Environmental radioactivity and chemical composition of different types of bee honeys produced at in-house area, egypt

International Nuclear Information System (INIS)

Ramadan, A.B.

2005-01-01

Environmental radioactivity and chemical composition of bee honey varies with the surrounding environment (major floral and soil contamination), which reflects the nutritional value of honey. 23SU, 232Th, 40K, >37Cs, major elements Na, K, Mg and Cl and trace elements Mn, Fe, Zn, F, I, Cu, Co, Ni and Sr as well as toxic elements Cd and Pb -were all determined in different types of bee honey, which include non-floral honey with artificial feeding (syrup-feed honey) and mono-floral honeys (clover honey or sesame honey or orange honey). These elements were also determined in the bee feeds, which include flowers (clover, sesame and orange) and syrup. The results revealed that of all types of honeys and syrup-feed honey exhibited higher natural radioactivity and higher concentrations ofNa, K, Mg, Cl, oMn, Fe, Co, Cd and Pb than in the other honeys. Orange honey contained the lowest natural radioactivity and element concentrations. Clover honey had the lowest toxic element Cd and Pb concentrations (0.02 and 4.2/xg/g, respectively) while sesame honey contained the highest levels of Cd and F (0.7 and 12.9 /ig/g, respectively). Statistical analysis revealed significant correlation between honey and the feed (R= 0.745 to 0.921). Environmental radioactivity and element concentrations in the honey under study were in the safety baseline levels for human consumption

Elements to diminish radioactive accidents; Elementos para disminuir accidentes radiactivos

Energy Technology Data Exchange (ETDEWEB)

Cortes I, M.E.; Ramirez G, F.P. [Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas 152, C.P. 07730 Mexico D.F. (Mexico)

1998-12-31

In this work it is presented an application of the cause-effect diagram method or Ichikawa method identifying the elements that allow to diminish accidents when the radioactive materials are transported. It is considered the transport of hazardous materials which include radioactive materials in the period: December 1996 until March 1997. Among the identified elements by this method it is possible to mention: the road type, the radioactive source protection, the grade driver responsibility and the preparation that the OEP has in the radioactive material management. It is showed the differences found between the country inner roads and the Mexico City area. (Author)

Chemical form of transuranic elements in underground environment and its effect on adsorption

International Nuclear Information System (INIS)

Tanaka, Tomo

1990-01-01

Many of the transuranic elements such as Np, Pu and Am contained in high-level radioactive wastes are highly dangerous to humans and have extremely long lives. Therefore, safety evaluation of them is highly important after their disposal into the ground. Particularly important processes include the migration of these transuranic elements in near and far fields. The migration of a nuclide depends largely on its chemical form in the underground environment. The present report first describes various chemical forms of transuranic elements in underground environments and outlines their migration behaviors. Techniques that have recently become available for determining their chemical forms include photo-acoustic spectroscopy, thermal lensing spectroscopy, laser induced fluorescence, photo-acoustic detection of light scattering, auto-correlation photon spectroscopy, and laser-induced time-resolved spectrofluorometry. Chemical forms of these elements are then discussed focusing on underground environmental conditions, pH-Eh diagram, deposition/dissolution, formation of complex, formation of colloid, and organic complexes. Migration is discussed in relation to ions, insoluble matters, and colloids. (N.K.)

Hazardous chemical and radioactive wastes at Hanford

International Nuclear Information System (INIS)

Keller, J.F.; Stewart, T.L.

1991-07-01

The Hanford Site was established in 1944 to produce plutonium for defense. During the past four decades, a number of reactors, processing facilities, and waste management facilities have been built at Hanford for plutonium production. Generally, Hanford's 100 Area was dedicated to reactor operation; the 200 Area to fuel reprocessing, plutonium recovery, and waste management; and the 300 Area to fuel fabrication and research and development. Wastes generated from these operations included highly radioactive liquid wastes, which were discharged to single- and double-shell tanks; solid wastes, including both transuranic (TRU) and low-level wastes, which were buried or discharged to caissons; and waste water containing low- to intermediate-level radioactivity, which was discharged to the soil column via near-surface liquid disposal units such as cribs, ponds, and retention basins. Virtually all of the wastes contained hazardous chemical as well as radioactive constituents. This paper will focus on the hazardous chemical components of the radioactive mixed waste generated by plutonium production at Hanford. The processes, chemicals used, methods of disposition, fate in the environment, and actions being taken to clean up this legacy are described by location

Hazardous chemical and radioactive wastes at Hanford

International Nuclear Information System (INIS)

Keller, J.F.; Stewart, T.L.

1993-01-01

The Hanford Site was established in 1944 to produce plutonium for defense. During the past four decades, a number of reactors, processing facilities, and waste management facilities were built at Hanford for plutonium production. Generally, Hanford's 100 Area was dedicated to reactor operation; the 200 Areas to fuel reprocessing, plutonium recovery, and waste management; and the 300 Area to fuel fabrication and research and development. Wastes generated from these operations included highly radioactive liquid wastes, which were discharged to single- and double-shell tanks; solid wastes, including both transuranic and low-level wastes, which were buried or discharged to caissons; and waste water containing low- to intermediate-level radioactivity, which was discharged to the soil column via near-surface liquid disposal units such as cribs, ponds, and retention basins. Virtually all of the wastes contained hazardous chemicals as well as radioactive constituents. This paper focuses on the hazardous chemical components of the radioactive mixed waste generated by plutonium production at Hanford. The processes, chemicals used, methods of disposition, fate in the environment, and actions being taken to clean up this legacy are described by location

Radioactivity in the pelagic fish. II. Group separation of radioactive elements in fish tissues

Energy Technology Data Exchange (ETDEWEB)

Yamada, K; Tozawa, H; Amano, K; Takase, A

1955-01-01

Analytical group separation was performed with various ashed tissues of some fishes exposed to radioactive ash. The radioactivity was particularly large with elements belonging to the 3rd group, both A and B subgroups. The 2nd group showed considerable activity in pyloric ceca and kidney of Skipjacks. The radioactivity of the 1st and 4th groups was detected in some tissues; the 5th group showed slight activity.

Storage container for radioactive fuel elements

International Nuclear Information System (INIS)

1984-01-01

The interim storage cask for spent fuel elements or the glass moulds for high-level radioactive waste are made up of heat-resistant, reinforced concrete with chambers and highgrade steel lining. Cooling systems with natural air circulation are connected with the chambers. (HP) [de

Transportation of radioactive elements

International Nuclear Information System (INIS)

Thubert, Francis; Rentien, Guy; Jacquet, Michel

1981-01-01

The production and marketing of artificial radioactive elements engaged in by the 'Office des Rayonnements Ionisants' requires the use of specially designed packagings and assorted means of transport. The authors begin by describing the different kinds of products involved and the forms of packagings needed, and go on to discuss the various means of transport used, underlining the fact that, in terms of number and gravity, the incidents that have occurred to date have indeed been few and far between [fr

Measurement of fertilizers induced radioactivity in tobacco plants and elemental analysis using ICAP–AES

International Nuclear Information System (INIS)

Chauhan, Pooja; Chauhan, R.P.

2014-01-01

It is widely accepted that tobacco smoke is the leading cause of lung cancer worldwide. The alpha radioactive content present in tobacco smoke and increasing number of lung cancer cases explain the importance of investigation. The use of different fertilizers may cause alteration in the metabolism of plants causing different response towards uptake of different element and radionuclides. In the present study, the estimation of alpha radioactivity induced by use of different fertilizers in tobacco leaves was made using solid state nuclear track detector (LR-115) to identify the relative presence of radionuclides in the plants. The radon exhalation rates from the tobacco plant were carried out to confirm the presence of radium or emission of radon from plant. The elemental analysis of tobacco plant by inductively coupled argon plasma atomic emission spectrometry provides a way to understand the difference occurred in metabolism caused by the use of fertilizers. The alpha track densities were found to vary with nature of fertilizers added to the soil and an increase was also observed with time. The radon mass exhalation rates in various tobacco plants were found to vary with type of fertilizers used. - Highlights: • The study is related to alpha radioactivity measurements in tobacco plants. • The radon mass exhalation rates in various tobacco plants were also measured. • Study is related to analysis of chemical elements in different fertilized tobacco samples

Radioactive elements and earthworms in contaminated soils

International Nuclear Information System (INIS)

Suleymanova, A.S.; Abdullayev, A.S.; Ahmadov, G.S.; Naghiyev, J.A.; Samadov, P.A.

2010-11-01

Earthworms are one of the indispensable soil animals which treat soil with letting it through their gut and help increasing soil fertility. The effect of radioactive elements and comparative effect of heavy metals to the vital functions of earthworms were determined in laboratory conditions. Experiments were continued for a month, and first of all, each soil type, grey-brown soil from Ramana iodine plant territory of Baku city, brown soil from Aluminum plant territory of Ganja city, aborigine grey-brown soil of Absheron peninsula, treated with Ra and U salts as model variants and brown soil of Ganja city was analyzed by gamma-spectrometer for radionuclide determining at the beginning and at the end of the experiment. Earthworms (Nicodrilus Caliginosus Sav.trapezoides) aboriginal for Absheron peninsula and plant residues were added to the soil. At the end of the month the biomass, survival value, coprolite allocation value, food activity and catalase value in earthworms and in soil were determined. The gamma-spectrometric analysis results gave interesting values in coprolites, soils which had been treated through the earthworms' gut. In comparison with the initial variants in experimental results more percent of radioactivity was gathered in coprolites. By this way earthworms absorbed most of radioactive elements and allocated them as coprogenous substances on the upper layer of soil. During absorbing, some percents of radioactive elements were also gathered in gut cells of the earthworms. Thereby determination of some vital functions of earthworms was expedient. Thus, by the instrumentality of these experiments we can use earthworms for biodiagnosis and for bioremediation of contaminated soils with radionuclides and heavy metals.

DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

Energy Technology Data Exchange (ETDEWEB)

NA

2004-11-22

The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this modeling activity is to predict dissolved concentrations or solubility limits for 14 elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) important to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are in the form of tabulated functions with pH and log (line integral) CO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. The output data from this report are fundamental inputs for Total System Performance Assessment for the License Application (TSPA-LA) to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for all of the actinides. These models cover broad ranges of environmental conditions so that they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or otherwise addressed.

Process for improving the separation efficiency in the isolation of radioactive isotopes in elementary or chemically bonded form from liquids and gases

International Nuclear Information System (INIS)

Schmidberger, R.; Kirch, R.; Kock, W.

1986-01-01

In the process for the improvement of the separation efficiency in the isolation of radioactive isotopes in elementary or chemically bonded form from liquids or gases by ion exchange and adsorption, non-radioactive isotopes of the element to be isolated are added to the fluid before the isolation, whereas at the same time a large surplus of the non-radioactive isotopes to the radioactive isotopes is achieved by addition of only small quantities of compounds of the non-radioactive isotopes. (orig./RB) [de

Report on the disposal of radioactive wastes and spent fuel elements from Baden-Wuerttemberg

International Nuclear Information System (INIS)

2017-04-01

The report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg covers the following issues: legal framework for the nuclear disposal; producer of spent fuels and radioactive wastes in Baden- Report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg; low- and medium-level radioactive wastes (non heat generating radioactive wastes); spent fuels and radioactive wastes from waste processing (heat generating radioactive wastes); final disposal.

Chemical treatment of radioactive wastes

International Nuclear Information System (INIS)

Pottier, P.E.

1968-01-01

This is the third manual of three commissioned by the IAEA on the three principal techniques used in concentrating radioactive liquid wastes, namely chemical precipitation, evaporation and ion exchange. The present manual deals with chemical precipitation by coagulation-flocculation and sedimentation, commonly called ''chemical treatment'' of low-activity wastes. Topics discussed in the manual are: (i) principles of coagulation on flocculation and sedimentation and associated processes; (ii) process and equipment; (iii) conditioning and disposal of flocculation sludge; (iv) sampling and the equipment required for experiments; and (v) factors governing the selection of processes. 99 refs, 17 figs, 4 tabs

Radioactivity in Chemical Fertilizers

International Nuclear Information System (INIS)

Jankovic, M.; Nikolic, J.; Pantelic, G.; Rajacic, M.; Sarap, N.; Todorovic, D.

2013-01-01

The fertilizers are essential in agriculture as they supply nutrients to the farming fields. One of the sources of radioactivity other than those of natural origin is mainly due to extensive use of fertilizers. The concentrations of natural radionuclides, 40K, 226Ra, 238U and 235U in different chemical fertilizers, which are part of the regular control of imported goods from the border crossing were analyzed using gamma spectrometry with a high purity germanium (HPGe) detector, relative efficiency 20 %, in order to assess the implications of the extended use of chemical fertilizers. Measurements were performed at Vinca Institute, Radiation and Environmental Protection Department. The obtained results show remarkable wide variations in the radioactivity contents of different samples. The mean (ranges) of specific activities for gamma activity of those fertilizer samples for 40K, 226Ra, 238U and 235U are 4857 (23 - 12 324) Bq/kg, 87 (4-393) Bq/kg, 220 (26-1145) Bq/kg and 15 (1.6-53) Bq/kg, respectively. The radium equivalent activity (Ra eq ) as well as the external absorbed gamma dose rate (D) for all samples was also calculated.(author)

Disposal of flow-level radioactive waste in Belgium: A safety analysis for inorganic chemotoxic elements

International Nuclear Information System (INIS)

Mallants, D.; Volckaert, G.; Marivoet, J.; Neerdael, B.

2000-01-01

Low-level radioactive waste often contains large quantities of inorganic chemical substances. Due attention should therefore be given to the safety implications of both the radiological and chemical substances in the waste. Our study develops the safety assessment methodology for surface disposal with emphasis on the potential effects of inorganic nonradiological elements on human health. Contamination of groundwater was considered as the major exposure pathway. The applied methodology first screens all elements on the basis of five criteria. Conservative screening calculations were used to screen out the elements that do not pose danger to humans, and to select those that could have a negative impact and thus require further analysis. The latter was done by first calculating the elemental mass fluxes out of the repository and into the aquifer followed by the calculation of groundwater concentrations. The results showed that on the basis of the screening calculations, 75% of all elements could be classified as non-hazardous. The detailed calculations showed that the majority of the remaining elements had groundwater concentrations below the drinking water or groundwater standards. The results further showed that for a few elements the maximum groundwater concentration was above the standard, but below the background concentrations. (author)

Some problems of risk assessment in cases of environmental radioactive and chemical contamination in regions of the Ural radioactive trail

International Nuclear Information System (INIS)

Kryshev, I.I.; Isaeva, L.N.; Sazykina, T.G.

1995-01-01

A methodology of risk assessment if being developed to permit the analysis of possible consequences of radioactive and chemical environment contamination on the territory of the Urals radioactive trail. The assessment of hazards from radioactive contamination of the Techa river (Muslyumovo) has been carried out. A comparison of radioactive and chemical risks for the population of Kasli has been made

Chemical and radioactivity study of sea alga distribution along the Syrian coast

International Nuclear Information System (INIS)

Al-Masri, M. S.; Mamish, S.; Budeir, Y.

2001-11-01

Three types of sea alga distributed along the Syrian coast have been studied from the chemical and radioactivity point of view. Results have shown the metals that red alga contains the highest levels of Ca and Mg while brown alga were found to contain relatively high concentrations of other elements and non metals such as Cl, I and Br. In addition, 137 Cs concentrations in all the analyzed sample were low while the levels of naturally occurring radionuclides such as 210 Po, 210 Pb and radium isotopes were found to be high in red alga which indicates their selectivity to these isotopes. On the other hand, brown alga and especially Cysteseira has shown a clear selectivity for some trace elements such as As, Cr, Cd, Cu and Co, this selectivity may encourage the use of brown alga as biological indicator for trace elements pollution. (author)

Radioactive particles revealed by electron microscopy. Chemical and physical properties of radioactive particles in aerosol samples emitted during the early stage of Fukushima Dai-ichi Nuclear Power Plant accident

International Nuclear Information System (INIS)

Adachi, Kouji

2015-01-01

Water-insoluble radioactive materials emitted during an early stage of the Fukushima Dai-ichi Nuclear Power Plant accident in 2011 were identified, and their chemical and physical properties were characterized as particulate matters. In this report, studies on radioactive particles collected from filter samples in Tsukuba on March 14–15, 2011 are summarized. Their compositions, chemical states, sizes, shapes, crystallinity, and hygroscopicity were analyzed using microscopic analyses such as electron microscopy and synchrotron with a micro-beam. The results indicate that they include Cs, Fe, and Zn as well as elements from fission products and are water insoluble, spherical-glassy particles with ca. 2 micrometer in size. Understanding of their detailed properties is significant to improve the numerical models during the accident and to understand their occurrences in soil as well as the accident itself. In addition to the water-insoluble radioactive materials, water-soluble radioactive materials, which were likely emitted in different events during the accident, should be investigated to have comprehensive understanding of the accident and its environmental effects. More samples from various environments such as soil will be needed, and more detailed chemical and physical analyses will help to understand their formation process, influences on human health, and long term decrements in ambient conditions. (author)

Element interactions and soil properties affecting the soil-to-plant transfer of six elements relevant to radioactive waste in boreal forest

International Nuclear Information System (INIS)

Roivainen, Paeivi; Makkonen, Sari; Holopainen, Toini; Juutilainen, Jukka

2012-01-01

Cobalt (Co), lead (Pb), molybdenum (Mo), nickel (Ni), uranium (U), and zinc (Zn) are among the elements that have radioactive isotopes in radioactive waste. Soil-to-plant transfer is a key process for possible adverse effects if these radionuclides are accidentally released into the environment. The present study aimed at investigating factors affecting such transfer in boreal forest. The plant species studied were blueberry (Vaccinium myrtillus), May lily (Maianthemum bifolium), narrow buckler fern (Dryopteris carthusiana), rowan (Sorbus aucuparia) and Norway spruce (Picea abies). Regression analyses were carried out to investigate the effects of the chemical composition and physical properties of soil on the soil-to-leaf/needle concentration ratios of Co, Mo, Ni, Pb, U and Zn. Soil potassium (K), magnesium (Mg), manganese (Mn), phosphorus (P) and sulphur (S) concentrations were the most important factors affecting the soil-to-plant transfer of the elements studied. Soil clay and organic matter contents were found to significantly affect plant uptake of Mo, Pb and U. Knowledge of the effects of these factors is helpful for interpretation of the predictions of radioecological models describing soil-to-plant transfer and for improving such models. (orig.)

Element interactions and soil properties affecting the soil-to-plant transfer of six elements relevant to radioactive waste in boreal forest

Energy Technology Data Exchange (ETDEWEB)

Roivainen, Paeivi; Makkonen, Sari; Holopainen, Toini; Juutilainen, Jukka [University of Eastern Finland, Department of Environmental Science, Kuopio (Finland)

2012-03-15

Cobalt (Co), lead (Pb), molybdenum (Mo), nickel (Ni), uranium (U), and zinc (Zn) are among the elements that have radioactive isotopes in radioactive waste. Soil-to-plant transfer is a key process for possible adverse effects if these radionuclides are accidentally released into the environment. The present study aimed at investigating factors affecting such transfer in boreal forest. The plant species studied were blueberry (Vaccinium myrtillus), May lily (Maianthemum bifolium), narrow buckler fern (Dryopteris carthusiana), rowan (Sorbus aucuparia) and Norway spruce (Picea abies). Regression analyses were carried out to investigate the effects of the chemical composition and physical properties of soil on the soil-to-leaf/needle concentration ratios of Co, Mo, Ni, Pb, U and Zn. Soil potassium (K), magnesium (Mg), manganese (Mn), phosphorus (P) and sulphur (S) concentrations were the most important factors affecting the soil-to-plant transfer of the elements studied. Soil clay and organic matter contents were found to significantly affect plant uptake of Mo, Pb and U. Knowledge of the effects of these factors is helpful for interpretation of the predictions of radioecological models describing soil-to-plant transfer and for improving such models. (orig.)

Radioactivity and trace element contents of commercial chewing tobacco

International Nuclear Information System (INIS)

Dafauti, S.; Pulhani, V.; Dahiya, S.; Hegde, A.G.

2007-01-01

Radioactive elements uranium, thorium and their daughters are present ubiquitously in the environment and are transferred to man through various pathways. Both, U and Th can cause radiological and toxic hazards. The ingestion dose pathway calculations involve analysis of all kinds of food or edible materials. A large population in India and Asian subcontinent are addicted to commercially available chewing tobacco. This practice is reported to have lead to increased consequences of cancer. Trace elements (Fe, Co, Mn, Zn etc.) are essential but may also prove to be toxic if present in excess. Besides these the hazards of heavy elements like Pb and Cd have also increased in the current polluted environment. In this study most of the commercially available brands of gutkha and chewing tobacco were collected. The radioactive elements U and Th were analyzed in them by Radiochemical Neutron Activation Analysis technique. Trace elements Fe, Co, Mn, Zn, and toxic heavy elements Pb, Cd, Ni etc. were analyzed by Atomic Absorption Spectrophotometry. The levels of Th and U were in the range 0.02-0.11 mg/g and 0.02-0.08 mg/g respectively. The cancer risk due to U, Th, Pb and Cd were calculated and are found to be low. (author)

Principles for disposal of radioactive and chemical hazardous wastes

International Nuclear Information System (INIS)

Merz, E. R.

1991-01-01

The double hazard of mixed wastes is characterized by several criteria: radioactivity on the one hand, and chemical toxicity, flammability, corrosiveness as well as chemical reactivity on the other hand. Chemotoxic waste normally has a much more complex composition than radioactive waste and appears in much larger quantities. However, the two types of waste have some properties in common when it comes to their long-term impact on health and the environment. In order to minimize the risk associated with mixed waste management, the material assigned for ultimate disposal should be thoroughly detoxified, inertized, or mineralized prior to conditioning and packaging. Good control over the environmental consequence of waste disposal requires that detailed criteria for tolerable contamination should be established, and that compliance with these criteria can be demonstrated. For radioactive waste, there has been an extensive international development of criteria to protect human health. For non-radioactive waste, derived criteria exist only for a limited number of substances

DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

Energy Technology Data Exchange (ETDEWEB)

P. Bernot

2005-07-13

The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this activity is to predict dissolved concentrations or solubility limits for elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) relevant to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are provided in the form of tabulated functions with pH and log fCO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. Even though selection of an appropriate set of radionuclides documented in Radionuclide Screening (BSC 2002 [DIRS 160059]) includes actinium, transport of Ac is not modeled in the total system performance assessment for the license application (TSPA-LA) model because of its extremely short half-life. Actinium dose is calculated in the TSPA-LA by assuming secular equilibrium with {sup 231}Pa (Section 6.10); therefore, Ac is not analyzed in this report. The output data from this report are fundamental inputs for TSPA-LA used to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for the actinides discussed in this report. These models cover broad ranges of environmental conditions so they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or

DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

International Nuclear Information System (INIS)

P. Bernot

2005-01-01

The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this activity is to predict dissolved concentrations or solubility limits for elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) relevant to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are provided in the form of tabulated functions with pH and log fCO 2 as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. Even though selection of an appropriate set of radionuclides documented in Radionuclide Screening (BSC 2002 [DIRS 160059]) includes actinium, transport of Ac is not modeled in the total system performance assessment for the license application (TSPA-LA) model because of its extremely short half-life. Actinium dose is calculated in the TSPA-LA by assuming secular equilibrium with 231 Pa (Section 6.10); therefore, Ac is not analyzed in this report. The output data from this report are fundamental inputs for TSPA-LA used to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for the actinides discussed in this report. These models cover broad ranges of environmental conditions so they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or otherwise

Chemical fractionation of radionuclides and stable elements in aquatic plants of the Yenisei River.

Science.gov (United States)

Bolsunovsky, Alexander

2011-09-01

The Yenisei River is contaminated with artificial radionuclides released by one of the Russian nuclear plants. The aquatic plants growing in the radioactively contaminated parts of the river contain artificial radionuclides. The aim of the study was to investigate accumulation of artificial radionuclides and stable elements by submerged plants of the Yenisei River and estimate the strength of their binding to plant biomass by using a new sequential extraction scheme. The aquatic plants sampled were: Potamogeton lucens, Fontinalis antipyretica, and Batrachium kauffmanii. Gamma-spectrometric analysis of the samples of aquatic plants has revealed more than 20 radionuclides. We also investigated the chemical fractionation of radionuclides and stable elements in the biomass and rated radionuclides and stable elements based on their distribution in biomass. The greatest number of radionuclides strongly bound to biomass cell structures was found for Potamogeton lucens and the smallest for Batrachium kauffmanii. For Fontinalis antipyretica, the number of distribution patterns that were similar for both radioactive isotopes and their stable counterparts was greater than for the other studied species. The transuranic elements (239)Np and (241)Am were found in the intracellular fraction of the biomass, and this suggested their active accumulation by the plants.

Recommendations for sampling for prevention of hazards in civil defense. On analytics of chemical, biological and radioactive contaminations. Brief instruction for the CBRN (chemical, biological, radioactive, nuclear) sampling

International Nuclear Information System (INIS)

Bachmann, Udo; Biederbick, Walter; Derakshani, Nahid

2010-01-01

The recommendation for sampling for prevention of hazards in civil defense is describing the analytics of chemical, biological and radioactive contaminations and includes detail information on the sampling, protocol preparation and documentation procedures. The volume includes a separate brief instruction for the CBRN (chemical, biological, radioactive, nuclear) sampling.

Systematic studies of radioactive elements in various rocks in northern Thailand

Energy Technology Data Exchange (ETDEWEB)

Wattananikorn, K; Teeyasoontranont, V; Vilaithong, T; Lerdthusnee, S

1985-12-31

An investigation into the concentrations of the main heat producing radioactive elements, uranium, thorium and potassium in various rock samples was carried out by gamma ray spectrometry. The samples included igneous, metamorphic and sedimentary rocks of different ages. They were collected mainly from the northern part of the country. Results of the investigation show relatively high concentrations of radioactive elements in most rock types, compared to the average values commonly cited. However, for granitic rocks the values obtained are, more or less, comparable to those obtained by Amnuaychai Thienprasert and his colleagues, who worked in the same area using different methods of investigation. Apart from that granitic samples of triassic and cretaceous ages also have a similar radioactive elements concentration to those of the Darby pluton in Southeastern Seward Peninsular, Alaska, the Granite Mountain in Wyoming and the Conway Granite of New Hampshire which has been cited as a low-grade uranium-thorium resource. As a consequence of such high radioactive element concentrations, heat generations of most rock samples investigated are much higher than reported average values. The heat generations seem to have some influence on the nature of heat sources of hot springs in northern Thailand, especially at Ban Pong, Nam Ron hot spring Amphoe Mae Chan. Furthermore the radiogenic heat productions also affect to a great extent surface heat flow in the region provided that the radioactive element concentrations do not decrease with depth. Surface heat flow in northern Thailand was recently reported to be very high compared to the average value of the earth. This high heat flow was suspected to be caused by extensional tectonics resulting indirectly from sea-floor spreading in the Andaman Sea during the last 10 million years. However, from this study it can be shown that heat generations could be another factor which has much influence on the value of the surface heat flow.

Chemical decontamination method for radioactive metal waste

International Nuclear Information System (INIS)

Onuma, Tsutomu; Akimoto, Hidetoshi

1991-01-01

The invention relates to a decontamination method for radioactive metal waste products derived from equipment that handles radioactive materials whose surfaces have been contaminated; in particular it concerns a decontamination method that reduces the amount of radioactive waste by decontaminating radioactive waste substances to a level of radioactivity in line with normal waste products. In order to apply chemical decontamination to metal waste products whose surfaces are divided into carbon steel waste and stainless steel waste; the carbon steel waste is treated using only a primary process in which the waste is immersed in a sulfuric acid solution, while the stainless steel waste must be treated with both the primary process and then electrolytically reduces it for a specific length of time and a secondary process that uses a solution of sulfuric acid mixed with oxidizing metal salts. The method used to categorize metal waste into carbon steel waste and stainless steel waste involves determining the presence, or absence, of magnetism. Voltage is applied for a fixed duration; once that has stopped, electrolytic reduction repeats the operative cycle of applying, then stopping voltage until the potential of the radioactive metal waste is retained in the active region. 1 fig. 2 tabs

Atlantic Forest. A natural reservoir of chemical elements

International Nuclear Information System (INIS)

De Franca, E.J.; De Nadai Fernandes, E.A.; Bacchi, M.A.; Elias, C.

2008-01-01

The accumulation of chemical elements in biological compartments is one of the strategies of tropical species to adapt to a low-nutrient soil. This study focuses on the Atlantic Forest because of its eco-environmental importance as a natural reservoir of chemical elements. About 20 elements were determined by INAA in leaf, soil, litter and epiphyte compartments. There was no seasonality for chemical element concentrations in leaves, which probably indicated the maintenance of chemical elements in this compartment. Considering the estimated quantities, past deforestation events could have released large amounts of chemical elements to the environment. (author)

Chemically reducing decontamination method for radioactive metal

International Nuclear Information System (INIS)

Tanaka, Akio; Onuma, Tsutomu; Sato, Hitoshi.

1994-01-01

The present invention concerns a decontamination method of electrolytically reducing radioactive metal wastes, then chemically dissolving the surface thereof with a strong acid decontaminating solution. This method utilizes dissolving characteristics of stainless steels in the strong acid solution. That is, in the electrolytic reduction operation, a portion of the metal wastes is brought into contact with a strong acid decontaminating solution, and voltage and current are applied to the portion and keep it for a long period of time so as to make the potential of the immersed portion of the metal wastes to an active soluble region. Then, the electrolytic reduction operation is stopped, and the metal wastes are entirely immersed in the decontaminating solution to decontaminate by chemical dissolution. As the decontaminating solution, strong acid such as sulfuric acid, nitric acid is used. Since DC current power source capacity required for causing reaction in the active soluble region can be decreased, the decontamination facility can be minimized and simplified, and necessary electric power can be saved even upon decontamination of radioactive metal wastes made of stainless steels and having a great area. Further, chemical dissolution can be conducted without adding an expensive oxidizing agent. (N.H.)

Features of adsorbed chemical elements and their isotopes distribution in iodine air filters AU-1500 of nuclear power plant

International Nuclear Information System (INIS)

Neklyudov, I.M.; Dovbnya, A.N.; Dikiy, N.P.; Ledenyov, O.P.; Lyashko, Yu.V.

2013-01-01

The main aim of research is to investigate the physical features of spatial distribution of the adsorbed chemical elements and their isotopes in the granular filtering medium in the iodine air filters of the type of AU-1500 in the forced-exhaust ventilation at the nuclear power plant. The ?-activation analysis method is applied to accurately characterize the distribution of the adsorbed radioactive chemical elements and their isotopes in the granular filtering medium in the AU-1500 iodine air filter after its long term operation at the nuclear power plant. The typical spectrum of the detected chemical elements and their isotopes in the AU-1500 iodine air filter, which was exposed by the irradiation of bremsstrahlung gamma-quantum producing by the accelerating electrons in the tantalum target, are obtained. The spatial distributions of the detected chemical element 127 I and some other chemical elements and their isotopes in the layer of absorber, which was made of the cylindrical coal granules of the type of SKT-3, in the AU-1500 iodine air filter are also researched. The possible influences by the standing wave of air pressure in the iodine air filter on the spatial distribution of the chemical elements and their isotopes in the iodine air filter are discussed. The comprehensive analysis of obtained research results on the distribution of the adsorbed chemical elements and their isotopes in the absorber of iodine air filter is performed.

Piracicaba River Basin: evaluation of chemical elements in deep sediment profile by INAA

Energy Technology Data Exchange (ETDEWEB)

França, Elvis J. de; Santos, Robson A.; Santos, Katarine M. Barbosa; Silva, Gleyce K. A. [Centro Regional de Ciencias Nucleares do Nordeste (DIAMB/CRCN-NE/CNEN-PE), Recife, PE (Brazil). Div, de Monitoração Ambiental; Fernandes, Elisabete A. de Nadai; Rodrigues, Vanessa S.; Cavalca, Isabel P.O., E-mail: ejfranca@cnen.gov.br, E-mail: lis@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

2017-07-01

Many hydrographic basins have been impacted by anthropogenic sources, the Piracicaba River Basin of the State of São Paulo, is one of that. The total concentrations of chemical elements in deep sediments of basin may be indicate those available in ecosystem. Therefore, in this research concentration of chemical elements on deep sediment profile sampled of Piracicaba River Basin was determined by k0-Instrumental Neutron Activation Analysis. After collecting the 60 cm depth profile, samples were obtained by sectioning the sediment profile in 5 cm layers, totalizing 12 samples. Analytical portions were transferred to polyethylene vials for neutron irradiation at the Nuclear Research Reactor IEA-R1 from the Instituto de Pesquisas Energéticas e Nucleares IPEN/CNEN. After waiting for radiation safe levels, irradiated samples were transported to the Radioisotopes Laboratory from the Centro de Energia Nuclear na Agricultura CENA/USP. High Resolution Gamma-Ray Spectrometry using HPGe detectors was applied to measure the induced radioactivity. The chemical element mass fractions and their respective expanded analytical uncertainties (95% confidence level) were determined by k0-INAA using the in-house software Quantu. Geological reference materials were analyzed with samples to evaluate the quality of the analytical procedure. Results indicated the presence of enriched surface sediments (0-10 cm depth) for As, Ba, Ca, Co, Cs, Fe, Sb, Sc, Sr, Yb and Zn, despite no alteration was observed for Eu, Ta and Tb. Therefore, the evaluation of deep sediment profile afford the chemical element dynamics for the Piracicaba Basin. (author)

Piracicaba River Basin: evaluation of chemical elements in deep sediment profile by INAA

International Nuclear Information System (INIS)

França, Elvis J. de; Santos, Robson A.; Santos, Katarine M. Barbosa; Silva, Gleyce K. A.

2017-01-01

Many hydrographic basins have been impacted by anthropogenic sources, the Piracicaba River Basin of the State of São Paulo, is one of that. The total concentrations of chemical elements in deep sediments of basin may be indicate those available in ecosystem. Therefore, in this research concentration of chemical elements on deep sediment profile sampled of Piracicaba River Basin was determined by k0-Instrumental Neutron Activation Analysis. After collecting the 60 cm depth profile, samples were obtained by sectioning the sediment profile in 5 cm layers, totalizing 12 samples. Analytical portions were transferred to polyethylene vials for neutron irradiation at the Nuclear Research Reactor IEA-R1 from the Instituto de Pesquisas Energéticas e Nucleares IPEN/CNEN. After waiting for radiation safe levels, irradiated samples were transported to the Radioisotopes Laboratory from the Centro de Energia Nuclear na Agricultura CENA/USP. High Resolution Gamma-Ray Spectrometry using HPGe detectors was applied to measure the induced radioactivity. The chemical element mass fractions and their respective expanded analytical uncertainties (95% confidence level) were determined by k0-INAA using the in-house software Quantu. Geological reference materials were analyzed with samples to evaluate the quality of the analytical procedure. Results indicated the presence of enriched surface sediments (0-10 cm depth) for As, Ba, Ca, Co, Cs, Fe, Sb, Sc, Sr, Yb and Zn, despite no alteration was observed for Eu, Ta and Tb. Therefore, the evaluation of deep sediment profile afford the chemical element dynamics for the Piracicaba Basin. (author)

Isolation of transplutonium elements from high-level radioactive wastes using diphenyl(dibutylcarbamoylmethyl)phosphine oxide

International Nuclear Information System (INIS)

Chmutova, M.K.; Litvina, M.N.; Pribylova, G.A.; Ivanova, L.A.; Myasoedov, B.F.; Smirnov, I.V.; Shadrin, A.Yu.

1999-01-01

Consequent stages of development of principal technological scheme of extraction separation of transplutonium elements from high-level radioactive wastes of spent fuel reprocessing are presented. Approach to reagent selection from the series of carbamoylmethylphosphine oxides is based. Distribution of transplutonium elements and accompanying elements between model solution of high-level radioactive wastes and solution of reagent in organic solvent is investigated. Methods of separation of transplutonium elements, reextraction of transplutonium elements together with rare earth elements are developed. Principal technological scheme of transplutonium elements separation from nonevaporated raffinates of spent fuel of WWER type reactors and method of separation of transplutonium and rare earth elements in weakly acid reextract with the use of liquid chromatography with free immobile phase are proposed [ru

Physico-chemical and radioactive characterization of TiO2 undissolved mud for its valorization

International Nuclear Information System (INIS)

Gazquez, M.J.; Mantero, J.; Bolivar, J.P.; Garcia-Tenorio, R.; Vaca, F.; Lozano, R.L.

2011-01-01

In order to find a potential valorization of a waste generated in the industrial process devoted to the production of TiO 2 pigments, and as an essential and basic step, this waste must firstly be physically and chemically characterized. Moreover, the content of radioactivity is taken in to account due to it comes from a NORM (Naturally Occurring Radioactive Material) industry. With this end, microscopic studies were performed by applying scanning electron microscopy with X-ray microanalysis (SEM-XRMA), while the mineralogical compositions were carried out by means of the X-ray diffraction (XRD) technique. The concentrations of its major elements were determined by X-ray fluorescence (XRF), while heavy metals and other trace elements were ascertained through Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results obtained for this waste have revealed several lines of research into potential applications. Firstly, with the refractory properties of mineral phases observed leading to a possible use in the ceramics industry or in thermal isolators. And secondly, attending to the characteristic particle-size spectra can be used as an additive in the manufacture of cement and finally, its high concentration of titanium may be used as a bactericide in brick production.

Natural radiation, radioactive waste and chemical risk determinants

International Nuclear Information System (INIS)

Christensen, T.; Mustonen, R.; Edhwall, H.; Hansen, H.; Soerensen, A.; Stranden, E.

1990-01-01

Doses from natural radiation to the population in the Nordic countries are summarized, and man-made modifications of the natural radiation environment are discussed. An account is given for the radiological concequences of energy concervation by reduced ventilation. Risks from possible future releases of radioactivity from final depositories of spent nuclear fuel are compared to the risks from present natural radioactivity in the environment. The possibilities for comparison between chemical and radiological risks are discussed. 104 refs., 36 figs., 47 tabs

Studies on the remediation of environment contaminated with radioactive pollutants using the chemical separation technique

Energy Technology Data Exchange (ETDEWEB)

Kurotaki, Katsumi; Yonehara, Hidenori; Sahoo, S.K. [National Inst. of Radiological Sciences, Chiba (Japan); Ishii, Toshiaki [National Inst. of Radiological Sciences, Hitachinaka, Ibaraki (Japan). Lab. for Radioecology

2001-12-01

Remediation of soil and drinking water contaminated with radioactive nuclides is important for the mitigation of radiation exposure. Then we attempted to construct the remediation system including the dose estimation system using the chemical separation technique to remove pollutants from the environment. The information on air dose rate is important for assessment of risk from the radiation exposure. Then we measured the air dose rate and analysed the relationship between air dose rate and the contamination of soil at the area in Russia (Bryansk district) contaminated by Chernobyl Nuclear Power Plant accident. Moreover, we analysed the soil of Bryansk district on the concentration of rare earth elements, thorium and uranium and on the isotope ratio of strontium. On the other hand, we tried to develop the rapid measurement method of radioactivity of Sr-90 which is one of the dangerous radionuclides, because the method of radioactivity measurement in the literature is too time-consuming. It was reported recently that the molecules containing SH group form the covalent bond with gold atoms at the surface of gold plate and that crown ether compounds have strong affinity to strontium. Then we attempted to synthesize the crown ether containing SH group. In addition, we search the inorganic elements accumulated to special organisms of fishes and other animals in sea in order to find out new reagent for trace elements. Transition metal such as Co, Fe, Ni, Ti, V and Zn were detected from the intracellular granules in the bronchial heart of octopus. (author)

The role of chemistry in the history of radioactivity (1897-1939)

International Nuclear Information System (INIS)

Adloff, J.P.

1997-01-01

Chemical research on radioactivity started in 1898. That year, Pierre and Marie Curie discovered in pitchblende polonium and radium. Rutherford and Soddy showed that radioactivity is an atomic phenomenon accompanied by transmutation of elements and established the basic laws of radioactive changes. The existence of isotopes was postulated after the discovery of many radioactive substances. Major discoveries in nuclear science, i.e. the atomic nucleus, the neutron and artificial radioactivity, were made with radiation sources elaborated bu chemists. Finally, in 1939, radiochemists on the search for transuranium elements, discovered nuclear fission. (authors)

Materials characterization of radioactive waste forms using a multi-element detection method based on the instrumental neutron activation analysis. MEDINA

International Nuclear Information System (INIS)

Havenith, Andreas Wilhelm

2015-01-01

Radioactive waste has to meet the specifications and acceptance criteria defined by national regulatory and management authorities for its intermediate and final storage. In Germany the Federal Office for Radiation Protection (Bundesamt fuer Strahlenschutz - BfS) has established waste acceptance requirements for the Konrad repository. Konrad is the disposal for radioactive waste with negligible heat generation and is located near the city of Salzgitter and is currently under construction. It will start operation not before the year 2021. The waste-acceptance-requirements are derived from a site-specific safety assessment. They include specific requirements on waste forms, packaging as well as limitations to activities of individual radionuclides and limitations to masses of non-radioactive harmful substances. The amount of chemically toxic elements in the waste is limited in order to avoid pollution of underground water reserves. To comply with these requirements every waste package has to be characterised in its radiological and chemical composition. This characterisation can be performed on the basis of existing documentation or, if the documentation is insufficient, on further analytical analysis. Segmented or integral gamma-scanning as well as active or passive neutron counting are used worldwide as the standard measurement methods for the radiological characterisation and quality checking of radioactive waste. These techniques determine the isotope specific activity of waste packages, but they do not allow the detection of non-radioactive hazardous substances inside the waste packages. Against this background the Institute of Nuclear Engineering and Technology Transfer (NET) at RWTH Aachen University and the Institute of Safety Research and Reactor Technology at Forschungszentrum Juelich jointly develop an innovative non-destructive analytical technique called MEDINA - ''Multi-Element Detection based on Instrumental Neutron Activation'' for

New radioactive tracers can help find cause of jaundice

International Nuclear Information System (INIS)

Carrard, G.

1987-01-01

Radioactive tracers for the investigation of a condition known as persistent jaundice of the newborn, have been designed, prepared and tested at ANSTO. The tracers are chemical compounds of the radioactive elements gallium-67 and indium-111. They given lower radiation doses than the conventional radioactive tracer, iodine-131, used in these studies

Chemical durability of glasses containing radioactive fission product waste

International Nuclear Information System (INIS)

Mendel, J.E.; Ross, W.A.

1974-04-01

Measurements made to determine the chemical durability of glasses for disposal of radioactive waste are discussed. The term glass covers materials varying from true glass with only minute quantities of crystallites, such as insoluble RuO 2 , to quasi glass-ceramics which are mostly crystalline. Chemical durability requirements and Soxhlet extractor leach tests are discussed

Origin of the chemical elements

Energy Technology Data Exchange (ETDEWEB)

Tayler, R J

1984-05-01

The subject is discussed in relation to the composition of initially created matter and changes which have occurred during the life history of the universe, with particular reference to our galaxy and nearby galaxies. Headings are: observations of element abundances (stars, gas clouds in our own and nearby galaxies, hot gas in galaxy clusters, the solar system); the originally created matter (Big Bang theory and early nuclear reactions); processes changing observed composition (galactic evolution; nuclear fusion reactions in stellar interiors; chemical composition of a highly evolved massive star); supernovae (production of heavy elements); chemical evolution of the galaxy; production of very heavy elements (s process, r process).

Chemical precipitation processes for the treatment of aqueous radioactive waste

International Nuclear Information System (INIS)

1992-01-01

Chemical precipitation by coagulation-flocculation and sedimentation has been commonly used for many years to treat liquid (aqueous) radioactive waste. This method allows the volume of waste to be substantially reduced for further treatment or conditioning and the bulk of the waste to de discharged. Chemical precipitation is usually applied in combination with other methods as part of a comprehensive waste management scheme. As with any other technology, chemical precipitation is constantly being improved to reduce cost to increase the effectiveness and safety on the entire waste management system. The purpose of this report is to review and update the information provided in Technical Reports Series No. 89, Chemical Treatment of Radioactive Wastes, published in 1968. In this report the chemical methods currently in use for the treatment of low and intermediate level aqueous radioactive wastes are described and illustrated. Comparisons are given of the advantages and limitations of the processes, and it is noted that good decontamination and volume reduction are not the only criteria according to which a particular process should be selected. Emphasis has been placed on the need to carefully characterize each waste stream, to examine fully the effect of segregation and the importance of looking at the entire operation and not just the treatment process when planning a liquid waste treatment facility. This general approach includes local requirements and possibilities, discharge authorization, management of the concentrates, ICRP recommendations and economics. It appears that chemical precipitation process and solid-liquid separation techniques will continue to be widely used in liquid radioactive waste treatment. Current research and development is showing that combining different processes in one treatment plant can provide higher decontamination factors and smaller secondary waste arisings. Some of these processes are already being incorporated into new and

Chemical engineering problems of radioactive waste fixation by vitrification

International Nuclear Information System (INIS)

Taylor, R.F.

1985-01-01

Basic features are reviewed of the chemical engineering problems faced in the vitrification of the high-level radioactive liquid wastes resulting from the reprocessing of nuclear fuel. After an outline of glass solution properties and formation kinetics the constituent elements of the vitrification route are examined in turn: waste feed evaporation and denitration, calcination, offgas treatment, and finally melting and product quality. Plant and experimental data for each stage are discussed with comparison between process routes and with reference to the underlying principles. Attention is drawn to the future need for higher trapping efficiencies and for dealing with a wider range of species in offgas treatments as higher burnup fuels are processed after shorter cooling times from reactor. Two areas of present study where deeper insight into underlying process mechanics is needed are, firstly, the association of waste material with glass formers in the wet or sinter stages and secondly their incorporation and mixing reaction in the melt. Fuller understanding here would bring direct benefit to process performance and handling. The problems discussed are not of a nature to jeopardize the vitrification routes but if product quality does come to rely heavily on process control then demonstrable confidence in the behaviour of the central physico-chemical interactions is indispensable. (author)

Trace elements and radioactivity in aerosol particles, produced in the area of Ptolemais (Greece)

International Nuclear Information System (INIS)

Kallithrakas-Kontos, N.; Zoumi, K.; Nikolakaki, S.; Kritidis, P.

1998-01-01

Most of the Greek lignite power plants have been installed in the area of Ptolemais, and a major part of them during the period 1981-1990. Aerosol filters collected in the first and the last years of the decade have been analysed for trace elements as well as for radioactivity (total beta) content. Analysis was performed by radioisotope excited X-ray fluorescence, and 17 elements were determined. A special interest is focused on lead concentrations, an element whose environmental concentrations are regulated by the Greek law; the results for lead were validated by atomic absorption spectrometry. Trace element and radioactivity levels were found significantly lower than the current limit. Enrichment factors and correlation among the analysed elements were also estimated. (author)

Dissolved Concentration Limits of Radioactive Elements

Energy Technology Data Exchange (ETDEWEB)

Y. Chen; E.R. Thomas; F.J. Pearson; P.L. Cloke; T.L. Steinborn; P.V. Brady

2003-06-20

The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of radioactive elements under possible repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, and measurements made in laboratory experiments and field work. The scope of this modeling activity is to predict dissolved concentrations or solubility limits for 14 radioactive elements (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium), which are important to calculated dose. Model outputs are mainly in the form of look-up tables plus one or more uncertainty terms. The rest are either in the form of distributions or single values. The results of this analysis are fundamental inputs for total system performance assessment to constrain the release of these elements from waste packages and the engineered barrier system. Solubilities of plutonium, neptunium, uranium, americium, actinium, thorium, protactinium, lead, and radium have been re-evaluated using the newly updated thermodynamic database (Data0.ymp.R2). For all of the actinides, identical modeling approaches and consistent environmental conditions were used to develop solubility models in this revision. These models cover broad ranges of environmental conditions so that they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, activity coefficients, and selection of solubility controlling phase have been quantified or otherwise addressed. Moreover, a new blended plutonium solubility model has been developed in this revision, which gives a mean solubility that is three orders of magnitude lower than the plutonium solubility model used for the Total System Performance Assessment for the Site Recommendation. Two alternative neptunium solubility models have also been

Dissolved Concentration Limits of Radioactive Elements

International Nuclear Information System (INIS)

Y. Chen; E.R. Thomas; F.J. Pearson; P.L. Cloke; T.L. Steinborn; P.V. Brady

2003-01-01

The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of radioactive elements under possible repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, and measurements made in laboratory experiments and field work. The scope of this modeling activity is to predict dissolved concentrations or solubility limits for 14 radioactive elements (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium), which are important to calculated dose. Model outputs are mainly in the form of look-up tables plus one or more uncertainty terms. The rest are either in the form of distributions or single values. The results of this analysis are fundamental inputs for total system performance assessment to constrain the release of these elements from waste packages and the engineered barrier system. Solubilities of plutonium, neptunium, uranium, americium, actinium, thorium, protactinium, lead, and radium have been re-evaluated using the newly updated thermodynamic database (Data0.ymp.R2). For all of the actinides, identical modeling approaches and consistent environmental conditions were used to develop solubility models in this revision. These models cover broad ranges of environmental conditions so that they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, activity coefficients, and selection of solubility controlling phase have been quantified or otherwise addressed. Moreover, a new blended plutonium solubility model has been developed in this revision, which gives a mean solubility that is three orders of magnitude lower than the plutonium solubility model used for the Total System Performance Assessment for the Site Recommendation. Two alternative neptunium solubility models have also been

Improvement of the safety regulations in the management of radioactive waste accumulated in the liquid radioactive waste water basins of the PO 'Majak' (Ozersk), the Siberian Chemical Plant (Seversk) and the Mining-Chemical Plant (Zheleznogorsk)

International Nuclear Information System (INIS)

Vishnevski, Y.G.; Kislov, A.I.; Irushkin, V.M.

2002-01-01

One of the most important problems of radiation safety in Russia is the decommissioning of the liquid radioactive waste water basins of the PO 'Majak' (Ozersk), Siberian Chemical Plant (Seversk) and Mining-Chemical Plant (Zheleznogorsk). The liquid radioactive waste water basins were constructed in 1950-1960 for the collection and storage of liquid waste from the radiochemical plants. The potential hazards of the liquid in the radioactive waste water basins are: migration of radionuclides into the soil of the liquid radioactive waste water basin floors; wind-induced carry-over of radionuclides from the liquid radioactive waste water basins; hazards (radiation included) to the environment and population arising in case physical barriers and hydraulic structures are damaged; and criticality hazards. The classification of the liquid radioactive waste water basins were developed based on the collection and analyzes of the information on liquid radioactive waste water basin characteristics and the method of multicriterion expert assessment of potential hazards. Three main directions for the improvement of safety regulation in the management of radioactive waste accumulated in the liquid radioactive waste water basins were defined: 1. Common directions for the improvement of safety regulation in the area of rehabilitation of the territories contaminated with radioactive substances. 2. Common directions for the improvement of safety regulation in the area of rehabilitation of the territories, such as the liquid radioactive waste water basins. 3. Special directions for the regulatory activities in the area of operation and decommissioning of the liquid radioactive waste water basins of the PO 'Majak' (Ozersk), Siberian Chemical Plant (Seversk) and Mining-Chemical Plant (Zheleznogorsk). As a result, concrete recommendations on safety regulation for the management of radioactive waste accumulated in the water basins were developed. (author)

Applicability of thermodynamic database of radioactive elements developed for the Japanese performance assessment of HLW repository

International Nuclear Information System (INIS)

Yui, Mikazu; Shibata, Masahiro; Rai, Dhanpat; Ochs, Michael

2003-01-01

In 1999 Japan Nuclear Cycle Development Institute (JNC) published a second progress report (also known as H12 report) on high-level radioactive waste (HLW) disposal in Japan (JNC 1999). This report helped to develop confidence in the selected HLW disposal system and to establish the implementation body in 2000 for the disposal of HLW. JNC developed an in-house thermodynamic database for radioactive elements for performance analysis of the engineered barrier system (EBS) and the geosphere for H12 report. This paper briefly presents the status of the JNC's thermodynamic database and its applicability to perform realistic analyses of the solubilities of radioactive elements, evolution of solubility-limiting solid phases, predictions of the redox state of Pu in the neutral pH range under reducing conditions, and to estimate solubilities of radioactive elements in cementitious conditions. (author)

Naturally occurring radioactive elements, arsenic and other metals in drinking water from private wells

International Nuclear Information System (INIS)

Ek, Britt-Marie; Thunholm, Bo; Oestergren, Inger; Falk, Rolf; Mjoenes, Lars

2008-04-01

island of Gotland, where the bedrock is dominated by Silurian limestones, the majority of the water samples showed boron concentrations far exceeding the provisional guide line value 500 μg/l set by WHO. Metals like lead, cadmium, nickel and chromium are only rarely found in harmful concentrations in Swedish drinking-water. A conclusion of the results from this study is that ordinary analyses of physico-chemical and microbiological parameters as well as radon-222, should be complemented with analyses of metals including uranium and arsenic, especially in waters from drilled wells in bedrock. A direct finding from this study is that radium-226 accumulates in some types of common water filters, which are often used to decrease iron and manganese. With arsenic concentrations in the drinking water exceeding the guide line 10 μg/l, actions should be taken to reduce the concentrations below this limit. Recent tests by the National Board of Health and Welfare of Sweden have shown that adsorption and ion exchange can reduce arsenic in drinking water up to 98 %. This project has shown that arsenic accumulates to a large degree in common water filters installed to remove iron and manganese. This study gives an overview of how drinking water, extracted from private wells, is influenced by various elements that occur naturally in our environment. New problem areas such as a radiation dose from lead-210 and polonium-210 have been identified. Information campaigns addressing different target groups, like county councils and municipalities, are necessary to inform well owners about the issues on radon, uranium, arsenic, fluoride and water filters. Additional studies are needed to further increase our knowledge on radioactive elements, arsenic and other possibly harmful elements in drinking water. A further mapping of lead-210 and polonium-210 occurrence in drinking water would allow for better estimates of dose to the public

Canister arrangement for storing radioactive waste

Science.gov (United States)

Lorenzo, D.K.; Van Cleve, J.E. Jr.

