as an ion carrier. The electrode has a wide concentration range from 1.0 Multiplication-Sign 10{sup -2} and 1.0 Multiplication-Sign 10{sup -6} mol L{sup -1}, Nernstian slope of 19.8 {+-} 0.3 mV per decade and a detection limit of 6.4 Multiplication-Sign 10{sup -7} mol L{sup -1}. The potentiometric response is pH independent in the range of 2.4-7.4. The proposed sensor has a relatively fast response time less than 10 s and it can be used for at least 2 months without any considerable divergence in its potentials. The proposed electrode revealed good selectivity toward europium ion in comparison with variety of other metal ions. The practical utility of the electrodes has been demonstrated by their use as indicator electrodes in the potentiometric titration of Eu{sup 3+} ions with EDTA and for determination of Eu{sup 3+} ion concentration in mixtures of two and three different ions. - Highlights: Black-Right-Pointing-Pointer A new ion carrier is introduced to preparation of a selective sensor for Eu{sup 3+} ions. Black-Right-Pointing-Pointer This technique is very simple and it's not necessary to use sophisticated equipment. Black-Right-Pointing-Pointer The novelty of this work is the high affinity of the ionophore toward the Eu{sup 3+} ions. Black-Right-Pointing-Pointer The sensor is superior to the formerly reported Eu{sup 3+} sensors in terms of selectivity.

Derived intervention levels for radionuclides in food

International Nuclear Information System (INIS)

1988-01-01

After the nuclear accident at Chernobyl in 1986, many countries were affected by widespread radioactive contamination. It became clear that the available guidance on dealing with the consequences of a nuclear accident was inappropriate for the long term and for areas far removed from the accident site. A particular concern was the safety of radioactively contaminated food and drinking-water in the ''far field'' region. The present guidelines, based on health protection principles, have been prepared by the World Health Organization in response to this concern. For various food categories, recommendations are made on levels of contamination by radionuclides at which corrective action might be justified to reduce the health risk to the population. The guidelines are based on accepted radiation dose criteria, on food consumption data from different parts of the world, and on dosimetric information for the relevant radionuclides. They are intended to assist in national decision-making in the event of another major nuclear accident. Refs, 1 fig., 14 tabs

Determination for Enterobacter cloacae based on a europium ternary complex labeled DNA probe

Science.gov (United States)

He, Hui; Niu, Cheng-Gang; Zeng, Guang-Ming; Ruan, Min; Qin, Pin-Zhu; Liu, Jing

2011-11-01

The fast detection and accurate diagnosis of the prevalent pathogenic bacteria is very important for the treatment of disease. Nowadays, fluorescence techniques are important tools for diagnosis. A two-probe tandem DNA hybridization assay was designed for the detection of Enterobacter cloacae based on time-resolved fluorescence. In this work, the authors synthesized a novel europium ternary complex Eu(TTA) 3(5-NH 2-phen) with intense luminescence, high fluorescence quantum yield and long lifetime before. We developed a method based on this europium complex for the specific detection of original extracted DNA from E. cloacae. In the hybridization assay format, the reporter probe was labeled with Eu(TTA) 3(5-NH 2-phen) on the 5'-terminus, and the capture probe capture probe was covalent immobilized on the surface of the glutaraldehyde treated glass slides. The original extracted DNA of samples was directly used without any DNA purification and amplification. The detection was conducted by monitoring the fluorescence intensity from the glass surface after DNA hybridization. The detection limit of the DNA was 5 × 10 -10 mol L -1. The results of the present work proved that this new approach was easy to operate with high sensitivity and specificity. It could be conducted as a powerful tool for the detection of pathogen microorganisms in the environment.

Speciation analysis of radionuclides

International Nuclear Information System (INIS)

Salbu, B.

2010-01-01

Full text: Naturally occurring and artificially produced radionuclides in the environment can be present in different physico-chemical forms (i. e. radionuclide species) varying in size (nominal molecular mass), charge properties and valence, oxidation state, structure and morphology, density, complexing ability etc. Low molecular mass (LMM) species are believed to be mobile and potentially bioavailable, while high molecular mass (HMM) species such as colloids, polymers, pseudocolloids and particles are considered inert. Due to time dependent transformation processes such as mobilization of radionuclide species from solid phases or interactions of mobile and reactive radionuclide species with components in soils and sediments, however, the original distribution of radionuclides deposited in ecosystems will change over time and influence the ecosystem behaviour. To assess the environmental impact from radionuclide contamination, information on radionuclide species deposited, interactions within affected ecosystems and the time-dependent distribution of radionuclide species influencing mobility and biological uptake is essential. The development of speciation techniques to characterize radionuclide species in waters, soils and sediments should therefore be essential for improving the prediction power of impact and risk assessment models. The present paper reviews fractionation techniques which should be utilised for radionuclide speciation purposes. (author)

Europium-doped amorphous calcium phosphate porous nanospheres: preparation and application as luminescent drug carriers

Directory of Open Access Journals (Sweden)

Zhang Kui-Hua

2011-01-01

Full Text Available Abstract Calcium phosphate is the most important inorganic constituent of biological tissues, and synthetic calcium phosphate has been widely used as biomaterials. In this study, a facile method has been developed for the fabrication of amorphous calcium phosphate (ACP/polylactide-block-monomethoxy(polyethyleneglycol hybrid nanoparticles and ACP porous nanospheres. Europium-doping is performed to enable photoluminescence (PL function of ACP porous nanospheres. A high specific surface area of the europium-doped ACP (Eu3+:ACP porous nanospheres is achieved (126.7 m2/g. PL properties of Eu3+:ACP porous nanospheres are investigated, and the most intense peak at 612 nm is observed at 5 mol% Eu3+ doping. In vitro cytotoxicity experiments indicate that the as-prepared Eu3+:ACP porous nanospheres are biocompatible. In vitro drug release experiments indicate that the ibuprofen-loaded Eu3+:ACP porous nanospheres show a slow and sustained drug release in simulated body fluid. We have found that the cumulative amount of released drug has a linear relationship with the natural logarithm of release time (ln(t. The Eu3+:ACP porous nanospheres are bioactive, and can transform to hydroxyapatite during drug release. The PL properties of drug-loaded nanocarriers before and after drug release are also investigated.

Synthesis and luminescence properties of europium and terbium complexes with pyridine- or bipyridine-linked oligothiophene ligand

International Nuclear Information System (INIS)

Liu Ping; Huang Mingsheng; Pan Wanzhang; Zhang Yamin; Hu Jianhua; Deng Wenji

2006-01-01

With an aim to develop novel luminescence materials, europium and terbium complexes of 2,5-(2-thiophene)-pyridine (TPY) and 5,5'-bis(5-(2,2'-bithiophene))-2,2'-bipyridine (B2TBPY) were synthesized, and their luminescence properties studied. The complexes exhibit ligand-sensitized emission, which is typical of Eu(III) and Tb(III) ions

Precipitation scavenging of 7Be and 137Cs radionuclides in air

International Nuclear Information System (INIS)

Ioannidou, A.; Papastefanou, C.

2006-01-01

Atmospheric depositional fluxes of the naturally occurring 7 Be of cosmogenic origin and 137 Cs from fallout of the Chernobyl accident were measured over a 6-year period (January 1987-December 1992) at Thessaloniki, Greece (40 o 38'N, 22 o 58'E). Total precipitation accumulation during 1987-1992 varied between 33.7 cm and 65.2 cm, reflecting a relatively dry (precipitation-free) climate. The activity concentrations of 7 Be and 137 Cs in rainwater depended on the precipitation rate, being higher for low precipitation rates and lesser for high precipitation rates. 137 Cs was removed by rain and snow more efficiently than 7 Be. Snowfall was more efficient than rainfall in removing the radionuclides from the atmosphere. The annual bulk depositional fluxes of 7 Be varied between 477 and 1133 Bq m -2 y -1 and this variability was attributed to the amount of precipitation and the variations of the atmospheric concentrations of 7 Be. The annual bulk depositional fluxes of 137 Cs showed a significant decrease over time from 1987 to 1992, resulting in a removal half-life of 1.33 years. The presence of 137 Cs in air, and therefore in rainwater and snow, long after the Chernobyl accident (26 April 1986) was mainly due to the resuspension process. The normalized depositional fluxes of both radionuclides showed maximal values during the spring season where the maximum amount of precipitation occurred. The relatively high positive correlation between 7 Be and 137 Cs normalized depositional fluxes indicates that the scavenging process of local precipitation controlled the fluxes of both radionuclides. The dry depositional flux of 7 Be was less than 9.37% of total (wet and dry) depositional flux. The fraction of dry-to-total depositional flux of 137 Cs was much higher than that of 7 Be, due to the resuspended soil

Quantitative radionuclide angiocardiography

International Nuclear Information System (INIS)

Scholz, P.M.; Rerych, S.K.; Moran, J.F.; Newman, G.E.; Douglas, J.M.; Sabiston, D.C. Jr.; Jones, R.H.

1980-01-01

This study introduces a new method for calculating actual left ventricular volumes and cardiac output from data recorded during a single transit of a radionuclide bolus through the heart, and describes in detail current radionuclide angiocardiography methodology. A group of 64 healthy adults with a wide age range were studied to define the normal range of hemodynamic parameters determined by the technique. Radionuclide angiocardiograms were performed in patients undergoing cardiac catherization to validate the measurements. In 33 patients studied by both techniques on the same day, a close correlation was documented for measurement of ejection fraction and end-diastolic volume. To validate the method of volumetric cardiac output calcuation, 33 simultaneous radionuclide and indocyanine green dye determinations of cardiac output were performed in 18 normal young adults. These independent comparisons of radionuclide measurements with two separate methods document that initial transit radionuclide angiocardiography accurately assesses left ventricular function

MATADOR (Methods for the Analysis of Transport And Deposition Of Radionuclides) code description and User's Manual

International Nuclear Information System (INIS)

Avci, H.I.; Raghuram, S.; Baybutt, P.

1985-04-01

A new computer code called MATADOR (Methods for the Analysis of Transport And Deposition Of Radionuclides) has been developed to replace the CORRAL-2 computer code which was written for the Reactor Safety Study (WASH-1400). This report is a User's Manual for MATADOR. MATADOR is intended for use in system risk studies to analyze radionuclide transport and deposition in reactor containments. The principal output of the code is information on the timing and magnitude of radionuclide releases to the environment as a result of severely degraded core accidents. MATADOR considers the transport of radionuclides through the containment and their removal by natural deposition and by engineered safety systems such as sprays. It is capable of analyzing the behavior of radionuclides existing either as vapors or aerosols in the containment. The code requires input data on the source terms into the containment, the geometry of the containment, and thermal-hydraulic conditions in the containment

Liquid crystal europium(III) β-diketonato complex with 5,5'-di(heptadecyl)-2,2'-bipyridine

International Nuclear Information System (INIS)

Knyazev, A.A.; Lobkov, V.S.; Galyametdinov, Yu.G.

2004-01-01

Liquid crystal europium(III) complex containing β-diketone and 5,5-di(heptadecyl)-2,2'-bipyridine as ligands was prepared in ethanol solution and was isolated as a yellow precipitate with 62% yield. The product was characterized by data of elementary analysis, thermography, IR spectroscopy and luminescence spectra. Temperatures of crystal-mesophase and mesophase-isotropic liquid phase transitions amount to 95 and 130 Deg C respectively [ru

Spectroscopic properties of trivalent Europium in various composites with an eulytin structure. Internship report

International Nuclear Information System (INIS)

Raynal, Francoise

1975-01-01

Eulytin is a bismuth orthosilicate and eulytin compounds revealed to be interesting matrix materials which can be used as medium gain laser materials. This research report is thus a contribution for a better knowledge of this material. Different eulytin compounds doped with lanthanide ions have been used to study the cationic polyhedron (by using structural probes such as the trivalent Europium in spectroscopy, or the trivalent gadolinium in electronic paramagnetic resonance) and the anionic polyhedron

Luminescent amine sensor based on europium(III) chelate.

Science.gov (United States)

Petrochenkova, Nataliya V; Mirochnik, Anatolii G; Emelina, Tatyana B; Sergeev, Alexander A; Leonov, Andrei A; Voznesenskii, Sergey S

2018-07-05

The effect of methylamine vapor on luminescence of Eu(III) tris-benzoylacetonate (I) immobilized in thin-layer chromatography plates has been investigated. It has been revealed that interaction of I with analyte vapor results in increase of the intensity of Eu(III) luminescence. The mechanism of the effect of methylamine vapors on intensification of the Eu(III) luminescence has been suggested using the data of IR spectroscopy and quantum chemistry calculations. The mechanism of luminescence sensitization consists in bonding of an analyte molecule with a water molecule into the coordination sphere of Eu(III). As a result, the bond of a water molecule with the luminescence centre weakens, rigid structural fragment including europium ion, water and methylamine molecules forms. The presence of such fragment must naturally promote decrease of influence of OH-vibrations on luminescence of the complex I. Copyright © 2018 Elsevier B.V. All rights reserved.

The mercury-richest europium amalgam Eu{sub 10}Hg{sub 55}

Energy Technology Data Exchange (ETDEWEB)

Tambornino, Frank; Hoch, Constantin [Department of Chemistry, Ludwig-Maximilians-Universitaet Muenchen (Germany)

2015-03-15

The mercury-richest europium amalgam Eu{sub 10}Hg{sub 55} was synthesized by isothermal electrocrystallization from a solution of EuI{sub 3}.8DMF in DMF on a reactive mercury cathode. The crystal structure shows remarkable complexity and polar metal-metal bonding. Closely related to the structures of mercury-rich amalgams A{sub 11-x}Hg{sub 55+x} (A = Na, Ca, Sr), it shows underoccupied Hg positions along [00z]. Eu{sub 10}Hg{sub 55} can be described as hettotype structure of the Gd{sub 14}Ag{sub 51} structure type. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Positive parity states and some electromagnetic transition properties of even-odd europium isotopes

Energy Technology Data Exchange (ETDEWEB)

Yazar, Harun Resit, E-mail: yazar@nevsehir.edu.tr [Nevsehir University, Faculty of Art and Science (Turkey)

2013-06-15

The positive-parity low-spin states of even-odd Europium isotopes ({sup 151-155}Eu) were studied within the framework of the interacting boson-fermion model. The calculated positive low-spin state energy spectra of the odd Eu isotope were found to agree quite well with the experimental data. The B(E2) values were also calculated and it was found that the calculated positive-parity low-spin state energy spectra of the odd-A Eu isotopes agree quite well with the experimental data.

Investigation of the influence of silver and tin on the luminescence of trivalent europium ions in glass

International Nuclear Information System (INIS)

Jimenez, J.A.; Lysenko, S.; Liu, H.; Fachini, E.; Cabrera, C.R.

2010-01-01

Europium-doped aluminophosphate glasses prepared by the melt-quenching technique have been studied by photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS). The effects of silver and tin doping, and of further thermal processing on Eu 3+ ions luminescence have been assessed. For the glass system containing only europium, Eu 3+ PL observed under UV excitation is suggested to occur through energy transfer from the excited glass host. After silver and tin doping, an enhanced UV excited Eu 3+ PL has been indicated to occur essentially due to radiative energy transfer from isolated Ag + ions and/or two fold-coordinated Sn centers. Since thermal processing of the material leads to a quenching effect on Eu 3+ PL and Ag nanoparticles (NPs) formation due to reduction of silver ions by tin, XPS was employed in order to investigate the possibility for Eu 3+ →Eu 2+ reduction during HT as a potential source of the PL decrease. The data points towards Ag NPs as main responsible for the observed weakening of Eu 3+ PL.

Radionuclide fixation mechanisms in rocks

International Nuclear Information System (INIS)

Nakashima, S.

1991-01-01

In the safety evaluation of the radioactive waste disposal in geological environment, the mass balance equation for radionuclide migration is given. The sorption of radionuclides by geological formations is conventionally represented by the retardation of the radionuclides as compared with water movement. In order to quantify the sorption of radionuclides by rocks and sediments, the distribution ratio is used. In order to study quantitatively the long term behavior of waste radionuclides in geological environment, besides the distribution ratio concept in short term, slower radionuclide retention reaction involving mineral transformation should be considered. The development of microspectroscopic method for long term reaction path modeling, the behavior of iron during granite and water interaction, the reduction precipitation of radionuclides, radionuclide migration pathways, and the representative scheme of radionuclide migration and fixation in rocks are discussed. (K.I.)

Hot Spot Removal System: System description

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-09-01

Hazardous wastes contaminated with radionuclides, chemicals, and explosives exist across the Department of Energy complex and need to be remediated due to environmental concerns. Currently, an opportunity is being developed to dramatically reduce remediation costs and to assist in the acceleration of schedules associated with these wastes by deploying a Hot Spot Removal System. Removing the hot spot from the waste site will remove risk driver(s) and enable another, more cost effective process/option/remedial alternative (i.e., capping) to be applied to the remainder of the site. The Hot Spot Removal System consists of a suite of technologies that will be utilized to locate and remove source terms. Components of the system can also be used in a variety of other cleanup activities. This Hot Spot Removal System Description document presents technologies that were considered for possible inclusion in the Hot Spot Removal System, technologies made available to the Hot Spot Removal System, industrial interest in the Hot Spot Removal System`s subsystems, the schedule required for the Hot Spot Removal System, the evaluation of the relevant technologies, and the recommendations for equipment and technologies as stated in the Plan section.

Hot Spot Removal System: System description

International Nuclear Information System (INIS)

1997-09-01

Hazardous wastes contaminated with radionuclides, chemicals, and explosives exist across the Department of Energy complex and need to be remediated due to environmental concerns. Currently, an opportunity is being developed to dramatically reduce remediation costs and to assist in the acceleration of schedules associated with these wastes by deploying a Hot Spot Removal System. Removing the hot spot from the waste site will remove risk driver(s) and enable another, more cost effective process/option/remedial alternative (i.e., capping) to be applied to the remainder of the site. The Hot Spot Removal System consists of a suite of technologies that will be utilized to locate and remove source terms. Components of the system can also be used in a variety of other cleanup activities. This Hot Spot Removal System Description document presents technologies that were considered for possible inclusion in the Hot Spot Removal System, technologies made available to the Hot Spot Removal System, industrial interest in the Hot Spot Removal System''s subsystems, the schedule required for the Hot Spot Removal System, the evaluation of the relevant technologies, and the recommendations for equipment and technologies as stated in the Plan section

Filters for water purification from radionuclides

International Nuclear Information System (INIS)

Mironov, V.V.; Khaydarov, R.R.; Khaydarov, R.A.; Gapurova, O.U.

2006-01-01

Full text: At present purification of waste water and drinking water from radionuclides, heavy metal ions, and organic contaminants is one of the most important problems. One of widely used methods for solving this problem is the ion exchange method based on using of different types of resins and fibroid sorbents. This paper deals with new chemically modified polyester fibroid filters having satisfactory adsorption characteristics. The process of the filter production includes their treatment by acrylonitrilic emulsion for improving mechanical characteristics. An advantage of the fibroid ion-exchange sorbents over resin is in their high sorption rate, effective regeneration and small value of pressure drop of the sorbent layer for purified water. The specific surface of the fibroid sorbents is (2 - 3). 10 4 m 2 / kg, i.e. about 10 2 times greater than that of the resin (10 2 m 2 / kg). Owing to that fact the rate of the sorption process on the developed fibroid sorbents is much greater than that on the resin. The developed cation- and anion-exchange filters can be used for removing metal ions (Zn, Ni, Cu, Sb, Co, Cd, Cr, etc.) and organic compounds (M- 32 P, M- 131 I, M- 99 Mo+ 99m Tc, etc.) from water. Capacity of the cation-exchange sorbents is 0.25 meq/g (Cu 2+ ) and that of the anion - exchange is 0.45 meq/g (Cr 6+ ). The cation- and anion-exchange filters are also selective for removing radionuclides 134 , 137 Cs, 90 Sr, 60 Co and 129 I in presence of Na + , K + , Ca 2+ , Mg 2+ , Cl - ions in water at concentrations up to 500 mg/L. New developed ion-exchange sorbents have been used in drinking water filters and mini-systems for removing organic and inorganic contaminants, in the equipment for waste water purification from oil products (at atomic power stations, car-washing stations, etc), from heavy metal ions (in electronic industry, match fabrics, leather processing plants etc). (author)

Radon removal from different types of groundwater applying granular activated carbon filtration

International Nuclear Information System (INIS)

Turtiainen, T.; Salonen, L.; Myllymaeki, P.

2000-01-01

Granular activated carbon (CAC) filters were installed in 12 private homes or vacation homes for removing unacceptably high concentrations of radon from household water. Radon removal efficiency was nearly 100% in most locations, although different water types were encountered. Other radionuclides such as uranium, radium, lead and polonium were removed less efficiently. Treated water quality remained good and no significant external radiation dose was caused to the residents. (author)

Spectroscopic studies of 2-thenoyltrifluoro acetonate of uranyl salts doped with europium

International Nuclear Information System (INIS)

Nakagawa, F.T.; Luiz, J.E.M. de Sa; Felinto, M.C.F.C.; Brito, H.F.; Teotonio, E.E.S.

2006-01-01

Uranyl compounds present a great potential as luminescence materials. Some examples of applications are: in laser technology, cathode ray tube, X-rays diagnostic. In this work it was studied the synthesis, characterization and spectroscopic properties study of uranyl 2-thenoyl trifluoroacetonate and uranyl 2- thenoyl trifluoroacetonate doped with europium. The compounds were synthesized and characterized by infrared absorption spectroscopy, thermal analysis, scanning electronic microscopy, and electronic spectroscopy of emission and excitation. The Eu 3+ ion acted as an effective luminescent probe, however the process of energy transfer from UO 2 2+ to Eu 3+ ion has not been efficient. (author)

Determination of micro amounts of samarium and europium by analogue derivative spectrophotometry

International Nuclear Information System (INIS)

Ishii, H.; Satoh, K.

1982-01-01

Derivative spectrophotometry using the analogue differentiation circuit was applied to the determination of samarium and europium at ppm levels. By measuring the second or the fourth derivative spectra of the characteristic absorption bands of both the rare earth ions around 400 nm, they can be determined directly and selectively in the presence of large amounts of most other rare earths without any prior separation. Further, aptly selecting conditions for the measurement of the derivative spectra, the simultaneous determination of both the rare earth elements was feasible. The principle and the characteristics of analogue derivative spectrophotometry are also described. (orig.) [de

Red polymer light-emitting devices based on an oxadiazole-functionalized europium(III) complex

International Nuclear Information System (INIS)

Liu, Yu; Wang, Yafei; Li, Chun; Huang, Ying; Dang, Dongfeng; Zhu, Meixiang; Zhu, Weiguo; Cao, Yong

2014-01-01

A novel tris(dibenzoylmethanato)[5-(2-(4-tert-butylbenzenyl)-5-benzenyl-1,3, 4-oxadiazole-4′)-1,10-phenanthroline]europium(III) [Eu(DBM) 3 (BuOXD-Phen)] containing an electron-transporting oxadiazole-functionalized phenanthroline ligand was synthesized and characterized. Its UV–vis absorption and photoluminescence (PL), as well as the electroluminescence (EL) in polymer light-emitting devices (PLEDs) were investigated. The double-layer PLEDs with a configuration of ITO/PEDOT:PSS (50 nm)/PVK (40 nm)/PFO:PBD (30%):Eu(DBM) 3 (BuOXD-Phen) (1–8 wt %) (80 nm)/Ba (4 nm)/Al (150 nm) were fabricated. Saturated red Eu 3+ ion emission, based on the 5 D 0 → 7 F 2 transition, is centered at a wavelength of 614 nm with a full width at half maximum (FWHM) of 10 nm. The highest external quantum efficiency (QE ext ) of 1.26% at current density of 1.65 mA cm −2 , with a maximum brightness of 568 cd m −2 at 137.8 mA cm −2 was achieved from the device at 1 wt % dopant concentration. - Highlights: • An oxadiazole-functionalized europium(III) complex of Eu(DBM) 3 (BuOXD-Phen) was presented. • The optophysical properties of Eu(DBM) 3 (BuOXD-Phen) were investigated. • Saturated red emission was observed in the PLEDs. • An external quantum efficiency of 1.26% was obtained in these devices

Chloride, bromide and iodide scintillators with europium doping

Science.gov (United States)

Zhuravleva, Mariya; Yang, Kan

2014-08-26

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

The sources and fate of radionuclides emitted to the atmosphere

International Nuclear Information System (INIS)

Sandalls, J.

2001-01-01

The thesis represents an account of the sources and fate of radionuclides entering the atmosphere, and indicates where the candidate, through his own work, has contributed to the overall picture. The sources of the natural and man-made radionuclides found in the atmosphere are identified. New data on emissions from UK coal-fired power stations and UK steel works are reported. Radionuclides produced in nuclear fission and released to the atmosphere in the detonation of nuclear weapons, in nuclear accidents, and through routine discharges from nuclear sites have added to the atmospheric burden of radioactive materials; both acute and chronic low-level emissions are discussed. The various natural processes which remove radionuclides from the atmosphere are described. Soon after release, many radioactive materials become attached to the atmospheric aerosol, but others undergo gas-phase reactions. Some gases are sufficiently long-lived in the troposphere as to find their way into the stratosphere where their fate may be determined by the short-wave radiation from the sun. The nature of the particles of fuel emitted to the atmosphere in the explosion and fire at the Chernobyl nuclear power plant in 1986 are discussed, together with the associated environmental problems. The ground is the major sink for radionuclides leaving the atmosphere, and the behaviour of the more radiologically important radionuclides following deposition is described with special reference to: (i) fallout in both the urban and living environments; (ii) the pathways which may lead to contamination of the food chain; (iii) how the fuel particle fallout from Chernobyl was unique in nuclear accidents; (iv) soil-to-plant transfer of radioelements and (v) how radiation exposure of man can be mitigated in both the contaminated urban and rural environments. (author)

Airborne radionuclides in the proglacial environment as indicators of sources and transfers of soil material.