1980-04-23

The subject invention relates to a canister arrangement for jointly storing high level radioactive chemical waste and metallic waste resulting from the reprocessing of nuclear reactor fuel elements. A cylindrical steel canister is provided with an elongated centrally disposed billet of the metallic waste and the chemical waste in vitreous form is disposed in the annulus surrounding the billet.

Fuel element replacement and cooling water radioactivity at the Musashi reactor

International Nuclear Information System (INIS)

Nozaki, T.; Honda, T.; Horiuchi, N.; Aizawa, O.; Sato, T.

1988-01-01

The Musashi reactor (TRIGA-II, 100kW) has been operated without any serious troubles since 1963. In 1985 the old Al-cladded fuel elements were replaced with new stainless cladded ones in order to insure a long and safe operation. By using a semi-automatic equipment the old fuel elements have been transferred into the bulk-shielding experimental pool, which was remodelled for the spent-fuel storage. In order to reduce the exposure during the transfer work, the old fuel elements were cooled in the core tank for 3 months. After the replacement, the radioactivities in the cooling water have been drastically changed. The activity of Na-24 decreased about one decade, and the activities of Cr-51, Mn-54, Mn-56, Co-58 and Co-60 increased about two decades. At this conference we will report on the following points: (1) semi-automatic equipment for the transportation of the Al-cladded spent fuel, (2) structure of spent-fuel storage pool, and (3) radioactivity change in the cooling water. (author)

Biological effects of concomitant influence of radioactive and chemical factors. (Experimental research)

International Nuclear Information System (INIS)

Meshkov, N.A.

1995-01-01

Remote consequences of concomitant influence of radioactive and chemical hazards substances, modeling the ecological situation at the territory of the Altaj region after the nuclear tests at the Semipalatinsk test site is studied on the mice. Negative effect of the concomitant impact of radioactive and hazardous chemical substances on the basic morpho-functional systems of animals is revealed; the reproduction function proved to be the most sensitive one. It is noted that the radiation factor constitutes the basis of all violations of bone marrow blood-producing function by concomitant influence

The origin of the chemical elements

International Nuclear Information System (INIS)

Tayler, R.J.

1984-01-01

The subject is discussed in relation to the composition of initially created matter and changes which have occurred during the life history of the universe, with particular reference to our galaxy and nearby galaxies. Headings are: observations of element abundances (stars, gas clouds in our own and nearby galaxies, hot gas in galaxy clusters, the solar system); the originally created matter (Big Bang theory and early nuclear reactions); processes changing observed composition (galactic evolution; nuclear fusion reactions in stellar interiors; chemical composition of a highly evolved massive star); supernovae (production of heavy elements); chemical evolution of the galaxy; production of very heavy elements (s process, r process). (U.K.)

Program for responsible and safe disposal of spent fuel elements and radioactive wastes (National disposal program)

International Nuclear Information System (INIS)

2015-01-01

The contribution covers the following topics: fundamentals of the disposal policy; amount of radioactive wastes and prognosis; disposal of radioactive wastes - spent fuel elements and wastes from waste processing, radioactive wastes with low heat production; legal framework of the nuclear waste disposal in Germany; public participation, cost and financing.

The radioactive earth

International Nuclear Information System (INIS)

Plant, J.A.; Saunders, A.D.

1996-01-01

Uranium, thorium and potassium are the main elements contributing to natural terrestrial radioactivity. The isotopes 238 U, 235 U, 232 Th and 40 K decay with half-lives so long that significant amounts remain in the earth, providing a continuing source of heat. The slow decay of these isotopes also provides the basis for radiometric age dating and isotopic modelling of the evolution of the earth and its crust. There is a complex interplay between their heat production and the processes involved in crust formation. Phenomena such as volcanism, earthquakes, and large-scale hydrothermal activity associated with ore deposition reflect the dissipation of heat energy from the earth, much of which is derived from natural radioactivity. The higher levels of radioactive elements during the early history of the earth resulted in higher heat flow. All three of the radioactive elements are strongly partitioned into the continental crust, but within the crust their distribution is determined by their different chemical properties. The behaviour of U, which has two commonly occurring oxidation states, is more complex than that of Th and K. Uranium deposits are diverse, and are mostly associated with granites, acid volcanics, or detrital sedimentary rocks. The most important U deposits economically are unconformity-type ores of Proterozoic age, in which U is enriched by up to 5 x 10 6 with respect to bulk earth values. In some cases natural radioactivity can be of environmental concern. The most significant risk is posed by accumulations of radon, the gaseous daughter product of U. (author)

Group theoretical classification of chemical elements

International Nuclear Information System (INIS)

Byakov, V.M.; Kulakov, V.I.; Rumer, Y.B.; Fet, A.L.

1977-01-01

The method of classification of chemical elements, based on group symmetry principles, is compared with element properties. Elements are considered to be states of a single quantum system, the atomic structure being ignored. Elements treated as states of the system, break down into successively diminishing subsystems, big and small multiplets. The theory, being a group classification, does not describe in detail any of element properties, but leads to a unified qualitative description of all of them simultaneously

Advances in chemical investigations of the heaviest elements

Directory of Open Access Journals (Sweden)

Türler Andreas

2016-01-01

Full Text Available Although somewhat in the shadow of the discoveries of new elements, experimental chemical investigations of the heaviest elements have made tremendous progress in the last decades. Indeed, it was possible to experimentally determine thermochemical properties of heavy transactinide elements such as copernicium or flerovium. But will it be possible to chemically study all currently known elements of the periodic table up to element 118? While it is experimentally feasible to work with single atoms, the short half-lives of even the longest currently known isotopes of elements 115 through 118 call for new experimental approaches.

Three Packets of Minerals of the Periodic Table of Chemical Elements and Chemical Compounds

OpenAIRE

Labushev, Mikhail M.

2013-01-01

The concepts of alpha- and beta-packets of the periodic table of chemical elements and chemical compounds are defined. The first of the 47 minerals alpha-packets is composed. In it all minerals are arranged in increasing Iav index of proportionality of atomic weights of composing chemical elements, the same way as chemical elements are located in increasing atomic weights in the Periodic table. The packet includes 93 known minerals and two compounds - N2O5 and CO2 - being actually minerals. B...

Distribution of natural radioactive elements in Western Carpathians granitoids

International Nuclear Information System (INIS)

Katlovsky, V.

1979-01-01

The content of natural radioactive elements was determined using the 1024-channel analyser NTA-512 B with NaI(Tl) scintillators or with a Ge(Li) detector. The following groups of samples were processed: 1. granitoids, pegmatites and weathered rocks in the Small Carpathians; 2. acid magmatites of exotic rocks of the klippen zone; 3. granitoids of the Western Carpathians. The results of the measurements are summed up. (Ha)

Lipid spectrum of the newborn rats' blood at the radioactive and chemical effects in the prenatal period

International Nuclear Information System (INIS)

Buzan, Kh.

1998-01-01

The radioactive and chemical factors used in complex or separately during the prenatal period in the experiment induce ambiguous effects on the lipid metabolism in blood plasma and erythrocytes of newborn rats. The chemicals cause more significant changes in the blood plasma lipid metabolism than the radioactive irradiation does. Being used combined the radioactive and chemical factors do not increase each other's effect- their effects have opposite directions. The radiochemical exposure induce more significant shifts in the lipid spectrum in erythrocytic membranes than the separate factors

Chemical elements in Leucaena leucocephala leaves of riparian zones of the municipality of Piracicaba, São Paulo, Brazil

International Nuclear Information System (INIS)

França, Elvis J. de; Fernandes, Elisabete A.N.; Lira, Marcelo G.; Ferreira, Fabiano S.; Cavalca, Isabel P.O.; Rodrigues, Vanessa S.; Camilli, Leandro

2017-01-01

The species Leucaena leucocephala can be found in several riparian ecosystems, acting as one of the main invasive and harmful species for the forest restoration of the permanent preservation areas. It has also been studied for the phytoremediation of some chemical elements, due to their potential accumulation of chemical substances. Therefore, the present study aimed to evaluate the accumulation of chemical elements in leaves of Leucaena leucocephala trees by Instrumental Neutronic Activation Analysis - INAA. Samples of leaves were collected in eight samples from riverside areas of the Piracicaba Municipality, São Paulo, Brazil, during the dry and rainy season. After collection, washing with water and drying in a forced circulation oven, the samples were comminuted and encapsulated in polyethylene capsules and subjected to a thermal neutron flux of 10 13 cm -2 s -1 for 8 hours in the Nuclear Research Reactor IEA-R1 of IPEN / CNEN. Thermal neutron flux monitoring was performed by Ni-Cr alloy fragments with known concentrations of the chemical monitors elements. After measurements of radioactivity induced by HPGe detectors, the concentrations of the chemical elements were calculated by the k0 method using the Quantu computer program. Certified reference materials were also analyzed for quality assurance of the analytical procedure. The results indicated high concentrations of La and lanthanoids (Ce, Eu, Sm, Tb and Yb) in leaves of L. leucocephala in both periods analyzed. It was possible to observe a decrease in the concentrations of the chemical elements in the rainy season, probably associated to the washing of the geological material deposited on the leaves of the trees by the rains, except for K, Mo, Rb, Sb and Zn, whose values remained or increased in the leaves collected during the rainy season. Considering the constant leaf production, L. leucocephala can greatly affect the cycling of chemical elements due to its accumulation capacity demonstrated by this

Final report on fabrication and study of SYNROC containing radioactive waste elements

International Nuclear Information System (INIS)

Reeve, K.D.; Levins, D.M.; Seatonberry, B.W.; Ryan, R.K.; Hart, K.P.; Stevens, G.T.

1987-01-01

Two facilities for the fabrication and testing of Synroc samples containing separate additions of the transuranic actinides americium, plutonium, curium and neptunium, a fission product solution, and two radioisotopes of caesium and strontium were designed, built and operated by the AAEC at the Lucas Heights Research Laboratories. Twenty-one 75 g batches of radioactive Synroc were made and representative samples were characterised by alpha track etching, scanning electron microscopy and aqueous leach testing, mostly at 70 deg C. Where comparisons were possible, radioactive fission products behaved as expected from non-radioactive tests. The leaching behaviour of the actinides was complex but as a group they were the least leachable of all the elements studied

Release of radioactive fission products from BN-600 reactor untight fuel elements

International Nuclear Information System (INIS)

Osipov, S.L.; Tsikunov, A.G.; Lisitsin, E.C.

1996-01-01

The experimental data on the release of radioactive fission products from BN-600 reactor untight fuel elements are given in the report. Various groups of radionuclides: inert gases Xe, Kr, volatile Cs, J, non-volatile Nb, and La are considered. The results of calculation-experimental study of transfer and distribution of radionuclides in the reactor primary circuit, gas system and sodium coolant are considered. It is shown that some complex radioactivity transfer processes can be described by simple mathematical models. (author)

Radioactivity in the environment

International Nuclear Information System (INIS)

Costello, J.M.

1983-01-01

Radioactivity is a natural phenomenon. Out of 1700 known isotopes of 104 chemical elements, only about 16 per cent are stable. Seventy-three radioactive isotopes of 39 elements occur naturally in the terrestrial environment. The significance of environmental radioactivity lies in the contribution to the annual exposure of the general population to ionising radiation. This exposure results largely from natural sources of radioactivity and radiation together with applications of radiation in medicine. Minor contributions are from nuclear weapons tests, nuclear power production and the nuclear fuel cycle, and consumer products including luminous clocks and watches, television receivers and smoke detectors. The natural background radiation level varies substantially with altitude and geographic location. Although no satisfactory evidence is available that natural variations in background radiation levels are detrimental to humans, upper limits of risk have been estimated for possible somatic and genetic effects from these levels of radiation. Contributory sources of and variability in the radiation background are reviewed and the relation between effective dose equivalent and associated detriment outlined. The risk from exposure to an average level of background radiation is compared with risks from other human activities

Studies on radioactivity distribution and radioactive mineral identification in uranium ores from Espinharas (PB), Brazil

International Nuclear Information System (INIS)

Oliveira, G.N.M. de.

1979-01-01

Studies about the identification of radioactive minerals in uranium bearing rocks from Espinharas (PB), Brazil are presented. Autoradiography with α-sensitive nuclear emulsions was utilized for determining radioctivity distributions and for localizing radioactive minerals, in combination with microscopy, X-ray diffractometry, PIXE and eletron microprobe analysis for its identification. Mineralized gneisse and feldspatic rock, the two principal samples studied, show distinct differences in radioactive distribution patterns, however the main carriers for U and Th seem to be the same. Microanalysis shows that elements are associated with Si, Ca, Fe and Al an some trace elements like Y, Zr, Ti, etc. U and Th are distributed uniformly in feldspatic rock and inhomogeneously in mineralized gneisse, indicating that the zonary structure of the radioactive cristals, frequently observed in gneisse, could be due to variable U:Th ratios. Chemical analysis, X-ray diffraction datas and microscopic studies indicates that the principal carrier for radioactivity in the rocks of Espinharas is a silicate mineral of U and Th, probably situaded in the series of transition: Coffinite -> uraninite, thorogummite -> thorianite. Some additional experiments about leachability of uranium with diluted sulfuric acid are reported, which confirm the different nature of radioactivity distribution in feldspatic and gneissic rocks. (author) [pt

Changes is radioactive iodine metabolism in acute chemical intoxications

International Nuclear Information System (INIS)

Selyutitskij, G.V.; Likhtarev, I.A.; Volkova, N.V.; Zvonova, I.A.; Ostryakova, N.I.

1978-01-01

It is shown that the response of the endocrine system (iodine-absorbing and hormone-secreting fUnctions of the thyroid) as studied by the radioactive iodine test may be a reasonably versatile indicator of the response of the thyroid component of the endocrine system to acute intoxication of the organism. Trials of this test using seven chemical substances have confirmed that the radioiodine test is a sufficienty universal method to be used in setting sanitary and hygienic standards for permissible levels of chemical substances

Measurements of radon and chemical elements: Popocatepetl volcano

International Nuclear Information System (INIS)

Pena, P.; Segovia, N.; Lopez, B.; Reyes, A.V.; Armienta, M.A.; Valdes, C.; Mena, M.; Seidel, J.L.; Monnin, M.

2002-01-01

The Popocatepetl volcano is a higher risk volcano located at 60 Km from Mexico City. Radon measurements on soil in two fixed seasons located in the north slope of volcano were carried out. Moreover the radon content, major chemical elements and tracks in water samples of three springs was studied. The radon of soil was determined with solid detectors of nuclear tracks (DSTN). The radon in subterranean water was evaluated through the liquid scintillation method and it was corroborated with an Alpha Guard equipment. The major chemical elements were determined with conventional chemical methods and the track elements were measured using an Icp-Ms equipment. The radon on soil levels were lower, indicating a moderate diffusion of the gas across the slope of the volcano. The radon in subterranean water shown few changes in relation with the active scene of the volcano. The major chemical elements and tracks showed a stable behavior during the sampling period. (Author)

Physical and chemical investigation of water and sediment of the Keban Dam Lake, Turkey. Part 2. Distribution of radioactivity, heavy metals and major elements

International Nuclear Information System (INIS)

Kulahci, F.; Dogru, M.

2006-01-01

Thirtynine surface water and 20 deep sediment samples were taken in different locations in Keban Dam Lake (Elazig, Turkey) to identify major sources and assess major elements, heavy metals, 137 Cs, 90 Sr, total alpha- and, total beta-distribution in 2003 and 2004 in four seasons each year. As a preliminary study heavy metal (Zn, Fe, Mn, Ni, Cu, Cr, and Co), major element (Mg, Ca, Na, K) and radioactivity concentrations of 137 Cs, 90 Sr, total-α and total-β in the surface water and deep sediments were determined. (author)

Radiological and related Chemical Health Impact Assessments of ...

African Journals Online (AJOL)

Ogunjo Samuel

concentrations obtained and the relation from United State Environmental Protection Agency (USEPA), the chemical ... radioactive elements uranium-238 and thorium-232 decay .... Using Equation 2, the elemental concentrations in pipe.

Study of chemical reactions in the nuclear underground explosion - Incidence on radioactivity

International Nuclear Information System (INIS)

Picq, Jean Maurice

1970-01-01

In order to find out and state the theoretical or semi-empirical laws governing the reaction of radioactivity in contained nuclear explosion, we are studying the chemical reactions during the different stages of the cavity and chimney formation, as well as thermal transfers. At the same time, we are carrying an experimental study on melted rock and gas samples taken from the French underground explosions. The results of which can be found in this paper are derived from our present experiments at the plant (have been obtained from partial studies). During the French underground explosions, we took gaseous samples. The gas analysis, without taking water vapour into consideration, showed that those samples were composed of hydrogen, carbon dioxide, carbon monoxide with small quantities of hydrocarbons (chiefly methane - about one per cent). The total amount of gas being quite large and proportional to the burst power, we came to the conclusion that those gases were produced by rock reactions (that rock was granite). We considered the following reagents because they were found in sufficient quantities to alter the balance between the different components: ferrous ions contained in mica, biotite, carbon dioxide from carbonates and water, either free or in a component state, contained in the rock. A comparison between theoretical and experimental results led us to notice among other things: the temperature of rock re-solidification; pressure nearing lithostatic pressure. Since the components of the environment, water not included, is quite homogeneous, the gas volume produced by '1 kiloton' is quite constant. On the other hand, the relative proportion of the gases undergoes a few changes, particularly the ratio CO/CO 2 which normally depends on the quantity of water contained in the environment. This statement is verified by the calculation of thermodynamic equilibriums. In order to calculate the simultaneous chemical equilibrium we have first selected five reactions. We

Characterization of chemical elements of fruits of Leucaena leucocephala in riverside areas of the Piracicaba River Basin, São Paulo, Brazil

International Nuclear Information System (INIS)

França, Elvis J.; Magalhães, Marcelo R.L. de; Ferreira, Fabiano S.; Fernandes, Elisabete A. de N.; Fonseca, Felipe Y.; Rodrigues, Vanessa S.; Cavalca, Isabel P.O.; Camilli, Leandro; Silva, Bruno F.

2017-01-01

The species Leucaena leucocephala is present in several environments. Its fruit is widely used in cattle feed. However, it is classified as an invasive species, causing problems in the restoration of impacted areas. The Piracicaba River Basin is heavily affected by urbanization and industrialization, which shows the proliferation of this species. Considering the importance of this tree species for Brazil, the present study quantifies chemical elements in fruits of this species by applying Instrumental Neutronic Activation Analysis, method k 0 . Samples were collected in riverside areas of the Piracicaba Municipality, São Paulo, Brazil, at different periods (dry and rainy season). After collection, the samples were shattered and transferred to polyethylene capsules and irradiated with neutrons. Certified reference materials were used to evaluate the quality of the analytical procedure, all material was irradiated under a thermal neutron flux of 10 13 cm-2s-1 for 8 hours. Ni-Cr alloy was used for the monitoring of thermal neutron flux. High Resolution Range Spectrometry with HPG detectors was employed for the measurement of the induced radioactivity, allowing the quantification of the chemical elements. Compared with available results of chemical analysis of pods, the chemical elements Ca, K, Ba, Cr and Se presented high concentrations. We also quantified chemical elements of environmental relevance such as As, Hg, Br, Ce, Cs, Eu, Hf, La, Rb, Sb, Sc, Sm, Ta, Tb, Th and Yb, indicating the need for element dynamics studies in the environments occupied by this invasive species

Using proven, cost-effective chemical stabilization to remediate radioactive and heavy metal contaminated sites

International Nuclear Information System (INIS)

Jensen, R.; Sogue, A.

1999-01-01

Rocky Mountain Remediation Services, L.L.C. (RMRS) has deployed a cost-effective metals stabilization method which can be used to reduce the cost of remediation projects where radioactivity and heavy metals are the contaminants of concern. The Envirobond TM process employs the use of a proprietary chemical process to stabilize metals in many waste forms, and provides an excellent binding system that can easily be compacted to reduce the waste into a shippable brick called Envirobric TM . The advantages of using chemical stabilization are: (1) Low cost, due to the simplicity of the process design and inexpensive reagents. (2) Chemical stabilization is easily deployed in field applications, which limit the amount of shielding and other protective measures. (3) The process does not add volume and bulk to the treated waste; after treatment the materials may be able to remain on-site, or if transportation and disposal is required the cost will be reduced due to lower volumes. (4) No secondary waste. The simplicity of this process creates a safe environment while treating the residues, and the long-term effectiveness of this type of chemical stabilization lowers the risk of future release of hazardous elements associated with the residues. (author)

Processing method for liquid waste containing various kinds of radioactive material

International Nuclear Information System (INIS)

Toyabe, Keiji; Nabeshima, Masahiro; Ozeki, Noboru; Muraki, Tsutomu.

1996-01-01

Various kind of radioactive materials and heavy metal elements dissolved in liquid wastes are removed from the liquid wastes by adsorbing them on chitin or chitosan. In this case, a hydrogen ion concentration in the liquid wastes is adjusted to a pH value of from 1 to 3 depending on the kinds of the radioactive materials and heavy metal elements to be removed. Since chitin or chitosan has a special ion exchange performance or adsorbing performance, chemical species comprising radioactive materials or heavy metals dissolved in the liquid wastes are adsorbed thereto by ion adsorption or physical adsorption. With such procedures, radioactive materials and heavy metal elements are removed from the liquid wastes, and the concentration thereof can be reduced to such a level that they can be discharged into environments. On the other hand, since chitin or chitosan adsorbing the radioactive materials and heavy metal elements has a structure of polysaccharides, it is easily burnt into gaseous carbon dioxide. Accordingly, the amount of secondary wastes can remarkably be reduced. (T.M.)

Exploring the Everyday Context of Chemical Elements: Discovering the Elements of Car Components

Science.gov (United States)

Franco-Mariscal, Antonio Joaquín

2015-01-01

This paper presents a project about the chemical elements made by 15-year-old Spanish high school students of Chemistry. It focuses on context-based teaching combined with the advantages of creating a large mural which subsequently is exposed in the school. The project consisted of researching the chemical elements in the different materials that…

Materials characterization of radioactive waste forms using a multi-element detection method based on the instrumental neutron activation analysis. MEDINA; Stoffliche Charakterisierung radioaktiver Abfallprodukte durch ein Multi-Element-Analyseverfahren basierend auf der instrumentellen Neutronen-Aktivierungs-Analyse. MEDINA

Energy Technology Data Exchange (ETDEWEB)

Havenith, Andreas Wilhelm

2015-07-01

Radioactive waste has to meet the specifications and acceptance criteria defined by national regulatory and management authorities for its intermediate and final storage. In Germany the Federal Office for Radiation Protection (Bundesamt fuer Strahlenschutz - BfS) has established waste acceptance requirements for the Konrad repository. Konrad is the disposal for radioactive waste with negligible heat generation and is located near the city of Salzgitter and is currently under construction. It will start operation not before the year 2021. The waste-acceptance-requirements are derived from a site-specific safety assessment. They include specific requirements on waste forms, packaging as well as limitations to activities of individual radionuclides and limitations to masses of non-radioactive harmful substances. The amount of chemically toxic elements in the waste is limited in order to avoid pollution of underground water reserves. To comply with these requirements every waste package has to be characterised in its radiological and chemical composition. This characterisation can be performed on the basis of existing documentation or, if the documentation is insufficient, on further analytical analysis. Segmented or integral gamma-scanning as well as active or passive neutron counting are used worldwide as the standard measurement methods for the radiological characterisation and quality checking of radioactive waste. These techniques determine the isotope specific activity of waste packages, but they do not allow the detection of non-radioactive hazardous substances inside the waste packages. Against this background the Institute of Nuclear Engineering and Technology Transfer (NET) at RWTH Aachen University and the Institute of Safety Research and Reactor Technology at Forschungszentrum Juelich jointly develop an innovative non-destructive analytical technique called MEDINA - ''Multi-Element Detection based on Instrumental Neutron Activation'' for

Chemical element abundance in K giant atmospheres

International Nuclear Information System (INIS)

Komarov, N.S.; Shcherbak, A.N.

1980-01-01

With the help of modified method of differential curves of growth studied are physical parameters of atmospheres of giant stars of KO111 spectral class of the NGC 752, M25 and UMa cluster. Observations have been made on reflector of Crimea astrophysical observatory of Academy of Sciences of the USSR in the period from February to May, 1978. Spectograms are obtained for the wave length range from 5000-5500 A. It is shown that the change of chemical content in the wide range in heavy element composition does not influence the star atmosphere structUre. It follows from the results of the investigation that the abundance of chemical elements in stars of various scattered clusters, is the same in the range of errors of measurements and is similar to the abundance of chemical elements in the Sun atmosphere

Plants' essential chemical elements

Science.gov (United States)

Kevin T. Smith

2007-01-01

Every garden center and hardware store sells fertilizer guaranteed to "feed" plants. In a strict sense, we can't feed plants. Food contains an energy source. Green plants capture solar energy and make their own food through photosynthesis! Photosynthesis and other metabolic processes require chemical elements in appropriate doses for plants to survive...

Prompt gamma neutron activation analysis of toxic elements in radioactive waste packages

Energy Technology Data Exchange (ETDEWEB)

Ma, J.-L. [CEA, DEN, Cadarache, Nuclear Measurement Laboratory, F-13108 St Paul-lez-Durance (France); Carasco, C., E-mail: cedric.carasco@cea.fr [CEA, DEN, Cadarache, Nuclear Measurement Laboratory, F-13108 St Paul-lez-Durance (France); Perot, B. [CEA, DEN, Cadarache, Nuclear Measurement Laboratory, F-13108 St Paul-lez-Durance (France); Mauerhofer, E.; Kettler, J.; Havenith, A. [Institute of Energy and Climate Research - Nuclear Waste Management and Reactor Safety, Forschungszentrum Juelich GmbH (Germany)

2012-07-15

The French Alternative Energies and Atomic Energy Commission (CEA) and National Radioactive Waste Management Agency (ANDRA) are conducting an R and D program to improve the characterization of long-lived and medium activity (LL-MA) radioactive waste packages. In particular, the amount of toxic elements present in radioactive waste packages must be assessed before they can be accepted in repository facilities in order to avoid pollution of underground water reserves. To this aim, the Nuclear Measurement Laboratory of CEA-Cadarache has started to study the performances of Prompt Gamma Neutron Activation Analysis (PGNAA) for elements showing large capture cross sections such as mercury, cadmium, boron, and chromium. This paper reports a comparison between Monte Carlo calculations performed with the MCNPX computer code using the ENDF/B-VII.0 library and experimental gamma rays measured in the REGAIN PGNAA cell with small samples of nickel, lead, cadmium, arsenic, antimony, chromium, magnesium, zinc, boron, and lithium to verify the validity of a numerical model and gamma-ray production data. The measurement of a {approx}20 kg test sample of concrete containing toxic elements has also been performed, in collaboration with Forschungszentrum Juelich, to validate the model in view of future performance studies for dense and large LL-MA waste packages. - Highlights: Black-Right-Pointing-Pointer Comparison between measurements and MCNP calculation has been performed for a PGNAA system. Black-Right-Pointing-Pointer The system aims at controlling the amount of toxic elements in nuclear waste. Black-Right-Pointing-Pointer Simple samples and a concrete cylinder in which impurities have been added are used. Black-Right-Pointing-Pointer Calculations agree within a factor 2 with measurements. Black-Right-Pointing-Pointer The system can be improved with a better neutron flux monitoring and the use of boron-free graphite.

Rapid immobilization of simulated radioactive soil waste by microwave sintering.

Science.gov (United States)

Zhang, Shuai; Shu, Xiaoyan; Chen, Shunzhang; Yang, Huimin; Hou, Chenxi; Mao, Xueli; Chi, Fangting; Song, Mianxin; Lu, Xirui

2017-09-05

A rapid and efficient method is particularly necessary in the timely disposal of seriously radioactive contaminated soil. In this paper, a series of simulated radioactive soil waste containing different contents of neodymium oxide (3-25wt.%) has been successfully vitrified by microwave sintering at 1300°C for 30min. The microstructures, morphology, element distribution, density and chemical durability of as obtained vitrified forms have been analyzed. The results show that the amorphous structure, homogeneous element distribution, and regular density improvement are well kept, except slight cracks emerge on the magnified surface for the 25wt.% Nd 2 O 3 -containing sample. Moreover, all the vitrified forms exhibit excellent chemical durability, and the leaching rates of Nd are kept as ∼10 -4 -10 -6 g/(m 2 day) within 42days. This demonstrates a potential application of microwave sintering in radioactive contaminated soil disposal. Copyright © 2017 Elsevier B.V. All rights reserved.

Accelerator Driven Sub-Critical System for the Radioactive Waste Transmutation

International Nuclear Information System (INIS)

Avramovic, I.; Pesic, M.

2008-01-01

Spent nuclear fuel discharged from nuclear power plants is the main problem during design of radioactive waste disposal. Most of the hazard stems from only a few chemical elements. The radiotoxicity of these elements can be efficiently reduced using partitioning and transmutation in fast reactors and accelerator driven subcritical systems. (author)

HISTORY OF THE ORIGIN OF THE CHEMICAL ELEMENTS AND THEIR DISCOVERIES

International Nuclear Information System (INIS)

HOLDEN, N.E.

2001-01-01

The origin of the chemical elements show a wide diversity with some of these elements having their origin in antiquity. Still other elements have been synthesized within the past fifty years via nuclear reactions on heavy elements, because these other elements are unstable and radioactive and do not exist in nature. The names of the elements come from many sources including mythological concepts or characters; places, areas or countries; properties of the element or its compounds, such as color, smell or its inability to combine; and the names of scientists. There are also some miscellaneous names as well as some obscure names for particular elements. The claim of discovery of an element has varied over the centuries. Many claims, e.g., the discovery of certain rare earth elements of the lanthanide series, involved the discovery of a mineral ore from which an element was later extracted. The honor of discovery has often been accorded not to the person who first isolated the element but to the person who discovered the original mineral itself, even when the ore was impure and contained many elements. The reason for this is that in the case of these rare earth elements, the ''earth'' now refers to oxides of a metal not to the metal itself. This fact was not realized at the time of their discovery, until the English chemist Humphry Davy showed that earths were compounds of oxygen and metals in 1808. In the early discoveries, the atomic weight of an element and spectral analysis of the element were not available. Later both of these elemental properties would be required before discovery of the element would be accepted. In general, the requirements for discovery claims have tightened through the years and claims that were previously accepted would no longer meet the minimum constraints now imposed. There are cases where the honor of discovery is not given to the first person to actually discover the element but to the first person to claim the discovery in print. If a

HISTORY OF THE ORIGIN OF THE CHEMICAL ELEMENTS AND THEIR DISCOVERIES.

Energy Technology Data Exchange (ETDEWEB)

HOLDEN,N.E.

2001-06-29

The origin of the chemical elements show a wide diversity with some of these elements having their origin in antiquity. Still other elements have been synthesized within the past fifty years via nuclear reactions on heavy elements, because these other elements are unstable and radioactive and do not exist in nature. The names of the elements come from many sources including mythological concepts or characters; places, areas or countries; properties of the element or its compounds, such as color, smell or its inability to combine; and the names of scientists. There are also some miscellaneous names as well as some obscure names for particular elements. The claim of discovery of an element has varied over the centuries. Many claims, e.g., the discovery of certain rare earth elements of the lanthanide series, involved the discovery of a mineral ore from which an element was later extracted. The honor of discovery has often been accorded not to the person who first isolated the element but to the person who discovered the original mineral itself, even when the ore was impure and contained many elements. The reason for this is that in the case of these rare earth elements, the ''earth'' now refers to oxides of a metal not to the metal itself. This fact was not realized at the time of their discovery, until the English chemist Humphry Davy showed that earths were compounds of oxygen and metals in 1808. In the early discoveries, the atomic weight of an element and spectral analysis of the element were not available. Later both of these elemental properties would be required before discovery of the element would be accepted. In general, the requirements for discovery claims have tightened through the years and claims that were previously accepted would no longer meet the minimum constraints now imposed. There are cases where the honor of discovery is not given to the first person to actually discover the element but to the first person to claim the

Investigation on the loss of trace elements in biological materials in different drying and ashing procedures by using radioactive tracers: Pt. 1

International Nuclear Information System (INIS)

Wang Yongxian; Qin Junfa; Ji Qianmei; Wu Shimin; Wang Xuepeng; Zhang Yuanxun

1985-01-01

By using radioactive tracers it is found that freezing dry is safe for Zn, Mo, Cd and Se in all matrices studied. Oven dry is also safe except for Se in hair. The oxygen plasma ashing does not cause any loss of Zn, Mo and Cd. Different degrees of loss were observed in oven ashing with exception of Zn and Mo in hair and shallot. It is obvious that the loss rate of the trace elements depends on their chemical forms present in the matrices. The retention of the four elements studied on the wall of quartz container can be neglected after oxygen plasma ashing. But Zn, Cd and Mo were retended in various degrees after oven ashing

Chemical treatment of liquid radioactive waste at the Boris Kidric Institute

International Nuclear Information System (INIS)

Lazic, S.; Vukovic, Z.; Voko, A.

1989-01-01

The results of lab-scale experiments on the chemical treatment of radioactive liquid waste collected at the Boris Kidric Institute are presented. The radioactive waste was treated by cobalt hexacyanoferrate precipitation followed by flocculation with polyelectrolyte flocculating agents. The main parameters investigated were standing time, pH and ratio of reagents. The flocculating agents were tested by filtration test and floccule stability test. Satisfactory decontamination factors by precipitation at pH 10 and good separation of solid and liquid phase by applying Praestol polyelectrolytes were obtained (author)

Physical-chemical studies of transuranium elements: Progress report for the period April 1, 1985-March 31, 1988

International Nuclear Information System (INIS)

Peterson, J.R.

1987-01-01

New knowledge is being accumulated in the role of the 5f electrons in the bonding in actinide elements and compounds, the relationships of metallic structures to metallic valence and radius, the extent and magnitude of the actinide contraction, the magnetic, thermodynamic, spectroscopic, and crystallographic properties of these materials as related to general theories, the effect of self-irradiation on chemical and physical properties, the chemical and physical consequences of radioactive decay in the bulk-phase solid state, and in general, the range of validity of the actinide hypothesis. Separate reports are given on: spectrophotometric studies of Cf(III) ions in lanthanide trihalide hosts, new ternary transplutonium chalcogenide halides, Raman spectrometric studies of lanthanide trihalides as function of T or P, and solution calorimetry of californium halides

Synthesis and investigation of superheavy elements - perspectives with radioactive beams

International Nuclear Information System (INIS)

Muenzenberg, G.

1997-09-01

The perspectives for the investigation of heavy and superheavy elements with intense beams of radioactive nuclei available from the new generation of secondary beam facilities in combination with modern experimental developments are the subject of this paper. The nuclear properties of the recently discovered shell nuclei centered at Z=108 and N=164 and predictions on the location of the superheavy region with improved theoretical models will be discussed. (orig.)

Thermodynamic stability of radioactivity standard solutions

International Nuclear Information System (INIS)

Iroulard, M.G.

2007-04-01

The basic requirement when preparing radioactivity standard solutions is to guarantee the concentration of a radionuclide or a radioelement, expressed in the form of activity concentration (Ac = A/m (Bq/g), with A: activity and m: mass of solution). Knowledge of the law of radioactive decay and the half-life of a radionuclide or radioelement makes it possible to determine the activity concentration at any time, and this must be confirmed subsequently by measurement. Furthermore, when radioactivity standard solutions are prepared, it is necessary to establish optimal conditions of thermodynamic stability of the standard solutions. Radioactivity standard solutions are prepared by metrology laboratories from original solutions obtained from a range of suppliers. These radioactivity standard solutions must enable preparation of liquid and/or solid radioactivity standard sources of which measurement by different methods can determine, at a given instant, the activity concentration of the radionuclide or radioelement present in the solution. There are a number of constraints associated with the preparation of such sources. Here only those that relate to the physical and chemical properties of the standard solution are considered, and therefore need to be taken into account when preparing a radioactivity standard solution. These issues are considered in this document in accordance with the following plan: - A first part devoted to the chemical properties of the solutions: - the solubilization media: ultra-pure water and acid media, - the carriers: concentration, oxidation state of the radioactive element and the carrier element. - A second part describing the methodology of the preparation, packaging and storage of standard solutions: - glass ampoules: the structure of glasses, the mechanisms of their dissolution, the sorption phenomenon at the solid-solution interface, - quartz ampoules, - cleaning and packaging: cleaning solutions, internal surface coatings and

Thermodynamic stability of radioactivity standard solutions

Energy Technology Data Exchange (ETDEWEB)

Iroulard, M.G

2007-04-15

The basic requirement when preparing radioactivity standard solutions is to guarantee the concentration of a radionuclide or a radioelement, expressed in the form of activity concentration (Ac = A/m (Bq/g), with A: activity and m: mass of solution). Knowledge of the law of radioactive decay and the half-life of a radionuclide or radioelement makes it possible to determine the activity concentration at any time, and this must be confirmed subsequently by measurement. Furthermore, when radioactivity standard solutions are prepared, it is necessary to establish optimal conditions of thermodynamic stability of the standard solutions. Radioactivity standard solutions are prepared by metrology laboratories from original solutions obtained from a range of suppliers. These radioactivity standard solutions must enable preparation of liquid and/or solid radioactivity standard sources of which measurement by different methods can determine, at a given instant, the activity concentration of the radionuclide or radioelement present in the solution. There are a number of constraints associated with the preparation of such sources. Here only those that relate to the physical and chemical properties of the standard solution are considered, and therefore need to be taken into account when preparing a radioactivity standard solution. These issues are considered in this document in accordance with the following plan: - A first part devoted to the chemical properties of the solutions: - the solubilization media: ultra-pure water and acid media, - the carriers: concentration, oxidation state of the radioactive element and the carrier element. - A second part describing the methodology of the preparation, packaging and storage of standard solutions: - glass ampoules: the structure of glasses, the mechanisms of their dissolution, the sorption phenomenon at the solid-solution interface, - quartz ampoules, - cleaning and packaging: cleaning solutions, internal surface coatings and

A Model for determination of screening levels for radioactive elements in soil

International Nuclear Information System (INIS)

Peres, Ana C.; Hiromoto, Goro

2008-01-01

Full text: At the present, decision about clean-up of Brazilian sites contaminated with radioactive isotopes is addressed on a case-by-case basis, since there is no general guidance or recommendation to support actions in early phases of the problem identification. For chemicals, CETESB - the governmental organization responsible for preventing and controlling environmental pollution in Sao Paulo State - established quality reference values for prevention and intervention, as the first step to implement a remediation policy based on human health risk assessment. The aim of this study is to develop a methodology for the establishment of target values for radioactive soil contamination, as far as possible consistent and compatible with the approach adopted by CETESB for sites contaminated with chemicals. The following steps have been addressed in this study: conceptual scenario and model development; codification of the equations in an electronic spreadsheet; selection of proper input values; derivation of the intervention levels for selected radionuclides using Monte Carlo methods. The mathematical model developed was mainly based on the equations used by the U.S. Environmental Protection Agency and by the National Council on Radiation Protection and Measurements for soil screening purposes. Results are presented for selected natural and man-made radioactive isotopes. (author)

On the discovery of artificial radioactivity

International Nuclear Information System (INIS)

Guillaumont, R.; Trubert, D.

1997-01-01

A review is presented of the elegant Joliot-Curie physical experiments which showed for the first time the possibility of producing artificial radioactive nuclei. An attempt has been made to explain the results of their equally elegant chemical experiments that unequivocally demonstrated the chemical change of elements by nuclear processes. These experiments are discussed in the light of present-day radiochemistry, keeping in mind the scientific and historical context in which they were originally performed. (author)

Chemical and nuclear properties of lawrencium (element 103) and hahnium (element 105)

International Nuclear Information System (INIS)

Henderson, R.A.

1990-01-01

The chemical and nuclear properties of Lr and Ha have been studied, using 3-minute 260 Lr and 35-second 262 Ha. The crystal ionic radius of Lr 3+ was determined by comparing its elution position from a cation-exchange resin column with those of lanthanide elements having known ionic radii. Comparisons are made to the ionic radii of the heavy actinides, Am 3+ through Es 3+ , obtained by x-ray diffraction methods, and to Md 3+ and Fm 3+ which were determined in the same manner as Lr 3+ . The hydration enthalpy of -3622 kJ/mol was calculated from the crystal ionic radius using an empirical form of the Born equation. Comparisons to the spacings between the ionic radii of the heaviest members of the lanthanide series show that the 2Z spacing between Lr 3+ and Md 3+ is anomalously small, as the ionic radius of Lr 3+ of 0.0886 nm is significantly smaller than had been expected. The chemical properties of Ha were determined relative to the lighter homologs in group 5, Nb and Ta. Group 4 and group 5 tracer activities, as well as Ha, were absorbed onto glass surfaces as a first step toward the determination of the chemical properties of Ha. Ha was found to adsorb on surfaces, a chemical property unique to the group 5 elements, and as such demonstrates that Ha has the chemical properties of a group 5 element. A solvent extraction procedure was adapted for use as a micro-scale chemical procedure to examine whether or not Ha displays eka-Ta-like chemical under conditions where Ta will be extracted into the organic phase and Nb will not. Under the conditions of this experiment Ha did not extract, and does not show eka-Ta-like chemical properties

Radioactive and hazardous chemical wastes. Impact on man and his environment

International Nuclear Information System (INIS)

Parker, F.L.; Suess, M.J.

1984-01-01

The main objective of the various safety measures in all fields of human activities is to prevent deleterious effects of various agents on human health. Preventive health and safety measures therefore play an important role in achieving the main goal of the World Health Organization (WHO): 'Health for all by the year 2000'. The present WHO programme on environmental health emphasizes the prevention of chemical hazards as one of the most important environmental factors affecting human health. At the same time, protection from physical factors, including radiological protection, is part of this programme. Therefore, WHO compares health detriments from both physical and chemical agents. The paper describes the hazardous waste problems of great concern in industrialized countries. For instance, the Commission of the European Communities countries produce about 2x10 9 tonnes of waste per year, a rate which grows by 2 to 3% annually. This poses serious problems of pollution, particularly where the toxic ingredients do not decay. Special attention will also be given to the safe handling of high-level radioactive waste from the peaceful use of nuclear technology. These wastes have to be stored in safe storage facilities, or be disposed of without causing damage to man and his environment. The international measures to contain and control these wastes are described, including the activities of WHO within the Global Environmental Monitoring System and Regional Sea programmes of the United Nations Environment Programme. Guidelines and methodologies for the management of hazardous chemical and radioactive wastes are being developed through WHO to assist national authorities in this task. The paper pays special attention to a comparative assessment of environmental and public health impacts of toxic chemical and radioactive wastes. (author)

Radioactivity in chemical and organic fertilizer used in Egypt

International Nuclear Information System (INIS)

Abbady, A.G.E.; Yousef, A.M.M.; Abbady, A.; El-Taher, A.

2005-01-01

The Egypt Chemical factories (ECF); such as Talkha, Sues, Abo Qeyer, Kafer Elzayat, and Assuit factories, produces and markets a range of phosphate based fertilizers, including Simple Super Phosphate (SSP) fertilizer, Triple Super Phosphate (TSP) fertilizer and Urea. Phosphate fertilizers produced by ECF are derived from phosphate ore. In addition to phosphate minerals, these ores can contain significant amounts of a wide range of impurities, including heavy metals and naturally occurring radionuclides. This study was carried out to determine the content of radionuclides in fertilizer products produced by ECF and some organic fertilizer (animal manure) includes cow, sheep and chicken fertilizer. In both samples (Chemical and organic fertilizers), the activity concentrations of Ra 2 26 are higher than those Th 2 32. The radioactivity of 226 R a in chemical fertilizers ranged from 21.6 ± 3.6 to 111.2 ± 8.9 Bq kg-1, phosphate fertilizers TSP contained high contents of 226 R a. The average radioactivity of 226 R a in TSP was 79.3 ± 7.4 Bq kg-1, in SSP 51.2 ± 5 Bq kg-1, and in Urea 35.1± 3.5 Bq kg-1. The activity of 232 T h in the different fertilizers ranged from 1.3 ± 1.1 to 9.9 ± 3.2 Bq kg-1,the highest activity observed in SSP fertilizer. The activity of 40 K was found to be great in the TSP fertilizer, which contained a mean activity 478.1± 21.3 Bq kg-1. With respect to organic fertilizers the average radioactivity of 226 R a, 232 T h and 40 K are 40 ± 1.6 Bq kg-1, 3.1± 1.2 and 427.1± 20 Bq kg-1. The data are discussed and compared with those given in the literatures. This study could be useful as baseline data for radiation exposure to fertilizers, and their impact on human health

Electronic Transmutation (ET): Chemically Turning One Element into Another.

Science.gov (United States)

Zhang, Xinxing; Lundell, Katie A; Olson, Jared K; Bowen, Kit H; Boldyrev, Alexander I

2018-03-08

The concept of electronic transmutation (ET) depicts the processes that by acquiring an extra electron, an element with the atomic number Z begins to have properties that were known to only belong to its neighboring element with the atomic number Z+1. Based on ET, signature compounds and chemical bonds that are composed of certain elements can now be designed and formed by other electronically transmutated elements. This Minireview summarizes the recent developments and applications of ET on both the theoretical and experimental fronts. Examples on the ET of Group 13 elements into Group 14 elements, Group 14 elements into Group 15 elements, and Group 15 elements into Group 16 elements are discussed. Compounds and chemical bonding composed of carbon, silicon, germanium, phosphorous, oxygen and sulfur now have analogues using transmutated boron, aluminum, gallium, silicon, nitrogen, and phosphorous. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Los Alamos Controlled Air Incinerator for hazardous chemical and mixed radioactive wastes

International Nuclear Information System (INIS)

Vavruska, J.S.; Borduin, L.C.; Hutchins, D.A.; Koenig, R.A.; Warner, C.L.

1986-01-01

The Los Alamos Controlled Air Incinerator (CAI) is currently the only radioactive waste incineration facility in the US permitted to treat polychlorinated biphenyls (PCBs). The CAI was developed in the mid-1970's as a demonstration system for volume reduction of transuranic (TRU) contaminated combustible solid wastes. It has since undergone additions and modifications to accommodate hazardous chemical wastes in response to a need within the Department of Energy (DOE) to treat mixed radioactive/chemical wastes. An overview of these additions which include a liquid feed system, a high intensity liquid injection burner, and an activated carbon adsorption unit is presented here. Also included is a discussion of the procedures required for Toxic Substances Control Act (TSCA) and Resource Conservation and Recovery Act (RCRA) permitting of the CAI

Gold and radioactive elements in the bauxite deposits of Shevaroy hills, Tamil Nadu

Energy Technology Data Exchange (ETDEWEB)

Mukherjee, B K; Sengupta, D K

1982-11-01

The presence of gold and radioactive elements in the bauxite deposits of Shevaroy Hills has been determined by neutron activation technique. The behaviour of uranium supports the theoretical findings. The higher concentration of gold (<10/sup 3/%) indicates that the deposits are auriferous.

Gold and radioactive elements in the bauxite deposits of Shevaroy hills, Tamil Nadu

International Nuclear Information System (INIS)

Mukherjee, B.K.; Sengupta, D.K.

1982-01-01

The presence of gold and radioactive elements in the bauxite deposits of Shevaroy Hills has been determined by neutron activation technique. The behaviour of uranium supports the theoretical findings. The higher concentration of gold ( -3 %) indicates that the deposits are auriferous. (author)

Determination of natural radioactivity and the concentration of elements in soil and plants at Krau Wildlife Reserve, Temerloh, Pahang

International Nuclear Information System (INIS)

Hafiz Hadzori

2012-01-01

This study was conducted to determine the natural radioactivity and the concentration of elements in soil and plants at Krau Wildlife Reserve, Pahang. Soil and plant samples collected were air dried and heated in the oven at temperature of 100 degree Celsius. Inductively Coupled Plasma Mass-Spectrometer (ICP-MS) was used to determine the natural radioactivity and elemental contents of each sample. Results showed that the concentration of U-238 and Th-232 varied from each sampling site. The concentration of Th-232 is higher than of U-238. For soil and plants samples, the natural radioactivity for both radionuclides were below 72 Bq/ kg. 15 elements present in both soil and plant samples, among other are Al, Fe, K, Mg, Mn, Ca, Zn, Co, Cd and As. The concentration of each elements differs for every sampling site. The elements with higher concentration are Al, Ca, Fe, K, Mg and Mn. This study showed that monocotyledon taking up more Mg than dicotyledons whereas dicotyledon plants taking up more Al. (author)

Nuclear radioactive techniques applied to materials research

CERN Document Server

Correia, João Guilherme; Wahl, Ulrich

2011-01-01

In this paper we review materials characterization techniques using radioactive isotopes at the ISOLDE/CERN facility. At ISOLDE intense beams of chemically clean radioactive isotopes are provided by selective ion-sources and high-resolution isotope separators, which are coupled on-line with particle accelerators. There, new experiments are performed by an increasing number of materials researchers, which use nuclear spectroscopic techniques such as Mössbauer, Perturbed Angular Correlations (PAC), beta-NMR and Emission Channeling with short-lived isotopes not available elsewhere. Additionally, diffusion studies and traditionally non-radioactive techniques as Deep Level Transient Spectroscopy, Hall effect and Photoluminescence measurements are performed on radioactive doped samples, providing in this way the element signature upon correlation of the time dependence of the signal with the isotope transmutation half-life. Current developments, applications and perspectives of using radioactive ion beams and tech...

Inconsistency... or why differentiate, where prevention is concerned, between radioactive substances and carcinogenic chemicals

International Nuclear Information System (INIS)

Choquet, R.; Vinit, J.

1982-01-01

Radiotracers, low-activity unsealed radioactive sources, and certain chemical products belong to the list of substances and agents known to promote cancers in humans. The dangers of radiotracers and carcinogenic chemicals being very similar, or even identical, it is inadmissible that preventive measures have not been equally developed and are not viewed in the same way in our country. It should be noted that the International Labour Bureau has long since included radioactive products in the list of carcinogenic substances and agents and treated preventive measures as a whole by proceeding in this way it would be easier to account for the possible combined effects of ionising radiations and chemical molecules. After a review of some facts about cancer the present situation is examined with regard to statutory measures applied on the one hand to radioelements and on the other to chemicals recognised as carcinogenic by international organisations. Proposals are made to remedy this illogical situation [fr

Store for radioactive waste and burnt-up fuel elements

International Nuclear Information System (INIS)

Spilker, H.; Rox, R.; Peschl, H.W.

1985-01-01

The invention concerns a concrete storage block in which there are several vertical storage and cooling ducts for radioactive waste and burnt-up fuel elements. The storage block is assembled from several square concrete blocks. Several vertical ducts are made in these. The square blocks are placed on a concrete baseplate. The aligned ducts of several square blocks placed above each other form storage and cooling ducts for tubular storage containers. An annular gap is left for cooling air between the outside wall of the storage containers and the inside wall of the storage and cooling ducts. (orig./HP) [de

Elemental and radioactive analysis of commercially available seaweed

International Nuclear Information System (INIS)

Van Netten, C.; Hoption Cann, S.A.; Van Netten, J.P.; Morley, D.R.