Science.gov (United States)

Łokas, Edyta; Wachniew, Przemysław; Jodłowski, Paweł; Gąsiorek, Michał

2017-11-01

A survey of artificial ( 137 Cs, 238 Pu, 239+240 Pu, 241 Am) and natural ( 226 Ra, 232 Th, 40 K, 210 Pb) radioactive isotopes in proglacial soils of an Arctic glacier have revealed high spatial variability of activity concentrations and inventories of the airborne radionuclides. Soil column 137 Cs inventories range from below the detection limit to nearly 120 kBq m -2 , this value significantly exceeding direct atmospheric deposition. This variability may result from the mixing of materials characterised by different contents of airborne radionuclides. The highest activity concentrations observed in the proglacial soils may result from the deposition of cryoconites, which have been shown to accumulate airborne radionuclides on the surface of glaciers. The role of cryoconites in radionuclide accumulation is supported by the concordant enrichment of the naturally occurring airborne 210 Pb in proglacial soil cores showing elevated levels of artificial radionuclides. The lithogenic radionuclides show less variability than the airborne radionuclides because their activity concentrations are controlled only by the mixing of material derived from the weathering of different parent rocks. Soil properties vary little within and between the profiles and there is no unequivocal relationship between them and the radionuclide contents. The inventories reflect the pathways and time variable inputs of soil material to particular sites of the proglacial zone. Lack of the airborne radionuclides reflects no deposition of material exposed to the atmosphere after the 1950s or its removal by erosion. Inventories above the direct atmospheric deposition indicate secondary deposition of radionuclide-bearing material. Very high inventories indicate sites where transport pathways of cryoconite material terminated. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ferromagnetic semiconductor-metal transition in heterostructures of europium monoxide

Energy Technology Data Exchange (ETDEWEB)

Stollenwerk, Tobias; Kroha, Johann [Physikalisches Institut der Universitaet Bonn (Germany)

2012-07-01

Experiments on thin films of electron doped europium monoxide show a simultaneous ferromagnetic semiconductor-metal transition which goes along with a huge drop in resistivity over several orders of magnitude. Therefore, this material is a very promising candidate for spintronics applications. We have developed a theory which correctly predicts the simultaneous phase transition in thin films of electron doped EuO and the increase of the Curie temperature T{sub C} with doping concentration. The origin of the increased T{sub C} lies in the enhanced RKKY interaction between the localized 4f moments of the Eu atoms. Therefore, the phase transition is controlled by the population of the conduction band. We investigate the influence of film thickness and interface effects on the population of the conduction band and on the magnetic and electronic properties of the EuO film.

Separation of protactinum, actinium, and other radionuclides from proton irradiated thorium target

Science.gov (United States)

Fassbender, Michael E.; Radchenko, Valery

2018-04-24

Protactinium, actinium, radium, radiolanthanides and other radionuclide fission products were separated and recovered from a proton-irradiated thorium target. The target was dissolved in concentrated HCl, which formed anionic complexes of protactinium but not with thorium, actinium, radium, or radiolanthanides. Protactinium was separated from soluble thorium by loading a concentrated HCl solution of the target onto a column of strongly basic anion exchanger resin and eluting with concentrated HCl. Actinium, radium and radiolanthanides elute with thorium. The protactinium that is retained on the column, along with other radionuclides, is eluted may subsequently treated to remove radionuclide impurities to afford a fraction of substantially pure protactinium. The eluate with the soluble thorium, actinium, radium and radiolanthanides may be subjected to treatment with citric acid to form anionic thorium, loaded onto a cationic exchanger resin, and eluted. Actinium, radium and radiolanthanides that are retained can be subjected to extraction chromatography to separate the actinium from the radium and from the radio lanthanides.

Influence of biofilms on migration of uranium, americium and europium in the environment

International Nuclear Information System (INIS)

Baumann, Nils; Zirnstein, Isabel; Arnold, Thuro

2015-01-01

The report on the influence of biofilms on migration of uranium, americium and europium in the environment deals with the contamination problems of uranium mines such as SDAG WISMUT in Saxonia and Thuringia. In mine waters microorganisms form a complex microbiological biocoenosis in spite of low pH values and high heavy metal concentrations including high uranium concentrations. The analyses used microbiological methods like confocal laser scanning microscopy and molecular-biological techniques. The interactions of microorganism with fluorescent radioactive heavy metal ions were performed with TRLFS (time resolved laser-induced fluorescence spectroscopy).

Public Health Goal for Naturally Occurring Radionuclides in Groundwater

International Nuclear Information System (INIS)

Kamel, N.H.M.; Omar, H.A.; El-Baset, L.A.

2008-01-01

Naturally occurring and man-made radionuclide in groundwater may have a health hazardous to some residents. The objective of this work is to provide criteria for safety of drinking-water with respect to the chemical parameters and the radionuclide content. The annual effective dose for the consumption of drinking water was considered. Ground water samples were selected from different sites in Egypt, that have the most population, it were taken from aquifer regions along Giza sites in Egypt. Chemical analyses for the major anions, cations, and the radiological analyses were tested . Activity concentrations (Bq/l) of the gross alpha and the gross beta activities of our investigated samples were compared with the maximum contaminant level (MCL) of the world health organization (WHO). Some of the water samples were found to have a higher of gross beta and alpha particles than the MCL. Alpha activity were found depending on to the total dissolved solids (TDS) content of the water samples. Gamma activity concentrations were analyzed using low background germanium detector, the higher of activity values was found in some investigated samples is due to increasing of 226 Ra and 228 Ra activities. Tritium activity concentrations also were measured using soft beta liquid scintillation counter, it was found lower than the MCL. Our investigated samples were found to have a higher concentrations of the phosphate, nitrites, iron, and manganese contents than the maximum permissible limit, all the ground water samples were found to have a higher of silica and alumina content. Commercial carbon powder and natural clay materials were tested as ion exchangers for the removal of inorganic contaminants in the ground water samples. Clay materials was found to have a higher selectivity than activated carbon for the removal of radionuclides, phosphates, nitrites, and manganese content at the ground water samples

Novel europium (III)-gatifloxacin complex structure with dual functionality for pH sensing and metal recognition in aqueous environment

Science.gov (United States)

Chen, Muhua; Zheng, Yuhui; Gao, Jinwei; Wang, Qianming

2016-10-01

A new type of Eu(III)-gatifloxacin complex with characteristic red luminescence has been prepared. Due to the presence of ionization effect linked to the organic chromophore, the molecular fluorescent sensor demonstrated variable pH-sensitive absorption and emission curves. The red emission derived from europium ions was strong during pH range 8-10. Between pH = 7 and 4, the europium emission remained relatively stable and fluorescence signals of gatifloxacin has been improved substantially. Under acidic conditions (pH = 1 to 3), the dramatic changes in the emission colors (from red, yellow to green) were clearly observed. Moreover, the excitation wavelength can be extended into the visible light range (Ex = 411 nm) by using the concentration effect experiment. Importantly, it gave turn-off emissions in the presence of Cu2+ or Fe3+ and the detection limits were determined to be 6.5 μM for Cu2+ and 6.2 μM for Fe3+ respectively.

Distribution coefficients (Kd's) for use in risk assessment models of the Kara Sea.

Science.gov (United States)

Carroll, J; Boisson, F; Teyssie, J L; King, S E; Krosshavn, M; Carroll, M L; Fowler, S W; Povinec, P P; Baxter, M S

1999-07-01

As a prerequisite for most evaluations of radionuclide transport pathways in marine systems, it is necessary to obtain basic information on the sorption potential of contaminants onto particulate matter. Kd values for use in modeling radionuclide dispersion in the Kara Sea have been determined as part of several international programs addressing the problem of radioactive debris residing in Arctic Seas. Field and laboratory Kd experiments were conducted for the following radionuclides associated with nuclear waste: americium, europium, plutonium, cobalt, cesium and strontium. Emphasis has been placed on two regions in the Kara Sea: (i) the Novaya Zemlya Trough (NZT) and (ii) the mixing zones of the Ob and Yenisey Rivers (RMZ). Short-term batch Kd experiments were performed at-sea on ambient water column samples and on samples prepared both at-sea and in the laboratory by mixing filtered bottom water with small amounts of surficial bottom sediments (particle concentrations in samples = 1-30 mg/l). Within both regions, Kd values for individual radionuclides vary over two to three orders of magnitude. The relative particle affinities for radionuclides in the two regions are americium approximately equal to europium > plutonium > cobalt > cesium > strontium. The values determined in this study agree with minimum values given in the IAEA Technical Report [IAEA, 1985. Sediment Kd's and Concentration Factors for Radionuclides in the Marine Environment. Technical Report No. 247. International Atomic Energy Agency, Vienna.]. Given the importance of Kd's in assessments of critical transport pathways for radionuclide contaminants, we recommend that Kd ranges of values for specific elements rather than single mean values be incorporated into model simulations of radionuclide dispersion.

Behavior of radionuclides in sanitary landfills.

Science.gov (United States)

Chang, K C; Chian, E S; Pohland, F G; Cross, W H; Roland, L; Kahn, B

1984-01-01

his study was undertaken to evaluate the possibility of disposing low-level radioactive waste in sanitary landfills with leachate containment to prevent environmental releases. To meet this objective, two simulated landfills, each 200 l. in volume and containing 55 kg of municipal refuse, were operated in the laboratory with simulated rainfall additions for a 9-month period to observe the extent to which radio-cobalt, -cesium, -strontium and tritium were leached into the liquid phase. One of the units was operated with leachate recycle, the other as a single pass control. Liquid samples were analyzed weekly for 3H, 58Co, 85Sr and 134Cs tracers. Weekly analyses were also performed for approximately 30 parameters to define the degree of stabilization of the waste. Major parameters included BOD, COD, pH and concentrations of specific organics, metals and gases. Concentrations of stable cobalt, strontium and cesium were also measured periodically. Soluble radioactivity levels in both systems were reduced by factors of 50 for 58Co, 5 for 85Sr and 7 for 134Cs, taking radioactive decay and dilution into account. Some radionuclide removal from the liquid phase was associated with major chemical changes in the landfills that occurred within 80 days for the control system and within 130 days for the recycle unit. Observed acid, sulfide, and CO2 concentrations suggested mechanisms for removing some of the radionuclides from leachate. Detection of 3H in the off-gas indicated that less than 1% of tritiated waste became airborne. The waste in the leachate recycle unit was more completely stabilized than in the control unit.

The enrichment behavior of natural radionuclides in pulverized oil shale-fired power plants

International Nuclear Information System (INIS)

Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

2014-01-01

The oil shale industry is the largest producer of NORM (Naturally Occurring Radioactive Material) waste in Estonia. Approximately 11–12 million tons of oil shale containing various amounts of natural radionuclides is burned annually in the Narva oil shale-fired power plants, which accounts for approximately 90% of Estonian electricity production. The radionuclide behavior characteristics change during the fuel combustion process, which redistributes the radionuclides between different ash fractions. Out of 24 operational boilers in the power plants, four use circulating fluidized bed (CFB) technology and twenty use pulverized fuel (PF) technology. Over the past decade, the PF boilers have been renovated, with the main objective to increase the efficiency of the filter systems. Between 2009 and 2012, electrostatic precipitators (ESP) in four PF energy blocks were replaced with novel integrated desulphurization technology (NID) for the efficient removal of fly ash and SO 2 from flue gases. Using gamma spectrometry, activity concentrations and enrichment factors for the 238 U ( 238 U, 226 Ra, 210 Pb) and 232 Th ( 232 Th, 228 Ra) family radionuclides as well as 40 K were measured and analyzed in different PF boiler ash fractions. The radionuclide activity concentrations in the ash samples increased from the furnace toward the back end of the flue gas duct. The highest values in different PF boiler ash fractions were in the last field of the ESP and in the NID ash, where radionuclide enrichment factors were up to 4.2 and 3.3, respectively. The acquired and analyzed data on radionuclide activity concentrations in different PF boiler ashes (operating with an ESP and a NID system) compared to CFB boiler ashes provides an indication that changes in the fuel (oil shale) composition and boiler working parameters, as well as technological enhancements in Estonian oil shale fired power plants, have had a combined effect on the distribution patterns of natural radionuclides in

Radionuclide generators

International Nuclear Information System (INIS)

Lambrecht, R.M.; Wollongong Univ.; Tomiyoshi, K.; Sekine, T.

1997-01-01

The present status and future directions of research and development on radionuclide generator technology are reported. The recent interest to develop double-neutron capture reactions for production of in vivo generators; neutron rich nuclides for radio-immunotherapeutic pharmaceuticals: and advances with ultra-short lived generators is highlighted. Emphasis is focused on: production of the parent radionuclide; the selection and the evaluation of support materials and eluents with respect to the resultant radiochemical yield of the daughter, and the breakthrough of the radionuclide parent: and, the uses of radionuclide generators in radiopharmaceutical chemistry, biomedical and industrial applications. The 62 Zn → 62 Cu, 66 Ni → 66 Cu, 103m Rh → 103 Rh, 188 W → 188 Re and the 225 Ac → 221 Fr → 213 Bi generators are predicted to be emphasized for future development. Coverage of the 99 Mo → 99m Tc generator was excluded, as it the subject of another review. The literature search ended June, 1996. (orig.)

Disturbance of deposition and removal of plutonium

International Nuclear Information System (INIS)

Fukuda, Satoshi

1992-01-01

The chelation therapy using DTPA (diethylenetriaminepentaacetic acid) and a new drug, CBMIDA [catechol 3, 6-bis (methyleiminodiacetic acid)] showing more effectiveness on removal of plutonium and lower toxicity than DTPA, is available for occupational exposure but is difficult for public exposure, because there are many reluctant problems on their toxicities, administration routes and times, physical conditions of victims etc. We demonstrated that active amino acid calcium (AAACa), a natural product which mixed oyster shell electrolysate and amino acids of seaweeds, could remove plutonium from bone and liver in rats. The removing methods of radionuclides using the bioavailability of AAACa will be utilized for public exposures and resolve the reluctant problems accompanied with a chelation therapy for occupational exposure. (author)

Chemical controls on subsurface radionuclide transport

International Nuclear Information System (INIS)

King, K.J.; Killey, R.W.D.

1990-01-01

Chemical and biochemical processes can affect the movement of contaminants in groundwater. Materials can be almost completely removed from circulation by processes such as precipitation and coprecipitation. Organic compounds or contaminants that are hazardous may be degraded or formed during groundwater transport. Studies at the Chalk River Laboratories of AECL have focused on radionuclide transport, although other contaminants have been and are being investigated. This paper summarizes findings from research that extends back more than 30 years. Much of the work on reactive contaminant transport has centered on 90 Sr; other contaminants have also been considered, however, and features of their behaviour are also reviewed. (25 refs., 5 figs., 4 tabs.)

Simultaneous treatment of chlorinated organics and removal of metals and radionuclides with bimetals and complexing acids - application to surfactant solutions

Energy Technology Data Exchange (ETDEWEB)

Korte, N.E.; Gu, B. [Oak Ridge National Lab., TN (United States)

1997-10-01

Currently available methods for separation and treatment of radioactive mixed waste are typically energy-intensive, and often require high temperatures. Passive methods that operate at ambient temperatures are needed. The purpose of this task is to develop bimetallic substrates, using a base metal such as iron and a promoter metal such as palladium (Pd), to provide a passive, low-energy solution to a substantial portion of DOE`s mixed-waste problem. This technology consists of a porous medium that can simultaneously dechlorinate hazardous organics such as TCE and polychlorinated biphenyls (PCBs) at the same time that it removes metallic and hazardous wastes from a solvent/surfactant solution. The porous medium consists of a bimetallic substrate such as palladized iron (Pd/Fe). Palladium is readily chemically plated on iron and preliminary studies suggest that only 0.05 to 0.1% Pd is needed for an efficient reaction. Thus, the cost of the material is reasonable especially is it is long-lived or can be regenerated. Field implementation would consist of the passage of a surfactant-laden, mixed waste through a column or bed of the bimetallic substrate. The organic component of this mixed waste may contain semivolatile compounds such as PCBs or pesticides and herbicides. The bimetal simultaneously removes radionuclides and metals and degrades halogenated hydrocarbons. Virtually any concentration can be treated. Following reaction of the bimetal with the waste stream, the resulting effluent will consist of an uncontaminated aqueous solution of surfactant or solvent that can be reused. The bimetal would then be rinsed with a dilute mineral acid or a mild complexing acid (e.g., oxalic or citric acid) to regenerate the surface and to remove sorbed metals and non-hazardous organic residue. The latter effluent would be low-level radioactive waste in some cases, but it would now be much easier to manage and be of a lower volume than the original mixed waste.

Environmentally important radionuclides in non-proliferative fuel cycles

International Nuclear Information System (INIS)

Kaye, S.V.; Till, J.E.

1978-01-01

Increased emphasis in energy research is being given to the development of nonproliferative nuclear fuel cycles and to the assessment of potential release of radionuclides to the environment from these new cycles. Four radionuclides, 14 C, 3 H, 99 Tc, and 232 U, due to lack of adequate knowledge or anticipated increased production in nonproliferative fuel cycles, may require renewed consideration. Our projections indicate that releases of 14 C by the global nuclear industry could exceed the natural production rate of 3.8 x 10 4 Ci/y by the year 2000 and could eventually stabilize at 2.3 times that rate. Tritium may become increasingly important, because recent data from fast reactors (of the nonproliferative type) have confirmed production rates up to 13 times greater than previous estimates. Present radwaste systems do not remove tritium. Recent experiments on the uptake of 99 Tc reveal that soil-to-plant concentration factors for technetium appear to be two to three orders of magnitude greater than the value of 0.25 which has been adopted routinely in radiological assessments. Research is needed to determine reliable 99 Tc soil-to-plant concentration factors because this radionuclide could be released at reprocessing and enrichment facilities. New calculations for certain reactors indicate that 232 U may be formed in concentrations up to 4000 ppm. If accurate, such data will require careful analysis of possible releases of 232 U because of external and food chain exposures. The environmental health aspects of these four radionuclides are discussed, as well as the potential for their release to the environment from nonproliferative fuel cycles. (author)

Radionuclides in terrestrial ecosystems

International Nuclear Information System (INIS)

Allen, S.E.; Horrill, A.D.; Howard, B.J.; Lowe, V.P.W.; Parkinson, J.A.

1983-07-01

The subject is discussed under the headings: concentration and spatial distribution of radionuclides in grazed and ungrazed saltmarshes; incorporation of radionuclides by sheep grazing on an estuarine saltmarsh; inland transfer of radionuclides by birds feeding in the estuaries and saltmarshes at Ravenglass; radionuclides in contrasting types of coastal pastures and taken up by individual plant species found in west Cumbria; procedures developed and used for the measurement of alpha and gamma emitters in environmental materials. (U.K.)

Radionuclide data

International Nuclear Information System (INIS)

Anon.

1992-01-01

Chapter 8 presents tables on selected alpha, beta, gamma and x-ray emitters by increasing energy; information on specific activity for selected radionuclides; naturally occurring radionuclides; the natural decay series; and the artificially produced neptunium series. A table of alpha emitters is listed by increasing atomic number and by energy. The table of β emitters presented is useful in identifying β emitters whose energies and possibly half-lives have been determined by standard laboratory techniques. It is also a handy guide to β-emitting isotopes for applications requiring specific half-lives and/or energies. Gamma rays for radionuclides of importance to radiological assessments and radiation protection are listed by increasing energy. The energies and branching ratios are important for radionuclide determinations with gamma spectrometry detectors. This section also presents a table of x-ray energies which are useful for radiochemical analyses. A number of nuclides emit x-rays as part of their decay scheme. These x-rays may be counted with Ar proportional counters, Ge planar or n-type Ge co-axial detectors, or thin crystal NaI(T1) scintillation counters. In both cases, spectral measurements can be made and both qualitative and quantitative information obtained on the sample. Nuclear decay data (energy and probability by radiation type) for more than one hundred radionuclides that are important to health physicists are presented in a schematic manner

Luminescent sensing of organophosphates using europium(III) containing imprinted polymers prepared by RAFT polymerization

International Nuclear Information System (INIS)

Southard, Glen E.; Van Houten, Kelly A.; Ott, Edward W.; Murray, George M.

2007-01-01

Molecularly imprinted polymers capable of sensing organophosphorous compounds by luminescence have been prepared by reversible addition fragmentation chain transfer (RAFT) polymerization. The polymer contained a dithiobenzoate substituted tris(β-diketonate) europium(III) complex which served as a polymerization substrate and as a luminescent binding site for pinacolyl methylphosphonate (PMP), the hydrolysis product of the nerve agent Soman. The resultant polymer allowed quantitation of PMP in the low ppb range with minimal interference from similar compounds. Polymers were characterized by luminescence spectroscopy and scanning electron microscopy

Heavy metals and their radionuclides uptake by Bacillus Licheniformis

International Nuclear Information System (INIS)

Ramadan, A.A.; Ahmed, M.M.; Abo-state, M.A.M.; Sarhan, M.; Faroqe, M.

2007-01-01

Bacillus licheniformis is a gram positive spore forming bacterium. Different concentrations of cobalt affected the ability of Co uptake and growth of Bacillus licheniformis. As the concentration increased, both the uptake and growth were decreased. Maximum Co uptake was found at ph 7.0, while for growth was ph 8.0. The optimum temperature for uptake and growth was 40 degree C and 20% inoculum size represents the maximum cobalt uptake by Bacillus licheniformis. Also, maximum uptake was recorded after 72 hours, incubation period. As the concentration of cesium was increased till 400 mg/l, the uptake was also increased. The optimum cesium uptake and growth was at ph 8.0. The optimum growth was at 45 degree C while Cs uptake was found at 35 degree C and 15% inoculum size represented the maximum Cs uptake. After 72 hour incubation period, maximum Cs uptake was recorded. Generally, Bacillus licheniformis removed more than 80% of Co and 50% of Cs from the broth medium. Addition of clay to Bacillus licheniformis increased both Co or Cs uptake. Bacillus licheniformis was gamma resistant and 10 KGy reduced the viability by 5.3 log cycles. The irradiated and non-irradiated cultures can grow on 500 or 700 mg Co or Cs. Bacillus licheniformis removed 99.32% of the Co radionuclides and 99.28% of Cs radionuclides

Factors influencing the transfer of radionuclides in agricultural food chains

International Nuclear Information System (INIS)

Vandecasteele, C.M.; Zeevaert, Th.; Kirchmann, R.

1991-01-01

The applications of nuclear energy have led and will continue to lead to routine or accidental discharges of radioactive elements into the atmospheric and/or aquatic environment resulting in the exposure of populations to ionising radiations. The radionuclides released into the atmosphere are transported downwind, dispersed by the atmospheric mixing phenomena and progressively settled by deposition processes. During the passage of the radioactive cloud, people are irradiated externally as well as internally by inhalation. After the passage of the cloud, exposure of the population continues via three main pathways: external irradiation from the radionuclides deposited on the ground, inhalation of resuspended contaminated particles and ingestion of contaminated food products. When discharged into aquatic systems, the radionuclides can be partly removed from the aqueous phase by adsorption on suspended solids and bottom sediments. As the radioactivity disperses, there is a continuing exchange between water and solid phases. The contaminated sediments deposited on the banks of rivers, lakes and coastal area lead to external irradiation of people spending time at these sites. The residual activity in water exposes man internally through the ingestion of drinking water and food products, contaminated by irrigation of vegetation and ingestion of water by livestock. Among the various exposure pathways, the main route of entry of fission products and most other artificial radionuclides into man has been identified as uptake from the diet. Since agricultural products constitute the basic diet of most populations, the fate and behavior of radionuclides in agricultural ecosystems are of primary importance when assessing the exposure risk of man from environmental releases of radioactivity. 69 refs., 4 figs

A novel photoluminescent and photochromic europium complex

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

A ternary europium complex of 4-aminobutyric acid (ABA) with 1,10-phenanthroline (phen) [Eu2(ABA)4 (phen)4](phen)4(ClO4)6 was synthesized and characterized by X-ray single crystal diffraction. The result shows that 4-aminobutyric acid exists in zwitterion form in the binuclear complex and that the carboxylates coordinate with Eu3+ ion in bidentate bridging and tridentate chelating-bridging modes. There are two types of phen molecules, one is coordinated and the other is uncoordinated. When excited by YAG: Nd laser with 355 nm light, the title complex can emit strong red fluorescence, and its high-resolution emission spectrum was recorded at 77 K. The Eu3+ ion site is in low symmetry, which is in agreement with the result of X-ray single crystal diffraction analysis. When irradiated with a mercury lamp, the aqueous solution of the title complex can perform photochromism with the color change from colorless to green and the green color can fade away in the dark. The photochromic response time is related to the concentration and pH of the solution, the temperature and the light intensity.

Removal of mercury from water using pottery

International Nuclear Information System (INIS)

Helal, A.A.A.

2006-01-01

In a previous study, the sorption of radiocobalt by powdered pottery materials was investigated. The use of these materials as immobilization matrix for liquid radioactive waste requires the employment of pottery vessels. Therefore, the present study aims to give detailed investigations of the decontamination of radionuclides and toxic elements using pottery containers. These investigations are equally useful to elucidate how far these vessels can be utilized for water purification through decontamination of toxic and heavy metals. The radionuclide or heavy metal removal capability using pottery pots, as low cost sorbents, has been investigated for both radioactive ( 203 Hg) and stable mercury. The results indicated that Hg 2+ is better removed by pottery from neutral to alkaline solutions. The capacity of the used pottery container (100 ml in volume) for complete removal of mercury was found to reach 3 x 10 -4 mol/l, and the time needed was 8 hours. The sorption process was suggested to occur via adsorption and ion exchange. The effect of presence of humic or fulvic acid, as ligands abundant in water, is also investigated. The results imply that, in absence of humic or fulvic acid the sorption follows the expected behaviour, i.e. sorption sites with similar affinity for mercury. In presence of humic or fulvic acid, additional sorption sites are available by the organic molecule when it is associated to the pottery. (orig.)

Radionuclide separations and processing for defense water management

International Nuclear Information System (INIS)

Fryberger, T.B.

1993-01-01

An overview is given of the Department of Energy's Efficient Separations and Processing Integrated Program (ESPIP). This program sponsors research in advanced chemical separations for removal of radionuclides and hazardous components from radioactive defense wastes. Separations processing will reduce the volume of high-level waste that must be disposed of in a deep geological repository and will improve the quality of low-level wastes acceptable for near-surface disposal. DOE defense complex processing needs as well as technologies that are currently under development in the program are discussed

Radionuclide generators

International Nuclear Information System (INIS)

Lambrecht, R.M.

1983-01-01

The status of radionuclide generators for chemical research and applications related to the life sciences and biomedical research are reviewed. Emphasis is placed upon convenient, efficient and rapid separation of short-lived daughter radionuclides in a chemical form suitable for use without further chemical manipulation. The focus is on the production of the parent, the radiochemistry associated with processing the parent and daughter, the selection and the characteristic separation methods, and yields. Quality control considerations are briefly noted. The scope of this review includes selected references to applications of radionuclide generators in radiopharmaceutical chemistry, and the life sciences, particularly in diagnostic and therapeutic medicine. The 99 Mo-sup(99m)Tc generator was excluded. 202 references are cited. (orig.)

Measurements of europium-152 depth profile of stone embankments exposed the Nagasaki atomic bomb for neutron spectrum analysis

International Nuclear Information System (INIS)

Tatsumi-Miyajima, Junko; Shimasaki, Tatsuya; Okajima, Shunzo; Takada, Jitsuya; Yoshida, Masahiro; Takao, Hideaki; Okumura, Yutaka; Nakazawa, Masaharu.