2000-01-01

Edible seaweed products have been used in many countries, specifically Japan, as a food item. Recently these products have become popular in the food industry because of a number of interesting medicinal properties that have been associated with certain edible marine algae. Very little control exists over the composition of these products, which could be contaminated with a number of agents including heavy metals and certain radioactive isotopes. Fifteen seaweed samples (six local samples from the coast of British Columbia, seven from Japan, one from Norway and one undisclosed) were obtained. All samples were analyzed for multiple elements, using ICP mass spectrometry and for radioactive constituents. It was found that six of eight imported seaweed products had concentrations of mercury orders of magnitude higher than the local products. Lead was found at somewhat higher concentrations in only one local product. Laminaria japonica had the highest level of iodine content followed by Laminaria setchellii from local sources. Only traces of cesium-137 were found in a product from Norway and radium-226 was found in a product from Japan. Arsenic levels were found to be elevated. In order to estimate the effect of these levels on health, one needs to address the bioavailability and the speciation of arsenic in these samples

Elemental and radioactive analysis of commercially available seaweed

Energy Technology Data Exchange (ETDEWEB)

Van Netten, C. [Department of Health Care and Epidemiology, James Mather Building, University of British Columbia, 5804 Fairview Avenue, V6T 1Z3 Vancouver, BC (Canada); Hoption Cann, S.A.; Van Netten, J.P. [Special Development Laboratory, Royal Jubilee Hospital, V8X 1P2 Victoria, BC (Canada); Morley, D.R. [Radiation Protection Branch, Ministry of Health, 4940 Canada Way, V5G 4K6 Burnaby, BC (Canada)

2000-06-08

Edible seaweed products have been used in many countries, specifically Japan, as a food item. Recently these products have become popular in the food industry because of a number of interesting medicinal properties that have been associated with certain edible marine algae. Very little control exists over the composition of these products, which could be contaminated with a number of agents including heavy metals and certain radioactive isotopes. Fifteen seaweed samples (six local samples from the coast of British Columbia, seven from Japan, one from Norway and one undisclosed) were obtained. All samples were analyzed for multiple elements, using ICP mass spectrometry and for radioactive constituents. It was found that six of eight imported seaweed products had concentrations of mercury orders of magnitude higher than the local products. Lead was found at somewhat higher concentrations in only one local product. Laminaria japonica had the highest level of iodine content followed by Laminaria setchellii from local sources. Only traces of cesium-137 were found in a product from Norway and radium-226 was found in a product from Japan. Arsenic levels were found to be elevated. In order to estimate the effect of these levels on health, one needs to address the bioavailability and the speciation of arsenic in these samples.

Report on the disposal of radioactive wastes and spent fuel elements from Baden-Wuerttemberg; Bericht ueber die Entsorgung von radioaktiven Abfaellen und abgebrannten Brennelementen aus Baden-Wuerttemberg

Energy Technology Data Exchange (ETDEWEB)

NONE

2017-04-15

The report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg covers the following issues: legal framework for the nuclear disposal; producer of spent fuels and radioactive wastes in Baden- Report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg; low- and medium-level radioactive wastes (non heat generating radioactive wastes); spent fuels and radioactive wastes from waste processing (heat generating radioactive wastes); final disposal.

Behavior of rare earth elements in fractured aquifers: an application to geological disposal criteria for radioactive waste

International Nuclear Information System (INIS)

Lee, Seung Gu; Kim, Yong Je; Lee, Kil Yong; Kim, Kun Han

2003-01-01

An understanding of the geochemistry of potential host rocks is very important in the site evaluation for construction of an underground geologic repository for radioactive waste. Because of similar valence and ionic radii and high similarity in electronic structure with trivalent actinides (such as Am 3+ and Cm 3+ ), the rare earth elements (REEs) have been used to predict the behavior of actinide-series elements in solution (Runde et al., 1992). For Am and Cm, which occur only in the trivalent states in most waste-disposal repository environments, the analogy with the REEs is particularly relevant. In order to discuss the behavior of REEs in geological media and to deduce the behavior of actinides in geological environments based on the REE abundance, and to provide an useful tool in deciding an optimum geological condition for radioactive disposal, we estimated the REE abundance from various kinds of fractured rock type. In fractured granitic aquifer, chondrite-normalized REE pattern show Eu positive anomaly due to fracture-filling calcite precipitation. However, in fractured meta-basaltic and volcanic tuffaceous aquifer, REE pattern do not show the change of Eu anomaly due to fracture-filling calcite precipitation. Eu shows very similar properties such as cohesive energy, ionic radii with coordination number compared to Am. Therefore, if we consider the Eu behavior in fractured rocks and the similar physical/chemical properties of Eu and Am, together, our results strongly suggest that Eu is a very useful analogue for predicting the behavior of Am in geological environment

Groundwater flow analysis using mixed hybrid finite element method for radioactive waste disposal facilities

International Nuclear Information System (INIS)

Aoki, Hiroomi; Shimomura, Masanori; Kawakami, Hiroto; Suzuki, Shunichi

2011-01-01

In safety assessments of radioactive waste disposal facilities, ground water flow analysis are used for calculating the radionuclide transport pathway and the infiltration flow rate of groundwater into the disposal facilities. For this type of calculations, the mixed hybrid finite element method has been used and discussed about the accuracy of ones in Europe. This paper puts great emphasis on the infiltration flow rate of groundwater into the disposal facilities, and describes the accuracy of results obtained from mixed hybrid finite element method by comparing of local water mass conservation and the reliability of the element breakdown numbers among the mixed hybrid finite element method, finite volume method and nondegenerated finite element method. (author)

Bio indicator organisms available to use for determination of radioactive elements in Turkey's seas

International Nuclear Information System (INIS)

Kocbas, F.; Guener, H.

2006-01-01

In determination of radioactive concentration and monitoring alive and lifeless environmental samples possess a significant place. Thus, intense study is carried out related to natural and artificial radionuclides sediment. Bio indicator living organisms inhabiting in sea ecosystems; are being evaluated in researches such as determinations of environmental pollution, natural and artificial radioactive elements. Turkey's seas are rich related to diversification of various types. In determining and monitoring radioactivity concentration widespread implementation of some sorts appeal attention and on the other hand inadequate usage of many types is observed. In the present study, providing information about the bio indicator organisms keep living in seas and plays important role in food supply chain and increasing the numbers of the types of organisms used are aimed

Content of Chemical Elements in Wood-Destroying Fungi

Directory of Open Access Journals (Sweden)

Strapáč I.

2016-12-01

Full Text Available The aim of this study was to examine the content of chemical elements in the dried fruiting bodies of edible wood decaying fungi such as Honey mushrooms (Armillaria mellea, Shiitakes (Lentinus edodes and Oyster mushrooms (Pleurotus ostreatus. Powdered samples of fungi were mineralized in a microwave digestion. Twenty-one (21 chemical elements were detected in the plasma of the device ICP-MS AGILENT 7500c by accredited methods with the aid of calibration curves. The content of individual elements varied within a considerable range. The highest contents of K, Mn, Cu and Cd were found in the fruiting bodies of Honey mushrooms (Armillaria mellea. Shiitakes (Lentinus edodes had the highest content of B and Mo. Significant differences were found in the content of elements in the Oyster mushrooms (Pleurotus ostreatus from Slovakia, Hungary and China. The highest content of Al was found in the Oyster mushrooms (Pleurotus ostreatus from Hungary. The Chinese oysters had a maximum contents of Ca, Mg, Co, Pb, As and U. The Oyster mushrooms (Pleurotus ostreatus from Lemešany (Slovakia had the highest contents of Na, Zn, Fe, Se, Ag, Hg and Cr. The difference of chemical element content could be influenced by the genotype of the fungus and by the composition of substrate on which mushroom grow up.

EDXRF for determination of chemical elements in the beetle Alphitobius diaperinus

International Nuclear Information System (INIS)

Cantinha, Rebeca S.; Farias, Emerson E.G. de; Magalhaes, Marcelo L.R. de; Franca, Elvis J. de; Cunha, Franklin M. da; Zacarias, Vyvyane L.

2015-01-01

Energy Dispersion X-Ray Fluorescence (EDXRF) spectrometry has been widely employed for chemical element determination of biological matrices, including insects. The beetle Alphitobius diaperinus is a major problem in poultry production, thereby infesting poultry litter and stored grains. Up to now, little is known about the behavior, physiology and environmental interactions of this insect. In this paper, EDXRF was applied to quantify the main chemical elements in A. diaperinus. For the quality of the analytical protocol, certified reference materials produced by National Institute of Standards and Technology - NIST were analyzed together with the samples. The technique was able to quantify Cl, P, S and Zn in this insect, presenting no significant variation at the 95% confidence level among the repetitions (n = 4). A different pattern of chemical element accumulation in this beetle was noticed compared to other Coleoptera species, in which the concentration of the chemical elements were markedly lower in A. diaperinus, probably associated to the restricted availability of chemical elements in food. Since no result has been found in the literature before, A. diaperinus was firstly chemically characterized in this paper. (author)

EDXRF for determination of chemical elements in the beetle Alphitobius diaperinus

Energy Technology Data Exchange (ETDEWEB)

Cantinha, Rebeca S.; Farias, Emerson E.G. de; Magalhaes, Marcelo L.R. de; Franca, Elvis J. de, E-mail: rebecanuclear@gmail.com, E-mail: emersonemiliano@yahoo.com.br, E-mail: marcelo_rlm@hotmail.com, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Cunha, Franklin M. da; Zacarias, Vyvyane L., E-mail: ukento@yahoo.com.br, E-mail: vyvyanebiologicas@gmail.com [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil)

2015-07-01

Energy Dispersion X-Ray Fluorescence (EDXRF) spectrometry has been widely employed for chemical element determination of biological matrices, including insects. The beetle Alphitobius diaperinus is a major problem in poultry production, thereby infesting poultry litter and stored grains. Up to now, little is known about the behavior, physiology and environmental interactions of this insect. In this paper, EDXRF was applied to quantify the main chemical elements in A. diaperinus. For the quality of the analytical protocol, certified reference materials produced by National Institute of Standards and Technology - NIST were analyzed together with the samples. The technique was able to quantify Cl, P, S and Zn in this insect, presenting no significant variation at the 95% confidence level among the repetitions (n = 4). A different pattern of chemical element accumulation in this beetle was noticed compared to other Coleoptera species, in which the concentration of the chemical elements were markedly lower in A. diaperinus, probably associated to the restricted availability of chemical elements in food. Since no result has been found in the literature before, A. diaperinus was firstly chemically characterized in this paper. (author)

Chemical reactivity of precursor materials during synthesis of glasses used for conditioning high-level radioactive waste: Experiments and models

International Nuclear Information System (INIS)

Monteiro, A.

2012-01-01

The glass used to store high-level radioactive waste is produced by reaction of a solid waste residue and a glassy precursor (glass frit). The waste residue is first dried and calcined (to lose water and nitrogen respectively), then mixed with the glass frit to enable vitrification at high temperature. In order to obtain a good quality glass of constant composition upon cooling, the chemical reactions between the solid precursors must be complete while in the liquid state, to enable incorporation of the radioactive elements into the glassy matrix. The physical and chemical conditions during glass synthesis (e.g. temperature, relative proportions of frit and calcine, amount of radioactive charge) are typically empirically adjusted to obtain a satisfactory final product. The aim of this work is to provide new insights into the chemical and physical interactions that take place during vitrification and to provide data for a mathematical model that has been developed to simulate the chemical reactions. The consequences of the different chemical reactions that involve solid, liquid and gaseous phases are described (thermal effects, changes in crystal morphology and composition, variations in melt properties and structure). In a first series of experiments, a simplified analogue of the calcine (NaNO 3 -Al 2 O 3 ± MoO 3 /Nd 2 O 3 ) has been studied. In a second series of experiments, the simplified calcines have been reacted with a simplified glass frit (SiO 2 -Na 2 O-B 2 O 3 -Al 2 O 3 ) at high temperature. The results show that crystallization of the calcine may take place before interaction with the glass frit, but that the reactivity with the glass at high temperature is a function of the nature and stoichiometry of the crystalline phases which form at low temperature. The results also highlight how the mixing of the starting materials, the physical properties of the frit (viscosity, glass transition temperature) and the Na 2 O/Al 2 O 3 of the calcine but also its

Recommended inorganic chemicals for calibration

International Nuclear Information System (INIS)

Moody, J.R.; Greenberg, R.R.; Pratt, K.W.; Rains, T.C.

1988-01-01

All analytical techniques depend on the use of calibration chemicals to relate analyte concentration to an instrumental parameter. A fundamental component in the preparation of calibration solutions is the weighing of a pure chemical or metal before preparing a solution standard. The analyst must be assured that the purity, stoichiometry, and assay of the chemical are known. These terms have different meanings, and each has an important influence. This report is intended to assist the analyst in the selection and use of chemical standards for instrumental calibration. Purity, stoichiometry, and preparation of solutions for different purposes are discussed, and a critical evaluation of the best materials available for each element is presented for use in preparing solutions or calibration standards. Information on the chemical form, source, purity, drying, and appropriate precautions is given. In some cases, multiple sources or chemical forms are available. Certain radioactive elements, the transuranic elements, and the noble gases are not considered

The French national inventory of radioactive waste. Elements of openness and responsibility

International Nuclear Information System (INIS)

Faussat, A.; Fernique, J.C.

1995-01-01

Article 13 of the Waste Act of 30 December 1991 calls for the Agence nationale pour la gestion des dechets radioactifs (ANDRA) ''to register the condition and location of all radioactive waste on national territory''. The establishment of a national inventory of radioactive waste and the broad distribution of inventory report to ensure that it becomes a matter of public record constitute a new approach to public information and an effective means of fulfilling the responsibility of the present generation vis-a-vis posterity. The National Waste Register goes beyond the low level radioactive waste disposal facilities to encompass 'all' waste, wherever it may be, including waste in storage at sites where waste is produced. As a result, the Register is multi-faceted, containing information on a variety of elements, from highly radioactive waste to hospital waste collected by ANDRA and to repositories with very low level radioactive material. Information must be provided about all of these widely divergent components. ANDRA has already published two inventories, which demonstrates the durability of its new mission. The Register now contains the inventory of radioactive waste generated by some activities connected with the defence programme. Data collection for the Register involves contacting the generators of waste and working with these entities, whether they are nuclear industry companies, defence organizations, non-nuclear industries, or the 25 Regional Directorates of Industry, Research and Environment, the control institutions or the environmental protection organizations. The yearly exchange of information among all partners involved in radioactive waste management is one of the basic tools of ANDRA, allowing it to be recognized as open and responsible, and to be more credible, fulfilling in this way one of the essential criteria for acceptability. (author). 4 refs

PIXE - a new method for elemental analysis

International Nuclear Information System (INIS)

Johansson, S.A.E.

1983-01-01

With elemental analysis we mean the determination of which chemical elements are present in a sample and of their concentration. This is an old and important problem in chemistry. The earliest methods were purely chemical and many such methods are still used. However, various methods based on physical principles have gradually become more and more important. One such method is neutron activation. When the sample is bombarded with neutrons it becomes radioactive and the various radioactive isotopes produced can be identified by the radiation they emit. From the measured intensity of the radiation one can calculate how much of a certain element that is present in the sample. Another possibility is to study the light emitted when the sample is excited in various ways. A spectroscopic investigation of the light can identify the chemical elements and allows also a determination of their concentration in the sample. In the same way, if a sample can be brought to emit X-rays, this radiation is also characteristic for the elements present and can be used to determine the elemental concentration. One such X-ray method which has been developed recently is PIXE. The name is an acronym for Particle Induced X-ray Emission and indicates the principle of the method. Particles in this context means heavy, charged particles such as protons and a-particles of rather high energy. Hence, in PIXE-analysis the sample is irradiated in the beam of an accelerator and the emitted X-rays are studied. (author)

Management of radioactive liquid waste at the Idaho Chemical Processing Plant

International Nuclear Information System (INIS)

Bendixsen, C.L.

1992-01-01

Highly radioactive liquid wastes (HLLW) are routinely produced during spent nuclear fuel processing at the Idaho Chemical Processing Plant (ICPP), located at the Idaho National Engineering Laboratory (INEL). This paper discusses the processes and safe practices for management of the radioactive process waste streams, which processes include collection, concentration, interim storage, calcination to granular solids, and long-term intermediate storage. Over four million gallons of HLLW have been converted to a recoverable granular solid form through waste liquid injection into a high-temperature, fluidized bed wherein the wastes are converted to their respective solid oxides. The development of a glass ceramic solid for the long-term permanent disposal of the high level waste (HLW) solids is also described

Radioactive ion beams and techniques for solid state research

International Nuclear Information System (INIS)

Correia, J.G.

1998-01-01

In this paper we review the most recent and new applications of solid state characterization techniques using radioactive ion beams. For such type ofresearch, high yields of chemically clean ion beams of radioactive isotopesare needed which are provided by the on-line coupling of high resolution isotope separators to particle accelerators, such as the isotope separator on-line (ISOLDE) facility at CERN. These new experiments are performed by an increasing number of solid state groups. They combine nuclear spectroscopic techniques such as Moessbauer, perturbed angular correlations (PAC) and emission channeling with the traditional non-radioactive techniques liked deep level transient spectroscopy (DLTS) and Hall effect measurements. Recently isotopes of elements, not available before, were successfully used in new PAC experiments, and the first photoluminescence (PL) measurements, where the element transmutation plays the essential role on the PL peak identification, have been performed. The scope of applications of radioactive ion beams for research in solid state physics will be enlarged in the near future, with the installation at ISOLDE of a post-accelerator device providing radioactive beams with energies ranging from a few keV up to a few MeV. (orig.)

Fractionation of chemical elements including the REEs and 226Ra in stream contaminated with coal-mine effluent

International Nuclear Information System (INIS)

Centeno, L.M.; Faure, G.; Lee, G.; Talnagi, J.

2004-01-01

Water draining from abandoned open-pit coal mines in southeastern Ohio typically has a low pH and high concentrations of Fe, Al and Mn, as well as of trace metals (Pb, Cu, Zn, Ni, Co, etc.) and of the rare earth elements (REEs). The cations of different elements are sorbed selectively by Fe and Al hydroxide precipitates which form with increasing pH. As a result, the trace elements are separated from each other when the hydroxide precipitates are deposited in the channel of a flowing stream. Therefore, the low-energy environment of a stream contaminated by mine effluent is a favorable site for the chemical fractionation of the REEs and of other groups of elements with similar chemical properties. The interpretation of chemical analyses of water collected along a 30-km-stretch of Rush Creek near the town of New Lexington, Perry County, Ohio, indicates that the abundances of the REEs in the water appear to change downstream when they are normalized to the REE concentrations of the mine effluent. In addition, the Ce/La ratios (and those of all REEs) in the water decrease consistently downstream. The evidence indicates that the REEs which remain in solution are enriched La and Ce because the other REEs are sorbed more efficiently. The solid Fe(OH) 3 precipitates in the channel of Rush Creek upstream of New Lexington also contain radioactive 226 Ra that was sorbed from the water. This isotope of Ra is a decay product of 238 U which occurs in the Middle Pennsylvanian (Upper Carboniferous) coal and in the associated shale of southeastern Ohio. The activity of 226 Ra of the Fe(OH) 3 precipitates increases with rising pH, but then declines farther downstream as the concentration of Ra remaining in the water decreases

Distribution of natural radioactive and trace elements in the soils and sands from the high radiation coastal belt of India

International Nuclear Information System (INIS)

Kulkarni, V.V.; Pillai, T.N.V.; Ganguly, A.K.

1974-01-01

A brief introduction of the work, already done in connection with the radioactivity present in soils in India, is given. Thorium daughter product activity is estimated in samples collected from monazite area, using gamma spectrometry. The activity is estimated quantitatively and the external dose as well as the genetically significant dose are calculated. Labile components in field soils and beach sands are estimated and the elements are analysed. The experimental procedure adopted is also described. The physico-chemical investigations carried out are explained with reference to the base exchange capacity, loss on ignition, particle size analysis, etc. The results have been presented in the form of tables and they are discussed in detail. (K.B.)

k{sub 0}-INAA for determining chemical elements in bird feathers

Energy Technology Data Exchange (ETDEWEB)

Franca, Elvis J., E-mail: ejfranca@usp.b [CENA/USP, Centro de Energia Nuclear na Agricultura, Universidade of Sao Paulo, P.O. Box 97, 13400-970, Piracicaba, SP (Brazil); Fernandes, Elisabete A.N.; Fonseca, Felipe Y. [CENA/USP, Centro de Energia Nuclear na Agricultura, Universidade of Sao Paulo, P.O. Box 97, 13400-970, Piracicaba, SP (Brazil); Antunes, Alexsander Z. [IF, Instituto Florestal do Estado de Sao Paulo, Rua do Horto 931, Horto Florestal 02377-000, Sao Paulo, SP (Brazil); Bardini Junior, Claudiney; Bacchi, Marcio A.; Rodrigues, Vanessa S.; Cavalca, Isabel P.O. [CENA/USP, Centro de Energia Nuclear na Agricultura, Universidade of Sao Paulo, P.O. Box 97, 13400-970, Piracicaba, SP (Brazil)

2010-10-11

The k{sub 0}-method instrumental neutron activation analysis (k{sub 0}-INAA) was employed for determining chemical elements in bird feathers. A collection was obtained taking into account several bird species from wet ecosystems in diverse regions of Brazil. For comparison reason, feathers were actively sampled in a riparian forest from the Marins Stream, Piracicaba, Sao Paulo State, using mist nets specific for capturing birds. Biological certified reference materials were used for assessing the quality of analytical procedure. Quantification of chemical elements was performed using the k{sub 0}-INAA Quantu Software. Sixteen chemical elements, including macro and micronutrients, and trace elements, have been quantified in feathers, in which analytical uncertainties varied from 2% to 40% depending on the chemical element mass fraction. Results indicated high mass fractions of Br (max=7.9 mg kg{sup -1}), Co (max=0.47 mg kg{sup -1}), Cr (max=68 mg kg{sup -1}), Hg (max=2.79 mg kg{sup -1}), Sb (max=0.20 mg kg{sup -1}), Se (max=1.3 mg kg{sup -1}) and Zn (max=192 mg kg{sup -1}) in bird feathers, probably associated with the degree of pollution of the areas evaluated. In order to corroborate the use of k{sub 0}-INAA results in biomonitoring studies using avian community, different factor analysis methods were used to check chemical element source apportionment and locality clustering based on feather chemical composition.

Soil-leaf transfer of chemical elements for the Atlantic Forest

International Nuclear Information System (INIS)

Joacir De Franca, E.; De Nadai Fernandes, E.A.; Bacchi, M.A.; Tagliaferro, F.S.

2007-01-01

Soil analysis could improve environmental studies since soil is the main source of chemical elements for plants. In this study, soil samples collected at 0-10 cm depth under tree crown projection were analyzed by INAA. Using the chemical composition of the leaf previously determined, the leaf-soil transfer factors of chemical elements could be estimated for the Atlantic Forest. Despite the variability of the intra-species, the transfer factors were specific for some plant species due to their element accumulation in the leaves. Similar Br-Zn combined transfer factors were obtained for the species grouped according to habitats in relation to their position (understory or dominant species) in the forest canopy. (author)

Guidelines for generators of hazardous chemical waste at LBL and Guidelines for generators of radioactive and mixed waste at LBL

International Nuclear Information System (INIS)

1991-07-01

The purpose of this document is to provide the acceptance criteria for the transfer of hazardous chemical, radioactive, and mixed waste to Lawrence Berkeley Laboratory's (LBL) Hazardous Waste Handling Facility (HWHF). These guidelines describe how a generator of wastes can meet LBL's acceptance criteria for hazardous chemical, radioactive, and mixed waste. 9 figs

Analysis of determination modalities concerning the exposure and emission limits values of chemical and radioactive substances

International Nuclear Information System (INIS)

Schieber, C.; Schneider, T.

2002-08-01

This document presents the generic approach adopted by various organizations for the determination of the public exposure limits values to chemical and radioactive substances and for the determination of limits values of chemical products emissions by some installations. (A.L.B.)

Using radioactivity

International Nuclear Information System (INIS)

1982-10-01

The leaflet discusses the following: radioactivity; radioisotopes; uses of ionising radiations; radioactivity from (a) naturally occurring radioactive elements, and (b) artificially produced radioisotopes; uses of radioactivity in medicine, (a) clinical diagnostic, (b) therapeutic (c) sterilization of medical equipment and materials; environmental uses as tracers; industrial applications, e.g. tracers and radiography; ensuring safety. (U.K.)

Chemical speciation of trace transition elements and iodine in freshwater at Rokkasho

International Nuclear Information System (INIS)

Takaku, Yuichi; Ohtsuka, Yoshihito; Hisamatsu, Shun'ichi

2007-01-01

Analytical methods for physicochemical speciation of radioactive and related materials, such as lanthanide, actinide and transition metals in environmental samples, were developed to elucidate behavior of radioactive materials in the environment. An inductively coupled plasma mass spectrometer (ICP-MS) was combined with a high-performance liquid chromatographer with a size exclusion (SEC) column or capillary electrophoresis apparatus (CE). Analytical methods using SEC-ICP-MS and CE-ICP-MS were developed for speciation of transition elements and iodine in environmental water samples in fiscal year 2004. The methods were applied to freshwater samples in Rokkasho; the results are reported here. Freshwater samples were collected from two lakes and three rivers surrounding the large-scale spent nuclear fuel reprocessing plant at Rokkasho. After samples were filtered with a membrane filter with 0.45 μm of pore size, large organic molecules were concentrated 200 times using an ultrafilter with a 10 kDa cutoff size. The concentrated solution was used for molecular size analyses using the SEC-ICP-MS technique. Molecular size chromatograms of all river and lake water samples showed two peaks of UV absorptions and concentrations of all transition elements analyzed: 30 kDa and >700 kDa peaks. Ratios of the transition element concentration in 30 kDa peak to that in both peaks varied greatly depending on the element and season of sample collection. Two valence states of inorganic iodine, I - and IO 3 - , were determined separately using the CE-ICP-MS system with a standard capillary column (150 μm inner φ, 75 cm length) with 30 kV as the extraction voltage. Buffer solution of 5 mM TRIS-HNO 3 (pH 3.0) was used for mobile phase. The method was applied to lake and river water samples collected at Rokkasho. Results indicated that the chemical form of inorganic iodine in all samples was IO 3 - . Additional lake water samples were collected from Lake O-ike-higashi-ko in the Juni

Radioactive contamination of plants in Japan covered with rainout from H-bomb detonations in March-May 1954 at Bikini Atoll, Marshall Island. Part II. Radioactive elements of contaminated plants

Energy Technology Data Exchange (ETDEWEB)

Yatazawa, M

1955-01-01

Following a fallout estimated at 0.2 microcurie/l, Trifolium repens, Astragalus sinicus, and Rumex japonicus were harvested and analyzed for radioactivity. Most of the radioactivity (2300 to 4700 counts/min/50 g plant ash) was associated with oxalate precipitate. A small amount of activity in the Zn group is attributed to /sup 65/Zn produced by reaction /sup 64/Zn (n,..gamma..) from Zn employed in the mechanical parts of the bomb. Sr-Ba radioactivity was 0.1 that of the rare earth group. Distribution of the radioactive elements was nearly the same as that found on the No. 5 Fukuryu-Maru.

On-stream chemical element monitor

International Nuclear Information System (INIS)

Averitt, O.R.; Dorsch, R.R.

1979-01-01

An apparatus and method for on-stream chemical element monitoring are described wherein a multiplicity of sample streams are flowed continuously through individual analytical cells and fluorescence analyses are performed on the sample streams in sequence, together with a method of controlling the time duration of each analysis as a function of the concomitant radiation exposure of a preselected perforate reference material interposed in the sample-radiation source path

The chemical behavior of the transuranic elements and the barrier function in natural aquifer systems

International Nuclear Information System (INIS)

Jewett, J.R.

1997-01-01

In a geological repository for long-lived radioactive wastes, such as actinides and certain fission products, most of the stored radionuclides remain immobile in the particular geological formation. If any of these could possibly become mobile, only trace concentrations of a few radionuclides would result. Nevertheless, with an inventory in the repository of many tonnes of transuranic elements, the amounts that could disperse cannot be neglected. A critical assessment of the chemical behavior of these nuclides, especially their migration properties in the aquifer system around the repository site, is mandatory for analysis of the long-term safety. The chemistry requited for this includes many geochemical multicomponent reactions that are so far only partially understood and hich therefore can be quantified only incompletely. A few of these reactions have been discussed in this paper based on present knowledge. If a comprehensive discussion of the subject is impossible because of this ack of information then an attempt to emphasize the importance of the predominant geochemical reactions of the transuranic elements in various aquifer systems should be made

Radioactive and chemical contamination of the water resources in the former uranium mining and milling sites of Mailuu Suu (Kyrgyzstan).

Science.gov (United States)

Corcho Alvarado, J A; Balsiger, B; Röllin, S; Jakob, A; Burger, M

2014-12-01

An assessment of the radioactive and chemical contamination of the water resources at the former uranium mines and processing sites of Mailuu-Suu, in Kyrgyzstan, was carried out. A large number of water samples were collected from the drinking water distribution system (DWDS), rivers, shallow aquifers and drainage water from the mine tailings. Radionuclides and trace metal contents in water from the DWDS were low in general, but were extremely high for Fe, Al and Mn. These elements were associated with the particle fractions in the water and strongly correlated with high turbidity levels. Overall, these results suggest that water from the DWDS does not represent a serious radiological hazard to the Mailuu Suu population. However, due to the high turbidities and contents of some elements, this water is not good quality drinking water. Water from artesian and dug wells were characterized by elevated levels of U (up to 10 μg/L) and some trace elements (e.g. As, Se, Cr, V and F) and anions (e.g. Cl(-), NO3(-), SO4(2-)). In two artesian wells, the WHO guideline value of 10 μg/L for As in water was exceeded. As the artesian wells are used as a source of drinking water by a large number of households, special care should be taken in order to stay within the WHO recommended guidelines. Drainage water from the mine tailings was as expected highly contaminated with many chemicals (e.g. As) and radioactive contaminants (e.g. U). The concentrations of U were more than 200 times the WHO guideline value of 30 μg/L for U in drinking water. A large variation in (234)U/(238)U isotopic ratios in water was observed, with values near equilibrium at the mine tailings and far from equilibrium outside this area (reaching ratios of 2.3 in the artesian well). This result highlights the potential use of this ratio as an indicator of the origin of U contamination in Mailuu Suu. Copyright © 2014 Elsevier Ltd. All rights reserved.

Remote detection and ecological monitoring of the industrial and natural nuclei activity of radioactive elements based on passive microwave radiometry

Science.gov (United States)

Chistyakova, Liliya K.; Chistyakov, Vyacheslav Y.; Losev, Dmitry V.; Penin, Sergei T.; Tarabrin, Yurij K.; Yakubov, Vladimir P.; Yurjev, Igor A.

1998-12-01

The passive remote method of microwave radiometry and its instrumental realization for express diagnostics of radioactive elements in the atmosphere have been discussed. Analysis of the microwave radiation due to ionization and dissociation of atmospheric components interacting with radioactive elements is carried out. The photochemical processes resulting in background microwave radiation power have been discussed. As an example, the results of natural experiment of detecting the atomic hydrogen radiation in the plume of emissions of nuclear cycle processing plants have been presented.

Cumulative and competitive effects of chemical elements on nuclear glass alteration

International Nuclear Information System (INIS)

Arena, Helene

2016-01-01

This work takes place in the context of the long-term behavior of nuclear glasses under repository conditions. The main objective is to identify, understand and compare the effects of some chemical elements present in the glass composition and/or in the repository media (Zn, Mg, Ni, Co, Fe, Ca, Gd, Ce, K, Cs, Cr and Ag) on the processes involved in glass alteration by water. The cumulative or competitive nature of the effects of these chemical elements was determined. To reach this goal, a 6 oxides simple glass (ISG) has been altered for more than 500 days in a solution containing one or more of the chemical elements of interest. The results indicate that Zn, Mg, Ni, Co and Fe elements increase glass alteration forming secondary phases with the same structure and stoichiometry (tri-octahedral smectites). To form, these silicates consume chemical elements (Si, Al) from the environment and induce a pH decrease until a limiting value of pH. Beyond this pH the precipitation of secondary phases is inhibited and these chemical elements can be integrated into the gel, replacing Ca whose solubility increases at lower pH. As long as they form secondary phases, the effects of these elements are cumulative. Rare earths Gd and Ce also increase glass alteration forming secondary phases but their effects are lower as they contain less silicon. These elements are not integrated in the gel. Chromium increases glass alteration by precipitating with Ca and leading to a less protective gel, depleted in Ca. Silver precipitates as AgCl and has no effect on the alteration of the glass. The chemical elements K, Cs and Ca limit glass alteration by integrating into the gel and slowing down the transport phenomena therein. This integration is competitive: the order of integration (quantity and effectiveness glass alteration limitation) is the following Ca≥≥Cs≥K. Thus, the increase of glass alteration may be proportional to the quantity of elements promoting the precipitation of

Chemical analogy in the case of hydrolysis species of F-elements

International Nuclear Information System (INIS)

Hirotake Moriyama; Hajimu Yamana; Kenso Fujiwara

2001-01-01

In spite of much importance, some of the thermodynamic data of actinide elements are still lacking, and the chemical behaviour of these elements is often predicted by considering chemical analogy, that is by taking the known data of the same and similar group elements. It is thus quite important to establish the basis and conditions for applying the chemical analogy. In the present study, some topics are discussed which are related with the chemical analogy for the hydrolysis behaviour of actinide ions. Systematic trends of the thermodynamic data of actinide ions, namely the solubility products and hydrolysis constants, are discussed by considering the results of recent measurements and by considering possible contributions of non-electrostatic interactions of actinide ions in addition to those of ordinary electrostatic ones. (authors)

Cluster analysis to evaluate stable chemical elements and physical-chemical parameters behavior on uranium mining waste

International Nuclear Information System (INIS)

Pereira, Wagner de Souza; Py Junior, Delcy de Azevedo; Goncalves, Simone; Kelecom, Alphonse; Morais, Gustavo Ferrari de; Campelo, Emanuele Lazzaretti Cordova; Dores, Luis Augusto de Carvalho Bresser

2011-01-01

The Ore Treating Unit (UTM, in portuguese) is a deactivated uranium mine. A cluster analysis was used to evaluate the behavior of stable chemical elements and physical-chemical parameters in their effluents. The utilization of the cluster analysis proved itself effective in the assessment, allowing the identification of groups of chemical elements, physical-chemical parameters and their joint analysis (elements and parameters). As a result we may assert, based on data analysis, that there is a strong link between calcium and magnesium and between aluminum and rare-earth oxides on UTM's effluents. Sulphate was also identified as strongly linked to total and dissolved solids, and those to electrical conductivity. There were other associations, but not so strongly linked. Further gathering, to seasonal evaluation, are required in order to confirm those analysis. Additional statistical analysis (factor analysis) must be used to try to identify the origin of the identified groups on this analysis. (author)

Cluster analysis to evaluate stable chemical elements and physical-chemical parameters behavior on uranium mining waste

Energy Technology Data Exchange (ETDEWEB)

Pereira, Wagner de Souza; Py Junior, Delcy de Azevedo; Goncalves, Simone, E-mail: wspereira@inb.gov.br [Unidade de Tratamento de Minerio (UTM/INB), Pocos de Caldas, MG (Brazil). Coordenacao de Protecao Radiologica. Grupo Multidisciplinar de Radioprotecao; Kelecom, Alphonse [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Biologia. Lab. de Radiobiologia e Radiometria Pedro Lopes dos Santos; Morais, Gustavo Ferrari de; Campelo, Emanuele Lazzaretti Cordova [Unidade de Tratamento de Minerio (UTM/INB), Pocos de Caldas, MG (Brazil). Coordenacao de Desenvolvimento de Processos; Dores, Luis Augusto de Carvalho Bresser [Unidade de Tratamento de Minerio (UTM/INB), Pocos de Caldas, MG (Brazil). Gerencia de Descomissionamento

2011-07-01

The Ore Treating Unit (UTM, in portuguese) is a deactivated uranium mine. A cluster analysis was used to evaluate the behavior of stable chemical elements and physical-chemical parameters in their effluents. The utilization of the cluster analysis proved itself effective in the assessment, allowing the identification of groups of chemical elements, physical-chemical parameters and their joint analysis (elements and parameters). As a result we may assert, based on data analysis, that there is a strong link between calcium and magnesium and between aluminum and rare-earth oxides on UTM's effluents. Sulphate was also identified as strongly linked to total and dissolved solids, and those to electrical conductivity. There were other associations, but not so strongly linked. Further gathering, to seasonal evaluation, are required in order to confirm those analysis. Additional statistical analysis (factor analysis) must be used to try to identify the origin of the identified groups on this analysis. (author)

Management of low and intermediate level radioactive wastes with regard to their chemical toxicity

International Nuclear Information System (INIS)

2002-12-01

A preliminary overview is provided of management options for low and intermediate level radioactive waste (LILW) with regard to its chemical toxicity. In particular, the following issues are identified and described associated with the management and safe disposal of chemically toxic materials in LILW: the origin and characteristics; the regulatory approaches; the pre-disposal management; the disposal; the safety assessment. Also included are: regulatory framework for chemically toxic low level wastes in the USA; pre-disposal processing options for LILW containing chemically toxic components; example treatment technologies for LILW containing chemically toxic components and safety assessment case studies for Germany, Belgium, France and Sweden

Curie's hypotheses concerning radioactivity and the origin of the elements

International Nuclear Information System (INIS)

Kuroda, P.K.

1999-01-01

Pierre Curie gave two hypotheses at first; (1) It can be supposed that the radioactive substances borrow the energy, which they release, from an external radiation, and their radiation would then be a secondary radiation, (2) It can be supposed that the radioactive substances draw from themselves the energy which they release. The second hypothesis has shown the more fertile in explaining the properties of the radioactive substances. Consequently, the first hypothesis became more or less forgotten. It appears, however, the first hypothesis should play an important role in explaining the phenomena concerning the origin of the elements. The Oklo Phenomenon has demonstrated that a nuclear fire had once existed on our planet earth and formation of heavy elements was occurring in nature. The author pointed out that the difference in the isotopic compositions of xenon found in meteorites, lunar samples and in the earth's atmosphere can only be explained as due to the alterations of the isotropic compositions of xenon by combined effect of (a) mass-fractionation, (b) spallation, and (c) stellar temperature neutron-capture reactions. The strange xenon components are not isotopically pure substance. Instead, xenon-HL is a mixture of the 244 Pu fission xenon and the xenon whose isotopic compositions is severely altered by a combined effect of the processes (a), (b) and (c) mentioned above. These results also indicate that C1 carbonaceous chondrites, which is generally as the most primitive sample of the solar system material, began to retain its xenon 5.1 billion years ago, when the plutonium to uranium ratio in the solar system was as high as almost 0.6 (atom/atom), while the C2 carbonaceous chondrite began to retain their xenon about 150 million years later and the ordinary chondrites and achondrite about 500 to 600 million years later. This means that the birth of the solar system began soon after the last supernova exploded about 5.1 billion years ago, and the generally

Chemical elements in egg shell of a commercial strain of domestic ...

African Journals Online (AJOL)

A study was conducted to determine the chemical elements of the egg shell of exotic commercial pullets (Lohmann) in their first laying year. A total of 160 eggs from eighty pullets were randomly selected at three-monthly intervals during the production year for the ddermination of chemical elements or the eggshell.

Use of a New Method Involving Labelling with Non-Radioactive Elements and Activation Analysis to Investigate Wear

International Nuclear Information System (INIS)

Radvan, M.; Reven'ska-Kos'tsjuk, B.; Vez'ranovski, E

1967-01-01

In view of the considerable difficulties in using the labelled-atom method to investigate the wear of bearings in agricultural machines under operating conditions, and also to investigate the wear of fire-proof materials in steel production (owing to the occurrence of exogenous non-metallic inclusions), the authors turned their attention to labelling these parts with nonradioactive elements, which were then determined by activation analysis. In the work carried out by this method either mixtures of rare-earth oxides or lanthanum oxide alone were used as tracers, because of their useful nuclear properties. The use of rare-earth elements is also justified by the fact that their chemical properties differ from those of the remaining elements in the material investigated, which means that they can be separated from the respective carriers. In investigations of the wear of agricultural machine bearings made from cast-iron modified with rare-earth elements in an amount too low to cause structural changes, the authors used the modifier as a tracer. The wear of polyamide bearings was also investigated. The use of activation analysis is particularly interesting in this case, since certain properties of the polyamide make standard methods of investigation completely impossible. The products of wear were separated from the oil or grease by extraction or combustion. In determinations of non-metallic exogenous inclusions in ball-bearing steel, caused by certain fireproof materials, the wear of these materials was investigated using modem steel production technology. The aim of these investigations was to determine the effect of vacuum extraction and the use of induction mixers on the passage of fire-resistant particles into the steel. A method of determination was developed based on chemical separation of the tracer after activation with an appropriate surplus of non-radioactive carrier, and also a method of separating it before activation with a calcium carrier. The authors

Effect of chemical structure on the radioactive decay rate of 71Ge

International Nuclear Information System (INIS)

Makariunas, K.; Makariuniene, E.; Dragunas, A.

1979-01-01

The influence of the chemical structure on the electron capture radioactive decay rate of 71 Ge was observed. 71 Ge nuclei in bivalent sulphide GeS decay faster than in quadrivalent sulphide GeS 2 . The relative change Δlambda/lambda of the decay constant lambda is + (11.4 +- 1.7) X 10 -4 . A possibility to use the experimental values of Δlambda/lambda to determine the chemical changes in the electron density at germanium nuclei in germanium chemical compounds is discussed. Quantitative determination of the changes in the electron density is complicated because of insufficient reliability of the published values of exchange and overlap corrections to the electron capture probabilities. (Auth.)

Physical--chemical studies of transuranium elements. Progress report, April 1, 1977--March 31, 1978

International Nuclear Information System (INIS)

Peterson, J.R.

1978-01-01

Major advances in our continuing program to determine, interpret, and correlate the basic chemical and physical properties of the transuranium elements are summarized for the period April 1, 1977, through March 31, 1978. CfCl 2 , EsCl 2 , EsBr 2 , and EsI 2 were synthesized and characterized spectrophotometrically, as were several mixed-valence lanthanide-actinide halides (e.g., GdCf 4 Cl 11 ) and CmF 4 , CfF 4 , and EsF 3 . All samples not containing einsteinium were also examined by X rays. Studies of the chemical consequences of the radioactive decay series 253 Es alpha decaying to 249 Bk beta decaying to 249 Cf have continued and expanded. Elemental Cm-248 has been prepared on the one-half milligram scale and used to synthesize CmP and CmSb. Single crystals of AmTe 2 and AmSe 2 have been grown from a Te melt and by iodine transport, respectively. Our SQUID magnetometer was tested successfully in a preliminary configuration, and the expected sensitivity of the device was confirmed. A new design for the flux sensing coils was incorporated prior to an apparatus calibration experiment with lead. A porous vitreous carbon material was found to make a useful optically transparent electrode for simultaneous electrochemical and absorption spectroscopic investigations. Cyclic voltammograms of UO 2 2+ were obtained prior to a spectroelectrochemical study of the radiation of UO 2 2+ . The major obstacle in our solution microcalorimetry program was overcome by the realization of a leak-free sample container. Calorimeter performance now warrants experiments with transuranium element samples. The electrochemical reductions of Cf(III) and Es(III) have been studied by polarography and/or cyclic voltammetry. The results suggest that both are reduced to the divalent state before being reduced to the amalgam

Recommendations for sampling for prevention of hazards in civil defense. On analytics of chemical, biological and radioactive contaminations. Brief instruction for the CBRN (chemical, biological, radioactive, nuclear) sampling; Empfehlungen fuer die Probenahme zur Gefahrenabwehr im Bevoelkerungsschutz. Zur Analytik von chemischen, biologischen und radioaktiven Kontaminationen. Kurzanleitung fuer die CBRN-Probenahme

Energy Technology Data Exchange (ETDEWEB)

Bachmann, Udo; Biederbick, Walter; Derakshani, Nahid (and others)

2010-07-01

The recommendation for sampling for prevention of hazards in civil defense is describing the analytics of chemical, biological and radioactive contaminations and includes detail information on the sampling, protocol preparation and documentation procedures. The volume includes a separate brief instruction for the CBRN (chemical, biological, radioactive, nuclear) sampling.

Determination of Heavy Metals and Radioactive Elements in Alluvial Soil using Atomic Absorption and Gamma Spectroscopy

International Nuclear Information System (INIS)

Hamed, S.S.; Walley EI Dine, N.; Soliman, S.I.; Moussa, W.M.

2008-01-01

The paper describes some methods dealing with measurements of some heavy and radioactive elements (U, Th and K) in Egyptian cultivated soil samples. Samples were collected from Toshka area. Also, soil and plant samples were collected from Kalube and EI - Gabal EI - Asfar to compare the obtained results from both region. Flame atomic absorption spectrometry (FAAS),Neutron activation analysis (INAA) and Natural radioactivity techniques were followed. FAAS and INAA techniques agreed fairly well for the compared elements Co,Zn and Fe which determined by the two techniques. Also for K which was determined by FAAS and natural radioactivity. It was found that the concentration range in soil samples for Co, Fe, K and Zn lies between 4.18 and 29.2 μg/g, 3.0 and 3.8 mg/g, 3.49 and 13.28 mg/g and 120 and 663 μg/g respectively while in plant samples the concentration of Co was from 3.02 to 4.02 μg/g, Fe from 1.18 to 1.35 mg/g and Zn from 29.63 to 73.02 μg/g

Comparison of the thermodynamic databases for radioactive elements in application to the calculation of the solubilities in the porewater

International Nuclear Information System (INIS)

Doi, Reisuke; Shibata, Masahiro

2006-07-01

To calculate the solubility of radioactive elements which is the important parameter for performance assessment of geological disposal system, the thermodynamic database must be reliable and based on the latest information. In this research, it has been compared in the calculation of the solubilities of the representative radioactive elements in the porewater compositions of the compacted bentonite which were set up in the second progress report (H12) that the thermodynamic database of JNC, OECD/NEA, Nagra/PSI. And the causes of the differences among the results from application of different databases were investigated and discussed. (author)

Apparatus for the storage of transport- and storage-containers containing radioactive fuel elements

International Nuclear Information System (INIS)

Vox, A.

1983-01-01

The invention concerns an apparatus for the storage of transport and storage containers containing radioactive fuel elements. For each transport or storage container there is a separate silo-type container of steel, concrete, prestressed concrete or suchlike breakproof and fireproof material, to be placed in the open, that can be opened for removal and placing of the transport or storage container respectively. (orig.) [de

Geochemistry of radioactive elements in the process of weathering of carbonatites, acidic and alkali rocks

International Nuclear Information System (INIS)

Zhmodik, S.M.

1984-01-01

Geochemical peculiarities of uranium and thorium behaviour under formation of area crusts of weathering of granitoids, alkali rocks and carbonatites of certain areas of East Siberia are considered. The presented crysts of weathering have been formed under different climatic conditions, they have different age (in the limit of upper Cretaceous period - Neogene up to Quaternary time), chemical and mineral composition. Factors determining and controlling the level of uranium and thorium concentrations in weathering products are disclosed on the basis of facts using the methods of neutron-fragmentary radiography and by-fractional balances. Uranium and thorium distribution in granulometric fractions of crysts of weathering is considered in detail. Data on change in forms of radioactive elements under weathering, effect of fine-dispersed hypergene minerals (kaolinite, montmorillonite, goethite, etc.) on the character of uranium and thorium distribution in eluvial products as well as on sources of migrating uranium in crusts of weathering are presented. Scales of uranium and thorium redistribution under weathering are revealed. Supposition on the source of uranium and throium in sediments is made

Production of chemically reactive radioactive ion beams through on-line separation

International Nuclear Information System (INIS)

Joinet, A.

2003-10-01

The ISOL (isotope separation on line) allows the production of secondary radioactive ion beams through spallation or fragmentation or fission reactions that take place in a thick target bombarded by a high intensity primary beam. The challenge is to increase the intensity and purity of the radioactive beam. The optimization of the system target/source requires the right choice of material for the target by taking into account the stability of the material, its reactivity and the ionization method used. The target is an essential part of the system because radioactive elements are generated in it and are released more or less quickly. Tests have been made in order to select the best fitted material for the release of S, Se, Te, Ge and Sn. Materials tested as target filling are: ZrO 2 , Nb, Ti, V,TiO 2 , CeO x , ThO 2 , C, ZrC 4 and VC). Other molecules such as: COSe, COS, SeS, COTe, GeS, SiS, SnS have been studied to ease the extraction of recoil nuclei (Se, S, Te, Ge and Sn) produced inside the target

Chemistry of the heaviest elements

International Nuclear Information System (INIS)

Hoffman, D.C.

1996-01-01

Studies of the chemical properties of the elements at the uppermost end of the periodic table are discussed. Some historical perspective is given, but major emphasis is on recent studies. Isotopes of these elements are short-lived and, therefore, must be studied near the site of production. They must be produced with charged-particle beams at accelerators rather than via neutron capture. The use of radioactive heavy actinide targets is often required and the number of atoms produced is so small that any chemistry to be performed must be done on an ''atom-at-a-time'' basis. Furthermore, a knowledge of their nuclear properties is required in order to identify and detect them. To date, both gas and aqueous phase properties of elements as heavy as element 104 (rutherfordium) and element 105 (hahnium) have been investigated, even though their longest-lived known isotopes have half-lives of only 65 and 35 seconds, respectively. The experimental results show that their chemical properties cannot be simply extrapolated from the known properties of their lighter homologs in the periodic table, emphasizing the importance of obtaining additional experimental information for the heaviest elements to compare with predictions and help assess the influence of relativistic effects. The feasibility of the extension of chemical studies to still heavier elements is also discussed. (orig.)

An Alternate Graphical Representation of Periodic table of Chemical Elements

OpenAIRE

Abubakr, Mohd

2009-01-01

Periodic table of chemical elements symbolizes an elegant graphical representation of symmetry at atomic level and provides an overview on arrangement of electrons. It started merely as tabular representation of chemical elements, later got strengthened with quantum mechanical description of atomic structure and recent studies have revealed that periodic table can be formulated using SO(4,2)* SU(2) group. IUPAC, the governing body in Chemistry, doesn't approve any periodic table as a standard...

Analytical determination of traced elements in concrete samples used in nuclear reactors of the European Community

International Nuclear Information System (INIS)

May, S.; Piccot, D.

1984-01-01

In reactor dismantling residual radioacting of concrete used, especially in biological shield can brought problems for treatment and disposal. Radioactivity of concrete from reactors can be forecasted if element content is known. Elements producing long life radionuclides are: chlorine, calcium nickel, cobalt, niobium, europium and samarium. Neutron activation analysis is used for determination of these elements whithout chemical separation for Ca, Co, Eu and Sm and with radiochemical separation for Cl, Ni and Nb. A lot of elements, less interesting are also determined by gamma spectrometry after irradiation. It was possible to determine 29 elements in 21 concrete samples from different European Community reactors

Geochemical mapping of radioactive elements using helicopter-borne gamma-ray spectrometry (Tiouit, Eastern Anti-Atlas, Morocco): Or occurrence and environmental impact

Science.gov (United States)

Miftah, Abdelhalim; El Azzab, Driss; Attou, Ahmed; Manar, Ahmed; Rachid, Ahmed; Ramhy, Haytam

2018-03-01

The spectrometric prospection is a direct geophysical method based on the analysis of the radioactive elements spectra, due to three principal radioactive elements 40K, 238U and 232Th. In order to measure the content of radioactive elements a geophysical helicopter survey was carried out to a flight altitude of 60 m from the subsoil, covering the geological map of Tiouit 1/50,000 with an extent of 45.5 × 29 km2. In this paper, we propose an application in the environment and or occurrence by the production of maps concentration in K, U and Th to delimit the areas with purely natural radioactive risk by the calculation of the dose rate in mSv, the found values show a variation of 0,3 with 1649 mSv with a median value of 0,831 mSv. Moreover, data processing as the horizontal gradient filter which allowed to amplify the spectrometric signatures, this one coupled to the upward continuation, lead us to a better location of the abrupt changes, which materialize by spectrometric lineaments, reflecting the change of the geochemical properties of the basement.

The study on radioactivity reduction of spent PWR cladding hull

International Nuclear Information System (INIS)

Jung, I. H.; Kim, J. H.; Park, C. J.; Jung, Y. H.; Song, K. C.; Lee, J. W.; Park, J. J.; Yang, M. S.