1990-01-01

Quantitative measurement of neutron-induced radionuclide of 152 Eu in rocks near the hypocenter (ground center of the atomic bomb explosion) in Nagasaki was performed to obtain the depth profiles and calculate the neutron energy spectrum. Core samples were drilled and taken from the stone embankments on both sides of river within a radius of 500 m from the hypocenter. After cutting each core into about 27 mm-thick sections, each section was measured its gamma-ray spectrum with a pure germanium semiconductor detector and analyzed a content of natural europium by the activation method. The highest value 8.0 x 10 -2 Bq/μg of 152 Eu at the time of the blast was obtained from the surface plates of rock cores collected near the hypocenter. The surface activity of cores was reduced with increasing the slant distances from the hypocenter. The slopes of the depth profiles were similar among samples taken from the same location. In order to analyze the depth profile of 152 Eu activity in rock andesite, experiments using a fast neutron reactor and thermal neutron reactor were carried out. Comparing the measurements on the A-bomb exposure rock with the simulated results at the reactors, among the experiments, the depth profile using the neutron moderator of 10 mm polyethylene was closed to that obtained from the A-bomb exposed samples. The experiment of thermal neutron incidence only could not reproduce the profiles from the A-bomb exposed samples. This fact indicates that the depth profiles of 152 Eu in rock exposed to the A-bomb include valuable information concerning the neutron spectrum and intensity. (author)

Study of Polymeric Luminescent Blend (PC/PMMA) Doped with Europium Complex under Gamma-Iradiation

International Nuclear Information System (INIS)

Parra, D. F.

2006-01-01

Spectroscopic properties of blends formed by bisphenol-A polycarbonate (PC) and poly(methyl methacrylate) (PMMA) doped with europium in organic complex were studied. Polymeric luminescent blends are potential materials for many applications; however, little information has been reported concerning the stability under thermal and radiation conditions. Luminescent films were synthesized from europium thenoyltrifluoroacetonate at different concentrations doped in PC/PMMA blends. Films produced of the luminescent polymer blend were irradiated in a 60 C o source. Their luminescent properties, in the solid state, as well as, the thermal oxidative resistance after gamma irradiation was investigated. These systems were characterized by elemental analysis, thermogravimetry (TGA), differential scanning calorimetry (DSC) and infrared spectroscopy (FTIR). Based on TGA data, the thermal stability of PC/PMMA:(tta)3 system is higher than the polymer blend. The DSC results indicated that those new systems are chemically stables. The emission spectra of the Eu 3 +-tta complex doped in the PC/PMMA recorded at 298 and 77 K exhibited the characteristic bands arising from the 5 D 0 →7 F J transitions (J = 0-6). The luminescence intensity decreases with increasing of precursor concentration in the doped polymer obtained by chemical reaction. This result is different from that of samples obtained by physical method in melting doping. The blend was irradiated under ionizing radiation of 60 C o source. After irradiation of the luminescent films the physical properties of luminescence, thermal and oxidative stability were evaluated.(Fapesp and Cnpq financial support)

The condition for electroplex emission from an europium complex doped poly( N-vinylcarbazole)

Science.gov (United States)

Zhang, T.; Xu, Z.; Qian, L.; Tao, D. L.; Teng, F.; Gao, X.; Xu, X. R.

2005-10-01

Spectral characteristics of photoluminescence (PL) and electroluminescence (EL) of poly( N-vinylcarbazole) (PVK) matrices doped with a novel europium complex Eu(aspirin) 3phen were investigated. A red-shift and broadening were observed in the EL spectra but not in the PL ones. However, neither red-shift nor broadening were observed in the EL spectra of PVK doped with a similar complex with the same ligand, terbium complex (Tb(aspirin) 3phen). This result suggests the formation of electroplexes in blend systems, which is likely due to inefficient energy transfer from host molecules to dopant molecules.

Inherently safe aircooling for the storage of self-heating configurations of radionuclides

International Nuclear Information System (INIS)

Hame, W.; Klein, D.; Pirk, H.

1980-01-01

NUKEM developed a technical concept of a radionuclide storage facility based on aircooling, which provides that - the radionuclides, i.e. spent fuel elements, are tightly canned in steel canisters - the canned elements are put into individual cooling channels, which form the storage rack within the storage cell - the produced heat is removed from the surface of the canisters through free convection. This cooling concept shows the following advantages: - The cooling is inherently safe, as the driving force of the coolant is reliably supplied by the heat production of the system to be cooled. - The system is self-controlled and self-regulated because of the physically based correlation of heat production, heat transfer coefficients and air flow resistances. (orig.) 891 RB/orig. 892 MKO [de

environmental studies for removal of some radioactive elements using zirconium silicate as inorganic ion exchange material

International Nuclear Information System (INIS)

El-Aryan, Y.F.A.

2007-01-01

inorganic ion exchangers have a good potential than the commonly used organic ones for removal and separation of radionuclides from irradiated nuclear fuel solutions. therefore, the main aim of this work is directed to find the optimum conditions for removal of some radionuclides such as Cs + ,Co 2+ ,and Eu 3+ by the prepared zirconium silicate as cation exchanger. the following items will be involved:-1- preparation of zirconium silicate as a cation exchanger. 2- characterization of the prepared exchanger using IR spectra, X-ray diffraction patterns, DTA and TG analyses. 3-chemical stability, capacity and equilibrium measurements will be determined on the materials using at different conditions (heating temperature and reaction temperature). 4- ion exchange isotherms. 5- breakthrough curves for removal of the investigated metal ions on the prepared exchanger under certain conditions

The different-ligand complexing of europium with complexones and β-diketones in micellar solution

International Nuclear Information System (INIS)

Svetlova, I.E.; Dobrynina, N.A.; Smirnova, N.S.; Martynenko, L.I.; Evseev, A.M.; Savitskij, A.P.

1989-01-01

Method of pH-metric titration with mathematical simulation was used to study the effect of nonionic surfactant (polyoxyethyleneoctylphenyl este) on stability of europium complexes with cyclohexanediaminetetraacetic and ethylenediaminetetraacetic acids. Optimal conditions for ternary complex formation in the system Eu 3+ -complexone-β-diketone at pH 7.0-9.0 were found. Complex-compositions were determined and their stability constants were calculated. It is shown that complex stability decreases by several orders in micellar solutions, tecause β-diketone introduction to the solution decreases thermodynamic stability of complexes

Radionuclides in radiation-induced bystander effect; may it share in radionuclide therapy?

Science.gov (United States)

Widel, M

2017-01-01

For many years in radiobiology and radiotherapy predominated the conviction that cellular DNA is the main target for ionizing radiation, however, the view has changed in the past 20 years. Nowadays, it is assumed that not only directed (targeted) radiation effect, but also an indirect (non-targeted) effect may contribute to the result of radiation treatment. Non-targeted effect is relatively well recognized after external beam irradiation in vitro and in vivo, and comprises such phenomena like radiation-induced bystander effect (RIBE), genomic instability, adaptive response and abscopal (out of field) effect. These stress-induced and molecular signaling mediated phenomena appear in non-targeted cells as variety responses resembling that observed in directly hit cells. Bystander effects can be both detrimental and beneficial in dependence on dose, dose-rate, cell type, genetic status and experimental condition. Less is known about radionuclide-induced non-targeted effects in radionuclide therapy, although, based on characteristics of the radionuclide radiation, on experiments in vitro utilizing classical and 3-D cell cultures, and preclinical study on animals it seems obvious that exposure to radionuclide is accompanied by various bystander effects, mostly damaging, less often protective. This review summarizes existing data on radionuclide induced bystander effects comprising radionuclides emitting beta- and alpha-particles and Auger electrons used in tumor radiotherapy and diagnostics. So far, separation of the direct effect of radionuclide decay from crossfire and bystander effects in clinical targeted radionuclide therapy is impossible because of the lack of methods to assess whether, and to what extent bystander effect is involved in human organism. Considerations on this topic are also included.

First principles description of the insulator-metal transition in europium monoxide

KAUST Repository

Wang, Hao

2012-02-01

Europium monoxide, EuO, is a ferromagnetic insulator. Its electronic structure under pressure and doping is investigated by means of density functional theory. We employ spin polarized electronic structure calculations including onsite electron-electron interaction for the localized Eu 4f and 5d electrons. Our results show that under pressure the ferromagnetism is stable, both for hydrostatic and uniaxial pressure, while the compound undergoes an insulator-metal transition. The insulator-metal transition in O deficient and Gd doped EuO is reproduced for an impurity concentration of 6.25%. A 10 monolayer thick EuO(1 0 0) thin film is predicted to be an insulator with a narrow band gap of 0.08 eV. © 2011 Elsevier B.V. All rights reserved.

Novel fungus-Fe{sub 3}O{sub 4} bio-nanocomposites as high performance adsorbents for the removal of radionuclides

Energy Technology Data Exchange (ETDEWEB)

Ding, Congcong [Institute of Plasma Physics, Chinese Academy of Science, P.O. Box 1126, Hefei 230031 (China); University of Science and Technology of China, Hefei 230000 (China); Cheng, Wencai [Institute of Plasma Physics, Chinese Academy of Science, P.O. Box 1126, Hefei 230031 (China); Sun, Yubing, E-mail: sunyb@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Science, P.O. Box 1126, Hefei 230031 (China); School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, 215123 Suzhou (China); School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206 (China); Wang, Xiangke, E-mail: xkwang@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Science, P.O. Box 1126, Hefei 230031 (China); School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, 215123 Suzhou (China); School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206 (China); Faculty of Engineering, King Abdulaziz University, Jeddah 21589 (Saudi Arabia)

2015-09-15

Highlights: • Fungus was used as a template for the assembly of nano-Fe{sub 3}O{sub 4}. • Fungal template directed the nano-Fe{sub 3}O{sub 4} structure from the micro-scale level. • Fungal template enhanced the dispersity and stability of nano-Fe{sub 3}O{sub 4}. • Fungus-Fe{sub 3}O{sub 4} exhibited high sorption capacity for Sr(II), Th(IV) and U(VI). • Fungus-Fe{sub 3}O{sub 4} possessed satisfactory regeneration performance and reusability. - Abstract: The bio-nanocomposites of fungus-Fe{sub 3}O{sub 4} were successfully synthesized using a low-cost self-assembly technique. SEM images showed uniform decoration of nano-Fe{sub 3}O{sub 4} particles on fungus surface. The FTIR analysis indicated that nano-Fe{sub 3}O{sub 4} was combined to the fungus surface by chemical bonds. The sorption ability of fungus-Fe{sub 3}O{sub 4} toward Sr(II), Th(IV) and U(VI) was evaluated by batch techniques. Radionuclide sorption on fungus-Fe{sub 3}O{sub 4} was independent of ionic strength, indicating that inner-sphere surface complexion dominated their sorption. XPS analysis indicated that the inner-sphere radionuclide complexes were formed by mainly bonding with oxygen-containing functional groups (i.e., alcohol, acetal and carboxyl) of fungus-Fe{sub 3}O{sub 4}. The maximum sorption capacities of fungus-Fe{sub 3}O{sub 4} calculated from Langmuir isotherm model were 100.9, 223.9 and 280.8 mg/g for Sr(II) and U(VI) at pH 5.0, and Th(IV) at pH 3.0, respectively, at 303 K. Fungus-Fe{sub 3}O{sub 4} also exhibited excellent regeneration performance for the preconcentration of radionuclides. The calculated thermodynamic parameters showed that the sorption of radionuclides on fungus-Fe{sub 3}O{sub 4} was a spontaneous and endothermic process. The findings herein highlight the novel synthesis method of fungus-Fe{sub 3}O{sub 4} and its high sorption ability for radionuclides.

Radionuclide cardiography in medical practice

International Nuclear Information System (INIS)

Strangfeld, D.; Mohnike, W.; Schmidt, J.; Heine, H.; Correns, H.J.

1986-01-01

This publication is a compendium on all aspects of radionuclide diagnostics concerning cardiovascular system diseases. Starting with introductory remarks on the control of cardiovascular diseases the contribution of radionuclide cardiology to functional cardiovascular diagnostics as well as pathophysiological and pathobiochemical aspects of radiocardiography are outlined. Radiopharmaceuticals used in radiocardiography, physical and technical problems in application of radionuclides and their measuring techniques are discussed. In individual chapters radionuclide ventriculography, myocardial scintiscanning, circulatory diagnostics, radionuclide diagnostics of arterial hypertension, of thrombosis and in vitro diagnostics of thrombophilia are treated in the framework of clinical medicine

The speciation of radionuclides in sediments and soils. Part II. Studies with a sequential organic extraction procedure

International Nuclear Information System (INIS)

Voss, H.A.; Williams, G.A.; Cooper, M.B.

1983-07-01

A series of chemical extractions with a range of organic solvents has been performed to investigate the speciation of radionuclides in soil and sediment samples from the Mt. Brockman area in the Northern Territory. The major result is that of all the organic solvents used in the extractions, only acetic acid removes large proportions of the radionuclides 210 Pb (ca. 30-70%) and 226 Ra (10-55%) from the soil and sediment samples. The failure of the other organic solvents, and in particular dimethylformamide, to extract appreciable amounts of these radionuclides is taken to indicate that 210 Pb and 226 Ra are not present as discrete metal complexes of organic ligands. The overriding conclusion, that the acidic nature of the solvent is the most important property in releasing the bound radionuclides into solution, suggests that even under mildly acidic conditions encountered in the environment significant amounts of 210 Pb and 226 Ra may be released for transportation

Development of long-lived radionuclide partitioning technology

Energy Technology Data Exchange (ETDEWEB)

Yoo, Jae Hyung; Lee, Eil Hee; Kim, Kwang Wook; Yang, Han Beom; Chung, Dong Yong; Lim, Jae Kwan; Shin, Young Jun; Kim, Heung Ho; Kown, Sun Gil; Kim, Young Hwan; Hwang, Doo Seung

1996-07-01

This study has been focused on the development of unit processes for partitioning in the 1st stage, and experimentally carried out to examine the separation characteristics and operation conditions on the following unit processes. (1) Removal of a small amount of uranium by extraction with TBP, (2) Removal of Zr and Mo and destruction of nitric acid by uranium by denitration with formic acid, (3) Co-precipitation of Am, Np and RE oxalic acid, (4) Dissolution and destruction of oxalate by hydrogen peroxide, (5) Co-extraction of Am, Np and RE by nitric acid, (8) Back-extraction of Np by oxalic acid, (9) Adsorption and elution of Cs and Sr by zeolite, and (10) Advanced separation of radionuclide by electrochemical REDOX method. The results obtained from each unit process will be use as the basic materials for the establishment of optimal partitioning and design of process equipment. (author). 46 refs., 54 tabs., 222 figs.

Metabolism of radionuclides in domestic animals

International Nuclear Information System (INIS)

Wirth, E.; Leising, C.

1986-01-01

The reactor accident at Chernobyl has shown that shortly after the contamination of the environment radionuclides can be found in animal products. The main contamination pathways of domestic animas are: uptake of radionuclides by foodstuffs; uptake of radionuclides by contaminated drinking water; uptake of radionuclides by inhalation; uptake of radionuclides through skin; uptake of radionuclides by ingestion of soil particles. Generally the uptake of radionuclides by food is the dominant exposure pathway. In rare cases the inhalation of radionuclides or the uptake by drinking water may be of importance. The metabolism of incorporated radionuclides is comparable to the respective metabolism of essential mass or trace elements or heavy metals. Radioisotopes of essential elements are for instance iron 55, manganese 54, cobalt 58 and cobalt 60. Other elements are typical antagonists to essential elements, e.g. strontium 90 is an antagonist to calcium or cesium 137 to potassium. Lead 210 and plutonium 239 behave similarly as heavy metals. Generally the knowledge of the metabolism of trace and mass elements, of antagonistic and synergistic elements and heavy metals can be applied to these radionuclides

Radionuclide scanning

International Nuclear Information System (INIS)

Shapiro, B.

1986-01-01

Radionuclide scanning is the production of images of normal and diseased tissues and organs by means of the gamma-ray emissions from radiopharmaceutical agents having specific distributions in the body. The gamma rays are detected at the body surface by a variety of instruments that convert the invisible rays into visible patterns representing the distribution of the radionuclide in the body. The patterns, or images, obtained can be interpreted to provide or to aid diagnoses, to follow the course of disease, and to monitor the management of various illnesses. Scanning is a sensitive technique, but its specificity may be low when interpreted alone. To be used most successfully, radionuclide scanning must be interpreted in conjunction with other techniques, such as bone radiographs with bone scans, chest radiographs with lung scans, and ultrasonic studies with thyroid scans. Interpretation is also enhanced by providing pertinent clinical information because the distribution of radiopharmaceutical agents can be altered by drugs and by various procedures besides physiologic and pathologic conditions. Discussion of the patient with the radionuclide scanning specialist prior to the study and review of the results with that specialist after the study are beneficial

The europium and praseodymium hydrolysis in a 2M NaCl environment; La hidrolisis del europio y del praseodimio en un medio 2M de NaCl

Energy Technology Data Exchange (ETDEWEB)

Jimenez R, M.; Lopez G, H.; Solache R, M.; Rojas H, A. [Instituto Nacional de Investigaciones Nucleares, Departamento de quimica, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

1998-07-01

It was studied the europium and praseodymium hydrolysis in a 2M NaCl ion force environment at 303 K, through two methods: this one extraction with dissolvents (lanthanide-water-NaCl-dibenzoylmethane) in presence of a competitive ligand (diglycolic acid) and that one direct potentiometric titration, of soluble species, followed by a computer refining. The values of one or another techniques of the first hydrolysis constants obtained were similar, which demonstrates that the results are reliable. The set of data obtained on the stability constants of hydrolysis products allowed to draw up the distribution diagrams of chemical species, as europium as praseodymium in aqueous environment. (Author)

Traces of natural radionuclides in animal food

Energy Technology Data Exchange (ETDEWEB)

Merli, Isabella Desan; Guazzelli da Silveira, Marcilei A. [Centro Universitário da FEI, São Bernardo do Campo (Brazil); Medina, Nilberto H. [Instituto de Física da USP, São Paulo (Brazil)

2014-11-11

Naturally occurring radioactive materials are present everywhere, e.g., in soil, air, housing materials, food, etc. Therefore, human beings and animals receive internal exposure from radioactive elements inside their bodies through breathing and alimentation. Gamma radiation has enough energy to remove an electron from the atom and compromise the rearrangement of electrons in the search for a more stable configuration which can disturb molecule chemical bonding. Food ingestion is one of the most common forms of radioisotopes absorption. The goal of this work is the measurement of natural gamma radiation rates from natural radioisotopes present in animal food. To determine the concentration of natural radionuclides present in animal food gamma-ray spectrometry was applied. We have prepared animal food samples for poultry, fish, dogs, cats and cattle. The two highest total ingestion effective doses observed refers to a sample of mineral salt cattle, 95.3(15) μSv/year, rabbit chow, with a value of 48(5) μSv/year, and cattle mineral salt, with a value of 69(7) μSv/year, while the annual total dose value from terrestrial intake radionuclide is of the order of 290 μSv/year.

Traces of natural radionuclides in animal food

Science.gov (United States)

Merli, Isabella Desan; da Silveira, Marcilei A. Guazzelli; Medina, Nilberto H.

2014-11-01

Naturally occurring radioactive materials are present everywhere, e.g., in soil, air, housing materials, food, etc. Therefore, human beings and animals receive internal exposure from radioactive elements inside their bodies through breathing and alimentation. Gamma radiation has enough energy to remove an electron from the atom and compromise the rearrangement of electrons in the search for a more stable configuration which can disturb molecule chemical bonding. Food ingestion is one of the most common forms of radioisotopes absorption. The goal of this work is the measurement of natural gamma radiation rates from natural radioisotopes present in animal food. To determine the concentration of natural radionuclides present in animal food gamma-ray spectrometry was applied. We have prepared animal food samples for poultry, fish, dogs, cats and cattle. The two highest total ingestion effective doses observed refers to a sample of mineral salt cattle, 95.3(15) μSv/year, rabbit chow, with a value of 48(5) μSv/year, and cattle mineral salt, with a value of 69(7) μSv/year, while the annual total dose value from terrestrial intake radionuclide is of the order of 290 μSv/year.

Traces of natural radionuclides in animal food

International Nuclear Information System (INIS)

Merli, Isabella Desan; Guazzelli da Silveira, Marcilei A.; Medina, Nilberto H.

2014-01-01

Naturally occurring radioactive materials are present everywhere, e.g., in soil, air, housing materials, food, etc. Therefore, human beings and animals receive internal exposure from radioactive elements inside their bodies through breathing and alimentation. Gamma radiation has enough energy to remove an electron from the atom and compromise the rearrangement of electrons in the search for a more stable configuration which can disturb molecule chemical bonding. Food ingestion is one of the most common forms of radioisotopes absorption. The goal of this work is the measurement of natural gamma radiation rates from natural radioisotopes present in animal food. To determine the concentration of natural radionuclides present in animal food gamma-ray spectrometry was applied. We have prepared animal food samples for poultry, fish, dogs, cats and cattle. The two highest total ingestion effective doses observed refers to a sample of mineral salt cattle, 95.3(15) μSv/year, rabbit chow, with a value of 48(5) μSv/year, and cattle mineral salt, with a value of 69(7) μSv/year, while the annual total dose value from terrestrial intake radionuclide is of the order of 290 μSv/year

Drift-Scale Radionuclide Transport

International Nuclear Information System (INIS)

Houseworth, J.

2004-01-01

The purpose of this model report is to document the drift scale radionuclide transport model, taking into account the effects of emplacement drifts on flow and transport in the vicinity of the drift, which are not captured in the mountain-scale unsaturated zone (UZ) flow and transport models ''UZ Flow Models and Submodels'' (BSC 2004 [DIRS 169861]), ''Radionuclide Transport Models Under Ambient Conditions'' (BSC 2004 [DIRS 164500]), and ''Particle Tracking Model and Abstraction of Transport Process'' (BSC 2004 [DIRS 170041]). The drift scale radionuclide transport model is intended to be used as an alternative model for comparison with the engineered barrier system (EBS) radionuclide transport model ''EBS Radionuclide Transport Abstraction'' (BSC 2004 [DIRS 169868]). For that purpose, two alternative models have been developed for drift-scale radionuclide transport. One of the alternative models is a dual continuum flow and transport model called the drift shadow model. The effects of variations in the flow field and fracture-matrix interaction in the vicinity of a waste emplacement drift are investigated through sensitivity studies using the drift shadow model (Houseworth et al. 2003 [DIRS 164394]). In this model, the flow is significantly perturbed (reduced) beneath the waste emplacement drifts. However, comparisons of transport in this perturbed flow field with transport in an unperturbed flow field show similar results if the transport is initiated in the rock matrix. This has led to a second alternative model, called the fracture-matrix partitioning model, that focuses on the partitioning of radionuclide transport between the fractures and matrix upon exiting the waste emplacement drift. The fracture-matrix partitioning model computes the partitioning, between fractures and matrix, of diffusive radionuclide transport from the invert (for drifts without seepage) into the rock water. The invert is the structure constructed in a drift to provide the floor of the

Removal of radon by aeration: testing of various aeration techniques for small water works. For European Commission under Contract No FI4PCT960054 TENAWA project

International Nuclear Information System (INIS)

Salonen, L.; Mehtonen, J.; Turunen, H.; Mjoenes, L.; Hagberg, N.; Raff, O.

2002-12-01

Capability of various aeration techniques to remove radon from water in small waterworks was studied as a part of project (Treatment Techniques for Removing Natural Radionuclides from Drinking Water), which was carried out during 1997-1999 on a cost-shared basis (contract No. F14PCT960054) with The European Commission (CEC) under the supervision of the Directorate-General XII Radiation Protection Research Unit. In TENAWA project both laboratory and field experiments were performed in order to find reliable methods and equipment for removing natural radionuclides from ground water originating either from private wells or small waterworks. Because such techniques are more often needed in private households than at waterworks, the main emphasis of the research was aimed to solve the water treatment problems related to the private water supplies, especially bedrock wells. Radon was the most important radionuclide to be removed from water at waterworks whereas the removal of other radionuclides ( 234,238 U, 226,228 Ra, 210 Pb and 210 Po) was oft required from radonrich bedrock waters. The currently available methods and equipment were mainly tested during the field and laboratory experiments but the project was also aimed to find new materials, absorbents and membranes applicable for radionuclide removal from various types of ground waters (e.g. soft, hard, acidic). Because iron, manganese or organic occur in waters with radionuclides, their simultaneous removal was also studied. The project was divided into 13 work packages. In this report the results of the work package 2.2 are described. Elevated levels of radon and other natural radionuclides in European ground waters have been observed mainly in wide areas of the crystalline Scandinavian bedrock, especially in the granite rock areas of Finland and Sweden but also in more limited crystalline rock areas of Central and Southern Europe, Ukraine and Scotland. The radon removal efficiencies of different aeration methods

Chapter 2. Radionuclides in the biosphere

International Nuclear Information System (INIS)

Toelgyessy, J.; Harangozo, M.

2000-01-01

This is a chapter of textbook of radioecology for university students. In this chapter authors deal with role of radionuclides in the biosphere. Chapter consists of next parts: (1) Natural radionuclides in biosphere; (2) Man-made radionuclides in the biosphere; (3) Ecologically important radionuclides; (4) Natural background; (5) Radiotoxicity and (6) Paths of transfer of radionuclides from the source to human

Spectroscopic investigation on europium doped heavy metal borate glasses for red luminescent application

Energy Technology Data Exchange (ETDEWEB)

Hegde, Vinod; Wagh, Akshatha; Kamath, Sudha D. [Manipal University, Department of Physics, Manipal Institute of Technology, Manipal (India); Hegde, Hemanth [Manipal University, Department of Chemistry, Manipal Institute of Technology, Manipal (India); Vishwanath, C.S.D. [Sri Venkateswara University, Department of Physics, Tirupati (India)

2017-05-15

The present study explores a new borate family glasses based on 10ZnO-5Na{sub 2}O-10Bi{sub 2}O{sub 3}-(75 - x) B{sub 2}O{sub 3}-xEu{sub 2}O{sub 3} (x = 0, 0.1, 0.5, 1, 1.5, 2, 3 mol%) composition, synthesized by rapid melt quench technique. Prepared glasses were subjected to the density and refractive index measurements and their values were used to calculate other physical properties of the glass matrix as a function of Eu{sup 3+} concentration. XRD confirmed amorphous nature of the glasses. FTIR spectra in the absorption mode were recorded in the 400-4000 cm{sup -1} region to identify different functional groups in the glass matrix. Deconvoluted FTIR spectra showed increase in BO{sub 4} units with rise in europium content which confirmed the 'network strengthener' role of europium ions by creating bridging oxygens (BOs). Optical properties were investigated for their luminescence behavior through various spectroscopic techniques such as UV-Vis-NIR absorption, excitation, emission, decay profiles, and color measurements at room temperature. Lasing properties of the glasses like total radiative life time, branching ratio, emission cross section, and optical gain were obtained from the calculated Judd-Ofelt (Ω{sub 2},Ω{sub 4}) intensity parameters. From the measured values of emission, cross sections, branching ratios, life times, strong photoluminescence features, and CIE chromaticity coordinates, 0.5 mol% of Eu{sup 3+} ions doped ZnNaBiB glasses showed optimum performance and are potential candidate for red light generation at 613 nm. (orig.)