2003-01-01

Hull arising from the spent PWR fuel elements is classified as a high-level radioactive waste. This report describes the radio-chemical characteristics of the hull-from PWR spent fuel of 32,000MWd/tU burn-up and 15 years cooling, discharged from Gori Unit I cycled 4-7-by examination and literature survey. On the basis of the results, a method of degradation to middle and low-level radioactive waste was proposed by dry process such as laser or plasma technique with removing the nuclides deposited on the surface of the hull

Correlation study of chemical elements in phosphate ores

International Nuclear Information System (INIS)

Braganca, Maura Julia Camara da Silva

1999-07-01

Geological phenomena, 1) endogenous (volcanism, magmatic flow, metasomatism); 2) metamorphic (resultant of action of high temperature and pressure) and; 3) exogenous (intemperism, contamination) can modify the chemical composition of rocks soils. Thus, chemical elements with little mobility can be used as indicators of the previous geological situation before the occurrence of these phenomena and can sign the chemical composition of the initial formation. The elements with great mobility can already be used as indicators of the characteristic and intensity of the changes, can point out the influence factors and its space and time conditions. In this work the results of the study of phosphated samples ores coming from two alkaline-carbonatitic chimneys (Araxa and Catalao) and from a meta sedimentary rock (Patos de Minas), located phosphate rock deposit, are presented. The results were obtained using the instrumental neutron activation analysis, inductively coupled plasma-mass spectrometry (ICP-MS) and ICP-AES techniques. A comparison of the three types of samples ores, using chemical, crystallographic and statistical methods, shows that the Araxa and Catalao present some geochemical similarities and they are distinguished of Patos de Minas, despite its geographic proximity. (author)

Study about the integrated treatment of chemical and radioactive effluents, introducing the zero release concept

International Nuclear Information System (INIS)

Mierzwa, Jose Carlos

1996-01-01

An Integrated System to the treatment of Chemical and Radioactive Effluents to the Centro Experimental Aramar is proposed and evaluated, introducing the Effluent Zero Release concept, where factors related to the environmental regulation in vigor in the country, as well as the availability of hydrological resources in the place where CEA have been implanted, are considered. Through a literature analysis of the main effluents treatment techniques available nowadays and after a case of study selection, take into account two industrial installations that will be implanted at CEA, it was defined an arrangement to compose the Integrated System to the Treatment of Chemicals and Radioactive Effluents, focusing the Zero Release concept consolidation. A defined arrangement uses a combination among three treatment processes, it means chemical precipitation, reverse osmosis and evaporation, that were experimentally evaluated. The proposed arrangement was evaluated using synthetic effluents, that were prepared based on data from literature and conception documents of the installation considered in this work. Three kinds of effluents were simulated, one arising from a nuclear reactor laundry, one arising from the water refrigeration system and demineralized water production to the nuclear reactor and the other one arising from a nuclear material production laboratory. Each effluent were individually submitted to the selected treatment processes, to get the best operational conditions for each treatment process. The results got during the laboratory assays show that the proposed Integrated System to the Treatment of Chemicals and Radioactive Effluents is feasible, consolidating the Effluent Zero Release concept, which is the proposition of this work. (author)

Purposeful synthesis of chemical elements and ecologically pure mobile sources of energy

International Nuclear Information System (INIS)

Krivitsky, V. A.; Gareev, F. A.

2007-01-01

It is well known [1] that the natural geo-transmutation of chemical elements occurs in the atmosphere and earth in the regions of a strong change in geo-, bio-, acoustic-, and electromagnetic fields. The mineral row materials contain the same accompanying chemical combinations which are independent of mineral deposit [2]. This means that the formation of chemical elements occurs in the same physical and chemical conditions. These conditions were simulated on the fundamental cooperative resonance synchronization principle [1]. The experimental facility was constructed on the basis of our model which provided with the calculated final chemical elements. These experimental results indicate new possibilities for, simulating, inducing and controlling nuclear reactions by low energy external fields. The borrowing from the geo-transmutation mechanisms of chemical elements creates the fundamental directions in low energy nuclear reaction researches for construction of new ecologically pure mobile sources of energy independent of oil, gas and coal, new substances, and technologies. References [1] F.A. Gareev, I.E. Zhidkova, E-print arXiv Nucl-th/0610002 2006. [2] V.A. Krivzskii, Transmutazija ximicheskix elementov v evolyuzii Semli (in Russian), Moscow 2003

Advanced chemical analysis service for elements, radionuclides and phases

International Nuclear Information System (INIS)

Sansoni, B.

1986-01-01

A review is given on the structure, organisation and performance of the chemical analysis service of the Central Department for Chemical Analysis at the Kernforschungsanlage Juelich GmbH. The research and development programs together with the infrastructure of the Centre afford to analyse almost all stable elements of the periodical table in almost any material. The corresponding chemical analysis service has been organized according to a new modular system of analytical steps. According to this, the most complicated and, therefore, most general case of an analytical scheme for element and radionuclide analysis in any type of material can be differentiated into about 14 different steps, the modules. They are more or less independent of the special problem. The laboratory is designed and organized according to these steps. (orig./PW) [de

Geochemistry of radioactive waste disposal

International Nuclear Information System (INIS)

Bird, G.W.

1979-01-01

Safe, permanent disposal of radioactive wastes requires isolation of a number of elements including Se, Tc, I, Sr, Cs, Pd, u, Np, Pu and Cm from the environment for a long period of time. The aquatic chemistry of these elements ranges from simple anionic (I - ,IO 3 - ) and cationic (Cs + ,Sr ++ ) forms to multivalent hydrolyzed complexes which can be anionic or cationic (Pu(OH) 2 + ,Pu(OH) 3 + , PuO 2 (CO 3 )(OH) - ,PuO 2 Cl - ,etc.) depending on the chemical environment. The parameters which can affect repository safety are rate of access and composition of grounwater, stability of the waste container, stability of the waste form, rock-water-waste interactons, and dilution and dispersion as the waste moves away from the repository site. Our overall research program on radioactive waste disposal includes corrosion studies of containment systems hydrothermal stability of various waste forms, and geochemical behaviour of various nuclides including solubilities, redox equilibria, hydrolysis, colloid fomation and transport ion exchange equilibria and adsorption on mineral surfaces and irreversible precipitation reactions. This paper discusses the geochemistry of I, Se, Tc, Cs, Sr and the actinide elements and potential mechanisms by which the mobility could be retarded if necessary

Chemical mode control in nuclear power plant decommissioning during operation of technologies in individual radioactive waste processing plants

International Nuclear Information System (INIS)

Horvath, J.; Dugovic, L.

1999-01-01

Sewage treatment of nuclear power plant decommissioning is performed by system of sewage concentration in evaporator with formation of condensed rest, it means radioactive waste concentrate and breeding steam. During sewage treatment plant operation department of chemical mode performs chemical and radiochemical analysis of sewage set for treatment, chemical and radiochemical analysis of breeding steam condensate which is after final cleaning on ionization filter and fulfilling the limiting conditions released to environment; chemical and radiochemical analysis of heating steam condensate which is also after fulfilling the limiting conditions released to environment. Condensed radioactive concentrate is stored in stainless tanks and later converted into easy transportable and chemically stable matrix from the long term storage point of view in republic storage Mochovce. The article also refer to bituminous plant, vitrification plant, swimming pool decontamination plant of long term storage and operation of waste processing plant Bohunice

Study of chemically synthesized ZnO nano particles under a bio template using radioactive ion beam

CERN Multimedia

This is a project proposal to study nano sized semiconductor ZnO system, useful in biology and medicinal purposes, using radioactive ion beam from ISOLDE. Doping of the nano particles with Cu, Cd and Ga ions (in their variable valancy states) are expected to impart changes in the electrical structure and properties in the said system under study. The morphological changes, chemical environment, micro structure, electrical and optical properties of the nano size particles of ZnO system (developed under a bio template of folic acid) after the interaction with radioactive ion beam will be studied. The provision of perturbed angular correlation (PAC) study with respect to the changes in chemical environment, where ever possible will be attempted.

Radioactive waste disposal

International Nuclear Information System (INIS)

Cluchet, J.; Roger, B.

1975-10-01

After mentioning the importance of the problem of the disposal of wastes produced in the electro-nuclear industry, a short reminder on a few laws of radioactivity (nature and energy of radiations, half-life) and on some basic dosimetry is given. The conditioning and storage procedures are then indicated for solid wastes. The more active fractions of liquid wastes are incorporated into blocks of glass, whereas the less active are first concentrated by chemical treatments or by evaporation. The concentrates are then embedded into concrete, asphalt or resins. Storage is done according to the nature of each type of wastes: on a hard-surfaced area or inside concrete-lined trenches for the lowest radioactivity, in pits for the others. Transuranium elements with very long half-lives are buried in very deep natural cavities which can shelter them for centuries. From the investigations conducted so far and from the experience already gained, it can be concluded that safe solutions are within our reach [fr

The use of ceramic membranes for radioactive solutions purification

International Nuclear Information System (INIS)

Zakrzewska-Trznadel, G.

2002-01-01

Membrane permeation combined with complexation was tested for radioactive wastes processing purpose. The results of experiments with MEMBRALOX and CeRAM INSIDE filtering elements are presented in the paper. The pore size of ceramic membranes was in 1kD-100 nm range. The experiments were performed with non-active and with radioactive model solutions and original radioactive waste samples. To achieve high decontamination factors the process was enhanced by chemical complexation. Such complexants as poly(acrylic) acid and polyacrylic)acid salts of different crosslinking, polyethylenimine and cyanoferrates were tested. The experiments showed the significant increase of retention and decontamination factors while before ultrafiltration macromolecular ligands were added. The effectiveness of complexation by each ligand is strongly dependent on pH and alkali metals concentration. (author)

The effect of storage on Physical, Chemical and Bacteriological ...

African Journals Online (AJOL)

ADOWIE PERE

Ten (10) different companies' water samples each of bottled water (B) and ... after storage as with other chemical element except that lead showed ... Although it is true that soil generally ... organic pollutants, heavy metals and radioactive.

Chemical behaviour of zinc in cover gas environments

International Nuclear Information System (INIS)

Thorley, A.W; Blundell, A.; Lloyd, R.

1987-01-01

The possibility that enhancement of 65-Zn in the cover gas regions of reactor plant may increase levels of radioactivity and provide potential embrittlement situations has lead to a limited metallurgical and chemical investigation into how this element behaves in cover gas environments. This paper reports the chemical findings from those investigations and compare results obtained with those anticipated from thermodynamic predictions

Radioactive waste today - an asset tomorrow

Energy Technology Data Exchange (ETDEWEB)

Holmstrand, M. [Norwegian Radiation Protection Authority (Norway)

2014-07-01

Mining of Rare Earth Elements (REE) causes radioactive pollution, as ores which contain REE also contain an elevated concentration of naturally occurring radioactive materials (NORM). Wastes from REE mining are therefore regarded as being inherently radioactive. One of the potential economically viable REE resources in Norway is in the Fensfield area in Telemark County, which is recognized as one of the world's largest thorium resources. If REE was mined in this area, a large volume of radioactive waste would be created. The authorities would then need to know how to regulate the waste so that the environmental impact would be as low as reasonably achievable when societal and economic factors having been accounted for (ALARA). Radioactive pollution from REE tailings could be a threat to the environment, biota and humans. However, naturally occurring thorium is practically not mobile nor bioavailable and has a relatively low specific activity and might therefore safely be deposited in a landfill. An environmental risk assessment should be used to evaluate if it is justifiable to deposit the radioactive tailings in a landfill or if alternative ways of handling, such as extraction of thorium in addition to extraction of REE from the ore, might be better. The risk assessment must start with a source term, the native carbonatite rocks, and an investigation on how the chemical properties of the rock changes when it's milled and treated with chemicals. Changes in the physical and chemical properties and changes in the environment where the processed rock are deposited might mobilize and/or make thorium bioavailable, thus increasing the environmental risk. Removal of thorium from the raw materials or tailings from the REE mining industry prior to deposition could be seen as one form of environmental protection with many benefits, for instance reducing the potential of external and internal radiation in biota and humans. We could also speculate about the

Radioactive liquid waste processing system

International Nuclear Information System (INIS)

Noda, Tetsuya; Kuramitsu, Kiminori; Ishii, Tomoharu.

1997-01-01

The present invention provides a system for processing radioactive liquid wastes containing laundry liquid wastes, shower drains or radioactive liquid wastes containing chemical oxygen demand (COD) ingredients and oil content generated from a nuclear power plant. Namely, a collecting tank collects radioactive liquid wastes. A filtering device is connected to the exit of the collective tank. A sump tank is connected to the exit of the filtering device. A powdery active carbon supplying device is connected to the collecting tank. A chemical fluid tank is connected to the collecting tank and the filtering device by way of chemical fluid injection lines. Backwarding pipelines connect a filtered water flowing exit of the filtering device and the collecting tank. The chemical solution is stored in the chemical solution tank. Then, radioactive materials in radioactive liquid wastes generated from a nuclear power plant are removed by the filtering device. The water quality standard specified in environmental influence reports can be satisfied. In the filtering device, when the filtering flow rate is reduced, the chemical fluid is supplied from the chemical fluid tank to the filtering device to recover the filtering flow rate. (I.S.)

Radioactive indium labelling of the figured elements of blood. Method, results, applications

International Nuclear Information System (INIS)

Ducassou, D.; Nouel, J.P.

Following the work of Thakur et al. the authors became interested in red corpuscle, leucocyte and platelet labelling with indium 111 or 113m (8 hydroxyquinolein-indium). For easier labelling of the figured elements of blood the technique described was modified. The chelate is prepared by simple contact at room temperature of indium 111 or 113m chloride and water-soluble 8 hydroxyquinolein sulphate, in the presence of 0.2M TRIS buffer. The figured element chosen suspended in physiological serum is added directly to the solution obtained, the platelets and leucocytes being separated out beforehand by differential centrifugation. While it gives results similar to those of Thabur et al. the method proposed avoids the chloroform extraction of the radioactive chelate and the use of alcohol, liable to impair the platelet regation capacity [fr

Chemical aspects of nuclear waste treatment

International Nuclear Information System (INIS)

Bond, W.D.

1980-01-01

The chemical aspects of the treatment of gaseous, liquid, and solid wastes are discussed in overview. The role of chemistry and the chemical reactions in waste treatment are emphasized. Waste treatment methods encompass the chemistry of radioactive elements from every group of the periodic table. In most streams, the radioactive elements are present in relatively low concentrations and are often associated with moderately large amounts of process reagents, or materials. In general, it is desirable that waste treatment methods are based on chemistry that is selective for the concentration of radionuclides and does not require the addition of reagents that contribute significantly to the volume of the treated waste. Solvent extraction, ion exchange, and sorbent chemistry play a major role in waste treatment because of the high selectivity provided for many radionuclides. This paper deals with the chemistry of the onsite treatment methods that is typically used at nuclear installations and is not concerned with the chemistry of the various alternative materials proposed for long-term storage of nuclear wastes. The chemical aspects are discussed from a generic point of view in which the chemistry of important radionuclides is emphasized

Identification of radioactive minerals by means of X-rays

International Nuclear Information System (INIS)

Toubes, R.O.

1982-05-01

As a result of a thorough revision of the extensive bibliography from different sources avialable to the author, an updated compilation (up to December, 31st., 1981) was made of the fundamental parameters for the identification, by means of X-rays, of the radioactive minerals and of those which can behave as such as a consequence of an eventual incorporation of radioactive chemical elements. The data is arranged in 3 sections: the first one is an Entry Register which, on the basis of the five strongest lines or the dia-gram, allows to readily find out the species whose main X-rays spacings are closest to those of the samples being identified. In the second section, the species are listed in alphabetical order, together with their corresponding X-ray spacings and a description of their mineralogical, chemical and physical characteristics, as well as any other useful data to facilitate correct identification of the samples. The third and last section is a catalogue of the radioactive minerals grouped according to their annions. (C.A.K.) [es

GLOBAL AND REGIONAL GEOCHEMICAL INDEXES OF PRODUCTION OF CHEMICAL ELEMENTS

Directory of Open Access Journals (Sweden)

Nikolay S. Kasimov

2014-01-01

Full Text Available This paper presents a geochemical assessment of the primary involvement of chemical elements in technogenesis in the world and individual countries. In order to compare the intensity of production of various chemical elements in different countries, the authors have introduced a number of new terms and parameters. The new term is “abstract rock” (AR - an elemental equivalent, whose average composition corresponds to the average chemical composition of the upper continental crust. The new parameters are: “conditional technophility of an element” (TY, “specific technophility” (TYN “regional conditional technophility” (TYR, “specific regional technophility” (TN, and “density of regional conditional technophility” (TS. TY equals to the tons of AR per year necessary for the production of the current level of the element. TY of different elements has been estimated for 2008-2010. The highest TY values are associated with C, S, N, Ra, and Au. TY of many micro- and ultramicroelements is of the order of n•1011t. TYN reflects the volume of AR per the world’s capita. TYN changes from the 1960s to 2010 indicates that the Earth’s population is growing much faster than its demand for many chemical elements. TYR, TN, and TS were used for the integrated assessment of technogenesis at the regional scale; they reflect the intensity of the technogenesis process at the level of individual countries and allow comparing countries with different levels of elements production, population, and areas. The TN and TS levels of the leaders in extraction of natural resources are below these values in other countries due to the large territories (Russia, USA, Canada, Australia, Saudi Arabia, Kazakhstan, Argentina, Bolivia, Venezuela, Colombia, Zambia, Mali, Libya, Mongolia, and Sudan, to the large population (Indonesia, Vietnam, the Philippines, Bangladesh, Nigeria, or to both high spatial and demographic dimensions (India, Brazil, France, Egypt

Metrological system for y-ray spectrometry measurement of the specific activity and mass fraction of natural radioactive elements in soil and rock samples

International Nuclear Information System (INIS)

Khaikovich, I.M.; Fominykh, V.I.; Kirisyuk, E.M.; Belyachkov, Y.A.

1994-01-01

In the last few years a great deal of attention has been devoted to the study of the radiation conditions, which in some regions change markedly as a result of intense human activity. One reason for radioactive contamination of an area is dissemination during extraction and processing of radioactive ores or other minerals of natural radioactive elements with a high content of potassium, uranium (radium), and thorium. Estimation of the level of radioactive contamination is one of the main problems of ecological monitoring, and the quality of the measurements sometimes plays a deciding role in the fate of the object being investigated. This also pertains to, in particular, estimation of radioactive contamination of minerals employed for building homes and factories and other industrial structures. In order to draw unequivocal and well-founded conclusions from measurements of the content of natural radioactive elements in soil and rock samples, collected at the object being investigated, a great deal of attention must be devoted during the organization of the measurements to the metrological system

Chemical durability of soda-lime-aluminosilicate glass for radioactive waste vitrification

International Nuclear Information System (INIS)

Eppler, F.H.; Yim, M.S.

1998-01-01

Vitrification has been identified as one of the most viable waste treatment alternatives for nuclear waste disposal. Currently, the most popular glass compositions being selected for vitrification are the borosilicate family of glasses. Another popular type that has been around in glass industry is the soda-lime-silicate variety, which has often been characterized as the least durable and a poor candidate for radioactive waste vitrification. By replacing the boron constituent with a cheaper substitute, such as silica, the cost of vitrification processing can be reduced. At the same time, addition of network intermediates such as Al 2 O 3 to the glass composition increases the environmental durability of the glass. The objective of this study is to examine the ability of the soda-lime-aluminosilicate glass as an alternative vitrification tool for the disposal of radioactive waste and to investigate the sensitivity of product chemical durability to variations in composition

Fates of Chemical Elements in Biomass during Its Pyrolysis.

Science.gov (United States)

Liu, Wu-Jun; Li, Wen-Wei; Jiang, Hong; Yu, Han-Qing

2017-05-10

Biomass is increasingly perceived as a renewable resource rather than as an organic solid waste today, as it can be converted to various chemicals, biofuels, and solid biochar using modern processes. In the past few years, pyrolysis has attracted growing interest as a promising versatile platform to convert biomass into valuable resources. However, an efficient and selective conversion process is still difficult to be realized due to the complex nature of biomass, which usually makes the products complicated. Furthermore, various contaminants and inorganic elements (e.g., heavy metals, nitrogen, phosphorus, sulfur, and chlorine) embodied in biomass may be transferred into pyrolysis products or released into the environment, arousing environmental pollution concerns. Understanding their behaviors in biomass pyrolysis is essential to optimizing the pyrolysis process for efficient resource recovery and less environmental pollution. However, there is no comprehensive review so far about the fates of chemical elements in biomass during its pyrolysis. Here, we provide a critical review about the fates of main chemical elements (C, H, O, N, P, Cl, S, and metals) in biomass during its pyrolysis. We overview the research advances about the emission, transformation, and distribution of elements in biomass pyrolysis, discuss the present challenges for resource-oriented conversion and pollution abatement, highlight the importance and significance of understanding the fate of elements during pyrolysis, and outlook the future development directions for process control. The review provides useful information for developing sustainable biomass pyrolysis processes with an improved efficiency and selectivity as well as minimized environmental impacts, and encourages more research efforts from the scientific communities of chemistry, the environment, and energy.

Progress in the study on Pu chemical behavior under the geological environment

International Nuclear Information System (INIS)

Zhang Yingjie; Fan Xianhua

2006-01-01

The generation, characteristic, and disposal technology of the high level radioactive waste were discussed, and a progress in the study on the chemical behavior of Pu, a transuranic element possessing the long-term potential risk for the environment, under the geological repository was reviewed. Release behavior of Pu from the high level radioactive glass waste form, the basic chemical reactions of Pu possibly happening in groundwater, including solubility, complexation, redox reaction, and colloidal formation. Some proposals for the further work in China are also suggested. (authors)

Regional groundwater chemical characteristics of Aqishan pre-selected site for high level radioactive waste repository and its hydrogeological significance

International Nuclear Information System (INIS)

Guo Yonghai; Dong Jiannan; Liu Shufen; Zhou Zhichao

2014-01-01

Aqishan area located in Xinjiang Uygur Automonous Region is one of the main preselected site of disposal repository for high-level radioactive waste (HLW) in our country. Groundwater chemical feature is one of the most important consideration factors in the siting and site evaluation for high-level radioactive waste repository, From 2012 to 2013, the regional field hydrogeochemical investigation was carried out in study area and more than 30 groundwater samples were collected. According to the measurement data, the groundwater chemical features for different subareas are discussed in the paper. Furthermore, the location of discharge area of groundwater in Aqishan area was estimated according to the chemical features of different subareas. (authors)

A method for speciation of trace elements (stable and radioactive) in natural waters

International Nuclear Information System (INIS)

Salbu, B.; Bjornstad, H.E.; Pappas, A.C.

1985-01-01

Radioactive nuclides and stable trace metals entering natural aquatic systems interact with naturally occurring particles through exchange and sorption processes. The extent of which depends not only on the elements and particles in question, but also on size distribution of particles being most pronounced for colloids having large surface areas to volume ratios. The interaction of radionuclides and trace metals with colloids changes their size and charge characteristics and thereby influences their transport, mobility and bioavailability

Targets for production of high-intensity radioactive ion-beams

International Nuclear Information System (INIS)

Hagebo, E.; Hoff, P.; Steffensen, K.

1991-01-01

The recent developments of target systems for production of high intensity radioactive ion-beams at the ISOLDE mass separators is described. Methods for chemically selective production through separation of molecular ions are outlined and the effects of the addition of reactive gases has been studied. Results and further possible applications in the light element region are discussed. (author) 10 refs.; 9 figs.; 1 tab

The physical and chemical environment and radionuclide migration in a low level radioactive waste repository

International Nuclear Information System (INIS)

Torok, J.; Buckley, L.P.

1988-01-01

The expected physical and chemical environment within the low-level radioactive waste repository to be sited at Chalk River is being studied to establish the rate of radionuclide migration. Chemical conditions in the repository are being assessed for their effect on buffer performance and the degradiation of the concrete structure. Experimental programs include the effect of changes in solution chemistry on radionuclide distribution between buffer/backfill materials and the aqueous phase; the chemical stability of the buffer materials and the determination of the controlling mechanism for radionuclide transport during infiltration

Survey of chemical speciation of trace elements using synchrotron radiation

International Nuclear Information System (INIS)

Gordon, B.M.

1985-01-01

Information concerning the chemical state of trace elements in biological systems generally has not been available. Such information for toxic elements and metals in metalloproteins could prove extremely valuable in the elucidation of their metabolism and other biological processes. The shielding of core electrons by binding electrons affect the energy required for creating inner-shell holes. Furthermore, the molecular binding and the symmetry of the local environment of an atom affect the absorption spectrum in the neighborhood of the absorption edge. X-ray absorption near-edge structure (XANES) using synchrotron radiation excitation can be used to provide chemical speciation information for trace elements at concentrations as low as 10 ppM. The structure and position of the absorption curve in the region of an edge can yield vital data about the local structure and oxidation state of the trace element in question. Data are most easily interpreted by comparing the observed edge structure and position with those of model compounds of the element covering the entire range of possible oxidation states. Examples of such analyses are reviewed. 14 refs., 1 fig

General-purpose chemical analyzer for on-line analyses of radioactive solutions

International Nuclear Information System (INIS)

Spencer, W.A.; Kronberg, J.W.

1983-01-01

An automated analyzer is being developed to perform analytical measurements on radioactive solutions on-line in a hostile environment. This General Purpose Chemical Analyzer (GPCA) samples a process stream, adds reagents, measures solution absorbances or electrode potentials, and automatically calculates the results. The use of modular components, under microprocessor control, permits a single analyzer design to carry out many types of analyses. This paper discusses the more important design criteria for the GPCA, and describes the equipment being tested in a prototype unit

Major and trace elements regulation in natural granitic waters: Application to deep radioactive waste disposals

International Nuclear Information System (INIS)

Michard, G.; Negrel, G.; Toulhoat, P.; Beaucaire, C.; Ouzounian, G.

1991-01-01

In order to forecast the evolution of deep groundwaters in the environment of a radioactive waste disposal, one must be able to understand the behaviour of major and trace elements in natural systems. From granitic geothermal and groundwater systems the authors establish that major elements are controlled by mineral precipitation. Regulation levels depend both on equilibration temperature and mobile anion concentration (mainly C1). From empirical laws, the regulation levels with temperature of some trace elements (alkaline and most divalent) elements can be estimated, although a precise explanation for the regulation mechanism is not yet available. They demonstrate that some transition metals are controlled by sulphide precipitation; that uranium is controlled by uraninite solubility; that trivalent and tetravalent metals are present in association with colloidal particles. Maximum regulation levels can be estimated. Such studies can also be useful to forecast the concentration levels of many elements related to nuclear wastes, mainly fission products, uranium, thorium and by analogy artificial actinide elements, as the behaviour of corresponding natural elements can be evaluated

Removal of actinide elements from high level radioactive waste by trialkylphosphine oxide (TRPO)

International Nuclear Information System (INIS)

Song Chongli; Yang Dazhu; He Longhai; Xu Jingming; Zhu Yongjun

1992-03-01

The modified TRPO process for removing actinide elements from synthetic solution, which was taken from reprocessing of power reactor nuclear fuel, was verified by cascade experiment. Neptunium valence was adjusted in the process for improving neptunium removing efficiency. At 1 mol/L concentration of HNO 3 of feed solution and after a few stages of extraction with 30% t=TRPO kerosene, over 99.9% of Am, Pu, Np and U could be removed from HAW (high level radioactive waste) solution. The stripping of actinides loaded in TRPO are accomplished by high concentration nitric acid, oxalic acid and sodium carbonate instead of amino carboxylic complexing agents used in previous process. The actinides stripped were divided into three groups, which are Am + RE, Np + Pu, and U, and the cross contamination between them is small. Behaviours of F.P. elements are divided into three types which are not extracted, little extracted and extracted elements. The extracted elements are rare earth and Pd, Zr and Mo which are co-extracted with actinides. The separation factor between actinides and other two types of F.P.elements will increase if more scrubbing sections are added in the process. The relative concentration profile of actinide elements and Tc in various stages as well as the distribution of actinides and F.P. elements in the process stream solutions are also presented

Chemical behaviour of transuranic elements in the natural environment

International Nuclear Information System (INIS)

Kim, J.I.

1991-01-01

The chemical behaviour of transuranic elements in natural aquifer systems is governed by a variety of geochemical reactions, such as dissolution reaction (solubility), hydrolysis, complexation with inorganics or organics, redox reaction, colloid formation, geochemical interaction with surfaces of various minerals, coprecipitation, mineralisation etc. This paper reviews the present state of knowledge on some of these particular reactions. The emphasis is placed on how the individual reactions can be appraised for the long-term prediction of the geochemical behaviour of transuranic elements in the natural environment. Of the various reactions, the primary thermodynamic processes of dissolution of transuranic compounds in aquatic solution, complexation with important anions present in groundwater and colloid generation are discussed with notable examples. Various laser spectroscopy in use for the chemical speciation are mentioned briefly as for their spectroscopic capability as well as applicability. The present review discussion is primarily directed to a better understanding of the migration behaviour of transuranic elements in natural aquifer systems. (author) 100 refs

CHEMENGL/CHIMISTE, Chemical and Physical Properties of Elements

International Nuclear Information System (INIS)

Levart, Eugene

2007-01-01

Description of program or function: Data Base on basic chemical, physical, and nuclear properties of the elements in the Mendeleev Table (118 elements, 4435 nuclides comprising isotopes and isomers). Example: density electric and thermal conductivity, masses of isotopes and isomers, ionisation potential, etc. from H to Ei (Z=118). Both French and English versions are available. In addition, the French version (513 pages) contains other general information about the elements such as mineralogy, industrial applications, toxicity, historical information on discovery of the elements, etc. The latest version contains updates of atomic masses, the names of symbols of transuranium elements have been updated in accordance with the IUPAC recommendations. The values of the abundance of elements in the sun have been corrected according to Grevesse et al. The price of the different elements have been updated, some minor errors have been corrected and the presentation of the cover page has been improved. Several pages have been added to the last chapter of the French version (CHIMISTE), this chapter is not available in the English version (CHEMENGL)

Investigations concerning the source term for the emission of fission products and transuranic elements from the highly radioactive waste in the temperature region between 200 and 11000C

International Nuclear Information System (INIS)

Baumgartner, F.; Krebs, K.; Merte, B.

1984-04-01

Starting point of these investigations was the research report 290 of the former Institute for Reactor Safety, Cologne. The largely incorrect assumptions made in the chemical statement led to high radioactive doses not only for the closer, but also for the further surroundings of a reprocessing plant in case that the cooling system of the fuel element storage or the storage tank for the highly radioactive waste (HAW) should become inoperative for an extended period of time. However, as a result of this temperature region which we used in our experiments, the investigations concerning the source term of the HAW between 1100 and 1200 0 C became interesting again, because a glass melt of about 1100 0 C is used during the PAMELA-process for the vitrification of the HAW. The aqueous HAW-solution is thereby poured onto a hot glass melt. The solution thereby dries up, the HAW-salt is calcined and finally sinks into the glass melt. From today's point of view an investigation concerning the source term of the fission products and transuranic elements from the HAW at 1100 0 C therefore provides information regarding the fission product- and transuranic element volatilization within the melting furnace during the vitrification process. The results may now therefore also be considered a contribution for the layout of the off-gas purification system during the PAMELA-process

Finite element modelling of an evacuated canister for removal of molten radioactive glass

International Nuclear Information System (INIS)

Hatchell, B.K.; Deibler, J.E.; Ketner, G.L.

1994-05-01

Pacific Northwest Laboratory (PNL) has prepared a preliminary design for the West Valley Demonstration Project evacuated canister system. The function of the evacuated canister is to remove radioactive molten glass from a hot cell melter cavity during a planned melter shutdown. The proposed evacuated canister system consists of an L-shaped 4-inch 304L stainless steel (SS) schedule 40 pipe, sealed at one end with an aluminum plug and attached at the other end to a canister. While the canister is being filled, it is positioned and held above the melter at approximately 15 degree from horizontal by two turntable-mounted cranes. ANSYS finite element analyses were conducted to evaluate the heat transfer from the glass to the canister and establish a maximum canister temperature for material strength evaluation. Finite element structural analyses were conducted to identify areas that required reinforcement for high temperature use. Finite element results will be used to locate strain gauges at high stress locations during prototype testing

Recent studies of nuclear and chemical properties of elements 103, 104 and 105

International Nuclear Information System (INIS)

Hoffman, D.C.

1990-08-01

Information obtained since 1983 on the nuclear and chemical properties of element 103, the last on the actinide series, and elements 104 and 105, at the beginning of the transactinide series, is reviewed. Their chemical properties are compared with their lanthanide and lighter group 4 and 5 homologs and evidence for possible relativistic effects is discussed. The current knowledge of the nuclear properties of these elements and how these affect of the study of chemical properties is discussed. Some of the challenges involved in the study of short-lived isotopes which can only be produced an ''atom-at-a-time'' at an appropriate accelerator and the prognosis for future studies of these and still heavier elements are considered. 40 refs., 4 figs

Elemental analysis of fertilizers using X-ray fluorescence and their impact on alpha radioactivity of plants

International Nuclear Information System (INIS)

Pooja Chauhan; Chauhan, R.P.

2013-01-01

The fertilizers used for plantation contain different elements including some natural radionuclides with their daughter decay products. The radiological impact of the use of fertilizers may be due to internal irradiation of the lung by the alpha particles, short lived radon-thoron progeny and the external irradiation of the body by gamma ray emitted from the radionuclides. The aim of this study was to estimate the enhanced alpha radioactivity in different parts of plants due to fertilizers and to measure the concentration of different elements present in the fertilizers. A control study was carried out on round gourd plants using different fertilizers. Fertilizers were added to the soil just before the plantation of seeds in the pots. For the measurement of alpha track densities in different parts of plants we used α-sensitive LR-115 type II plastic track detectors. The alpha-track density (T cm -2 days -1 ) was measured in leaves of plants at different interval of time. The variation in alpha track densities was also observed in root, stem leaf and grain parts of the plants. In case of the plants grown using some phosphate fertilizers the alpha radioactivity was found to be more compared with others. A positive correlation between alpha track densities and mass exhalation rates of radon from different fertilizers has been observed. The concentration of major elements (Al, Si, P, S, Cl, K) along with other elements present in fertilizer samples was measured by X-ray fluorescence analysis. (author)

Natural radioactivity in industry, medicine, dentistry, hobbies, and camping

International Nuclear Information System (INIS)

Robertson, M.

1996-01-01

A recent enquiry asked about the potential hazards of radioactivity in gas lamp mantles. This has prompted a quick review of uses, for other reasons, of materials which are incidentally radioactive. Thorium and uranium are the two highest atomic number elements which occur naturally in commercial quantities. They are both naturally radioactive. Both have been used for a variety of purposes utilising their chemical and physical, rather than radioactive properties. They have been incorporated in specialised industrial items and in some materials encountered in everyday life. While the properties of uranium and thorium make these materials useful for a variety of purposes, the fact that they are also incidentally radioactive materials means that any potential radiological hazards should also be taken into accoutnt. The use of these materials for medical and dental purposes has been discontiunued for these reasons. The only readily availabe consumer product which uses these materials on any scale is the thoriated gas lamp mantle. The radiological consequences of this use are small. (author). 2 refs

Transport of radioactive substances

International Nuclear Information System (INIS)

2014-12-01

The report on the transport of radioactive substances covers the following topics: facts on radioactive materials transport, safety of the transport of radioactive substances, legal regulations and guidelines: a multiform but consistent system, transport of nuclear fuels, safety during the transport of nuclear fuel, future transport of spent fuel elements and high-level radioactive wastes in Germany.

Radioactivity in the environment; a case study of the Puerco and Little Colorado River basins, Arizona and New Mexico

Science.gov (United States)

Wirt, Laurie

1994-01-01

This report, written for the nontechnical reader, summarizes the results of a study from 1988-91 of the occurrence and transport of selected radionuclides and other chemical constituents in the Puerco and Little Colorado River basins, Arizona and New Mexico. More than two decades of uranium mining and the 1979 failure of an earthen dam containing mine tailings released high levels of radionuclides and other chemical constituents to the Puerco River, a tributary of the Little Colorado River. Releases caused public concern that ground water and streamflow downstream from mining were contaminated. Study findings show which radioactive elements are present, how these elements are distributed between water and sediment in the environment, how concentrations of radioactive elements vary naturally within basins, and how levels of radioactivity have changed since the end of mining. Although levels of radioactive elements and other trace elements measured in streamflow commonly exceed drinking-water standards, no evidence was found to indicate that the high concentrations were still related to uraniurn mining. Sediment radioactivity was higher at sample sites on streams that drain the eastern part of the Little Colorado River basin than that of samples from the western part. Radioactivity of suspended sediment measured in this study, therefore, represents natural conditions for the streams sampled rather than an effect of mining. Because ground water beneath the Puerco River channel is shallow, the aquifer is vulnerable to contamination. A narrow zone of ground water beneath the Puerco River containing elevated uranium concentrations was identified during the study. The highest concentrations were nearest the mines and in samples collected in the first few feet beneath the streambed. Natuxal radiation levels in a few areas of the underlying sedimentary aquifer not connected to the Puerco River also exceeded water quality standards. Water testing would enable those residents

Radioactivity in the environment: a case study of the Puerco and Little Colorado River Basins, Arizona and New Mexico

International Nuclear Information System (INIS)

Wirt, L.

1994-01-01

This report, written for the nontechnical reader, summarizes the results of a study from 1988-91 of the occurrence and transport of selected radionuclides and other chemical constituents in the Puerco and Little Colorado River basins, Arizona and New Mexico. More than two decades of uranium mining and the 1979 failure of an earthen dam containing mine tailings released high levels of radionuclides and other chemical constituents to the Puerco River, a tributary of the Little Colorado River. Releases caused public concern that ground water and streamflow downstream from mining were contaminated. Study findings show which radioactive elements are present, how these elements are distributed between water and sediment in the environment, how concentrations of radioactive elements vary naturally within basins, and how levels of radioactivity have changed since the end of mining. Although levels of radioactive elements and other trace elements measured in streamflow commonly exceed drinking-water standards, no evidence was found to indicate that the high concentrations were still related to uraniurn mining. Sediment radioactivity was higher at sample sites on streams that drain the eastern part of the Little Colorado River basin than that of samples from the western part. Radioactivity of suspended sediment measured in this study, therefore, represents natural conditions for the streams sampled rather than an effect of mining. Because ground water beneath the Puerco River channel is shallow, the aquifer is vulnerable to contamination. A narrow zone of ground water beneath the Puerco River containing elevated uranium concentrations was identified during the study. The highest concentrations were nearest the mines and in samples collected in the first few feet beneath the streambed. Natuxal radiation levels in a few areas of the underlying sedimentary aquifer not connected to the Puerco River also exceeded water quality standards. Water testing would enable those residents

On the occurrence of metallic character in the periodic table of the chemical elements.

Science.gov (United States)

Hensel, Friedrich; Slocombe, Daniel R; Edwards, Peter P

2015-03-13

The classification of a chemical element as either 'metal' or 'non-metal' continues to form the basis of an instantly recognizable, universal representation of the periodic table (Mendeleeff D. 1905 The principles of chemistry, vol. II, p. 23; Poliakoff M. & Tang S. 2015 Phil. Trans. R. Soc. A 373: , 20140211). Here, we review major, pre-quantum-mechanical innovations (Goldhammer DA. 1913 Dispersion und Absorption des Lichtes; Herzfeld KF. 1927 Phys. Rev. 29: , 701-705) that allow an understanding of the metallic or non-metallic status of the chemical elements under both ambient and extreme conditions. A special emphasis will be placed on recent experimental advances that investigate how the electronic properties of chemical elements vary with temperature and density, and how this invariably relates to a changing status of the chemical elements. Thus, the prototypical non-metals, hydrogen and helium, becomes metallic at high densities; and the acknowledged metals, mercury, rubidium and caesium, transform into their non-metallic forms at low elemental densities. This reflects the fundamental fact that, at temperatures above the absolute zero of temperature, there is therefore no clear dividing line between metals and non-metals. Our conventional demarcation of chemical elements as metals or non-metals within the periodic table is of course governed by our experience of the nature of the elements under ambient conditions. Examination of these other situations helps us to examine the exact divisions of the chemical elements into metals and non-metals (Mendeleeff D. 1905 The principles of chemistry, vol. II, p. 23). © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Use of chemical elements of 1A family by tropical tree species

International Nuclear Information System (INIS)

Carmo, Andrius M.J.; Paiva, Jose Daniel S. de; Magalhaes, Marcelo R.L. de; Franca, Elvis J. de; Hazin, Clovis A.; Bacchi, Marcio A.; Fernandes, Elisabete A.N.

2013-01-01

This study aims to evaluate the distribution of K, Rb and Cs in leaves of trees of the Atlantic Forest through studies of correlation between the chemical elements. For this, we used the Instrumental Neutron Activation Analysis for the quantification of the chemical elements. The concentration ranges found were 6700-24000 mg / kg for K, 16 to 72mg / kg for Rb and 0.08 to 0,92mg / kg for Cs. As Rb has chemical similarity to K, is easily absorbed by plants, leading to a high value (0.9) of the Pearson correlation. For the correlation between K and Cs, no significant values were detected except for some species of the Myrtaceae family. However, average correlations (0.6 < r <0.8) between Rb-Cs were obtained for seven plant species of different families. The absence of a specific pattern using of K, Rb and Cs by plants showed great complexity in the distribution of chemical elements in the ecosystem

Forest decline, natural and technically generated radioactivity

International Nuclear Information System (INIS)

Teufel, D.

1983-06-01

The question investigated is whether the radioactive rare gases emanating from nuclear plants are causative or participate in the triggering of forest disease. For one thing, a chemical reaction could be responsible for such an effect exerted by these artificial radioactive effluents. However, a calculation shows the concentration of radionuclides, respectively, in this case, their decomposition products, to be by many orders of magnitude smaller than other constituents in air; so a chemical reaction of this kind may be excluded. For the other part, rare gases might contribute to forest damage by their radioactive decomposition and late physical, chemical, and biological effects. In this connection, a detailed analysis is made of the comparability of natural radioactivity with radioactivity generated by nuclear plants. A possible contribution towards the total stress situation of forests (chemical air pollution, natural radioactivity, artificially produced radioactive rare gases, weather conditions and conditions arising from forest management and the like) would amount to a proportion smaller than 1/1000 considering natural radioactivity as a possible stress factor only. (orig.) [de

Consideration on thermodynamic data for predicting solubility and chemical species of elements in groundwater. Part 1: Tc, U, Am

Energy Technology Data Exchange (ETDEWEB)

Yamaguchi, Tetsuji; Takeda, Seiji [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1999-01-01

The solubility determines the release of radionuclides from waste form and is used as a source term in radionuclide migration analysis in performance assessment of radioactive waste repository. Complexations of radionuclides by ligands in groundwater affect the interaction between radionuclides and geologic media, thus affect their migration behavior. Thermodynamic data for Tc, Am and U were reviewed and compiled to be used for predicting the solubility and chemical species in groundwater. Thermodynamic data were reviewed with emphasis on the hydrolysis and carbonate complexation that can dominate the speciation in typical groundwater. Thermodynamic data for other species were selected based on existing database. Thermodynamic data for other important elements are under investigation, thus shown in an appendix for temporary use. (author)

Drop Test Using Finite Element Method for Transport Package of Radioactive Material

International Nuclear Information System (INIS)

Xu Xiaoxiao; Zhao Bing; Zhang Jiangang; Li Gouqiang; Wang Xuexin; Tang Rongyao

2010-01-01

Mechanical test for transport package of radioactive material is one of the important tests for demonstrating package structure design. Drop test of package is a kind of destructive test. It is a common method of adopting the pre-analysis to determine drop orientation.Mechanical test of a sealed source package was calculated with finite element method (FEM) software. Based on the analysis of the calculation results, some values were obtained such as the stress, strain, acceleration and the drop orientation which causes the most severe damage, and the calculation results were compared with the results of test. (authors)

Chemistry of the heaviest elements--one atom at a time

International Nuclear Information System (INIS)

Hoffman, Darleane C.; Lee, Diana M.

2000-01-01

In keeping with the goal of the Viewpoint series of the Journal of Chemical Education, this article gives a 75-year perspective of the chemistry of the heaviest elements, including a 50-year retrospective view of past developments, a summary of current research achievements and applications, and some predictions about exciting, new developments that might be envisioned within the next 25 years. A historical perspective of the importance of chemical separations in the discoveries of the transuranium elements from neptunium (Z=93) through mendelevium (Z=101) is given. The development of techniques for studying the chemical properties of mendelevium and still heavier elements on the basis of measuring the radioactive decay of a single atom (''atom-at-a-time'' chemistry) and combining the results of many separate experiments is reviewed. The influence of relativistic effects (expected to increase as Z 2 ) on chemical properties is discussed. The results from recent atom-at-a-time studies of the chemistry of the heaviest elements through seaborgium (Z=106) are summarized and show that their properties cannot be readily predicted based on simple extrapolation from the properties of their lighter homologues in the periodic table. The prospects for extending chemical studies to still heavier elements than seaborgium are considered and appear promising

Consideration on thermodynamic data for predicting solubility and chemical species of elements in groundwater. Part 2: Np, Pu

International Nuclear Information System (INIS)

Yamaguchi, Tetsuji

2000-11-01

The solubility determines the release of a radionuclide from waste form and is used as a source term in radionuclide migration analysis in performance assessment of radioactive waste repository. Complexations of the radionuclide by ligands in groundwater affect the interaction between radionuclides and geologic media, thus affect their migration behavior. It is essential to estimate the solubility and to predict the chemical species for the radionuclide based on thermodynamic data. The thermodynamic data of aqueous species and compounds were reviewed and compiled for Np and Pu. Thermodynamic data were reviewed with emphasis on the hydrolysis and carbonate complexation that can dominate the speciation in groundwater. Thermodynamic data for other species were selected based on existing databases. Thermodynamic data for other important elements are under investigation, thus shown in an appendix for temporary use. (author)

Multielement analysis of reagents used in chemical identification of transuranic elements

International Nuclear Information System (INIS)

Montalvan Estrada, A.; Brigido Flores, O.; Maslov, O.D.; Dmitriev, S.N.

2006-01-01

For more than 40 years, chemical identification of transuranic elements has been used at the Laboratory of Nuclear Reactions of the Join Institute for Nuclear Research, Dubna, Russia, as a secondary method of identification. Chlorination of transuranic elements obtained by nuclear reactions is an important step of the procedure in order to obtain volatile compounds able to pass through a thermo chromatographic process. To access the quality of the reagents TiCl 4 and SOCl 2 multielement analysis was carried out using both X-rays fluorescence and gamma activation. It was followed the simplest procedure for reagents samples pretreatment, so further interferences from other chemical products were avoided. X-rays fluorescence analysis was performed in a spectrometer with Si(Li) detector with a resolution for Fe (K?) of 190 eV. Both Cd-109 and Am-241 were used as isotopic sources of excitation. Gamma activation analysis was carried out using the compact electron accelerator MT-25, where gamma rays are produced in a stopping target. Among the parameters of the MT-25 are the following: energy range-10-25 MeV, gamma-ray flux-10 14 photon/s, power consumption-20 kw. Measurements of the induced activity were performed with the help of a HPGe detector, thin and coaxial Ge(Li) detectors. There were identified two elements in SOCl 2 -Nickel (3*10 -6 g/g) and Antimony (2*10 -7 g/g), while there were identified three elements in TiCl 4 - Zirconium (8*10 -7 g/g), Arsenic (9*10 -7 g/g) and Antimony (5*10 -7 g/g). Only five elements were detected in trace concentrations in the two analyzed reagents, that is for more than 57 elements capable of being detected using gamma activation analysis with the MT-25 only 5 had concentrations above the detection limits of the method. Not being chemical analogs of the synthesized transuranic elements (Z-104 and 106) and not being able to alpha or fission disintegrations there is not expected any interference from them in the chemical

The interaction between bitumen matrix and chemical components of radioactive wastes of WWER type

International Nuclear Information System (INIS)

Selucky, P.; Sazavsky, P.; Peka, V.; Krupka, M.

2000-01-01

The interaction between bitumen matrix and chemical components of WWER type radioactive wastes was studied. So called ''cold'' model bitumen products were prepared and compared with real products using macroDTA method. On the basis of obtained curves, the evaluation of bitumen product fire risks was performed with the aim to minimize risks of bituminization process. (authors)

PRINCIPLE ROCK TYPES FOR RADIOACTIVE WASTE REPOSITORIES

Directory of Open Access Journals (Sweden)

Sibila Borojević Šostarić

2012-07-01

Full Text Available Underground geological storage of high- and intermediate/low radioactive waste is aimed to represent a barrier between the surface environment and potentially hazardous radioactive elements. Permeability, behavior against external stresses, chemical reacatibility and absorption are the key geological parameters for the geological storage of radioactive waste. Three principal rock types were discussed and applied to the Dinarides: (1 evaporites in general, (2 shale, and (3 crystalline basement rocks. (1 Within the Dinarides, evaporite formations are located within the central part of a Carbonate platform and are inappropriate for storage. Offshore evaporites are located within diapiric structures of the central and southern part of the Adriatic Sea and are covered by thick Mesozoic to Cenozoic clastic sediment. Under very specific circumstances they can be considered as potential site locations for further investigation for the storage of low/intermediate level radioactive wast e. (2 Thick flysch type formation of shale to phyllite rocks are exposed at the basement units of the Petrova and Trgovska gora regions whereas (3 crystalline magmatic to metamorphic basement is exposed at the Moslavačka Gora and Slavonian Mts. regions. For high-level radioactive waste, basement phyllites and granites may represent the only realistic potential option in the NW Dinarides.

Airborne chemical elements in Spanish moss

Energy Technology Data Exchange (ETDEWEB)

Shacklette, H.T.; Connor, J.J.

1973-01-01

Spanish moss (Tillandsia usneoides L.), collected from its geographic range in Southern United States, was analyzed for 38 chemical elements in 123 samples. Analyses of Spanish moss samples collected at rural, residential, highway, and industrial locations reflected significant differences in concentrations of metals. Samples from industrial and highway locations are characterized as containing greater-than-average amounts of arsenic, cadmium, chromium, cobalt, copper, lead, nickel, and vanadium. The high levels of lead found in some samples from highway locations are especially noteworthy. Many samples from sites near the seashore contained greater-than-average amounts of sodium that is thought to have been derived from ocean spray. Samples from rural locations commonly contain low concentrations of the metal usually associated with industrial or urban activity but may contain large amounts of the elements that are ordinary constituents of soil dust. Four of six samples containing detectable amounts of tin were collected within 50 miles of the only tin smelter in the United States; this result suggests that elemental analyses of Spanish moss samples can provide an economical and rapid method of estimating the kind and relative degree of local atmospheric metal pollution.

Curie's hypotheses concerning radioactivity and the origin of the elements

Energy Technology Data Exchange (ETDEWEB)

Kuroda, P.K.

1999-09-01

Pierre Curie gave two hypotheses at first; (1) It can be supposed that the radioactive substances borrow the energy, which they release, from an external radiation, and their radiation would then be a secondary radiation, (2) It can be supposed that the radioactive substances draw from themselves the energy which they release. The second hypothesis has shown the more fertile in explaining the properties of the radioactive substances. Consequently, the first hypothesis became more or less forgotten. It appears, however, the first hypothesis should play an important role in explaining the phenomena concerning the origin of the elements. The Oklo Phenomenon has demonstrated that a nuclear fire had once existed on our planet earth and formation of heavy elements was occurring in nature. The author pointed out that the difference in the isotopic compositions of xenon found in meteorites, lunar samples and in the earth's atmosphere can only be explained as due to the alterations of the isotropic compositions of xenon by combined effect of (a) mass-fractionation, (b) spallation, and (c) stellar temperature neutron-capture reactions. The strange xenon components are not isotopically pure substance. Instead, xenon-HL is a mixture of the {sup 244}Pu fission xenon and the xenon whose isotopic compositions is severely altered by a combined effect of the processes (a), (b) and (c) mentioned above. These results also indicate that C1 carbonaceous chondrites, which is generally as the most primitive sample of the solar system material, began to retain its xenon 5.1 billion years ago, when the plutonium to uranium ratio in the solar system was as high as almost 0.6 (atom/atom), while the C2 carbonaceous chondrite began to retain their xenon about 150 million years later and the ordinary chondrites and achondrite about 500 to 600 million years later. This means that the birth of the solar system began soon after the last supernova exploded about 5.1 billion years ago, and the

Radioactive elements on Mercury's surface from MESSENGER: implications for the planet's formation and evolution.

Science.gov (United States)

Peplowski, Patrick N; Evans, Larry G; Hauck, Steven A; McCoy, Timothy J; Boynton, William V; Gillis-Davis, Jeffery J; Ebel, Denton S; Goldsten, John O; Hamara, David K; Lawrence, David J; McNutt, Ralph L; Nittler, Larry R; Solomon, Sean C; Rhodes, Edgar A; Sprague, Ann L; Starr, Richard D; Stockstill-Cahill, Karen R

2011-09-30

The MESSENGER Gamma-Ray Spectrometer measured the average surface abundances of the radioactive elements potassium (K, 1150 ± 220 parts per million), thorium (Th, 220 ± 60 parts per billion), and uranium (U, 90 ± 20 parts per billion) in Mercury's northern hemisphere. The abundance of the moderately volatile element K, relative to Th and U, is inconsistent with physical models for the formation of Mercury requiring extreme heating of the planet or its precursor materials, and supports formation from volatile-containing material comparable to chondritic meteorites. Abundances of K, Th, and U indicate that internal heat production has declined substantially since Mercury's formation, consistent with widespread volcanism shortly after the end of late heavy bombardment 3.8 billion years ago and limited, isolated volcanic activity since.

Design of chemical treatment unit for radioactive liquid wastes in Serpong nuclear facilities

International Nuclear Information System (INIS)

Salimin, Z.; Walman, E.; Santoso, P.; Purnomo, S.; Sugito; Suwardiyono; Wintono

1996-01-01

The chemical treatment unit for radioactive liquid wastes arising from nuclear fuel fabrication, radioisotopes production and radiometallurgy facility has been designed. The design of chemical processing unit is based on the characteristics of liquid wastes containing fluors from uranium fluoride conversion process to ammonium uranyl carbonate on the fuel fabrication. The chemical treatment has the following process steps: coagulation-precipitation of fluoride ion by calcium hydroxide coagulant, separation of supernatant solution from sludge, coagulation of remaining fluoride on the supernatant solution by alum, separation of supernatant from sludge, and than precipitation of fluors on the supernatant by polymer resin WWS 116. The processing unit is composed of 3 storage tanks for raw liquid wastes (capacity 1 m 3 per tank), 5 storage tanks for chemicals (capacity 0.5 m 3 per tank), 2 mixing reactors (capacity 0.5 m 3 per reactor), 1 storage tank for supernatant solution (capacity 1 m 3 ), and 1 storage tank for sludge (capacity 1 m 3 )

Model Experiments on Chemical Properties of Superheavy Elements in Aqueous Solutions

CERN Document Server

Szeglowski, Z

2003-01-01

This paper presents a brief review of model experiments on investigation of chemical properties of transactinide elements, ranging from 104 to 116. The possibilities of isolation of the nuclei of these elements from nuclear reaction products, using the ion-exchange method, are also considered.

Preliminary study of radioactive limonite localities in Colorado, Utah, and Wyoming

Science.gov (United States)

Lovering, T.G.; Beroni, E.P.

1956-01-01

Nine radioactive limonite localities of different types were sampled during the spring and fall of 1953 in an effort to establish criteria for differentiating limonite outcrops associated with uranium or thorium deposits from limonite outcrops not associated with such deposits. The samples were analyzed for uranium and thorium by standard chemical methods, for equivalent uranium by the radiometric method, and for a number of common metals by semiquantitative geochemical methods. Correlation coefficients were then calculated for each of the metals with respect to equivalent uranium, and to uranium where present, for all of the samples from each locality. The correlation coefficients may indicate a significant association between uranium or thorium and certain metals. Occurrences of specific that are interpreted as significant very considerably for different uranium localities but are more consistent for the thorium localities. Samples taken from radioactive outcrops in the vicinity of uranium or thorium deposits can be quickly analyzed by geochemical methods for various elements. Correlation coefficients can then be determined for the various elements with respect to uranium or thorium; if any significant correlations are obtained, the elements showing such correlation may be indicators of uranium or thorium. Soil samples of covered areas in the vicinity of the radioactive outcrop may then be analyzed for the indicator elements and any resulting anomalies used as a guide for prospecting where the depth of overburden is too great to allow the use of radiation-detecting instruments. Correlation coefficients of the associated indicator elements, used in conjunction with petrographic evidence, may also be useful in interpreting the origin and paragenesis of radioactive deposits. Changes in color of limonite stains on the outcrop may also be a useful guide to ore in some areas.

Chemical treatment of radioactive liquid wastes from medical applications

International Nuclear Information System (INIS)

Castillo A, J.

1995-01-01

This work is a study about the treatment of the most important radioactive liquid wastes from medical usages, generated in medical institutions with nuclear medicine services. The radionuclides take in account are 32 P, 35 S, 125 I. The treatments developed and improved were specific chemical precipitations for each one of the radionuclides. This work involve to precipitate the radionuclide from the liquid waste, making a chemical compound insoluble in the aqueous phase, for this process the radionuclide stay in the precipitate, lifting the aqueous phase with a very low activity than the begin. The 32 P precipitated in form of Ca 3 32 P O 4 and Ca 2 H 32 P O 4 with a value for Decontamination Factor (DF) at the end of the treatment of 32. The 35 S was precipitated in form of Ba 35 SO 4 with a DF of 26. The 125 I was precipitated in Cu 125 I to obtain a DF of 24. The results of the treatments are between the limits given for the International Atomic Energy Agency and the 10 Code of Federal Regulation 20, for the safety release at the environment. (Author)

Mapping of transuranic elements in soil by nuclear track methodology

International Nuclear Information System (INIS)

Espinosa, G.

2001-01-01

An alternative method is presented to map the distribution of transuranic elements, which is characterized by its simplicity in both implementation and instrumentation. The method is based on the interaction of alpha particles in polymeric materials and the formation of tracks, which become visible after chemical etching. Nuclear track detectors are placed on the soil in order to evaluate the distribution of the radioactive material and its relative intensity for transuranic contaminants. CR-39 polycarbonate was used as a nuclear track detector in this study. Chemical etching was done with a 6.25M KOH solution in a closed system for 16 hours. The readings were performed in an automatic system using digital image analysis. The results show the distribution of the contaminants and their location, identifying the zones with large intensities. This method is attractive for use in areas contaminated with alpha particles, and specially transuranic elements, because it involves in situ measurements, generates very low amounts of radioactive waste, and the detectors are easily handled. (author)

Some peculiarities of radioactive elements metabolism in body according to the indices of activity of blood and urine in malignant neoplasms of different localization

International Nuclear Information System (INIS)

Gelashvili, K.D.

1988-01-01

Background beta-radioactivity of blood and day urine in 115 patients (36 healthy ones and 79 suffering from malignant tumor of different localization) taking into account age was determined. It is shown that changes in background radioactivity of blood and urine both in healthy and oncologic patients are mostly presented in old age. Increase of background radioactivity of blood and urine takes place mainly not due to 40 K, but other beta-active elements - in healthy persons. Activity of blood and day urine in patients with malignant tumors decreases due to other beta-emittor, but not 40 K. Some changes in metabolic processes of beta-active elements of an organism both with the growth increase and when developing malignant tumors are established. 1 tab

Matching Element Symbols with State Abbreviations: A Fun Activity for Browsing the Periodic Table of Chemical Elements

Science.gov (United States)

Woelk, Klaus

2009-01-01

A classroom activity is presented in which students are challenged to find matches between the United States two-letter postal abbreviations for states and chemical element symbols. The activity aims to lessen negative apprehensions students might have when the periodic table of the elements with its more than 100 combinations of letters is first…

EDXRF applied to the chemical element determination of small invertebrate samples

International Nuclear Information System (INIS)

Magalhaes, Marcelo L.R.; Santos, Mariana L.O.; Cantinha, Rebeca S.; Souza, Thomas Marques de; Franca, Elvis J. de

2015-01-01

Energy Dispersion X-Ray Fluorescence - EDXRF is a fast analytical technique of easy operation, however demanding reliable analytical curves due to the intrinsic matrix dependence and interference during the analysis. By using biological materials of diverse matrices, multielemental analytical protocols can be implemented and a group of chemical elements could be determined in diverse biological matrices depending on the chemical element concentration. Particularly for invertebrates, EDXRF presents some advantages associated to the possibility of the analysis of small size samples, in which a collimator can be used that directing the incidence of X-rays to a small surface of the analyzed samples. In this work, EDXRF was applied to determine Cl, Fe, P, S and Zn in invertebrate samples using the collimator of 3 mm and 10 mm. For the assessment of the analytical protocol, the SRM 2976 Trace Elements in Mollusk produced and SRM 8415 Whole Egg Powder by the National Institute of Standards and Technology - NIST were also analyzed. After sampling by using pitfall traps, invertebrate were lyophilized, milled and transferred to polyethylene vials covered by XRF polyethylene. Analyses were performed at atmosphere lower than 30 Pa, varying voltage and electric current according to the chemical element to be analyzed. For comparison, Zn in the invertebrate material was also quantified by graphite furnace atomic absorption spectrometry after acid treatment (mixture of nitric acid and hydrogen peroxide) of samples have. Compared to the collimator of 10 mm, the SRM 2976 and SRM 8415 results obtained by the 3 mm collimator agreed well at the 95% confidence level since the E n Number were in the range of -1 and 1. Results from GFAAS were in accordance to the EDXRF values for composite samples. Therefore, determination of some chemical elements by EDXRF can be recommended for very small invertebrate samples (lower than 100 mg) with advantage of preserving the samples. (author)

The structures and stability of media intended for the immobilization of high level radioactive waste

International Nuclear Information System (INIS)

Tempest, P.A.

1979-05-01

High level radioactive waste contains about 40 different elements and, in time, many of these elements are transformed by radioactive decay into different-sized atoms with new chemical properties. The suitability of ordered crystal structures and unordered glass structures as media for immobilising the waste elements is compared. The structural properties of a mixture of synthetic minerals (SYNROC) are described and the various minerals' ability to accommodate ions of different radii and charge assessed. Similary the unordered structure of glass is examined and the probability of the glass remaining non-crystalline during manufacture and storage taken into account. Alternative glassification technologies in the form of the French AVM continuous process and the UK HARVEST batch processes are described and compared, and their likely effect on the structural properties of the final solid glass block considered. (author)

Magnesium Potassium Phosphate Compound for Immobilization of Radioactive Waste Containing Actinide and Rare Earth Elements

Directory of Open Access Journals (Sweden)

Sergey E. Vinokurov

2018-06-01

Full Text Available The problem of effective immobilization of liquid radioactive waste (LRW is key to the successful development of nuclear energy. The possibility of using the magnesium potassium phosphate (MKP compound for LRW immobilization on the example of nitric acid solutions containing actinides and rare earth elements (REE, including high level waste (HLW surrogate solution, is considered in the research work. Under the study of phase composition and structure of the MKP compounds that is obtained by the XRD and SEM methods, it was established that the compounds are composed of crystalline phases—analogues of natural phosphate minerals (struvite, metaankoleite. The hydrolytic stability of the compounds was determined according to the semi-dynamic test GOST R 52126-2003. Low leaching rates of radionuclides from the compound are established, including a differential leaching rate of 239Pu and 241Am—3.5 × 10−7 and 5.3 × 10−7 g/(cm2∙day. As a result of the research work, it was concluded that the MKP compound is promising for LRW immobilization and can become an alternative material combining the advantages of easy implementation of the technology, like cementation and the high physical and chemical stability corresponding to a glass-like compound.

Prevention of radioactive gas seeping into buildings through constructive materials

International Nuclear Information System (INIS)

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

2004-01-01

Full text: One of possible method of realization of the terrorist acts is using gases and liquids, which easily permeate through the constructive materials of walls, floor, ceiling, roof, etc. into buildings by the capillary action of the pores. Toxic volatile organic compounds, organic and inorganic gases, radioactive elements, especially, which emits alpha particles can be used as the dangerous substances. Increased ventilation may help in removing the gases, but can actually increase the gases level by increasing the suction through the pores of concrete. If the gases and liquids are soluble in water and are easily volatilized from it, they can also get by groundwater up to underground structures and penetrate inside through opening and pores in concrete or pushed by hydrostatic pressure. The purpose of this work is creating a method to reduce concentration of toxic and radioactive gases in homes, buildings, underground buildings, tunnels, hangars, garages, bomb shelters, etc. The most effective method to prevent penetration of radionuclides into premises of buildings and underground structures through walls, roofs, floors is using special chemicals, which seal micropores inside the construction materials against gases. Worked out chemicals which consist of blend of polymeric compounds are described in the paper. Radioactive gases permeability in constructive materials after treatment by chemicals was studied. Influence of types of cement, sand and gypsum, preliminary treatment by different chemicals, different types of polymeric compounds, time between treatments, moisture of materials, time between preparation of chemicals and treatment of materials (aging of chemicals), time between treatment of concrete and testing (aging of treated concrete) were examined. Experiments have shown that our method allows reducing the coefficient of gas permeability 200 - 400 times

Utilization of chemical derivatives in activation analysis

International Nuclear Information System (INIS)

Ehmann, W.D.

1990-01-01

Derivative activation analysis (DAA) is a method to enhance the sensitivity of nuclear activation analysis for the more elusive elements. It may also allow a degree of chemical speciation for the element of interest. DAA uses a preirradiation chemical reaction on the sample to initiate the formation of, or an exchange with, a chemical complex which contains a surrogate element, M. As a result, the amount of the element or the chemical species to be determined, X, is now represented by measurement of the amount of the surrogate element, M, that is made part of, or released by the complex species. The surrogate element is selected for its superior properties for nuclear activation analysis and the absence of interference reaction in its final determination by instrumental neutron activation analysis (INAA) after some preconcentration or separation chemistry. Published DAA studies have been limited to neutron activation analysis. DAA can offer the analyst some important advantages. It can determine elements, functional groups, or chemical species which cannot be determined directly by INAA, fast neutron activation analysis (FNAA), prompt gamma neutron activation analysis (PGNAA), or charged particle activation analysis (CPAA) procedures. When compared with conventional RNAA, there are fewer precautions with respect to handling of intensely radioactive samples, since the chemistry is done before the irradiation. The preirradiation chemistry may also eliminate many interferences that might occur in INAA and, through use of an appropriate surrogate element, can place the analytical gamma-ray line in an interference-free region of the gamma-ray spectrum

Physical, chemical and radioactive characterization of co-products from titanium dioxide industry for valorization in the cement industry

International Nuclear Information System (INIS)

Gazquez, M.J.; Mantero, J.; Bolivar, J.P.; Garcia-Tenorio, R.; Vaca, F.

2011-01-01

The present study was conducted to characterize the raw materials (ilmenite and slag), waste (red gypsum) and several co-products (sulphate monohydrate and sulphate heptahydrated) form the titanium dioxide industry in relation to their elemental composition (major, minor and trace elements), granulometry, mineralogy, microscopic morphology, physical composition and radioactive content in order to apply this knowledge in the valorization of the co-products in the fields such a as construction, civil engineering, etc. In particular, the main properties of cements produced with different proportions of red gypsum were studied, and the obtained improvements, in relation to Ordinary Portland Cements (OPC) were evaluated. It was also demonstrated that the levels of pollutants and the radioactive content in the produced RG cements, remain within the regulated safety limits. (Author). 38 refs.

Chemical elements dynamic in the fermentation process of ethanol producing

International Nuclear Information System (INIS)

Nepomuceno, N.; Nadai Fernandes, E.A. de; Bacchi, M.A.

1994-01-01

This paper provides useful information about the dynamics of chemical elements analysed by instrumental neutron activation analysis (INAA) and, found in the various segments of the fermentation process of producing ethanol from sugar cane. For this, a mass balance of Ce, Co, Cs, Eu, Fe, Hf, La, Sc, Sm, and Th, terrigenous elements, as well as Br, K, Rb, and Zn, sugar cane plant elements, has been demonstrated for the fermentation vats in industrial conditions of ethanol production. (author). 10 refs, 4 figs, 1 tab

Behavior of radon, chemical compounds and stable elements in underground water

International Nuclear Information System (INIS)

Lopez R, N.; Segovia, N.; Lopez, M.B.E.; Pena, P.; Armienta, M.A.; Godinez, L.; Seidel, J.L.

2001-01-01

The radon behavior, chemical compounds, major and trace elements in water samples of four springs and three wells of urban and agricultural zones around the Jocotitlan volcano and El Oro region was determined, both of them located in the medium part of the Mexican neo-volcanic axis. The 222 Rn was measured by the liquid scintillation method, the analysis of major components was realized with conventional chemical techniques, while the trace elements were quantified using an Icp-Ms. The average values of the radon concentrations obtained during one year were constant relatively, in an interval from 0.97 to 4.99 Bq/lt indicating a fast transport from the reload area toward the sampling points. the compounds, major and trace elements showed differences which indicate distinct origins of water from the site studies. (Author)

Risk perception: expert opinion versus public understanding. [Of radioactive waste repositories

Energy Technology Data Exchange (ETDEWEB)

Brown, J

1987-02-01

A research project looking at the public's attitudes towards the siting of radioactive waste depositories is reported. The risk perception studies seek to compare expert and lay understanding of risk. Adverse public reactions to risk can only be understood if it is known how people relate to risks in their everyday or working lives. Social trends and experiences are important, for example, the adverse public opinion on the siting of nuclear waste facilities. A number of elements have been identified as common to different risk areas such as chemicals, drugs, food or radioactive waste. These are the clashing of values, polarization of beliefs or clashes of interest.

Mass spectrographic analysis of selected chemical elements by microbial leaching of zircon

International Nuclear Information System (INIS)

Becker, S.; Dietze, H.J.; Bullmann, M.; Iske, U.

1986-01-01

Spark source mass spectrometry is a useful method for chemical element analysis of geological and biological samples. This sensitive technique (detection limit down to the ppb-range) is used to analyze leaching processes by means of several microorganisms. The problem of microbial leaching of chemical resistent materials was tested under laboratory conditions with regard to possible analytical and technical applications. Leaching of metals with chemolithotrophic and heterotrophic, organic acids producing microorganisms has been investigated with zircon from the Baltic Shield containing 0.7% rare earth elements and 1.67% hafnium. When zircon is leached with strains of thiobacillus ferrooxidans about 80% of the rare earth elements, Hf, Th and U can be recovered. (orig.) [de

Development of a novel heavy element chemistry apparatus using the RIKEN gas-field recoil separator as a pre-separator

International Nuclear Information System (INIS)

Haba, H.; Morita, K.; Enomoto, S.; Morimoto, K.; Kaji, D.; Nagame, Yuichiro

2004-01-01

A new system was developed, that supplied the super-heavy element separated physically as the former steps to the chemical analysis devices such as a gas or liquid chromatographs. The gas jet transportation device was newly set up on the edge of existing accelerator research facilities in the Institute of Physical and Chemical Research linac building (GARIS). To conduct the chemical separation experiment of a super-heavy element of 112 in future a radioactive isotope of mercury of light homology elements was manufactured with a gas jet uniting type online multi-tracer manufacturing device. The adsorption chromatograph experiment to the gold was performed using this system. (H. Katsuta)

Naturally occurring radioactive elements, arsenic and other metals in drinking water from private wells; Naturligt radioaktiva aemnen, arsenik och andra metaller i dricksvatten fraan enskilda brunnar

Energy Technology Data Exchange (ETDEWEB)

Ek, Britt-Marie; Thunholm, Bo (Geological Survey of Sweden (SGU), Uppsala (SE)); Oestergren, Inger; Falk, Rolf; Mjoenes, Lars (Swedish Radiation Protection Authority, Stockholm (Sweden))

2008-04-15

Approximately 50% of all drinking water is extracted from groundwater. For private supply of drinking water almost 100% emanates from groundwater. For approximately 1.2 of the 9 million Swedish citizens, private wells are the primary water source where 700 000 get their water from wells drilled in the bedrock. Radioactive elements and metals that occur naturally in the bedrock can be found in the well water. The radioactive elements include radon-222 (222Rn), uranium (U), radium-226 (226Ra) as well as polonium-210 (210Po) and lead-210 (210Pb), which are long-lived progeny of radon. In 2001 SGU and SSI initiated a collaboration to investigate the occurrence of radioactive elements and metals in water from private wells. Data sampling and analysis was completed in 2006. The aim of the project was to map the occurrence of radioactive elements in drinking water from private wells and to estimate their respective dose contribution. Another aim was to map metals and other elements in the water, to study temporal variations and possible co-variations between analysed elements. Sampling was conducted in a random fashion throughout the country. However, in regions where bedrock and soils are known to show enhanced concentrations of radioactive elements and arsenic the sampling density was increased. The analyses comprises: total beta activity, total alpha activity, radium-226, radon-222, uranium, aluminium, chloride, calcium, vanadium, chromium, iron, manganese, cobalt, nickel, copper, zink, arsenic, strontium, molybdenum, cadmium, barium, lead, thorium, boron, sodium, manganese, potassium, silica, alkalinity, sulfate, fluoride, phosphate, nitrate, pH and electric conductivity. In a few cases chemistry analyses of polonium-210 and lead-210 have been done. It was observed that the south-western part of Sweden, with exception for granite areas in the county of Bohuslaen, has relatively low concentrations of natural radioactive elements in the drinking water. The occurrence of

Environmental radioactivity in Slovakia/Czechoslovakia in 1961 to 1975

International Nuclear Information System (INIS)

Csupka, S.; Carach, J.; Petrasova, M.

1978-01-01

The results are given of environmental monitoring of 90 Sr and 137 Cs in Slovakia between 1961 to 1975. Samples of radioactive fallout, milk and water were taken monthly, samples of forage, cereals and vegetables were taken in the ripening stage, and samples of foodstuffs were taken in shops. The following amounts of samples were used for the analyses: 100 g of soil, 100 g of dry forage, 100 g of dry cereals, 3 kg of fresh fruit and vegetables, 2 l of water, 1 l of milk, 2 kg of fresh meat, and flour and flour products amounting to 2 kg. The samples were dried, burned and mineralized for 24 hours with HCl. After removal of interfering elements, ie., Fe, 140 Ba, 140 La, rare earths, phosphates and 90 Y, the 90 Sr activity was determined by the yttrium method. The yttrium chemical yield was 90%. 137 Cs beta activity was determined after precipitation from a solution in the form of cesium nickel ferrocyanide and after removal of oxalates, alkali elements and rare earth elements. Chemical yield was 60 to 70%. An anticoincidence low-level beta counter by Philips was used in activity measurement. The detection efficiency was 22% for 90 Sr- 90 Y and 17% for 137 Cs. The relative mean square error of the measurement was lower than 15% for 90 Y and 10% for 137 Cs. The measurement results are classified in five parts, viz., radioactivity in fallout, in soils, in water, in plants, and in food. (J.P.)

Upper parameters of toxicity (LDsub(50/30)) of some radioactive and chemical substances

International Nuclear Information System (INIS)

Rodionova, L.F.; Kupriyanova, V.M.; Zasedatelev, A.A.

1978-01-01

The toxicities of radioactive ( 90 Sr, 210 Po) and chemical (lead nitrate, mercuric chloride) substances were compared using equivalent procedures. Ninety six doses of toxic substances in various concentrations were tested on mice to which these substances were administered by intragastric intubation. The material was processed and analyzed by conventional methods used in toxicology. The upper limits of toxicity for the tested substances were determined from their LDsub(50/30) values by various methods of calculation

Allium-test as a tool for toxicity testing of environmental radioactive-chemical mixtures

Science.gov (United States)

Oudalova, A. A.; Geras'kin, S. A.; Dikareva, N. S.; Pyatkova, S. V.

2017-01-01

Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium-test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium-test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds.

Trace elements and naturally occurring radioactive materials in 'Non-traditional fertilizers' used in Ghana

International Nuclear Information System (INIS)

Assibey, E. O.

2013-07-01

Fertilizers have been implicated for being contaminated with toxic trace elements and naturally occurring radioactive materials (NORMs) even though they are an indispensable component of our agriculture. This phenomenon of contamination has been investigated and established world-wide in various forms of fertilizers (i.e., granular or 'traditional' type and liquid/powder or 'non-traditional type'). In Ghana, the crop sub-sector has seen a gradual rise in the importation and use of 'non-traditional fertilizers' which are applied to both the foliar parts and roots of plants. This notwithstanding, research on fertilizers has been largely skewed towards the 'traditional' types, focusing principally on the subjects of yield, effects of application and their quality. This study was, therefore, undertaken to bridge the knowledge gap by investigating the levels of trace elements and NORMs found in the 'non-traditional' fertilizers used in Ghana. The principal objective of the study was to investigate the suitability of the 'non-traditional fertilizers' for agricultural purposes with respect to trace elements and NORMs contamination. Atomic Absorption Spectrometry and instrumental Neutron Activation Analysis were employed to determine the trace elements (Cu, Zn, Fe, Na, Al, Br, Ni, Cd, As, Hg, Co, Pb, La, Mn, Si, Ca, Cl, S, K, Ba and V) and NORMs ( 238 U, 232 Th and 40 K) concentrations in thirty-nine (39) fertilizer samples taken from two major agro-input hubs in the country (Kumasi-Kejetia and Accra). Multivariate statistical analyses (cluster analysis, principal component analysis and pearson's correlation) were applied to the data obtained in order to identify possible sources of contamination, investigate sample/ parameter affinities and groupings and for fingerprinting. The toxic trace element concentrations determined in all samples were found to be in the order Fe>Cu>Co>Cd>Cr >Ni>Pb>As>Hg. The study found most of the trace elements determined to be within limits set

Direct conversion of radioactive and chemical waste containing metals, ceramics, amorphous solids, and organics to glass

International Nuclear Information System (INIS)

Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

1994-01-01

The Glass Material Oxidation and Dissolution System (CMODS) is a new process for direct conversion of radioactive, mixed, and chemical wastes to glass. The wastes can be in the chemical forms of metals, ceramics, amorphous solids, and organics. GMODS destroys organics and it incorporates heavy metals and radionuclides into a glass. Processable wastes may include miscellaneous spent fuels (SF), SF hulls and hardware, plutonium wastes in different forms, high-efficiency particulate air (HEPA) filters, ion-exchange resins, failed equipment, and laboratory wastes. Thermodynamic calculations indicate theoretical feasibility. Small-scale laboratory experiments (< 100 g per test) have demonstrated chemical laboratory feasibility for several metals. Additional work is needed to demonstrate engineering feasibility

Chemical Technology Division progress report, April 1, 1983-March 31, 1985

International Nuclear Information System (INIS)

1985-10-01

The status of the following programs is reported: fission energy; nuclear and chemical waste management; environmental control technology; basic science and technology; biotechnology programs; transuranium-element processing; Nuclear Regulatory Commission programs; Consolidated Edison Uranium Solidification Project; radioactive materials production; computer 1 engineering applications; and miscellanous programs

Chemical Technology Division progress report, April 1, 1983-March 31, 1985

Energy Technology Data Exchange (ETDEWEB)

1985-10-01

The status of the following programs is reported: fission energy; nuclear and chemical waste management; environmental control technology; basic science and technology; biotechnology programs; transuranium-element processing; Nuclear Regulatory Commission programs; Consolidated Edison Uranium Solidification Project; radioactive materials production; computer 1 engineering applications; and miscellanous programs.

X rays and radioactivity: a complete surprise

International Nuclear Information System (INIS)

Radvanyi, P.; Bordry, M.

1995-01-01

The discoveries of X rays and of radioactivity came as complete experimental surprises; the physicists, at that time, had no previous hint of a possible structure of atoms. It is difficult now, knowing what we know, to replace ourselves in the spirit, astonishment and questioning of these years, between 1895 and 1903. The nature of X rays was soon hypothesized, but the nature of the rays emitted by uranium, polonium and radium was much more difficult to disentangle, as they were a mixture of different types of radiations. The origin of the energy continuously released in radioactivity remained a complete mystery for a few years. The multiplicity of the radioactive substances became soon a difficult matter: what was real and what was induced ? Isotopy was still far ahead. It appeared that some radioactive substances had ''half-lifes'': were they genuine radioactive elements or was it just a transitory phenomenon ? Henri Becquerel (in 1900) and Pierre and Marie Curie (in 1902) hesitated on the correct answer. Only after Ernest Rutherford and Frederick Soddy established that radioactivity was the transmutation of one element into another, could one understand that a solid element transformed into a gaseous element, which in turn transformed itself into a succession of solid radioactive elements. It was only in 1913 - after the discovery of the atomic nucleus -, through precise measurements of X ray spectra, that Henry Moseley showed that the number of electrons of a given atom - and the charge of its nucleus - was equal to its atomic number in the periodic table. (authors)

X rays and radioactivity: a complete surprise

Energy Technology Data Exchange (ETDEWEB)

Radvanyi, P. [Laboratoire National Saturne, Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France); Bordry, M. [Institut du Radium, 75 - Paris (France)

1995-12-31

The discoveries of X rays and of radioactivity came as complete experimental surprises; the physicists, at that time, had no previous hint of a possible structure of atoms. It is difficult now, knowing what we know, to replace ourselves in the spirit, astonishment and questioning of these years, between 1895 and 1903. The nature of X rays was soon hypothesized, but the nature of the rays emitted by uranium, polonium and radium was much more difficult to disentangle, as they were a mixture of different types of radiations. The origin of the energy continuously released in radioactivity remained a complete mystery for a few years. The multiplicity of the radioactive substances became soon a difficult matter: what was real and what was induced ? Isotopy was still far ahead. It appeared that some radioactive substances had ``half-lifes``: were they genuine radioactive elements or was it just a transitory phenomenon ? Henri Becquerel (in 1900) and Pierre and Marie Curie (in 1902) hesitated on the correct answer. Only after Ernest Rutherford and Frederick Soddy established that radioactivity was the transmutation of one element into another, could one understand that a solid element transformed into a gaseous element, which in turn transformed itself into a succession of solid radioactive elements. It was only in 1913 - after the discovery of the atomic nucleus -, through precise measurements of X ray spectra, that Henry Moseley showed that the number of electrons of a given atom - and the charge of its nucleus - was equal to its atomic number in the periodic table. (authors).

The application of the German reg. guides ('elements of calculation') for radioactive discharges via exhaust air and waste water on fuel element fabrication

International Nuclear Information System (INIS)

Hille, R.; Rudolph, W.

1978-01-01

The fuel element fabricating plants at Hanau are handlung uranium, plutonium and thorium. The process essentially of converting these heavy metals into oxide, carbide or metal compounds. Thereby occur radioactive discharges into the exhaust air and the waste water. The most important pathway for exposure from these substances is inhalation, the released radionuclides mostly being α-emitters. Compared to this the external irradiation from immersion in γ, β, and neutron radiation is of less importance. (orig./HP) [de

Deposition of radioactive corrosion products on the internal surfaces of tube elements in gaseous phase of dissociating system N2O4 reversible 2NO2 reversible 2NO+O2

International Nuclear Information System (INIS)

Gol'tsev, V.P.; Dolgov, V.M.; Katanaev, A.O.

1979-01-01

Analysis of experimental data, obtained as a result of γ-scanning of tube element samples of loop assembling with dissociating coolant contacting with N 2 O 4 gaseous phase is presented. Radioactive depositions are differentiated on fixed and unfixed ones by the method of radiochemical analysis. The data obtained have made it possible to establish the analytical form of radioactive element distribution functions along the piping length. It is noted, that relative quantities of radioactive isotopes, existing in fixed and unfixed depositions vary with temperature. The fraction of soluble forms of corrosion radioactive products in unfixed depositions increases both with the decrease of temperature and after passing of radioactive impurity through the zone of liquid coolant

Study on the dynamics of halogen elements in the agro-environment and these element`s deficiency, toxicity and environmental hazards by the application of the neutron activation analysis method

Energy Technology Data Exchange (ETDEWEB)

Yuita, Kouichi [National Inst. of Agro-Environmental Sciences, Tsukuba, Ibaraki (Japan)

1998-03-01

A neutron activation analysis method is an accurate and highly sensitive method for analyzing halogen elements (iodine, bromine and chlorine) except fluorine. It is unsubstitutable and valuable method especially for iodine (including radioactive {sup 129}I) and bromine which are present at lower levels. Halogen elements have high chemical and physiological activities and move widely in the environment. As a result, deficiency and an excess of halogen elements in plants and animals have occurred and artificial halogen compounds have caused environmental pollution in wide areas. We efficiently utilized the neutron activation analysis method and an activable tracer method to obtain valuable findings which contribute to the clarification of and measures against these actual problems and which are also concerned with the occurrence, distribution and migration of halogen elements in the environment, especially agricultural and forestry ecosystems in space and in time. (author)

Pyrometallurgical partitioning of uranium and transuranic elements from rare earth elements by electrorefining and reductive extraction

International Nuclear Information System (INIS)

Uozumi, Koichi; Kinoshita, Kensuke; Inoue, Tadashi; Storvick, T.S.; Krueger, C.L.; Nabelek, C.R.

2001-01-01

High-level liquid waste generated from PUREX reprocessing contains a small amount of transuranic elements, such as Np, Pu, Am, and Cm, with long-lived radioactivities. A pyrometallurgical partitioning process is being developed to recover transuranic elements from such waste. Small amounts of U contained in the high-level liquid waste are also recovered in the process. A key issue for developing the process is effective separation of U and the transuranic elements from the rare-earth elements, because the two elemental groups are chemically analogous. A series of process tests were carried out in the present study to demonstrate that a combination of electrorefining and reductive extraction is useful for separating U and transuranic elements from the rare-earth elements. The results indicate that 99% of U and each transuranic elements is recovered by the combination process as a product, and that the quantity of rare-earth elements contained in the product is smaller than the transuranic elements by weight. The overall mass balance of U and transuranic elements in the system ranged within the experimental errors assigned to sampling and analysis. (author)

EDXRF applied to the chemical element determination of small invertebrate samples

Energy Technology Data Exchange (ETDEWEB)

Magalhaes, Marcelo L.R.; Santos, Mariana L.O.; Cantinha, Rebeca S.; Souza, Thomas Marques de; Franca, Elvis J. de, E-mail: marcelo_rlm@hotmail.com, E-mail: marianasantos_ufpe@hotmail.com, E-mail: rebecanuclear@gmail.com, E-mail: thomasmarques@live.com.pt, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

2015-07-01

Energy Dispersion X-Ray Fluorescence - EDXRF is a fast analytical technique of easy operation, however demanding reliable analytical curves due to the intrinsic matrix dependence and interference during the analysis. By using biological materials of diverse matrices, multielemental analytical protocols can be implemented and a group of chemical elements could be determined in diverse biological matrices depending on the chemical element concentration. Particularly for invertebrates, EDXRF presents some advantages associated to the possibility of the analysis of small size samples, in which a collimator can be used that directing the incidence of X-rays to a small surface of the analyzed samples. In this work, EDXRF was applied to determine Cl, Fe, P, S and Zn in invertebrate samples using the collimator of 3 mm and 10 mm. For the assessment of the analytical protocol, the SRM 2976 Trace Elements in Mollusk produced and SRM 8415 Whole Egg Powder by the National Institute of Standards and Technology - NIST were also analyzed. After sampling by using pitfall traps, invertebrate were lyophilized, milled and transferred to polyethylene vials covered by XRF polyethylene. Analyses were performed at atmosphere lower than 30 Pa, varying voltage and electric current according to the chemical element to be analyzed. For comparison, Zn in the invertebrate material was also quantified by graphite furnace atomic absorption spectrometry after acid treatment (mixture of nitric acid and hydrogen peroxide) of samples have. Compared to the collimator of 10 mm, the SRM 2976 and SRM 8415 results obtained by the 3 mm collimator agreed well at the 95% confidence level since the E{sub n} Number were in the range of -1 and 1. Results from GFAAS were in accordance to the EDXRF values for composite samples. Therefore, determination of some chemical elements by EDXRF can be recommended for very small invertebrate samples (lower than 100 mg) with advantage of preserving the samples. (author)

Biological cycles of radioactive contaminants

International Nuclear Information System (INIS)

Michon, M.-G.

1959-01-01

Artificial radio-elements (synthesized for scientific or industrial purposes)having been released, may be absorbed by plants or animals, and may eventually involve a catenation of organisms as some feed on the others. All organisms living in a polluted river become more radioactive than the water, which was to be expected, in as much as organisms are hypertonic in respect to sweet water. Conversely, soil brings into play physico-chemical phenomena (absorption) such that plants can get only a small portion of contaminating radio-elements, land animal feeding on such plants are relatively less exposed to contamination, and carnivorous animals feeding on herbivorous are still less exposed. Man, notably is fairly well protected, whereas lower organisms, notably unicellular organisms may suffer (mutations..). Reprint of a paper published in 'Revue de Pathologie Generale et de Physiologie Clinique', n. 707, April 1959, p. 505-514 [fr

Transfer of radioactive and chemical pollutants into irrigated rice fields

International Nuclear Information System (INIS)

Myttenaere, C.; Mousny, J.-M.; Dabin, P.; Bittel, R.

1975-01-01

In a general study on the consequences of radioactive and chemical releases in continental waters, flooded rice fields must be considered as a very important ecosystem due to the very large quantities of water used. In order to approach as much as possible to the natural conditions (irrigated rice fields of Northern Italy) ''mini-rice fields'' were built and local practices were respected. The behavior of activation and fission products ( 137 Cs, 60 Co, 65 Zn, 51 Cr...) and heavy metals pollutants (Cd, Cr, Sn) was studied and the transfer from water to soil and plant was followed. Concentration factors were calculated for the different organs of the plant and the impact of rice ingested to the dose delivered to man was evaluated [fr

Radioactivity in Trinitite six decades later

International Nuclear Information System (INIS)

Parekh, Pravin P.; Semkow, Thomas M.; Torres, Miguel A.; Haines, Douglas K.; Cooper, Joseph M.; Rosenberg, Peter M.; Kitto, Michael E.

2006-01-01

The first nuclear explosion test, named the Trinity test, was conducted on July 16, 1945 near Alamogordo, New Mexico. In the tremendous heat of the explosion, the radioactive debris fused with the local soil into a glassy material named Trinitite. Selected Trinitite samples from ground zero (GZ) of the test site were investigated in detail for radioactivity. The techniques used included α spectrometry, high-efficiency γ-ray spectrometry, and low-background β counting, following the radiochemistry for selected radionuclides. Specific activities were determined for fission products ( 9 Sr, 137 Cs), activation products ( 6 Co, 133 Ba, 152 Eu, 154 Eu, 238 Pu, 241 Pu), and the remnants of the nuclear fuel ( 239 Pu, 24 Pu). Additionally, specific activities of three natural radionuclides ( 4 K, 232 Th, 238 U) and their progeny were measured. The determined specific activities of radionuclides and their relationships are interpreted in the context of the fission process, chemical behavior of the elements, as well as the nuclear explosion phenomenology

Natural radioactivity and Rare Earth elements in feldspar samples, Central Eastern desert, Egypt

International Nuclear Information System (INIS)

Walley El-Dine, Nadia; El-Shershaby, Amal; Afifi, Sofia; Sroor, Amany; Samir, Eman

2011-01-01

The pegmatite bodies of the Eastern Desert of Egypt are widely distributed especially along the Marsa-Alam-Idfu road. The Abu Dob area covers about 150 km 2 of the Arabian Nubian shield at the central part of the Eastern Desert of Egypt. Most of the pegmatite is zoned; the zonation starts with milky quartz at the core followed by alkali feldspar at the margins. The feldspars vary in color from rose to milky and in composition from K-feldspar to Na-feldspar, sometimes interactions of both types are encountered. Thirteen feldspar samples were collected from different locations in the Abu Dob area for measuring the natural radioactivity of 238 U, 232 Th and 40 K using an HPGe detector. The variation in concentration of radionuclides for the area under investigation can be classified into regions of high, medium and low natural radioactivity. The average concentration in BqKg -1 has been observed to be from 9.5 to 183675.7 BqKg -1 for 238 U, between 6.1 and 94,314.2 BqKg -1 for 232 Th and from 0 to 7894.6 BqKg -1 for 40 K. Radium equivalent activities (Ra eq ), dose rate (D R ) and external hazard (H ex ) have also been determined. In the present work, the concentration of rare earth elements are measured for two feldspar samples using two techniques, Environmental Scanning Electron microscope XIL 30 ESEM, Philips, and Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The existence of rare earth elements in this area are very high and can be used in different important industries.

Natural radioactivity and Rare Earth elements in feldspar samples, Central Eastern desert, Egypt

Energy Technology Data Exchange (ETDEWEB)

Walley El-Dine, Nadia, E-mail: nadia_walley5@hotmail.co [Department of physics, Faculty of girls for Art, Science and Education, Ain Shams University, Heliopolis, Cairo (Egypt); El-Shershaby, Amal [Department of physics, Faculty of girls for Art, Science and Education, Ain Shams University, Heliopolis, Cairo (Egypt); Afifi, Sofia [Nuclear Materials Authority (Egypt); Sroor, Amany; Samir, Eman [Department of physics, Faculty of girls for Art, Science and Education, Ain Shams University, Heliopolis, Cairo (Egypt)

2011-05-15

The pegmatite bodies of the Eastern Desert of Egypt are widely distributed especially along the Marsa-Alam-Idfu road. The Abu Dob area covers about 150 km{sup 2} of the Arabian Nubian shield at the central part of the Eastern Desert of Egypt. Most of the pegmatite is zoned; the zonation starts with milky quartz at the core followed by alkali feldspar at the margins. The feldspars vary in color from rose to milky and in composition from K-feldspar to Na-feldspar, sometimes interactions of both types are encountered. Thirteen feldspar samples were collected from different locations in the Abu Dob area for measuring the natural radioactivity of {sup 238}U, {sup 232}Th and {sup 40}K using an HPGe detector. The variation in concentration of radionuclides for the area under investigation can be classified into regions of high, medium and low natural radioactivity. The average concentration in BqKg{sup -1} has been observed to be from 9.5 to 183675.7 BqKg{sup -1} for {sup 238}U, between 6.1 and 94,314.2 BqKg{sup -1} for {sup 232}Th and from 0 to 7894.6 BqKg{sup -1} for {sup 40}K. Radium equivalent activities (Ra{sub eq}), dose rate (D{sub R}) and external hazard (H{sub ex}) have also been determined. In the present work, the concentration of rare earth elements are measured for two feldspar samples using two techniques, Environmental Scanning Electron microscope XIL 30 ESEM, Philips, and Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The existence of rare earth elements in this area are very high and can be used in different important industries.

Radioactivity of heavy minerals and geochemistry of trace elements and radon, resulting from the weathering of the ophiolitic complex, Northwest of Syria

International Nuclear Information System (INIS)

Kattaa, B.; Al-Hilal, M.; Jubeli, Y.

1999-06-01

Geochemical and radiometric survey of stream sediments resulting from the weathering of ophiolitic complex at Al-Basit area were carried out. Several exploration techniques have been used to evaluate the radioactive elements and minerals in the area, and to estimate the significance of the radioactivity of the source rocks of these elements and minerals. determination of radioelements and some trace elements in stream sediments, in addition to gamma-ray spectrometry and radon gas measurement in water of springs and wells were carried out in the study area. The results show that the high values of radioactive elements and radon concentration are related to the occurrence of syenite nepheline and plageogranite, characterized by higher content of these elements compared to mafic and ultramafic rocks. Mineralogical study of the heavy minerals shows that the abundant minerals are pyroxene and amphibole, while less abundant minerals are iron oxides (limonite and hematite), chromite, ilmenite, olivine and magnetite. Rare minerals are zircon, apatite, barite, tourmaline and sphen. The absence of monazite, xenotime and thorite in the collected samples is mainly attributed to the very limited occurrence of their source rocks. However, this results is rather restricted to the collected samples. High concentration of magnetite and ilmenite in some samples was noted, in addition to the presence of mineral called galaxite which was not reported previously. Gold flake was also found in one of the samples. The study of grain morphology suggests that the heavy minerals were transported for short distance from their source rocks. Grain size analyse of heavy minerals reveals that the concentration of economic minerals such as chromite and ilmenite increases with the decrease of the grain size. (author)

Radioactive elements definition in composition of snake venom

International Nuclear Information System (INIS)

Mekhrabova, M.A.; Topchieva, Sh.F.; Abiev, G.A.; Nagiev, Dj.A.

2010-11-01

Full text: The given article presents questions concerned to usage of snake venom in medicine and pharmacy for medicinal drugs production, zootoxin base antidotes, thorough treatment of many deseases, especially onkological, also have a widespread in biology as a specific test-material for biological sistem analises. It is experimentally proved that certain amount of snake venom can replace morphine drugs, taking into acount that snake venom solutions make longer prolonged influence than other drugs, vithout causing an accustoming. It is also marked about possibility of usage of snake venom for cancer treatment. Many expeditions had been conducted with the purpose to research snake venom crytals on the territory of Azerbaijan. During these expeditions snakes capturing had been made with the purpose of taking the venom and also soil samples had been taken in order to research the quantity of radioactive elements. Measurements made with the help of electronic microscope C anberra . Revealed uranium activity in spectrum of venom as a result of radiation background, which appears under influence of ionizing radiation on the environment. On the base of analises data it can be ascertained that snake venom can be used for production of medicinal and also other necessary drugs. [ru

Phosphogypsum analysis: total content and extractable element concentrations

International Nuclear Information System (INIS)

Gennari, Roseli F.; Medina, Nilberto H.; Garcia, Isabella; Silveira, Marcilei A.G.

2011-01-01

Phosphogypsum stand for the chemical origin gypsum generated in fertilizers production, in which phosphate rock is attacked by sulfuric acid resulting in phosphoric acid (H 3 PO 4 ) and phosphate fertilizers. Phosphogypsum is not a commercial product and it is stocked in large open areas or accumulated in lakes inducing to a major environmental problem due to the presence of toxic and radioactive elements. The increasing world agricultural demand is the real responsible for the severity of this environmental problem. Nevertheless, there are some possibilities for the application of this reject material, such as civil construction, waste water treatment, and in cultivated lands, etc. In the agriculture the phosphogypsum is commonly used as a nutrient source due to its large amounts of phosphorus, calcium and sulfur. However, there are still some environmental questions related to the use of this by-product since phosphogypsum is classified as TENORM (Technologically Enhanced Naturally Occurring Radioactive Material), which is a solid waste containing heavy metals and naturally occurring radioactive elements from the rock matrix. In this work, Plasma Mass Spectrometry (ICP-MS) was used to study phosphogypsum samples. Several acid solutions for samples digestion were evaluated in order to be feasible the chemical analysis. BCR sequential extractions were also performed. The results showed analyte concentrations are highly dependent on the acid solution used. The BCR guidelines could not be applied as used for soil, since the phosphogypsum solubility is different. So, it would be necessary to use different mass aliquots in the extractions, to be feasible an environmental evaluation. (author)

Electronic tongue - an array of non-specific chemical sensors - for analysis of radioactive solutions

International Nuclear Information System (INIS)

Legin, A.; Rudnitskaya, A.; Babain, V.

2006-01-01

Multisensor systems, combining chemical sensor arrays with multivariate data processing engines (electronic tongue) rapidly and successfully developing in the last years are capable of simultaneous quantitative analysis of several species, e.g. metals, in complex real solutions. The expansion of the metals (metal ions) and species to be detected in radioactive waste requires permanent enhancement of sensing materials and sensors, with seriously different properties from those known earlier. A prospective direction of R and D of novel sensing materials is exploitation of radiochemical extraction systems and application of extraction substances as active components of new sensors. The sensors based on bidentate phosphorous organic compounds and their combinations with chlorinated cobalt dicarbollide displayed high sensitivity and selectivity to rare-earth metal ions La 3+ , Pr 3+ , Nd 3+ , Eu 3+ . The results indicated good promise for the development of novel analytical tools for detection of multivalent metal cations in different media, particularly in corrosive solutions such as radioactive wastes and solutions derived from spent nuclear fuel. The sensors and sensor arrays made on their basis can play an important role in the development of 'electronic tongue' systems for rapid analytical determinations of different components in complex radioactive solutions

Immobilization of simulated radioactive soil waste containing cerium by self-propagating high-temperature synthesis

International Nuclear Information System (INIS)

Mao, Xianhe; Qin, Zhigui; Yuan, Xiaoning; Wang, Chunming; Cai, Xinan; Zhao, Weixia; Zhao, Kang; Yang, Ping; Fan, Xiaoling

2013-01-01

A simulated radioactive soil waste containing cerium as an imitator element has been immobilized by a thermite self-propagating high-temperature synthesis (SHS) process. The compositions, structures, and element leaching rates of products with different cerium contents have been characterized. To investigate the influence of iron on the chemical stability of the immobilized products, leaching tests of samples with different iron contents with different leaching solutions were carried out. The results showed that the imitator element cerium mainly forms the crystalline phases CeAl 11 O 18 and Ce 2 SiO 5 . The leaching rate of cerium over a period of 28 days was 10 −5 –10 −6 g/(m 2 day). Iron in the reactants, the reaction products, and the environment has no significant effect on the chemical stability of the immobilized SHS products

Immobilization of simulated radioactive soil waste containing cerium by self-propagating high-temperature synthesis

Science.gov (United States)

Mao, Xianhe; Qin, Zhigui; Yuan, Xiaoning; Wang, Chunming; Cai, Xinan; Zhao, Weixia; Zhao, Kang; Yang, Ping; Fan, Xiaoling

2013-11-01

A simulated radioactive soil waste containing cerium as an imitator element has been immobilized by a thermite self-propagating high-temperature synthesis (SHS) process. The compositions, structures, and element leaching rates of products with different cerium contents have been characterized. To investigate the influence of iron on the chemical stability of the immobilized products, leaching tests of samples with different iron contents with different leaching solutions were carried out. The results showed that the imitator element cerium mainly forms the crystalline phases CeAl11O18 and Ce2SiO5. The leaching rate of cerium over a period of 28 days was 10-5-10-6 g/(m2 day). Iron in the reactants, the reaction products, and the environment has no significant effect on the chemical stability of the immobilized SHS products.

Optimization and validation of a chemical process for uranium, mercury and cesium leaching from cemented radioactive wastes

Energy Technology Data Exchange (ETDEWEB)

Reynier, N.; Lastra, R.; Laviolette, C.; Bouzoubaa, N., E-mail: nicolas.reynier@canada.ca [Natural Resources Canada, CanmetMINING, Ottawa, Ontario (Canada); Chapman, M. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada)

2015-12-15

Canadian Nuclear Laboratories (CNL) is developing a treatment and long-term management strategy for a legacy cemented radioactive waste that contains uranium, mercury, and fission products. Extracting the uranium would be advantageous for decreasing the waste classification and reducing the cost of long-term management. The chemical leachability of 3 key elements (U, Hg, and Cs) from a surrogate cemented waste (SCW) was studied with several lixiviants. The results showed that the most promising approach to leach and recover U, Hg, and Cs is the direct leaching of the SCW with H{sub 2}SO{sub 4} in strong saline media. Operating parameters such as particle size, temperature, pulp density, leaching time, acid and salt concentrations, number of leaching/washing steps, etc. were optimized to improve key elements solubilization. Sulfuric leaching in saline media of a SCW (U5) containing 1182 ppm of U, 1598 ppm of Hg, and 7.9 ppm of Cs in the optimized conditions allows key elements solubilisation of 98.5 ± 0.4%, 96.6 ± 0.1%, and 93.8 ± 1.1% of U, Hg, and Cs, respectively. This solubilization process was then applied in triplicate to 7 other SCWs prepared with different cements, liquid ratios, and at different aging times and temperatures. Concentrated sulfuric acid is added to the slurry until the pH is about 2, which causes the complete degradation of cement and the formation of CaSO{sub 4}. Sulfuric acid is particularly useful because it produces a leachate that is amenable to conventional ion exchange technology for the separation and recovery of uranium. (author)

Rehabilitation of radioactive objects of Kirovo-Chepetsky chemical plant preliminary program of works

International Nuclear Information System (INIS)

Chesnokov, F.V.; Ivanov, O.P.; Pavlenko, V.I.; Semenov, S.G.; Stepanov, V.E.; Volkov, V.G.; Volkovich, A.G.; Zverkov, Yu.A.

2008-01-01

In 2007, the specialists of RRC Kurchatov Institute, jointly with MosNPO Radon, launched works on the radiation survey of radiation-contaminated objects and areas on the site of Kirovo-Chetetsky Chemical Plant (KCCP). This survey was launched with the object of subsequent development of the rehabilitation program and concept for buildings and storage sites left from shutdown uranium-processing facilities, as well as for sludge storage facilities and repositories of radioactive waste produced as a result of these facilities operation. Besides, radioactive contamination caused by the preceding operations involving radwaste and equipment contaminated at early stages of uranium hexafluoride (UHF) and tetrafluoride (UTF) processing technology mastering was detected in some spots at KCCP site. The radiation survey was performed in order to assess the amount of rehabilitation works, to identify the most critical objects and areas at KCCP site, and to develop the sequence of measures to be implemented in order to enhance the radiation safety of people living in the Kirov Region. (author)

Element analysis and radioactivity measurement within a wood disk by neutron activation analysis

International Nuclear Information System (INIS)

Hayashi, Y.; Ikeue, N.; Tanoi, K.; Tange, T.; Yagi, H.; Nakanishi, T.M.

2003-01-01

16 elements and the radioactivity of 210 Pb in a wood disk, across the annual rings have been analyzed to find out a promising tool for dendrochronology (chronology of wood) both for a Japanese wood, Cryptomeria japonica, and for an Indonesian rain forest wood, Alstonia, which does not form annual rings because of the relatively constant climate of the rain forest. As a result, only Mg concentration showed similar, smooth decreasing tendency in both wood species. The smooth change of the Mg concentration across the annual rings along with the growth suggested the possibility of the Mg concentration determination as a promising dendrochronological tool. (author)

Chemical Abundances of Hydrostatic and Explosive Alpha-elements in Sagittarius Stream Stars

Science.gov (United States)

Carlin, Jeffrey L.; Sheffield, Allyson A.; Cunha, Katia; Smith, Verne V.

2018-05-01

We analyze chemical abundances of stars in the Sagittarius (Sgr) tidal stream using high-resolution Gemini+GRACES spectra of 42 members of the highest surface-brightness portions of both the trailing and leading arms. Targets were chosen using a 2MASS+WISE color–color selection, combined with the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) radial velocities. In this Letter, we analyze [Fe/H] and α-elements produced by both hydrostatic (O, Mg) and explosive (Si, Ca, Ti) nucleosynthetic processes. The average [Fe/H] for our Sgr stream stars is lower than that for stars in the Sgr core, and stars in the trailing and leading arms show systematic differences in [Fe/H]. Both hydrostatic and explosive elements are depleted relative to Milky Way (MW) disk and halo stars, with a larger gap between the MW trend and Sgr stars for the hydrostatic elements. Chemical abundances of Sgr stream stars show similar patterns to those measured in the core of the Sgr dSph. We explore the ratio of hydrostatic to explosive α-elements [α h/ex] (which we refer to as the “HEx ratio”). Our observed HEx ratio trends for Sgr debris are deficient relative to MW stars. Via simple chemical evolution modeling, we show that these HEx ratio patterns are consistent with a Sgr IMF that lacks the most massive stars. This study provides a link between the chemical properties in the intact Sgr core and the significant portion of the Sgr system’s luminosity that is estimated to currently reside in the streams.