Processes for Removal and Immobilization of 14C, 129I, and 85Kr

Energy Technology Data Exchange (ETDEWEB)

Strachan, Denis M.; Bryan, Samuel A.; Henager, Charles H.; Levitskaia, Tatiana G.; Matyas, Josef; Thallapally, Praveen K.; Scheele, Randall D.; Weber, William J.; Zheng, Feng

2009-10-05

This is a white paper covering the results of a literature search and preliminary experiments on materials and methods to remove and immobilize gaseous radionuclided that come from the reprocessing of spent nuclear fuel.

Processes for Removal and Immobilization of 14C, 129I, and 85Kr

International Nuclear Information System (INIS)

Strachan, Denis M.; Bryan, Samuel A.; Henager, Charles H.; Levitskaia, Tatiana G.; Matyas, Josef; Thallapally, Praveen K.; Scheele, Randall D.; Weber, William J.; Zheng, Feng

2009-01-01

This is a white paper covering the results of a literature search and preliminary experiments on materials and methods to remove and immobilize gaseous radionuclides that come from the reprocessing of spent nuclear fuel.

Demonstration of radionuclides removal at the 105-N basin using the 3M system

International Nuclear Information System (INIS)

Hobart, S.A.; Hyman, M.

1996-03-01

A field demonstration of the Minnesota Mining and Manufacturing Company (3M) innovative Cs- and Sr-removal technology was undertaken to support deactivation of the Hanford Site's N Reactor. The field demonstration and laboratory studies performed by Pacific Northwest National Laboratory are documented in this report. The deactivation of N Reactor includes an aggressive schedule for removing water from the reactor's original fuel storage pool, known as N Basin. The plan for treating N Basin water involves particulate filtration, followed by further treatment at the Hanford Site's Effluent Treatment Facility (ETF) before the water is discharged to a permitted soil column. Prudence calls for developing a backup treatment plan in the event that ETF is not available to support the N Basin critical path schedule. The 3M technique uses membrane filters that are impregnated with chemical species to remove specific ions from water by ion exchange or selective reaction. Sodium titanate is used to remove Sr by ion exchange, and potassium-cobalt hexacyanoferrate (COHEX) is used to remove Cs by formation of cesium-cobalt ferrocyanide. As a result of this field test, the following recommendations are made: 3M technology should not be considered for removing Sr from N Basin water, although the technology merits consideration for Sr removal in waters that have relatively low Cs content; application of 3M technology by recirculation of basin water through 3M adsorption cartridges for removal of Cs-137 should be considered since it efficiently removes Cs and may be cost effective; additional pilot-scale tests should be performed to determine the capacity of COHEX for Cs-137 removal, if full-scale application is desired

Biomass selection for biosorption study of 226 Ra and 137 Cd radionuclides

International Nuclear Information System (INIS)

Costa, Wilson Cervi da

2003-01-01

The main goal of this work was to verify the potentialities to apply the biosorption technique to synthetic and real solution containing 226 Ra and 137 Cs, utilizing the seaweed Sargassum sp. and the microorganisms Penicillium sp., Saccharomyces cerevisiae and Monoraphidium sp. Indeed, the screening of the most effective biomass to remove the radionuclides was also a central objective. 226 Ra was selected due to its high radiotoxicity and the fact that it can be assimilated and incorporated by living organism through substitution og Mg 2+ and Ca 2+ , two essential nutrients. On the other hand, the selection of 137 Cs, a radionuclide of medium toxicity, was due to its mobility in the environment, which increases the possibility to be assimilated by the organisms as the essential nutrients Na + and K + . (author)

Competitive effect of metallic canister and clay barrier on the sorption of Eu3+ under subcritical conditions

International Nuclear Information System (INIS)

El Mrabet, Said; Castro, Miguel A.; Orta, M. Mar; Pazos, M. Carolina; Alba, Maria D.; Astudillo, Julio; Rueda, Silvia; Hurtado, Santiago; Villa, Mara

2012-01-01

Document available in extended abstract form only. The disposal of high level radioactive wastes (HLW) such as spent fuel or reprocessing waste resulting from the operation and dismantling of nuclear reactors is one of the most problems facing the worlds because of its long half life and radionuclide migration to the biosphere. For long term performance assessment of radioactive waste disposal, knowledge concerning radionuclide retention processes on materials composing the engineered barrier (clay and container waste) is required. Steel waste containers and bentonite have been proposed as candidate materials for overpack and buffer respectively in most of the proposed repositories designs for nuclear waste disposal. This contribution aims to study the competitiveness of the bentonite and the metallic canister in the retention process of some kinds of radioactive waste such as 152 Eu. The europium was chosen because it is a toxic metal and usually taken as a simulator of the trivalent high level radioactive waste. In order to elucidate the mechanisms involved in the retention processes of europium by both bentonite and metallic canister, a cylindrical steel mini-reactor was designed and prepared from the same material as the steel reactor AISI-316L. The bentonite was then introduced and compacted within the mini-reactor forming a set mini-reactor- bentonite. The system mini-reactor -bentonite was then subjected to hydrothermal treatments at 300 deg. C for 4.5 days. The morphology and chemical composition of both steel and bentonite were analyzed by XRD and SEM. SEM and XRD results revealed that both the bentonite and the metallic canister were involved in sorption mechanism of europium by the formation of insoluble phases of europium silicates originated from the mixed solution of bentonite, Eu 3+ and canister. The pH-Redox potential (Eh) indicated that the interlayer cations of bentonite were replaced by Eu 3+ with higher acidity and Eh which means that the active

Uranium removal from the water supply

International Nuclear Information System (INIS)

Miranzadeh, Mohammad Bagher.

1996-01-01

Uranium can be naturally occurring radionuclides that contaminate some potable water supplies. Uranium is found both in surface water and ground water supplies. The United States Environmental Protection Agency recently proposed a maximum contaminant of 20 micro gram/liter for uranium because of concerns about its association with kidney disease and cancer. uranium can be removed from the supply by strong base anion-resin. Exhausted resin is regenerated by sodium chloride solution. (Author)

Geomorphological applications of environmental radionuclides

International Nuclear Information System (INIS)

Quine, T.A.; Walling, D.

1998-01-01

Geomorphologists have shown increasing interest in environmental radionuclides since pioneering studies by Ritchie and McHenry in the USA and Campbell, Longmore and Loughran in Australia. Environmental radionuclides have attracted this interest because they provide geomorphologists with the means to trace sediment movement within the landscape. They, therefore, facilitate investigation of subjects at the core of geomorphology, namely the rates and patterns of landscape change. Most attention has been focussed on the artificial radionuclide caesium-137 ( 137 Cs) but more recently potential applications of the natural radionuclides lead-210 ( 210 Pb) and beryllium-7( 7 Be) have been investigated (Walling et al., 1995; Wallbrink and Murray, 1996a, 1996b). The origin, characteristics and applications of these radionuclides are summarised. These radionuclides are of value as sediment tracers because of three important characteristics: a strong affinity for sediment; a global distribution and the possibility of measurement at low concentration. Geomorphological applications of environmental radionuclides provide unique access to detailed qualitative data concerning landscape change over a range of timescales

Effects of added dibutyl phosphate on the luminescent properties of europium tetrakis dibenzoylmethide triethylammonium

International Nuclear Information System (INIS)

Fontenot, Ross S.; Bhat, Kamala N.; Owens, Constance A.; Hollerman, William A.; Aggarwal, Mohan D.

2015-01-01

Since 2003, the authors have been pushing the boundaries on a special type of functional material, i.e., a material that gives off light when it is stressed, strained, and/or fractured. This unique class of materials has been proposed for the active element of impact sensors, earthquake detectors, and stress sensors. However, in order for this concept to go from the lab to real world applications, the light emission from these functional materials must be bright such that inexpensive light detectors can be used. One of the brightest materials found thus far is europium tetrakis dibenzoylmethide triethylammonium (EuD 4 TEA). This material has an emission so bright that it can be observed in daylight. In 2013, the authors discovered that the addition of dimethyl methylphosphonate (DMMP) increased the light emission two fold. As a result, a search for similar compounds was conducted to determine if the emission can be increased further. This paper explores the effects of dibutyl phosphate (DBP) on EuD 4 TEA. The effects of DBP on the triboluminescence, photoluminescence, and crystal structure of EuD 4 TEA will be determined. This paper will show that DBP has an even greater effect on the properties of EuD 4 TEA than DMMP. - Highlights: • Synthesized europium tetrakis dibenzoylmethide triethylammonium. • Six fold increase in the light yield was detected. • Effects of dibutyl phosphate on the triboluminescence on EuD 4 TEA were determined. • Effects of dibutyl phosphate on the photoluminescence of EuD 4 TEA were determined

Effects of added dibutyl phosphate on the luminescent properties of europium tetrakis dibenzoylmethide triethylammonium

Energy Technology Data Exchange (ETDEWEB)

Fontenot, Ross S., E-mail: rsfontenot@hotmail.com [Alabama A and M University, Department of Physics, Chemistry, and Mathematics, P.O. Box 1268, Normal, AL 35762 (United States); University of Louisiana at Lafayette, Department of Physics, P.O. Box 44210, Lafayette, LA 70504 (United States); Bhat, Kamala N.; Owens, Constance A. [Alabama A and M University, Department of Physics, Chemistry, and Mathematics, P.O. Box 1268, Normal, AL 35762 (United States); Hollerman, William A. [University of Louisiana at Lafayette, Department of Physics, P.O. Box 44210, Lafayette, LA 70504 (United States); Aggarwal, Mohan D. [Alabama A and M University, Department of Physics, Chemistry, and Mathematics, P.O. Box 1268, Normal, AL 35762 (United States)

2015-02-15

Since 2003, the authors have been pushing the boundaries on a special type of functional material, i.e., a material that gives off light when it is stressed, strained, and/or fractured. This unique class of materials has been proposed for the active element of impact sensors, earthquake detectors, and stress sensors. However, in order for this concept to go from the lab to real world applications, the light emission from these functional materials must be bright such that inexpensive light detectors can be used. One of the brightest materials found thus far is europium tetrakis dibenzoylmethide triethylammonium (EuD{sub 4}TEA). This material has an emission so bright that it can be observed in daylight. In 2013, the authors discovered that the addition of dimethyl methylphosphonate (DMMP) increased the light emission two fold. As a result, a search for similar compounds was conducted to determine if the emission can be increased further. This paper explores the effects of dibutyl phosphate (DBP) on EuD{sub 4}TEA. The effects of DBP on the triboluminescence, photoluminescence, and crystal structure of EuD{sub 4}TEA will be determined. This paper will show that DBP has an even greater effect on the properties of EuD{sub 4}TEA than DMMP. - Highlights: • Synthesized europium tetrakis dibenzoylmethide triethylammonium. • Six fold increase in the light yield was detected. • Effects of dibutyl phosphate on the triboluminescence on EuD{sub 4}TEA were determined. • Effects of dibutyl phosphate on the photoluminescence of EuD{sub 4}TEA were determined.

Foodstuffs, radionuclides, monitoring

International Nuclear Information System (INIS)

Denisikov, A.I.

2000-01-01

Radionuclide contamination of water and food stuffs as a result of the Chernobyl accident and permissible contents of 90 Sr and 137 Cs are considered in brief. A method of radiation monitoring of food stuffs and water for the radionuclides mentioned is suggested. The method permits employment of the simplest and cheapest radiometric equipment for analysis, whole the high degree of radionuclide concentration using fiber sorbents permits using the instrumentation without expensive shields against external radiation. A description of ion-exchange unit for radiation monitoring of liquid samples of food stuffs or water, is provided [ru

Process for encapsulating radionuclides

International Nuclear Information System (INIS)

Brownell, L.E.; Isaacson, R.E.

1976-01-01

Radionuclides are immobilized in virtually an insoluble form by reacting at a temperature of at least 90 0 C as an aqueous alkaline mixture having a solution pH of at least 10, containing a source of silicon, the radionuclide waste, and a metal cation. The molar ratio of silicon to the metal cation is on the order of unity to produce a gel from which complex metalosilicates crystallize to entrap the radionuclides within the resultant condensed crystal lattice. The product is a silicious stone-like material which is virtually insoluble and nonleachable in alkaline or neutral environment. One embodiment provides for the formation of the complex metalo-silicates, such as synthetic pollucite, by gel formation with subsequent calcination to the solid product; another embodiment utilizes a hydrothermal process, either above ground or deep within basalt caverns, at greater than atmospheric pressures and a temperature between 90 and 500 0 C to form complex metalo-silicates, such as strontium aluminosilicate. Another embodiment provides for the formation of complex metalo-silicates, such as synthetic pollucite, by slurrying an alkaline mixture of bentonite or kaolinite with a source of silicon and the radionuclide waste in salt form. In each of the embodiments a mobile system is achieved whereby the metalo-silicate constituents reorient into a condensed crystal lattice forming a cage structure with the condensed metalo-silicate lattice which completely surrounds the radionuclide and traps the radionuclide therein; thus rendering the radionuclide virtually insoluble

Simple preparation of fluorescent composite films based on cerium and europium doped LaF3 nanoparticles

Science.gov (United States)

Secco, Henrique de L.; Ferreira, Fabio F.; Péres, Laura O.

2018-03-01

The combination of materials to form hybrids with unique properties, different from those of the isolated components, is a strategy used to prepare functional materials with improved properties aiming to allow their application in specific fields. The doping of lanthanum fluoride with other rare earth elements is used to obtain luminescent particles, which may be useful to the manufacturing of electronic devices' displays and biological markers, for instance. The application of the powder of nanoparticles has limitations in some fields; to overcome this, the powder may be incorporated in a suitable polymeric matrix. In this work, lanthanum fluoride nanoparticles, undoped and doped with cerium and europium, were synthesized through the co-precipitation method in aqueous solution. Aiming the formation of solid state films, composites of nanoparticles in an elastomeric matrix, the nitrile rubber (NBR), were prepared. The flexibility and the transparency of the matrix in the regions of interest are advantages for the application of the luminescent composites. The composites were applied as films using the casting and the spin coating techniques and luminescent materials were obtained in the samples doped with europium and cerium. Scanning electron microscopy images showed an adequate dispersion of the particles in the matrix in both film formation techniques. Aggregates of the particles were detected in the samples which may affect the uniformity of the emission of the composites.

Speciation and bioaccumulation in a model organism of U, Np and Am in the marine environment

International Nuclear Information System (INIS)

Maloubier, Melody

2015-01-01

The fate of natural and anthropogenic radionuclides in the environment remains a major concern in our modern nuclearized societies. Among the environmental compartments, the hydrosphere is ubiquitous and can transport compounds or elements over very long distances. The recent event of Fukushima demonstrated that the marine environment could be directly affected and this raises both scientific and societal questions. Moreover, some studies have already shown that radionuclides present in seawater can be strongly accumulated by marine organisms although their speciation is most of the time unknown. Yet this knowledge is essential to better understand the transfer mechanisms from the hydrosphere to the biosphere and to evaluate their global impact on humans. In this work, we chose to experimentally determine the speciation of three actinides in doped seawater: uranium(VI), neptunium(V) and americium(III) (and the chemical surrogate europium(III)) by coupling speciation modeling with spectroscopic tools among which Time-Resolved Laser-Induced Fluorescence (TRLIF) and X-ray Absorption Spectroscopy (XAS). Then, we have studied the accumulation process in the sponge A. cavernicola, chosen here because it is considered as a bio-monitor of heavy metal pollution. The accumulation of europium(III), americium(III) and uranium(VI) in A. cavernicola were investigated at trace and ultra-trace levels. Besides, for europium, X-ray and electronic imaging permit to localize the accumulated element in the sponge and to specify its speciation [fr

New coordination compounds of europium (3) with fluorated β-diketones and their use as lanthanide shift reagents

International Nuclear Information System (INIS)

Goryushko, A.G.; Davidenko, N.K.; Kudryavtseva, L.S.; Lozinskij, M.O.; Lugina, L.N.; Fialkov, Yu.A.

1980-01-01

Altogether five coordination compounds of europium (3) of the composition EuL 3 , wherein HL is a fluorinated beta-diketone containing in its fluorinated linear or cyclic radical a heteroatom, such as oxygen, have been obtained. The hygroscopicity of the obtained tris-beta-ketones has been tested. Their activity as lanthanide shifting agents for NMR spectroscopy purposes has been analyzed and the stability constants of their monoadducts with ethyl acetate have been determined [ru

Spectral-luminescent investigation of polymers doped with europium trisphenoyltrifluoroacetonate compound with 1,10-phenanthroline

International Nuclear Information System (INIS)

Karasev, V.E.; Mirochnik, A.G.; Shchelokov, R.N.

1983-01-01

Spectral-luminescent characteristics of europium tristhenoyltrifluoroacetonate with 1.10-phenanthpoline in polystyrepe and polyvinyl chloride are investigated. E 4 (TTA) 3 phen during introduction into polymers preserves its composition and structure. Weak temperature dependence of half-Width of luminescent lines qualitatively different from the case of crystal chelate is characteristic for polymers doped with E 4 (TTA) 3 xphen. Investigation into temperature dependence of E 4 3+ luminescent intensity in chelate doped polymers proves the conclusion on weakening processes of excitation energy relaxation by vibration constituents of close and far environment during chelate introduction into polymers

A microemulsion preparation of nanoparticles of europium in silica with luminescence enhancement using silver

International Nuclear Information System (INIS)

Ma Zhiya; Dosev, Dosi; Kennedy, Ian M

2009-01-01

A facile one-pot microemulsion method has been developed for the synthesis of spherical silver core-silica shell (Ag-SiO 2 ) nanoparticles with europium chelates doped in the shell through a silane agent. The method is significantly more straightforward than other extant methods. Measurements of the luminescent emissions from the Ag-SiO 2 nanoparticles, in comparison with control silica nanoparticles without silver cores, showed that the presence of the silver cores can increase the fluorescence intensity approximately 24-fold and decrease the luminescence lifetime. This enhancement offers a potential increase in overall particle detectability with increased fluorophore photostability.

Removal of radionuclides from process streams, a series of applications

International Nuclear Information System (INIS)

Menetrez, M.Y.

1987-01-01

The extensive research performed on metal oxide adsorption, the adsorption phenomena and physical conditions of cationic adsorption on manganese dioxide in solution have demonstrated that above pH 3 cations are adsorbed by an order of affinity, and that the interaction is characterized by the pH dependence of the metal. The relationship of the zero point charge of pH and the solution ionic strength effects on interfacial surface potential and adsorption have been addressed. A system to produce MnO 2 fiber with a heavy MnO 2 loading was designed, constructed, and operated successfully. Extensive testing has been performed on the adsorption of radium, calcium, cadmium, cesium, cobalt, iron, and manganese on MnO 2 fiber. This testing entailed field work utilizing bleed stream tests of MnO 2 fiber cartridges and tests of loose MnO 2 fiber and resin in columns. Radium removal amounted to a level of 36.9 nanocuries per gram MnO 2 , or 2 microcuries on a single 10 inch MnO 2 fiber filter element. Removal of metals from solutions was demonstrated at various rates specific for each metal tested. The order of affinity of those metals tested and the combined effects of electrolytic solutions was compared to previous research. The analysis of radium in water was performed using a highly modified procedure which is included to specify the exact steps of the analytical method followed. This method has introduced innovations in equipment, technique, and the use of reagents. Results of a comparison of MnO 2 fiber to commercial water treatment media for the removal of cobalt and cesium is presented

Ventricular dysfunction in children with obstructive sleep apnea: radionuclide assessment

International Nuclear Information System (INIS)

Tal, A.; Leiberman, A.; Margulis, G.; Sofer, S.

1988-01-01

Ventricular function was evaluated using radionuclide ventriculography in 27 children with oropharyngeal obstruction and clinical features of obstructive sleep apnea. Their mean age was 3.5 years (9 months to 7.5 years). Conventional clinical assessment did not detect cardiac involvement in 25 of 27 children; however, reduced right ventricular ejection fraction (less than 35%) was found in 10 (37%) patients (mean: 19.5 +/- 2.3% SE, range: 8-28%). In 18 patients wall motion abnormality was detected. In 11 children in whom radionuclide ventriculography was performed before and after adenotonsillectomy, right ventricular ejection fraction rose from 24.4 +/- 3.6% to 46.7 +/- 3.4% (P less than 0.005), and in all cases wall motion showed a definite improvement. In five children, left ventricular ejection fraction rose greater than 10% after removal of oropharyngeal obstruction. It is concluded that right ventricular function may be compromised in children with obstructive sleep apnea secondary to adenotonsillar hypertrophy, even before clinical signs of cardiac involvement are present

Radionuclide transfer from mother to embryo

International Nuclear Information System (INIS)

Toader, M.; Vasilache, R.A.; Scridon, R.; Toader, M.L.

1998-01-01

The transfer of radionuclides from mother to embryo is still a matter of high interest. Therefore, the relation was investigated between the amount of radionuclides in the embryo and the dietary intake of the mother, this for two scenarios: a recurrent intake of variable amounts of radionuclides, and a long-term intake of a relatively constant amount of radionuclides, the radionuclide being 137 Cs. In the first case, the amount of radionuclides present in the embryo increases with the age of the embryo and with the intake of the mother. In the second case, no correlation could be found between the age of the embryo and its radioactive content; only the correlation between the intake of the mother and the radionuclide content of the embryo remained. (A.K.)

Residual radioactive contamination of the Maralinga range from nuclear weapons tests conducted in 1956 and 1957

International Nuclear Information System (INIS)

Cooper, M.B.; Duggleby, J.C.; Kotler, L.H.; Wise, K.N.

1978-12-01

Detailed geographical distributions and concentrations of long-lived radionuclides remaining from the major trials of nuclear weapons conducted at Maralinga in 1956 and 1957 are presented. It is shown that residual contamination due to fission products - mainly strontium-90, caesium-137 and europium-155 - are well below levels that could constitute a health hazard to occupants of the area. In the regions near the ground zeroes however, long-lived neutron activation products in soil - mainly cobalt-60 and europium-152 - are present in sufficient abundance to give rise to gamma-radiation dose-rates up to 2 milliroentgen per hour, which exceed maximum recommended dose-rates for continuous occupancy

Radionuclide diagnosis of emergency states

International Nuclear Information System (INIS)

Ishmukhametov, A.I.

1985-01-01

Solution of emergency state radionuclide diagnostics from the technical point of view is provided by the application of the mobile quick-operating equipment in combination with computers, by the use of radionuclides with acceptable for emergency medicine characteristics and by development of radionuclide investigation data propcessing express-method. Medical developments include the study of acute disease and injury radioisotope semiotics, different indication diagnostic value determining, comparison of the results, obtained during radionuclide investigation, with clinicolaboratory and instrumental data, separation of methodical complex series

Anthropogenic radionuclides in the environment

Energy Technology Data Exchange (ETDEWEB)

Hu, Q; Weng, J; Wang, J

2007-11-15

Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview of anthropogenic radionuclide contamination in the environment, as well as the salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current development that contribute to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) commercial fuel reprocessing; (5) geological repository of high-level nuclear wastes, and (6) nuclear accidents. Then, we summarize the geochemical behavior for radionuclides {sup 99}Tc, {sup 129}I, and {sup 237}Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment. Biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.

Radionuclide daughter inventory generator code: DIG

International Nuclear Information System (INIS)

Fields, D.E.; Sharp, R.D.

1985-09-01

The Daughter Inventory Generator (DIG) code accepts a tabulation of radionuclide initially present in a waste stream, specified as amounts present either by mass or by activity, and produces a tabulation of radionuclides present after a user-specified elapsed time. This resultant radionuclide inventory characterizes wastes that have undergone daughter ingrowth during subsequent processes, such as leaching and transport, and includes daughter radionuclides that should be considered in these subsequent processes or for inclusion in a pollutant source term. Output of the DIG code also summarizes radionuclide decay constants. The DIG code was developed specifically to assist the user of the PRESTO-II methodology and code in preparing data sets and accounting for possible daughter ingrowth in wastes buried in shallow-land disposal areas. The DIG code is also useful in preparing data sets for the PRESTO-EPA code. Daughter ingrowth in buried radionuclides and in radionuclides that have been leached from the wastes and are undergoing hydrologic transport are considered, and the quantities of daughter radionuclide are calculated. Radionuclide decay constants generated by DIG and included in the DIG output are required in the PRESTO-II code input data set. The DIG accesses some subroutines written for use with the CRRIS system and accesses files containing radionuclide data compiled by D.C. Kocher. 11 refs

FUTURE STUDIES AT PENA BLANCA: RADIONUCLIDE MIGRATION IN THE VADOSE ZONE OF AN ALLUVIAL FAN

Energy Technology Data Exchange (ETDEWEB)

P. Goodell; J. Walton; P.J. Rodriguez

2005-07-11

The pathway to the accessible environment at Yucca Mountain contains volcanic rocks and alluvial fill. Transport properties in alluvial fill, specifically retardation and dispersivity, may be significant in determining the overall performance of the repository. Prior relevant studies, with the exception of the Nye County Tracer Test, are almost entirely in bedrock material. The proposed study will provide field data on radionuclide migration in alluvial material. High grade uranium ore was mined at the Nopal I deposit. This mined ore (60,000 tons) was moved in 1994 to its present site as open piles on an alluvial fan in the Boquilla Colorada Microbasin. Precipitation is approximately 20 cm/year, and has caused migration of radionuclides into the subsurface. We propose partial removal of an ore pile, excavation into the alluvial fan, sampling, and determination of radionuclide mobilities from the uranium decay chain. The proposed research would be taking advantage of a unique opportunity with a known time frame for migration.

FUTURE STUDIES AT PENA BLANCA: RADIONUCLIDE MIGRATION IN THE VADOSE ZONE OF AN ALLUVIAL FAN

International Nuclear Information System (INIS)

Goodell, P.; Walton, J.; Rodriguez, P.J.