Isotope-abundance variations and atomic weights of selected elements: 2016 (IUPAC Technical Report)

Science.gov (United States)

Coplen, Tyler B.; Shrestha, Yesha

2016-01-01

There are 63 chemical elements that have two or more isotopes that are used to determine their standard atomic weights. The isotopic abundances and atomic weights of these elements can vary in normal materials due to physical and chemical fractionation processes (not due to radioactive decay). These variations are well known for 12 elements (hydrogen, lithium, boron, carbon, nitrogen, oxygen, magnesium, silicon, sulfur, chlorine, bromine, and thallium), and the standard atomic weight of each of these elements is given by IUPAC as an interval with lower and upper bounds. Graphical plots of selected materials and compounds of each of these elements have been published previously. Herein and at the URL http://dx.doi.org/10.5066/F7GF0RN2, we provide isotopic abundances, isotope-delta values, and atomic weights for each of the upper and lower bounds of these materials and compounds.

SRS: Site ranking system for hazardous chemical and radioactive waste

International Nuclear Information System (INIS)

Rechard, R.P.; Chu, M.S.Y.; Brown, S.L.

1988-05-01

This report describes the rationale and presents instructions for a site ranking system (SRS). SRS ranks hazardous chemical and radioactive waste sites by scoring important and readily available factors that influence risk to human health. Using SRS, sites can be ranked for purposes of detailed site investigations. SRS evaluates the relative risk as a combination of potentially exposed population, chemical toxicity, and potential exposure of release from a waste site; hence, SRS uses the same concepts found in a detailed assessment of health risk. Basing SRS on the concepts of risk assessment tends to reduce the distortion of results found in other ranking schemes. More importantly, a clear logic helps ensure the successful application of the ranking procedure and increases its versatility when modifications are necessary for unique situations. Although one can rank sites using a detailed risk assessment, it is potentially costly because of data and resources required. SRS is an efficient approach to provide an order-of-magnitude ranking, requiring only readily available data (often only descriptive) and hand calculations. Worksheets are included to make the system easier to understand and use. 88 refs., 19 figs., 58 tabs

A method for conditioning radioactive-wastes

International Nuclear Information System (INIS)

Cuaz, Daniel; Thiery, Daniel.

1974-01-01

Description is given of a method for conditioning radioactive-wastes, according to the main patent. This method is characterized in that the radioactive wastes are constituted by radio-elements incorporated with filtration and/or floculation promoters. This can be applied to radioactive effluent processing [fr

Annual Report, Fall 2016: Alternative Chemical Cleaning of Radioactive High Level Waste Tanks - Corrosion Test Results

International Nuclear Information System (INIS)

Wyrwas, R. B.

2016-01-01

The testing presented in this report is in support of the investigation of the Alternative Chemical Cleaning program to aid in developing strategies and technologies to chemically clean radioactive High Level Waste tanks prior to tank closure. The data and conclusions presented here were the examination of the corrosion rates of A285 carbon steel and 304L stainless steel exposed to two proposed chemical cleaning solutions: acidic permanganate (0.18 M nitric acid and 0.05M sodium permanganate) and caustic permanganate. (10 M sodium hydroxide and 0.05M sodium permanganate). These solutions have been proposed as a chemical cleaning solution for the retrieval of actinides in the sludge in the waste tanks, and were tested with both HM and PUREX sludge simulants at a 20:1 ratio.

Annual Report, Fall 2016: Alternative Chemical Cleaning of Radioactive High Level Waste Tanks - Corrosion Test Results

Energy Technology Data Exchange (ETDEWEB)

Wyrwas, R. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-09-01

The testing presented in this report is in support of the investigation of the Alternative Chemical Cleaning program to aid in developing strategies and technologies to chemically clean radioactive High Level Waste tanks prior to tank closure. The data and conclusions presented here were the examination of the corrosion rates of A285 carbon steel and 304L stainless steel exposed to two proposed chemical cleaning solutions: acidic permanganate (0.18 M nitric acid and 0.05M sodium permanganate) and caustic permanganate. (10 M sodium hydroxide and 0.05M sodium permanganate). These solutions have been proposed as a chemical cleaning solution for the retrieval of actinides in the sludge in the waste tanks, and were tested with both HM and PUREX sludge simulants at a 20:1 ratio.

Glove box operations for transplutonium element production

International Nuclear Information System (INIS)

Knauer, J.B.; Alexander, C.W.; Wiggins, J.T.

1986-01-01

Glove boxes are used in the Transuranium Processing Plant (TRU) at Oak Ridge National Laboratory for (1) completing the final chemical processing steps to isolate and purify the transplutonium elements, (2) packaging transplutonium elements for shipment, (3) preirradiation and postirradiation processing of samples used to produce special transplutonium isotopes in the High Flux Isotope Reactor (HFIR), and (4) conducting special projects, which include providing highly purified transplutonium products in special chemical forms and/or in experimental devices as requested by researchers. During 20 years of operation, the quantities of transplutonium elements produced, and thus the amount of radioactivity handled, have continually increased. At the same time, substantial effort has been expended to reduce personnel radiation exposures. Equipment and techniques have been developed to maintain the desired operational capabilities in the glove boxes while keeping radiation exposures to operating personnel as low as reasonably achievable. Developments have included the design and fabrication of product handling and collection devices, product storage containers, and laminated exterior shields of lead glass, lead acrylic, acrylic sheets, polyethylene, and lead

Pharmacological study of radioactive-gold colloid transport by blood and by serous exudate

International Nuclear Information System (INIS)

Rousselet, J.

1966-06-01

After giving the essential physico-chemical properties of the colloids, the author considers the biological role of these substances and, in connection with their transport by the blood, their capture by elements of the reticula-endothelial system. A summary is given of present knowledge concerning the role of serous proteins in the transport of substances, particularly that of radio-active colloidal gold. The blood fractions which can take part in colloidal gold transport are the red blood corpuscles, the leukocytes and histiocytic elements as well as the plasma. The radioactive distribution in these various fractions is obtained by autoradiography of blood sediments. After showing the importance of the role of the plasma in radioactive particle transport, the author, describes the attempts made to detect a possible of colloidal gold 198 on the various serous proteins using various methods of separation. The ''in vitro'' and ''in vivo'' bonds between colloidal gold-198 particles and either the serous proteins or healthy specimens or the effusion liquids of pathological origin in man, or due to an experimental inflammation with carregenin in the rat, have been studied. The bonding appears to be effective because of the protective macromolecular layer formed by the gelatine. The different positions of the colloidal grains on the electrophoregram can only be explained by their different physico-chemical characteristics. Gold in the ionic form, on the other hand, is combined only with the albumen is the amount metal present does not exceed a certain value. (author) [fr

Chemical toxicity and radioactivity of depleted uranium: The evidence from in vivo and in vitro studies.

Science.gov (United States)

Asic, Adna; Kurtovic-Kozaric, Amina; Besic, Larisa; Mehinovic, Lejla; Hasic, Azra; Kozaric, Mirza; Hukic, Mirsada; Marjanovic, Damir

2017-07-01

The main aim of this review is to summarize and discuss the current state of knowledge on chemical toxicity and radioactivity of depleted uranium (DU) and their effect on living systems and cell lines. This was done by presenting a summary of previous investigations conducted on different mammalian body systems and cell cultures in terms of potential changes caused by either chemical toxicity or radioactivity of DU. In addition, the authors aimed to point out the limitations of those studies and possible future directions. The majority of both in vitro and in vivo studies performed using animal models regarding possible effects caused by acute or chronic DU exposure has been reviewed. Furthermore, exposure time and dose, DU particle solubility, and uranium isotopes as factors affecting the extent of DU effects have been discussed. Special attention has been dedicated to chromosomal aberrations, DNA damage and DNA breaks, as well as micronuclei formation and epigenetic changes, as DU has recently been considered a possible causative factor of all these processes. Therefore, this approach might represent a novel area of study of DU-related irradiation effects on health. Since different studies offer contradictory results, the main aim of this review is to summarize and briefly discuss previously obtained results in order to identify the current opinion on DU toxicity and radioactivity effects in relation to exposure type and duration, as well as DU properties. Copyright © 2017 Elsevier Inc. All rights reserved.

Allium -test as a tool for toxicity testing of environmental radioactive-chemical mixtures

International Nuclear Information System (INIS)

Oudalova, A A; Pyatkova, S V; Geras’kin, S A; Dikareva, N S

2017-01-01

Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium -test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium -test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds. (paper)

A pilot-scale radioactive test using in situ vitrification

International Nuclear Information System (INIS)

Timmerman, C.L.; Oma, K.M.

1985-01-01

Pacific Northwest Laboratory is developing in situ vitrification (ISV) as a potential remedial action technique for previously disposed radioactive liquid drain sites. The process melts the contaminated soil to produce a durable glass and crystalline waste form and encapsulates the radionuclides. The development of this alternative technology is being performed for the US Department of Energy. The results of an ISV pilot-scale test conducted in June 1983 are discussed in which soils contaminated with actual radioactive transuranic and mixed fission product elements were vitrified. The test successfully demonstrated the containment of radionuclides during processing, both within the vitrified mass and in the off-gas system. No environmental release of radioactive material was detectable during testing operations. The vitrified soil retained >99% of all radionuclides. Losses to the offgas system varied from less than or equal to 0.03% for particulate materials (plutonium and strontium) to 0.8% for cesium, which is a more volatile element. The off-gas system effectively contained both volatile and entrained radioactive materials. Analysis of the vitrified soil revealed that all radionuclides were distributed throughout the vitrified zone, some more uniformly than others. Analysis of soil samples taken adjacent to the block indicated that no migration of radionuclides outside the vitrification zone occurred. Leaching studies have shown that the ISV process generates a highly durable waste form, comparable to Pyrex and granite. Based on geologic data from the hydration of obsidian, which is chemically similar to the ISV glass, the hydration or weathering rate is predicted to be much less than 1 mm in 10,000 yr

Algorithm for calculating an availability factor for the inhalation of radioactive and chemical materials

International Nuclear Information System (INIS)

1984-02-01

This report presents a method of calculating the availability of buried radioactive and nonradioactive materials via an inhalation pathway. Availability is the relationship between the concentration of a substance in the soil and the dose rate to a human receptor. Algorithms presented for calculating availabiliy of elemental inorganic substances are based on atmospheric enrichment factors; those presented for calculating availability of organic substances are based on vapor pressures. The basis, use, and limitations of the developed equations are discussed. 32 references, 5 tables

Genetic interpretations of elemental and chemical differences in a soil chronosequence, California

Science.gov (United States)

Harden, J.W.

1988-01-01

Soils developed on fluvial terraces in central California have similar parent materials, climatic settings, vegetation cover and slopes but range in age from 40,000 to 3,000,000 years. The soils have chemical compositions that change systematically with increasing age. Such chemical differentiation is most likely the result of long-term weathering and mineralogical transformations that occurred since deposition of terrace fills and stabilization of the geomorphic surfaces. The changes in composition with time closely mimic other studies on mineral weathering, in which alkali and alkali-earth elements are lost more rapidly than transitional elements. The relative rates of element loss were determined by changes in element ratios over time. Net losses and gains of elements in different size fractions were monitored by their concentrations relative to Zr, the most stable constituent. Both sand and finer size fractions have lost considerable amounts of Ca, Mg, Na and K. Aluminum appears to have been lost from the sand fraction and gained in the fine fraction over a 3-million-year-time-span. Although there is no evidence for losses of Fe and Ti from sands, there is a net influx of Fe and Ti into finer fractions, probably gained from undetectable yet significant weathering of sand grains. Etching of sand grains, clay mineralogy, and microprobe analyses also indicate that the soils have undergone these chemical transformations during their formation. Mineralogical analyses also mimic other studies on mineral weathering, in which the pyroxenes weather more rapidly than hornblende, which weathers more rapidly than sphene or zircon. ?? 1988.

Prompt gamma-ray spectroscopy and its use for the elemental chemical analysis

International Nuclear Information System (INIS)

Deconninck, G.; Demortier, G.; Bodart, F.

The elemental chemical analysis by nuclear techniques has been widely developed since a quarter of century. In this review the analysis by irradiation of the the sample (solid or liquid) of a majority of chemical elements by means of the charged particles and the detection during this irradiation of the gamma photons characteristic of the element are considered. After a brief account of the physical phenomena peculiar to the prompt detection of photons in comparison with the activation methods where a delayed activity is measured, a brief description of the experimental equipment for this kind of analysis is given. A comprehensive critical survey of the recent applications to the analysis of metals, semiconductors and electric insulating substances is presented. The necessary informations for the choice of the nuclear reaction to use for a specific analysis are contained in a set of tables. (AF)

Guidelines for generators of hazardous chemical waste at LBL and guidelines for generators of radioactive and mixed waste at LBL

International Nuclear Information System (INIS)

1991-09-01

In part one of this document the Governing Documents and Definitions sections provide general guidelines and regulations applying to the handling of hazardous chemical wastes. The remaining sections provide details on how you can prepare your waste properly for transport and disposal. They are correlated with the steps you must take to properly prepare your waste for pickup. The purpose of the second part of this document is to provide the acceptance criteria for the transfer of radioactive and mixed waste to LBL's Hazardous Waste Handling Facility (HWHF). These guidelines describe how you, as a generator of radioactive or mixed waste, can meet LBL's acceptance criteria for radioactive and mixed waste

Statistic analysis of grouping in evaluation of the behavior of stable chemical elements and physical-chemical parameters in effluent from uranium mining

International Nuclear Information System (INIS)

Pereira, Wagner de S.

2013-01-01

The Ore Treatment Unit (UTM) is a uranium mine off. The statistical analysis of clustering was used to evaluate the behavior of stable chemical elements and physico-chemical variables in their effluents. The use of cluster analysis proved effective in the evaluation, allowing to identify groups of chemical elements in physico-chemical variables and group analyzes (element and variables ). As a result, we can say, based on the analysis of the data, a strong link between Ca and Mg and between Al and TR 2 O 3 (rare earth oxides) in the UTM effluents. The SO 4 was also identified as strongly linked to total solids and dissolved and these linked to electrical conductivity. Other associations existed, but were not as strongly linked. Additional collections for seasonal evaluation are required so that assessments can be confirmed. Additional statistics analysis (ordination techniques) should be used to help identify the origins of the groups identified in this analysis. (author)

Chemical aspects of pellet-cladding interaction in light water reactor fuel elements

International Nuclear Information System (INIS)

Olander, D.R.

1982-01-01

In contrast to the extensive literature on the mechanical aspects of pellet-cladding interaction (PCI) in light water reactor fuel elements, the chemical features of this phenomenon are so poorly understood that there is still disagreement concerning the chemical agent responsible. Since the earliest work by Rosenbaum, Davies and Pon, laboratory and in-reactor experiments designed to elucidate the mechanism of PCI fuel rod failures have concentrated almost exclusively on iodine. The assumption that this is the reponsible chemical agent is contained in models of PCI which have been constructed for incorporation into fuel performance codes. The evidence implicating iodine is circumstantial, being based primarily upon the volatility and significant fission yield of this element and on the microstructural similarity of the failed Zircaloy specimens exposed to iodine in laboratory stress corrosion cracking (SCC) tests to cladding failures by PCI

Chemical composition and mineral elements of edible insects (at ...

African Journals Online (AJOL)

The Chemical Composition and Mineral Elements of two edible insects' larvae and termite soldiers were assayed. Their ash content were between 1.01% and 7.50%. The legless larva (LS) had 28.52% fat, while the solider ant had 7.14% and the Legged larva (LG) had 1.50%. The white ant (SA) had 15.61% protein while ...

Radioactive ores from Agostinho field, Pocos de Caldas (MG), Brazil

International Nuclear Information System (INIS)

Fujimori, K.

1974-01-01

Aiming to characterize the radioactive minerals of Campo Agostinho, Pocos de Caldas - Brazil, the survey of all natural radiactive elements and their geochemical behaviors, decays and radioactive equilibrium was done. Several models of radioactive instability of the minerals or the radioactive samples were proposed to characterize the geochemistry and the mineralization of radioactive elements. The complete isotopic analysis of the elements was done by high resolution gamma spectrometry, using a Ge(Li) detector, at the temperature of liquid nitrogen, coupled to a multichannel analyser. The sample in radioactive equilibrium of Atomic Energy Comission of United States - A.S. n.6, NBL - New Brunswick Laboratory, was considered as standard sample. Fluorite, zircons, pirite, molibinite, rutile, anatase, niobophyllite, and in small ratio (bellow 0.1%) uranothorianite, coffinite, pyrochlore, monazite and apatite. (M.C.K.) [pt

ELECTRONIC ANALOG COMPUTER FOR DETERMINING RADIOACTIVE DISINTEGRATION

Science.gov (United States)

Robinson, H.P.

1959-07-14

A computer is presented for determining growth and decay curves for elements in a radioactive disintegration series wherein one unstable element decays to form a second unstable element or isotope, which in turn forms a third element, etc. The growth and decay curves of radioactive elements are simulated by the charge and discharge curves of a resistance-capacitance network. Several such networks having readily adjustable values are connected in series with an amplifier between each successive pair. The time constant of each of the various networks is set proportional to the half-life of a corresponding element in the series represented and the charge and discharge curves of each of the networks simulates the element growth and decay curve.

Challenges in ensuring radiological safety and nuclear forensic for malicious acts involving nuclear and other radioactive material

International Nuclear Information System (INIS)

Sharma, Ranjit; Chatterjee, M.K.; Singh, Rajvir; Pradeepkumar, K.S.

2010-01-01

Nuclear and other radioactive materials may get smuggled into the country aimed at malicious acts. Radioactive material detected accidentally or during inspection at the entry points/national borders may indicate illicit trafficking for the purpose of nuclear/radiological terrorism. As country requires prevention and preparedness for response to these malicious acts, nuclear forensic techniques are to be developed incorporating radiological safety aspects. Nuclear forensics helps in determining the origin, intended use, legal owner and the smuggled route etc. by using fingerprinting as well as comparison with reference data. The suggested sequence of methods for analysis of radioactive material/samples will be radiological assessment, physical characterization, traditional forensic analysis, isotope analysis along with elemental/chemical analysis

Measurements of radon and chemical elements: Popocatepetl volcano; Mediciones de radon y elementos quimicos: Volcan Popocatepetl

Energy Technology Data Exchange (ETDEWEB)

Pena, P.; Segovia, N.; Lopez, B.; Reyes, A.V. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Armienta, M.A.; Valdes, C.; Mena, M. [IGFUNAM, Ciudad Universitaria, 04510 Mexico D.F. (Mexico); Seidel, J.L.; Monnin, M. [UMR 5569 CNRS Hydrosciences, Montpellier (France)

2002-07-01

The Popocatepetl volcano is a higher risk volcano located at 60 Km from Mexico City. Radon measurements on soil in two fixed seasons located in the north slope of volcano were carried out. Moreover the radon content, major chemical elements and tracks in water samples of three springs was studied. The radon of soil was determined with solid detectors of nuclear tracks (DSTN). The radon in subterranean water was evaluated through the liquid scintillation method and it was corroborated with an Alpha Guard equipment. The major chemical elements were determined with conventional chemical methods and the track elements were measured using an Icp-Ms equipment. The radon on soil levels were lower, indicating a moderate diffusion of the gas across the slope of the volcano. The radon in subterranean water shown few changes in relation with the active scene of the volcano. The major chemical elements and tracks showed a stable behavior during the sampling period. (Author)

Development of nuclear standard filter elements for PWR plant

International Nuclear Information System (INIS)

Weng Minghui; Wu Jidong; Gu Xiuzhang; Zhang Jinghua

1988-11-01

Model FRX-5 and FRX-10 nuclear standard filter elements are used for the fluid clarification of the chemical and volume control system (CVCS), boron recycle system (BRS), spent fuel pit cooling system (SFPCS) and steam generator blowdown system (SGBS) in Qinshan Nuclear Power Plant. The radioactive contaminant, fragment of resin and impurity are collected by these filter elements, The core of filter elements consists of polypropylene frames and paper filter medium bonded by resin. A variety of filter papers are tested for optimization. The flow rate and comprehensive performance have been measured in the simulation condition. The results showed that the performance and lifetime have met the designing requirements. The advantages of the filter elements are simple in manufacturing, less expense and facilities for waste-disposal. At present, some of filter elements have been produced and put in operation

Removal of some Fission Products from Low Level Liquid Radioactive Waste by Chemical Precipitation liquid/Co-precipitation / Phosphate Coagulant

International Nuclear Information System (INIS)

Borai, E.H.; Attallah, M.F.; Hilal, M.A.; Abo-Aly, M.M.; Shehata, F.A.

2008-01-01

In Egypt radioactive waste has been generated from various uses of radioactive materials. Presence of cesium demonstrated a major problem from the removal point of view even by conventional and advanced technologies. Selective chemical precipitation has been oriented for removal of some fission products including 137 Cs from low level liquid radioactive waste (LLLRW). The aim of the present study was focused to investigate the effectiveness of various phosphate compounds that improved the precipitation process and hence the decontamination factor. The results showed that, maximum removal of 137 Cs reaching 46.4 % using di-sodium hydrogen phosphate as a selective coagulant. It was found that significant enhancement of co-precipitation of 137 Cs (62.5 %) was obtained due to presence of Nd 3+ in the LLLRW

Radioactive zinc in soil-plant relationship studies

International Nuclear Information System (INIS)

Karimian, N.

1986-01-01

Zinc is one of the elements whose essentiality for plant growth and development has been proved beyond any doubt. Plant life and consequently the crop yield is impossible without zinc. The results of chemical, greenhouse, and field experiments on soils of Shiraz show that their level of available zinc for some crops is inadequate, despite the fact that the total amount of zinc in these soils may be relatively high. Obtaining the maximum yield, therefore, requires that either supplemental zinc be applied as chemical fertilizers or make the endogenous zinc more available to plants through some management practices. One of the isotopes of zinc, i.e. 65 Zn, is radioactive and has a detectable radiation which makes it suitable for tracer studies of zinc in soil, water, plant and animal. These studies help in understanding the soil plant relationships of zinc which in turn help to determine the optimum conditions of obtaining maximum yield. This paper presents and analyzes the results of some selected experiments to show different techniques of using radioactive zinc in understanding the behavior of zinc in soil and plant. Suggestions are also made of using this radioisotope in understanding the reactions of zinc in soils of Iran

Chemical elements contamination of snow cover in region of coal production 'Karazhyra'

International Nuclear Information System (INIS)

Evlampieva, E.P.; Panin, M.S.

2008-01-01

Peculiarities of space distribution of chemical elements in hardphase and water-soluble falls of snow cover in region of coal deposit 'Karazhyra' are investigated. The maximal, minimal and background areas of elements accumulation in the snow of this region and distribution of their cumulative rates are determined. The main pollutants of snow cover unto background level are revealed.

Evaluating chemical toxicity of surface disposal of LILW-SL in Belgium

International Nuclear Information System (INIS)

Mallants, D.; Wang, L.; Weetjens, E.; Cool, W.

2008-01-01

ONDRAF/NIRAS is developing and evaluating a surface disposal concept for low and intermediate level short-lived radioactive waste (LILW-SL) at Dessel (Belgium)). In support of ONDRAF/NIRAS's assignment, SCK/CEN carried out long-term performance assessment calculations for the inorganic non-radioactive components that are present in LILW-SL. This paper summarizes the results obtained from calculations that were done for a heavily engineered surface disposal facility at the nuclear zone of Mol/Dessel. The calculations address the migration of chemo-toxic elements from the disposed waste to groundwater. Screening calculations were performed first to decide which non-radioactive components could potentially increase concentrations in groundwater to levels above the groundwater standards. On the basis of very conservative calculations, only 6 out of 41 chemical elements could not be classified as having a negligible impact on man and environment. For each of these six elements (B, Be, Cd, Pb, Sb, and Zn), the source term was characterized in terms of its chemical form (i.e., metal, oxide, or salt), and a macroscopic transport model built that would capture the small-scale dissolution processes relevant to element release from a cementitious waste container. Furthermore, reliable transport parameters in support of the convection dispersion-retardation (CDR) transport calculations were determined. This included derivation of (1) solubility for a cementitious near field environment based on thermodynamic equilibrium calculations with The Geo-chemist's Workbench, and (2) distribution coefficients based on a compilation of literature values. Scoping calculations illustrated the effects of transport parameter uncertainty on the rates at which inorganic components in LILW-SL leach to groundwater. (authors)

Classification of radioactive waste

International Nuclear Information System (INIS)

1994-01-01

Radioactive wastes are generated in a number of different kinds of facilities and arise in a wide range of concentrations of radioactive materials and in a variety of physical and chemical forms. To simplify their management, a number of schemes have evolved for classifying radioactive waste according to the physical, chemical and radiological properties of significance to those facilities managing this waste. These schemes have led to a variety of terminologies, differing from country to country and even between facilities in the same country. This situation makes it difficult for those concerned to communicate with one another regarding waste management practices. This document revises and updates earlier IAEA references on radioactive waste classification systems given in IAEA Technical Reports Series and Safety Series. Guidance regarding exemption of materials from regulatory control is consistent with IAEA Safety Series and the RADWASS documents published under IAEA Safety Series. 11 refs, 2 figs, 2 tab

What are Spent Nuclear Fuel and High-Level Radioactive Waste?

International Nuclear Information System (INIS)

2002-01-01

Spent nuclear fuel and high-level radioactive waste are materials from nuclear power plants and government defense programs. These materials contain highly radioactive elements, such as cesium, strontium, technetium, and neptunium. Some of these elements will remain radioactive for a few years, while others will be radioactive for millions of years. Exposure to such radioactive materials can cause human health problems. Scientists worldwide agree that the safest way to manage these materials is to dispose of them deep underground in what is called a geologic repository

Geochemical behavior of long-lived radioactive wastes

International Nuclear Information System (INIS)

Gera, F.

1975-07-01

The hazard potential associated with the heavy elements present in high-level radioactive waste decreases greatly in the first few tens of thousands of years of decay; however, further reduction in the hazard potential becomes extremely slow after about 100,000 years. In the time period between 100,000 and 5 million years the hazard potential of high-level waste is reduced by a factor of between 10 and 20. Current evidence seems to indicate that if radioactive waste containment were to fail after a period of 100,000 years or more, some environmental contamination would result; however, the contamination levels would be low. The radiological risk would not be significantly different from that now existing in various localities as a result of the accumulation of natural radioactive elements. With the partial exception of radium, which is concentrated in the fruit of specific perennial plants, the long-lived alpha-emitters are characterized by very low biologic availability in terrestrial ecosystems. The biologic availability may be somewhat higher in aquatic ecosystems due to the significant reconcentration factors in particular organisms. Data concerning the levels of activity in foods grown on radioactive soils seem to confirm the low biologic availability of the natural radioactive elements. Surveys of uranium mill tailings indicate little dispersal of the radioactive elements into the environment; even though untreated tailings piles would appear to be particularly vulnerable to resuspension of dust particles by wind. (U.S.)

Analysis of determination modalities concerning the exposure and emission limits values of chemical and radioactive substances; Analyse des modalites de fixation des valeurs limites d'exposition et d'emission pour les substances chimiques et radioactives

Energy Technology Data Exchange (ETDEWEB)

Schieber, C.; Schneider, T

2002-08-01

This document presents the generic approach adopted by various organizations for the determination of the public exposure limits values to chemical and radioactive substances and for the determination of limits values of chemical products emissions by some installations. (A.L.B.)

Chemical element concentrations in four lichens on a transect entering Voyageurs National Park

Science.gov (United States)

Bennett, J.; Wetmore, C.M.

1997-01-01

A three factor transect study was conducted to test the hypothesis that chemical elements from air emissions in the vicinity of International Falls, Minnesota could not be detected in lichens along a 24 km transect reaching into Voyageurs National Park. It was hypothesized that element concentrations in lichens would decline exponentially downwind and would reach background values at a distance before the park boundary. Four species (Cladina rangiferina, Evernia mesomorpha, Hypogymnia physodes, and Parmelia sulcata) were sampled at ten sites for 3 years and 17 chemical elements were measured. The most notable result was a curvilinear geographic trend for many elements, which decreased from International Falls and then increased towards the park. This trend was significant for many anthropogenic elements, including S, Hg, Cd, and Cr, and for all four species. This type of distribution pattern has been observed in Hypogymnia physodes in other studies downwind of a steel mill and an oil refinery. Cladina, a ground-dwelling lichen, generally had lower tissue concentrations of the elements than the three epiphytic species. Tissue concentrations over the 3 years of sampling declined an average of 12%. Sufficient evidence exists to conclude that lichen tissue element concentrations in the vicinity of International Falls may be related to local air emissions, and that an exponential decline of element concentrations downwind of the sources does not apply to this situation.

A rich revenue from the use of radioactive beams and radioactive targets: recent highlights from the nTOF and ISOLDE facilities (1/2)

CERN Multimedia

CERN. Geneva

2008-01-01

The On-Line Isotope Mass Separator ISOLDE is a facility dedicated to the production of a large variety of radioactive ion beams for a great number of different experiments, e.g. in the field of nuclear and atomic physics, solid-state physics, life sciences and material science. At ISOLDE, radioactive nuclides are produced in thick high-temperature targets via spallation, fission or fragmentation reactions. The targets are placed in the external proton beam of the PSB, which has an energy of 1.0 or 1.4 GeV and an intensity of about 2 microA. The target and ion-source together represent a small chemical factory for converting the nuclear reaction products into a radioactive ion beam. An electric field accelerates the ions, which are mass separated and steered to the experiments. Until now more than 600 isotopes of more than 60 elements (Z=2 to 88) have been produced with half-lives down to milliseconds and intensities up to 1011 ions per second. Through the advent of post-accelerated beams with the REX-ISOLDE c...

Radioactive elements and ionizing radiation in the environment of the alternative sites for the final disposal of nuclear waste

International Nuclear Information System (INIS)

Voutilainen, A.

1998-09-01

This report summarises a short review of the origin of earth's natural radioactivity and concentrations of radioactive elements in ground and water. The radiation doses of natural and artificial sources are examined and presented for population of both Finland and the whole world. The report includes data on the radioactivity of indoor and outdoor air, rainwater, surface and groundwater, soil and bedrock in Eurajoki, Kuhmo, Loviisa and Aeaenekoski. The radiation doses from natural sources are also estimated in each municipality separately. Natural radiation is the most significant source of radiation exposure in the world. We eat, drink and breathe radioactive elements. The most radiation dose to man comes from indoor radon. We get cosmic radiation from space and terrestrial gamma radiation from ground. Indoor radon and radon in drilled wells causes the largest variation in radiation doses between municipalities or individuals. The radiation doses in Loviisa and Aeaenekoski are bigger and in Eurajoki and Kuhmo smaller than the average in Finland. The average radiation dose from natural radiation and Chernobyl fallout is 3,5 milli-sievert per year (mSv/a) for a Finn who lives in a detached house and uses household water from waterworks. The corresponding radiation dose in Eurajoki is 3,3, in Kuhmo 2,6, in Loviisa 8,3 and in Aeaenekoski 4,2 mSv/a The average doses for persons who use household water from drilled wells are respectively 5,4 (all Finns), 4,1 (Eurajoki), 3,5 (Kuhmo), 12 (Loviisa) and 5,4 mSv/a (Aeaenekoski). The other sources of radiation, excluding indoor radon and household water, cause together less than 1 mSv per year, although these doses vary in different municipalities, too. (orig.)

PETROS - Worldwide Databank of Major Element Chemical Analyses of Igneous Rocks

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — PETROS is a worldwide data bank of major element chemical analyses of igneous rocks compiled for research and teaching purposes by Dr. Felix Mutschler and Staff at...

Evaluation of finite element codes for demonstrating the performance of radioactive material packages in hypothetical accident drop scenarios

International Nuclear Information System (INIS)

Tso, C.F.; Hueggenberg, R.

2004-01-01

Drop testing and analysis are the two methods for demonstrating the performance of packages in hypothetical drop accident scenarios. The exact purpose of the tests and the analyses, and the relative prominence of the two in the license application, may depend on the Competent Authority and will vary between countries. The Finite Element Method (FEM) is a powerful analysis tool. A reliable finite element (FE) code when used correctly and appropriately, will allow a package's behaviour to be simulated reliably. With improvements in computing power, and in sophistication and reliability of FE codes, it is likely that FEM calculations will increasingly be used as evidence of drop test performance when seeking Competent Authority approval. What is lacking at the moment, however, is a standardised method of assessing a FE code in order to determine whether it is sufficiently reliable or pessimistic. To this end, the project Evaluation of Codes for Analysing the Drop Test Performance of Radioactive Material Transport Containers, funded by the European Commission Directorate-General XVII (now Directorate-General for Energy and Transport) and jointly performed by Arup and Gesellschaft fuer Nuklear-Behaelter mbH, was carried out in 1998. The work consisted of three components: Survey of existing finite element software, with a view to finding codes that may be capable of analysing drop test performance of radioactive material packages, and to produce an inventory of them. Develop a set of benchmark problems to evaluate software used for analysing the drop test performance of packages. Evaluate the finite element codes by testing them against the benchmarks This paper presents a summary of this work

Evaluation of finite element codes for demonstrating the performance of radioactive material packages in hypothetical accident drop scenarios

Energy Technology Data Exchange (ETDEWEB)

Tso, C.F. [Arup (United Kingdom); Hueggenberg, R. [Gesellschaft fuer Nuklear-Behaelter mbH (Germany)

2004-07-01

Drop testing and analysis are the two methods for demonstrating the performance of packages in hypothetical drop accident scenarios. The exact purpose of the tests and the analyses, and the relative prominence of the two in the license application, may depend on the Competent Authority and will vary between countries. The Finite Element Method (FEM) is a powerful analysis tool. A reliable finite element (FE) code when used correctly and appropriately, will allow a package's behaviour to be simulated reliably. With improvements in computing power, and in sophistication and reliability of FE codes, it is likely that FEM calculations will increasingly be used as evidence of drop test performance when seeking Competent Authority approval. What is lacking at the moment, however, is a standardised method of assessing a FE code in order to determine whether it is sufficiently reliable or pessimistic. To this end, the project Evaluation of Codes for Analysing the Drop Test Performance of Radioactive Material Transport Containers, funded by the European Commission Directorate-General XVII (now Directorate-General for Energy and Transport) and jointly performed by Arup and Gesellschaft fuer Nuklear-Behaelter mbH, was carried out in 1998. The work consisted of three components: Survey of existing finite element software, with a view to finding codes that may be capable of analysing drop test performance of radioactive material packages, and to produce an inventory of them. Develop a set of benchmark problems to evaluate software used for analysing the drop test performance of packages. Evaluate the finite element codes by testing them against the benchmarks This paper presents a summary of this work.

Phosphated minerals to be used as radioactive reference materials

International Nuclear Information System (INIS)

Braganca, M.J.C.S.; Tauhata, L.; Clain, A.F.; Moreira, I.

2003-01-01

The production and the supplying of certified reference materials, or deliberated contaminated materials containing natural radionuclides for laboratories which analyses environmental samples are fundamentals for the correct measurements of their radioactive levels. This analysis quality represents a important step for the safeguards of the population health, and quality control of the imported and exported products, such as minerals, agricultural and raw materials. The phosphate rocks, containing significant concentrations of thorium, and used as raw material and fertilizers justified a study for better characterization and distinction to be used cas certified reference radioactive materials. Therefore, samples from the two carboanalytical-alkaline chimneys (Araxa and Catalao), and one from metasedimentar origin (Patos de Minas), distant 100 km from each other, were collected and chemical and cholecystographic characterized by optical emission, X-ray diffraction and fluorescence. The element concentrations were determined by neutron activation analysis, ICP-MS and ICP-AES. The results, after multivariate statistical analysis and study of correlations among elements, have shown geochemical similarities of the phosphates from Araxa and Catalao, and differences from Patos de Minas, despite of the geographic proximity. The concentration of thorium between 200 and 500 (mg/g) allows to use such minerals as reference materials

Radioactive particles in the environment: sources, particle characterization and analytical techniques

International Nuclear Information System (INIS)

2011-08-01

Over the years, radioactive particles have been released to the environment from nuclear weapons testing and nuclear fuel cycle operations. However, measurements of environmental radioactivity and any associated assessments are often based on the average bulk mass or surface concentration, assuming that radionuclides are homogeneously distributed as simple ionic species. It has generally not been recognised that radioactive particles present in the environment often contain a significant fraction of the bulk sample activity, leading to sample heterogeneity problems and false and/or erratic measurement data. Moreover, the inherent differences in the transport and bioavailability of particle bound radionuclides compared with those existing as molecules or ions have largely been ignored in dose assessments. To date, most studies regarding radionuclide behaviour in the soil-plant system have dealt with soluble forms of radionuclides. When radionuclides are deposited in a less mobile form, or in case of a superposition of different physico-chemical forms, the behaviour of radionuclides becomes much more complicated and extra efforts are required to provide information about environmental status and behaviour of radioactive particles. There are currently no documents or international guides covering this aspect of environmental impact assessments. To fill this gap, between 2001 and 2008 the IAEA performed a Coordinated Research Programme (CRP- G4.10.03) on the 'Radiochemical, Chemical and Physical Characterization of Radioactive Particles in the Environment' with the objective of development, adoption and application of standardized analytical techniques for the comprehensive study of radioactive particles. The CRP was in line with the IAEA project intended to assist the Member States in building capacity for improving environmental assessments and for management of sites contaminated with radioactive particles. This IAEA-TECDOC presents the findings and achievements of

A model for determination of screening level for radioactive elements in soil

International Nuclear Information System (INIS)

Peres, Ana Claudia

2007-01-01

At the present, decision about clean-up of Brazilian sites contaminated with radioactive isotopes is addressed on a case-by-case basis, since there is no general guidance or recommendation to support actions in early phases of the problem identification. For chemicals, CETESB - the governmental organization responsible for preventing and controlling environmental pollution in Sao Paulo State - established background values, prevention and intervention, as the first step to implement a remediation actions based on human health risk assessment. The aim of this study was to develop a methodology for the establishment of target values for radioactive soil contamination, as far as possible consistent and compatible with the approach adopted by CETESB for sites contaminated with chemicals. The following steps have been addressed in this study: conceptual scenario and model development; codification of the equations in an electronic spreadsheet; selection of proper range and statistical distribution of the input values; derivation of the intervention levels for selected radionuclides using Monte Carlo methods. The mathematical model developed was mainly based on the equations used by the U.S. Environmental Protection Agency (EPA) and by the National Council on Radiation Protection and Measurements (NCRP) for soil screening purposes. Intervention and prevention values are presented for adult and 10 years old child, for each 3 exposure scenarios: agricultural, residential and industrial; the following radionuclides were considered: 3 H, 14 C, 32 P, 35 S, 45 Ca, 51 Cr, 90 Sr, 125 I, 131 I, 134 Cs, 137 Cs, 210 Pb, 226 Ra, 228 Ra, 232 Th, 238 U, 239 Pu and 241 Am. Quality reference values were determined for 40 K, 137 Cs, 210 Pb, 226 Ra, 228 Ra, 228 Th, Th-nat e U-nat. Results obtained in this study showed a good agreement with those reported by NCRP, considering that the equations and the input data used in both models are not the same ones.(author)

Halftone display, particularly for a high resolution radioactivity distribution detection system

International Nuclear Information System (INIS)

Grenier, R.P.

1977-01-01

A device is described for presenting a halftone pictorial presentation composed of dot picture elements by selectively controlling the number of dot picture elements per unit area at locations on a display. In a high resolution radioactivity distribution detection system, the number of detected radioactive elements at XY locations of an array of sensing devices are fed to a computer and stored at corresponding address locations. The number of radioactive events detected at each address location is normalized into Gray scale coded signals as a function of the greatest number of radioactive events detected at any one address location. The normalized Gray scale coded signals are applied to a display for controlling the number of dot picture elements per unit area presented at corresponding XY locations on the display. The number of radioactive events detected at XY locations of the array are presented on the display as a halftone pictorial representation; the greatest number of picture dot elements per unit are being presented as a brighter image

Stellar alchemy: The origin of the chemical elements

International Nuclear Information System (INIS)

Norman, E.B.

1994-01-01

What makes the stars shine? This question puzzled human beings for thousands of years. Early in this century, chemists and physicists discovered radioactivity; and the nuclear model of the atom was developed. Once nuclear reactions were produced in the laboratory, it did not take long before their role in stellar energy generation was realized. The theory that nuclear fusion is the source of stellar energy was initially developed in the 1930's and was elaborated in detail in the 1950's. Only within the last ten years, however, have astronomical observations provided direct confirmation of these theoretical ideas. In this paper, I describe the sequences of nuclear reactions that are believed to be responsible for the power generation in stars. The ashes of these reactions are the heavy elements that we find on earth and throughout the universe. The evolution and final fates of stars are examined. The key astronomical observations that provide support for these theoretical ideas are presented

The uses of synchrotron radiation sources for elemental and chemical microanalysis

Science.gov (United States)

Chen, J.R.; Chao, E.C.T.; Minkin, J.A.; Back, J.M.; Jones, K.W.; Rivers, M.L.; Sutton, S.R.

1990-01-01

Synchrotron radiation sources offer important features for the analysis of a material. Among these features is the ability to determine both the elemental composition of the material and the chemical state of its elements. For microscopic analysis synchrotron X-ray fluorescence (SXRF) microprobes now offer spatial resolutions of 10 ??m with minimum detection limits in the 1-10 ppm range depending on the nature of the sample and the synchrotron source used. This paper describes the properties of synchrotron radiation and their importance for elemental analysis, existing synchrotron facilities and those under construction that are optimum for SXRF microanalysis, and a number of applications including the high energy excitation of the K lines of heavy elements, microtomography, and XANES and EXAFS spectroscopies. ?? 1990.

Studies on the radioactivity in certain pelagic fish. III. Separation and confirmation of /sup 65/Zn in the muscle tissue of a skipjack

Energy Technology Data Exchange (ETDEWEB)

Yamada, K; Tozawa, H; Amano, K; Takase, A

1955-01-01

Ashed sample of the muscle tissue of skipjack, which were caught by Shunkotsu-Maru on June 19th near Bikini Atoll was used for the present study. Ion exchanger method, using Dowex 50, was applied to separate radioactive elements with 0.2 HC1, 0.5% oxalic acid and 5% annonium citrate (pH 3.53, 4.18, 4.60, 5.02, 5.63 and 6.42) as the eluents. Elution curve of the ashed muscle is shown in Figure 1. Appreciable amounts of cationic radioactive elements were separated by 0.5% oxalic and by 5% annonium citrate at the pH of 4.18 and also anionic radioactive elements were obtained by 0.2N HC1. As the fraction, which can be withdrawn by annonium citrate as pH 4.18, was proved the most active; further analysis was undertaken according to the scheme cited in Figures 2 and 5. In addition to these chemical separation, absorption curve of this specimen with tin foil was examined simultaneously (Figure 3) and thus the radioactive /sup 65/Zn was confirmed to be present in the fish muscle. Although it was difficult to detect radioactivity in rare-earth and alkaline-earth groups in the muscle tissue, attempts are being made for more precise examination.

Chemical and nuclear properties of Rutherfordium (Element 104)

International Nuclear Information System (INIS)

Kacher, C.D.

1995-01-01

The chemical-properties of rutherfordium (Rf) and its group 4 homologs were studied by sorption on glass support surfaces coated with cobalt(II)ferrocyanide and by solvent extraction with tributylphosphate (TBP) and triisooctylamine (TIOA). The surface studies showed that the hydrolysis trend in the group 4 elements and the pseudogroup 4 element, lb, decreases in the order Rf>Zr∼Hf>Th. This trend was attributed to relativistic effects which predicted that Rf would be more prone to having a coordination number of 6 than 8 in most aqueous solutions due to a destabilization of the 6d 5/2 shell and a stabilization of the 7p l/2 shell. This hydrolysis trend was confirmed in the TBP/HBr solvent extraction studies which showed that the extraction trend decreased in the order Zr>Hf>Rf?Ti for HBr, showing that Rf and Ti did not extract as well because they hydrolyzed more easily than Zr and Hf. The TIOA/HF solvent extraction studies showed that the extraction trend for the group 4 elements decreased in the order Ti>Zr∼Hf>Rf, in inverse order from the trend of ionic radii Rf>Zr∼Hf>Ti. An attempt was made to produce 263 Rf (a) via the 248 Cm( 22 Ne, α3n) reaction employing thenoyltrifluoroacetone (TTA) solvent extraction chemistry and (b) via the 249 Bk( 18 O,4n) reaction employing the Automated Rapid Chemistry Apparatus (ARCA). In the TTA studies, 16 fissions were observed but were all attributed to 256 Fm. No alpha events were observed in the Rf chemical fraction. A 0.2 nb upper limit production cross section for the 248 Cm( 22 Ne, α3n) 263 Rf reaction was calculated assuming the 500-sec half-life reported previously by Czerwinski et al. [CZE92A

Finite element code FENIA verification and application for 3D modelling of thermal state of radioactive waste deep geological repository

Science.gov (United States)

Butov, R. A.; Drobyshevsky, N. I.; Moiseenko, E. V.; Tokarev, U. N.

2017-11-01

The verification of the FENIA finite element code on some problems and an example of its application are presented in the paper. The code is being developing for 3D modelling of thermal, mechanical and hydrodynamical (THM) problems related to the functioning of deep geological repositories. Verification of the code for two analytical problems has been performed. The first one is point heat source with exponential heat decrease, the second one - linear heat source with similar behavior. Analytical solutions have been obtained by the authors. The problems have been chosen because they reflect the processes influencing the thermal state of deep geological repository of radioactive waste. Verification was performed for several meshes with different resolution. Good convergence between analytical and numerical solutions was achieved. The application of the FENIA code is illustrated by 3D modelling of thermal state of a prototypic deep geological repository of radioactive waste. The repository is designed for disposal of radioactive waste in a rock at depth of several hundred meters with no intention of later retrieval. Vitrified radioactive waste is placed in the containers, which are placed in vertical boreholes. The residual decay heat of radioactive waste leads to containers, engineered safety barriers and host rock heating. Maximum temperatures and corresponding times of their establishment have been determined.

A model for evaluating the radioactive contamination in the urban environment

International Nuclear Information System (INIS)

Hwang, Won Tae; Kim, Eun Han; Jeong, Hyo Joon; Suh, Kyung Suk; Han, Moon Hee

2005-01-01

A model for evaluating radioactive contamination in the urban environment, named METRO-K, was developed as a basic step for accident consequence analysis in case of an accidental release. The three kind of radionuclides ( 137 Cs, 106 Ru, 131 I) and the different chemical forms of iodine (particulate, organic and elemental forms) are considered in the model. The radioactive concentrations are evaluated for the five types of surface (roof, paved road, wall, lawn/soil, tree) as a function of time. Using the model, the contaminative impacts of the surfaces were intensively investigated with respect to with and without precipitation during the measurement periods of radionuclides in air. In addition, a practical application study was conducted using 137 Cs concentration in air and precipitation measured in an European country at the Chernobyl accident. As a result, precipitation was an influential factor in surface contamination. The degree of contamination was strongly dependent on the types of radionuclide and surface. Precipitation was more influential in contamination of 137 Cs than that of 131 I (elemental form)

Sources of radioactive contamination inside houses

International Nuclear Information System (INIS)

Sajet, A.S.

2010-01-01

People may be exposed at home to multiple sources of nuclear radiation such as gamma, beta and alpha rays emitters. House atmosphere is polluted with nuclear radiation from water pollutants and rocks used in the construction. Radon is the only radioactive non-metallic element. Environmental organizations estimated that all houses contain varying concentrations of radon gas, and the residents are exposed to levels of radon over the years. The source of radon in houses is uranium, which may be found in rocks of the house, soil of the garden, water of the deep artesian wells and building materials, especially granite rocks. Breathing air that contains high levels of radon causes lung cancer. Radon is the second cause of lung disease after smoking. There are many means to reduce house pollution including: utilisation of air filters to remove contaminated dust particles, keep residential areas away from the establishments that use nuclear technology or embedded by nuclear waste, avoid using materials made from asbestos in construction works and proper use and disposal of chemicals and medicines containing radioactive isotopes. (author)

Radioactive waste disposal

International Nuclear Information System (INIS)

Bohm, H.; Closs, K.D.; Kuhn, K.

1981-01-01

The solutions to the technical problem of the disposal of radioactive waste are limited by a) the state of knowledge of reprocessing possibilites, b) public acceptance of the use of those techniques which are known, c) legislative procedures linking licensing of new nuclear power plants to the solution of waste problems, and d) other political constraints. Wastes are generated in the mining and enriching of radioactive elements, and in the operation of nuclear power plants as well as in all fields where radioactive substances may be used. Waste management will depend on the stability and concentration of radioactive materials which must be stored, and a resolution of the tension between numerous small storage sites and a few large ones, which again face problems of public acceptability

A laboratory activity for teaching natural radioactivity

Science.gov (United States)

Pilakouta, M.; Savidou, A.; Vasileiadou, S.

2017-01-01

This paper presents an educational approach for teaching natural radioactivity using commercial granite samples. A laboratory activity focusing on the topic of natural radioactivity is designed to develop the knowledge and understanding of undergraduate university students on the topic of radioactivity, to appreciate the importance of environmental radioactivity and familiarize them with the basic technology used in radioactivity measurements. The laboratory activity is divided into three parts: (i) measurements of the count rate with a Geiger-Muller counter of some granite samples and the ambient background radiation rate, (ii) measurement of one of the samples using gamma ray spectrometry with a NaI detector and identification of the radioactive elements of the sample, (iii) using already recorded 24 h gamma ray spectra of the samples from the first part (from the Granite Gamma-Ray Spectrum Library (GGRSL) of our laboratory) and analyzing selected peaks in the spectrum, students estimate the contribution of each radioactive element to the total specific activity of each sample. A brief description of the activity as well as some results and their interpretation are presented.

A chemical basis for the partitioning of radionuclides in incinerator operation

International Nuclear Information System (INIS)

Burger, L.L.

1995-01-01

Incineration as a method of treating radioactive or mixed waste is attractive because of volume reduction, but may result in high concentrations of some hazardous components. For safety reasons during operation, and because of the environmental impact of the plant, it is important to know how these materials partition between the furnace slay, the fly ash, and the stack emission. The chemistry of about 50 elements is discussed and through consideration of high temperature thermodynamic equilibria, an attempt is made to provide a basis for predicting how various radionuclides and heavy metals behave in a typical incinerator. The chemistry of the individual elements is first considered and a prediction of the most stable chemical species in the typical incinerator atmosphere is made. The treatment emphasizes volatility and the parameters considered are temperature, acidity, oxygen, sulfur, and halogen content, and the presence of several other key non-radioactive elements. A computer model is used to calculate equilibrium concentrations of many species in several systems at temperatures ranging from 500 to 1600 degrees K. It is suggested that deliberate addition of various feed chemicals can have a major impact on the fate of many radionuclides and heavy metals. Several problems concerning limitations and application of the data are considered

Basic chemistry for radioactive waste management

International Nuclear Information System (INIS)

Eom, Tae Yoon; Kim, Sung Soo; Kim, Jeong Seok; Park, Soon Dal; Park, Yong Jun; Seo, Moo Yeul; Sohn, Se Chul; Song, Byung Chul; Lee, Chang Heun; Jun, Young Shin

1992-03-01

Chemical analysis on geological materials was performed for radioactive waste management. Seven major elements including Mn, Fe in JG-2, DWC-l, W-2 and BIR standard samples were determined by acid digestion decomposition and fusion method with sodium carbonate, respectively. About 40 trace elements including Na were determined by instrumental neutron activation analysis method. Retention times of lanthanides were measured by ion chromatography using α-hydroxyisobutyric acid and mandelic acid, respectively. This result gave good agreement between the measured value and the calculated by stepwise elution equation. Trace amount of gallium and indium in natural water were analysed by adsorptive stripping voltammetry using Morin as chelating agent. Detection limit of gallium and indium were 1.1 nM nd 2.6 nM in each. Low level of H-3 and C-14 in natural water were measured by liquid scintillation counting technique. Minimum detectable activity(MDA) by this method were shown to be 0.722 Bq/L and 0.111 Bq/L. (Author)

Soil-to-plant transfer of elements is not linear: Results for five elements relevant to radioactive waste in five boreal forest species

Energy Technology Data Exchange (ETDEWEB)

Tuovinen, Tiina S.; Roivainen, Paeivi, E-mail: paivi.roivainen@uef.fi; Makkonen, Sari; Kolehmainen, Mikko; Holopainen, Toini; Juutilainen, Jukka

2011-12-01

Element-specific concentration ratios (CRs) assuming that plant uptake of elements is linear are commonly used in radioecological modelling to describe the soil-to-plant transfer of elements. The goal of this study was to investigate the validity of the linearity assumption in boreal forest plants, for which only limited relevant data are available. The soil-to-plant transfer of three essential (Mo, Ni, Zn) and two non-essential (Pb, U) elements relevant to the safety of radioactive waste disposal was studied. Three understory species (blueberry, narrow buckler fern and May lily) and two tree species (Norway spruce and rowan) were included. Examining CRs as a function of soil concentration showed that CR was not constant but decreased with increasing soil concentrations for all elements and plant species. A non-linear equation fitted fairly well with the empirical data; the R{sup 2}-values for this equation were constantly higher than those for the linear fit. The difference between the two fits was most evident at low soil concentrations where the use of constant CRs underestimated transfer from soil to plants. Site-specific factors affected the transfer of Mo and Ni. The results suggested that systematic variation with soil concentrations explains a part of the large variation of empirically determined CRs, and the accuracy of modelling the soil-to-plant transfer might be improved by using non-linear methods. Non-linearity of soil-to-plant transfer has been previously reported for a few different species, elements and environments. The present study systematically tested the linearity assumption for five elements (both essential and non-essential) and in five boreal forest species representing different growth traits and phylogenies. The data supported non-linearity in all cases.

Soil-to-plant transfer of elements is not linear: Results for five elements relevant to radioactive waste in five boreal forest species

International Nuclear Information System (INIS)

Tuovinen, Tiina S.; Roivainen, Päivi; Makkonen, Sari; Kolehmainen, Mikko; Holopainen, Toini; Juutilainen, Jukka

2011-01-01

Element-specific concentration ratios (CRs) assuming that plant uptake of elements is linear are commonly used in radioecological modelling to describe the soil-to-plant transfer of elements. The goal of this study was to investigate the validity of the linearity assumption in boreal forest plants, for which only limited relevant data are available. The soil-to-plant transfer of three essential (Mo, Ni, Zn) and two non-essential (Pb, U) elements relevant to the safety of radioactive waste disposal was studied. Three understory species (blueberry, narrow buckler fern and May lily) and two tree species (Norway spruce and rowan) were included. Examining CRs as a function of soil concentration showed that CR was not constant but decreased with increasing soil concentrations for all elements and plant species. A non-linear equation fitted fairly well with the empirical data; the R 2 -values for this equation were constantly higher than those for the linear fit. The difference between the two fits was most evident at low soil concentrations where the use of constant CRs underestimated transfer from soil to plants. Site-specific factors affected the transfer of Mo and Ni. The results suggested that systematic variation with soil concentrations explains a part of the large variation of empirically determined CRs, and the accuracy of modelling the soil-to-plant transfer might be improved by using non-linear methods. Non-linearity of soil-to-plant transfer has been previously reported for a few different species, elements and environments. The present study systematically tested the linearity assumption for five elements (both essential and non-essential) and in five boreal forest species representing different growth traits and phylogenies. The data supported non-linearity in all cases.

Geochemistry and mineralogy of the radioactive minerals associated with some pegmatite veins of the Ukma-Nawahatu Hursi sector, Purulia district, W.B., in the Precambrian Chhotanagpur Gneissic complex

International Nuclear Information System (INIS)

Baidya, Tapan Kumar

2014-01-01

Some barite-bearing pegmatites in the Ukma-Nawahatu-Hursi sector (23° 25 min - 26 sec N, 86° 02 min - 04 sec E) in Purulia dist., West Bengal, have association of radioactive minerals in the form of coarse-grained pitchblack lumps and irregular patches. The present author and his associates first reported the occurrence of this radioactive belt along a ENE-WSW shearzone during their fieldwork in November, 1978. Groundborne radiometric survey and isorad mapping has established a radioactive high zone of about 15 km length running through Ukma, Nawahatu and Hursi areas. Mineralogical studies of the radioactive minerals have revealed the occurrence of Chevkinite, Aeschynite, Brannerite, Allanite, Uraninite, Tyuyamunite, Davidite, Euxenite, Samarskite, Thorutite, Autunite, Cerianite, in association with quartz, barite, microcline as the principal minerals and various minor minerals like biotite, vermiculite, hornblende, augite, orthoclase, celsian, muscovite, calcite, epidote, zoisite, ilmenite, sphene, rutile, hematite, magnetite, anatase, galena and sodic plagioclase. The barite-bearing pegmatites occur as lenses or lenticular veins hosted by garnetiferous sillimanite-biotite-quartz-schist or occasionally by migmatite. Near Nawahatu the radioactive barite-pegmatite vein occurs at or near the junction between the footwall amphibolite and hangingwall garnetiferous schist. The pegmatite veins have followed mainly schistosity of the host rock and dip at 70°-80° towards south. Chemical analyses of individual radioactive minerals by SEM-EDX and also of the bulk radioactive lumps by ICP-MS have shown significant concentration of U, Tb and Rare earths. Minor and trace element analyses also record notable contents of Zr, Ga, Sc, Pb, Zn, Nb, Cu, Ni, V, Cr, As, W, Pd, Ag and TI. Details of chemical analytical data are presented here. Chemically active fluids generated during metamorphism, metasomatism and granitic activity appear to have played a significant role in the

Method and techniques of radioactive waste treatment

International Nuclear Information System (INIS)

Ghafar, M.; Aasi, N.

2002-04-01

This study illustrates the characterization of radioactive wastes produced by the application of radioisotopes in industry and research. The treatment methods of such radioactive wastes, chemical co-precipitation and ion exchange depending on the technical state of radioactive waste management facility in Syria were described. The disposal of conditioned radioactive wastes, in a safe way, has been discussed including the disposal of the radioactive sources. The characterizations of the repository to stock conditioned radioactive wastes were mentioned. (author)

A historical approach to teaching the concept of the chemical element

OpenAIRE

Cachapuz, António; Paixão, Fátima

2005-01-01

A novel teaching strategy is described, which was developed to introduce the key notion of chemical elements to 15-year-old Portuguese chemistry pupils. The strategy started from the analysis of the so-called ‘Lavoisier law ’and explored the relationships between macro and micro level chemistry in an innovative way. The key idea was first to explore the macro level (mass conservation) to help pupils consider the existence of indestructible units (elements, micro level) as a logical necessity ...

New facility for processing and storage of radioactive and toxic chemical waste

International Nuclear Information System (INIS)

Gallagher, F.E. III

1976-01-01

A new facility for the processing and storage of radioactive and toxic chemical waste is described. The facility is located in the science and engineering complex of the Santa Barbara campus of the University of California, near the Pacific Ocean. It is designed to provide a safe and secure processing and storage area for hazardous wastes, while meeting the high aesthetic standards and ecological requirements of campus and community regulatory boards. The ventilation system and fire prevention features will be described in detail. During the design phase, a small laboratory was added to provide an area for the radiation protection and industrial hygiene programs. Operational experience with this new facility is discussed

The uses of synchrotron radiation sources for elemental and chemical microanalysis

International Nuclear Information System (INIS)

Chen, J.R.; Chao, E.C.T.; Minkin, J.A.; Back, J.M.; Jones, K.W.; Rivers, M.L.; Sutton, S.R.

1989-08-01

Synchrotron radiation sources offer important features for the analysis of a material. Among these features is the ability to determine both the elemental composition of the material and the chemical state of its elements. For microscopic analysis synchrotron x-ray fluorescence (SXRF) microprobes now offer spatial resolutions of 10μm with minimum detection limits in the 1--10 ppM range depending on the nature of the sample and the synchrotron source used. This paper describes the properties of synchrotron radiation and their importance for elemental analysis, existing synchrotron facilities and those under construction that are optimum for SXRF microanalysis, and a number of applications including the high energy excitation of the K lines of heavy elements, microtomography, and XANES and EXAFS spectroscopies. 45 refs., 8 figs., 1 tab

Method for purification of environmental objects, contaminated with radioactive substancesas a result of natural disasters

International Nuclear Information System (INIS)

Mammadov, Kh.; Shiraliyeva, Kh.; Mirzayev, N.; Garibov, R.; Allahverdiyev, G.; Aliyeva, U.; Farajova, A.

2017-01-01

, centrifugation and evaporation/ and vegetation /firing, treatment with nitric acid and distilled water/ taken from all regions of the republic were carried out. Mineral compositions have been studied by X-ray fluorescence, γ, α, β spectroscopy, electron microscopy and chemical methods. Four times washing /stirring and extraction/ by distilled water were used to clean the soil samples. It is possible to re-wash the soil for achieve complete cleaning of deeply contaminated soils. Methods sedimentation, centrifugation, mass spectroscopy and adsorption on activated carbon or on organic porous adsorbents /copolymers of maleic anhydride with styrene hardened by polyethylene polyamines/ were used for purification (separation of heavy elements, radioactive isotopes) of water samples and water extracts of soil.

Chemical elements in invertebrate orders for environmental quality studies

Energy Technology Data Exchange (ETDEWEB)

Magalhaes, Marcelo R.L.; Franca, Elvis J.; Paiva, Jose D.S.; Hazin, Clovis A., E-mail: marcelo_rlm@hotmail.com, E-mail: ejfranca@cnen.gov.br, E-mail: dan-paiva@hotmail.com, E-mail: chazin@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Fonseca, Felipe Y.; Fernandes, Elisabete A. de Nadai; Bacchi, Marcio A., E-mail: felipe-yamada@hotmail.com, E-mail: lis@cena.usp.br, E-mail: mabacchi@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

2013-07-01

Among the biomonitors of environmental quality, there is a lack of studies on using invertebrates to evaluate quantitatively chemical elements in ecosystems. This group of animals is quite numerous, widely distributed and adaptable to the most diverse environmental conditions. These features are very useful for the environmental quality assessment, as well as the several occurring insect-plant interactions performing essential functions in ecosystems. The objective of this work is to study the variability of chemical composition of invertebrate orders for using in environmental quality monitoring studies. Instrumental neutron activation analysis - INAA was applied to determine some nutrients and trace elements in invertebrate samples. Sampling by pitfall traps was carried out in riverine ecosystems from the urban area from the Piracicaba Municipality, State of Sao Paulo, Brazil. Invertebrate and reference material samples were irradiated in the nuclear research reactor IEA-R1, Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN. Fragments of a Ni-Cr alloy were irradiated for monitoring the thermal neutron flux. Hymenoptera order was considered the most representative according to the total number of sampled species (about 60%). Significant amounts of Ba, Br, Fe and Sc were found in invertebrates of the order Opiliones. Potassium, rubidium and zinc were highly accumulated in species from Blattodea order, indicating a consistent pattern of accumulation for this invertebrate order. Taking into account the abundance of Hymenoptera order, the chemical composition of its species was significant different at the 95% confidence level for Br and Na in the sampled locals. (author)

Chemical elements in invertebrate orders for environmental quality studies

International Nuclear Information System (INIS)

Magalhaes, Marcelo R.L.; Franca, Elvis J.; Paiva, Jose D.S.; Hazin, Clovis A.; Fonseca, Felipe Y.; Fernandes, Elisabete A. de Nadai; Bacchi, Marcio A.

2013-01-01

Among the biomonitors of environmental quality, there is a lack of studies on using invertebrates to evaluate quantitatively chemical elements in ecosystems. This group of animals is quite numerous, widely distributed and adaptable to the most diverse environmental conditions. These features are very useful for the environmental quality assessment, as well as the several occurring insect-plant interactions performing essential functions in ecosystems. The objective of this work is to study the variability of chemical composition of invertebrate orders for using in environmental quality monitoring studies. Instrumental neutron activation analysis - INAA was applied to determine some nutrients and trace elements in invertebrate samples. Sampling by pitfall traps was carried out in riverine ecosystems from the urban area from the Piracicaba Municipality, State of Sao Paulo, Brazil. Invertebrate and reference material samples were irradiated in the nuclear research reactor IEA-R1, Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN. Fragments of a Ni-Cr alloy were irradiated for monitoring the thermal neutron flux. Hymenoptera order was considered the most representative according to the total number of sampled species (about 60%). Significant amounts of Ba, Br, Fe and Sc were found in invertebrates of the order Opiliones. Potassium, rubidium and zinc were highly accumulated in species from Blattodea order, indicating a consistent pattern of accumulation for this invertebrate order. Taking into account the abundance of Hymenoptera order, the chemical composition of its species was significant different at the 95% confidence level for Br and Na in the sampled locals. (author)

Radioactivity and deep geothermal energy; Radioaktivitaet und tiefe Geothermie

Energy Technology Data Exchange (ETDEWEB)

Janczik, Sebastian; Kaltschmitt, Martin [Technische Univ. Hamburg-Harburg (Germany). Inst. fuer Umwelttechnik und Energiewirtschaft; Merkel, Broder [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Geologie

2012-02-15

Due to recent developments in energy politics renewable energies get more and more importance in Germany. This is especially true for geothermal energy representing a promising option for the environmentally sound and secure generation of heat and electricity. But there are a lot of very emotional discussions due to radioactive residues and wastes produced by a geothermal plant. Thus this paper compares radioactivity resulting from geothermal energy with radioactivity coming from other natural sources. In doing so it becomes obvious that naturally radioactive sources exist in all parts of the ecosphere (i.e. air, water, soil). The paper shows also that the specific activities of radioactive elements from geothermal energy in form of residues and waste emerge from radioactive decay of nuclides and that their radiation is not higher than the radiation of other naturally occurring radioactive elements. (orig.)

INAA application in the assessment of chemical element mass fractions in adult and geriatric prostate glands

International Nuclear Information System (INIS)

Zaichick, Vladimir; Zaichick, Sofia

2014-01-01

The variation with age of the mass fraction of 37 chemical elements in intact nonhyperplastic prostate of 65 healthy 21–87 year old males was investigated by instrumental neutron activation analysis with high resolution spectrometry of short- and long-lived radionuclides. Mean values (M±SΕΜ) for mass fractions (mg kg −1 , dry mass basis) of the chemical elements studied were: Ag—0.055±0.007, Br—33.2±3.3, Ca—2150±118, Cl—13014±703, Co—0.038±0.003, Cr—0.47±0.05, Fe—99.3±6.1, Hg—0.044±0.006, K—11896±356, Mg—1149±68, Mn—1.41±0.07, Na—10886±339, Rb—12.3±0.6, Sb—0.049±0.005, Sc—0.021±0.003, Se—0.65±0.03, and Zn—795±71. The mass fraction of other chemical elements measured in this study were lower than the corresponding detection limits (mg kg −1 , dry mass basis): As<0.1, Au<0.01, Ba<100, Cd<2, Ce<0.1, Cs<0.05, Eu<0.001, Gd<0.02, Hf<0.2, La<0.5, Lu<0.003, Nd<0.1, Sm<0.01, Sr<3, Ta<0.01, Tb<0.03, Th<0.05, U<0.07, Yb<0.03, and Zr<0.3. This work revealed that there is a significant trend for increase with age in mass fractions of Co (p<0.0085), Fe (p<0.037), Hg (p<0.035), Sc (p<0.015), and Zn (p<0.0014) and for a decrease in the mass fraction of Mn (p<0.018) in prostates, obtained from young adult up to about 60 years, with age. In the nonhyperplastic prostates of males in the sixth to ninth decades, the magnitude of mass fractions of all chemical element were maintained at near constant levels. Our finding of correlation between the prostatic chemical element mass fractions indicates that there is a great variation of chemical element relationships with age. - Highlights: • 37 trace elements were determined in prostate of 65 healthy 21–87 year old males by NAA. • Co, Fe, Hg, Sc, and Zn contents significantly increase with age. • Mn content significantly decreases with age. • All elemental contents in the sixth to ninth decades are near constant level. • There is a great disturbance of chemical element

Studies on the separation and purification of strontium from the highly radioactive waste flow of fuel element reprocessing

International Nuclear Information System (INIS)

Tuerker, A.

1989-10-01

The quantity of spent fuel elements is increasing due to the extended peaceful uses of nuclear energy. Of the numerous fission products, strontium has an interesting application potential as a radiation or energy source for utilization in various industrial fields. A necessary condition for its use is its isolation in high radiochemical purity from the highly radioactive waste flow of the Purex process. In the present study, precipitation and coprecipitation reactions, and in particular ion exchange reactions, were chosen from among the various possible chemical and physical separation methods and examined with respect to their suitability for a selective separation of strontium from the other fission products. In selecting separation materials, particularly with respect to radiation resistance, thermal stability and selectivity, polyantimonic acid proved to be the best absorbent (even in a very acid medium) for strontium. Furthermore, the behaviour of the most important radionuclides was studied with respect to the denitration reaction from a 5 molar nitric acid solution. On the basis of the high demands made on the purity of the product, a method was developed by combining lead sulphate carrier precipitation with an ion exchange reaction on polyantimonic acid and is shown in a flow chart. (orig.) [de

Characteristics of soil-to-plant transfer of elements relevant to radioactive waste in boreal forest

Energy Technology Data Exchange (ETDEWEB)

Roivainen, P.

2011-07-01

The use of nuclear energy generates large amounts of different types of radioactive wastes that can be accidentally released into the environment. Soil-to-plant transfer is a key process for the dispersion of radionuclides in the biosphere and is usually described by a concentration ratio (CR) between plant and soil concentrations in radioecological models. Our knowledge of the soil-to-plant transfer of many radionuclides is currently limited and concerns mainly agricultural species and temperate environments. The validity of radioecological modelling is affected by the accuracy of the assumptions and parameters used to describe soil-to-plant transfer. This study investigated the soil-to-plant transfer of six elements (cobalt (Co), molybdenum (Mo), nickel (Ni), lead (Pb), uranium (U) and zinc (Zn)) relevant to radioactive waste at two boreal forest sites and assessed the factors affecting the CR values. May lily (Maianthemum bifolium), narrow buckler fern (Dryopteris carthusiana) and blueberry (Vaccinium myrtillus) were selected as representatives of understory species, while rowan (Sorbus aucuparia) and Norway spruce (Picea abies) represented trees in this study. All the elements studied were found to accumulate in plant roots, indicating that separate CR values for root and aboveground plant parts are needed. The between-species variation in CR values was not clearly higher than the within-species variation, suggesting that the use of generic CR values for understory species and trees is justified. No linear relationship was found between soil and plant concentrations for the elements studied and a non-linear equation was found to be the best for describing the dependence of CR values on soil concentration. Thus, the commonly used assumption of a linear relationship between plant and soil concentrations may lead to underestimation of plant root uptake at low soil concentrations. Plant nutrients potassium, magnesium, manganese, phosphorus and sulphur were found to

Characteristics of soil-to-plant transfer of elements relevant to radioactive waste in boreal forest

International Nuclear Information System (INIS)

Roivainen, P.

2011-01-01

The use of nuclear energy generates large amounts of different types of radioactive wastes that can be accidentally released into the environment. Soil-to-plant transfer is a key process for the dispersion of radionuclides in the biosphere and is usually described by a concentration ratio (CR) between plant and soil concentrations in radioecological models. Our knowledge of the soil-to-plant transfer of many radionuclides is currently limited and concerns mainly agricultural species and temperate environments. The validity of radioecological modelling is affected by the accuracy of the assumptions and parameters used to describe soil-to-plant transfer. This study investigated the soil-to-plant transfer of six elements (cobalt (Co), molybdenum (Mo), nickel (Ni), lead (Pb), uranium (U) and zinc (Zn)) relevant to radioactive waste at two boreal forest sites and assessed the factors affecting the CR values. May lily (Maianthemum bifolium), narrow buckler fern (Dryopteris carthusiana) and blueberry (Vaccinium myrtillus) were selected as representatives of understory species, while rowan (Sorbus aucuparia) and Norway spruce (Picea abies) represented trees in this study. All the elements studied were found to accumulate in plant roots, indicating that separate CR values for root and aboveground plant parts are needed. The between-species variation in CR values was not clearly higher than the within-species variation, suggesting that the use of generic CR values for understory species and trees is justified. No linear relationship was found between soil and plant concentrations for the elements studied and a non-linear equation was found to be the best for describing the dependence of CR values on soil concentration. Thus, the commonly used assumption of a linear relationship between plant and soil concentrations may lead to underestimation of plant root uptake at low soil concentrations. Plant nutrients potassium, magnesium, manganese, phosphorus and sulphur were found to

Combustible radioactive waste treatment by incineration and chemical digestion

International Nuclear Information System (INIS)

Stretz, L.A.; Crippen, M.D.; Allen, C.R.

1980-01-01

A review is given of present and planned combustible radioactive waste treatment systems in the US. Advantages and disadvantages of various systems are considered. Design waste streams are discussed in relation to waste composition, radioactive contaminants by amount and type, and special operating problems caused by the waste

Chemical Gel for Surface Decontamination

International Nuclear Information System (INIS)

Jung, Chong Hun; Moon, J. K.; Won, H. J.; Lee, K. W.; Kim, C. K.

2010-01-01

Many chemical decontamination processes operate by immersing components in aggressive chemical solutions. In these applications chemical decontamination technique produce large amounts of radioactive liquid waste. Therefore it is necessary to develop processes using chemical gels instead of chemical solutions, to avoid the well-known disadvantages of chemical decontamination techniques while retaining their high efficiency. Chemical gels decontamination process consists of applying the gel by spraying it onto the surface of large area components (floors, walls, etc) to be decontaminated. The gel adheres to any vertical or complex surface due to their thixotropic properties and operates by dissolving the radioactive deposit, along with a thin layer of the gel support, so that the radioactivity trapped at the surface can be removed. Important aspects of the gels are that small quantities can be used and they show thixitropic properties : liquid during spraying, and solid when stationary, allowing for strong adherence to surfaces. This work investigates the decontamination behaviors of organic-based chemical gel for SS 304 metallic surfaces contaminated with radioactive materials

Evaluation of air pollution due to natural radioactive elements

International Nuclear Information System (INIS)

Perez, B. A.; Lopez, M. E.

2014-08-01

The presence of radioactive materials in the crustal and as consequence present in the surface, originate the natural radioactive contamination in the different solid, liquid and gaseous materials; particularly in the air that we breathe. Among these radioactive materials that contribute to the environmental pollution are the presences of uranium, radio, thorium and their respective disintegration chains, as the gas radon (Rn-222) that spreads in the air; whose presence increases in areas where the seismic activity is notorious or other natural events take place, case of the Lima (Peru) City. In this work we show the measurements realized during two consecutive years in the roof of a building of three floors in the Lima City, with the purpose of establishing the fluctuations of this gassy pollutant in the surrounding air. The measurements were made using nitrocellulose detectors (Lr-115 type 2) applying the nuclear prints technique. The obtained results allowing to have an indicator of the Rn-222 presence in the air during different seasons of the year and also the presence of other possible radioactive pollutants. The use of this technique allows obtaining and studying the prints that generate the alpha particles that are emitted during the Rn-222 disintegration or by means of their descendants or predecessors; also allowing to discriminate between the short-range tracers or lineal type prints and other very different prints obtained during some of the measurements. The results analyzed according to proposed models are presented in this work. (author)

Radioactive substances in the Danish building materials

International Nuclear Information System (INIS)

Ulbak, K.

1986-01-01

Building materials as any other materials of natural occurrence contain small concentrations of natural radioactive elements. This natural radioactivity affects people inside buildings. This publiccation refers measurements of the Danish building materials, and radiation doses originating from this source affecting the Danish population are related to the other components of background radioactivity. (EG)

Phase distribution of ecologically controlled chemical elements in production of extraction phosphoric acid

International Nuclear Information System (INIS)

Kazak, V.G.; Agnelov, A.I.; Zajtsev, P.M.

1995-01-01

Content of 16 ecologically controlled chemical element (among them Cd, Sr, Th, U, V, Y) in solid and liquid phases of extraction phosphorus acid (EPA) production is determined. These elements are recommended to control by Scientific research institute of human ecology and environment to establish their extraction coefficients to phosphogypsum and EPA and optimal variant of production of ecologically sate phosphorus fertilizers. X-ray fluorescent, atomic-absorption and polarographic methods are used for analysis these elements

Transport of radioactive substances; Der Transport radioaktiver Stoffe

Energy Technology Data Exchange (ETDEWEB)

NONE

2014-12-15

The report on the transport of radioactive substances covers the following topics: facts on radioactive materials transport, safety of the transport of radioactive substances, legal regulations and guidelines: a multiform but consistent system, transport of nuclear fuels, safety during the transport of nuclear fuel, future transport of spent fuel elements and high-level radioactive wastes in Germany.

Chemical properties of some elements in a molten lithium chloride, potassium chloride eutectic (1962)

International Nuclear Information System (INIS)

Molina, R.

1961-12-01

The increasing use of molten media especially in chemical preparations and for certain technological applications, has made it more necessary to have a knowledge of the chemical properties of elements in these solvents. Structural studies on molten solutions show the existence of certain species such as ions and complexes known to exist in aqueous solutions. This fact, together with certain experiments on chemical reactions in molten media has led us to establish a comparison between these media and aqueous solutions. We wish to show that the same fundamental phenomena occur in these media as are found in the chemistry of aqueous solutions and that this makes it possible to predict certain reactions. We have taken as examples the chemical properties of vanadium, uranium and sulphur in a LiCl-KCl eutectic melted at 480 deg. C. The first problem is to identify the various degrees of oxidation of these elements existing in the solvent chosen. We have tried to resolve it by comparing the absorption spectra obtained in aqueous solution and in the molten eutectic. We consider the possibilities of this method in a chapter on absorption spectrophotometry in the LiCl-KCl eutectic. During the study of the chemical properties we stress the various methods of displacing the equilibria: complex formation, variation of the oxidation-reduction properties with complex formation. The complexes of the O 2- ion are considered in particular. The study of the exchange of this particle is facilitated by the use of a classification of some of its complexes which we call the pO 2- scale by analogy with the pH scale; the value pO 2- is defined by the relationship: pO 2- = log O 2- Similarly, the use of apparent potential diagrams pO 2- makes it possible to predict and to interpret reactions involving the simultaneous exchange of electrons and O 2- ions between the various degrees of oxidation of the same element. It is possible, by studying some reactions of this type between two elements

Element by element review of their atomic weights

International Nuclear Information System (INIS)

Peiser, H.S.; Holden, N.E.; Bievre, P. de

1984-01-01

The IUPAC 'standard' atomic weights of the terrestrially occurring chemical elements are individually reviewed tracing changes during the past 25 years. Emphasized is the relevant published scientific evidence which in each case constitutes the basis for the expert judgment by the responsible IUPAC Commission. It biennially reports on, recommends, and tabulates the best values of these atomic weights with an implied judgment of their individual reliability. In the introductory part of this Review the history of atomic-weight determinations is sketched. The IUPAC leadership in this data-evaluation project is described as it benefits science, technology, and trade. The remaining experimental uncertainties and natural variabilities are discussed. The treatment of abnormal materials is explained. The principal techniques for determining atomic weights are outlined. The effects of naturally occurring radioactive nuclides are characterized in their essentials. (author)

Radiochemical problems of radiation chemical synthesis in n, γ-field of nuclear reactor

International Nuclear Information System (INIS)

Mironov, V.P.; Frejdus, N.V.; Bugaenko, L.T.; Kalyazin, E.P.; Petryaev, E.P.

1981-01-01

A wide applicability of products of radiation chemical synthesis (RCS), using n, γ-irradiation, is limited by possible contamination of the latter with long-lived radioactive isotopes of chemical elements included in the composition of the reagent and compounds syntesized (chemically non-separable radionuclides - CNR). A technique of the determination of the limit accumulation CNR on the basis of radiation chemical parameters of the synthesis (radiation-chemical yield, the dose rate absorbed, singleness of purpose of RCS etc.) and radiochemical parameters of formation and accumulation of CNR (radiochemical yields of CNR in the products of radiolysis, neutron fluence, the reagent purity etc.) is suggested. The radiochemical evaluation of CNR accumulation (tritium and carbon-14), formed at the expense of activation with neutrons of chemical elements of water and organic substances, consisting of hydrogen, carbon and oxygen has shown that at relatively low yields of final products (> or approximately 3 molecules/100 eV) no accumulation of radionuclides in concentrations reaching the average admissible concentration takes place [ru

An Educational Card Game for Learning Families of Chemical Elements

Science.gov (United States)

Mariscal, Antonio Joaquin Franco; Martinez, Jose Maria Oliva; Marquez, Serafin Bernal

2012-01-01

This paper describes an educational card game designed to help high school students (grade 10, 15-16 years old) "understand," as opposed to memorize, the periodic table. The game may also be used to identify different chemical elements found in daily life objects. As an additional value, students learn the names and symbols of the displayed…

Radio elements / bottom salts separation by nano-filtration aided by complexation in a highly saline environment

International Nuclear Information System (INIS)

Gaubert, Eric

1997-01-01

This research thesis addresses the use of a membrane-based technique, nano-filtration, aided or not by complexation, for the processing of highly saline liquid effluents produced by radio-chemical decontamination. The objective is to separate non-radioactive elements (sodium nitrate) from radio-elements (caesium, strontium and actinides) in order to reduce the volume of wastes. Within the perspective of an industrial application, a system to concentrate the effluent is firstly defined. Different nano-filtration membranes are tested and reveal to be insufficient in highly saline environment. A stage of selective complexation of radio-elements is therefore considered before nano-filtration. The main factors affecting performance of nano-filtration-complexation (for a given membrane system) are identified: ionic force, pH, ligand content, trans-membrane pressure. Finally, a nano-filtration pilot is implemented to perform nano-filtration-complexation operations by remote handling on radioactive substances [fr

Chemical Technology Division. Annual technical report, 1995

International Nuclear Information System (INIS)

Laidler, J.J.; Myles, K.M.; Green, D.W.; McPheeters, C.C.

1996-06-01

Highlights of the Chemical Technology (CMT) Division's activities during 1995 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) methods for treatment of hazardous waste and mixed hazardous/radioactive waste; (3) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (4) processes for separating and recovering selected elements from waste streams, concentrating low-level radioactive waste streams with advanced evaporator technology, and producing 99 Mo from low-enriched uranium; (5) electrometallurgical treatment of different types of spent nuclear fuel in storage at Department of Energy sites; and (6) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems

Chemical Technology Division. Annual technical report, 1995

Energy Technology Data Exchange (ETDEWEB)

Laidler, J.J.; Myles, K.M.; Green, D.W.; McPheeters, C.C.

1996-06-01

Highlights of the Chemical Technology (CMT) Division`s activities during 1995 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) methods for treatment of hazardous waste and mixed hazardous/radioactive waste; (3) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (4) processes for separating and recovering selected elements from waste streams, concentrating low-level radioactive waste streams with advanced evaporator technology, and producing {sup 99}Mo from low-enriched uranium; (5) electrometallurgical treatment of different types of spent nuclear fuel in storage at Department of Energy sites; and (6) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems.

Influences of in-fuel physical-chemical processes on serviceability of energy reactor fuel elements

Energy Technology Data Exchange (ETDEWEB)

Bibilashvili, Yu K; Nekrasova, G A; Sukhanov, G I

1989-01-01

In-fuel physico-chemical processes and their effect on stress corrosion cracking of fuel element zirconium cladding are considered in the review. The mechanism of fission product release from the fuel is studied and the negative role of primarily iodine on the cladding corrosion process is demonstrated. Directions for improving the fuel element claddings and fuel to increase the fuel element serviceability are specified.

Influences of in-fuel physical-chemical processes on serviceability of energy reactor fuel elements

International Nuclear Information System (INIS)

Bibilashvili, Yu.K.; Nekrasova, G.A.; Sukhanov, G.I.

1989-01-01

In-fuel physico-chemical processes and their effect on stress corrosion cracking of fuel element zirconium cladding are considered in the review. The mechanism of fission product release from the fuel is studied and the negative role of primarily iodine on the cladding corrosion process is demonstrated. Directions for improving the fuel element claddings and fuel to increase the fuel element serviceability are specified

A conceptual chemical solidification/stabilization system to remediate radioactive raffinate sludge

International Nuclear Information System (INIS)

Carpenter, D.J.; Ansted, J.P.; Foldyna, J.T.

1994-01-01

Past operations at the U.S. Department of Energy's (DOE) Weldon Spring, Missouri, Superfund Site included the manufacture of nitroaromatic-based munitions and the production of uranium and thorium metal from ore concentrates. These operations generated a large quantity of diverse contaminated waste media including raffinate sludge, soil, sediment, and building debris. These various waste media are contaminated with varying amounts of radionuclides nitroaromatics, metals, metalloids, non-metals, polychlorinated biphenyls (PCBs) and asbestos. The volumes and diversity of contaminants and waste media pose significant challenges in identifying applicable remedial technologies, particularly for the excavation and treatment of the water-rich raffinate sludge. This paper presents the results of comprehensive efforts to develop a conceptual chemical solidification/stabilization (CSS) system to treat a variety of waste media. The emphasis of this paper is the treatment of a water-rich refractory raffinate sludge and site contaminated soils both radioactive and nonradioactive. The conceptual system design includes raffinate sludge excavation, dewatering, and CSS processing (reagent selection and formulation, reagent and waste storage and metering, and product mixing). Many innovations were incorporated into the design, producing a system that can process the various waste types. Additionally, the radioactive and hazardous constituents are sufficiently immobilized to allow the secured disposal in a waste cell of the treated product. The conceptual CSS system can also produce a variety of treated product types, ranging from a monolithic form to a compactible soil-like medium. The advantages of this system flexibility are also presented

The mobility of radioactive elements in a Uranium exploitation zone

International Nuclear Information System (INIS)

Bragea, M.; Toro, L.

2002-01-01

One of the purposes of this study is to gain knowledge on the possibilities of accumulations of the radioelements (2 38U , 2 32T h, 2 26R a) in a given ecosystem, and, particularly, the knowledge of the mechanisms implied in the transfer of these radioelements around the abandoned mining exploitations. The final purpose is the evaluation of the quantity of the radioelements susceptible to reach the man. The research is directed towards a quantitative evaluation of the transport rate of the contaminating element in the soil. There have been studied the surroundings of ore mines in the Boul Massif in Poiana Rusca Mountains in Romania. These exploitations had been closed and abandoned in 1990. From a geological point of view, the region is formed from crystalline schists, banat eruptive and sedimentary rocks. The iron deposit is totally situated in crystalline rocks in Poiana Rusca Mountains. The concentration of magnetite in the deposit is 25% with a relatively uniform dissemination in the ore. Brannerite (UCaThY)(TiFe) 2 O 6 , was also found in the same place. It is an ore should contain UO3 in proportion of up to about 33%. In 1963 there were stood out areas with radioactive minerals with gamma doses in the range of 500-9100 nGy/hour. In the same time, there were also identified a few points in which the concentration of thorium and uranium were significant. The areas with radioactive mineralizations were generally limited and strictly located in the limit of the iron ores deposit. By closing the mining activities huge quantities of waste rock stored in unprotected dump remained abandoned. As a result of the process of ore extraction, the waste rock and a very low percentage of metallic minerals were stored in tailing ponds, with a clay liner necessary to isolate the tailing from the reast of the aquifer

Automatized system of radioactive material analysis

International Nuclear Information System (INIS)

Pchelkin, V.A.; Sviderskij, M.F.; Litvinov, V.A.; Lavrikov, S.A.

1979-01-01

An automatized system has been developed for the identification of substance, element and isotope content of radioactive materials on the basis of data obtained for studying physical-chemical properties of substances (with the help of atomic-absorption spectrometers, infrared spectrometer, mass-spectrometer, derivatograph etc.). The system is based on the following principles: independent operation of each device; a possibility of increasing the number of physical instruments and devices; modular properties of engineering and computer means; modular properties and standardization of mathematical equipment, high reliability of the system; continuity of programming languages; a possibility of controlling the devices with the help of high-level language, typification of the system; simple and easy service; low cost. Block-diagram of the system is given

Cosmic disposal of radioactive waste

Energy Technology Data Exchange (ETDEWEB)

Inoue, Y; Morisawa, S [Kyoto Univ. (Japan). Faculty of Engineering

1975-03-01

The technical and economical possibility and safety of the disposal of highly radioactive waste into cosmos are reviewed. The disposal of highly radioactive waste is serious problem to be solved in the near future, because it is produced in large amounts by the reprocessing of spent fuel. The promising methods proposed are (i) underground disposal, (ii) ocean disposal, (iii) cosmic disposal and (iv) extinguishing disposal. The final disposal method is not yet decided internationally. The radioactive waste contains very long life nuclides, for example transuranic elements and actinide elements. The author thinks the most perfect and safe disposal method for these very long life nuclides is the disposal into cosmos. The space vehicle carrying radioactive waste will be launched safely into outer space with recent space technology. The selection of orbit for vehicles (earth satellite or orbit around planets) or escape from solar system, selection of launching rocket type pretreatment of waste, launching weight, and the cost of cosmic disposal were investigated roughly and quantitatively. Safety problem of cosmic disposal should be examined from the reliable safety study data in the future.

Some experiences with absorption, phonon Raman, and luminescence spectroscopic probes of crystal structure of f-element compounds

International Nuclear Information System (INIS)

Peterson, J.R.

1992-01-01

Structural information is crucial to the study and understanding of the basic chemical properties of the f elements. X-ray diffraction (XRD) techniques are usually used to obtain crystal structure information. However, the transuranium (5f) elements, because of their radioactivity and limited availability, present problems for standard XRD analysis. For some time now we have been developing and using various spectroscopic probes of crystal structure; an overview of our research in this area is presented here

Submicro and Nano Structured Porous Materials for the Production of High-Intensity Exotic Radioactive Ion Beams

CERN Document Server

Fernandes, Sandrina; Stora, Thierry

2010-01-01

ISOLDE, the CERN Isotope Separator On-line DEvice is a unique source of low energy beams of radioactive isotopes - atomic nuclei that have too many or too few neutrons to be stable. The facility is like a small ‘chemical factory’, giving the possibility of changing one element to another, by selecting the atomic mass of the required isotope beam in the mass separator, rather as the ‘alchemists’ once imagined. It produces a total of more than 1000 different isotopes from helium to radium, with half-lives down to milliseconds, by impinging a 1.4 GeV proton beam from the Proton Synchrotron Booster (PSB) onto special targets, yielding a wide variety of atomic fragments. Different components then extract the nuclei and separate them according to mass. The post-accelerator REX (Radioactive beam EXperiment) at ISOLDE accelerates the radioactive beams up to 3 MeV/u for many experiments. A wide international user radioactive ion beam (RIB) community investigates fundamental aspects of nuclear physics, particle...

The periodic system of chemical elements: old and new developments

International Nuclear Information System (INIS)

Kibler, M.

1987-09-01

Some historical facts about the construction of a periodic system of chemical elements are reviewed. The Madelung rule is used to generate an unusual format for the periodic table. Following the work of Byakov, Kulakov, Rumer and Fet, such a format is further refined on the basis of a chain of groups starting with SU(2)xS0(4.2)

The distributions of chemical elements and Caesium-137 in the Northern-Crimean canal ecosystem

International Nuclear Information System (INIS)

Lazorenko, G.

1998-01-01

The distributions in 1992-1995 of some chemical elements and 137 Cs concentrations in components of the Northern-Crimean Canal (NCC) ecosystem and agricultural fields of the Kherson District and the Northern Crimea irrigated by the Dnieper River water are presented in the work. Five main sampling were selected between the Kakhovka Reservior (at the beginning of the NCC) and the Karkinitsky Bay along the 150 km of the main Canal. Two additional stations were selected in discharge canals to study of the role of irrigated agricultural fields in the accumulation of 137 Cs and chemical elements from water. (author)

Chemical and nuclear properties of Rutherfordium (Element 104)

Energy Technology Data Exchange (ETDEWEB)

Kacher, Christian D. [Univ. of California, Berkeley, CA (United States)

1995-10-30

The chemical-properties of rutherfordium (Rf) and its group 4 homologs were studied by sorption on glass support surfaces coated with cobalt(II)ferrocyanide and by solvent extraction with tributylphosphate (TBP) and triisooctylamine (TIOA). The surface studies showed that the hydrolysis trend in the group 4 elements and the pseudogroup 4 element, lb, decreases in the order Rf>Zr≈Hf>Th. This trend was attributed to relativistic effects which predicted that Rf would be more prone to having a coordination number of 6 than 8 in most aqueous solutions due to a destabilization of the 6d_5/2 shell and a stabilization of the 7p_I/2 shell. This hydrolysis trend was confirmed in the TBP/HBr solvent extraction studies which showed that the extraction trend decreased in the order Zr>Hf>Rf?Ti for HBr, showing that Rf and Ti did not extract as well because they hydrolyzed more easily than Zr and Hf. The TIOA/HF solvent extraction studies showed that the extraction trend for the group 4 elements decreased in the order Ti>Zr≈Hf>Rf, in inverse order from the trend of ionic radii Rf>Zr≈Hf>Ti. An attempt was made to produce ²⁶³Rf (a) via the ²⁴⁸Cm(²²Ne, α3n) reaction employing thenoyltrifluoroacetone (TTA) solvent extraction chemistry and (b) via the ²⁴⁹Bk(¹⁸O,4n) reaction employing the Automated Rapid Chemistry Apparatus (ARCA). In the TTA studies, 16 fissions were observed but were all attributed to ²⁵⁶Fm. No alpha events were observed in the Rf chemical fraction. A 0.2 nb upper limit production cross section for the ²⁴⁸Cm(²²Ne, α3n)²⁶³Rf reaction was calculated assuming the 500-sec half-life reported previously by Czerwinski et al. [CZE92A].

Test plan for Digface Chemical and Radiation Assay System

International Nuclear Information System (INIS)

Akers, D.W.

1993-07-01

The Digface Chemical and Radiation Assay System (CRAS) Project will develop a sensor using Prompt Gamma Neutron Activation Analysis (PGNAA) that can detect the present of hazardous chemicals and radioactive materials. The CRAS is being designed for in situ assay of closed drums and contaminated soils for gamma-ray emitting radionuclides and hazardous elements. The CRAS is based upon the use of 252 Cf PGNAA with a germanium gamma-ray spectrometer as the analyzer. Tasks being performed include determining detection limits for a number of hazardous chemicals and assessing matrix and transmission effects through soil. Initial analyses suggest that the technique is applicable to a number of hazardous materials such as trichloroethane and carbon tetrachloride

Natural background radioactivity of the earth's surface -- essential information for environmental impact studies

International Nuclear Information System (INIS)

Tauchid, M.; Grasty, R.L.

2002-01-01

An environmental impact study is basically a study of change. This change is compared to the preexisting conditions that are usually perceived to be the original one or the 'pristine' stage. Unfortunately reliable information on the 'so called' pristine stage is far from adequate. One of the essential parts of this information is a good knowledge of the earth's chemical make up, or its geochemistry. Presently available data on the geochemistry of the earth's surface, including those related to radioactive elements, are incomplete and inconsistent. The main reason why a number of regulations are judged to be too strict and disproportional to the risks that might be caused by some human activities, is the lack of reliable information on the natural global geochemical background on which environmental regulations should be based. The main objective of this paper is to present a view on the need for complete baseline information on the earth's surface environment and in particular its geochemical character. It is only through the availability of complete information, including reliable baseline information on the natural radioactivity, that an appropriate study on the potential effect of the various naturally occurring elements on human health be carried out. Presented here are a number of examples where the natural radioactivity of an entire country has been mapped, or is in progress. Also described are the ways these undertakings were accomplished. There is a general misconception that elevated radioactivity can be found only around uranium mines, nuclear power reactors and similar nuclear installations. As can be seen from some of these maps, the natural background radioactivity of the earth's surface closely reflects the underlying geological formations and their alteration products. In reality, properly regulated and managed facilities, the levels of radioactivity associated with many of these facilities are generally quite low relative to those associated with

Determination of urine metabolites containing radioactivatable elements by molecular neutron activation analysis

International Nuclear Information System (INIS)

Blotcky, A.J.; Rack, E.P.

1986-01-01

As urine is a final stage for the metabolic pathways of essential trace elements or chemical toxins, it is becoming increasingly important to not only report levels of trace elements but to determine the molecular or ionic identity of these trace elements. For a biological system such as urine, a molecular neutron activation analysis (MONAA) approach must involve a deproteinization step, where necessary, to ensure that metabolites such as amino acids, bases, r nucleosides are not protein bound prior to chemical separation. This can involve the simple application of ammonia or acid hydrolysis. All separations for the metabolites containing the radioactivatable element must be performed prior to neutron irradiation and subsequent radioassay for the metabolite. Separation procedures can include high-pressure liquid chromotography (HPLC), ion-exchange chromatography, size exclusion chromatography, solvent extraction, and/or gas chromatography. After separation, the separated metabolite is neutron irradiated and and radioassayed for the radioactivity in the metabolite. A review of previous work involving the determination of hormonal iodine, iodoamino acids, chlorinated pesticides, trimethyl-selenonium, and selenoamino acids in urine is discussed

Water pollution by radioactive materials

International Nuclear Information System (INIS)

Bovard, P.

1976-01-01

Within the frame of the definition of a philosophy and politics of waste disposal and site selection, an analysis is made of the main elements of radioactive pollution of waters: sources of radioactivity, radionuclides classified according to their hazard, waste processing, disposal criteria and transfer processes in the compartments: water, suspended sediments, deposited sediments, biomass [fr

Issues of natural radioactivity in phosphates

International Nuclear Information System (INIS)

Schnug, E.; Haneklaus, S.; Schnier, C.; Scholten, L.C.

1996-01-01

The fertilization of phosphorus (P) fertilizers is essential in agricultural production, but phosphates contain in dependence on their origin different amounts of trace elements. The problem of cadmium (Cd) loads and other heavy metals is well known. However, only a limited number of investigations examined the contamination of phosphates with the two heaviest metals, uranium (U) and thorium (Th), which are radioactive. Also potassium (K) is lightly radioactive. Measurements are done n the radioactivity content of phosphates, P fertilizers and soils. The radiation doses to workers and public as well as possible contamination of soils from phosphate rock or fertilizer caused by these elements or their daughter products is of interest with regard to radiation protection. The use of P fertilizers is necessary for a sustainable agriculture, but it involves radioactive contamination of soils. The consequences of the use of P fertilizers is discussed, also with regard to existing and proposed legislation. 11 refs., 2 figs., 7 tabs

Radioactive sedimentary deposits concerning the coasts of the Camargue

International Nuclear Information System (INIS)

2000-01-01

CRII-RAD has detected abnormal levels of radioactivity on some beaches situated near the Espiguette lighthouse in the south-east coast of France. This document presents the in-situ measurements performed by IPSN. These results confirm a relevant increase of gamma radiation in sedimentary deposits. Chemical analyses have shown that this radioactivity is due to potassium 40 and radionuclides from thorium and uranium series. There is no doubt about the natural origin of this radioactivity but thorough geo-chemical studies are necessary to see whether these radioactive sands are a consequence of nearby industrial activities concerning ore dressing. (A.C.)

An investigation of changes in element distribution and chemical states during differentiation of embryonic stem cells

International Nuclear Information System (INIS)

Sugimoto, T.; Ide-Ektessabi, A.; Ishihara, R.; Tanigaki, M.

2004-01-01

Metallic elements and their organic compounds have dynamic regulatory functions in cells. In this study, we implemented a new approach to investigate the mechanism of differentiation of embryonic stem cells, by measuring and analyzing the change in distribution and chemical states of intracellular trace elements. We anticipate that trace metal elements and metalloproteins play important roles in the direction of differentiation, both as active centers, and as factors in the death of neural cells in neurodegenerative disorders. The aim of this study is to analyze the distribution and chemical states of trace elements during the process of differentiation of mouse embryonic stem cells, and to understand how these factors relate to the differentiation process. Using the experimental results, some previously unexplained points are considered, namely (1) how the intracellular elements change during the process of neuronal differentiation, and (2) what the optimal conditions of such elements are for neuronal differentiation. The information obtained during this study is relevant to nervous system development and evolution

An investigation of changes in element distribution and chemical states during differentiation of embryonic stem cells

Energy Technology Data Exchange (ETDEWEB)

Sugimoto, T.; Ide-Ektessabi, A. E-mail: h51167@sakura.kudpc.kyoto-u.ac.jp; Ishihara, R.; Tanigaki, M

2004-07-01

Metallic elements and their organic compounds have dynamic regulatory functions in cells. In this study, we implemented a new approach to investigate the mechanism of differentiation of embryonic stem cells, by measuring and analyzing the change in distribution and chemical states of intracellular trace elements. We anticipate that trace metal elements and metalloproteins play important roles in the direction of differentiation, both as active centers, and as factors in the death of neural cells in neurodegenerative disorders. The aim of this study is to analyze the distribution and chemical states of trace elements during the process of differentiation of mouse embryonic stem cells, and to understand how these factors relate to the differentiation process. Using the experimental results, some previously unexplained points are considered, namely (1) how the intracellular elements change during the process of neuronal differentiation, and (2) what the optimal conditions of such elements are for neuronal differentiation. The information obtained during this study is relevant to nervous system development and evolution.

Quantitative analysis of chemical elements in single cells using nuclear microprobe and nano-probe

International Nuclear Information System (INIS)

Deves, Guillaume

2010-01-01

The study of the role of trace elements at cellular level requires the use of state-of-the-art analytical tools that could achieve enough sensitivity and spatial resolution. We developed a new methodology for the accurate quantification of chemical element distribution in single cells based on a combination of ion beam analysis techniques STIM, PIXE and RBS. The quantification procedure relies on the development of a STIM data analysis software (Paparamborde). Validity of this methodology and limits are discussed here. The method allows the quantification of trace elements (μg/g) with a 19.8 % uncertainty in cellular compartments with mass below 0.1 ng. The main limit of the method lies in the poor number of samples that can be analyzed, due to long irradiation times required and limited access to ion beam analysis facilities. This is the reason why we developed a database for cellular chemical composition capitalization (BDC4). BDC4 has been designed in order to use cellular chemical composition as a tracer for biological activities and is expected to provide in the future reference chemical compositions for any cellular type or compartment. Application of the STIM-PIXE-RBS methodology to the study of nuclear toxicology of cobalt compounds is presented here showing that STIM analysis is absolutely needed when organic mass loss appears during PIXE-RBS irradiation. (author)

Use of radioactive tracers in chemical reactions

International Nuclear Information System (INIS)

Paci, B.

1979-01-01

A method for the determination of small quantities of nickel using radioactive tracers is presented. An analytical application of the displacement reaction between nickel and zinc ethylenediaminetetraacetate labeled with zinc-65 is pursued. This method is based on the extraction of radioactive zinc displaced by nickel from the zinc chelate into a dithizone-carbon tetracloride solution and the subsequent measurement of the activity of an aliquot of the extract. The method is very sensitive and nickel can be measured in concentrations as small as 0.1μg/ml or even less, depending on the specific activity of the radioreagent used. The precision and the accuracy of the method are determined. The problem of interferences, trying to eliminate them by using masking agents or by means of a previous separation between nickel and other interfering metals, is also investigated [pt

Study of commercial chemical additives for cementation of radioactive waste

International Nuclear Information System (INIS)

Mota Vieira, V.; Oliveira, C.C. de

2015-01-01

In this research it has been studied the effects of chemical additives (admixtures) in the cementation process of radioactive wastes, which are used to improve the properties of waste cementation process, both of the paste and of the solidified product. However there are a large variety of these materials that are frequently changed or taken out of the market, then it is essential to know the commercially available materials and their effects. The tests were carried out with a solution simulating the evaporator concentrate waste coming from PWR nuclear reactors. It was cemented using two formulations, A and B, incorporating higher or lower amount of waste, respectively. It was added chemical admixtures from two manufacturers (S and H), which were: accelerators, set retarders and superplasticizers. The experiments were organized by a factorial design 23. The measured parameters were the viscosity, the setting time, the paste and product density and the compressive strength. In this study we performed comparative analyzes of the results of compressive strength at age of 28 and 90 days and between the densities of the samples at the same ages. The compressive strength test at age of 28 days is considered a parameter essential issues related to security handling, transport and storage of cemented waste product. The results showed that the addition of accelerators improved the compressive strength of the cemented product, but presented lower values density products. (authors)

Contained x-ray diffraction goniometer for examination of radioactive materials

International Nuclear Information System (INIS)

Smith, P.K.; Osgood, B.C.; Blaser, D.E.; Howell, R.E.; Stuhler, H.; Stauver, J.

1987-11-01

Radioactive materials are being characterized for chemical form and certain physical properties with an x-ray diffraction goniometer customized for containment in a shielded alpha glovebox. A Siemens D500 goniometer was customized by Siemens to locate the associated electronics and x-ray generator outside the glovebox to minimize corrosion and facilitate maintenance. A graphite monochromator is used with a shielded scintillation detector to separate diffracted x-radiation from nuclear radiation. The diffraction system is computer automated for data acquisition and reduction. The facility is designed to handle primarily alpha- and beta-emitting samples with moderate neutron and gamma radiation. Samples containing plutonium, enriched uranium, and other transuranic elements are analyzed in support of site nuclear operations and development programs on nuclear waste, chemical separations, reactor fuels, and product forms

Dynamics of chemical elements in the fermentation process of ethanol production

International Nuclear Information System (INIS)

Nepomuceno, N.; Fernandes, E.A.N.; Bacchi, M.A.