2005-01-01

The pathway to the accessible environment at Yucca Mountain contains volcanic rocks and alluvial fill. Transport properties in alluvial fill, specifically retardation and dispersivity, may be significant in determining the overall performance of the repository. Prior relevant studies, with the exception of the Nye County Tracer Test, are almost entirely in bedrock material. The proposed study will provide field data on radionuclide migration in alluvial material. High grade uranium ore was mined at the Nopal I deposit. This mined ore (60,000 tons) was moved in 1994 to its present site as open piles on an alluvial fan in the Boquilla Colorada Microbasin. Precipitation is approximately 20 cm/year, and has caused migration of radionuclides into the subsurface. We propose partial removal of an ore pile, excavation into the alluvial fan, sampling, and determination of radionuclide mobilities from the uranium decay chain. The proposed research would be taking advantage of a unique opportunity with a known time frame for migration

Critical review: Radionuclide transport, sediment transport, and water quality mathematical modeling; and radionuclide adsorption/desorption mechanisms

Energy Technology Data Exchange (ETDEWEB)

Onishi, Y.; Serne, R.J.; Arnold, E.M.; Cowan, C.E.; Thompson, F.L. [Pacific Northwest Lab., Richland, WA (United States)

1981-01-01

This report describes the results of a detailed literature review of radionuclide transport models applicable to rivers, estuaries, coastal waters, the Great Lakes, and impoundments. Some representatives sediment transport and water quality models were also reviewed to evaluate if they can be readily adapted to radionuclide transport modeling. The review showed that most available transport models were developed for dissolved radionuclide in rivers. These models include the mechanisms of advection, dispersion, and radionuclide decay. Since the models do not include sediment and radionuclide interactions, they are best suited for simulating short-term radionuclide migration where: (1) radionuclides have small distribution coefficients; (2) sediment concentrations in receiving water bodies are very low. Only 5 of the reviewed models include full sediment and radionuclide interactions: CHMSED developed by Fields; FETRA SERATRA, and TODAM developed by Onishi et al, and a model developed by Shull and Gloyna. The 5 models are applicable to cases where: (1) the distribution coefficient is large; (2) sediment concentrations are high; or (3) long-term migration and accumulation are under consideration. The report also discusses radionuclide absorption/desorption distribution ratios and addresses adsorption/desorption mechanisms and their controlling processes for 25 elements under surface water conditions. These elements are: Am, Sb, C, Ce, Cm, Co, Cr, Cs, Eu, I, Fe, Mn, Np, P, Pu, Pm, Ra, Ru, Sr, Tc, Th, {sup 3}H, U, Zn and Zr.

Further investigations on removal of 134,137Cs from animal meat

International Nuclear Information System (INIS)

Il'enko, A.I.; Krapivko, T.P.

1992-01-01

This paper deals with the process of removing cesium radionuclides from the meat of ungulates and fish. The fish, boar and moose were contaminated after the 1986 accident at Chernobyl. The premise of this experiment was that saturation of the deactivating solution with potassium, a chemical analog of cesium, or with an absorbent such as kaolin, would promote faster and more complete washing out of radionuclides from the object to be deactivated. The conclusions reached were that increasing the frequency of changing the deactivating solution reduces with total deactivation time for the meat of ungulates, as well as for fish by almost two times. Moose meat is easier to deactivate that boar meat. The addition of potassium KMnO 4 to the basic solution significantly accelerates washing out of cesium radionuclides. Also, preliminary freezing of fish significantly increases the effectiveness of deactivation

Chitosan-ferrocyanide sorbent for Cs-137 removal from mineralized alkaline media

Energy Technology Data Exchange (ETDEWEB)

Egorin, Andrei [Far Eastern Federal Univ., Vladivostok (Russian Federation); Institute of Chemistry FEBRAS, Vladivostok (Russian Federation); Ozyorsk Technical Institute MEPHI, Ozersk (Russian Federation); Tokar, Eduard [Far Eastern Federal Univ., Vladivostok (Russian Federation); Zemskova, Larisa [Institute of Chemistry FEBRAS, Vladivostok (Russian Federation)

2016-11-01

An organomineral sorbent based on mixed nickel-potassium ferrocyanide and chitosan to be used in removal of Cs-137 radionuclide from highly mineralized media with high pH has been fabricated. The synthesized sorbent was applied to remove Cs-137 from model solutions under static and dynamic conditions. The effects of contact time, pH, and presence of sodium ions and complexing agents in the process of Cs-137 removal have been investigated. The sorbent is distinguished by increased stability to the impact of alkaline media containing complexing agents, whereas the sorbent capacity in solutions with pH 11 exceeds 1000 bed volumes with the Cs-137 removal efficiency higher than 95%.

Feasibility Assessment of Cesium Removal using Microaglae

Energy Technology Data Exchange (ETDEWEB)

Kim, Ilgook; Ryu, Byung-Gon; Seo, Bum-Kyoung; Moon, Jei Kwon; Choi, Jong-Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

The aim of this work is to assess the feasibility of selected one of microalgae in the uptake of Cs+. The obtained results showed the maximum Cs+ removal by D. armatus SCK was 280μM indicating 70% removal efficiency. Also, D. armatus SCK could uptake Cs+ in the presence of K+, is particularly known to be transported into cells as an analog of Cs+ in freshwater condition. Recently, increased attention has been directed on the use of biological technologies for the removal of radionuclides as the cheap and eco-friendly alternative to the non-biological methods. Metal including radioactive compounds uptake by microorganisms can be occurred by metabolism –independent and/or -dependent processes. One involves biosorption based on the ability of microbial cells to bind dissolved metals; on the other involves bioaccumulation, which depends on the metabolic ability of cells to transport metals into the cytoplasm. The purpose of this work is to investigate the feasibility of microalgae in bioaccumulation system to remove cesium from solution. The effect of different environmental parameters on cesium removal was also examined.

Technical basis for internal dosimetry at Hanford

Energy Technology Data Exchange (ETDEWEB)

Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

1991-07-01

The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products ({sup 58}Co, {sup 60}Co, {sup 54}Mn, and {sup 59}Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium,. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation and bioassay follow-up treatment. 78 refs., 35 figs., 115 tabs.

Technical basis for internal dosimetry at Hanford

Energy Technology Data Exchange (ETDEWEB)

Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

1989-04-01

The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products (/sup 58/Co, /sup 60/Co, /sup 54/Mn, and /sup 59/Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation; and bioassay follow-up treatment. 64 refs., 42 figs., 118 tabs.

Technical basis for internal dosimetry at Hanford

International Nuclear Information System (INIS)

Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

1991-07-01

The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products ( 58 Co, 60 Co, 54 Mn, and 59 Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium,. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation and bioassay follow-up treatment. 78 refs., 35 figs., 115 tabs

Technical basis for internal dosimetry at Hanford

International Nuclear Information System (INIS)

Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

1989-04-01

The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products ( 58 Co, 60 Co, 54 Mn, and 59 Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation; and bioassay follow-up treatment. 64 refs., 42 figs., 118 tabs

Tuning Eu"3"+ emission in europium sesquioxide films by changing the crystalline phase

International Nuclear Information System (INIS)

Mariscal, A.; Quesada, A.; Camps, I.; Palomares, F.J.; Fernández, J.F.; Serna, R.

2016-01-01

Highlights: • PLD production of high quality europium sesquioxide (Eu_2O_3) films. • The deposition of Al_2O_3 capping and/or buffer layers modifies the crystallization for Eu_2O_3 films upon annealing. • The formation of cubic or monoclinic phases can be favored. • Eu"3"+ emission tuning is achieved as a consequence of crystal field effects. - Abstract: We report the growth of europium sesquioxide (Eu_2O_3) thin films by pulsed laser deposition (PLD) in vacuum at room temperature from a pure Eu_2O_3 ceramic bulk target. The films were deposited in different configurations formed by adding capping and/or buffer layers of amorphous aluminum oxide (a-Al_2O_3). The optical properties, refractive index and extinction coefficient of the as deposited Eu_2O_3 layers were obtained. X-ray photoelectron spectroscopy (XPS) measurements were done to assess its chemical composition. Post-deposition annealing was performed at 500 °C and 850 °C in air in order to achieve the formation of crystalline films and to accomplish photoluminescence emission. According to the analysis of X-ray diffraction (XRD) spectra, cubic and monoclinic phases were formed. It is found that the relative amount of the phases is related to the different film configurations, showing that the control over the crystallization phase can be realized by adequately designing the structures. All the films showed photoluminescence emission peaks (under excitation at 355 nm) that are attributed to the intra 4f-transitions of Eu"3"+ ions. The emission spectral shape depends on the crystalline phase of the Eu_2O_3 layer. Specifically, changes in the hypersensitive "5D_0 → "7F_2 emission confirm the strong influence of the crystal field effect on the Eu"3"+ energy levels.

The Magnetic Response of Europium Implanted in Cerium and in Platinum as Investigated by the PAC-Method

International Nuclear Information System (INIS)

Zeitz, W.-D.; Unterricker, S.; Schneider, F.; Samokhvalov, V.; Potzger, K.; Weber, A.; Dietrich, M.

2004-01-01

The magnetic response of europium in γ-cerium and in platinum was studied by applying the perturbed angular correlation spectroscopy. The probe nuclei were 147 Eu(11/2 - ) and 149 Eu(11/2 - ). The response in γ-Ce was determined by the electronic S = J = 7/2 ground state of divalent Eu. In Pt, on the other hand, Eu is trivalent (J = 0 ground state). Here the magnetic contributions originate from Van Vleck terms of the whole multiplet system.

Affinity of hydroxyapatite by radionuclides parent/child in 188Re/188W generator for radiotherapy

International Nuclear Information System (INIS)

Carrera D, A. A.; Badillo A, V.; Badillo A, V. E.; Monroy G, F.

2009-10-01

To assess the feasibility of using apatites as matrices of 188 W/ 188 Re generator is essential to obtain the distribution coefficients as much of parent radionuclide as child radionuclide in apatite, that is to say to know their affinity for the solid. It was selected the mineral species more representative as adsorbent, the hydroxyapatite Ca 10 (PO 4 ) 6 (OH) 2 it is known for its great capacity of ions retention and by presenting a large affinity for anionic species in their surface. In this paper we use a synthetic hydroxyapatite marketed by Bio-Rad. This paper presents the preliminary results regarding the affinity of hydroxyapatite for the anionic species tungstates (WO 4 2- ) and perrhenates (ReO 4 - in EDTA, as background electrolyte expressed as distribution coefficients between two immiscible phases obtained with the help of radioactive tracers 187 W and 188 Re respectively. The retention measures of these ions, traces show that Bio-Gel hydroxyapatite presents moderate values of distribution coefficients for anionic species of W(Vi) in EDTA 0.01 mol/L that are in the range p H 5 to 6.5; the parent radionuclide of generator 188 Re/ 188 W is fixed but not enough to consider it a good absorbent. By contrast, the fixation of perrhenate ions is virtually wiped as may be easily removed from a hydroxyapatite column packed with a saline solution. The influence of this saline solution in the removal of perrhenate ions is null practically. (Author)

IVO's nuclide removal system takes to the road

International Nuclear Information System (INIS)

Tusa, E.H.

1995-01-01

The successful and routine use of IVO's treatment system for the removal of cesium from the evaporator concentrates at the Loviisa WER plant in Finland is described. The system uses a granular inorganic hexacyanoferate-based ion exchanger to separate cesium from liquid radioactive wastes. The compactness of the original systems at Loviisa suggested the development of a transportable unit. A combined nuclide removal system was created which included a highly efficient ultrafiltration unit to separate nearly all particulate material carrying radionuclides, as well as the cesium removal capability. A 20ft long container carrying the removal package was completed in 1994. This NUclide REmoval System (NURES) was used for the first time in January 1995 to purify liquid waste accumulating at training reactors in Estonia and has performed well. As an extension of nuclide removal, a process has been created to recover boron from liquid wastes. A system for boron recovery and nuclide removal has been designed for use at the Paks plant in Hungary. The removal process has been shown to improve the safety of final waste disposal compared with the alternative treatment by cementation because the cesium is very tightly bound into the ion exchange material. (UK)

Treatment of heavy metals and radionuclides in groundwater and wastewater by magnetic separation

International Nuclear Information System (INIS)

Bradbury, D.; Elder, G.R.; Tucker, P.M.; Dunn, M.J.

1992-01-01

Removal of trace quantities of heavy metal or radionuclide contamination from solutions at high flow rate presents a considerable technical challenge. Low flow methods of treatment such as particle gravity settling require expensive large volume equipment, whereas traditional methods of filtration demand significant energy costs. Magnetic filtration can be used to provide a low cost method of solid-liquid separation at high flow rate, provided contaminants can be selectively bound to a magnetic solid particle. This paper describes recent progress with this technique including performance tests of composite materials produced to selectively remove specific contaminants such as cesium, uranium, lead, cadmium, and mercury from solution

History of medical radionuclide production.

Science.gov (United States)

Ice, R D

1995-11-01

Radionuclide production for medical use originally was incidental to isotope discoveries by physicists and chemists. Once the available radionuclides were identified they were evaluated for potential medical use. Hevesy first used 32P in 1935 to study phosphorous metabolism in rats. Since that time, the development of cyclotrons, linear accelerators, and nuclear reactors have produced hundreds of radionuclides for potential medical use. The history of medical radionuclide production represents an evolutionary, interdisciplinary development of applied nuclear technology. Today the technology is represented by a mature industry and provides medical benefits to millions of patients annually.

Resorption of radionuclides through the surface of thermal burns and problems of decontamination

International Nuclear Information System (INIS)

Il'in, L.A.; Ivannikov, A.T.; Popov, B.A.; Parfenova, I.M.

1981-01-01

Resorption of sup(137)Cs, sup(89)Sr, sup(131)I, sup(241)Am during thermal burns of 1-3 degrees and choice of a decontamination method used simultaneously for decontamination and disinfection of burn wounds were studied. It is shown that a degree of burns effects in a certain form on skin penetrability: through burns of 1-2 degrees the resorption increases 1 5-3 times, through burns of the thir degree the resorption decreases slightly as compared to the resorption through intact skin. High efficiency of 3% soap solution for removing radionuclides from burn csurfae of skin has been established. For burns accompanied with the disturbance of epidermis integrality, when considerable absorption of radionuclides is possible, decontamination must be accomplished as soon and complete as possible [ru

Effects of water treatment processes used at waterworks on natural radionuclide concentrations

International Nuclear Information System (INIS)

Haemaelaeinen, K.; Vesterbacka, P.; Maekelaeinen, I.; Arvela, H.

2004-08-01

The occurrence of uranium and other natural radionuclides in waters of waterworks and the effects of the conventional water treatment processes on radionuclide concentrations were investigated. Water samples were collected from 17 waterworks. Radionuclide concentrations of the collected samples were compared to the currently valid concentrations according to the Finnish regulation, ST guide 12.3. Similarly the measured concentrations were compared to the values presented in the 98/83/EC directive and in the Commission recommendation, 2001/928/Euratom. The guidelines based on chemical toxicity of uranium were also considered. This report presents a summary of the radionuclide concentrations in waters distributed by waterworks. Short-term and logn-term temporal variation of radionuclide levels in raw water were also investigated. Waterworks selected to this study used different kinds of raw water sources and a variety of water treatment processes. Water samples were collected from 46 water catchments which used groundwater in soil, artificial groundwater or groundwater in bedrock as a source of raw water. The most common water treatment used in these catchments was alkalization. Other treatment processes used were various types of filtrations (sand, anthracite, slow sand and membrane filtration) and aeration. Four of the catchments distributed water without treatment. Sampling was carried out in co-operation with local health inspectors and waterworks staff in spring 2002. Later that autumn, monitoring samples were collected from eight catchments. The maximum value for radon, presented in ST guide 12.3, was exceeded in three water catchments that used groundwater in bedrock as a source of raw water. No exceedings were found in those water catchments that use groundwater in soil or artificial groundwater. The limits of uranium and radium calculated from the total indicative dose (98/83/EC) were not exceeded but the guidelines for lead and polonium, given in the

Transfer of fallout radionuclides derived from Fukushima NPP accident: 1 year study on transfer of radionuclides through hydrological processes

Science.gov (United States)

Onda, Yuichi; Kato, Hiroaki; Patin, Jeremy; Yoshimura, Kazuya; Tsujimura, Maki; Wakahara, Taeko; Fukushima, Takehiko

2013-04-01

Previous experiences such as Chernobyl Nuclear Power Plant accident have confirmed that fallout radionuclides on the ground surface migrate through natural environment including soils and rivers. Therefore, in order to estimate future changes in radionuclide deposition, migration process of radionuclides in forests, soils, ground water, rivers should be monitored. However, such comprehensive studies on migration through forests, soils, ground water and rivers have not been conducted so far. Here, we present the following comprehensive investigation was conducted to confirm migration of radionuclides through natural environment including soils and rivers. 1)Study on depth distribution of radiocaesium in soils within forests, fields, and grassland 2)Confirmation of radionuclide distribution and investigation on migration in forests 3)Study on radionuclide migration due to soil erosion under different land use 4)Measurement of radionuclides entrained from natural environment including forests and soils 5)Investigation on radionuclide migration through soil water, ground water, stream water, spring water under different land use 6)Study on paddy-to-river transfer of radionuclides through suspended sediments 7)Study on river-to-ocean transfer of radionuclides via suspended sediments 8)Confirmation of radionuclide deposition in ponds and reservoirs

Utilization of natural hematite as reactive barrier for immobilization of radionuclides from radioactive liquid waste.

Science.gov (United States)

El Afifi, E M; Attallah, M F; Borai, E H

2016-01-01

Potential utilization of hematite as a natural material for immobilization of long-lived radionuclides from radioactive liquid waste was investigated. Hematite ore has been characterized by different analytical tools such as Fourier transformer infrared (FTIR), X-ray fluorescence (XRF), powder X-ray diffraction (XRD), thermogravimetry (TG) and differential thermal (DT) analysis, scanning electron microscopy (SEM) and BET-surface area. In this study, europium was used as REEs(III) and as a homolog of Am(III)-isotopes (such as (241)Am of 432.6 y, (242m)Am of 141 y and (243)Am of 7370 y). Micro particles of the hematite ore were used for treatment of radioactive waste containing (152+154)Eu(III). The results indicated that 96% (4.1 × 10(4) Bq) of (152+154)Eu(III) was efficiently retained onto hematite ore. Kinetic experiments indicated that the processes could be simulated by a pseudo-second-order model and suggested that the process may be chemisorption in nature. The applicability of Langmuir, Freundlich and Temkin models was investigated. It was found that Langmuir isotherm exhibited the best fit with the experimental results. It can be concluded that hematite is an economic and efficient reactive barrier for immobilization of long-lived radio isotopes of actinides and REEs(III). Copyright © 2015 Elsevier Ltd. All rights reserved.

Distribution of Europium between poly-maleic acid in solution or adsorbed onto alumina and Bacillus subtilis

International Nuclear Information System (INIS)

Markai, S.

2002-07-01

In order to understand the interactions of radionuclides under natural water conditions, the interactions were studied in a quaternary system composed of well characterized reference substances: europium as a heavy metal, poly-maleic acid (PMA) as model of humic substances, alumina as mineral phase and Bacillus subtilis representing biomass. The work was performed at pH=5 in 0,1 mol/L of NaClO 4 . The fundamental question addressed was to know if parameters deduced from the quantitative study of the reference systems Eu/PMA, Eu/PMA-Al 2 O 3 and Eu/Bacillus subtilis, could be used to quantify the distribution of Eu in the multi-substrate systems Eu/PMA/Bacillus subtilis and Eu/PMA-Al 2 O 3 /Bacillus subtilis. The experimental interaction data were described by a Langmuir-type model or by a surface complexation model, with surface speciation assessment by time resolved laser induced fluorescence spectroscopy. The study of the Eu/PMA system showed similarities with the Eu/ humic substances system as far as interaction strength and the nature of Eu environment were concerned. When PMA was adsorbed onto Al 2 O 3 , its complexation properties towards Eu were different. For high concentrations of Eu, a ternary complex was formed in which Eu was bound to a carboxylic function of PMA and to an aluminol function of Al 2 O 3 . For the Eu/B.subtilis system, Eu was bound to a carboxylic function and to a phosphate function. For the PMA/Eu/bacteria system, the reference systems were reversible and the parameters deduced from sub-systems allowed to quantify the distribution of Eu in the global system. In the PMA A l 2 O 3 /Eu/bacteria system, the equilibrium Eu/PMA-Al 2 O 3 was not reversible due to a diffusion of Eu in the adsorbed layer of PMA, reducing its bio-availability. (author)

Trace electrochemical analysis of Europium, Ytterbium, and Cerium at their joint presence in solution

Directory of Open Access Journals (Sweden)

Rema Matakova

2012-03-01

Full Text Available In the course of several decades at the department of analytical chemistry and chemistry of rare elements there were studied the electrode processes with participation of rare-earth metals (REM in accordance with the long awaiting problem of the development of rare-metal and rare-earth branch of non-ferrous metallurgy of Kazakhstan. With the aim of express and highly sensitive analytical control of raw materials and final product of rare-earth industry there were developed the methods of inversion-voltamperometric determination of low concentrations of europium, ytterbium and cerium under the conditions of their individual and combined presence in the solution.

Spectroscopic studies of an europium(III) tris-β-diketonate complex bearing a pyrazolylpyridine ligand

International Nuclear Information System (INIS)

Moreira dos Santos, Antonio; Coelho, Ana C.; Almeida Paz, Filipe A.; Rocha, Joao; Goncalves, Isabel S.; Carlos, Luis D.

2008-01-01

A new europium(III) complex, Eu(BTA) 3 (ethyl[3-(2-pyridyl)-1-pyrazolyl]acetate) (where BTA: 1-benzoyl-3,3,3-trifluoroacetonate), was synthesised by simple ligand exchange with the solvent adduct Eu(BTA) 3 (H 2 O) 2 . The compound was characterised by elemental analysis, thermogravimetry, FTIR, FT Raman and photoluminescence spectroscopies. A significant increase of the 5 D 0 lifetime of the complex, relative to the value found for the water-coordinated adduct (from 0.657 ± 0.001 to 0.835 ± 0.002 ms), and a larger contribution of the ligand levels to the excitation spectrum indicate a better photoluminescence performance for the former complex

On the contents of some radionuclides in precipitation (deposits) of Yerevan city, Armenia

International Nuclear Information System (INIS)

Ananyan, V.; Appleby, P.; Danagulyan, A.; Nalbandyan, A.

2004-01-01

Biosphere is exposed to cosmic and α -, β -, γ -radiation of numerous radionuclides dispersed in rocks, groundwater, terrestrial water of rivers, seas and oceans, air and biota. The main components of natural radiation are 40 K, 238 U, 232 Th and radioactive products of their decay. The goal of this investigation was to determine radionuclide composition of atmospheric precipitation (deposits) of Yerevan city. For sample collection we used sedimentation method, which covers all deposits on 1 m 2: admixtures, dust and sand fractions during wind (precipitation deposits). The dish made of neutral material (50 x 50 cm) was positioned at a height 1,5 m in a selected sampling site. The bottom of the dish was underlain by filtering paper. The samples were taken monthly. After deposit evaporation and ashing at 450 degree C the deposits were weighed. Total weight of such samples made 41 g for 2000 (12 months). For measurements one sample per season was selected (totally 4 samples). Radionuclide measurements were done on a low-background gamma-spectrometer with Hp Ge semiconductor detector. The exposures of sample measurement and background made 117,34 h each. The sample was positioned close to the detector. After removal of background, radionuclide concentrations were determined. Concentrations of all isotopes of uranium family (234 Th,214 Pb, 214 Bi), except 210 Pb in sample are similar (within the limits of error), so in natural environment they stay in equilibrium. The same is relevant also to radionuclides of thorium family. Concentrations of 210 Pb are almost threefold higher, this deserving further detailed research. Among the remaining isotopes, contents of 40 K are the highest as it greatly contributes to natural radioactive background (N RB). Concentrations of 137 Cs were minimal, as this radionuclide derives only from global man-made environmental pollution. Thus, the results have revealed the radionuclide composition of the sample of atmospheric deposits in

Conditions and processes affecting radionuclide transport

Science.gov (United States)

Simmons, Ardyth M.; Neymark, Leonid A.

2012-01-01

Characteristics of host rocks, secondary minerals, and fluids would affect the transport of radionuclides from a previously proposed repository at Yucca Mountain, Nevada. Minerals in the Yucca Mountain tuffs that are important for retarding radionuclides include clinoptilolite and mordenite (zeolites), clay minerals, and iron and manganese oxides and hydroxides. Water compositions along flow paths beneath Yucca Mountain are controlled by dissolution reactions, silica and calcite precipitation, and ion-exchange reactions. Radionuclide concentrations along flow paths from a repository could be limited by (1) low waste-form dissolution rates, (2) low radionuclide solubility, and (3) radionuclide sorption onto geological media.

Temperature dependence of the luminescence lifetime of a europium complex immobilized in different polymer matrices

Energy Technology Data Exchange (ETDEWEB)

Basu, Bharathi Bai J. [Surface Engineering Division, National Aerospace Laboratories, Bangalore 560017 (India)], E-mail: bharathi@css.nal.res.in; Vasantharajan, N. [Surface Engineering Division, National Aerospace Laboratories, Bangalore 560017 (India)

2008-10-15

The temperature dependence of the luminescence lifetime of temperature sensor films based on europium (III) thenoyltrifluoroacetonate (EuTTA) as sensor dye in various polymer matrices such as polystyrene (PS), polymethylmethacrylate (PMMA), polyurethane (PU) and model airplane dope was studied and compared. The luminescence lifetime of EuTTA was found to depend on the polymer matrix. The temperature sensitivity of lifetime was maximum for EuTTA-PS coating in the temperature range of 10-60 deg. C. The effect of concentration of the sensor dye in the polymer on the lifetime and temperature sensitivity was also studied.

A model for radionuclide Migration in Urban Environment and Drainage Systems

International Nuclear Information System (INIS)

Garcia, E.; Gallego, E.; Jimenez, F.

1998-01-01

The Model for Radionuclide Migration in Urban Environment and Drainage Systems aims to estimate the discharge of radioactivity removed by natural or forced decontamination into the receiving waters from the drainage system, as well as the radioactivity joined with the sludge produced in treatments plants, whose various applications can mean a potential hazard. This model, built in Powersim, is included in the MOIRA system, a project whose main aim is the evaluation of the situation after a radioactive contamination of the aquatic ecosystems and the estimation of optimal remedial strategies to restore the contaminated waters. Powersim is an easy-to-use software package which simulates dynamic processes. Two sub-models compose the global model: one, simulating the evolution of Cs-137 in urban areas, and the other, the behaviour of this radionuclide, once it ha entered the drainage systems, with the various existing alternatives of waste water treatment in Europe. (Author) 8 refs

Detection and evaluation of left atrial myxoma by gated radionuclide imaging

International Nuclear Information System (INIS)

Sugihara, Hiroki; Adachi, Haruhiko; Nakagawa, Hiroaki

1985-01-01

Radionuclide imaging plays an important role in diagnosising left atrial myxoma (LAM). We discussed diagnostic value of Fourier analysis with phase image and evaluated left ventricular filling function using indices such as 1/3 Filling Fraction, Rapid Filling Fraction and Peak Filling Rate derived from left ventricular volume curve. Equillibrium radionuclide angiocardiography was performed in 6 LAM patients. Phase delay in the basal portion of the left ventricle was shown in 5 of 6 LAM patients, and standard deviation of left ventricular phase was larger than these of controls. Left ventricular filling disturbance was suggested in 5 of 6 LAM patients. After surgical remove of myxoma phase delay was disappeared and standard deviation was normalized. And left ventricular filling was improved. We concluded that the phase image of Fourier analysis revealed a left atrial mass prolapsing in the left ventricule during the diastole, and that diastolic indices were useful for left ventricular filling disturbance due to LAM. (author)

Behavior and removal of organic species in the Savannah River Plant effluent treatment facility

International Nuclear Information System (INIS)

Oblath, S.B.; Georgeton, G.K.

1988-01-01

The effluent treatment facility (ETF) at the Savannah River Plant (SRP) is a new facility designed to treat and decontaminate low-level radioactive wastewater prior to release to the environment. The wastewater is primarily composed of evaporator overheads from the chemical separations and waste handling facilities at SRP. Primarily a 2000 mg/L NaNO 3 solution, the wastewater also contains microcurie-per-liter quantities of radionuclides and milligram-per-liter concentrations of heavy metals and organic components. This paper shows a block diagram of the major process steps. The pH adjustment, filtration, mercury removal, reverse osmosis, and cation-exchange polishing steps give a significant reduction of inorganic species and radionuclide (except trittium) concentrations. The activated carbon removal step was recently added to remove organic species to ensure that the effluent discharge permit limits for oil and grease and biochemical oxygen demand are met. The concentrates and regenerates from each of the treatment steps are further concentrated by evaporation to reduce the volume sufficiently for incorporation into and disposal as a grout

Magnesium ionophore II as an extraction agent for trivalent europium and americium

Energy Technology Data Exchange (ETDEWEB)

Makrlik, Emanuel [Czech Univ. of Life Sciences, Prague (Czech Republic). Faculty of Environmental Sciences; Vanura, Petr [Univ. of Chemistry and Technology, Prague (Czech Republic). Dept. of Analytical Chemistry

2016-11-01

Solvent extraction of microamounts of trivalent europium and americium into nitrobenzene by using a mixture of hydrogen dicarbollylcobaltate (H{sup +}B{sup -}) and magnesium ionophore II (L) was studied. The equilibrium data were explained assuming that the species HL{sup +}, HL{sup +}{sub 2}, ML{sup 3+}{sub 2}, and ML{sup 3+}{sub 3} (M{sup 3+} = Eu{sup 3+}, Am{sup 3+}; L=magnesium, ionophore II) are extracted into the nitrobenzene phase. Extraction and stability constants of the cationic complex species in nitrobenzene saturated with water were determined and discussed. From the experimental results it is evident that this effective magnesium ionophore II receptor for the Eu{sup 3+} and Am{sup 3+} cations could be considered as a potential extraction agent for nuclear waste treatment.

Calculation of the inventory and near-field release rates of radioactivity from neutron-activated metal parts discharged from the high flux isotope reactor and emplaced in solid waste storage area 6 at Oak Ridge National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Kelmers, A.D.; Hightower, J.R.

1987-05-01

Emplacement of contaminated reactor components involves disposal in lined and unlined auger holes in soil above the water table. The radionuclide inventory of disposed components was calculated. Information on the composition and weight of the components, as well as reasonable assumptions for the neutron flux fueling use, the time of neutron exposure, and radioactive decay after discharge, were employed in the inventory calculation. Near-field release rates of /sup 152/Eu, /sup 154/Eu, and /sup 155/Eu from control plates and cylinders were calculated for 50 years after emplacement. Release rates of the europium isotopes were uncertain. Two release-rate-limiting models were considered and a range of reasonable values were assumed for the time-to-failure of the auger-hole linear and aluminum cladding and europium solubility in SWSA-6 groundwater. The bounding europium radionuclide near-field release rates peaked at about 1.3 Ci/year total for /sup 152,154,155/Eu in 1987 for the lower bound, and at about 420 Ci/year in 1992 for the upper bound. The near-field release rates of /sup 55/Fe, /sup 59/Ni, /sup 60/Co, and /sup 63/Ni from stainless steel and cobalt alloy components, as well as of /sup 10/Be, /sup 41/Ca, and /sup 55/Fe from beryllium reflectors, were calculated for the next 100 years, assuming bulk waste corrosion was the release-rate-limiting step. Under the most conservative assumptions for the reflectors, the current (1986) total radionuclide release rate was calculated to be about 1.2 x 10/sup -4/ Ci/year, decreasing by 1992 to a steady release of about 1.5 x 10/sup -5/ Ci/year due primarily to /sup 41/Ca. 50 refs., 13 figs., 8 tabs.

Radionuclides in air, water, and biota

International Nuclear Information System (INIS)

Seymour, A.H.; Nelson, V.A.

1977-01-01

Air, water, and biological samples collected before and after the 1965, 1969, and 1971 underground nuclear detonations at Amchitka Island were analyzed for natural and fallout radionuclides by gamma spectrometry. Selected samples were also analyzed for tritium, 55 Fe, and 90 Sr. The objectives were to search for and identify radionuclides of Amchitka origin in the samples and to contribute to the general knowledge of the distribution of radionuclides in the environment. The studies showed that there has been no escape of radionuclides from the underground sites of the three nuclear detonations at Amchitka Island except for trace quantities of radionuclides, principally tritium, in water and soil gas samples from the immediate vicinity of the surface ground zero for the 1965 event. Two naturally occurring radionuclides, 40 K and 7 Be, were the most abundant radionuclides in the samples, usually by a factor of 10 or more, except for 137 Cs in lichen samples. All levels were well below applicable Radiation Protction Guides, often being near the statistical limit of detection

Synthesis and characterization of barium titanate, doped with europium and neodymium; Sintese e caracterizacao de titanato de bario, dopados com europio e neodimio

Energy Technology Data Exchange (ETDEWEB)

Sousa, Fernanda L.C.; Cabral, Alciney M.; Silva, Ademir O.; Oliveiro, Joao B.L., E-mail: nanda_louise@yahoo.com.br [Universidade Federal do Rio Grande do Norte (UFRN), Natal (Brazil). Instituto de Quimica

2013-07-01

This work aims at synthesize and characterize mixed oxides in Barium Titanium matrix in doping with Neodymium and Europium analyzing thermogravimetric curves, characteristic bands at infrared region of the polymer complex, which are intermediates to mixed oxides, and identify the formation thereof, and the crystallinity using XRD analysis.

Radionuclide migration test using undisturbed aerated soil

International Nuclear Information System (INIS)

Yamamoto, Tadatoshi; Ohtsuka, Yoshiro; Ogawa, Hiromichi; Wadachi, Yoshiki

1988-01-01

As one of the most important part of safety assessment on the shallow land disposal of lowlevel radioactive waste, the radionuclide migration was studied using undisturbed soil samples, in order to evaluate an exact radionuclide migration in an aerated soil layer. Soil samples used in the migration test were coastal sand and loamy soil which form typical surface soil layers in Japan. The aqueous solution containing 60 CoCl 2 , 85 SrCl 2 and 137 CsCl was fed into the soil column and concentration of each radionuclide both in effluent and in soil was measured. Large amount of radionuclides was adsorbed on the surface of soil column and small amount of radionuclides moved deep into the soil column. Difference in the radionuclide profile was observed in the low concentration portion particularly. It is that some fractions of 60 Co and 137 Cs are stable in non-ionic form and move downward through the soil column together with water. The radionuclide distribution in the surface of soil column can be fairly predicted with a conventional migration equation for ionic radionuclides. As a result of radionuclide adsorption, both aerated soil layers of coastal sand and loamy soil have large barrier ability on the radionuclide migration through the ground. (author)

Filters for water purification from oil products and radionuclides

International Nuclear Information System (INIS)

Khaydarov, R.R.; Khaydarov, R.A.; Gapurova, O.U.; Malikov, Sh.

2006-01-01

Full text: Purification of waste water and drinking water from radionuclides, heavy metal ions, and organic contaminants is one of the most important problems at present day. One of widely used methods for solving this problem is the ionic exchange method based on using different types of resins and fibroid sorbents. The paper deals with new chemically modified polyester fibroid filters having satisfactory adsorption characteristics. The process of the filter production includes their treatment by acrylo nitrilic emulsion for improving mechanical characteristics. An advantage of the fibroid ion-exchange sorbents over resin is in high rate of a sorption process, effective regeneration and small value of pressure drop of the sorbent layer for purified water. The specific surface of the fibroid sorbents is (2 - 3). 10'4 m 2 / kg, i.e. about 102 times greater than that of the resin (10 2 m 2 / kg). Owing to that fact the rate of the sorption process on the developed fibroid sorbents is much greater than that on the resin. The developed cation- and anion-exchange filters can be used for removing metal ions (Zn, Ni, Cu, Sb, Co, Cd, Cr, etc.) and organic compounds (M- P 32, M- I 131, M-Mo 99 mTc+99, etc.) from water. Capacity of the cation-exchange sorbents is 0.25 meq/g (Cu 2 +) and that of the anion - exchange is 0.45 meq/g (Cr 6 +). The cation- and anion-exchange filters are also selective for removing radionuclides Cs 134,137, Sr 90, Co 60 and I 129 in presence of Na + , K + , Ca 2 +, Mg 2 +, Cl - ions in water at concentrations up to 500 mg/L. New developed ionic-exchange sorbents have been used in drinking water filters and mini-systems for removing organic and inorganic contaminants, in the equipment for waste water purification from oil products (at atomic power stations, car-washing stations, etc), from heavy metal ions (in electronic industry, match fabrics, leather processing plants etc)

Radionuclides in food

International Nuclear Information System (INIS)

Fernandez Gomez, Isis Maria

2008-01-01

The sources of the presence of radionuclides in food are presented: natural radiation and artificial radiation. The transfer of radionuclides through food chains, intakes of radionuclides to the body with its partners effective doses and typical consumption of basic foods of a rural adult population are exposed as main topics. Also the radiation doses from natural sources and exposure to man by ingestion of contaminated food with radionuclides of artificial origin are shown. The contribution of the food ingestion to the man exposure depends on: characteristics of radionuclide, natural conditions, farming practices and eating habits of the population. The principal international organizations in charge of setting guide levels for radionuclides in food are mentioned: standards, rules and the monitoring. It establishes that a guide is necessary for the food monitoring; the alone CODEX ALIMENTARIUS is applicable to emergency situations and the generic action levels proposed by the CODEX not satisfy all needs (no guiding international levels for planned or existing situations such as NORM). There are handled mainly socio-economic and political aspects. Among the actions to be taken are: to assure a public comprehensive information over the risk evaluation in food; to reinforce the collaboration among the different international organizations (WHO, IAEA, ICRP, EC) in relation with the food of set; to give follow-up to the control of the drinkable water and NORM's presence in the food. In addition, it is possible to create the necessary mechanisms to reduce the number of irrelevant measures and bureaucratic useless steps (certificates); to promote the exchange between the different institutions involved in the topic of the food, with relation to the acquired experiences and learned lessons. Likewise, it might examine the possibility of a multidisciplinary approximation (radioactive and not radioactive pollutants); to elaborate a technical guide to assure the

Initial Radionuclide Inventories

Energy Technology Data Exchange (ETDEWEB)

H. Miller

2004-09-19

The purpose of this analysis is to provide an initial radionuclide inventory (in grams per waste package) and associated uncertainty distributions for use in the Total System Performance Assessment for the License Application (TSPA-LA) in support of the license application for the repository at Yucca Mountain, Nevada. This document is intended for use in postclosure analysis only. Bounding waste stream information and data were collected that capture probable limits. For commercially generated waste, this analysis considers alternative waste stream projections to bound the characteristics of wastes likely to be encountered using arrival scenarios that potentially impact the commercial spent nuclear fuel (CSNF) waste stream. For TSPA-LA, this radionuclide inventory analysis considers U.S. Department of Energy (DOE) high-level radioactive waste (DHLW) glass and two types of spent nuclear fuel (SNF): CSNF and DOE-owned (DSNF). These wastes are placed in two groups of waste packages: the CSNF waste package and the codisposal waste package (CDSP), which are designated to contain DHLW glass and DSNF, or DHLW glass only. The radionuclide inventory for naval SNF is provided separately in the classified ''Naval Nuclear Propulsion Program Technical Support Document'' for the License Application. As noted previously, the radionuclide inventory data presented here is intended only for TSPA-LA postclosure calculations. It is not applicable to preclosure safety calculations. Safe storage, transportation, and ultimate disposal of these wastes require safety analyses to support the design and licensing of repository equipment and facilities. These analyses will require radionuclide inventories to represent the radioactive source term that must be accommodated during handling, storage and disposition of these wastes. This analysis uses the best available information to identify the radionuclide inventory that is expected at the last year of last emplacement

Cesium removal flow studies using ion exchange

International Nuclear Information System (INIS)

Lee, D.D.; Walker, J.F. Jr.; Taylor, P.A.

1997-01-01

Cesium and strontium radionuclides are a small fraction of the mainly sodium and potassium salts in underground storage tank supernatant at US Department of Energy (DOE) sites at Hanford, Oak Ridge, Savannah River, and Idaho that DOE must remediate. Cesium-137 ( 137 Cs) is the primary gamma radiation source in the dissolved tank waste at these sites, and its removal from the supernatant can reduce the hazard and waste classification of the treated waste reducing the further treatment and disposal costs. Several cesium removal sorbents have been developed by private industry and the US DOE's Office of Science and Technology. Several of these removal technologies have been previously tested in small batch and column tests using simulated and a few actual supernatant under DOE's Environmental Management (EM) programs including the Tanks Focus Area (TFA) and the Efficient Separations and Processing (ESP) Cross-Cutting Program

Europium and samarium doped calcium sulfide thin films grown by PLD

International Nuclear Information System (INIS)

Christoulakis, S.; Suchea, M; Katsarakis, N.; Koudoumas, E

2007-01-01

Europium and samarium doped calcium sulfide thin films (CaS:Eu,Sm) with different thickness were prepared by the pulsed laser deposition technique using sintered targets. A typical homemade deposition chamber and XeCl excimer laser (308 nm) were employed and the films were deposited in helium atmosphere onto silicon and corning glass substrates. Structural investigations carried out by X-ray diffraction and atomic force microscopy showed a strong influence of the deposition parameters on the film properties. The films grown had an amorphous or polycrystalline structure depending on growth temperature and the number of pulses used, the same parameters affecting the film roughness, the grain shape and dimensions, the film thickness and the optical transmittance. This work indicates that pulsed laser deposition can be a suitable technique for the preparation of CaS:Eu,Sm thin films, the film characteristics being controlled by the growth conditions

Silver removal process development for the MEO cleanout

International Nuclear Information System (INIS)

Hsu, P.C.; Chiba, Z.; Schumacher, B.J.; Murguia, L.C.; Adamson, M.G.

1996-02-01

The Mediated Electrochemical Oxidation (MEO) system is an aqueous process which treats low-level mixed wastes by oxidizing the organic components of he waste into carbon dioxide and water. As MEO system continues to run, dissolved ash and radionuclides slowly accumulate in the anolyte and must be removed to maintain process efficiency. At such time, all of the anolyte is pumped into a still feed tank, and the silver ions need to be removed before sending the solution to a thin-film evaporator for further concentration. The efficiency of removing silver ions in the solution needs to be high enough such that the residual silver sent to Final Forms would be less than 1% wt. The purpose of this work is to develop an efficient process to remove silver ions during the MEO cleanout and to demonstrate the capability of centrifugation for separating small silver chloride particles from the solution. This development work includes lab scale experiments and bench scale tests. This report summarizes the results

Determination of alpha radionuclides in fish

International Nuclear Information System (INIS)

Pernicka, L.; Matel, L.; Rosskopfova, O.

2001-01-01

In atmospheric water, external water and undercurrent the occurrence of radionuclides is usual. It is an important factor of quality of the environment. Plants ingest radionuclides from water and with they everyone. And it arises radioactivity infest food-chain. Radiotoxicity of this radionuclides is very deer sometimes. The sensitive radiochemical procedures for their determination are necessarily important. The poster presents the combined procedure used at our laboratory for determination of alpha radionuclides in biological samples. (authors)

The determination of radionuclides and heavy metals in the phosphogypsum

International Nuclear Information System (INIS)

Rajkovic, M. B.; Markovic, M.; Vladisavljevic, G. T.; Stevanovic, R.

1999-01-01

Phosphogypsum is a waste product in phosphoric acid production using dihydrate wet phosphoric process. The radioactivity of the phosphogypsum is a consequence of the presence of radionuclides resulting from uranium radioactive decay. Presence of uranium in some phosphorites and its concentration depend on their source and variety whether they are primary or secondary can be 10-400 ppm. Radioactivity determined for phosphogypsum confirmed the presence of radionuclides U and 226 Ra. For this reason the methods of purification of raw phosphogypsum have been developed. An aqueous sulfuric acid solution having a concentration of 28 percent was admixed with a concentrated sulfuric acid solutions containing dissolved therein of barium sulfate at the temperature of 105 0 C, the slurry was cooled at a temperature of 30 0 C-35 0 C and then filtered. This purified phosphogypsum can be used independently, as a substitute for natural gypsum, or mixed with the natural gypsum. The consideration of the phosphogypsum is necessary because of the removal (or at least the reducing) of the enormous spoil areas of phosphogypsum and the diminution of the pollution. (author)

Radionuclide usage survey 1979-80

International Nuclear Information System (INIS)

Woods, M.J.

1980-08-01

Details of a survey by the Life Sciences Working Group of the International Committee for Radionuclide Metrology (ICRM) on radionuclide usage by medical physicists in 11 countries are presented. The results indicate that the radionuclide which will be of most significance in the future will be F-18, Fe-52, Ga-67, Ga-68, Kr-81m, Tc-99m, In-111, I-123, Xe-127 and Tl-201, (U.K.)

Chemiluminescence determination of tetracyclines using Fenton system in the presence europium(III) ions

International Nuclear Information System (INIS)

Kaczmarek, Malgorzata; Lis, Stefan

2009-01-01

A new simple chemiluminescent method for the determination of chlortetracycline (Chlor-TC), oxytetracycline (Oxy-TC) and doxycycline (Doxy-TC) is described. This method is based on the europium(III) emission as a result of the energy transfer process from the excited product of the tetracyclines oxidation to the uncomplexed Eu(III). Under the optimum conditions, calibration graphs were obtained for 4 x 10 -7 to 2 x 10 -5 mol L -1 of Chlor-TC; 2 x 10 -7 to 2 x 10 -5 mol L -1 of Oxy-TC and 1 x 10 -7 to 3 x 10 -5 mol L -1 of Doxy-TC. The method was successfully applied to the determination of these drugs in pharmaceutical and veterinary formulation and honey.

Sorption of Europium in zirconium silicate; Sorcion de Europio en silicato de circonio

Energy Technology Data Exchange (ETDEWEB)

Garcia R, G. [ININ, Carretera Mexico-Toluca Km. 36.5, 52045 Estado de Mexico (Mexico)

2004-07-01

Some minerals have the property of sipping radioactive metals in solution, that it takes advantage to manufacture contention barriers that are placed in the repositories of nuclear wastes. The more recent investigations are focused in the development of new technologies guided to the sorption of alpha emissors on minerals which avoid their dispersion in the environment. In an effort to contribute to the understanding of this type of properties, some studies of sorption of Europium III are presented like homologous of the americium, on the surface of zirconium silicate (ZrSiO{sub 4}). In this work the results of sorption experiences are presented as well as the interpretation of the phenomena of the formation of species in the surface of the zirconium silicate. (Author)

Removal of radionuclides from acid mine waters by retention on adsorbing materials

International Nuclear Information System (INIS)

Nascimento, M.R.L.; Fukuma, H.T.; Costa da, W.C.; Quinelato, A.L.; Gomes, H.A.; Garcia, O.Jr.

2006-01-01

This study proposes a method for decontamination of acid drainage water from a uranium mine, as an alternative process to lime treatment. The research embodied the recovery of uranium with an ion-exchange resin, treatment of effluent resin with lime, or with inorganic adsorbents and biosorbents. The uranium decontamination level using the resin process was 94% and allowed the recovery of this element as a commercial product. Among the inorganic adsorbents studied, phosphogypsum was effective for 226 Ra, 228 Ra, and 210 Pb removal. Among the biosorbents, Sargassum sp. was superior in relation to its specific capacity to accumulate and remove 226 Ra. (author)

Modified magnetic and optical properties of manganese nanoparticles incorporated europium doped magnesium borotellurite glass

Energy Technology Data Exchange (ETDEWEB)

Aziz, Siti Maisarah; Sahar, M.R., E-mail: mrahim057@gmail.com; Ghoshal, S.K.

2017-02-01

This paper reports the modified optical and magnetic properties of europium (Eu{sup 3+}) ions doped and Manganese nanoparticles (NPs) embedded Magnesium Borotellurite glass synthesized via melt quenching method. The influence of varying Mn NPs concentrations on the magnetic, absorption and emission properties of such glass samples are determined. Stables, transparent and amorphous glasses are obtained. The observed modification of the electronic polarizability is interpreted in terms of the generation of non-bridging oxygen (NBO) and bridging oxygen (BO) in the amorphous network. TEM images manifested the growth of Mn NPs with average diameter 11±1 nm. High-resolution TEM reveals that the lattice spacing of manganese nanoparticles is 0.308 nm at (112) plane. The emission spectra revealed four prominent peaks centered at 587 nm, 610 nm, 651 nm and 700 nm assigned to the transition from {sup 5}D{sub 0} →{sup 7}F{sub J} (J=1, 2, 3, 4) states of Eu{sup 3+} ion. A significant drop in the luminescence intensity due to the incorporation of Mn NPs is ascribed to the enhanced energy transfer from the Eu{sup 3+} ion to NPs. Prepared glass systems exhibited paramagnetic behavior. - Highlights: • The europium doped magnesium borotellurite glasses embedded Mn NPs prepared using the conventional melt-quenching method. • The TEM result reveals the size of Mn NPs while its planar spacing has been determined by HRTEM. • The luminescence properties of TeO{sub 2}–B{sub 2}O{sub 3}–MgO–Eu{sub 2}O{sub 3}–Mn{sub 3}O{sub 4} glasses have been investigated as effect of Mn NPs content. • The magnetization measurement of glass sample is carried out using vibrating sample magnetometer (VSM)

The use of some local plants for removal of radioactive and trace elements from aqueous media

International Nuclear Information System (INIS)

Al-Masri, M. S.; Amin, Y.; Al-Akel, B; Al-Naama, T.

2008-02-01

The removal of metal ions from aqueous solutions by biosorption plays an important role in water pollution control. In this study, dried leaves of Barbary, Jew's mallow and poplar, branches of poplar trees and creeping club as biomass for removal of toxic elements (Cd, Pb and U) and some radionuclides ( 133 Ba, 137 Cs and 226 Ra) from aqueous solution have been evaluated. The results show that all studied plants can be effectively used for removing U and Ba from aqueous solutions, while Pb was removed using branches of poplar trees. In addition, Cd was removed using Barbary, Jew's mallow and branches of poplar trees. The adsorption of U and Cd by leaves of Barbary reached 3.3 mg g -1 and 3.5 mg g -1 , respectively. Moreover, the leaves of poplar trees were the best plant for biosorping Pb, its maximum capacity reached a value 1.7 mg g -1 . On the other hand, the maximum capacity for studied radionuclide was less than 10-6 mg g -1 . Further more, the effect of many factors such as, plant pretreatment, solution temperature, pH, plant particles size and contact time, on biosorption process were performed and the best conditions of biosorption were recognized. The studied plants were used for removing 226 Ra and some trace elements from real polluted water. The results show that the method is effective.(author)

Radionuclide transport processes in terrestrial ecosystems

International Nuclear Information System (INIS)

Whicker, F.W.

1983-01-01

Some major principles and the status of knowledge concerning the transport of radionuclides through terrestrial ecosystems are reviewed. Fundamental processes which control the flow of radionuclides between ecosystem components such as air, soil, plants, and animals are described, with emphasis on deposition, resuspension, plant uptake, ingestion, and assimilation. Properties of radionuclides, organisms, and ecosystems are examined in relation to their influence on the accumulation of radioactive materials by plants and animals. The effects of the physicochemical nature of the radionuclide; morphology, physiology, and behavior of the organism; and soil, nutrient, and trophic characteristics of the ecosystem are highlighted. Observations in natural ecosystems on radionuclides such as 137 Cs, 90 Sr, 131 I, 3 H, and 239 Pu are used to illustrate current concepts. An assessment of the degree to which the processes controlling radionuclide behavior are understood and of our ability to simulate and predict such behavior with computerized models is offered. Finally, brief comments are made on research needs

Chemical states and electronic properties of the interface between aluminium and a photoluminescent conjugated copolymer containing europium complex

International Nuclear Information System (INIS)

Cai, Q.J.; Ling, Q.D.; Li, S.; Zhu, F.R.; Huang, Wei; Kang, E.T.; Neoh, K.G.

2004-01-01

The chemical states and electronic properties of the interface between thermally evaporated aluminium and a photoluminescent conjugated copolymer containing 9,9'-dihexylfluorene and europium complex-chelated benzoate units in the main chain (PF6-Eu(dbm) 2 phen) were studied in situ by X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). The changes in C 1s, Eu 3d, N 1s, and Al 2p core-level lineshapes with progressive deposition of aluminium atoms were carefully monitored. Aluminium was found to interact with the conjugated backbone of the copolymer to form the Al carbide, Al-O-C complex, and Al(III)-N chelate at the interface. In addition, the europium ions were reduced to the metallic state by the deposited aluminium atoms, which were oxidized and chelated by the 1,10-phenanthroline ligands (phen). The changes in chemical states at the interface suggest that the intramolecular energy transfer process in this copolymer had been affected. Moreover, aluminium also interacted with the bulk-adsorbed oxygen, which migrates to the surface in response to the deposition of aluminium atoms, to form a layer of metal oxides. On the other hand, the evolution of the UPS spectra suggests that the π-states of the conjugated system were affected and an unfavorable dipole layer was induced by the deposited aluminium atoms

Spectrochemical study of europium and neodymium complexes with 3-(3'-trifluoromethoxy-2',2',3',3'-tetrafluoropropionyl)camphor and bisheterocycles

International Nuclear Information System (INIS)

Khomenko, V.S.; Pavich, T.A.; Lozonskij, M.O.; Fialkov, Yu.A.; AN Ukrainskoj SSR, Kiev. Inst. Organicheskoj Khimii)

1987-01-01

Methods of mass-spectrometry, luminescent specroscopy and thermogravimetry are used to study decomposition ways, structure and volatility of mixed europium and neodymium complexes with fluorated organic ligands and bisheterocycles. It is shown that complexes containing an oxygen atom in a fluorated ligand elimination of difluorophosgene and tetrafluoroethylene molecules takes place. The addition of a bisheterocyclic ligand to a triligand complex makes the averaged bond in the complex more covalent and increase its volatility

Radionuclide Sensors for Water Monitoring

International Nuclear Information System (INIS)

Grate, Jay W.; Egorov, Oleg B.; DeVol, Timothy A.