1997-01-01

Brazil has become the largest producer of biomass ethanol derived from sugar cane. The industrial production is based on the fermentation of sugar cane juice by yeast, inside of large volume vats, in a fed-batch process that recycles yeast cells. To study the dynamics of chemical elements in each operating cycle, five stages of the fermentation process were considered: must, yeast suspension, wine, non-yeast wine and yeast cream. For this, a mass balance of the terrigenous elements, Ce, Co, Cs, Eu, Fe, Hf, La, Na, Sc, Sm, and Th, and the sugar cane plant elements, Br, K, Rb, and Zn, were established in fermentation vats of an industrial scale unit, with sampling undertaken during different climatic conditions (dry and rainy periods). A similar distribution of the sugar cane characteristics elements was found for the stages analysed, while for the terrigenous elements a trend of accumulation in the yeast cream was observed. Preferential absorption of Br, K, Rb, and Zn by yeast cells was indicated by the smaller concentrations observed in yeast suspension than in yeast cream. (author)

Radioactive resistance of memory elements

International Nuclear Information System (INIS)

Loncar, B.; Stankovic, S.; Novakovic, D.; Osmokrovic, P.

1998-01-01

In this paper, the results of semiconductor memories radioactive resistance examination (EPROM and EEPROM) are presented. Performance of semiconductor memories is most important, when working under high risk condition where there is an influence of radiation. This research is particularly interesting for specific applications in military industry and space technology. Therefore, the analysis of the degradation mechanism of these components as well as the possibilities to increase their radiation resistivity have been considered by many authors. The aim of this work is the examination of the reliability of EPROM and EEPROM characteristics under radiation. Total dose results are presented for the JL 27C512D EPROM and ST 24C02 EEPROM. There is evidence that EPROM are more sensitive to y radiation than EEPROM. The results obtained are analyzed theoretically via the interaction of gamma radiation with oxide layer. (authors)

Alpha radioactivity in Indian cement samples

International Nuclear Information System (INIS)

Nain, M.; Chauhan, R. P.; Chakarvarti, S. K.

2006-01-01

The essential constituents of radioactive and each of cements like lime, silica and alumina are derived from earth's crust in which radioactive elements like uranium, thorium etc are also present in varying amounts almost everywhere. These two elements are considered as the parent elements of uranium and thorium radioactive decay series in which radon and thoron are produced respectively as decay products. In the present study the samples of ordinary Portland cement , Portland pozzolana cement and some other cementious finishing materials like white cement, Plaster of Paris , cement putty etc were collected and analysed for radium and radon concentrations along with radon exhalation rates. Materials and Methods: Alpha sensitive LR-115 Type II plastic track detectors commonly known as S olid State Nuclear Track Detectors w ere used to measure the radium and radon concentration. The alpha particles emitted from the radon causes the radiation damaged tracks. The Chemical etching in NaOH at 60 C for about 90 minutes was done to reveal these latent tracks, which were then scanned and counted by an optical microscope of suitable magnification. By calculating the track density of registered tracks, the radon and radium concentrations along with exhalation rate of radon, were determined using required formulae. Results: The radon and radium concentration in various brands of cements found to vary from 333±9.9 to 506±13.3 Bq m-3 and from 3.7±0.1 to 5.6±0.2 Bq k g-1 while in various cementious finishing materials used in the construction, these were found to vary from 378±19.7 to 550±9.8 Bq m-3 and from 4.2±0.2 to 6.1±0.1 Bq Kg-1, respectively. Based on the data the mass and surface exhalation rates were also calculated Conclusion: The measurements indicate that there is marginal variation of the concentration of radium and radon in various brands of cements in India with lower levels in the cement samples having red oxide and higher levels in fly ash based cement

Study of the Treatment of the Liquid Radioactive Waste Nong Son Uranium Ore Processing

International Nuclear Information System (INIS)

Nguyen Ba Tien; Trinh Giang Huong; Luu Cao Nguyen; Harvey, L.K.; Tran Van Quy

2011-01-01

Liquid waste from Nong Son uranium ore processing is treated with concentrated acid, agglomerated, leached, run through ion exchange and then treated with H 2 O 2 to precipitate yellowcake. The liquid radioactive waste has a pH of 1.86 and a high content of radioactive elements, such as: [U] 143.898 ppm and [Th] = 7.967 ppm. In addition, this waste contains many polluted chemical elements with high content, such as arsenic, mercury, aluminum, iron, zinc, magnesium, manganese and nickel. The application of the general method as one stage precipitation or precipitation in coordination with BaCl 2 is not effective. These methods generated a large amount of sludge with poor settling characteristics. The volume of final treated waste was large. This paper introduces the investigation of the treatment of this liquid radioactive waste by the method of two stage of precipitation in association with polyaluminicloride (PAC) and polymer. The impact of factors: pH, neutralizing agents, quantity of PAC and polymer to effect precipitation and improve the settling characteristics during processing was studied. The results showed that the processing of liquid radioactive waste treatment through two stages: first stage at pH = 3 and the second stage at pH = 8.0 with limited PAC and polymer (A 101) resulted in significant reduced volume of the treated waste. The discharged liquid satisfied the requirement of the National Technical Regulation on Industrial Waste Water (QCVN 24:2009). (author)

Recommendations for sampling for prevention of hazards in civil defense. On analytics of chemical, biological and radioactive contaminations. 2. ed.; Empfehlungen fuer die Probenahme zur Gefahrenabwehr im Bevoelkerungsschutz. Zur Analytik von chemischen, biologischen und radioaktiven Kontaminationen

Energy Technology Data Exchange (ETDEWEB)

Bachmann, Udo; Derakshani, Nahid; Drobig, Matthias; Koenig, Mario; Mentfewitz, Joachim; Prast, Hartmut; Uelpenich, Gerhard; Vidmayer, Marc; Wilbert, Stefan; Wolf, Manfred

2016-07-01

The recommendations for sampling for prevention of hazards in civil defense (analytics of chemical, biological and radioactive contaminations) cover the following topics: Requirements for sampling, description of the materials (chemical, biological and radioactive contaminated materials), decontamination, sample transport and protocol documents.

studies on the fixation of chemical and radioactive contaminants by natural and artificial compounds

International Nuclear Information System (INIS)

Mourad, G.A.M.

2006-01-01

the main objective of the work presented in this is to study the adsorption of U(VI), Cr(VI) and Gd (lll) from aqueous medium using modified sorel's cement as artificial adsorbents. the thesis is classified into three chapters; namely ,introduction ,experimental and results and discussion. the first chapter, i ntroduction , includes chemical and radioactive contaminant, some aspects of the properties and aqueous chemistry of uranium, chromium and gadolinium . the separation of different pollutant and their methods of separation based on the types of adsorbents, and the theoretical background of adsorption isotherms, kinetics and ion diffusion as well as literature survey which is related to the present work are given.the second chapter, e xperimental , contains the different materials employed, their chemical purity, and a detailed description for instruments used are given.the third chapter. r esults and discussion i ncludes the experimental results obtained and their interpretation .this chapter is classified into three main parts; namely, characterization, equilibrium and kinetic investigations

Use of radioactive tracers in chemical reactions

International Nuclear Information System (INIS)

Paci, B.; Saiki, M.

1979-01-01

A method for the determination of small quantities of nickel by using radioactive tracers is presented. An analytical application of the displacement reaction between and zinc-ethylenediaminetetraacetate, (Zn-EDTA), labelled with 65 Zn is investigated. This method is based on the extraction of radioactive zinc, displaced by nickel from the zinc chelate, into a dithizone-carbon tetrachloride solution and the subsequent measurement of the activity of an aliquot of the extract. It is shown that the method is very sentitive and nickel can be measured in concentrations as small as 0,1μg/ml or even less, depending on the specific activity of the radioreagent used. The precision and accuracy of the method are determined. An attempt to eliminate the problem of interference by using masking agents or by means of a previous separation of nickel and other interfereing metals, is also made. (Author) [pt

[Microbiological Aspects of Radioactive Waste Storage].

Science.gov (United States)

Safonov, A V; Gorbunova, O A; German, K E; Zakharova, E V; Tregubova, V E; Ershov, B G; Nazina, T N

2015-01-01

The article gives information about the microorganisms inhabiting in surface storages of solid radioactive waste and deep disposal sites of liquid radioactive waste. It was shown that intensification of microbial processes can lead to significant changes in the chemical composition and physical state of the radioactive waste. It was concluded that the biogeochemical processes can have both a positive effect on the safety of radioactive waste storages (immobilization of RW macrocomponents, a decreased migration ability of radionuclides) and a negative one (biogenic gas production in subterranean formations and destruction of cement matrix).

Development of the chemical stabilization and solidification process for the treatment of radioactive raffinate sludges at the DOE Weldon Spring Site Remedial Action Project

International Nuclear Information System (INIS)

Cole, P.M.; Kakaria, V.; Enger, J.

1996-01-01

Chemical Solidification and Stabilization (CSS) is the mixing of chemical reagents with waste to solidify and chemically stabilize the contaminated material. The resulting product is resistant to leaching of certain contaminants. CSS treatment using Class C fly ash and Portland cement was chosen as the most feasible method for treatment of the chemically and radioactively contaminated sludge (raffinate) contained in raffinate pits on the Weldon Spring Site Remedial Action Project (WSSRAP) located outside of St. Louis, Missouri. Due to the uniqueness of the material, substantial bench-scale testing was performed on the raffinate to better understand its properties. Similarly, due to mixed results in the application of CSS treatment to radioactive materials, a pilot-scale testing facility was built to verify bench testing results and to establish and quantify design parameters for the full-scale CSS production facility. This paper discusses the development of the pilot-scale testing facility, the testing plan, and the results of the testing activities. Particular attention has been given to the applicability of the CSS treatment method and to the value of pilot-scale testing

Radioactive waste management

International Nuclear Information System (INIS)

Blomek, D.

1980-01-01

The prospects of nuclear power development in the USA up to 2000 and the problems of the fuel cycle high-level radioactive waste processing and storage are considered. The problems of liquid and solidified radioactive waste transportation and their disposal in salt deposits and other geologic formations are discussed. It is pointed out that the main part of the high-level radioactive wastes are produced at spent fuel reprocessing plants in the form of complex aqueous mixtures. These mixtures contain the decay products of about 35 isotopes which are the nuclear fuel fission products, about 18 actinides and their daughter products as well as corrosion products of fuel cans and structural materials and chemical reagents added in the process of fuel reprocessing. The high-level radioactive waste management includes the liquid waste cooling which is necessary for the short and middle living isotope decay, separation of some most dangerous components from the waste mixture, waste solidification, their storage and disposal. The conclusion is drawn that the seccessful solution of the high-level radioactive waste management problem will permit to solve the problem of the fuel cycle radioactive waste management as a whole. The salt deposits, shales and clays are the most suitable for radioactive waste disposal [ru

Introducing radioactivity monitoring systems in the production of steel

International Nuclear Information System (INIS)

Sofilic, T.; Marjanovic, T.; Rastovcan-Mioc, A.

2005-01-01

Over the last twenty years, a significant number of cases of radioactive pollution has been recorded in metallurgical processes. However, it is not certain whether the pollution was caused by increased uncontrolled disposal of waste containing radionuclides or whether it was the result of increased radioactivity monitoring and control of metallic scrap. Many metal producers in the world have therefore implemented systematic monitoring of radioactivity in their production processes. Special attention was given to monitoring radioactivity in steel making processes, which is still the most applied construction material with an annual output of over billion tonnes all over the world. Drawing on the experience of the best known steel producers in Europe and world, Croatian steel mills find it necessary and justified to introduce radioactivity monitoring and control systems of radioactive elements in steel scrap, semi-finished and finished products. The aim of this paper is to point out the need to introduce the radioactivity monitoring and control in steel and steel-casting production, and to inform experts in Croatian steel mills and foundries about potential solutions and current systems. At the same time, we wanted to demonstrate how implementation of monitoring equipment can improve quality management and environmental management systems. This would render Croatian products competitive on the European market both in terms of physical and chemical properties and in terms of product quality certificates and radioactivity information. Since we lack our own standards and regulations to control both domestic and imported steel scrap, semi-finished products (crude steel, hot and cold rolled strip) and finished products, we need apply current international recommendations and guidelines, until we design our own monitoring system and adopt relevant legislation on the national level. This paper describes basic types of radioactivity monitoring and control systems, the most

Significance of chemotoxic admixtures in radioactive wastes

International Nuclear Information System (INIS)

Merz, E.R.

1989-01-01

The double hazard potential of mixed wastes is characterized by several criteria: radioactivity on the one hand, and chemical toxicity, in flammability, corrosiveness as well as chemical reactivity on the other. The author argues that mixed wastes assigned for ultimate disposal should therefore be thoroughly detoxified, inertized, or mineralized, prior to conditioning and packaging. Strategies and techniques are presented which ensure the elimination of hazardous organic chemicals and minimizing waste volumes to be disposed of. Advantage can be taken of mixing mineralized filter dusts, arising in the combustion of hazardous chemical wastes with low-activity inertized radioactive wastes as a solidifying reagent. Simultaneous geological disposal of such mixed waste is feasible without any drawbacks

Study of the mineralization of coral implanted in vivo by radioactive tracers

International Nuclear Information System (INIS)

Irigaray, J.L.; Sauvage, T.; Oudadesse, H.; El Fadl, H.

1993-01-01

Coral may be used as a substitution biomaterial to the bone graft, due to its physico-chemical and architectural properties. The coral, after its implantation 'in vivo' reaches a mineral composition and crystalline structure comparable to those of a bone. The calcification mechanism of this implant is studied using 45 Ca as radioactive tracer. The atomic elements contained in the initial coral were analysed in function of the time spent in the body, by marking the calcium and the strontium contained in its structure. (K.A.) 8 refs.; 6 figs.; 4 tabs

Yttrium separation of Xenotime waste in Pitinga (Brazil), in order to obtain rare earth elements

International Nuclear Information System (INIS)

Melo.

1996-01-01

The xenotime (YPO 4 and rare earth elements) found in the mine of Pitinga, Amazonas State, Brazil, has its origin in a primal depository ('eluvio' kind) of cassiterite, having considerable quantities of zirconite, ilmenite, topaz and niobates-tantalates. This xenotime has different characteristics in relation of the depositories that exist in other countries for presenting more concentration of rare earth heavy oxides. The mineralization of this cassiterite is problematic, because of the high level of radioactive elements. In the present work, we will process only the xenotime. The separation of rare earth elements is very difficult due to their great chemical similarity. For a more exactly determination, it is necessary to separate them at least of the macron constituents of the sample. As the Yttrium is considerate one of the rare earth elements, due to its chemical similarity, we can understand the difficulty of a chemical separation, mainly when this one is also a macro constituent of the sample, as in the case of xenotime. The process of separation will be based on the little difference that exists between the constants of complexation and the fluoride. (authors). 5 refs., 1 fig., 2 tabs

Geological Disposal of Radioactive Waste

International Nuclear Information System (INIS)

Dody, A.; Klein, Ben; David, O.

2014-01-01

Disposal of radioactive waste imposes complicated constrains on the regulator to ensure the isolation of radioactive elements from the biosphere. The IAEA (1995) states that T he objective of radioactive waste management is to deal with radioactive waste in a manner that protects human health and the environment now and the future without imposing undue burdens on future generation . The meaning of this statement is that the operator of the waste disposal facilities must prove to the regulator that in routine time and in different scenarios the dose rate to the public will not exceed 0.3 mSv/y in the present and in the future up to 10,000 years

The calculation of radiation fields of chemical contamination of nature with the use of a digital model

International Nuclear Information System (INIS)

Mehtiev, D.S.; Sultanov, D.A.; Azizov, B.M.

2008-01-01

Danger of contamination of the environment by convection of air and fluid transport in porous media arise while disposing of waste radioactive isotopes and chemical industry waste in underground deep-seated horizons. As a result there is eventually observed the formation of radioactive fields of local character. A lot of methods using for defining of radioactive fields of objects of the similar type, basically are based on the registration particles and quantum, emitted by nuclear of the corresponding elements in their radioactive decay. This is especially important for objects intended for placement in the mass of low permeable rocks, such as rock type. On the base of complex using of modern information basis created the model of induced radiation field of environment

Few atom chemistry of the trans actinide element rutherfordium (Rf)

International Nuclear Information System (INIS)

Nagame, Y.

2002-01-01

Studies of chemical properties of the trans actinide elements - starting with element 104 (Rf) - offer the unique opportunity to obtain information about trends in the Periodic Table at the limits of nuclear stability and to assess the magnitude of the influence of relativistic effects on chemical properties. To explore experimentally the influence of relativistic effects of electron shell structure, we study the chemical properties of the trans actinide elements. So far, we have developed some experimental apparatuses for the study of chemical properties of the trans actinide elements: a beam-line safety system for the usage of the gas-jet coupled radioactive 248 Cm target chamber for the production of trans actinides, a rotating wheel catcher apparatus for the measurement of α particles and spontaneous fission decay of trans actinides and an automated rapid chemical separation apparatus based on high performance liquid chromatography. The trans actinide nuclide, the element 104, 261 Rf (t 1/2 = 78 s) has been successfully produced via the reactions of 248 Cm( 18 O,5n) at the JAERI (Japan Atomic Energy Research Institute) tandem accelerator. The evaluated production cross section was about 10 nb, indicating that the production rate was approximately 2 atoms per min. Because of the short half-life and the low production rate of Rf, each atom produced decays before a new atom is synthesized. It means that any chemistry to be performed must be done on an 'atom-at-a-time' basis. Therefore rapid, very efficient and selective chemical procedures are indispensable to isolate the desired trans actinide 261 Rf. To perform fast and repetitive ion-exchange separation of Rf, we have developed the apparatus AIDA (Automated Ion exchange separation system coupled with the Detection apparatus for Alpha spectroscopy). Recently, ion-exchange behavior of Rf in acidic solutions has been studied with AIDA, and the results indicate that anion-exchange behavior of Rf is quite similar

Chemical elements in Leucaena leucocephala leaves of riparian zones of the municipality of Piracicaba, São Paulo, Brazil; Elementos químicos em folhas de Leucaena leucocephala de zonas ripárias do município de Piracicaba, São Paulo, Brasil

Energy Technology Data Exchange (ETDEWEB)

França, Elvis J. de; Fernandes, Elisabete A.N.; Lira, Marcelo G.; Ferreira, Fabiano S.; Cavalca, Isabel P.O.; Rodrigues, Vanessa S.; Camilli, Leandro, E-mail: ejfranca@yahoo.com.br, E-mail: liramarcelo@hotmail.com, E-mail: biologofabiano10@gmail.com [Centro Regional de Ciências Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

2017-07-01

The species Leucaena leucocephala can be found in several riparian ecosystems, acting as one of the main invasive and harmful species for the forest restoration of the permanent preservation areas. It has also been studied for the phytoremediation of some chemical elements, due to their potential accumulation of chemical substances. Therefore, the present study aimed to evaluate the accumulation of chemical elements in leaves of Leucaena leucocephala trees by Instrumental Neutronic Activation Analysis - INAA. Samples of leaves were collected in eight samples from riverside areas of the Piracicaba Municipality, São Paulo, Brazil, during the dry and rainy season. After collection, washing with water and drying in a forced circulation oven, the samples were comminuted and encapsulated in polyethylene capsules and subjected to a thermal neutron flux of 10{sup 13} cm{sup -2}s{sup -1} for 8 hours in the Nuclear Research Reactor IEA-R1 of IPEN / CNEN. Thermal neutron flux monitoring was performed by Ni-Cr alloy fragments with known concentrations of the chemical monitors elements. After measurements of radioactivity induced by HPGe detectors, the concentrations of the chemical elements were calculated by the k0 method using the Quantu computer program. Certified reference materials were also analyzed for quality assurance of the analytical procedure. The results indicated high concentrations of La and lanthanoids (Ce, Eu, Sm, Tb and Yb) in leaves of L. leucocephala in both periods analyzed. It was possible to observe a decrease in the concentrations of the chemical elements in the rainy season, probably associated to the washing of the geological material deposited on the leaves of the trees by the rains, except for K, Mo, Rb, Sb and Zn, whose values remained or increased in the leaves collected during the rainy season. Considering the constant leaf production, L. leucocephala can greatly affect the cycling of chemical elements due to its accumulation capacity

Radioactive-site-remediation technologies seminar. Speaker slide copies

International Nuclear Information System (INIS)

1992-06-01

The contents of this report include the following: approaches to sampling radioactive heterogeneous waste; soil characterization methodology for determining application of soil washing; vorce (volume reduction/chemical extraction) program; treatment of radioactive compounds in water; polymer solidification of low-level radioactive, hazardous, and mixed waste; in situ vitrification of soils contaminated with radioactive and mixed wastes; decontamination of contaminated buildings; incineration of radioactive waste; in situ stabilization/solidification with cement-based grouts; environmental restoration and waste management; removal of contaminants from soils by electrokinetics; and treatment, compaction, and disposal of residual radioactive waste

Radionuclides and trace elements in middle Chesapeake Bay sediments

International Nuclear Information System (INIS)

Gavrilas, M.

1988-01-01

Sediments play an important role in aquatic ecology by serving as a repository for radioactive substances and for soluble chemical pollutants that they may transport over considerable distances and may pass to a higher trophic level by way of bottom-feeding biota. The Chesapeake Bay is a moderately stratified, drowned river valley estuary. The oscillatory flood and ebb of the tidal currents are the most obvious motions in the bay and its tributary estuaries. It is considered that the distribution of most of the pollutants, once diluted by the mixing action of the tidal flow, remains relatively constant for many miles up and down the bay. This paper documents the present status of the radioactivity and of trace elements in sediment samples collected in March 1986 from and extended area around the Calvert Cliffs Nuclear Power Plant

Radioactive waste disposal. Facts, problems and responsible action

International Nuclear Information System (INIS)

Finckh, E.; Seitz, M.

1994-01-01

In a first part, natural science and technology aspects of waste management are outlined: basic concepts of radioactivity; properties, detection and primary effects of radioactive radiation; biological effect of radioactivity and radiation; general geological bases; composition of spent fuel elements; interim storage and transport; reprocessing of spent fuels; classification and treatment of radioactive wastes; emplacement possibilities for radioactive wastes; possible ways of radionuclides from the repository back into the biosphere; comparative consideration of the risks involved in nuclear waste management. The second part of the paper deals with ethical and theological aspects of radioactive waste management. (orig./HP) [de

Chemical species of plutonium in Hanford radioactive tank waste

International Nuclear Information System (INIS)

Barney, G.S.

1997-01-01

Large quantities of radioactive wastes have been generated at the Hanford Site over its operating life. The wastes with the highest activities are stored underground in 177 large (mostly one million gallon volume) concrete tanks with steel liners. The wastes contain processing chemicals, cladding chemicals, fission products, and actinides that were neutralized to a basic pH before addition to the tanks to prevent corrosion of the steel liners. Because the mission of the Hanford Site was to provide plutonium for defense purposes, the amount of plutonium lost to the wastes was relatively small. The best estimate of the amount of plutonium lost to all the waste tanks is about 500 kg. Given uncertainties in the measurements, some estimates are as high as 1,000 kg (Roetman et al. 1994). The wastes generally consist of (1) a sludge layer generated by precipitation of dissolved metals from aqueous wastes solutions during neutralization with sodium hydroxide, (2) a salt cake layer formed by crystallization of salts after evaporation of the supernate solution, and (3) an aqueous supernate solution that exists as a separate layer or as liquid contained in cavities between sludge or salt cake particles. The identity of chemical species of plutonium in these wastes will allow a better understanding of the behavior of the plutonium during storage in tanks, retrieval of the wastes, and processing of the wastes. Plutonium chemistry in the wastes is important to criticality and environmental concerns, and in processing the wastes for final disposal. Plutonium has been found to exist mainly in the sludge layers of the tanks along with other precipitated metal hydrous oxides. This is expected due to its low solubility in basic aqueous solutions. Tank supernate solutions do not contain high concentrations of plutonium even though some tanks contain high concentrations of complexing agents. The solutions also contain significant concentrations of hydroxide which competes with other

Radioactive waste management and regulation

International Nuclear Information System (INIS)

Willrich, M.; Lester, R.K.; Greenberg, S.C.; Mitchell, H.C.; Walker, D.A.

1977-01-01

Purpose of this book is to assist in developing public policy and institutions for the safe management of radioactive waste, currently and long term. Both high-level waste and low-level waste containing transuranium elements are covered. The following conclusions are drawn: the safe management of post-fission radioactive waste is already a present necessity and an irreversible long-term commitment; the basic goals of U.S. radioactive waste policy are unclear; the existing organization for radioactive waste management is likely to be unworkable if left unchanged; and the existing framework for radioactive waste regulation is likely to be ineffective if left unchanged. The following recommendations are made: a national Radioactive Waste Authority should be established as a federally chartered public corporation; with NRC as the primary agency, a comprehensive regulatory framework should be established to assure the safety of all radioactive waste management operations under U.S. jurisdiction or control; ERDA should continue to have primary government responsibility for R and D and demonstration of radioactive waste technology; and the U.S. government should propose that an international Radioactive Waste Commission be established under the IAEA

BioRadBase: A database for bioremediation of radioactive waste ...

African Journals Online (AJOL)

Radioactive waste from different sectors such as nuclear energy, health care and food has become a discernible part of our environment. Several dumping methods are in routine practice to dispose radioactive wastes. Huge chemical and energy input in various skillful physico-chemical methods has limited their use while ...

Measurement of natural radioactivity and elemental analysis in plant samples

International Nuclear Information System (INIS)

Chauhan, Pooja; Chauhan, R.P.

2015-01-01

Radioactivity is a major source of worldwide human exposure to ionizing radiation, a fraction of which results from such anthropogenic activities that are not subjected to regulatory radiological safety standards. In addition to being the main source of continuous radiation exposure to the human, soil acts as a medium of migration for transfer of radio nuclides to the biological systems and hence, it is the basic indicator of radiological contamination in the environment. Soil to plant is major pathway for accumulation of radionuclide to human being. The specific metabolic character of the plant species may lead to accumulation of radio-nuclides in their organs which may further depend upon the physico-chemical characteristics of the soil. A fraction of these heavy metals in soil can transfer to plant through various metabolic activities occurring in plants. Heavy metal-contaminated soil is one of the widespread global problems. Migration and accumulation of contaminants in the soil-plant system is complex, and assessment models commonly utilize a soil-plant concentration ratio, referred to as a transfer factor (TF), to estimate the transportation of radionuclides through the food chain. This ratio describes the amount of radionuclide expected to enter a plant from soil. (author)

Specialized equipment needs for the transportation of radioactive material

International Nuclear Information System (INIS)

Condrey, D.; Lambert, M.

1998-01-01

To ensure the safe and reliable transportation of radioactive materials and components, from both the front and back-end of the nuclear fuel cycle, a transport management company needs three key elements: specialized knowledge, training and specialized equipment. These three elements result, in part, from national and international regulations which require specialized handling of all radioactive shipments. While the reasons behind the first two elements are readily apparent, the role of specialized equipment is often not considered until too late shipment process even though it plays an integral part of any radioactive material transport. This paper will describe the specialized equipment needed to transport three of the major commodities comprising the bulk of international nuclear transports: natural uranium (UF6), low enriched uranium (UF6) and fresh nuclear fuel. (authors)

Behaviors and chemical forms of radionuclides in seawater

International Nuclear Information System (INIS)

Honda, Yoshihide

1981-01-01

Although the radionuclides introduced into the marine environment from various sources and routes are finally distributed among the components of the marine ecosystem, the residence time is one of the most useful measures of the reactivity of an element in the oceanic chemical system. Heavy metals such as Mn, Fe, Co and Zn which have shorter residence times, reveal more complicated behaviours in relation to marine radioecological interest than alkaline earth element such as Sr which has a longer residence time. The possible physico-chemical forms of radionuclides in the oceans are usually classified into three categories, that is, species in true solution, colloidal species, and particulate forms. The modeling to study the dispersion of radionuclides introduced into the marine environment can be approached with the aid of the knowledge of behaviors of their stable counterparts in seawater. The different physico-chemical forms between stable and radioactive nuclides in seawater may cause different biological concentration of the element. To realize the chemical speciation of radionuclides in the marine environment, it is also important in thermodynamical calculation to consider heterogeneous interfaces where cause raising the concentration of reactants in seawater, especially in the coastal waters. In the discussion on the primary factors that can affect the elemental distribution in the marine environment, primary productivity and bacterial activity are emphasized for the transformation of physicochemical states of radionuclides in the marine environment. Finally, the radioecological differences between radiocobalt in organic complexed and ionic forms were demonstrated in the experiments on the uptake and elimination of radiocobalt by mussels. (J.P.N.)

Influence of non-radioactive payload parameters on radioactive shipping packages

International Nuclear Information System (INIS)

Drez, P.E.; Murthy, D.V.S.; Temus, C.J.; Quinn, G.J.; Ozaki, C.

1989-01-01

The transport of radioactive waste materials in radioactive material (RAM) packages involves two components: the packaging used for transportation, and the waste which forms the payload. The payload is usually comprised of non-radioactive materials contaminated with radionuclides. The non-radionuclide payload characteristics can often be a controlling factor in determining the restrictions imposed on the certification of the package. This paper describes these package/payload interactions and the limiting parameters for the Transuranic Package Transporter-II (TRUPACT-II), designed for the transportation of Contact Handled Transuranic (CH-TRU) waste. The parameters discussed include the physical and chemical form of the payload, the configuration of the waste, and resulting gas generation and gas release phenomena. Brief descriptions of the TRUPACT-II package and its payload are presented initially

Determination of Natural Radioactivity in Groundwater in Tanke ...

African Journals Online (AJOL)

User

A study of the radioactivity in groundwater from Tanke-Ilorin, Nigeria, has been carried out. Ten water ... et al., 1995) and soil/water samples obtained around production .... radioactive elements 238U and 232Th. The activity of naturally ...

Ventilation of radioactive enclosures

International Nuclear Information System (INIS)

Caminade, F.; Laurent, H.

1957-01-01

Mechanical, physical and chemical manipulations on radioactive products must be carried out in properly ventilated enclosed places. The air extracted can only be discharged into the atmosphere after a correct filtration. The power of the ventilation systems is a function of the dimensions and purpose of the enclosure? The choice of types of filter is determined by the physical state and chemical nature of the radioactive materials to be manipulated. This study deals with the individual equipment of small installations: glove boxes, manipulation boxes with outside control and, if necessary, production chambers (maximum useful volume: 5 m 3 ). The performances of three types of 'ventilators', and the modifications provided by the addition of filters, are measured and compared. (author) [fr

Disposal method of radioactive wastes

International Nuclear Information System (INIS)

Uetake, Naoto; Fukazawa, Tetsuo.

1986-01-01

Purpose: To improve the safety of underground disposal of radioactive wastes for a long period of time by surrounding the periphery of the radioactive wastes with materials that can inhibit the migration of radioactive nuclides and are physically and chemically stable. Method: Hardening products prepared from a water-hardenable calcium silicate compound and an aqueous solution of alkali silicate have compression strength as comparable with that of concretes, high water tightness and adsorbing property to radioactive isotopes such as cobalt similar to that of concretes and they also show adsorption to cesium which is not adsorbed to concretes. Further, the kneaded slurry thereof is excellent in the workability and can be poured even into narrow gaps. Accordingly, by alternately charging granular radioactive wastes and this slurry before hardening into the ground, the radioactive wastes can be put to underground disposal stably with simple procedures. (Kamimura, M.)

Radionuclides and heavy elements containing in the soil and vegetation in the area of Didmay tailing pit

International Nuclear Information System (INIS)

Razikov, Z.A.; Yunusov, M.M.

1997-01-01

In this article on the base of carried out investigations authors made conclusion on effectiveness of obtaining of geo botanical methods of territory investigation adjoining to the tailing pits. With the purpose of decreasing of radionuclides and heavy metals concentration in the soil it was determined for this spot the plant-indicators and association which can accumulate radioactive and attendant them chemical elements

Measurement of Radioactivity in Some Croatian Regions

International Nuclear Information System (INIS)

Orehovec, Z.; Ilijas, B.; Bokan, S.

2001-01-01

Full text: After Government of Canada expressed its suspicion that Canadian soldiers who were included in UNPROFOR mission in Croatia were exposed to increased radioactivity and possible some chemical influences, a large action of measuring and sampling was undertaken. Canadian and Croatian experts were working together and a very large number of samples was collected. Measurements of alpha, beta and gamma radioactivity on terrain, as well as later analysis of samples showed no increased radioactivity or any other signs of radioactive contamination. The conclusion is that any possible diseases of Canadian soldiers can not originate from radiation or radioactive contamination in Croatia. (author)

Long-term evolution of radio-active waste storage in geological formations: analogy with the weathering of mineral deposits

International Nuclear Information System (INIS)

Cantinolle, P.; Griffault, L.; Jebrak, M.

1986-01-01

The aim of this study was to select examples of mineral deposits and their weathering environment, showing the long-term behaviour, in geological time, measuring (area, volume) some constituent elements of radio-active waste storage subject to the hazards of hydrogeochemical weathering. Initially, a feasibility study was made to collate data available within the BRGM (mining group and public service) and from literature dealing with weathering of deposits. It was thus discovered that the analogy between radio-active waste storage and mineral deposits could be approached in two different yet complementary ways: - one approach is to observe the behaviour of a mineral deposit in relation to the country rocks. For this a bibliographic metallogenic study was made. The other approach is to observe the behaviour of chemical elements during deposition of a mineral deposit whose genesis is similar to the spatial and thermal environment of a deposit of radio-active waste in a geological formation. For this two sites were selected corresponding to hydrothermal systems showing strong analogies to those expected in the neighbourhood of the storage sites. These two sites, Langenberg in the Vosges and La Telhaie in Brittany, were the subject of complementary analytical work [fr

An investigation of trace and radioactive elements in Elgash area

International Nuclear Information System (INIS)

Abdel Rahman, Babikir Ali

1997-08-01

the area is suitable for drinkking as well as a source of important nutritional elements for cultivation. These values contents of soil, plant and water of the area were found to be lie within acceptable ranges, in addition to that the area contains a very low amounts of pollutants such as lead compared to the world-wide range. The sampling sites were surveyed using a portable scintillometer hand-held at one meter above the ground level. Rock samples collected from jebel Glusi and Alttaka, and soil samples from the river were analyzed using gamma ray spectrometry so as to estimate- and for the fiirts time-the radiactivity concentaration which will contribute towards an establishment of a country radiation map. It is found that the activity concentration of 226 Ra, 228 Ra and 40 K studied in soil samples ranged from 13.0-30.7 Bq/Kg, 12.5-59.9 Bq/Kg and 283.0-461.4 Bq/Kg, respectively. The calculated dose rate due to gamma radiation form the ground at one meter height ranged between 23.5 and 37.5 nGy/h with an average value of 37.5 nGy/h which correspond to annual dose equivalent of 229.9 μSv. This shows that the level of radioactivity in the surveyed area lies within the worldwide range of normal background radiation. (Author)

An investigation of trace and radioactive elements in Elgash area

Energy Technology Data Exchange (ETDEWEB)

Abdel Rahman, Babikir Ali [Department of Chemistry, Faculty of Science, University of Khartoum, Khartoum (Sudan)

1997-08-01

the area is suitable for drinkking as well as a source of important nutritional elements for cultivation. These values contents of soil, plant and water of the area were found to be lie within acceptable ranges, in addition to that the area contains a very low amounts of pollutants such as lead compared to the world-wide range. The sampling sites were surveyed using a portable scintillometer hand-held at one meter above the ground level. Rock samples collected from jebel Glusi and Alttaka, and soil samples from the river were analyzed using gamma ray spectrometry so as to estimate- and for the fiirts time-the radiactivity concentaration which will contribute towards an establishment of a country radiation map. It is found that the activity concentration of {sup 226} Ra, {sup 228} Ra and {sup 40} K studied in soil samples ranged from 13.0-30.7 Bq/Kg, 12.5-59.9 Bq/Kg and 283.0-461.4 Bq/Kg, respectively. The calculated dose rate due to gamma radiation form the ground at one meter height ranged between 23.5 and 37.5 nGy/h with an average value of 37.5 nGy/h which correspond to annual dose equivalent of 229.9 {mu}Sv. This shows that the level of radioactivity in the surveyed area lies within the worldwide range of normal background radiation. (Author) 74 refs. , 21 tabs. , 34 figs.

Data for radioactive waste management and nuclear applications

International Nuclear Information System (INIS)

Stewart, D.C.

1985-01-01

This book is a specialized handbook on the management of radioactive waste, including information applicable to related applications. It consolidates information from many sources to develop techniques for dealing with radioactive waste management and features reports and other specialized data not available in libraries. It covers physical data, chemical data, types of radioactive wastes, and data for different operations

Studies on radioactivity monitoring proceedure for marine organisms

International Nuclear Information System (INIS)

Koyanagi, Taku; Hirano, Shigeki

1978-01-01

Suitability of several species of mollusca and seaweeds as indicator organisms for radioactivity monitoring of marine environment was examined by radioisotope tracer experiments or stable elements analyses from the standpoints of the affinities for radionuclides, the sampling procedures, and the distribution of radioactive and stable elements in the body of these organisms. Extremely high concentration factor of 54 Mn was shown by kidney of scallop suggesting the suitability for the efficient monitoring of the nuclide though the contribution of kidney to the weight of scallop was very small. Higher concentration of 54 Mn in midgut gland rather than kidney was observed in the case of other species of shellfishes but distribution of the nuclide among organs or tissues of the organisms varied during the period of intake and excretion. Ununiform distribution of radioactive and stable elements among the species of seaweeds and in the body of seaweeds observed by the tracer experiments and stable element analyses suggested the necessity of careful selection of the samples for monitoring of these nuclides. From the results of tracer experiments carried out in order to elucidate the relation between existing state of radionuclides in seawater and uptake by marine organisms, it was supposed that the complexed forms with inorganic or organic ligands in seawater were predominant species of radioactive cerium in seawater. (author)

Environmental system applied to radioactive liquid effluent release

International Nuclear Information System (INIS)

Nisti, Marcelo Bessa

2009-01-01

without monetary and environmental costs. The results showed that the dilution factors values varied according to the employed radioisotope, in increasing order from 3 H, 137 CS, 54 Mn, 60 Co to 65 Zn, following to each chemical element characteristics, significant variance among hydrogen, alkaline metal and transition metals was also showed. The dilution factor averages obtained in the first and second day of the releases were respectively 4,3 and 7,4 for 3 H, 12,0 and 16,1 for 54 Mn, 12,6 and 14,2 for 60 Co, 12,0 and 27,9 for 65 Zn, 6,2 and 13,9 for 137 Cs. This is the first study about intra-institutional dilution factor estimation using anthropic radiotracers, without any addition costs. The obtained results contribute with the subsidies to the improvement of the environmental conduct and to establish optimized procedures, under current legislation. The dilution factors were estimated in an operations and laboratory study, in only one controlled discharge of the storage tank TR1. This radioactive tracers study will have to be repeated, in order to create an institutional database. The environmental systemic study must be established by each case, depending on the characteristics of the area, the institution and the released effluents.(author)

Chemical Effects of Nuclear Transformations Vol. I. Proceedings of the Symposium on Chemical Effects Associated with Nuclear Reactions and Radioactive Transformations

International Nuclear Information System (INIS)

1965-01-01

The study of the chemical changes consequent upon the nuclear transformation of an atom that is linked with other atoms in a molecule and surrounded by other similar or dissimilar molecules has intrigued chemists for a number of years. This interest is certainly not static but if anything is increasing. The main theme of this meeting was a discussion of the suggestions and theories that have been advanced to explain the wealth of experimental observations on the behaviour of atoms at energies and in situations not normally accessible in the laboratory. Though the subject has some practical implications in the preparation of radioisotopes, this was not an important consideration at this Symposium. The first Symposium on hot-atom chemistry organized by the Agency was held in Prague in October 1960. Comparison of the past and the present state of the subject shows that a greater variety and sophistication of techniques are now being applied as the simpler approaches used in the past have been shown to be inadequate. Progress has been made in the understanding of the simpler gas system, but in liquids and solids there is still much to clarify. It is also of interest that for the majority of the work reported in these Proceedings a reactor was the radiation source, and in this field much experimental work still remains to be done. The Symposium on Chemical Effects Associated with Nuclear Reactions and Radioactive Transformations was held from 7 to 11 December 1964 in Vienna, and was attended by 136 participants from 29 countries and 4 international organizations. It was organized by the International Atomic Energy Agency in co-operation with the Joint Commission on Applied Radioactivity. The publication of these Proceedings makes the content of the papers and discussion available to a wider audience than was possible at the meeting in Vienna

Simultaneous topographic and elemental chemical and magnetic contrast in scanning tunneling microscopy

Science.gov (United States)

Rose, Volker; Preissner, Curt A; Hla, Saw-Wai; Wang, Kangkang; Rosenmann, Daniel

2014-09-30

A method and system for performing simultaneous topographic and elemental chemical and magnetic contrast analysis in a scanning, tunneling microscope. The method and system also includes nanofabricated coaxial multilayer tips with a nanoscale conducting apex and a programmable in-situ nanomanipulator to fabricate these tips and also to rotate tips controllably.

Three-dimensionality of space in the structure of the periodic table of chemical elements

International Nuclear Information System (INIS)

Veremeichik, T. F.

2006-01-01

The effect of the dimension of the 3D homogeneous and isotropic Euclidean space, and the electron spin on the self-organization of the electron systems of atoms of chemical elements is considered. It is shown that the finite dimension of space creates the possibility of periodicity in the structure of an electron cloud, while the value of the dimension determines the number of stable systems of electrons at different levels of the periodic table of chemical elements and some characteristics of the systems. The conditions for the stability of systems of electrons and the electron system of an atom as a whole are considered. On the basis of the results obtained, comparison with other hierarchical systems (nanostructures and biological structures) is performed

Treatment and conditioning of radioactive organic liquids

International Nuclear Information System (INIS)

1992-07-01

Liquid organic radioactive wastes are generated from the use of radioisotopes in nuclear research centres and in medical and industrial applications. The volume of these wastes is small by comparison with aqueous radioactive wastes, for example; nevertheless, a strategy for the effective management of these wastes is necessary in order to ensure their safe handling, processing, storage and disposal. A aqueous radioactive wastes may be discharged to the environment after the radioactivity has decayed or been removed. By contrast, organic radioactive wastes require management steps that not only take account of their radioactivity, but also of their chemical content. This is because both the radioactivity and the organic chemical nature can have detrimental effects on health and the environment. Liquid radioactive wastes from these applications typically include vacuum pump oil, lubricating oil and hydraulic fluids, scintillation cocktails from analytical laboratories, solvents from solvent extraction research and uranium refining, and miscellaneous organic solvents. The report describes the factors which should be considered in the development of appropriate strategies for managing this class of wastes from generation to final disposal. Waste sources and characterization, treatment and conditioning processes, packaging, interim storage and the required quality assurance are all discussed. The report is intended to provide guidance to developing Member States which do not have nuclear power generation. A range of processes and procedures is presented, though emphasis is given to simple, easy-to-operate processes requiring less sophisticated and relatively inexpensive equipment. 31 refs, 16 figs, 3 tabs

The Spanish general radioactive waste plan

International Nuclear Information System (INIS)

Redondo, J.M.

2007-01-01

The author summarized the current status of Spain's general radioactive waste management plan. This plan forms the basis for a national radioactive waste management policy and decommissioning strategy. It is updated periodically, the current 5. plan was approved in 1999. The most important element of the current strategy is the development of a centralized interim HLW storage facility by 2010. (A.L.B.)

Radioactive elements behaviour in multiphase intrusive series and petrological significance of radiogeochemical data

International Nuclear Information System (INIS)

Ponomareva, A.P.; Zlobin, V.A.

1982-01-01

The behaviour of radioactive elements (RE) during formation of multiphase intrusive series of various ages, types and alkalinity nature, placed in different structural formation zones of West Uzbekistan is discussed (on the basis of 230 quantitative determinations). It is established that maximum RE concentrations in the intrusive series considered are U=3-5, Th=11-17 g/t and correspond to granodiorites, adamellites, granites and granosienites. The typical behaviour for U and Th is the growth of their concentrations in the direction from gabbro- to granodiorites (granosienites) and granites, and then decrease to leucocrat granites (alkaline, biotite or bimica ones). The evolution of magmatic systems occurred not along the line of differentiation of melts, but along the line of their ''washing'' with fluid mainly at the level of magma generation and on their way to upper horizons of Earth crust. High concentrations (several times more than a clark) must occur in cases of additional RE introduction

A study on the radioactive waste management for DUPIC fuel cycle

Energy Technology Data Exchange (ETDEWEB)

Chun, Kwan Sik; Park, H. S.; Park, J. J.; Kim, J. H.; Cho, Y. H.; Shin, J. M.; Kim, Y. K.; Kim, J. S.; Kim, J. G.; Park, S. D.; Suh, M. Y.; Sohn, S. C.; Song, B. C.; Lee, C. H.; Jeon, Y. S.; Jo, K. S.; Jee, K. Y.; Jee, C. S.; Han, S. H.

1997-09-01

Part 1: The characteristics if the radioactive wastes coming from the DUPIC fuel manufacturing process were analyzed and evaluated. The gross {alpha}-activity and {alpha}-, {gamma}-spectrum of irradiated zircaloy specimens form KORI unit 1 were analyzed. In order to develop the trapping media of radioactive ruthenium oxides, trapping behavior of volatilized ruthenium oxides on various metal oxides or carbonates was analyzed. Fly ash was selected as a trapping materials for gaseous cesium. And reaction characteristics of CsNO{sub 3} and CsI with fly ash have been investigated. Also, trapping material were performed to test fly ash filter for removal of gaseous cesium under the air and hydrogen atmosphere. The applicability of fly ash to the vitrification of the spent filter was analyzed in the aspects of predictability, leachability. Good quality of Borosilicate glass was formed using Cesium spent filter. Offgas treatment system of DUPIC fuel manufacturing facility was designed and constructed in order to trap of gaseous radioactive waste from 100 batch of OREOXA furnace (the capacity : 500 g/batch). Part II: To develop chemical analysis techniques necessary for understanding chemical properties of the highly radioactive materials related to the development of DUPIC fuel cycle technology, the following basic studies were performed : dissolution of SIMFUEL (simulated fuel), determination of uranium by potentiometry and UV/Vis absorption spectrophotometry, separation of PWR spent fuel, group separation of fission products from uranium, individual separation for analysis of actinides, determination of free acid in a artificial dissolved solution of PWR spent fuel, group separation of fission products form uranium, individual separation of Sm from a mixed rare earth elements and measurement of its isotopes by TI-mass spectrometry, and characteristics of detectors in inductively coupled plasma atomic emission spectrometer (ICP-AES) suitable for analysis of trace fission

A study on the radioactive waste management for DUPIC fuel cycle

International Nuclear Information System (INIS)

Chun, Kwan Sik; Park, H. S.; Park, J. J.; Kim, J. H.; Cho, Y. H.; Shin, J. M.; Kim, Y. K.; Kim, J. S.; Kim, J. G.; Park, S. D.; Suh, M. Y.; Sohn, S. C.; Song, B. C.; Lee, C. H.; Jeon, Y. S.; Jo, K. S.; Jee, K. Y.; Jee, C. S.; Han, S. H.

1997-09-01

Part 1: The characteristics if the radioactive wastes coming from the DUPIC fuel manufacturing process were analyzed and evaluated. The gross α-activity and α-, γ-spectrum of irradiated zircaloy specimens form KORI unit 1 were analyzed. In order to develop the trapping media of radioactive ruthenium oxides, trapping behavior of volatilized ruthenium oxides on various metal oxides or carbonates was analyzed. Fly ash was selected as a trapping materials for gaseous cesium. And reaction characteristics of CsNO 3 and CsI with fly ash have been investigated. Also, trapping material were performed to test fly ash filter for removal of gaseous cesium under the air and hydrogen atmosphere. The applicability of fly ash to the vitrification of the spent filter was analyzed in the aspects of predictability, leachability. Good quality of Borosilicate glass was formed using Cesium spent filter. Offgas treatment system of DUPIC fuel manufacturing facility was designed and constructed in order to trap of gaseous radioactive waste from 100 batch of OREOXA furnace (the capacity : 500 g/batch). Part II: To develop chemical analysis techniques necessary for understanding chemical properties of the highly radioactive materials related to the development of DUPIC fuel cycle technology, the following basic studies were performed : dissolution of SIMFUEL (simulated fuel), determination of uranium by potentiometry and UV/Vis absorption spectrophotometry, separation of PWR spent fuel, group separation of fission products from uranium, individual separation for analysis of actinides, determination of free acid in a artificial dissolved solution of PWR spent fuel, group separation of fission products form uranium, individual separation of Sm from a mixed rare earth elements and measurement of its isotopes by TI-mass spectrometry, and characteristics of detectors in inductively coupled plasma atomic emission spectrometer (ICP-AES) suitable for analysis of trace fission products. (author

Separation for the determination of 59/63Ni in radioactive wastes

International Nuclear Information System (INIS)

Lee, Chang Heon; Choi, Kwang Soon; Jee, Kwang Young; Kim, Won Ho; Jung, Kie Chul

2005-01-01

A study on the separation of 99 Tc, 94 Nb, 55 Fe, 90 Sr and 59/63 Ni in various radioactive wastes discharged from nuclear power plants has been performed for a use in their quantification which is indispensable for the evaluation of the radionuclide inventory. Ni was recovered along with Ca, Mg, Al, Cr, Ti, Mn, Ce, Na, K. and Cu through the sequential separation procedure of Re (as a surrogate of 99 Tc), Nb, Fe and Sr by anion exchange and Sr-SPec extraction chromatography. In this research, chemical separation of Ni from the co-existing elements was investigated by cation exchange and Ni-Spec extraction chromatography. Precipitation behaviour of Ni and the co-existing elements with dimethylglyoxime(DMG) was investigated in ammonium citrate/ethanol-H 2 O and tartaric acid/acetone-H 2 O in order to purify separated Ni fractions and to prepare 59/63 Ni source for the radioactivity measurement using a gas proportional counter. Recovery of Ni separated through ion exchange chromatographic separation procedure was 93.1% with relative standard deviation of 0.9%. In addition, recovery of Ni with DMG in the tartaric acid/acetone-H 2 O was 85.6% with relative standard deviation of 1.9%

Sodalite-type radioactive waste solidification product and method of synthesizing the same

International Nuclear Information System (INIS)

Koyama, Masashi; Yoshida, Takumasa.

1995-01-01

Radioactive waste solidification products formed by solidifying radioactive wastes comprising halides such as chlorides of alkali metal elements, alkaline earth metal elements, rare earth elements, noble metal elements generated upon dry-type reprocessing of nuclear fuels and separation of dry-type high level liquid wastes, are solidified to stable products by incorporating radioactive wastes in the form of halides into a cavity of sodalite condensation cage of aluminosilicates having three dimensional skeleton structure. Alternatively, NaOH, Al 2 O 3 , SiO 2 are mixed and heated to 600 to 900degC to form an intermediate reaction products, and then the reaction products are mixed with the halides and heated to form sodalite-type radioactive water solidification products. Thus, the halides in fission products can be held by the three dimensional skeleton structure similar with that of sodalite which is a sort of natural minerals containing chlorides, thereby enabling to solidify them stably. (N.H.)

Characterization of chemical elements of fruits of Leucaena leucocephala in riverside areas of the Piracicaba River Basin, São Paulo, Brazil; Caracterização de elementos químicos de frutos de Leucaena leucocephala em áreas ribeirinhas da Bacia do Rio Piracicaba, São Paulo, Brasil

Energy Technology Data Exchange (ETDEWEB)

França, Elvis J.; Magalhães, Marcelo R.L. de; Ferreira, Fabiano S., E-mail: ejfranca@cnen.gov.br, E-mail: marcelo_rlm@hotmail.com, E-mail: biologofabiano10@gmail.com [Centro de Ciência Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Fernandes, Elisabete A. de N.; Fonseca, Felipe Y.; Rodrigues, Vanessa S.; Cavalca, Isabel P.O.; Camilli, Leandro, E-mail: lis@cena.usp.br, E-mail: vsrodrigues89@gmail.com, E-mail: i-cavalcante@uol.com.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Silva, Bruno F., E-mail: brunodasilva1996@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

2017-07-01

The species Leucaena leucocephala is present in several environments. Its fruit is widely used in cattle feed. However, it is classified as an invasive species, causing problems in the restoration of impacted areas. The Piracicaba River Basin is heavily affected by urbanization and industrialization, which shows the proliferation of this species. Considering the importance of this tree species for Brazil, the present study quantifies chemical elements in fruits of this species by applying Instrumental Neutronic Activation Analysis, method k{sup 0}. Samples were collected in riverside areas of the Piracicaba Municipality, São Paulo, Brazil, at different periods (dry and rainy season). After collection, the samples were shattered and transferred to polyethylene capsules and irradiated with neutrons. Certified reference materials were used to evaluate the quality of the analytical procedure, all material was irradiated under a thermal neutron flux of 10{sup 13} cm-2s-1 for 8 hours. Ni-Cr alloy was used for the monitoring of thermal neutron flux. High Resolution Range Spectrometry with HPG detectors was employed for the measurement of the induced radioactivity, allowing the quantification of the chemical elements. Compared with available results of chemical analysis of pods, the chemical elements Ca, K, Ba, Cr and Se presented high concentrations. We also quantified chemical elements of environmental relevance such as As, Hg, Br, Ce, Cs, Eu, Hf, La, Rb, Sb, Sc, Sm, Ta, Tb, Th and Yb, indicating the need for element dynamics studies in the environments occupied by this invasive species.