2004-01-01

Radionuclide contamination in the soil and groundwater at U.S. Department of Energy (DOE) sites is a severe problem that requires monitoring and remediation. Radionuclide measurement techniques are needed to monitor surface waters, groundwater, and process waters. Typically, water samples are collected and transported to an analytical laboratory, where costly radiochemical analyses are performed. To date, there has been very little development of selective radionuclide sensors for alpha- and beta-emitting radionuclides such as 90Sr, 99Tc, and various actinides of interest. The objective of this project is to investigate novel sensor concepts and materials for sensitive and selective determination of beta- and alpha-emitting radionuclide contaminants in water. To meet the requirements for loW--level, isotope-specific detection, the proposed sensors are based on radiometric detection. As a means to address the fundamental challenge of the short ranges of beta and alpha particle s in water, our overall approach is based on localization of preconcentration/separation chemistries directly on or within the active area of a radioactivity detector. Automated microfluidics is used for sample manipulation and sensor regeneration or renewal. The outcome of these investigations will be the knowledge necessary to choose appropriate chemistries for selective preconcentration of radionuclides from environmental samples, new materials that combine chemical selectivity with scintillating properties, new materials that add chemical selectivity to solid-state diode detectors, new preconcentrating column sensors, and improved instrumentation and signal processing for selective radionuclide sensors. New knowledge will provide the basis for designing effective probes and instrumentation for field and in situ measurements

Radionuclides in terrestrial ecosystems

International Nuclear Information System (INIS)

Bocock, K.L.

1981-01-01

This report summarizes information on the distribution and movement of radionuclides in semi-natural terrestrial ecosystems in north-west England with particular emphasis on inputs to, and outputs from ecosystems; on plant and soil aspects; and on radionuclides in fallout and in discharges by the nuclear industry. (author)

Estimated environmental radionuclide transfer and deposition into outdoor swimming pools

International Nuclear Information System (INIS)

Tagami, Kazumi; Nagata, Izumi; Sueki, Keisuke

2014-01-01

In 2011, a large radioactive discharge occurred at the Fukushima Daiichi nuclear power plant. This plant is located within a climatically temperate region where outdoor swimming pools are popular. Although it is relatively easy to decontaminate pools by refilling them with fresh water, it is difficult to maintain safe conditions given highly contaminated diurnal dust falls from the surrounding contaminated ground. Our objectives in this paper were to conduct daily radioactivity measurements, to determine the quantity of radioactive contaminants from the surrounding environment that invade outdoor pools, and to investigate the efficacy of traditional pool cleaners in removing radioactive contaminants. The depositions in the paper filterable particulates ranged from 0 to 62,5 Bq/m 2 /day, with the highest levels found in the southern Tohoku District containing Fukushima Prefecture and in the Kanto District containing Tokyo Metro. They were approximately correlated with the ground contamination. Traditional pool cleaners eliminated 99% of contaminants at the bottom of the pool, reducing the concentration to 41 Bq/m 2 after cleaning. Authors recommended the deposition or the blown radionuclides into outdoor swimming pools must be considered into pool regulations when the environments exactly polluted with radionuclides. - Highlights: • Deposition into outdoor swimming pool in a habitable areas estimated 72 Bq/m 2 /day. • More than 500 Bq/m 2 /day deposition will exceed our national guideline (10 Bq/l) of swimming pool. • Vacuum pool cleaner eliminates 99% radionuclides deposition

Artificial radionuclides in soil, flora and fauna

International Nuclear Information System (INIS)

Marej, A.N.

1984-01-01

Sources and ways of soil contamination by radionuclides, as well as the main regularities of radionuclide behaviour in soils, are discussed. Ways of radionuclide uptake by plants are discussed in detail, since radionuclide contamination of vegetation, and agricultural plants and pastures in particular, is one of the main factors, determining sanitary value of environmental contamination by radioactive substances

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

Science.gov (United States)

Uba, Samuel

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

Mitochondria Targetable Time-Gated Luminescence Probe for Singlet Oxygen Based on a β-Diketonate-Europium Complex.

Science.gov (United States)

Sun, Jingyan; Song, Bo; Ye, Zhiqiang; Yuan, Jingli

2015-12-21

Singlet oxygen ((1)O2) plays a key role in the photodynamic therapy (PDT) technique of neoplastic diseases. In this work, by using a 9,10-dimethyl-2-anthryl-containing β-diketone, 1,1,1,2,2-pentafluoro-5-(9',10'-dimethyl-2'-anthryl)-3,5-pentanedione (Hpfdap), as a (1)O2-recognition ligand, a novel β-diketonate-europium(III) complex that can act as a luminescence probe for (1)O2, [Eu(pfdap)3(tpy)] (tpy = 2,2',2″-terpyridine), has been designed and synthesized for the time-gated luminescence detection of (1)O2 in living cells. The complex is weakly luminescent due to the quenching effect of 9,10-dimethyl-2-anthryl groups. After reaction with (1)O2, accompanied by the formation of endoperoxides of 9,10-dimethyl-2-anthryl groups, the luminescence quenching disappears, so that the long-lived luminescence of the europium(III) complex is switched on. The complex showed highly selective luminescence response to (1)O2 with a remarkable luminescence enhancement. Combined with the time-gated luminescence imaging technique, the complex was successfully used as a luminescent probe for the monitoring of the time-dependent generation of (1)O2 in 5-aminolevulinic acid (a PDT drug) loaded HepG2 cells during the photodynamic process. In addition, by coloading the complex and a mitochondrial indicator, Mito-Tracker Green, into HepG2 cells, the specific localization of [Eu(pfdap)3(tpy)] molecules in mitochondria of HepG2 cells was demonstrated by confocal fluorescence imaging measurements.

Environmental behaviour of radionuclides and transfer to man

International Nuclear Information System (INIS)

Smith, H.

1982-01-01

The environmental behaviour of the radionuclides making the major contribution to man's irradiation through diet is described. The following stages are emphasized: transfer of radionuclides to plants; transfer of radionuclides to animals; metabolism of inhaled or ingested radionuclides in animals providing food for man; transfer of radionuclides through the aquatic environment; application of food chain models. (43 references)

Nature of the concentration thresholds of europium atom yield from the oxidized tungsten surface under electron stimulated desorption

CERN Document Server

Davydov, S Y

2002-01-01

The nature of the electron-stimulated desorption (ESD) of the europium atoms by the E sub e irradiating electrons energies, equal to 50 and 80 eV, as well as peculiarities of the Eu atoms yield dependence on their concentration on the oxidized tungsten surface are discussed. It is shown, that the ESD originates by the electron transition from the interval 5p- or 5s shell of the tungsten surface atom onto the oxygen external unfilled 2p-level

First Test of a Radionuclide Trap at KNK II

International Nuclear Information System (INIS)

Stamm, H.-H.; Hanke, H.-D.; Clauss, H.

1984-03-01

The first test of an experimental radionuclide trap was performed at KNK II. The aim was to remove some Zn-65 and Mn-54 from the primary sodium. The 2.3 l trap was filled with stainless steel and nickel pallrings of different sizes and was operated for 100 hours at 312 ''0C and a flow rate of 1.6 m''3 Na/h. On the Ni samples 110 times the amount of Mn-54 and 440 times the amount of Zn-65 have been sorbed compared to stainless steel pallrings of the same size. The activity sorbed was proportional to the surface area

Preparation and fluorescent recognition properties for fluoride of a nanostructured covalently bonded europium hybrid material

Institute of Scientific and Technical Information of China (English)

余旭东; 李景印; 李亚娟; 耿丽君; 甄小丽; 于涛

2015-01-01

A novel covalently bonded Eu3+-based silica hybrid material was designed and its spectrophotometric anion sensing prop-erty was studied. The fluorescent receptor (europium complex) was covalently grafted to the silica matrix via a sol-gel approach. FTIR, UV-vis spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and photoluminescent spectra were characterized, and the results revealed that the hybrid material with nanosphere structure displayed excellent photophysical property. In addition, the selective anion sensing property of the hybrid material was studied by UV-vis and fluorescence spectra. The results showed that the hybrid material exhibited a smart response with fluoride anions.

Radioactivity: radionuclides in foods

International Nuclear Information System (INIS)

Simpson, R.E.; Baratta, E.J.; Jelinek, C.F.

1977-01-01

The results are summarized of the analysis for strontium-90, cesium-137, iodine-131, ruthenium-106, and potassium-40, a naturally occurring radionuclide, in samples of total diet and selected import commodities in the foods compliance program of the Food and Drug Administration. On the basis of the radionuclide intake guidelines established by the Federal Radiation Council (FRC), the low content of radionuclides found in the total diet samples for fiscal years 1973 and 1974 demonstrates the need for surveillance only at the present level. The low levels of radionuclides found in a limited number of edible imported commodities indicate that their contribution to the total diet would not increase the levels of these radionuclides above those recommended for only periodic surveillance by the FRC. The potassium levels, determined from potassium-40 activity, found in meats and fish agree with the value for normal muscle tissue for the reference man reported by the International Commission on Radiation Protection. Of the other commodities, nuts contained the highest levels, while sugar, beverages, and processed foods contained the lowest levels of potassium. Although cesium and potassium are chemical analogs with similar metabolic properties, because of their variable content in some leafy samples as a result of surface contamination, a correlation between cesium-137 levels and the cesium-137-to-potassium ratio was inconclusive

Inverse problem in radionuclide transport

International Nuclear Information System (INIS)

Yu, C.

1988-01-01

The disposal of radioactive waste must comply with the performance objectives set forth in 10 CFR 61 for low-level waste (LLW) and 10 CFR 60 for high-level waste (HLW). To determine probable compliance, the proposed disposal system can be modeled to predict its performance. One of the difficulties encountered in such a study is modeling the migration of radionuclides through a complex geologic medium for the long term. Although many radionuclide transport models exist in the literature, the accuracy of the model prediction is highly dependent on the model parameters used. The problem of using known parameters in a radionuclide transport model to predict radionuclide concentrations is a direct problem (DP); whereas the reverse of DP, i.e., the parameter identification problem of determining model parameters from known radionuclide concentrations, is called the inverse problem (IP). In this study, a procedure to solve IP is tested, using the regression technique. Several nonlinear regression programs are examined, and the best one is recommended. 13 refs., 1 tab

Radionuclide Retention in Concrete Wasteforms

Energy Technology Data Exchange (ETDEWEB)

Wellman, Dawn M.; Jansik, Danielle P.; Golovich, Elizabeth C.; Cordova, Elsa A.

2012-09-24

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of LLW and MLLW, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.

Sediment and radionuclide transport in rivers: radionuclide transport modeling for Cattaraugus and Buttermilk Creeks, New York

International Nuclear Information System (INIS)

Onishi, Y.; Yabusaki, S.B.; Kincaid, C.T.; Skaggs, R.L.; Walters, W.H.

1982-12-01

SERATRA, a transient, two-dimensional (laterally-averaged) computer model of sediment-contaminant transport in rivers, satisfactorily resolved the distribution of sediment and radionuclide concentrations in the Cattaraugus Creek stream system in New York. By modeling the physical processes of advection, diffusion, erosion, deposition, and bed armoring, SERATRA routed three sediment size fractions, including cohesive soils, to simulate three dynamic flow events. In conjunction with the sediment transport, SERATRA computed radionuclide levels in dissolved, suspended sediment, and bed sediment forms for four radionuclides ( 137 Cs, 90 Sr, 239 240 Pu, and 3 H). By accounting for time-dependent sediment-radionuclide interaction in the water column and bed, SERATA is a physically explicit model of radionuclide fate and migration. Sediment and radionuclide concentrations calculated by SERATA in the Cattaraugus Creek stream system are in reasonable agreement with measured values. SERATRA is in the field performance phase of an extensive testing program designed to establish the utility of the model as a site assessment tool. The model handles not only radionuclides but other contaminants such as pesticides, heavy metals and other toxic chemicals. Now that the model has been applied to four field sites, including the latest study of the Cattaraugus Creek stream system, it is recommended that a final model be validated through comparison of predicted results with field data from a carefully controlled tracer test at a field site. It is also recommended that a detailed laboratory flume be tested to study cohesive sediment transport, deposition, and erosion characteristics. The lack of current understanding of these characteristics is one of the weakest areas hindering the accurate assessment of the migration of radionuclides sorbed by fine sediments of silt and clay

RBS and RNRA studies on sorption of europium by apatite

Energy Technology Data Exchange (ETDEWEB)

Ohnuki, Toshihiko; Kozai, Naofumi; Isobe, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Murakami, Takashi; Yamamoto, Shunya; Aoki, Yasushi; Naramoto, Hiroshi

1997-03-01

The sorption mechanism of europium, alternative of trivalent TRU has been studied based on the depth profiles of elements obtained by Rutherford Backscattering Spectroscopy (RBS) and Resonant Nuclear Reaction Analysis (RNRA). The positive peak for Eu and the negative peak for Ca were observed in the subtracted RBS spectra of the apatites on which Eu was sorbed from that of the fresh apatite. This indicates that Eu was sorbed on apatite, while a fraction of Ca was released from apatite. The peak height for Eu in the RBS spectrum of the apatite obtained at 75degC was higher than that of the apatite at 40degC. The depth profile of hydrogen of the apatite on which Eu was sorbed was similar to that of the fresh apatite. The concentration of Eu in the solution decreased with increasing temperature. On the contrary, the concentration of Ca increased with increasing temperature. Thus, it is concluded that a fraction of Eu is exchanged for Ca in the structure of apatite. (author)

Synthesis, Structure, and Luminescent Properties of Europium-Doped Hydroxyapatite Nanocrystalline Powders

Directory of Open Access Journals (Sweden)

Carmen Steluta Ciobanu

2012-01-01

Full Text Available The luminescent europium-doped hydroxyapatite (Eu:HAp, Ca10−xEux(PO46(OH2 with 0≤x≤0.2 nanocrystalline powders was synthesized by coprecipitation. The structural, morphological, and textural properties were well characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The vibrational studies were performed by Fourier transform infrared, Raman, and photoluminescence spectroscopies. The X-ray diffraction analysis revealed that hydroxyapatite is the unique crystalline constituent of all the samples, indicating that Eu has been successfully inserted into the HAp lattice. Eu doping inhibits HAp crystallization, leading to a decrease of the average crystallite size from around 20 nm in the undoped sample to around 7 nm in the sample with the highest Eu concentration. Furthermore, the samples show the characteristic 5D0→7F0 transition observed at 578 nm related to Eu3+ ions distributed on Ca2+ sites of the apatitic structure.

Synthesis, Structure, and Luminescent Properties of Europium-Doped Hydroxyapatite Nanocrystalline Powders

International Nuclear Information System (INIS)

Ciobanu, C.S.; Iconaru, S.L.; Predoi, D.; Massuyeau, F.; Constantin, L.V.; Costescu, A.

2012-01-01

The luminescent europium-doped hydroxyapatite (Eu:HAp, Ca 10-x Eu x (PO 4 ) 6 (OH) 2 ) with 0>x>0.2 nanocrystalline powders was synthesized by coprecipitation. The structural, morphological, and textural properties were well characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The vibrational studies were performed by Fourier transform infrared, Raman, and photoluminescence spectroscopies. The X-ray diffraction analysis revealed that hydroxyapatite is the unique crystalline constituent of all the samples, indicating that Eu has been successfully inserted into the HAp lattice. Eu doping inhibits HAp crystallization, leading to a decrease of the average crystallite size from around 20 nm in the undoped sample to around 7 nm in the sample with the highest Eu concentration. Furthermore, the samples show the characteristic 5 D 0 → 7 F 0 transition observed at 578 nm related to Eu 3+ ions distributed on Ca 2+ sites of the apatitic structure

Modeling Radionuclide Decay Chain Migration Using HYDROGEOCHEM

Science.gov (United States)

Lin, T. C.; Tsai, C. H.; Lai, K. H.; Chen, J. S.

2014-12-01

Nuclear technology has been employed for energy production for several decades. Although people receive many benefits from nuclear energy, there are inevitably environmental pollutions as well as human health threats posed by the radioactive materials releases from nuclear waste disposed in geological repositories or accidental releases of radionuclides from nuclear facilities. Theoretical studies have been undertaken to understand the transport of radionuclides in subsurface environments because that the radionuclide transport in groundwater is one of the main pathway in exposure scenarios for the intake of radionuclides. The radionuclide transport in groundwater can be predicted using analytical solution as well as numerical models. In this study, we simulate the transport of the radionuclide decay chain using HYDROGEOCHEM. The simulated results are verified against the analytical solution available in the literature. Excellent agreements between the numerical simulation and the analytical are observed for a wide spectrum of concentration. HYDROGECHEM is a useful tool assessing the ecological and environmental impact of the accidental radionuclide releases such as the Fukushima nuclear disaster where multiple radionuclides leaked through the reactor, subsequently contaminating the local groundwater and ocean seawater in the vicinity of the nuclear plant.

Fluorescence properties of europium and samarium. beta. -diketonates and their use in fluorometry

Energy Technology Data Exchange (ETDEWEB)

Huang, H; Hiraki, K; Nishikawa, Y [Kinki Univ., Higashi-Osaka, Osaka (Japan). Faculty of Science and Technology

1981-01-01

Several europium and samarium ..beta..-diketonates (tta, ntfa, bfa) complexed with 1, 10-phenanthroline, or with trioctylphosphine oxide (topo) were synthesized. The fluorescence properties of these compounds in benzene or hexane have been studied. Absorption and fluorescence spectra, fluorescence quantum yield, fluorescence sensitivity index (F.S.I.), and fluorescence lifetime were measured. From the measurement of fluorescence lifetime of the ..beta..-diketonates, the velocity of radiative process (k sub(f)/phi sub(f)) has almost the same value for benzene and hexane solvent. The red fluorescence (Em. max. : 619 nm) of Eu(III) in these chelates is attributed to transitions from /sup 5/D/sub 0/ ..-->.. /sup 7/F/sub 2/ levels of this ion, and the three-band spectrum (Em. max. : 569 nm, 606 nm, 650 nm) indicates the transitions from the /sup 4/G sub(5/2) ..-->.. /sup 6/H sub(5/2), /sup 4/G sub(5/2) ..-->.. /sup 6/H sub(7/2), and /sup 4/G sub(5/2) ..-->.. /sup 6/H sub(9/2) levels of Sm(III), respectively. These spectra are not changed by any solvents and ligands. From the results, the fluorescence of the ..beta..-diketonates in organic solvent has been attributed to m* ..-->.. m luminescence transition. The complexes of Eu(III) and Sm(III) show radiative transition within orbitals, composed exclusively of 4f orbitals of rare earth ions (m* ..-->.. m radiative transition). Fluorinated ligands show better sensitivity than unfluorinated ligands, and the best sensitivity is obtained with TTA-phen system, and/or TTA-topo system for the spectrofluorometric determination of the two metals. In the case of Eu determination, 619 nm emission wavelength is used (the determinable range : 0.2 -- 10 ppb Eu), and in the case of Sm determination, 650 nm emission wavelength is adopted (the determinable range : 0.1 -- 1 ppm Sm), because of much higher sensitivity than the other two peaks (569, 606 nm) without interference from europium complex.

Application of crown-ethers to cesium and strontium removal from Marcoule reprocessing concentrate

International Nuclear Information System (INIS)

Dozol, J.F.; Casas I Garcia, J.

1990-01-01

The liquid wastes arising from reprocessing plants are treated by evaporation, the distillate is discharged into environment and the concentrate containing all the active and inactive salts must be stored in geological formation, after embedding, due to the activity of long life radionuclides (actinides, Cs, Sr). The objective of this work, is after removal actinides, to remove cesium/strontium from high sodium content acidic concentrates in order to sharply decrease the volume of wastes to be stored in geological formation

Measurement of radionuclides in waste packages

Science.gov (United States)

Brodzinski, R.L.; Perkins, R.W.; Rieck, H.G.; Wogman, N.A.

1984-09-12

A method is described for non-destructively assaying the radionuclide content of solid waste in a sealed container by analysis of the waste's gamma-ray spectrum and neutron emissions. Some radionuclides are measured by characteristic photopeaks in the gamma-ray spectrum; transuranic nuclides are measured by neutron emission rate; other radionuclides are measured by correlation with those already measured.

Testing and modelling the performance of inorganic exchangers for radionuclide removal from aqueous nuclear waste

International Nuclear Information System (INIS)

Harjula, R.; Lehto, J.; Paajanen, A.; Saarinen, L.

1997-01-01

Three different inorganic sorbents/ion exchangers have been tested in this work. Granular hexacyanoferrate-based ion exchanger was developed for Cs removal from radioactive liquid waste at NPPs. It was tested for Cs removal from waste solutions containing different complexing agents and detergents. Radiation stability and thermal stability test has shown, that this sorbent can be used for treatment of medium-active waste treatment. Active carbon materials were tested for Co removal from liquid waste effluents at NPPs. It was found that 60 Co cannot be removed from the evaporator concentrates with reasonable efficiency and a combined process with up-stream precipitation step is needed for better Co separation efficiency. Granular modified titanium oxide was tested for 90 Sr removal from the waste effluents and showed very high efficiency. A mathematical model was developed to analyze ion exchange performance in feeds of different chemical and radiochemical compositions. (author). 9 refs, 7 figs, 3 tabs

Chemiluminescence determination of tetracyclines using Fenton system in the presence europium(III) ions

Energy Technology Data Exchange (ETDEWEB)

Kaczmarek, Malgorzata [Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60 - 780 Poznan (Poland); Lis, Stefan [Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60 - 780 Poznan (Poland)

2009-04-20

A new simple chemiluminescent method for the determination of chlortetracycline (Chlor-TC), oxytetracycline (Oxy-TC) and doxycycline (Doxy-TC) is described. This method is based on the europium(III) emission as a result of the energy transfer process from the excited product of the tetracyclines oxidation to the uncomplexed Eu(III). Under the optimum conditions, calibration graphs were obtained for 4 x 10{sup -7} to 2 x 10{sup -5} mol L{sup -1} of Chlor-TC; 2 x 10{sup -7} to 2 x 10{sup -5} mol L{sup -1} of Oxy-TC and 1 x 10{sup -7} to 3 x 10{sup -5} mol L{sup -1} of Doxy-TC. The method was successfully applied to the determination of these drugs in pharmaceutical and veterinary formulation and honey.

Speciation of radionuclides in the environment

International Nuclear Information System (INIS)

Gunten, H.R. von; Benes, P.

1994-02-01

Methods for the determination of the speciation of radionuclides in aerosols, in aquatic solutions, in sediments, soils and rocks are reviewed. At present, most of the results about speciation are deduced from model calculations, model experiments, and separation of species (forms) of radionuclides, e.g., by sequential extraction procedures. Methods of direct determination of speciation of radionuclides (e.g. by laser induced spectroscopy) are in general not yet sensitive enough for a measurement of the very low concentrations of radionuclides in the environment. The methodological part of this paper is followed by a review of the very abundant literature about speciation of important radionuclides in the environment, i.e. in the atmosphere, hydrosphere and lithosphere. The review does not include the biosphere. Literature up to spring 1993 is included (with a few more recent additions). (author)

Radionuclide transport in a single fissure

International Nuclear Information System (INIS)

Eriksen, T.E.

1983-01-01

Radionuclide migration have been studied in natural fissures orieted parallel to the axis of granite drill cores. A short pulse of the radionuclides solution was injected at one end of the fissure and the temporal change in radionuclide concentration of the eluate measured. After several hundred fissure volumes water had been pumped through the fissure following the radionuclide pulse the activity distribution on the fissure surfaces was measured. From the retardation of 152 Eu, 235 Np and 237 Pu it is concluded that these radionuclides are transported in the oxidation states Eu(III), Pu(IV) and Np(V). The distribution coefficients K sub (d) calculated from flow and activity distribution data on the basis of geometric surface area/volume ratios are of the same order as published K sub (d) values obtained from batch equilibrium experiments. (Author)

Stability constants of the Europium complexes with the chloride ions; Constantes de estabilidad de los complejos del europio con los iones cloruro

Energy Technology Data Exchange (ETDEWEB)

Jimenez R, M.; Solache R, M.; Rojas H, A. [Instituto Nacional de Investigaciones Nucleares, Departamento de Quimica, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

2000-07-01

The stability constants of lanthanides complexes with chloride ions which were determined at the same ionic force but in different media, are significantly different. It does not exist a systematic study over these stability constants. The purpose of this work is to determine the stability constants of the europium complexes with chloride ions at 303 K, by the solvents extraction method. (Author)

Measurement of anthropogenic radionuclides in the atmosphere with a radionuclide monitoring network for nuclear tests

International Nuclear Information System (INIS)

Yonezawa, Chushiro; Yamamoto, Yoichi

2011-01-01

A worldwide radionuclide monitoring network for nuclear tests has detected the anthropogenic radioactive materials released in the atmosphere due to the accident of the Fukushima Daiichi Nuclear Power Plant impacted by the Great East Japan Earthquake on March 11, 2011. After four months have passed since the accident occurred, most overseas stations do not detect the radionuclides of Fukushima origin any more. The Takasaki station in Japan, however, is still detecting them every day. This paper describes radionuclide monitoring stations and the network of them as part of the International Monitoring System (IMS) in the Comprehensive Nuclear Test Ban Treaty (CTBT), as well as the measurement results of radionuclide particulates and radioactive isotopes of xenon released from the Fukushima Daiichi Nuclear Power Plant with the monitoring network. (J.P.N.)

Radionuclide behavior in water saturated porous media: Diffusion and infiltration coupling of thermodynamically and kinetically controlled radionuclide water - mineral interactions

International Nuclear Information System (INIS)

Spasennykh, M.Yu.; Apps, J.A.

1995-05-01

A model is developed describing one dimensional radionuclide transport in porous media coupled with locally reversible radionuclide water-mineral exchange reactions and radioactive decay. Problems are considered in which radionuclide transport by diffusion and infiltration processes occur in cases where radionuclide water-solid interaction are kinetically and thermodynamically controlled. The limits of Sr-90 and Cs-137 migration are calculated over a wide range of the problem variables (infiltration velocity, distribution coefficients, and rate constants of water-mineral radionuclide exchange reactions)

A vector Wiener filter for dual-radionuclide imaging

International Nuclear Information System (INIS)

Links, J.M.; Prince, J.L.; Gupta, S.N.

1996-01-01

The routine use of a single radionuclide for patient imaging in nuclear medicine can be complemented by studies employing two tracers to examine two different processes in a single organ, most frequently by simultaneous imaging of both radionuclides in two different energy windows. In addition, simultaneous transmission/emission imaging with dual-radionuclides has been described, with one radionuclide used for the transmission study and a second for the emission study. There is thus currently considerable interest in dual-radionuclide imaging. A major problem with all dual-radionuclide imaging is the crosstalk between the two radionuclides. Such crosstalk frequently occurs, because scattered radiation from the higher energy radionuclide is detected in the lower energy window, and because the lower energy radionuclide may have higher energy emissions which are detected in the higher energy window. The authors have previously described the use of Fourier-based restoration filtering in single photon emission computed tomography (SPECT) and positron emission tomography (PET) to improve quantitative accuracy by designing a Wiener or other Fourier filter to partially restore the loss of contrast due to scatter and finite spatial resolution effects. The authors describe here the derivation and initial validation of an extension of such filtering for dual-radionuclide imaging that simultaneously (1) improves contrast in each radionuclide's direct image, (2) reduces image noise, and (3) reduces the crosstalk contribution from the other radionuclide. This filter is based on a vector version of the Wiener filter, which is shown to be superior [in the minimum mean square error (MMSE) sense] to the sequential application of separate crosstalk and restoration filters

Hot demonstration of proposed commercial nuclide removal technology

International Nuclear Information System (INIS)

Lee, D.

1996-01-01

This task covers the development and operation of an experimental test unit located in a Building 4501 hot cell within Building 4501 at Oak Ridge National Laboratory (ORNL). This equipment is designed to test radionuclides removal technologies under continuous operatoin on actual ORNL Melton Valley Storage Tank (MVST) supernatant, Savannah River high-level waste supernatant, and Hanford supernatant. The latter two may be simulated by adding the appropriate chemicals and/or nuclides to the MVST supernatant

Natural Radionuclides and Isotopic Signatures for Determining Carbonaceous Aerosol Sources, Aerosol Lifetimes, and Washout Processes

International Nuclear Information System (INIS)

Gaffney, Jeffrey

2012-01-01

This is the final technical report. The project description is as follows: to determine the role of aerosol radiative forcing on climate, the processes that control their atmospheric concentrations must be understood, and aerosol sources need to be determined for mitigation. Measurements of naturally occurring radionuclides and stable isotopic signatures allow the sources, removal and transport processes, as well as atmospheric lifetimes of fine carbonaceous aerosols, to be evaluated.

Natural Radionuclides and Isotopic Signatures for Determining Carbonaceous Aerosol Sources, Aerosol Lifetimes, and Washout Processes

Energy Technology Data Exchange (ETDEWEB)

Gaffney, Jeffrey [Univ. of Arkansas, Little Rock, AR (United States)

2012-12-12

This is the final technical report. The project description is as follows: to determine the role of aerosol radiative forcing on climate, the processes that control their atmospheric concentrations must be understood, and aerosol sources need to be determined for mitigation. Measurements of naturally occurring radionuclides and stable isotopic signatures allow the sources, removal and transport processes, as well as atmospheric lifetimes of fine carbonaceous aerosols, to be evaluated.

Preparation and characterization of porous reduced graphene oxide based inverse spinel nickel ferrite nanocomposite for adsorption removal of radionuclides

Energy Technology Data Exchange (ETDEWEB)

Lingamdinne, Lakshmi Prasanna; Choi, Yu-Lim [Department of Environmental Engineering, Kwangwoon University, Seoul, 139-701 (Korea, Republic of); Kim, Im-Soon [Graduate School of Environmental Studies, Kwangwoon University, Seoul, 139-701 (Korea, Republic of); Yang, Jae-Kyu [Ingenium College of Liberal Arts, Kwangwoon University, Seoul, 139-701 (Korea, Republic of); Koduru, Janardhan Reddy, E-mail: reddyjchem@gmail.com [Graduate School of Environmental Studies, Kwangwoon University, Seoul, 139-701 (Korea, Republic of); Chang, Yoon-Young, E-mail: yychang@kw.ac.kr [Department of Environmental Engineering, Kwangwoon University, Seoul, 139-701 (Korea, Republic of)

2017-03-15

Highlights: • Novel porous Ferromagnetic, GONF and Superparamagnetic, rGONF preparation. • The nanosize particles GONF (41.14 nm) and rGONF (32.16 nm) preparation. • Adsorption mechanism and modeling developments for radionuclides. • Zeta potential and surface site density of nanocomposites for comparison. - Abstract: For the removal of uranium(VI) (U(VI)) and thorium(IV) (Th(IV)), graphene oxide based inverse spinel nickel ferrite (GONF) nanocomposite and reduced graphene oxide based inverse spinel nickel ferrite (rGONF) nanocomposite were prepared by co-precipitation of GO with nickel and iron salts in one pot. The spectral characterization analyses revealed that GONF and rGONF have a porous surface morphology with an average particle size of 41.41 nm and 32.16 nm, respectively. The magnetic property measurement system (MPMS) studies confirmed the formation of ferromagnetic GONF and superparamagnetic rGONF. The adsorption kinetics studies found that the pseudo-second-order kinetics was well tune to the U(VI) and Th(IV) adsorption. The results of adsorption isotherms showed that the adsorption of U(VI) and Th(IV) were due to the monolayer on homogeneous surface of the GONF and rGONF. The adsorptions of both U(VI) and Th(IV) were increased with increasing system temperature from 293 to 333 ± 2 K. The thermodynamic studies reveal that the U(VI) and Th(IV) adsorption onto GONF and rGONF was endothermic. GONF and rGONF, which could be separated by external magnetic field, were recycled and re-used for up to five cycles without any significant loss of adsorption capacity.

Radionuclides in Canada goose eggs

International Nuclear Information System (INIS)

Rickard, W.H.; Sweany, H.A.

1975-01-01

Low levels of radionuclides were measured in Canada goose eggs taken from deserted nests from Columbia River islands on the Energy Research and Development Administration's Hanford Reservation. Potassium-40, a naturally occurring radionuclide, was the most abundant radionuclide measured in egg contents and egg shell. Strontium-90 was incorporated into egg shells and cesium-137 into inner egg contents. Manganese-54, cobalt-60, and zinc-65 were more abundant in inner egg contents than in egg shell. Cerium-144 was detected in egg shell but not in inner shell

Sensors and Automated Analyzers for Radionuclides

International Nuclear Information System (INIS)

Grate, Jay W.; Egorov, Oleg B.

2003-01-01

The production of nuclear weapons materials has generated large quantities of nuclear waste and significant environmental contamination. We have developed new, rapid, automated methods for determination of radionuclides using sequential injection methodologies to automate extraction chromatographic separations, with on-line flow-through scintillation counting for real time detection. This work has progressed in two main areas: radionuclide sensors for water monitoring and automated radiochemical analyzers for monitoring nuclear waste processing operations. Radionuclide sensors have been developed that collect and concentrate radionuclides in preconcentrating minicolumns with dual functionality: chemical selectivity for radionuclide capture and scintillation for signal output. These sensors can detect pertechnetate to below regulatory levels and have been engineered into a prototype for field testing. A fully automated process monitor has been developed for total technetium in nuclear waste streams. This instrument performs sample acidification, speciation adjustment, separation and detection in fifteen minutes or less

Radionuclide deposition control

International Nuclear Information System (INIS)

1980-01-01

A method is described for controlling the deposition, on to the surfaces of reactor components, of the radionuclides manganese-54, cobalt-58 and cobalt-60 from a liquid stream containing the radionuclides. The method consists of disposing a getter material (nickel) in the liquid stream, and a non-getter material (tantalum, tungsten or molybdenum) as a coating on the surfaces where deposition is not desired. The process is described with special reference to its use in the coolant circuit in sodium cooled fast breeder reactors. (U.K.)

Association of actinides with microorganisms and clay: Implications for radionuclide migration from waste-repository sites

International Nuclear Information System (INIS)

Ohnuki, T.; Francis, A.; Kozai, N.; Sakamoto, F.; Ozaki, T.; Nankawa, T.; Suzuki, Y.

2010-01-01

We conducted a series of basic studies on the microbial accumulation of actinides to elucidate their migration behavior around backfill materials used in the geological disposal of radioactive wastes. We explored the interactions of U(VI) and Pu(VI) with Bacillus subtilis, kaolinite clay, and within a mixture of the two, directly analyzing their association with the bacterium in the mixture by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The accumulation of U by the mixture rose as the numbers of B. subtilis cells increased. Treating the kaolinite with potassium acetate (CH 3 COOK) removed approximately 80% of the associated uranium while only 65% was removed in the presence of B. subtilis. TEM-EDS analysis confirmed that most of the U taken from solution was associated with B. subtilis. XANES analyses revealed that the oxidation state of uranium associated with B. subtilis, kaolinite, and with the mixture containing both was U(VI). The amount of Pu sorbed by B. subtilis increased with time, but did not reach equilibrium in 48 h; in kaolinite alone, equilibrium was attained within 8 h. After 48 h, the oxidation state of Pu in the solutions exposed to B. subtilis and to the mixture had changed to Pu(V), whereas the oxidation state of the Pu associated with both was Pu(IV). In contrast, there was no change in the oxidation state of Pu in the solution nor on kaolinite after exposure to Pu(VI). SEM-EDS analysis indicated that most of the Pu in the mixture was associated with the bacteria. These results suggest that U(VI) and Pu(VI) preferentially are sorbed to bacterial cells in the presence of kaolinite clay, and that the mechanism of accumulation of U and Pu differs. U(VI) is sorbed directly to the bacterial cells, whereas Pu(VI) first is reduced to Pu(V) and then to Pu(IV), and the latter is associated with the cells. These results have important implications on the migrations of radionuclides around the repository sites of

Radiotracer study of sorption of europium on Gorleben sand from aqueous solutions containing humic substances

International Nuclear Information System (INIS)

Benes, P.; Stamberg, K.; Siroky, L.; Mizera, J.

2002-01-01

The sorption of trace europium, as a trivalent actinide homologue, was studied in the system Gorleben sand - aqueous solution with the aim to elucidate its mechanism. Radiotracer method ( 152/154 Eu) and batch experiments were used. Simultaneously, the distribution of humic substances present in, or added to the system was measured. The evaluation of the sorption was complicated by the adsorption of Eu on the walls of polyethylene vials used for the experiments, which was rather high and had to be taken into consideration. It has been found that Eu sorption on Gorleben sand increases from pH 2 to pH 5-7 and then it decreases. The decrease is due to the complexation of Eu with humic substances leached from Gorleben sand at pH>7. The position of the sorption maximum depends on the composition of the solution and on the liquid-to-solid ratio. It is shifted to lower pH values in the presence of added humic acid (HA), which enhances Eu sorption at low PH values and suppresses it at pH values higher than 5. The regions of the enhancing/suppressing effects coincidence with the high/low adsorption of HA on Gorleben sand, respectively. The increasing ionic strength (from 0.01 to 0.1) and europium concentration (3.4 x 10 -8 to 9.3 x 10 -7 mol/l) suppress the relative sorption (expressed in %) at low pH values and enhance it at pH>6-8. Addition of carbonates (5 x 10 -3 mol/l) supports Eu sorption at pH>7.5 so that no decrease with pH is observed till pH 9. Alkaline leaching of the sand significantly changes most of the effects found. These results were qualitatively interpreted and conclusions were drawn on the mechanism of the sorption. (author)

Radionuclide transfer

International Nuclear Information System (INIS)

Gerber, G.B.

1993-01-01

The research project described here had the aim to obtain further information on the transfer of nuclides during pregnancy and lactation. The tests were carried out in mini-pigs and rats receiving unchanging doses of radionuclides with the food. The following findings were revealed for the elements examined: Fe, Se, Cs and Zn were characterized by very high transfer levels in the mother, infant and foetus. A substantial uptake by the mother alone was observed for Co, Ag and Mn. The uptake by the foetus and infant here was 1 to 10 times lower. A preferential concentration in certain tissues was seen for Sr and Tc; the thyroid levels of Tc were about equally high in mothers and infants, while Sr showed less accumulation in the maternal bone. The lanthanide group of substances (Ce, Eu and Gd as well as Y and Ru) were only taken up to a very limited extent. The uptake of the examined radionuclides (Fe, Co, Ag, Ce) with the food ingested was found here to be ten times greater in rats as compared to mini-pigs. This showed that great caution must be observed, if the behaviour of radionuclides in man is extrapolated from relevant data obtained in rodents. (orig./MG) [de

Radionuclides in the study of marine processes

International Nuclear Information System (INIS)

Kershaw, P.J.; Woodhead, D.S.

1991-01-01

For many years, the radioactive properties of the naturally occurring radionuclides have been used to determine their distributions in the marine environment and, more generally, to gain an understanding of the dynamic processes which control their behaviour in attaining these distributions. More recently the inputs from human activities of both natural and artificial (i.e. man-made) radionuclides have provided additional opportunities for the study of marine processes on local, regional and global scales. The primary objective of the symposium is to provide a forum for an open discussion of the insights concerning processes in the marine environment which can be gained from studies of radionuclide behaviour. Papers have been grouped within the following principal themes; the uses of radionuclides as tracers of water transport; scavenging and particulate transport processes in the oceans as deduced from radionuclide behaviour; processes in the seabed and radionuclides in biological systems. (Author)

Chemical speciation of radionuclides migrating in groundwaters

International Nuclear Information System (INIS)

Robertson, D.; Schilk, A.; Abel, K.; Lepel, E.; Thomas, C.; Pratt, S.; Cooper, E.; Hartwig, P.; Killey, R.

1994-04-01

In order to more accurately predict the rates and mechanisms of radionuclide migration from low-level waste disposal facilities via groundwater transport, ongoing studies are being conducted at field sites at Chalk River Laboratories to identify and characterize the chemical speciation of mobile, long-lived radionuclides migrating in groundwaters. Large-volume water sampling techniques are being utilized to separate and concentrate radionuclides into particular, cationic, anionic, and nonionic chemical forms. Most radionuclides are migrating as soluble, anionic species that appear to be predominantly organoradionuclide complexes. Laboratory studies utilizing anion exchange chromatography have separated several anionically complexed radionuclides, e.g., 60 Co and 106 Ru, into a number of specific compounds or groups of compounds. Further identification of the anionic organoradionuclide complexes is planned utilizing high resolution mass spectrometry. Large-volume ultra-filtration experiments are characterizing the particulate forms of radionuclides being transported in these groundwaters

Treatment techniques for the removal of radioactive contaminants from drinking water

International Nuclear Information System (INIS)

Logsdon, Gary S.

1978-01-01

Maximum contaminant levels have been set for radioactive contaminants, as required by the Safe Drinking Water Act (PL 93-523). Treatment techniques are available for removing radium and beta-gamma emitters. Presently-used methods of removing radium-226 are precipitative lime softening (80-90% removal) ion exchange softening (95% removal) and reverse osmosis (95% removal). The 5 p Ci/l limit for radium can be met with conventional technology for raw waters in the 5-100 p Ci/l concentration range. Treatment for removal of beta or gamma emitters must be based upon chemical rather than radioactive characteristics of the contaminant. Reverse osmosis can remove a broad spectrum of ions and molecules from water, so it is the process most likely to be used. The maximum contaminant level for beta and gamma radioactivity is an annual dose equivalent to the total body or any organ not to exceed 4 m rem/year. The fate of radionuclides after removal from drinking water should be considered. Presently radium is disposed with other process wastes at softening plants removing radium. Confinement and disposal as a radioactive waste would be very expensive. (author)

Determination of the hydrolysis constants of Europium (III), in ion strength media 4, 5 and 6 M NaClO{sub 4} at 303 K; Determinacion de las constantes de hidrolisis del Europio (III), en medios de fuerza ionica 4, 5 y 6 M de NaClO{sub 4} a 303 K

Energy Technology Data Exchange (ETDEWEB)

Alvarado B, A.; Jimenez R, M.; Solache R, M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

1999-07-01

This work was made with the purpose to complete information about the hydrolysis constants of Europium (III) in high ion strength media. So it was determined at a ion forces media 4, 5 and 6 M of sodium perchlorate at 303 K. The method used was the potentiometric with the aid of the Super quad computer program. In high ion strength media, the measurements of p H do not correspond directly to negative logarithm of the concentration of hydrogen ions, by this it is necessary to calibrate the electrode in these conditions. The Europium was hydrolized at pC{sub H} values greater 6 in all cases. The potentiometric method used under the described experimental conditions is adequate to determine the hydrolysis constants of Europium (III). According to the results and diagrams of chemical species of Europium obtained we can conclude that the hydrolysis constants, differ by its distribution but not in its identity. (Author)

Mobility and Bioavailability of Radionuclides in Soils

International Nuclear Information System (INIS)

Iurian, A.; Olufemi Phaneuf, M.; Mabit, L.

2016-01-01

It is crucial to understand the behavior of radionuclides in the environment, their potential mobility and bioavailability related to long-term persistence, radiological hazards, and impact on human health. Such key information is used to develop strategies that support policy decisions. The environmental behavior of radionuclides depends on ecosystem characteristics. A given soil’s capacity to immobilize radionuclides has been proved to be the main factor responsible for their resulting activity concentrations in plants. The mobility and bioavailability of radionuclides in soils is complex, depending on clay-sized soil fraction, clay mineralogy, organic matter, cation exchange capacity, pH and quantities of competing cations. Moreover, plant species have different behaviors regarding radionuclide absorption depending on soil and plan characteristics

Radionuclides deposition over Antarctica

International Nuclear Information System (INIS)

Pourchet, M.; Magand, O.; Frezzotti, M.; Ekaykin, A.; Winther, J.-G.

2003-01-01

A detailed and comprehensive map of the distribution patterns for both natural and artificial radionuclides over Antarctica has been established. This work integrates the results of several decades of international programs focusing on the analysis of natural and artificial radionuclides in snow and ice cores from this polar region. The mean value (37±20 Bq m -2 ) of 241 Pu total deposition over 28 stations is determined from the gamma emissions of its daughter 241 Am, presenting a long half-life (432.7 yrs). Detailed profiles and distributions of 241 Pu in ice cores make it possible to clearly distinguish between the atmospheric thermonuclear tests of the fifties and sixties. Strong relationships are also found between radionuclide data ( 137 Cs with respect to 241 Pu and 210 Pb with respect to 137 Cs), make it possible to estimate the total deposition or natural fluxes of these radionuclides. Total deposition of 137 Cs over Antarctica is estimated at 760 TBq, based on results from the 90-180 deg. East sector. Given the irregular distribution of sampling sites, more ice cores and snow samples must be analyzed in other sectors of Antarctica to check the validity of this figure

Radionuclides in the food chain

International Nuclear Information System (INIS)

Harley, J.H.; Schmidt, G.D.

1988-01-01

Radionuclides in the Food Chain reviews past experience in meeting the challenge of radionuclide contamination of foodstuffs and water sources and, in the wake of the reactor accidents at Chernobyl and Three Mile Island, presents current concepts and programs relating to measurement, surveillance, effects, risk management, evaluation guidelines, and control and regulatory activities. This volume, based on a symposium sponsored by the International Life Sciences Institute in association with the International Institute for Applied Systems Analysis, which brought together both radiation experts and food industry policymakers, examines such vital topics as structural problems in large-scale crisis-managment systems; dose assessment from man-made sources; international recommendations on radiation protection; airborne contamination, as well as aquatic and soilborne radionuclides; food-chain contamination from testing nuclear devices; long-term health effects of radionuclides in food and water supplies; and use of mathematical models in risk assessment and management. (orig.)

Europium(II)heptaphosphide EuP/sub 7/

Energy Technology Data Exchange (ETDEWEB)

von Schnering, H G; Wittmann, M

1980-07-01

The novel polyphosphide, EuP/sub 7/, was prepared under controlled conditions by reaction of the elements in salt melts at 750-800 K. EuP/sub 7/ forms black prismatic crystals not attacked by dilute mineral acids and bases. The thermal decomposition yields EuP/sub 3/ at 700 K and in further steps EuP/sub 2/, Eu/sub 3/P/sub 4/ and EuP, respectively. According to the crystal structure as well as the electrical, optical and magnetic properties, EuP/sub 7/ is a semiconductor (Esub(G) = 0.9 eV; Esub(G) (vert) = 1.1 eV) with divalent europium (..mu.. = 7.55 B.M.). The compound crystallizes in the monoclinic space group P 2/sub 1//n with a = 1148.8(7) pm, b = 570.0(3) pm, c = 1061.0(6) pm, and ..beta.. = 106.08/sup 0/(5); (X-ray diffraction data; 1479 hkl; R = 0.031). The P-atoms are connected ((P-P) = 218.0-223.5 pm) to a 2-dimensional infinite polyanionic structure 2sub(infinity)(P/sub 7//sup 2 -/) with homonuclear 3-bonded and 2-bonded P-atoms in the ratio 5 : 2. The polyanionic network contains P/sub 6/-rings (chair conformation) as well as P/sub 8/-rings and P/sub 10/-rings. The Eu-atoms are bonded to 9 P-atoms (1,4,4-polyhedra) with bond distances ranging from 306.6 to 326.6 pm. The Eu-atoms complete the tetrahedral environment of the P-atoms.

Idaho radionuclide exposure study: Literature review

International Nuclear Information System (INIS)

Baker, E.G.; Freeman, H.D.; Hartley, J.N.

1987-10-01

Phosphate ores contain elevated levels of natural radioactivity, some of which is released to the environment during processing or use of solid byproducts. The effect of radionuclides from Idaho phosphate processing operations on the local communities has been the subject of much research and study. The literature is reviewed in this report. Two primary radionuclide pathways to the environment have been studied in detail: (1) airborne release of volatile radionuclides, primarily 210 Po, from calciner stacks at the two elemental phosphorus plants; and (2) use of byproduct slag as an aggregate for construction in Soda Springs and Pocatello. Despite the research, there is still no clear understanding of the population dose from radionuclide emissions, effluents, and solid wastes from phosphate processing plants. Two other potential radionuclide pathways to the environment have been identified: radon exhalation from phosphogypsum and ore piles and contamination of surface and ground waters. Recommendations on further study needed to develop a data base for a complete risk assssment are given in the report

Efficacy of the semiempirical sparkle model as compared to ECP ab-initio calculations for the prediction of ligand field parameters of europium (III) complexes

International Nuclear Information System (INIS)

Freire, Ricardo O.; Rocha, Gerd B.; Albuquerque, Rodrigo Q.; Simas, Alfredo M.

2005-01-01

The second version of the sparkle model for the calculation of lanthanide complexes (SMLC II) as well as ab-initio calculations (HF/STO-3G and HF/3-21G) have been used to calculate the geometries of a series of europium (III) complexes with different coordination numbers (CN=7, 8 and 9), ligating atoms (O and N) and ligands (mono, bi and polydentate). The so-called ligand field parameters, Bqk's, have been calculated from both SMLC II and ab-initio optimized structures and compared to the ones calculated from crystallographic data. The results show that the SMLC II model represents a significant improvement over the previous version (SMLC) and has given good results when compared to ab-initio methods, which demand a much higher computational effort. Indeed, ab-initio methods take around a hundred times more computing time than SMLC. As such, our results indicate that our sparkle model can be a very useful and a fast tool when applied to the prediction of both ground state geometries and ligand field parameters of europium (III) complexes

Test of zircon materials for sorption of europium; Pruebas de materiales circoniferos para sorcion de europio

Energy Technology Data Exchange (ETDEWEB)

Ordonez R, E.; Fernandez V, S.M.; Garcia R, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2003-07-01

In previous works it has already been made notice that some phosphates have the property of sipping radioactive metals in solution, what takes advantage to fabricate reactive barriers that are placed in the repositories of nuclear wastes. In our laboratory it has been obtained to the zirconium silicate (ZrSiO{sub 4}) and the alpha zirconium hydrogen phosphate (Zr(HPO{sub 4}) 2H{sub 2}0) starting from sea sand in an easy and economic way. With the interest of knowing if these compounds can be used in contention barriers the evaluation of their surface properties it is made and of europium sorption. (Author)

Some parameters of radionuclide kinetics

International Nuclear Information System (INIS)

Prokof'ev, O.N.; Smirnov, V.A.; Belen'kij, E.I.

1978-01-01

Numerical values of the rates of radionuclide absorption into, and elimination from, bovine organs were determined. Kinetic rate constants of radionuclides such as 89 Sr, 99 Mo, 131 I, 132 Tl, and 140 Be were calculated. The calculations were done for muscle, liver, and kidney

Radionuclide - Soil Organic Matter Interactions

DEFF Research Database (Denmark)

Carlsen, Lars

1985-01-01

Interactions between soil organic matter, i.e. humic and fulvic acids, and radionuclides of primary interest to shallow land burial of low activity solid waste have been reviewed and to some extent studied experimentally. The radionuclides considered in the present study comprise cesium, strontium...

Radionuclide transport in a single fissure

International Nuclear Information System (INIS)

Eriksen, T.E.

1984-01-01

Radionuclide migration has been studied in natural fissures running parallel to the axes of granitic drill cores. A short pulse of radionuclide solution was injected at one end of the fissure and the temporal change in radionuclide concentration of the eluate measured. At the end of each experiment the fissure was opened and the radionuclide distribution on the fissure surfaces measured. The retardation of 241 Am(III) at pH 8.2 as well as the variation in 235 Np(V) retardation with pH are found to be in good agreement with K d-values obtained in batch experiments. The reduction of (TcO - 4 ) to Tc(IV) leads as expected to increasing retardation.(author)

Solid-phase synthesis of compounds of europium and terbium with nitrogen-containing heterocyclic compounds under mechanical activation

International Nuclear Information System (INIS)

Kalinovskaya, I.V.; Karasev, V.E.

2000-01-01

Effect of solvents and parameters of mechanical treatment on basic regularities of synthesis of rare earth compounds with nitrogen-containing heterocyclic compounds is studied. It is shown that interaction on europium (3) and terbium (3) nitrates with nitrogen-containing heterocyclic compounds leads to formation of compounds of Ln(NO 3 )·2D composition, where Ln=Eu, Tb; D=2,2-dipyridyl, 1,10-phenanthroline, diphenylguanidine. Effect of conditions of mechanical treatment and different additions on process and yield of products is studied. Compounds prepared are characterized by the methods of chemical element analysis, IR spectroscopy and luminescent spectroscopy [ru

Radionuclide migration in water reservoirs

International Nuclear Information System (INIS)

Rodionova, L.F.

1983-01-01

Toxicity degree and radiation effect of different radionuclides depend on multiple factors, whose interaction can strengthen or weaken the effects through the mechanism of nuclide accumulation by hydrobiontes. Stage of development of an aquatic organism, its age, mass and sex as well as lifetime and residence time of the organism in the given medium are of importance. The radionuclide build up depends on illumination, locale of the bioobject residence, on the residence nature. The concentration of radionuclides in aquatic organisms and bionts survival depend on a season, temperature of the residence medium, as well as salinity and mineral composition of water influence

Aligning physics and physiology: Engineering antibodies for radionuclide delivery.